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Chinese Chemical Letters 2006年第1期17卷 1-4页

作者： Wei Min ZHU zhi fang li Yong Min ZHANG Department of Chemistry Zhejiang University Xixi Campus Hangzhou 310028 State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Sciences Shanghai 200032

Enamines, promoted by the samarium/samarium diiodide mixed reagent, were synthesized via the cross-coupling of thioamides and diarylketones in good yields.

关键词： Samarium enamines cross-coupling thioamides diarylketones.

Correlation between Polymerization of Cyclic Butylene Terephthalate(CBT) and Crystallization of Polymerized CBT

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Chinese Journal of Polymer Science 2015年第8期33卷 1104-1113页

作者：张建强 zhi-fang li Zheng Zhang Hui-xia Feng Zong-bao Wang Ya li Peng Chen 顾群 School of Petrochemical Technology Lanzhou University of Technology Faculty of Materials Science and Chemical Engineering Ningbo University Institute of Material Engineering Ningbo University of Technology Ningbo Key Laboratory of Polymer Materials Ningbo Institute of Material Technology and EngineeringChinese Academy of Sciences

The correlation between ring-opening polymerization （ROP） of cyclic butylene terephthalate （CBT） and crystallization of polymerized CBT （pCBT） strongly affected the final properties of pCBT and its composites. The major objective of this contribution is to pinpoint the threshold temperature between them and the interrelation is successfully disclosed. That is, crystallization during polymerization occurs below 204 ℃ and the crystallization properties of pCBT are determined by this isothermal ROP stage; polymerization and crystallization are gradually separated with the increase of temperature of ROP （Tp） from 204 ℃, and the crystallization properties of pCBT are dominated by cooling stage; only polymerization is performed above 212 ℃. Moreover, quantitative analysis suggests that uniform crystal size distributions and thicker lamellar crystals derive from the stage of crystallization during polymerization. On the contrary, the crystal size distributions become wider above 204 ℃ of Tp and lead to obvious double melting peaks during heating scan. These efforts provide a very useful guide for the related investigation and application of CBT.

关键词： Ring-opening polymerization Crystallization Cyclic butylene terephthalate.

Scanning photoacoustic imaging of submucosal gastric tumor based on a long focused transducer in phantom and in vitro experiments

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Journal of Innovative Optical Health Sciences 2019年第3期12卷 55-66页

作者： Hua-Qin Wu Hao-Yu Wang Wen-Ming Xie Shu-lian Wu zhi-fang li Xiao-Man Zhang Hui li Key Laboratory of Optoelectronic Science and Technology for Medicine Ministry of Education Fujian Provincial Key Lab of Photonic Technology College of Photonic and Electronic Engineering Fujian Normal University Fuzhou 350007FujianP.R.China

Photoacoustic imaging,which can provide the maximum intensity contrast in tissue depth imaging without ionizing radiation,will be a promising imaging trend for tumor *** this paper,a column diffusionfiber was employed to carry a pulsed laser for irradiating stomach directly through esophagus based on the characteristics of gastric tissue structure.A long focused ultrasonic transducer was placed outside the body to detect photoacoustic signals of gastric *** and in vitro experiments of submucosal gastric tumors were carried out to check the sensitivity of scanning photoacoustic tomography system,including the lateral and longitudinal resolution of the system,sensitivity of different absorption coefficient in imaging,capability of transversal detection,and probability of longitudinal *** results demonstrate that our innovative technique can improve the parameters of *** lateral resolution reaches 2.09 *** a depth of 5.5mm with a longitudinal accuracy of 0.36mm below gastric mucosa of early gastric cancer(EGC)has been *** addition,the optimal absorption coefficient differences among absorbers of system are 3.3-3.9 *** indicate that our photoacoustic imaging(PAI)system,is based on a long focusing transducer,can provide a potential application for detecting submucosal EGC without obvious symptoms.

