|
|
|
题名
|
作者
|
年代
|
出处
|
被引量
|
| 1 | Paleogene-Neogene stratigraphic realm and sedimentary sequence of the Qinghai-Tibet Plateau and their response to uplift of the plateau显示文摘Based on the data of 1:250000 geological mapping completed by CGS and the previous literature of the Cenozoic strata, 98 remnant basins and 5 stratigraphic realms with 13 stratigraphic subrealms have been recognized on the Qinghai-Tibet Plateau and its adjacent area. Through the research of the types of remnant basins, tectonic setting, stratigraphic sequence and sedimentary characteristics, contact relationship between the strata, the formation time and evolution history of sediments, we divided the uplift process and sedimentary response of the Qinghai-Tibet Plateau into 3 stages and 8 sub-stages, namely, subduction-collision uplift stage (65-34 Ma) with three sub-stages, intercontinental convergence and compressive uplift stage (34-13 Ma) with three sub-stages, and intercontinental isostatic adjustment uplift stage (since 13 Ma) with two sub-stages. | ZHANG KeXin WANG GuoCan JI JunLiang LUO ManSheng KOU XiaoHu WANG YueMing XU YaDong CHEN FenNing CHEN RuiMing SONG BoWen ZHANG JianYu LIANG YinPing | 2010 | Science China Earth Sciences2010，53，9： | 49 |
| 2 | Progress and perspectives in dielectric energy storage ceramics显示文摘Dielectric ceramic capacitors,with the advantages of high power density,fast chargedischarge capability,excellent fatigue endurance,and good high temperature stability,have been acknowledged to be promising candidates for solid-state pulse power systems.This review investigates the energy storage performances of linear dielectric,relaxor ferroelectric,and antiferroelectric from the viewpoint of chemical modification,macro/microstructural design,and electrical property optimization.Research progress of ceramic bulks and films for Pb-based and/or Pb-free systems is summarized.Finally,we propose the perspectives on the development of energy storage ceramics for pulse power capacitors in the future. | Dongxu LI Xiaojun ZENG Zhipeng LI Zong-Yang SHEN Hua HAO Wenqin LUO Xingcai WANG Fusheng SONG Zhumei WANG Yueming LI | 2021 | Journal of Advanced Ceramics2021，10，4： | 16 |
| 3 | Aqueous-Phase Synthesis ofAg-TiO2-Reduced Graphene Oxide and Pt-TiO2-Reduced Graphene Oxide Hybrid Nanostructures and Their Catalytic Properties显示文摘我们为 Ag 和 TiO2 粒子在好的混合 nanostructure (NS ) 在 rGO 表上驱散的 Ag-TiO2-reduced graphene 氧化物(rGO ) 的合成表明一个水的答案方法。Ag-TiO2-rGO NS 然后被用作一个模板综合 Pt-TiO2-rGO NS。产生混合 NS 被传播电子显微镜学( TEM )描绘,高分辨率的 TEM ( HRTEM ),精力散的X光检查( EDX )光谱学,X光检查衍射( XRD ),X光检查光电子光谱学( XPS ), Fourier 变换红外线( FTIR )光谱学,紫外力的光谱学,拉曼光谱学,诱导地联合的血浆团 spectrometry ( ICPMS ),和催化研究。TiO2-rGO, Ag-TiO2-rGO 和 Pt-TiO2-rGO NS 都由 NaBH4 为 p-nitrophenol 的减小显示出催化活动到 p-aminophenol,这被发现,并且那 Pt-TiO2-rGO NS 展出最高催化的活动以及优秀稳定性和容易的再循环能力。 | Ping Wang Lei Han Chengzhou Zhu Yueming Zhai Shaojun Dong | 2011 | Nano Research2011，4，11： | 10 |
| 4 | Electrospun Nanofibrous Materials for Wound Healing显示文摘Wound dressing materials which are capable of meeting the demands of accelerating wound closure and promoting wound healing process have being highly desired.Electrospun nanofibrous materials show great application potentials for wound healing owing to relatively large surface area,better mimicry of native extracellular matrix,adjustable waterproofness and breathability,and programmable drug delivery process.In this review article,we begin with a discussion of wound healing process and current commercial wound dressing materials.Then,we emphasize on electrospun nanofibrous materials for wound dressing,covering the efforts for controlling fiber alignment and morphology,constructing 3D scaffolds,developing waterproof-breathable membrane,governing drug delivery performance,and regulating stem cell behavior.Finally,we finish with challenges and future prospects of electrospun nanofibrous materials for wound dressings. | Yuping Dong Yuqi Zheng Keyan Zhang Yueming Yao Lihuan Wang Xiaoran Li Jianyong Yu Bin Ding | 2020 | Advanced Fiber Materials2020，2，4： | 10 |
