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Geochemical and Mineral Characteristics of Jurassic Volcanic Rocks from ODP Sites 304, 1149, and 801:Implications for Magmatic Evolution in the Northwest Pacific

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Acta Geologica Sinica(English Edition) 2018年第3期92卷 915-934页

作者： CHEN shuangshuang LIU Jiaqi Patrick RIOUAL GUO Zhengfu Key Laboratory of Cenozoic Geology and Environment Institute of Geology and Geophysics Chinese Academy of Sciences State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Institutions of Earth Science Chinese Academy of Sciences

The regular variations in magmatic activities along the Northwest Pacific plate have been little studied in spite of their importance. In this contribution, systematic analyses were conducted on tholeiitic basalts from three Ocean Drilling Program sites(Sites 304, 1149, and 801), including the petrographic features, major and trace elements, Nd isotopic compositions, and mineral structure and compositions of whole rocks. Volcanic rocks from Sites 304, 1149, and 801 belong to tholeiites and exhibit depleted light rare earth elements(LREE), large ion lithophile elemental contents(LILE), and relatively depleted Nd isotopic ratios(143Nd/144Nd=0.513139-0.513211), similar to those of normal mid-ocean ridge basalts(NMORB). Comprehensive data on mineral compositions, whole-rock geochemistry, and geochronology demonstrate that a regular variation trend exists in the north-south direction along the Northwest Pacific plate. The 143 Nd/144 Nd values(0.513139-0.513211) and trace-element ratios for whole rocks(Sm/Th=15.35-30.00; Zr/Hf=28.53-35.76; Zr/Y=2.58-3.67; Th/La=0.04-0.06; Th/Y=0.33-0.70), as well as the trace-element ratios(Zr/Hf, La/Yb, Ti/Zr) of clinopyroxenes from Sites 1149 and 801 tholeiites show larger variations compared to those from Site 304 tholeiites(143Nd/144Nd=0.513185-0.513195; Sm/Th=18.19-20.58; Zr/Hf=31.07-33.26; Zr/Y=2.62-3.03; Th/La=0.05-0.06; Th/Y=0.48-0.57). Mineral zoning textures were obvious in tholeiites from Sites 1149 and 801 but were rarely observed in Site *** regular features were likely attributed to the differences in the heterogeneity of the magma source,the process of magmatic evolution, the plate-spreading rate, and the effective and ineffective mixing.

关键词： tholeiite zoning texture Ocean Drilling Program plate spreading rate Northwest Pacific

Bimetallic Ni-Fe catalysts derived from layered double hydroxides for CO methanation from syngas

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Frontiers of Chemical Science and Engineering 2017年第4期11卷 613-623页

作者： Tang, Honggui Li, shuangshuang Gong, Dandan Guan, Yi Liu, Yuan Tianjin Univ Sch Chem Engn Dept Catalysis Sci & Technol Tianjin 300072 Peoples R China Tianjin Univ Sch Chem Engn Collaborat Innovat Ctr Chem Sci & Engn Tianjin Tianjin 300072 Peoples R China

Carbon deposition and sintering of active components such as nano particles are great challenges for Ni-based catalysts for CO methanation to generate synthetic natural gas from syngas. Facing the challenges, bimetallic catalysts with different Fe content derived from layered double hydroxide containing Ni, Fe, Mg, A1 elements were prepared by co-precipitation method. Nanoparticles of Ni-Fe alloy were supported on mixed oxides of aluminium and magnesium after calcination and reduction. The catalysts were characterized by Brunner- Emmett-Teller （BET）, x-ray diffraction, hydrogen tem- perature programmed reduction, inductively coupled plasma, x-ray photoelectron spectroscopy, transmission electron microscopy and thermogravimetric techniques, and their catalytic activity for CO methanation was investigated. The results show that the Ni-Fe alloy catalysts exhibit better catalytic performance than mono- metallic catalysts except for the Ni4Fe-red catalyst. The Ni2Fe-red catalyst shows the highest CO conversion （100% at 260-350 ~C）, as well as the highest CH4 selectivity （over 95% at 280-350 ~C）, owing to the formation of Ni-Fe alloy. In stability test, the Ni2Fe-red catalyst exhibits great improvement in both anti-sintering and resistance to carbon formation compared with the Ni0Fe-red catalyst. The strong interaction between Ni and Fe element in alloy and surface distribution of Fe element not only inhibits the sintering ofnanoparticles but restrains the formation of Ni clusters.

