76 research outputs found

    翔安文教园文献资源共建共享初探

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    厦门翔安文教园分布着厦门大学翔安校区和厦门海洋学院等多座高校,园内各院校图书馆各自为政,缺乏协调与合作。文章提出翔安文教园开展文献资源共建共享的构想,探讨翔安文教园各院校图书馆提高文献利用率和文献保障能力的策略

    New method of variable excitation MFL testing under the condition of small magnetizing apparatus

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    为解决常规储罐和管道的漏磁检测(Mfl)方法中磁化器体积大、耗能多的缺点,提出了一种小型磁化器条件下的变励磁Mfl检测新方法。首先,分析了小磁化器条件下被测钢板磁化状态随外部励磁强度的变化特性,推导了偏置磁化条件下励磁通变化量与漏磁场变化率的关系模型;其次,根据所建立的关系模型,设计了一种新型变励磁Mfl检测探头,并给出变励磁Mfl法的系统实现方案;再次,结合实现方案,搭建了变励磁Mfl相应的实验平台;最后,在该平台上,开展了一系列的物理实验并对实验结果进行了深入讨论。实验结果表明,所提变励磁Mfl法无需对被测钢板进行局部饱和磁化,适合小型磁化器条件并具有较高的灵敏度。变励磁Mfl法为漏磁检测领域提供了一种新的检测思路。In the conventional method of magnetic flux leakage( MFL) testing,the magnetizer is in big volume and with more energy consumption.To solve the problem,a new method of variable excitation MFL testing under the condition of small magnetizer is proposed.First of all,the state of magnetized steel along with the change of the external excitation's intensity under the condition of small magnetizer is analyzed.Secondly,according to the established model,a new type of testing probe for the variable excitation of MFL is designed and a new implementation scheme is proposed.Furthermore,combining with the implementation scheme,an appropriate testing platform of the variable excitation MFL is set.Finally,a series of physical experiments on the platform are carried out and the results of the experiment were discussed.The experimental results show that the proposed method don't need to make local saturation magnetization of tested steel plate,which is suitable for the condition of small magnetizer with higher sensitivity.The new method provides a new testing idea for MFL testing field.国家自然科学基金(51177141); 中央高校基本科研业务项目(2010121041); 航空基金(2012ZD68003)资助项

    嗜人类T淋巴细胞病毒Ⅰ型核心蛋白P24基因的克隆与表达

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    目的 从感染HTLV-1的中国患者外周血单核细胞(PBMCs)中扩增编码HTLV-1核心蛋白P24的cDNA,并在大肠杆菌中进行表达。方法 提取感染者PBMCs基因组DNA,应用巢式PCR方法扩增出HTLV-1核心蛋白P24的cDNA并测序,与pGEX-20T载体构建重组质粒,在大肠杆菌BL21中表达,采用ELISA和Westernblot分析重组蛋白活性。结果HTLV-1核心蛋白P24基因序列高度保守,构建重组载体后,在大肠杆菌中表达的重组蛋白,经检测具有较强的抗原活性。结论 成功地表达了HTLV-1型病毒的核心蛋白P24基因,为国产诊断试剂和疫苗的研发打下了基础

    Adsorption behavior of Fe-Mn binary oxide towards As(Ⅲ) and As(Ⅴ) and its application in biogas slurry

