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Non-ultrawide bandgap CsPbBr_(3) nanosheet for sensitive deep ultraviolet photodetection

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Journal of Materials Science & Technology 2023年第28期159卷 251-257页

作者： Chun-yan Wu Yu-Xuan Le li-yan liang Jing-Yue li Feng-Xia liang Shi-Rong Chen Xiao-Ping yang Yu-Xue Zhou lin-Bao Luo School of Microelectronics Hefei University of TechnologyHefei 230009China College of Physical Science and Technology Yangzhou UniversityYangzhou 225002China

In this study,we report the fabrication of a sensitive deep ultraviolet(DUV)photodetector by using CsPbBr_(3) nanosheets synthesized through confined-space growth at room *** peak pho-toresponse of the device upon illumination blueshifts with decreasing thickness and a 68 nm CsPbBr_(3) nanosheet based device displays a peak response to 265 nm illumination,showing responsivity and spe-cific detectivity of 85 mA/W and 4.05×1011 Jones at 3 V bias,*** simulation re-veals that the blueshift is associated with the wavelength-dependent absorption coefficient of CsPbBr_(3) nanosheet:incident light with shorter wavelengths can be absorbed on the superficial surface,while long-wavelength light has a larger penetration depth,leading to dominant DUV absorption in thinner CsPbBr_(3) *** work will shed light on the facile and cost-effective fabrication of DUV photode-tectors from non-ultrawide bandgap(UWBG)all-inorganic perovskite materials.

关键词： Non-ultrawide bandgap semiconductors CsPbBr_(3)nanosheet Wavelength-dependent absorption coefficient Sensitive DUV photodetector

Cure reaction and phase behavior of liquid crystalline epoxides-anhydride systems

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Chinese Chemical Letters 2007年第2期18卷 225-228页

作者： li yan liang Shao Ping Ren Yi Quan Zheng Man Geng Lu Guangzhou Institute of Chemistry Chinese Academy of SciencesGuangzhou 510650China Key Laboratory of Polymer Materials for Electronics Guangdong 510650China Graduate School of the Chinese Academy of Sciences Beijing 100049China

A series of novel liquid crystalline epoxides with lateral substituents were cured with anhydrides and the cure kinetics was investigated by non-isothermal DSC technique. The results showed that the lengths of lateral substituents have great effect on the value of Ea. The curing reaction became less active, when the liquid crystalline epoxides have long lateral substituents and were controlled by diffusion at the late stage of cure. A nematic structure was observed by POM and XRD.

关键词： liquid crystalline epoxy resin Anhydride Nematic phase Lateral substituent

Solubility of β-cyclodextrin in different mixed solvents

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Petroleum Science 2008年第3期5卷 263-268页

作者： Yu Yong li Jiguang Sun yan liang Qianqing Peng Xiaoming liu yansheng Hu Yufeng Laboratory of Green Chemistry and Chemical Engineering China University of Petroleum Beijing 102249 China

The solubility of β-cyclodextrin （β-CD） in ionic liquid/N, N-dimethyl-acetamide （IL/DMAC） mixed solvent and in liCI/DMAC mixed solvent was investigated at 323.15 K and 353.15 K. The results showed that the solubility of β-CD in IL/DMAC system increased with increasing temperature, but decreased in liCI/DMAC system. β-CD had the highest solubility in IL/DMAC system with [Cl]- or [Br]- anions. The solubility of β-CD in liCl/DMAC system was lower than that in IL/DMAC system with [Cl]- or [Br]- anions but higher than that in IL/DMAC system with weak-coordinated anions （e.g [BF4]- or [PF6]-）. The effects of substituent groups （benzyl and butyl） of cation and the structure of cations on β-cyclodextrin solubility were also investigated.

