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Effect of Reducing Application of Chemical Fertilizers and Chemical Pesticides on Physiological Traits,Yield and Quality of Radish
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作者 Weiling YUAN Shangyong YUAN +5 位作者 Caixia GAN Lei CUI Zhongjiu JIAO Yong MIN Fengjuan ZHU Zhengming QIU 《Asian Agricultural Research》 2016年第10期88-89,100,共3页
This paper studied the effect of reducing application of chemical fertilizer,increasing application of functional organic fertilizer and trace elements and fully using biological pesticides on physiological traits,yie... This paper studied the effect of reducing application of chemical fertilizer,increasing application of functional organic fertilizer and trace elements and fully using biological pesticides on physiological traits,yield and quality of radish. The results showed that applying functional organic fertilizer and trace elements and fully using biological pesticides could help to significantly improve the radish fleshy root yield,increase soluble sugar and vitamin C content,reduce crude fiber and nitrate content,but had no significant influence on radish moisture content,glucosinolates and chlorpyrifos content in organophosphorus pesticides. 展开更多
关键词 Reducing application of chemical fertilizer Reducing application of chemical pesticides RADISH Yield and Quality
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Progress of the discovery, application, and control technologies of chemical pesticides in China 被引量:17
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作者 PAN Xing-lu DONG Feng-shou +3 位作者 WU Xiao-hu XU Jun LIU Xin-gang ZHENG Yong-quan 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2019年第4期840-853,共14页
Pesticides, which have the dual characteristics of being both helpful and harmful, are important materials for ensuring food security and human health. Therefore, the rational development, scientific application, and ... Pesticides, which have the dual characteristics of being both helpful and harmful, are important materials for ensuring food security and human health. Therefore, the rational development, scientific application, and effective control of pesticides are very important. In this paper, from the perspectives of pesticide discovery, formulation processing, application mode, residue monitoring, and pollution elimination and prediction, trends in the research progress and development of pesticides in China were systematically summarized to provide an important reference for the development of pesticides with high efficiency and low risk and for the reduction of pesticide application. 展开更多
关键词 PESTICIDE DISCOVERY FORMULATION processing APPLICATION RESIDUE monitoring pollution ELIMINATION and prediction
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Advances in Measures of Reducing Chemical Pesticides to Control Plant Diseases
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作者 Yanmin Sun Jinfeng Han +1 位作者 Xiaoli Chen Hui Guo 《Plant Diseases and Pests》 CAS 2021年第5期1-6,16,共7页
In order to provide the technological support for further implementing measures of reducing chemical pesticide to control plant diseases,the research progress on non-chemical pesticide measures to control plant diseas... In order to provide the technological support for further implementing measures of reducing chemical pesticide to control plant diseases,the research progress on non-chemical pesticide measures to control plant diseases are reviewed from the aspects of agricultural control,botanical pesticide control and microbial pesticide control,and the development prospects are proposed,including accelerating innovative research on botani-cal pesticide control such as Chinese herb extracts,and screening microbial pesticides from valuable bio-control bacteria or plant endophyte metabolites for commercial production and utilization. 展开更多
关键词 Reduction of chemical pesticide Agricultural control Botanical pesticide Microbial pesticide Plant disease Disease control
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Field Efficacy of Chemical Pesticides against Maruca vitrata Fabricius(Lepidoptera:Crambidae)Infesting Soybean in Brazil
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作者 José Fernando Jurca Grigolli André Luis Faleiros Lourencao Crébio José Avila 《American Journal of Plant Sciences》 2015年第4期537-544,共8页
