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B→xsγ, xsl+l~-Decays and Constraints on Mass Insertion Parameters in MSSM

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Communications in Theoretical Physics 2006年第10期46卷 687-696页

作者： XIAO Zhen-Jun,~+ li Feng-Ying, and ZOU Wen-Jun Department of Physics and Institute of Theoretical Physics, Nanjing Normal University, Nanjing 210097, China Department of Physics and Institute of Theoretical Physics Nanjing Normal University Nanjing 210097 China

In this paper, we study the upper bounds on the mass insertion parameters (δ~q)in the minimal supersymmetric standard model. We found that the information from the measured branching ratio of B→Xl+l~-decaycan help us to improve the upper bounds on the mass insertions parameters(δ. Some regions allowed by thedata of Br(B→Xγ)are excluded by the requirement of an SM-like C(m)imposed by the data of Br(B→Xl+l~-).

关键词： B meson decay the minimal supersymmetric standard model mass insertion

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提高布里渊光时域反射系统传感性能的方法

光学学报 2015年第1期35卷 61-70页

作者：李永倩李晓娟安琪华北电力大学电子与通信工程系河北保定071003

根据谱整形的思想将脉冲预抽运的概念引入布里渊光时域反射系统,提出了一种提高传感性能的方法。该方法利用由预抽运脉冲和传感脉冲组成的阶梯脉冲作调制信号,通过预抽运脉冲和传感脉冲的受激布里渊作用实现布里渊谱的整形和传感信号的... 详细信息

根据谱整形的思想将脉冲预抽运的概念引入布里渊光时域反射系统,提出了一种提高传感性能的方法。该方法利用由预抽运脉冲和传感脉冲组成的阶梯脉冲作调制信号,通过预抽运脉冲和传感脉冲的受激布里渊作用实现布里渊谱的整形和传感信号的放大,可有效地解决系统空间分辨率和测量精度的矛盾,并可提高系统信噪比,增加传感距离。通过受激布里渊稳态方程的瞬态分析对阶梯脉冲调制布里渊光时域反射系统中的受激布里渊散射模型进行了求解,对阶梯脉冲进行了最佳化设计,比较了矩形脉冲、洛伦兹形脉冲和阶梯脉冲调制时的系统性能。结果表明,当预抽运脉冲和传感脉冲参数为50ns、0.2W和2ns、1W时,采用阶梯脉冲时的布里渊谱宽约为44MHz,10km光纤末端信噪比较采用矩形脉冲时提高了7.97dB。最后,通过实验验证了所提方法的可行性。

关键词：光纤光学光纤传感阶梯脉冲调制声波预抽运布里渊光时域反射谱整形

High-precision potassium isotope analysis using the Nu Sapphire collision cell(CC)-MC-ICP-MS

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Science China Earth Sciences 2022年第8期65卷 1510-1521页

作者： Wenjun li Mengmeng CUI Qiqi PAN Jing WANG Bingyu GAO Shanke liU Meng YUAN Benxun SU Ye ZHAO Fang-Zhen TENG Guilin HAN Key Laboratory of Mineral Resources Institute of Geology and GeophysicsChinese Academy of SciencesBeijing100029China University of Chinese Academy of Sciences Beijing100049China State Key Laboratory of lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing100029China Nu Instruments WrexhamLL139XSUK Isotope Laboratory Department of Earth and Space SciencesUniversity of WashingtonSeattleWA98195USA Institute of Earth Sciences China University of Geosciences(Beijing)Beijing100083China

