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Experimental study on photodegradation and leaching of typical pesticides in greenhouse soil from Shouguang, Shandong Province, East China

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Ecological Processes 2024年第2期 32-47页

作者： li-ting hua Rui-lin Wu Cun-Lu li Chao-Nan Wang Yi-Long li Fu-liu Xu MOE Laboratory for Earth Surface Processes College of Urban and Envi-ronmental Sciences Peking University Department of Ecology and Environment of Shanxi Province

Background Pesticide use contributes to national food security. The dissipation pathways and degradation mecha-nisms of pesticides have been widely studied and pesticide residues have remained a focus of public concern. How-ever, studies on the migration and transformation behaviors of pesticide residues in real-world greenhouse soils are insufficient. Therefore, in this study, we collected greenhouse soil from Shouguang, Shandong Province, and investi-gated the photodegradation and leaching of 17 common pesticides, which leave residues in the soil and are the most frequently used pesticides in Shouguang. The environmental behavior of pesticides in greenhouse soils will provide new information on pesticide residues in the real environment and provide a scientific basis for the prevention and control of pesticide pollution in greenhouse *** The photodegradation of trifloxystrobin followed a first-order kinetic equation, whereas those of emamec-tin benzoate, chlorantraniliprole, buprofezin, difenoconazole, pyraclostrobin, boscalid, tebuconazole, isoprothiolane, metalaxyl, and oxadixyl followed second-order kinetics. The half-lives of 17 pesticides under light and dark conditions ranged from 2.5–104(mean: 36.2) and 2.6–110(mean: 31.4) days, respectively. The half-lives of emamectin benzoate, pyraclostrobin, and metalaxyl in the light were 86.6%, 68.5%, and 94.5% of their half-lives in the dark, respectively. Chlorantraniliprole, metalaxyl, nitenpyram, diethofencarb, acetamiprid, carbendazim, and oxadixyl were leached to ≥ 90% in aqueous solution. Six pesticides, avermectin B1A, emamectin benzoate, trifloxystrobin, difenoconazole, pyraclostrobin, and buprofezin, were difficult to leach from aqueous *** The degradation rate of some pesticides was higher in the light environment than in the dark. The leaching potential of the leachable pesticides was nitenpyram ? metalaxyl > acetamiprid > carbendazim > diethofen-carb ≈ chlorantraniliprole > iso

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NUMERICAL SIMULATION OF TURBULENT JETS WITH LATERAL INJECTION INTO A CROSSFLOW

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Journal of Hydrodynamics 2006年第3期18卷 319-323页

作者： GUO ting-ting li Shao-hua XU Zhong Department of＇Energy and mechanical Engineering Northeast Dianli University Jilin 132012 China School of Energy and Power Engineering Xi＇an Jiaotong UniversityXi＇an 710049China

In this paper, Numerical simulations of mean velocity and turbulent kinetic energy fields are presented for three-dimensional lateral jet in crossflow, at the injection angles of -60° and -30 °. The RNG κ- ε turbulence model, with the two-layer wall function method, is adopted to simulate the characteristics of this flow at the jet-to-crossflow velocity ratios, 1, 2 and 4. The results show that the injection angle and jet-to-crossflow velocity ratio can change the flow fields, and the range upstream affected by jet injected laterally increase and the curvature of jet trajectories varies along the flow direction. Furthermore, the separation events in the lee of the jet exit and behind the jet bending-segment have been found, and the mechanisms of two vortex systems are analyzed.

关键词： turbulent jet turbulence model numerical simulation flow field

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静电纺丝技术制备料香包埋材料及其性能研究

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四川大学学报（自然科学版） 2024年第4期61卷 280-286页

作者：李志强雷萍艾璞李廷华李寿波朱东来尚善斋李晖孙巧媚云南中烟工业有限责任公司技术中心昆明650231 四川大学化学工程学院成都610065

本研究针对加热卷烟滤嘴料香挥发性强、有效释放率低的问题,利用壳聚糖和聚己内酯通过静电纺丝和加热混合包埋技术,成功制备了新型料香包埋材料.通过红外光谱、热重分析和气相色谱等测试,评估了该材料的结构、留着率、释放性能及稳定性... 详细信息

本研究针对加热卷烟滤嘴料香挥发性强、有效释放率低的问题,利用壳聚糖和聚己内酯通过静电纺丝和加热混合包埋技术,成功制备了新型料香包埋材料.通过红外光谱、热重分析和气相色谱等测试,评估了该材料的结构、留着率、释放性能及稳定性.结果表明,该材料对薄荷醇的负载率高达59.72%,常温留着率达78.58%,抽吸时的释放率超过85%,在14 d稳定性测试中,薄荷醇留存率较晶体形态提高15%.细胞实验进一步验证了其高生物相容性和低浓度依赖性的优势.这一研究为提升加热卷烟滤嘴的香料释放效率和感官品质提供了新策略.

