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Chinese Journal of Structural Chemistry 1999年第2期18卷 49-55页

作者： Gong, xd Xiao, HM Dong, HS Nanjing Univ Sci & Technol Dept Chem Nanjing 210094 Peoples R China China Acad Engn Phys Inst Chem Mat Mianyang 610003 Peoples R China

The molecular geometries and electronic structures of two isomers of benzotrifuroxan (BTF) have been studied using ab initio molecular orbital method at the HF/6 31G * level. The calculated results show that the hexanitroso isomer has much higher energy than the tetracyclic form and is unstable. Infrared frequencies have been calculated for the stable tetracyclic structure and scaled by 0.89. The scaled frequencies agree well with the available experimental results, and have been used to derive the standard thermodynamic functions, heat capacity( Cp °), entropy( S °) and enthalpy( H° H 298 °).

关键词： benzotrifuroxan(BTF) ab initio MO method molecular geometry electronic structure IR frequency thermodynamic property

Rh(Ⅲ)-catalyzed late-stage C-H alkenylation and macrolactamization for the synthesis of cyclic peptides with unique Trp(C7)-alkene crosslinks

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Chinese Chemical Letters 2024年第8期35卷 270-277页

作者： Shulei Hu yu Zhang Xiong Xie Luhan Li Kaixian Chen Hong Liu Jiang Wang Department of Medicinal Chemistry School of PharmacyChina Pharmaceutical UniversityNanjing 211198China State Key Laboratory of Drug Research Shanghai Institute of Materia MedicaChinese Academy of SciencesShanghai 201203China Lingang Laboratoty Shanghai 200031China School of Life Science and Technology ShanghaiTech UniversityShanghai 200031China

Heterocycle-braced cyclic peptides have demonstrated enhanced metabolic stability,increased potency and ***,we present a rapid synthesis method for constructing Trp(C7)-alkene(E)-crosslinked cyclic peptides with potent anti-proliferative activities against cancer cells,through C-H alkenylation and *** report addresses critical challenges associated with the installation and removal of the directing group N-Piv,configuration selectivity of the olefin,and intramolecular ***-tably,this method exhibits mild reaction conditions,traceless removal of the directing group,and high configuration selectivity.

关键词： C-H functionalization Rh(Ⅲ)-catalyzed Alkenylation Cyclic peptides Macrolactamization

A New Triterpenoid Glycoside from Dichotomanthes tristaniaecarpa

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Chinese Chemical Letters 2000年第11期11卷 1013-1014页

作者： Mei, WL Luo, xd Chen, CX Acad Sinica Kunming Inst Bot Lab Phytochem Kunming 650204 Peoples R China

A new triterpenoid glycoside 1, 1 beta, 2 alpha, 3 alpha, 19 alpha -tetrahydroxyurs-12-en-28-oic acid beta -D glucopyranosyl ester was isolated from Dichotomanthes tristaniaecarpa. The structure was elucidated on the ... 详细信息

关键词： triterpenoid glucoside Dichotomanthes tristaniaecarp Rosaceae

Long-range Correlations in Iodide Cluster Aggregates

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Journal of Materials Science & Technology 1997年第4期13卷 271-273页

作者： Zhang, JZ Yang, xd Li, HD Ye, XY TSING HUA UNIV DEPT CHEMBEIJING 100084PEOPLES R CHINA

The morphology of tin iodide deposits grown during gas-solid transformation demonstrated long-range correlations. These iodide deposits include basically two kinds of forms: fractal structure and dendritic-like structure. The fractal structure was a sort of tin iodide cluster aggregation. Each fractal structure was composed of numerous tin iodide clusters that connected or disconnected with each other. The average size of fractal structures is between 10 and 22 mu m. The dendritic-like structure was also composed of many tin iodide clusters. These clusters aggregated and formed a dendritic pattern.

