42 research outputs found

    Preparation, Activation and Polymer Composites of Boron Nitride Nanotubes

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    氮化硼纳米管由于其特殊的结构、性能,引起了人们的广泛兴趣,成为了近年来研究的热点。氮化硼纳米管许多方面的性能表现不同于甚至优于碳纳米管。例如,氮化硼纳米管是带宽很高(约为5.5eV)的半导体,其导电性质与管径和螺旋度没有直接关系。再如,氮化硼纳米管具有比碳纳米管更好的耐高温性能、更高的抗氧化性、更强的抗化学腐蚀性、更优的热传导性质和更好的韧性。这些优良的特性使得氮化硼纳米管在许多领域中有着潜在的应用价值,比如高温下工作的半导体纳米材料、高温热传导纳米复合材料、高温绝缘材料等。本论文研究了氮化硼纳米管的合成、活化及其与高分子材料的复合,并对合成得到的产物进行了结构表征。研究工作分为五章,研究结果...There has been much recent interest in boron nitride nanotubes(BNNTs) for their electronic, thermal, and mechanical properties, which are in many cases different from and/or superior to those of carbon nanotubes. For example, BNNTs are semiconductors with a wide band-gap (5.5 eV) independent of the nanotube chirality or morphology. The thermal conductivity, oxidation resistivity, thermal and chemi...学位:理学博士院系专业:化学化工学院化学系_无机化学学号:1912005140305

    联合检测HBV前S1抗原和核心抗原的临床意义

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    目的:探讨联合检测血清HBV前S1抗原(preS1)和核心抗原(HBcAg)(均为HBV核酸相关抗原,nucleic acids related antigen,HBV NRAg)的意义及临床价值。方法:采用ELISA法对393份HBsAg、HBV DNA双阳性的血清和612份HBsAg阴性血清进行HBV NRAg检测,所有标本均采用多区段巢式PCR确认阳性、阴性,采用荧光定量PCR法进行HBV DNA定量分析。结果:393份HBsAg、HBV DNA双阳性血清中,HBV NRAg阳性为382份,其阳性率为97.2%;612份HBsAg阴性的血清标本中,609份确认为HBV DNA阴性,其中检出2份HBV NRAg阳性,607份为阴性,其HBV NRAg的阴性率为99.7%(607/609),另3份HBsAg阴性血清HBV DNA阳性者,其HBV NRAg均为阳性。结论:联合检测preS1和HBcAg的HBV NRAg可作为临床HBV感染的筛选及判断HBV复制的有意义的补充项目

    大肠杆菌表达的戊型肝炎病毒ORF2多肽对恒河猴的免疫保护研究

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    在大肠杆菌中表达的一段戊型肝炎病毒 (HEV)结构蛋白NE2 ,纯化后以弗氏佐剂 ,按0d ,1 0d ,30d的方案 1 0 μg 针的剂量免疫 3只恒河猴 ,在第 2周抗体阳转 ,第 6周时 1只滴度达 1∶1 0 0 0 0 0 ,另 2只滴度 1∶2 0 0 0 0 ,此时以 1 0 6PCR滴度的HEV病毒粪悬液攻击。对照组 3只均出现血清转氨酶 (ALT)升高 ,抗体阳转 ,粪便持续排毒 1月以上 ;疫苗组无一发病 ,未检出非疫苗来源的抗体 ,其中 1只始终未检出粪便排毒 ,另 2只仅出现短暂排毒。以一份NE2免疫后猴血清 (滴度 1∶2 0 0 0 0 )与 1 0 3PCR滴度的病毒混匀后感染 2只恒河猴 ,结果对照组 2只均持续排毒 3周以上 ,抗体阳转 ,1只ALT明显升高 ;而抗体中和组 2只猴始终未检出粪便排毒 ,抗NE2抗体缓慢下降 ,ALT正常。这些结果表明NE2具有良好的免疫原性和免疫保护性 ,有可能成为有效的戊肝疫苗