The soybean pod borer, Maruca vitrata, can cause great damage by attacking pods from soybean plants. The aim of this study was to evaluate the field efficacy of chemical pesticides, when applied in spray, against soyb... The soybean pod borer, Maruca vitrata, can cause great damage by attacking pods from soybean plants. The aim of this study was to evaluate the field efficacy of chemical pesticides, when applied in spray, against soybean pod borer. The experiment was conducted in the experimental area of Funda&ccedil&atildeo, MS, in Maracaju, MS, Brazil, in the growing season 2012/2013. The randomized block design was used with six treatments (teflubenzuron, flubendiamide, methomyl, chlorantraniliprole + lambda-cyhalothrin, chlorpyrifos, and a control treatment without insecticide) and five replications, on cultivar BMX Turbo RR. Evaluations were performed at one, four, seven, 10, and 14 days after pesticides application (DAA), and were based on the percentage of attacked plants with M. vitrata presence, and the number of alive larvae per plant. On each evaluation, 10 plants per plot were analyzed. The data were subjected to ANOVA and the treatment means were compared by Tukey test at 5% probability. Pesticides teflubenzuron, flubendiamide, chlorantraniliprole + lambda-cyhalothrin, and chlorpyrifos significantly reduced the percentage of attacked plants by M. vitrata. Chlorpyrifos, teflubenzuron, and chlorantraniliprole + lambda-cyhalothrin showed higher field efficacy to control M. vitrata from the first day after application. However, flubendiamide showed good efficacy from 10 days after application, and joined the group with higher efficacy (chlorpyrifos, teflubenzuron, and chlorantraniliprole + lambda-cyhalothrin). Methomyl showed no field efficacy against legume pod borer. 展开更多
关键词 Legume Pod Borer Glycine max chemical Control
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Evaluation of Agricultural Contamination Level by Heavy Metals and Pesticides in Sediments of Rivers and Water Bodies for Shrimp Fishing in the Lower Ouémé: Case of the Aguigadji, Ahlan and Sele Stations in Benin
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作者 Souradjou Orou Goura Fadéby Modeste Gouissi +3 位作者 Armelle Sabine Yélignan Hounkpatin Wakili Bolatito Yessoufou Tayéwo Sylvain Biaou Nonvignon Martial Fassinou 《Advances in Materials Physics and Chemistry》 CAS 2024年第2期25-46,共22页
This study assessed sediment contamination by heavy metals and pesticide active ingredients linked to chemical inputs used in agricultural activities in the lower Ouémé. Pesticide residues from the organochl... This study assessed sediment contamination by heavy metals and pesticide active ingredients linked to chemical inputs used in agricultural activities in the lower Ouémé. Pesticide residues from the organochlorine, pyrethroid and organophosphorus families were investigated by gas chromatography, and heavy metals (Cd, Pb, As, Ni, Zn, Fe, Mg, Cr and Hg) by atomic absorption spectrophotometry. The metallic pollution indices, the contamination factor (CF) and the ecological risk index were calculated. The results revealed 8 active ingredients in the rainy season and 9 in the dry season. Glyphosate was the active ingredient with the highest concentration at all stations, 9.65 ± 0.84 mg/kg recorded in the dry season at the Aguigadji station. All glyphosate values were above the EQS. DDT, Atrazine and Endosulfan also showed high concentrations in the dry and rainy seasons. Emamectin, Abamectin and Lambda Cyhalothrin also showed high concentrations in the dry season at Aguigadji, Ahlan and Sele. Only glyphosate was recorded at the control station (Toho), but in very low concentrations. Lead showed the highest concentrations at all the stations, 265.96 ± 21.02 mg/Kg in the rainy season and 255.38 ± 79.09 mg/Kg in the dry season, all detected at the Aguigadji station and above the EQS. Zn, Ni, Fe, Cu and Cr were all representative in both the dry and rainy seasons at the contaminated stations. Manganese showed high concentrations in the rainy season. Pb showed very high contamination (FC ≥ 6) at the Aguigadji and Ahlan stations and significant contamination (3 ≤ FC 6) at the Sele station in both the rainy and dry seasons. Ni, Hg and Cd, showed either moderate or significant contamination at the contaminated stations. The risk values showed a considerable ecological Ri (190 ≤ Ri < 380) in the rainy season and a moderate ecological Ri (95 ≤ Ri < 190) in the dry season at these contaminated stations. 展开更多
关键词 pesticides Heavy Metals SEDIMENTS Shrimp Fishing Area Lower Ouémé
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Extraction,chemical components,bioactive functions and adulteration identification of walnut oils:A review
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作者 Yuan Gao Jia Hu +6 位作者 Xia Su Qi Li Caihong Su Yongling Li Gaiqin Ma Siyu Zhang Xiuzhu Yu 《Grain & Oil Science and Technology》 CAS 2024年第1期30-41,共12页
Walnut oil is a functional wood oil known to researchers that may potentially be a large source of Chinese edible oils.There are various extraction methods for walnut oil,including traditional(pressing,solvent-and enz... Walnut oil is a functional wood oil known to researchers that may potentially be a large source of Chinese edible oils.There are various extraction methods for walnut oil,including traditional(pressing,solvent-and enzymeassisted extraction)and novel methods(microwave,ultrasound,supercritical CO_(2),subcritical and other extraction technologies).Walnut oil is rich in nutrients,including phytosterols,tocopherols,polyphenols,squalene and minerals.It provides many health benefits,such as antioxidant,antitumor,anti-inflammatory,antidiabetic and lipid metabolism-related functions.In addition,the authentication of walnut oil has received much research attention.The present review provides detailed research on walnut oil extraction,composition,health benefits and adulteration identification methods.The path toward further walnut oil improvement in the context of the market value of walnut oil is also discussed. 展开更多