关键词：加热卷烟料香静电纺丝薄荷醇释放率

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A rapid and accurate 3-(4,5-dimethyl thiazol-2-yl)-2,5-diphenyl tetrazolium bromide colorimetric assay for quantification of bacteriocins with nisin as an example

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2007年第8期8卷 549-554页

作者： WANG Fang CAO li-ting HU Song-hua Department of Veterinary Medicine College of Animal Sciences Zhejiang University Hangzhou 310029 China

The objective of this study is to propose a more accurate and faster MTT 3-(4,5-dimethyl thiazol-2-yl)-2,5-diphenyl tetrazolium bromide colorimetric assay (MCA) for quantitative measurement of polypeptide bacteriocins in solutions with nisin as an example. After an initial incubation of nisin and indicator bacterium Micrococcus luteus NCIB 8166 in tubes, MTT was added for another incubation period. After that, nisin was quantified by estimating the number of viable bacteria based on measuring the amount of purple formazan produced by cleavage of yellow tetrazolium salt MTT. Then MCA was compared to a standard agar diffusion assay (ADA). The results suggested a high correlation coefficient (r2=0.975±0.004) between optical density (OD) and the inhibitory effect of nisin on a bacterial strain Micrococcus luteus NCIB 8166 at a range of 0.125～32 IU/ml. The MCA described in this study was very quick. Quantification of nisin took only 7～8 h and the detection limit was at the level of 0.125 IU/ml when compared to 12 IU/ml and 24～28 h for ADA. The MCA provides an accurate and rapid method for quantifi-cation of nisin in solutions and is expected to be used for quantification of other antimicrobial substances.

关键词： MTT colorimetric assay Nisin Micrococcus luteus

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Local tetragonal distortion of Pt alloy catalysts for enhanced oxygen reduction reaction efficiency

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Carbon Energy 2024年第7期6卷 41-52页

作者： Xiaoke li Xiao Duan Kang hua Yongkang Wu Zhiyan Rui Rui Ding Aidong li Chen Ouyang Jia li ting li Jianguo liu National Laboratory of Solid-State Microstructures College of Engineering and Applied Sciencesand Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjingChina Long-life Fuel Cell Key Laboratory in Sichuan Province Dongfang Electric(Chengdu)Hydrogen Fuel Cell Technology Co.Ltd.ChengduChina Institute of Energy Power Innovation North China Electric Power UniversityBeijingChina

Platinum-based alloy nanoparticles are the most attractive catalysts for the oxygen reduction reaction at present,but an in-depth understanding of the relationship between their short-range structural information and catalytic performance is still ***,we present a synthetic strategy that uses transition-metal oxide-assisted thermal ***/C catalysts with localized tetragonal distortion were obtained by controlling the thermal diffusion process of transition-metal *** localized structural distortion induced a significant strain effect on the nanoparticle surface,which further shortened the length of the Pt-Pt bond,improved the electronic state of the Pt surface,and enhanced the performance of the ***/C catalysts with special short-range structures achieved excellent mass activity(2.27 Amg_(Pt)^(-1))and specific activity(3.34 A cm^(-2)).In addition,the localized tetragonal distortion-induced surface compression of the Pt skin improved the stability of the *** mass activity decreased by only 13%after 30,000 *** catalyst activity and excellent durability have also been demonstrated in the proton exchange membrane fuel cell *** study provides valuable insights into the development of advanced Pt-based nanocatalysts and paves the way for reducing noble-metal loading and increasing the catalytic activity and catalyst stability.

