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Synthesis and Properties of Hydroxytelechelic Polyisobutylenes by End Capping with tert-Butyl-dimethyl-(4-methyl-pent-4-enyloxy)-silane

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Chinese Journal of Polymer Science 2019年第9期37卷 936-942页

作者： Jing li Kang-Da Wu Huang Shan Jing-Han Zhang Ming Zhao Guang-Bi Gong wen-li guo Yi-Bo Wu College of Materials Science & Engineering Beijing Institute of Petrochemical Technology Beijing 102617 China Lanzhou Petrochemical Research Center Petrochina Lanzhou 730060 China Beijing Key Laboratory of Specialty Elastomer Composite Materials Beijing Institute of Petrochemical Technology Beijing 102617 China

The low-activity cationic monomer tert-butyl-dimethyl-(4-methyl-pent-4-enyloxy)-silane was synthesized by Grignard reaction and hydroxyl-protection reaction. living polyisobutylene chains were initially synthesized by controlled cationic polymerization and then capped with tert-butyl-dimethyl-(4-methyl-pent-4-enyloxy)-silane. The hydrolysis of these polyisobutylenes end capped with tert-butyl-dimethyl-(4-methyl-pent-4-enyloxy)-silane gave rise to hydroxytelechelic polyisobutylene. NMR analysis confirmed that the hydrolysis was complete. Results also showed that a low polymerization temperature favored the participation of tert-butyl-dimethyl-(4- methyl-pent-4?enyloxy)-silane in the end-capping reaction. Moreover, polyisobutylene-based polyurethane exhibited greater acid resistance than commercial polyurethane.

关键词： Carbocationic polymerization Polyisobutylene Hydrolysis Polyisobutylene-based polyurethane

linear dipole behavior of single quantum dots encased in metal oxide semiconductor nanoparticles films

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Frontiers of physics 2019年第2期14卷 97-104页

作者： guo-Feng Zhang Yong-Gang Peng Hai-Qing Xie Bin li Zhi-Jie li Chang-Gang Yang wen-li guo Cheng-Bing Qin Rui-Yun Chen Yan Gao Yu-Jun Zheng lian-Tuan Xiao Suo-Tang Jia State Key Laboratory of Quantum Optics and Quantum Optics Devices Institute of Laser SpectroscopyShanxi UniversityTaiyuan 030006China School of Physics Shandong UniversityJinan 250100China Department of Physics Taiyuan Normal UniversityJinzhong 030619China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China

Understanding of charge/energy exchange processes and interfacial interactions that occur between quantum dots (QDs) and the metal oxides is of critical importance to these QD-based optoelectronic devices. This work reports on linear dipole behavior of single near-infrared emitting CdSeTe/ZnS core/shell QDs which are encased in indium tin oxide (ITO) semiconductor lianoparticles films. A strong polarization anisotropy in photohiminescence emission is observed by defocused wide-field imaging and polarization measuremen11echniques, and the average polarization degree is up to 0.45. A possible mechanism for the observation is presented in which the electrons, locating at single QD surface from ITO by electron transfer due to the equilibration of the Fermi levels, result in a significant Stark distortion of the QD electron/hole wavefunctions. The Stark distortion results in the linear polarization property of the single QDs. The investigation of linear dipole behavior for single QDs encased in ITO films would be helpful for further improving QD-based device performance.

关键词： single quantum dots linear dipole behavior electron transfer polarization property metal oxide nanoparticles

Application of Microwave Heating Technique to Esterification

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Chemical Research in Chinese Universities 1992年第4期8卷 465-467页

作者： liU Fu-an, XU wen-guo and li Yao-xian (Department of Chemistry, Jilin University, Changchun, 130023)

Introduction Although the application of microwave technique has been reported as a new type of energy source chemically, it is only in recent years that this technique has been used as the energy source for organic synthesis. In 1986, R. Gedye, et al., published the report of the benzoate synthesis from the respective reactions between benzene carboxylic acid and methanol, propanol or butanol under microwave heating and the catalysis of H;SO;.

关键词： Microwave heating Esterification

Magnetic Resonance Three-dimensional Cube Technique in the Measurement of Piglet Femoral Anteversion

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Chinese Medical Journal 2016年第13期129卷 1584-1591页

作者： Dong-Mei Sun Shi-Nong Pan En-Bo Wang li-Qiang Zheng wen-li guo Xi-Hu Fu Department of Radiology Shengjing Hospital of China Medical University Shenyang Liaoning 110004 China Department of Pediatric Orthopedics Shengjing Hospital of China Medical University Shenyang Liaoning 110004 China Department of Clinical Epidemiology Shengjing Hospital of China Medical University Shenyang Liaoning 110004 China

