检索结果-南通市图书馆

Geochemistry of high-Mg andesites from the early Cretaceous Yixian Formation, western Liaoning: Implications for lower crustal delamination and Sr/Y variations

引用

science China Earth sciences 2006年第9期49卷 904-914页

作者： WANG Xiaorui1, GAO Shan1,2, LIU Xiaoming1, YUAN Honglin1, HU Zhaochu1, ZHANG Hong1,3 & WANG Xuance4.1. State Key Laboratory of Continental Dynamics, department of Geology, Northwest University, Xi`an 710069, China 2. State Key Laboratory of geological Processes and Mineral Resources, China University of Geosciences, Wuhan 4.0074. China 3. Shenyang Institute of Geology and Mineral Resources, Shenyang 110032, China 4. Guangzhou Institute of Geochemistry, Chinese Academy of sciences, Guangzhou 51064., China 1. State Key Laboratory of Continental Dynamics Department of Geology Northwest University Xi’an 710069 China 2. State Key Laboratory of geological Processes and Mineral Resources China University of Geosciences Wuhan 430074 China 3. Shenyang Institute of Geology and Mineral Resources Shenyang 110032 China 4. Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China

85 volcanic rocks of the Yixian Formation from the Sihetun type section werecollected and analyzed for geochemical and isotopic compositions. Major element compositionsindicate that the Sihetun volcanic rocks are high magnesium andesites with some basalts occurring atthe bottom of section. The Sihetun high magnesium andesites (SiO_2 = 52.82-59.31 wt%, Al_2O_3=14.15-16.35wt%) show many characteristics of adakites such as depletion in heavy rare-earth elements(HREE; Yb = 1.03-1.88 μg/g) and Y(12-20 μg/g) and high Sr (620-1323 μg/g) and Sr/Y(32-88), withhigh La_N/Yb_N ratio (10-25). They share similar major and trace element characteristics to volcanicrocks from the Xinglonggou Formation except their lower Nd isotope ratios (^(14.)Nd/^(14.)Nd(130Ma) = 0.5118-0.5119, ε_(Nd) (130Ma) = -11.6-13.8, ^(87)Sr/^(86)Sr (130 Ma) = *** were interpreted in a way that eclogite that formed at the base of thickened Archean lowercrust of the North China craton foundered into the convecting mantle and subsequently melted andinteracted with peridotite. However, compared to the Xinglonggou volcanic rocks, the source of theSihetun magma contained more ancient continental crustal material in order to explain its evolved Ndisotopes. The age of the Sihetun Formation was 120 to 130 Ma, and this indicates that delaminationlasted to the early Cretaceous period. The Sr contents and Sr/Y ratios of the Sihetun high-Mgandesites show significant negative correlations with SiO_2 for samples with SiO_2 > 56%. Thesesuggest that the Sr and Sr/Y values were reduced due to fractional crystallization of ***, the effect of crystallization on volcanic Sr and Sr/Y ratio has to be taken intoaccount.

关键词： High-Mg andesite, Adakite, Yixian Formation, North China Craton, delamination.

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Distributions of fatty acids in a stalagmite related to paleoclimate change at Qingjiang in Hubei,southern China

引用

science China Earth sciences 2005年第9期48卷 1463-1469页

作者： XIE Shucheng1,HUANG Junhua1,WANG Hongmei2,YI Yi1,HU Chaoyong1, CAI Yanjun3 & CHENG Hai4.1. Faculty of Earth science,China University of Geosciences,Wuhan 4.0074.China 2. School of Environmental Studies,China University of Geosciences,Wuhan 4.0074.China 3. SKLLQG,Institute of Earth Environment,Chinese Academy of sciences,Xi’an 710075,China 4. {4. of Geology and Geophysics,University of Minnesota,MN554.5,usa 1. Faculty of Earth science China University of Geosciences 430074 Wuhan China 2. School of Environmental Studies China University of Geosciences 430074 Wuhan China 3. SKLLQG Institute of Earth Environment Chinese Academy of Sciences 710075 Xi’an China 4. department of Geology and Geophysics University of Minnesota 55455 MN USA