关键词： electrocatalysts fuel cells local tetragonal distortion oxygen reduction

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Geochemistry and Zircon U-Pb and Hf Isotopes of Early Devonian Hardawu Granites in the Eastern Segment of the Ultrahigh-Pressure Metamorphic Belt, Northern Qaidam Basin

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Journal of Earth Science 2024年第3期35卷 866-877页

作者： hua li Ming Wang Jiqing li Haikui Tong Jiaxiang Dong Minggang Tian Xiaolin Chen Leguang li ting Xie Xiong li Yuying Che Qinghai Geological Survey Xining 810000China Technology Innovation Center for Exploration and Exploitation of Strategic Mineral Resources in Plateau Desert Region Ministry of Natural ResourcesXining 810000China Qinghai Geological Survey Institute Xining 810000China Geological Exploration Institute of Shandong Zhengyuan Jinan 271000China School of Earth Science China University of GeosciencesWuhan 430074China

The Hardawu granites in the eastern segment of the ultrahigh-pressure metamorphic belt,the northern Qaidam Basin,were studied by whole-rock major and trace elements and in-situ zircon U-Pb geochronology and Hf isotopes to discuss the petrogenesis and tectonic *** results show that the granites have a crystallization age of 401±3 Ma,suggesting that they were formed in the Early *** granites have SiO2 contents of 75.32 wt.%-76.05 wt.%,total alkali contents of 8.23 wt.%-8.36 wt.%,and K2O/Na2O ratios of *** were rich in K2O,poor in TiO2,MnO,MgO,and P2O5,and have A/CNK values of 1.05-1.07,Rittmann indexδvalues of 2.05-2.14,and differentiation index(DI)values of *** are high potassium calc-alkaline,weakperaluminum,and highly differentiated I-type *** granites also show enrichment of large ion lithophile elements(liLE)such as Rb,Ba,and Th,and depletion of high field strength elements(HFSE)such as Nb,Ta,and *** total REE concentrations range from 169 ppm to 232 ppm,with enrichments of light rare earth elements and negative Eu anomalies(δEu=0.39-0.55).The zirconεHf(t)values range from-0.65 to-2.29,and the two-stage model ages(tDM2)changed within a small range of 1.44 to 1.54 Ga,indicating that the magma of the Hardawu granites was originated from the partial melting of Mesoproterozoic lower crustal *** with previous studies,we suggest that the Hardawu granites were formed in the extensional tectonic setting after the collision between the Qaidam Block and the central and southern Qilian Block in the Early Devonian.

关键词： granite Early Devonian petrogenesis tectonic implication Qaidam Basin geochemistry

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Seasonal response of nitrogen exchange fluxes to crab disturbance at sediment-water interface in coastal tidal wetlands

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Water Science and Engineering 2024年第2期17卷 129-138页

作者： Guo-fen hua Shang-qing liu Xiang-dong liu Jin-li li Yue Fang Wen-ting Xie Xiang Xu College of Water Conservancy and Hydroelectric Power Hohai UniversityNanjing 210098China College of Renewable Energy Hohai UniversityNanjing 210098China

Coastal wetlands are hotspots for nitrogen(N)cycling,and crab burrowing is known to transform N in intertidal marsh ***,the underlying mechanisms remain *** study conducted field experiments and used indoor control test devices to investigate the seasonal response of nitrogen to crab disturbance at the sediment-water interface in coastal tidal flat *** results showed that crab disturbance exhibited significant seasonality with large seasonal differences in cave density and *** to crab disturbance,nitrogen fuxes at the sediment-water interface were much greater in the box with crabs than in the box without *** summer,NH-N showed a positive flux from the sediment to the overlying water,but NO2-N and NOg-N showed positive fluxes from the sediment to the overlying water only in early *** winter,NH-N showed a positive flux from the sediment to the overlying water,but NO-N and NO,-N both exhibited positive and negative *** results indicated that the presence of crab burrows can cause the aerobic layer to move downward by approximately 8-15 cm in summer and directly promote nitrification at the sediment surface.

关键词： Coastal tidal flat wetland Crab disturbance Nitrogen flux Nitrification Denitrification Sediment-water interface

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Role of Fibroblast Growth Factor 19 in Maintaining Nutrient Homeostasis and Disease

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Biomedical and Environmental Sciences 2014年第5期27卷 319-324页

作者： ZHANG Jing li hua ting FANG Qi Chen JIA Wei Ping Department of Endocrinology and Metabolism Shanghai Jiao Tong University Affiliated Sixth People’s Hospital Shanghai Diabetes Institute Shanghai Key Laboratory of Diabetes Mellitus Shanghai Clinical Center for Diabetes Department of Medicine Shanghai Jiao Tong University School of Medicine

Fibroblast growth factor 19 （FGF19） is a kind of gut-derived postprandial hormone. As an atypical member of the FGF family, FGF19 functions as an endocrine hormone except regulating cell growth and differentiation. FGF19 plays a key role in coordination of liver bile acid biosynthesis and gallbladder motility, and acts as a regulator of metabolic homeostasis, including strengthening insulin sensitivity, decreasing triglyceride concentration and reducing body weight.

