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Acta Geochimica 2024年第3期43卷 441-458页

作者： Qing-Qing Zhang you-wei Chen Jian-Feng Gao State Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China University of Chinese Academy of Sciences Beijing 100049China

The Xingluokeng deposit is the largest gran-ite-related tungsten deposit within the Wuyi metallogenic belt in South *** Xingluokeng intrusion primarily consists of porphyritic biotite granite,biotite granite,andfine-grained *** deposit is represented by veinlet-disseminated mineralization with K-feldspathization and biotitization,alongside quartz-vein mineralization with gre-isenization and *** study investigates in-situ analyses of quartz compositions from both the intrusion and hydrothermal veinlets and *** element correlations indicate that trivalent Al^(3+)and Fe^(3+)replace si^(4+)within the quartz lattice,with monovalent cations(such as Li^(+),Na^(+),and K^(+))primarily serving as charge *** Ge/Al ratios(sit.

关键词： Quartz Xingluokeng Tungsten deposit Trace elements South China

Extreme value theory applied to the auroral electrojet indices

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Earth and Planetary Physics 2024年第2期8卷 375-381页

作者： si Chen Hong Yuan Yong wei Guang Yang FengZheng Yu Aerospace Information Research Institute Chinese Academy of SciencesBeijing 100094China Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China

The study of extreme weather and space events has gained paramount importance in modern society owing to rapid advances in high *** and describing exceptional occurrences plays a crucial role in making decisive assessments of their potential impact on technical,economic,and social aspects in various *** research focuses on analyzing the hourly values of the auroral electrojet(AE)geomagnetic index from 1957 to 2019 by using the peak over threshold method in extreme value *** fitting the generalized Pareto distribution to extreme AE values,shape parameter indices were derived,revealing negative values that establish an upper bound for this time ***,it became evident that the AE values had reached a plateau,suggesting that extreme events exceeding the established upper limit are *** a result,although the need for diligent precautions to mitigate the consequences of such extreme events persists,surpassing the upper limit of AE values becomes increasingly *** is also possible to observe an aurora in the middle-and low-latitude regions during the maximum period of the AE index.

关键词： auroral electrojet indices extreme value theory extreme events

Unraveling the biological link between diabetes mellitus and prostate cancer:Insights and implications

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World Journal of Diabetes 2024年第6期15卷 1367-1373页

作者： Jian Li Zhi-Peng Li si-si Xu wei Wang Department of Interventional Oncology Municipal Hospital Affiliated to Taizhou UniversityTaizhou 318000Zhejiang ProvinceChina School of Medicine Taizhou UniversityTaizhou 318000Zhejiang ProvinceChina

This article is a comprehensive study based on research on the connection between diabetes mellitus(DM)and prostate cancer(PCa).It investigates the potential role of DM as an independent risk factor for PCa,delving into the biological links,including insulin resistance and hormonal *** paper critically analyzes previous studies that have shown varying results and introduces mendelian randomization as a method for establishing *** emphasizes the importance of early DM screening and lifestyle modifications in preventing PCa,and proposes future research directions for further understanding the DM-PCa relationship.

关键词： Biological mechanisms Diabetes mellitus Mendelian randomization Prevention prostatic cancer Treatment

Viscoacoustic generalized screen propagator in constant-Q model

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Petroleum Science 2024年第4期21卷 2356-2369页

作者： Zhong-Kui Dai Jia-Chun you Xing-Guo Huang wei Liu College of Geophysics Chengdu University of Technology College of Instrumentation and Electrical Engineering Jilin University

