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Cretaceous magmatic arc in Hainan and the peri-South China Sea asevidenced by geochemical fingerprinting of granitoids in the region

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Geoscience Frontiers 2024年第5期15卷 355-371页

作者： Xiao-Yan jiang Yildirim Dilek Xian-hua Li State Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Department of Geology and Environmental Earth Science Miami UniversityOxfordOH 45056USA

Mesozoic magmatic rocks occur widely in the South China Block and are generally interpreted as the manifestations of the subduction of the Paleo-Pacific oceanic lithosphere beneath *** magmatism in southeast(SE)China continued from the Late Permian through the Late Cretaceous with an inferred lull between 125 Ma and 115 Ma that is known in the literature as the Cretaceous"magmatic quiescence".We report in-situ zircon U-Pb ages,Hf-O and whole-rock Sr-Nd isotopes,and whole-rock geochemistry of Cretaceous granitoids on Hainan Island and discuss their magmatic evolution within the framework of the Late Mesozoic geodynamics of SE *** recognize two main stages of the emplacement of Cretaceous granitoids on Hainan,first around 120 Ma and then around 100-95 Ma,displaying high-K calc-alkaline,I-type geochemical *** in both age groups are enriched in LILE and LREE,but depleted in Nb,Ta,Ba,Sr,and *** 120 Ma granites have zircon ε_(Hf)(t)values of-2.6 to 2.3 corresponding to Hf crustal model ages,ranging from 0.79 Ga to 1.03 Ga,and δ^(18)O values ranging from 6.9‰to 7.7‰.Zircons from 100-95 Ma granites have ε_(Hf)(t)values of-4.2 to 1.1 corresponding to Hf crustal model ages of 1.08 Ga to 1.42 Ga,and δ^(18)O values ranging from 6.7‰to 8.4‰.Increasing ε_(Hf)(t)values of the Cretaceous Hainan granites with younger crystallization ages indicate addition of more juvenile components and reworking of crustal material into their melt *** ε_(Nd)(t)values of the 120 Ma and 100-95 Ma granitoids range between-4.1 to-0.4 and-7.7 to-4.0,*** calculated two-stage model age of the 100-95 Ma granitoids clusters between 1.25 Ga and 1.53 *** isotopic data suggest that magmas of the Cretaceous granitoids were produced by partial melting of Mesoproterozoic metabasaltic rocks,which make up much of the crystalline basement of the southern Cathaysia *** geochemical and isotopic characteristics of the Cretaceous granitoids on H

关键词： I-type granites Cretaceous Hainan Island Southeast China Magmatic arc peri-South China Sea region

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(Parallel) kinetic resolution of 3,3-disubstituted indolines via organocatalyzed reactions with azodicarboxylates

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Science China Chemistry 2024年第3期67卷 973-980页

作者： Qianwen jiang Dekun Zhang Mengyao Tang hua Liu Xiaoyu Yang School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China

A novel kinetic resolution(KR) method has been developed for 3,3-disubstituted indolines, whose catalytic asymmetric synthesis remains a significant challenge in organic synthesis. The key to the success of this KR protocol lies in the utilization of chiral phosphoric acid-catalyzed triazane formation reaction with azodicarboxylates, which enables the enantioselective synthesis of various substituted indolines bearing C3-quaternary stereocenters with good to high enantioselectivities(with sfactors up to 70). Moreover, an intriguing parallel kinetic resolution(PKR) has been developed by combining triazane formation and dehydrogenation reactions using different azodicarboxylates. Experimental studies have provided insight into the mechanism of this PKR reaction, demonstrating stereoselectivity in both triazane formation and dehydrogenation steps, favoring the opposite enantiomers. The large-scale synthesis and diverse derivatizations of the products, particularly the imine groupcontaining 3H-indoles, demonstrate the value of these(P)KR methods.

