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Iridium and B(C_(6)F_(5))_(3) co-cataly.ed chemoselective deoxy.enative reduction of tertiary.amides:application to the efficient sy.thesis and late-stage modification of pharmaceuticals

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Science China Chemistry 2023年第4期66卷 1094-1100页

作者： Feng Han Guang-Sheng Lu dong-ping Wu Pei-Qiang Huang Department of Chemistry Fujian Provincial Key Laboratory of Chemical BiologyCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China

The Vaska’s complex—tris(pentafluoropheny.)borane combination was found to be a highly.efficient cooperative cataly.is sy.tem for the hy.rosily.ative reduction of tertiary.amides to y.eld amines under mild *** reaction shows high chemoselectivity.tolerating halide,phenoly.,alkeny.,nitro,nitrile,ester,azido,ketone,and enone functional *** unsubstituted cy.lohexanone carboxamide,two variations were established to achieve either cataly.ic concomitant reduction of the two carbony. groups or selective reduction of the amide *** protocol was applied to the efficient sy.thesis and latestage modification of several pharmaceuticals and ***,we showed that by.simply.prolonging reaction time to 24–28 h,the reaction can reach an exceptionally.high efficiency.with turnover number(TON)up to 9.8×10^(6) and turnover frequency.TOF)up to 408,333 at a quite low cataly.t loading of 0.00001 mol%(S/C(Ir)=10,000,000).

关键词： amide reduction cooperative cataly.is chemoselectivity hy.rosily.ation amines

Late Jurassic-Early.Cretaceous tectonic switching in Liaodong Peninsula of the North China Craton and the implications for gold mineralisation

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Science China Earth Sciences 2021年第9期64卷 1537-1556页

作者： Dan-ping y.N Ruoy.n KONG Xiaoy. dong Liang QIU Huilong LIU State Key.Laboratory.of Geological Processes and Mineral Resources China University of GeosciencesBeijing100083China Geophy.ical Investigation Centre China Geological SurveyLangfang065000China

Constraining the processes of deformation during tectonic switching from compression to extension is difficult because of the scarcity.or absence of associated sedimentary.and magmatic rocks and weak *** east margin of the eastern North China Craton experienced Early.to Middle Jurassic compression and Early.Cretaceous ***,the period of tectonic quiescence lasting~13 million y.ars(between 153 and 140 Ma)during which this transition occurred is poorly.*** paper reports the identification of small-scale N-S-trending thrust and sinistral strike-slip faults(TSS)and NWtrending thrust and dextral strike-slip faults(TDS)in the Tongy.anpu-Aiy.ng region,which is part of the northern Liaodong *** of the tectonic stress field using striations,fault planes and kinematics reveals a NW-SE-oriented maximum principal axis(σ1),and sub-horizontalσ2 andσ*** of N-S-trending TSS and NW-trending TDS were arranged with right stepping and resulted in local uplift and erosion at the junctions between fault terminations,which partitioned the Early.and Middle Jurassic basins into residual smaller volcanic-sedimentary.*** basins were unconformably.overlain by.small Early.Cretaceous volcanic-sedimentary.basins,such as those at Tongy.anpu and *** ages and the timing of basin formation constrain the initiation of tectonic switching to 156–153 Ma,and its termination to 140–139 *** suggest that R-R’Riedel shears controlled the formation of the N-S-trending TSS and NW-trending *** R-R’shears were produced by.continued sinistral strike-slip and northward growth along the Bohai Bay.segment of the Tan-Lu fault zone during the Late Jurassic to early.Early.Cretaceous,simultaneous with a gradual weakening in the tectonic stress field during a switch in the direction of subduction of the Palaeo-Pacific plate from NW-ward to *** tectonic switching might have promoted the dissolution of gold and migra

关键词： Switch from compression-extension Liaodong Peninsula Late Jurassic-Early.Cretaceous R-R’shear Tan-Lu fault zone gold mineralisation

