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NUMERICAL SI MULATION OF STEADY FLOWFOR VISCOELASTIC FLUID IN AN ECCENTRIC ANNULUS WITHINNER ROD MOVING AXIALLY

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Journal of Hydrodynamics 2005年第4期17卷 514-518页

作者： YANG Shu-ren WANG chun-sheng CUI Hai-qing zhang chun-liang Department of Petroleum Engineering Daqing Petroleum Institute Daqing 163318 China

The governing equation about steady flow of viscoelastic fluids in an eccentric annulus with inner rod moving axially is established by using common conversion Maxwell constitutive model. The numerical solutions of the flow are obtained by control volume and ADI methods. The influence of the eccentricity, velocity of inner rod and elasticity of fluid to the velocity distribution, flow rate and radial force on the inner rod is obtained, and the reason for the severe eccentric wear of the sucker rod of polymer flood well is analyzed.

关键词： viscoelastic fluid eccentric annulus velocity distribution radial force eccentric wear

Synthesis and characterization of star-comb styrene/butadiene copolymer

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Chinese Chemical Letters 2010年第11期21卷 1370-1373页

作者： qing Min zhang Chuang Chen Hong Xia zhang chun qing zhang Yang Li Xi Gao Jian State Key Laboratory of Fine Chemicals Department of Polymer Science and Engineering School of Chemical Engineering Dalian University of Technology Dalian 116012 China Liaoning Province Key Laboratory of Polymer Science and Engineering Dalian 116012 China

A novel star-comb styrene/butadiene copolymer（SC-SBC） was synthesized by anionic polymerization and grafting reaction with epoxidized star liquid polybutadiene（ESPB） as coupling *** overall shape of the star-comb macromolecules can be altered by changing the molecular weight and number of the side *** molecular parameters and mechanical properties of the SC-SBC resins were *** notched izod impact strength of the SC-SBC resins are excellent and reach as high as to 239 J/m.

关键词： Anionic polymerization Epoxidation Grafting reaction Star-comb copolymer Side chain

Assessing acceptance in mindfulness with direct-worded items:The development and initial validation of the Athlete Mindfulness Questionnaire

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Journal of Sport and Health Science 2017年第3期6卷 311-320页

作者： chun-qing zhang Pak-Kwong chung Gangyan Si Department of Physical Education Hong Kong Baptist University Department of Health and Physical Education Hong Kong Institute of Education

Purpose:The purpose of the current study was to develop and validate a sport-specific mindfulness measure,the Athlete Mindfulness Questionnaire(AMQ),through 5 related studies using 4 separate samples of Chinese *** AMQ is a 3-factor measure designed to assess mindfulness that reflects present-moment attention,awareness,and acceptance in a sport ***:In Study 1,an initial pool of items was generated based on previous literature,existing mindfulness scales,as well as interviews with and feedback from the athletes,coaches,and mindfulness *** support for the 3-factor structure of the AMQ was established via exploratory factor analysis in Study 2,and cross-validated through confirmatory factor analysis in Studies 3 and *** Study 5,a modified 3-factor AMQ with direct-worded acceptance items was examined in a fourth independent ***:Convergent and concurrent validities of the acceptance subscale failed to be established in Studies 3 and 4 which may be due to the inattention and confusion of the athletes whilst interpreting the reverse-worded items.A modified 16-item AMQ in Study 5 displayed satisfactory model fit and acceptable internal *** importantly,convergent and concurrent validities of the 16-item AMQ were ***3 subscales showed significant positive associations with mindfulness,flow,well-being,and positive affect and significant negative associations with experiential avoidance,burnout,and negative ***:The AMQ is a psychometrically sound measure of mindfulness in a sport *** importance of using direct-worded acceptance items is discussed.

关键词： Athlete Mindfulness Reliability Scale Sport Validity

Synthesis and Characterization of Ion-exchange Sulfonated Poly (ether sulfone)

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Chinese Chemical Letters 2006年第4期17卷 447-448页

作者： Fan Xiu MENG chun qing zhang Lian LIU Yuan Yuan zhang Department of Polymer Materials Science School of Chemical Engineer Dalian University of Technology Dalian 116012

N,N＇-Bis（3-hydroxyphenyl）-1,8,4,5-naphthalenetetracarboxylic bisimide was prepared from the reaction of 1,8,4,5-naphthalenetetrcarboxylic acid dianhydride and 2-aminophenol in N, N-dimethylformamide. Polymerization of this bisimide with 4,4＇-difluorodiphenylsulfone and disodium 3,3＇-disulfonate4,4＇-difluorodiphenylsulfone gave ion-exchange sulfonated poly（ether sulfone）. The structure of the title compound was characterized with H-NMR and its polymer was characterized with FT-IR.

