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Assessing the Ecological Quality of Nanjing during Its Urbanization Process by Using Satellite,Meteorological,and Socioeconomic Data

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Journal of Meteorological Research 2020年第2期34卷 280-293页

作者： xin hang Yachun LI Xiaochun LUO Min XU Xiuzhen HAN Jiangsu Climate Center Jiangsu Meteorological BureauNanjing 210008 Jiangsu Meteorological Service Center Jiangsu Meteorological BureauNanjing 210008 National Satellite Meteorological Center China Meteorological AdministrationBeijing 100081

Assessing the ecological status of different districts within a city undergoing urbanization is challenging given their complex surface types and fast pace of *** this study,we utilized satellite data obtained from Landsat5/TM(Thematic Mapper)and Landsat 8/OLI(Operational Land Imager)images in conjunction with meteorological and socioeconomic data to construct a remote sensing ecological index(RSEI)for monitoring the ecological quality of Nanjing,Jiangsu Province.A higher RSEI value corresponded to better ecological *** ratings were associated with RSEI values of city districts:very poor,poor,average,good,and *** Nanjing,the percentage of areas evidencing good RSEI ratings decreased from 55.9%in 2000 to 48.0%in 2018,whereas there was a slight increase in areas with very poor RSEI ratings during this *** the 11 city districts,16.8%,21.8%,and 61.4%respectively evidenced the increasing,decreasing,and stable ecological quality relative to their quality in *** the11 administrative districts in Nanjing,the main urban districts evidenced increased RSEI values in 2018 compared with those in 2000,with the improved areas exceeding the ones that had deteriorated in these ***,the ecological quality of new urban and ed because of the urban expansion,with areas that had deteriorated exceeding the improved *** the three protected ecological zones,the quality of Zijin Mountain National Forest Park was considerably better than that of Laoshan and ***,the urbanization rate and RSEI evidenced a high negative correlation coefficient value(-0.76).The urbanization process of Nanjing induced a declining trend for the ecological quality,indicating the need of strong protection measures for the maintenance or improvement of its ecological environment.

关键词： ecological quality remote sensing ecological index(RSEI) urbanization

Estimation of Chlorophyll-a Concentration in Lake Taihu from Gaofen-1 Wide-Field-of-View Data through a Machine Learning Trained Algorithm

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Journal of Meteorological Research 2022年第1期36卷 208-226页

作者： xin hang Yachun LI xinyi LI Meng XU Liangxiao SUN Jiangsu Climate Center Jiangsu Meteorological BureauNanjing 210008 Nanjing Joint Institute for Atmospheric Sciences Nanjing 210009

Wide-field-of-view(WFV) imager that observes the earth environment with four solar reflective bands in a spatial resolution of 16 m is equipped on board Gaofen-1(GF-1) satellite. Chlorophyll-a(Chl-a) concentration in Lake Taihu, China from 2018 to 2019 is collected and collocated with GF-1 satellite data. This study develops a general and reliable estimation of Chl-a concentration from GF-1 WFV data under turbid inland water conditions. The collocated data are classified according to season and used in random forest(RF) regression to train models for retrieving the lake Chl-a concentration. A composite index is developed to select the most important variables in the models. The models trained for each season show a better performance than the model trained by using the whole year data in terms of the coefficient of determination(R^(2)) between retrievals and observations. Specifically, the R2 values in spring, summer, autumn, and winter are 0.88, 0.88, 0.94, and 0.74, respectively;whereas that using the whole year data is only 0.71. The Chl-a concentration in Lake Taihu exhibits an obvious seasonal change with the highest in summer, followed by autumn and spring, and the lowest in winter. The Chl-a concentration also displays an obvious spatial variation with season. A high concentration occurs mainly in the northwest of the lake. The temporal and spatial changes of Chl-a concentration are almost consistent with the changes in the areas and times of cyanobacteria blooms based on Moderate Resolution Imaging Spectroradiometer(MODIS) data. The proposed algorithm can be operated without a priori knowledge on atmospheric conditions and water quality. Our study also demonstrates that GF-1 data are increasingly valuable for monitoring the Chl-a concentration of inland water bodies in China at a high spatial resolution.

关键词： chlorophyll-a concentration Gaofen-1(GF-1) wide-field-of-view random forest algorithm Lake Taihu

Strontium ferrite powders prepared from oily cold rolling mill sludge by solid-state reaction method

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Rare Metals 2013年第5期32卷 518-523页

作者： Bo Liu Shen-Gen Zang Jian-jun Tian De-an Pan hang-xin Zhu Advanced Material and Technology Institute University ofScience and Technology Beijing

Oily cold rolling mill （CRM） sludge is one of the pollutants emitted by iron and steel plants. Recycling oily CRM sludge can not only reduce pollution but also bring social and environmental benefits. In this study, using oily CRM sludge as sources of iron oxide, the strontium ferrite powders were synthesized in multiple steps including vacuum distillation, magnetic separation, oxidizing roasting, and solidstate reaction. The optimal technological conditions of vacuum distillation and oxidizing roasting were studied carefully. To consider the effects of Fe203/ SrCO3 tool ratio, calcination temperature, milling time and calcination time on magnetic properties of prepared strontium ferrite powders, the orthogonal experimental method was adopted. The maximum saturation magneti- zation （62.6 mA-m2.g-1） of the synthesized strontium ferrite powders was achieved at the Fe203/SrCO3 mol ratio of 6, 5 h milling time, 1250 ~C calcination temperature, and 1 h calcination time. Strontium ferrite powders syn- thesis method not only provides a cheap, high quality raw material for the production of strontium ferrite powders, but also effectively prevents the environmental pollution.

