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Effects of seasonal climatic variability on several toxic contaminants in urban lakes: Implications for the impacts of climate change

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Journal of Environmental Sciences 2014年第12期26卷 2369-2378页

作者： Qiong Wu Xinghui Xia xinli mou Baotong Zhu Pujun Zhao Haiyang Dong State Key Laboratory of Water Environment Simulation Key Laboratory of Water and Sediment Sciences of Ministry of EducationSchool of Environment Beijing Normal University School of Chemical and Environmental Engineering Chongqing Three Gorges University

Climate change is supposed to have influences on water quality and ecosystem. However, only few studies have assessed the effect of climate change on environmental toxic contaminants in urban lakes. In this research, response of several toxic contaminants in twelve urban lakes in Beijing, China, to the seasonal variations in climatic factors was studied. Fluorides, volatile phenols, arsenic, selenium, and other water quality parameters were analyzed monthly from2009 to 2012. Multivariate statistical methods including principle component analysis, cluster analysis, and multiple regression analysis were performed to study the relationship between contaminants and climatic factors including temperature, precipitation, wind speed, and sunshine duration. Fluoride and arsenic concentrations in most urban lakes exhibited a significant positive correlation with temperature/precipitation, which is mainly caused by rainfall induced diffuse pollution. A negative correlation was observed between volatile phenols and temperature/precipitation, and this could be explained by their enhanced volatilization and biodegradation rates caused by higher temperature. Selenium did not show a significant response to climatic factor variations, which was attributed to low selenium contents in the lakes and soils. Moreover, the response degrees of contaminants to climatic variations differ among lakes with different contamination levels. On average, temperature/precipitation contributed to 8%, 15%, and 12% of the variations in volatile phenols, arsenic, and fluorides,respectively. Beijing is undergoing increased temperature and heavy rainfall frequency during the past five decades. This study suggests that water quality related to fluoride and arsenic concentrations of most urban lakes in Beijing is becoming worse under this climate change trend.

关键词： Climatic variations Urban lakes Volatile phenols Arsenic Fluorides Selenium Water quality

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Changes in Climatic Factors Influencing the Growth Period of Corn in Fengjie County

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Asian Agricultural Research 2014年第12期6卷 82-84页

作者： Xiaozhen MAO xinli mou Chen MA Jiang HUANG Lin YUAN Key Laboratory of Water Environment Evolution and Pollution Control in Three Gorges Reservoir Chongqing Three Georges University

Under the background of global climate change,we analyze the change tendency of average temperature and amount of precipitation influencing the corn's growth period. The results show that from March to August,the monthly temperatures show an upward trend,but the rise is different in different months,and the maximum temperature rise is in May. Precipitation in different months has different trends. Climate change brings about favorable conditions at high altitudes in Fengjie,reduces production due to the temperature drop after the beginning of autumn,and increases the pressure on the corn supply.

关键词： Fengjie Corn Growth period Temperature Precipitati

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Evaluation of the Agricultural Non-point Source Pollution in Chongqing Based on PSR Model

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Asian Agricultural Research 2014年第9期6卷 69-71,77页

作者： Hanwen ZHANG xinli mou Hui XIE Hong LU Xingyun YAN Key Laboratory of Water Environment Evolution and Pollution Control in Three Gorges Reservoir Chongqing Three Georges University School of Finance and Economics Chongqing Three Georges University

Through a series of exploration based on PSR framework model,for the purpose of building a suitable Chongqing agricultural nonpoint source pollution evaluation index system model framework,combined with the presence of Chongqing specific agro-environmental issues,we build a agricultural non-point source pollution assessment index system,and then study the agricultural system pressure,agro-environmental status and human response in total 3 major categories,develope an agricultural non-point source pollution evaluation index consisting of 3 criteria indicators and 19 indicators. As can be seen from the analysis,pressures and responses tend to increase and decrease linearly,state and complex have large fluctuations,and their fluctuations are similar mainly due to the elimination of pressures and impact,increasing the impact for agricultural non-point source pollution.

