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Trinuclear gold-catalyzed site-selective alkylation of peptides

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Science China Chemistry 2025年第1期 249-256页

作者： Qing-Yun Fang Chengyihan gu Yinghan Chen Wencheng Yan Yong Liang Weipeng Li Chengjian Zhu Jie Han Jin Xie State Key Laboratory of Coordination Chemistry Jiangsu Key Laboratory of Advanced Organic Materials Chemistry and Biomedicine Innovation Center (Chem BIC) School of Chemistry and Chemical Engineering Nanjing University Green Catalysis Center College of Chemistry Zhengzhou University State Key Laboratory of Natural Medicines China Pharmaceutical University

Selective modification of peptides has always been a challenging issue. The selective alkylation of peptides can alter the biological activity and physical properties of molecules, and it has gained significant research interest. We herein disclose an intriguing gold-catalyzed alkylation of peptides using bench-stable unactivated alkyl bromides under photoredox catalysis. A wide range of structurally diverse primary, secondary and tertiary alkyl bromides serve as effective coupling partners to precisely connect with the α-C(sp3)–H in glycine residue of peptides. This protocol demonstrates an exceptionally broad scope for alkyl halides and excellent tolerance for a wide range of useful functional groups. A series of relay transformations to construct cyclic peptides, to proceed click reaction and to realize peptide fluorescence labeling further enhance its synthetic practicality. In addition, mechanistic studies and density functional theory(DFT) calculations reveal an inner-sphere and subsequent outersphere single electron transfer(SET) mechanism.

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高压泡沫涨裂破岩特性试验研究

岩土工程学报 2025年第1期47卷 125-134页

作者：刘送永崔松顾聪聪中国矿业大学机电工程学院江苏徐州221116 中国矿业大学智能采矿装备技术全国重点实验室江苏徐州221116 安徽理工大学机电工程学院安徽淮南232001

针对钻爆法和机械法在岩石破碎工程中的弊端,基于泡沫的高黏性和可压缩性,提出了高压泡沫涨裂破岩技术。首先设计高压泡沫涨裂破岩装置,理论分析高压泡沫瞬间释放冲击岩石涨裂孔过程,搭建高压泡沫涨裂力测试装置并开展涨裂力影响试验,... 详细信息

针对钻爆法和机械法在岩石破碎工程中的弊端,基于泡沫的高黏性和可压缩性,提出了高压泡沫涨裂破岩技术。首先设计高压泡沫涨裂破岩装置,理论分析高压泡沫瞬间释放冲击岩石涨裂孔过程,搭建高压泡沫涨裂力测试装置并开展涨裂力影响试验,建立高压泡沫涨裂破岩试验系统,探讨不同空气体积分数时的泡沫涨裂特性,揭示高压泡沫涨裂破岩机理。研究表明:高压泡沫释放时,能够在涨裂孔内产生比泡沫初始压力更高的涨裂力,但涨裂力随泡沫空气体积分数增加而先增大后减小,高压泡沫涨裂破岩经历了裂纹初生、裂纹扩展、涨裂抛掷、涨裂结束4个阶段,破岩重量随泡沫空气体积分数的增加而先增大后减小,当空气体积分数为60%时,由高压泡沫冲击涨裂孔产生的压应力波在岩石上表面反射形成的拉应力造成岩石破坏形式为涨裂坑,空气体积分数为70%~90%时,泡沫涨裂形式为大块岩石分离,这主要是由孔底直角处应力集中效应造成。

关键词：高压泡沫涨裂破岩裂纹扩展涨裂力

A Note on Calculation of Phase Space Path Integral by Means of Invariants

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Communications in Theoretical Physics 2006年第5期45卷 813-814页

作者： QIAN Shang-Wu gu zhi-Yu physics Department Peking University Beijing 100871 China physics Department Capital Normal University Beijing 100037 China

In this note we use the method of invariant to calculate the phase space path integral appearing in our previous article.

