检索结果-南通市图书馆

A combined DFT and molecular dynamics study of U(Ⅵ)/calcite interaction in aqueous solution

在线全文

学校读者我要写书评

暂无评论

Science Bulletin 2017年第15期62卷 1064-1073页

作者： Jian-Hui Lan Zhi-Fang Chai Wei-Qun Shi Laboratory of Nuclear Energy Chemistry and Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China School of Radiological and Interdisciplinary Sciences (RAD-X) and Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions Soochow University Suzhou 215123 China

Here we present a combined DFT and molecular dynamics study of uranyl(U(vi)) interaction mechanisms with the calcite(104) surface in aqueous solution. The roles of three anion ligands(CO_3^(2-), HCO_3^-,OH^-) and solvation effect in U(vi) interaction with calcite have been evaluated. According to our calculations, water adsorbed on the calcite(1 0 4) surface prefers to exist in molecular state rather than dissociative state. Energy analysis indicate that the positively charged uranyl species prefers to form surface complexes on the surface, while neutral uranyl species may bind with the surface via both surface complexing and ion exchange reactions of U(Ⅵ)→Ca(Ⅱ). In contrast, the negatively charged uranyl species prefer to interact with the surface via ion exchange reactions of U(Ⅵ) →Ca(Ⅱ), and the one with UO_2(CO_3)_2(H_2O)^(2-)as the reactant becomes the most favorable one in energy. We also found that uranyl adsorption increases the hydrophilic ability of the(104) surface to different extents, where the UO_2(CO_3)_3Ca_2 species contributes to the largest degree of energy changes(-53 kcal/mol). Our calculations proved that the(104) surface also has the ability to immobilize U(Ⅵ) via either surface complexing or ion exchange mechanisms under different pH values.

关键词：相互作用机制分子动力学方解石水溶液 vi DFT 离子交换反应表面络合物

Liver stiffness and serum markers for excluding high-risk varices in patients who do not meet Baveno vi criteria

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2019年第35期25卷 5323-5333页

作者： Hong Zhou Jun Long Han Hu Cai-Yun Tian Shi-De Lin Department of Infectious Diseases Affiliated Hospital of Zunyi Medical University Zunyi 563003 Guizhou Province China Department of Infectious Diseases Suining Central Hospital Suining 629000 Sichuan Province China

BACKGROUND The Baveno vi criteria for predicting esophageal varices, i.e., liver stiffness measurement (LSM) 150 × 109/L, identify patients who can safely avoid gastroscopy screening. However, they require further refinement. AIM To evaluate the utility of LSM and serum markers of liver fibrosis in ruling out high-risk varices (HRV) in patients who do not meet Baveno vi criteria. METHODS Data from 132 patients with hepatitis B virus (HBV)-related compensated liver cirrhosis who did not meet the Baveno vi criteria were retrospectively reviewed. MedCalc 15.8 was used to calculate receiver operating characteristic (ROC) curves, and the accuracy of LSM, PLT count, aspartate aminotransferase (AST)- to-PLT ratio index, Fibrosis-4, and the Lok index in predicting HRV were evaluated according to the area under each ROC curve (AUROC). The utility of LSM, PLT, and serum markers of liver fibrosis stratified by alanine transaminase (ALT) and total bilirubin (TBil) levels was evaluated for ruling out HRV. RESULTS In all patients who did not meet the Baveno vi criteria, the independent risk factors for HRV were LSM and ALT. Only the AUROC of Lok index was above 0.7 for predicting HRV, and at a cutoff value of 0.4531 it could further spare 24.2% of gastroscopies without missing HRVs. The prevalence of HRV was significantly lower in patients with ALT or TBil ≥ 2 upper limit of normal (ULN)(14.3%) than in patients with both ALT and TBil 100 × 109/L further spared 39.6% and 43.9% of gastroscopies, respectively, without missing HRVs. CONCLUSION In HBV-related compensated cirrhosis patients who do not meet Baveno vi criteria, the LSM, PLT, or Lok index cutoff stratified by ALT

关键词： Baveno vi Esophageal varices Liver cirrhosis Liver stiffness measurement Serum markers of liver fibrosis

Ozonated graphene oxides as high efficient sorbents for Sr(Ⅱ) and U(Ⅵ) removal from aqueous solutions

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China Chemistry 2016年第7期59卷 869-877页

作者： Xia Liu Xiangxue Wang Jiaxing Li XiangkeWang School of Chemistry and Environment North China Electric Power University Beijing 102206 China Key Laboratory of Novel Thin Film Solar Cells Institute of Plasma Physics Chinese Academy of Sciences Hefei 230031 China Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions Suzhou 215123 China School for Radiological and Interdisciplinary Sciences (RAD-X) Soochow University Suzhou 215123 China NAAM Research Group Faculty of Science King Abdulaziz University Jeddah 21589 Saudi Arabia

Ozone was used to oxidize graphene oxides(GO) to generate ozonated graphene oxides(OGO) with higher oxygen-containing functional groups. The as-prepared OGO was characterized by Fourier transformed infrared spectroscopy(FTIR), scanning electron microscopy(SEM) and X-ray photoelectron spectroscopy(XPS). Based on the results of potentiometric acid-base titrations, the total carboxylic acid concentration on OGO surface was calculated to be 3.92 mmol/g, which was much higher than that on GO surface. The results of adsorption experiments indicated that the adsorption capacities of OGO for Sr(II) and U(vi) removal were improved significantly after ozonization.