关键词： PSR model Agricultural non-point source pollution

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Effects of Rainfall Change on Agricultural Non-point Source Pollution in Liangping County

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Meteorological and Environmental Research 2013年第10期4卷 41-44页

作者： Hui Xie Yuling Wang Hanwen Zhang xinli mou Nian Zhou College of Chemistry & Environmental Engineering Chongqing Three Gorges University

[Objective] The study aimed to discuss the impact of rainfall change on agricultural non-point source pollution in Uangping County. E Method ] Based on daily precipitation data of Liangping from 1955 to 2011, changes of precipitation and frequency of heavy rain in Uangping during a year were analyzed firstly, and then the risk of surface runoff caused by rainfall to agricultural non-point source pollution was studied, finally chan- ging trends of annual average precipitation and frequency during 1955 -2011 were discussed using Mann-Kendal method. [ Result] Total precipitati- on of heavy rain in Liangping mainly concentrated from late May to early September, especially in eady and middle July as well as early September. Meanwhile, fertilizer and pesticide were applied to main crops in Liangping in the periods above, so agricultural non-point source pollution became more serious. In recent 57 years, annual average precipitation and frequency of heavy rain in Liangping showed an increasing trend respectively, and surface runoff rose with the increase of the precipitation, thereby probably enlarging agricultural pollution area. [ Conclusion] The research could provide a theoretical basis and technical support for the control of agricultural non-point source pollution.

关键词： Rainfall Heavy rain Agricultural non-point source pollution Mann-Kendall Liangping China

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Ground threat prediction-based path planning of unmanned autonomous helicopter using hybrid enhanced artificial bee colony algorithm

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Defence Technology（防务技术） 2024年第2期32卷 1-22页

作者： Zengliang Han mou Chen Haojie Zhu Qingxian Wu School of Automation Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211106China

Unmanned autonomous helicopter(UAH)path planning problem is an important component of the UAH mission planning system.Aiming to reduce the influence of non-complete ground threat information on UAH path planning,a ground threat prediction-based path planning method is proposed based on artificial bee colony(ABC)algorithm by collaborative thinking strategy.Firstly,a dynamic threat distribution probability model is developed based on the characteristics of typical ground threats.The dynamic no-fly zone of the UAH is simulated and established by calculating the distribution probability of ground threats in real time.Then,a dynamic path planning method for UAH is designed in complex environment based on the real-time prediction of ground threats.By adding the collision warning mechanism to the path planning model,the flight path could be dynamically adjusted according to changing no-fly zones.Furthermore,a hybrid enhanced ABC algorithm is proposed based on collaborative thinking strategy.The proposed algorithm applies the leader-member thinking mechanism to guide the direction of population evolution,and reduces the negative impact of local optimal solutions caused by collaborative learning update strategy,which makes the optimization performance of ABC algorithm more controllable and efficient.Finally,simulation results verify the feasibility and effectiveness of the proposed ground threat prediction path planning method.

关键词： UAH Path planning Ground threat prediction Hybrid enhanced Collaborative thinking

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Spin logic devices based on negative differential resistance -enhanced anomalous Hall effect

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International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1437-1448页

作者： Hongming mou Ziyao Lu Yuchen Pu Zhaochu Luo Xiaozhong Zhang Key Laboratory of Advanced Materials(MOE) School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China State Key Laboratory of Artificial Microstructure and Mesoscopic Physics School of PhysicsPeking UniversityBeijing 100871China

