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A statistical test on diversity changes of Early and Middle Permian fusulinacean fauna in South China

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Science China Earth Sciences 2005年第7期48卷 978-984页

作者： shi yukun YANG Xiangning Department of Earth Sciences Nanjing University Nanjing 210093 China Department of Earth Sciences Nanjing University Nanjing 210093 China

The rarefaction analysis has been conducted to test the species diversity changes of the Early and Middle Permian fusulinacean fauna in South China. The results reveal that the number of species dramatically increased since the earliest Permian and quickly reached the maximum value in the early Zisongian representing the highest species diversity for the whole Early and Middle Permian. The species diversity stabilized in the plateau through the Zisongian; however, it started to decline in the following Longlinian and sustained a longstanding low level during the mid-Early Permian. With the appearance of new fusulinacean taxa with septulum structures, the number of species raised again in the late-Early Permian, followed by a decline in the Middle Permian Neoschwagerina simplex zone. Although the species diversity increased apparently in the Kuhfengian, it never rebounded back to the same level as in the Early Permian. In the mid-Middle Permian, species diversity began to decrease continuously and led to the disappearance of most fusulinacean species by the end of the Middle Permian.

关键词： South China Permian fusulinacean fauna diversity statistical test.

Climate policy uncertainty and corporate investment:evidence from the Chinese energy industry

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Carbon Neutrality 2022年第1期1卷 439-449页

作者： Xiaohang Ren yukun shi Chenglu Jin School of Business Central South UniversityChangsha 410083HunanChina Adam Smith Business School University of GlasgowGlasgow G128QQUK School of Finance Zhejiang University of Finance and EconomicsHangzhou 310018China

In recent years,with the increasing attention paid to climate risks,the changes in climate policies are also more full of uncertainties,which have brought tremendous impact to economic entities,including *** the dynamic threshold model,this study investigates the nonlinear and the asymmetric effect of climate policy uncertainty on Chinese firm investment decisions with panel data of 128 Chinese energy-related companies from 2007 to *** empirical findings indicate that the influence of climate policy uncertainty on firm investment is significantly ***,climate policy uncertainty is not apparently related to corporate investments in the high-level range,while it negatively affects the investments in the low-level *** addition,to be more specific,the negative impact of climate policy uncertainty on the mining industry is tremendous,while the influence on the production and supply of electricity,heat,gas,and water sector is remarkably *** results of this study could help the company managers and policymakers to arrange appropriate related strategies under different climate policy conditions.

关键词： Dynamic threshold model Climate policy uncertainty Corporate investment

Lithologic Boundaries in Permian Post-glacial Sediments of the Gondwana-affinity Regions of China:Typical Sections,Age Range and Correlation

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Acta Geologica Sinica(English Edition) 2011年第2期85卷 373-386页

作者： JIN Xiaochi HUANG Hao shi yukun ZHAN Lipei Institute of Geology Chinese Academy of Geological Sciences26 Baiwanzhuang Road Beijing 100037 China Department of Earth Sciences Nanjing Univeristy22 Hankou Road Nanjing Jiangsu 210093 China

In Southwest China, Gondwana-affinity Permo-Carboniferons deposits are known to occur in the Northern Himalayas, the Lhasa Block and the South Qiangtang Block, the Baoshan Block and the Tengchong Bock. The three-fold clastic successions, namely diamictite-pebbly mudstone-dark mudstone and shale are commonly interpreted as representing deposits of glacial-deglacial-postglacial periods in marine environments. Deposits, for example, the Dingjiazhai Formation in the Baoshan Block, the Kongshuhe Formation in the Tengchong Block, the Yongzhu Group and the Poindo Group in the Lhasa Block, are all succeeded by carbonate deposits. This marks a significant change from post-glacial clastic environment to a carbonate environment. Available paleontological data show that the change from post-glacial clastic environment to carbonate environment took place in the Baoshan, Tengchong and Lhasa Block at the beginning of the Artinskian. The carbonate environment in the Baoshan Block was spoiled by the eruption of the Woniusi Basalts, and in the Xainza area of the Lhasa Block was shortly replaced by clastic environment until the Kungurian. In the northern Himalayas limestones began to occur in the Late Permian in a fluctuating manner.