This study presents high-precision analyses of stable potassium(K)isotope ratio using the recently-developed,collision-cell multi-collector inductively coupled plasma mass spectrometry(CC-MC-ICP-MS,Nu Sapphire).The accuracy of our analyses is confirmed by measuring well-characterized geostandards(including rocks and seawater).Our results are consistent with literature values and a precision of 0.04‰(2SD)has been achieved based on multiple measurements of BCR-2 geostandard over a six-month *** also evaluate factors that may lead to artificial isotope fractionations,including the mismatches in K concentration and acid molarity between samples and bracketing standards,as well as potential *** the K adsorption capacity of AGW50-X8(200-400 mesh)is reduced with an increasing amount of matrix elements,less than 150µg K was loaded during the column *** evaluate the potential use of K isotopes as an archive of paleo seawater composition,δ^(41)K values of an international seawater standard(IAPSO),a Mn-nodule(NOD-P-1),and two iron formation standards(FeR-2 and FeR-4)are *** δ^(41)K value of IAPSO is consistent with other seawater samples reported previously,further substantiating a homogeneous K isotopic distribution in modern global *** K isotopes in Mn-nodule(NOD-P-1:−0.121±0.013‰)and iron formation samples(FeR-2:−0.538±0.009‰;FeR-4:−0.401±0.008‰)seem to be an effective tracer of their formation genesis and compositional changes of ancient *** results suggest that high-precision measurements of stable K isotopes can be routinely obtained and open up a large variety of geological applications,such as continental weathering,hydrothermal circulation and alteration of oceanic crust.

关键词： CC-MC-ICP-MS Potassium isotopes Geostandards Sample-standard bracketing method Low energy path

Mitochondrial transplantation confers protection against the effects of ischemic stroke by repressing microglial pyroptosis and promoting neurogenesis

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Neural Regeneration Research 2024年第6期19卷 1325-1335页

作者： li Sun Zhaoyan Zhao Jing Guo Yuan Qin Qian Yu Xiaolong Shi Fei Guo Haiqin Zhang Xude Sun Changjun Gao Qian Yang Department of Experimental Surgery The Second Affiliated Hospital of Air Force Medical UniversityXi’anShaanxi ProvinceChina Department of Anesthesiology The Second Affiliated Hospital of Air Force Medical UniversityXi’anShaanxi ProvinceChina

Transferring healthy and functional mitochondria to the lateral ventricles confers neuroprotection in a rat model of ischemia-reperfusion *** mitochondrial transplantation is also beneficial in pediatric patients with cardiac ischemia-reperfusion ***,transplantation of functional exogenous mitochondria may be a promising therapeutic approach for ischemic *** explore the neuroprotective effect of mitochondria transplantation and determine the underlying mechanism in ischemic stroke,in this study we established a photo-thrombosis-induced mouse model of focal ischemia and administered freshly isolated mitochondria via the tail vein or to the injury site(in situ).Animal behavior tests,immunofluorescence staining,2,3,5-triphenyltetrazolium chloride(TTC)staining,mRNA-seq,and western blotting were used to assess mouse anxiety and memory,cortical infarct area,pyroptosis,and neurogenesis,*** bioinformatics analysis,western blotting,co-immunoprecipitation,and mass spectroscopy,we identified S100 calcium binding protein A9(S100A9)as a potential regulator of mitochondrial function and determined its possible interacting *** between exogenous and endogenous mitochondria,as well as the effect of exogenous mitochondria on recipient microglia,were assessed in *** data showed that:(1)mitochondrial transplantation markedly reduced mortality and improved emotional and cognitive function,as well as reducing infarct area,inhibiting pyroptosis,and promoting cortical neurogenesis;(2)microglial expression of S100A9 was markedly increased by ischemic injury and regulated mitochondrial function;(3)in vitro,exogenous mitochondria enhanced mitochondrial function,reduced redox stress,and regulated microglial polarization and pyroptosis by fusing with endogenous mitochondria;and(4)S100A9 promoted internalization of exogenous mitochondria by the microglia,thereby amplifying their pro-proliferation and anti-inflammatory ***

关键词： ischemic stroke microglia mitochondria transplantation neurogenesis pyroptosis

Constructing low-cost Ni3C/twin-crystal Zn0.5Cd0.5S heterojunction/homojunction nanohybrids for efficient photocatalytic H2 evolution

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Chinese Journal of Catalysis 2021年第1期42卷 25-36页

