The visualization and evaluation of fruit vascular bundles in grape are indispensable for understanding the development and growth of the fruit. The vascular bundles in grape are as thin as human hair, and strongly ad...The visualization and evaluation of fruit vascular bundles in grape are indispensable for understanding the development and growth of the fruit. The vascular bundles in grape are as thin as human hair, and strongly adhere to flesh cells, making it difficult to isolate individual intact vessel elements. Currently there is little information about methods to characterize grape vascular tissue. In this study, we describe an easy and effective technique to visualize the xylem cell structure of the ‘Red Globe' grape(Vitis L.). The intact vascular bundles of the grape were isolated through enzymatic degradation of flesh cells by hydrolases which were effective in removing flesh cells from vascular bundles. This enabled the illustration of the fine surface structure of vessel elements and their arrangement in the vascular bundles of the grape. This modified method to separate the vascular bundles into individual vessel elements was more effective than former methods of manually shaking to isolate individual vessels. Clear images of xylem vessel arrangement and structural characteristics of individual vessel element were acquired by light microscopy(BX51, Olympus, Tokyo, Japan), transmission electron microscopy(Tecnai 12, Philips, Netherlands) and scanning electron microscopy(GeminiSEM 300, Carl Zeiss, Germany). In addition, the 3D structure of vessel elements was observed using confocal laser scanning microscopy(Zeiss: model: LSM-880, Oberkochen, Germany). The imaging techniques for visualizing and analyzing the structure of xylem vessels in grape described in this study are an improvement of past methods. An effective method to isolate grape vascular bundles from flesh cells was also developed, which enables the imaging of the fine surface structure of vessel elements and their arrangement in grape vascular bundles. By adjusting the process of maceration of vascular bundles, an easy and effective method was developed to gently disrupt the plant tissue and isolate individual vessel elements. These improved techniques are suitable to observe the intact morphology of vascular bundles in the grape, improve experimental efficiency and accelerate new discoveries on the anatomical structure of the grape.展开更多
This study investigates the paleodepositional conditions of the No.6 Seam of the Madzaringwe Formation in Makhado and Voorburg south area of the Soutpansberg Coalfield(Limpopo Province,South Africa)utilizing organic p...This study investigates the paleodepositional conditions of the No.6 Seam of the Madzaringwe Formation in Makhado and Voorburg south area of the Soutpansberg Coalfield(Limpopo Province,South Africa)utilizing organic petrography and inorganic geochemical proxies.The coals are predominantly high-volatile bituminous B-A rank with high ash yields(avg.36.1 wt%),characterized by high-vitrinite(~41.5 vol%),moderate-to-high inertinite(9.8 vol%–33.7 vol%)and low liptinite(~2.3 vol%).The distribution of inertinite varies among different coal horizons(from bottom-lower to middle-upper),suggesting differential oxidation conditions and/or paleofire occurrence.Vitrinite-to-inertinite(V/I)ratio,tissue preservation–gelification index(TPI–GI),and groundwater–vegetation index(GWI–VI)plots,indicate that the peat-forming forest-swamp vegetation accumulated under mesotrophic-to-rheotrophic hydrological conditions.The presence of structured macerals(i.e.,telinite,collotelinite,fusinite,and semifusinite)suggests well-preserved plant tissues,whereas framboidal pyrite and sulphur content(0.24 wt%–2.16 wt%)point to brackish-water influence at the peat stage.The coals contain quartz,kaolinite,siderite,muscovite,dolomite,calcite,and pyrite minerals,most of which were likely sourced from felsic igneous rocks.The Al/(Al+Fe+Mn)and(Fe+Mn)/Ti ratios for the studied samples range between 0.24–0.97 and 0.57–70.10,respectively.The ratios,Al–Fe–Mn plot,and presence of massive botryoidal-type pyrite imply some influence of meteoric waters or fluids from hydrothermal activity post-deposition.Moreover,the chemical index of alteration(CIA:98.25–99.67),chemical index of weathering(CIW:92.04–97.66),and A–CN–K ternary diagram suggest inorganic matter suffered strong chemical weathering,indicating warm paleoclimatic conditions during the coal formation.展开更多
The hydrocarbon generation potential of the Campano-Maastrichtian to Paleogene shales from the Benin Flank(located in SW Nigeria)of the Anambra Basin,has been previously investigated mostly by studying outcrops and by...The hydrocarbon generation potential of the Campano-Maastrichtian to Paleogene shales from the Benin Flank(located in SW Nigeria)of the Anambra Basin,has been previously investigated mostly by studying outcrops and by relatively few subsurface data-based studies.Thus,it is expedient undertaking an assessment of the hydrocarbon generation potential of this frontier area from subsurface samples.Campano-Maastrichtian to Paleogene shale samples obtained from Egoli-1 borehole in the Benin Flank of the Anambra Basin are studied by means of HAWK programmed pyrolysis,organic petrography,and mineralogy(XRD),with the aim to explore the petroleum-generating potential and the thermal maturity.The obtained results display a significant variation of the TOC content ranging from very low(<0.5%)to significant(>5%),indicating poor to excellent oil potential based on S_(2)values under the condition,of course,the studied formations reached the oil window.The shales of the Nsukka and Imo Formations display lower petroleum-generating potential than these of the Mamu Formation.All the studied samples are dominated by gas-prone(type III)and inert(type IV)kerogens,with few displaying mixed II/III(oil-and gas-prone).The organic-petrography observations support partly the results of the HAWK programmed pyrolysis,as they reveal an organic-richer Mamu Formation in comparison to the Nsukka and Imo Formations;huminite/vitrinite particles(both indigenous and recycled)along with variable contents of liptinite(mostly alginite and bituminite)and inertinite macerals(mostly inertodetrinite)are hosted in the shales.The latter display a typical composition for fine-grained clastic sediments;mostly kaolinite,illite/montmorillonite,quartz,and subordinately,anatase.In terms of thermal maturity,huminite/vitrinite reflectance data points to immature stage;however,the occurrence of solid bitumens,displaying equivalent vitrinite reflectance values within the oil window,points to an active petroleum system in sequences deeper than the examined ones.展开更多
Knowing that flavored products would increase the use of olive oil by non-traditional consumers and enhance the added value of this valuable agricultural product,the virgin olive oil(VOO)was flavored with the seeds of...Knowing that flavored products would increase the use of olive oil by non-traditional consumers and enhance the added value of this valuable agricultural product,the virgin olive oil(VOO)was flavored with the seeds of Pimpinella anisum(Green anise)using three different methods:classic maceration,ultrasonic assisted maceration and direct addition of the essential oil(EO).These methodswere compared under two main criteria:time and level of aromatization.The physico-chemical parameters and the thermal stability of flavored oils prepared by the three methods were determined by AOAC titration method and GC–MS analysis so as to compare the aromatization effect of the three methods.The trans-anethole is the major component of the EO of anise seeds as well as the indicator of the level of aromatization.GC/MS analysis results of the flavored oils showed that the diffusion of trans-anethole in the flavored oil by direct addition of EO was very important(36.3%of the total volatile fraction of the flavored oil)in comparison to the oil flavored by ultrasonic assisted maceration or classic maceration(respectively 26.59%and 23.85%).These different aromatization methods ensure an improvement in the quality of VOO with an enrichment in polyphenols estimated at 35%in the case of ultrasonic flavored oil,an increase in the content of carotenoids and chlorophylls(67%and 21%respectively)in the event of aromatization by classic maceration,and a decrease in specific absorbency at 232 nmestimated at 29%during aromatization by addition of EO as well as a decrease in the peroxide value estimated at 26%in oil flavored by classic maceration unlike in oil flavored by ultrasoundwhich has seen an increase of around 20%.The aromatization was able to maintain the stability of the oils and its qualification as VOO with a gain in induction time in the case of treatment at 60℃ estimated at 29 and 27.5 d respectively in oils flavored by addition of EO and by conventional maceration,an improvement resistance to degradation concerning K_(232) and K_(270) of all flavored oils which varied from 15 to 40 d in the case of treatment at 60℃ and 3 h resistance to degradation of oils treated at 130℃ for K_(232).Polyphenols,chlorophyll pigments and carotenoids play an important role in oxidative stability due to their antioxidant nature and their degradation during heating is very complex.All of these physico-chemical changes have increased the thermal stability of flavored oils with better resistance to oxidation of flavored oil by classic maceration in compared to oil flavored by adding EO and the oil flavored by using ultrasound.展开更多
