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Effects of neutral salt and alkali on ion distributions in the roots,shoots,and leaves of two alfalfa cultivars with differing degrees of salt tolerance

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Journal of Integrative Agriculture 2017年第8期16卷 1800-1807页

作者： WANG Xiao-shan ren Hai-long wei Zen-wu WANG Yun-wen ren wei-bo Department of Grassland Science College of Animal Science and TechnologyYangzhou UniversityYangzhou 225009P.R.China Institute of Grassland Research Chinese Academy of Agricultural SciencesHohhot 010000P.R.China Department of Grassland Science College of Animal Science and TechnologyChina Agricultural UniversityBeijing 100193P.R.China

The effects of neutral salt and alkali on the ion distribution were investigated in two alfalfa （Medicago sativa L.） cultivars, including Zhongmu 1, a high salt-tolerant cultivar, and Algonquin, a low salt-tolerant cultivar. The alkali stress expressed more serious growth inhibition than the neutral salt stress at the same Na＋ concentration. Compared with Algonquin, Zhongmu 1 did not exhibit a higher alkali tolerance under the Na2CO3-NaHCO3 treatment with the low Na＋ concentration （50 mmol L-l）. The alkali increased the accumulation of Na＋, Ca2＋, and Mg2＋ in the root and changed the Ca2＋ and Mg2＋ balance in the entire alfalfa plant. The salt and alkali stresses decreased the K＋ and Fe3＋ contents of the roots and leaves, the root Mn2＋ content, and the shoot Zn2＋ content, but they increased the Fe3＋ accumulation of the shoots, the shoot and leaf Cu2＋ contents, and the leaf Zn2＋ content in both alfalfa cultivars. Based on the results obtained under the conditions of this experiment, we found that the salt and alkali stresses reduced the plant growth in both alfalfa cultivars, while the alkali caused a stronger stress than the neutral salt in alfalfa. Thus, we conclude that under hydroponic conditions, the deleterious effects of the alkali on plants are due to the distribution change of some trophic ion balance in the roots, shoots, and leaves of the plants by causing of Na＋, CO3^2-, and/or HCO3- stresses.

关键词： alfalfa ion distribution neutral salts alkali stress

Synthesis, self-assembly and photo-responsive behavior of AB_2 shaped amphiphilic azo block copolymer

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Chinese Chemical Letters 2015年第7期26卷 857-861页

作者： ren-bo wei Xiao-Gong Wang Ya-Ning He Department of Chemical Engineering Key Laboratory of Advanced Materials (MOE) Tsinghua University

In this work, we report the synthesis of AB2 shaped amphiphilic azo block copolymer by macromolecular azo coupling reaction. The product and intermediates were characterized by various methods. The self- assembly in selected solvents and photo-responsive behavior of the copolymer were studied by means of UV-vis spectrophotometry and TEM. Spherical aggregates can be obtained by gradually adding water into the solution of this amphiphilic azo block copolymer. Upon irradiation with polarized UV （365 nm） light, the aggregates can be elongated in the polarized direction.

关键词： Azo block copolymerSelf-assemblySpherical aggregatesPhotoinduced deformationMacromolecular azo-coupling reaction

A novel fluorescent epoxy resin for organophosphate pesticide detection

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Chinese Chemical Letters 2015年第1期26卷 39-42页

作者： Hong-Xing Zhang ren-bo wei Chuan-Zhi Chen Xin-Lin Tuo Xiao-Gong Wang Department of Chemical Engineering Laboratory of Advanced Materials(MOE)Tsinghua University Department of Chemical Defense Institute of Chemical Defense

In this work,a novel bisbenzimidazolylpyridine-functionalized fluorescent epoxy resin was synthesized for organophosphate pesticide *** epoxy resin was characterized by Fourier-transform infrared spectroscopy（FT-IR）,proton nuclear magnetic resonance spectroscopy（~1H NMR）,gel permeation chromatography（CPC）,differential scanning calorimetry（DSC） and fluorescence *** loading with Eu（Ⅲ） ions,the epoxy resin showed a strong fluorescence *** fluorescence emission was observed to be instantaneously quenched when exposed to trace amount of diethyl chlorophosphate in *** Stern-Volmer quenching constants Ksv for quenching at617 nm was determined to be 0.377 × 10^3 L/*** sensitive emission-quenching function and easy processing nature of the polymeric support enable the resin to be a promising chemosensor candidate for the detection of organophosphates.