关键词： FGFs acid FGFR Role of Fibroblast Growth Factor 19 in Maintaining Nutrient Homeostasis and Disease

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Tough Polymeric Hydrogels Based on Amino Acid Derivative Mediated Dynamic Metal Coordination Bonds

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Chinese Journal of Polymer Science 2024年第10期42卷 1578-1588,I0014页

作者： Meng li Meng-Yuan Zhang Wu-Xuan Lei Zhu-ting Lv Qing-hua Shang Zheng Zhao Jiang-Tao li Yi-Long Cheng Engineering Research Center of Energy Storage Materials and Devices Ministry of EducationSchool of ChemistryXi’an Jiaotong UniversityXi’an710049China Polymer Materials&Engineering Department School of Materials Science&Engineering Chang’an UniversityXi’an710064China School of Electrical Engineering Xi’an Jiaotong UniversityXi’an710049China Department of Nuclear Medicine the First Affiliated Hospital of ChinaXi’an Jiaotong UniversityXi’an710049China

Abstract The development of physically crosslinked hydrogels with excellent mechanical and sensing properties is of importance for expanding the practical applications of intelligent soft hydrogel ***,after copolymerization of hydroxyl-containing amino acid derivative N-acryloyl serine(ASer)with acrylamide(AM),we introduce Zr4+through an immersion strategy to construct metal ion-toughened non-covalent crosslinked hydrogels(with tensile strength of up to 5.73 MPa).It is found that the synergistic coordination of hydroxyl and carboxyl groups with Zr^(4+)substantially increases the crosslinking density of the hydrogels,thereby imparting markedly superior mechanical properties compared to hydroxyl-free Zr^(4+)-crosslinked hydrogels,such as N-acryloyl alanine(AAla)copolymerized with AM hydrogels(with tensile strength of 2.98 MPa)Through the adjustment of the composition of the copolymer and the density of coordination bonds,the mechanical properties of the hydrogels can be modulated over a wide ***,due to the introduction of metal ions and the dynamic nature of coordination bonds,the hydrogels also exhibit excellent sensing performance and good self-recovery properties,paving the way for the development of flexible electronic substrates with outstanding comprehensive performances.

关键词： Hydrogel Amino acid Metal coordination Mechanical performance Flexible sensor

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A two-pronged strategy utilizing exosomes extracted from antigenpresenting cells to combat hepatitis B

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Nano Research 2024年第10期17卷 9084-9094页

作者： Fumin Hu Dangyang Wang ting Lu Guanghui Ma hua Yue State Key Laboratory of Biochemical Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Biopharmaceutical Preparation and Delivery Chinese Academy of SciencesBeijing 100190China

Chronic hepatitis B(CHB)is consistently challenging to conquer with numerous complications and *** the effectiveness of antiviral therapies in suppressing hepatitis B virus(HBV)replication,there is an urgent need for novel and more effective treatment *** strategies predominantly emphasize immune activation but still face challenges in sufficiently eliciting T cell *** into account the targeted delivery of nanoparticles to the liver and spleen via intravenous injection,we have proposed a dual-pronged therapeutic strategy based on antigen-presenting cells(APCs)-derived ***,exosomes targeted to the spleen can activate specific immune responses,while those targeted to the liver can modulate or reverse the liver’s immunosuppressive *** immunization,exosome formulations exhibit the remarkable ability to effectively activate APCs,thereby triggering the proliferation of CD8^(+)T ***,they also play an immunoregulatory role by converting M2 macrophages into M1 *** two-pronged therapeutic strategy precisely addresses the issues of T cell dysfunction and immune suppression,both characteristic features of CHB *** combined with Aluminum(Alum)-adjuvanted vaccine,these exosome formulations not only demonstrate a high level of cellular immune response but also secrete specific antibodies comparable to those induced by Alum *** combined approach effectively enhances both cellular and humoral immunity,offering a promising avenue for the development of therapeutic hepatitis B vaccines based on exosome formulations.

关键词： chronic hepatitis B antigen-presenting cells(APCs)-derived exosomes immunoregulatory role two-pronged therapeutic strategy

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