In order to comprehend the applicability of microwave irradiation for recovering coalbed methane,it is necessary to evaluate the microwave irradiation-induced alterations in coals with varying levels of metamorphism.I...In order to comprehend the applicability of microwave irradiation for recovering coalbed methane,it is necessary to evaluate the microwave irradiation-induced alterations in coals with varying levels of metamorphism.In this work,the carbon molecular sieve combined with KMnO_(4)oxidation was selected to fabricate carbon molecular sieve with diverse oxidation degrees,which can serve as model substances toward coals.Afterwards,the microwave irradiation dependences of pores,functional groups,and highpressure methane adsorption characteristics of model substances were studied.The results indicated that microwave irradiation causes rearrangement of oxygen-containing functional groups,which could block the micropores with a size of 0.40-0.60 nm in carbon molecular sieve;meanwhile,naphthalene and phenanthrene generated by macro-molecular structure pyrolysis due to microwave irradiation could block the micropores with a size of 0.70-0.90 nm.These alterations in micropore structure weaken the saturated methane adsorption capacity of oxidized carbon molecular sieve by 2.91%-23.28%,suggesting that microwave irradiation could promote methane desorption.Moreover,the increased mesopores found for oxidized carbon molecular sieve after microwave irradiation could benefit CH4 diffusion.In summary,the oxidized carbon molecular sieve can act as model substances toward coals with different ranks.Additionally,microwave irradiation is a promising technology to enhance coalbed methane recovery.展开更多
Theabrownins(TBs)are the characteristic functional and quality components of dark teas such as Pu’er tea and Chin-brick tea.TBs are a class of water-soluble brown polymers with multi-molecular weight distribution pro...Theabrownins(TBs)are the characteristic functional and quality components of dark teas such as Pu’er tea and Chin-brick tea.TBs are a class of water-soluble brown polymers with multi-molecular weight distribution produced by the oxidative polymerisation of tea polyphenols during the fermentation process of dark tea,both enzymatically and non-enzymatically.TBs have been extracted and purified from dark tea all the time,but the obtained TBs contain heterogeneous components such as polysaccharides and caffeine in the bound state,which are difficult to remove.The isolation and purification process was tedious and required the use of organic solvents,which made it difficult to industrialise TBs.In this study,epigallocatechin(EGC),epigallocatechin gallate(EGCG),epigallocatechin gallate(ECG),EGC/EGCG(mass ratio 1:1),EGCG/ECG(mass ratio 1:1),EGC/ECG(mass ratio 1:1)and EGC/EGCG/ECG(mass ratio 1:1:1)as substrates and catalyzed by polyphenol oxidase(PPO)and peroxidase(POD)in turn to produce TBs,named TBs-dE-1,TBs-dE-2,TBs-dE-3,TBs-dE-4,TBs-dE-5,TBs-dE-6 and TBs-dE-7.The physicochemical properties and the antibacterial activity and mechanism of TBs-dE-1–7 were investigated.Sensory and colour difference measurements showed that all seven tea browning samples showed varying degrees of brownish hue.Zeta potential in aqueous solutions at pH 3.0–9.0 indicated that TBs-dE-1–7 was negatively charged and the potential increased with increasing pH.The characteristic absorption peaks of TBs-dE-1–7 were observed at 208 and 274 nm by UV-visible(UV-vis)scanning spectroscopy.Fourier transform infrared(FT-IR)spectra indicated that they were phenolic compounds.TBs-dE-1–7 showed significant inhibition of Escherichia coli DH5α(E.coli DH5α).TBs-dE-3 showed the strongest inhibitory effect with minimum inhibitory concentration(MIC)of 1.25 mg mL–1 and MBC of 10 mg mL–1,followed by TBs-dE-5 and TBs-dE-6.These three TBs-dEs were selected to further investigate their inhibition mechanism.The TBs-dE was found to damage the extracellular membrane of E.coli DH5α,causing leakage of contents,and increase intracellular reactive oxygen content,resulting in abnormal cell metabolism due to oxidative stress.The results of the study provide a theoretical basis for the industrial preparation and product development of TBs.展开更多
Iron deficiency anemia(IDA)is a major global health problem.Tegillarca granosa has been considered as an excellent source of iron given its high content of iron-binding protein,ferritin.The aim of the present study wa...Iron deficiency anemia(IDA)is a major global health problem.Tegillarca granosa has been considered as an excellent source of iron given its high content of iron-binding protein,ferritin.The aim of the present study was to determine the physicochemical properties,protein structures,and iron uptake of ferritin extracted from T.granosa,and to evaluate the potential impacts of chitosan glycosylation on these characteristics.Based on Box-Behnken design and response surface methodology,the optimal conditions for glycosylation included a ferritin/chitosan mass ratio of 4:1,a pH of 5.5,a reaction time of 10 min,and a reaction temperature of 50℃.Glycosylation caused decreased surface hydrophobicity and elevated water-holding capacity of ferritin due to the introduction of hydrophilic groups.Additionally,glycosylation improved antioxidant capacity of ferritin by 20.69%–189.66%,likely owing to the protons donated by saccharide moiety to terminate free radical chain reaction.The in vitro digestibility of ferritin was elevated by 22.56%–104.85%after glycosylation,which could be associated with lessβ-sheet content in secondary structure that made the glycosylated protein less resistant to enzymatic digestion.The results of the iron bioavailability in Caco-2 cells revealed that ferritin(78.85–231.77 ngmg^(−1))exhibited better iron bioavailability than FeSO4(51.48–114.37 ngmg^(−1))and the values were further elevated by glycosylation with chitosan(296.23–358.20 ngmg^(−1)),which may be related to the physicochemical properties of ferritin via glycosylation modification.These results provide a basis for the development of T.granosa derived ferritin and its glycosylated products,and can promote the utilization of aquatic resources.展开更多
