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FCF-LDH/BiVO_(4)with synergistic effect of physical enrichment and chemical adsorption for efficient reduction of nitrate
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作者 Yajie Bai Zhenyuan Fang +5 位作者 Yong Lei Lijing Liu Huaiquan Zhao Hongye Bai Weiqiang Fan Weidong Shi 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第7期1112-1121,共10页
Photoelectrochemical NO_(3)^(-)reduction(PEC NITRR)not only provides a promising solution for promoting the global nitrogen cycle,but also converts NO_(3)^(-)to the important chemicals(NH_(3)).However,it is still a gr... Photoelectrochemical NO_(3)^(-)reduction(PEC NITRR)not only provides a promising solution for promoting the global nitrogen cycle,but also converts NO_(3)^(-)to the important chemicals(NH_(3)).However,it is still a great challenge to prepare catalysts with excellent NO_(3)^(-)adsorption/activation capacity to achieve high NITRR.Herein,we designed a novel Fe^(2+)~Cu^(2+)Fe^(3+)LDH/BiVO_(4)(FCF-LDH/BVO)catalyst with synergistic effect of chemical adsorption and physical enrichment.Fe^(2+)in FCF-LDH/BVO provides the rich Lewis acid sites for the adsorption of NO_(3)^(-),and the appropriate layer spacing of FCF-LDH further promotes the physical enrichment of NO_(3)^(-)in its interior,thus realizing the effective contact between NO_(3)^(-)and active sites(Fe^(2+)).FCF-LDH/BVO showed excellent NH_(3)production performance(FE_(NH_(3))=66.1%,r_(NH_(3))=13.8μg h^(-1)cm^(-2))and selectivity(FE_(NO_(2)^(-))=2.5%,r_(NO_(2)^(-))=4.9μg h^(-1)cm^(-2))in 0.5 mol L^(-1)Na_(2)SO_(4)electrolyte.In addition,FCF-LDH/BVO maintains the desirable PEC stability for six cycle experiments,showing great potential for practical application.The^(14)NO_(3)^(-)and^(15)NO_(3)^(-)isotope test provides strong evidence for further verification of the origin of N in the generated NH_(3).This LDH catalyst has a great potential in PEC removal of NO_(3)^(-)from groundwater. 展开更多
关键词 LDH Lewis acid sites physical enrichment Photoelectrochemical NO_(3)^(-)Reduction Ammonia
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Functional Optical Fiber Sensors Detecting Imperceptible Physical/Chemical Changes for Smart Batteries
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作者 Yiding Li Li Wang +3 位作者 Youzhi Song Wenwei Wang Cheng Lin Xiangming He 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第8期268-308,共41页
The battery technology progress has been a contradictory process in which performance improvement and hidden risks coexist.Now the battery is still a“black box”,thus requiring a deep understanding of its internal st... The battery technology progress has been a contradictory process in which performance improvement and hidden risks coexist.Now the battery is still a“black box”,thus requiring a deep understanding of its internal state.The battery should“sense its internal physical/chemical conditions”,which puts strict requirements on embedded sensing parts.This paper summarizes the application of advanced optical fiber sensors in lithium-ion batteries and energy storage technologies that may be mass deployed,focuses on the insights of advanced optical fiber sensors into the processes of one-dimensional nano-micro-level battery material structural phase transition,electrolyte degradation,electrode-electrolyte interface dynamics to three-dimensional macro-safety evolution.The paper contributes to understanding how to use optical fiber sensors to achieve“real”and“embedded”monitoring.Through the inherent advantages of the advanced optical fiber sensor,it helps clarify the battery internal state and reaction mechanism,aiding in the establishment of more detailed models.These advancements can promote the development of smart batteries,with significant importance lying in essentially promoting the improvement of system consistency.Furthermore,with the help of smart batteries in the future,the importance of consistency can be weakened or even eliminated.The application of advanced optical fiber sensors helps comprehensively improve the battery quality,reliability,and life. 展开更多
关键词 Smart battery Advanced embedded optical fiber sensor Battery internal physical/chemical state Quality-reliability-life characteristic
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Some of the Chemical and Physical Characteristics of the Graff River in Kut City, Iraq
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作者 Salih Mahdi Ali Imad Kazem Ali 《Open Journal of Modern Hydrology》 CAS 2024年第1期56-67,共12页
Some of the chemical and physical water qualities of the Graff River in the city of Kut were studied, and for two sites of the river, One was at the Crimea site, the other in the Jihad district, and for the period fro... Some of the chemical and physical water qualities of the Graff River in the city of Kut were studied, and for two sites of the river, One was at the Crimea site, the other in the Jihad district, and for the period from October/2018 to March/2019, Seven variables of river water have been analyzed: temperature PH, electrical conductivity, TDS, turbidity, alkaline, and chloride. The results showed that most of the chemical and physical water properties of the river were in normal proportions and did not rise, except for the turbidity, which was at a very high level, and that the pH values were close to the basal side. The results of the statistical analysis revealed positive significant relationships between the pH and (chloride and TDS). On the other hand, between electrical conductivity and both previous variables as well. And a negative significant connection between temperature and alkaline. 展开更多