When seismic waves propagate through the geological formation, there is a significant loss of energy and a decrease in imaging resolution, because of the viscoacoustic properties of subsurface medium. This profoundly impacts seismic wavefield propagation, imaging and interpretation. To accurately image the true structure of subsurface medium, the consensus among geophysicists is to no longer treat subsurface medium as ideal homogeneous medium, but rather to incorporate the viscoacoustic properties of subsurface medium. Based on the generalized screen propagator using conventional acoustic wave equation(acoustic GSP), our developed method introduces viscoacoustic compensation strategy, and derives a one-way wave generalized screen propagator based on time-fractional viscoacoustic wave equation(viscoacoustic GSP). In numerical experiments, we conducted tests on two-dimensional multi-layer model and the Marmousi model. When comparing with the acoustic GSP using the acoustic data, we found that the imaging results of the viscoacoustic GSP using the viscoacoustic data showed a significant attenuation compensation effect, and achieved imaging results for both algorithms were essentially consistent. However, the imaging results of acoustic GSP using viscoacoustic data showed significant attenuation effects, especially for deep subsurface imaging. This indicates that we have proposed an effective method to compensate the attenuated seismic wavefield. Our application on a set of real seismic data demonstrated that the imaging performance of our proposed method in local areas surpassed that of the conventional acoustic GSP. This suggests that our proposed method holds practical value and can more accurately image real subsurface structures while enhancing imaging resolution compared with the conventional acoustic GSP. Finally, with respect to computational efficiency, we gathered statistics on running time to compare our proposed method with conventional Q-RTM, and it is evid

关键词： One-way wave equation Viscoacoustic wave equation Generalized screen propagator Attenuation and dispersion effects

Geometry and formation mechanism of tension gashes and their implication on the hydrocarbon accumulation in the deep-seated strata of sedimentary basin:A case from Shunnan area of Tarim Basin

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Petroleum Science 2024年第1期21卷 87-99页

作者： Yan-Nan Du Kong-you Wu Yin Liu Yan-Ying Li Zi-Cheng Cao you-wei Cui Jun Liu Key Laboratory of Deep Oil and Gas School of GeosciencesChina University of Petroleum(East China)Qingdao 266580ShandongChina Exploration and Development Research Institute SINOPEC Northwest Oilfield BranchUrumqi 830011XinjiangChina The Fifth Gas Production Plant Changqing OilfieldPetroChinaXi'an 710018ShaanxiChina

With the theoretical and technological developments related to cratonic strike-slip faults,the Shuntuoguole Low Uplift in the Tarim Basin has attracted considerable attention *** by multi-stage tectonic movements,the strike-slip faults have controlled the distribution of hydrocarbon resources owing to the special fault characteristics and fault-related *** contrast,the kinematics and formation mechanism of strike-slip faults in buried sedimentary basins are difficult to investigate,limiting the discussion of these faults and hydrocarbon *** this study,we identified the characteristics of massive sigmoidal tension gashes(STGs)that formed in the Shunnan area of the Tarim ***-resolution three-dimensional seismic data and attribute analyses were used to investigate their geometric and kinematic ***,the stress state of each point of the STGs was calculated using seismic curvature ***,the formation mechanism of the STGs and their roles in controlling hydrocarbon migration and accumulation were *** results suggest that:(1)the STGs developed in the Shunnan area have a wide distribution,with a tensile fault arranged in an enéchelon pattern,showing an S-shaped *** STGs formed in multiple stages,and differential rotation occurred along the direction of strike-slip stress during formation.(2)Near the principal displacement zone of the strike-slip faults,the stress value of the STGs was higher,gradually decreasing at both *** shallow layer deformation was greater than the deep layer deformation.(3)STGs are critical for connecting source rocks,migrating oil and gas,sealing horizontally,and developing efficient *** study not only provides seismic evidence for the formation and evolution of super large STGs,but also provides certain guidance for oil and gas exploration in this area.

