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Science China(Physics,Mechanics & Astronomy) 2013年第11期56卷 2122-2127页

作者： liu yimin Department of Physics Shaoguan University

We propose a potentially practical scheme to generate macroscopic W-type state of N atomic ensembles in cavity QED system consisting of N atomic ensembles trapped in N single-mode cavities connected by(N 1)optical *** show that the N-qubit W-type state of atomic ensembles can be realized with high success probabilities if the coulping strength of the cavity-fiber is much stronger than that of *** also show that both the growth of atomic number in each ensemble and the increase of the number of atomic ensembles can diminish the detrimental influence from dissipative *** idea provides a scalable way to an atomic-ensemble-based quantum network,which is plausible with current available technology.

关键词： entanglement atom ensemble cavity QED

中拉萨地体当惹雍措锆石微量元素特征及其对地壳厚度演化的指示

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地学前缘 2025年第1期32卷 343-366页

作者：刘晓惠刘一珉丁林郭晓玉黄兴富李蕙琳高锐中国石油大学(北京)地球物理学院油气资源与工程全国重点实验室北京102249 中国科学院地质与地球物理研究所岩石圈演化与环境演变全国重点实验室北京100029 中国科学院青藏高原研究所青藏高原地球系统与资源环境重点实验室北京100101 中山大学地球科学与工程学院广东珠海519082 南方海洋科学与工程广东省实验室(珠海) 广东珠海519082 桂林理工大学地球科学学院广西桂林541004

拉萨地体位于青藏高原南部,是全球地壳厚度最大的区域之一。然而,拉萨地体地壳增厚的时间和过程仍存在一定争议。锆石的微量元素特征受控于锆石与其他微量元素载体矿物之间的共生关系,即不同矿物的分配系数不同,因此,锆石微量元素可用... 详细信息

拉萨地体位于青藏高原南部,是全球地壳厚度最大的区域之一。然而,拉萨地体地壳增厚的时间和过程仍存在一定争议。锆石的微量元素特征受控于锆石与其他微量元素载体矿物之间的共生关系,即不同矿物的分配系数不同,因此,锆石微量元素可用于定量重建地壳厚度。本研究对来自中拉萨地体当惹雍措地区的岩浆岩和沉积岩中的锆石开展了U-Pb年代学和微量元素地球化学研究。利用锆石的Eu异常对地壳厚度进行定量重建,结果显示,中拉萨地体在侏罗纪至新近纪期间,经历了两次地壳减薄(150~130和85~65 Ma)和两次地壳增厚(130~85和65~15 Ma)事件。在150~130 Ma期间,中拉萨地体地壳减薄主要与班公湖—怒江洋的板片回撤有关。在130~85 Ma期间,由于新特提斯洋向北俯冲和班公湖—怒江洋向南俯冲,中拉萨地体发生了地壳增厚。在85~65 Ma期间,新特提斯洋的板片回撤和弧后拉张导致中拉萨地体再次发生地壳减薄。在65~15 Ma,印度与亚欧板块的碰撞和后续挤压作用,导致中拉萨地体地壳再次加厚。

关键词：青藏高原中拉萨地体地壳厚度锆石U-Pb年龄锆石微量元素

Virtual-photon-induced entanglement with two nitrogen-vacancy centers coupled to a high-Q silica microsphere cavity

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Science China(Physics,Mechanics & Astronomy) 2013年第11期56卷 2138-2142页

作者： liu yimin Department of Physics Shaoguan University

We propose a potentially practical scheme for efcient generation of entanglement with two nitrogen-vacancy centers(NVC)coupled to a whispering-gallery mode *** virtue of the virtual-photon-excitation,the entanglement with two separate NVC can be produced in a deterministic *** required operations are very close to the capabilities of current experimental *** efects of decoherence induced by the cavity decay and the atomic spontaneous decay are also investigated.