关键词 Graff River Kut City Iraq chemical Characteristics physical Characteristics
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Physical and Chemical Properties of Horns Sheaths Particles for the Manufacture of Composite Materials
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作者 Tawe Laynde Zakari Yaou +2 位作者 Karga Tapsia Lionel Konai Noel Danwe Raidandi 《Journal of Materials Science and Chemical Engineering》 2024年第5期1-9,共9页
Salvaged cow horns from slaughterhouses have been transformed into fine particles for a physical characterization that has led us to determine the humidity rate (2.34% ± 0.054%), the actual density situated betwe... Salvaged cow horns from slaughterhouses have been transformed into fine particles for a physical characterization that has led us to determine the humidity rate (2.34% ± 0.054%), the actual density situated between 0.586 g/cm<sup>3</sup> and 0.732 g/cm<sup>3</sup>, the swelling rate (12%), and one chemical characterization that permitted us to determine the rate of dry matters (97.05%), of mineral matters (2.5%), of protein matters (94.52%). From these weak values, it can easily be seen that cow horn case doesn’t absorb much water and improve the mechanical characteristics of the composite;the high rate of protein shows that keratin which is the structural molecule favors its gripping as reinforcing element in the manufacturing of composite materials. 展开更多
关键词 HORNS Fibers Polymer Loads physical Properties chemical Composition
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Comparative Study of Physico-Chemical and Biological Water Quality Upstream and Downstream of the Manantali Dam and Hydropower Plant from 2019 to 2023
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作者 Joseph Mbeur Faye Saïdou Ndao Louis Eugène Victor Sambou 《Journal of Geoscience and Environment Protection》 2024年第10期111-131,共21页
The comparative study is designed to monitor the physico-chemical and biological quality of the water upstream and downstream of the Manantali hydroelectric dam. The physico-chemical parameters are sampled at 3 measur... The comparative study is designed to monitor the physico-chemical and biological quality of the water upstream and downstream of the Manantali hydroelectric dam. The physico-chemical parameters are sampled at 3 measuring points located at Station 1 of the dam’s reservoir, immediately downstream of the dam and hydroelectric power station at the level of the damping basin, and at the Bafing-Bakoye confluence at Bafoulabe (Bafing side), the biological parameter (ichthyological fauna) is characterized by ichthyological inventories of landings in the various fishing camps around the reservoir and at the Mahina market (Bafing side). The study assesses the environmental impact of hydroelectric structures and facilities on the physico-chemical and biological quality of the water. Physical parameters such as temperature, conductivity, pH, turbidity and chemical parameters such as dissolved oxygen, nitrite, nitrate, manganese, hydrogen sulfide, ammonium, iron, silica and phosphorus are measured in order to identify the various variations existing between the different measurement points. Analysis of the values obtained shows very high similarities between the various measuring points, and most parameters comply with WHO standards, with the exception of turbidity, manganese, hydrogen sulfide and iron. These data attest to good water quality, allowing normal development of flora and fauna with a low level of degradation. Comparative analysis of the ichthyological fauna shows the existence of 34 species of fish belonging to 11 families at the fishing camps around the Manantali dam reservoir, and 37 species belonging to 12 families at Mahina on the Bafing River. At Mahina on the Bafing, the specific composition of the catches is characterized by the presence of the Claroteidae family and four species (Alestes sp., Brycinus leuciscus, Auchenoglanis occidentalis, Distichodus engycephalus) not recorded at the camps. In contrast, all the fish families recorded in the camps are present in Mahina, and only one species (Hydrocynus brevis) is absent from the Mahina landings. The difference in species richness could be explained by the upwelling of some fish from the Bakoye to the Bafing at the confluence. The Shannon diversity index of 4.07 at Mahina is higher than the 2.98 recorded at camp level, and the equitability index of 0.78 at Mahina and 0.58 at the camp level indicate average diversity and the non-dominance of one species over the others. The diversification index values of 3.09 and 3.08 at camp level and Mahina respectively show that the number of theoretical habitats is three. 展开更多
关键词 Manantali Dam physical Parameters chemical Parameters Fish Fauna
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Effects of Green Manure Mixed Cropping Patterns on Physical and Chemical Properties of Soil and Economic Characters of Flue-cured Tobacco 被引量:4