Crop rotation periodicity has always been one of the research focuses currently. In this study, the physicochemical properties, nutrient contents and enzyme activities were investigated in soils from rice-cherry tomat...Crop rotation periodicity has always been one of the research focuses currently. In this study, the physicochemical properties, nutrient contents and enzyme activities were investigated in soils from rice-cherry tomato rotation for one year (1a), three years (3a), five years (5a), seven years (7a) and ten years (10a), respectively. The major objective was to analyze the optimal rotation years of rice-cherry tomato from soil perspective, so as to provide theoretical basis for effectively avoiding continuous cropping obstacles of cherry tomato via studying the response characteristics of soil physicochemical properties, nutrient contents and enzyme activities to planting years of rice-cherry tomato rotation system. The results were as follows: 1) Soil pH value was increased year by year during 1a to 5a, reached the highest value 5.32 at 5a. However, soil acidity was sharply enhanced during 7a to 10a (P P •kg<sup>-1</sup> at 5a. 3) The content of soil available phosphorus was increased year by year with increasing of crop rotation years, and increased by 110% to 173% during 3a to 10a (P P P < 0.05). In conclusion, long-term single rotation pattern of rice-cherry tomato would aggravate soil acidification, prompt soil nutrient imbalance and reduce soil enzyme activity. 5a to 7a would be the appropriate rotation period for rice-cherry tomato, or else it would reduce soil quality, resulting in a new continuous cropping obstacle of cherry tomato.展开更多
The development of advanced air transportation has raised new demands for high-performance liquid hydrocarbon fuels.However,the measurement of fuel properties is time-consuming,cost-intensive,and limited to the operat...The development of advanced air transportation has raised new demands for high-performance liquid hydrocarbon fuels.However,the measurement of fuel properties is time-consuming,cost-intensive,and limited to the operating conditions.The physicochemical properties of aerospace fuels are directly infl uenced by chemical composition.Thus,a thorough investigation should be conducted on the inherent relationship between fuel properties and composition for the design and synthesis of high-grade fuels and the prediction of fuel properties in the future.This work summarized the eff ects of fuel composition and hydrocarbon molecular structure on the fuel physicochemical properties,including density,net heat of combustion(NHOC),low-temperature fl uidity(viscosity and freezing point),fl ash point,and thermal-oxidative stability.Several correlations and predictions of fuel properties from chemical composition were reviewed.Additionally,we correlated the fuel properties with hydrogen/carbon molar ratios(n H/C)and molecular weight(M).The results from the least-square method implicate that the coupling of H/C molar ratio and M is suitable for the estimation of density,NHOC,viscosity and eff ectiveness for the design,manufacture,and evaluation of aviation hydrocarbon fuels.展开更多
Soil microorganisms and physicochemical properties are considered the two most influencing factors for maintaining plant diversity.However,the operational mechanisms and which factor is the most influential manipulato...Soil microorganisms and physicochemical properties are considered the two most influencing factors for maintaining plant diversity.However,the operational mechanisms and which factor is the most influential manipulator remain poorly understood.In this study,we examine the collaborative influences of soil physicochemical properties(i.e.,soil water,soil organic matter(SOM),salinity,total phosphorus and nitrogen,pH,soil bulk density and fine root biomass)and soil microorganisms(fungi and bacteria)on plant diversity across two types of tree patches dominated by big and small trees(big trees:height≥7 m and DBH≥60 cm;small trees:height≤4.5 m and DBH≤20 cm)in an arid desert region.Tree patch is consists of a single tree or group of trees and their accompanying shrubs and herbs.It was hypothesized that soil physicochemical properties and microorganisms affect plant diversity but their influence differ.The results show that plant and soil microbial diversity increased with increasing distances from big trees.SOM,salinity,fine root biomass,soil water,total phosphorus and total nitrogen contents decreased with increasing distance from big trees,while pH and soil bulk density did not change.Plant and soil microbial diversity were higher in areas close to big trees compared with small trees,whereas soil physicochemical properties were opposite.The average contribution of soil physicochemical properties(12.2%-13.5%)to plant diversity was higher than microbial diversity(4.8%-6.7%).Salinity had the largest negative affect on plant diversity(24.7%-27.4%).This study suggests that soil fungi constrain plant diversity while bacteria improve it in tree patches.Soil physicochemical properties are the most important factor modulating plant diversity in arid desert tree patches.展开更多
A major challenge in modern rice production is to achieve the dual goals of high yield and good quality with low environmental costs.This study was designed to determine whether optimized nitrogen(N)fertilization coul...A major challenge in modern rice production is to achieve the dual goals of high yield and good quality with low environmental costs.This study was designed to determine whether optimized nitrogen(N)fertilization could fulfill these multiple goals.In two-year experiments,two high yielding‘super’rice cultivars were grown with different N fertilization management regimes,including zero N input,local farmers’practice(LFP)with heavy N inputs,and optimized N fertilization(ONF).In ONF,by reducing N input,increasing planting density,and optimizing the ratio of urea application at different stages,N use efficiency and the physicochemical and textural properties of milled rice were improved at higher yield levels.Compared with LFP,yield and partial factor productivity of applied N(PFP)under ONF were increased(on average)by 1.70 and 13.06%,respectively.ONF increased starch and amylose content,and significantly decreased protein content.The contents of the short chains of A chain(degree of polymerization(DP)6-12)and B1 chain(DP 13-25)of amylopectin were significantly increased under ONF,which resulted in a decrease in the stability of rice starch crystals.ONF increased viscosity values and improved the thermodynamic properties of starch,which resulted in better eating and cooking quality of the rice.Thus,ONF could substantially compensate the negative effects caused by N fertilizer and achieve the multiple goals of higher grain quality and nitrogen use efficiency(NUE)at high yield levels.These results will be useful for applications of high quality rice production at high yield levels.展开更多
The physicochemical properties of the system, such as density, surface tension, specific conductance and melting point were measured. The results were discussed.