作者： Rongchen Shen Yingna Ding Shibang li Peng Zhang Quanjun Xiang Yun Hau Ng Xin li College of Forestry and Landscape Architecture Key Laboratory of Energy Plants Resource and UtilizationMinistry of AgricultureSouth China Agricultural UniversityGuangzhou 510642GuangdongChina College of Materials and Energy South China Agricultural UniversityGuangzhou 510642GuangdongChina State Center for International Cooperation on Designer Low-Carbon&Environmental Materials(CDLCEM) School of Materials Science and EngineeringZhengzhou UniversityZhengzhou 450001HenanChina State Key Laboratory of Electronic Thin Film and Integrated Devices University of Electronic Science and Technology of ChinaChengdu 610054SichuanChina School of Energy and Environment City University of Hong KongHong Kong SAR

The development of low-cost semiconductor photocatalysts for highly efficient and durable photocatalytic H2 evolution under visible light is very *** this study,we combine low-cost metallic Ni3C cocatalysts with twin nanocrystal Zn0.5Cd0.5S(ZCS)solid solution homojunctions for an efficient visible-light-driven H2 production by a simple ***-synthesized Zn0.5Cd0.5S-1%Ni3C(ZCS-1)heterojunction/homojunction nanohybrid exhibited the highest photocatalytic H2-evolution rate of 783μmol h‒1 under visible light,which is 2.88 times higher than that of pristine twin nanocrystal ZCS solid *** apparent quantum efficiencies of ZCS and ZCS-1 are measured to be 6.13%and 19.25%at 420 nm,***,the homojunctions between the zinc blende and wurtzite segments in twin nanocrystal ZCS solid solution can significantly improve the light absorption and separation of photogenerated electron-hole ***,the heterojunction between ZCS and metallic Ni3C NP cocatalysts can efficiently trap excited electrons from ZCS solid solution and enhance the H2-evolution kinetics at the surface for improving catalytic *** study demonstrates a unique one-step strategy for constructing heterojunction/homojunction hybrid nanostructures for a more efficient photocatalytic H2 evolution compared to other noble metal photocatalytic systems.

关键词： Photocatalytic H2 evolution Zn0.5Cd0.5S solid solution Twin nanocrystal Heterojunction/homojunction Earth-abundant Ni3C cocatalysts

能源互联微网系统供需双侧多能协同优化策略及其求解算法

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电网技术 2017年第2期41卷 409-417页

作者：曾鸣韩旭李冉李源非彭丽霖李娜华北电力大学经济与管理学院北京市昌平区102206 国网天津市电力公司经济技术研究院天津市河东区300000

为提高新能源利用效率,充分考虑了供给侧、需求侧以及能源转换之间的影响作用,构建了能源互联微网系统供需双侧多能协同优化策略模型,提出了求解混合整数非线性规划模型的带个体差异蚁群算法与粒子群优化算法相结合的组合算法(particle ... 详细信息

为提高新能源利用效率,充分考虑了供给侧、需求侧以及能源转换之间的影响作用,构建了能源互联微网系统供需双侧多能协同优化策略模型,提出了求解混合整数非线性规划模型的带个体差异蚁群算法与粒子群优化算法相结合的组合算法(particle swarm optimizer-individual variation ant colony optimization,PSO-IVACO)。将所提模型及求解算法应用于我国某典型园区能源互联微网系统夏季和冬季典型日的实际算例中,并与传统分布式冷热电联供系统相比较,结果表明:PSO-IVACO算法求解此类问题具有可行性,考虑供需双侧的能源互联微网系统在夏季和冬季均具有显著经济和环境效益,促进了新能源并网消纳。

关键词：能源互联微网供需双侧协同优化

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B→X_(s)γin BLMSSM

Chinese Physics C 2021年第5期45卷 39-48页

作者： Jian-Bin Chen Meng Zhang li-li Xing Tai-Fu Feng Shu-Min Zhao Ke-Sheng Sun College of Physics and Optoelectronic Engineering Taiyuan University of TechnologyTaiyuan 030024China Department of Physics Hebei UniversityBaoding 071002China Department of Physics Baoding UniversityBaoding 071000.China

Applying the effective Lagrangian method,we study the flavor changing neutral current process b→sγwithin the minimal supersymmetric extension of the Standard Model,where baryon and lepton numbers are local gauge *** on the parameters are investigated numerically with the experimental data for the branching ratioof B→X_(s)γAdditionally,we present the corrections to direct CP-violation in B→X_(s)γand time-de-pendent CP-asymmetry in B→K*γ.With appropriate assumptions on the parameters,we find the direct CP-viola-tion Acp is very small,while one-loop contributions to S K*γcan be significant.