关键词： asymmetric organocatalysis kinetic resolution 3 3-disubstituted indolines azodicarboxylate triazanes

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Multifunctional phase change film with high recyclability, adjustable thermal responsiveness, and intrinsic self-healing ability for thermal energy storage

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Journal of Energy Chemistry 2024年第10期97卷 216-227,I0005页

作者： Bo Yang Xuelai Zhang Jun Ji Weisan hua Miaomiao jiang Institute of Cool Thermal Storage Technology Shanghai Maritime UniversityShanghai 201306China

Phase change materials(PCMs) present promising potential for guaranteeing safety in thermal management ***,most reported PCMs have a single application in energy storage for thermal management systems,which does not meet the growing demand for multi-functional *** this paper,the flexible material and hydrogen-bonding function are innovatively combined to design and prepare a novel multi-functional flexible phase change film(PPL).The 0.2PPL-2 film exhibits solid-solid phase change behavior with energy storage density of 131.8 J/g at the transition temperature of42.1℃,thermal cycling stability(500 cycles),wide-temperature range flexibility(0-60℃) and selfhealing ***,the PPL film can be recycled up to 98.5% by intrinsic ***,the PPL film can be tailored to the desired colors and configurations and can be cleverly assembled on several thermal management systems at ambient temperature through its flexibility combined with shape-memory *** interestingly,the transmittance of PPL will be altered when the ambient temperature changes(60℃),conveying a clear thermal ***,the thermal energy storage performance of the PPL film is successfully tested by human thermotherapy and electronic device temperature control *** proposed functional integration strategy provides innovative ideas to design PCMs for multifunctionality,and makes significant contributions in green chemistry,highefficiency thermal management,and energy sustainability.

关键词： Phase change film Multifunctional material Energy storage Self-healing Recyclability

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Prevalence and clinical impact of sarcopenia in liver transplant recipients:A meta-analysis

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World Journal of Gastroenterology 2024年第8期30卷 956-968页

作者： Min-Jie jiang Mu-Chen Wu Zhong-Hui Duan jing Wu Xiao-Tong Xu Juan Li Qing-hua Meng Department of Hepatology Beijing You-An HospitalCapital Medical UniversityBeijing 100069China Department of Emergency Beijing You-An HospitalCapital Medical UniversityBeijing 100069China

BACKGROUND The prevalence of sarcopenia in patients undergoing liver transplantation(LT)remains to be determined partly because of different diagnostic *** has recently been recognized as a new prognostic factor for predicting outcomes in LT *** To estimate the prevalence of sarcopenia and evaluate its clinical effect on LT *** This systematic search was conducted in PubMed,Web of Science,Embase,and Cochrane Library for original English-language articles that investigated the prevalence and influence of sarcopenia in patients undergoing LT from database inception to November 30,*** studies of the definition of sarcopenia that estimate sarcopenia prevalence and evaluate its effect on clinical outcomes and the risk of mortality were *** Twenty-five studies involving 7760 patients undergoing LT were *** pooled prevalence of sarcopenia in patients undergoing LT was 40.7%[95%confidence intervals(95%CI):32.1-49.6].The 1-,3-,and 5-year cumulative probab-ilities of post-LT survival in patients with preoperative sarcopenia were all lower than those without sarcopenia(P<0.05).Sarcopenia was associated with an increased risk of post-LT mortality in patients undergoing LT(adjusted hazard ratio:1.58;95%CI:1.21-2.07).Patients with preoperative sarcopenia had a longer intensive care unit stay,a high risk ratio of sepsis,and serious post-LT complications than those without *** Sarcopenia is prevalent in a substantial proportion of patients undergoing LT and is strongly and independently associated with higher a risk of mortality risk.

关键词： Sarcopenia Liver transplantation Mortality Clinical outcomes

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Feasibility of medical radioisotope production based on the proton beams at China Spallation Neutron Source

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Nuclear Science and Techniques 2024年第6期35卷 26-39页

作者： Bing jiang Bin-Bin Tian Han-Tao jing Qi-Fan Dong Spallation Neutron Source Science Center Dongguan 523803China Institute of High Energy Physics Chinese Academy of Sciences(CAS)Beijing 100049China University of Chinese Academy of Sciences Beijing 100049China

The utilization of a proton beam from the China Spallation Neutron Source(CSNS)for producing medical radioisotopes is appealing owing to its high current intensity and high *** medical isotope production based on the proton beam at the CSNS is significant for the development of future radiopharmaceuticals,particularly for theα-emitting *** production yield and activity of typical medical isotopes were estimated using the FLUKA *** results indicate that the 300-MeV proton beam with a power of 100 kW at CSNS-II is highly suitable for proof-of-principle studies of most medical *** particular,this proton beam offers tremendous advantages for the large-scale production of alpha radioisotopes,such as 225Ac,whose theoretical production yield can reach approximately 57 Ci/*** on these results,we provide perspectives on the use of CSNS proton beams to produce radioisotopes for medical applications.

