20 research outputs found

    Optimization of Fermentation Conditions of Marine Algicidal Bacterium Microbulbifer sp. BS03 by Uniform Design

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    采用均匀设计法设计和二次多项式逐步回归分析,对一株高效杀塔玛亚历山大藻微泡菌bS03(MICrObulbIfEr SP.)产杀藻活性物质的发酵培养条件进行优化.通过单因素实验筛选出碳源、氮源、PH、培养时间和接种量为显著影响因子,并对5个显著影响因子采用u15(155)水平对培养基进行优化.结果表明bS03最适发酵培养条件为:蔗糖8 g/l,蛋白胨10.50 g/l,初始PH值7.5,培养时间32 H,接种量3.00%.验证试验结果显示,在此条件下该菌发酵液的干重为4.725 g/l,较优化前增加了31.35%,ld50为0.768%,较优化前降低了25.14%.研究结果为杀藻活性物质以及杀藻机理的研究奠定了理论基础.The optimal parameters of fermentation conditions of marine bacterium Microbulbifer sp.BS03 producing algicidal substances against Alexandrium tamarense were obtained by using Uniform Design and quadric polynomial regression methods.Five main factors were achieved through single factor experiments,that is,carbon source,nitrogen source,pH,incubation time and inoculum size.The U15(155) design result showed the optimum conditions of experiment were as follows: sugar 8 g/L,peptone 10.5 g/L,initial pH 7.5,incubation time 32 h,and inoculum size of 3.00%.According to the verification experiment,under the optimal conditions,the dry biomass was 4.725 g/L which was increased by 31.35% and LD50was 0.768% which was decreased by 25.14% compared with those of the basic fermentation conditions.This outcome will help us to separate active substances from complex components in medium and thus to reveal the mechanism of algicidal activity in the future.国家自然科学基金项目(Nos.40930847;31070442);福建省自然科学基金项目(Nos.2012J01150;2010J01223);福建省教育厅项目(No.JA10232);莆田市科技计划项目[No.2011S09(4)]资助;theOpenFundoftheKeyLaboratoryoftheMinistryofEducationforCoastalandWetlandEcosystemsofXiamenUniversity(CWel0902)---

    Preparation of potassium diformate by methyl formate and potassium hydroxide

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    联系人:李清彪. 第一作者:詹国武(1986—),男,学士.[中文文摘]本研究采用甲酸甲酯、氢氧化钾、甲酸为原料,一步反应制备二甲酸钾。系统地考察了影响产品收率的主要因素,优化了工艺条件,结果表明,当n(MF)/n(KOH)=1.20,n(HCOOH)/n(KOH)=1.44,反应时间为30min,反应温度为55℃时,二甲酸钾产品收率可达 98.8%。产品经红外光谱分析及成分测定,符合质量标准。[英文文摘]In this study, methyl formate, potassium hydroxide and formic acid were used as raw materials for one-step synthesis of potassium diformate. The main factors affecting the quality and yield of product were investigated. The optimal conditions for reaction were: molar ratio of MF to KOH 1.20:1, molar ratio of HCOOH to KOH 1.44:1, reaction time 30 min and reaction temperature 55℃. The product met the quality standard of potassium diformate after infrared spectrum analysis and composition determination.厦门大学创新性实验计划资助项

    低龄DDH患儿初次开放复位术中股骨截骨必要性的前瞻性随机对照试验研究方案

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    回顾性研究发现,股骨截骨术并非低龄DDH患儿手术治疗所必须的,而应根据患儿具体情况合理选择;本研究通过多中心前瞻性研究进一步探讨对于18个月至3岁DDH患儿是否要行股骨截骨术。FSODDH项目为一项多中心前瞻性随机对照临床试验研究。研究设计拟招募200名单侧低龄DDH患儿,随机分成股骨截骨组(n=100)和股骨不截骨组(n=100)。股骨截骨组患儿全部采取髋关节开放复位术、骨盆截骨术及股骨截骨术治疗;股骨不截骨组患儿全部采取髋关节开放复位术及骨盆截骨术治疗;术后定期随访至少2年。收集术前、术后1周、术后1个月、术后3个月、术后6个月、术后1年及术后2年的髋关节正位X线影像资料,比较两组患儿的髋臼指数、股骨头坏死率、再脱位率、术中出血量、手术时间和住院天数等临床指标。这一多中心前瞻性研究将能为低龄DDH患儿是否需行股骨截骨术提供循证医学证据

