15 research outputs found

    Mechanistic Study of Methane Partial Oxidation to Synthesis Gas over Pt/Al2O3、Ir/SiO2 and Ru/SiO2 Catalysts

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    本文以探明Pt/Al2O3、Ir/SiO2和Ru/SiO2等催化剂上甲烷部分氧化(POM)制合成气反应机理为目的,首先采用原位显微Raman光谱技术,对POM反应起燃前后催化剂床层前部贵金属物种的化学态以及由甲烷解离所生成的碳物种进行了详细的表征。在此基础上采用脉冲实验技术在POM反应条件下对Ar稀释的CH4/O2,CH4/H2O,CH4/CO2和CH4/H2O/CO2等混合气在相关催化剂床层前部(氧化区)和后部(重整区)的反应情况进行了考察,并将实验结果与Raman光谱的表征结果进行了关联,最后采用CD4,D2O和18O2同位素示踪技术,进一步考察了Ir/SiO2催化剂氧化区上氢气和一氧化碳...In this study, we report a mechanistic study on the partial oxidation of methane (POM) to synthesis gas over Ru/SiO2, Pt/Al2O3 and Ir/SiO2 catalysts by using in situ microprobe Raman spectroscopy to probe the catalyst located at the entrance of the catalyst bed during the catalytic ignition process (rt ~ 700 C) of the POM reaction for chemical state of the metals as well as the carbon species that...学位:理学博士院系专业:化学化工学院化学系_物理化学(含化学物理)学号:2052008015019

    焙烧气氛对Ru/Al_2O_3催化剂上甲烷部分氧化制合成气反应性能的影响

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    采用气相色谱、质谱和原位时间分辨红外光谱等技术对空气和Ar气氛中焙烧的Ru/Al2O3催化剂样品上甲烷部分氧化(POM)制合成气反应进行了跟踪,并采用化学吸附、X射线衍射、拉曼光谱和H2-程序升温还原等技术对催化剂进行了表征.结果表明,在Ru/Al2O3-Air上POM反应出现振荡现象,而在Ru/Al2O3-Ar上则可较平稳地进行.经600°C还原后,Ru/Al2O3-Air上Ru的分散度仅为1%,而Ru/Al2O3-Ar上接近9%.这是导致两种样品上POM反应性能差异的主要因素.新鲜催化剂上存在两类Ru物种,分别是与载体相互作用较弱、较易还原的RuO2物种以及与载体相互作用较强、较难还原的Ru-O-Al物种.前者在POM反应过程中被还原为金属Ru0,后者则可随温度的升降发生周期性的还原和氧化,进而改变催化剂对CH4燃烧、重整或部分氧化等反应的相对活性,导致Ru/Al2O3-Air上POM反应尾气中各组分的浓度随时间而发生振荡

    STUDY ON THE CONSTRUCTION AND IMMUNOLOGY CHARACTERISITCS of SIX-VA-LENT FUSION TOXIN of FOOD POISONING-BORNE BACTERIA

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    [目的]构建4种食源性致病菌融合毒素基因及重组表达载体,制备六联融合毒素的血清抗体。[方法]采用柔性lInkEr序列(g-g-g-g-S)对目的基因进行串联(HblA-VT1b-SEA-VT2b-bOnTAHC-SEb),构建重组表达质粒PET-22b(+)-f6并在E.COlI bl21中进行表达,将表达蛋白纯化后免疫豚鼠制备血清抗体,利用ElISA和琼脂扩散试验验证抗体的特异性与敏感性。[结果]成功构建了重组表达质粒PET-22b(+)-f6并在E.COlI bl21中成功表达,37℃表达蛋白主要以包涵体形式存在(表达量10.2%),基因序列全长3384bP,编码1127个氨基酸,蛋白分子量为127205,测序结果与设计序列一致性为100%。ElISA和琼脂扩散试验表明,融合毒素f6与4种食源性致病菌有良好的反应原性,与多种非目标菌不反应。[结论]成功构建了多联融合毒素基因的表达质粒及制备了抗血清,为利用融合毒素的方法检测食源性致病菌,进而建立食源性致病菌广谱、快速的检测方法奠定基础。[Objective] To construct toxin including fusion toxin gene from food poisoning bacteria and its recombinant expression vector,and then prepare serum antibody of Six-valent fusion toxin.[Methods] Six gene(HblA—VT1B—SEA— VT2B—BoNTaHc—SEB)fragments were connected by SOE-PCR via linker sequence encoding five amino acids(G-G-G-G-S),the recombination expression plasmid pET-22b(+)-F6 was constructed and expressed in E.coli BL21.The expression proteinum was purified,and the blood serum was prepared by the immune cobaya,The specificity and sensitivity of antibody were verified by the ELISA and agar diffusion reaction.[Results] The fusion gene F6(HblA—VT1B—SEA—VT2B—BoNTaHc—SEB)and re-combinant plasmid pET-22b(+)-F6 was successfully constructed.The most of the 37℃ expression proteinum showed to be cyt-orrhyctes(expreesion amounted to 10.2%).The sequence encoding the mature fusion protein of the F6 toxin gene was 3384bp,encoding 1127 amino acids.The molecular weight of recombinant fusion toxin protein was 127.205 ku.The result of sequencing was consistent with predicted gene sequences.The results of ELISA and agar diffusion reaction demonstrated that fusion gene F6 and other four kinds of food poisoning-born bacteria had favorable reactionogenicity and did not response to many other non-tar-get bacteria.[Conclusion] The expression plasmid of multi-valent fusion toxin was successful constructed and antiserum was prepared,which laid the foundation for establishing broad spectrum and rapid detection method for food poisoning bacteria by utilization of fusion toxin detection methods.国家自然基金资助项目(30671762);厦门市科技计划项目(3502Z20055009