[ Objective] To understand the physicochemical properties of musk deer pneumonia and purulent disease viruses. [ Method] The pneu- monia and purulent disease viruses were isolated from the abnormal and purulent lung t...[ Objective] To understand the physicochemical properties of musk deer pneumonia and purulent disease viruses. [ Method] The pneu- monia and purulent disease viruses were isolated from the abnormal and purulent lung tissues of musk deer. Then the isolated viruses were inocula- ted into the Vero cells. After culturing, the virus solution was collected and used to determine TCID50 and genoma types. The sensitivity to fat sol- vent, resistance to hydrochloric acid and trypsin as well as tolerance to heat of the musk deer pneumonia and purulent disease viruses were detec- ted, respectively. [ Result] The obvious cytopathic effects (CPE) were found in Veto cells infected by the isolated viruses. The virus was 2-1.43 TCID50/ml and its genome was RNA. The virus was not sensitive to chloroform, 1% trypsin and heats, and it had a certain tolerance to 0.1 mol/L hy- drochloric acid. [ Conclusion] The study on the physicochemical properties of musk deer pneumonia and purulent disease viruses lays a foundation for prevention and control of the musk deer pneumonia and purulent diseases.展开更多
Moringa oleifera is a plant that successfully grows recently in Egypt and has rich of nutrients seeds with valuable content of edible oil. The present study aimed at determining the physicochemical properties of morin...Moringa oleifera is a plant that successfully grows recently in Egypt and has rich of nutrients seeds with valuable content of edible oil. The present study aimed at determining the physicochemical properties of moringa seeds and their extracted oil of which cultivated at different regions in Egypt. Obtained results revealed that protein, lipid, ash, fiber and total carbohydrate contents were in range of 34.51% - 36.5%, 28.62% - 30.06%, 4.22% - 5.06%, 10.92% - 12.16% and 19.00% - 20.29%, respectively. Consequently, caloric value was around 450.36 - 451.32 kcal 100 g<sup>-1</sup> for dried moringa seeds. As confirmed, dried moringa seeds are considered as a rich source of dietary minerals. TPCs content of M. oleifera seed were ranged from 16.9 - 18.5 mg GAE g<sup>-1</sup> dw. The anti-oxidants activity was in a range of 0.17 - 0.28 μmol TE g<sup>-1</sup> dw (DPPH scavenging activity) and was in a range of 4.19 - 6.29 μmol TE g<sup>-1</sup> dw (DPPH scavenging activity). The chlorophyll a, chlorophyll b, carotenoids, flavonoids and flavonols contents were ranged from 0.93 to 1.78, 4.89 to 8.41, 13.53 to 19.56 mg g<sup>-1</sup> dw, 3.30 to 5.40 and 2.30 to 4.10 mg QE g<sup>-1</sup> dw, respectively. Obviously, the individual essential amino acids (EAAs) and nonessential amino acids (NEAAs) recorded higher contents when compared to referenced protein. Total AA showed in triple amount in moringa protein when compared FAO standard. The acid value, iodine value, unsaponificable matter, peroxide value, refractive index, saponification value of cold pressed moringa seeds oil found to be 0.29 - 0.37 mg·g<sup>-1</sup>, 65.7 - 67.5, 0.60 to 0.74 g 100 g<sup>-1</sup>, 1.67 - 2.47 mEq/Kg, 1.4607 - 1.4613, 171.7 to 178.3 mg KOH g<sup>-1</sup>, respectively. Clearly, the unsaturated fatty acids (USFA) contents of M. oleifera edible oils were 77.14% - 84.98%, especially oleic (73.30% - 79.58%). On the contrary, the saturated fatty acids (SFA) recorded 15.00% - 22.83% where palmitic and stearic acids were the predominant SFA. The results of oil physicochemical parameters were compared with those of commercial oils. It could be illustrated that moringa seeds and its oil considered as a good source for dietary nutraceuticals and valuable characteristics for potential nutritional and technological applications.展开更多
Microorganisms in permafrost can live in cold environments due to coadapted physicochemical processes in this environment. In this paper, the relation between microbial number and soil physicochemical properties at th...Microorganisms in permafrost can live in cold environments due to coadapted physicochemical processes in this environment. In this paper, the relation between microbial number and soil physicochemical properties at the headwaters area of the Urumqi River is analyzed by using fluorescence microscopy counting and oligo-culture techniques. In total, 20 samples from a 200-cm permafrost core were used as study materials. The study reveals that the number of culturable bacteria has a significantly positive correlation with soil water content, total carbon and total nitrogen concentrations, and a significantly negative correlation with soil pH value. In addition, the ratio of culturable bacteria to total cell number decreases with depths. The results demonstrate that the number of culturable bacteria in permafrost is closely correlated with soil physicochemical properties and depositional age.展开更多
Spinel lithium manganese oxide cathode materials were synthesized using the ultrasonic-assisted sol-gel method. The synthesized samples were investigated by differential thermal analysis (DTA) and thermogravimetry ...Spinel lithium manganese oxide cathode materials were synthesized using the ultrasonic-assisted sol-gel method. The synthesized samples were investigated by differential thermal analysis (DTA) and thermogravimetry (TG), powder X-ray diffraction (XRD), scanning electron microscopy (SEM), cyclic voltammetry (CV), and the charge-discharge test. TG-DTA shows that significant mass loss occurs in two temperature regions during the synthesis of LiLa0.01Mn1.9903.99F0.01. XRD data indicate that all samples exhibit the same pure spinel phase, and LiLa0.01Mn1.9903.99F0.01 and LiLa0.01Mn1.9904 samples have a better crystallinity than LiMn2O4. SEM images indicate that LiLa0.01Mn1.9903.99F0.01 has a slightly smaller particle size and a more regular morphology structure with narrow size distribution. The charge-discharge test reveals that the initial capacities of LiMn2O4, LiLa0.01Mn1.99O4, and LiLa0.01Mn1.99O3.99F0.01 are 130, 123, and 126 mAh·g^-1, respectively, and the capacity retention rates of the initial value, after 50 cycles, are 84.8%, 92.3%, and 92.1%, respectively. The electrode coulomb efficiency and CV reveal that the electrode synthesized by the ultrasonic-assisted sol-gel (UASG) method has a better re- versibility than the electrode synthesized by the sol-gel method.展开更多
The pulsed corona discharge(CD)generated in contact with water and directly in water,and high-power air plasma jet(APJ)were studied for production of plasma activated water(PAW).The changes of physical(pH,redox potent...The pulsed corona discharge(CD)generated in contact with water and directly in water,and high-power air plasma jet(APJ)were studied for production of plasma activated water(PAW).The changes of physical(pH,redox potential,conductivity,temperature)and chemical(peroxides,nitrites,nitrates concentrations)properties of treated water were investigated.The comparison of CD generated in gas/water interface and underwater configuration in the same system showed that the interaction of reactive oxygen and nitrogen species formed in ambient air in gas/water system induces different chemical processes,leading to lower pH,higher oxidation-reduction potential(ORP)and higher conductivity of PAW than in underwater discharge.High yield of peroxide was observed in both configurations.The PAW prepared by APJ exhibits high concentration of nitrites and nitrates according to supplied energy,and related significant decrease of pH and increase of ORP and conductivity after treatment.The antimicrobial effect of PAW prepared by CD and plasma jet on lentils sprouts was studied in different treatment and washing times.The APJ appears to have great efficacy on water activation resulted in strong decontamination effect.The PAW treated by APJ for 10 min led to bacterial reduction from initial 8.3 to 5.9 and 4.0 log10 CFU g^(-1)after 10 and 30 min of washing,respectively.展开更多