关键词： MeBIP Epoxy resin Europium complex Fluorescence quenching Organophosphates

Recovery of Li, Ni, Co and Mn from spent lithium-ion batteries assisted by organic acids: Process optimization and leaching mechanism

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International Journal of Minerals,Metallurgy and Materials 2024年第3期31卷 518-530页

作者： Liuyi ren bo Liu Shenxu Bao wei Ding Yimin Zhang Xiaochuan Hou Chao Lin bo Chen School of Resources and Environmental Engineering Wuhan University of TechnologyWuhan 430070China State Environmental Protection Key Laboratory of Mineral Metallurgical Resources Utilization and Pollution Control Wuhan University of Science and TechnologyWuhan 430081China Zhejiang New Era Zhongneng Recycling Technology Co. LtdShaoxing 312000China Shenzhen Water Planning&Design Institute Co. LtdShenzhen 518000China

The proper recycling of spent lithium-ion batteries(LIBs)can promote the recovery and utilization of valuable resources,while also negative environmental effects resulting from the presence of toxic and hazardous *** this study,a new environmentally friendly hydro-metallurgical process was proposed for leaching lithium(Li),nickel(Ni),cobalt(Co),and manganese(Mn)from spent LIBs using sulfuric acid with citric acid as a *** effects of the concentration of sulfuric acid,the leaching temperature,the leaching time,the solid-liquid ratio,and the reducing agent dosage on the leaching behavior of the above elements were *** parameters were optimized using response surface methodology(RSM)to maximize the recovery of metals from spent *** maxim-um recovery efficiencies of Li,Ni,Co,and Mn can reach 99.08%,98.76%,98.33%,and 97.63%.under the optimized conditions(the sulfuric acid concentration was 1.16 mol/L,the citric acid dosage was 15wt%,the solid-liquid ratio was 40 g/L,and the temperature was 83℃ for 120 min),*** was found that in the collaborative leaching process of sulfuric acid and citric acid,the citric acid initially provided strong reducing CO_(2)^(-),and the transition metal ions in the high state underwent a reduction reaction to produce transition metal ions in the low ***,citric acid can also act as a proton donor and chelate with lower-priced transition metal ions,thus speeding up the dissolution process.

关键词： spent lithium-ion batteries leaching response surface methodology sulfuric acid citric acid

Linking nutrient strategies with plant size along a grazing gradient： Evidence from Leymus chinensis in a natural pasture

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Journal of Integrative Agriculture 2016年第5期15卷 1132-1144页

作者： LI Xi-liang LIU Zhi-ying ren wei-bo DING Yong JI Lei GUO Feng-hui HOU Xiang-yang National Forage Improvement Center/Key Laboratory of Grassland Resources and Utilization Ministry of Agriculture/Institute of Grassland Research Chinese Academy of Agricultural Sciences Hohhot 010010 P.R.China