关键词 Extraction technology chemical composition Bioactive AUTHENTICATION
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The chemical environment and structural ordering in liquid Mg-Y-Zn system:An ab-initio molecular dynamics investigation of melt for the formation mechanism of LPSO structure
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作者 Tangpeng Ma Jin Wang +5 位作者 Kaiming Cheng Chengwei Zhan Jixue Zhou Jingyu Qin Guochen Zhao Xinfang Zhang 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第2期815-824,共10页
In an effort to clarify the formation mechanism of LPSO structure in Mg-Y-Zn alloy,the chemical environment and structural ordering in liquid Mg-rich Mg-Y-Zn system are investigated with the aid of ab-initio molecular... In an effort to clarify the formation mechanism of LPSO structure in Mg-Y-Zn alloy,the chemical environment and structural ordering in liquid Mg-rich Mg-Y-Zn system are investigated with the aid of ab-initio molecular dynamics simulation.In liquid Mg-rich Mg-Y alloys,the strong Mg-Y interaction is determined,which promotes the formation of fivefold symmetric local structure.For Mg-Zn alloys,the weak Mg-Zn interaction results in the fivefold symmetry weakening in the liquid structure.Due to the coexistence of Y and Zn,the strong attractive interaction is introduced in liquid Mg-Y-Zn ternary alloy,and contributes to the clustering of Mg,Y,Zn launched from Zn.What is more,the distribution of local structures becomes closer to that in pure Mg compared with that in binary Mg-Y and Mg-Zn alloys.These results should relate to the origins of the Y/Zn segregation zone and close-packed stacking mode in LPSO structure,which provides a new insight into the formation mechanism of LPSO structure at atomic level. 展开更多
关键词 Mg-Y-Zn chemical environment Structural ordering ab-initio molecular dynamics
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Resistance Monitoring of Field Populations of Panonychus citri to Three Pesticides
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作者 Yang HAN Tingmi YANG 《Plant Diseases and Pests》 2024年第2期4-8,共5页
[Objectives]The paper was to investigate the development of Panonychus citri resistance to commonly used pesticides in major citrus producing areas in China,and to screen out new green and efficient agents for its con... [Objectives]The paper was to investigate the development of Panonychus citri resistance to commonly used pesticides in major citrus producing areas in China,and to screen out new green and efficient agents for its control and prevention.[Methods]The resistance changes of field populations of P.citri to abamectin,pyridaben,and bifenazate in 12 locations across five provinces in China were compared using the leaf disc impregnation method.[Results]P.citri in the tested areas exhibited the most severe resistance to abamectin,with approximately 91.7%of the field populations showing high levels of resistance to abamectin(112.1-560.5 times);50%of P.citri populations exhibited high levels of resistance to pyridaben(123.0-202.7 times),while the remaining populations showed intermediate levels of resistance(25.6-80.3 times);except for the Zhejiang Xiangshan 2019 and Jiangxi Yudu 2019 populations,which exhibited a medium level of resistance to bifenazate,the remaining 10 monitored populations demonstrated a high level of resistance to bifenazate(140.4-686.1 times).[Conclusions]It is advisable to discontinue the use of abamectin and bifenazate due to significant resistance observed in populations of P.citri monitored in 12 locations across 5 provinces.It is recommended to reduce the frequency of pyridaben use and alternate with other acaricides that have different mechanisms of action due to the varying degrees of resistance developed. 展开更多
关键词 Panonychus citri RESISTANCE PESTICIDE Biological activity
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Expanding the Boundaries of the Chemical Space of DNA Methyltransferase 1 Modulators
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作者 Massyel S. Martínez-Cortés Diana L. Prado-Romero José L. Medina-Franco 《Computational Molecular Bioscience》 2024年第1期1-16,共16页