    Optimization of Fermentation Conditions of Marine Algicidal Bacterium Microbulbifer sp. BS03 by Uniform Design

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    通讯作者 Corresponding author (E-mail: [email protected]; [email protected])[中文文摘]采用均匀设计法设计和二次多项式逐步回归分析,对一株高效杀塔玛亚历山大藻微泡菌BS03(Microbulbifer sp.)产杀藻活性物质的发酵培养条件进行优化.通过单因素实验筛选出碳源、氮源、pH、培养时间和接种量为显著影响因子,并对5个显著影响因子采用U15(155)水平对培养基进行优化.结果表明BS03最适发酵培养条件为:蔗糖8 g/L,蛋白胨10.50 g/L,初始pH值7.5,培养时间32 h,接种量3.00%.验证试验结果显示,在此条件下该菌发酵液的干重为4.725 g/L,较优化前增加了31.35%,LD50为0.768%,较优化前降低了25.14%.研究结果为杀藻活性物质以及杀藻机理的研究奠定了理论基础.[英文文摘]The optimal parameters of fermentation conditions of marine bacterium Microbulbifer sp.BS03 producing algicidal substances against Alexandrium tamarense were obtained by using Uniform Design and quadric polynomial regression methods.Five main factors were achieved through single factor experiments,that is,carbon source,nitrogen source,pH,incubation time and inoculum size.The U15(155) design result showed the optimum conditions of experiment were as follows: sugar 8 g/L,peptone 10.5 g/L,initial pH 7.5,incubation time 32 h, and inoculum size of 3.00%. According to the verifi cation experiment, under the optimal conditions, the dry biomass was 4.725 g/L which was increased by 31.35% and LD50 was 0.768% which was decreased by 25.14% compared with those of the basic fermentation conditions. This outcome will help us to separate active substances from complex components in medium and thus to reveal the mechanism of algicidal activity in the future. Fig 7, Tab 5, Ref 20.国家自然科学基金项目(Nos.40930847,31070442); 福建省自然科学基金项目(Nos.2012J01150,2010J01223);; 福建省教育厅项目(No.JA10232);莆田市科技计划项目[No.2011S09(4)]资助

    多氯联苯内分泌干扰作用及机理研究进展

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    西双版纳土地利用/土地覆被变化时空格局分析

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    西双版纳土地利用/土地覆被变化对于区域土地资源合理利用和生态环境保护以及边境安全保障具有重要意义。基于Landsat TM/ETM遥感数据,采用决策树分类方法,获得西双版纳1990年、2000年和2010年3期的土地利用/土地覆被分类数据;从结构变化、类型变化、空间变化3个角度,系统分析1990-2010年间西双版纳的土地利用/土地覆被时空变化规律,并对轮歇地、茶园和橡胶园3个典型地类进行了重点讨论。研究表明:①西双版纳土地利用/土地覆被呈现以"林地-园地-耕地"为主导的地域结构特征,有林地是最为重要的土地覆被类型,橡胶园是最为主要的土地利用类型;②1990-2010年间,土地利用/土地覆被变化速度呈加快趋势,土地利用强度呈增加趋势,近10年来则更为显著;③1990-2010年间,土地利用/土地覆被变化的主要特征是有林地不断减少,橡胶园、旱地和茶园不断增加;有林地为面积减少最多的地类,橡胶园为面积增加最多的地类,轮歇地为增速最快的地类,灌木林地为减速最快的地类;④1990-2010年间,土地利用/土地覆被类型发生转化的地类主要是轮歇地、灌木林地和有林地,主要的转化方向是轮歇地向有林地和灌木林地转化,橡胶园和茶园的主要来源是有林地和灌木林;⑤1990-2010年间,土地利用/土地覆被空间变化较显著的地类是有林地、灌木林地、橡胶园、茶园和轮歇地;有林地呈以减少为主要特征的"南退北进"的空间变化特征,灌木林地呈先增加后减少为主要特征的"西退东进、南退北进"的空间变化特征,橡胶园呈以增加为主要特征的"以景洪市区为中心,北上南进,西拓东扩"的空间变化特征

    钼、钨氧转移酶仿生配合物的EPR和UV-VIS研究

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