关键词： Column diffusionfiber long focusing transducer gastric tumor detection scanning photoacoustic tomography phantom experiment

Facile Synthesis of Amidines via Intermolecular Reductive Coupling of Nitriles with Azobenzene Promoted by Samarium Diiodide

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Chinese Chemical Letters 2000年第6期11卷 495-498页

作者： zhi fang li Ping LU Yong Min ZHANG(Department of Chemistry, Zhejiang University (Xixi campus), Hangzhou 310028Laboratory of Organometallic Chemistry, Institute of Organic Chemistry Chinese Academy of Sciences, Shanghai 200032) Zhejiang Univ Dept Chem Hangzhou 310028 Peoples R China Chinese Acad Sci Inst Organ Chem Organomet Chem Lab Shanghai 200032 Peoples R China

The intermolecular reductive coupling of nitrites with azobenzene induced by SmI2 was studied. Amidine derivatives were prepared in good yields under neutral and mild conditions.

关键词： synthesis samarium amidines nitriles azobenzene

Peripheral mechanism of inhibitory effect of centrally administrated histamine on gastric acid secretion

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World Journal of Gastroenterology 1998年第3期4卷 42-44页

作者： ZHANG zhi fang, WANG Zhu li and LU Guang Qi

AIM To study the peripheral mechanism of the inhibitory effect of intra third ventricular administration (icv) of histamine (HA) on gastric acid secretion in rats. METHODS Gastric acid was continuously washed with 37℃ saline by a perfusion pump in male adrenalectomized SD rats. Drugs were injected intravenously (iv) by a syringe pump and their effect on pentagastrin induced (10μg·kg·h, iv) gastric acid secretion was observed. RESULTS The inhibitory effect of HA (1μg, icv) on gastric acid secretion was blocked by subdiaphragmatic vagotomy, and pretreatment with atropine (0 005mg·kg·h, iv). Pretreatment with somatostatin antagonist, cyclo [7 aminoheptanoyl Phe D Trp Lys Thr(Bzl)], ( 2μg - 4μg ·kg· 100min , iv) could also block the inhibitory effect of HA on gastric acid secretion in a dose dependent manner. CONCLUSION The inhibitory effect of centrally administrated HA on gastric acid secretion may be mediated by vagi, acetylcholine M receptor and somatostatin.

关键词： gastric acid/secretion histamine stomach/physiology somatostatin acetylcholine M receptor rats

Preoperative preparation and surgical separation of conjoined pygopagus twins

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Chinese Medical Journal 2010年第13期123卷 1800-1803页

作者： SUN Tian-sheng li Shao-guang ZHANG zhi-cheng li fang GUAN Kai Department of Orthopedic Surgery Beijing Army General Hospital Beijing 100700 China

Conjoined twins are very rare with an estimated ,incidence of about 1 in 200 000 births with a male-female ratio of 1：3 The separation ot conjolned twins presents a challenge to surgeons and also a test for comprehensive efficiency of a hospital. Recently, a rare pair of pygopagus twins were admitted to our hospital and a successful surgical separation was carded out.

关键词： pygopagus conjoined twins preoperative care separation

Percutaneous Nucleoplasty Using Coblation Technique for the Treatment of Chronic Nonspecific Low Back Pain： 5-year Follow-up Results

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Chinese Medical Journal 2015年第14期128卷 1893-1897页

作者： Da-Jiang Ren Xiu-Mei liu Sui-Yong Du Tian-Sheng Sun zhi-Cheng Zhang fang li Department of Orthopedic Surgery Beijing Army General Hospital Dongcheng District Beijing 100700 China

Background： This study evaluated the efficacy of percutaneous nucleoplasty using coblation technique for the treatment of chronic nonspecific low back pain （LBP）, after 5 years of follow-up. Methods： From September 2004 to November 2006, 172 patients underwent percutaneous nucleoplasty for chronic LBP in our department. Forty-one of these patients were followed up for a mean period of 67 months. Nucleoplasty was performed at L3/4 in 1 patient; L4/5 in 25 patients; L5/$1 in 2 patients; L3/4 and L4/5 in 2 patients; L4/5 and L5/$1 in 7 patients; and L3/4, L4/5, and L5/$1 in 4 patients. Patients were assessed preoperatively and at 1 week, 1 year, 3 years, and 5 years postoperatively. Pain was graded using a 10-cm Visual Analogue Scale （VAS） and the percentage reduction in pain score was calculated at each postoperative time point. The Oswestry Disability Index （ODI） was used to assess disability-related to lumbar spine degeneration, and patient satisfaction was assessed using the modified MacNab criteria. Results： There were significant differences among the preoperative, 1-week postoperative, and 3-year postoperative VAS and ODI scores, but not between the 3- and 5-year postoperative scores. There were no significant differences in age, sex, or preoperative symptoms between patients with effective and ineffective treatment, but there were significant differences in the number of levels treated, Pfirrmann grade of intervertebral disc degeneration, and provocative discography findings between these two groups. Excellent or good patient satisfaction was achieved in 87.9% of patients after 1 week, 72.4% after 1 year, 67.7% after 3 years, and 63.4% at the last follow-up. Conclusions： Although previously published short- and medium-term outcomes after percutaneous nucleoplasty appeared to be satisfactory, our long-term follow-up results show a significant decline in patient satisfaction over time. Percutaneous nucleoplasty is a safe and simple technique, with therapeut

