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Paleoclimate evolution and aridification mechanism of the eastern Tethys during the Callovian–Oxfordian: evidence from geochemical records of the Qiangtang Basin, Tibetan Plateau

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Acta Geochimica 2021年第2期40卷 199-211页

作者： Yongyao Zeng Lei Gao Wenqing Zhao lanzhou resources and environment voc-tech college Lanzhou 730000China

Global climate during the Jurassic has been commonly described as a uniform greenhouse climate for a long ***,the climate scenario of a cool episode during the Callovian-Oxfordian transition following by a warming trend during the Oxfordian(163.53 to157.4 Ma)is documented in many localities of the western *** is still unclear if a correlatable climate scenario also occurred in the eastern Tethys during the same time *** this study,a detailed geochemical analysis on the 1060 m thick successions(the Xiali and Suowa formations)from the Yanshiping section of the Qiangtang Basin,located in the eastern Tethys margin during the Callovian-Oxfordian periods,was *** reveal the climate evolution of the basin,carbonate content and soluble salt concentrations(SO_(4)^(2-),Cl^(-))were chosen as climatic *** results show that the overall climate patterns during the deposition of the Xiali and Suowa formations can be divided into three stages:relatively humid(164.0 to 160.9 Ma),dry(160.9 to159.6 Ma),semi-dry(159.6 to 156.8 Ma).A similar warming climate scenario also occurred in eastern Tethys during the Callovian-Oxfordian transition(160.9 to159.6 Ma).Besides,we clarify that the Jurassic True polar wander(TPW),the motion of the lithosphere and mantle with respect to Earth’s spin axis,inducing climatic shifts were responsible for the aridification of the Qiangtang Basin during the Callovian-Oxfordian transition with a review of the paleolatitude of the Xiali formation(19.7+2.8/-2.6°N)and the Suowa formation(20.7+4.1/-3.7°N).It is because the TPW rotations shifted the East Asia blocks(the North and South China,Qiangtang,and Qaidam blocks)from the humid zone to the tropical/subtropical arid zone and triggered the remarkable aridification during the Middle-Late Jurassic(ca.165-155 Ma).

关键词： Qiangtang basin The Callovian–Oxfordian Geochemistry Paleolatitude Paleoclimate

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Preparation of nickel nanoparticles in emulsion

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中国有色金属学会会刊：英文版 2008年第1期18卷 212-216页

作者：张有贤付文杰安学勤 college of resources and environment Lanzhou University

The nickel nanoparticles with different sizes and spherical shape were prepared by the reduction of nickel sulfate with sodium borohydride in the water-in-oil emulsions of water/SDBS(sodium dodecylbenzene sulfonate)/n-pentanol/*** effects of aging time,molar ratio of water to SDBS(R)and the concentration of nickel sulfate on the size of particles were *** samples were characterized by transmission electron microscopy(TEM)and inductively coupled plasma spectrometry(ICP).The results show that the average particle size changes from 20 to 40 nm by adjusting aging time(15-30 min)and R(9-11.5).The concentration of nickel sulfate of 1.0 mol/L is the favorite condition.

关键词： W/O乳剂镍乳状液制备方法稀有金属

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Finite-thickness effect of the fluids on bubbles and spikes in Richtmyer–Meshkov instability for arbitrary Atwood numbers

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Plasma Science and technology 2019年第2期21卷 9-15页

作者： Wanhai LIU Changping YU Pei WANG Zheng FU Lili WANG Yulian CHEN Research Center of Computational Physics Mianyang Normal University LHD Institute of MechanicsChinese Academy of Sciences Institute of Applied Physics and Computational Mathematics Mechanical and Electrical Engineering Department Lanzhou Resources and Environment Voc-Tech College

This paper investigates the finite-thickness effect of two superimposed fluids on bubbles and spikes in Richtmyer–Meshkov instability(RMI) for arbitrary Atwood numbers by using the method of the small parameter expansion up to the second order. When the thickness of the two fluids tends to be infinity, our results can reproduce the classical results where RMI happens at the interface separating two semi-infinity-thickness fluids of different densities. It is found that the thickness has a large influence on the amplitude evolution of bubbles and spikes compared with those in classical RMI. Based on the thickness relationship of the two fluids, the thickness effect on bubbles and spikes for four cases is discussed. The thickness encourages(or reduces)the growth of bubbles or spikes, depending on not only Atwood number, but also the relationship of the thickness ratio of the heavy and light fluids, which is explicitly determined in this paper.

关键词： Richtmyer–Meshkov instability bubbles and spikes finite-thickness

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Study on the Employment-oriented Teaching Quality Management System of Higher vocational colleges

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International Journal of technology Management 2015年第9期 87-89页

作者： Zhe JI lanzhou resources and environment voc-tech college

In this paper, the general idea and quality assurance for the teaching quality management system of higher vocational colleges are proposed. A teaching quality management system for higher vocational colleges is constructed and studied to help these schools clearly know the development ideas and accordingly improve the core school competitiveness, and eventually promote a continuous long-term development.

