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Regioselective etherification of 1,2-O-isopropylidene-4,6-di-O-benzyl myo-inositol

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Chinese Journal of Chemistry 1996年第3期14卷 271-278页

作者： Yuan, CY Zhai, hx Li, SS ACAD SINICA SHANGHAI INST ORGAN CHEMSHANGHAI 200032PEOPLES R CHINA

During the etherification of 1,2-O-isopropylidene-4,6-di-O-benzyl myo-inositol, the specific regioselectivity on 3- or 8-hydroxyl group was showed to be determined by the nature of the O-alkylating agents used. As demonstrated by MM and MNDO calculation, the regioselectivity of the reaction mentioned can be rationalized by steric and/or electronic effect.

关键词： regioselective etherification myo-inositol MM and MNDO calculation

A NEW EUDESMANE SESQUITERPENE FROM THE ROOT OFRHAPONTICUM UNIFLORUM

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Chinese Chemical Letters 1995年第2期6卷 111-112页

作者： Cheng, DL Wei, hx Cheng, JK Lanzhou Univ Dept Chem Natl Lab Organ Chem Lanzhou 730000 Peoples R China New Med & Pharmaceut Inst Gansu Prov Lanzhou 730050 Peoples R China

A new eudesmane sesquiterpene was isolated from the root of Rhaponticum uniflorum (Compositae) and Its structure was elucidated on the basis of spectra method (IR, EIMS, H-1-NMR, C-13-NMR, DEPT and H-1, H-1-Cosy) as 7... 详细信息

关键词： ROOT A NEW EUDESMANE SESQUITERPENE FROM THE ROOT OFRHAPONTICUM UNIFLORUM

Synthesis of A Novel Aluminosilicate with Bimodal Mesopore Distribution

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Chinese Chemical Letters 1997年第10期8卷 927-930页

作者： Yuan, ZY Wang, JZ Li, hx Chang, ZX NANKAI UNIV DEPT CHEMCATALYSIS LABTIANJIN 300071PEOPLES R CHINA SINOPEC FUSHUN RES INST PETR & PETROCHEMFUSHUN 113001PEOPLES R CHINA

A novel aluminosilicate with well-defined bimodal mesopore distribution has been synthesized directly, in which one mesopore is distributed at around 3.8nm and the other at 2.6nm.

关键词： MSU Nature Synthesis of A Novel Aluminosilicate with Bimodal Mesopore Distribution SBA

Synthesis and Electrochemical Studies on BEDT-TTF Derivatives with Hydroxyl Groups

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Chinese Chemical Letters 2000年第10期11卷 883-886页

作者： Li, hx Zhang, DQ Xu, W Zhu, DB Chinese Acad Sci Ctr Mol Sci Organ Solids Lab Inst Chem Beijing 100080 Peoples R China

New electron donors with hydroxyl groups were synthesized and characterized spectroscopically. Their redox potentials were determined with cyclic voltammetry, and the comparison with BEDT-TTF [Bis(ethylenedithio)tetrathiafulvalene] in this aspect was made. These results indicated that the new electron donors had similar electron-donating capabilities as BEDT-TTF.

关键词： electron donor hydroxyl group hydrogen bond redox potential

THE　SYNTHESIS　OF　ARYLOXY－CARBOXYLIC　ACID　UNDER　MICROWAVE，SOLID　BASE　AS　A　SUPPORT

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Chinese Chemical Letters 1996年第6期7卷 527-530页

作者： Wang, ZY Shi, HJ Shi, hx Zhang, ZY ANHUI NORMAL UNIV DEPT CHEMWUHU 241000ANHUIPEOPLES R CHINA LANZHOU UNIV DEPT CHEMLANZHOU 730000PEOPLES R CHINA

A series of aryloxy-abet ic acids were synthesiedby the react ion of subst nuted plenols with cbloroaceticac id under the condit ion of microwave irradiation and withsol id base as a support. Tits method haB the advan... 详细信息

关键词： ACID CARBOXYLIC UNDER MICROWAVE SOLID AS ARYLOXY

基于格网尺度的黄河中游地区经济城镇化与PM_(2.5)浓度的脱钩关系研究

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生态经济 2025年第1期41卷 132-139页

作者：沈威曹威威洛阳师范学院地理与旅游学院河南洛阳471022 河南大学地理与环境学院河南开封475004

针对当前经济城镇化参量公里网格数据的缺乏,以黄河中游地区为例,提出一种利用1995—2018年高精度土地利用栅格数据和统计年鉴数据的经济城镇化参量空间化模拟方法,并分析格网尺度下黄河中游地区经济城镇化与PM2.5浓度的脱钩关系演变。... 详细信息