关键词： entanglement nitrogen-vacancy center cavity QED

Vertical Structures of Convective and Stratiform Clouds in Boreal Summer over the Tibetan Plateau and Its Neighboring Regions

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Advances in Atmospheric Sciences 2019年第10期36卷 1089-1102,I0001,I0002页

作者： Yafei YAN yimin liu State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Shanghai Meteorological Bureau Shanghai 200030 China University of Chinese Academy of Sciences Beijing 100049 China

Cloud is essential in the atmosphere, condensing water vapor and generating strong convective or large-scale persistent precipitation. In this work, the relationships between cloud vertical macro- or microphysical properties, radiative heating rate, and precipitation for convective and stratiform clouds in boreal summer over the Tibetan Plateau (TP) are analyzed and compared with its neighboring land and tropical oceans based on CloudSat/CALIPSO satellite measurements and TRMM precipitation data. The precipitation intensity caused by convective clouds is twofold stronger than that by stratiform clouds. The vertical macrophysics of both cloud types show similar features over the TP, with the region weakening the precipitation intensity and compressing the cloud vertical expansion and variation in cloud top height, but having an uplift effect on the average cloud top height. The vertical microphysics of both cloud types under conditions of no rain over the TP are characterized by lower-level ice water, ice particles with a relatively larger range of sizes, and a relatively lower occurrence of denser ice particles. The features are similar to other regions when precipitation enhances, but convective clouds gather denser and larger ice particles than stratiform clouds over the TP. The atmospheric shortwave (longwave) heating (cooling) rate strengthens with increased precipitation for both cloud types. The longwave cooling layer is thicker when the rainfall rate is less than 100 mm d?1, but the net heating layer is typically compressed for the profiles of both cloud types over the TP. This study provides insights into the associations between clouds and precipitation, and an observational basis for improving the simulation of convective and stratiform clouds over the TP in climate models.

关键词： CloudSat/CALIPSO cloud vertical structures convective precipitation stratiform precipitation Tibetan Plateau

Epigenetic modifiers: catalytic or noncatalytic, that is the question

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Frontiers of Medicine 2024年第5期18卷 941-943页

作者： yimin liu Haitao Li State Key Laboratory of Molecular Oncology Beijing Frontier Research Center for Biological StructureSchool of Basic Medical SciencesTsinghua UniversityBeijing 100084China SXMU-Tsinghua Collaborative Innovation Center for Frontier Medicine Shanxi Medical UniversityTaiyuan 030001China Tsinghua-Peking Center for Life Sciences Beijing 100084China

Epigenetic modifiers are enzymes that catalyze covalent chemical modifications on chromatin and thus play important roles in setting relatively stable states for gene expression and cell *** has been widely observed that mutations in epigenetic modifiers cause various types of human diseases,such as developmental defects and ***,deciphering how the mutations affect functions of the epigenetic modifiers in developmental and pathological conditions is crucial for understanding the underlying mechanisms and for identifying potential therapeutic targets.

关键词： identity. modifiers catalytic

不同的扩大的血管周围间隙对急性缺血性脑卒中患者自发性出血性转化影响的差异性

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中华老年心脑血管病杂志 2025年第1期27卷 80-83页

作者：欧茹刘益民黄文纯李其岩佛山市南海区第六人民医院脑科 528000 佛山市南海区第六人民医院放射科 528000 佛山市南海区第六人民医院病案室 528000

目的探讨不同组别的扩大的血管周围间隙(enlarged perivascular space,EPVS)对急性缺血性脑卒中患者自发性出血性转化的影响的差异性。方法选取2021年1月至2024年6月南海区第六人民医院脑科收治的急性缺血性脑卒中患者595例,入院后72h... 详细信息

