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The Scalar Photon Light-Cone Distribution Amplitude in the Instanton Vacuum Model of QCD

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Chinese Physics Letters 2014年第4期31卷 22-25页

作者： MO xin liu Jue-ping Department of PhysiCs School of Physics Science and Technology Wuhan University Wuhan 430072

Based on the principle of the Lorentz covariance, the transition matrix elements from an off-shell photon state to the vacuum are parameterized by the light-cone photon distribution amplitudes （DAs）. Both the scalar off-shell photon light-cone DA and the corresponding coupling are calculated in the instanton vacuum model of quantum chromodynamics （QCD）, and their explicit analytical expressions and the numerical results are given. The results for the other chiral-odd light-cone photon DAs and their couplings are presented as well.

关键词： QCD The Scalar Photon principle

430℃下2.98dpa中子辐照后CLAM钢的拉伸和冲击性能

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核科学与工程 2016年第4期36卷 487-491页

作者：信敬平刘少军李春京徐刚黄群英吴宜灿中国科学院核能安全技术研究所中子输运理论与辐射安全重点实验室安徽合肥230031

利用高通量工程试验堆HFETR开展了CLAM钢430℃下2.98dpa的中子辐照实验,通过辐照前后拉伸和冲击性能测试与对比分析,研究了CLAM钢的中子辐照硬化和脆化效应。结果显示,CLAM钢辐照后室温测试的抗拉强度和屈服强度分别为710 MPa和615 MPa... 详细信息

利用高通量工程试验堆HFETR开展了CLAM钢430℃下2.98dpa的中子辐照实验,通过辐照前后拉伸和冲击性能测试与对比分析,研究了CLAM钢的中子辐照硬化和脆化效应。结果显示,CLAM钢辐照后室温测试的抗拉强度和屈服强度分别为710 MPa和615 MPa,较辐照前分别下降16 MPa和-0.5MPa,总延伸率减小1%,断面收缩率下降4%,保持良好的强度、塑性和韧性。冲击测试表明,CLAM钢辐照前后韧脆转变温度基本相同,上平台能量无明显变化,约为217J,未出现明显辐照脆化。CLAM钢的抗辐照性能略优于其他低活化铁素体/马氏体RAFM钢在类似辐照条件下的性能。

关键词： CLAM钢中子辐照拉伸冲击

Metastable seed-crystals: epitaxial growth of branched-array organic heterostructure nanowires

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Science China Chemistry 2025年

作者： Jin Feng Zhen-Yu Geng Ting-Yao Song Ying-xin Ma Chuan-Zeng Wang Wei Zhang Hong-Tao Lin Jin Zhou Shu-ping Zhuo Shu-Hai Chen Xue-Dong Wang School of Chemistry and Chemical Engineering Shandong University of Technology Institute of Functional Nano & Soft Materials (FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials & DevicesSoochow University College of Chemistry and Chemical Engineering Hunan Normal University

Tunable light–matter interactions are exhibited by organic low-dimensional crystals, making these crystals a promising platform for organic photonics. However, the precise synthesis of organic low-dimensional crystals remains challenging due to the stochastic nature of molecular nucleation processes. Herein, the directed nucleation process is driven by the introduction of metastable seed-crystals as the trunk, which ultimately leads to branched-array organic heterostructures. The successful formation of organic heterostructures with high-density branched arrays is attributed to the highest attachment energy (Eatt（023）=-104.25 kcal mol-1) of the exposed （023） crystal plane during the seed-crystal growth route. Significantly, these as-prepared heterostructures inherently have an ultralow lattice mismatch ratio η of 0.7%between trunk and branch, which contributes to the multi-channel photon transportation. Therefore, this work provides valuable insights into a versatile synthetic strategy for accessing low-dimensional heterostructures for integrated optoelectronics.

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Modular assembly of complex C-alkyl glycoside enabled via cooperative NHC and photoredox catalysis

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Science China Chemistry 2025年

作者： Rui-Qiang Jiao Ming Li Xi Chen Mei-Ze Xu Tian Ding Xiao-ping Gong Zhuo-Mei Li Xue-Yuan liu Yong-Min Liang State Key Laboratory of Applied Organic Chemistry Lanzhou University College of Chemistry and Chemical Engineering Northwest Normal University

C-Alkyl glycosides are found in natural products and are indispensable in drug development programs,owing to their diverse range of medicinal ***-component reactions involving glycosyl radical addition are well documented and proved efficient for the C-alkyl glycosides ***,multicomponent reactions for the rapid and controllable construction of structurally diversified C-alkyl glycosides in a single step remains a significant challenge due to the issues associated with balancing reactivity,compatibility,and ***,we report an NHC and photoredox co-catalyzed three-component method to access complex and valuable C-alkyl *** protocol exhibits broad substrate scope and excellent chemoand ***,nine types of sugars are compatible with this *** addition,the generality of this catalytic strategy was further highlighted by the potential for scalable production,the feasibility of further modifications of the products and its successful application in the late-stage functionalization of pharmaceutical skeletons.