DNA methyltransferase 1 (DNMT1), one of the main epigenetic targets, is involved in the duplication of the DNA methylation pattern during replication, and it is essential for proper mammalian development. Small molecu... DNA methyltransferase 1 (DNMT1), one of the main epigenetic targets, is involved in the duplication of the DNA methylation pattern during replication, and it is essential for proper mammalian development. Small molecule DNMT1 modulators are attractive for biochemical epigenetic studies and have the potential to become drugs. So far, more than five hundred small molecules have been reported as DNMT1 inhibitors. However, only a limited number of DNMT1 activators have been disclosed because, at least in part, DNMT1 activators are typically regarded as negative data in virtual screening campaigns or optimization projects. This manuscript aims to report the chemical structures and biological activity of small molecules that increase the enzymatic activity of DNMT1. Results of the biochemical experimental assays are discussed. It was found that small molecule activators have a large variety of chemical scaffolds but share pharmacophore features. Visual analysis of the chemical space and multiverse based on molecular fingertips supported that activators are structurally diverse. This is the first report of eight small molecules that increase the enzymatic activity of DNMT1 by more than 400% in an enzymatic-based assay. The outcome warrants further investigation of the epigenetic activity of the compounds in a counter-screen assay, e.g., cell-based and in vivo context. 展开更多
关键词 chemical Multiverse CHEMOINFORMATICS EPIGENETICS Pharmacophore Hypothesis Small Molecules
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Jet formation and penetration performance of a double-layer charge liner with chemically-deposited tungsten as the inner liner
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作者 Bihui Hong Wenbin Li +2 位作者 Yiming Li Zhiwei Guo Binyou Yan 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第3期374-385,共12页
This paper proposes a type of double-layer charge liner fabricated using chemical vapor deposition(CVD)that has tungsten as its inner liner.The feasibility of this design was evaluated through penetration tests.Double... This paper proposes a type of double-layer charge liner fabricated using chemical vapor deposition(CVD)that has tungsten as its inner liner.The feasibility of this design was evaluated through penetration tests.Double-layer charge liners were fabricated by using CVD to deposit tungsten layers on the inner surfaces of pure T2 copper liners.The microstructures of the tungsten layers were analyzed using a scanning electron microscope(SEM).The feasibility analysis was carried out by pulsed X-rays,slug-retrieval test and static penetration tests.The shaped charge jet forming and penetration law of inner tungsten-coated double-layer liner were studied by numerical simulation method.The results showed that the double-layer liners could form well-shaped jets.The errors between the X-ray test results and the numerical results were within 11.07%.A slug-retrieval test was found that the retrieved slug was similar to a numerically simulated slug.Compared with the traditional pure copper shaped charge jet,the penetration depth of the double-layer shaped charge liner increased by 11.4% and>10.8% respectively.In summary,the test results are good,and the numerical simulation is in good agreement with the test,which verified the feasibility of using the CVD method to fabricate double-layer charge liners with a high-density and high-strength refractory metal as the inner liner. 展开更多
关键词 Shaped charge chemical vapor deposition TUNGSTEN Double-layer charge liner X-ray PENETRATION
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Effects of dietary Clostridium butyricum and rumen protected fat on meat quality,oxidative stability,and chemical composition of finishing goats
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作者 Meimei Zhang Zhiyue Zhang +9 位作者 Xinlong Zhang Changming Lu Wenzhu Yang Xiaolai Xie Hangshu Xin Xiaotan Lu Mingbo Ni Xinyue Yang Xiaoyang Lv Peixin Jiao 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第2期911-924,共14页
Background Clostridium butyricum(CB)is a probiotic that can regulate intestinal microbial composition and improve meat quality.Rumen protected fat(RPF)has been shown to increase the dietary energy density and provide ... Background Clostridium butyricum(CB)is a probiotic that can regulate intestinal microbial composition and improve meat quality.Rumen protected fat(RPF)has been shown to increase the dietary energy density and provide essential fatty acids.However,it is still unknown whether dietary supplementation with CB and RPF exerts beneficial effects on growth performance and nutritional value of goat meat.This study aimed to investigate the effects of dietary CB and RPF supplementation on growth performance,meat quality,oxidative stability,and meat nutritional value of finishing goats.Thirty-two goats(initial body weight,20.5±0.82 kg)were used in a completely randomized block design with a 2 RPF supplementation(0 vs.30 g/d)×2 CB supplementation(0 vs.1.0 g/d)factorial treatment arrangement.The experiment included a 14-d adaptation and 