Fatty acids extracted from a subtropical stalagmite at Qingjiang in Southern China’s Hubei Province were analysed using gas chromatography-mass spectrometry. These n-alkanoic acids range from C14.to C26 in carbon number, maximizing at C16, with a second dominance at C22. In contrast to the stalagmite analysed, the overlying soils are characterized by the dominance of heavy-molecular-weight homologues (>C20). The n-fatty acids in the stalagmite were proposed to be contributed by both the soil ecosystems and the microbes harboring in the percolating water and the cave. The ratios of unsaturated to saturated n-fatty acids (C16:1i/C16:0, C18:1/C18:0) appear to show trends comparable with the oxygen isotope records of the stalagmite carbonate, with enhanced values associated with the cold episode such as Heinrich event 1. This paleoclimate-dependent record of the n-fatty acids might reflect microbial changes in physiology and activity in response to the temperature. This record shows somewhat difference from the previous paleoclimate signal extracted from n-alkanols and n-alkan-2-ones of the same stalagmite. The acid record fails to document the well-known Younger Dryas event which was effectively shown by the latter two biomarkers derived from soil ecosystems. This discrepancy might result from the changing biogeochemical impact on different lipid fractions as well as the varied organism populations in different ecosystems.

关键词： biomarker, ecosystem, microbe, speleothem, paleoclimate, Quaternary.

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Experimental and computational optimization of Prussian blue analogues as high-performance cathodes for sodium-ion batteries:A review

引用

Journal of Energy Chemistry 2024年第6期93卷 627-662,I0015页

作者： Gwangeon oh Junghoon Kim Shivam Kansara Hyokyeong Kang Hun-Gi Jung Yang-Kook Sun Jang-Yeon Hwang department of Energy Engineering Hanyang UniversitySeoul 04763Republic of Korea Energy Storage Research Center Clean Energy Research DivisionKorea Institute of Science and TechnologySeoul 02792Republic of Korea department of Energy science Sungkyunkwan UniversitySuwon 16419Republic of Korea KIST-SKKU Carbon-Neutral Research Center Sungkyunkwan UniversitySuwon 16419Republic of Korea department of Battery Engineering Hanyang UniversitySeoul 04763Republic of Korea

In this review,we discuss the electrochemical properties of Prussian blue(PB)for Na^(+)storage by combining structural engineering and electrolyte *** integrated experimental data and density functional theory(DFT)in sodium-ion battery(SIB)research to refine the atomic arrangements and crystal lattices and introduce substitutions and *** changes affect the lattice stability,intercalation,electronic and ionic conductivities,and electrochemical *** unraveled the intricate structure-electrochemical behavior relationship by combining experimental data with computational models,including first-principles *** holistic approach identified techniques for optimizing PB and Prussian blue analog(PBA)structu ral properties for *** also discuss the tuning of electrolytes by systematically adjusting their composition,concentration,and additives using a combination of molecular dynamics(MD)simulations and DFT *** review offers a comprehensive assessment of strategies for enhancing the electrochemical properties of PB and PBAs through structural engineering and electrolyte modifications,combining experimental insights with advanced computational simulations,and paving the way for next-generation energy storage systems.

关键词： Prussian blue analogs(PBAs) Sodium ion batteries(SIBs) Structural engineering Electrolyte modifications Experiments Density functional theory(DFT)

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Electrokinetic-mechanism of water and furfural oxidation on pulsed laser-interlaced Cu_(2)O and CoO on nickel foam

引用

Journal of Energy Chemistry 2024年第4期91卷 145-154页

作者： Yewon oh Jayaraman Theerthagiri M.L.Aruna Kumari Ahreum Min Cheol Joo Moon Myong Yong Choi department of Chemistry(BK21 FOUR) Research Institute of Natural SciencesGyeongsang National UniversityJinju 52828Republic of Korea department of Chemistry The Oxford College of ScienceBengaluruKarnataka 560102India Core-Facility Center for Photochemistry&Nanomaterials Gyeongsang National UniversityJinju 52828Republic of Korea