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作者 陈治锋 邓小华 +2 位作者 周米良 田峰 张明发 《Agricultural Science & Technology》 CAS 2015年第8期1723-1727,共5页
[Objective] The aim was to clear the suitable green manure cropping pat- terns in Xiangxi tobacco-planting areas. [Method] 8 treatments were set to study the effects of the monoculture and mixed cropping of common vet... [Objective] The aim was to clear the suitable green manure cropping pat- terns in Xiangxi tobacco-planting areas. [Method] 8 treatments were set to study the effects of the monoculture and mixed cropping of common vetch (Vicia gigantea Bge.), perennial ryegrass (Lofium) and rapeseed (Brassica campestris L.) on physi- cal and chemical properties of soil and economic characters of flue-cured tobacco. [Result] (1) Green manure turnover can reduce soil bulk density by 1.08%-8.62%, and the effect of green manure mixed cropping pattern was the best. (2) Green manure turnover also can increase the soil nutrient, soil organic matter, total nitro- gen (N), total phosphorus (P), total potassium (K), alkali-hydrolyzale N, rapidly available P and rapidly available K by 1.44%-6.10%, 0.01-0.12 g/kg, 1.89%- 11.32%, 0.12%-3.56%, 1.06%-11.76%, 0.04%-18.93% and 0.98%-23.12%, respec- tively, and the effect of the monoculture of common vetch was the best.(3) The overall change of soil pH was not obvious.(4)Green manure turnover can increase the yield and output of flue-cured tobacco, and the effect of the monoculture of common vetch was the best. [Conclusion] The monoculture of common vetch can be generalized in the dry land of Xiangxi tobacco-planting areas. 展开更多
关键词 Green manure Mixed cropping Soil physical and chemical properties Economic characters of flue-cured tobacco
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Separator coatings as efficient physical and chemical hosts of polysulfides for high-sulfur-loaded rechargeable lithium–sulfur batteries 被引量:4
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作者 Masud Rana Ming Li +4 位作者 Qiu He Bin Luo Lianzhou Wang Ian Gentle Ruth Knibbe 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2020年第5期51-60,共10页
Lithium-sulfur batteries(LSBs)are promising alternative energy storage devices to the commercial lithium-ion batteries.However,the LSBs have several limitations including the low electronic conductivity of sulfur(5... Lithium-sulfur batteries(LSBs)are promising alternative energy storage devices to the commercial lithium-ion batteries.However,the LSBs have several limitations including the low electronic conductivity of sulfur(5×10^-30S cm^-1),associated lithium polysulfides(PSs),and their migration from the cathode to the anode.In this study,a separator coated with a Ketjen black(KB)/Nafion composite was used in an LSB with a sulfur loading up to 7.88 mg cm^-2to mitigate the PS migration.A minimum specific capacity(Cs)loss of 0.06%was obtained at 0.2 C-rate at a high sulfur loading of 4.39 mg cm^-2.Furthermore,an initial areal capacity up to 6.70 mAh cm^-2 was obtained at a sulfur loading of 7.88 mg cm^-2.The low Cs loss and high areal capacity associated with the high sulfur loading are attributed to the large surface area of the KB and sulfonate group(SO3^-)of Nafion,respectively,which could physically and chemically trap the PSs. 展开更多
关键词 Lithium-sulfur battery SEPARATOR coating physical and chemical confinement Self-discharge HIGH SULFUR loading Specific capacity loss HIGH areal capacity
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Overview of Physical and Chemical, Operational Properties of Nitrous Oxide Used as a Propellant for Low-thrust Rocket Engines 被引量:2
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作者 A.A.Boryaev 《火炸药学报》 EI CAS CSCD 北大核心 2019年第1期17-31,I0001,共16页
The results of a system analysis of the efficiency of nitrous oxide(N_2O) as a propellant component for small space vehicles(SSV) were presented. A criterion for mass efficiency of the SSV propulsion system(PS) is det... The results of a system analysis of the efficiency of nitrous oxide(N_2O) as a propellant component for small space vehicles(SSV) were presented. A criterion for mass efficiency of the SSV propulsion system(PS) is determined. The current global state-of-the-art of SSV PSs is shown. The application field of nitrous oxide in SSV PSs is calculated and mass efficiency of N_2O application is quantitatively determined. An overview of physical and chemical as well as operational properties of nitrous oxide as a promising, non-toxic component of rocket propellant is provided. Main physical and chemical constants of gaseous and liquid nitrous oxide; chemical properties of N_2O, thermal stability of N_2O, catalytic decomposition of N_2O, a mechanism of decomposition of N_2O, catalysts for decomposition of N_2O, ballast additives to N_2O, application of nitrous oxide, nitrous oxide as a rocket propellant, production of nitrous oxide, toxicity of nitrous oxide, fire hazard of N_2O, requirements to equipment when handling N_2O; storage and transportation of N_2O are considered. It is demonstrated that nitrous oxide is a chemical compound meeting the requirements to rocket propellants, including those related to the environmental friendliness of propellants. With 75 references. 展开更多