关键词： CSNS proton beam Medical isotope production α-Emitting radionuclides Nuclidic purity analysis

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Effects of hot deformation and in-situ ZrB2 particle on microstructure and tensile performance of AA7085 composite sheets

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Journal of Iron and Steel Research International 2024年第7期31卷 1778-1791页

作者： jiang-jing Wu Xi-zhou Kai Chuang Guan Yu-tao Zhao School of Material Science and Engineering Jiangsu UniversityZhenjiang 212013JiangsuChina

To provide a new idea to reduce anisotropy for sheets in the thickness direction by microstructure modification and,mean-while,maintain or even enhance tensile performance,the in-situ ZrB2 particle/AA7085 composite sheets with thicknesses of 1,2,3,and 6 mm were *** as-cast grain size was significantly refined by the heterogeneous nucleus of the ZrB2 *** microstructure results show that severe hot deformation converts as-cast disordered microstructure into a sequential microstructure by crushing the remanent phases and matrix into a fiber *** the solid solution and aging heat treatment,the composite sheets exhibit largely recrystallized grains compared with partially recrystallized grains in the matrix sheets,and weak or even free texture exists in the *** grain size in the composite sheets decreases with the increase in thickness *** the thickness range of 1-3 mm,the composite sheets maintain a similar tensile per-formance as that in matrix sheets,while the strength and ductility in the 6-mm-thick composite sheet are improved.

关键词： Composite sheet Grain structure Texture Dislocation Strengthening

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Prediction of chemical short-range order in high-/medium-entropy alloys

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Journal of Materials Science & Technology 2024年第2期169卷 115-123页

作者： Pei-Yu Cao jing Wang Ping jiang Yun-jiang Wang Fu-Ping Yuan Xiao-Lei Wu State Key Laboratory of Nonlinear Mechanics Institute of MechanicsChinese Academy of ScienceBeijing 100190China School of Engineering Science University of Chinese Academy of SciencesBeijing 100049China

Chemical short-range orders(CSROs),as the built-in sub-nanoscale entities in a high-/medium-entropy alloy(H/MEA),have aroused an ever-increasing *** multi-principal elements in an H/MEA to form a complex concentrated solution,a variety of sub-systems of species exist to induce the metastable ordered compounds as candidates for ultimate *** issues remain pending on the origin of CSROs as to how to judge if CSRO will form in an H/MEA and particularly,what kind of CSROs would be stably produced if there were multiple ***,the first-principles method,along with the proposed local formation energy calculation in allusion to the atomic-scale chemical heterogeneities,is used to predict the CSRO formation based on the mechanical stability,thermodynamic formation energy,and electronic *** simulations are detailed in an equiatomic ternary VCoNi MEA with three kinds of potential compounds,i.e.,L1_(1),L1_(2),and B2,in the face-centered cubic *** turns out that L1_(1)is stable but hard to grow up so as to become the final CSRO.L1_(1)is further predicted as CSROs in CrCoNi,but unable to form in FeCoNi and CrMnFeCoNi *** predictions are consistent with the experimental *** findings shed light on understanding the formation of *** method is applicable to other H/MEAs to design and tailor CSROs by tuning chemical species/contents and thermal processing for high performance.

关键词： Short-range order High-entropy alloy Microstructure First-principles calculation Gibbs free energy Local electronic density of states

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Current status of Mycoplasma pneumoniae infection in China

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World Journal of Pediatrics 2024年第1期20卷 1-4页

作者： Chao Yan Guan-hua Xue Han-Qing Zhao Yan-Ling Feng jing-hua Cui jing Yuan Department of Bacteriology Capital Institute of PediatricsNo.2Yabao RoadBeijing 100020People's Republicof China

Mycoplasma pneumoniae(***)is one of the most important pathogens for community-acquired pneumonia worldwide,especially in children and adolescents[1,2].*** is easily transmitted through droplets or direct contact in densely populated,enclosed,or poorly ventilated *** incubation period is 1-3 weeks,and it is contagious from the incubation period to a few weeks after clinical symptom *** infection can occur in any season,and there are differences in the epidemic seasons among regions in China[3].The most suitable culture temperature for *** is between 35℃C and 37 C,and therefore,hot weather may make it survive longer in the environment and spread *** is more common in autumn and winter in northern China,while it is more prevalent in summer and autumn in southern China.