关键词： methanation layered double hydroxide bime-tal Ni-Fe alloy sintering carbon deposition

Slope Stability Analysis Based on Group Decision Theory and Fuzzy Comprehensive Evaluation

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Journal of Earth Science 2020年第6期31卷 1121-1132页

作者： Peng x.a xinli Hu shuangshuang Wu Chunye Ying Chang Liu Faculty of Engineering China University of GeosciencesWuhan 430074China

A slope stability evaluation method is proposed combining group decision theory,the analytic hierarchy process and fuzzy comprehensive *** index weight assignment of each evaluation element is determined by group decision theory and the analytic hierarchy process,and the membership degree of each indicator is determined based on fuzzy set *** to the weights and memberships,the membership degrees of the criterion layer are obtained by fuzzy operations to evaluate the slope *** results show that(1)the evaluation method comprehensively combines the effects of multiple factors on the slope stability,and the evaluation results are accurate;(2)the evaluation method can fully leverage the experience of the expert group and effectively avoid evaluation errors caused by the subjective bias of a single expert;(3)based on a group decision theory entropy model,this evaluation method can quantitatively evaluate the reliability of expert decisions and effectively improve the efficiency of expert group discussion;and(4)the evaluation method can transform the originally fuzzy and subjective slope stability evaluation into a quantitative evaluation.

关键词： group decision theory analytic hierarchy process fuzzy comprehensive evaluation slope stability

Development of land use transitions research in China

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Journal of Geographical Sciences 2020年第7期30卷 1195-1214页

作者： LONG Hualou QU Yi TU shuangshuang ZHANG Yingnan JIANG Yanfeng Key Laboratory of Regional Sustainable Development Modeling Institute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China School of Geography Geomatics and PlanningJiangsu Normal UniversityXuzhou 221116JiangsuChina Key Laboratory of Environment Change and Resources Use in Beibu Gulf Nanning Normal Universitythe Ministry of EducationNanning 530001China School of Geographical Sciences University of Nottingham NingboNingbo 315000ZhejiangChina

With the introduction of the concept of land use transition into China,related researches have been carried out extensively in the past two decades,which enrich the knowledge of land system *** paper describes the development of research on land use transitions in China from the perspectives of conceptual connotations,theoretical model,research methods,and research progress and *** the in-depth investigation of land use transitions,the concept and connotations of land use morphology are developed and encapsulated as two kinds,i.e.,dominant morphology and recessive *** dominant morphology refers to the land use structure of a certain region over a certain period of time,with features such as the quantity and spatial pattern of land use *** the recessive morphology includes the land use features in the aspects of quality,property rights,management mode,input,output and ***,the concept of land use transition is further developed,and the theoretical model of regional land use transitions is ***,three innovative integrated approaches to study land use transitions are put forward,i.e.,multidisciplinary research framework for recessive land use transition,transect and horizontal *** date,there have been 62 *** 166 *** on the topic of"land use transition"in *** 2002–2019,the National Natural Science Foundation of China has funded 48 research programs on the theme of"land use transition".As such,the Chinese scholars have adapted the concept derived from western literature to the situations and experiences in China.

关键词： land use morphology theoretical model multidisciplinary integration horizontal comparison rural restructuring rural vitalization land system science

The horizon of bone organoid: A perspective on constructionand application

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Bioactive Materials 2022年第12期7卷 15-25页

作者： shuangshuang Chen x.ao Chen Zhen Geng Jiacan Su Institute of Translational Medicine Shanghai UniversityShanghai200444China Department of Orthopaedics Trauma Changhai HospitalSecond Military Medical UniversityShanghai200433China