关键词 ROCKET PROPELLANT nitrous oxide physical and chemical properties
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Improvements of marine clay slurries using chemicale-physical combined method(CPCM) 被引量:1
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作者 Dongqing Wu Wenyu Xu Romy Tjuar 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2015年第2期220-225,共6页
In this paper, the effectiveness, applicability and validity of chemicalephysical combined methods(CPCMs) for treatment of marine clay (MC) slurries were evaluated. The method CPCM1 combineschemical stabilization ... In this paper, the effectiveness, applicability and validity of chemicalephysical combined methods(CPCMs) for treatment of marine clay (MC) slurries were evaluated. The method CPCM1 combineschemical stabilization and vacuum preloading (VP), while CPCM2 is similar to CPCM1 but includes boththe application of surcharge and use of geo-bags to provide confinement during surcharge preloading.The key advantage of CPCM2 using geo-bags is that the surcharge can be immediately applied on thechemically stabilized slurries. Two types of geo-bags were investigated under simulated land filling anddyke conditions, respectively. The test results show that the shear strength (cu) of treated slurry byCPCM2 is generally much higher than that by CPCM1. Besides, the use of CPCM2 can significantly reducethe treatment time due to the short drainage paths created by geo-bags. Overall, CPCM2 allows fasterconsolidation and higher preloading that help to achieve higher mechanical properties of the stabilizedslurry. There are consistent relationships between cU and water content of slurries treated by CPCM2.Several important observations were also made based on comparisons of experimental data. 2015 Institute of Rock and Soil Mechanics, Chinese Academy of Sciences. Production and hosting byElsevier B.V. All rights reserved. 展开更多
关键词 chemical e physical combined method(CPCM) Soil improvement Marine clay(MC) slurry Land reclamation chemical stabilization Vacuum preloading(VP) Geo-bags SURCHARGE
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Revisiting the Role of Physical Confinement and Chemical Regulation of 3D Hosts for Dendrite-Free Li Metal Anode 被引量:3
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作者 Shufen Ye Xingjia Chen +8 位作者 Rui Zhang Yu Jiang Fanyang Huang Huijuan Huang Yu Yao Shuhong Jiao Xiang Chen Qiang Zhang Yan Yu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2022年第11期290-306,共17页
Lithium metal anode has been demonstrated as the most promising anode for lithium batteries because of its high theoretical capacity,but infinite volume change and dendritic growth during Li electrodeposition have pre... Lithium metal anode has been demonstrated as the most promising anode for lithium batteries because of its high theoretical capacity,but infinite volume change and dendritic growth during Li electrodeposition have prevented its practical applications.Both physical morphology confinement and chemical adsorption/diffusion regulation are two crucial approaches to designing lithiophilic materials to alleviate dendrite of Li metal anode.However,their roles in suppressing dendrite growth for long-life Li anode are not fully understood yet.Herein,three different Ni-based nanosheet arrays(NiO-NS,Ni_(3)N-NS,and Ni_(5)P_(4)-NS)on carbon cloth as proof-of-concept lithiophilic frame-works are proposed for Li metal anodes.The two-dimensional nanoarray is more promising to facilitate uniform Li^(+)flow and electric field.Compared with the NiO-NS and the Ni_(5)P_(4)-NS,the Ni_(3)N-NS on carbon cloth after reacting with molten Li(Li-Ni/Li_(3)N-NS@CC)can afford the strongest adsorption to Li+and the most rapid Li+diffusion path.Therefore,the Li-Ni/Li_(3)N-NS@CC electrode realizes the lowest overpotential and the most excellent electrochemical performance(60 mA cm^(−2)and 60 mAh cm^(−2)for 1000 h).Furthermore,a remarkable full battery(LiFePO_(4)||Li-Ni/Li_(3)N-NS@CC)reaches 300 cycles at 2C.This research provides valuable insight into designing dendrite-free alkali metal batteries. 展开更多
关键词 Li metal anodes 3D carbon framework Ni-based nanosheets physical morphology confinement chemical adsorption/diffusion regulation
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Responses of microbial activities and soil physical-chemical properties to the successional process of biological soil crusts in the Gurbantunggut Desert,Xinjiang 被引量:29
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作者 BingChang ZHANG XiaoBing ZHOU YuanMing ZHANG 《Journal of Arid Land》 SCIE CSCD 2015年第1期101-109,共9页
