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Single crystalline CH_3NH_3PbI_3 self-grown on FTO/TiO_2 substrate for high efficiency perovskite solar cells

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Science Bulletin 2017年第17期62卷 1173-1176页

作者： Jinjin Zhao guoli Kong Shulin Chen Qian Li Boyuan Huang Zhenghao liu Xingyuan San Yujia Wang Chen Wang Yunce Zhen Haidan Wen Peng Gao Jiangyu Li School of Materials Science and Engineering Shijiazhuang Tiedao UniversityShijiazhuang 050043China Shenzhen Key Laboratory of Nanobiomechanics Shenzhen Institutes of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China Electron Microscopy Laboratory and International Center for Quantum MaterialsSchool of PhysicsPeking UniversityBeijing 100871China X-ray Science Division Argonne National LaboratoryLemontIL 60439USA department of Mechanical Engineering University of WashingtonSeattleWA 98195-2600USA Shenyang National Laboratory for Materials Science(SYNL) Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Collaborative Innovation Center of Quantum Matter Beijing 100871China Srate Key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin 150001China

Since its first report in 2009,CH_3NH_3PbI_3-based perovskite solar cells(PSCs)have emerged as one of the most exciting developments in the next generation photovoltaic(PV)technologies[1],with its PV conversion effici... 详细信息

关键词：太阳能电池钙钛矿型二氧化钛基电池效率单晶高生长 PSCs 光电转换效率

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含红外发散的低温玻璃超声吸收理论

物理学报 1987年第11期 1441-1450页

作者：王国樑戴培英范希庆姜王也刘福绥郑州大学物理系北京大学物理系

本文采用红外发散理论和二能级体系模型,讨论玻璃超声吸收在2K温度以下的行为,与现有的隧道二能级模型不同,我们把Bloch方程看作“磁化强度”所满足的宏观方程,方程中所有的物理量都是系综平均值。并且把缺陷态看作处在局域涨落场中的... 详细信息

本文采用红外发散理论和二能级体系模型,讨论玻璃超声吸收在2K温度以下的行为,与现有的隧道二能级模型不同,我们把Bloch方程看作“磁化强度”所满足的宏观方程,方程中所有的物理量都是系综平均值。并且把缺陷态看作处在局域涨落场中的赝自旋,提出了在低温下赝自旋角扩散与温度的关系。我们不但得到与实验符合较好的理论吸收曲线,并且解释了弱照射共振吸收正比于T-0.7和饱和吸收正比于ω2的实验规律。

关键词：红外发散二能级超声吸收实验规律偶极相互作用哈密顿量势阱弛豫吸收曲线饱和吸收

氯自由基介导的光催化芳基醚C(sp^(3))−H氧化生成酯

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Chinese Journal of Catalysis 2024年第3期58卷 123-128页

作者：刘玉庭聂贝黎李宁刘慧芳王峰中国科学技术大学化学物理系安徽合肥230026 中国科学院大连化学物理研究所辽宁大连116023 郑州大学河南先进技术研究院河南郑州450003 中国科学院大学北京100049

饱和的碳氢键氧化是合成化学和化学工业中一类重要的化学反应.然而,饱和C(sp^(3))−H键离解能(BDEs)较高、极性较弱,导致了底物难以活化和催化转化效率较低等问题.在过去的几十年,C(sp^(3))−H键的定向活化转化取得了重要的进展.其中,关于... 详细信息