关键词： Tarim Basin sigmoidal tension gashes Seismic attributes Shear stress calculation Formation mechanism Reservoir control

Deterministic processes drive turnover-dominated beta diversity of breeding birds along the central Himalayan elevation gradient

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Avian Research 2024年第2期15卷 163-171页

作者： Zhifeng Ding Jianchao Liang Le Yang Cong wei Huijian Hu Xingfeng si Guangdong Key Laboratory of Animal Conservation and Resource Utilization Institute of ZoologyGuangdong Academy of SciencesGuangzhouGuangdong510260China Tibet Plateau Institute of Biology Lhasa850001China Zhejiang Zhoushan Island Ecosystem Observation and Research Station Institute of Eco-ChongmingZhejiang Tiantong Forest Ecosystem National Observation and Research StationSchool of Ecological and Environmental SciencesEast China Normal UniversityShanghai200241China

Beta diversity,the variation of community composition among sites,bridges alpha and gamma diversity and can reveal the mechanisms of community assembly through applying distance-decay models and/or partitioning beta diversity into turnover and nestedness components from functional and phylogenetic *** as the most natural experiment system provide good opportunities for exploring beta diversity patterns and the underlying ecological ***,we simultaneously consider distance-decay models and multiple di-mensions of beta diversity to examine spatial variations of bird communities,and to evaluate the relative importance of niche-based and neutral community assembly mechanisms along a 3600-m elevational gradient in the central Himalayas,*** results showed that species turnover dominates taxonomic,functional,and phylogenetic beta *** observed strongest evidence of spatial distance decays in taxonomic similarities of birds,followed by its phylogenetic and functional *** component was highest in taxonomic beta diversity,while nestedness component was highest in functional beta ***,all correlations of assemblage similarity with climatic distance were higher than that with spatial *** values of overall taxonomic,functional,and phylogenetic beta diversity and their turnover components increase with increasing elevational distance,while the standardized values of taxonomic and phylogenetic nestedness decreased with increasing elevational *** results highlighted the niche-based deterministic processes in shaping elevational bird diversity patterns that were determined by the relative roles of decreasing trend of environmental filtering and increasing trend of limiting similarity along elevation distances.

关键词： Beta diversity Bird Community assembly Functional trait Himalaya Nestedenss Phylogenetic distance Turnover

Study of baryon number transport dynamics and strangeness conservation effects using Ω-hadron correlations

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Nuclear Science and Techniques 2024年第7期35卷 147-156页

作者： wei-Jie Dong Xiao-Zhou Yu si-Yuan Ping Xia-Tong Wu Gang Wang Huan-Zhong Huang Zi-wei Lin Key Laboratory of Nuclear Physics and Ion-beam Application(MOE) Fudan UniversityShanghai 200433China Department of Physics and Astronomy University of CaliforniaLos AngelesCA 90095USA Department of Physics East Carolina UniversityGreenvilleNC 27858USA

In nuclear collisions at RHIC energies, an excess of Ω hyperons over ■ is observed, indicating that Ω has a net baryon number despite s and s quarks being produced in pairs. The baryon number in Ω may have been transported from the incident nuclei and/or produced in the baryon-pair production of Ω with other types of anti-hyperons such as Ξ. To investigate these two scenarios, we propose to measure the correlations between Ω and K and between Ω and anti-hyperons. We use two versions, the default and string-melting, of a multiphase transport(AMPT) model to illustrate the method for measuring the correlation and to demonstrate the general shape of the correlation. We present the Ω-hadron correlations from simulated Au+Au collisions at ■ =7.7 and 14.6 Ge V and discuss the dependence on the collision energy and on the hadronization scheme in these two AMPT versions. These correlations can be used to explore the mechanism of baryon number transport and the effects of baryon number and strangeness conservation on nuclear collisions.