Owing to rapid developments in spintronics,spin-based logic devices have emerged as promising tools for next-generation computing technologies.This paper provides a comprehensive review of recent advancements in spin logic devices,particularly focusing on fundamental device concepts rooted in nanomagnets,magnetoresistive random access memory,spin–orbit torques,electric-field modu-lation,and magnetic domain walls.The operation principles of these devices are comprehensively analyzed,and recent progress in spin logic devices based on negative differential resistance-enhanced anomalous Hall effect is summarized.These devices exhibit reconfigur-able logic capabilities and integrate nonvolatile data storage and computing functionalities.For current-driven spin logic devices,negative differential resistance elements are employed to nonlinearly enhance anomalous Hall effect signals from magnetic bits,enabling reconfig-urable Boolean logic operations.Besides,voltage-driven spin logic devices employ another type of negative differential resistance ele-ment to achieve logic functionalities with excellent cascading ability.By cascading several elementary logic gates,the logic circuit of a full adder can be obtained,and the potential of voltage-driven spin logic devices for implementing complex logic functions can be veri-fied.This review contributes to the understanding of the evolving landscape of spin logic devices and underscores the promising pro-spects they offer for the future of emerging computing schemes.

关键词： spin logic spin–orbit torque negative differential resistance full-adder

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Preparation and Characterization of pH-Responsive Charge Reversal Nanocomposite for miRNA Delivery

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Journal of Wuhan University of Technology(Materials Science) 2024年第4期39卷 1048-1052页

作者：余丹 YE Liyuan LI Binbin mou Fangzhi 殷义霞 State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China Hainan Institute Wuhan University of TechnologySanya 572000China Biomedical Materials and Engineering Research Center of Hubei Province Wuhan University of TechnologyWuhan 430070China

pH-responsive charge reversal loaded miRNA nanocomposite was prepared by electrostatic self-assembly.The morphology,particle size and zeta potential of the nanocomposites were analyzed by transmission electron microscopy and dynamic light scattering.The synthesis of the polymer was analyzed by^(1)H-NMR.The zeta-potential changes and cellular uptake effects of the nanocomplexes under different pH environments were investigated.The experimental results show that the surface morphology of the nanocomposite is spherical,and the average particle size is about 135 nm.As the pH value of the solution gradually decreases,the surface charge of the nanocomposite reverses from negative charge to positive charge(from-9.4 to+17.1 mV).Cellular uptake mediated by pH-responsive nanocomposite is selective for tumor cells,and the cellular uptake effect in tumor cells at pH 6.5 was approximately 3 times higher than that at pH 7.4.This pH responsive charge reversal nanocomposite has promising application prospects for gene delivery in the weak acid environment of tumors.

关键词： charge conversion siRNA delivery pH responsive cancer therapy

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Type one autoimmune pancreatitis based on clinical diagnosis: A case report

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World Journal of Clinical Cases 2024年第14期12卷 2438-2444页

作者： Bi-Yu Zhang mou-Wang Liang Shuang-Xi Zhang Department of Gastroenterology Guangzhou University of Chinese Medicine Shunde HospitalFoshan 528300Guangdong ProvinceChina Department of Gastroenterology Guangzhou University of Chinese MedicineGuangzhou 510006Guangdong ProvinceChina

BACKGROUND Autoimmune pancreatitis(AIP)is a rare form of autoimmune-mediated pancrea-titis,which is easily misdiagnosed as pancreatic cancer and thus treated surgi-cally.We studied the diagnosis and treatment of a patient with type 1 AIP recent-ly admitted to our hospital,and reviewed the literature to provide a reference for clinical diagnosis of AIP.CASE SUMMARY The chief complaint was yellowing of the body,eyes and urine for 21 d.The pa-tient's clinical presentation was obstructive jaundice and imaging suggested pan-creatic swelling.It was difficult to distinguish between inflammation and tumor.Serum immunoglobulin G4(IgG4)was markedly elevated.IgG4 is an important serological marker for type 1 AIP.The patient was diagnosed with AIP,IgG4-related cholangitis,acute cholecystitis and hepatic impairment.After applying hormonal therapy,the patient's symptoms improved significantly.At the same time,imaging suggested that pancreatic swelling subsided,and liver function and other biochemical indicators decreased.The treatment was effective.CONCLUSION In patients with pancreatic swelling,the possibility of AIP should be considered.