关键词： Discogenic Low Back Pain Follow-up Nonspecific Low Back Pain Nucleoplasty Surgical Treatment

A selective optical chemical sensor for the determination of iodine based on fluorescence quenching of liTOE

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Journal of Environmental Science and Engineering 2008年第1期2卷 72-77页

作者： LONG li-ping ZHONG Tong-sheng WANG Jiao-liang YIN zhi-fang li Wang-ying LEI Cun-xi Department of Chemistry ＆ Environmental Engineering Hunan City College Yiyang 413000 China

An optical chemical sensor has been developed for the determination of iodine based on the reversible fluorescence quenching of 2, 2, 7, 7, 12, 12, 17, 17-octamethyl-21, 22, 23, 24-tetraoxaquaterene-li （liTOE） immobilized in a plasticized poly（vinyl chloride）（PVC） membrane. The optimum membrane of the sensor consists of 100 mg of PVC, 200 mg of bis （2-ethytbexyl） sebacate （BOS） and 3.0 mg of liTOE. The maximum response of the optode membrane for iodine is obtained in Tris-HCl buffer solutlon （pH 8.0）. With the optimum conditions described, the proposed sensor responds linearly in the measuring range of 3.90×10^-2 to 3.90×10^-4 mol/L, and has a detection limit of 6.0×10^-8 mol/L. The response time of the sensor is less than I rain. In addition to high reproducibility and reversibility of the fluorescence signal, the sensor also exhibits good selectivity. It is not interfered by some common anions and cations. It is applied for the determination of iodine in table salt samples. The results agree with those obtained by another method.

关键词： a selective optical chemical sensor iodine fluorescence quenching 2, 2, 7, 7, 12, 12, 17, 17-Octamethyl-21, 22, 23, 24-tetraoxaquaterene-li (liTOE) optode membrane

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无模板法聚苯胺纳米管的制备及表征

高分子学报 2014年第7期24卷 938-942页

作者：张玉梅张霞李玲李治芳宁夏医科大学基础医学院银川750004 宁夏医科大学药学院银川750004

以过硫酸铵(APS)为氧化剂,在无模板,无掺杂酸条件下,利用超声辅助合成了聚苯胺纳米管.通过透射电子显微镜、傅里叶红外光谱、紫外-可见光谱、X-射线衍射对产物的形貌、结构和性能进行了表征.研究表明,形成的聚苯胺纳米管内径约为10 nm,... 详细信息

以过硫酸铵(APS)为氧化剂,在无模板,无掺杂酸条件下,利用超声辅助合成了聚苯胺纳米管.通过透射电子显微镜、傅里叶红外光谱、紫外-可见光谱、X-射线衍射对产物的形貌、结构和性能进行了表征.研究表明,形成的聚苯胺纳米管内径约为10 nm,外径约为80 nm,长度约为26μm,且管径均匀.苯胺单体浓度越高,聚合速率越快.但是,聚苯胺的形貌与苯胺单体的浓度无关,而与苯胺和过硫酸铵的摩尔比有关.超声在纳米管的形成中起主要作用,它阻止球状胶束无规则团聚,使得在较高的苯胺浓度下(0.2 mol/L)也可形成纳米管.合成的聚苯胺电导率为5×10-3S·cm-1,结晶度不高.

关键词：聚苯胺纳米管无模板法形貌

The Quest for a stable homocyclic silylene

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The Quest for a stable homocyclic silylene