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Chinese Journal of Chemistry 2004年第6期22卷 568-572页

作者：钱延龙 bala Muhammad D. 谢小敏黄吉玲 Laboratory of Organometallic Chemistry East China University of Science and Technology Shanghai 200237 China

Yan-Lon.bala, Muhammad D. XIE, Xiao-Min(hUAnG, Ji-Ling*Laboratory of Organometallic Chemistry, East China University of Science and Technology, Shanghai 200237, China Benzyl-substituted cyclopentadienyl lanthanide complexes were synthesized and characterized by elemental analysis, MS and IR spectroscopy. The analytical data point out the formation of monomeric, unsolvated complexes. In conjunction with Al(Et)3 as co-catalyst, the title complexes are efficient catalysts for the syndiotactic polymeriza-tion of methyl methacrylate. For the complex (C6h5Ch2C5h4)2YCl, under the optimum polymerization conditions (60 ℃, n(MMA)∶n(catalyst)∶n(co-catalyst)=1000∶1∶10), a predominantly syndiotactic (rr=66%) polymer of high molecular weight (Mh=105000) was obtained.

关键词： benzyl-cyclopentadiene organolanthanide complex methyl methacrylate syndiotacticity polym-erization

Preliminary study on modelling, fabrication by photo-chemical etching and in vivo testing of biodegradable magnesium AZ31 stents

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Bioactive Materials 2021年第6期6卷 1663-1675页

作者： bala Subramanya Pavan Kumar Kandala Guangqi Zhang Capucine LCorriveau Mark Paquin Madeleine Chagnon Dana Begun Vesselin Shanov Department of Mechanical and Materials Engineering University of CincinnatiOH45221USA Department of Chemical and Environmental Engineering University of CincinnatiOH45221USA Charles River Laboratories Montreal ULC BoisbriandQuebecJ7H 1N8Canada Medical Products Market Consulting IncIndianapolisIN46202USA Waygate Technologies Baker HughesCincinnatiOH45241USA

Magnesium metal(Mg)is a promising material for stent applications due to its biocompatibility and ability to be resorbed by the *** of stents by laser cutting has become an industry *** alternative approach uses photo-chemical etching to transfer a pattern of the stent onto a Mg *** this study,we present three stages of creating and validating a stent prototype,which includes design and simulation using finite element analysis(FEA),followed by fabrication based on AZ31 alloy and,finally,in vivo testing in peripheral arteries of domestic *** to the preliminary character of this study,only six stents were implanted in two domestic farm pigs weighing 25-28 kg and they were evaluated after 28 days,with an interim follow-up on day *** left and right superficial femoral,the left iliac,and the right renal artery were selected for this *** diameters of the stented artery segments were evaluated at the time of implantation,on day 14 and then,finally,on day 28,by quantitative vessel analysis(QVA)using fluoroscopic *** Coherence Tomography(OCT)imaging displayed some malposition,breaks,stacking,and protrusion into the lumen at the proximal,distal,and mid-sections of the stented *** stents degraded with time,but simultaneously became embedded in the *** 28 days,the animals were euthanized,and explanted vessels were fixed for micro-CT imaging and histology ***-CT imaging revealed stent morphological and volumetric changes due to the in-body *** in vivo corrosion rate of 0.75 mm/year was obtained by the CT *** histology suggested no-life threatening effects,although moderate injury,inflammation,and endothelialization scores were observed.

关键词： Magnesium alloy FEA modelling Stents Photo-chemically etching Micro-CT histology

五配位单核钴配合物的单晶结构和磁性能（英文）

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无机化学学报 2019年第5期35卷 910-914页

作者：张翠娟 Sukhen.bala 倪兆平童明良中山大学化学学院生物无机与合成化学教育部重点实验室广州510275

制备了五配位单核钴配合物[Co(TMC)Cl]ClO_4(1,TMC=1,4,7,10-tetramethyl-1,4,7,10-tetraazacyclododecane)。配合物1结晶于单斜晶系:P21,晶胞参数为a=0.805 95(7) nm,b=1.486 58(12) nm,c=0.813 64(7) nm,β=110.190(2)°,V=0.914 93(13) nm^3,Z=2,T=120(2) K。钴与来自TMC配体的4个氮原子和1个氯离子配位,形成了扭曲的四方锥配位构型。磁性测试揭示了高自旋的钴离子具有场诱导的慢弛豫行为。

