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Coupling of the recovery of earliest Silurian sponges and ocean redox conditions:Evidence from South China

Journal of Palaeogeography 2023年第2期12卷 311-330页

作者： Yong Wang Joseph P.Botting jing-qiang tan Ming Li Wen-Hui Wang School of Geosciences and Info-Physics Central South UniversityChangsha 410083Hunan ProvinceChina Department of Natural Sciences Amgueddfa Cymru-National Museum WalesCathays ParkCardiff CF103LPUK Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China

Many aspects of the Late Ordovician Mass Extinction(LOME)aftermath and recovery have been puzzling due to heterogeneities in tempo and triggering *** fossil groups,which are the most severely affected by oxidative stress,offer the best opportunities for understanding both biological and ecological recovery after the *** recent studies,deep-water sponge assemblages(which may have had high physiological tolerance to oxygen deviations)have been reported widely across South China in the immediate aftermath of the extinction *** order to further explore the lateral and temporal distributions of sponges,and ecological effects of benthic recovery during this critical interval,this study presents new Llandovery sponge assemblages recovered from two sections in Hunan Province,South China,accompanied by geochemical *** sponge communities are preserved by pyritic spicule replacements and shows a relatively deep-water affinity(estimated around 60-150 m in depth)comparable to several previously reported assemblages in South China,and consistent with the observed graptolite *** analysis of total organic carbon(TOC)and major and trace element composition in both sections show similar trends,indicating a shift in redox state of the bottom-water from persistent anoxia or intermittent euxinia in the earliest Rhuddanian,becoming oxygenated in the early *** on the present study and previous biological and geochemical data from South China,the distribution of early Silurian sponge assemblages in South China demonstrates a gradual expansion towards deeper regions when ocean redox conditions *** study confirms the continuity of the end-Ordovician sponge faunas and taxa,both laterally across South China,and temporally through the early *** pioneering colonization of sponges in low-oxygen environments after the LOME may have set the stage for the subsequent recovery of other benthic organisms.

关键词： Llandovery South China Graptolite Proliferation Geochemistry Ecological recovery

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Effects of the extrusion parameters on microstructure,texture and room temperature mechanical properties of extruded Mg-2.49Nd-1.82Gd-0.2Zn-0.2Zr alloy

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 136-146页

作者： Chenjin Zhang Guangyu Yang Lei Xiao Zhiyong Kan jing Guo qiang Li Wanqi Jie State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China College of Materials Science and Engineering Fuzhou UniversityFuzhou 350108China College of Chemistry and Environmental Science Qujing Normal UniversityQujing 655011China

Microstructure,texture,and mechanical properties of the extruded Mg-2.49Nd-1.82Gd-0.2Zn-0.2Zr alloy were investigated at different extrusion temperatures(260 and 320℃),extrusion ratios(10:1,15:1,and 30:1),and extrusion speeds(3 and 6 mm/s).The experimental results exhibited that the grain sizes after extrusion were much finer than that of the homogenized alloy,and the second phase showed streamline distribution along the extrusion direction(ED).With extrusion temperature increased from 260 to 320℃,the microstructure,texture,and mechanical properties of alloys changed *** dynamic recrystallization(DRX)degree and grain sizes enhanced as the extrusion ratio increased from 10:1 to 30:1,and the strength gradually decreased but elongation(EL)*** the extrusion speed increased from 3 to 6 mm/s,the grain sizes and DRX degree increased significantly,and the samples presented the typical-rare-earth(RE)*** alloy extruded at 260℃ with extrusion ratio of 10:1 and extrusion speed of 3 mm/s showed the tensile yield strength(TYS)of 213 MPa and EL of 30.6%.After quantitatively analyzing the contribution of strengthening mechanisms,it was found that the grain boundary strengthening and dislocation strengthening played major roles among strengthening *** results provide some guidelines for enlarging the industrial application of extruded Mg-RE alloy.