关键词： Employment-orientation Higher vocational colleges Teaching Quality Management

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Lexical Negative Transfer in English Writing

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读与写(教育教学刊) 2014年第2期11卷 1-2页

作者： Wan Lian lanzhou resources and environment voc-tech college

English writing,which shows students’ comprehensive competence of language, requires students to master the ability of applying language by using some strategies and skills. The negative transfer of native language is a phenomenon that can not be neglected in English writing,it is the main obstacle to improving the level of English writing for Chinese students. To improve the quality of students’ English writing and eliminate or minimize the interference of the negative transfer of native language in English writing, the author discusses the lexical negative transfer in English writing from three types, namely erros in word choice,erros in collactions and errors in different word classes and proposes four corresponding strategies in English writing.

关键词： lexical negative transfer English writing strategies

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Causes and Changes of Drought in China:Research Progress and Prospects

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Journal of Meteorological Research 2020年第3期34卷 460-481页

作者： Qiang ZHANG Yubi YAO Yaohui LI Jianping HUANG Zhuguo MA Zhilan WANG Suping WANG Ying WANG Yu ZHANG lanzhou Institute of Arid Meteorology of China Meteorological Administration(CMA) and Key Laboratory of Arid Climate Change and Disaster Reduction of Gansu Province and CMALanzhou 730020 Gansu Provincial Meteorological Service Lanzhou 730020 lanzhou resources&environment voc–tech college Lanzhou 730021 college of Atmospheric Sciences Lanzhou UniversityLanzhou 730000 Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029

Drought is one of the most serious and extensive natural hazards in the *** to monsoon climate variability,China is particularly influenced by drought hazards,especially meteorological *** on a comprehensive understanding of the current status of international drought research,this paper systematically reviews the history and achievements of drought research in China since the founding of the People’s Republic of China,from four main perspectives:characteristics and spatiotemporal distribution of historical and recent drought events,drought formation mechanism and change trend,drought hazard risk,and the particular flash *** progress and problems of drought research in China are analyzed and future prospects are proposed,with emphasis on the multi-factor synergetic effect for drought formation;the effect of land-atmosphere interaction;identification,monitoring,and prediction of flash drought;categorization of drought and characteristics among various types of drought;the agricultural drought development;drought response to climate warming;and assessment of drought hazard *** is suggested that strengthening scientific experimental research on drought in China is *** present review is conducive to strategic planning of drought research and application,and may facilitate further development of drought research in China.

关键词： drought meteorological drought formation mechanism change trend drought hazard risk flash drought

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Application of 3D Digital Modeling technology in the Construction of Digital Cities

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Journal of Geographic Information System 2023年第1期15卷 98-109页

作者： Xuke Wang lanzhou resources & environment voc-tech University Lanzhou China

The concepts of “digital twins”, “3D real scene”, “metacosm” and others were the technical paths for building digital cities with the development of emerging surveying and mapping science and technology, which was to build a digital and virtualized city that matched the real physical world, to achieve a one-to-one correspondence between all elements of the physical world and the digital virtual world. And one of its basic geographic information data was a highly similar, virtual simulation of the 3D real scene. After exploring the traditional manual 3DsMax modeling, UAV low-altitude digital oblique photogrammetry modeling, airborne laser scanning modeling and other single modeling technologies, this paper discussed the 3D digital modeling technology used by the UAV airborne laser scanning point cloud and low-altitude digital oblique photogrammetry for complementary integration, constructing the 3D scene of the digital city. This paper expounded the technical route and production process of 3D digital modeling, in order to provide technical references for related projects.

关键词： Airborne Laser Scanning Point Clouds Low-Altitude Oblique Photogrammetry Real Scenes Digital City Digital Twins

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Response of Biomass Spatial Pattern of Alpine Vegetation to Climate Change in Permafrost Region of the Qinghai-Tibet Plateau,China

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Journal of Mountain Science 2010年第4期7卷 301-314页

作者： ZHANG Yu WANG Genxu WANG Yibo college of resources & environment Lanzhou UniversityLanzhou 730000China Institute of Mountain Hazards and environment Chinese Academy of SciencesChengdu 610041China

Alpine ecosystems in permafrost region are extremely sensitive to climate *** determine spatial pattern variations in alpine meadow and alpine steppe biomass dynamics in the permafrost region of the Qinghai-Tibet Plateau,China,calibrated with historical datasets of above-ground biomass production within the permafrost region's two main ecosystems,an ecosystem-biomass model was developed by employing empirical spatialdistribution models of the study region's precipitation,air temperature and soil *** model was then successfully used to simulate the spatio-temporal variations in annual alpine ecosystem biomass production under climate *** a 0.44°C decade-1 rise in air temperature,the model predicted that the biomasses of alpine meadow and alpine steppe remained roughly the same if annual precipitation increased by 8 mm per decade-1,but the biomasses were decreased by 2.7% and 2.4%,respectively if precipitation was *** a 2.2°C decade-1 rise in air temperature coupled with a 12 mm decade-1 rise in precipitation,the model predicted that the biomass of alpine meadow was unchanged or slightly increased,while that of alpine steppe was increased by 5.2%.However,in the absence of any rise in precipitation,the model predicted 6.8% and 4.6% declines in alpine meadow and alpine steppe biomasses,*** response of alpine steppe biomass to the rising air temperatures and precipitation was significantly lesser and greater,respectively than that of alpine meadow biomass.A better understanding of the difference in alpine ecosystem biomass production under climate change is greatly significant with respect to the influence of climate change on the carbon and water cycles in the permafrost regions of the Qinghai-Tibet Plateau.