AIM: To facilitate close contacts between transplanted cardiomyocytes and host skeletal muscle using cell fusion mediated by hemagglutinating virus of Japan envelope(HVJ-E) and tissue maceration. METHODS: Cardiomyocyt...AIM: To facilitate close contacts between transplanted cardiomyocytes and host skeletal muscle using cell fusion mediated by hemagglutinating virus of Japan envelope(HVJ-E) and tissue maceration. METHODS: Cardiomyocytes(1.5 × 106) from fetal rats were first cultured. After proliferation, some cells were used for fusion with adult muscle fibers using HVJ-E. Other cells were used to create cardiomyocyte sheets(area: about 3.5 cm2 including 2.1 × 106 cells), which were then treated with Nile blue, separated, and transplanted between the latissimus dorsi and intercostal muscles of adult rats with four combinations of HVJ-E and/or Na OH maceration: G1: HVJ-E(+), Na OH(+), Cardiomyocytes(+); G2: HVJ-E(-), NaO H(+), Cardiomyocytes(+); G3: HVJ-E(+),Na OH(-), Cardiomyocytes(+); G4: HVJ-E(-), Na OH(-), Cardiomyocytes(-). At 1 and 2 wk after transplantation, the four groups were compared by detection of beating domains, motion images using moving target analysis software, action potentials, gene expression of MLC-2v and Mesp1 by reverse transcription-polymerase chain reaction, hematoxylin-eosin staining, and immunostaining for cardiac troponin and skeletal myosin.RESULTS: In vitro cardiomyocytes were fused with skeletal muscle fibers using HVJ-E. Cardiomyocyte sheets remained in the primary transplanted sites for 2 wk. Although beating domains were detected in G1, G2, and G3 rats, G1 rats prevailed in the number, size, motion image amplitudes, and action potential compared with G2 and G3 rats. Close contacts were only found in G1 rats. At 1 wk after transplantation, the cardiomyocyte sheets showed adhesion at various points to the myoblast layer in the latissimus dorsi muscle. At 2 wk after transplantation, close contacts were seen over a broad area. Part of the skeletal muscle sarcoplasma seemed to project into the myocardiocyte plasma and some nuclei appeared to share both sarcoplasmas.CONCLUSION: The present results show that close contacts were acquired and facilitated the beating function, thereby providing a new cellular transplantation method using HVJ-E and NaO H maceration.展开更多
The effect of lanthanum on the growth and extracellular enzyme activity of Erwinia chrysanthemi(Ech) was studied. Lanthanum inhibited the growth of Ech in solid culture at the concentration of 50, 100, 150, 200, 250, ...The effect of lanthanum on the growth and extracellular enzyme activity of Erwinia chrysanthemi(Ech) was studied. Lanthanum inhibited the growth of Ech in solid culture at the concentration of 50, 100, 150, 200, 250, 300 and 350 mgL-1, and the inhibition increased with the increase of the RE concentration. The formation of colony delayed and the diameter of colony decreased. Lanthanum stimulated the growth of Ech within 24h when the lanthanum concentration was less than 200 mgL-1 in liquid medium, but significantly inhibited the growth of Ech with the increase of lanthanum concentration and culture time. When the concentration was higher than 350 mgL-1, the growth of Ech was inhibited completely both in solid and liquid culture. The extracellular enzyme acitivity of Ech was affected by lanthanum at 200 mgL-1. The activity of cellulose was promoted more than that of protease but the activity of pectinase was decreased. The maceration to potato tuber tissue decreased when the cell free filtrate was tr展开更多
AIM To examine the efficacy of three extraction techniques: Soxhlet-extraction(SE), cold-maceration(CM) and microwave-assisted-extraction(MAE) using 80% methanol as solvent. METHODS The study was performed on each of ...AIM To examine the efficacy of three extraction techniques: Soxhlet-extraction(SE), cold-maceration(CM) and microwave-assisted-extraction(MAE) using 80% methanol as solvent. METHODS The study was performed on each of 50 g of Vernonia amygdalina(VA) and Occimum gratissimum(OG) leaves respectively. The percentage yield, duration of extraction, volume of solvent used, qualitative and quantitative phytoconstituents present was compared. The biological activities(hypoglycemic effect) were investigated using albino wistar rat model of diabetes mellitus(n = 36) with a combined dose(1:1) of the two plants leaf extracts(250 mg/kg b.w.) from the three methods. Theextracts were administered orally, once daily for 21 d.RESULTS In this report, the percentage VA extract yield from MAE was highest(20.9% ± 1.05%) within 39 min using 250 m L of solvent, when compared to the CM(14.35% ± 0.28%) within 4320 min using 900 m L of solvent and SE(15.75% ± 0.71%) within 265 min using 500 m L of solvent. The percentage differences in OG extract yield between: MAE vs SE was 41.05%; MAE vs CM was 46.81% and SE vs CM was 9.77%. The qualitative chemical analysis of the two plants showed no difference in the various phytoconstituents tested, but differs quantitatively in the amount of the individual phytoconstituents, as MAE had significantly high yield(P > 0.05) on phenolics, saponins and tannins. SE technique gave significantly high yield(P > 0.05) on alkaloid, while CM gave significant high yield on flavonoids. The extracts from CM exhibited a significantly(P > 0.05) better hypoglycemic activity within the first 14-d of treatment(43.3% ± 3.62%) when compared to MAE(36.5% ± 0.08%) and SE methods(33.3% ± 1.60%). However, the percentage hypoglycemic activity, 21 d post-treatment with 250 mg/kg b.w. extract from MAE was 72.6% ± 1.03% and it was more comparable to 10 mg/kg b.w. glibenclamide treated group(75.0% ± 0.73%), unlike the SE(69.5% ± 0.71%) and CM(69.1% ± 1.03%). CONCLUSION CM technique produces extract with better hypoglycemic activity, whereas; MAE is a better option for high yield of phytoconstituents using less solvent within a short time.展开更多
Background: Artemisia afra is an indigenous plant used in Africa. It is used in traditional medicine to treat a variety of diseases caused by bacterial infections. As a result, developing innovative therapeutic method...Background: Artemisia afra is an indigenous plant used in Africa. It is used in traditional medicine to treat a variety of diseases caused by bacterial infections. As a result, developing innovative therapeutic methods using natural ingredients to combat pathogenic germs is critical. Methodology: Artemisia afra leaves were extracted using maceration extraction utilizing three solvents (petroleum ether, ethanol, and dichloromethane). Fresh leaves were extracted using hydrodistillation. The agar well diffusion method was used to test the crude extract and essential oil leaves of Artemisia afra against different human pathogenic bacteria strains (E. coli, S. aureus, E. faecalis, and K. pneumonia) at different concentrations in the presence of a positive (ciprofloxacin 5.0 μg) and negative (DMSO) control. Results: Artemisia afra revealed the presence of alkaloids, flavonoids, tannins, saponins, anthraquinones, terpenoids, coumarins, phenolic quinones, cardiac glycosides, and steroids. It showed that the highest antibacterial activity given by the ethanol extract had highly inhibition zones against gram-positive and gram-negative bacteria. The essential oil extract was effective against all tested bacteria. Conclusion: Plant crude extracts and essential oils may have antibacterial properties due to the synergistic activity of two or more active secondary metabolites.展开更多
