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Modern pollen assemblages from surface lake sediments in northwestern China and their importance as indicators of vegetation and climate

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Science China Earth Sciences 2015年第9期58卷 1643-1655页

作者： qin Feng zhao Yan LI Quan CAI MaoTang Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Nature Resources ResearchChinese Academy of Sciences

The modern pollen assemblages of surface lake sediments and topsoils in northwestern China were studied to understand the relationship of modem pollen data with contemporary vegetation and climate, and the differences between the pollen assem- blages of surface lake sediments and topsoils. The results show that Chenopodiaceae and Artemisia are dominant elements in the pollen assemblages of northwestern China. Additionally, Ephedra, Cyperaceae, Asteraceae, Poaceae, Picea, Pinus, and Betula are also important pollen taxa. Both pollen assemblages and principal component analysis indicate that pollen data from surface lake sediments and topsoils can be used to differentiate the main vegetation types of this region （desert, steppe, mead- ow and forest）. However, differences exist between modern pollen assemblages of the two types of sediments due to the dif- ferent relevant source areas of pollen and degrees of pollen preservation. For example, the larger relevant source area of sur- face lake sediment results in a higher abundance of Betula in pollen assemblage from surface lake sediment, whereas the ten- dency to disintegrate thin-walled pollen types in topsoil leads to a higher proportion of resistant pollen, such as Asteraceae. Linear regression analysis indicates that the Artemisia/Chenopodiaceae （A/C） ratio in pollen assemblages of surface lake sedi- ments can be used to indicate humidity changes in the study area. However, the A/C ratio in topsoils should be used carefully. Our results suggest that pollen data from surface lake sediments would be better references for interpreting the fossil pollen assemblages of lake cores or lacustrine profiles.

关键词： modern pollen assemblage surface lake sediment topsoil vegetation climate northwestern China

Long term effects of artificial rearing before weaning on the growth performance, ruminal microbiota and fermentation of fattening lambs

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Journal of Integrative Agriculture 2022年第4期21卷 1146-1160页

作者： HUANG Wen-qin CUI Kai HAN Yong CHAI Jian-min WANG Shi-qin LÜXiao-kang DIAO Qi-yu ZHANG nai-feng Institute of Feed Research Chinese Academy of Agricultural Sciences/Key Laboratory of Feed Biotechnology of the Ministry of Agriculture and Rural AffairsBeijing 100081P.R.China Guizhou Institute of Animal Husbandry and Veterinary Science Guizhou 550005P.R.China Department of Animal Science Division of AgricultureUniversity of ArkansasFayettevilleAR72701USA

Early life intervention is important to shape the gut microbiome profiles of adult animals due to the tremendous alteration of diet components. Nevertheless, there is still no unified understanding about its long-term effects in lambs. In this study, sixty 20-day-old lambs were assigned into ewe-rearing(ER) and artificial-rearing(AR) treatments to evaluate the effects of AR strategy on ruminal microbiota, fermentation, and morphology of pre-weaning lambs(from 20 to 60 days of age) and its long-term effects in the fattening stage(from 61 to 180 days of age). During the pre-weaning stage, ER lambs were breastfed and supplemented starter, while AR lambs were artificially fed with milk replacer and starter. During the fattening stage, all lambs in both treatments were fed with the same fattening diets. At 60, 120 and 180 days of age, 6 lambs from each group were slaughtered to collect rumen content and tissue samples. Compared with ER lambs, the dry matter feed intakes of AR lambs increased(P0.05), it was higher(P<0.05) in AR lambs compared with ER lambs at the fattening stage. The rumen keratin layer of AR lambs was thinner(P<0.05) than that of ER lambs. Along with lamb growth from 60 to 180 days of age, the differences in rumen bacterial diversity between AR and ER treatments grew more distinct(P<0.05). Compared with ER lambs, AR lambs increased(P<0.05) rumen bacteria abundance, such as phylum Spirochaetes and genus Treponema at 60 days of age, phylum Actinobacteria and genus Succiniclasticum at 120 days of age, and phylum Proteobacteria at 180 days of age, but decreased genus Selenomonas from 60 to 180 days of age, and Anaerovibrio at 180 days of age. In summary,