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    研究了铁锰复合氧化物(fMbO)吸附去除AS(Ⅲ)、AS(V)的性能。结果表明fMbO对AS(Ⅲ)、AS(V)均具有较好的吸附能力,其饱和吸附量分别为111.10、71.40 Mg·g-1。AS(Ⅲ)和AS(V)是通过与fMbO表面的fE—OH基团进行交换并形成内层络合物的形式被fMbO吸附,且AS(Ⅲ)的吸附是吸附和氧化共同作用的结果。另外,沼液中共存离子对AS(Ⅲ)和AS(V)的吸附有不同的影响。zn2+能够增加fMbO对AS(Ⅲ)、AS(V)的吸附量,且增加幅度随着zn2+浓度的增加而增加;磷酸根对AS(Ⅲ)、AS(V)的吸附有明显的抑制作用,当磷与砷的分子摩尔比为1时,fMbO对AS(Ⅲ)、AS(V)的吸附量分别降低了34.70%、31.50%;但是有机物(腐殖酸、动物蛋白及尿素)对fMbO吸附AS(Ⅲ)、AS(V)的影响不大。利用fMbO对实际沼液中的砷进行吸附,结果表明砷的去除率平均达到65%左右,使吸附后某些沼液中砷的浓度达到生活饮用水标准和地表水排放标准。因此,将fMbO用于砷污染的沼液及水体的治理具有很好的应用前景。The adsorption behavior of arsenite(As(Ⅲ)) and arsenate(As(Ⅴ)) by Fe-Mn binary oxide(FMBO) was studied.The results indicated that FMBO had strong adsorption ability to both As(Ⅲ) and As(Ⅴ) and the maximum adsorption capacity was 111.10, 71.40 mg·g-1 respectively.As(Ⅲ) and As(Ⅴ) were adsorbed on FMBO surface through forming inner-sphere surface complexes by ligand exchange with hydroxyl groups, and As(Ⅲ) removal by FMBO was through an oxidation and adsorption combined process.In addition, the influences of co-existing substances generally present in biogas slurry were examined.Zinc ion could promote As(Ⅲ) and As(Ⅴ) adsorption on FMBO and the adsorption capacity increased with increasing zinc ion concentration.Phosphate had significant effect on As(Ⅲ) and As(Ⅴ) removal.When P/As ratio was equal to 1, the adsorption capacity of As(Ⅲ) and As(Ⅴ) was reduced by 34.70%, 31.50%, respectively.However, organics, such as humic acid, animal protein and carbamide had no significant effect on As(Ⅲ) and As(Ⅴ) removal.Moreover, FMBO as adsorbent for removal arsenic of actual biogas slurry was investigated.The average removal rate of arsenic of actual biogas slurry was about 65%, decreasing the arsenic concentration of some biogas slurry to the drinking water and surface water discharge standard.Therefore, FMBO could be an attractive adsorbent for both As(Ⅴ) and As(Ⅲ) removal from biogas slurry.国家重点基础研究发展计划项目(2013CB733505); 国家自然科学基金项目(21077086)~

    刺苋的化学成分研究

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    目的研究刺苋Amaranthus spinosus的化学成分。方法采用大孔树脂、硅胶、Sephadex LH-20柱色谱、ODS柱色谱等方法进行分离纯化,利用波谱技术鉴定化合物的结构。结果分离得到了16个化合物,分别鉴定为香草醛(1)、丁香醛(2)、邻苯二甲酸二异丁酯(3)、邻苯二甲酸二丁酯(4)、对羟基苯甲醛(5)、2-羟基苯并噻唑(6)、丁香脂素(7)、hydroxydihydrobovolide(8)、黑麦草内酯(9)、蚱蜢酮(10)、棕榈酸甘油酯(11)、反式阿魏酸酰对羟基苯乙胺(12)、菠甾醇-3-O-β-D-葡萄糖苷(13)、齐墩果酸-3-O-β-D-吡喃葡萄糖醛酸甲酯苷(14)、齐墩果酸-3-O-β-D-吡喃葡萄糖醛酸苷(15)、芦丁(16)。结论化合物1~12、14、15均为首次从该植物中分离得到

    Experimental study on reperfusion of intraocular lens

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    作者简介: 祁明信, 男, 1945 年7 月 出生, 教授、主任医师、博士研究生 导师, 主要从事白内障的基础与临 床研究。联系电话: 0591-83570887; E-mail:qihuang@netease. com 通讯作者: 黄秀榕,E-mail:[email protected][中文文摘]目的开展晶状体再灌注的离体和动物实验研究,并对再灌注人工晶状体技术进行评价。方法采用新鲜离体幼兔眼、离体猪眼、新西兰白兔眼,应用自行研制的人工晶状体材料,进行以下实验:(1)体外固化实验;(2)晶状体前囊膜微型撕囊及其稳固性实验;(3)经微型前囊膜开口超声乳化吸出晶状体内容物实验;(4)活的新西兰白兔眼内人工晶状体再灌注实验。结果(1)按硅酮聚合物与固化剂50:1的比例可获得柔软、弹性好、固化时间短(完全固化时间为60min)的注入材料;(2)晶状体前囊膜1.8~2.0mm的连续环形撕囊口具有较好的稳定性,可经该微型开口吸出晶状体内容物并灌注材料;(3)超声能量18%、流量25mL·min-1、负压120mmHg(1kPa=7.5mmHg)为晶状体内容物经微型前囊膜开口吸出的最佳条件;(4)注入灌注材料后可形成由晶状体囊膜包裹的、置换原晶状体皮质和核的、新的再灌注人工晶状体。结论采用再灌注人工晶状体的方法可进行新型人工晶状体再灌注,可为治疗白内障和老视提供参考。[英文文摘]Objective To carry out the experimental study on reperfusion of intraocular lens(IOLs) in vitro or in animal,and to assess the technique of IOLs reperfusion.Methods The following experiments were performed by using self-developed materials in fresh rabbit eyes and pig eyes in vitro,as well as in eyes of alive New-Zea-land rabbits:(1)Solidification study of self-developed material in vitro;(2)Continuous circular capsulorhexis(CCC) in anterior capsule of lens and its stability;(3)Draw of lens contents via phaco through mini-CCC;(4)IOLs ref illing in the eyes of alive New-Zea land rabbits. Results(1) Thematerialwhich was soft, springy and short-term solidification(full solidification time was 60 minutes) were obtained in certain proportion of geland solidified agent(50:1) in vitro; ( 2)The CCC in anterior capsule of lens with 1.8-2.0 mm diameter had very good stability. The lens contents were drawn and the materialwere refilled through themini-CCC; (3) The best conditions of drawing out lens contents through m ini-CCC were phaco energy 18% , flow 25 mL·min- 1, and negative pressure 120 mmH g (1kPa=7.5 mmHg);(4) The new refilled IOLs, which were wrapped by capsule of lens and were replaced original cortex and nucleus of lens, were obtained after thematerial refillied. Conc lusion. New IOLs are refilled through this method, which can prov ide reference for the treatment of cataract and presbyopia.福建省科技三项费用;教育厅重点资助项目基金资助(编号:K98041