<strong>Background:</strong><span style="font-family:;" "=""> <i>Celosia laxa (</i>Amaranthaceae) is mainly a west African plant species used in Traditional Medic...<strong>Background:</strong><span style="font-family:;" "=""> <i>Celosia laxa (</i>Amaranthaceae) is mainly a west African plant species used in Traditional Medicine as an anthelmintic, anticancer, antibacterial and analgesic agent. The seeming prevalence of worm infection in Gwandu </span><span style="font-family:;" "="">community of Gwandu Local Government Area of Kebbi State-Nigeria</span><span style="font-family:;" "=""> prompted this study. <b>Methods:</b><i> </i>Whole plant of <i>C. laxa</i> extracts obtained through maceration in aqueous (AE), methanol (ME) and hexane (HE) solvents were investi</span><span style="font-family:;" "="">gated for their anthelmintic activity against Indian earthworms (<i>Pheretima posthuman) </i>at four different (gradient) concentrations of<i> </i>10, 20, 40 and 8<span>0 (mg/ml) for each extract. The study involved the determination of time of paralysis (P) and time of death (D) of the worms. <b>Results:</b> Both the aqueous and ethanolic extracts exhibited significant anthelmintic activity at the highest con</span>centration of 80 mg/ml as compared to the standard drug, praziquantel (10</span><span style="font-family:;" "=""> </span><span style="font-family:;" "="">mg/ml). Consequently, the aqueous extract showed a higher activity at 80</span><span style="font-family:;" "=""> </span><span style="font-family:;" "="">mg/ml compared to standard praziquantel at 10</span><span style="font-family:;" "=""> </span><span style="font-family:;" "="">mg/ml (with no significant value of p</span><span style="font-family:;" "=""> </span><span style="font-family:;" "=""><</span><span style="font-family:;" "=""> </span><span style="font-family:;" "="">0.05). The time of paralysis and death observed for AE was 13.0 ± 1.8 and 16.8 ± 1.5 while the ME was less bioactive with 15.7 ± 0.5 and 23.0 ± 0.0 respectively. However, on the other hand, the hexane extract recorded no-activity on all the test</span><span style="font-family:;" "=""> </span><span style="font-family:;" "="">sample concentrations, compared</span><span style="font-family:;" "=""> to </span><span style="font-family:;" "="">the standard drug (with a significant difference of p-value, p</span><span style="font-family:;" "=""> </span><span style="font-family:;" "="">></span><span style="font-family:;" "=""> </span><span style="font-family:;" "="">0.05). <b>Conclusion:</b> It was concluded that the leaves of <i>C. laxa</i> </span><span style="font-family:;" "="">are</span><span style="font-family:;" "=""> likely to yield a potent anthelminthic drug owing to soluble phytoconstituent which are largely hydrophilicity extracted by the polar solvents. Also, considering that the plants’ mode of preparation for use by the locals was aqueous decoction before administration, the folkloric therapeutic claims can be said to have been justified.</span>展开更多
In this research,molecular structure models were developed respectively for Shenhua coal vitrinite concentrates(SDV)and inertinite concentrates(SDI),on the basis of information on constitutional unit of Shenhau coal a...In this research,molecular structure models were developed respectively for Shenhua coal vitrinite concentrates(SDV)and inertinite concentrates(SDI),on the basis of information on constitutional unit of Shenhau coal and elemental analysis results obtained from^(13)C-NMR analysis characterization,FTIR analysis characterization,X-ray diffraction XRD and XPS analysis characterization.It can be observed from characterization data and molecular structure models that the structure of SDV and SDI is dominated by aromatic hydrocarbon,with aromaticity of SDI higher than that of SDV;SDV mainly consists of small molecule basic structure unit,while SDI is largely made from macromolecular structure unit.Based on bond-level parameters of the molecular model,the research found through the autoclave experiment that vitrinite liquefaction process goes under thermodynamics control and inertinite liquefaction process under dynamics control.The research developed an efficient directional direct coal liquefaction technology based on the maceral characteristics of Shenhua coal,which can effectively improve oil yield and lower gas yield.展开更多
This paper discussed the petrographic characteristics of No.6 coal from the Xiaoyugou mine,Jungar Coalfield,Ordos Basin,China.10 samples(7 coal,1 parting mudstone and 2 floor mudstone)were analysed by microscopical an...This paper discussed the petrographic characteristics of No.6 coal from the Xiaoyugou mine,Jungar Coalfield,Ordos Basin,China.10 samples(7 coal,1 parting mudstone and 2 floor mudstone)were analysed by microscopical and geochemical methods.Four maceral compositions and several associated elements parameters were selected as indicators and corresponding diagrams were drawn to explicate the sedimentary environment.The results indicate that the maceral is dominated by vitrinite and minerals are mainly kaolinite in the No.6 coal.The sedimentary facies vary from barrier island system to tidal-flat which is a deposition process of water body shallowing and the coal-forming plants are herbs and woody plants formed in swamps.展开更多
Inertinite maceral compositions of the Late Permian coals from three sections in the terrestrial and paralic settings of eastern Yunnan are analyzed in order to reveal the paleo-fire events and the atmospheric oxygen ...Inertinite maceral compositions of the Late Permian coals from three sections in the terrestrial and paralic settings of eastern Yunnan are analyzed in order to reveal the paleo-fire events and the atmospheric oxygen levels in the latest Permian. Although the macerals in the studied sections are generally dominated by vitrinite, the inertinite group makes up a considerable proportion. Its content increases upward from the beginning of the Late Permian to the coal seam near the Permian- Triassic boundary. Based on the microscopic features and the prevailing theory that inertinite is largely a by-product of paleo-fires, we suggest that the increasing upward trend of the inertinite abundance in the latest Permian could imply that the Late Permian peatland had suffered from frequent wildfires. Since ignition and burning depend on sufficient oxygen, a model-based calculation suggests that the 02 levels near the Wuchiapingian/Changhsingian boundary and the Permian-Triassic boundary are 27% and 28% respectively. This output adds supports to other discoveries made in the temporal marine and terrestrial sediments, and challenges the theories advocating hypoxia as a mechanism for the PermianTriassic boundary crisis.展开更多
This study presents a review of the various methods to predict the spontaneous combustion liability of coal and coal-shale. The relative propensity of coal to undergo self-heating can be established by different metho...This study presents a review of the various methods to predict the spontaneous combustion liability of coal and coal-shale. The relative propensity of coal to undergo self-heating can be established by different methods. These methods are well established in their usage, but the fact that no particular test method has become a standard to predict the spontaneous combustion liability indicates that doubt still exists as to the validity of all of them. The underlying principle of all the tests is that the more readily the coal undergoes exothermic oxidation, the more liable it is to self-heat. Comprehensive studies that centres on the international position on research being conducted by academics, different research institutes and industries on spontaneous combustion of coal and coal mine fires were evaluated. Relationships between the geochemical analysis (proximate and ultimate analysis, forms of sulphur, petrographic properties, X-ray diffraction and X-ray fluorescence) and spontaneous combustion testing methods (numerical and experimental approaches) used to predict the spontaneous combustion liability of coal were reviewed. The combination of these tests provides a better understanding of the mechanism that controls the spontaneous combustion phenomena. However, irrespective of the extensive studies that have been conducted over time, spontaneous combustion is still a major problem in the coal value chain.展开更多