关键词： Strontium ferrite powders Oily cold rolling mill sludge Solid-state reaction method Recycling

Electromagnetic and microwave absorbing properties of FeCoB powder composites

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Rare Metals 2013年第4期32卷 402-407页

作者： Shen-Gen Zhang hang-xin Zhu Jian-Jun Tian De-An Pan Bo Liu Yan-Tao Kang Advanced Material and Technology Institute University of Science and Technology Beijing

The electromagnetic and microwave absorbing properties of FeCoB powder composites prepared by sin- gle-roller melt-spinning and mechanical milling processes were investigated in this paper. The result indicates that the flake-like powders are obtained. As milling time increases, the flake-like powder particles tend to agglomerate, causing the flake-like powders decrease gradually. The milling time plays an important role in the electromagnetic parameters which relates to the shape and size of the powder particles. The calculation shows that the sample milled for 6 h could achieve an optimal reflection loss of -11.5 dB at 5.8 GHz, with mass fraction of 83 % and a matching thickness of 1.8 mm. The result also indicates that the microwave absorbing properties of the FeCoB powder composites are adjustable by changing their thickness, and can be applied as a thinner microwave absorbing material in the range of 2-8 GHz.

关键词： Fe48Co48B4 powder composites Mechanical milling Electromagnetic parameters Microwave absorbing properties

Polycyclic aromatic hydrocarbon in urban soil from Beijing, China

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Journal of Environmental Sciences 2006年第5期18卷 944-950页

作者： LI xing-hong MA Ling-ling LIU Xiu-fen FU Shan CHENG hang-xin XU Xiao-bai State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China Institute of Geophysical and Geochemical Exploration Langfang 065000 China

Polycyclic aromatic hydrocarbons （EPA-PAHs） in the urban surface soils from Beijing were determined using gas chromatography and mass spectrometry （GC-MS）. It is significantly complementary for understanding the PAHs pollution in soil of integrated Beijing city on the basis of the information known in the outskirts. The total concentration of 16 EPA-PAH was from 0.467 to 5.470 μg/g and was described by the contour map. Compound profiles presented that the 4-, 5- and 6-ring PAHs were major compositions. The correlation analysis showed that PAHs have the similar source in the most sampling sites and BaP might be considered as the indicator of PAHs. Characteristic ratios of anthracene （An）/（An＋ phenanthrene （Phe））, fluoranthene （Flu）/（Flu/ pyrene （Pyr）） and benzo[a]pyrene （BaP）/laenzo[g,h,i]perylene （BghiP） indicated that the PAHs pollutants probably mainly originated from the coal combustion and it was not negligible from vehicular emission. The level of PAHs in our study area was compared with other studies.

关键词： PAHs urban soil source Beijing

Design and performance test of the fast-steering mirror with flexure hinge used in vehicle track-launch system

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Optoelectronics Letters 2019年第3期15卷 179-184页

作者： XU xin-hang Zhang Gui-ming CHEN Chang-bo Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of SciencesChangchun130033China Xuchang College of Vocational Technology Xuchang461000China University of Chinese Academy of Science Beijing100049China

To accurately launch laser, a fast-steering mirror(FSM) with flexure hinge is designed. First, actuators, angle sensors and flexure hinge were designed or selected respectively according to requirements of vehicle track-launch system. Then, the servo control system with two closed loops was projected after fine manufacturing and assembling. Finally, the pointing precisions of FSM on the static and vibrancy platforms were tested. The results show that the designed FSM with pointing error range on the static platform is less than 0.9″, and less than 44.5″ on the vibrancy shaker, which can meet the requirements of vehicle track-launch system application.