关键词： BLMSSM electroweak radiative corrections B decay

CdSexs1-x电子学结构及光学性质的第一性原理研究

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发光学报 2020年第2期41卷 188-193页

作者：何旭武莉莉李春秀郝霞都政成都纺织高等专科学校四川成都611731 四川大学材料科学与工程学院四川成都610101 宜春学院江西宜春336000 国家超级计算深圳中心广东深圳518055

CdSe是Ⅱ-Ⅵ族中重要的半导体材料,一定条件下可与CdS形成无限固溶体CdSexs1-x(0≤x≤1)。CdSexs1-x在薄膜太阳电池及光电器件等领域具有重要的应用,对CdSexs1-x的电子学结构和光学性质进行研究有助于进一步提高其在光电器件等方面的应... 详细信息

CdSe是Ⅱ-Ⅵ族中重要的半导体材料,一定条件下可与CdS形成无限固溶体CdSexs1-x(0≤x≤1)。CdSexs1-x在薄膜太阳电池及光电器件等领域具有重要的应用,对CdSexs1-x的电子学结构和光学性质进行研究有助于进一步提高其在光电器件等方面的应用。基于第一性原理,采用平面波超软赝势方法,计算了CdSexs1-x的电子学结构及光学性质,并将计算结果与实验进行了对比。结果表明,CdSexs1-x的晶格常数随着Se组分的增加呈线性增大趋势,态密度向低能级方向移动,禁带宽度减小,光吸收边发生一定程度的蓝移。当Se含量为0.5时,CdSexs1-x的光折射、反射和能量损失最大。除了Se和S的比例为1∶1时CdSexs1-x所属晶系为三斜晶系,其他比例下均为立方晶系。理论计算结果与实验符合。

关键词： CdSexs1-x 第一性原理电子结构光学性质

Subaquatic volcanic eruptions in continental facies and their influence on high quality source rocks shown by the volcanic rocks of a faulted depression in Northeast China

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Science China Earth Sciences 2013年第12期56卷 1926-1933页

作者： SHAN XuanLong li JiYan CHEN ShuMin RAN QingChang CHEN GuiBiao liU Chao College of Earth Sciences Jilin University Exploration and Development Research Institute Daqing Oil field Co. Ltd.

This paper reports the analysis on cores and rock slices, data on seismic and logging activities, characteristics of core samples, and the paleogeographic background of the Yingcheng Formation of the Xujiaweizi faulted depression in the Songliao Basin. The results show that some of the volcanic rocks were formed during subaquatic eruptions. These subaqueous volcanic rocks are further characterized by the interbedded black mudstone and tuffite, the presence of double-layer perlite enclosing aphyric or sparsely phyric rhyolite, the presence of a bentonite layer, and the coefficient of oxidation （Fe203/FeO）. The types of rocks are volcanic breccia, lava breccias, perlite, rhyolite, tuff and sedimentary tuff. The subaquatic eruptions are distributed mainly in Wangjiatun, Shengping, Xuxi, Xuzhong, and Xudong. The xs-I area is the most typical. The organic abundance of over- burden mud rocks within the volcanic rocks of the Yingcheng Formation indicates that these rocks represent high-quality source rocks. The analysis also shows that continental subaquatic volcanic eruptions provide a rich supply of minerals and en- ergies for the lake basin and increase the organic matter content in the water. Moreover, the water differentiation provides a good reducing environment for the conservation of organic matter, and is beneficial for the formation of high-quality source rocks. Finally, we propose a hypothesis to describe the mode of subaquatic eruptions and the formation of high-quality source rocks.

关键词： subaquatic volcanic rocks in continental facies recognition marks high-quality source rocks Yingcheng Formation Xujiaweizi faulted depression

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