    Sodium/calcium exchanger inhibitor SN-6 rescued heart dysfunction and cell death in calcium paradox

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    目的评价钠-钙交换体选择性抑制剂Sn-6对钙矛盾处理造成离体灌注大鼠心脏功能障碍和心肌细胞死亡的影响。方法离体心脏先后经历3 MIn无钙液、30 MIn有钙液灌注即钙矛盾处理,实验同步监测左室功能,并检测复钙期冠脉流出液乳酸脱氢酶(ldH)含量与实验结束时存活心肌组织面积的大小。结果钙矛盾处理使得左室功能丧失,表现为左室舒张末压(lVEdP)显著抬高,左心室发展压(lVdP)、心室压力变化最大速率(±dP/dT)为0;心脏几乎不存在活性组织;于无钙液灌注前2 MIn、无钙液灌注期和复钙后前5 MIn给予10μMOl/l Sn-6处理后,lVEdP显著降低,lVdP和±dP/dT明显恢复,心肌损伤面积缩小,ldH释放减少;Sn-6处理的对照心脏于灌流结束时左室功能没有显著改变。结论 Sn-6具有减轻钙矛盾处理造成的心功能损害,增加细胞存活的作用,提示钠-钙交换体是钙矛盾损伤的关键分子。Objective The present study was to observe the effect of sodium /calcium exchanger inhibitor SN-6 on heart dysfunction and cell death induced by calcium paradox.Methods Calcium paradox in isolated heart was elicited by 3-min calcium depletion followed by 30-min calcium repletion in the absence or presence of 10 μmol/L SN-6,an inhibitor of sodium/calcium exchanger.Cardiac function was monitored,and lactate dehydrogenase(LDH) release during calcium repletion and infarct size was measured.Results Upon calcium repletion,the heart deteriorated,exhibiting a marked depression in cardiac function,an enlarged infarct size and an increase in LDH release.These changes were significantly attenuated by SN-6.SN-6 had no effect on cardiac performance at the end of perfusion under control conditions.Conclusion The results demonstrate that SN-6 rescues heart dysfunction and cell death in calcium paradox.It also indicates that sodium/calcium exchanger is a key molecule in the injury.国家自然科学基金(30971196

    梅毒螺旋体47 ku抗原的分段表达及抗原表位分析

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    通过大肠杆菌表达系统表达了梅毒螺旋体47 ku膜蛋白及其N端和/或C端缺失的重组蛋白共15个,经亲和层析纯化,并通过免疫印迹和酶联免疫实验检测这组蛋白与梅毒病人血清的反应性.结果发现所有包含D结构域的重组蛋白的免疫反应性显著高于不含D结构域的蛋白,提示D结构域中可能包含47 ku膜蛋白上的一个免疫优势表位

    1,3,4,6,7,9-Hexabromo-2,3,4,5,6,7,8,9-octahydro-1H-trindene

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    Each of the six Br atoms in the title compound, C15H12Br6, connects to an alpha-C atom; a pair of adjacent Br atoms connecting to the same five-membered ring extends to one side of the molecular framework and the other two pairs to the other side. The beta-C atoms extend in the opposite direction with respect to the pairs of Br atoms

    Composites of Oxidized Boron Carbonitride Nanotubes with Polyaniline: Preparation and Conductivity Studies

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    通讯作者地址: Huang, RB (通讯作者), Xiamen Univ, State Key Lab Phys Chem Solid Surfaces, Coll Chem & Chem Engn, Xiamen 361005, Peoples R China 地址: 1. Xiamen Univ, State Key Lab Phys Chem Solid Surfaces, Coll Chem & Chem Engn, Xiamen 361005, Peoples R China 2. Xiamen Univ, Dept Chem, Coll Chem & Chem Engn, Xiamen 361005, Peoples R China 电子邮件地址: [email protected] precursors of boron carbonitride nanotubes with different B/N ratios were synthesized. Oxidation with nitric acid afforded oxidized boron carbonitride nanotubes (o-BCNNTs), with which composites with polyaniline (o-BCNNTs/PANI) were prepared by in situ oxidative polymerization. For one of the o-BCNNTs, composites were synthesized with a varying amount of the nanotube (up to 30 wt %), while for the rest the nanotube content was maintained at 30 wt % in each case. It has been found that the conductivity of the oxidized boron carbonitride nanotubes decreases with an increasing BIN ratio and that of the composites increases with an increasing percentage of the o-BCNNTs.National Natural Science Foundation of China 20721001,20525103 National Basic Research Program of China 2007CB81530