| 5 | VIBRATION AND SOUND RADIATION OF AN ASYMMETRIC LAMINATED PLATE IN THERMAL ENVIRONMENTS显示文摘Analytical studies on the vibration and sound radiation characteristics of an asymmetric laminated rectangular plate are carried out in this paper. Theoretical formulations, in which the effects of thermal environments are taken into account, are derived for the vibration and sound radiation based on both first-order shear deformation plate theory and Rayleigh integral. It is found that the natural frequencies, the resonant amplitudes of vibration response and the sound pressure level decrease with the temperature rising. The natural frequencies of asymmetric plates are smaller than those of symmetric plates and the velocity responses of asymmetric plates are larger than those of symmetric plates. | Wei Li Yueming Li | 2015 | Acta Mechanica Solida Sinica2015，28，1： | 9 |
| 6 | Glass modified barium strontium titanate ceramics for energy storage capacitor at elevated temperatures显示文摘A glass with composition of B_(2)O_(3)-Bi_(2)O_(3)-SiO_(2)-CaO-BaO-Al_(2)O_(3)-ZrO_(2)(BBSZ)modified Ba_(x)Sr_(1-x)TiO_(3)(BST,x=0.3 and 0.4)ceramics were prepared by a conventional solid state reaction method abided by a formula of BST+y%BBSZ(y=0,2,4,7,and 10,in mass).The effect of BBSZ glass content on the structure,dielectric properties and energy storage characteristics of the ceramics was investigated.The dielectric constant reduced but the endurable electrical strength enhanced due to the BBSZ glass addition in BST ceramics.In particular,the dielectric loss of the ceramics at elevated temperature(e.g.200℃)can be strongly suppressed from tanδ>20%to tanδ<3% after BBSZ glass modification.For Ba_(0.3)Sr_(0.7)TiO_(3)+2%BBSZ ceramics,an optimized energy storage density(γ=0.63 J/cm^(3))and efficiency(η=91.6%)under an applied electric field of 160 kV/cm was obtained at room temperature.Meanwhile,the temperature dependent polarization-electric field(P-E)hysteresis loops were measured to evaluate the energy storage characteristics of the ceramics potential for high voltage capacitor application at elevated temperatures. | Zong-Yang Shen Yu Wang Yanxue Tang Yuanying Yu Wen-Qin Luo Xingcai Wang Yueming Li Zhumei Wang Fusheng Song | 2019 | Journal of Materiomics2019，5，4： | 9 |
| 7 | Optimizing mechanical property and cytocompatibility of the biodegradable Mg-Zn-Y-Nd alloy by hot extrusion and heat treatment显示文摘The Mg-Zn-Y-Nd alloy is a new type of degradable material for biomedical application. In the present study, Mg-6Zn-1.2Y-0.8Nd alloy was fabricated, and then extrusion and heat treatment were conducted to optimize its mechanical properties and cytocompatibility. The microstructure observation, mechanical property, degradation behavior and cytocompatibility tests were conducted on the Mg-Zn-Y-Nd alloy with three different states: as-cast(alloy C), as-extruded(alloy E) and extruded + heat treated(alloy EH).The results show that alloy C consists of coarse grains and continuous secondary phases. The extrusion process has caused incomplete recrystallization, and results in a mixed grain structure of elongated grains and small equiaxed grains(alloy E). The heat treatment process has promoted the recrystallization and homogenized the grain structure(alloy EH). Both the strength and ductility of the alloy has been improved by extrusion, but the following heat treatment has decreased the strength and increased the ductility.The degradation behavior of the alloy C and E alloys does not show much difference, but improves slightly in alloy EH, because the heat treatment has homogenized the microstructure and released the residual stress in the alloy. The directly and indirectly cell viability tests indicate that alloy EH exhibits the best cytocompatibility, which should be ascribed to its relative uniform degradation and low ion releasing rate. In summary, the combination of hot extrusion and heat treatment could optimize the mechanical property and cytocompatibility of the Mg-Zn-Y-Nd alloy together, which is beneficial for the future application of the alloy. | Yiyuan Kang Beining Du Yueming Li Baojie Wang Liyuan Sheng Longquan Shao Yufeng Zheng Tingfei Xi | 2019 | Journal of Materials Science & Technology2019，35，1： | 8 |
