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Concentrations and light absorption properties of PM_(2.5) organic and black carbon based on online measurements in lanzhou, China

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Journal of Environmental Sciences 2023年第9期131卷 84-95页

作者： Pengfei Chen Shichang Kang Qinyi Gan Ye Yu Xianlei Yuan Yajun Liu Lekhendra Tripathee Xiaoxiang Wang Chaoliu Li State Key Laboratory of Cryospheric Science Northwest Institute of Eco-Environment and ResourcesChinese Academy of Sciences(CAS)Lanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China College of Earth and Environmental Sciences Lanzhou UniversityLanzhou 730000China Key Laboratory of Land Surface Process and Climate Change in Cold and Arid Regions Northwest Institute of Eco-Environment and ResourcesCASLanzhou 730000China Xinjiang Bayingolin Mongolian Autonomous Prefecture Meteorological Bureau Korla 841000China

To elucidate the variations in mass concentrations of organic carbon(OC)and black carbon(BC)in PM_(2.5) and their light absorption characteristics in lanzhou,we conducted one-year online measurements by using a newly developed total carbon analyzer(TCA08)coupled with an aethalometer(AE33)from July 2018 to July *** mean OC and BC concentrations were 6.4±4.4 and 2.0±1.3μg/m^(3),*** seasonal variations were observed for both components,with winter having the highest concentrations,followed by autumn,spring,and *** diurnal variations of OC and BC concentrations were similar throughout the year,with daily two peaks occurring in the morning and evening,respectively.A relatively low OC/BC ratio(3.3±1.2,n=345)were observed,indicating that fossil fuel combustion was the primary source of the carbonaceous *** is further substantiated by relatively low biomass burning contribution(f_(biomass):27.1%±11.3%)to BC using aethalometer based measurement though f_(biomass) value which increased significantly in winter(41.6%±5.7%).We estimated a considerable brown carbon(BrC)contribution to the total absorption coefficient(b_(abs))at 370 nm(yearly average of 30.8%±11.1%),with a winter maximum of 44.2%±4.1%and a summer minimum of 19.2%±4.2%.Calculation of the wavelength dependence of total b_(abs) revealed an annual mean AAE_(370-520) value of 4.2±0.5,with slightly higher values in spring and *** mass absorption cross-section of BrC also exhibited higher values in winter,with an annual mean of 5.4±1.9 m^(2)/g,reflecting the impact of emissions from increased biomass burning on BrC concentrations.

关键词： Black carbon Brown carbon Light absorption Source lanzhou

RESEARCH ON IMAGO SPACE OF VALLEY CITY——A Case Study of lanzhou City

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Chinese Geographical Science 2004年第3期14卷 283-288页

作者： MENGCai-hong YANGYong-chun ZHANGCong-guo CollegeofResourcesandEnvironment LanzhouUniversityLanzhou730000P.R.China

Currently domestic researches on urban imago space concentrate in a few cities that lie in the advanced region, such as Beijing, Guangzhou, Wuhan, etc., but in so far as those cities that lie in the northwest inland region, the research of this aspect is still few. In order to supplement a special example to the urban imago space theory and to validate former theory, this article studied the lanzhou urban imago space. During the course of researching, authors adopted some investigating methods, such as visiting on the spot, photograph identification method and sketch map identification method etc. Using investigated data, this paper made an elementary research on urban imago space of lanzhou, which is a typical valley city in the western China. The result of study indicated that the urban imago space of lanzhou takes Xiguan Cross as its center (lanzhou involves four districts of Chengguan, Qilihe, Anning and Xigu). In the process of recognition of urban imago space, the Huanghe (Yellow) River and mountains beside the city are the dominant factors and the main nodes of cognition. So the urban imago space of lanzhou is quite different from that of plain cities. Interviewee did well in the spatial structure map, which was made up of mountainous land, river and main trunk roads,the group structure took profound impression on people.