关键词： Autoimmune pancreatitis Characteristics Diagnosis Immunoglobulin G4 Case report

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Synthesis of uniform two-dimensional MoS_(2) films via thermal evaporation

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Nano Research 2024年第4期17卷 3217-3223页

作者： Xue-Wei Lu Zhewei Li Chen-Kai Yang Weijia mou Liying Jiao Key Laboratory of Organic Optoelectronics and Molecular Engineering of the Ministry of Education Department of ChemistryTsinghua UniversityBeijing 100084China

Two-dimensional(2D)molybdenum disulfide(MoS_(2))holds great potential for various applications such as electronic devices,catalysis,lubrication,anti-corrosion and so on.Thermal evaporation is a versatile thin film deposition technique,however,the conventional thermal evaporation techniques face challenges in producing uniform thin films of MoS_(2) due to its high melting temperature of 1375℃.As a result,only thick and rough MoS_(2) films can be obtained using these methods.To address this issue,we have designed a vacuum thermal evaporation system specifically for large-scale preparation of MoS_(2) thin films.By using K2MoS4 as the precursor,we achieved reliable deposition of uniform polycrystalline MoS_(2) thin films with a size of 50 mm×50 mm and controllable thickness ranging from 0.8 to 2.4 nm.This approach also allows for patterned deposition of MoS_(2) using shadow masks and sequential deposition of MoS_(2) and tungsten disulfide(WS_(2)),similar to conventional thermal evaporation techniques.Moreover,we have demonstrated the potential applications of the obtained MoS_(2) thin films in field effect transistors(FETs),memristors and electrocatalysts for hydrogen evolution reaction(HER).

关键词： thermal evaporation molybdenum disulfide two-dimensional memristors hydrogen evolution reaction

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Geochemistry, zircon U–Pb geochronology, and Hf isotopes of S-type granite in the Baoshan block, constraints on the age and evolution of the Proto-Tethys

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Acta Geochimica 2024年第1期43卷 40-58页

作者： Jianjun Zhang Chuanlong mou Chendong Liu Yong Zhang Ting Chen Hualiang Li Institute of Geological Survey East China University of TechnologyNanchang 330013China School of Earth Sciences East China University of TechnologyNanchang 330013China Chengdu Geological Survey Center Chengdu 610081China School of Water Resources&Environmental Engineering East China University of TechnologyNanchang 330013China

Geochemistry, zircon U–Pb geochronology, and Hf isotope data for the Early Paleozoic granites in the Baoshan Block reveal the Early Paleozoic tectonic evolution of the Proto-Tethys. The samples are high-K, calcalkaline, strongly peraluminous rocks with A/CNK values of 1.37–1.46, are enriched in SiO2, K2O, and Rb, and are depleted in Nb, P, Ti, Eu, and heavy rare earth elements,which indicates the crystallization fractionation of the granitic magma. Zircon U–Pb dating indicates that they formed in ca. 480 Ma. The Nansa granites have εHf(t) values ranging from-16.04 to 4.36 with corresponding TC DMages of 2.10–0.81 Ga, which suggests the magmas derived from the partial melting of ancient metasedimentary with minor involvement of mantle-derived components. A synthesis of data for the Early Paleozoic igneous rocks in the Baoshan block and adjacent(Tengchong,Qiangtang, Sibumasu, Himalaya, etc.) blocks indicates that these blocks were all aligned along the proto-Tethyan margin of East Gondwana in the Early Paleozoic. The Early Paleozoic S-type granites from Nansa were generated in a high-temperature and low-pressure(HTLP) extensional tectonic setting, which resulted from Andean-type orogeny instead of the final assembly of Gondwana or crustal extension in a non-arc environment. In certain places, an expanding environment may exist in opposition to the tectonic backdrop of the lithosphere’s thickening and shortening, leading the crust to melt and decompress,mantle-derived materials to mix, and a small quantity of peraluminous granite to emerge.

关键词： Baoshan block Early Paleozoic Granite Geochemistry Zircon Geochronology Hf isotope

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