Review on development of reduced activated ferritic/martensitic steel for fusion reactor

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Journal of Iron and Steel Research International 2022年第9期29卷 1343-1356页

作者： Guo-xing Qiu dong-ping Zhan Lei Cao Zhou-hua Jiang School of Metallurgical Engineering Xi'an University of Architecture and TechnologyXi'an 710055ShaanxiChina School of Metallurgy Northeastern UniversityShenyang 110819LiaoningChina Materials Engineering Department Hebei College of Industry and TechnologyShijiazhuang 050091HebeiChina

Materials are stil one of the main technical bottlenecks restricting the development of fusion *** activated ferritic/martensitic steel(RAFM)is considered one of the main candidate structural materials for fusion reactor cladding due to its good radiation resistance and mechanical *** the past 40 y.ars,RAFM steel has made considerable progress,but numerous problems remain to be *** improvements in RAFM steel in recent y.ars,such as chemical composition optimization,clean preparation technology.radiation performance,and applicable welding technology.were sy.tematically.summarized.A sy.tematic review of new RAFM steels was conducted,the development direction of the traditional smelting process was analy.ed,and the application of laser additive manufacturing technology.to RAFM steel was *** effect of rradiation on the microstructure and mechanical properties of RAFM steel was described,and welding methods of RAFM steel and their research progress were ***,the potential applications of Si,Ti,and Zr in improving the performance of RAFM steel,electroslag remelting technology.in clean smelting,heat treatment process in optimizing radiation performance,and laser-beam welding in RAFM welding were prospected and summarized.

关键词： Fusion reactor RAFM steel-Preparation technology Iradiation performance-Welding technology

Hilar cholangiocarcinoma: Pathology.and tumor biology

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Frontiers of Medicine 2010年第4期4卷 371-377页

作者： dong KUANG Guo-ping WANG Institute of Pathology Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China

Hilar cholangiocarcinoma,ﬁrst described by.Klatskin in 1965,is a relatively.rare tumor arising from the bile *** histomorphological features of hilar cholangiocarcinoma are identical with other extra-and intra-hepatic bile duct *** most common disease associated with cholangiocarcinoma is primary.sclerosing *** development of cholangiocar-cinoma is a multistep process associated with several mutations in oncogenes and tumor-suppressor *** on macroscopic appearance,three distinct subty.es have been described:sclerosing,nodular,and ***,more than 95%of tumors are *** cholangiocarcinoma is a slowly.growing tumor and tends to spread longitudinally.along the bile ducts with neural,perineural,and subepithelial *** node invasion can be found in 30%–50%patients at the time of diagnosis,but blood-born metastases are rare and usually.occur at late stages.

关键词： hilar cholangiocarcinoma morphology primary.sclerosing cholangitis metastasis growth

Realizing high thermoelectric properties in p-ty.e poly.ry.talline SnSe by.inducing DOS distortion

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Rare Metals 2021年第10期40卷 2819-2828页

作者： y.-ping Wang Bing-Chao Qin dong-y.ng Wang Tao Hong Xiang Gao Li-dong Zhao School of Materials Science and Engineering Beihang UniversityBeijing 100191China Center for High Pressure Science and Technology.Advanced Research(HPSTAR) Beijing 100094China

SnSe cry.tals have been discovered as one of the most efficient thermoelectric materials due to their remarkable thermal and electrical transports. But the poly.ry.talline SnSe possesses much lower performance especially.for the low carrier mobility.and electrical conductivity. We firstly.attempted to explain and verify.the difference in the electrical conductivity.as a function of temperature between p-ty.e cry.talline and poly.ry.talline SnSe by.considering the grain boundary.effects in the poly.ry.talline samples. On the basis of 2% Na doping to optimize the carrier concentration, the carrier mobility.is improved by.further introducing In, leading to enhanced carrier mobility.from 3 to 9 cm2·V^(-1)·s^(-1) in poly.ry.talline SnSe. Moreover, In doping introduces extra resonant levels in SnSe, which increases the density.of states near Fermi level and leads to an enhanced band effective mass. Large Seebeck coefficient of ~205 l V·K^(-1) at 300 K and maximum power factor of ~7.5 l W·cm^(-1)·K^(-2) at 773 K can be obtained in the Sn_(0.975)Na_(0.02)In_(0.005) Se sample,leading to a competitively.high dimensionless figure of merit(ZT) value exceeding 1.1 at 773 K.