The filtration and dewatering of fine clean coal not only ensure industrial water recycle in coal washing plant,but also reduce the moisture of coal product in order to meet the requirements of combustion or coking in...The filtration and dewatering of fine clean coal not only ensure industrial water recycle in coal washing plant,but also reduce the moisture of coal product in order to meet the requirements of combustion or coking industry.Fine clean coal is mainly composed by organic matter,and the property difference of different organic matter determines the filtration and dewatering behavior.In this investigation,vitrinite and inertinite were separated from a clean bituminous coal,and the comparative filtration and dewatering behavior of vitrinite and inertinite were conducted.The results showed that inertinite has lower dewatering rate and higher filter cake moisture than vitrinite.The analysis of filter cake structure showed that inertinite particle is easier to be broken into small particles due to the difference of mechanical properties,thus forming more compact filter cake than vitrinite.The analysis of particle surface properties showed that vitrinite is more hydrophobic than inertinite,which makes water easier drained from filter cake.The simulation study showed that the structure of inertinite is more porous than that of vitrinite,and the interaction between inertinite and water is stronger than that between vitrinite and water.This study provides a theoretical basis for improving coal dewatering by selectively improving coal maceral hydrophobicity.展开更多
The objective of this paper is to evaluate the coal petrology characteristics of slack middlings(13–0.5 mm)of dense media separation and flotation middlings from Qianjiaying fat coal preparation plant.Phase compositi...The objective of this paper is to evaluate the coal petrology characteristics of slack middlings(13–0.5 mm)of dense media separation and flotation middlings from Qianjiaying fat coal preparation plant.Phase composition,macerals distribution,microlithotype and mineral occurrence of the two middlings were studied by XRD analysis and polarized light microscopy observation.Macerals distribution and wettability of the float-and-sink products separated from the middlings after grinding was investigated to determine the liberation degree.Studies show that there are more vitrinite and mineral,but less inertinite in slack middlings than in flotation middlings.Macerals associated with mineral in slack middlings is 69.85%,by volume,which is 17.86%higher than that in flotation middlings.Minerals in slack middlings are dominated by pyrite and clay,which are disseminated with the diameter less than2 lm.The main mineral in flotation middlings is clay with size range of 2–20 lm.Single macerals in the slack middlings are diffcult to liberate due to the fne-grained minerals.After grinding,macerals associated with minerals in the slack middlings decrease to 46.73%,by volume,which is higher than in flotation middlings by 25.89%,by volume.For slack middlings with poor liberation degree,density fractions below1.8 g/cm3is hydrophobic with contact angle above 71.5°.For the well liberated flotation middlings,there is signifcant wettability difference among the float-and-sink products.This research is the theoretical basis to realize re-separation of middlings.展开更多
The distribution and verticals variation of geochemical components in the Kasnau-Matasukh lignites of Nagaur Basin, Rajasthan, were investigated using microscopy, proximate and ultimate analyses, Rock-Eval Pyrolysis, ...The distribution and verticals variation of geochemical components in the Kasnau-Matasukh lignites of Nagaur Basin, Rajasthan, were investigated using microscopy, proximate and ultimate analyses, Rock-Eval Pyrolysis, X-ray diffraction and Fourier Transform Infrared analyses, and major/minor/trace element determination. The relationship of elements with ash content and with macerals have also been discussed. These lignites are stratified, black, dominantly composed of huminite group macerals with subordinated amounts of liptinite and inertinite groups. They are classified as type-III kerogen and are mainly gas prone in nature. The concentration (in vol%) of mineral matter is seen to increase towards upper part of seam and so is the concentration (in wt%) of the volatile matter, elemental carbon and sulphur. The common minerals present in these lignitesare mixed clay layer, chlorite, and quartz as identified by X-ray diffraction study. Compared with world average in brown coal, the bulk concentration of Cu is anomalously high in most of the samples while Cd is 2-3 times high and Zn is high in one band. Based on interrelationship, different pyrite forms are noticed to have different preferential enrichment of various elements. The concentration of disseminated pyrite is more than the other pyrite forms and is followed by discrete pyrite grains and massive pyrite.展开更多
Lignite samples collected from Vastan, Rajpardi and Tadkeshwar lignite mines of Cambay basin (Gujarat) were subjected to organic petrographic investigations and geochemical analyses and the data, thus generated, is ...Lignite samples collected from Vastan, Rajpardi and Tadkeshwar lignite mines of Cambay basin (Gujarat) were subjected to organic petrographic investigations and geochemical analyses and the data, thus generated, is used to reconstruct the paleodepositional history of these lignite sequences. The lignites of Cambay basin dominantly comprise huminite maceral group (71.6%-86.3%) followed by liptinite (10.1%-19.3%) and inertinite (3.6%-11.0%) maceral groups. The mineral matter varies from 9.0% to 20.0%. The petrography based facies model indicates that these lignites have high values of gelification index (GI) and low tissue preservation index revealing a continuous wet condition in the basin and a relatively slower rate of subsidence during the decay of organic matter. On several occasions, during the formation of seams in Tadkeshwar, Rajpardi and Vastan mines, the value of GI exceeded 10 which indicates a forest permanently flooded and the cause of pronounced degree of degradation. However, few sections in Tadkeshwar seam had relatively drier spells of environmental conditions due to fluctuation in the water table as revealed by moderately high content of inertinite macerals. This is specially indicated by the occurrence of funginite which normally thrives in the upper oxy- genated peatigenic layer and indicates prevalence of oxic conditions during plant deposition. Such conditions prevailed during a transgressive phase but there were intermittent fluvial activities also giving rise to supratidal flood plain as reflected in the form of associated carbonaceous shales in the basin.展开更多
The pyrolysis characteristics of Shendong Shangwan coal and its macerals concentrate were investigated using thermogravimetry (TG) coupled with mass spectrometry (MS). The evolved gases were analyzed online by MS ...The pyrolysis characteristics of Shendong Shangwan coal and its macerals concentrate were investigated using thermogravimetry (TG) coupled with mass spectrometry (MS). The evolved gases were analyzed online by MS spectroscopy. The results of TG/DTG (derivative thermogravimetry) show ths vitrinite concentrate has greater weight loss rate and higher volatile yield than the other two samples. More light hydrocarbons C1-C5 are released from the vitfinite concentrate than from the Shendong Shangwan coal and inertinite concentrated in the process of pyrolysis. Three samples have similar shape curves of evolved gases of C2~C5 with different intensities. When the pyrolysis temperature was lower than 418℃, the amount of C6H6 evolved in the process of pyrolysis of inertinite concentrated was higher than that of raw coal and vitrinite concentrate. As the temperature rising, the production rate of C6H6 increased. Below 672℃, C6H6 evolution rate of vitrinite concentrate was far greater than the other two samples; the main evolution temperature range of C7H8 was 400℃ to 700℃ for the three samples. The amount of HE and H20 released first increased and then decreased with the temperature increase while more H2 released for pyrolysis of inertinite concentrated and more H20 released for the pyrolysis of vitrinite concentrate.展开更多