关键词： winter weather autumn

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Garnet and Zircon U-Pb Geochronology and Geochemistry Reveal Genesis of the Dafang Au-Pb-Zn-Ag Deposit,Southern Hunan

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Acta Geologica Sinica(English Edition) 2024年第3期98卷 717-735页

作者： jiang hua KONG hua LIU Biao TAN Fucheng QIN Yixue huaNG jingang ZHU Yu Key Laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitoring Ministry of EducationSchool of Geosciences and Info-PhysicsCentral South UniversityChangsha 410083China School of Geosciences and Info-Physics Central South UniversityChangsha 410083China Hunan Baoshan Nonferrous Metals and Minerals Co. Ltd.ChenzhouHunan 424402China

Garnet is a primary mineral in skarn deposits and plays a significant role in recording copious mineralization and metallogenic *** study systematically investigates the geochemistry and geochronology of garnet and zircon in the Dafang Au-Pb-Zn-Ag deposit,which represents prominent gold mineralization in southern Hunan,*** samples with distinct zoning patterns and compositional variations were identified using various analytical techniques,including Backscattered Electron(BSE)imaging,Cathodoluminescence(CL)response,textural characterization,and analysis of rare-earth elements(REE),major contents,and trace element *** garnet was dated U-Pb dating,which yielded a lower intercept age of 161.06±1.93 *** age is older than the underlying granodiorite porphyry,which has a concordia age of 155.13±0.95 Ma determined by zircon U-Pb *** results suggest that the gold mineralization may be related to the concealed *** groups of garnet changed from depleted Al garnet to enriched Al garnet,and the rare earth element(REE)patterns of these groups were converted from light REE(LREE)-enriched and heavy REE(HREE)-depleted with positive europium(Eu)anomalies to medium REE(MREE)-enriched from core to rim *** different REE patterns of garnet in various zones may be attributed to changes in the fluid environment and late superposition *** development of distal skarn in the southern Hunan could be a significant indicator for identifying gold mineralization.

关键词： garnet and zircon U-Pb dating LA-ICP-MS mapping Dafang Southern Hunan

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Microstructure evolution of Ti_(48)Zr_(27)Cu_(6)Nb_(5)Be_(14)amorphous alloy after semi-solid isothermal treatment

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China Foundry 2024年第3期21卷 287-294页

作者： Xin-hua huang jing-wen Pu Yong-xin Luo Yue-jun Ouyang School of Material Electricity and Intelligent ManufacturingHuaihua UniversityHuaihua 330031HunanChina Hunan Renewable Aluminum Innovation Research Center Huaihua UniversityHuaihua 330031HunanChina

The as-cast amorphous Ti_(48)Zr_(27)Cu_(6)Nb_(5)Be_(14)composites,comprising in situ formedβ-Ti ductile crystalline precipitates,were prepared by water cooled copper mold suction ***,the semi-solid composites were obtained after the as-cast composites were treated by semi-solid isothermal *** microstructure evolution and kinetics of the composites were *** show that the microstructures of both the as-cast and semi-solid composites comprise ofβ-Ti crystal phases and amorphous matrix *** and after treatment,the crystals evolve from fine granular or fine dendritic crystals to coarse *** the treatment temperature increasing or the time prolonging,the average crystal size gradually increases and the surface morphology of the crystals gradually becomes *** studying the microstructural evolution and dynamics during the isothermal treatment process,it is found that the final morphology ofβ-Ti crystals is influenced by the isothermal treatment temperature and time(t),and theβ-Ti evolution rate increases with an increase in treatment *** addition,a linear relationship was observed between the size of cubicβ-Ti crystals(D^(3))and t;the growth kinetics factor K is 3.8μm^(3)·s^(-1).As the K value closes to 4μm^(3)·s^(-1),it is inferred the morphology evolution ofβ-Ti crystals is a coarsening behavior controlled by the diffusion of solute elements.

关键词： Ti_(48)Zr_(27)Cu_(6)Nb_(5)Be_(14) amorphous matrix composites semi-solid as-cast microstructure

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