The electrocatalytic oxidation of biomass-derived furfural(FF)feedstocks into 2-furoic acid(FA)holds immense industrial potential in optics,cosmetics,polymers,and ***,we fabricated Co O/Ni O/nickel foam(NF)and Cu_(2)O/Ni O/NF electrodes via in situ pulsed laser irradiation in liquids(PLIL)for the bifunctional electrocatalysis of oxygen evolution reaction(OER)and furfural oxidation reaction(FOR),*** oxidation of NF surface to NiO and deposition of CoO and/or Cu_(2)O on NF during PLIL offer distinct advantages for enhancing both the OER and ***/NiO/NF electrocatalyst provides a consistently low overpotential of~359 m V(OER)at 10 m A/cm^(2),achieving the maximum FA yield(~16.37 m M)with 61.5%selectivity,79.5%carbon balance,and a remarkable Faradaic efficiency of~90.1%during 2 h of FOR at 1.4. V(*** hydrogen electrode).Mechanistic pathway via in situ electrochemical-Raman spectroscopy on CoO/NiO/NF reveals the involvement of phase transition intermediates(NiOoh and CoOoh)as surface-active centers during electrochemical *** carbonyl carbon in FF is attacked by hydroxyl groups to form unstable hydrates that subsequently undergo further oxidation to yield FA *** method holds promise for large-scale applications,enabling simultaneous production of renewable building materials and fuel.

关键词： Pulsed laser irradiation in liquids Water and furfural oxidation In situ Raman spectroscopy CoO/NiO/nickel foam Cu_(2)O/Nio/nickel foam 2-furoic acid

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Implementation of a multiple round quantum dense coding using nuclear magnetic resonance

引用

science China(Physics,Mechanics & Astronomy) 2005年第6期48卷 706-715页

作者： ZHANG Jingfu1, XIE Jingyi2, WANG Chuan1, DENG Zhiwei3, LU Zhiheng4. & LONG Guilu1,5 1. Key Laboratory For Quantum Information and Measurements of MOE, department of Physics, Tsinghua University, Beijing 100084.China 2. department of Materials science and Engineering, Beijing Normal University, Beijing 100875, China 3. Testing and Analytical Center, Beijing Normal University, Beijing 100875,China 4. department of Physics, Beijing Normal University, Beijing 100875, China 5. Key Laboratory For atomic and Molecular Nanosciences, Tsinghua University, Beijing 100084.China 1. Key Laboratory For Quantum Information and Measurements of MOE Department of Physics Tsinghua University 100084 Beijing China 2. department of Materials science and Engineering Beijing Normal University 100875 Beijing China 3. Testing and Analytical Center Beijing Normal University 100875 Beijing China 4. department of Physics Beijing Normal University 100875 Beijing China 5. Key Laboratory For Atomic and Molecular Nanosciences Tsinghua University 100084 Beijing China

A multiple round quantum dense coding scheme based on the quantum phase estimation algorithm is proposed and implemented in a three qubit nuclear magnetic resonance (NMR) quantum computer. Using an m + 1 qubit system, Bob can transmit one of 2m+1 messages to Alice, through manipulating only one qubit and exchanging it between Alice and Bob for m rounds. The information capacity is enhanced to m + 1 bits as compared to m bits in a classical scheme. The scheme has been demonstrated in NMR system, and the experimental results show a good agreement between theory and experiment.

关键词： quantum dense coding, multiple round, nuclear magnetic resorance

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Theoretical study on the reaction mechanism of(CH_3)_3CO+CO

引用

science China Chemistry 2005年第1期48卷 18-24页

作者： ZHAO Hongmei1,2,3, SUN Chengke1,4. ZHANG Rongchang3, XI Hongmin3 & LI Zonghe1 1. department of Chemistry, Beijing Normal University, Beijing 100875, China 2. The Laboratory of Molecular Reaction Dynamics, Institute of Chemistry, Chinese Academy of sciences, Beijing 100080, China 3. department of Chemistry, Beihua University, Jilin 132013, China 4. department of Chemistry, Qujing Normal University, Yunnan 655000, China 1. department of Chemistry Beijing Normal University 100875 Beijing China 2. The Laboratory of Molecular Reaction Dynamics Institute of Chemistry Chinese Academy of Sciences 100080 Beijing China 3. department of Chemistry Beihua University 132013 Jilin China 4. department of Chemistry Qujing Normal University 655000 Yunnan China

The reaction mechanism of (CH3)3CO with CO has been theoretically investigated using density-functional theory (DFT) calculations at B3LYP/6-31G* level. In order to get more reliable energy values the single-point energy is evaluated at CCSD (T)/6-31++G** level. The results show that the reaction is multi-channel and the reaction of (CH3)3CO radical with CO mostly produces (CH3)3C + CO2. The reaction could play a role in eliminating air pollution.