Background： The accurate measurement of the femoral anteversion （FA） angle is always a topic of much debate in the orthopedic surgery and radiology research. We aimed to explore a new FA measurement method to acquire accurate results without radiation damage using piglet model. Methods： A total of thirty piglets were assigned to two groups based on the age. Bilateral femora were imaged with 3.0-T magnetic resonance （MR） and 64-slice computed tomography （CT） examinations on all piglets. FA was measured on MR-three-dimensional （3D） postprocessing software with a four-step method： initial validation of the femoral condylar axis, validation of the condylar plane, validation of the femoral neck axis, and line-plane angle measurement of FA. After MR and CT examinations, all piglets were sacrificed and their degree of FA was measured using their excised, dried femora. MR, CT, and dried-femur measurement results were analyzed statistically; M R and CT measurements were compared for accuracy against each other and against the gold standard dried femur measurement. Results： In both groups, the mean FA value measured by MR was lower than that measured by CT. A statistically significant difference was observed between CT- and dried-femur measurements but not between MR- and dried-femur measurements. A higher correlation （0.783 vs. 0.408） and a higher consistency （0.863 vs. 0.578） with dried-femur measurement results were seen for MR measurements than CT measurements in the 1 -week age group. However, in the 8-week age group, similar correlations （0.707 vs. 0.669） and consistencies （0.864 vs. 0.82 l ） were observed. Conclusions： Noninvasive MR-3D-Cube reconstruction was able to accurately measure FA in piglets. Particularly in the 1-week age group with a larger proportion of cartilaginous structures, the correlation and consistency between MR- and dried-femur measurement results were higher than those between CT- and dried-femur measurements, suggesting that MR may be a new usef

关键词： Femoral Anteversion Hip Magnetic Resonance Imaging Piglet Three-dimensional Fast Spin Echo Cube

PARALLEL IMPLEMENTATION AND OPTIMIZATION OF THE SEBVHOS ALGORITHM

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Journal of Electronics(China) 2011年第3期28卷 277-283页

作者： li wen guo li Yuan Hongxing Wei Yifang Guan Hua Deptartmen of Electronic Science and Technology University of Science and Technology of China Hefei 230027 China

In this paper, a parallel Surface Extraction from Binary Volumes with Higher-Order Smoothness (SEBVHOS) algorithm is proposed to accelerate the SEBVHOS execution. The original SEBVHOS algorithm is parallelized first, and then several performance optimization techniques which are loop optimization, cache optimization, false sharing optimization, synchronization overhead op-timization, and thread affinity optimization, are used to improve the implementation's performance on multi-core systems. The performance of the parallel SEBVHOS algorithm is analyzed on a dual-core system. The experimental results show that the parallel SEBVHOS algorithm achieves an average of 1.86x speedup. More importantly, our method does not come with additional aliasing artifacts, com-paring to the original SEBVHOS algorithm.

关键词： Multi-core Parallel algorithm Performance optimization 3D reconstruction

Double-balloon enteroscopy reliably directs surgical intervention for patients with small intestinal bleeding

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World Journal of Gastroenterology 2008年第12期14卷 1936-1940页

作者： Mou-Bin lin Lu Yin Jian-wen li Wei-guo Hu Qian-Jian Qian Department of Surgery Ruijin Hospital Shanghai 200025China

AIM: To evaluate preoperative double-balloon enteroscopy for determining bleeding lesions of small intestine, thus directing selective surgical intervention. METHODS: We retrospectively reviewed 56 patients who underwent double-balloon enteroscopy to localize intestinal bleeding prior to surgical intervention, and compared enteroscopic findings with those of intraoperation to determine the accuracy of enteroscopy in identifying and localizing the sites of small intestinal bleeding. RESULTS: Double-balloon enteroscopy was performed in all 56 patients in a 30-mo period. A possible site of blood loss was identified in 54 (96%) patients. Enteroscopy provided accurate localization of the bleeding in 53 (95%) of 56 patients, but failed to disclose the cause of bleeding in 4 (7%). There was one case with negative intraoperative finding (2%). Resection of the affected bowel was carried out except one patient who experienced rebleeding after operation. Gastrointestinal stromal tumor (GIST) was most frequently diagnosed (55%). CONCLUSION: Double-balloon enteroscopy is a safe, reliable modality for determining bleeding lesion of small intestine. This technique can be used to direct selective surgical intervention.

关键词： Double-balloon enteroscopy Small intestinebleeding Surgery

基于小波变换和盲信号分离的多通道肌电信号处理方法

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电子学报 2009年第4期37卷 823-827页

作者：罗志增李文国杭州电子科技大学机器人研究所浙江杭州310018

为了消除多通道表面肌电信号(SEMG)采集时形成的混叠现象,提出一种新的SEMG处理方法.该方法将小波变换和独立分量分析(ICA)结合,利用小波变换的去噪作用,滤除混合在原始SEMG中的部分噪声后作为ICA的输入信号,采用Infomax算法对输入信号... 详细信息

为了消除多通道表面肌电信号(SEMG)采集时形成的混叠现象,提出一种新的SEMG处理方法.该方法将小波变换和独立分量分析(ICA)结合,利用小波变换的去噪作用,滤除混合在原始SEMG中的部分噪声后作为ICA的输入信号,采用Infomax算法对输入信号实施盲分离,并引入相关系数验证ICA分量与源信号的一致性.实验结果表明,该方法用于多通道SEMG的盲分离是很有效的.