关键词：五配位钴(Ⅱ)配合物磁性能

Synthesis and Characterisation of Colorants Derived from 1,4-Diamino Anthraquinone Polyamides

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Advances in Chemical Engineering and Science 2012年第2期2卷 300-308页

作者： Mohammed Kabir Yakubu Mohammad Sani Gumel Mansur bala Ibrahim Rakesh Kumar Centre for Scientific and Industrial Research (CSIR) Materials Science and Manufacturing Port Elizabeth South Africa Department of Pure and Industrial Chemistry Bayero University Kano Nigeria Department of Textile Science and Technology Ahmadu Bello University Zaria Nigeria

In this study, the polycondensation products of a diamine anthraquinone (1,4-diamino anthraquinone) and some aliphatic diacids with different methylene numbers were synthesised. Their UV-visible spectroscopy and thermal properties were then characterised. The synthesis was achieved by reacting equimolar solutions of the amine and the acid halides. The structure and thermal properties of the products were characterised. FT-IR Spectra of all the three products revealed the formation of amide due to the presence of strong bands at 1565 and 3390 cm?1 assignable to C=O stretching and n-h vibrations. Differential Scanning Calorimetry revealed high melting exotherms for the products. Thermogravimetry revealed moderate thermal stabilities for Poly nAM and Poly nAS and low thermal stability for Poly nAA which indicated 5.9%, 7.1% and 61.2% weight losses at 285℃, 285℃ and 374℃ for the three products respectively. The wavelengths of maximum absorbance for the dye samples are 601.5, 591 and 589 nm respectively with absorptivity coefficients (a1cm1% ) of 11640000, 11610000 and 11560000 respectively.

关键词： Anthraquinone Polymeric Dyes Polyamide Synthesis Characterisation

Impact of Climate Change on Vegetation Distribution and net Primary Productivity of Forests of himalayan River Basins: Brahmaputra, Koshi and Indus

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American Journal of Climate Change 2018年第2期7卷 271-294页

作者： A. Chaitra S. Upgupta L. D. Bhatta J. Mathangi D. S. Anitha K. Sindhu Vidya Kumar n. K. Agrawal M. S. R. Murthy F. Qamar Indu K. Murthy J. Sharma R. K. Chaturvedi G. bala n. h. Ravindranath Centre for Sustainable Technologies Indian Institute of Science Bengaluru India International Centre for Integrated Mountain Development (ICIMOD) Kathmandu Nepal Divecha Centre for Climate Change Centre for Atmospheric Sciences Indian Institute of Science Bengaluru India

The impacts of climate change in terms of forest vegetation shifts and net Primary Productivity (nPP) changes are assessed for Brahmaputra, Koshi and Indus river basins for the mid (2021-2050) and long (2071-2100) terms for RCP4.5 and RCP8.5 scenarios. Two Dynamical Global Vegetation Models (DGVMs), Integrated BIosphere Simulator (IBIS) and (Lund Postdam and Jena (LPJ), have been used for this purpose. The DGVMs are driven by the ensemble mean climate projections from 5 climate models that contributed to the CMIP5 data base. While both DGVMs project vegetation shifts in the forest areas of the basins, there are large differences in vegetation shifts projected by IBIS and LPJ. This may be attributed to differing representation of land surface processes and to differences in the number of vegetation types (Plant Functional Types) defined and simulated in the two models. however, there is some agreement in nPP changes as projected by both IBIS and LPJ, with IBIS mostly projecting a larger increase in nPP for the future scenarios. Despite the uncertainties with respect to climate change projections at river basin level and the differing impact assessments from different DGVMs, it is necessary to assess the “vulnerability” of the forest ecosystems and forest dependent communities to current climate risks and future climate change and to develop and implement resilience or adaptation measures. Assessment of the “vulnerability” and designing of the adaptation strategies could be undertaken for all the forested grids where both IBIS and LPJ project vegetation shifts.

