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Atmospheric deposition fluxes and health risk assessment of potentially toxic elements in Caohai Lake(Guizhou Province,China)

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Journal of Mountain Science 2022年第4期19卷 1107-1118页

作者： LIN Shao-xia zhang Zhuan-ling xiao Zhi-qiang LIU xiao-lan zhang Qing-hai State Key Laboratory of Functions and Applications of Medicinal Plants Guizhou Medical UniversityGuiyang 550014China The Key Laboratory of Chemistry for Natural Products of Guizhou Province and Chinese Academy of Science Guiyang 550014China Guizhou Academy of Testing and Analysis Guiyang 550014China Guizhou University Guiyang 550025China Guizhou Medical University Guiyang 550025China

In this study,the sources of potentially toxic elements(PTEs)from atmospheric deposition in the waters of Guizhou’s Caohai Lake were investigated in addition to the potential risks to human *** bags were used to enrich PTEs from atmospheric deposition,and eight monitoring sites that best represented geographic variation were established around Caohai *** bags were collected and examined at every 3 months to identify spatiotemporal patterns of dry and wet atmospheric deposition of *** was the most abundant metal identified from deposition in Caohai(72.07%–95.94%),followed by Pb and Cd,while Hg was the least abundant(0.008%–0.354%).The contributions of wet deposition of PTEs were greater than those of dry deposition,and deposition during the heating season from December to April was greater than that between April to *** was mainly derived from atmospheric dry deposition(65.38%–84.44%).Spatial distribution analysis indicated that atmospheric deposition was associated with the intensity of human activities and heating *** via hand-to-mouth contact accounted for over 99%of the total exposure risk although overall exposure was lower than threshold acceptable levels for carcinogenic and non-carcinogenic metals,indicating an overall lack of risk towards human ***,the health risk from atmospheric deposition of PTEs in Caohai Lake may be reduced by focusing on Zn,Pb,and Cd deposition in rainfall and minimizing the hazards associated with hand-to-mouth exposure to PTEs.

关键词： Caohai Lake Potentially toxic elements(PTEs) Atmospheric deposition Health risk assessment Heavy metals

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Influencing Factors on Rice Sheath Blight Epidemics in Integrated Rice-Duck System

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Journal of Integrative Agriculture 2012年第9期11卷 1462-1473页

作者： SU Pin LIAO xiao-lan zhang Ya HUANG Huang College of Bio-Safety Science and Technology Hunan Agricultural University Changsha 410128 P.R.China College of Agronomy Hunan Agricultural University Changsha 410128 P.R.China

Sheath blight, a disease caused by the fungus Rhizoctonia solani Kuhn （anamorph）, has been the most economically significant disease of rice. It was frequently reported that the disease was well-controlled in integrated rice-duck system without the employment of fungicides. However, the effecting factors behind this phenomenon were rarely reported. In this research, experiment was carried out between two treatments, rice combined with ducks （RD） and conventional rice field without ducks rearing （CK） in early season rice paddy, to investigate the variations of sclerotia in floodwater and on rice plant, microclimate 10 cm above the waterline in rice paddy and activity of protective enzymes in rice plants. The results showed that the floating sclerotia in floodwater in RD was 86-91% lower than that in CK, and adhering sclerotia in rice plant in RD was 67-78% lower than that in CK. The relative humidity tested significantly lower and light intensity tested significantly higher in RD. The temperature in the early rice growth stages in RD was slightly lower than that in CK, but it was significantly higher （32.3-36.5~C） in the middle stage rice growth stages. The polyphenoloxidase （PPO） activity in RD were lower than that in CK, but the enhanced activity of phenylalanine ammonia-lyase （PAL）, peroxidase （POD） and Chitinase was observed in different stages of rice growth in RD, especially the Chitinase which showed higher activity in all investigating days.

