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Chemical compositions of precipitation and scavenging of particles in Beijing

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Science China Chemistry 2005年第3期48卷 265-272页

作者： HU Min zhang jing wu Zhijun State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences Peking University Beijing 100871 China State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences Peking University Beijing 100871 China State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences Peking University Beijing 100871 China

Totally 23 precipitation samples were collected in Beijing from May to November in 2003. In order to investigate the chemical composition of precipitation samples, pH, conductivity, concentrations of water-soluble ions and organic acids were analyzed. The average pH of pre-cipitations is 6.18, belonging to the neutral range; the average conductivity is 52.23 μS/cm, which indicates that precipitations in Beijing are obviously polluted; SO 24? , NO3 ? are the most abundant anions with the average concentrations of 521 and 174 μeq·L?1, respectively; the average 2SO 4? /NO3? equivalent ratio is 3.1, which decreases by about 15% compared with the result of 1994; NH+ 4 and Ca2+ are the most abundant cations with the average concentrations of 376 and 397 μeq·L?1, respectively; formic acid, acetic acid and oxalic acid are the main organic acids with the average concentrations of 4.62, 4.60 and 1.17 μeq·L?1, respectively, accounting for 2% of the overall anions. Obvious differences between concentrations before and after precipitation are also observed by SJAC (Steam Jet Aerosol Collector), which shows the removal of particles from the atmosphere by precipitation.

关键词： precipitation, particles, ions, organic acids, scavenging.

液质联用法结合自动固相萃取同时测定药食同源杂粮中14种真菌毒素

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粮食与油脂 2024年第8期37卷 146-150页

作者：黄忠亮王海波廖强李琬婧吴张静覃弘毅广西壮族自治区医疗器械检测中心广西南宁530031 广西-东盟食品检验检测中心广西南宁530029 广西壮族自治区食品药品审评查验中心广西南宁530029 南宁市食品药品检验所广西南宁530000

建立液相色谱-串联质谱法结合自动固相萃取同时测定药食同源杂粮中14种真菌毒素的方法。样品经乙腈-水溶液(体积比6:4)提取,再利用一步法快速净化柱(QMyco-Multi)在自动固相萃取仪上完成快速净化,最后通过液相色谱分离,在电喷雾离子源(E... 详细信息

建立液相色谱-串联质谱法结合自动固相萃取同时测定药食同源杂粮中14种真菌毒素的方法。样品经乙腈-水溶液(体积比6:4)提取,再利用一步法快速净化柱(QMyco-Multi)在自动固相萃取仪上完成快速净化,最后通过液相色谱分离,在电喷雾离子源(ESI)正负离子模式下同时进行多重反应离子监测(MRM)。结果表明:14种真菌毒素在不同质量浓度范围内线性关系良好(相关系数>0.99),定量限为0.2~10.0μg/kg,加标回收率为81%~117%,相对标准偏差(RSD)为2.0%~7.2%(n=6)。制备的方法简单快速、灵敏准确,可用于药食同源杂粮中14种真菌毒素的同时测定。

关键词：药食同源杂粮真菌毒素一步法快速净化自动固相萃取

Quantum Properties of Two-Mode Squeezed Even and Odd Coherent States

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Communications in Theoretical Physics 2007年第2期47卷 317-324页

作者： zhang jing wu Wei MENG Shao-Ying Department of Physics Laboratory of Atoms and Radiation Liaoning University Shenyang 110036 China

Two new types of quantum states are constructed by applying the operator s（ξ） = exp（ξ＊ ab - ξa＋b＋） on the two-mode even and odd coherent states. The mathematical and quantum statistical properties of such states are investigated. Various nonclassical features of these states, such as squeezing properties, the inter-mode photon bunching, and the violation of Cauchy-Schwarz inequality, are discussed. The Wigner function in these states are studied in detail.

关键词： two-mode squeezed even/odd coherent states quantum statistical properties

Separation of contact stress components by moire interferometry

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Acta Mechanica Sinica 2007年第6期23卷 707-711页

作者： Ming Li Jue zhang Chong wu jing Fang College of Engineering Peking University Beijing 100871 China

A hybrid technique of combining moire measurement and analytical solution is developed to separate the normal and the tangential components of distributed contact stresses between two co-plane bodies. The moire interfe-rometry offers the displacement fields near the deformed contact zone, from which the tangential strains and boundary slopes of the deformed configurations can be evaluated. Those experimental results provide boundary conditions for the discrete integration of Flamant＇s solutions, to inversely compute the separated components of the contact stresses.

关键词： Moire patterns Contact deformation Experimental/analytical hybrid solution

Edaravone rescues the lung by inhibiting lipid peroxidation and pro-inflammatory cytokines in a rat model

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Chinese Medical Journal 2014年第5期127卷 968-970页

作者： wu Zhouyang Ming Yu zhang Zhao wu jing wu Zhilin Yao Shanglong Department of Anesthesia and Critical Care Union Hospital Tongji Medical College Huazhong University of Science and TechnologyWuhan Hubei 430022 China

Acute lung injury/acute respiratory distress syndrome （ALI/ARDS） is a frequent complication in critically ill patients and cause significant mortality.1 Effects of reactive oxygen species （ROS） on alveolar epithelial cells are involved in the pathophysiology of ALI/*** can provoke DNA damage,lipid peroxidation,and activation of various genes coding for proteins involved in inflammation and cell damage.