| 8 | P-E hysteresis loop going slim in Ba0.3Sr0.7TiO3-modified Bi0.5Na0.5TiO3 ceramics for energy storage applications显示文摘(Ba0.3Sr0.7)x(Bi0.5Na0.5)1-xTiO3(BSxBNT,x=0.3–V0.8)ceramics were prepared to investigate their structure,dielectric and ferroelectric properties.BSxBNT ceramics possess pure perovskite structure accompanied from a tetragonal symmetry to pseudo-cubic one with the increase of x value,being confirmed by X-ray diffraction(XRD)and Raman results.The Tm corresponding to a temperature in the vicinity of maximum dielectric constant gradually decreases from 110℃(x=0.3)to-45℃(x=0.8),across Tm=36℃(x=0.5)with a maximum dielectric constant(ɛr=5920@1 kHz)around room temperature.The saturated polarization Ps gradually while the remnant polarization Pr sharply decreases with the increase of x value,making the P-E hysteresis loop of BSxBNT ceramics goes slim.A maximum difference between Ps and Pr(Ps-Pr)is obtained for BSxBNT ceramics with x=0.5,at which a high recoverable energy density(Wrec=1.04 J/cm3)is achieved under an applied electric field of 100 kV/cm with an efficiency ofη=77%.Meanwhile,the varied temperature P-E loops,fatigue measurements,and electric breakdown characteristics for the sample with x=0.5 indicate that it is promising for pulsed power energy storage capacitor candidate materials. | Dongxu LI Zong-Yang SHEN Zhipeng LI Wenqin LUO Xingcai WANG Zhumei WANG Fusheng SONG Yueming LI | 2020 | Journal of Advanced Ceramics2020，9，2： | 8 |
| 9 | One-Step, Solvothermal Synthesis of Graphene-CdS and Graphene-ZnS Quantum Dot Nanocomposites and Their Interesting Photovoltaic Properties显示文摘The synthesis of graphene-semiconductor nanocomposites has attracted increasing attention due to their interesting optoelectronic properties.However the synthesis of such nanocomposites,with decorated particles well dispersed on graphene,is still a great challenge.This work reports a facile,one-step,solvothermal method for the synthesis of graphene-CdS and graphene-ZnS quantum dot nanocomposites directly from graphene oxide,with CdS and ZnS very well dispersed on the graphene nanosheets.Photoluminescence measurements showed that the integration of CdS and ZnS with graphene significantly decreases their photoluminescence.Transient photovoltage studies revealed that the graphene-CdS nanocomposite exhibits a very unexpected strong positive photovoltaic response,while separate samples of graphene and CdS quantum dots(QDs)of a similar size do not show any photovoltaic response. | Ping Wang Tengfei Jiang Chengzhou Zhu Yueming Zhai Dejun Wang Shaojun Dong | 2010 | Nano Research2010，3，11： | 8 |
| 10 | Clean synthesis of biodiesel over solid acid catalysts of sulfonated mesopolymers显示文摘FDU-15-SO3H,a solid acid material prepared from the sulfonation of FDU-15 mesoporous polymer,has been demonstrated to serve as an efficient catalyst in the esterification of palmitic acid with methanol as well as in the transesterification of fatty acid-edible oil mixture.FDU-15-SO3H achieved an acid conversion of 99.0% when the esterification was carried out at 343 K with a methanol/palmitic acid molar ratio of 6:1 and 5 wt% catalyst loading.It was capable of giving 99.0% yield of fatty acid methyl esters (FAME) when the transesterification of soybean oil was performed at 413 K and the methanol/oil weight ratio of 1:1.FDU-15-SO3H was further applied to the transesterification/esterification of the oil mixtures with a varying ratio of soybean oil to palmitic acid,which simulated the feedstock with a high content of free fatty acids.The yield of FAME reached 95% for the oil mixtures containing 30 wt% palmitic acid.This indicated the sulfonated mesopolymer was a potential catalyst for clean synthesis of fuel alternative of biodiesel from the waste oil without further purification. | FANG Lin,XING Rong,WU HaiHong,LI XiaoHong,LIU YueMing & WU Peng Shanghai Key Laboratory of Green Chemistry and Chemical Processes Department of Chemistry,East China Normal University,Shanghai 200062,China | 2010 | Science China Chemistry2010，53，7： | 7 |
