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Constraints of authigenic carbonates on trace elements (Sr,Mg) of lacustrine ostracod shells in paleoenviron-ment reconstruction and its mechanism

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science china Earth sciences 2008年第5期51卷 654-664页

作者： HU Guang1,2, JIN ZhangDong1 & ZHANG Fei3 1 State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of sciences, Xi’an 710075, china 2 Graduate university of the Chinese Academy of sciences, Beijing 100049, china 3 College of Resources and Environmental science, Nanjing agricultural university, Nanjing 210095, china State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi’an 710075 China Graduate university of the Chinese Academy of sciences Beijing 100049 China College of Resources and Env

Molar ratios of Mg/Ca and Sr/Ca were measured in two species of ostracod shells preserved in the upper core (15–55 m) of the Hequing Basin in yunnan Province, southwest china. By correlating the molar ratios between Mg/Ca and Sr/Ca and comparing them with Sr concentrations of the sediments, we suggested that: (1) the molar Mg/Ca and Sr/Ca ratio variations in respective ostracod primo reflected the changes in its ambient water composition and ecology; (2) the molar Sr/Ca ratios responded better to the salinity change linearly than Mg/Ca without aragonite precipitation in the system, and otherwise there was no linear relation between them; and (3) the molar Sr/Ca ratios were mainly controlled by salinity and authigenic carbonate precipitation, whereas the molar Mg/Ca ratios were related to both salinity and temperature. In fact, the rate of ostracod growth owing to temperature controls the fluctuation of Mg/Ca in shells. Here, more attentions should be paid to the constraint of authigenic mineral precipitation processes on the trace elements in ostracod shells and to the correlation between these trace elements in biogenic carbonates and compositions of the sediments in systems and in future in vitro experiments.

关键词： ostracod shell molar Sr/Ca ratio molar Mg/Ca ratio environmental response Heqing Basin

Hydrothermal Synthesis,Crystal Structure and Properties of Inorganic-Organic Hybrid Materials Based on Diphosphopentamolybdate

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Journal of Wuhan university of technology(Materials science) 2008年第3期23卷 407-410页

作者：靳素荣 School of science Wuhan University of Technology

The compound of diphosphopentamolybdate { [Cu（en）（Hen）]2[P2Mo5O23] }·3H2O [en=ethylenediamine] had been obtained from the hydrothermal method and characterized by single crystal X-ray diffraction, elemental analysis, FT-IR, and thermogravimetric analysis The structure consist of [P2Mo5O23]^6- clusters anions, complex [Cu（en）（Hen）]^3＋ cations and crystallization water molecules, which are held together to a two-dimensional framework The most interesting feature of the compound is that two nitrogen atoms are both coordinated with Cu（ Ⅱ ） in one ethylenediamine molecule, for the other ethylenediamine molecule, only one nitrogen atom is towards Cu（ Ⅱ） and the other nitrogen atom is protonated and formed Hen^＋.

关键词： polyoxometalate hydrothermal synthesis crystal structure coordination groups

Search for B_c (ns) via the B_c (ns) → B_c (ms) π^+ π^- transition at LHCb and Z^0 factory

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science china(Physics,Mechanics & Astronomy) 2010年第11期53卷 2019-2024页

作者： KE HongWei 1 & LI XueQian 2 1 School of science,Tianjin university,Tianjin 300072,china 2 School of Physics,Nankai university,Tianjin 300071,china 1. School of science Tianjin University Tianjin 300072 China2. School of Physics Nankai University Tianjin 300071 China

It is interesting to study the characteristics of the whole family of B c which contains two different heavy *** and the proposed Z 0 factory provide an opportunity because a large database of the B c family will be achieved.B c and its excited states can be identified via their decay *** suggested by experimentalists,B-c (ns) → B c +γ is not easy to be clearly measured,instead,the trajectories of π + and π- occurring in the decay of B c (ns) → B c (ms) + π + π( n > m ) can be unambiguously identified,thus the measurement seems easier and more reliable;therefore this mode is more favorable at the early running stage of LHCb and the proposed Z 0 *** this work,we calculate the rate of B c (ns) → B c (ms) + π + π-in terms of the QCD multipole-expansion and the numerical results indicate that the experimental measurements with the luminosity of LHC and Z 0 factory are feasible.

