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Chinese Journal of Structural Chemistry 2007年第2期26卷 229-233页

作者： han xiang-yun zheng qing Department of Chemical Engineering YanchengInstitute of Technology Jiangsu 224003 China

Geometrical configurations of 16 substituted biphenyls were computed at the B3LYP/6-311G^＊＊ level with Gaussian 98 program. Based on linear solvation energy theory, lgKow as well as the structural and thermodynamic parameters obtained at this level was taken as theoretical descriptors, and corresponding equation predicting the toxicity of Daphnia magna （-lgEC5o） was thus obtained, in which three parameters were contained, i.e., n-octanol/water partition coefficients （lgKow）, dipole moment of the molecules（ μ） and entropy （S°）. For this equation, R^2 = 0.9582, q^2 = 0.8921 and SD = 0.102. The absolute t-scores of three variables are larger than the standard one in the confidence range of 95%, which confirms the creditability and stability of this model.

关键词： substituted biphenyl linear solvation energy theory,DFT method Daphnia magna toxicity

A cellulose-based lithium-ion battery separator with regulated ionic transport and high thermal stability for extreme environments

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Nano Research 2025年第1期18卷 315-322页

作者： Kun-Peng Yang Song Xie Zi-Meng han Hao-Cheng Liu Chong-han Yin Wen-Bin Sun Zhang-Chi Ling Huai-Bin Yang De-han Li qing-Fang Guan Shu-Hong Yu Department of Chemistry New Cornerstone Science LaboratoryInstitute of Biomimetic Materials&ChemistryAnhui Engineering Laboratory of Biomimetic MaterialsDivision of Nanomaterials&ChemistryHefei National Research Center for Physical Sciences at the MicroscaleUniversity of Science and Technology of ChinaHefei 230026China Institute of Innovative Materials Department of Materials Science and EngineeringDepartment of ChemistrySouthern University of Science and TechnologyShenzhen 518055China

Separators play a critical role in lithium-ion ***,the restrictions of thermal stability and inferior electrical performance in commercial polyolefin separators significantly limit their applications under harsh ***,we report a cellulose-assisted self-assembly strategy to construct a cellulose-based separator massively and *** an ultrahigh ionic conductivity in electrolytes of 3.7 mS·cm^(-1) and the ability to regulate ion transport,the obtained separator is a promising alternative for high-performance lithium-ion *** addition,integrated with high thermal stability,the cellulose-based separator endows batteries with high safety at high temperatures,greatly expanding the application scenarios of energy storage devices in extreme environments.

关键词： lithium-ion batteries bio-inspired materials battery separators cellulose nanofiber ultrahigh ionic conductivity high safety

Production representation of partial wave scattering amplitudes and the fo（600） particle

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Frontiers of physics 2013年第5期8卷 540-547页

作者： han-qing zheng Department of Physics and State Key Laboratory of Nuclear Physics and Technology Peking University Beijing 100871 China

The establishlnent of production representation of partial wave scattering alnplitudes is reviewed in the context of quantum field theory. Its relation to the production representation, or Ning Hu representation in quantum mechanical scattering theory is pointed out. One of the most important application of the production representation is the physics of the fo（600） and K（700） scalar hadron resonances, on which we also give a brief review. It is emphasized that all evidences accunmlated so far are consistent with the picture that the fo（600） meson is the chiral partner of the Nambu Goldstone bosons in a linear realization of chiral symmetry.

关键词： scalar mesons chiral symmetry unitarization

Discovery of first active breeding den of Chinese mountain cat(Felis bieti)

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Zoological Research 2020年第3期41卷 341-344页

作者： Xue-Song han Huai-qing Chen zheng-Yi Dong Ling-yun Xiao xiang Zhao Zhi Lu Shan Shui Conservation Center Peking UniversityBeijing 100871China Center for Nature and Society School of Life SciencesPeking UniversityBeijing 100871China

DEAR EDITOR,In mid-September 2018,during a field survey in Chiat'ung,Sanjiangyuan(Three-River-Source)Region,Tibetan Plateau,China,we discovered the first active breeding den of the Chinese mountain cat(Felis bieti),inhabited by one adult female and two *** on fieldwork over the following months,five breeding dens were discovered,and 33 sightings were recorded.