70-d data and sample collection period.The goats were fed a diet consisted of 400 g/kg peanut seedling and 600 g/kg corn-based concentrate(dry matter basis).Result Interaction between CB and RPF was rarely observed on the variables measured,except that shear force was reduced(P<0.05)by adding CB or RPF alone or their combination;the increased intramuscular fat(IMF)content with adding RPF was more pronounced(P<0.05)with CB than without CB addition.The pH24h(P=0.009),a*values(P=0.007),total antioxidant capacity(P=0.050),glutathione peroxidase activities(P=0.006),concentrations of 18:3(P<0.001),20:5(P=0.003)and total polyunsaturated fatty acids(P=0.048)were increased,whereas the L*values(P<0.001),shear force(P=0.050)and malondialdehyde content(P=0.044)were decreased by adding CB.Furthermore,CB supplementation increased essential amino acid(P=0.027),flavor amino acid(P=0.010)and total amino acid contents(P=0.024)as well as upregulated the expression of lipoprotein lipase(P=0.034)and peroxisome proliferator-activated receptorγ(PPARγ)(P=0.012),and downregulated the expression of stearoyl-CoA desaturase(SCD)(P=0.034).The RPF supplementation increased dry matter intake(P=0.005),averaged daily gain(trend,P=0.058),hot carcass weight(P=0.046),backfat thickness(P=0.006),concentrations of 16:0(P<0.001)and c9-18:1(P=0.002),and decreased the shear force(P<0.001),isoleucine(P=0.049)and lysine content(P=0.003)of meat.In addition,the expressions of acetyl-CoA carboxylase(P=0.003),fatty acid synthase(P=0.038),SCD(P<0.001)and PPARγ(P=0.022)were upregulated due to RPF supplementation,resulting in higher(P<0.001)content of IMF.Conclusions CB and RPF could be fed to goats for improving the growth performance,carcass traits and meat quality,and promote fat deposition by upregulating the expression of lipogenic genes of Longissimus thoracis muscle. 展开更多
关键词 chemical composition Clostridium butyricum Goats Meat quality Oxidative stability Rumen protected fat
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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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Shock-induced energy localization and reaction growth considering chemical-inclusions effects for crystalline explosives
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作者 Ruqin Liu Yanqing Wu +3 位作者 Xinjie Wang Fenglei Huang Xiaona Huang Yushi Wen 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第3期278-294,共17页
Chemical inclusions significantly alter shock responses of crystalline explosives in macroscale gap experiments but their microscale dynamics origin remains unclear.Herein shock-induced energy localization,overall phy... Chemical inclusions significantly alter shock responses of crystalline explosives in macroscale gap experiments but their microscale dynamics origin remains unclear.Herein shock-induced energy localization,overall physical responses,and reactions in a-1,3,5-trinitro-1,3,5-triazinane(a-RDX)crystal entrained various chemical inclusions were investigated by the multi-scale shock technique implemented in the reactive molecular dynamics method.Results indicated that energy localization and shock reaction were affected by the intrinsic factors within chemical inclusions,i.e.,phase states,chemical compositions,and concentrations.The atomic origin of chemical-inclusions effects on energy localization is dependent on the dynamics mechanism of interfacial molecules with free space volume,which includes homogeneous intermolecular compression,interfacial impact and shear,and void collapse and jet.As introducing various chemical inclusions,the initiation of those dynamics mechanisms triggers diverse decay rates of bulk RDX molecules and hereby impacts on growth speeds of final reactions.Adding chemical inclusions can reduce the effectiveness of the void during the shock impacting.Under the shockwave velocity of 9 km/s,the parent RDX decay rate in RDX entrained amorphous carbon decreases the most and is about one fourth of that in RDX with a vacuum void,and solid HMX and TATB inclusions are more reactive than amorphous carbon but less reactive than dry air or acetone inclusions.The lessdense shocking system denotes the greater increases in local temperature and stress,the faster energy liberation,and the earlier final reaction into equilibrium,revealing more pronounced responses to the present intense shockwave.The quantitative models associated with the relative system density(RD_(sys))were proposed for indicating energy-localization mechanisms and evaluating initiation safety in the shocked crystalline explosive.RD_(sys)is defined by the density ratio of defective RDX to perfect crystal after dynamics relaxation and reveals the global density characteristic in shocked systems filled with chemical inclusions.When RD_(sys)is below 0.9,local hydrodynamic jet initiated by void collapse dominates upon energy localization instead of interfacial impact.This study sheds light on novel insights for understanding the shock chemistry and physical-based atomic origin in crystalline explosives considering chemical-inclusions effects. 展开更多