关键词： Permafrost change Qinghai-TibetanPlateau Alpine ecosystem Grassland biomass Climate change Response model

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Sedimentary Conditions of Evaporites in the Late Jurassic Xiali Formation,Qiangtang Basin：Evidence from Geochemistry Records

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Acta Geologica Sinica(English Edition) 2017年第1期91卷 156-174页

作者： SONG Chunhui ZENG Yongyao YAN Maodu FANG Xiaomin FENG Ying PAN Jiaqiu LIU Xifang MENG Qingquan HU Chunhua ZHONG Sirui School of Earth Sciences ＆ Key Laboratory of Western China's Mineral resources of Gansu Province Lanzhou University Lanzhou 730000 China CAS Center for Excellence in Tibetan Plateau Earth Sciences ＆ Key Laboratory of Continental Collision and Plateau Uplift Institute of Tibetan Plateau Research Chinese of Academy of Sciences Beijing 100101 China lanzhou resources ＆ environment voc-tech college Lanzhou 730000 China Institute of Mineral resources Chinese Academy of Geological Sciences ＆ Key Laboratory of Saline Lake Resources and Environment Ministry of Land and Resources Beijing 100037 China

The Qiangtang Basin（QB）, located in the central Tibetan Plateau, is a Jurassic marine basin and one of the most important prospective salt resource belts in China. In recent decades, many outcrops of gypsiferous bed have been found in the Jurassic marine strata in the basin. Salt springs with abnormally high sodium（Na-＋） contents had been identified in the Late Jurassic Xiali Formation（Fm.） in the basin in the last years. However, to date, no potash or halite deposits have been identified in the QB. Gypsum outcrops and salt springs are very important signs in the investigation of halite and potash deposits. Therefore, the Xiali Fm. is a potentially valuable layer to evaluate for the possible presence of halite and potash deposits in the basin. However, few studies have explored the formation conditions of evaporites in the unit. Here, we present detailed geochemical records from the Yanshiping section related to the study of the formation conditions of evaporites in the Xiali Fm. of the QB. Climate proxies based on the obviously increased anion concentrations of SO4（2-） and Cl-- and the significant correlation coefficients of Ca2＋-SO42-（R = 0.985） and Na-＋-Cl--（R = 0.8974） reveal that the upper member of the Xiali Fm.（the upper Xiali Fm.） formed under an arid climate and evolved into the sulfate phase or early chloride phase. Provenance proxies based on the obviously increased K-＋ and Na-＋ ion concentrations and the significant correlation coefficient of Na-＋-Cl--（R = 0.8974） suggest that the upper Xiali Fm. featured optimal provenance conditions for the possible formation of halite deposits. The regression and the semi-closed tidal flat environment in the upper Xiali Fm. were favorable for the formation of potash and halite deposits. The low Mg-（2＋） /Ca-（2＋） values（mean value = 1.82） and significant Na-＋-Cl-- correlation coefficient（R = 0.8974） also suggest that the upper Xiali Fm. is the layer most likely to contain potential halite deposits. In addition, the macr

关键词： Evaporites geochemistry Late Jurassic Xiali Formation Qiangtang Basin

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Comparative Analysis of Automatic Observation Data of DSG3 Precipitation Phenomenon Instrument and Manual Observation Data

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Meteorological and environmental Research 2021年第3期12卷 29-31页

作者： Yanwei ZONG lanzhou resources&environment voc-tech college Lanzhou 730021China

The observation data collected by DSG3 precipitation phenomenon observation instrument and the manual parallel observation data in 5 stations of Gansu Province from January 2018 to December 2019 were compared and *** results show that the missing observation rate of the observation instrument was 0%,and the performance of the equipment was good;the empty forecast rate of drizzle was the highest;the false forecast rate of hail was the highest,and the accuracy of automatic observation records was relatively poor;the capture rate and empty forecast rate of rain and snow were higher,while their false forecast rate and missing forecast rate were *** capture rate and missing forecast rate of sleet were higher,and its missing forecast rate was low;the accuracy of automatic observation was *** shows that the empty forecast and false forecast of DSG3 precipitation phenomenon observation instrument mainly occurred in weak precipitation phenomena,and the recognition of drizzle and hail was poor.

关键词： DSG3 precipitation phenomenon observation instrument Manual observation Accuracy Comparative analysis

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