关键词： lanzhou urban imago space valley city node

Radioactive ion beam line in lanzhou

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Science China Mathematics 1999年第5期42卷 528-536页

作者：詹文龙郭忠言刘冠华党建荣何锐荣周嗣信尹全民罗亦孝王义芳魏宝文孙志宇肖国青王金川江山红李加兴孟祥伟张万生秦礼军王全进 1. Institute of Modern Physics Chinese Academy of Sciences 730000 Lanzhou China

Radioactive ion beam line in lanzhou (RIBLL) has been constructed for the production of short-lived radioactive nuclei and studies of exotic nuclei far from the β-stability line. It has been put into operation recently at the National Laboratory of Heavy Ion Accelerator lanzhou. RIBLL consists of two doubly achromatic parts with a solid acceptance ΔΩ?6.5 msr, momentum acceptance Δp/p=±5% and maximum magnetic rigidityBp max=4.2 Tm. The second part of RIBLL serving as a spectrometer gives an element resolutionZ/ΔZ>150 and mass resolutionA/ΔA>300. The polarized secondary beams can be obtained by using a swinger dipole magnet to change the incident direction of primary projectile from 0° to 5°. The shortest lift time for secondary beams on RIBLL is less than 1 μs. First experiments were performed with neutron rich nuclei for understanding the properties of halo nuclei and exotic nuclear reactions.

关键词： radioactive ion beam line in lanzhou radioactive nuclear beams projectile fragmentation.

Magnetostratigraphy and paleoenvironmental record of Tertiary deposits of lanzhou Basin

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Chinese Science Bulletin 2001年第9期46卷 770-774页

作者： YUE Leping F.Heller QIU Zhanxiang ZHANG Li XIE Guangpu QIU Zhuding ZHANG Yunxiang Department of Geology Northwest UniversityXi’an 710069China Institute of Geophysics ETH-HonggerbergCH-8093 ZurichSwitzerland Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of SciencesBeijing 100044China Provincial Museum of Gansu Lanzhou 730050China

The Tertiary deposits of the Yongdeng section, the lanzhou Basin were studied by means of magnetostrati-graphy. The magnetostratigraphic sequences from Paleocene to Miocene were established, and the time scale for the corresponding stratigraphy and mammalian faunas was also established by referring to their correlation to the GPTS of BKSA95 (The geomagnetic polarity time scale which was thoroughly revised and updated by Berggreen et al. in 1995). In the end the paleoenvironmental records and their relationship with the uplifting of the Tibetan Plateau were discussed. The results are as follows. The top boundary of the Xiliugou Formation is dated to be 51 Ma, i.e. Eocene. TheYehucheng Formation covers the time span of 51-31.5 Ma, i.e. from late Early Eocene to early Early Oligocene. The Xianshuihe Formation covers the time span of 31.5-15 Ma, i.e. from Early Oligocene to Middle Miocene. The lower member of the Xianshuihe Formation spans from 31.5 to 20.0 Ma, i.e. from Early Oligocene to early Early

关键词： paleomagnetic stratigraphy lanzhou Basin Tertiary the Tibetan Plateau paleoenvironment.

A STUDY ON LANDSCAPE MOSAIC STRUCTUREIN URBANRURAL AREA IN NORTHWESTOF CHINA WITH RS AND GIS- A Case Study of Xigu District in lanzhou City

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Chinese Geographical Science 2001年第4期11卷 80-90页

作者： XU Jian-hua1, LU Yan1, AI Nan-shan2, YUE Wen-ze3(1. Department of Geography, East China Normal University, Shanghai 200062, P. R. China 2. Environmental Science and Engineering School, Sichuan University, Chengdu 610064, P. R. Chin Department of Geography East China Normal University Shanghai P. R. China Environmental Science and Engineering School Sichuan University Chengdu P. R. China Department of Geography Lanzhou University Lanzhou P. R. China

ABSTRACT: At the study area of Xigu District in lanzhou City, using RS & GIS as tools we apply Diversity, Dominance, Fragmentation , Isolation and so on to study the quantitative, fractal and spatial characters of landscapes’ structures in the four sub-regions divided by the morphological features. Using the Fractal Theory to establish the fractal structure models, we analyze the complexity and stability of various landscapes’ distribution with fractal dimension value. The spatial distribution characteristics of landscape mosaic structure are also expounded. At the end of the paper we discuss the relevant problems on the main factors which control and effect on the spatial pattern of landscapes as well as on landscape optimization and management.