关键词： Mg-rare earth alloys extrusion temperature extrusion ratio extrusion speed strengthening mechanisms

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Molecular mechanisms of tumor resistance to PI3K-mTOR-targeted therapy

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Chinese Journal of Cancer 2013年第7期32卷 376-379页

作者： jing tan qiang Yu Cancer Therapeutics and Stratified Oncology Genome Institute of SingaporeA*STAR(Agency for ScienceTechnology and Research)BiopolisSingapore 138672Singapore Department of Physiology Yong Loo Lin School of MedicineNational University of SingaporeSingapore 117599Singapore Cancer and Stem Cell Biology DUKE-NUS Graduate Medical School of SingaporeSingapore 169857Singapore

Deregulation of the phosphatidylinositide 3-kinase(PI3K) and mammalian target of rapamycin(mTOR) signaling pathway occurs frequently in a wide range of human cancers and is a major driving force in ***,small molecules targeting this pathway are under active development as anticancer *** small-molecule inhibitors of the PI3K-mTOR pathway have shown promising clinical efficacy against human cancers,the emergence of drug resistance may limit their success in the *** date,several resistance mechanisms,including both PI3K-dependent and-independent mechanisms,have been ***,we summarize the current understanding of resistance mechanisms to PI3K-mTOR inhibitors and discuss potential strategies for overcoming resistance for potential clinical application.

关键词：分子机制肿瘤耐药靶向治疗信号通路磷脂酰肌醇放松管制 mTOR 雷帕霉素

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五彩湾凹陷石炭系油气成藏控制因素及勘探建议

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新疆石油学院学报 2002年第4期14卷 4-7页

作者：贺凯王菁谭强新疆油田公司准东采油厂勘探开发研究所新疆阜康831511

石炭统滴水泉组高成熟的烃源岩为五彩湾凹陷石炭系提供了较为丰富的气源,彩25井区石炭系顶面为一大型鼻状构造,在此背景下局部高点控制了油气的分布。石炭系存在三个地质界面,其中第一个界面即石炭系风化壳是油气聚集的有利场所,其溶孔... 详细信息

石炭统滴水泉组高成熟的烃源岩为五彩湾凹陷石炭系提供了较为丰富的气源,彩25井区石炭系顶面为一大型鼻状构造,在此背景下局部高点控制了油气的分布。石炭系存在三个地质界面,其中第一个界面即石炭系风化壳是油气聚集的有利场所,其溶孔、溶洞的发育程度直接影响了各井的产能。因此,在该区石炭系油气藏受构造和岩性物性的双重控制,是该区石炭系形成孤立油气藏的主要原因。今后的勘探应以该界面为主要目的层,以寻找高效的串珠状的油气藏为主。

关键词：五彩湾凹陷石炭系油气成藏控制因素油气勘探

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Solidification Microstructure of Laser Additive Manufactured Ti—6Al—2Zr—2Sn—3Mo—1.5Cr—2Nb Titanium Alloy

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Journal of Materials Science & Technology 2016年第4期32卷 381-386页

作者： qiang Zhang jing Chen Lilin Wang Hua tan Xin Lin Weidong Huang State Key Laboratory of Solidification Processing Northwestern Polytechnical University

Solidification microstructure of powder fed laser additive manufactured Ti-6Al--2Zr--2Sn--3Mo--1.5Cr--2Nb titanium alloy was investigated, The results showed that by deliberately increasing the powder feed rate, partially melted powders were retained at the top of the molten pool, which can promote heteroge- neous nucleus. Thus, each cladding layer is composed of two regions：（i） randomly orientated cellular structure region caused by partially melted powders at the top of each cladding layer; and （ii） epitaxial cellular structure region adjacent to the fusion line. Usually, randomly orientated cellular structure region was totally remelted for a wide range of process conditions. The remelting effect ensures the continuity of epitaxial growth of cellular structure and leads to the formation of columnar β grains, In order to obtain equiaxed grains the scanning velocity and powder feed rate should be carefully selected to enlarge the randomly orientated cellular structure region,