关键词：氧化石墨氧化物 vi 水溶液吸附剂傅里叶变换红外光谱 X射线光电子能谱扫描电子显微镜

Left jackknife position:a novel position for laparoscopic hepatectomy

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Cancer 2017年第8期36卷 380-383页

作者： Jian-Cong Chen Rong-Xin Zhang Min-Shan Chen Li Xu Jin-Bin Chen Ke-Li Yang Yao-Jun Zhang Zhong-Guo Zhou State Key Laboratory of Oncology in South China Collaborative Innovation Center for Cancer MedicineSun Yat-sen University Cancer CenterGuangzhou 510060GuangdongP.R.China Department of Hepatobiliary Oncology Sun Yat-sen University Cancer Center651 Dongfeng Road EastGuangzhou 510060GuangdongP.R.China Department of Colorectal Cancer Sun Yat-sen University Cancer CenterGuangzhou 510060GuangdongP.R.China

Background: Laparoscopic hepatectomy for hepatocellular carcinoma(HCC) located in segment Ⅵ, Ⅶ, or Ⅷ of the liver is usually difficult because of poor operative exposure, due to the unique anatomical structure. In this study, we evaluated the practice of laparoscopic hepatectomy with the left jackknife position for patients with HCC located in segment Ⅵ, Ⅶ, or Ⅷ.Methods: A total of 10 patients were enrolled to undergo laparoscopic hepatectomy with the left jackknife position.Tumors located in segment Ⅵ, Ⅶ, or Ⅷ were assessed by preoperative dynamic computed tomography or magnetic resonance imaging. Operation time, intraoperative blood loss, postoperative fasting time, postoperative drainage time, major postoperative complications, and duration of postoperative hospital stay were recorded.Results: All surgeries were successfully completed. None of the patients required conversion to open surgery during the procedure, and no serious postoperative complications were observed.The median tumor size was 31 mm(range 23-41 mm) in diameter, the mean operation time was 166 ± 38 min, the mean intraoperative blood loss was220 ± 135 mL, and the median postoperative hospital stay was 4 days(range 2-7 days).Conclusions: For HCC located in segment Ⅵ, Ⅶ, or Ⅷ, laparoscopic hepatectomy with this novel position—the left jackknife position—is safe and effective during tumor resection by exposing a sufficient operating field.Trial registration ClinicalTrials.gov ID:

关键词： Laparoscopic hepatectomy Hepatocellular carcinoma Segment vi viI or viII Left jackknife position

vibrio spp.from Macrobrachium amazonicum prawn farming are inhibited by Moringa oleifera extracts

在线全文

学校读者我要写书评

暂无评论

Asian Pacific Journal of Tropical Medicine 2015年第11期8卷 899-902页

作者： Raimunda Samia Nogueira Brilhante Jamille Alencar Sales Celia Maria de Souza Sampaio Francisco Geraldo Barbosa Manoel de Araujo Neto Paiva Glaucia Morgana de Melo Guedes Lucas Pereira de Alencar Yago Brito de Ponte Tereza de Jesus Pinheiro Gomes Bandeira Jose Luciano Bezerra Moreira Debora de Souza Collares Maia Castelo-Branco Waldemiro de Aquino Pereira-Neto Rossana de Aguiar Cordeiro Jose Julio Costa Sidrim Marcos Fabio Gadelha Rocha Department of Pathology and Legal Medicine Postgraduate Program in Medical MicrobiologySpecialized Medical Mycology CenterFederal University of Ceara School of Veterinary Medicine Postgraduate Program in Veterinary SciencesState University of Ceara Department of Organic and Inorganic Chemistry Federal University of Ceara

Objective:To investigate the in vitro antimicrobial potential of extracts of stem,leaves,flowers,pods and seeds of Moringu okifera(M.okifera) against vibrio spp.from hatchery water and the prawn Mmrobrachium amazonicum.Methods:The ethanol extracts of stem,leaves,pods and seeds and chloroform extract of flowers of M.oleifera were tested against vibrio cholerue(V.cholerae) serogroups non-O1/non-O139(n=4).vibrio vulnificus(n=l) and vibrio mimicus(n=1).Escherichia coli(E.coli)(ATCC(?) 25922) was used as quality control.vibrio species were obtained from Macmbrachium amazonicum prawns and from hatchery water from prawn farming.The Minimum Inhibitory Concentration(MIC) was determined by broth microdilution method.Results:The best result was obtained with the ethanol extract of pods,which inhibited three strains of the V.choleme,vibrio vulnificus,vibrio minimis and E.coli(MIC range 0.312-5.000 mg/mL).The chloroform extract of flowers was effective against all V.chokrae strains and E.coli(MIC range 0.625-1.250 mg/mL).However,the ethanol extracts of stem and seeds showed low effectiveness in inhibiting the bacterial growth.Conclusions:The extracts of pods,flowers and leaves of M.oleifera have potential for the control of vibrio spp.Further studies are necessary to isolate the bioaetive compounds responsible for this antimicrobial activity.