Multiple sets of thick coal beds characterized by simple structure and shallow burial depth were developed in the Early and Middle Jurassic strata of the Ordos Basin, northwestern China. The huge reserves of this high...Multiple sets of thick coal beds characterized by simple structure and shallow burial depth were developed in the Early and Middle Jurassic strata of the Ordos Basin, northwestern China. The huge reserves of this high quality coal have a high commercial value. We studied the coal's petrologic characteristics and its maceral distribution to determine the maceral's contribution to generation of oil and gas. The results show that the Jurassic coals in the Ordos Basin have special petrological features because of the Basin's unique depo- sitional environment which was mainly a series of high-stand swamps in the upper fluvial system. These petro- graphic features are a result of the development of typical inland lakes where some sand bodies were formed by migrating rivers. After burial, the peat continued to undergo oxidizing conditions, this process generated extensive higher inertinite contents in the coals and the vitrinite components were altered to semi-vitrinite. The macroscopic petrographic types of these Jurassic coals are mainly semi-dull coal, dull coal, semilustrous and lustrous coal. The proportions of semi-dull coal and dull coal are higher in the basin margins, especially in the area near the northern margin. The numbers of semilustrous and lustrous coals increase southwards and towards the central basin. This situation indicates that different coal-forming swamp environments have major controlling effects on the coal components. Another observation is that in the Ordos' coal sequences, especially in the lower part, some sandstone beds are thick, up to 20 m with a coarse grain size. The higher fusinite content in the macerals accompanies a higher semi-vitrinite content with more complete and regular plant cell structure. The fusinite structure is clear and well preserved. After burial, the lithology of the roof and floor rocks can continue to affect the evolution of coal petrology. The sand bodies in the roof and floor exhibit good physical conditions so that pore water can maintain a long-term state of oxidation, circulation and connection to the coal. So coal components remain in an oxidation environment for a long time. Conversely, in the basin center, lacustrine facies developed and peat was rapidly covered by mudstone after burial and subsequent coal beds rapidly entered a reducing environment. As a result, abundant gelatification occurred and the vitrinite content increased. E^inite often accumulated in a specific position in the coal bed. Although the average exinite content is not high on the whole, it does significantly contribute to the total hydrocarbon generation. The exinite content has been underestimated, especially the amorphous bituminous fluid and its importance is emphasized here. The reason is that the fluid flows easily into fusinite which has strong rigidity, or flows into some fissures, where it is commonly neglected.展开更多
基金supported by the National Natural Science Foundation of China (Grant Nos. 31872050 and 32102348)。
文摘The visualization and evaluation of fruit vascular bundles in grape are indispensable for understanding the development and growth of the fruit. The vascular bundles in grape are as thin as human hair, and strongly adhere to flesh cells, making it difficult to isolate individual intact vessel elements. Currently there is little information about methods to characterize grape vascular tissue. In this study, we describe an easy and effective technique to visualize the xylem cell structure of the ‘Red Globe' grape(Vitis L.). The intact vascular bundles of the grape were isolated through enzymatic degradation of flesh cells by hydrolases which were effective in removing flesh cells from vascular bundles. This enabled the illustration of the fine surface structure of vessel elements and their arrangement in the vascular bundles of the grape. This modified method to separate the vascular bundles into individual vessel elements was more effective than former methods of manually shaking to isolate individual vessels. Clear images of xylem vessel arrangement and structural characteristics of individual vessel element were acquired by light microscopy(BX51, Olympus, Tokyo, Japan), transmission electron microscopy(Tecnai 12, Philips, Netherlands) and scanning electron microscopy(GeminiSEM 300, Carl Zeiss, Germany). In addition, the 3D structure of vessel elements was observed using confocal laser scanning microscopy(Zeiss: model: LSM-880, Oberkochen, Germany). The imaging techniques for visualizing and analyzing the structure of xylem vessels in grape described in this study are an improvement of past methods. An effective method to isolate grape vascular bundles from flesh cells was also developed, which enables the imaging of the fine surface structure of vessel elements and their arrangement in grape vascular bundles. By adjusting the process of maceration of vascular bundles, an easy and effective method was developed to gently disrupt the plant tissue and isolate individual vessel elements. These improved techniques are suitable to observe the intact morphology of vascular bundles in the grape, improve experimental efficiency and accelerate new discoveries on the anatomical structure of the grape.
文摘This study investigates the paleodepositional conditions of the No.6 Seam of the Madzaringwe Formation in Makhado and Voorburg south area of the Soutpansberg Coalfield(Limpopo Province,South Africa)utilizing organic petrography and inorganic geochemical proxies.The coals are predominantly high-volatile bituminous B-A rank with high ash yields(avg.36.1 wt%),characterized by high-vitrinite(~41.5 vol%),moderate-to-high inertinite(9.8 vol%–33.7 vol%)and low liptinite(~2.3 vol%).The distribution of inertinite varies among different coal horizons(from bottom-lower to middle-upper),suggesting differential oxidation conditions and/or paleofire occurrence.Vitrinite-to-inertinite(V/I)ratio,tissue preservation–gelification index(TPI–GI),and groundwater–vegetation index(GWI–VI)plots,indicate that the peat-forming forest-swamp vegetation accumulated under mesotrophic-to-rheotrophic hydrological conditions.The presence of structured macerals(i.e.,telinite,collotelinite,fusinite,and semifusinite)suggests well-preserved plant tissues,whereas framboidal pyrite and sulphur content(0.24 wt%–2.16 wt%)point to brackish-water influence at the peat stage.The coals contain quartz,kaolinite,siderite,muscovite,dolomite,calcite,and pyrite minerals,most of which were likely sourced from felsic igneous rocks.The Al/(Al+Fe+Mn)and(Fe+Mn)/Ti ratios for the studied samples range between 0.24–0.97 and 0.57–70.10,respectively.The ratios,Al–Fe–Mn plot,and presence of massive botryoidal-type pyrite imply some influence of meteoric waters or fluids from hydrothermal activity post-deposition.Moreover,the chemical index of alteration(CIA:98.25–99.67),chemical index of weathering(CIW:92.04–97.66),and A–CN–K ternary diagram suggest inorganic matter suffered strong chemical weathering,indicating warm paleoclimatic conditions during the coal formation.
文摘The hydrocarbon generation potential of the Campano-Maastrichtian to Paleogene shales from the Benin Flank(located in SW Nigeria)of the Anambra Basin,has been previously investigated mostly by studying outcrops and by relatively few subsurface data-based studies.Thus,it is expedient undertaking an assessment of the hydrocarbon generation potential of this frontier area from subsurface samples.Campano-Maastrichtian to Paleogene shale samples obtained from Egoli-1 borehole in the Benin Flank of the Anambra Basin are studied by means of HAWK programmed pyrolysis,organic petrography,and mineralogy(XRD),with the aim to explore the petroleum-generating potential and the thermal maturity.The obtained results display a significant variation of the TOC content ranging from very low(<0.5%)to significant(>5%),indicating poor to excellent oil potential based on S_(2)values under the condition,of course,the studied formations reached the oil window.The shales of the Nsukka and Imo Formations display lower petroleum-generating potential than these of the Mamu Formation.All the studied samples are dominated by gas-prone(type III)and inert(type IV)kerogens,with few displaying mixed II/III(oil-and gas-prone).The organic-petrography observations support partly the results of the HAWK programmed pyrolysis,as they reveal an organic-richer Mamu Formation in comparison to the Nsukka and Imo Formations;huminite/vitrinite particles(both indigenous and recycled)along with variable contents of liptinite(mostly alginite and bituminite)and inertinite macerals(mostly inertodetrinite)are hosted in the shales.The latter display a typical composition for fine-grained clastic sediments;mostly kaolinite,illite/montmorillonite,quartz,and subordinately,anatase.In terms of thermal maturity,huminite/vitrinite reflectance data points to immature stage;however,the occurrence of solid bitumens,displaying equivalent vitrinite reflectance values within the oil window,points to an active petroleum system in sequences deeper than the examined ones.