Objective:To study physicochemical properties,antioxidant and anti-inflammatory activities of coumarin-carbonodithioate hybrids.Methods:The substituted 4-bromomethyl coumarins were synthesized in first step by the cyc...Objective:To study physicochemical properties,antioxidant and anti-inflammatory activities of coumarin-carbonodithioate hybrids.Methods:The substituted 4-bromomethyl coumarins were synthesized in first step by the cyclization.Then the reaction of substituted coumarins(a-e)with potassium O-ethyl/methyl carbonodithioate(1)by using absolute ethanol as solvent,afforded coumarin-carbonodithioate(1a-1j)derivatives under microwave irradiation and the conventional method.The spectroscopic analysis was used for the characterization of coumarin derivatives.The title(1a-1j)compounds were confirmed by spectroscopic methods.Antioxidant property was evaluated by using DPPH free radical-scavenging ability assay method and anti-inflammatory activity was evaluated by protein denaturation procedure using diclofenac sodium as a standard.Drug-likeness.In-silico toxicity was predicted with LD_(50)value and bioactivity score was also calculated for all the compounds.Results:All coumarin(1a-1j)compounds exhibited promisingin-vitro antioxidant and anti-inflammatory properties in comparison to standard drugs.All tested compounds were used for evaluating their physicochemical properties as set by Lipinski rule.It was observed that the synthesized compounds followed rule of five,indicating more'drug-like'nature.Conclusions:All the screened coumarin-carbonodithioates display promising in vitro antioxidant and antiinflammatory activities.From the physicochemical properties of coumarin derivatives,it is found that none of the compounds violate the Lipinski rule and they fall well in the range of rule of five.It is concluded that the coumarin-carbonodithioate hybrids act with more'drug-like'nature.展开更多
Soil sample plots were specified and the soil in layer A0, A1 and AB were collected in Maoershan-Forest Experiment Farm of Northeast Forestry University for study of the effect of corylus clusters on soil in 1999. The...Soil sample plots were specified and the soil in layer A0, A1 and AB were collected in Maoershan-Forest Experiment Farm of Northeast Forestry University for study of the effect of corylus clusters on soil in 1999. The result shows that the pH value, contents of organic matter, total nitrogen, alkali-discomposed nitrogen and total phosphorus under the corylus clusters are higher than that under the non-corylus clusters, except the available phosphorus content. The number of soil granular aggregates or the water stable aggregates under corylus clusters is more than that under the non-corylus clusters. The corylus clusters play an important role in improving the physicochemical properties of the soil, which should be conserved and developed in the forestry production.展开更多
[Objectives]This study was conducted to explore the differences in physicochemical properties and surface properties of biochar from different sources.[Methods]Four kinds of materials including rice husk and corn stra...[Objectives]This study was conducted to explore the differences in physicochemical properties and surface properties of biochar from different sources.[Methods]Four kinds of materials including rice husk and corn straw were prepared at 450℃by the limited-oxygen program temperature control method into biochar,and the differences in physicochemical properties and surface properties of the biochar from different sources were studied.[Results]All four kinds of biochar were alkaline(pH=8.7-10.0).Corn straw biochar had the highest organic carbon content(653.6 g/kg),while rice husk biochar had the lowest organic carbon content(486.1 g/kg).Corn straw biochar had the highest nitrogen content(2.7%),while rice husk biochar had the lowest nitrogen content(0.75%).Corn straw biochar had the highest total phosphorus content(5.64 g/kg),while rice husk biochar had the lowest total phosphorus content(1.1 g/kg).Rice straw biochar had the highest total potassium content(53.1 g/kg),while rice husk biochar had the lowest total potassium content(10.6 g/kg).The four types of biochar were all porous,but their pore structure sizes and shapes were different to certain degrees.The order of the specific surface areas of the four types of biochar was rice stalk biochar>corn stalk biochar>wheat stalk biochar>rice husk biochar;the order of the pore volumes was rice stalk biochar>corn stalk biochar>wheat stalk biochar Charcoal>rice husk biochar;and the pore sizes ranked as wheat stalk biochar>corn stalk biochar>rice husk biochar>rice stalk biochar.The biochar from different sources ranked according to the comprehensive evaluation of all indicators as corn straw biochar>wheat straw biochar>rice straw biochar>rice husk biochar.[Conclusions]This study provides reference data for the preparation process of biochar from industrial and agricultural wastes and its application and promotion.展开更多
The routine nutrients, mineral content, amino acid content and fatty acid content as well as the physicochemical properties and the heavy metal and pesticide residues of Iongissimus dorsi muscles in confined Dazu blac...The routine nutrients, mineral content, amino acid content and fatty acid content as well as the physicochemical properties and the heavy metal and pesticide residues of Iongissimus dorsi muscles in confined Dazu black goats at the age of 6 months were determined. The results showed that the lamb meat of Dazu black goats was dch in nutrients, fresh, tender, palatable and fine in texture as well as non-hazardous in quality. Thus, the meat of Dazu black goat is a kind of healthy and nutritious food with rich nutrients, and it has better prospects of exploitation and utilization in the food industry.展开更多
[Objective]The research aimed to understand the change rules of physicochemical properties of soil in the different modes of returning farmland to forest.[Method]The physicochemical properties of soil in three differe...[Objective]The research aimed to understand the change rules of physicochemical properties of soil in the different modes of returning farmland to forest.[Method]The physicochemical properties of soil in three different types of returning farmland to forest(Hippophae rhamnoides Linn.forest,Caragana korshinskii forest and Ulmus pumila L.forest)were analyzed by taking the enclosed grassland as comparison in Bashang area of northern Hebei Province.[Result]The results showed that there were significant differences among different types.Order of the bulk density of soil:H.rhamnoides Linn.forest(1.17 g/cm^3)<U.pumila L.forest(1.24 g/cm^3)<C.korshinskii forest(1.26 g/cm^3)<enclosed grassland(1.61 g/cm^3);order of the total porosity of soil:H.rhamnoides Linn.forest(55.29%)>U.pumila L.forest(52.55%)>C.korshinskii forest(51.93%)<enclosed grassland(38.85%);order of the organic matter content of soil:H.rhamnoides Linn.forest(3.191%)>C.korshinskii forest(3.128%)>U.pumila L.forest(2.804%)>enclosed grassland(2.536%).[Conclusion]After returning farmland to forest,vegetation played a positive role in physicochemical properties of soil.There were significant differences in physicochemical properties of soil among different modes of returning farmland to forest,and the improvement effect of H.rhamnoides Linn.forest on physicochemical properties of soil was the best.展开更多
The remarkable push of technologies increasingly recommends materials for their constructions.Hence the extraction of alumina is for different uses.The exploitation of bauxite pollutes the surrounding areas in this ca...The remarkable push of technologies increasingly recommends materials for their constructions.Hence the extraction of alumina is for different uses.The exploitation of bauxite pollutes the surrounding areas in this case the discharge of mud wheel.Furthermore,the excessive use of dangerous conventional synthetic insecticides continues to be in circulation in Cameroon despite the known adverse effects.These problems lead us to formulate bio insecticides from rejection of the extraction of alumina and extracts of S.aromaticum and Citrus sinensis which respectively offer us essential oils eugenol and limonene having insecticidal properties against the main insects,pests of corn stocks,Sitophilus zeamais.From the kinetic point of view of the adsorption of the extracts of eugenol,limonene and their association by the red mud,the adsorption curve shows that the Eu/Li mixture(30/70)is better by 0.36 mg/g during the 24 h.The results showed a high toxicity of the Eu-Li binary mixture of ratio 30/70 with respective mortality rates of 95.88%after 8 days of exposure to the concentration of 5 mL/L on the adults of Sitophilus zeamais.The other composites induce an average rate of 80%.The results from the physicochemical analysis of corn before and after treatment with formulated insecticides showed a slight loss in nutritional quality of 14.90%in ash,12.5%in protein,16.14%in lipids and 13.63%in total sugars for 180 days.The powdery formulation from red mud and Eu-Li(30/70)mixture can therefore ensure the protection of corn stocks against Sitophilus zeamais in a farming environment.展开更多
基金supported by the National Natural Science Foundation of China(42272202 and 52264001)the Yunnan Fundamental Research Projects(202201AT070144)+1 种基金the Yunnan Ten Thousand Talents Plan Young&Elite Talents Project(YNWRQNBJ-2019-164)Training Programmes of Innovation and Entrepreneurship for Undergraduates of Yunnan Province(S202210674128).