| 11 | Similarity theory for the physical simulation of natural gas hydrate reservoir development显示文摘In order to apply physical simulation results to natural gas hydrate reservoir parameters to provide a theoretical framework for the design of a development plan,an analytical equation method was used to obtain the similarity criteria of natural gas hydrate reservoir development by physical simulation,based on a mathematical model of natural gas hydrate development.Given the approach of numerical simulation,a sensitivity analysis for all parameters was carried out,which specifically demonstrated that initial temperature is the most important parameter.Parameters of thermal conductivity coefficients are not necessary for conducting the NGH dissociation process,which will fundamentally simplify the design and establishment of the model.The analysis provides a sound theoretical basis and design principles for particular similarity. | LIU Yaping CHEN Yueming BAI Yuhu LI Shuxia | 2010 | Mining Science and Technology2010，20，5： | 7 |
| 12 | Oxymatrine reduces neuroinflammation in rat brain A signaling pathway显示文摘Cerebral neuroinflammation models were established by injecting 10 μg lipopolysaccharide into the hippocampus of male Sprague-Dawley rats. The rats were treated with an intraperitoneal injection of 120, 90, or 60 mg/kg oxymatrine daily for three days prior to the lipopolysaccharide injection. Twenty-four hours after model induction, the hippocampus was analyzed by real-time quantitative PCR, and the cerebral cortex was analyzed by enzyme-linked immunosorbent assay and western blot assay. The results of the enzyme-linked immunosorbent assay and the real-time quantitative PCR showed that the secretion and mRNA expression of the pro-inflammatory cytokines interleukin-1β and tumor necrosis factor-α were significantly decreased in the hippocampus and cerebral cortex of model rats treated with oxymatrine. Western blot assay and real-time quantitative PCR analysis indicated that toll-like receptor 4 mRNA and protein expression were significantly decreased in the groups receiving different doses of oxymatrine. Additionally, 120 and 90 mg/kg oxymatrine were shown to reduce protein levels of nuclear factor-κB p65 in the nucleus and of phosphorylated IκBα in the cytoplasm of brain cells, as detected by western blot assay. Experimental findings indicate that oxymatrine may inhibit neuroinflammation in rat brain via downregulating the expression of molecules in the toll-like receptor 4/nuclear factor-κB signaling pathway. | Jiahui Mao Yae Hu Ailing Zhou Bing Zheng Yi Liu Yueming Du Jia Li Jinyang Lu Pengcheng Zhou | 2012 | Neural Regeneration Research2012，7，30： | 7 |
| 13 | A nonlinear POD reduced order model for limit cycle oscillation prediction显示文摘As the amplitude of the unsteady flow oscillation is large or large changes occur in the mean background flow such as limit cycle oscillation,the traditional proper orthogonal decomposition reduced order model based on linearized time or frequency domain small disturbance solvers can not capture the main nonlinear features.A new nonlinear reduced order model based on the dynamically nonlinear flow equation was investigated.The nonlinear second order snapshot equation in the time domain for proper orthogonal decomposition basis construction was obtained from the Taylor series expansion of the flow solver.The NLR 7301 airfoil configuration and Goland+ wing/store aeroelastic model were used to validate the capability and efficiency of the new nonlinear reduced order model.The simulation results indicate that the proposed new reduced order model can capture the limit cycle oscillation of aeroelastic system very well,while the traditional proper orthogonal decomposition reduced order model will lose effectiveness. | CHEN Gang *,LI YueMing & YAN GuiRong MOE Key Laboratory for Strength & Vibration,College of Aerospace,Xi’an Jiaotong University,Xi’an 710049,China | 2010 | Science China(Physics,Mechanics & Astronomy)2010，53，7： | 7 |