关键词： β-cyclodextrin ionic liquid solubility mixed solvent

Synthesis, Properties and Structureof a Novel Unsymmetrical Bis (phenoxo) BridgedBinuclear Copper (Ⅱ) Complex

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Chemical Research in Chinese Universities 2001年第2期17卷 148-152页

作者： LU Tong-bu , li yan-wu, FENG Xiao-long CAl Ji-wen, li Xiao-yan and JI liang-nian (Department of Chemistry and Center of Measurement, Zhongshan University, Guangzhou 510275, P. R. China) 中山大学广东广州 510275

A novel bis (phenoxo) bridged binuclear copper ( II) complex with dissimilar coordination environments was synthesized and characterized by spectroscopies and X-ray crystallography. It crystallized in the monoclinic system with space group C2/c, a=2. 241 1(2) nm, b=1. 834 2 (2) nm, c=1.877 9(2) nm, β=122.861(2)°, V=6.484 3(11) nm3, Z=8. Itconsistsof two unsymmetrical Cu (Ⅱ ) centers bridged by two phenolic oxygen atoms to yield a Cu2O2 core with the Cu-Cu separation of 0. 310 2 nm, in which Cul and Cu2 ions exhibit distorted N2O3 and N3O2 square pyramidal geometries, respectively.

关键词： Copper Binuclear complex Crystallization

Preparation of poly（N-isopropylacrylamide） brush grafted silica particles via surface-initiated atom transfer radical polymerization used for aqueous chromatography

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Frontiers of Materials Science 2012年第1期6卷 60-68页

作者： Zong-Jian liU yan-li liang Fang-Fang GENG Fang LV Rong-Ji DAI Yu-Kui ZHANG Yu-lin DENG School of life Science Beijing Institute of TechnologyBeijing 100081China Dalian Institute of Chemical Physics Chinese Academy of SciencesDalian 116023China

Thermoresponsive poly（N-isopropylacrylamide）（PNIPAAm） brushes were densely grafted onto silica surface via surface-initiated atom transfer radical polymeriza- tion （SI-ATRP）. The grafting reaction started from the surfaces of 2-bromoisobutyrate- functionalized silica particles in 2-propanol aqueous solution at ambient temperature using CuCIICuCI21N, N,N＇,N＇,N”.pentamethyldiethylenetriamine （PMDETA） as the catalytic system. Based on thermogravimetric analysis （TGA） results, the grafting amount and grafting density of PNIPAM chains on the surface of silica were calculated to be 1.29 mg/ m^2 and 0.0215 chains/nm^2, respectively. The gel permeation chromatography （GPC） result showed the relatively narrow molecular weight distribution （MwlMn= 1.21） of the grafted PNIPAAm. The modified silica particles were applied as high-performance liquid chromatography （HPLC） packing materials to successfully separate three aromatic compounds using water as mobile phase by changing column temperature. Temperature- dependent hydrophilic/hydrophobic property alteration of PNIPAAm brushes grafted on silica particles was determined with chromatographic interaction between stationary phase and analytes. Retention time was prolonged and resolution was improved with increasing temperature. Baseline separation with high resolution at relatively low temperatures was observed, demonstrating dense PNIPAAm brushes were grafted on silica surfaces.

关键词： poly(N-isopropylacrylamide) (PNIPAAm) atom transfer radical polymeriza-tion (ATRP) temperature-responsive chromatography separation

Study on the causes of local recurrence of rectal cancer after curative resection: analysis of 213 cases

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World Journal of Gastroenterology 1998年第6期4卷 72-74页

作者： YUAN Hong Yin, li yan, yanG Guo liang, BEI De Jiao and WANG Kun

AIM To study the local recurrent rate and the causes of rectal cancer after surgery. METHODS The clinicopathological data of 213 rectal cancer patients and the follow up information were analyzed. The overall recurrent rate and the recurrent rates from different surgical appreaches were calculated. The main causes of recurrence were investigated. RESULTS Among the 213 cases, 73 (34 27%) had local recurrence. The recurrent time ranged from 3 months to 62 months after the first operation. Most of the recurrence ( 65/73 , 89 04%) occurred within 3 years after operation. CONCLUSION Local recurrence had no significant correlation with surgical methods or pathological types, but closely related to Dukes′ stages, location of primary tumors and the length of the distal rectum resected. Early resection and a wide tumor free resection margin are key factors to prevent local recurrence.