关键词： Climate Change Forests himalayan River Basins Impacts nPP Change Forest Type Shift

欧洲成人首次行肝移植术后3个月和12个月的病死率:患者预后的预测模型

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世界核心医学期刊文摘（胃肠病学分册） 2006年第4期2卷 2-3页

作者： Burroughs A.K sabin C.A Rolles K. 廖新华 Liver Transplantation and hepatobiliary Medicine Royal Free Hampstead NHS Trust London NW3 2QG United KingdomProf.

Background: Mortality after liver transplantation depends on heterogeneous recipient and donor factors. Our aim was to assess risk of death and to develop models to help predict mortality after liver transplantation. Methods: We analysed data from 34 664 first adult liver transplants from the European Liver Transplant Registry to identify factors associated with mortality at 3-months (n = 21 605 in training dataset) and 12-months (n = 18 852 in training dataset) after transplantation. We used multivariable logistic regression models to generate mortality scores for each individual, and assessed model discrimination and calibration on an independent validation dataset (n = 9489 for 3-month model and n = 8313 for 12-month model). Findings: 2540 of 21 605 (12%) individuals in the 3-month training sample had died by 3 months. Compared with those transplanted in 2000-03, those transplanted earlier had a higher risk of death. Increased mortality at 3-months post-transplantation was associated with acute liver failure (adjusted odds ratio 1.61), donor age older than 60 years (1.16), compatible (1.22) or incompatible (2.07) donor-recipient blood group, older recipient age (1.12 per 5 years), split or reduced graft (1.96), total ischaemia time of longer than 13 h (1.38), and low United network for Organ Sharing score (score 1: 2.43; score 2: 1.67). however, cirrhosis with hepatocellular carcinoma, alcohol cirrhosis, hepatitis C or primary biliary cirrhosis, donor age 40 years or younger, or less, hepatitis B, and larger size of transplant centre (≥70 transplants per year) were associated with improved early outcomes. The 3-month mortality score discriminated well between those who did and did not die in the validation sample (C statistic = 0.688). We noted similar findings for 12-month mortality, although deaths were generally underestimated at this timepoint. Interpretation: The 3-month and 12-month mortality models can be effectively used to assess outcomes both within and

关键词：肝移植预测模型模型组异质性酒精性肝硬化缺血时间急性肝衰竭预后改善肝细胞癌训练样本

氮和碳共掺杂TiO_2纳米晶的制备及可见光催化性能

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高等学校化学学报 2012年第12期33卷 2716-2721页

作者：哈日巴拉郭金毓阿茹娜原光瑜张战营刘宗瑞内蒙古民族大学化学化工学院通辽028043 河南理工大学材料科学与工程学院焦作454003

以钛酸四丁酯为钛源,冰醋酸为抑制剂,超细铵盐为固体载体,采用新型溶胶-凝胶法制备了氮和碳共掺杂TiO2纳米晶(n-C-TiO2)光催化剂.透射电子显微镜(TEM)结果表明,n-C-TiO2样品颗粒均匀,尺寸细小,且分散性好;热失重分析(TGA)、X射线粉末衍... 详细信息

以钛酸四丁酯为钛源,冰醋酸为抑制剂,超细铵盐为固体载体,采用新型溶胶-凝胶法制备了氮和碳共掺杂TiO2纳米晶(n-C-TiO2)光催化剂.透射电子显微镜(TEM)结果表明,n-C-TiO2样品颗粒均匀,尺寸细小,且分散性好;热失重分析(TGA)、X射线粉末衍射(XRD)和X射线光电子能谱(XPS)研究结果表明,复合干凝胶经低温热处理,使铵盐载体分解、挥发去除,样品为单一的锐钛矿相,n和C原子扩散进入晶格结点或间隙位置,与TiO2化学键结合;氮气等温吸附-脱附结果表明,样品比表面积高达356 m2/g,孔体积为0.27 mL/g.以氙灯为可见光光源,罗丹明B水溶液为模拟污染物,P25为参比催化剂,在辐射强度为100mW/cm2的可见光照射条件下,n-C-TiO2具有很高的光催化活性,其可见光催化活性明显高于P25.