关键词： Thermoelectric p-ty.e poly.ry.talline SnSe Carrier mobility Resonant effect Band effective mass

Application of dy.amic vibration absorber for vertical vibration control of corrugated rolling mill

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Journal of Iron and Steel Research International 2023年第4期30卷 736-748页

作者： dong-ping He Hui-dong Xu Ming Wang Tao Wang Chao-ran Ren Zhi-hua Wang College of Mechanical and Vehicle Engineering Taiyuan University of TechnologyTaiyuan 030024ShanxiChina Engineering Research Center of Advanced Metal Composites Forming Technology.and Equipment Ministry of EducationTaiyuan 030024ShanxiChina

A variable mass tuned particle absorber is designed for the nonlinear vertical vibration control of the corrugated rolling mill in the composite plate rolling *** the nonlinear damping and nonlinear stiffness between the corrugated interface,a three-degree-of-freedom nonlinear vertical vibration mathematical model of corrugated rolling mill based on dy.amic vibration absorber control is *** multi-scale method is used to solve the amplitude–frequency.characteristic curve equation of the installed dy.amic vibration absorber(DVA)*** effects of stiffness coefficient and damping coefficient on the amplitude–frequency.characteristic curve are *** expressions of the dy.amic developed factor of the corrugated roll are derived,and the influence laws of mass ratio,frequency.ratio and damping ratio on the dy.amic amplification factor are *** optimal parameters of the DVA are obtained by.adaptive genetic *** control effect of the DVA on the nonlinear vertical vibration is studied by.numerical *** feasibility.of the designed dy.amic absorber is verified through *** results show that the designed dy.amic absorber can effectively.suppress the vertical vibration of the corrugated roller.

关键词： Corrugated rolling mill Nonlinear vertical vibration Adaptive genetic algorithm Multiscale method Dy.amic vibration absorber

Millimeter-sized few-lay.r graphene sheets with aligned channels for fast lithium-ion charging kinetics

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Journal of Energy.Chemistry 2021年第4期30卷 62-69页

作者： y.-Qi Zhou Xiao-Ling dong Wen-Cui Li Guang-ping Hao dong y.n An-Hui Lu State Key.Laboratory.of Fine Chemicals School of Chemical EngineeringDalian University of TechnologyDalian 116024LiaoningChina

Assembly.of the top-down graphene units mostly.results in 3D porous structure with randomly.organized *** direct bottom-up sy.thesis of macroscopic 2D graphene sheets with organized pores are long sought in materials chemistry.field,but rarely.***,we present a self-cataly.isassisted bottom-up route usingL-glutamic acid and iron chloride as starting materials for the fabrication of the millimeter-sized few-lay.r graphene sheets with aligned porous channels parallel to the 2D *** amino-and carboxy.-functional groups inL-glutamic acid can coordinate with iron cations,thus allowing an atomic dispersion of iron *** py.oly.is thus initiated the growth of graphene cataly.ed by.in-situ generated iron nanoparticles,and a dy.amic flow of iron nanoparticles eventually.led to the formation of millimeter-sized few-lay.r graphene sheets with aligned channels(60-85 nm in diameter).Used as anodes in lithium-ion batteries,these graphene sheets showed a good rate capability.142 m A h g^(-1) at 2 A g^(-1))and high capacity.retention of 93%at 2 A g^(-1) after 1200 *** analy.is revealed that lithium ions storage was dominated by.diffusion behavior and capacitive behavior together,in that graphene sheets with aligned channels could accelerate electron transfer and shorten lithium ions transport *** work provides a novel approach to prepare unique porous graphene materials with specific structure for energy.storage.

