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过渡态理论在化学体系中的2个应用实例

化学教育（中英文） 2021年第2期42卷 90-93页

作者：边红涛陕西师范大学化学化工学院陕西西安710119

在大学本科一二年级的物理化学教学中,化学动力学章节的学习涉及到对不同时间尺度的认识。本文利用过渡态理论得到的速率常数表达公式,以乙烷分子碳/碳单键旋转和水分子氢键交换的动力学过程为例,对这2个应用实例的动力学过程所发生的... 详细信息

在大学本科一二年级的物理化学教学中,化学动力学章节的学习涉及到对不同时间尺度的认识。本文利用过渡态理论得到的速率常数表达公式,以乙烷分子碳/碳单键旋转和水分子氢键交换的动力学过程为例,对这2个应用实例的动力学过程所发生的时间尺度做出估算。这些时间尺度的估算对于学生理解不同动力学过程的物理图像至关重要,同时也有助于加强学生对重要公式的理解并能够将这些公式在化学体系中灵活运用。

关键词：化学动力学过渡态理论碳/碳单键旋转时间尺度估算

基于超快多维振动光谱技术解析分子体系的三维空间构型

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物理化学学报 2017年第1期33卷 40-62页

作者：陈海龙边红涛郑俊荣中国科学院物理研究所北京凝聚态物理国家实验室中科院软物质物理重点实验室北京100190 陕西师范大学化学化工学院西安710119 北京大学化学与分子工程学院北京分子科学国家实验室北京100871

超快多维振动光谱技术目前已经被广泛应用到各种凝聚态分子体系中分子的结构以及快速变化动力学过程的测量之中,并有望成为新一代解析分子体系微观结构及超快行为的常规手段。本文从两个主线出发,介绍如何利用超快多维振动光谱技术解析... 详细信息

超快多维振动光谱技术目前已经被广泛应用到各种凝聚态分子体系中分子的结构以及快速变化动力学过程的测量之中,并有望成为新一代解析分子体系微观结构及超快行为的常规手段。本文从两个主线出发,介绍如何利用超快多维振动光谱技术解析分子体系的三维空间构型。一方面通过测量分子内各个振动模式跃迁偶极矩间的夹角来获得分子体系内不同基团的相对空间取向,并最终确定分子的空间构型。另一方面,通过详细解析分子间振动能量转移的机理,进而将实验中测得的振动能量转移速率转化为分子之间的距离信息。

关键词：多维振动光谱仪超快光谱二维红外光谱分子构象振动能量传递

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钙钛矿薄膜钝化策略的研究进展

物理学进展 2022年第1期42卷 1-16页

作者：赵敏张伟婷边红涛应用表面与胶体化学教育部重点实验室化学化工学院陕西师范大学西安710119

钙钛矿太阳能电池由于其优异的光电转化效率及成本低等优点被引入作为一种新的光伏器件。在过去的十几年内,钙钛矿太阳能电池的研究及发展尤为迅速,性能有了显著提高。然而,要使其进入光伏市场,研究者还需要做出巨大努力。这主要是由于... 详细信息

钙钛矿太阳能电池由于其优异的光电转化效率及成本低等优点被引入作为一种新的光伏器件。在过去的十几年内,钙钛矿太阳能电池的研究及发展尤为迅速,性能有了显著提高。然而,要使其进入光伏市场,研究者还需要做出巨大努力。这主要是由于钙钛矿薄膜自身制备的局限性,使其缺陷的存在是不可避免的,这严重影响了钙钛矿太阳能电池中载流子的数目及迁移率,从而制约了钙钛矿太阳能电池效率及稳定性的提升。本综述在对钙钛矿及其缺陷分类简单介绍的基础上,总结了近些年来钙钛矿薄膜钝化的不同策略,希望可以对钙钛矿材料领域的研究人员在选择合适钝化剂方面提供一定的参考。

关键词：钙钛矿薄膜缺陷钝化

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Cobalamin-dependent radical S-adenosyl-L-methionine protein functions with a partner to successively methylate tricyclic indole alkaloid for chuangxinmycin maturation and derivatization

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Science China Chemistry 2025年第1期 308-316页

作者： Sili Wang Jiancheng Huang Yanan Du Wei Huang Yufeng Xue Xiaokun Xu Guannan Zhong Yuanyuan Shi Bin hong Xiaoying bian Wen Liu State Key Laboratory of Chemical Biology Shanghai Institute of Organic Chemistry University of Chinese Academy of SciencesChinese Academy of Sciences State Key Laboratory of Microbial Technology Shandong University National Health Commission (NHC) Key Laboratory of Biotechnology for Microbial Drugs Institute of Medicinal BiotechnologyChinese Academy of Medical Science & Peking Union Medical College

