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Girvanella fossils from the Phanerozoic:Distribution, evolution and controlling factors

Journal of Palaeogeography 2024年第4期13卷 924-938页

作者： hua-shan zhang Ming-Yue Dai Yong-An Qi Lan-Lan Han Zhong-Lei Yin Song-hua Chen Liang-Biao Lin Institute of Sedimentary Geology Chengdu University of Technology School of Resources and Environment Henan Polytechnic University

Girvanella is one of the common genera of cyanobacteria that plays a monumental role in the evolution of life on Earth and the formation of *** on a detailed search in the literature of Girvanella fossils,we have compiled a global database of Girvanella fossils and revealed the evolution of Girvanella fossils throughout the *** species,Girvanella kasakiensis,Girvanella problematica,Girvanella wetheredii,and Girvanella staminea,are recognized and *** data show that Girvanella fossils have well-defined temporal distribution during the Paleozoic Era,have a significant temporal gap in the Mesozoic Era,and have only been recorded sporadically in the Cenozoic *** were relatively abundant during the Cambrian Epoch 2-Early Ordovician,Late Ordovician,Late Devonian-Mississippian,and tended to lesser degrees during the Silurian-Early Devonian,Lopingian Epoch-Middle Jurassic,and Cretaceous-Present ***,the evolution of the abundance and diversity of Girvanella fossils was fundamentally consistent and showed episodical declining during the *** further explore these relationships,we thoroughly compared them with environmental factors such as seawater carbonate saturation state,Ca2+concentration,pH values,and atmospheric partial pressure of carbon dioxide （p CO2）.This study indicates that seawater carbonate saturation state and Ca2+concentration are major controls on secular patterns of the abundance and diversity of Girvanella fossils,together with the secondary factors of pH values and p *** the long history of Girvanella fossils,their abundance and diversity offer the potential to assist the interpretation of the long-term evolution of marine and atmosphere components during the Phanerozoic.

关键词： Girvanella Temporal distribution Abundance Diversity Control factors

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Giant ooids of microbial origin from the zhangxia Formation(Cambrian Miaolingian Series)in North China

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Journal of Palaeogeography 2022年第1期11卷 52-68页

作者： Ming-Yue Dai hua-shan zhang Wei Zheng Yong-An Qi Zhi-Feng Xing Zhen zhang School of Resources and Environment Henan Polytechnic UniversityJiaozuo 454003China Key Laboratory of Biogenic Traces and Sedimentary Minerals of Henan Province Henan Polytechnic UniversityJiaozuo 454003China

The role of microorganisms in the formation of giant ooids is one of the areas of long-term controversy in ooidal research,but it has not been confirmed *** giant ooids developed in the zhangxia Formation of the Cambrian Miaolingian Series in North *** ooids in the study area were examined by using Polarized Light Microscopy and Field Emission Environmental Scanning Electron *** nuclei of the ooids consist of micritic pellets or radial ooids with diameters less than 2 mm and are formed in a weak-agitating seawater *** cortices are concentric,and are characterized by the alternations of the dark laminae of micritic calcite or Girvanella filaments and light laminae of microsparry *** the environments of inter-bank sea with the alternating development of medium and low energy and chiefly weak-agitating conditions,giant ooids were formed under the joint action of Girvanella filamentous growth,biologically-induced calcification and/or biologically-influenced calcification and inorganic calcium carbonate *** microfossils of Girvanella are distributed in inner and outer cortices of giant ooids,especially dense in the *** distinctly indicates that microbes play a significant role in the formation of giant ooids,and also provides a vital example for discussing the microbial origin of giant ooids.