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预取技术研究进展

计算机科学 2003年第8期30卷 28-30,55页

作者：曹新平刘美华韩真古志民张建鑫北京理工大学计算机科学工程系北京100081 中国农业银行海淀支行北京100081

World Wide Web(WWW) services have grown to levels where significant delays are expected to *** like prefetching are likely to help users to personalize their needs ,reducing their waiting times. This paperfirstly describes the architecture of prefetching,then classifies them into three types: based on branch model,based ontree model and others and presents profoundly the basic ideas of some existing prefetching algorithms. Next,severalmodels for controlling the prefetching are introduced. At last ,the trend and course concerning the prefetching algo-rithms are concluded.

关键词：网络负载网络带宽网络缓存预取技术 WWW 计算机网络网络资源

Peficitinib suppresses diffuse-type tenosynovial giant cell tumor by targeting TYK2 and JAK/STAT signaling

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Science China Life Sciences 2025年

作者： Shan Lu Chenxi Cao Wenjia Zhang Jiayi Li Jingli Yang Zisheng Huang Zhijun Wu Baitao liu Hongjie Huang Haijun Wang Yongjian Wang Dingge liu Zhihua Zhang Kaiping liu Gang Yang Xi Gong Hui Dai Yingjia Li Erdan Dong xin Zhang Yan Zhang Haihe Laboratory of Cell Ecosystem Institute of Cardiovascular Diseases The First Affiliated Hospital of Dalian Medical University Institute of Cardiovascular Sciences School of Basic Medical Sciences Peking University Health Science Center Department of Cardiology and Institute of Vascular Medicine Peking University Third HospitalState Key Laboratory of Vascular Homeostasis and Remodeling Peking University Department of Sports Medicine Peking University Third Hospital Institute of Sports Medicine of Peking University Beijing Key Laboratory of Sports Injuries Engineering Research Center of Sports Trauma Treatment Technology and Devices Ministry of Education State Key Laboratory of Membrane Biology Institute of Molecular Medicine College of Future Technology Peking University Peking University Health Science Centre Peking University Department of Immunology School of Basic Medical Sciences NHC Key Laboratory of Medical Immunology Peking University Research Center for Cardiopulmonary Rehabilitation University of Health and Rehabilitation Sciences Qingdao Hospital (Qingdao Municipal Hospital) School of Health and Life Sciences University of Health and Rehabilitation Sciences Research Unit of Medical Science Research Management/Basic and Clinical Research of Metabolic Cardiovascular Diseases Chinese Academy of Medical Sciences

Diffuse-type tenosynovial giant cell tumor(dTGCT) is a destructive but rare benign proliferative synovial neoplasm. Although surgery is currently the main treatment modality for dTGCT, the recurrence risk is up to 50%. Therefore, there is a great need for effective drugs against dTGCT with minor side effects. The Janus kinase(JAK)/signal transducer and activator of transcription(STAT) signaling plays a central role in rheumatoid arthritis(RA), a disease with similar characteristics as dTGCT, but its function in dTGCT remains *** fibroblast-like synoviocytes(FLS) and macrophages were isolated from 10 synovial tissue samples from dTGCT patients for the screening and validation of the five clinically approved JAK inhibitors to treat RA against dTGCT. Cell viability, cell death, inflammation and the activity of the JAK family members of cultured dTGCT FLS(both 2-D and 3-D) and macrophages were investigated for the efficacy of the JAK inhibitors. Here, we found that similar to RA, JAK/STAT signaling was markedly activated in the dTGCT synovium. Of the 5 JAK inhibitors, peficitinib was shown to have the most potency in addressing some of the pathological responses of dTGCT FLS and *** potency of peficitinib was much higher than pexidartinib, which is the only FDA-approved drug for dTGCT. Mechanistically, peficitinib inhibited tyrosine kinase 2(TYK2), a JAK family member necessary for the pathological progression of dTGCT FLS and macrophages. In summary, we not only revealed JAK/STAT(especially TYK2) signaling as the major mechanism underlying dTGCT, but also identified peficitinib as a promising drug against dTGCT.

