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Sources appointment and health risks of PM_(2.5)-bound trace elements in a coastal city of southeastern China

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Journal of Environmental Sciences 2024年第4期138卷 561-571页

作者： Ziyi Lin Xiaolong Fan Gaojie Chen Youwei hong Mengren Li Lingling Xu Baoye Hu Chen Yang Yanting Chen Zhiqian Shao Jinsheng Chen Center for Excellence in Regional Atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China Key Lab of Urban Environment and Health Institute of Urban EnvironmentChinese Academy ofSciencesXiamen 361021China university of Chinese Academy of Sciences Beijing 100049China Minnan Normal university Zhangzhou 363000China

To gain a comprehensive understanding of sources and health risks of trace elements in an area of China with high population densities and low PM_(2.5)concentrations,15 trace elements(Al,K,Ca,Ti,V,Cr,Mn,Fe,Ni,Cu,Zn,As,Sn,Ba,Pb)in PM_(2.5)were monitored from December 2.2. to November 2.2. in a representative city,*** concentrations of trace elements in Xiamen displayed an obvious seasonal variation and were dominated by K,Fe,Al,Ca and *** on Positive Matrix Factorization analysis,source appointment revealed that the major sources of trace elements in Xiamen were traffic,dust,biomass and firework combustion,industrial manufacture and shipping *** to health risk assessment combined with the source appointment results,it indicated that the average noncarcinogenic risk was below the threshold and cancer risk of four hazardous metals(Cr,Ni,As,Pb)exceeded the threshold(10^(-6)).Traffic-related source had almost half amount of contribution to the health risk induced by PM_(2.5)-bound trace *** the dust transport period or Spring Festival period,the health risks exceeded an acceptable threshold even an order of magnitude higher,suggesting that the serious health risks still existed in low PM_(2.5)environment at certain *** risk assessment reminded that the health risk reduction in PM_(2.5)at southeastern China should prioritize traffic-related hazardous trace elements and highlighted the importance of controlling vehicles emissions in the future.

关键词： PM_(2.5)-bound trace elements Seasonal variations Source appointment Health risks Traffic-related source

WHAT DOES CHAOS HAVE TO DO WITH SYSTEMS AND CONTROL ENGINEERING?

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Journal of Systems Science & Complexity 2001年第1期14卷 31-39页

作者： CHEN Guanrong (department of Electrical and Computer Engineering, university of Houston, Houston, Texas 772.4, USA department of Electronic Engineering, city university of hong kong, Kowloon, hong kong SAR, China) university of Houston 美国 77204

Chaos as a very special type of complex dynamical behaviors has been studied for about four decades. Yet the traditional trend of analyzing and understanding chaos has evolved to controlling and utilizing chaos today. Research in the field of chaos modeling, control, and synchronization includes not only ordering chaos, which means to weaken or completely suppress chaos when it is harmful, but also chaotification, which refers to enhancing existing Chaos or creating chaos purposely when it is useful, by any means of control technology. This article offers a brief overview about the potential impact of controlled chaos on beneficial applications in science and engineering, and introduces some recent progress in chaotification via feedback control methods.

关键词： Chaos chaos control chaotification complexity feedback.

Dual effect of cobra cardiotoxin on vascular smooth muscle and endothelium

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Acta Pharmacologica Sinica 1998年第3期 2-7页

作者： Heung HO, Chiu Yin HUANG Shou Jian 2. Jean Pierre BOURREAU 3 ( department of Physiology, The university of {2., 5 Sassoon Road, {2., China )

目的：探讨眼镜蛇毒的心脏毒素对大鼠主动脉的毒性反应．方法：以内皮完整和去内皮后的主动脉环的收缩反应为检测指标．结果：心脏毒素（ＣＴＸ）１０μｍｏｌ·Ｌ－１致使去内皮后的血管环产生短暂舒张反应及紧接着的持续收缩反应．去... 详细信息

目的：探讨眼镜蛇毒的心脏毒素对大鼠主动脉的毒性反应．方法：以内皮完整和去内皮后的主动脉环的收缩反应为检测指标．结果：心脏毒素（ＣＴＸ）１０μｍｏｌ·Ｌ－１致使去内皮后的血管环产生短暂舒张反应及紧接着的持续收缩反应．去内皮或加入一氧化氮（ＮＯ）合成酶抑制剂ＬＮＡＭＥ，虽能防止ＣＴＸ引起的舒张却不影响随后的收缩．ＣＴＸ本身虽会引起血管环的收缩，却又能量效性地抑制苯福林及高钾激素的收缩幅度，ＣＴＸ引起的收缩有强烈的外钙依赖性．钙浓度１ｍｍｏｌ·Ｌ－１产生最高效应然后随钙浓度增加而逐减，外钙浓度增至７ｍｍｏｌ·Ｌ－１或先加入钙拮抗剂则可完全抑制ＣＴＸ孕育后乙酰胆碱所引起的短暂舒张．虽有显著减少却能受高钙（５ｍｍｏｌ·Ｌ－１）的保护．结论：ＣＴＸ明显地影响血管收缩功能．首先产生内皮依赖性的短暂舒张反应，随后致使血管平滑肌收缩终致细胞坏死，并使其它激动剂引起的收缩幅度减少．这些现象均与钙协调有密切的关系