关键词： rectal neoplasms/surgery Rectal neoplasms/pathology Neoplasm recurrent, local

Unveiling solid-solid contact states in all-solid-state lithium batteries:An electrochemical impedance spectroscopy viewpoint

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Journal of Energy Chemistry 2025年第2期101卷 16-22页

作者： Jin-liang li liang Shen Zi-Ning Cheng Jun-Dong Zhang ling-Xuan li Yu-Tong Zhang yan-Bin Gao Chunli Guo Xiang Chen Chen-Zi Zhao Rui Zhang Qiang Zhang Tsinghua Center for Green Chemical Engineering Electrification Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology Department of Chemical Engineering Tsinghua University College of Materials Science and Engineering Taiyuan University of Technology Advanced Research Institute of Multidisciplinary Science School of Materials Science and Engineering Beijing Institute of Technology Beijing Huairou Laboratory Institute for Carbon Neutrality Tsinghua University Shanxi Research Institute for Clean Energy Tsinghua University

All-solid-state lithium batteries（ASSLBs） are strongly considered as the next-generation energy storage devices for their high energy density and intrinsic *** solid-solid contact between lithium metal and solid electrolyte plays a vital role in the performance of working ASSLBs,which is challenging to investigate quantitatively by experimental *** work proposed a quantitative model based on the finite element method for electrochemical impedance spectroscopy simulation of different solid-solid contact states in *** the assistance of an equivalent circuit model and distribution of relaxation times,it is discovered that as the number of voids and the sharpness of cracks increase,the contact resistance Rcgrows and ultimately dominates the battery *** accurate fitting,inverse proportional relations between contact resistance Rcand（1-porosity） as well as crack angle was *** contribution affords a fresh insight into clarifying solid-solid contact states in ASSLBs.

关键词： All-solid-state lithium batteries Distribution of relaxation times Electrochemical impedance spectroscopy Equivalent circuit model Finite element method Solid-solid contacts

Trinuclear gold-catalyzed site-selective alkylation of peptides

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Science China Chemistry 2025年第1期68卷 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 MaterialsChemistry and Biomedicine Innovation Center(ChemBIC)School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China Green Catalysis Center College of ChemistryZhengzhou UniversityZhengzhou 450001China State Key Laboratory of Natural Medicines China Pharmaceutical UniversityNanjing 211198China

Selective modification of peptides has always been a challenging *** selective alkylation of peptides can alter the biological activity and physical properties of molecules,and it has gained significant research *** 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 theα-C(sp^(3))–H in glycine residue of *** 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 *** addition,mechanistic studies and density functional theory(DFT)calculations reveal an inner-sphere and subsequent outersphere single electron transfer(SET)mechanism.

关键词： gold catalysis peptide alkylation C-C coupling radical

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Holographic images of a charged black hole in Lorentz symmetry breaking massive gravity

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Science China(Physics,Mechanics & Astronomy) 2025年第2期68卷 59-72页

作者： Xiao-Xiong Zeng li-Fang li Pan li Bo liang Peng Xu College of Physics and Electronic Engineering Chongqing Normal UniversityChongqing 401331China Department of Mechanics Chongqing Jiaotong UniversityChongqing 400074.China Center for Gravitational Wave Experiment National Microgravity LaboratoryInstitute of MechanicsChinese Academy of SciencesBeijing 100190China Lanzhou Center of Theoretical Physics Lanzhou UniversityLanzhou 730000China

Using the AdS/CFT correspondence,this paper investigates the holographic images of a charged black hole within the context of Lorentz symmetry breaking massive *** photon rings,luminosity-deformed rings,or light points from various observational perspectives are *** also study the influences of both the chemical potential and temperature on the Einstein *** the previous work,which primarily examines the effect of chemical potential on ring radius at high temperatures and find no change in the radius with varying chemical potential,we also investigate the effect of chemical potential on the ring radius at low temperature besides at high *** findings indicate that at low temperatures,the photon ring radius decreases with increasing of chemical potential,while at high temperatures,the results are consistent with previous ***,we explore the impact of the model parameterλon the Einstein ring radius and find the the ring radius increases as the model parameterλ*** interestingly,for the large chemical potential,u=1,the temperature dependence of the photon ring radius is reversed forλ=2 andλ=***,for a small chemical potential u=0.1,the temperature dependence of the Einstein ring stays the same asλ=2 andλ=4.

关键词： AdS/CFT correspondence holographic images massive gravity black holes