Biological soil crusts (BSCs) are capable of modifying nutrient availability to favor the establishment of biogeochemical cycles. Microbial activities serve as critical roles for both carbon and nutrient transformat... Biological soil crusts (BSCs) are capable of modifying nutrient availability to favor the establishment of biogeochemical cycles. Microbial activities serve as critical roles for both carbon and nutrient transformation in BSCs. However, little is known about microbial activities and physical-chemical properties of BSCs in the Gurbantunggut Desert, Xinjiang, China. In the present research, a sampling line with 1-m wide and 20-m long was set up in each of five typical interdune areas selected randomly in the Gurbantunggut Desert. Within each sampling line, samples of bare sand sheet, algal crusts, lichen crusts and moss crusts were randomly collected at the depth of 0-2 cm. Varia- tions of microalgal biomass, microbial biomass, enzyme activities and soil physical-chemical properties in different succession of BSCs were analyzed. The relationships between microalgal biomass, microbial biomass, enzymatic activities and soil physical-chemical properties were explored by stepwise regression. Our results indicate that micro- algal biomass, microbial biomass and most of enzyme activities increased as the BSCs developed and their highest values occurred in lichen or moss crusts. Except for total K, the contents of most soil nutrients (organic C, total N, total P, available N, available P and available K) were the lowest in the bare sand sheet and significantly increased with the BSCs development, reaching their highest values in moss crusts. However, pH values significantly decreased as the BSCs developed. Significant and positive correlations were observed between chlorophyll a and microbial biomass C. Total P and N were positively associated with chlorophyll a and microbial biomass C, whereas there was a significant and negative correlation between microbial biomass and available P. The growth of cyanobacteria and microorganism contributed C and N in the soil, which offered substrates for enzyme activities thus increasing enzyme activities. Probably, improvement in enzyme activities increased soil fertility and promoted the growth of cyanobacteria, eukary- otic algae and heterotrophic microorganism, with the accelerating succession of BSCs. The present research found that microalgal-microbial biomass and enzyme activities played important roles on the contents of nutrients in the successional stages of BSCs and helped us to understand developmental mechanism in the succession of BSCs. 展开更多
关键词 chlorophyll a microbial biomass C soil enzyme physical-chemical properties biological soil crusts
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Contribution to Comparative Study of Physical-Chemical Characteristics of Diack Basalt and Bandia Limestone for Use in Railway Engineering 被引量:3
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作者 Abdoulaye Diedhiou Libasse Sow Adama Dione 《Geomaterials》 2020年第2期25-34,共10页
This paper presents a comparative study of Physical-Chemical characteristics of Limestone and Basalt (from Senegalese quarries). First, chemical tests show that Basalt is richer in silica 51.59% versus 2.84% for Limes... This paper presents a comparative study of Physical-Chemical characteristics of Limestone and Basalt (from Senegalese quarries). First, chemical tests show that Basalt is richer in silica 51.59% versus 2.84% for Limestone. Basalt is made up of silica minerals and essentially carbonated minerals with a CaO percentage of 50.05%. Chemical results also show that Basalt is richer in iron 12.71% versus 0.44% for Limestone. Finally, they revealed a fire loss of 40.91% for Limestone and 2.44% for Basalt. Second, physical analysis results show that Diack Basalt has the best characteristics with a flattening coefficient of 5% between 5% and 20%;the percentage of pollutants is 0.36% less than 1%;the Los Angeles coefficient is 12.21% below 15, while Bandia Limestone gives a flattening coefficient of 3%;the Los Angeles coefficient of 40.17% and the percentage of pollutant (2.4%) well above 2%. It is noted that the percentage of Limestone pollutant is too high. These important results show the net advantage of Basalt compared to Limestone in terms of physical-chemical characteristics. 展开更多
关键词 BALLAST Railways BASALT LIMESTONE physical-chemical CHARACTERISTIC
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Selected physical and chemical properties of mechanically extracted neem seed oil sourced as a preservative for ligno-cellulose in south-western Nigeria
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作者 Andrew A. ERAKHRUMEN 《Forestry Studies in China》 CAS 2011年第4期263-269,共7页
Most of the seeds produced by neem (Azadirachta indica A. Juss) trees in Nigeria are currently underutilized. Hence, relevant literature provides only limited information conceming many of the seed oils from this co... Most of the seeds produced by neem (Azadirachta indica A. Juss) trees in Nigeria are currently underutilized. Hence, relevant literature provides only limited information conceming many of the seed oils from this country, especially where it concems the potential applications of these oils as preservatives for ligno-cellulose against bio-deterioration. Using standard procedures therefore, this study was carried out to evaluate and document selected physical and chemical properties of neem seed oil (NSO), mechanically extracted using a cold press at 31.03 N-mm^-2 pressure and a room temperature of 25 ± 2℃. The results show that oil yield was 38.42% with a specific gravity of 0.91 ± 0.01. The amount of acid was 18.24 ± 1.31 mg KOH.g^-1 and that of iodine 93.12 ± 2.01 g-100 g^- 1, while saponification and peroxide values were 172.88 ± 2.06 and 1.42 ± 0.04 mg·g^-1 respectively. The implication of the values obtained, particularly those for the chemical properties, as they concern the potential application of NSO as a preservative for ligno-eellulose, is likely that it may be useful in this regard since the values may support some of the documented anti-microbial properties of the oil, although other physical and chemical properties that may affect this potential are recommended for investigations. Conclusions and other recommendations follow in line with the results of the study. 展开更多