关键词： Laser additive manufacturePartially melted powdersEqoiaxed grains

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Multi-shelled CuO microboxes for carbon dioxide reduction to ethylene

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Nano Research 2020年第3期13卷 768-774页

作者： Dongxing tan Jianling Zhang Lei Yao Xiuniang tan Xiuyan Cheng qiang Wan Buxing Han Lirong Zheng jing Zhang Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of ColloidInterface and Chemical ThermodynamicsCAS Research/Education Center for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing100190China School of Chemical Sciences University of Chinese Academy of SciencesBeijing100049China Physical Science Laboratory Huairou National Comprehensive Science CenterBeijing101400China Beijng Synchrotron Radiation Facility(BSRF) Institute of High Energy PhysicsChinese Academy of SciencesBeijing100049China

The electroreduction of CO2 to valuable chemicals and fuels offers an effective mean for energy *** CO2 has been efficiently converted into C1 products(e.g.,carbon monoxide,formic acid,methane and methanol),its convention into high value-added multicarbon hydrocarbons with high selectivity and activity still remains *** we demonstrate the formation of multi-shelled CuO microboxes for the efficient and selective electrocatalytic CO2 reduction to *** a structure favors the accessibility of catalytically active sites,improves adsorption of reaction intermediate(CO),inhibits the diffusion of produced OH−and promotes C-C coupling *** to these unique advantages,the multi-shelled CuO microboxes can effectively convert CO2 into C2H4 with a maximum faradaic efficiency of 51.3%in 0.1 M *** work provides an effective way to improve CO2 reduction efficiency via constructing micro-and nanostructures of electrocatalysts.

关键词： multi-shelled CuO microboxes nanocrystals CO2 reduction C2H4

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铜基催化剂在乙炔氢氯化反应中的工业应用评估

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现代化工 2025年第1期45卷 72-76页

作者：代元元杨京林牛强内蒙古鄂尔多斯电力冶金集团股份有限公司内蒙古鄂尔多斯016064

概述了近年来国内外铜催化剂在乙炔氢氯化反应中的研究进展,综述了铜催化剂的几种改性手段,探讨了催化剂的工业应用情况,分析了铜催化剂工业应用的安全风险问题。研究表明,经过适当改性,铜催化剂具备工业应用潜力,且在实际工业生产中通... 详细信息

概述了近年来国内外铜催化剂在乙炔氢氯化反应中的研究进展,综述了铜催化剂的几种改性手段,探讨了催化剂的工业应用情况,分析了铜催化剂工业应用的安全风险问题。研究表明,经过适当改性,铜催化剂具备工业应用潜力,且在实际工业生产中通过严格控制工艺指标可避免铜工业应用的安全风险问题。

关键词：乙炔氢氯化铜催化剂工业化应用安全性

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Leclercia adecarboxylata infective endocarditis in a man with mitral stenosis:A case report and review of the literature

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World Journal of Clinical Cases 2022年第29期10卷 10670-10680页

作者： Rui tan Jiang-Quan Yu jing Wang Rui-qiang Zheng Department of Critical Care Medicine Northern Jiangsu People’s HospitalYangzhou 225001Jiangsu ProvinceChina

BACKGROUND Infective endocarditis(IE) is a rare disease with a high mortality *** adecarboxylata(***) is a movable Gram-negative bacillus of enterobacteriaceae,and it can rarely be a pathogen which often affects immunodeficient *** are about three cases of immunocompetent patients with monomicrobial *** *** are only three reported cases of IE caused by *** in the *** mitral valve is often affected in IE,and the prognosis for IE with mitral valve lesions is often *** SUMMARY A 51-year-old man was found to have moderate to severe mitral stenosis on *** came to our Cardiothoracic Surgery Department for surgical management.A diastolic murmur was heard on auscultation of the heart in the mitral *** the second day of hospitalisation,he presented with slurred speech,reduced muscle strength in the left limb,and acute cerebral infarction on cranial computed *** treatment was decided to *** the ninth day of admission,the patient developed a sudden high fever and shock and was transferred to the Cardiac Intensive Care Unit,where echocardiogram revealed an anterior mitral valve leaflet *** empirical anti-infective treatment with vancomycin(1g q12h),an emergency valve replacement was *** culture identified *** treatment with piperacillin-tazobactam(4.5g q8h) was added for 4 ***-up echocardiography showed normal bioprosthetic valve function after mitral valve *** We report the first case of *** IE in China,and clinicians should pay attention to this pathogen.