关键词： Iodine compounds

Pars plana vitrectomy for retinal detachment using perfluoro-n-octane as intraoperative tamponade:a multicenter,randomized,non-inferiority trial

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International Journal of Ophthalmology(English edition) 2024年第1期17卷 82-91页

作者： Xin Shi Wei-Jun Wang Ying Fan Hai-yun Liu Hong Wang yu-Hui Chen Ao Rong Zhi-Feng Wu Xun Xu Kun Liu Department of Ophthalmology Shanghai General HospitalShanghai Jiao Tong University School of MedicineNational Clinical Research Center for Eye DiseasesShanghai Key Laboratory of Ocular Fundus DiseasesShanghai Engineering Center for Visual Science and PhotomedicineShanghai Engineering Center for Precise Diagnosis and Treatment of Eye DiseasesShanghai 200085China Shanghai Jieshi Medical Technology Co.Ltd. Shanghai 201201China Department of Ophthalmology Tongji HospitalSchool of MedicineTongji UniversityShanghai 200065China Department of Ophthalmology Wuxi No.2 People’s Hospital(Jiangnan University Medical CenterJUMC)Wuxi 214002Jiangsu ProvinceChina

AIM:To evaluate the efficacy and safety of perfluoro-n-octane(PFO)for ophthalmic surgery versus F-Octane as an intraoperative tamponade in pars plana vitrectomy(PPV)in management of retinal ***:This multicenter,prospective,randomized,double-masked,parallel-controlled,non-inferiority trial was conducted in three ophthalmology clinical centers in *** with retinal detachment,who were eligible for PPV were consecutively *** were assigned to PFO for ophthalmic surgery or F-Octane for intraocular tamponade in a 1:1 ***-corrected visual acuity(BCVA),intraocular pressure(IOP)measurement,and dilated fundus examination were performed preoperatively and at 1,7±1,28±3d *** primary outcome was complete retinal reattachment rate at postoperative day *** non-inferiority margin was set at 9.8%.The secondary outcomes included intraoperative retinal reattachment rate,and mean changes in IOP and BCVA from baseline to 1,7±1,28±3d postoperatively,*** analyses were presented for all randomly assigned participates in this ***:Totally 124 eligible patients completed the study between Mar.14,2016 and Jun.7,*** of them were randomly assigned to the PFO for ophthalmic surgery group,and 64 were assigned to the F-Octane *** characteristics were comparable between the two *** groups achieved 100%retinal reattachment at postoperative day one(difference 0,95%CI:-6.21%to 5.75%,P=1).The pre-defined noninferiority criterion was *** significant difference was observed in intraoperative retinal reattachment rate(difference 1.77%,P=0.61),mean changes in IOP(difference 0.36,-0.09,2.22 mm Hg at 1,7±1,28±3d postoperatively,with all P>0.05)and BCVA(difference 0.04,-0.02,0.06 logMAR at 1,7±1,28±3d postoperatively,all P>0.05)between the two *** apparent adverse events related to the utilization of PFO were ***:In patients with retinal detachment undergoing PPV,PFO

关键词： perfluoro-n-octane vitreoretinal surgery intraocular tamponade ophthalmic surgery retinal detachment

SIMULATION OF THE THERMODYNAMIC QUANTITIES OF SELF-AVOIDING WALK CHAIN

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Chinese Chemical Letters 1996年第1期7卷 63-66页

作者： Zhao, DL Zhou, xd Huang, Y ACAD SINICA INST CHEMBEIJING 100080PEOPLES R CHINA BEIJING UNIV DEPT PHYSBEIJING 100871PEOPLES R CHINA

A Monte Carlo method has been proposed for direct simulating the thermodynamic quantities of a single self-avoiding walk chain with the neighbour interaction on a simple cubic lattice. The simulation data of the conformational entropy of the chain length 16 have been found to be consistent very well with the exact results obtained by the direct counting method.