关键词： DFT, B3LYP, (CH3)3CO, radical.

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Inhibition of ethanol-induced toxicity by tanshinone ⅡA in PC12 cells

引用

Acta Pharmacologica Sinica 2006年第6期27卷 659-664页

作者： Xian-fang MENG~2 Xiao-jing ZOU~3 Bin PENG~2 Jing SHI~2 Xin-min GUAN~2 Chun ZHANG~(4.5)2 department of Neurobiology,Tongji Medical College,Huazhong University of science and Technology,Wuhan 4.0030,China 3 department of Anesthesiology,4.department of Nephrology,Union Hospital,Tongji Medical College,Huazhong University of science and Technology,Wuhan 4.0022.China department of Neurobiology Tongji Medical College Huazhong University of Science and Technology Wuhan China department of Anesthesiology Union Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan China department of Nephrology Union Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan China

Aim:To observe the effects of tanshinone IIA(Tan IIA)on the neurotoxicityinduced by ethanol in PC 12 cells and to explore its protective ***:PC 12cell survival was measured by MTT *** formation of reactive oxygenspecies(ROS)and lactate dehydrogenase(LDH)release were detected by 2′,7′-dichlorofluorescin(DCF)fluorescence and calorimetric method,*** of cell apoptosis was monitored by flow *** expression ofp53 was detected by immuno-fluorescence and flow ***:Ethanolsignificantly impaired the survival of PC12 cells as demonstrated by MTT *** also induced significant ROS formation and increased LDH ***-incubation with Tan IIA in the culture medium significantly reversed these *** caused cell apoptosis and the upregulation of p53 *** anti-apoptosis effects of Tan IIA on ethanol-induced toxicity were accompanied by thedownregulation of pro-apoptotic p53 protein ***:Tan IIAcan protect neurons from apoptosis and might serve as a potential therapeuticdrug for neurological disorders induced by ethanol.

关键词： apoptosis ethanol PC12 cells p53 tanshinone ⅡA

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Anticoagulation property and security of artificial heart valve material

引用

science China(Technological sciences) 2005年第2期48卷 145-162页

作者： WANG Xianghui1, , LIU Xianghuai1,22, 3, ZHANG Feng2, LI Changrong2, YU Liujiang2, ZHENG Zhihong2, WANG Xi2, JIANG Zhenbin4. CHEN Anqing4.& XU Jingfang3 1. department of Physics, East China Normal University, Shanghai 200062, China 2. Ion Beam Lab, Shanghai Institute of Mini-system and information, Chinese Academy of sciences,Shanghai 200050, China 3. department of Electronics, School of Information science and Technology, East China Normal Univer- sity, Shanghai 200062, China 4. Shanghai Cardiovascular Institute, Zhongshan Hospital, Shanghai 200032, China 1. department of Physics East China Normal University 200062 Shanghai China 2. Ion Beam Lab Shanghai Institute of Mini-system and information Chinese Academy of Sciences 200050 Shanghai China 3. department of Electronics School of Information Science and Technology East China Normal University 200062 Shanghai China 4. Shanghai Cardiovascular Institute Zhongshan Hospital 200032 Shanghai China

Heart valve diseases threaten human health. One reliable way to save lives of such patients is to replace the pathologically changed heart valves by artificial ones. Over 2 million patients have received LTI-carbon heart valve’s implantation. However, the thrombosis after the implantation is one of the difficulties that need to be solved. In order to improve the blood compatibility and security of mechanical heart valves, ion beam technology was used to modify the surface properties of the materials. The investigation results have been summarized in this paper.

关键词： artificial heart valve, ion implantation, plasma immersed ion implantation, ion beam enhanced deposition.

