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The Magnetic Field Effect on the Polymerization of Styrene in Supercritical Carbon Dioxide

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Chinese Chemical Letters 2001年第5期12卷 465-466页

作者： Jun liu Hong Ping LI zhi min liu Bu Xing HAN Hai Ke YAN Center for Molecular Science Institute of ChemistryChinese Academy of SciencesBeijing 100080

Styrene was polymerized in supercritical （sc） CO2 with benzoyl peroxide （BPO） as initiator. It was found that the polymerization was accelerated by the external magnetic field.

关键词： Magnetic field effect polymerization styrene supercritical carbon dioxide

Preparation of Semi-interpenetrating Polymer Network of Silicon Rubber and Poly(methyl methylacrylate) Using Supercritical CO_2

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Chinese Chemical Letters 2002年第7期13卷 683-684页

作者： zhi min liu Jia Qiu WANG Guan Ying YANG Bu Xing HAN Center for molecular sciences Institute of ChemistryChinese Academy of SciencesBeijing 100080

The heterogeneous free-radical polymerization of methyl methylacrylate (MMA) and divinylbenzene (DVB) as cross-linker within supercritical carbon dioxide-swollen silicon rubber (SR) has been studied as an approach to preparing semi-interpenetrating polymer network (semi-IPN) of SR and poly(methyl methylacrylate) (PMMA). The SR/PMMA semi-IPNs were characterized by scanning electron microscopy (SEM) and dynamic mechanical analyzer (DMA).

关键词： Supercritical CO2 interpenetrating polymer network silicon rubber poly(methyl methylacrylate) polymerization.

Isotropic or anisotropic screening in black phosphorous: Can doping tip the balance?

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Frontiers of physics 2020年第5期15卷 103-109页

作者： zhi-min liu Ye Yang Yue Shao Zheng Qin-Jun Chen Ye-Xin Feng Hunan Provincial Key Laboratory of Low-Dimensional Structural Physics&Devices School of Physics and ElectronicsHunan UniversityChangsha410082China

Black phosphorus(BP),a layered van der Waals(vdW)crystal,has umique in-plane band anisotropy and many resulting anisotropy properties such as the ffective mass,electron mobility,optical absorp-tion,thermal conductivity and plasmonie ***,whether anisotropic or isotropic charge screening exist in BP remains a controversial *** on first-principles calculations,we study the screening properties in both of single-layer and bulk BP,especially conoerning the role of *** charge doping,the single-layer and bulk phase BP show slight anisotropic *** and hole doping can increase the charge screening of BP and significantly change the relative static dielectric tensor elements along two different in-plane *** further study the charge density change induced by potassium(K)adatom near the BP surface,under different levels of charge *** calculated two-dimensional(2D)charge redlistribution patterns also confirm that doping can greatly ffect the screening feature and tip the balance between isotropic and anisotropice *** corroborate that screening in BP exhibits slight intrinsic anisotropy and doping has significant influenoe on its screening property.

关键词： first-principles calculation charge screening black phosphorus dielectric function doping

Oxidative damage in the kidney and brain of mice induced by different nano-materials

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Frontiers in Biology 2015年第1期10卷 91-96页

作者： Shuai SHANG Shang-Yue YANG zhi-min liu Xu YANG College of Life Sciences Central China Normal University Wuhan 430079 China

With the rapid development of nanotechnology, nanomaterials have been used in numerous fields. However, these nanomaterials could also result in risk for human and environmental health. To make a comparison of the health effects of three different kinds of nanomaterials, 28 male BALB/c mice were randomly divided into four groups. Three experimental groups were exposed to different kinds of nanomaterials including graphene, graphene oxide and single wall carbon nanotubes （SWCNTs） by intraperitoneal injection while the control group received a saline injection. The exposure dose of experimental groups was 4mg/kg. After seven days, sections of mice kidney were taken, the organ coefficient of both kidney and brain was counted, and the reactive oxygen species （ROS） level, glutathione （GSH） and malondialdehyde （MDA） content was measured. Our results showed that in the experimental groups, the organ coefficient and GSH content in mice kidneys and brains decreased, whereas the ROS level and MDA content increased, when compared with the control. The graphene oxide group was statistically significant （p 〈 0.05）, while the SWCNTs group had extremely significant difference （p〈0.01）. Morphological changes in the kidney were also seen in the experimental groups. These results demonstrate that oxidative damage to mice kidneys and brains induced by SWCNTs and graphene oxide is more severe than graphene. The degree of damage caused by these three typical nanomaterials is different, probably due to several parameters including particle size, surface character, and shape.