Bone defects repair and regeneration by various causes such as tumor resection, trauma, degeneration, etc. havealways been a key issue in the clinics. As one of the few organs that can regenerate after adulthood, bone itselfhas a strong regenerative ability. In recent decades, bone tissue engineering technology provides various types offunctional scaffold materials and seed cells for bone regeneration and repair, which significantly accelerates thespeed and quality of bone regeneration, and many clinical problems are gradually solved. However, the bonemetabolism mechanism is complicated, the research duration is long and difficult, which significantly restrictsthe progress of bone regeneration and repair research. Organoids as a new concept, which is built in vitro withthe help of tissue engineering technology based on biological theory, can simulate the complex biologicalfunctions of organs in vivo. Once proposed, it shows broad application prospects in the research of organdevelopment, drug screening, mechanism study, and so on. As a complex.and special organ, bone organoidconstruction itself is quite challenging. This review will introduce the characteristics of bone microenvironment,the concept of organoids, focus on the research progress of bone organoids, and propose the strategies for boneorganoid construction, study direction, and application prospects.

关键词： Bone organoid Bone regeneration Scaffold Disease models

Power and efficiency optimizations for an open cycle two-shaft gas turbine power plant

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Propulsion and Power Research 2023年第4期12卷 457-466页

作者： Lingen Chen Huijun Feng Yanlin Ge shuangshuang Shi Institute of Thermal Science and Power Engineering Wuhan Institute of TechnologyWuhan 430205China Hubei Provincial Engineering Technology Research Center of Green Chemical Equipment Wuhan 430205China School of Mechanical&Electrical Engineering Wuhan Institute of TechnologyWuhan 430205China

In finite-time thermodynamic analyses for various gas turbine cycles,there are two common models:one is closed-cycle model with thermal conductance optimization of heat exchangers,and another is open-cycle model with optimization of pressure drop(PD)*** of optimization also with searching optimal compressor pressure ratio(PR).This paper focuses on an open-cycle model.A two-shaft open-cycle gas turbine power plant(OCGTPP)is modeled in this *** of power output(PP)and thermal conversion efficiency(TCE)are deduced,and these performances are optimized by varying the relative PD and compressor *** results show that there exist the optimal values(0.32 and 14.0)of PD and PR which lead to double maximum dimensionless PP(1.75).There also exists an optimal value(0.38)of area allocation ratio which leads to maximum TCE(0.37).Moreover,the performances of three types of gas turbine cycles,such as one-shaft and two-shaft ones,are *** the relative pressure drop at the compressor inlet is small,the TCE of third cycle is the biggest one;when this pressure drop is large,the PP of second cycle is the biggest *** results herein can be applied to guide the preliminary designs of OCGTPPs.

关键词： Two-shaft gas turbine power plant Efficiency Power Area distribution Pressure drop Finite-time thermodynamics

Construction and initial analysis of five Fosmid libraries of mitochondrial genomes of cotton(Gossypium)

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Chinese Science Bulletin 2013年第36期58卷 4608-4615页

作者： LI shuangshuang LIU GuoZheng CHEN ZhiWen WANG YuMei LI PengBo HUA JinPing Department of Plant Genetics and Breeding College of Agronomy and Biotechnology/Key Laboratory of Crop Heterosis and Utilization of Ministry of Education/Beijing Key Laboratory of Crop Genetic Improvement China Agricultural University Institute of Cash Crops Hubei Academy of Agricultural Sciences Cotton Research Institute Shanxi Academy of Agricultural Sciences

Cotton(Gossypium)is an important crop providing textile fiber and edible *** gain the insights into mechanism of the cytoplasmic male sterility(CMS)inheritance,we constructed five fosmid libraries of mitochondrial genomes from mitotype of *** Brandegee.(one CMS line and its restorer),mitotype of *** L.(one CMS line and its maintainer),and *** *** numbers of the clones in these libraries ranged from 1152 to 2016 with an average insert size of 36.2 to 38.4 kb,equivalent to 70–119.3 *** libraries were screened with 28 markers derived from the conservative sequences and yielded 22,19,26,21,and 23 positive clones,*** positive clones were used to construct the physical map of *** *** line and *** *** that shared six syntenis regions.A total of 30 genes in nine clusters showed conservative and had high similarity with those in the mitochondrial genomes of cotton,Carica papaya,Cucurbita pepo and Nicotiana *** investigation indicated that gene rrn26 had two copies in all five cotton mitogenomes,while genes atp1,rrn5 and rrn18 had two copies only in *** *** positive clones and physical map are considered being useful resources in cotton genomics research.

