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Study on the Evaporation Kinetics of Zinc and Lead in Zn-Pb-Bearing Dust Pellets Mixed with Coal Powder

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Journal of Iron and Steel Research International 1999年第1期6卷 12-18页

作者： wang dongyan Chen Weiqing Zhou Rongzhang wang Wenzhong Northeastern University University of Science and Technology Beijing

The study on the evaporation kinetics of zinc and lead in the pellets made of ZnPbbearing dust mixed with carbon ,in nitrogen atmosphere at the temperature range between 1 100 and 1 300 , shows that the reduction temperature has a significant effect on the evaporation rates of zinc and lead and that both the particle size of coal powder and the extra carbon content have no effect on the evaporation rates . The obtained activation energies for the evaporation of zinc and lead are 7942 kJ/mol and 8874kJ/mol respectively. The evaporation rate of zinc is controlled by the reaction between zinc oxide and CO while that of lead is controlled by lead volatilization and the diffusion of gaseous lead through gas boundary layer covering the surface of liquid lead.

关键词： ZnPbbearing dust pellets mixed with coal powder evaporation kinetics

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Optimization of Rural Settlement Distributions Based On the Ecological Security Pattern: A Case Study of Da’an City in Jilin Province of China

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Chinese Geographical Science 2020年第5期30卷 824-838页

作者： YIN Jingbo LI Hong wang dongyan LIU Shuhan College of Earth Science Jilin UniversityChangchun 130061China College of Humanities and Law Northeast UniversityShenyang 110169China

Following the trends of Chinese rural transformation development, and the sustainable development goals for resources and environment, reasonable arranging the potential development space and the ecological space, so as to optimize the distributions of rural settlement would be the key challenge for rural areas in ecologically fragile regions. From the perspective of maintaining regional ecological security, this paper takes Da’an City, a typical ecological fragile region in Jilin Province, as the case area, constructing the comprehensive ecological security pattern(ESP) on basis of landscape ecology, and applying the landscape pattern indexes to quantitative analysis the spatial distribution characteristics of rural settlements. Then, different optimization directions and management strategies are put forward for rural settlements in each secure zone under the comprehensive ESP. The experimental results showed that 1) the area of the low security zone, the general security zone, the moderate security zone and the extreme security zone was 1570.18 km^2, 1463.36 km^2, 1215.80 km^2 and 629.77 km^2, representing 32.18%, 29.99%, 24.92% and 12.91% of the total area of the target area, respectively. 2) The rural settlements in Da’an City were characterized by a high degree of fragmentation with a large number of small-scale patches. 3) The area of rural settlements in the ecological relocation zone, the in situ remediation zone, the limited development zone and the key development zone was 22.80 km^2, 42.31 km^2, 36.28 km^2 and 19.40 km^2, accounting for 18.88%, 35.03%, 30.04% and 16.06% of the total area of rural settlements, respectively. Then, different measures were proposed for settlements in different optimization zones in order to scientifically plan important ecological space, production space and living space in rural areas. This paper aims to provide fundamental support for rural settlements based on redistribution from the perspective of landscape ecology and p

关键词： ecologically fragile regions ecological security pattern(ESP) rural settlements Da’an City

Stability of Land-use/Land-cover in National Nature Reserves of Jilin Province, China

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Chinese Geographical Science 2022年第2期32卷 324-339页

作者： SHANG Yi wang dongyan LIU Shuhan LI Hong College of Earth Sciences Jilin UniversityChangchun 130012China School of Humanities and Law Northeastern UniversityShenyang 110169China