关键词： Prawn Macrobrachium amazonicum Moringa oleifera vi

Various characterizations of product Hardy spaces associated to Schrdinger operators

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China Mathematics 2015年第12期58卷 2549-2564页

作者： LIU SuYing ZHAO Kai College of Mathematics Qingdao University

For every i = 1, 2, we let Li =-?ni+ vi be a Schr¨odinger operator on Rni in which vi∈ L1loc(Rni)is a non-negative function on Rni. We obtain some characterizations for functions in the product Hardy space H1L1,L2(R... 详细信息

关键词： Hardy空间空间相关产品算子特性非负函数 vi 镍

THE　STUDY　OF　STRUCTURE　AND　DYNAMICS　OF　DINUCLEAR　COMPLEXES　［Mo（vi）］_2－EDTA　AND　［Mo（vi）］_2－EGTABY^1HNMR

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 1996年第6期7卷 567-568页

作者： Rui Fang SONG Fei LI Guang Min LIU You Gang MAO Fei DU(Key Laboratory for Molecular Spectra & Structure. Institute ofTheoretical Chemistry, Jinn University, Changchun. 130023) Key Lab. Molec. Spectra/Structure Institute of Theoretical Chemistry Jilin University Changchun 130023

The 1H and 13C NMR spectra of the dinuclear complexes of molybdenum(vi) withethylenediaminetetraacetic acid ([Mo(vi)]2-EDTA) and 3,12-bis(carboxymethyl)-6.9-dioxa-3,12-diazatetra-decanedioic acid(tMo(vi)]2-EGTA) at various temperatures were measured. The solutionstructure of the two dinuclear complexes was determined and the possible exchange process of theisomers is suggested

关键词： EDTA STRUCTURE STUDY THE DYNAMICS OF COMPLEXES DINUCLEAR 络合试剂 EGTABY~1HNMR AND Mo vi

Sensitized photooxygenation^+——vi. Kinetic studies on the singlet oxygenation of 6-ethyl-3,4-dihydro-2H-pyran-5-carboxylic acid ethyl ester and 6-isopropyl-3,4-dihydro-2H-pyran-5-carboxylic acid ethyl ester

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Chemistry 1991年第6期9卷 506-511页

作者： HUANG Ze-En LIANG Xiao-Guang LEUNG Hiu-Kwong CHAN Yuk-Yee Institute of Photographic Chemistry The Chinese Academy of SciencesBeijing 100101

Kinetic studies of the singlet oxygenation of the title compounds were performed accord- ing to Monroe's method. The reaction rate increases with temperature decreasing, leading to a ne- gative activation enthalpy and a large negative activation entropy. These data are interpreted as the evidence for the intermediacy of an exciplex. The solvent effect on the reaction rate suggests that the “dioxetane” path involves a transition state or an intermediate with significant zwitterionic character. The electronic effect of the substituent is obvious, with electron-withdrawing substituent retarding the reaction and electron-donating substituent increasing the reaction rate. However, steric bulkiness at the 6-position does not play an important role in the reaction rate.

关键词： rate Kinetic studies on the singlet oxygenation of 6-ethyl-3,4-dihydro-2H-pyran-5-carboxylic acid ethyl ester and 6-isopropyl-3,4-dihydro-2H-pyran-5-carboxylic acid ethyl ester Sensitized photooxygenation acid vi

Kinetic studies on the solvent extraction of uranium(vi) from phosphoric acid solution with HDEHP using laser-induced optical fiber fluorimetry

在线全文

学校读者我要写书评

暂无评论

Acta Chimica Sinica English Edition 1989年第6期7卷 504-510页

作者： JIA Wei-Jie ZHOU Zu-Min HE A-Di WANG Zhi-Lin QIN Qi-Zong Department of Nuclear Science Fudan UniversityShanghai

The laser-induced optical fiber fluorimetry has been used for the first time to analyse the concentration of uranium(vi) in the kinetic studies on the extraction of uranium(vi) between 0.5 mol/L H_3PO_4 solution and HDEHP-cyclohexane system with Lewis cell. The effects of stirring speed, temper- ature and concentration of uranium(vi) and HDEHP on the rate of extraction were examined. These data show that the extraction rate of uranium(vi) in this system is controlled by the chemical reaction process at the interface. The rate equations and the rate constants of the forward and reverse ex- tractions were obtained. The mechanism of the extraction has been discussed.

关键词： Kinetic studies on the solvent extraction of uranium HDEHP acid vi