关键词： graphene graphene oxide single wall carbon nanotubes oxidative damage

Endoscopic retrograde cholangiopancreatography for diagnosing and treating pediatric biliary and pancreatic diseases

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World Journal of Gastrointestinal Surgery 2023年第10期15卷 2272-2279页

作者： Xiu-min Qin Fei-Hong Yu Chuan-Kai Lv zhi-min liu Jie Wu Department of Gastroenterology Beijing Children’s HospitalCapital Medical UniversityNational Center for Children’s HealthBeijing 100045China Department of Ultrasound Beijing Children’s HospitalCapital Medical UniversityNational Center for Children’s HealthBeijing 100045China Department of Radiology Beijing Children’s HospitalCapital Medical UniversityNational Center for Children’s HealthBeijing 100045China

BACKGROUND This study evaluated the safety and effectiveness of endoscopic retrograde cholangiopancreatography(ERCP)in pediatric patients with biliary and pancreatic diseases.A retrospective analysis was conducted on 57 ERCP procedures performed in 41 children,primarily for treating pancreatic *** overall success rate was 91.2%,with no major complications ***-ERCP pancreatitis(PEP)occurred in 8.8%of ***-up examinations over one year showed no recurrence of biliary or pancreatic ***,endoscopic treatment led to a significant increase in body mass index(BMI).These findings demonstrate the valuable role of ERCP in managing such *** To evaluate the safety and efficacy of ERCP for the management of biliary and pancreatic diseases in pediatric *** We conducted a retrospective analysis of data from children aged 1-18 years who underwent ERCP for biliary and pancreatic diseases at Beijing Children’s Hospital between January 2021 and December *** collected data included procedure time,endoscopic treatment,success rate,and postoperative *** Forty-one children underwent 57 ERCP procedures,including 14 with biliary duct disease and 27 with pancreatic *** mean age of the patients was 7.48±3.48 *** duct-related treatments were performed 18 times,and pancreatic disease treatments were performed 39 *** was primarily used to treat pediatric pancreatic diseases[68.4%(39/57)of the procedures].The overall success rate was 91.2%(52/57 patients).PEP was noted in five patients(8.8%,5/57),and no instances of bleeding,perforation,or cholangitis were *** patients were followed up for over one year,and no recurrence of biliary or pancreatic diseases was ***,BMI significantly increased after endoscopic treatment compared to that before treatment(P=0.001).CONCLUSION The high success rate and lack of major complications support the valuable role of ERCP in the

关键词： Pediatric Endoscopic retrograde cholangiopancreatography Choledocholithiasis Chronic pancreatitis Pancreatic ducts Postoperative complications

Effect of Ultrasonication on Optical Properties and Electronic States of Conjugated Polymer MEH-PPV

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Chemical Research in Chinese Universities 2008年第5期24卷 653-657页

作者： WU Meng YANG Gui-zhong WANG Meng WANG Wei-zhi WANG min liu Tian-xi Key Laboratory of Molecular Engineering of Polymers of ministry of Education Department of Macromoleeular Science Laboratory of Advanced Materials Fudan University Shanghai 200433 P. R. China

Poly[2-methoxy-5-（2＇-ethyl-hexyloxy）-1,4-phenylene vinylene]（MEH-PPV）solutions with different concen-trations were prepared in chloroform for different ultrasonication *** ultraviolet absorption and photoluminescence（PL）spectra of the MEH-PPV solutions were measured,and the electronic states of the polymer chains under different experimental conditions were *** results showed that the effects of ultrasonication on the dilute and concentrated solutions were *** ultrasonication,the intensity of the absorption peak at 280 nm significantly decreased,relative to the absorption peak at 500 nm for both dilute and concentrated solutions,indicating that the proportion of the two excited states in the polymer chains had *** dilute MEH-PPV solutions,the blue-shifted absorption（at about 500 nm）and PL spectra show that ultrasonication also led to polymer chain degradation and thus shortened the effective conjugation *** concentrated solutions,however,the peak positions of the absorption spectra remained *** addition,the effects of the solution temperatures on the optical spectra for the MEH-PPV solutions were also discussed.