饱和的碳氢键氧化是合成化学和化学工业中一类重要的化学反应.然而,饱和C(sp^(3))−H键离解能(BDEs)较高、极性较弱,导致了底物难以活化和催化转化效率较低等问题.在过去的几十年,C(sp^(3))−H键的定向活化转化取得了重要的进展.其中,关于C(sp^(3))−H键催化氧化的研究主要涉及一些键能低的、预活化的C−H键,包括苄基型、亚甲基型、脂肪族X−CH_(2)(X=O,N)和甲苯等,含有未活化C(sp^(3))−H键的复杂化合物的选择性氧化仍具有挑战性.例如,芳基醚C(sp^(3))−H键功能化通常采用计量的过氧化物氧化剂,或者通过单电子氧化和碱促进的去质子化进一步构建C−C/C−N键,产物选择性较低,也带来了一些不利的环境影响.因此,有必要开发高效、温和的芳基醚C(sp^(3))−H键选择氧化方法,并将其应用于有机合成和药物开发.近年来,光催化C(sp^(3))−H键氧化因其操作简便、氧化还原中性等优点,已发展成为一种有用且多样的催化研究工具.本文发展了一种利用氧气作为氧化剂,在可见光驱动下选择性地将芳基醚C(sp^(3))−H键氧化成为甲酸苯酯类产物的新方法.使用Mes-10-phenyl-Acr^(+)−BF_(4)^(-)光催化剂,高效活化多种氯源(如盐酸、无机氯盐和有机氯化物)得到氯自由基,由于其具有较高的氧化能力(+2.03 V ***)和对氢原子的亲和力,能够通过氢原子转移过程活化芳基醚C(sp^(3))−键,攫取氢自由基得到相应的烷基碳自由基(•CH_(2)OPh)中间体,进一步被分子氧选择氧化得到酯类目标产物.研究结果表明,多种链状芳基醚和不同取代(如给电子基和吸电子基)芳基醚均可发生氧化反应,高收率地合成了一系列官能团丰富的甲酸苯酯类化合物.本文方法具有反应条件温和、操作简单、官能团耐受性好以及可规模化放大等优点,并且少量的水对反应没有明显影响.机理实验研究结果表明,芳基醚C(sp^(3))−H键的断裂是反应过程的决速步骤.紫外可见吸收光谱结果表明,氯离子与催化剂之间的相互作用强于底物,并且自由基捕获实验证实反应体系中存在氯自由基和烷基碳自由基物种,表明反应经历自由基路径.此外,电子顺磁共振测试结果表明,反应过程中存在单线态氧物种,可能是激发态的光催化剂直接与氧气发生能量转移得到;同位素实验(18O)揭示了甲酸苯酯类化合物氧的来源.综上,本文实现了温和条件下光催化芳基醚C(sp^(3))−H键选择氧化反应,高收率合成了一系列甲酸苯酯类化合物.该方法避免了化学计量的过氧化物和碱等添加剂的使用以及底物的过度氧化,阐明了催化反应机制,为其他醚类化合物的C(sp^(3))−H键氧化功能化提供了新思路,为后续化学合成和药物开发提供了参考和启示.

关键词：氯自由基光催化 C(sp^(3))−H键催化氧化芳基醚

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天然Nb的快中子辐射俘获截面

四川大学学报（自然科学版） 1992年第2期29卷 238-241页

作者：牟远山徐海珊向正瑜李业祥王世明刘建峰四川大学原子核科学技术研究所郑州大学物理系

用大液体闪烁探测器和飞行时间法,相对于^(197)Au测量了0.7—1.4MeV能区天然Nb的中子辐射俘获截面.在0.5—2.0MeV能区,对^(93)Nb的辐射俘获截面进行了理论计算.

关键词：俘获截面中子铌

Engineering the spectra of photon triplets generated from micro/nanofiber

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Chinese physics B 2024年第3期33卷 408-414页

作者：瞿川郭东琴李笑笑刘振旗赵义张胜海卫正统 The College of Basic department Information Engineering UniversityZhengzhou 450000China

Quantum light sources are the core resources for photonics-based quantum information *** investigate the spectral engineering of photon triplets generated by third-order spontaneous parametric down-conversion in micro/*** phase mismatching at one-third pump frequency gives rise to non-degenerate photon triplets,the joint spectral intensity of which has an elliptical locus with a fixed eccentricity of√6/***,we propose a frequency-division scheme to separate non-degenerate photon triplets into three channels with high heralding efficiency for the first *** an appropriate pump wavelength can compensate for the fabrication errors of micro/nanofiber and also generate narrowband,non-degenerate photon triplet sources with a high signal-to-noise ***,the long-period micro/nanofiber grating introduces a new controllable degree of freedom to tailor phase matching,resulting from the periodic oscillation of *** this scheme,the wavelength of photon triplets can be flexibly tuned using quasi-phase *** study the generation of photon triplets from this novel perspective of spectrum engineering,and we believe that this work will accelerate the practical implementation of photon triplets in quantum information processing.