文摘Knowing that flavored products would increase the use of olive oil by non-traditional consumers and enhance the added value of this valuable agricultural product,the virgin olive oil(VOO)was flavored with the seeds of Pimpinella anisum(Green anise)using three different methods:classic maceration,ultrasonic assisted maceration and direct addition of the essential oil(EO).These methodswere compared under two main criteria:time and level of aromatization.The physico-chemical parameters and the thermal stability of flavored oils prepared by the three methods were determined by AOAC titration method and GC–MS analysis so as to compare the aromatization effect of the three methods.The trans-anethole is the major component of the EO of anise seeds as well as the indicator of the level of aromatization.GC/MS analysis results of the flavored oils showed that the diffusion of trans-anethole in the flavored oil by direct addition of EO was very important(36.3%of the total volatile fraction of the flavored oil)in comparison to the oil flavored by ultrasonic assisted maceration or classic maceration(respectively 26.59%and 23.85%).These different aromatization methods ensure an improvement in the quality of VOO with an enrichment in polyphenols estimated at 35%in the case of ultrasonic flavored oil,an increase in the content of carotenoids and chlorophylls(67%and 21%respectively)in the event of aromatization by classic maceration,and a decrease in specific absorbency at 232 nmestimated at 29%during aromatization by addition of EO as well as a decrease in the peroxide value estimated at 26%in oil flavored by classic maceration unlike in oil flavored by ultrasoundwhich has seen an increase of around 20%.The aromatization was able to maintain the stability of the oils and its qualification as VOO with a gain in induction time in the case of treatment at 60℃ estimated at 29 and 27.5 d respectively in oils flavored by addition of EO and by conventional maceration,an improvement resistance to degradation concerning K_(232) and K_(270) of all flavored oils which varied from 15 to 40 d in the case of treatment at 60℃ and 3 h resistance to degradation of oils treated at 130℃ for K_(232).Polyphenols,chlorophyll pigments and carotenoids play an important role in oxidative stability due to their antioxidant nature and their degradation during heating is very complex.All of these physico-chemical changes have increased the thermal stability of flavored oils with better resistance to oxidation of flavored oil by classic maceration in compared to oil flavored by adding EO and the oil flavored by using ultrasound.
基金Supported by A Grant-in-Aid for Scientific Research from the Japanese Ministry of Education,Science and Sports,No.24240076
文摘AIM: To facilitate close contacts between transplanted cardiomyocytes and host skeletal muscle using cell fusion mediated by hemagglutinating virus of Japan envelope(HVJ-E) and tissue maceration. METHODS: Cardiomyocytes(1.5 × 106) from fetal rats were first cultured. After proliferation, some cells were used for fusion with adult muscle fibers using HVJ-E. Other cells were used to create cardiomyocyte sheets(area: about 3.5 cm2 including 2.1 × 106 cells), which were then treated with Nile blue, separated, and transplanted between the latissimus dorsi and intercostal muscles of adult rats with four combinations of HVJ-E and/or Na OH maceration: G1: HVJ-E(+), Na OH(+), Cardiomyocytes(+); G2: HVJ-E(-), NaO H(+), Cardiomyocytes(+); G3: HVJ-E(+),Na OH(-), Cardiomyocytes(+); G4: HVJ-E(-), Na OH(-), Cardiomyocytes(-). At 1 and 2 wk after transplantation, the four groups were compared by detection of beating domains, motion images using moving target analysis software, action potentials, gene expression of MLC-2v and Mesp1 by reverse transcription-polymerase chain reaction, hematoxylin-eosin staining, and immunostaining for cardiac troponin and skeletal myosin.RESULTS: In vitro cardiomyocytes were fused with skeletal muscle fibers using HVJ-E. Cardiomyocyte sheets remained in the primary transplanted sites for 2 wk. Although beating domains were detected in G1, G2, and G3 rats, G1 rats prevailed in the number, size, motion image amplitudes, and action potential compared with G2 and G3 rats. Close contacts were only found in G1 rats. At 1 wk after transplantation, the cardiomyocyte sheets showed adhesion at various points to the myoblast layer in the latissimus dorsi muscle. At 2 wk after transplantation, close contacts were seen over a broad area. Part of the skeletal muscle sarcoplasma seemed to project into the myocardiocyte plasma and some nuclei appeared to share both sarcoplasmas.CONCLUSION: The present results show that close contacts were acquired and facilitated the beating function, thereby providing a new cellular transplantation method using HVJ-E and NaO H maceration.
文摘The effect of lanthanum on the growth and extracellular enzyme activity of Erwinia chrysanthemi(Ech) was studied. Lanthanum inhibited the growth of Ech in solid culture at the concentration of 50, 100, 150, 200, 250, 300 and 350 mgL-1, and the inhibition increased with the increase of the RE concentration. The formation of colony delayed and the diameter of colony decreased. Lanthanum stimulated the growth of Ech within 24h when the lanthanum concentration was less than 200 mgL-1 in liquid medium, but significantly inhibited the growth of Ech with the increase of lanthanum concentration and culture time. When the concentration was higher than 350 mgL-1, the growth of Ech was inhibited completely both in solid and liquid culture. The extracellular enzyme acitivity of Ech was affected by lanthanum at 200 mgL-1. The activity of cellulose was promoted more than that of protease but the activity of pectinase was decreased. The maceration to potato tuber tissue decreased when the cell free filtrate was tr
文摘AIM To examine the efficacy of three extraction techniques: Soxhlet-extraction(SE), cold-maceration(CM) and microwave-assisted-extraction(MAE) using 80% methanol as solvent. METHODS The study was performed on each of 50 g of Vernonia amygdalina(VA) and Occimum gratissimum(OG) leaves respectively. The percentage yield, duration of extraction, volume of solvent used, qualitative and quantitative phytoconstituents present was compared. The biological activities(hypoglycemic effect) were investigated using albino wistar rat model of diabetes mellitus(n = 36) with a combined dose(1:1) of the two plants leaf extracts(250 mg/kg b.w.) from the three methods. Theextracts were administered orally, once daily for 21 d.RESULTS In this report, the percentage VA extract yield from MAE was highest(20.9% ± 1.05%) within 39 min using 250 m L of solvent, when compared to the CM(14.35% ± 0.28%) within 4320 min using 900 m L of solvent and SE(15.75% ± 0.71%) within 265 min using 500 m L of solvent. The percentage differences in OG extract yield between: MAE vs SE was 41.05%; MAE vs CM was 46.81% and SE vs CM was 9.77%. The qualitative chemical analysis of the two plants showed no difference in the various phytoconstituents tested, but differs quantitatively in the amount of the individual phytoconstituents, as MAE had significantly high yield(P > 0.05) on phenolics, saponins and tannins. SE technique gave significantly high yield(P > 0.05) on alkaloid, while CM gave significant high yield on flavonoids. The extracts from CM exhibited a significantly(P > 0.05) better hypoglycemic activity within the first 14-d of treatment(43.3% ± 3.62%) when compared to MAE(36.5% ± 0.08%) and SE methods(33.3% ± 1.60%). However, the percentage hypoglycemic activity, 21 d post-treatment with 250 mg/kg b.w. extract from MAE was 72.6% ± 1.03% and it was more comparable to 10 mg/kg b.w. glibenclamide treated group(75.0% ± 0.73%), unlike the SE(69.5% ± 0.71%) and CM(69.1% ± 1.03%). CONCLUSION CM technique produces extract with better hypoglycemic activity, whereas; MAE is a better option for high yield of phytoconstituents using less solvent within a short time.
文摘Background: Artemisia afra is an indigenous plant used in Africa. It is used in traditional medicine to treat a variety of diseases caused by bacterial infections. As a result, developing innovative therapeutic methods using natural ingredients to combat pathogenic germs is critical. Methodology: Artemisia afra leaves were extracted using maceration extraction utilizing three solvents (petroleum ether, ethanol, and dichloromethane). Fresh leaves were extracted using hydrodistillation. The agar well diffusion method was used to test the crude extract and essential oil leaves of Artemisia afra against different human pathogenic bacteria strains (E. coli, S. aureus, E. faecalis, and K. pneumonia) at different concentrations in the presence of a positive (ciprofloxacin 5.0 μg) and negative (DMSO) control. Results: Artemisia afra revealed the presence of alkaloids, flavonoids, tannins, saponins, anthraquinones, terpenoids, coumarins, phenolic quinones, cardiac glycosides, and steroids. It showed that the highest antibacterial activity given by the ethanol extract had highly inhibition zones against gram-positive and gram-negative bacteria. The essential oil extract was effective against all tested bacteria. Conclusion: Plant crude extracts and essential oils may have antibacterial properties due to the synergistic activity of two or more active secondary metabolites.
