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Transition-metal-catalyzed C-H functionalization for late-stage modification of peptides and proteins

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Chinese Chemical Letters 2018年第7期29卷 1001-1008页

作者： xi Lu shi-Jiang He Wan-Min Cheng Jing shi Hefei National Laboratory for Physical Sciences at the Microscale CAS Key Laboratory of Urban Pollutant ConversionAnhui Province Key Laboratory of Biomass Clean EnergyiChEMUniversity of Science and Technology of China

Late-stage modification of peptides and proteins meets the increasing demand in biochemical and pharmaceutical communities. These modification strategies could provide functionalized nonproteinogenic analogues with enhanced biological activities or improved therapeutic capabilities compared to their natural counterparts. Recent years, transition-metal-promoted functionalization of ubiquitous C-H bonds has been emerged as a powerful and tunable tool in this area, both for backbone diversifications and labeling of specific moieties. These reactions were flexible and expedient in both academic and industrial laboratories, especially considering their atom and step-economy, good functional group compatibility, accurate site selectivity. This review surveys the progress achieved in the late-stage modification of peptides and proteins utilizing transition-metal-catalyzed C-H functionalization with C-C and C-X(F, Cl, O, N, B, etc.) bonds formation.

关键词： Transition-metals C-H functionalization Chemo-and site selective Late-stage modification Peptides and proteins

A new benzophenone C-glycoside from Polygala telephioides Willd

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Chinese Chemical Letters 2010年第5期21卷 584-586页

作者： Ting Jun Ma[a], xi Cheng shi[b] Chang xi Jia[a] [a] Department of Food Science Beijing Agricultural College Beijing 102206 China [b] Research Insitute of Chemical Defense Beijing 100083 China

A new benzophenone C-glucoside,3’-C-[4-O-(5-hydroxyferuloyl)-β-D-glucopyranosyl]-2′,4′,6′-trihydroxy-3,4-dimethoxy-benzophenone, named telephenone D,was isolated from the whole plants of Polygala telephioides,and... 详细信息

关键词： Polygala telephioides Benzophenone C-glucoside Telephenone D

习近平关于新质生产力重要论述的理论体系和实践指向研究

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新疆师范大学学报（哲学社会科学版） 2025年第1期46卷 60-68页

作者：方世南苏州大学东吴智库苏州大学马克思主义学院江苏省习近平新时代中国特色社会主义思想研究中心苏州大学基地江苏苏州215006

习近平总书记关于新质生产力重要论述深刻阐明了新质生产力的基本内涵、本质特征、鲜明标志、核心要素、形成规律以及实现路径等重大理论和实践问题,是具有重大原创性、标识性、系统性、实践性的理论创新成果,是习近平新时代中国特色社... 详细信息

习近平总书记关于新质生产力重要论述深刻阐明了新质生产力的基本内涵、本质特征、鲜明标志、核心要素、形成规律以及实现路径等重大理论和实践问题,是具有重大原创性、标识性、系统性、实践性的理论创新成果,是习近平新时代中国特色社会主义思想的重要组成部分。习近平总书记关于新质生产力重要论述是在推进中国式现代化进程中形成的新的生产力理论,是指导我国经济社会高质量发展的学理化、体系化的理论体系,是具有深邃而丰富辩证法则的实践指向。

关键词：中国式现代化新质生产力重要论述理论体系实践指向

Preparation and optical properties of solid solution semiconductor (Zn_xCd_(1-x)S) doped silica glasses

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Chinese Science Bulletin 1998年第1期43卷 78-81页

作者： shi Wensheng ZHANG Liangying YAO xi Electronic Materials Research Laboratory Xi’an Jiaotong UniversityXi’an 710049China

Semiconductor(Zn\-\%x\%Cd 1-x S) doped silica glasses were prepared by Sol_Gel process and \%in situ\% growth technique. The structure of the materials was characterized by X_ray diffraction technique, the particle size of semiconductor crystallites from X_ray patterns was estimated less than 10 nm. From absorption spectra, it is obtained that the absorption edges shifted to short wavelength diraction when Zn contents increased, and the absorption edge can be adjusted from 2.46 eV to 2.96 eV by controlling Zn contents. The third_order nonlinear optical susceptibility was studied at 532 nm with 8 ns pulse laser by degenerate four wave mixing (DFWM) technique.

关键词： Sol_Gel solid solution semiconductor(Zn\-\%x\%Cd 1-x S) nano_crystallite absorption edge.