文摘In order to comprehend the applicability of microwave irradiation for recovering coalbed methane,it is necessary to evaluate the microwave irradiation-induced alterations in coals with varying levels of metamorphism.In this work,the carbon molecular sieve combined with KMnO_(4)oxidation was selected to fabricate carbon molecular sieve with diverse oxidation degrees,which can serve as model substances toward coals.Afterwards,the microwave irradiation dependences of pores,functional groups,and highpressure methane adsorption characteristics of model substances were studied.The results indicated that microwave irradiation causes rearrangement of oxygen-containing functional groups,which could block the micropores with a size of 0.40-0.60 nm in carbon molecular sieve;meanwhile,naphthalene and phenanthrene generated by macro-molecular structure pyrolysis due to microwave irradiation could block the micropores with a size of 0.70-0.90 nm.These alterations in micropore structure weaken the saturated methane adsorption capacity of oxidized carbon molecular sieve by 2.91%-23.28%,suggesting that microwave irradiation could promote methane desorption.Moreover,the increased mesopores found for oxidized carbon molecular sieve after microwave irradiation could benefit CH4 diffusion.In summary,the oxidized carbon molecular sieve can act as model substances toward coals with different ranks.Additionally,microwave irradiation is a promising technology to enhance coalbed methane recovery.
基金financially supported by the National Natural Science Foundation of China(31871813).
文摘Theabrownins(TBs)are the characteristic functional and quality components of dark teas such as Pu’er tea and Chin-brick tea.TBs are a class of water-soluble brown polymers with multi-molecular weight distribution produced by the oxidative polymerisation of tea polyphenols during the fermentation process of dark tea,both enzymatically and non-enzymatically.TBs have been extracted and purified from dark tea all the time,but the obtained TBs contain heterogeneous components such as polysaccharides and caffeine in the bound state,which are difficult to remove.The isolation and purification process was tedious and required the use of organic solvents,which made it difficult to industrialise TBs.In this study,epigallocatechin(EGC),epigallocatechin gallate(EGCG),epigallocatechin gallate(ECG),EGC/EGCG(mass ratio 1:1),EGCG/ECG(mass ratio 1:1),EGC/ECG(mass ratio 1:1)and EGC/EGCG/ECG(mass ratio 1:1:1)as substrates and catalyzed by polyphenol oxidase(PPO)and peroxidase(POD)in turn to produce TBs,named TBs-dE-1,TBs-dE-2,TBs-dE-3,TBs-dE-4,TBs-dE-5,TBs-dE-6 and TBs-dE-7.The physicochemical properties and the antibacterial activity and mechanism of TBs-dE-1–7 were investigated.Sensory and colour difference measurements showed that all seven tea browning samples showed varying degrees of brownish hue.Zeta potential in aqueous solutions at pH 3.0–9.0 indicated that TBs-dE-1–7 was negatively charged and the potential increased with increasing pH.The characteristic absorption peaks of TBs-dE-1–7 were observed at 208 and 274 nm by UV-visible(UV-vis)scanning spectroscopy.Fourier transform infrared(FT-IR)spectra indicated that they were phenolic compounds.TBs-dE-1–7 showed significant inhibition of Escherichia coli DH5α(E.coli DH5α).TBs-dE-3 showed the strongest inhibitory effect with minimum inhibitory concentration(MIC)of 1.25 mg mL–1 and MBC of 10 mg mL–1,followed by TBs-dE-5 and TBs-dE-6.These three TBs-dEs were selected to further investigate their inhibition mechanism.The TBs-dE was found to damage the extracellular membrane of E.coli DH5α,causing leakage of contents,and increase intracellular reactive oxygen content,resulting in abnormal cell metabolism due to oxidative stress.The results of the study provide a theoretical basis for the industrial preparation and product development of TBs.
基金supported by the National Key R&D Program of China(No.2018YFD0901105).
文摘Iron deficiency anemia(IDA)is a major global health problem.Tegillarca granosa has been considered as an excellent source of iron given its high content of iron-binding protein,ferritin.The aim of the present study was to determine the physicochemical properties,protein structures,and iron uptake of ferritin extracted from T.granosa,and to evaluate the potential impacts of chitosan glycosylation on these characteristics.Based on Box-Behnken design and response surface methodology,the optimal conditions for glycosylation included a ferritin/chitosan mass ratio of 4:1,a pH of 5.5,a reaction time of 10 min,and a reaction temperature of 50℃.Glycosylation caused decreased surface hydrophobicity and elevated water-holding capacity of ferritin due to the introduction of hydrophilic groups.Additionally,glycosylation improved antioxidant capacity of ferritin by 20.69%–189.66%,likely owing to the protons donated by saccharide moiety to terminate free radical chain reaction.The in vitro digestibility of ferritin was elevated by 22.56%–104.85%after glycosylation,which could be associated with lessβ-sheet content in secondary structure that made the glycosylated protein less resistant to enzymatic digestion.The results of the iron bioavailability in Caco-2 cells revealed that ferritin(78.85–231.77 ngmg^(−1))exhibited better iron bioavailability than FeSO4(51.48–114.37 ngmg^(−1))and the values were further elevated by glycosylation with chitosan(296.23–358.20 ngmg^(−1)),which may be related to the physicochemical properties of ferritin via glycosylation modification.These results provide a basis for the development of T.granosa derived ferritin and its glycosylated products,and can promote the utilization of aquatic resources.