关键词 neem seed oil physical and chemical properties mechanical extraction cold press
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Studies on Dynamic of Physical and Chemical Characteristics of Water in GaoBaZhou Reservoir after Filter-feeding Fish's Multiplication and Stocking
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作者 CAI Yu LIU Zhi-guo +5 位作者 CAI Yan-zhi WAN Song-tong XIA Jian-jun LI Xian-cai LEI Xiao-zhong WANG Liang 《Animal Husbandry and Feed Science》 CAS 2012年第5期231-235,共5页
[ Objective] The aim was to provide scientific basis for purifying water quality, ecological restoration and fishery breeding of GaoBaZhou reservoir multiplication and stocking. [ Method] Monitoring of normal water ph... [ Objective] The aim was to provide scientific basis for purifying water quality, ecological restoration and fishery breeding of GaoBaZhou reservoir multiplication and stocking. [ Method] Monitoring of normal water physical, chemical characteristics and different number of data of GaoBaZhou reservoir was conducted in 2010 and 2011 after different amount of filter-feeding fishes stocking in this reservoir. [ Result] The water physical and chemical factors TN, NO2, NO3-N-N, TP and COD, Chl. a in 2011 were significantly less than 2010, 2011 month average 1.389 mg/L, 0.039 6 rng/L, 1.211 7 mg/L, 0.137 3 mg/L, 16.191 mg/L, 10.226 8 mg/m3, 2010 month average 1.659 mg/L, 0.066 2 mg/L, 1.472 9 mg/L, 0.099 9 rag/L, 18.314 8 mg/L, 14.917 8 mg/L. The calculation results of TSIM showed that 2011 reservoir eutrophication TSIM were less than 2010, up to 53.78 and 57.36. E Coaclusion: The whole reservoir area revealed mild eutrophication (the TSIM 〉 53), and it suggested that the filterfeeding fishes amount could be increased in the reservoir. 展开更多
关键词 GaoBaZhou reservoir Multiplication and stocking physical and chemical characteristics Purification effect
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Effects of Long-term Site-specific Fertilization on Soil Physical and Chemical Properties and Nutrients in Dry Farmland
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作者 Xiaojun WANG Yuqing SUN +6 位作者 Yong WANG Xiaojuan ZHANG Shangpei ZHANG Junxue YANG Shiwu LUO Jihong SHANG Bingwen CHENG 《Agricultural Science & Technology》 CAS 2017年第11期2118-2122,共5页
In order to investigate the variation in soil physical and chemical properties and nutrients in the mountainous areas in southern Ningxia, and to provide a theoretical basis for fertilization management in local farml... In order to investigate the variation in soil physical and chemical properties and nutrients in the mountainous areas in southern Ningxia, and to provide a theoretical basis for fertilization management in local farmland, the soil p H, total salt content,crop root length, root weight, soil organic matter, available nitrogen, total nitrogen, total phosphorous and total potassium in different fertilization treatments were measured from 2010 to 2016. Multiple comparisons of the data were performed using Duncan's new multiple range test. The results indicated that in the 0-20 cm soil layer, soil p H value and total salt content changed in different patterns, and varied greatly from 2010 to 2016(P<0.05). The changes of both root length and root weight of millet over time fitted S-shaped curves. The root length and root weight in the four fertilization treatments(Treatment 2 to Treatment5) increased faster than those in the control(Treatment 1). The soil organic matter content in all the five treatments gradually increased from 2010 to 2016. The content of alkaline hydrolyzable nitrogen in soil rapidly increased in the first two to three years of the experiment, followed by a slow increase or decrease in 2013, and then raised rapidly again from 2014 to 2016.The soil total nitrogen content varied significantly from 2010 to 2016. The total phosphorus content in soil changed in a different pattern from that of total nitrogen content. The seven-year field trails revealed that soil p H, total salt content, root length, root weight and soil nutrient all changed with the increase of fertilizer level, and that long-term fertilization is of significance for maintaining soil fertility, improving soil quality and reducing soil salinization. 展开更多
关键词 Site-specific fertilization physical and chemical properties NUTRIENT Soil quality
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Correlation Analysis of Processing Technology,Physical Parameters and Chemical Components during Plain Stir-baking of Trichosanthis Radix
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作者 Xinhong ZHAO Ruiying LI +3 位作者 Chao SUN Zhenhua LIU Xu XIAO Tianchao CHEN 《Medicinal Plant》 CAS 2021年第5期51-55,59,共6页