文摘<strong>Background:</strong><span style="font-family:;" "=""> <i>Celosia laxa (</i>Amaranthaceae) is mainly a west African plant species used in Traditional Medicine as an anthelmintic, anticancer, antibacterial and analgesic agent. The seeming prevalence of worm infection in Gwandu </span><span style="font-family:;" "="">community of Gwandu Local Government Area of Kebbi State-Nigeria</span><span style="font-family:;" "=""> prompted this study. <b>Methods:</b><i> </i>Whole plant of <i>C. laxa</i> extracts obtained through maceration in aqueous (AE), methanol (ME) and hexane (HE) solvents were investi</span><span style="font-family:;" "="">gated for their anthelmintic activity against Indian earthworms (<i>Pheretima posthuman) </i>at four different (gradient) concentrations of<i> </i>10, 20, 40 and 8<span>0 (mg/ml) for each extract. The study involved the determination of time of paralysis (P) and time of death (D) of the worms. <b>Results:</b> Both the aqueous and ethanolic extracts exhibited significant anthelmintic activity at the highest con</span>centration of 80 mg/ml as compared to the standard drug, praziquantel (10</span><span style="font-family:;" "=""> </span><span style="font-family:;" "="">mg/ml). Consequently, the aqueous extract showed a higher activity at 80</span><span style="font-family:;" "=""> </span><span style="font-family:;" "="">mg/ml compared to standard praziquantel at 10</span><span style="font-family:;" "=""> </span><span style="font-family:;" "="">mg/ml (with no significant value of p</span><span style="font-family:;" "=""> </span><span style="font-family:;" "=""><</span><span style="font-family:;" "=""> </span><span style="font-family:;" "="">0.05). The time of paralysis and death observed for AE was 13.0 ± 1.8 and 16.8 ± 1.5 while the ME was less bioactive with 15.7 ± 0.5 and 23.0 ± 0.0 respectively. However, on the other hand, the hexane extract recorded no-activity on all the test</span><span style="font-family:;" "=""> </span><span style="font-family:;" "="">sample concentrations, compared</span><span style="font-family:;" "=""> to </span><span style="font-family:;" "="">the standard drug (with a significant difference of p-value, p</span><span style="font-family:;" "=""> </span><span style="font-family:;" "="">></span><span style="font-family:;" "=""> </span><span style="font-family:;" "="">0.05). <b>Conclusion:</b> It was concluded that the leaves of <i>C. laxa</i> </span><span style="font-family:;" "="">are</span><span style="font-family:;" "=""> likely to yield a potent anthelminthic drug owing to soluble phytoconstituent which are largely hydrophilicity extracted by the polar solvents. Also, considering that the plants’ mode of preparation for use by the locals was aqueous decoction before administration, the folkloric therapeutic claims can be said to have been justified.</span>
基金Supported by the National Engineering Labo-ratory of Direct Coal Liquefaction(MZY-16).
文摘In this research,molecular structure models were developed respectively for Shenhua coal vitrinite concentrates(SDV)and inertinite concentrates(SDI),on the basis of information on constitutional unit of Shenhau coal and elemental analysis results obtained from^(13)C-NMR analysis characterization,FTIR analysis characterization,X-ray diffraction XRD and XPS analysis characterization.It can be observed from characterization data and molecular structure models that the structure of SDV and SDI is dominated by aromatic hydrocarbon,with aromaticity of SDI higher than that of SDV;SDV mainly consists of small molecule basic structure unit,while SDI is largely made from macromolecular structure unit.Based on bond-level parameters of the molecular model,the research found through the autoclave experiment that vitrinite liquefaction process goes under thermodynamics control and inertinite liquefaction process under dynamics control.The research developed an efficient directional direct coal liquefaction technology based on the maceral characteristics of Shenhua coal,which can effectively improve oil yield and lower gas yield.
文摘This paper discussed the petrographic characteristics of No.6 coal from the Xiaoyugou mine,Jungar Coalfield,Ordos Basin,China.10 samples(7 coal,1 parting mudstone and 2 floor mudstone)were analysed by microscopical and geochemical methods.Four maceral compositions and several associated elements parameters were selected as indicators and corresponding diagrams were drawn to explicate the sedimentary environment.The results indicate that the maceral is dominated by vitrinite and minerals are mainly kaolinite in the No.6 coal.The sedimentary facies vary from barrier island system to tidal-flat which is a deposition process of water body shallowing and the coal-forming plants are herbs and woody plants formed in swamps.
基金supported by the National Natural Science Foundation of China(41030213)the Major National S&T Program of China(2011ZX05033-002 and 2011ZX05009-002)the Fundamental Research Funds for the Central Universities in China(2010YD09)
文摘Inertinite maceral compositions of the Late Permian coals from three sections in the terrestrial and paralic settings of eastern Yunnan are analyzed in order to reveal the paleo-fire events and the atmospheric oxygen levels in the latest Permian. Although the macerals in the studied sections are generally dominated by vitrinite, the inertinite group makes up a considerable proportion. Its content increases upward from the beginning of the Late Permian to the coal seam near the Permian- Triassic boundary. Based on the microscopic features and the prevailing theory that inertinite is largely a by-product of paleo-fires, we suggest that the increasing upward trend of the inertinite abundance in the latest Permian could imply that the Late Permian peatland had suffered from frequent wildfires. Since ignition and burning depend on sufficient oxygen, a model-based calculation suggests that the 02 levels near the Wuchiapingian/Changhsingian boundary and the Permian-Triassic boundary are 27% and 28% respectively. This output adds supports to other discoveries made in the temporal marine and terrestrial sediments, and challenges the theories advocating hypoxia as a mechanism for the PermianTriassic boundary crisis.
文摘This study presents a review of the various methods to predict the spontaneous combustion liability of coal and coal-shale. The relative propensity of coal to undergo self-heating can be established by different methods. These methods are well established in their usage, but the fact that no particular test method has become a standard to predict the spontaneous combustion liability indicates that doubt still exists as to the validity of all of them. The underlying principle of all the tests is that the more readily the coal undergoes exothermic oxidation, the more liable it is to self-heat. Comprehensive studies that centres on the international position on research being conducted by academics, different research institutes and industries on spontaneous combustion of coal and coal mine fires were evaluated. Relationships between the geochemical analysis (proximate and ultimate analysis, forms of sulphur, petrographic properties, X-ray diffraction and X-ray fluorescence) and spontaneous combustion testing methods (numerical and experimental approaches) used to predict the spontaneous combustion liability of coal were reviewed. The combination of these tests provides a better understanding of the mechanism that controls the spontaneous combustion phenomena. However, irrespective of the extensive studies that have been conducted over time, spontaneous combustion is still a major problem in the coal value chain.
基金supported by the National Natural Science Foundation of China(U2003125)。
文摘The filtration and dewatering of fine clean coal not only ensure industrial water recycle in coal washing plant,but also reduce the moisture of coal product in order to meet the requirements of combustion or coking industry.Fine clean coal is mainly composed by organic matter,and the property difference of different organic matter determines the filtration and dewatering behavior.In this investigation,vitrinite and inertinite were separated from a clean bituminous coal,and the comparative filtration and dewatering behavior of vitrinite and inertinite were conducted.The results showed that inertinite has lower dewatering rate and higher filter cake moisture than vitrinite.The analysis of filter cake structure showed that inertinite particle is easier to be broken into small particles due to the difference of mechanical properties,thus forming more compact filter cake than vitrinite.The analysis of particle surface properties showed that vitrinite is more hydrophobic than inertinite,which makes water easier drained from filter cake.The simulation study showed that the structure of inertinite is more porous than that of vitrinite,and the interaction between inertinite and water is stronger than that between vitrinite and water.This study provides a theoretical basis for improving coal dewatering by selectively improving coal maceral hydrophobicity.