关键词： Girvanella filament Microbial origin Giant ooid Cambrian Miaolingian Series zhangxia Formation North China

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Incubation and development of corrosion in microstructures of low alloy steels under a thin liquid film of NaCl aqueous solution

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International Journal of Minerals,Metallurgy and Materials 2010年第6期17卷 748-755页

作者： Wen-hua zhang shan-wu Yang Jia Guo Zhi-yong Liu Xin-lai He School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

Electrochemical measurement, optical microscopy, and scanning electron microscopy were employed to investigate the corrosion behavior of some low alloy steels. The steels were held under a thin liquid film of 0.5wt% NaCl aqueous solution. It is found that the steels with the same chemical composition but different micmstructures exhibit obviously different corrosion behaviors. However, the corrosion behavior of the steels with different compositions but the same microstructnres may be similar in the present investigation. The corrosion rate of bainite is slower than that of ferrite and pearlite. The corrosion products of bainite are uniform and fine. The size of carbon-rich phases produces a great impact on the corrosion of the steels, whether in the initial stage or in the long tenn. It is easy to induce large pitting for carbon-rich phases with large size, which damages the compactness of the rust layer.

关键词： alloy steel microstructure atmospheric corrosion liquid films scanning electron microscope

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Study on Triplex DNA by Use of Molecular“hight Switch”Complex of Ru(phen)_(2)(dppx)^(2+)

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Chinese Chemical Letters 2003年第3期14卷 300-303页

作者： Lian Sheng LING Zhi Ke HE Fang CHEN hua shan zhang Yun E ZENG Department of Chemistry Wuhan UniversityWuhan 430072 Institute of Chemistry the Chinese Academy of SciencesBeijing 100080

A new method for the study of triplex DNA is established according the fluorescence enhancement of molecular 揕ight Switch?complex of Ru(phen)2(dppx)2+ when it intercalate into triplex DNA. Because the fluorescence intensity of Ru(phen)2(dppx)2+ bonded to triplex DNA is in the case higher than that bonded to duplex DNA in certain range of DNA concentration, the method is much more sensitive than other methods reported previously.

关键词： Molecular "Light Switch" Ru(phen)2(dppx)2+ Triplex DNA

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Evolution and Application of Sealing Ability of Gypsum Caprocks under Temperature-Pressure Coupling:An Example of the ZS5 Well in the Tazhong Area of the Tarim Basin

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Acta Geologica Sinica(English Edition) 2024年第1期98卷 168-184页

作者： LIU hua ZHAO shan YANG Xianzhang ZHU Yongfeng WANG Shen zhang Ke National Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)QingdaoShandong 266580China School of Geosciences China University of Petroleum(East China)QingdaoShandong 266580China Laboratory for Marine Mineral Resources National Laboratory for Marine Science and TechnologyQingdaoShandong 266071China PetroChina Tarim Oil Field Company KorlaXinjiang 841001China

Gypsum caprocks'sealing ability is affected by temperature-pressure *** to the limitations of experimental conditions,there is still a lack of triaxial stress-strain experiments that simultaneously consider changes in temperature and pressure conditions,which limits the accuracy of the comprehensive evaluation of the brittle plastic evolution and sealing ability of gypsum rocks using temperature pressure *** stress-strain tests were utilized to investigate the differences in the evolution of the confinement capacity of gypsum rocks under coupled temperaturepressure action and isothermal-variable pressure action on the basis of sample feasibility *** to research,the gypsum rock's peak and residual strengths decrease under simultaneous increases in temperature and pressure over isothermal pressurization experimental conditions,and it becomes more *** reduces the amount of time it takes for the rock to transition from brittle to *** temperature is taken into account,both the brittle–plastic transformation's depth limit and the lithological transformation of gypsum rocks become shallower,and the evolution of gypsum rocks under variable temperature and pressure conditions is more complicated than that under isothermal *** sealing ability under the temperature-pressure coupling is more in line with the actual geological context when the application results of the Well#ZS5 are *** provides a theoretical basis for precisely determining the process of hydrocarbon accumulation and explains why the early hydrocarbon were not well preserved.