关键词： phase space path integral invariant propagator

Polyethylenimine (PEI)g-comb-poly(ethylene glycol)-transferrin(I): Tumor-targeted Vector for Gene Delivery In-vitro

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Chinese Chemical Letters 2006年第1期17卷 113-116页

作者： gu Ping TANG zhi Yu WANG College of Life-Science. ZheJiang University Hangzhou 310028 Institute of Materials Research ＆ Engineering Singapore 3 Research Link 117602 The Second Hospital of Zhejiang University Hangzhou 310006

The work described the synthesis and evaluation of PEI-g-comb-PEG-transferrin as a potential system for gene therapy in vitro. The MW of PEG was 10KDa, and PEI was 2KDa. Its structure was identified by NMR, FT-IR and TGA spectroscopy. MTT assay found that at concentration up to 4000 n mol/L of the polymer, cell viability was over 85%. The bio-character of polymer/DNA complex was characterized by agarose gel electrophoresis, ethidium bromide exclusion and zeta-potential assay. The polymer could retardate DNA at N/P ratio 3.0-3.5 （mol/mol）. The particle size of the polymer/DNA complex was less than 300 nm. Transfection efficiency of the complex was studied in COS7 and NT2 cell lines.

关键词： PEI-g-Comb-PEG transferrin gene therapy transfection efficiency.

Knotted Picture of Unknown Quantum State in Process of Quantum Teleportation

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Communications in Theoretical Physics 2008年第5期49卷 1163-1164页

作者： gu zhi-Yu QIAN Shang-Wu Physics Department Capital Normal University Beijing 100037 China Physics Department Peking University Beijing 100871 China

This paper gives the knotted picture of the unknown quantum state in the process of quantum teleportation and the surgical knotted operations of the unitary operators operated on the teleported quantum state.

关键词： Bell bases single particle quantum state knotted picture flip operation inversion operation

Knotted Picture of Unitary Transformation Applied to Single Particle Quantum State

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Communications in Theoretical Physics 2008年第1期49卷 65-68页

作者： gu zhi-Yu QIAN Shang-Wu Physics Department Capital Normal University Beijing 100037 China Physics Department Peking University Beijing 100871 China

This paper introduces the unified expression of four Bell bases and uses the composition operation in knot theory to obtain the knotted picture of unitary operators based on Pauli operators, and gives the knotted expr... 详细信息

关键词： Bell bases composition operation knotted picture inversion relation

Relationship Between Two Classes of Shape-Invariant Potentials

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Communications in Theoretical Physics 2001年第10期36卷 391-394页

作者： QIAN Shang-Wu gu zhi-Yu Department of Physics Peking University Beijing 100871 China Department of Physics Capital Normal University Beijing 100037 China

We show that two classes of shape-invariant potentials are interrelated to each other. For all one-dimensional shape-invariant potentials with parameters related by translation, i.e. the first class of shapc-invariant potentials (SIP1),we can find their multi-parameter deformations with q acting as the deformation parameter, i.e. the second class of shape-invariant potentials (SIP2) with parameters related by scaling. In order to get closed solution of SIP2, we consider two infinitesimal intervals, one is close to q= 0 another close to q = 1, and show that in these intervals we can get separately two first-order approximate solutions in closed form, furthermore we prove that all SIP1 can be obtained by the limiting procedures for corresponding SIP2.

关键词： shape-invariant potential, superpotential, multi-parameter deformation

Evolutions of Yang Phase Under Cyclic Condition and Adiabatic Condition

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Communications in Theoretical Physics 2005年第2X期44卷 243-246页

作者： QIAN Shang-Wu gu zhi-Yu Physics Department Peking University Beijing 100871 China Physics Department Capital Normal University Beijing 100037 China

There are three non-integrable phases in literatures: Berry phase, Aharonov-Anandan phase, and Yang phase. This article discusses the evolutions of Yang phase under the cyclic condition and the adiabatic condition for the generaltime-dependent harmonic oscillator, thus reveals the intimate relations between these three non-integrable phases.

关键词： Berry phase A-A phase Yang phase general time-dependent harmonic oscillator

New degradation call admission control for increasing WCDMA system capacity

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Journal of Systems Engineering and Electronics 2006年第4期17卷 750-754页

作者： Liu Ningqing Lu zhi gu Xuemai Dept. Electronics and Communication Engineering Harbin Inst. of Technology Harbin 150001P.R. China

Propose a new degradation call admission control（DCAC）scheme, which can be used in wideband code division multiple access communication system. So-called degradation is that non-real time call has the characteristic of variable bit rate, so decreasing its bit rate can reduce the load of the system, consequently the system can admit new call which should be blocked when the system is close to full load, therefore new call＇s access probability increases. This paper brings forward design project and does system simulation, simulation proves that DCAC can effectively decrease calls＇ blocking probability and increase the total number of the on-line users.

关键词： degradation call admission control WCDMA call block probability.