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颞下颌关节紊乱病的三维CT测量

苏州大学学报（医学版） 2005年第5期25卷 829-830,833页

作者：杨建新龚建平刘瑾顾松筠苏州大学附属第二医院口腔科江苏苏州215004 苏州大学附属第二医院影像科江苏苏州215004

目的探讨三维CT测量颞下颌关节骨性结构对颞下颌关节紊乱病的意义。方法对30例颞下颌关节紊乱病患者双侧颞下颌关节进行螺旋CT扫描,三维重建,测量了关节前后间隙、下颌Spee氏曲线曲度以及张口位时髁状突的移动范围和旋转角度。另外以30... 详细信息

目的探讨三维CT测量颞下颌关节骨性结构对颞下颌关节紊乱病的意义。方法对30例颞下颌关节紊乱病患者双侧颞下颌关节进行螺旋CT扫描,三维重建,测量了关节前后间隙、下颌Spee氏曲线曲度以及张口位时髁状突的移动范围和旋转角度。另外以30名正常志愿者作为对照组,进行对比观察。结果颞下颌关节紊乱病患者矢状位的颞下颌关节前后间隙有显著性差异(P<0.01),髁状突移动距离和转动角度均比正常人小(P<0.01),Spee曲线的曲率半径大于正常人(P<0.01)。结论三维CT测量颞下颌关节骨性结构对颞下颌关节紊乱病的诊断有着积极的意义。

关键词：颞下颌关节螺旋CT 测量颞下颌关节紊乱病三维CT测量 Spee曲线螺旋CT扫描骨性结构显著性差异三维重建

Facile synthesis of the dodecahydridododecaborate (B12H122-) from borane Lewis base adducts

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Science China Chemistry 2025年

作者： Yi Jing xin-Ran liu xing-Hua Wang Hui Han Sha-Sha Liang Xi-Meng Chen Dong-Hui Wei Lai-Sheng Wang Xue-Nian Chen College of Chemistry Zhengzhou University School of Chemistry and Chemical Engineering Henan Key Laboratory of Boron Chemistry and Advanced MaterialsHenan Normal University Department of Chemistry Brown University

Polyhedral boranes are a class of well-known boron molecular clusters widely used in energy,chemistry,medicine,and materials science because of their unique physical and chemical *** efforts have been made in the past decades to find more effective synthetic methods for this important class of boron ***,existing synthetic methods suffer from low efficiency and low ***,we report a facile one-pot synthesis of[（CH3）3S]2B12H12with moderate yields at mild *** mechanisms for the multi-step chemoselective synthesis of B12H122-without other by-products are elucidated based on theoretical results and our previous *** Lewis base used in B–H bond condensation reaction,which acts as a hydrogen or to balance the newly generated polyhedral borane charges,is proposed and studied in *** current study has led to a more effective and selective synthetic method for B12H122-and has also implicated the syntheses of other new polyhedral boranes.

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二氢杨梅素分子结构与性质的密度泛函理论研究

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原子与分子物理学报 2025年第1期42卷 29-34页

作者：辛国鹏毛敏刘信平马文涛马杰张煜湖北民族大学化学与环境工程学院恩施445000

本文基于密度泛函理论(DFT),采用B3LYP泛函结合6-31G基组上对二氢杨梅素的分子几何结构进行了优化,在此基础上以水为溶剂计算二氢杨梅素分子的活性位点以及红外光谱进行分析.静电势结果表明二氢杨梅素的亲核活性位点位于酚羟基氢原子(H... 详细信息

本文基于密度泛函理论(DFT),采用B3LYP泛函结合6-31G基组上对二氢杨梅素的分子几何结构进行了优化,在此基础上以水为溶剂计算二氢杨梅素分子的活性位点以及红外光谱进行分析.静电势结果表明二氢杨梅素的亲核活性位点位于酚羟基氢原子(H23)附近;而亲电活性位点位于氧原子(O32)及其附近.前线分子轨道研究结果表明二氢杨梅素分子的最高占据轨道(HOMO)都位于酮基氧(O32)和羟基氧(O20)附近,说明这些位点易与亲电试剂反应.而最低空轨道(LUMO)位于碳原子(C12、C13、C14)区域,表明这些区域可与亲核试剂反应.简缩福井函数(f)结果证实了位于C-O-C键中的氧原子的f-值的亲电活性较其他位点氧原子大;而位于C8碳原子的f^(+)值较大,因此该位点亲核活性较强.通过理论计算所得到的二氢杨梅素的红外光谱数据与实验所得到的红外光谱数据相差不大,这就说明理论计算结果是较为可靠的.从而为实验和理论研究二氢杨梅素结构与性质的关系提供了一定的理论参考.

关键词：二氢杨梅素密度泛函理论反应活性位点量子化学计算