    Activation of boron nitride nanotubes and their polymer composites for improving mechanical performance

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    通讯作者地址: Zhou, SJ (通讯作者),Xiamen Univ, Dept Chem, Coll Chem & Chem Engn, Xiamen 361005, Peoples R China 地址: 1. Xiamen Univ, Dept Chem, Coll Chem & Chem Engn, Xiamen 361005, Peoples R China 2. Xiamen Univ, State Key Lab Phys Chem Solid Surface, Xiamen 361005, Peoples R China 电子邮件地址: [email protected] nitride nanotubes (BNNTs) are inappropriate for further chemical derivatization because of their chemical inertness. We demonstrate covalent activation of chemically inert BNNTs by isophorone diisocyanate (IPDI) to form isocyanate group (NCO)-terminated BNNT precursors with an 'NCO anchor' ready for further functionalization. As identified by Fourier transform infrared spectroscopy, a number of molecules or polymers with -COOH, -OH or -NH(2) groups are readily attached to the activated IPDI-BNNTs. The IPDI-BNNT-involving polymer composites have shown mechanical properties are considerably improved due to the good dispersibility of IPDI-BNNTs in the polymer matrix and the strong interfacial interactions between BNNTs and polymers. The methodology reported here provides a promising method to promote the chemical reactivity of BNNTs and covalently modify polymer nanocomposites with improved mechanical performance.973 Program 2011-CB935901 NSFC 21021061 21031004 21171140 Fundamental Research Funds for the Central Universities 201112101

    Two I-h-symmetry-breaking C-60 isomers stabilized by chlorination

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    通讯作者地址: Xie, SY (通讯作者), Xiamen Univ, State Key Lab Phys Chem Solid Surfaces, Coll Chem & Chem Engn, Xiamen 361005, Peoples R China 地址: 1. Xiamen Univ, State Key Lab Phys Chem Solid Surfaces, Coll Chem & Chem Engn, Xiamen 361005, Peoples R China 2. Xiamen Univ, Dept Chem, Coll Chem & Chem Engn, Xiamen 361005, Peoples R China 电子邮件地址: [email protected] abiding surprise in fullerene science is that I-h-symmetric buckminsterfullerene C-60 (ref. 1) (I-h-C-60 or C-#1,812(60), the nomenclature specified by symmetry or by Fowler's spiral algorithm(2)) remains the sole C-60 species experimentally available. Setting it apart from the other 1,811 topological isomers (isobuckminsterfullerenes) is its exclusive conformity with the isolated-pentagon rule(3), which states that stable fullerenes have isolated pentagons. Although gas-phase existence of isobuckminsterfullerenes has long been suspected(4-7), synthetic efforts have yet to yield successful results. Here, we report the realization of two isobuckminsterfullerenes by means of chlorination of the respective C-2v-and C-s-symmetric C-60 cages. These chlorinated species, (C60Cl8)-C-#1,809(1) and (C60Cl12)-C-#1,804(2), were isolated in experimentally useful yields. Structural characterization by crystallography unambiguously established the unique pentagon-pentagon ring fusions. These distinct structural features are directly responsible for the regioselectivity observed in subsequent substitution of chlorines, and also render these unprecedented derivatives of C60 isomers important for resolving the long-standing puzzle of fullerene formation by the Stone-Wales transformation scheme(8-11).NNSF of China,20525103 ,20531050 ,20721001 , 20571062 ,20425312 973 Program 2007CB81530
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