关键词： Bisimide ion-exchange polymer sulfonated poly(ether sulfone).

Percutaneous transhepatic intraportal biopsy using gastroscope biopsy forceps for diagnosis of a pancreatic neuroendocrine neoplasm:A case report

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World Journal of Gastroenterology 2023年第7期29卷 1235-1242页

作者： Guang-Chuan Wang Guang-Jun Huang chun-qing zhang Qian Ding Department of Gastroenterology Shandong Provincial Hospital Affiliated to Shandong First Medical UniversityJinan 250021Shandong ProvinceChina

BACKGROUND Pancreatic neuroendocrine neoplasms(PNENs)are a rare group of neoplasms originating from the islets of the *** vein tumor thrombosis has been reported in 33%of patients with *** the histopathological diagnosis of PNENs is usually based on percutaneous biopsy or endoscopic ultrasound-guided fine-needle aspiration(EUS-FNA),these approaches may be impeded by gastric varices,poor access windows,or anatomically contiguous critical *** a pathological diagnosis using a gastroscope biopsy forceps via percutaneous transhepatic intravascular pathway is an innovative method that has rarely been *** SUMMARY A 72-year-old man was referred to our hospital for abdominal pain and *** contrast-enhanced magnetic resonance imaging revealed a wellenhanced tumor(size:2.4 cm×1.2 cm×1.2 cm)in the pancreatic tail with portal vein *** pathological diagnosis via EUS-FNA was not possible because of diffuse gastric *** performed a percutaneous transportal biopsy of the portal vein tumor thrombus using a gastroscope biopsy *** examination revealed a pancreatic neuroendocrine neoplasm(G2)with somatostatin receptors 2(+),allowing systemic *** Intravascular biopsy using gastroscope biopsy forceps appears to be a safe and effective method for obtaining a histopathological *** welldesigned clinic trials are required to obtain more definitive evidence,this procedure may help improve the diagnosis of portal vein thrombosis and related diseases.

关键词： Percutaneous transhepatic intravascular biopsy Portal vein tumor thrombosis Gastroscope biopsy forceps Pancreatic neuroendocrine neoplasms Case report

Transjugular intrahepatic portosystemic shunt is effective in patients with chronic portal vein thrombosis and variceal bleeding

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Hepatobiliary & Pancreatic Diseases International 2021年第2期20卷 128-136页

作者： Xiao-Yan Sun Guang-Chuan Wang Jing Wang Guang-Jun Huang chun-qing zhang Department of Gastroenterology Shandong Provincial Hospital Affiliated to Shandong First Medical UniversityJinan 250021China Department of Infectious Diseases Shandong Provincial Hospital Affiliated to Shandong First Medical UniversityJinan 250021China

Background:Studies about treatment of patients with chronic portal vein thrombosis(CPVT)are still limited,especially in different types of *** study aimed to evaluate the effect of transjugular intrahepatic portosystemic shunt(TIPS)in all types of CPVT with variceal ***:Patients with CPVT who received TIPS treatment between January 2011 and June 2019 were divided into four types according to the extent of *** patients had a history of variceal *** characteristics and clinical parameters were collected and *** on procedure success rate,variation in portal vein pressure,rebleeding,hepatic encephalopathy(HE),stent stenosis,and overall mortality were ***:A total of 189 patients were included in this study(39 in type 1,84 in type 2,48 in type 3,18 in type 4).The TIPS procedure success rate was 86.2%.The success rate was significantly different among the four types(89.7%vs.88.1%vs.83.3%vs.77.8%,P=0.001).In the TIPS success group,portal vein pressure was significantly reduced from 27.15±6.59 to 19.74±6.73 mm Hg after the procedure(P<0.001)and the rebleeding rate was significantly lower than that of the fail group(14.7%vs.30.8%,P=0.017).In addition,there were no significant differences in HE rate(30.7%vs.26.9%,P=0.912)or overall mortality(12.9%vs.19.2%,P=0.403)between the TIPS success group and the fail *** the TIPS success group,we found that the occurrence of HE was significantly different(P=0.020)among the four types,while there were no significant differences in rebleeding rate(P=0.669),stent stenosis rate(P=0.056),or overall mortality(P=0.690).Conclusions:TIPS was safe and effective in decreasing portal vein pressure and rebleeding rate in patients with CPVT.