针对当前经济城镇化参量公里网格数据的缺乏,以黄河中游地区为例,提出一种利用1995—2018年高精度土地利用栅格数据和统计年鉴数据的经济城镇化参量空间化模拟方法,并分析格网尺度下黄河中游地区经济城镇化与PM2.5浓度的脱钩关系演变。结果表明:(1)黄河中游地区经济城镇化水平呈现出以兰西城市群、西安城市圈、太原城市圈、郑州—洛阳城市带为核心的多核心圈层结构。(2)在空间格局演变上,不同区域经济城镇化的扩张模式存在差异。受地形限制和水文条件限制,洛河流域、汾河流域、关中平原、太原城市圈经济城镇化呈现以中心城市为核心的带状扩张特征;兰西城市群、郑州—洛阳城市带、呼和浩特市呈现以中心城市为核心的圈层式扩张特征。(3)2005年之后,黄河中游中东部地区开始出现脱钩转折点;2010年之后,黄河中游西部地区开始出现脱钩转折点,但由于西部大开发战略的实施,导致2015—2018年甘肃和宁夏南部扩张负脱钩区面积显著增加,经济城镇化与环境污染的脱钩关系再次发生转变。

关键词：经济城镇化土地利用回归模型 PM2.5浓度脱钩状态

Room-Temperature Synthesis of Fe-containing Mesoporous Silica

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Chinese Chemical Letters 1996年第11期7卷 1057-1058页

作者： Yuan, ZY Chen, TH Wang, JZ Li, hx NANKAI UNIV DEPT CHEMTIANJIN 300071PEOPLES R CHINA

A Fe-containing mesoporous silica has been synthesized at room temperature using alkylamine as templating surfactant; XRD, IR, ESR and Si-29 MAS NMR spectra provided evidence of the presence of framework and non-frame... 详细信息

关键词： Fe Room-Temperature Synthesis of Fe-containing Mesoporous Silica

Cerebral fat embolism following autologous fat injection in facial reconstruction:A case report

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World Journal of Clinical Cases 2025年第2期13卷 50-58页

作者： Xiu-Ying Chen Fa shen Chang Cheng Yu-Han Wang Wen-Chao Cheng De-Zhi Yuan Wen Huang Department of Neurology Chongqing Emergency Medical CenterChongqing University Central HospitalChongqing 400000China Department of Neurology Xinqiao HospitalThe Army Medical University(Third Military Medical University)Chongqing 400000China

BACKGROUND Autologous fat injection in facial reconstruction is a common cosmetic *** cerebral fat embolism(CFE)as a complication is rare,it carries serious health *** SUMMARY We present a case of a 29-year-old female patient who developed acute CFE following facial fat filling *** the surgery,the patient experienced symptoms including headache,nausea,vomiting,and difficulty breathing,which was followed by neurological symptoms such as slurred speech and left-sided *** physical examination and auxiliary investigations,including blood tests,head and neck computed tomography angiography,and cranial magnetic resonance diffusion-weighted imaging,were performed upon *** clinical diagnosis was acute cerebral embolism following facial fat filling *** included measures to improve cerebral circulation,dehydration for intracranial pressure reduction,nutritional support,and rehabilitation therapy for left limb *** patient showed a significant improvement in symptoms after 2 weeks of *** recovered left limb muscle strength to grade 5,had clear speech,and experienced complete relief of *** Our case highlights the potential occurrence of severe complications in patients undergoing fat injection in facial *** prevent these complications,plastic surgeons should enhance their professional knowledge and skills.

关键词： Cerebral fat embolism Mechanical thrombectomy Thrombolysis Steroid therapy Symptomatic treatment Case report

Synthesis　and　Characterization　of　Thermotropic　Liquid　Crystalline　Complexes　Containing　Ferrocenyl　Group

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Chinese Chemical Letters 1996年第11期7卷 1039-1040页

作者： Liu, ZM Lian, W Shi, hx Niu, T Lia, XS NEIMENGGU UNIV DEPT CHEMHOHHOT 010021PEOPLES R CHINA

Four ferrocenyl long -chain alkyl β-diketonato zinc(Ⅱ) complexes with a general formulaZnL2 (L = C5H5FeC5an COCH COCnH2n+1.n= 6 - 9) were synthesized. These complexes were characterizedby elementary analysis, IR 1HNMR MS. polarizing microscopy with a heating stage and DSC. It wasfound that the complexes have thermotropic liquid crystalline properties. The type of the heteronuclearliquid crystalline metal complexes have not been reported so far.

关键词： Thermotropic Liquid and Complexes Characterization