St udying the changes in nutrient use strategies induced by grazing can provide insight into the process of grassland degradation and is important for improving grassland quality and enhancing ecosystem function. Dominant species in meadow steppe can optimize their use of limiting resources; however, the regulation of nutrient use strategies across grazing gradients is not fully understood. Therefore, in this study, we report an in situ study in which the impact of grazing rates on nutrient use strategies of Leymus chinensis, the dominant plant species in eastern Eurasian temperate steppes, was investigated. We conducted a large randomized controlled experiment（conducted continuously for five years in grassland plots in a natural pasture in Ha ilar, eastern Mongolia Plateau, China） to assess the effects of grazing rate treatments（0.00, 0.23, 0.34, 0.46, 0.69, and 0.92 adult cattle unit（AU） ha-1） on L. chinensis along a grazing gradient and employed a random sampling approach to compare the accumulation, allocation, and stoichiometry of C, N, and P in leaves and stems. Ou r findings demonstrated the follows：（i） The height of L. chinensis decreased with an increase in the grazing gradient, and the concentrations of C, N, and P significantly increased;（ii） the accumulation of C, N, and P per individual was negatively correlated with the concentration of aboveground tissues, suggesting that there was a tradeoff in L. chinensis between nutrient accumulation and concentration at the individual scale;（iii） the leaf-to-stem ratio of C, N, and P accumulation increased with grazing intensity, indicating a tradeoff in nutrient allocation and plant size at the individual plant level; and（iv） grazing rates were negatively correlated with the ratios of C：N and C：P in the stem; however, these ratios in leaves significantly increased with grazing intensity. Our findings suggest that L. chinensis in meadow steppe adapts to grazing disturbance through tradeoffs between plant size and

关键词： meadow steppe nutrient-use strategy overgrazing stoichiometry Inner Mongolia Leymus chinensis

Impact of Climate and Grazing on Biomass Components of Eastern Russia Typical Steppe

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Journal of Integrative Agriculture 2014年第6期13卷 1183-1192页

作者： Ubugunov Leonid Rupyshev Yuriy Ubugunov Vasiliy HOU Xiang-yang Vishnyakova Oxana Lavrentieva Irina Ubugunova Vera ren wei-bo DING Yong Institute of General and Experimental Biology Siberian Branch of Russian Academy of Sciences Grassland Research Institute Chinese Academy of Agricultural Sciences

Spatial and structural characteristics of plant communities in the steppe ecosystems of the Baikal region, Russian Federation have been researched in connection with climate change and grazing. The present study, based on a total of 15 typical steppe sampling plots, investigated above-ground biomass （AGB）, below-ground biomass （BGB）, total biomass （TB） and root：shoot ratios （R：S） and their relationships with climatic factors and grazing. All biomass components varied widely depending on the climatic parameters and the degree of grazing affected transformation. A strong negative correlation between mean annual temperature （MAT） and total plant biomass was revealed for all study area. Mean annual precipitation （MAP） signiifcantly affected communities productivity increasing only in the south of the region. Due to the large and mountainous territory, the inlfuence of latitude and elevation （mountain） factors on the components of the biomass were studied. Although all studied plant steppe communities were transformed by uncontrolled grazing, their productivity is signiifcantly reduced only at plots with maximum digression. Vegetation shift is an indicator of climate change, as well as providing a diagnostic tool to build predictive models. Based on the complex index of effective precipitation, it was revealed that at the end of last century in the steppes of the Baikal region the structural and production processes will be affected by an arid climate trend.

关键词： steppe productivity climate grazing transformation Baikal region

Acaricidal effect of the antimicrobial metabolite xenocoumacin 1 on spider mite control

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Journal of Integrative Agriculture 2024年第3期23卷 948-959页

作者： Jiaxing wei Hong Yan Jie ren Guangyue Li bo Zhang Xuenong Xu Institute of Plant Protection Chinese Academy of Agricultural SciencesBeijing 100193China State Key Laboratory for Biology of Plant Diseases and Insect Pests Beijing 100193China Key Laboratory of Natural Enemies Insects Ministry of Agriculture and Rural AffairsBeijing 100193China