关键词： photon triplets micro/nanofiber spectrum engineering

Blocking the PD-1 signal transduction by occupying the phosphorylated ITSM recognition site of SHP-2

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Science china Life Sciences 2024年

作者： Wenjie Li Wenyi Mei Hewei Jiang Jie Wang Xiaoli Li Lina Quan Yanyan Diao Yanni Ma Sisi Fan Zhuwei Xie Mengdie Gong Huan Zhu Dewen Bi Feng Zhang Lei Ma Jian Zhang Yufeng Gao Aris Paschalidis Honghuang Lin Fangfang liu Kangdong liu Mingliang Ye Zhenjiang Zhao Yajun Duan Zhuo Chen Yufang Xu Weilie Xiao Shengce Tao Lili Zhu Honglin Li Innovation Center for AI and Drug Discovery East China Normal University Shanghai Key Laboratory of New Drug Design School of PharmacyEast China University of Science&Technology Shanghai Center for Systems Biomedicine Key Laboratory of Systems Biomedicine (Ministry of Education)Shanghai Jiao Tong University Lingang Laboratory Key Laboratory of Medicinal Chemistry for Natural Resource Ministry of EducationYunnan Characteristic Plant Extraction LaboratoryYunnan Provincial Center for Research&Development of Natural ProductsState Key Laboratory for Conservation and Utilization of Bio-Resources in YunnanSchool of Pharmacy and School of Chemical Science and TechnologyYunnan University CAS Key Laboratory of Separation Sciences for Analytical Chemistry National Chromatographic R&A CenterDalian Institute of Chemical PhysicsChinese Academy of Sciences department of Cardiology The First Affiliated Hospital of USTCDivision of Life Sciences and MedicineUniversity of Science and Technology of China department of Infectious Diseases The First Affiliated Hospital of Anhui Medical University department of Medicine University of Massachusetts Chan Medical School department of Pathophysiology School of Basic Medical SciencesAcademy of Medical ScienceCollege of MedicineZhengzhou University

Targeting the PD-1/PD-L1 axis with small-molecular inhibitors is a promising approach for immunotherapy. Here, we identify a natural pentacyclic triterpenoid, Pygenic Acid A(PA), as a PD-1 signaling inhibitor. PA exerts anti-tumor activity in hPD-1 knock-in C57BL/6 mice and enhances effector functions of T cells to promote immune responses by disrupting the PD-1 signaling transduction. Furthermore, we identify SHP-2 as the direct molecular target of PA for inhibiting the PD-1 signaling transduction. Subsequently, mechanistic studies suggest that PA binds to a new druggable site in the phosphorylated PD-1 ITSM recognition site of SHP-2, inhibiting the recruitment of SHP-2 by PD-1. Taken together, our findings demonstrate that PA has a potential application in cancer immunotherapy and occupying the phosphorylated ITSM recognition site of SHP-2 may serve as an alternative strategy to develop PD-1 signaling inhibitors. In addition, our success in target recognition provides a paradigm of target identification and confirmation for natural products.