关键词： breeding Plateau den

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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A Study of ρ-ω Mixing in Resonance Chiral Theory

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Communications in Theoretical Physics 2018年第1期69卷 50-58页

作者： yun-Hua Chen De-Liang Yao han-qing zheng School of Mathematics and Physics University of Science and Technology BeijingBeijing 100083China Instituto de Fisica Corpuscular(Centro Mixto CSIC-UV) Institutos de Investigaci6n de PaternaApartado 2208546071 ValenciaSpain Department of Physics and State Key Laboratory of Nuclear Physics and Technology Peking UniversityBeijing 100871China Collaborative Innovation Center of Quantum Matter Beijing 100871China

The strong and electromagnetic corrections toρ-ωmixing are calculated using an SU(2)version of resonance chiral theory up to next-to-leading orders in 1/N_(C)expansion,*** to our accuracy,the effect of the momentum dependence ofρ-ωmixing is incorporated due to the inclusion of loop *** analyze the impact ofρ-ωmixing on the pion vector form factor by performing numerical fit to the data extracted from e^(+)e^(-)→π^(+)π^(-)andτ→ν_(τ)2π,while the decay width ofω→π^(+)π^(-)is taken into account as a *** is found that the momentum dependence is significant in a good description of the experimental *** addition,based on the fitted values of the involved parameters,we analyze the decay width ofω→π^(+)π^(-),which turns out to be highly dominated by theρ-ωmixing effect.

关键词： Chiral Lagrangians vector mesons 1/N_(C)expansion

Nitric Oxide Regulates Dark-Induced Leaf Senescence Through EIN2 in Arabidopsis

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Journal of Integrative Plant Biology 2012年第8期54卷 516-525页

作者： yun-han Niu Fang-qing Guo The National Key Laboratory of Plant Molecular Genetics and National Center for Plant Gene Research(Shanghai) Institute of Plant Physiology&EcologyShanghai Institutes for Biological Sciencesthe Chinese Academy of SciencesShanghai 200032China

The nitric oxide （NO）-deficient mutant nosllnoal exhibited an early leaf senescence phenotype. ETHY- LENE INSENSITIVE 2 （EIN2） was previously reported to function as a positive regulator of ethylene- induced senescence. The aim of this study was to address the question of how NO interacts with ethylene to regulate leaf senescence by characterizing the double mutant ein2-1 nosllnoal （Arabidopsis thaliana）. Double mutant analysis revealed that the nosllnoal-mediated, dark-induced early senescence phenotype was suppressed by mutations in EIN2, suggesting that EIN2 is involved in nitric oxide signaling in the regulation of leaf senescence. The results showed that chlorophyll degradation in the double mutant leaves was significantly delayed. In addition, nosllnoal-mediated impairment in photochemical efficiency and integrity of thylakoid membranes was reverted by EIN2 mutations. The rapid upregulation of the known senescence marker genes in the nosl/noal mutant was severely inhibited in the double mutant during leaf senescence. Interestingly, the response of dark-grown nosl/noal mutant seedlings to ethylene was similar to that of wild type seedlings. Taken together, our findings suggest that EIN2 is involved in the regulation of early leaf senescence caused by NO deficiency, but NO deficiency caused by NOSIlNOA1 mutations does not affect ethylene signaling.

关键词： Arabidopsis dark EIN2 leaf senescence nitric oxide.

Singularities and accumulation of singularities ofπN scattering amplitudes

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Communications in Theoretical Physics 2022年第11期74卷 136-139页

作者： Qu-Zhi Li han-qing zheng Department of Physics Peking University Beijing 100871China College of Physics Sichuan UniversityChengduSichuan 610065China Collaborative Innovation Center of Quantum Matter BeijingChina

It is demonstrated that for the isospin I=1/2πN scattering amplitude,T^(I=1/2)(s,t),s=(m_(N)^(2)-m_(π)^(2))^(2)/m_(N)^(2)and s=m_(N)^(2)+2m_(π)^(2)are two accumulation points of poles on the second sheet of complex s plane,and are hence accumulation of singularities of T^(I=1/2)(s,t).For T^(I=3/2)(s,t),s=(m_(N)^(2)-m_(π)^(2))^(2)/m_(N)^(2)is the accumulation point of poles on the second sheet of the complex s *** proof is valid up to all orders of chiral expansions.

关键词： dispersion relations partial wave analyticity

Use of Dispersion Relations in ππ and KK^- Coupled-Channel System

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Communications in Theoretical Physics 2007年第4X期48卷 685-694页

作者： XIAO Zhi-Guang zheng han-qing Department of Physics Peking University Beijing 100871 China

Systematic and careful studies are made on the properties of the IJ =00 7rTr and KK^- coupled-channel system, using newly derived dispersion relations between the phase shifts and poles and cuts. The effects of nearby... 详细信息

关键词： ππ scattering

Studying High Energy Final State Interactions by N/D Method

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Chinese Physics Letters 2000年第7期17卷 475-477页

作者： YUAN Feng zheng han-qing Department of Physics Peking UniversityBeijing 100871

We discuss the final state interaction effects at high energies via a multi-channel N/D method. We find that a 2 by 2 charge-exchange final state rescattering typically contributes an enhancement factor of a few times 10-2 in the B meson decay amplitude, for both the real and theimaginary parts. We also make some discussions on the elastic rescattering effects.

关键词： method imaginary discussions