关键词 Shock responses Energy localization Crystalline explosives chemical inclusions Reactive molecular dynamics
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Valorization of Camellia oleifera oil processing byproducts to value-added chemicals and biobased materials: A critical review
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作者 Xudong Liu Yiying Wu +11 位作者 Yang Gao Zhicheng Jiang Zicheng Zhao Wenquan Zeng Mingyu Xie Sisi Liu Rukuan Liu Yan Chao Suli Nie Aihua Zhang Changzhu Li Zhihong Xiao 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第1期28-53,共26页
The C.oleifera oil processing industry generates large amounts of solid wastes,including C.oleifera shell(COS)and C.oleifera cake(COC).Distinct from generally acknowledged lignocellulosic biomass(corn stover,bamboo,bi... The C.oleifera oil processing industry generates large amounts of solid wastes,including C.oleifera shell(COS)and C.oleifera cake(COC).Distinct from generally acknowledged lignocellulosic biomass(corn stover,bamboo,birch,etc.),Camellia wastes contain diverse bioactive substances in addition to the abundant lignocellulosic components,and thus,the biorefinery utilization of C.oleifera processing byproducts involves complicated processing technologies.This reviewfirst summarizes various technologies for extracting and converting the main components in C.oleifera oil processing byproducts into value-added chemicals and biobased materials,as well as their potential applications.Microwave,ultrasound,and Soxhlet extractions are compared for the extraction of functional bioactive components(tannin,flavonoid,saponin,etc.),while solvothermal conversion and pyrolysis are discussed for the conversion of lignocellulosic components into value-added chemicals.The application areas of these chemicals according to their properties are introduced in detail,including utilizing antioxidant and anti-in-flammatory properties of the bioactive substances for the specific application,as well as drop-in chemicals for the substitution of unrenewable fossil fuel-derived products.In addition to chemical production,biochar fabricated from COS and its applications in thefields of adsorption,supercapacitor,soil remediation and wood composites are comprehensively reviewed and discussed.Finally,based on the compositions and structural characteristics of C.oleifera byproducts,the development of full-component valorization strategies and the expansion of the appli-cationfields are proposed. 展开更多
关键词 Camellia oleifera shell Camellia oleifera cake Value-added chemicals Bioactive components Biobased materials
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Agricultural Contamination of the Surface Waters of the Upper Ouémé in Benin: The Case of Heavy Metals and Pesticides
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作者 Armelle Sabine Yélignan Hounkpatin Nonvignon Martial Fassinou +5 位作者 Fadéby Modeste Gouissi Zoulkanerou Orou Piami Dossou Armel Géraldo Houndeton Souradjou Orou Goura Wakili Bolatito Yessoufou Tayéwo Sylvain Biaou 《Journal of Agricultural Chemistry and Environment》 2024年第1期83-99,共17页
Objective: The main objective of this study was to assess the degree of contamination of surface waters by heavy metals and pesticides. Method: To this end, data were collected in December 2022 from four specific samp... Objective: The main objective of this study was to assess the degree of contamination of surface waters by heavy metals and pesticides. Method: To this end, data were collected in December 2022 from four specific sampling stations: Okpara, Térou, Affon and Adjiro. Levels of heavy metals, including cadmium, chromium, copper, iron, mercury, nickel and lead, were measured and subjected to in-depth statistical analysis using graphical summation models. In addition, the concentrations of pesticide active ingredients present in the samples were interpreted and evaluated. The statistical data collected during this study were processed using R software, version 3.5.0. Results: The values obtained at the different stations Okpara, Térou, Affon and Adjiro are respectively Arsenic (2 × 10<sup>-4</sup> mg/L;2.2 × 10<sup>-1</sup> mg/L;1.2 × 10<sup>-4</sup> mg/L;2 × 10<sup>-4</sup> mg/L), Cadmium (4.4 × 10<sup>-5</sup> mg/L;1.1 × 10<sup>-2</sup> mg/L;10<sup>-4</sup> mg/L;4 × 10<sup>-4</sup> mg/L). Then Copper (7 × 10<sup>-4</sup> mg/L;3 × 10<sup>-3</sup> mg/L;7 × 10<sup>-4</sup> mg/L;1 × 10<sup>-4</sup> mg/L), Iron (1.51 mg/L;6.4 × 10<sup>-1</sup> mg/L;2.0012 mg/L;2.9 × 10<sup>-1</sup> mg/L), Lead (0 mg/L;0 mg/L;1.5 × 10<sup>-3</sup> mg/L;1.5 × 10<sup>-3</sup> mg/L). Mercury, nickel and chromium were not detected in surface waters. It is important to note that the values obtained for trace metals (Cadmium, Chromium, Copper, Iron, Mercury, nickel and chromium were not detected in surface waters. It is important to note that the values obtained for trace metals (cadmium, chromium, copper, iron, mercury, nickel and lead) were all below the guideline standards set by the WHO in 2006 for uncontaminated surface waters. This indicates that the surface waters of the Upper Ouémé were below acceptable contamination thresholds in terms of heavy metals. However, the presence of pesticide active ingredients such as cyfluthrin, endosulfan-alpha, endosulfan-beta, profenosfos, tihan, atrazine, gala super and glycel clearly indicates that these surface waters are subject to agricultural contamination. 展开更多