关键词： temperature-pressure coupling gypsum caprocks brittle-plastic evolution sealing capacity Tarim Basin

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Oxidative Damage to Lung Tissue and Peripheral Blood in Endotracheal PM_(2.5)-treated Rats

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Biomedical and Environmental Sciences 2009年第3期22卷 223-228页

作者： ZHI-QING LIN ZHU-GE XI DAN-FENG YANG Fu-huaN CHAO hua-shan zhang WEI zhang huaNG-LIANG LIU ZAI-MING YANG RU-BAO SUN Institute of Health and Environmental Medicine Tianjin 300050 China State Environmental Protection Key Laboratory of Urban Ambient Air Particulate Matter Pollution Prevention and Control Tianjin 300071 China

Objective To investigate the oxidative damage to lung tissue and peripherial blood in PM2.5-treated rats. Methods PM2.5 samples were collected using an auto-sampling instrument in summer and winter. Treated samples were endotracheally instilled into rats. Activity of reduced glutathione peroxidase （GSH-Px） and concentration of malondialdehyde （MDA） were used as oxidative damage biomarkers of lung tissue and peripheral blood detected with the biochemical method. DNA migration length （μm） and rate of tail were used as DNA damage biomarkers of lung tissue and peripheral blood detected with the biochemical method. Results The activity of GSH-Px and the concentration of MDA in lung tissue significantly decreased after exposure to PM2.5 for 7-14 days. In peripheral blood, the concentration of MDA decreased, but the activity of GSH-Px increased 7 and 14 days after experiments. The two indicators had a dose-effect relation and similar changing tendency in lung tissue and peripheral blood. The DNA migration length （μm） and rate of tail in lung tissue and peripheral blood significantly increased 7 and 14 days after exposure to PM2.5. The two indicators had a dose-effect relation and similar changing tendency in lung tissue and peripheral blood. Conclusion PM2.5 has a definite oxidative effect on lung tissue and peripheral blood. The activity of GSH-Px and the concentration of MDA are valuable biomarkers of oxidative lung tissue damage induced by PM2.5. The DNA migration length （μm） and rate of tail are simple and valuable biomarkers of PM2 5-induced DNA damage in lung tissues and peripheral blood. The degree of DNA damage in peripheral blood can predict the degree of DNA damage in lung tissue.

关键词： PM2.5 Endotracheal instillation Oxidative damage Oxidative DNA damage Biomarker DNA repair

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The RNA-binding domain of DCL3 is required for long-distance RNAi signaling

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aBIOTECH 2024年第1期5卷 17-28页

作者： Jie Li Bo-Sen zhang hua-Wei Wu Cheng-Lan Liu Hui-shan Guo Jian-hua Zhao State Key Laboratory of Plant Genomics Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China CAS Center for Excellence in Biotic Interactions University of the Chinese Academy of SciencesBeijing 100049China Qilu Zhongke Academy of Modern Microbiology Technology Jinan 250022China

Small RNA(sRNA)-mediated RNA silencing(also known as RNA interference,or RNAi)is a conserved mechanism in eukaryotes that includes RNA degradation,DNA methylation,heterochromatin formation and protein translation *** plants,sRNAs can move either cell-to-cell or systemically,thereby acting as mobile silencing signals to trigger noncell autonomous ***,whether and what proteins are also involved in noncell autonomous silencing have not been *** this study,we utilized a previously reported inducible RNAi plant,PDSi,which can induce systemic silencing of the endogenous PDS gene,and we demonstrated that DCL3 is involved in systemic PDS silencing through its RNA binding *** confirmed that the C-terminus of DCL3,including the predicted RNA-binding domain,is capable of binding short *** affecting RNA binding,but not processing activity,reduced systemic PDS silencing,indicating that DCL3 binding to RNAs is required for the induction of systemic *** mosaic virus infection assays showed that the RNA-binding activity of DCL3 is required for antiviral RNAi in systemically noninoculated *** findings demonstrate that DCL3 acts as a signaling agent involved in noncell autonomous silencing and an antiviral effect in addition to its previously known function in the generation of 24-nucleotide sRNAs.