关键词：眼镜蛇毒毒素胸主动脉血管平滑肌血管内皮苯福林氯化钾 N~G-硝基精氨酸甲酯钙通道阻滞剂

Gradient analysis of landscape spatial and temporal pattern changes in Beijing metropolitan area

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Science China(Technological Sciences) 2010年第S1期53卷 91-98页

作者： YANG YeTao1,ZHOU QiMing2.GONG JianYa3 & WANG YingYing4 1 Institute of Geophysics and Geomatics,China university of Geosciences,Wuhan 430074,China 2.department of Geography,{2. Baptist university,{2. 3 State Key Laboratory of Information Engineering in Surveying,Mapping and Remote Sensing,Wuhan university,Wuhan 430074,China 4 Hubei Provincial Bureau of Meteorology,Wuhan 430074,China 1. Institute of Geophysics and Geomatics China University of Geosciences Wuhan 430074 China2. Department of Geography Hong Kong Baptist University Hong Kong China3. State Key Laboratory of Information Engineering in Surveying Mapping and Remote Sensing Wuhan University Wuhan 430074 China4. Hubei Provincial Bureau of Meteorology Wuhan 430074 China

The gradient based landscape metrics analysis is now widely used to study the landscape pattern changes in respond to the *** order to discover the trend of spatio-temporal changes in Beijing metropolitan area during the past 15 years,several landscape metrics are computed using a moving window along a 96 km long transect across Beijing metropolitan area from west to ***,the spatial extent of sub-landscape,which is determined by the moving window’s size,is profoundly *** results show that the metrics varies smoothly and regularly along the selected transect when the window size is greater than 6 km×6 km,and irregularly fluctuated for the smaller window size,that the spatial and temporal landscape characteristics of Beijing city match the hypothetical framework of spatio-temporal urban sprawl in the form of alternating processes of diffusion and coalescence well,and that some new trends of the urban sprawl style in Beijing metropolitan area,such as leap-frog manner,are also detected by the gradient landscape analysis.

关键词： gradient analysis landscape metrics spatio-temporal urban expansion multi-extent

A Stable Open-Shell Conjugated Diradical Polymer with Ultra-High Photothermal Conversion Efficiency for NIR-Ⅱ Photo-Immunotherapy of Metastatic Tumor

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Nano-Micro Letters 2024年第2期16卷 1-14页

作者： Yijian Gao Ying Liu Xiliang Li Hui Wang Yuliang Yang Yu Luo Yingpeng Wan Chun‑sing Lee Shengliang Li Xiao‑hong Zhang College of Pharmaceutical Sciences Soochow UniversitySuzhou 215123People’s Republic of China Institute of Functional Nano&Soft Materials(FUNSOM) Soochow UniversitySuzhou 215123People’s Republic of China Center of Super‑Diamond and Advanced Films(COSDAF)&department of Chemistry City University of Hong Kong83 Tat Chee AvenueKowloonHong Kong SARPeople’s Republic of China

Massive efforts have been concentrated on the advance of eminent near-infrared(NIR) photothermal materials(PTMs) in the NIR-Ⅱ window(1000–1700 nm), especially organic PTMs because of their intrinsic biological safety compared with inorganic PTMs. However, so far, only a few NIR-Ⅱresponsive organic PTMs was explored, and their photothermal conversion efficiencies(PCEs) still remain relatively low. Herein, donor–acceptor conjugated diradical polymers with open-shell characteristics are explored for synergistically photothermal immunotherapy of metastatic tumors in the NIR-Ⅱ window. By employing side-chain regulation, the conjugated diradical polymer TTB-2.with obvious NIR-Ⅱ absorption was developed, and its nanoparticles realize a record-breaking PCE of 87.7% upon NIR-Ⅱ light illustration. In vitro and in vivo experiments demonstrate that TTB-2.nanoparticles show good tumor photoablation with navigation of photoacoustic imaging in the NIR-Ⅱ window, without any side-effect. Moreover, by combining with PD-1 antibody,the pulmonary metastasis of breast cancer is high-effectively prevented by the efficient photo-immunity effect. Thus, this study explores superior PTMs for cancer metastasis theranostics in the NIR-Ⅱ window, offering a new horizon in developing radical-characteristic NIR-Ⅱ photothermal materials.