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Large second-order optical nonlinearities of s-triazine derivatives: View from micro molecules to macro crystals

引用

science China Chemistry 2005年第3期48卷 203-209页

作者： FANG Qi1, LEI Hong2, CUI Yuezhi3, HUANG Zhenli4. XUE Gang1 & YU Wentao1 1. State Key Laboratory of Crystal Materials, Shandong University, Jinan 250100, China 2. School of Information science and Engineering, Shandong University, Jinan 250100, China 3. department of Chemical Engineering, Light Industry College of Shandong, Jinan 250100, China 4. Key Laboratory of Biomedical Photonics, Ministry of Education, Huazhong University of science and Technology, Wuhan 4.0074. China 1. State Key Laboratory of Crystal Materials Shandong University 250100 Jinan China 2. School of Information science and Engineering Shandong University 250100 Jinan China 3. department of Chemical Engineering Light Industry College of Shandong 250100 Jinan China 4. Key Laboratory of Biomedical Photonics Ministry of Education Huazhong University of Science and Technology 430074 Wuhan China

Three s-triazine derivatives have been synthesized and their structures been de-termined. These are Compound I: 2,4.dimethyl-6-(p-N,N-dimethylaminostyryl)-s-triazine (abbre-viated to NMe-1), Compound II: 2,4.dimethyl-6-(p-N,N-diethylaminostyryl)-s-triazine (to NEt-1), and Compound III: 2-methyl-4.6-bis(p-N,N-dimethylaminostyryl)-s-triazine (NMe-2). NMe-1 and NEt-1 molecules belong to the D-π-A type with a one-dimensional charge-transfer character. NMe-1 crystallizes to centrosymmetric P1 space group, while NEt-1 to non-centrosymmetric polar Cc space group with all of the molecular charge-transfer axes taking the same orientation. Under the irradiation of 1064.nm fundamental laser, NEt-1 powder crystals radiate a 2-order harmonic light with an intensity 4..8 times that of urea. The Λ typed NMe-2 molecule, which has a two-dimensional charge-transfer character, crystallizes to polar P21 space group. Its powder crystals exhibit a 2-order harmonic intensity 4..2 times that of urea. The quantum chemical cal-culations and tensor analyses have been carried out to reveal the dependence of the macro 2-order nonlinear optical (NLO) efficiency on the micro 2-order NLO coefficients (β) and on the crystalline packing styles.

关键词： s-triazine derivatives, synthesis, structure, SHG intensities of crystals, βvalues of molecules.

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Application of backflush and micro-flow techniques to the analysis of C5—C13 hydrocarbons in crude oils and its geochemical significance

引用

Progress in Natural science:Materials International 2007年第11期17卷 1382-1387页

作者： Wang Peirong1,2, Zhao Hong2,3, Xu Guanjun1,4. Zhu Cuishan2,3, Xiao Tingrong4. Zhang Min2,3 and Zhang Bin1,4.1. Key Laboratory of Petroleum Geochemistry, China National Petroleum Corporation, Beijing 100083, China 2. Geochemistry department of Yangtze University, Jingzhou 4.4.23, China 3. Key Laboratory of Exploration Technologies for Oil and Gas Resources, Ministry of Education, Yangtze University, Jingzhou 4.4.23, China 4. Petroleum Geology Central Laboratory, Research Institute of Petroleum Exploration and Development, PetroChina, Beijing 100083, China) Key Laboratory of Petroleum Geochemistry China National Petroleum Corporation Beijing 100083 China Geochemistry department of Yangtze University Jingzhou 434023 China Key Laboratory of Exploration Technologies for Oil and Gas Resources Ministry of Education Yangtze University Jingzhou 434023 China Petroleum Geology Central Laboratory Research Institute of Petroleum Exploration and Development PetroChina Beijing 100083 China

An Agilent 6890N GC equipped with both FID and Agilent 5975 MSD analyzer has been employed to analyze C5—C13 hydrocarbon fractions of crude oils. A technical combination of program temperature volatilizer injection, backflush and micro-flow controller afforded a fine separation of C5—C13 compounds on a PONA column with the heavy part of crude oils being cut off before entering the analytical column. Both GC-FID chromatogram and GC-MS mass chromatograms (MID and full scan) could be obtained at the same time. The retension time differences of nC6—nC13 alkanes between GC and TIC were in the range of 0.02—0.58 minutes. Totally 286 peaks have been assigned group compositions. Results on 8 typical oil samples from CNPC Key Laboratory Crude Oil Library showed that the characteristics of C6—C13 hydrocarbon group composition could be used in oil-oil correlation studies.

关键词： GC analysis GC/MS analysis backflush micro-flow controller light fraction in crude oil

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：