National nature reserves are an important part of classification management on ecological protection in China. Taking the national nature reserves of Jilin Province as examples, this paper introduced the stability index by referring to the intensity model of landuse and land-cover change(LUCC), and analyzed the overall stability of land-use and land-cover(LULC) in the study area from the time interval level and land category level. The stability of LULC in different types of nature reserves was tracked and identified by extracting land-use change trajectory, and the land-use change trajectory was divided into three types: stable type, sub-stable type and unstable type. The impact of LUCC on regional ecosystem services was studied by using hotspot analysis and gravity center analysis. The results showed that: 1) The LULC in the study area was stable on the whole, and the proportion of stable land area reached 86.08%. The intensity of LUCC showed an increasing trend in recent 20 years, and the conversion of cultivated land and construction land was active in continuous time interval. 2) The stability of LULC in forest ecological reserves and wildlife reserves in the eastern part of Jilin Province was the highest, while that in inland wetland reserves and geological relic reserves in the central and western part of Jilin Province was lower.3) The LUCC in national nature reserves not only changed the value of its own ecosystem service function, but also affected the ecosystem service function of the whole region. The combination of intensity analysis and land-use change trajectory was used to identify the characteristics of stability of LULC in nature reserves, which was conducive to deeply understand the process of LUCC in national nature reserves and provided reasonable suggestions for regional ecological protection.

关键词： national nature reserves land-use and land-cover change(LUCC) stability intensity analysis land-use change trajectory ecosystem service value

Discovery of dunite and pyroxenite xenoliths in Mesozoic diorite at Jinling,western Shandong and its significance

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Chinese Science Bulletin 2003年第15期48卷 1599-1604页

作者： XU Wenliang wang dongyan GAO Shan LIN Jingqian College of Earth Sciences Jilin University Changchun 130061 China The Key Laboratory of Continental Dy namics Northwestern University Xi'an 710069 China

Abundant deeply-derived xenoliths are discovered in a Mesozoic diorite at Jinling, Zibo, western Shandong, which mainly consist of dunite and pyroxenite. The dunite can be further subdivided into two subtypes. The first type shows tabular texture and high Mg# values (93—94) in olivines. The second type is characterized by the metamorphic-deformation texture superimposed by later metasomatism and relatively low olivine Mg# values (86—87). The mineral chemical data indicate that the former could be derived from ancient lithospheric mantle and the latter could have resulted from silica-rich melt metasomatism. The exsolution texture and the high Mg# value in clinopyroxenes, together with the rather high equilibrium temperature, imply that the pyroxenite xenoliths could be the cumulates of mantle-derived magma in the uppermost mantle or near the crust-mantle boundary in the Mesozoic.

关键词：纯橄榄岩辉岩捕虏岩闪长岩中生代山东地质学

Discovery of eclogite inclusions and its geological significance in early Jurassic intrusive complex in Xuzhou-northern Anhui, eastern China

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Chinese Science Bulletin 2002年第14期47卷 1212-1216页

作者： Wenliang Xu dongyan wang Xiaochun Liu Qinghai wang Jingqian Lin College of Earth Sciences Jilin University Changchun China Institute of Geomechanics Chinese Academy of Geological Sciences Beijing China

The early Jurassic intrusive complex is chiefly made of monzodioritic porphyry in northern Anhui and northern Jiangsu, which emplaced in 191 Ma. The intrusive complexes contain a lot of eclogite inclusions which belong to eclogite and garnet-pyroxenite. The inclusions had undergone eclogite facies high-pressure metamorphism and am-phibolite facies retrogressive metamorphism. The garnets in eclogite inclusions are mainly almandine varieties and clino-pyroxenes are omphacite and augite. The mineral assemblage and P-T estimation results show that P-T conditions of eclogite facies metamorphism and amphibolite facies retrogressive metamorphism are over 1.2-1.5 GPa, 709-861°C and 0.7-1.03 GPa, 666-738°C, respectively. The discovery of the high-pressure xenoliths not only is of important significance to understand the composition and structure of deep crust in southern edge of North China Platform, but also can be of important influence on realizing the subduc-tion-collision-exhumation evolutional process

关键词： Xuzhou-northern Anhui region early Jurassic intrusive complex eclogite inclusion geological significance.