目的探讨不同组别的扩大的血管周围间隙(enlarged perivascular space,EPVS)对急性缺血性脑卒中患者自发性出血性转化的影响的差异性。方法选取2021年1月至2024年6月南海区第六人民医院脑科收治的急性缺血性脑卒中患者595例,入院后72h内完善MRI检查,收集入组患者的头颅MRI EPVS情况。根据头颅MRI结果分为EPVS组384例和无EPVS组211例。EPVS根据发生部位分为基底节患者135例、半卵圆中心患者132例、中脑患者117例;EPVS根据严重程度分级分为轻度患者155例、重度患者229例。在住院期间第7~10天复查头颅CT或者MRI了解颅内情况,根据第2次复查的头颅CT或MRI结果了解患者是否发生自发性出血性转化,分析并比较不同部位及不同严重程度级别EPVS患者自发性出血性转化发生率的差异。结果EPVS组出血性转化比例显著高于无EPVS组,差异有统计学意义(27.08%vs 8.53%,P<0.01)。基底节患者自发性出血性转化发生率显著高于半卵圆中心和中脑患者,差异有统计学意义(40.00%vs 21.97%vs 17.95%,P<0.01);重度患者自发性出血性转化比例显著高于轻度患者,差异有统计学意义(33.19%vs 18.06%,P<0.01)。结论不同部位及严重程度级别的EPVS对急性缺血性脑卒中患者自发性出血性转化的影响具有差异性。基底节、严重程度为重度EPVS的急性缺血性脑卒中患者发生自发性出血性转化的风险更高,能更好预测自发性出血性转化的发生。

关键词：缺血性卒中磁共振成像自发性出血性转化扩大的血管周围间隙

Heating status of the Tibetan Plateau from April to June and rainfall and atmospheric circulation anomaly over East Asia in midsummer

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Science China Earth Sciences 2005年第2期48卷 250-257页

作者： DUAN Anmin liu yimin WU Guoxiong State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing100029China

Based on the 1958-1999 monthly averaged reanalysis data of the National Center for Environmental Prediction(NCEP)/National Center for Atmospheric Research(NCAR)and the rainfall data of 160 Chinese surface stations,the relationship between rainfall and the atmospheric circulation anomaly over East Asia(EA)in July and the sensible heating(SH)over the Tibetan Plateau(TP)from April to June(AMJ)is investigated by using the rotational experimental orthogonal function(REOF)*** results show that the TP is an isolated heating source in this *** lagged correlation analysis between the first rotational principal component(RPC)of SH over the TP in May and rainfall of EA in July demonstrates that strong SH over the TP before July leads to a positive rainfall anomaly over the TP,the valley between the Yangtze River and Huaihe River,and the regions south and southeast of the TP,and the Sichuan Basin and Yunnan-Guizhou Plateau,but less rainfall anomaly over the regions north,northeast,and west of the *** rainfall anomaly patterns are shown to be well coordinated with those of the circulation and vapor flux fields,and are explained by using the thermal adaptation theory and quasi-stationary large-scale vorticity ***,the status of SH over the TP during AMJ can be used as a predictor for the rainfall anomaly over EA,especially in the valley between the Yangtze River and Huaihe River.

关键词： Tibetan Plateau sensible heating East Asia rainfall circulation.

An assessment of summer sensible heat flux on the Tibetan Plateau from eight data sets

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Science China Earth Sciences 2012年第5期55卷 779-786页

作者： ZHU XiaYing liu yimin WU GuoXiong State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics(LASG) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China National Climate Center China Meteorological AdministrationBeijing 100081China