关键词： CARLO

Carbide Behavior during High Temperature Creep in DZ40M Co-base Superalloy

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Journal of Materials Science & Technology 1999年第6期15卷 515-518页

作者： Jiang, WH Yao, xd Guan, HR Hu, ZQ Chinese Acad Sci Inst Met Res Shenyang 110015 Peoples R China

The carbide behavior of a directionally solidified Co-base superalloy DZ40M has been investigated after creep at 700 degrees C and 900 degrees C. During the high temperature creep, a great amount of secondary carbide, M23C6 precipitated in alloy matrix. At 700 degrees C, the M23C6 precipitation occurred in slip bands, indicating that it was stress-induced, while at 900 degrees C, M23C6 formed surrounding the primary carbides, which is a characteristic of thermally aged alloy. The M23C6 particles pinned up dislocations and subgrain boundaries, strengthening the alloy matrix effectively. The creep crack initiation of DZ40M alloy was exclusively related to the primary carbides. The fracture of the primary carbide and the crack at the interface between them and matrix resulted in the crack formation. Furthermore, it was found that at 900 degrees C, the surface of specimens was oxidized severely and the preferentially oxidized primary carbides acted as crack initiation sites.

关键词： Superalloys

The Mechanism of the Initial Dark Oxidation of Ethers and the Ether-Oxygen Contact Charge Transfer Complex

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Chinese Chemical Letters 1997年第10期8卷 869-872页

作者： Zhu, JM Cao, WX Feng, xd BEIJING UNIV COLL CHEM & MOL ENGNBEIJING 100871PEOPLES R CHINA

The contact charge transfer (CCT) absorption spectra of isopropyl ether, phenyl isopropyl ether and benzyl isopropyl ether with oxygen were measured. The mechanism of the initial dark oxidation of different ethers via... 详细信息

关键词： De The Mechanism of the Initial Dark Oxidation of Ethers and the Ether-Oxygen Contact Charge Transfer Complex

Mechanical, Thermal, Morphological and RheologicalProperties of Polypropylene/Ultrahigh Molecular Weight Polyethylene Blends

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Journal of Materials Science & Technology 1995年第1期11卷 46-52页

作者： WANG, xd JIN, RG LI, HQ

In this study, the blends of polypropylene (PP) and ultrahigh molecular weight polyethylene (UHMWPE) were prepared by the four- and twin-screw extruders, and ethylene-propylene-diene monomer (EPDM), as the third component, was added to the binary blends. The mechanical, thermal, morphological and rheological properties of these two blends have been investigated. For the materials blended by the four-screw extruder, a 15 wt-% content oi UHMWPE corresponds to a maximum lzod impact strength, and the miscibility enhancement effect of EPDM on PP/UHMWPE blends is very remarkable. Mechanical and thermal properties demonstrate that melt blending by the four-screw extruder is a better processing method for PP/UHMWPF blends than that by the twin-screw extruder, A co-continuous structure was observed in blends through TEM, acid a novel ''linear interpenetrating'' toughening mechanism is proposed on the basis of this research work.

关键词： BEHAVIOR

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片上红外偏振探测研究进展

红外与毫米波学报 2024年第1期43卷 52-62页

作者：甄玉冉邓杰布勇浩代旭余宇石梦碟王若文叶韬陈刚周靖中国科学院上海技术物理研究所红外物理国家重点实验室上海200083 中国科学院大学北京100049

偏振是光的固有自由度,偏振探测提供了光强和波长之外的更多丰富信息。红外偏振探测器在成像、通信、遥感和宇宙学等众多应用中发挥着至关重要的作用。然而,传统的偏振检测系统体积庞大、系统复杂,阻碍了偏振探测的小型化和集成化。近来... 详细信息

偏振是光的固有自由度,偏振探测提供了光强和波长之外的更多丰富信息。红外偏振探测器在成像、通信、遥感和宇宙学等众多应用中发挥着至关重要的作用。然而,传统的偏振检测系统体积庞大、系统复杂,阻碍了偏振探测的小型化和集成化。近来,片上红外偏振探测器的发展引起了广泛的研究兴趣。本文将重点介绍片上红外偏振探测器的两个前沿研究领域:偏振敏感材料和偏振选择性光耦合结构集成的红外偏振探测器,主要讨论片上红外偏振探测器的研究现状以及未来的挑战和机遇。

关键词：红外偏振探测器各向异性材料拓扑材料手性钙钛矿偏振选择性光学耦合结构