关键词： rice sheath blight integrated rice-duck system sclerotia microclimate protective enzyme

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Nickel-Catalyzed Difluoromethylation of Arylboronic Acids with Bromodifluoromethane

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Chinese Journal of Chemistry 2018年第2期36卷 143-146页

作者： Xia-Ping Fu Yu-lan xiao Xingang zhang Key Laboratory of Organofluorine Chemistry Center for Excellence in Molecular Synthesis Shanghai Institute of Organic Chemistry Chinese Academy of Sciences 345 Lingling Road Shanghai 200032 China

Although bromodifluoromethane （BrCF2H） is a simple and readily available fluorine source, direct formation of difluoromethylated arenes with BrCF2H has not been reported. Herein, we describe an efficient method to access difluoromethylated arenes through a nickel-catalyzed difluoromethylation of arylboronic acids with BrCF2H. The reaction exhibits high efficiency, good functional group tolerance and broad substrate scope, thus providing an efficient route for applications in drug discovery and development. Preliminary mechanistic studies reveal that a difluoromethyl radical is involved in the reaction.

关键词： arylboronic acids bromodifluoromethane cross-coupling difluoromethylation nickel

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Neuroprotective effects of naturally sourced bioactive polysaccharides: an update

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Neural Regeneration Research 2022年第9期17卷 1907-1912页

作者： xiao-lan Xu Song Li Rong zhang Wei-Dong Le Department of Neurology Sichuan Academy of Medical Sciences-Sichuan Provincial People’s HospitalUniversity of Electronic Science and Technology of ChinaChengduSichuan ProvinceChina Liaoning Provincial Center for Clinical Research on Neurological Diseases The First Affiliated Hospital of Dalian Medical UniversityDalianLiaoning ProvinceChina

Polysaccharides are macromolecular complexes that have various biological *** vivo and in vitro studies have shown that polysaccharides play neuroprotective roles through multiple mechanisms;consequently,they have potential in the prevention and treatment of neurodegenerative *** paper summarizes related research published during 2015-2020 and reviews advances in the understanding of the neuroprotective effects of bioactive *** review focuses on 15 bioactive polysaccharides from plants and fungi that have neuroprotective properties against oxidative stress,apoptosis,neuroinflammation,and excitatory amino acid toxicity mainly through the regulation of nuclear factor kappa-B,phosphatidylinositol-3-kinase/protein kinase B,mitogen-activated protein kinase,nuclear factor-E2-related factor 2/hemeoxygenase-1,c-jun N-terminal kinase,protein kinase B-mammalian target of rapamycin,and reactive oxygen species-nucleotide-binding oligomerization domain,leucine-rich repeat and pyrin domain-containing 3 signaling *** bioactive polysaccharides have potential in the prevention and treatment of neurodegenerative diseases because of their advantageous characteristics,including multi-targeting,low toxicity,and synergistic ***,most of the recent related research has focused on cell and animal *** randomized clinical trials involving large sample sizes are needed to validate the therapeutic benefits of these neuroprotective polysaccharides in patients having neurodegenerative diseases.

关键词： Alzheimer’s disease apoptosis experimental research neurodegeneration neuroinflammation neuroprotective oxidative stress Parkinson’s disease polysaccharides protective mechanisms

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Digital Filter Algorithm Based on Morphological Lifting Scheme and Median Filter

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IEEE/CAA Journal of Automatica Sinica 2018年第5期5卷 1007-1011页

作者： lan zhang the institute of computer information management inner mongolia university of finance and economicsHohhot 010010 China

Abstract--When the circuits in which electronic products are fitted are disturbed by various interrupting signals, wave distortions occur to the normal voltage signals of these circuits. These wave distortions influence the normal operation and life cycle of electronic products. To eliminate the harmful effects of interrupting signals on electronic products, in this paper, a digital filter algorithm based on morphological lifting scheme and median filter （MLS-MF）, which will be used to filter various interrupting signals existing in the circuits in which electronic products are fitted, is proposed. A variety of interrupting sig- nals have been included in simulation studies, and simulation results have demonstrated the effectiveness and feasibility of the proposed digital filter algorithm in high frequency continuous interference, random background noise and damped oscillatory transient interference filter. Index Terms--Digital filter, lifting scheme, median filter, mor- phology.