关键词： meson hadronic decay QCD multipole-expansion

A membrane-tethered transcription factor ANAC089 negatively regulates floral initiation in Arabidopsis thaliana

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science china(Life sciences) 2010年第11期53卷 1299-1306页

作者： LI JianQin1,2, ZHANG Juan1, WANG XueChen1 & CHEN Jia1 1 State Key Laboratory of Plant Physiology and Biochemistry,College of Biological sciences, china agricultural university, Beijing 100193, china 2 College of Life science and technology, Guangxi university, Nanning 530005, china 1. State Key Laboratory of Plant Physiology and Biochemistry College of Biological Sciences China Agricultural University Beijing 100193 China2. College of Life Science and Technology Guangxi University Nanning 530005 China

The plant-specific NAC (NAM, ATAF1/2,and CUC2) transcription factors have a regulatory function in developmental processes and stress responses. Notably a group of NAC members named NTLs (NTM1-Like) are membrane-tethered, ensuring plants rapidly respond to developmental changes and environmental stimuli. Our results indicated that ANAC089 was a membrane-tethered transcription factor and its truncated form was responsible for the physiological function in flowering time control.

关键词： Arabidopsis thaliana ANAC089 floral initiation membrane-tethered transcription factor

EFFECT OF NITROGEN ON MATRIX STRUCTURE OF GRAY CAST IRON

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Acta Metallurgica Sinica(English Letters) 1993年第6期6卷 370-372页

作者： ZHAI Qijie HU Hanqi university of science and technology Beijing,china associate professor,faculty of Foundry,university of science and technology Beijing,Beijing 100083,china

Effect of nitrogen on matrix structure of 3 different varieties of gray cast iron,i.e., sub-eutectic Fe-C-Si,near-eutectic Fe-C-Si and Fe-C-Si-Mn,has been investigated. The eutectie colony structure of gray cast iron may be refined,the pearlite content increased and the micro-hardness of pearlite and ferrite raised with an addition of *** influ- ence of nitrogen on the transformation temperature of the equilibrium and non-equilibrium phases,as well as,the solution of nitrogen in ferrite and cementite seem to be the major rea- sons to strengthening the matrix structure of gray cast iron.

关键词： nitrogen gray cast iron matrix structure microhardness solid solution

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衰老或肿瘤：癌基因诱导的双向性

生物化学与生物物理进展 2009年第12期36卷 1530-1535页

作者：司晓宇罗瑛昆明理工大学生命科学与技术学院、衰老与肿瘤分子遗传学实验室昆明650224

在大部分的肿瘤中都发现有癌基因的活化,癌基因的活化被认为是导致肿瘤发生的重要原因.然而,在野生型细胞内,癌基因的活化可以诱导细胞衰老,称为癌基因诱导的细胞衰老(oncogene-induced senescence,OIS),从而抑制进一步的肿瘤发生.因而... 详细信息

在大部分的肿瘤中都发现有癌基因的活化,癌基因的活化被认为是导致肿瘤发生的重要原因.然而,在野生型细胞内,癌基因的活化可以诱导细胞衰老,称为癌基因诱导的细胞衰老(oncogene-induced senescence,OIS),从而抑制进一步的肿瘤发生.因而,癌基因的活化具有诱导衰老或肿瘤的双向性.DNA损伤调控反应(DNA damage checkpoint response,DDR)是细胞应对DNA损伤时感应损伤,从而延迟或阻滞细胞周期进程的一种分子信号传递通路,是诱导细胞衰老的重要机制.癌基因的活化可以引发DNA损伤信号的产生,从而激活DDR,诱导细胞衰老.在DDR异常时,癌基因的激活可引发DNA的过度复制与细胞的过度增殖,并导致基因组不稳定性的积累,最终导致肿瘤发生.DDR的完整性决定了癌基因诱导的双向性.DDR在癌基因诱导中的重要作用,提示了保持和恢复DDR的完整性可以作为肿瘤预防和治疗的新方向.