关键词： Chronic portal vein thrombosis Transjugular intrahepatic portosystemic shunt Variceal bleeding Hepatic encephalopathy

Identification of in vitro and in vivo metabolites of 12β-hydroxylveratroylzygadenine associated with neurotoxicity by using HPLC–MS/MS

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Chinese Chemical Letters 2014年第8期25卷 1107-1111页

作者： Yue Cong Jing-Gong Guo Zhi Tang qing-chun zhang Zong-Wei Cai Institute of Pharmacy Pharmaceutical College Henan University State Key Laboratory of Environmental and Biological Analysis Department of Chemistry Hong Kong Baptist University The Key Laboratory of Plant Stress Biology Henan University

Metabolism study was carried out on 12b-hydroxylveratroylzygadenine（VOG） that is a cevine-type alkaloid existing in Veratrum nigrum L. and a neurotoxic component. In order to better understand the potential mechanism of neurotoxicity of VOG, this study measured VOG-induced DNA damage in the cerebellum and cerebral cortex of mice after 7 days repetitive oral dose by using single-cell gel electrophoresis（Comet assay）. High performance liquid chromatography-tandem mass spectrometry（LC–MS/MS） was developed and applied to separate and identify in vitro and in vivo metabolites of VOG for investing the possible relationship of metabolism and neurotoxicity. In vitro experiment was carried out using rat liver microsomes, while the in vivo study was conducted on rats. The obtained results indicated that VOG might cause DNA damage in cerebellum and cerebral cortex of mice in a dosedependent manner. Hydrolysis of ester bond and O-demethylation were proposed to be the main in vivo metabolic pathways of VOG, while the major in vitro metabolic pathways were proposed as methyl oxidation to aldehyde, dehydrogenation, hydrolysis of ester bond, hydrolysis of ester bond together with acetylation, and methoxylation. O-Demethylation reaction was likely to be associated with reactive oxygen species production, leading to the DNA damage.

关键词： 12β-Hydroxylveratroylzygadenine Metabolites O-Demethylation LC-MS

Unique polysulfide reaction on VO_(2) for restraining shuttle effect in soft-packaged Li-S pouch cells

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Rare Metals 2024年第6期43卷 2842-2850页

作者： Ruo-Xuan Yang qing-chun zhang Jing-Sheng Cai Xuan Cao Qin Yang Ying-Ze Song Wei zhang State Key Laboratory of Environment-Friendly Energy Materials Tianfu Institute of Research and InnovationSchool of Materials and ChemistrySouthwest University of Science and TechnologyMianyang 621010China School of Materials Engineering Changshu Institute of TechnologyChangshu 215500China Chongqing Institute of Green and Intelligent Technology Chinese Academy of SciencesChongqing 400714China

The shuttle phenomenon and retarded conversion kinetics of lithium poly sulfides(LiPSs)are relatively severe in lithium-sulfur(Li-S)pouch *** to their redox potential in the sulfur working window,VO_(2)nanobelts show ... 详细信息

关键词： mechanism sulfide lithium

Risk factors for early rebleeding and mortality in acute variceal hemorrhage

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World Journal of Gastroenterology 2014年第47期20卷 17941-17948页

作者： Jing-Run Zhao Guang-Chuan Wang Jin-Hua Hu chun-qing zhang Department of Gastroenterology Shandong Provincial Hospital Affiliated to Shandong University Department of Gastroenterology Liaocheng People’s Hospital

AIM: To investigate the risk factors for 6-wk rebleeding and mortality in acute variceal hemorrhage (AVH) patients treated by percutaneous transhepatic variceal embolization (PTVE).

关键词： Acute variceal hemorrhage Percutaneous transhepatic variceal embolization Hepatic vein pressure gradient