    极小化加权完工时间和的无界批量机器并行调度问题

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    考虑无界批量机器并行调度中极小化加权完工时间和问题.设有n个工件和m台批加工同型机.每个工件具有一个正权因子、一个释放时间和一个加工时间.每台机器可以同时加工B≥n个工件.一个批次的加工时间是该批次所包含的所有工件的加工时间的最大者.在同一批次中加工的工件有相同的完工时间,即它们的共同开始时间加上该批次的加工时间.给出了一个多项式时间近似方案(PTAS)

    克拉玛依市中心城区绿地系统健康现状评价与分析

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    概要地介绍了利用专家打分法、层次分析法以及指数和法模型,构建克拉玛依市中心城区绿地系统研究区的健康评价体系的过程;同时结合该评价体系的评价结果与实际状况,划分了该市绿地种类。通过各主要权重指标分析了克拉玛依市中心城区绿地系统绿地现状,认为该市绿地系统总体处于亚健康状态,从而提出该市提高绿地健康指数的管理对策及措施

    主轴摆动复合滚磨光整加工齿轮理论分析及实验研究

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    提出了一种主轴摆动复合滚磨光整加工齿轮的新方法。建立切削速度与切削角的计算模型,利用Matlab软件分析各参数对切削速度和切削角的影响,理论验证了主轴摆动复合滚磨光整加工的可行性。开发了参数可调的实验装置,加工实验表明,齿面表面粗糙度Ra从0.8 μm左右降到0.3 μm左右,表面刀痕去除且表面纹理一致。结果表明,该方法能够有效地提高齿轮的表面质量,使得齿轮获得均匀性表面

    Dynamic changes of soil NO_3~--N as affected by different N fertilizer application and weed treatments in semi-humid winter wheat field

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    以中等肥力土垫旱耕人为土为供试土壤,在冬小麦(Triticumaestivum)不同生育期采集0—100 cm土层土壤样品,研究不同施肥及杂草处理对半湿润农田生态系统土壤NO3--N动态变化的影响。结果表明,1)土壤剖面NO3--N含量随施氮量增加而显著增加,0—100 cm土层NO3--N累积量与施氮量线性相关;在越冬期、返青期和拔节期,相关系数r分别为0.995、0.971和0.949。2)冬小麦生长过程中,土体NO3--N含量先降低后回升,在拔节期最低;成熟期土壤有机氮矿化产生的NO3--N是收获后土壤剖面残留NO3--N的主要贡献者。3)在越冬期、返青期、拔节期和成熟期,施磷(PN135)与不施磷(P0N135)处理相比,施磷可显著减少土体NO3--N累积量,减少量分别为N61.4、26.9、36.6和5.5 kg/hm2;磷肥对土壤NO3--N残留累积量的削减效应以越冬期表现最为显著,成熟期表现不显著。4)在施磷的基础上,不同杂草处理土壤剖面NO3--N累积量在施氮量为45 kg/hm2(PN45)及90 kg/hm2(PN90)时差异不显著;而在施氮量为180 kg/hm2(即PN180)的高氮处..
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