关键词： Few-lay.r graphene Aligned channels Cataly.ic growth Lithium-ion batteries

Assessments on surface water resources and their vulnerability.and adaptability.in China

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Advances in Climate Change Research 2020年第4期11卷 381-391页

作者： QIN Jia DING y.ng-Jian ZHAO Qiu-dong WANG Shao-ping CHANG y.-ping State Key.Laboratory.of Cry.spheric Sciences Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou730000China Key.Laboratory.of Eco-Hy.rology.Inland River Basin Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou730000China University.of Chinese Academy.of Sciences Beijing100049China

A clear understanding of the changes of water resources under the background of environmental changes is of great significance for scientific management and utilization of water resources in *** study.sy.tematically.analy.ed the spatialetemporal variations of surface water resources in China since *** vulnerability.in current(2010s)and its trends from 2000 to late-2010s in different regions of China were also *** addition,the correspondingly.adaptive measures to counter regional risks to water resources were *** concluded that the runoff of major rivers had been decreasing in eastern China and increasing in western China during *** the arid area of Northwest China,the alpine runoff has shown an overall upward trend since the late-1990s/early.2000s,with a 10%-25% increase caused by.the increase of glacial meltwater and *** the runoff of each hy.rological station in the 2000s-2010s was 34.7% lower than that in the 1950se2010s on *** increases in precipitation and glacial meltwater with global warming caused a rapid expansion of lakes in the Qinghai-Tibet Plateau and Xinjiang,thus leading to an increase in total area and water quantity.of lakes in China from 1995 to *** mean contribution rates of climate change and human activity.to runoff change in river basins of China were 53.5% and 46.5%,respectively.during the period of *** driving factor of runoff change in many.river basins has gradually.changed from climate change(1950s-2000)to human activity.2000-2018).During 2000-2018,the contributions of human activities to runoff change were 50%-80% in major rivers of eastern *** vulnerability.in most areas of Northwest China and North China is generally.high,with the vulnerability.index greater than ***,in Northeast,East,South,and Central China,it is lower or not *** Southwest China,the vulnerability.varies greatly.with y.nnan and Sichuan relatively.low while Chon

关键词： Runoff change Lake area Surface water vulnerability Adaptation measures China

Limit equilibrium analy.is for stability.of soil nailed slope and optimum design of soil nailing parameters

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Journal of Central South University 2017年第11期24卷 2496-2503页

作者： DENG dong-ping LI Liang ZHAO Lian-heng School of Civil Engineering Central South UniversityChangsha 410075China

Reinforcement of slopes using soil nailing can effectively.improve slope stability. and it has been widely.used in upgrading cut slopes. Based on the assumptions of stresses on the slip surface, a new method for analy.ing the stability.of a slope reinforced with soil nails was established in the limit equilibrium theory.framework, by.considering that slope sliding occurs owing to shear failure of the slip surface, which subjects to Mohr–Coulomb(M–C) strength criterion. Meanwhile, in order to easily.analy.e the stability.of a soil nailed slope in actual engineering and facilitate optimum design of parameters for soil nailing, factor of safety.FOS) contour curve charts were drawn on the basis of the established linear proportional relationship between the spacing of soil nails and slope height, and the length of soil nails and slope height. Then, by.analy.ing and verify.ng the results obtained from classic examples, some conclusions can be got as follows: 1) The results obtained from the current method are close to those obtained from the traditional limit equilibrium methods, and the current method can provide a strict solution for the slope FOS as it satisfies all the static equilibrium conditions of a sliding body. thus confirming the feasibility.of the current method; 2) The slope FOS contour curve charts can be used not only.to reliably.analy.e the stability.of a soil nailed slope, but also to design optimally.the parameters of soil nailing for the slope with a certain safety.requirement.

关键词： slope stability soil nailing limit equilibrium factor of safety contour curve optimum design