关键词： Digital filter lifting scheme median filter morphology

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Iron/aluminum nanocomposites prepared by one-step reduction method and their effects on thermal decomposition of AP and AN

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Defence Technology（防务技术） 2023年第4期22卷 74-87页

作者： Yong Kou Yi Wang Jun zhang Kai-ge Guo xiao-lan Song School of Environment and Safety Engineering North University of ChinaTaiyuanShanxi030051China School of Materials Science and Engineering North University of ChinaTaiyuanShanxi030051China School of Ordance Engineering Naval University of EngineeringWuhanHubei430033China School of Chemical Engineering Nanjing University of Science and TechnologyNanjingJiangsu210094China

Aluminum(Al)powder is widely used in solid *** particular,nano-Al has attracted extensive scholarly attention in the field of energetic materials due to its higher reactivity than ***,the existence of aluminum oxide film on its surface reduces the heat release performance of the aluminum powder,which greatly limits its ***,this paper used iron,a component of solid propellant,to coat micron-Al and nano-Al to improve the heat release efficiency and reactivity of Al ***,TEM,EDS,XRD,XPS,and BET were used to investigate the morphological structure and properties of pure Al and Fe/Al composite fuels of different *** results show that Fe was uniformly coated on the surface of Al *** was no reaction between Fe and Al,and Fe/Al composite fuels had a larger specific surface area than pure Al,which could better improve the reactivity of pure ***,the catalytic effects of pure Al and Fe/Al composite fuels of different sizes on ammonium perchlorate and ammonium nitrate were *** results show that the catalysis of pure Al powder could be greatly improved by coating Fe on the surface of Al ***,the micron-Fe/Al composite fuel had a higher catalytic effect than the pure nano-Al ***,Fe/Al composite fuels are expected to be widely used in solid propellants.

关键词： Aluminum Fe/Al composite fuel High reactivity Thermal decomposition AP AN

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3D打印技术在骨盆骨折修复术中的应用价值分析

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中国当代医药 2018年第13期25卷 82-84页

作者：兰小勇张志平叶栋廖学勤南昌大学第三附属医院南昌市第一医院骨科江西南昌330008

目的探讨3D打印技术在骨盆骨折修复术中的应用价值。方法选取2015年1月~2016年5月我院收治的42例骨盆骨折修复患者作为研究对象。采用随机数字表法将其分为对照组、观察组,每组21例。观察组患者在修复术前进行CT扫描断层图像,并应用3D... 详细信息

目的探讨3D打印技术在骨盆骨折修复术中的应用价值。方法选取2015年1月~2016年5月我院收治的42例骨盆骨折修复患者作为研究对象。采用随机数字表法将其分为对照组、观察组,每组21例。观察组患者在修复术前进行CT扫描断层图像,并应用3D技术按与实体1∶1大小打印患者骨盆模型,实行术前评估、规划及修复设计,对照组患者采取常规的骨盆骨折修复方式。分析骨盆骨折修复手术情况,定期复查骨折愈合和复位情况。结果观察组患者的术中出血量及术中输血量显著少于对照组,手术时间短于对照组,差异均有统计学意义(P<0.05)。观察组的术后并发症发生率(0),明显低于对照组(38.10%),差异有统计学意义(χ~2=9.882,P=0.002)。两组患者的复位优良率比较,差异无统计学意义(χ~2=1.273,P=0.259)。结论对于骨盆骨折修复患者进行术前评估、规划及修复,采取3D打印技术可明确骨折移位情况,便于手术的精准操作,有利于缩短手术时间及减少出血量、并发症等,3D打印技术可有效地对骨盆骨折修复术前评估、规划。

关键词：骨盆骨折修复过程 3D打印技术应用价值

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Surface Tension Model Based on Implicit Incompressible Smoothed Particle Hydrodynamics for Fluid Simulation

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Journal of Computer Science & Technology 2017年第6期32卷 1186-1197页