    核移植方法和活化方法对小鼠体细胞克隆胚胎发育的影响

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    轮叶马先蒿危害现状及防除对策

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    轮叶马先蒿(Pedicularis myriophylla)在新疆巴音布鲁克高寒草地大面积发生,于2004-2005年5月初对其生物学特性、传播方式、分布面积、群落数量特征等进行了观测和调查,并对其进行分析,以了解害草轮叶马先蒿在巴音布鲁克高寒草地的分布情况及其对畜牧业的危害现状。结果表明:轮叶马先蒿的危害面积已高达4.11×104hm2,5月下旬是其种子萌发最活跃时期,产种量高,种子传播是主要的传播方式。将轮叶马先蒿分布面积分为重度、中度和轻度发生区,且随着危害程度的增加,轮叶马先蒿密度和盖度显著增大,而群落的多样性、均匀度和物种丰富度却逐渐降低。轮叶马先蒿种群的生物量占总生物量的比例逐渐增加,禾本科和杂类草的生物量有降低的趋势。针对当地的群落问题,提出了人工和化学防除,同时应建立合理的草地放牧体系,控制和规定合理的草地载畜量,并与围封、补播、施肥等草地改良措施相结合,有效控制轮叶马先蒿的危害和蔓延,改善当地的生态与环境,使当地群落健康、稳定发展

    巴音布鲁克高寒草原羊茅(Festuca ovina)群落生态位特征

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    为了解高寒草原羊茅群落植物生态位特征,运用Levins生态宽度指数和Cowell生态位相似性比例,对巴音布鲁克羊茅群落植物生态位宽度及生态位相似性比例进行计算。结果表明:9种植物4个资源维上羊茅的生态位宽度最大,其次为黄花棘豆、委陵菜,说明羊茅对环境的适应能力最强。生态位宽度较大的羊茅和紫花针茅与其他物种生态位相似性比例最高,说明羊茅和紫花针茅与其他物种存在着较大的资源竞争。而生态位较小的物种与其他物种生态位相似性比例较小。放牧使得羊茅群落内物种发生变化,在放牧压力持续增大的情况下,以羊茅和紫花针茅为优势种群的草原将向以黄花棘豆和委陵菜占优的退化方向演替

    Functional connectivity difference of theory of mind related brain regions in different age groups of individuals with autism aged 6-18 years old

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    目的:分析社会认知中心理推理能力(ToM)相关重要脑区与其他脑区功能连接的随年龄发育模式,探讨孤独症核心症状社会交往障碍的脑机制。方法:43例6~18岁符合美国精神障碍诊断与统计手册第4版孤独症诊断标准的患者及年龄、性别组间匹配的39例正常对照,选取背内侧前额叶(dMPFC)、左侧颞顶联合(1TPJ)、右侧颞顶联合(rTPJ)和右侧颞上沟(rSTS) 4个ToM相关的重要脑区,计算其与全脑体素之间的功能连接,通过单变量方差分析探索感兴趣区域的功能连接在被试中的组别及年龄交互作用;并将被试根据年龄分为儿童期(6.0~11. 9岁)和青春期(12.0~18.0岁),探讨不同年龄段的组间差异。结果:rTPJ与右侧缘上回及左侧顶下小叶的功能连接、rSTS与双侧额上/中回的功能连接均呈现出组别与年龄的交互作用(校正后P <0.05);而青春期,rTPJ和rSTS存在显著交互效应的功能连接均小于正常对照组(均

    Review on the application of acupoint sticking therapy for constipation in adult patients (中医穴位贴敷疗法在成人便秘中的应用研究进展)

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    Constipation is a common digestive system disease caused by bad living habits or gastrointestinal dysfunction. The purpose of this paper is to summarize the risk factors, epidemiological investigation, Traditional Chinese Medicine cognition and treatment principles of constipation in adult patients, and analyze the research status of Traditional Chinese Medicine acupoint application therapy for constipation in adult patients, in order to provide a reference for the clinical practice and further exploration of appropriate techniques of Traditional Chinese Medicine. (便秘是由于不良的生活习惯影响, 或者胃肠道功能紊乱造成的生活中常见的一种消化系统疾病。本文旨在通过对成人便秘患者的危险因素、流行病学调查、中医认知及治疗方案等进行总结归纳, 以期为中药穴位贴敷疗法应用于成人便秘患者的临床护理提供参考, 为中医适宜技术应用于便秘患者的探索提供可循依据。
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