The eight datasets of the summer (June-August) surface sensible heat (SH) flux over the Tibetan Plateau (TP) are compared on the time scales of the climatology,interannual variability and linear trend during *** data sets include five reanalyses (National Center for Environmental Prediction reanalysis,NCEPR1 and NCEPR2,NCEP climate forecast system reanalysis,CFSR,Japanese 25-year reanalysis,JRA,and European Centre for Medium Range Weather Forecasts reanalysis,ERA40),two land surface model outputs (Noah model data of Global Land Data Assimilation System version 2,G2_Noah,and Simple Biosphere version 2 output by Yang et al.,YSiB2),and estimated SH based on China Meteorological Administration (CMA) station observations,*** results suggest that the summer SH on the TP differs from one dataset to another due to different inputs and ***,the ERA40 and JRA distribute rather uniformly while the other six products show similar regional disparities,that is,larger in the west than in the east and stronger in the north and the south than in the middle of the *** mean magnitude of the SH averaged over the 76 stations above the TP varies considerably among each dataset with the difference of more than 20 W m?2 between the maximum (G2_Noah) and minimum (ObCh).Nevertheless,they are consistent in the interannual variability and mostly show a significant decreasing trend corresponding to the weakening surface wind speed,in spite of the distinct trend for the ground-air temperature difference among the different data *** two consistencies indicate the particular availability of the SH products,which is helpful to the relevant climate dynamics research.

关键词： Tibetan Plateau sensible heat flux assessment interannual variation linear trend

Photonic phase transition in circuit quantum electrodynamics lattices coupled to superconducting phase qubits

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Science China(Physics,Mechanics & Astronomy) 2014年第11期57卷 2092-2097页

作者： liu yimin JIN WuYin YOU JiaBin Department of Physics Shaoguan University School of Mechanical & Electronical Engineering Lanzhou University of Technology Center for Quantum Technologies and Physics Department National University of Singapore3 Science Drive 2117543Singapore

A hybrid quantum architecture was proposed to engineer a localization-delocalization phase transition of light in a two-dimension square lattices of superconducting coplanar waveguide resonators,which are interconnected by current-biased Josephson junction phase *** find that the competition between the on-site repulsion and the nonlocal photonic hopping leads to the Mott insulator-superfluid *** using the mean-field approach and the quantum master equation,the phase boundary between these two different phases could be obtained when the dissipative effects of superconducting resonators and phase qubit are *** good tunability of the effective on-site repulsion and photon-hopping strengths enable quantum simulation on condensed matter physics and many-body models using such a superconducting resonator lattice *** experimental feasibility is discussed using the currently available technology in the circuit QED.

关键词： hopping resonator waveguide junction engineer currently insulator enable photonic condensed

Understanding the Surface Temperature Cold Bias in CMIP5 AGCMs over the Tibetan Plateau

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Advances in Atmospheric Sciences 2017年第12期34卷 1447-1460页

作者： Xiaolei CHEN yimin liu Guoxiong WU State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of Sciences University of Chinese Academy of Sciences

The temperature biases of 28 CMIP5 AGCMs are evaluated over the Tibetan Plateau(TP) for the period 1979–2005. The results demonstrate that the majority of CMIP5 models underestimate annual and seasonal mean surface 2-m air temperatures(Tas) over the TP. In addition, the ensemble of the 28 AGCMs and half of the individual models underestimate annual mean skin temperatures(Ts) over the TP. The cold biases are larger in Tasthan in Ts, and are larger over the western TP. By decomposing the Tsbias using the surface energy budget equation, we investigate the contributions to the cold surface temperature bias on the TP from various factors, including the surface albedo-induced bias, surface cloud radiative forcing, clear-sky shortwave radiation, clear-sky downward longwave radiation, surface sensible heat flux, latent heat flux,and heat storage. The results show a suite of physically interlinked processes contributing to the cold surface temperature *** negative surface albedo-induced bias associated with excessive snow cover and the surface heat fluxes are highly anticorrelated, and the cancelling out of these two terms leads to a relatively weak contribution to the cold bias. Smaller surface turbulent fluxes lead to colder lower-tropospheric temperature and lower water vapor content, which in turn cause negative clear-sky downward longwave radiation and cold bias. The results suggest that improvements in the parameterization of the area of snow cover, as well as the boundary layer, and hence surface turbulent fluxes, may help to reduce the cold bias over the TP in the models.

关键词： surface temperature cold bias CMIP5 AMIP Tibetan Plateau surface energy budget