关键词 Agricultural Contamination Heavy Metals pesticides Surface Water North Benin
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The impact of^(60)Co-γirradiation on the chemical constituents of Chuanxiong Rhizoma
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作者 Ting-Ting Zhu Wei-Shan Qiu +1 位作者 Rui Gu Shi-Hong Zhong 《Traditional Medicine Research》 2024年第1期23-32,共10页
Background:In order to clarify the inmpat ofγirradiation on the chemical composition of traditional Chinese medicine,this paper carefully choosed Chuanxiong Rhizoma to carry on a demonstration study.Methods:Through a... Background:In order to clarify the inmpat ofγirradiation on the chemical composition of traditional Chinese medicine,this paper carefully choosed Chuanxiong Rhizoma to carry on a demonstration study.Methods:Through a meticulous assessment,a comprehensive comparison was made between the irradiated and unirradiated Chuanxiong Rhizoma samples.The property characteristics were investigated by colorimeter and electronic nose.The changes in chemical structures and contents was analyzed by fourier infrared spectroscopy,high performance liquid chromatography and fingerprinting.In a quest to uncover the presence of any new radiolysis products,cutting-edge techniques like ultra performance liquid chromatography-quadrupole-time of flight-mass spectrometry and gas chromatography-mass spectrometry were employed.Moreover,the difference of antioxidant activity were investigated.Results:The irradiation doses within 12 kGy had no significant effects on the content of the main chemical components,characteristics and in vitro antioxidant activity of Chuanxiong Rhizoma,while changes in some functional groups and degradation of some volatile oil components containing olefins need further study.Conclusion:This study indicates that^(60)Co-γirradiation is a stable method for sterilization of Chuanxiong Rhizoma.It’s also provide a reference for the establishment of irradiation standards for Chuanxiong Rhizoma and other aromatic medicinal plants. 展开更多
关键词 ^(60)Co-γirradiation Chuanxiong Rhizoma chemical component comprehensive evaluation
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CO_(2)conversion to solar fuels and chemicals:Opening the new paths
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作者 Gabriele Centi Claudio Ampelli 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第4期680-683,共4页
This future article discusses the new prospects and directions of CO_(2)conversion via the photo-electrocatalytic(PEC)route.The second(2nd)generation solar fuels and chemicals(SFs)are generated directly in PEC systems... This future article discusses the new prospects and directions of CO_(2)conversion via the photo-electrocatalytic(PEC)route.The second(2nd)generation solar fuels and chemicals(SFs)are generated directly in PEC systems via electrons/protons reactions without forming molecular H_(2)as an intermediate,overcoming the thermodynamics limitations and practical issues encountered for electro-fuels produced by multistep thermocatalytic processes(i.e.CO_(2)conversion with H_(2)coming from water electrolysis).A distributed and decentralized production of SFs requires very compact,highly integrated,and intensified technologies.Among the existing reactors of advanced design(based on artificial leaves or photosynthesis),the integrated photovoltaic plus electrocatalytic(PV-EC)device is the only system(demonstrated at large scale)to produce SFs with high solar-to-fuel(STF)efficiency.However,while the literature indicates STF efficiency as the main(and only)measure of process performance,we remark here the need to refer to productivity(in terms of current density)and make tests with reliable flow PEC systems(with electrodes of at least 5–10 cm^(2))to accelerate the scaling-up process.Using approaches that minimize downstream separation costs is also mandatory.Many limitations exist in PEC systems,but most can be overcome by proper electrode and cell engineering,thus going beyond the properties of the electrocatalysts.As examples of current developments,we present the progress of(i)artificial leaf/tree devices for green H_(2)distributed production and(ii)a PEC device producing the same chemicals at both cathode and anode parts without downstream operations for green solvent distributed production.Based on these developments,future directions,such as producing fertilizers and food components from the air,are outlined.The aim is to provide new ideas and research directions from a personal perspective. 展开更多