基金the financial supports by the National Basic Research Program of China(No.2012CB214905)the National Natural Science Foundation of China(No.51274198)the Graduate Education Innovation Project of Jiangsu Province of China(No.CXLX12_0966)
文摘The objective of this paper is to evaluate the coal petrology characteristics of slack middlings(13–0.5 mm)of dense media separation and flotation middlings from Qianjiaying fat coal preparation plant.Phase composition,macerals distribution,microlithotype and mineral occurrence of the two middlings were studied by XRD analysis and polarized light microscopy observation.Macerals distribution and wettability of the float-and-sink products separated from the middlings after grinding was investigated to determine the liberation degree.Studies show that there are more vitrinite and mineral,but less inertinite in slack middlings than in flotation middlings.Macerals associated with mineral in slack middlings is 69.85%,by volume,which is 17.86%higher than that in flotation middlings.Minerals in slack middlings are dominated by pyrite and clay,which are disseminated with the diameter less than2 lm.The main mineral in flotation middlings is clay with size range of 2–20 lm.Single macerals in the slack middlings are diffcult to liberate due to the fne-grained minerals.After grinding,macerals associated with minerals in the slack middlings decrease to 46.73%,by volume,which is higher than in flotation middlings by 25.89%,by volume.For slack middlings with poor liberation degree,density fractions below1.8 g/cm3is hydrophobic with contact angle above 71.5°.For the well liberated flotation middlings,there is signifcant wettability difference among the float-and-sink products.This research is the theoretical basis to realize re-separation of middlings.
文摘The distribution and verticals variation of geochemical components in the Kasnau-Matasukh lignites of Nagaur Basin, Rajasthan, were investigated using microscopy, proximate and ultimate analyses, Rock-Eval Pyrolysis, X-ray diffraction and Fourier Transform Infrared analyses, and major/minor/trace element determination. The relationship of elements with ash content and with macerals have also been discussed. These lignites are stratified, black, dominantly composed of huminite group macerals with subordinated amounts of liptinite and inertinite groups. They are classified as type-III kerogen and are mainly gas prone in nature. The concentration (in vol%) of mineral matter is seen to increase towards upper part of seam and so is the concentration (in wt%) of the volatile matter, elemental carbon and sulphur. The common minerals present in these lignitesare mixed clay layer, chlorite, and quartz as identified by X-ray diffraction study. Compared with world average in brown coal, the bulk concentration of Cu is anomalously high in most of the samples while Cd is 2-3 times high and Zn is high in one band. Based on interrelationship, different pyrite forms are noticed to have different preferential enrichment of various elements. The concentration of disseminated pyrite is more than the other pyrite forms and is followed by discrete pyrite grains and massive pyrite.
文摘Lignite samples collected from Vastan, Rajpardi and Tadkeshwar lignite mines of Cambay basin (Gujarat) were subjected to organic petrographic investigations and geochemical analyses and the data, thus generated, is used to reconstruct the paleodepositional history of these lignite sequences. The lignites of Cambay basin dominantly comprise huminite maceral group (71.6%-86.3%) followed by liptinite (10.1%-19.3%) and inertinite (3.6%-11.0%) maceral groups. The mineral matter varies from 9.0% to 20.0%. The petrography based facies model indicates that these lignites have high values of gelification index (GI) and low tissue preservation index revealing a continuous wet condition in the basin and a relatively slower rate of subsidence during the decay of organic matter. On several occasions, during the formation of seams in Tadkeshwar, Rajpardi and Vastan mines, the value of GI exceeded 10 which indicates a forest permanently flooded and the cause of pronounced degree of degradation. However, few sections in Tadkeshwar seam had relatively drier spells of environmental conditions due to fluctuation in the water table as revealed by moderately high content of inertinite macerals. This is specially indicated by the occurrence of funginite which normally thrives in the upper oxy- genated peatigenic layer and indicates prevalence of oxic conditions during plant deposition. Such conditions prevailed during a transgressive phase but there were intermittent fluvial activities also giving rise to supratidal flood plain as reflected in the form of associated carbonaceous shales in the basin.
文摘The pyrolysis characteristics of Shendong Shangwan coal and its macerals concentrate were investigated using thermogravimetry (TG) coupled with mass spectrometry (MS). The evolved gases were analyzed online by MS spectroscopy. The results of TG/DTG (derivative thermogravimetry) show ths vitrinite concentrate has greater weight loss rate and higher volatile yield than the other two samples. More light hydrocarbons C1-C5 are released from the vitfinite concentrate than from the Shendong Shangwan coal and inertinite concentrated in the process of pyrolysis. Three samples have similar shape curves of evolved gases of C2~C5 with different intensities. When the pyrolysis temperature was lower than 418℃, the amount of C6H6 evolved in the process of pyrolysis of inertinite concentrated was higher than that of raw coal and vitrinite concentrate. As the temperature rising, the production rate of C6H6 increased. Below 672℃, C6H6 evolution rate of vitrinite concentrate was far greater than the other two samples; the main evolution temperature range of C7H8 was 400℃ to 700℃ for the three samples. The amount of HE and H20 released first increased and then decreased with the temperature increase while more H2 released for pyrolysis of inertinite concentrated and more H20 released for the pyrolysis of vitrinite concentrate.
基金supported by Chinese Ministry of Science and Technology Project(No.2006CB202202)the National Natural Science Foundation of China(No.40972106 and No.40772095)
文摘Multiple sets of thick coal beds characterized by simple structure and shallow burial depth were developed in the Early and Middle Jurassic strata of the Ordos Basin, northwestern China. The huge reserves of this high quality coal have a high commercial value. We studied the coal's petrologic characteristics and its maceral distribution to determine the maceral's contribution to generation of oil and gas. The results show that the Jurassic coals in the Ordos Basin have special petrological features because of the Basin's unique depo- sitional environment which was mainly a series of high-stand swamps in the upper fluvial system. These petro- graphic features are a result of the development of typical inland lakes where some sand bodies were formed by migrating rivers. After burial, the peat continued to undergo oxidizing conditions, this process generated extensive higher inertinite contents in the coals and the vitrinite components were altered to semi-vitrinite. The macroscopic petrographic types of these Jurassic coals are mainly semi-dull coal, dull coal, semilustrous and lustrous coal. The proportions of semi-dull coal and dull coal are higher in the basin margins, especially in the area near the northern margin. The numbers of semilustrous and lustrous coals increase southwards and towards the central basin. This situation indicates that different coal-forming swamp environments have major controlling effects on the coal components. Another observation is that in the Ordos' coal sequences, especially in the lower part, some sandstone beds are thick, up to 20 m with a coarse grain size. The higher fusinite content in the macerals accompanies a higher semi-vitrinite content with more complete and regular plant cell structure. The fusinite structure is clear and well preserved. After burial, the lithology of the roof and floor rocks can continue to affect the evolution of coal petrology. The sand bodies in the roof and floor exhibit good physical conditions so that pore water can maintain a long-term state of oxidation, circulation and connection to the coal. So coal components remain in an oxidation environment for a long time. Conversely, in the basin center, lacustrine facies developed and peat was rapidly covered by mudstone after burial and subsequent coal beds rapidly entered a reducing environment. As a result, abundant gelatification occurred and the vitrinite content increased. E^inite often accumulated in a specific position in the coal bed. Although the average exinite content is not high on the whole, it does significantly contribute to the total hydrocarbon generation. The exinite content has been underestimated, especially the amorphous bituminous fluid and its importance is emphasized here. The reason is that the fluid flows easily into fusinite which has strong rigidity, or flows into some fissures, where it is commonly neglected.