Test of the Symmetrization Postulate for Phonons in an Ion Trap

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Chinese Physics Letters 2000年第6期17卷 391-392页

作者： ZHENG shi-Biao ZHU xi-Wen Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of Physics and MathematicsChinese Academy of SciencesWuhan 430071 Department of Electronic Science and Applied Physics Fuzhou UniversityFuzhou 350002

We propose a scheme for testing the symmetrization postulate(SP)for phonons in an ion trap,In the scheme a two-level ion is trapped in a harmonic potential and driven by a laser beam tuned to the *** violation of the SP is manifested by the probability that the ion makes a transition from the ground state to the excited state after an appropriate interaction time.

关键词： testing scheme harmonic

Remarks on convexity estimates for solutions of the torsion problem

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Science China Mathematics 2023年第5期66卷 1003-1020页

作者： xiaohan Jia xi-Nan Ma Shujun shi School of Mathematical Sciences Xiamen UniversityXiamen 361005China School of Mathematical Sciences University of Science and Technology of ChinaHefei 230026China School of Mathematical Sciences Harbin Normal UniversityHarbin 150025China

In this paper,for the solution of the torsion problem about the equation Δu=-2 with homogeneous Dirichlet boundary conditions in a bounded convex domain in Rn,we find a superharmonic function which implies the strict concavity of u ^(1/2) and give some convexity *** is a generalization of Makar-Limanov’s result(Makar-Limanov(1971))and Ma-shi-Ye’s result(Ma et al.(2012)).

关键词： convexity estimate superharmonicity maximum principle torsion problem

Proposal for Direct Measurement of the Wigner Function of a Cavity Field via Raman Coupling

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Chinese Physics Letters 2000年第12期17卷 882-884页

作者： ZHENG shi-Biao ZHU xi-Wen Department of Electronic Science and Applied Physics Fuzhou UniversityFuzhou 350002 Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan institute of Physics and MathematicsChinese Academy of SciencesWuhan 430071

We propose a scheme for the reconstruction of a cavity field *** the scheme the cavity field is first displaced by a microwave source,and then couples with a three-level A-type atom in a Raman *** an appropriate interaction time the measurement of the difference between the probabilities of the atom being in two ground states directly yields the Wigner function for the field *** scheme can be easily generalized to measure the Wigner function of an entangled state of two spatially separated single-mode cavities.

关键词： state. scheme Wigner

MESOPOROUS ACID SOLID AS A CARRIER FOR METALLOCENE CATALYST IN ETHYLENE POLYMERIZATION AND A CATALYST IN CATALYTIC DEGRADATION OF POLYETHYLENE

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Chinese Journal of Polymer Science 2007年第2期25卷 187-195页

作者： Wen-xi Cheng Li-ya shi shi-yun Li Hui Chen Tao Tang State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 China Graduate School of the Chinese Academy of Sciences Beijing 100039 China

The possibility of mesoporous acid solid as a carder for metallocene catalyst in ethylene polymerization and catalyst for polyethylene （PE） catalytic degradation was investigated. Here, HMCM-41 and AIMCM-41, and mesoporous silicoaluminophosphate molecular sieves （SAPO1 and SAPO2） were synthesized and used as acid solid. Much more gases were produced during catalytic degradation in PE/acid solid mixtures via in situ polymerization than those via physical mixing. The particle size distribution results exhibited that the particle size of SAPO1 in the PE/SAPOI mixture via in situ polymerization was about 1/14 times of that of the original SAPO1 or SAPO1-supported metallocene catalyst. This work shows a novel technology for chemical recycling of polyolefin.

关键词： Catalytic degradation Acid solids Supported metallocene catalysts Polyethylene.

Dynamical analysis and performance evaluation of a biped robot under multi-source random disturbances

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Acta Mechanica Sinica 2014年第6期30卷 983-994页

作者： Chun-Biao Gan Chang-Tao Ding shi-xi Yang The State Key Laboratory of Fluid Power Transmission and Control Department of Mechanical EngineeringZhejiang University

During bipedal walking,it is critical to detect and adjust the robot postures by feedback control to maintain its normal state amidst multi-source random disturbances arising from some unavoidable uncertain *** radical basis function（RBF）neural network model of a five-link biped robot is established,and two certain disturbances and a randomly uncertain disturbance are then mixed with the optimal torques in the network model to study the performance of the biped robot by several evaluation indices and a specific Poincar′e *** contrast with the simulations,the response varies as desired under optimal inputting while the output is fluctuating in the situation of disturbance *** results from noise inputting also show that the dynamics of the robot is less sensitive to the disturbance of knee joint input of the swing leg than those of the other three joints,the response errors of the biped will be increasing with higher disturbance levels,and especially there are larger output fluctuations in the knee and hip joints of the swing leg.

关键词： Biped robot Multi-source random disturbances Sensitive parameters RBF neural network Taguchi method Performance evaluation