关键词： RNAi signaling DCL3 RBD RNAs Cucumber mosaic virus

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Ultra-high-rate Bi anode encapsulated in 3D lignin-derived carbon framework for sodium-ion hybrid capacitors

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Rare Metals 2024年第3期43卷 1037-1047页

作者： Ze-hua Lin Xue-Qing Qiu Xi-Hong Zu Xiao-shan zhang Lei Zhong Shi-Rong Sun Shu-hua Hao Ying-Juan Sun Wen-Li zhang School of Chemical Engineering and Light Industry Guangdong University of Technology(GDUT)Guangzhou510006China Jieyang Branch of Chemistry and Chemical Engineering Guangdong Laboratory(Rongjiang Laboratory) Jieyang515200China School of Advanced Manufacturing Institute of Green Chemistry and Advanced MaterialsGuangdong University of TechnologyJieyang515200China

Bismuth(Bi),as an alloy-based anode material,has attracted much atte ntion in the developme nt of sodiumion hybrid capacitors(SIHCs)due to its high theoretical ***,the volume expansion of the Bi-based anode during the sodiation/desodiation process results in limited rate *** the present work,a porous Bi-based composite was constructed by a one-step hydrothermal method,and Bi was encapsulated in ligninderived nitrogen-doped porous carbon(Bi@LNPC)after *** obtained Bi nanoparticles could effectively adapt to the strain and shorten the diffusion distance of Na^(+).In addition,porous carbon skeleton provides a rigid conductive network for electronic ***,the assembled sodium-ion half-cell with Bi@LNPC anode shows ultra-high-rate *** the current density was enhanced from 0.1 to 50 A·g^(-1),the specific capacity decreased slightly from 351.5 to 342.8 mAh·g^(-1).Even at an extremely high current density of 200 A·g^(-1),it retains 81.3%capacity retention when compared to a current density of 1 A·g^(-1).The SIHCs assembled by Bi@LNPC show a high energy density of 63 Wh·kg^(-1).This work provides an effective method for developing high-rate Bi anode materials for sodium-ion hybrid capacitors(SIHCs)and sodium-ion batteries(SIBs).

关键词： Bismuth Lignin Sodium-ion batteries Sodium-ion hybrid capacitors Rate Porous carbon

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On the Pathwise Uniqueness of Solutions of One-dimensional Reflected Stochastic Differential Equations with Jumps

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Acta Mathematicae Applicatae Sinica 2024年第1期40卷 149-163页

作者： hua zhang School of Statistics and Data Science&Key Laboratory of Data Science in Finance and Economics Jiangxi University of Finance and EconomicsNanchang330013China

In this paper, we are concerned with the problem of the pathwise uniqueness of one-dimensional reflected stochastic differential equations with jumps under the assumption of non-Lipschitz continuous coefficients whose... 详细信息

关键词： reflected diffusion processes with jumps pathwise uniqueness local time Meyer It?'s formula

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Nuclear charge radius predictions by kernel ridge regression with odd-even effects

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Nuclear Science and Techniques 2024年第2期35卷 94-102页

作者： Lu Tang Zhen-hua zhang Mathematics and Physics Department North China Electric Power UniversityBeijing 102206China Hebei Key Laboratory of Physics and Energy Technology North China Electric Power UniversityBaoding 071000China

The extended kernel ridge regression(EKRR)method with odd-even effects was adopted to improve the description of the nuclear charge radius using five commonly used nuclear *** are:(i)the isospin-dependent A^(1∕3) formula,(ii)relativistic continuum Hartree-Bogoliubov(RCHB)theory,(iii)Hartree-Fock-Bogoliubov(HFB)model HFB25,(iv)the Weizsacker-Skyrme(WS)model WS*,and(v)HFB25**** the last two models,the charge radii were calculated using a five-parameter formula with the nuclear shell corrections and deformations obtained from the WS and HFB25 models,*** each model,the resultant root-mean-square deviation for the 1014 nuclei with proton number Z≥8 can be significantly reduced to 0.009-0.013 fm after considering the modification with the EKRR *** best among them was the RCHB model,with a root-mean-square deviation of 0.0092 *** extrapolation abilities of the KRR and EKRR methods for the neutron-rich region were examined,and it was found that after considering the odd-even effects,the extrapolation power was improved compared with that of the original KRR *** strong odd-even staggering of nuclear charge radii of Ca and Cu isotopes and the abrupt kinks across the neutron N=126 and 82 shell closures were also calculated and could be reproduced quite well by calculations using the EKRR method.

关键词： Nuclear charge radius Machine learning Kernel ridge regression method

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