The two-spotted spider mite,Tetranychus urticae Koch,is one of the most harmful pests in many agroecosystems *** effectively manage this pest,there is an urgent need to develop novel bio-active acaricides that support integrated pest management strategies targeting *** this study,we explored the acaricidal effects of xenocoumacin 1 (Xcn1) on *** and its predator Neoseiulus californicus using the highly puri?ed ***1 was extracted and purified from the cell-free supernatant of the Xenorhabdus nematophila CB6 mutant constructed by the easy promoter activated compound identi?cation (easyPACId) *** the concentration of Xcn1 exceeded 100μg mL~(–1),the survival rate of spider mite adults declined to below 40%and the fecundity was decreased by 80%at six days *** concentrations of 25 and 50μg mL~(–1),Xcn1 signi?cantly impeded spider mite development by inhibiting the ***,neither concentration had any adverse effects on the survival or reproduction of the predatory mite *** results from laboratory and semi-?eld experiments consistently demonstrated the effectiveness of the antimicrobial metabolite Xcn1 in controlling pest mites at both the molecular and physiological *** study offers a promising possibility that combines the compatible biocontrol agents of Xcn1 and predatory mites for integrated pest mite control.

关键词： pest management predatory mite Xcn1 morphology developmental inhibition transcriptome

Nonlocal symmetries,soliton-cnoidal wave solution and soliton molecules to a(2+1)-dimensional modified KdV system

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Communications in Theoretical Physics 2024年第4期76卷 14-21页

作者： Jianyong Wang bo ren Department of Mathematics and Physics Quzhou UniversityQuzhou 324000China Department of Mathematics Zhejiang University of TechnologyHangzhou 310014China

A(2+1)-dimensional modified KdV(2DmKdV)system is considered from several ***,residue symmetry,a type of nonlocal symmetry,and the Bäcklund transformation are obtained via the truncated Painlevéexpansion ***,the residue symmetry is localized to a Lie point symmetry of a prolonged system,from which the finite transformation group is ***,the integrability of the 2DmKdV system is examined under the sense of consistent tanh expansion ***,explicit soliton-cnoidal wave solutions are ***,abundant patterns of soliton molecules are presented by imposing the velocity resonance condition on the multiple-soliton solution.

关键词： soliton-cnoidal wave solution nonlocal symmetry soliton molecule (2+1)-dimensional modified KdV system

An integrated MINLP model for multi-party coordination in downstream oil supply chain

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Petroleum Science 2024年第3期21卷 2066-2079页

作者： Rui Qiu bo Zhang wei Zhao ren-Fu Tu Man-Qiu He Qi Liao Yong-Tu Liang National Engineering Laboratory for Pipeline Safety/Beijing Key Laboratory of Urban Oil and Gas Distribution Technology China University of Petroleum-BeijingFuxue Road No.18Changping DistrictBeijing102249PR China Strategy&Implementation Department PipeChinaDongtucheng Road No.5Chaoyang DistrictBeijing100013PR China

Cooperation among enterprises can bring overall and individual performance improvement,and a smooth coordination method is ***,due to the lack of customized coordination methods,cooperation in the downstream oil supply chain cannot be carried out *** paper intends to propose a multi-party coordination method to promote cooperation between oil shippers and pipeline operator by optimizing oil transportation,oil substitution and pipeline pricing *** integrated game-theoretic modeling and analysis approach is developed to characterize the operation behaviors of all stakeholders in the downstream oil supply *** proposed mixed integer nonlinear programming model constrains supply and demand capacity,transportation routes,oil substitution rules and pipeline freight *** transformation and price discretization are introduced for model linear *** experiments are carried out in the oil distribution system in South *** results show that compared to the business-as-usual scheme,the new scheme saves transportation cost by 3.48%,increases pipeline turnover by 5.7%,and reduces energy consumption and emissions by 7.66%and 6.77%.It is proved that the proposed method improves the revenue of the whole system,achieves fair revenue distribution,and also improves the energy and environmental benefits of the oil supply chain.

关键词： Downstreamoil supplychain Multi-partycoordination Cooperative game Mixed integernonlinear programming model Pipeline transportation Revenue distribution