[Objectives]To explore the correlation of processing technology,physical parameters and chemical components during plain stir-baking of Trichosanthis Radix.[Methods]Based on mixture uniform experiment design,the Trich... [Objectives]To explore the correlation of processing technology,physical parameters and chemical components during plain stir-baking of Trichosanthis Radix.[Methods]Based on mixture uniform experiment design,the Trichosanthis Radix was prepared by plain stir-bake method.Delphi method was used to evaluate and select the highest-scoring processed product for measuring physical parameters.UV spectrophotometry was used to determine the contents of starch and polysaccharide.The correlation and linear regression model of processing technology,physical parameters and chemical components were established with the aid of SPSS 26.0[Results]After processing by plain stir-bake method,the relative density and chromaticity showed a decreasing trend in the processed products of Trichosanthis Radix,the oxidation value,hydroscopic rate and swelling decreased firstly and then increased,and pH increased firstly and then decreased.The content of total starch decreased,the content of polysaccharide increased,and there was a negative correlation between them.There was a significant positive correlation between temperature and oxidation value,swelling and hydroscopic rate,hydroscopic rate and polysaccharide,and there was a significant negative correlation between relative density and hydroscopic rate or polysaccharide,total starch and hydroscopic rate or swelling.The linear relation model between processing technology and physical parameters and chemical components was r2>0.9.[Conclusions]After processing by plain stir-bake method,the physical parameters of Trichosanthis Radix changed,and there may be mutual conversion between total starch and polysaccharides.To a certain extent,physical parameters can be used to evaluate the quality of processed products of Trichosanthis Radix.This study is expected to provide a reference for research on quality evaluation of processed products of traditional Chinese medicine. 展开更多
关键词 Trichosanthis Radix Processing technology physical parameters chemical components CORRELATION
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GIS-Based Assessment of Soil Chemical and Physical Properties as a Basis for Land Reclamation in Toshka Area, Aswan, EGYPT
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作者 Ahmed A. M. Awad Mostafa M. A. Al-Soghir 《Open Journal of Geology》 2023年第7期697-719,共23页
The accurate assessment of soil properties is a crucial factor for composing and implementing reclamation plans. The main objective of this study was to evaluate soil chemical and physical properties and calculate the... The accurate assessment of soil properties is a crucial factor for composing and implementing reclamation plans. The main objective of this study was to evaluate soil chemical and physical properties and calculate the chemical and fertility index for assisting land reclamation in Toshka area. The Toshka area is located between latitudes 31°32'N and 31°36'N and longitudes 32°40'E and 32°60'E. GIS was used to select 16 sites. The results revealed the soil has undesirable characteristics. The soil pH ranged from slightly alkaline to moderately alkaline. Furthermore, it was characterized as saline (with a ECe of 4.65 - 11.45 dS⋅m<sup>−1</sup>) and moderately calcareous soil (with CaCO<sub>3</sub> at 11.85% - 17.20%). The soil had a low soil organic matter content which did not exceed 0.18%. The soil was dominated by a sandy loam texture (62.50%) followed by a sandy clay loam texture (18.75%). The bulk density, total soil porosity and saturated hydraulic conductivity values varied with 1.38 - 1.55 Mg⋅cm<sup>−3</sup>, 41.85% - 48.45% and 1.20 - 3.34 cm⋅h<sup>−1</sup>, respectively. The chemical index ranged from low to moderate quality. The correlations between the parameters osculated between negative and positive. Therefore, the soil may be reclaimed if the soil properties are improved and crop selection is optimized for this soil. 展开更多
关键词 Land Reclamation Soil chemical and physical Properties chemical Quality Index Fertility Quality Index
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Changing Rules of Physical and Chemical Properties of Eucalyptus uraphylla spp. Forest at Different Ages in Southwest Yunnan Province 被引量:5
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作者 赵筱青 丁宁 闫平 《Agricultural Science & Technology》 CAS 2012年第6期1298-1302,共5页
[Objective] The aim was to study on changing rules of physical and chemical properties of Eucalyptus uraphylla spp. forest at different ages in Southwest of Yunnan Province. [Method] In the research, field survey and ... [Objective] The aim was to study on changing rules of physical and chemical properties of Eucalyptus uraphylla spp. forest at different ages in Southwest of Yunnan Province. [Method] In the research, field survey and laboratory analysis were adopted to study on physical and chemical properties of soils for the Eucalyptus uraphylla spp. at the first cutting ages in Lancang County. [Result] With the increasing of forest ages, for physical properties of soils, soil bulk density was increasing, and soil structure became poor; water contents in soils and capillary porosity were improving, but total soil porosity and non-capillary porosity were decreasing. For chemical properties, pH