关键词： artificial rearing lamb rumen microbiome rumen fermentation growth

A metal nitride interlayer for long life lithium sulfur batteries

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Journal of Energy Chemistry 2019年第2期28卷 1-2页

作者： Jin-Lei qin Huiyou zhao Jia-Qi Huang Department of Materials Science and Engineering China University of Mining and Technology (Beijing) Advanced Research Institute of Multidisciplinary Science Beijing Institute of Technology CAS Key Laboratory of Carbon Materials Institute of Coal ChemistryChinese Academy of Sciences

With the growing concerns on global energy crisis and the greenhouse effect,the exploration on renewable energy and related emerging energy conversion and storage technologies are highly interested [1].Lithium sulfur (Li–S) battery system receives great attention for its high theoretical specific energy(2600 Wh/kg),which is deemed to be a promising candidate as next generation high energy density batteries [2].

关键词： Shuttle of polysulfides Interlayers Layered double hydroxides Composite separators Lithium sulfur batteries

A case-based method of selecting covariates for digital soil mapping

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Journal of Integrative Agriculture 2020年第8期19卷 2127-2136页

作者： LIANG Peng qin Cheng-zhi ZHU A-xing HOU Zhi-wei FAN nai-qing WANG Yi-jie State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101P.R.China University of Chinese Academy of Sciences Beijing 100049P.R.China Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application School of GeographyNanjing Normal UniversityNanjing 210097P.R.China Key Laboratory of Virtual Geographic Environment Ministry of EducationNanjing Normal UniversityNanjing 210023P.R.China Department of Geography University of Wisconsin-MadisonMadisonWI 53706USA

Selecting a proper set of covariates is one of the most important factors that influence the accuracy of digital soil mapping(DSM).The statistical or machine learning methods for selecting DSM covariates are not available for those situations with limited *** solve the problem,this paper proposed a case-based method which could formalize the covariate selection knowledge contained in practical DSM *** proposed method trained Random Forest(RF)classifiers with DSM cases extracted from the practical DSM applications and then used the trained classifiers to determine whether each one potential covariate should be used in a new DSM *** this study,we took topographic covariates as examples of covariates and extracted 191 DSM cases from 56 peer-reviewed journal articles to evaluate the performance of the proposed case-based method by Leave-One-Out cross *** with a novices’commonly-used way of selecting DSM covariates,the proposed case-based method improved more than 30%accuracy according to three quantitative evaluation indices(i.e.,recall,precision,and F1-score).The proposed method could be also applied to selecting the proper set of covariates for other similar geographical modeling domains,such as landslide susceptibility mapping,and species distribution modeling.

关键词： digital soil mapping covariates case-based reasoning Random Forest

New Bibenzyl and Phenanthrenedione from Dendrobium densiflorum

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Chinese Chemical Letters 2000年第8期11卷 705-706页

作者： Fan, CQ zhao, WM qin, GW Chinese Acad Sci Shanghai Inst Mat Med Shanghai 200031 Peoples R China

A new bibenzyl 1 and a new phenanthrenedione 2 were identified from the stems of Dendrobium densiflorum (Orchidaceae).

关键词： Dendrobium densiflorum Orchidaceae phenanthrenedione bibenzyl

Smart Manufacturing for the Oil Refining and Petrochemical Industry

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Engineering 2017年第2期3卷 179-182页

作者： Zhihong Yuan Weizhong qin Jinsong zhao Departrnent of Chemical Engineering Tsinghua University Beijing 100084 China China Petroleum and Chemical Corporation Jiujiang Company Jiujiang 332004 China

Smart manufacturing will transform the oil refining and petrochemical sector into a connected, information-driven environment. Using real-time and high-value support systems, smart manufacturing enables a coor-dinated and performance-oriented manufacturing enterprise that responds quickly to customer demandsand minimizes energy and material usage, while radically improving sustainability, productivity, innovation,and economic competitiveness. In this paper, several examples of the application of so-called ＂smart manu-facturing＂ for the petrochemical sector are demonstrated, such as the fault detection of a catalytic crackingunit driven by big data, advanced optimization for the planning and scheduling of oil refinery sites, andmore. Key scientific factors and challenges for the further smart manufacturing of chemical and petrochem-ical orocesses are identified.