Cobalamin(Cbl)-dependent radical S-adenosyl-L-methionine(SAM) proteins constitute the largest collection of the radical SAM superfamily that has hundreds of thousands of individual members. Many of these proteins are involved in the biosynthesis of pharmaceutically important natural products to catalyze chemically demanding reactions. In the biosynthetic pathway of chuangxinmycin(CXM), a unique indole alkaloid antibiotic with potent anti-infective activity, functionalization of the characteristic thiopyrano[4,3,2-cd]indole scaffold by regio-and stereoselective C3-methylation is believed to rely on a Cbl-dependent radical process, which, however, remained to be reconstituted biochemically. We here report the dissection of this enzymatic process, which requires the incorporation of Cxm8, a Cbl-dependent radical SAM protein, with Cxm9, a DUF5825family protein that shares no homology to any proteins of known functions. Cxm8 and Cxm9 function together by forming an unexpected heterodimeric complex that selectively catalyzes C3-methylation of the tricyclic indole-S-hetero ring system in a successive manner, achieving CXM and a recently identified, C3-dimethylated congener. Detailed biochemical characterization,isotope labeling, structural simulation and bioinformatics analysis rationalized the catalysis of the Cxm8/Cxm9 complex and particularly the necessity of the DUF5825 protein for C3-methylase activity. This is the first example that a Cbl-dependent protein acts with a partner to exhibit radical SAM activity.

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ImSpiRE: image feature-aided spatial resolution enhancement method

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Science China Life Sciences 2025年第1期 272-283页

作者： Yuwei Hua Yizhi Zhang Zhenming Guo Shan bian Yong Zhang State Key Laboratory of Cardiovascular Diseases and Medical Innovation Center Institute for Regenerative MedicineDepartment of NeurosurgeryShanghai East HospitalShanghai Key Laboratory of Signaling and Disease ResearchFrontier Science Center for Stem Cell ResearchSchool of Life Sciences and TechnologyTongji University

The resolution of most spatially resolved transcriptomic technologies usually cannot attain the single-cell level, limiting their applications in biological discoveries. Here, we introduce ImSpiRE, an image feature-aided spatial resolution enhancement method for in situ capturing spatial transcriptome. Taking the information stored in histological images, ImSpiRE solves an optimal transport problem to redistribute the expression profiles of spots to construct new transcriptional profiles with enhanced resolution, together with extending the gene expression profiles into unmeasured regions. Applications to multiple datasets confirm that ImSpiRE can enhance spatial resolution to the subspot level while contributing to the discovery of tissue domains, signaling communication patterns, and spatiotemporal characterization.

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Desulfurization Characteristics of CaO-SiO_2-BaO-CaF_2-Al_2O_3-MgO Refining Slag

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Journal of Iron and Steel Research International 2005年第5期12卷 1-2,20页

作者： GAO Yan-hong bian Ling-tao Chongqing University of Science and Technology Chongqing 400005 China Lingyuan Iron and Steel Group Co Lingyuan 122504 China

The desulfurization characteristics of CaO-SiO2-BaO-CaF2-Al2O3-MgO refining slag were studied in laboratory with the methodology of orthogonal design. The influence of basicity, Al2O3, MgO, BaO and CaF2 contents in sl... 详细信息

关键词： refining slag desulfurization orthogonal design

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环形弹子球动力学性质研究

山东科学 2009年第6期22卷 9-12页

作者：裴云昌卞洪涛张延惠林圣路山东师范大学物理与电子科学学院山东济南250014

弹子球作为一个理想模型可以用来描述受限边界腔中微观粒子运动的动力学特征。本文研究了介观二维偏心环形弹子球体系的动力学性质,利用相空间中的庞加莱截面分析了弹子球运动的特性,其结果可以为研究量子混沌和微腔输运提供理论指导。

关键词：环形弹子球经典轨道庞加莱截面

Reinforcement Learning for Linear Continuous-time Systems: an Incremental Learning Approach

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IEEE/CAA Journal of Automatica Sinica 2019年第2期6卷 433-440页

作者： tao bian Zhong-Ping Jiang Bank of America Merrill Lynch IEEE the Control and Networks Lab Department of Electrical and Computer Engineering Tandon School of Engineering New York University

In this paper, we introduce a novel reinforcement learning(RL) scheme for linear continuous-time dynamical systems. Different from traditional batch learning algorithms,an incremental learning approach is developed, which provides a more efficient way to tackle the on-line learning problem in realworld applications. We provide concrete convergence and robust analysis on this incremental-learning algorithm. An extension to solving robust optimal control problems is also given. Two simulation examples are also given to illustrate the effectiveness of our theoretical result.

关键词： Adaptive optimal control robust dynamic programming value iteration(Ⅵ)

A medical robot for needle placement therapy in liver cancer

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第4期11卷 263-269页

作者： Xing-guang DUAN Gui-bin bian hong-hua ZHAO Xing-tao WANG Qiang HUANG Intelligent Robotics Institute Beijing Institute of Technology Beijing 100081 China

Hepatocellular carcinoma (HCC) is the second most common malignancy in *** microwave ablation (MWA) is an effective method for liver cancer,a robotic surgical system with ultrasound-directed was designed to assist surgeons on positioning the *** robotic system includes a surgical robot with 5 degrees of freedom,a workstation for path-planning and image processing,a conventional 2D ultrasound device,and an electromagnetic (EM) tracking *** space,clinical operation requirements and optimal mechanical structure are the key factors to be considered in designing a medical robot suitable for use by *** on the mechanics of the needle placement robot,we have conducted detailed kinematic analysis,including a combined numerical algorithm and coordinate ***,the feasibility of the needle placement robot has been validated by experiment.

关键词： Surgical robot Needle insertion Inverse kinematics Numerical solution