of soil dropped, but soil acidity improved; organic matter, total N, hydrolysable nitrogen, available phosphorus, and available potassium all declined; exchangeable Ca and Mg were improving due to fertilization and Ca and Mg lower consumption. The results showed that plays important roles in water absorption of soils and vegetation growth were improved with age increase by Eucalyptus uraphylla spp. forest, but ventilation and fertility declined accordingly. [Conclusion] The research indicated that dry branches and fallen leaves should be preserved and nutrient cycling should be protected during introduction and management of Eucalyptus uraphylla spp. to guarantee the nutrients in dry branches and leaves are back to soils, providing theoretical references for management of forest plantation and environment protection. 展开更多
关键词 Eucalyptus uraphylla spp. physical and chemical properties Soil fertility Lancang County
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Study on the Physical and Chemical Conditionsof Ore Formation of Hetai Ductile Shear Zone-Hosted Gold Deposit and Discovery of Melt Inclusions 被引量:1
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作者 李兆麟 翟伟 +2 位作者 李文 石贵勇 文拥军 《Chinese Journal Of Geochemistry》 EI CAS 2002年第1期40-51,共12页
The Hetai ductile shear zone-hosted gold deposit occurs in the deep-seated fault mylonite zone of the Sinian-Silurian metamorphic rock series. In this study there have been discovered melt inclusions, fluid-melt inclu... The Hetai ductile shear zone-hosted gold deposit occurs in the deep-seated fault mylonite zone of the Sinian-Silurian metamorphic rock series. In this study there have been discovered melt inclusions, fluid-melt inclusions and organic inclusions in ore-bearing quartz veins of the ore deposit and mylonite for the first time. The homogenization temperatures of the various types of inclusions are 160℃, 180-350℃, 530℃ and 870℃ for organic inclusions, liquid inclusions, two-phase immiscible liquid inclusions and melt inclusions, respectively. Ore fluid is categorized as the neutral to basic K\++-Ca\+\{2+\}-Mg\+\{2+\}-Na\++-SO\+\{2-\}\-4-HCO\+-\-3-Cl\+- system. The contents of trace gases follow a descending order of H\-2O>CO\-2>CH\-4> (or <) H\-2>CO>C\-2H\-2>C\-2H\-6>O\-2>N\-2. The concentrations of K\++, Ca\+\{2+\}, SO\+\{2-\}\-4, HCO\+-\-3, Cl\+-, H\-2O and C\-2H\-2 in fluid inclusions are related to the contents of gold and the Au/Ag ratios in ores from different levels of the gold deposit.This is significant for deep ore prospecting in the region. Daughter minerals in melt inclusions were analyzed using SEM. Quartz, orthoclase, wollastonite and other silicate minerals were identified. They were formed in different mineral assemblages. This analysis further proves the existence of melt inclusions in ore veins. Sedimentary metamorphic rocks could form silicate melts during metamorphic anatexis and dynamic metamorphism, which possess melt-solution characteristics. Ore formation is related to the multi-stage forming process of silicate melt and fluid. 展开更多
关键词 热液交互作用 金矿床 物理化学条件 成矿带 成矿作用
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Effect of Different Cultivation Practices on Soil Physical and Chemical Properties for Greenhouse Vegetables under Long-Term Continuous Cropping 被引量:2
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作者 Lijuan GAO Guoyuan ZOU +3 位作者 Lianfeng DU Shunjiang LI Jing LIU Hongkai DUAN 《Asian Agricultural Research》 2018年第9期74-81,共8页
Five kinds of greenhouse vegetables( eggplant,loofah,tomato,cucumber and pepper) were selected in summer uprooting stage from greenhouse in Shouguang area,Shandong Province. Total nitrogen,ammonium nitrogen,nitrate ni... Five kinds of greenhouse vegetables( eggplant,loofah,tomato,cucumber and pepper) were selected in summer uprooting stage from greenhouse in Shouguang area,Shandong Province. Total nitrogen,ammonium nitrogen,nitrate nitrogen,available phosphorus,available potassium,organic matter content and p H,EC value of three soil layers were measured,respectively. The results showed that the total nitrogen,ammonium nitrogen,nitrate nitrogen,available phosphorus and available potassium in the soil were mainly accumulated in the upper soil,which made the soil acidification trend,because different farmers adopted different cultivation practices for different greenhouse vegetables in Shouguang region,but there was no significant effect on soil EC value. The input of ammonium nitrogen and nitrate nitrogen and other related fertilizers to greenhouse cucumber was higher than that of other greenhouse vegetables,but the amount of available potassium fertilizer and organic matter input to greenhouse tomato under different cultivation practices was lower than other greenhouse vegetables. In Shouguang area,the input of organic matter into greenhouse vegetables should be increased by increasing the proportion of manure input to increase the content of soil organic carbon,so as to achieve the balance of carbon and nitrogen ratio,and to provide a scientific basis for the establishment of an evaluation system for the environmental benefits brought about by chemical fertilizer reduction in greenhouse vegetables in Shouguang area. 展开更多
关键词 茄子 有机肥 肥料 种植业
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