关键词：癌基因细胞衰老癌基因诱导的衰老 DNA损伤调控反应 DNA过度复制

Distribution,formation and evolution of sand ridges on the East china Sea shelf

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science china(Technological sciences) 2010年第3期53卷 822-828页

作者： ZHAO RenBao 1,2,SUN HaiTao 3,WU YaSheng 3 &ZHAO ChuanFeng 1,2 1MOE Key Laboratory of Petroleum Engineering,china university of Petroleum,Beijing 102249,china 2 Enhanced Oil Recovering Research Center,china university of Petroleum,Beijing 102249,china 3faculty of Natural Resource&Information technology,china university of Petroleum,Beijing 102249,china 1. MOE Key Laboratory of Petroleum Engineering China University of Petroleum Beijing 102249 China2. Enhanced Oil Recovering Research Center China University of Petroleum Beijing 102249 China3. Faculty of Natural Resource & Information Technology China University of Petroleum Beijing 102249 China

Influence of CO2 corrosion on reservoir mineralogical composition,pore structure and their mechanical characteristics was studied using XRD,SEM,rock tri-axial machine and core flow experimental *** was found that the corrosion effect was mainly attributed to rock texture and structure,fluid composition and external dynamical conditions in the experimental *** cores with bedding structures,their bedding surfaces were the preferential corrosion regions,because micro-cracks would evolve at these surfaces in the pressure-releasing ***,for cores with massive structures controlled by stable water environment,the CO2 corrosion would result in pore enlargement and secondary pore *** gas velocity from outlet showed sharp increase in the injection process of CO2-H2O *** could be explained by two changes caused by *** was the opening and closure of *** other was particle *** the corrosion time increased,both tensile strength and compressive strength decreased,which confirmed decrease of cementation *** should also be noted that permeability increase and micro-cracks generation would pose damage to the capacity of CO2 geological storage.

关键词： carbon dioxide geological storage mineralization enhanced oil recovery corrosion

Construction of a genetic map and localization of QTLs for yield traits in tomato by SSR markers

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Progress in Natural science:Materials International 2005年第9期15卷 793-797页

作者： LIU Yang 1,2 , CHEN Huoying1**, WEI Yutang2 and ZHUANG Tianming1(1. Department of Plant science, Shanghai Jiaotong university, Shanghai 201101, china 2. Department of Horticulture, Shenyang agricultural university, Shenyang 110161, china) Department of Plant science Shanghai Jiaotong University Shanghai 201101 China. Department of Horticulture Shenyang Agricultural University Shenyang 110161 China

Using an F2population derived from the hybrid of Lycopersicon esculentum Mill. ‘XF 98-7’× Lycopersicon pimpinellifolium LA2184, a SSR genetic linkage map of tomato is constructed. The map contains 112 markers and spans 808.4 cM with an average distance of 7.22 cM between loci. Two quantitative trait loci （QTLs） for first flower node on chromosomes 5 and 11, two QTLs for number of flowers per truss on chromosomes 2 and 5, and five QTLs for fruit weight on chromosomes 1, 2, 3, 9 and 12 are identified.

关键词： tomato SSR markers genetic mapping first flower node number of flowers per truss fruit weight.

Research on the method for retrieving soil moisture using thermal inertia model

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science china Earth sciences 2006年第5期49卷 539-545页

作者： LIU Zhenhua1 & ZHAO Yingshi2 1. Information College, South china agricultural university, Guangzhou 510642, china 2. Graduate university of Chinese Academy of sciences, Beijing 100049, china 1. Information College South China Agricultural University Guangzhou 510642 China 2. Graduate university of Chinese Academy of sciences Beijing 100049 China

In order to improve accuracy of soil moisture inversion using remote sensing, a new thermal inertia model is proposed in this paper. The improved model needs only surface maximum temperature as the temperature parameter input instead of input of the surface temperature difference, as well as the surface sensible and latent fluxes are introduced into boundary conditions of thermal conductivity equation. Furthermore, surface soil conductive heat transfer equation of two-layer model is used to solve the soil thermal inertia so that the remote sensing thermal inertia method can be ap- plied to regions with better-covered vegetation, but usually only for the bare areas or worse vegetation covered areas. The model has been tested at several locations in the area of west Inner Mongolia. Comparing the simulation of the new model with the measurements obtained by apparent thermal inertia and by field test, the result shows that the inertia thermal model can be used to estimate soil moisture in more reasonable accuracy.

关键词： thermal model, thermal conductivity equation, soil initial, sensible flux, latent flux, two-layer model.