关键词： MEH-PPV Optical property Electronic state Ultrasonication

Stapled transperineal repair for low-and mid-level rectovaginal fistulas:A 5-year experience and comparison with sutured repair

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World Journal of Gastroenterology 2021年第14期27卷 1451-1464页

作者： Qian Zhou zhi-min liu Hua-Xian Chen Dong-Lin Ren Hong-Cheng Lin Department of Coloproctology The Sixth Affiliated Hospital of Sun Yat-sen UniversityGuangzhou 510655Guangdong ProvinceChina Guangdong Provincial Key Laboratory of Colorectal and Pelvic Floor Diseases The Sixth Affiliated Hospital of Sun Yat-sen UniversityGuangzhou 510655Guangdong ProvinceChina Guangdong Institute of Gastroenterology The Sixth Affiliated Hospital of Sun Yat-sen UniversityGuangzhou 510655Guangdong ProvinceChina

BACKGROUND Currently,rectovaginal fistula(RVF)continues to be a surgical challenge worldwide,with a relatively low healing *** intermittent suture and poor suture materials may be the main reasons for *** To evaluate the efficacy and safety of stapled transperineal repair in treating *** This was a retrospective cohort study conducted in the Coloproctology Department of The Sixth Affiliated Hospital of Sun Yat-sen University(Guangzhou,China).Adult patients presenting with RVF who were surgically managed by perineal repair between May 2015 and May 2020 were *** the 82 total patients,37 underwent repair with direct suturing and 45 underwent repair with *** demographic data,Wexner faecal incontinence score,and operative data were *** rate and associated risk factors were *** The direct suture and stapled repair groups showed similar clinical characteristics for aetiology,surgical history,fistula features,and perioperative Wexner *** stapled repair group did not show superior results over the suture repair group in regard to operative time,blood loss,and hospital ***,the stapled repair group showed better postoperative Wexner score(1.04±1.89 vs 2.73±3.75,P=0.021),less intercourse pain(1/45 vs 17/37,P=0.045),and lower recurrence rate(6/45 vs 17/37,P=0.001).There was no protective effect from previous repair history,smaller diameter of fistula(10)were risk factors for fistula ***,stapled repair gave better efficacy in treating complex RVFs(i.e.,multiple transperineal repair history,mid-level fistula position,and poor control of defecation).CONCLUSION Stapled transperineal repair is advantageous for management of RVF,providing a high primary healing rate and low recurrence rate.

关键词： Rectovaginal fistula Surgical repair Transperineal approach Stapled technique Recurrence

The Oxidation of Cyclohexene with Polymer Supported Co(II) in Supercritical Carbon Dioxide

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Chinese Chemical Letters 2002年第12期13卷 1162-1163页

作者： Jun liu Rui ZHANG Liang GAO Tao JIANG zhi min liu Jun HE Bu Xing HAN Guan Ying YANG Center for Molecular Science Institute of ChemistryChinese Academy of SciencesBeijing 100080

The cyclohexene 1 was oxidized with polymer-supported 2.2-bipyridine cobalt(II) complex in the presence of CO2. The conversion and selectivity was sensitive to the pressure of CO2.

关键词： Oxidation cyclohexene polymer-supported carbon dioxide.

One-layer pancreaticojejunostomy for prevention of pancreatic fistulae

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Hepatobiliary & Pancreatic Diseases International 2004年第1期3卷 140-143页

作者： zhi-min liu Wei-Jian Yang Yan-Chang Feng Department of General Surgery Zibo Municipal Central Hospital Binzhou Medical College Zibo 255036 China. liuzhimin77@***

BACKGROUND: Anastomotic leakage at the pancreaticojejunostomy remains a common and dreaded complication after pancreaticoduodenectomy. This study was to introduce a method for lowering the mortality, morbidity, and other postoperative complications after pancreaticoduodenectomy.METHODS: From January 1991 to December 2001, twenty-six patients were treated using one-layer pancreaticojejunostomy. The mean age of these patients was 52.3 years. Some of these patients were complicated by hypoproteinemia, anemia and jaundice. All patients were subjected to pancreaticoduodenectomy, reconstruction of the digestive tract by Child's method, and one-layer or Braun's anastomosis after pancreaticojejunostomy, choledochojejunostomy, and gastrojejunostomy.RESULT: No death and pancreatic fistula were observed after operation.CONCLUSION: One-layer pancreaticojejunostomy is simple and safe.

关键词： one-layer, pancreaticojejunostomy pancreaticoduodenectomy