关键词： Baryon number transport Strangeness conversation Correlation Gluon junction

Dynamical switchable quantum nonreciprocity induced by off-resonant chiral two-photon driving

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Science China(Physics,Mechanics & Astronomy) 2024年第6期67卷 31-37页

作者： Da-wei Liu Zi-Hao Li Shi-Lei Chao Ying Wu Liu-Gang si School of Physics and Institute for Quantum Science and Engineering Huazhong University of Science and TechnologyWuhan 430074China

Optical nonreciprocity,which refers to the direction-dependent emission,scattering and absorption of photons,plays a very important role in quantum engineering and quantum information ***,we propose an all-optical approach to achieve the optical dynamical switchable quantum nonreciprocity by an off-resonant chiral two-photon driving in a single microring cavity,which differs from the conventional nonreciprocal *** is shown that the optical field with time-dependent statistical properties can be generated and the nonreciprocity flips periodically,with switchable photon blockade and photon-induced tunneling *** find that the dynamical system is robust and immune to the parameter variations,which loosens the parameter range of ***,the time window for one-way quantum information is sufficiently wide and *** work opens a new idea for the current quantum nonreciprocal research,which can facilitate a memory functionality and be used for future inmemory superconducting quantum *** other nonreciprocal quantum devices,i.e.,dynamical switchable nonreciprocal squeezing and entanglement,may be inspired by our method,which is expected to have important applications in future quantum technology.

关键词： dynamical switchable nonreciprocity single-photon source chiral two-photon driving

Beam based alignment using a neural network

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Nuclear Science and Techniques 2024年第4期35卷 108-118页

作者： Guan-Liang Wang Ke-Min Chen si-wei Wang Zhe Wang Tao He Masahito Hosaka Guang-Yao Feng wei Xu National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei 230029China Diamond Light Source Oxfordshire OX110DEUK

Beams typically do not travel through the magnet centers because of errors in storage *** beam deviating from the quadrupole centers is affected by additional dipole fields due to magnetic field ***-based alignment(BBA)is often performed to determine a golden orbit where the beam circulates around the quadrupole center *** storage rings with many quadrupoles,the conventional BBA procedure is time-consuming,particularly in the commissioning phase,because of the necessary iterative *** addition,the conventional BBA method can be affected by strong coupling and the nonlinearity of the storage ring *** this study,a novel method based on a neural network was proposed to determine the golden orbit in a much shorter time with reasonable *** golden orbit can be used directly for operation or adopted as a starting point for conventional *** method was demonstrated in the HLS-II storage ring for the first time through simulations and online *** results of the experiments showed that the golden orbit obtained using this new method was consistent with that obtained using the conventional *** development of this new method and the corresponding experiments are reported in this paper.

关键词： Golden orbit Beam-based alignment Neural network Storage ring

Well-controlled Organocatalytic Ring-opening Polymerization of Seven-membered Cyclic Carbonates with Cyclohexyl Fusion

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CHEMICAL RESEARCH IN CHINESE UNIVERsiTIES 2024年第5期40卷 856-862页

作者： Zhang, wei Shan, si-Yi Dai, Jiang Cai, Zhongzheng Zhu, Jian-Bo Tianjin Univ Sci & Technol Coll Chem Engn & Mat Sci Tianjin Key Lab Brine Chem Engn & Resource Ecoutil Tianjin 300457 Peoples R China sichuan Univ Coll Chem Natl Engn Lab Ecofriendly Polymer Mat Sichuan Chengdu 610064 Peoples R China

Developing green and well-controlled polymerization methods is of great significance for the preparation of biomedical polymer materials. In this contribution, an efficient organocatalytic ring-opening polymerization (ROP) of a class of seven-membered cyclic carbonates (T6DO, T6HDO, C6DO, C6HDO) containing cis- or trans-cyclohexane structure was established. Organic catalyst 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD) promoted living polymerization of these cyclic carbonates to deliver polycarbonate and block copolymer products with predictable molecular weights and narrow dispersity. The robust TBD-mediated ROP at 90 degrees C showcased turnover frequency (TOF) up to 10(3) h(-1). The resulting amorphous polycarbonates displayed good thermal stability.

关键词： CO2 Organic catalyst Living ring-opening polymerization Aliphatic polycarbonate KINETIC RESOLUTION POLYMERIZATION RAC-LACTIDE