关键词：表面肌电信号独立分量分析小波变换 Infomax算法互相关系数

XAF1 as a prognostic biomarker and therapeutic target in squamous cell lung cancer

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Chinese Medical Journal 2011年第20期124卷 3238-3243页

作者： CHEN Yong-bing SHU Jian YANG wen-tao SHI li guo Xu-feng WANG Fei-ge QIAN Yong-yue Department of Cardiothoracic Surgery Second Affiliated HospitalSoochow University Suzhou Jiangsu 215004 China

Background X-linked inhibitor of apoptosis （XlAP）-associated factor 1 （XAF1） is a new tumor suppressor. Low expression of XAF1 is associated with poor prognosis of human cancers. However, the effect of XAF1 on lung cancer remains unknown. In this study, we investigated the expression of XAF1 and its role in squamous cell lung cancer. Methods Cancer tissues, cancer adjacent tissues and normal lung tissues were collected from 51 cases of squamous cell lung cancer. The expression of XAF1 mRNA was determined by reverse transcription-polymerase chain reaction （RT-PCR）. The expression of XAF1 protein was determined by Western blotting and immunohistochemical staining. Ad5/F35-XAF1 virus was generated. Cell proliferation and apoptosis were measured by 3-（4, 5-dimethylthiazol-2-yl）-2, 5-diphenyltetrazolium bromide （MTT） method and flow cytometry （FACS）, respectively. Results The levels of XAF1 protein and mRNA in cancer tissues were significantly lower than those in cancer adjacent and normal lung tissues （P 〈0.05）. The low expression of XAF1 was associated with tumor grade, disease stage, differentiation status and lymph node metastasis in squamous cell lung cancer patients. The restoration of XAF1 expression mediated by Ad5/F35-XAF1 virus significantly inhibited cell proliferation and induced apoptosis in a dose- and time-dependent manner. Conclusion XAF1 is a valuable prognostic marker in squamous cell lung cancer and may be a potential candidate gene for lung cancer therapy.

关键词： XAF1 human lung cancer cell lines cell proliferation apoptosis prognosis, biomarker

Uniportal versus biportal video-assisted thoracoscopic sympathectomy for palmar hyperhidrosis

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Chinese Medical Journal 2009年第13期122卷 1525-1528页

作者： CHEN Yong-bing YE Wu YANG wen-tao SHI li guo Xu-feng XU Zhong-hua QIAN Yong-yue Department of Cardiothoracic Surgery the Second Affiliated Hospital Soochow University Suzhou Jiangsu 215004 China

Background Video-assisted thoracoscopic sympathectomy had replaced open surgery. The aim of this study was to compare the outcomes of using a single port and two ports to perform video-assisted thoracoscopic sympathectomy for palmar hyperhidrosis. Methods Between April 2006 and February 2008, 20 cases underwent video-assisted thoracoscopic sympathectomy through one port （uniportal group） and 25 cases through two ports （biportal group）. The variables including the operating time, hospital stay, pain scores, postoperative complications, incidence of symptom recurrence and patient satisfaction were compared. The mean postoperative follow-up period was 11.5 months （range, 3-25 months）. Results The hands of all patients were warm and dry after operation. No conversion to open surgery was necessary, and no operative mortality was recorded in either group. The mean inpatient pain scores were significantly higher in the biportal group （1.2±0.6） than that in the uniportal group （0.8±0.5, P=0.025）. For the first three weeks after operation, four out of 20 （20%） patients in the uniportal group constantly suffered from mild or moderate residual pain while eight out of 25 （32%） cases in the biportal group （P=0.366）. Among them, two cases in the uniportal group and five cases in the biportal group need to take analgesics. Our mean operative time （bilateral sympathectomy） in the uniportal group （（39.5±10.0） minutes） was shorter than that in biportal group （（49.7±10.6） minutes, P=0.02）. There were no significant differences between two groups in terms of the mean hospital stay, compensatory sweating, and patient satisfaction. Two patients in the biportal group and three in the uniportal group experienced a unilateral pneumothorax. None of them required chest drainage. No patient experienced Homer＇s syndrome, and no recurrent symptoms were observed in either groups Conclusions Both uniportal and biportal video-assisted thoracoscopic sympathectomy are effective, safe, and minimally i

关键词： uniportal hyperhidrosis thoracic surgery, video-assisted sympathectomy