文摘Crop rotation periodicity has always been one of the research focuses currently. In this study, the physicochemical properties, nutrient contents and enzyme activities were investigated in soils from rice-cherry tomato rotation for one year (1a), three years (3a), five years (5a), seven years (7a) and ten years (10a), respectively. The major objective was to analyze the optimal rotation years of rice-cherry tomato from soil perspective, so as to provide theoretical basis for effectively avoiding continuous cropping obstacles of cherry tomato via studying the response characteristics of soil physicochemical properties, nutrient contents and enzyme activities to planting years of rice-cherry tomato rotation system. The results were as follows: 1) Soil pH value was increased year by year during 1a to 5a, reached the highest value 5.32 at 5a. However, soil acidity was sharply enhanced during 7a to 10a (P P •kg<sup>-1</sup> at 5a. 3) The content of soil available phosphorus was increased year by year with increasing of crop rotation years, and increased by 110% to 173% during 3a to 10a (P P P < 0.05). In conclusion, long-term single rotation pattern of rice-cherry tomato would aggravate soil acidification, prompt soil nutrient imbalance and reduce soil enzyme activity. 5a to 7a would be the appropriate rotation period for rice-cherry tomato, or else it would reduce soil quality, resulting in a new continuous cropping obstacle of cherry tomato.
基金This work was supported by the Scientific Research Projects of the Ministry of Education of China(6141A02033522)the National Natural Science Foundation of China(No.21978200).
文摘The development of advanced air transportation has raised new demands for high-performance liquid hydrocarbon fuels.However,the measurement of fuel properties is time-consuming,cost-intensive,and limited to the operating conditions.The physicochemical properties of aerospace fuels are directly infl uenced by chemical composition.Thus,a thorough investigation should be conducted on the inherent relationship between fuel properties and composition for the design and synthesis of high-grade fuels and the prediction of fuel properties in the future.This work summarized the eff ects of fuel composition and hydrocarbon molecular structure on the fuel physicochemical properties,including density,net heat of combustion(NHOC),low-temperature fl uidity(viscosity and freezing point),fl ash point,and thermal-oxidative stability.Several correlations and predictions of fuel properties from chemical composition were reviewed.Additionally,we correlated the fuel properties with hydrogen/carbon molar ratios(n H/C)and molecular weight(M).The results from the least-square method implicate that the coupling of H/C molar ratio and M is suitable for the estimation of density,NHOC,viscosity and eff ectiveness for the design,manufacture,and evaluation of aviation hydrocarbon fuels.
基金This work was supported fi nancially by National Natural Science Foundation of China(Grant Nos.and 41,871,031 and 31,860,111)Natural Science Foundation of Xinjiang(Grant No.2017D01C080).
文摘Soil microorganisms and physicochemical properties are considered the two most influencing factors for maintaining plant diversity.However,the operational mechanisms and which factor is the most influential manipulator remain poorly understood.In this study,we examine the collaborative influences of soil physicochemical properties(i.e.,soil water,soil organic matter(SOM),salinity,total phosphorus and nitrogen,pH,soil bulk density and fine root biomass)and soil microorganisms(fungi and bacteria)on plant diversity across two types of tree patches dominated by big and small trees(big trees:height≥7 m and DBH≥60 cm;small trees:height≤4.5 m and DBH≤20 cm)in an arid desert region.Tree patch is consists of a single tree or group of trees and their accompanying shrubs and herbs.It was hypothesized that soil physicochemical properties and microorganisms affect plant diversity but their influence differ.The results show that plant and soil microbial diversity increased with increasing distances from big trees.SOM,salinity,fine root biomass,soil water,total phosphorus and total nitrogen contents decreased with increasing distance from big trees,while pH and soil bulk density did not change.Plant and soil microbial diversity were higher in areas close to big trees compared with small trees,whereas soil physicochemical properties were opposite.The average contribution of soil physicochemical properties(12.2%-13.5%)to plant diversity was higher than microbial diversity(4.8%-6.7%).Salinity had the largest negative affect on plant diversity(24.7%-27.4%).This study suggests that soil fungi constrain plant diversity while bacteria improve it in tree patches.Soil physicochemical properties are the most important factor modulating plant diversity in arid desert tree patches.
基金financially supported by the National Natural Science Foundation of China (32071943 and 31872853)the Priority Academic Program Development of Jiangsu Higher Education Institutions, China (PAPD)
文摘A major challenge in modern rice production is to achieve the dual goals of high yield and good quality with low environmental costs.This study was designed to determine whether optimized nitrogen(N)fertilization could fulfill these multiple goals.In two-year experiments,two high yielding‘super’rice cultivars were grown with different N fertilization management regimes,including zero N input,local farmers’practice(LFP)with heavy N inputs,and optimized N fertilization(ONF).In ONF,by reducing N input,increasing planting density,and optimizing the ratio of urea application at different stages,N use efficiency and the physicochemical and textural properties of milled rice were improved at higher yield levels.Compared with LFP,yield and partial factor productivity of applied N(PFP)under ONF were increased(on average)by 1.70 and 13.06%,respectively.ONF increased starch and amylose content,and significantly decreased protein content.The contents of the short chains of A chain(degree of polymerization(DP)6-12)and B1 chain(DP 13-25)of amylopectin were significantly increased under ONF,which resulted in a decrease in the stability of rice starch crystals.ONF increased viscosity values and improved the thermodynamic properties of starch,which resulted in better eating and cooking quality of the rice.Thus,ONF could substantially compensate the negative effects caused by N fertilizer and achieve the multiple goals of higher grain quality and nitrogen use efficiency(NUE)at high yield levels.These results will be useful for applications of high quality rice production at high yield levels.
文摘The physicochemical properties of the system, such as density, surface tension, specific conductance and melting point were measured. The results were discussed.
基金supported by the Youth Fund Projects of Sichuan Education Department(07ZB060)Technology Support Projects of Sichuan Science and Technology Department(2009SZ0228)
文摘[ Objective] To understand the physicochemical properties of musk deer pneumonia and purulent disease viruses. [ Method] The pneu- monia and purulent disease viruses were isolated from the abnormal and purulent lung tissues of musk deer. Then the isolated viruses were inocula- ted into the Vero cells. After culturing, the virus solution was collected and used to determine TCID50 and genoma types. The sensitivity to fat sol- vent, resistance to hydrochloric acid and trypsin as well as tolerance to heat of the musk deer pneumonia and purulent disease viruses were detec- ted, respectively. [ Result] The obvious cytopathic effects (CPE) were found in Veto cells infected by the isolated viruses. The virus was 2-1.43 TCID50/ml and its genome was RNA. The virus was not sensitive to chloroform, 1% trypsin and heats, and it had a certain tolerance to 0.1 mol/L hy- drochloric acid. [ Conclusion] The study on the physicochemical properties of musk deer pneumonia and purulent disease viruses lays a foundation for prevention and control of the musk deer pneumonia and purulent diseases.