作者： xiao-Kun Wang xiao-Juan Ban Ya-lan zhang Si-Nuo Liu Peng-Fei Ye School of Computer and Communication Engineering University of Science and Technology Beijing Beijing 100083 China Beijing Key Laboratory of Knowledge Engineering for Material Science Beijing 100083 China

In order to capture stable and realistic microscopic features of fluid surface, a surface tension and adhesion method based on implicit incompressible SPH （smoothed particle hydrodynamics） is presented in this paper. It gives a steady and fast tension model and can solve the problem of not considering adhesion. Molecular cohesion and surface minimization are considered for surface tension, and adhesion is added to show the microscopic characteristics of the surface. To simulate surface tension and adhesion stably and efficiently, the surface tension and adhesion model is integrated to an implicit incompressible SPH method. The experimental results show that the method can better simulate surface features in a variety of scenarios compared with previous methods and meanwhile ensure stability and efficiency.

关键词： computer animation fluid simulation implicit incompressible smoothed particle hydrodynamics(IISPH) surface tension

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^(125)Ⅰ示踪研究β-NGF对血脑屏障的通透性

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同位素 2002年第2期15卷 65-68页

作者：朱寿彭韩晓枫张澜生苏州大学核医学院放射毒理室江苏苏州215007

从胎儿脑中提取β-NGF,采用透析和离子交换纤维素层析法分离得到β-NGF提取物,并用SDS-PAGE电泳测得β-NGF相对分子量为13kD,用等电聚焦电泳测得β-NGF等电点分别为9.0、9.2和9.3;通过对PC12细胞培养观察到β-NGF可促进PC12细胞的生长... 详细信息

从胎儿脑中提取β-NGF,采用透析和离子交换纤维素层析法分离得到β-NGF提取物,并用SDS-PAGE电泳测得β-NGF相对分子量为13kD,用等电聚焦电泳测得β-NGF等电点分别为9.0、9.2和9.3;通过对PC12细胞培养观察到β-NGF可促进PC12细胞的生长。动物实验结果表明,静脉注入^(125)I-β-NGF后15min时,有(2.41±0.12)％的摄入量可透过血脑屏障;30min时,进入脑组织中的^(125)I-β-NGF即可增至(4.20±0.07)％。这为开展β-NGF的临床治疗应用提供了科学依据。

关键词： β-NGF 血脑屏障通透性碘125 标记放射性同位素神经生长因子神经系统疾病治疗

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Satellite remote sensing reveals overwhelming recovery of forest from disturbances in Asia

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Atmospheric and Oceanic Science Letters 2025年第1期18卷 46-51页

作者： Yiying Zhu Hesong Wang Anzhi zhang School of Ecology and Nature Conservation Beijing Forestry UniversityBeijingChina Key Laboratory of Regional Climate and Environment for Temperate East Asia Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina College of Forestry and landscape Architecture Xinjiang Agricultural UniversityUrumqiChina

Forest ecosystems play key roles in mitigating human-induced climate change through enhanced carbon uptake;however,frequently occurring climate extremes and human activities have considerably threatened the stability of *** the same time,detailed accounts of disturbances and forest responses are not yet well quantified in *** study employed the Breaks For Additive Seasonal and Trend method-an abrupt-change detection method-to analyze the Enhanced Vegetation Index time series in East Asia,South Asia,and Southeast *** approach allowed us to detect forest disturbance and quantify the resilience after *** showed that 20%of forests experienced disturbance with an increasing trend from 2000 to 2022,and Southeast Asian countries were more severely affected by ***,95%of forests had robust resilience and could recover from disturbance within a few *** resilience of forests suffering from greater magnitude of disturbance tended to be stronger than forests with lower disturbance *** summary,this study investigated the resilience of forests across the low and middle latitudes of Asia over the past two *** authors found that most forests exhibited good resilience after disturbance and about two-thirds had recovered to a better state in *** findings of this study underscore the complex relationship between disturbance and resilience,contributing to comprehension of forest resilience through satellite remote sensing.

关键词： Forest ecosystem Enhanced vegetation index Breaks for additive seasonal and trend method Disturbance Resilience

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