关键词： Design performance

Synthesis,Crystal Structure and Luminescence of a New Zn(Ⅱ) Complex [Zn(1,2,3-HBTC)(L)]_2 Constructed by Mixed Ligands

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Chinese Journal of Structural Chemistry 2015年第5期34卷 725-728页

作者： WANG Xiu-Yan ZHAO Zhong-Yu LIU Rui XU Ye LI xin-hang XU Zhan-Lin Key Laboratory of Preparation and Applications of Environmental Friendly Materials Jilin Normal University Department of Chemistry Jilin Normal University

A new Zn（Ⅱ） complex,[Zn（1,2,3-HBTC）（L）]2（1,L = 2-（2-chloro-6-fluorophenyl）-1H-imidazo[4,5-f][1,10]phenanthroline and 1,2,3-H3 BTC = 1,2,3-benzentricarboxylic acid）,was synthesized under hydrothermal conditions and characterized by single-crystal X-ray *** crystallizes in triclinic,space group P1 with a = 10.455（2）,b = 11.533（2）,c = 12.499（3） A,α = 116.97（3）,β = 94.08（3）,γ = 103.29（3）o,V = 1280.2（4） A^3,Z = 1,C56H28Cl2F2N8O12Zn2,Mr = 1244.50,Dc = 1.614 g/cm^3,F（000） = 628,μ（Mo Ka） = 1.124 mm^-1,R = 0.0502 and w R = *** compound 1,two 1,2,3-HBTC anions bridge two Zn（Ⅱ） atoms to give a dimeric structure with Zn···Zn distance of 3.15 *** dimers interact through π-π stackings between two L ligands to result in a supramolecular ***,N–H···O and O–H···N hydrogen bonds further stabilize the 2D supramolecular architecture of *** addition,the luminescent property of 1 has been studied.

关键词： hydrogen bonds crystal structure dimer 1 2 3-benzentricarboxylic acid

General anesthetic agents induce neurotoxicity through oligodendrocytes in the developing brain

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Zoological Research 2024年第3期45卷 691-703页

作者： Wen-xin hang Yan-Chang Yang Yu-Han Hu Fu-Quan Fang Lang Wang xing-Hua Qian Patrick M.McQuillan Hui Xiong Jian-hang Leng Zhi-Yong Hu Department of Anesthesiology First Affiliated HospitalZhejiang University School of MedicineHangzhouZhejiang 310003China Department of Cell Biology Yale UniversityNew HavenCT 06520USA Department of Neurology of the First Affiliated Hospital Interdisciplinary Institute of Neuroscience and TechnologySchool of Brain Science and Brain MedicineZhejiang University School of MedicineHangzhouZhejiang 310027China Department of Anesthesiology Jiaxing Maternity and Childcare Health HospitalJiaxingZhejiang 314009China Department of Anesthesiology Penn State Hershey Medical CentrePenn State College of MedicineHersheyPA 17033USA Department of Central Laboratory Affiliated Hangzhou First People’s HospitalWestlake University School of MedicineHangzhouZhejiang 310006China

General anesthetic agents can impact brain function through interactions with neurons and their effects on glial *** perform essential roles in the central nervous system,including myelin sheath formation,axonal metabolism,and neuroplasticity *** are particularly vulnerable to the effects of general anesthetic agents resulting in impaired proliferation,differentiation,and *** are increasingly interested in the effects of general anesthetic agents on *** agents not only act on the surface receptors of oligodendrocytes to elicit neuroinflammation through modulation of signaling pathways,but also disrupt metabolic processes and alter the expression of genes involved in oligodendrocyte development and *** this review,we summarize the effects of general anesthetic agents on *** anticipate that future research will continue to explore these effects and develop strategies to decrease the incidence of adverse reactions associated with the use of general anesthetic agents.

关键词： Oligodendrocytes General anesthetic agents Neurotoxicity Central nervous system Perioperative neurocognitive disorders

Crystal Structure and Luminescence of a New Two-dimensional Sr(Ⅱ) Coordination Polymer Based on 3,5-Dinitro-salicylic Acid and 1,10-Phenanthroline

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Chinese Journal of Structural Chemistry 2015年第8期34卷 1295-1299页

作者： KONG Zhi-Guo GUO Sheng-Nan HE Gui-Yuan LI xin-hang JIAO Yu-Qi WANG Xiu-Yan Key Laboratory of Preparation and Applications of Environmental Friendly Materials Jilin Normal University Department of Chemistry Jilin Normal University

In this work, we report a new two-dimensional Sr（II） coordination polymer, namely, [Sr（L）（phen）（H20）] （1）, based on 3,5-dinitro-salicylic acid （H2L） and 1,10-phenanthroline （phen）. It crystallizes in monoclinic, space group P2/1 with a = 15.479（3）, b = 9.4020（19）, c = 13.884（3）/k, β= 103.76（3）°, V= 1962.5（7） A3, Z = 4, C19H12SrN4O8, Mr = 511.95, Dc = 1.733 g/cm^3, F（000） = 1024,μ（MoKa） = 2.805 mm^-1, R = 0.0411 and wR = 0.1069. In 1, each L anion bridges three Sr（II） atoms by using carboxylate and hydroxyl groups, yielding a two-dimensional layer structure. The phen ligands are alternately attached to both sides of the layer. The π-π stacking between L and phen in the same layer and hydrogen-bonding interactions between water molecule and carboxylate oxygen atom play an important role in stabilizing the layer structure of 1. The solid state luminescent property of 1 was also studied at room temperature.

关键词： crystal structure coordination polymer 3,5-dinitro-salicylic acid,