关键词 Solar fuels Artificial leaf PEC devices PV-EC devices Cell engineering green H_(2) chemicals from theair
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Chemical simulation teaching system based on virtual reality and gesture interaction
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作者 Dengzhen LU Hengyi LI +2 位作者 Boyu QIU Siyuan LIU Shuhan QI 《虚拟现实与智能硬件(中英文)》 EI 2024年第2期148-168,共21页
Background Most existing chemical experiment teaching systems lack solid immersive experiences,making it difficult to engage students.To address these challenges,we propose a chemical simulation teaching system based ... Background Most existing chemical experiment teaching systems lack solid immersive experiences,making it difficult to engage students.To address these challenges,we propose a chemical simulation teaching system based on virtual reality and gesture interaction.Methods The parameters of the models were obtained through actual investigation,whereby Blender and 3DS MAX were used to model and import these parameters into a physics engine.By establishing an interface for the physics engine,gesture interaction hardware,and virtual reality(VR)helmet,a highly realistic chemical experiment environment was created.Using code script logic,particle systems,as well as other systems,chemical phenomena were simulated.Furthermore,we created an online teaching platform using streaming media and databases to address the problems of distance teaching.Results The proposed system was evaluated against two mainstream products in the market.In the experiments,the proposed system outperformed the other products in terms of fidelity and practicality.Conclusions The proposed system which offers realistic simulations and practicability,can help improve the high school chemistry experimental education. 展开更多
关键词 chemical experiment simulation Gesture interaction Virtual reality Model establishment Process control Streaming media DATABASE
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Chemically Radiative MHD Flow of a Micropolar Nanofluid over a Stretching/ Shrinking Sheet with a Heat Source or Sink
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作者 Parakapali Roja Shaik Mohammed Ibrahim +1 位作者 Thummala Sankar Reddy Giulio Lorenzini 《Fluid Dynamics & Materials Processing》 EI 2024年第2期257-274,共18页
This study examines the behavior of a micropolar nanofluidflowing over a sheet in the presence of a transverse magneticfield and thermal effects.In addition,chemical(first-order homogeneous)reactions are taken into accoun... This study examines the behavior of a micropolar nanofluidflowing over a sheet in the presence of a transverse magneticfield and thermal effects.In addition,chemical(first-order homogeneous)reactions are taken into account.A similarity transformation is used to reduce the system of governing coupled non-linear partial differ-ential equations(PDEs),which account for the transport of mass,momentum,angular momentum,energy and species,to a set of non-linear ordinary differential equations(ODEs).The Runge-Kutta method along with shoot-ing method is used to solve them.The impact of several parameters is evaluated.It is shown that the micro-rota-tional velocity of thefluid rises with the micropolar factor.Moreover,the radiation parameter can have a remarkable influence on theflow and temperature profiles and on the angular momentum distribution. 展开更多
关键词 chemical(first order homogeneous)reaction MAGNETOHYDRODYNAMICS MICROPOLAR NANOFLUID stretching/shrinking sheet heat source
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Chemical constituents and pharmacological effects of Lonicerae japonicae
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作者 Yunpeng Yang Dan Tian +3 位作者 Yibo Wang Yi’an Shi Yuntian Xing Yu Chen 《Asian Journal of Traditional Medicines》 2024年第1期34-45,共12页
Lonicera japonica,also known as honeysuckle,is an evergreen shrub in the family of Syzygium.By consulting Sciencedirect databases and Web of Science databases,79 related articles were found,of which 22 were related to... Lonicera japonica,also known as honeysuckle,is an evergreen shrub in the family of Syzygium.By consulting Sciencedirect databases and Web of Science databases,79 related articles were found,of which 22 were related to chemical composition and pharmacological activity.These articles show that L.japonica has a wide range of pharmacological activities,including antiviral,anti-tumor,and antioxidant effects.These activities have important applications in the pharmaceutical,food,and fragrance industries.This review focuses on the chemical composition and pharmacological effects of L.japonicae,which is of great significance to the development of new drugs and therapeutic methods. 展开更多
关键词 Lonicerae japonicae chemical composition pharmacological activity
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