关键词：线粒体基因组粘粒文库棉花细胞质雄性不育系阳性克隆 CMS系保守序列物理图谱

Tuning of activated sludge in winter based on respirogram profiles under standard and site temperatures

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Journal of Environmental Sciences 2019年第5期31卷 330-338页

作者： Zhihua Li Zhenyu Hang Qian Zhang shuangshuang Zhang Tianyu Zhang Hanqing Yu School of Environmental and Municipal Engineering Xi'an University of Architecture and Technology Department of Mathematical Sciences Montana State University CAS Key Laboratory of Urban Pollutant Conversion Department of Chemistry University of Science & Technology of China

Respirograms of activated sludge OUR_ x^Tand OUR_x^(20)were measured under site(T) and standard(20°C) temperatures, respectively, and the predicted standard temperature respirogram OUR_( x,cal)^(20)was also calculated using the Arrhenius equation. These respirogram profiles reveal more information than effluent quality. A decrease of OUR_ x ^(20)is a critical alarm signal for the loss of pollutant removal capacity, and a sudden increase of the predicted value OUR_( x,cal)^(20)is an alarm signal for the unrecoverable deterioration of biomass. The sign of OUR_x^(20)–OUR_(x,cal)^(20)can be used for selection of tuning strategies. For example, a negative value of OUR_x^(20)–OUR_( x,cal)^(20)indicates that doubling biomass is difficult,thus strategies such as extending the reaction time with limited available biomass is preferred. The findings in this study elucidated the respiration profile of activated sludge under changes of temperature and can be effectively used for the stable operation of Wastewater Treatment Plants under cold temperatures and seasonal variations.

关键词： Activated sludge Cold temperature shocking Oxygen uptake rate(OUR) Respirogram Seasonal variations

Development of cryptotanshinone-loaded pellets for angina chronotherapy:In vitro/in vivo prediction and evaluation

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Asian Journal of Pharmaceutical Sciences 2018年第4期13卷 310-316页

作者： Zhenghua Li shuangshuang Zhang Hongx.ang Yan Jianping Liu Department of Pharmaceutics China Pharmaceutical University

The clinical manifestations of variant angina is unevenly distributed during the 24 h, thusthe in vivo performance of drugs should be tailored according to the angina circadianrhythm. Cryptotanshinone(CTN) is one of the representative bioactive lipid-soluble com-ponents of Danshen which has been commonly used for cardiovascular diseases such asangina pectoris. The aim of this study was to develop a novel CTN sustained-released pel-lets(CTN-SRPs) to precisely synchronize the CTN plasma concentrations with predictedoccurrence of angina pectoris for angina chronotherapy. A deconvolution-based methodwas applied to develop and optimize the CTN-SRPs. The plasma concentration-time curveof CTN immediate-released formulation after oral administration in rats was used as theweight function. The predicted plasma concentration-time curve of CTN-SRPs simulatedaccording to the incidence of variant angina during 24 h was used as the response func-tion. Then the desired drug release profile of CTN-SRPs was calculated based on deconvo-lution using weight function and response function, and subsequently used for guiding theformulation optimization. CTN-SRPs were prepared with the combinations of PVP, polox.amer 127 and EC as matrix using fluidized bed technology. An orthogonal design was em-ployed to obtain the optimal formulation with its release profile similar with the desiredone. Pharmacokinetic studies validated that the actual plasma concentration-time curve ofthese optimized CTN-SRPs was similar with the predicted one. In addition, the percent er-rors(%PE) of CTN plasma concentrations in 8–12 h were less than 10%. In conclusion, thisdeconvolution-based method could be applied to adjust the in vivo performance of drugs forangina chronotherapy.

关键词： Chronotherapy Deconvolution Angina pectoris Cryptotanshinone In vitro/in vivo performance Control release