文摘Moringa oleifera is a plant that successfully grows recently in Egypt and has rich of nutrients seeds with valuable content of edible oil. The present study aimed at determining the physicochemical properties of moringa seeds and their extracted oil of which cultivated at different regions in Egypt. Obtained results revealed that protein, lipid, ash, fiber and total carbohydrate contents were in range of 34.51% - 36.5%, 28.62% - 30.06%, 4.22% - 5.06%, 10.92% - 12.16% and 19.00% - 20.29%, respectively. Consequently, caloric value was around 450.36 - 451.32 kcal 100 g<sup>-1</sup> for dried moringa seeds. As confirmed, dried moringa seeds are considered as a rich source of dietary minerals. TPCs content of M. oleifera seed were ranged from 16.9 - 18.5 mg GAE g<sup>-1</sup> dw. The anti-oxidants activity was in a range of 0.17 - 0.28 μmol TE g<sup>-1</sup> dw (DPPH scavenging activity) and was in a range of 4.19 - 6.29 μmol TE g<sup>-1</sup> dw (DPPH scavenging activity). The chlorophyll a, chlorophyll b, carotenoids, flavonoids and flavonols contents were ranged from 0.93 to 1.78, 4.89 to 8.41, 13.53 to 19.56 mg g<sup>-1</sup> dw, 3.30 to 5.40 and 2.30 to 4.10 mg QE g<sup>-1</sup> dw, respectively. Obviously, the individual essential amino acids (EAAs) and nonessential amino acids (NEAAs) recorded higher contents when compared to referenced protein. Total AA showed in triple amount in moringa protein when compared FAO standard. The acid value, iodine value, unsaponificable matter, peroxide value, refractive index, saponification value of cold pressed moringa seeds oil found to be 0.29 - 0.37 mg·g<sup>-1</sup>, 65.7 - 67.5, 0.60 to 0.74 g 100 g<sup>-1</sup>, 1.67 - 2.47 mEq/Kg, 1.4607 - 1.4613, 171.7 to 178.3 mg KOH g<sup>-1</sup>, respectively. Clearly, the unsaturated fatty acids (USFA) contents of M. oleifera edible oils were 77.14% - 84.98%, especially oleic (73.30% - 79.58%). On the contrary, the saturated fatty acids (SFA) recorded 15.00% - 22.83% where palmitic and stearic acids were the predominant SFA. The results of oil physicochemical parameters were compared with those of commercial oils. It could be illustrated that moringa seeds and its oil considered as a good source for dietary nutraceuticals and valuable characteristics for potential nutritional and technological applications.
基金supported by the National Natural Science Foundation of China(Grant Nos. 30800154,31170465,31100365, 40971034)the China Postdoctoral Science Fund(Grant No.20080430794)
文摘Microorganisms in permafrost can live in cold environments due to coadapted physicochemical processes in this environment. In this paper, the relation between microbial number and soil physicochemical properties at the headwaters area of the Urumqi River is analyzed by using fluorescence microscopy counting and oligo-culture techniques. In total, 20 samples from a 200-cm permafrost core were used as study materials. The study reveals that the number of culturable bacteria has a significantly positive correlation with soil water content, total carbon and total nitrogen concentrations, and a significantly negative correlation with soil pH value. In addition, the ratio of culturable bacteria to total cell number decreases with depths. The results demonstrate that the number of culturable bacteria in permafrost is closely correlated with soil physicochemical properties and depositional age.
文摘Spinel lithium manganese oxide cathode materials were synthesized using the ultrasonic-assisted sol-gel method. The synthesized samples were investigated by differential thermal analysis (DTA) and thermogravimetry (TG), powder X-ray diffraction (XRD), scanning electron microscopy (SEM), cyclic voltammetry (CV), and the charge-discharge test. TG-DTA shows that significant mass loss occurs in two temperature regions during the synthesis of LiLa0.01Mn1.9903.99F0.01. XRD data indicate that all samples exhibit the same pure spinel phase, and LiLa0.01Mn1.9903.99F0.01 and LiLa0.01Mn1.9904 samples have a better crystallinity than LiMn2O4. SEM images indicate that LiLa0.01Mn1.9903.99F0.01 has a slightly smaller particle size and a more regular morphology structure with narrow size distribution. The charge-discharge test reveals that the initial capacities of LiMn2O4, LiLa0.01Mn1.99O4, and LiLa0.01Mn1.99O3.99F0.01 are 130, 123, and 126 mAh·g^-1, respectively, and the capacity retention rates of the initial value, after 50 cycles, are 84.8%, 92.3%, and 92.1%, respectively. The electrode coulomb efficiency and CV reveal that the electrode synthesized by the ultrasonic-assisted sol-gel (UASG) method has a better re- versibility than the electrode synthesized by the sol-gel method.
基金supported by the Slovak Research and Development Agency under the contract Nos.APVV-16-0216,APVV-19-0386 and Slovak Grant Agency No.1/0782/19。
文摘The pulsed corona discharge(CD)generated in contact with water and directly in water,and high-power air plasma jet(APJ)were studied for production of plasma activated water(PAW).The changes of physical(pH,redox potential,conductivity,temperature)and chemical(peroxides,nitrites,nitrates concentrations)properties of treated water were investigated.The comparison of CD generated in gas/water interface and underwater configuration in the same system showed that the interaction of reactive oxygen and nitrogen species formed in ambient air in gas/water system induces different chemical processes,leading to lower pH,higher oxidation-reduction potential(ORP)and higher conductivity of PAW than in underwater discharge.High yield of peroxide was observed in both configurations.The PAW prepared by APJ exhibits high concentration of nitrites and nitrates according to supplied energy,and related significant decrease of pH and increase of ORP and conductivity after treatment.The antimicrobial effect of PAW prepared by CD and plasma jet on lentils sprouts was studied in different treatment and washing times.The APJ appears to have great efficacy on water activation resulted in strong decontamination effect.The PAW treated by APJ for 10 min led to bacterial reduction from initial 8.3 to 5.9 and 4.0 log10 CFU g^(-1)after 10 and 30 min of washing,respectively.
文摘Objective:To study physicochemical properties,antioxidant and anti-inflammatory activities of coumarin-carbonodithioate hybrids.Methods:The substituted 4-bromomethyl coumarins were synthesized in first step by the cyclization.Then the reaction of substituted coumarins(a-e)with potassium O-ethyl/methyl carbonodithioate(1)by using absolute ethanol as solvent,afforded coumarin-carbonodithioate(1a-1j)derivatives under microwave irradiation and the conventional method.The spectroscopic analysis was used for the characterization of coumarin derivatives.The title(1a-1j)compounds were confirmed by spectroscopic methods.Antioxidant property was evaluated by using DPPH free radical-scavenging ability assay method and anti-inflammatory activity was evaluated by protein denaturation procedure using diclofenac sodium as a standard.Drug-likeness.In-silico toxicity was predicted with LD_(50)value and bioactivity score was also calculated for all the compounds.Results:All coumarin(1a-1j)compounds exhibited promisingin-vitro antioxidant and anti-inflammatory properties in comparison to standard drugs.All tested compounds were used for evaluating their physicochemical properties as set by Lipinski rule.It was observed that the synthesized compounds followed rule of five,indicating more'drug-like'nature.Conclusions:All the screened coumarin-carbonodithioates display promising in vitro antioxidant and antiinflammatory activities.From the physicochemical properties of coumarin derivatives,it is found that none of the compounds violate the Lipinski rule and they fall well in the range of rule of five.It is concluded that the coumarin-carbonodithioate hybrids act with more'drug-like'nature.