Regeneration patterns and drivers of different underutilized lands in the rust belt city of developing country:An empirical case study for Northeast China

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Journal of Geographical Sciences 2023年第7期33卷 1377-1396页

作者： LI Wenbo LI Han YAN Zhuoran HU Bingqing ZHU Yuanli YANG Yuewen wang dongyan College of Earth Sciences Jilin UniversityChangchun 130061China School of Public Policy and Management China University of Mining and TechnologyXuzhou 221116JiangsuChina

Rust belt cities are largely threatened by a waste of urban space at their core;however,in developing countries where land resources are widely used as instruments for macroeconomic stabilization,urban periphery is also at risk of being underutilized due to land *** geographic differences entail new knowledge about how,where,and why underutilized lands are regenerated in the ***,rapid urban growth imposes development disparity and mixed underutilization issues on cities in developing countries;therefore,how the geo-information obtained by the regeneration of different underutilized lands differs will be valuable for urban planners and policymakers to make prudent *** fill these gaps,we conducted a sequential investigation into the regeneration of underutilized lands in a representative rust belt city – Changchun City in Northeast China,in an attempt to measure the regeneration pattern and analyze the underlying determinants using the Classification and Regression Trees *** results indicated that,of all underutilized lands,increments of vacant lot and remnant cultivated land continued to plague the expanding urban periphery during 2016–*** a way,reduced underutilized lands alleviated land use conflicts at the city *** 23% of the underutilized areas had been regenerated,dominated by realty development,with most converted to residential lands,ecological lands and industrial *** the contrary,conversion to transportation lands and parking lots seemed to avoid the rapidly expanding *** regeneration rates in a certain area can be increased by a multitude of factors,including denser,simply structured land underutilization,abundant ecosystem services nearby and accessibility to public *** conditions such as residential density and accessibility may have fueled the regeneration associated with residential purposes,while regeneration of industrial development was closely associated with the under

关键词： land underutilization spatial-statistical analysis driving mechanism developing country rust belt of Northeast China

Kinetics of Evaporation of Zn and Pb from Carbon-bearing Pellets Made of Dust Containing Zn-Pb-Fe Oxides

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International Journal of Minerals,Metallurgy and Materials 2000年第3期14卷 178-183页

作者： Weiqing Chen, dongyan wang, Rongzhang Zhou, Zongcai Lin (Metallurgy School, University of Science and Technology Beijing, Beijing 100083, China) Metallurgy School University of Science and Technology Beijing Beijing 100083 China

The influence of reduction temperature, size of coal powder and the carbon content on the evaporation rates of Zn and Pb in pellets made of ZnO-PbO-FeO bearing dust has been investigated between 1100-1300℃. The evaporation rate of Zn and Pb obtained from the experiments has been analyzed with kinetic models. The results show that the control step for evaporation of Zn is reduction reaction of ZnO by CO at the interface，and that the evaporation rate of Pb is controlled by the volatilization of reduction products, i.e. liquid lead. The overall apparent activation energies of Zn and Pb evaporation from the pellet are 79.42kJ/mol and 88.74kJ/mol respectively.

关键词： Zn-Pb-bearing dust carbon-containing pellet evaporation kinetics

Molecular analysis of Coxsackievirus A24 variant isolates from three outbreaks of acute hemorrhagic conjunctivitis in 1988,1994 and 2007 in Beijing,China

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Virologica Sinica 2022年第2期37卷 168-176页

作者： Junhan Li Fang Huang Yong Zhang Tianjiao Ji Shuangli Zhu dongyan wang Zhenzhi Han Jinbo Xiao Fenfen Si Wenbo Xu Dongmei Yan National Polio Laboratory WHO WPRO Regional Polio Reference LaboratoryNational Health Commission Key Laboratory for BiosecurityNational Health Commission Key Laboratory for Medical VirologyNational Institute for Viral Disease Control and PreventionChinese Center for Disease Control and PreventionBeijing102206China Nanguan District Center for Disease Control and Prevention Changchun130042China Beijing Center for Disease Control and Prevention Beijing100000China Center for Biosafety Mega-Science Chinese Academy of SciencesWuhan430000China