关键词：溶胶-凝胶法氮和碳共掺杂 TiO2纳米晶光催化剂

回肠袋-肛管吻合术、传统回肠造口术及回肠直肠吻合术对胆固醇代谢的影响

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世界核心医学期刊文摘（胃肠病学分册） 2005年第2期1卷 6-7页

作者： nissinen M.J. Gylling h. Jrvinen h.J. Miettinen T.A. 陈云茹

Proctocolectomy modifies the enterohepatic circulation and activity of bacteri al enzymes depending on the structure of the stoma and function of the terminal ileum. We evaluated in our comparative study effects of different colectomy cons tructions on cholesterol metabolism. Levels of lipoprotein cholesterol and trigl ycerides, noncholesterol sterols, and squalene in serum, fecal fat, and bile aci ds, cholesterol absorption efficiency, and cholesterol metabolism by sterol bala nce technique were analyzed in human subjects with ileal pouch-anal anastomosis (n=34), conventional ileostomy (n =8), ileorectostomy (n =6), and controls (n = 29). Malabsorption of bile acids, but not of fat, and low serum levels of total and low-density lipoprotein cholesterol, but high levels of high-density lipop rotein cholesterol and increased cholesterol synthesis were evident in the colec tomy groups. In contrast to the ileorectostomy group, expressing high absorption and biliary secretion of cholesterol, a low cholesterol absorption percentage a ccompanied by elevated serum proportions of cholesterol precursor sterols and ph ytosterols characterized the ileal pouch-anal anastomosis and conventional ileo stomy groups. After colectomy, fecal excretion of secondary bile acids was low, wher eas relative proportions of identifiable bile acids remained the same in each st udy group. Low serum levels of total and lowdensity lipoprotein cholesterol of c olectomized subjects may decrease the risk of premature atherosclerosis. The fav orable serum lipid profile was due to enhanced fecal loss of cholesterol as bile acids despite abnormally high cholesterol synthesis. Ileal dysfunction probably diminished cholesterol absorption in subjects with ileal pouch-anal anastomosi s and conventional ileostomy, with no explanation for those with ileorectostomy with no clinical gastrointestinal dysfunction. Relative synthesis of identifiabl e primary bile acids remained unchanged postoperatively, but forma

关键词：回肠袋回肠直肠吻合术回肠造口术胆固醇代谢结肠切除术结肠直肠切除术末端回肠吸收障碍吻合口肠功能障碍

头孢曲松钠短期治疗脑膜炎球菌性脑膜炎与长效氯霉素一样有效:一项随机非劣性研究

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世界核心医学期刊文摘（神经病学分册） 2005年第11期1卷 4-5页

作者： nathan n. Borel T. Djibo A. P.J. Guerin 谢琰臣 Dr.Epicentre 8 rue Saint Sabin 75011 Paris France

Background: In sub-Saharan Africa in the 1990s, more than 600 000 people had epidemic meningococcal meningitis, of whom 10%died. The current recommended treatment by WhO is short-course long-acting oily chloramphenicol. Continuation of the production of this drug is uncertain, so simple alternatives need to be found. We assessed whether the efficacy of single-dose treatment of ceftriaxone was non-inferior to that of oily chloramphenicol for epidemic meningococcal meningitis. Methods: In 2003, we undertook a randomised, open-label,non-infer-iority trial in nine health-care facilities in niger. Participants with suspected disease who were older than 2 months were randomly assigned to receive either chloramphenicol or ceftriaxone. Primary outcome was treatment failure (defined as death or clinical failure) at 72 h, measured with intention-to-treat and per-protocol analyses. Findings: Of 510 individuals with suspected disease, 247 received ceftriaxone, 256 received chloramphenicol, and seven were lost to follow-up. The treatment failure rate at 72 h for the intention-to-treat analysis was 9%(22 patients) for both drug groups (risk difference 0.3%, 90%CI -3.8 to 4.5). Case fatality rates and clinical failure rates were equivalent in both treatment groups (14 [6%] ceftriaxone vs 12 [5%] chloramphenicol). Results were also similar for both treatment groups in individuals with confirmed meningitis caused by neisseria meningitidis. no adverse side-effects were reported. Interpretation: Single-dose ceftriaxone provides an alternative treatment for epidemic meningococcal meningitis-its efficacy, ease of use, and low cost favour its use. national and international health partners should consider ceftriaxone as an alternative first-line treatment to chloramphenicol for epidemic meningococcal meningitis.

关键词：短期治疗替代药物脑膜炎患者远期疗效试验结果撒哈拉以南非洲地区奈瑟菌随机开放油剂