文摘Soil sample plots were specified and the soil in layer A0, A1 and AB were collected in Maoershan-Forest Experiment Farm of Northeast Forestry University for study of the effect of corylus clusters on soil in 1999. The result shows that the pH value, contents of organic matter, total nitrogen, alkali-discomposed nitrogen and total phosphorus under the corylus clusters are higher than that under the non-corylus clusters, except the available phosphorus content. The number of soil granular aggregates or the water stable aggregates under corylus clusters is more than that under the non-corylus clusters. The corylus clusters play an important role in improving the physicochemical properties of the soil, which should be conserved and developed in the forestry production.
基金General Project of Chongqing Technology Innovation and Application Demonstration(Social People s Livelihood)(cstc2018jscx-msybX0215)Science and Technology Planning Project of Kaizhou District,Chongqing City(KZKJ-2020-J-10).
文摘[Objectives]This study was conducted to explore the differences in physicochemical properties and surface properties of biochar from different sources.[Methods]Four kinds of materials including rice husk and corn straw were prepared at 450℃by the limited-oxygen program temperature control method into biochar,and the differences in physicochemical properties and surface properties of the biochar from different sources were studied.[Results]All four kinds of biochar were alkaline(pH=8.7-10.0).Corn straw biochar had the highest organic carbon content(653.6 g/kg),while rice husk biochar had the lowest organic carbon content(486.1 g/kg).Corn straw biochar had the highest nitrogen content(2.7%),while rice husk biochar had the lowest nitrogen content(0.75%).Corn straw biochar had the highest total phosphorus content(5.64 g/kg),while rice husk biochar had the lowest total phosphorus content(1.1 g/kg).Rice straw biochar had the highest total potassium content(53.1 g/kg),while rice husk biochar had the lowest total potassium content(10.6 g/kg).The four types of biochar were all porous,but their pore structure sizes and shapes were different to certain degrees.The order of the specific surface areas of the four types of biochar was rice stalk biochar>corn stalk biochar>wheat stalk biochar>rice husk biochar;the order of the pore volumes was rice stalk biochar>corn stalk biochar>wheat stalk biochar Charcoal>rice husk biochar;and the pore sizes ranked as wheat stalk biochar>corn stalk biochar>rice husk biochar>rice stalk biochar.The biochar from different sources ranked according to the comprehensive evaluation of all indicators as corn straw biochar>wheat straw biochar>rice straw biochar>rice husk biochar.[Conclusions]This study provides reference data for the preparation process of biochar from industrial and agricultural wastes and its application and promotion.
基金supported by the Special Funds for Operational Costs of Basic Research Projects of Southwest University (XDJK2009C161)the Chongqing Major Science & Technology Projects"Grazing Livestock Breeding and Health Culture" (CSTC,2008AA1020 and 2008AA1019)the Research Foundation of Southwest University(08BSr09 and 08BSr11)
文摘The routine nutrients, mineral content, amino acid content and fatty acid content as well as the physicochemical properties and the heavy metal and pesticide residues of Iongissimus dorsi muscles in confined Dazu black goats at the age of 6 months were determined. The results showed that the lamb meat of Dazu black goats was dch in nutrients, fresh, tender, palatable and fine in texture as well as non-hazardous in quality. Thus, the meat of Dazu black goat is a kind of healthy and nutritious food with rich nutrients, and it has better prospects of exploitation and utilization in the food industry.
基金Supported by Science and Technology Research Project of Colleges and Universities in Hebei Province(QN2015320)Natural Science Foundation of Hebei Province(C2015101020,E2019101012)Project of Chengde Finance Bureau(CZ2013011).
文摘[Objective]The research aimed to understand the change rules of physicochemical properties of soil in the different modes of returning farmland to forest.[Method]The physicochemical properties of soil in three different types of returning farmland to forest(Hippophae rhamnoides Linn.forest,Caragana korshinskii forest and Ulmus pumila L.forest)were analyzed by taking the enclosed grassland as comparison in Bashang area of northern Hebei Province.[Result]The results showed that there were significant differences among different types.Order of the bulk density of soil:H.rhamnoides Linn.forest(1.17 g/cm^3)<U.pumila L.forest(1.24 g/cm^3)<C.korshinskii forest(1.26 g/cm^3)<enclosed grassland(1.61 g/cm^3);order of the total porosity of soil:H.rhamnoides Linn.forest(55.29%)>U.pumila L.forest(52.55%)>C.korshinskii forest(51.93%)<enclosed grassland(38.85%);order of the organic matter content of soil:H.rhamnoides Linn.forest(3.191%)>C.korshinskii forest(3.128%)>U.pumila L.forest(2.804%)>enclosed grassland(2.536%).[Conclusion]After returning farmland to forest,vegetation played a positive role in physicochemical properties of soil.There were significant differences in physicochemical properties of soil among different modes of returning farmland to forest,and the improvement effect of H.rhamnoides Linn.forest on physicochemical properties of soil was the best.
文摘The remarkable push of technologies increasingly recommends materials for their constructions.Hence the extraction of alumina is for different uses.The exploitation of bauxite pollutes the surrounding areas in this case the discharge of mud wheel.Furthermore,the excessive use of dangerous conventional synthetic insecticides continues to be in circulation in Cameroon despite the known adverse effects.These problems lead us to formulate bio insecticides from rejection of the extraction of alumina and extracts of S.aromaticum and Citrus sinensis which respectively offer us essential oils eugenol and limonene having insecticidal properties against the main insects,pests of corn stocks,Sitophilus zeamais.From the kinetic point of view of the adsorption of the extracts of eugenol,limonene and their association by the red mud,the adsorption curve shows that the Eu/Li mixture(30/70)is better by 0.36 mg/g during the 24 h.The results showed a high toxicity of the Eu-Li binary mixture of ratio 30/70 with respective mortality rates of 95.88%after 8 days of exposure to the concentration of 5 mL/L on the adults of Sitophilus zeamais.The other composites induce an average rate of 80%.The results from the physicochemical analysis of corn before and after treatment with formulated insecticides showed a slight loss in nutritional quality of 14.90%in ash,12.5%in protein,16.14%in lipids and 13.63%in total sugars for 180 days.The powdery formulation from red mud and Eu-Li(30/70)mixture can therefore ensure the protection of corn stocks against Sitophilus zeamais in a farming environment.