| 14 | Active dry yeast supplementation improves the growth performance,rumen fermentation, and immune response of weaned beef calves显示文摘The objective of this experiment was to investigate the potential benefits of active dry yeast(ADY)on the growth performance,rumen fermentation,nutrient digestibility,and serum parameters of weaned beef calves.Thirty Simmental crossbred male calves(body weight=86.47±4.41 kg and 70±4 d of age)were randomly divided into 2 groups:control(CON)(fed basal ration)and ADY(fed basal ration and 5 g/d ADY per calf).The dietary concentrate-to-roughage ratio was 35:65.All the calves were regularly provided rations 3 times a day at 07:00,13:00,and 19:00 and had free access to wate r.The experiment lasted for 60 d.The average daily gain of ADY group was higher(P=0.007)than that of the CON group,and the ratio of feed intake to average daily gain in the ADY group was reduced(P=0.022)as compared to the CON group.The concentration of ruminal ammonia-N was higher(P=0.023)in the CON group than that in the ADY group,but an opposite trend of microbial protein was found between the 2 groups.Also,the ruminal concentrations of propionate and butyrate were higher(P<0.05)in the ADY group than those in the CON group.Calves fed ADY exhibited higher(P<0.05)crude protein and neutral detergent fiber digestibility.Supplementation of ADY increased(P<0.05)the contents of glucose,glutathione peroxidase,superoxide dismutase,immunoglobulin A,immunoglobulin M,and interleukin 10 in the serum of calves,but an opposite trend was observed in malondialdehyde,interleukin 1 beta,and tumor necrosis factor alpha contents between the 2 groups.In conclusion,dietary supplementation with ADY could improve the growth performance,rumen fermentation,nutrient digestibility,antioxidant ability,and immune response of weaned beef calves. | Jian Ma Cheng Wang Zhisheng Wang Guang Cao Rui Hu Xueying Wang Huawei Zou Kun Kang Quanhui Peng Bai Xue Lizhi Wang Yueming Zhu Xiaopeng Zhu | 2021 | Animal Nutrition2021，，4： | 7 |
| 15 | Ce and W co-doped CaBi_(2)Nb_(2)O_(9) with enhanced piezoelectric constant and electrical resistivity at high temperature显示文摘Ce and W co-doped CaBi_(2)Nb_(2)O_(9) ceramics with chemical formula Ca_(0.96)Ce_(0.04)Bi_(2)Nb_(2-x)W_(x)O_(9)(CCBNW100x,x=0-0.07)are fabricated via conventional solid state sintering method,to investigate the effect of W addition on the structure,electrical resistivity,dielectric and piezoelectric properties.A piezoelectric constant d33 of 13.4 pC/N is obtained in CCBN-W2 ceramics,>100% higher than that of pure CaBi_(2)Nb_(2)O_(9)(d_(33)=5.8e6.4 pC/N).Of particular significance is that the electrical resistivity of CCBN-W2 ceramics(r=3.7×109 U cm at 500℃)is three orders of magnitude higher than pure CaBi_(2)Nb_(2)O_(9)(r=2.9×10^(6) U cm at same temperature).All these properties,together with its low dielectric loss(tandδ0.13%)and excellent d33 thermal stability up to 800℃,merit the CCBN-W2 ceramics for high temperature piezoelectric sensing applications. | Zong-Yang Shen Chen Qin Wen-Qin Luo Fusheng Song Zhumei Wang Yueming Li Shujun Zhang | 2020 | Journal of Materiomics2020，6，3： | 7 |