关键词： NIR-Ⅱconjugated polymer Photothermal Radical Nanoparticles Cancer therapy

THE VISCOELASTIC EFFECT ON THE FORMATION OF MESO-GLOBULAR PHASE OF DILUTE HETEROPOLYMER SOLUTIONS

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Chinese Journal of Polymer Science 2003年第2期21卷 117-122页

作者： Chi Wu The Open Laboratory of Bond Selective Chemistry department of Chemical Physics, university of Science and Technology of China, Hefei 2.002. China department of Chemistry The Chinese university of hong kong Shatin, hong kong Univ Sci & Technol China Dept Chem Phys Open Lab Bond Select Chem Anhua 230026 Peoples R China Chinese Univ hong kong Dept Chem Sha Tin Hong Kong Peoples R China

Linear homopolymer chains in poor solvent exist either as individual crumpled single chain globules or asmacroscopic precipitate, depending on whether the solution is in the one- or the two-phase region. However, linearheteropolymer chains in dilute solution might be able to form stable mesoglobules made up of a limited number of chains ifthe degree of amphiphilicity of the chain is sufficiently high and the experimental conditions are appropriate. The self-assembly of block copolymers in a selective solvent is typical of such examples. In practice, the formation of stablemesoglobules can be directly related to the formation of novel polymeric nanopaticles in solution. In this article, we willaddress the formaton of mesoglobular phase not only on the basis of thermodynamics, but also from a kinetic point of view,which leads to the discussion of how viscoelasticity can affect the phase behavior of heteropolymer chains in dilute *** formation and stabilization of several different kinds of novel polymeric nanopedicles will be used to illustrate ourdiscussion.

关键词： Viscoelasticity Mesoglobular phase Heteropolymer Nanoparticle Polymer Dispersion Microphase inversion

Preliminary compact torus injection experiments on the Keda Torus eXperiment reversed field pinch

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Plasma Science and Technology 2024年第10期26卷 56-64页

作者： Tao LAN Chen CHEN Chijin XIAO Weixing DING Jie WU Wenzhe MAO Sen ZHANG Defeng kong Shoubiao ZHANG Zhengwei WU Qilong DONG Yongkang ZHOU Hangqi XU Jiaren WU Zian WEI Xiaohui WEN Hai WANG Chu ZHOU Adi LIU hong LI Jinlin XIE Wandong LIU Ge ZHUANG department of Plasma Physics and Fusion Engineering University of Science and Technology of ChinaHefei 230026People’s Republic of China Plasma Physics Laboratory University of SaskatchewanSaskatoon SK S7N 5E2Canada Institute of Plasma Physics Chinese Academy of SciencesHefei 230031People’s Republic of China

A new compact torus injector(KTX-CTI)has been built for injection experiments on the Keda Torus eXperiment(KTX)reversed field pinch(RFP).The aim is to study the fundamental physics governing the compact torus(CT)central fueling *** experiments conducted under the sole influence of a 0.1 T toroidal magnetic field,the injected CT successfully penetrated the entire toroidal magnetic field,reaching the inner wall of the KTX vacuum *** reaching the inner wall,the CT diffused both radially outward and toroidally within the vessel at a discernible diffusion ***,the inherent helicity within the CT induced a modest KTX plasma current of 2.0 A,consistent with predictions based on helicity *** injection demonstrated the capability to initiate KTX discharges at low loop voltages,suggesting its potential as a pre-ionization and current startup *** RFP discharges featuring CT injection,the central plasma density was found to exceed the Greenwald density limit,with more peaked density profiles,indicating the predominant confinement of CT plasma within the core region of the KTX bulk plasma.

关键词： compact torus fueling reversed field pinch density limit

Hardness Measurement of (TiB_2.TiAl)/TiAl Symmetrically Function Gradient Materials

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Journal of Wuhan university of Technology(Materials Science) 2002年第1期17卷 1-3页

作者：梅炳初 WuhanuniversityofTechnology

( TiB2.TiAl)/TiAl symmetrically function gradient materials ( FGM) were prepared by spark plasma sintering ( SPS). Owing to the difference, of the thermal expansion coefficients between TiB2.and TiAl, a compressive surface stress was introduced to the FGM fry the thermal expansion mismatch. The hardness values of the uniform materials and the FGM were tested, respectively. For the FGM with a compressive surface stress, hardness is obviously superior to that of the uniform material. When the FGM was subjected to heat treatment, the hardness decreased due to a partial relaxation of the compressive surface stress.

关键词： hardness measurement function gradient materials composite

STAGED PROGRESSION MODEL FOR EPIDEMIC SPREAD ON HOMOGENEOUS AND HETEROGENEOUS NETWORKS

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Journal of Systems Science & Complexity 2011年第4期24卷 619-630页

作者： Haifeng ZHANG Michael SMALL Xinchu FU School of Mathematical Sciences Anhui University Hefei 230039 China. department of Electronic and Information Engineering Hong Kong Polytechnic University Hung HornKowloon Hong Kong China. department of mathematics Shanghai University Shanghai 200444 China.

In this paper, epidemic spread with the staged progression model on homogeneous and heterogeneous networks is studied. First, the epidemic threshold of the simple staged progression model is given. Then the staged progression model with birth and death is also considered. The case where infectivity is a nonlinear function of the nodes＇ degree is discussed, too. Finally, the analytical results are verified by numerical simulations.

关键词： Complex network epidemic heterogenous homogeneous the staged progression model.