Coxsackievirus A24 variant(CVA24v)is a major pathogen that causes continued outbreaks and pandemics of acute hemorrhagic conjunctivitis(AHC).In China,the first confirmed outbreak of CVA24v-related AHC occurred in Beijing in 1988,followed by another two significant outbreaks respectively in 1994 and 2007,which coincides with the three-stage dynamic distribution of AHC in the world after *** illustrate the genetic characteristics of CVA24v in different periods,a total of 23 strains were isolated from those three outbreaks and the whole genome of those isolations were sequenced and *** with the prototype strain,the 23 strains shared four nucleotide deletions in the 5'UTR except the 0744 strain isolated in *** at the 98th site,one nucleotide insertion was found in all the strains collected from *** 1994 to 2007,amino acid polarity in the VP1 region at the 25th and the 32nd site were *** the 3C and VP1 phylogenetic tree indicated that isolates from 1988 and 1994 belonged to Genotype III(GIII),and 2007 strains to Genotype IV(GIV).According to the Bayesian analysis based on complete genome sequence,the most recent common ancestors for the isolates in1988,1994 and 2007 were respectively estimated around October 1987,February 1993 and December *** evolutionary rate of the CVA24v was estimated to be 7.45×10^(-3) substitutions/site/*** study indicated that the early epidemic of CVA24v in Chinese mainland was the *** mutations and amino acid changes in different genotypes of CVA24v may generate intensity differences of the AHC ***24v has been evolving constantly with a relatively rapid rate.

关键词： Coxsackievirus A24 variant(CVA24v) Acute hemorrhagic conjunctivitis(AHC) Phylogenetic analysis Complete genome sequence

A neural regulation mechanism of head electroacupuncture on brain network of patients with stroke related sleep disorders

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Journal of Traditional Chinese Medicine 2024年第6期44卷 1268-1276页

作者： ZHANG Boyang ZHOU Yang FENG Liyuan SUI Dan HE Lei TONG Dan wang Ruoyu SUI Xue SONG Jing wang dongyan Rehabilitation Department Wuxi Hospital of Traditional Chinese Medicine Imaging Department Harbin Medical University Cancer Hospital Acu-Moxi Department Ⅲ the Second Affiliated Hospital of Heilongjiang University of Traditional Chinese Medicine Rehabilitation Department B Second Hospital of Harbin Acu-Moxi Department Lianyungang Hospital of Traditional Chinese Medicine Integrated TCM and Western Medicine Department Suzhou Dushu lake hospital Internal Medicine Department Zhaozhou Hospital of Traditional Chinese Medicine

OBJECTIVE: To analyze part of the mechanism of electroacupuncture on Sishencong(EX-HN1) for strokerelated sleep disorders(SSD) and post-stroke cognitive impairment(PSCI). METHODS: Using a randomized controlled trial(RCT) design, 72 patients were assigned to the electroacupuncture(EA) group or the sham acupuncture(SA) group. A healthy control(HC) group was also included. Both groups were given routine rehabilitation treatment. Then, patients in the EA group were given additional electroacupuncture at Sishencong(EX＿HN1). Meanwhile, patients in the SA group were given a flat-head needle sham/placebo treatment placed at the bilateral Jianyu (LI15) and Binao(LI14) line midpoints and the Jianyu(LI15) and Jianzhen(SI9) line midpoints. Before and after treatment, scales were collected and analyzed. In the second phase of the study, some subjects from the EA group were selected for functional magnetic resonance imaging(f MRI) data acquisition and comparative analysis with the HC group using a non-RCT design. RESULTS: The EA group performed better than the SA group on the Pittsburgh sleep quality index(PSQI), Montreal cognitive assessment basic(Mo CA＿B), selfrating anxiety scale(SAS), and self-rating depression scale(SDS). Analysis of the f MRI showed that lowfrequency(2 Hz) electroacupuncture stimulation at Sishencong(EX＿HN1) can restrain frontal sup medial right(SFGmed.R), precuneus right(PCUN.R), and posterior cingulate cortex right(PCC.R) and enhance angular left(ANG.L), parietal inf left(IPL.L) and occipital mid left(MOG.L). The functional connectivity(FC) of SFGmed.R was positively correlated with PSQI. Electroacupuncture stimulation at Sishencong(EX＿HN1) can reduce the side efficiency of the whole brain connection with the Thalamus.L, Hippocampus.L, and ***.L. CONCLUSIONS: Low frequency(2 Hz) electroacupuncture stimulation at Sishencong(EX＿HN1) can simultaneously improve sleep quality, negative emotions, and cognitive functions, the first two of which may be

关键词： brain network electroacupuncture neural regulation sleep disorder