| 16 | A simple way to make pre-stressed ceramics with high strength显示文摘A pre-stressing design and a simple fabrication technology to substantially improve the strength of ceramic components are presented.Residual surface compressive stress is generated in ceramic components by pressureless sintering of a green bulk coated with a thin layer of low coefficient of thermal expansion(CTE).The stress level can be controlled by changing the cross-section area ratio,Young's modulus ratio and CTE ratio of the coating.Pre-stressed ZrO_(2) ceramics coated with Al_(2)O_(3) can achieve a flexural strength of 1330±52MPa,45% higher than their uncoated counterpart.Similarly,the flexural strength of building porcelain tiles is increased by 70%,from 67±3 MPa to 114±5MPa.The damage tolerance of pre-stressed ZrO_(2) ceramics is excellent with a high residual strength of ~1200 MPa in a thermal shock test at 325℃.This simple technique can improve the mechanical performance of ceramic components with no limitation of size and shape. | Yiwang Bao Fenghua Kuang Yi Sun Yueming Li Detian Wan Zongyang Shen Delong Ma Lingfeng He | 2019 | Journal of Materiomics2019，5，4： | 7 |
| 17 | Transcriptome analysis reveals key differentially expressed genes involved in wheat grain development显示文摘Wheat seed development is an important physiological process of seed maturation and directly affects wheat yield and quality. In this study, we performed dynamic transcriptome microarray analysis of an elite Chinese bread wheat cultivar(Jimai 20) during grain development using the Gene Chip Wheat Genome Array. Grain morphology and scanning electron microscope observations showed that the period of 11–15 days post-anthesis(DPA) was a key stage for the synthesis and accumulation of seed starch. Genome-wide transcriptional profiling and significance analysis of microarrays revealed that the period from 11 to 15 DPA was more important than the 15–20 DPA stage for the synthesis and accumulation of nutritive reserves.Series test of cluster analysis of differential genes revealed five statistically significant gene expression profiles. Gene ontology annotation and enrichment analysis gave further information about differentially expressed genes, and Map Man analysis revealed expression changes within functional groups during seed development. Metabolic pathway network analysis showed that major and minor metabolic pathways regulate one another to ensure regular seed development and nutritive reserve accumulation. We performed gene co-expression network analysis to identify genes that play vital roles in seed development and identified several key genes involved in important metabolic pathways. The transcriptional expression of eight key genes involved in starch and protein synthesis and stress defense was further validated by q RT-PCR. Our results provide new insight into the molecular mechanisms of wheat seed development and the determinants of yield and quality. | Yonglong Yu Dong Zhu Chaoying Ma Hui Cao Yaping Wang Yanhao Xu Wenying Zhang Yueming Yan | 2016 | The Crop Journal2016，4，2： | 6 |
| 18 | Novel circular RNA expression profile of uveal melanoma revealed by microarray显示文摘Objective: The present study aimed to investigate circular RNA(circRNA) expression in uveal melanoma(UM).Methods: First,we used microarray to compare the expression profiles of circRNA in five UM samples and five normal uvea tissues.Next,bioinformatics analyses,including gene ontology(GO) analysis and pathway analysis,were applied to study these differentially expressed circRNAs to predict pathogenic pathways that may be involved.Quantitative real-time polymerase chain reaction(qRT-PCR) in 20 UM samples and 20 normal uvea samples was used to confirm the circRNA expression profiles obtained from the microarray data.Finally,we analyzed the interaction between validated circRNAs and their potential cancer-associated miRNA targets.Results: In total,50,579 circRNAs [fold change(FC) ≥2.0; P<0.05],including 20,654 up-regulated and 29,925 down-regulated circRNAs,were identified as differentially expressed between UM tissues and normal uvea tissues.We used qRT-PCR to verify seven dysregulated circRNAs indicated by the microarray data,including hsa_circ_0119873,hsa_circ_0128533,hsa_circ_0047924,hsa_circ_0103232,hsa-circRNA10628-6,hsa_circ_0032148 and hsa_circ_0133460,which may be promising candidates to study future molecular mechanisms.Conclusions: This study explored,for the first time,the abnormal expression of circRNAs in UM and described the expression profile of circRNAs,providing a new potential target for the mechanism of UM and future treatment of UM. | Xuan Yang Yang Li Yueming Liu Xiaolin Xu Yingzhi Wang Yanni Yan Wenjia Zhou Jingyan Yang Wenbin Wei | 2018 | Chinese Journal of Cancer Research2018，30，6： | 6 |