关键词： Leclercia adecarboxylata Infective endocarditis Mitral valve Vegetation Cerebral infarction Case report

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Evaluation of mountain slope stability considering the impact of geological interfaces using discrete fractures model

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Journal of Mountain Science 2019年第9期16卷 2184-2202页

作者： WANG Lu-yu CHEN Wei-zhong tan Xu-yan tan Xian-jun YUAN jing-qiang LIU Qi State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil Mechanics Chinese Academy of Sciences Wuhan 430071 China University of Chinese Academy of Science Beijing 100049 China Research Center of Geotechnical and Structural Engineering Shandong University Jinan 250100 China

The stability of rock slope is often controlled by the existing discontinuous surfaces, such as discrete fractures, which are ubiquitously distributing in a geological medium. In contrast with the traditional approaches used in soil slope with a continuous assumption, the simulation methods of jointed rock slope are different from that of in soil slope. This paper presents a study on jointed rock slope stability using the proposed discontinuous approach, which considers the effects of discrete fractures. Comparing with traditional methods to model fractures in an implicit way, the presented approach provides a method to simulate fractures in an explicit way, where grids between rock matrix and fractures are independent. To complete geometric components generation and mesh partition for the model, the corresponding algorithms were devised. To evaluate the stability state of rock slope quantitatively, the strength reduction method was integrated into our analysis framework. A benchmark example was used to verify the validation of the approach. A jointed rock slope, which contains natural fractures, was selected as a case study and was simulated regarding the workflow of our framework. It was set up in the light of the geological condition of the site. Slope stability was evaluated under different loading conditions with various fracture patterns. Numerical results show that fractures have significant contributions to slope stability, and different fracture patterns would lead to different shapes of the slip surface. The devised method has the ability to calculate a non-circular slip surface, which is different from a circular slip surface obtained by classical methods.

关键词： Rock slope stability Discrete fractures Discontinuous approach Equivalent model Slip surface

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定向电场下W_(6)C_(6)团簇的超卤素调制及非线性光学特性

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原子与分子物理学报 2025年第3期42卷 72-76页

作者：蔡璧钧段宇静魏强重庆理工大学理学院重庆400050

本文采用密度泛函(DFT)方法研究了定向外电场(OEEF)对W_(6)C_(6)团簇几何结构、电子性质以及非线性光学响应(NLO)的影响.计算结果表明W_(6)C_(6)的结构在一定OEEF强度下可以保持稳定.OEEF可以增大W_(6)C_(6)团簇的电子亲和能(EA值),且... 详细信息

本文采用密度泛函(DFT)方法研究了定向外电场(OEEF)对W_(6)C_(6)团簇几何结构、电子性质以及非线性光学响应(NLO)的影响.计算结果表明W_(6)C_(6)的结构在一定OEEF强度下可以保持稳定.OEEF可以增大W_(6)C_(6)团簇的电子亲和能(EA值),且在特定强度下,OEEF可以将W_(6)C_(6)团簇转变为超卤素.通过对EA值的非线性拟合可以实现对W_(6)C_(6)团簇的连续调制.进一步对不同外电场下W_(6)C_(6)团簇的最高占据分子轨道(HOMO)和最低未占据分子轨道(LUMO)能级进行分析,发现OEEF降低了W_(6)C_(6)团簇LUMO能级是其EA值增大的主因.此外,OEEF可以显著增大W_(6)C_(6)团簇的平均极化率和第一超极化率,尤其是第一超极化率,改变其非线性光学性质.

关键词：定向外电场超原子密度泛函理论 NLO W_(6)C_(6)团簇

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