关键词： Permian Gondwana-affinity post-glacial Yunnan Tibet

Hydroformylation of 1-Octene over Nanotubular TiO2-supported Amorphous Co-B Catalysts

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Chemical Research in Chinese Universities 2015年第5期31卷 851-857页

作者： shi yukun HU Xiaojing ZHU Baolin ZHANG Shoumin HUANG Weiping Department of Chemistry Collaborative Innovation Center of Chemical Science and Engineering The Key Laboratory of Advanced Energy Materials Chemistry Ministry of Education Tianjin Key Lab of Metal and Molecule-based Material Chemistry Nankai University Tianjin 300071 P. R. China

TiO2 nanotubes supported amorphous Co-B（Co-B/TNTs） catalyst was prepared via impregnation- chemical reduction procedure. The catalyst was characterized with transmission electron microscopy（TEM）, ammonia temperature-programmed desorption（NH3-TPD）, thermogravimetry-differential thermal analysis（TG-DTA）, Fourier transform infrared spectroscopy（FTIR） and Raman spectroscopy. The effects of temperature and ratio of CO to HE on the hydroformylation of 1-octene were studied. At an optimized reaction temperature（150 ℃） and volume ratio of CO to H2（2：1）, the conversion of 1-octene can reach 97.4% with a selectivity of 23.1% for total aldehydes and n/i-aldehyde molar ratio of 40：60. To obtain higher selectivity for linear aldehydes, Co-B/TNTs modified with triphenylphosphine for the hydroformylation of 1-octene were investigated. When molar ratio of P/Co was 4, the yield of total aldehydes was the highest（31.6%） with a good selectivity for linear product（n/i-aldehyde molar ratio was 70：30）. In recycle use, the Co-B/TNTs catalyst modified with triphenylphosphine could be reused five times without reducing the activity and selectivity obviously. For a comparative study, all the Co-B/TNTs to catalyze the hydroformylation of other olefins exhibited high conversion under the optimized conditions.

关键词： Hydroformylation TiO2 nanotubes Amorphous Co-B 1-Octene

How to Build a High-Resolution Digital Geological Timeline?

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Journal of Earth Science 2022年第6期33卷 1629-1632页

作者： Shuzhong Shen Junxuan Fan Xiangdong Wang Feifei Zhang yukun shi Shuhan Zhang State Key Laboratory for Mineral Deposits Research School of Earth Sciences and EngineeringFrontiers Science Center for Critical Earth Material CyclingNanjing UniversityNanjing210023China

1 QUESTION FORMULATION Time and space are the two basic axes to characterize the existence of matter. Without time, there would be no rate(“No dates, No rates”). The Earth has a history of approximately 4.5 billion years, leaving behind a myriad of geological records,and the geologic timeline is the only common language available to unravel the evolutionary history of the Earth.

关键词： approximate Resolution Earth

Carboniferous integrative stratigraphy,biotas,and paleogeographical evolution of the Qinghai-Tibetan Plateau and its surrounding areas

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Science China Earth Sciences 2024年第4期67卷 1071-1106页

作者： Keyi HU Xiangdong WANG Wenqi WANG Yingfan SONG Xunyan YE Lu LI yukun shi Sunrong YANG Ying LI State Key Laboratory for Mineral Deposits Research School of Earth Sciences and Engineering and Frontiers Science Center for Critical Earth Material CyclingNanjing UniversityNanjing 210023China

During the Carboniferous Period,the Qinghai-Tibetan Plateau and its surrounding areas were located in quite different paleogeographic positions with various sedimentary and biological *** is important to systematically compile and summarize the Carboniferous strata and biotas of the Qinghai-Tibetan Plateau and its surrounding areas,to establish an integrated stratigraphic framework for correlation,and to reconstruct the paleogeography for correctly understanding the breakup of the Gondwana Continent and the evolution of the Paleo-Tethys Ocean in the Late *** Carboniferous of the Qinghai-Tibetan Plateau and its surrounding areas can be subdivided into the Gondwanan,Cimmerian,and Tethyan *** Gondwanan-type Carboniferous are distributed in the North Himalayan,Kangmar-Lhunze,and Zanda-Zumba regions of the South Tibet Subprovince and northern India-Pakistan Area,where only the Mississippian is developed and the biota is of Gondwanan *** Cimmerian-type Carboniferous,which are found in the Baoshan,Tengchong,Coqen-Xainza,LhasaZayu,Nagqu-Biru,and South Qiangtang regions,as well as Shan-Thai and South Afghanistan-Pamir areas,also represent only the Mississippian strata,but their biota is characterized by mixed characters of European,South China,Australian,and North American *** Tethyan-type Carboniferous are distributed in the Tanggula Mountains,Hoh Xil-Bayanhar,ChamdoHengduanshan,Tiekelike,West Kunlun,Karakorum,East Kunlun-Central Qinling,and Qilian regions,where the Carboniferous succession is well developed,and the biota is of warm-water Tethyan *** biostratigraphical correlation of the Gondwanan-type and Cimmerian-type Carboniferous is based mainly on conodonts and additionally on brachiopods and rugose *** Mississippian of the Tethyan-type Carboniferous is correlated mainly by using rugose corals and brachiopods,whereas in the Pennsylvanian foraminifera(fusuline)and conodonts are regarded as primary fossil groups,subord