| 19 | Dolomitization by Penesaline Sea Water in Early Cambrian Longwangmiao Formation, Central Sichuan Basin, China显示文摘The Lower Cambrian Longwangmiao Formation shoal dolostone reservoir in Sichuan Basin is currently an exploration and research highlight in China. Reservoir rocks mainly consist of crystalline dolomite with residual grain texture, and dolarenite of which the arene is mainly composed of muddy to micritic dolomite with some crystalline grain directionally aligned. The trace element indicates that the dolomites of Longwangmiao Formation may be related to the high salinity of sea water. The oxygen isotope values of crystalline dolomite and dolarenite are both similar to that of the Early Cambrian marine dolomites, and the carbon isotope values of every kind of dolomites are completely overlapped with that of the seawater in Early Cambrian, indicating the dolomitization fluid is originated from the Early Cambrian sea water. The restricted marine biological communities and a small amount of gypsum pseudonodule seen in muddy to micritic dolomite indicate that the sea water in Early Cambrian was restricted and evaporated. However, the general lack of massive evaporite mineral and gypsum karst breccia indicates that the salinity of sea water during dolomitization was lower than the value of gypsum's precipitation. The Longwangmiao Formation consists of several high-frequency sedimentary cycles, indicating frequent sea level changes. This study indicates that massive dolomitization may also occur in underwater palaeohigh in carbonate platform through the reflux of penesaline sea water driven by a combination of high-and low-frequency sea-level changes. This kind of dolomitization can explain the generation of massive dolomites in the absence of evaporite precipitation, and further indicates that replacement dolomites can be produced by sea water with a wide range of salinity(normal, penesaline to hypersaline). | Xuefei Yang Hao Tang Xingzhi Wang Yaping Wang Yueming Yang | 2017 | Journal of Earth Science2017，28，2： | 6 |
| 20 | Crystal structures of D-psicose 3-epimerase from Clostridium cellulolyticum H10 and its complex with ketohexose sugars显示文摘D-Psicose 3-epimerase(DPEase)is demonstrated to be useful in the bioproduction of D-psicose,a rare hexose sugar,from D-fructose,found plenty in nature.Clostridium cellulolyticum H10 has recently been identified as a DPEase that can epimerize D-fructose to yield D-psicose with a much higher conversion rate when compared with the conventionally used DTEase.In this study,the crystal structure of the C.cellulolyticum DPEase was determined.The enzyme assembles into a tetramer and each subunit shows a(β/α)8 TIM barrel fold with a Mn2+metal ion in the active site.Additional crystal structures of the enzyme in complex with substrates/products(D-psicose,D-fructose,D-tagatose and D-sorbose)were also determined.From the complex structures of C.cellulolyticum DPEase with D-psicose and D-fructose,the enzyme has much more interactions with D-psicose than D-fructose by forming more hydrogen bonds between the substrate and the active site residues.Accordingly,based on these ketohexosebound complex structures,a C3-O3 proton-exchange mechanism for the conversion between D-psicose and D-fructose is proposed here.These results provide a clear idea for the deprotonation/protonation roles of E150 and E244 in catalysis. | Hsiu-Chien Chan Yueming Zhu Yumei Hu Tzu-Ping Ko Chun-Hsiang Huang Feifei Ren Chun-Chi Chen Yanhe Ma Rey-Ting Guo Yuanxia Sun | 2012 | Protein & Cell2012，3，2： | 6 |
您所在的机构暂未开通此部分的功能，请联系管理员