关键词： acute lung injury edaravone free radical scavenger inflammation

Crystallization Kinetics of Pr8Fe86-xZrxB6 Amorphous Alloys

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Journal of Iron and Steel Research International 2002年第2期9卷 49-52页

作者： LIU Jian-hua zhang Peng-yue zhang jing-wu LI Hui zhang Xiang-yi Yanshan University

Two experimental methods were adopted to verify the correctness and practicability of the shape meter method: one is to roll aluminum plate, calculate the shape stiffness of mill and rolled piece, and then measure aluminum plate crown to verify shape stiffness equation; the other is to calculate the measured off line data of hot continuous roll and verify the shape mathematical model for measuring and controlling by self adaptation method.

关键词： shape meter method shape stiffness equation mathematical model post calculation self adaptation

Non-alcoholic fatty liver degree and long-term risk of incident inflammatory bowel disease: A large-scale prospective cohort study

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中华医学杂志(英文版) 2024年第14期137卷 1705-1714页

作者： zhang Qian Liu Si wu jing Zhu Shengtao wu Yongdong wu Shanshan zhang Shutian Department of Gastroenterology Beijing Friendship Hospital Capital Medical University National Clinical Research Center for Digestive Disease Beijing Digestive Disease Center Beijing Key Laboratory for Precancerous Lesion of Digestive Disease Beijing China

Background: Non-alcoholic fatty liver disease (NAFLD) and inflammatory bowel disease (IBD) have shown similar worsening epidemic patterns globally and shared various overlapping pathophysiological mechanisms. However, evidence on the relationship between NAFLD and IBD risk is lacking. We aimed to investigate the associations between long-term risk of incident IBD and NAFLD in a large prospective ***: Participants from the United Kingdom Biobank cohort (https://***/) who were free of IBD and alcoholic liver disease at baseline were enrolled. Baseline non-alcoholic fatty liver degree was measured by the well-established fatty liver index (FLI). The outcomes of interest included incident IBD, ulcerative colitis (UC), and Crohn’s disease (CD). Multivariable Cox proportional hazard regression was used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs).Results: Among 418,721 participants (mean FLI: 48.11 ± 30.11), 160,807 (38.40%) participants were diagnosed as NAFLD at baseline. During a median of 12.4 years’ follow-up, 2346 incident IBD cases (1545 UC, 653 CD, and 148 IBD-unclassified) were identified. Due to limited events, those IBD-unclassified were combined in UC or CD when examining the associated risk of UC or CD, separately. Compared with the lowest quartile of FLI, the highest quartile showed a separately 36.00%, 25.00%, and 58.00% higher risk of incident IBD (HRQ4vs. Q1 =1.36, 95% CI: 1.19-1.55,Ptrend <0.001), UC (HRQ4vs. Q1 =1.25, 95% CI: 1.07-1.46,Ptrend=0.047), and CD (HRQ4vs. Q1 =1.58, 95% CI: 1.26-1.97,Ptrend <0.001) after multivariable adjustment. Compared with non-NAFLD, NAFLD participants had a significantly higher risk of incident IBD (HR=1.13, 95% CI: 1.04-1.24) and CD (HR =1.36, 95% CI: 1.17-1.58).Conclusions: Higher degree of non-alcoholic fatty liver is associated with increased risk of incident IBD. Interventions aimed at improving NAFLD may be a potential targeted strategy for the detection and treatm

关键词： Non-alcoholic fatty liver disease Inflammatory bowel disease Ulcerative colitis Crohn’s disease Cohort study

Targeting synaptic pathology in Alzheimer’s disease

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Zoological Research 2024年第4期45卷 875-876页

作者： jing Cao Yun-wu zhang Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research Institute of NeuroscienceSchool of MedicineXiamen UniversityXiamenFujian 361102China

Alzheimer’s disease(AD)is a neurodegenerative disorder characterized by memory and cognitive *** two primary pathological hallmarks of AD include the accumulation ofβ-amyloid(Aβ)plaques and formation of neurofibrillary tangles(NFTs)composed predominantly of hyperphosphorylated tau protein(zhang et al.,2023).Moreover,synaptic dysfunction is considered another crucial factor in AD pathogenesis and is closely associated with cognitive ***,synaptic damage,loss,and dysfunction manifest earlier than the pathological features of Aβplaques and NFTs(Knopman et al.,2021).Therefore,understanding the mechanisms underlying synaptic dysfunction in AD is vital for providing insights into disease mechanisms and developing novel therapeutic strategies.

关键词： Alzheimer Aβ tau

Adaptive Graph Convolutional Adjacency Matrix Network for Video Summarization

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Computers, Materials & Continua 2024年第8期80卷 1947-1965页

作者： jing zhang Guangli wu Shanshan Song School of Cyberspace Security Gansu University of Political Science and LawLanzhou730000China

Video summarization aims to select key frames or key shots to create summaries for fast retrieval,compression,and efficient browsing of *** neural networks efficiently capture information about graph nodes and their neighbors,but ignore the dynamic dependencies between *** address this challenge,we propose an innovative Adaptive Graph Convolutional Adjacency Matrix Network(TAMGCN),leveraging the attention mechanism to dynamically adjust dependencies between graph ***,we first segment shots and extract features of each frame,then compute the representative features of each ***,we utilize the attention mechanism to dynamically adjust the adjacency matrix of the graph convolutional network to better capture the dynamic dependencies between graph ***,we fuse temporal features extracted by Bi-directional Long Short-Term Memory network with structural features extracted by the graph convolutional network to generate high-quality *** experiments are conducted on two benchmark datasets,TVSum and SumMe,yielding F1-scores of 60.8%and 53.2%,*** results demonstrate that our method outperforms most state-of-the-art video summarization techniques.

关键词： Attention mechanism deep learning graph neural network key-shot video summarization