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在幺正规范(ξ→∞)下推导t→cγ振幅

郑州大学学报（理学版） 2021年第2期53卷 102-110页

作者：柳国丽别素雅郑州大学物理学院河南郑州450001

以μ→eγ为例,说明此类改变衰变过程在内线为矢量传播子时,不考虑约束条件的计算不能自动地消去单圈发散项的问题;然后从电磁场的规范不变性和Ward恒等式出发,给出以t→cγ为代表的衰变过程的洛伦兹结构;最后计算它在幺正规范下的散射... 详细信息

以μ→eγ为例,说明此类改变衰变过程在内线为矢量传播子时,不考虑约束条件的计算不能自动地消去单圈发散项的问题;然后从电磁场的规范不变性和Ward恒等式出发,给出以t→cγ为代表的衰变过程的洛伦兹结构;最后计算它在幺正规范下的散射振幅。计算的重点部分是选择t→cγ过程而不是继续沿用μ→eγ衰变过程。

关键词：味道改变衰变幺正规范费曼积分

High-current MoS transistors with non-planar gate configuration

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Science Bulletin 2021年第8期66卷 777-782,M0003页

作者： Jun Lin Bin Wang Zhenyu Yang guoli Li Xuming Zou Yang Chai Xingqiang liu Lei Liao Key Laboratory for Micro/Nano Optoelectronic Devices of Ministry of Education&Hunan Provincial Key Laboratory of Low-Dimensional Structural physics and Devices School of Physics and ElectronicsHunan UniversityChangsha 410082China department of Applied physics The Hong Kong Polytechnic UniversityHong KongChina College of Microtechnology&Nanotechnology Qingdao UniversityQingdao 266071China State Key Laboratory for Chemo/Biosensing and Chemometrics School of Physics and ElectronicsHunan UniversityChangsha 410082China

The ever-decreasing size of transistors requires effectively electrostatic control over ultra-thin semiconductor *** design of the gate configuration can fully persevere the intrinsic property of two-dimensional(2 D)*** we design and demonstrate a 2 D Mo S_(2) transistor with omega-shaped gate,in which the local gate coupling is enhanced by the non-planar *** omega-shaped non-planar transistors exhibit a high current of 0.89 A/lm and transconductance of32.7 l S/*** high performance and desirable current saturation promise the construction of robust logic *** inverters show a voltage gain of 26.6 and an ideal total margin nearly 89%.We also assemble NOT-AND(NAND)gate on an individual Mo S_(2) flake,and the constructed NAND gate demonstrates the universal functionality of the transistors as *** work provides an alternative strategy to fully take the advantages of 2 D materials for high-performance field-effect transistors.

关键词： MoS_(2)transistors Omega-shaped gate Non-planar High current density

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FASER实验:简介与研究进展

科学通报 2024年第8期69卷 1025-1033页

作者：刘锦枫逄昊王驰艾小聪陈新胡震清华大学物理系北京100084 清华大学致理书院北京100084 郑州大学物理学院(微电子学院) 郑州450001

FASER(ForwArd Search ExpeRiment)是一个位于大型强子对撞机(Large Hadron Collider,LHC)上的前向粒子探测实验.LHC质子对撞产生的质量轻、能量高的粒子往往会沿着束流方向飞行,并逃离传统粒子探测器的覆盖区域.对这些前向粒子的探测... 详细信息

FASER(ForwArd Search ExpeRiment)是一个位于大型强子对撞机(Large Hadron Collider,LHC)上的前向粒子探测实验.LHC质子对撞产生的质量轻、能量高的粒子往往会沿着束流方向飞行,并逃离传统粒子探测器的覆盖区域.对这些前向粒子的探测和研究是传统探测器实验很好的补充.FASER探测器(包括其专门用于探测中微子的子探测器FASERν)位于ATLAS对撞点处束流切线方向下游480 m,物理目标包括可能的暗物质候选者和对撞机产生的中微子.2023年3月,FASER首次直接探测到约153个对撞机产生的高能中微子,信号显著度为16σ.随后,FASER合作组又公布了其暗光子搜寻结果,未发现显著信号,但给出了质量在17~70 MeV范围内、■在2×10^(–5)~1×10^(–4)范围内的暗光子可能性的世界最好限制.正在计划中的前向物理设施(Forward Physical Facility,FPF)或将成为未来HL-LHC时代前向物理研究的新阵地.本文将介绍FASER实验装置及其物理目标,并简要介绍FASER初步的实验结果.

关键词： FASER FASERν FPF 前向物理中微子暗光子