关键词： Smart manufacturing Petrochemical Data-/information-driven environment

Analysis on small-earthquake composite fault plane solutions from 1961 to 1999 in Xinfengjiang reservoir area

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Acta Seismologica Sinica(English Edition) 2004年第3期17卷 287-295页

作者： GUO Gui-an(郭贵安) LIU Te-pei(刘特培) qin nai-gang(秦乃岗) CHEN Li-fen(陈丽芬) Shenzhen Seismostation Shenzhen 518003 China Earthquake Administration of Guangdong Province Guangzhou 510070 China Earthquake Administration of Guangdong Province Guangzhou 510070 China Earthquake Administration of Guangdong Province Guangzhou 510070 China

To understand the earthquake characteristics in Xinfengjiang (XFJ for short) reservoir area, we collected the small earthquakes occurred in the area from 1961 to 1999. We segmented this 40-year period, parted the research region and calculated the composite fault plane solution of each block, disscussed the effect characteristics of stress field of water pressure using Mohrs stress circle. The final result shows that the main rupture pattern was very different before and after the M = 6.1 main shock, changing from strike slip to normal rupture. The maximum principal stress axes of composite fault plane solutions are characterized by synchronous change with water level.

关键词： Xinfengjiang reservoir Mohrs stress circle focal mechanism CLC number: P315.3 Document code: A

Metal-Organic Framework-Based Solid Acid Materials for Biomass Upgrade

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Transactions of Tianjin University 2021年第6期27卷 434-449页

作者： Yutian qin Jun Guo Meiting zhao Tianjin Key Laboratory of Molecular Optoelectronic Sciences Institute of Molecular Aggregation ScienceTianjin UniversityTianjin 300072China School of Chemistry Tiangong UniversityTianjin 300387China

Biomass is a green and producible source of energy and ***,developing high-efficiency catalysts for biomass utilization and transformation is urgently ***-organic framework(MOF)-based solid acid materials have been considered as promising catalysts in biomass *** this review,we first introduce the genre of Lewis acid and Brønsted acid sites commonly generated in MOFs or MOF-based ***,the methods for the generation and adjustment of corresponding acid sites are ***,the catalytic applications of MOF-based solid acid materials in various biomass transformation reactions are summarized and ***,based on our personal insights,the challenges and outlook on the future development of MOF-based solid acid catalysts are *** hope that this review will provide an instructive roadmap for future research on MOFs and MOF-based composites for biomass transformation.

关键词： Metal-organic framework Solid acid Catalysis Biomass Glucose

Study on Viscosity Reducing and Oil Displacement Agent for Water-Flooding Heavy Oil Reservoir

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China Petroleum Processing & Petrochemical Technology 2022年第1期24卷 11-18页

作者： qin Bing zhao Lin Jiang Jianlin Research Institute of Petroleum Processing SINOPECBeijing 100083

In the process of water-flooding development of heavy oil reservoir,due to the high viscosity and oil-water mobility ratio of heavy oil,there are some problems such as poor fluidity,high residual oil saturation and low recovery efficiency,which seriously restrict the efficient development of heavy *** molecular structure characteristics of asphaltenes and resins in heavy oil were *** on the three most concerned properties of chemical agents,including the emulsification performance,the interface performance and the oil washing performance,three chemical oil displacement agents for heavy oil reservoirs were developed,and the structure of the chemical agents were characterized by high resolution mass *** performance evaluation of chemical agents and core displacement experiments show that there is no obvious correlation between the properties of chemical agents,including interfacial tension,emulsifying ability and oil washing *** heavy oil reservoirs,the emulsification and viscosity reduction performance of chemical agents was more important than the oil washing capacity,and the oil washing capacity was more important than the interface *** reduction performance was the key parameter of oil displacement agent suitable for heavy oil *** composite binary system consisting of the viscosity reducer and the polymer had better oil recovery than using viscosity reducer alone.

关键词： heavy oil viscosity reducer emulsion surfactant enhanced oil recovery