关键词： landscape mosaic spatial structure fractal Xigu District in lanzhou City

HEAVY ION RESEARCH FACILITY AT lanzhou (HIRFL)

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Chinese Science Bulletin 1989年第13期34卷 1057-1060页

作者：魏宝文叶峰张恩厚马受武白国良乔庆文 Institute of Modern Physics Academia Sinica Lanzhou

As the further development of heavy ion physics requires much modern facilities, the possibility of building a new heavy ion research facility in lanzhou (HIRFL) was therefore surveyed. The idea of using the existing ... 详细信息

关键词： facilities sector facility lanzhou surveyed constructing possibility focusing converted separated

THE COMPARISON OF lanzhou LOESS PROFILE WITH VOSTOK ICE CORE IN ANTARCTICA OVER THE LAST GLACIATION CYCLE

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Science China Chemistry 1992年第4期35卷 476-488页

作者：李吉均朱俊杰康建成陈发虎穆德芬曹继秀唐领余张宇田潘保田 Geography Department Lanzhou University Lanzhou 730000 PRC Nanjing Instirute of Geology and Palaeontology Academis SinicaNanjing 210008 PRC

Loess near lanzhou in the late Pleistocene is very sensitive to climatic fluctuations. The Beiyuan terrace profile in Linxia City, of which the curve of susceptibility tallies with the trend of isotopic curves of Vostok 2083 m ice core in Antarctica, is 35m thick. There are five layers of paleosols under Malan loess(L_1). Upper three layers (S_(1-a),S(1-b)and S_(1-c) correspond to three warm stages in last interglaciation, Interstadial of Last Glacial (C stage in Antarctic ice core)was clearly recorded in the Beiyuan profile, in which three layers of paleosols and two of loess were formed. The lowest section of the profile belongs to penultimate glaciation, in which fossils of cold-drought-resistant mammal and mollusc have been discovered.

关键词： lanzhou Late Pleistocene loess curve of susceptibility Antarctic ice core.

Optimizing Urban Spatial Structure of lanzhou Based on Geographic Concentration Method of Industries

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Chinese Journal of Population,Resources and Environment 2007年第1期5卷 58-62页

作者： Zhu Shuang Chen Xiaojian College of Architecture Xi＇an University of Architecture ＆ Techonology Xi＇an Shanxi 710055 China

Geographic concentration of industries is the regional- ized distribution of some industries in certain areas, which focuses on the ratio of a certain industry to the whole industries (He and Liu, 2006). In this paper we explore the improved M function of geographic concentration that adds the parameter of the number of firms according to the definition of geographic concentration of industries. The spatial distribution of the main manufacturing industries of lanzhou urban area is evaluated based on it. The results of the evaluation imply that the spatial distribution of the main manufacturing industries is more concentrated than that of others in lanzhou and it can absorb lots of labor forces. But the incidence, competition ability and density of the distribution of enterprises are different for each single sector, and enterprises with different production features are located closely. And three main problems are discovered. Finally, three countermeasures are put forward: locating the industrial enterprises in urban areas in a proper way through planning and policies; adjusting the industrial structure of the inner city; strengthening the local rearrangement of the existing industrial concentration areas.

关键词： geographic concentration of industries urban spatialstructure lanzhou

From Continuation to Evolution: Historic Review and Value Enlightenment of the lanzhou Urban Construction Plan

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China City Planning Review 2018年第4期27卷 69-75页

作者： Tang Xianglong Wang De Li Baihao Liu Jinxin School of Architecture & Urban Plan-ning Lanzhou Jiaotong University College of Architecture and Urban Planning Tongji University School of Architecture Southeast University

This paper provides a holistic picture of the Draft Outline of the lanzhou Urban Construction Plan in 1951 and the Work Report of the lanzhou New Urban Construction Plan from 1952 directed by Chief Ren Zhenying of the lanzhou Municipal Construction Department. The author analyzes the changing process of planning thoughts from "industry as subsidiary" to "industry-oriented," putting these plans into the macro context of national social system reform and economic recovery during the early years of new China, and analyzes the evolution of the planning paradigm from the explicit continuation of European and American model to the implicit intervention of Soviet model. It is believed that the influencing process of the European and American model and other foreign urban planning ideas is not continuous, and obviously has phased and partial features. The evolving process of the urban construction plan in lanzhou from 1951 to 1952 is historically representative, which manifests the transition history of an early Chinese planning paradigm from the European and American model toward a Soviet model.

关键词： urban planning planning paradigm European and American model Soviet model lanzhou City