关键词： Qinghai-Tibetan Plateau Carboniferous Lithostratigraphy Biota Stratigraphic correlation

Association between ambient NO_(2) exposure and health status in a floating population:findings from 338 cities in China

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Frontiers of Environmental Science & Engineering 2024年第10期18卷 49-59页

作者： yukun shi Yang Zhao Guangcheng Wang Jikai Xia Luyang Wang Hongyu Lil Wenhui Gao shijia Yuan Ronghang Liul Surong Zhao Chunlei Han School of Public Health Binzhou Medical UniversityYantai 264003China School of Health Management Binzhou Medical UniversityYantai 264003China The George Institute for Global Health University of New South WalesSydneyNSW 2050Australia The George Institute for Global Health Beijing 100600China Department of Radiology Yantai Affiliated Hospital of Binzhou Medical UniversityYantai 264100China

Few studies investigated the effects of exposure to NO_(2) on health status in the Chinese floating *** present cross-sectional study evaluated the association of ambient NO_(2) with health status in a floating population in *** on 168961 floating individuals in 338 cities were obtained from the 2017 China Migrants Dynamic *** association between exposure to NO_(2) and self-related health(SRH)status was assessed by binary logistic regression analysis,both in the entire subject cohort and in subgroups assorted by socioeconomic levels and demographic *** robustness of the associations between NO_(2) exposure and health status was evaluated by sensitivity *** grade increment of annual average NO_(2) exposure was found to increase the risk of poor SRH by 2.4%in the floating population(odds ratio[OR]=1.024,95%confidence interval[CI]:1.011-1.038).When subgrouped by age,subjects in the floating population aged 31-49 years had the highest NO_(2) associated health risk(OR=1.036,95%CI:1.018-1.054).When subgrouped by per capita gross domestic product(PGDP),subjects in regions with mid-level PDGP had the highest NO_(2) associated SRH(OR=1.116,95%CI:1.091-1.i41).These findings indicated that exposure to NO_(2) increases the risk of poor SRH in the floating population,with individuals aged 31-49 years and those living in mid-level PGDP regions being more sensitive to the adverse effects of NO_(2).More effective strategies to reduce air pollution may improve the health status of the floatingpopulation in China.

关键词： Airpollution NO_(2) Floating population Health status China

Geological Panorama Database:Digitizing and Visualizingthe Geological Outcrops

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Acta Geologica Sinica(English Edition) 2019年第S01期93卷 11-13页

作者： DENG Yiying CHEN Dongyang FAN Junxuan shi yukun HOU Xudong YANG Jiao XU Wenxiang State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology and Center for Excellence in Life and PaleoenvironmentChinese Academy of SciencesNanjing 210008JiangsuChina University of Science and Technology of China Hefei 230026AnhuiChina Jiangsu Huohe Information Technology Co. LtdNanjing 210000JiangsuChina School of Earth Sciences and Engineering Nanjing UniversityNanjing 210023China

1 Introduction Geological outcrops or sections are the basis of geological ***,the traditional methods for presenting them are mainly photos which fall short of delivering a true visual sense (Deng et al.,2009;Hou et al.,2014).With the continuous development of image acquisition technology using single-lens reflex camera (SLR camera),image synthesis,large file storage and acquisition,panoramic visualization and network technology.

关键词： geological outcrops panorama database digitization visualization

Identification of life-history stages in fusulinid foraminifera

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Identification of life-history stages in fusulinid foraminif...