低温催化裂解烷烃法制备碳纳米管

低温催化裂解烷烃法制备碳纳米管陈萍，王培峰，林国栋，张鸿斌，蔡启瑞（厦门大学化学系固体表面物理化学国家重点实验室，厦门，３６１００５）关键词碳纳米管，催化裂解，甲烷碳纳米管的制备与研究是国际上新材料领域的探索热点［１］．由于具有纳米级的管径，碳纳米管..

70年来中国化学海洋学研究的主要进展

我国的海洋化学工作者通过70年来,特别是近30年来的化学海洋学研究,实现了我国与世界先进水平进入同步发展的快车道,其显著的特点是:(1)化学海洋学研究从元素地球化学分布系统转向了以揭示深层次海洋生物地球化学过程为核心的研究;(2)化学海洋学研究实现了多领域、多视点的综合交叉研究;(3)更加关注了人为影响与自然变化共同作用下的海洋生态环境变化研究,对近海和海岸带而言,更加注重从海陆统筹一体化角度探析化学物质的分布迁移特征。本文从生源要素的海洋生物地球化学过程、微/痕量元素与同位素的海洋化学研究、生物过程作用下的化学海洋学过程等角度,重点总结归纳和分析了30年来我国海洋化学研究的重要进展和发展状况,以期对化学海洋学的进一步研究提供借鉴和启迪。中国科学院战略性先导科技专项(XDA23050501)国家基金委–山东省联合基金项目(U1606404

分子氮的电催化还原

对温和条件下分子氮的络合活化已有研究,但用修饰电极法电催化固氮成氨(或肼)尚未见报道,Shilov等曾发现在V(OH)_2-Mg(OH)_2的悬浮液中,V(Ⅱ)可起络合及还原作用,钒固氮酶在缺钼条件下也可活化分子氮,其活性中心可能与钼酶相似,也是通过有机硫配体而定位在蛋白质的肽链上,能否用含有机硫配体的钒表面配合物模拟钒酶,用电催化方法进行电子与能量的偶联从而固氮成氨?本文对此进行了研究

DNA polymorphism difference between root system and rhizosphere soil arbuscular mycorrhizal fungi of Prunus mume by AFLP analysis

应用巢式PCr并进行梅根系与根围土壤丛枝菌根真菌(ArbuSCulAr MyCOrrIHIzAl fungI,AMf)dnA扩增片段长度多态性(AMPlIfIEd frAgMEnT lEngTH POlyMOrPHISM,AflP)的差异比较,研究梅共生AMf的作用机理。结果表明,从18个梅品种的30个根围土壤样品中有28个样品获得纯化的dnA片段,占样品数93.3%,样品平均多态性位点数为6.5个,nEI’S基因多样性为0.3559±0.1382,SHAnnOn信息指数为0.5299±0.1676。与梅根系AMf dnA多态性比较,根围土壤的平均多态性位点数明显较多;且根系AMf的dnA多态性位点绝大多数存在于土壤AMf的dnA多态性位点中,表明根系内AMf是由土壤AMf发育而来;根系与根围土壤AMf dnA的聚类均与梅品种群、品种关联性不强,表明AMf对宿主梅品种或品种群没有特异的共生关系。DNA polymorphism of arbuscular mycorrhizal fungi(AMF) in root system and those in rhizosphere soil of Prunus mume was analyzed through DNA amplification by nested PCR based on AFLP marker.The results show that the purified DNA can be extracted from 28 soil samples, accounting for 93.3% of totally 30 samples, collected from rhizosphere of 18 cultivars, averaging 6.5 loci for each sample.The average genetic identity was 0.3559±0.1382, Shannon information index was 0.5299±0.1676.The number of loci in rhizosphere soil was much more than that of loci in root sample, and most of loci in root sample could be found in soil sample.It was proved that the AMF in root might be developed from soil AMF.The clustered groups of AMF DNA by AFLP marker both from roots and from soils were not connected with cultivar groups or cultivars of P.mume, and indicated that there was no specific symbiotic relationship between AMF and P.mume.国家自然科学基金(30470006); 厦门市科技项目(3502Z20072010;3502Z20112004)~

AFLP analysis of arbuscular mycorrhizal fungi in roots of Prunus mume

第一作者: 蔡邦平，博士，副研究员。主要研究方向: 园林植物与观赏园艺、植物菌根。电话: 0592--2039576 Email : cbangping@ 163.com 地址: 361003 福建省厦门市思明区虎园路25 号厦门市园林植物园。[中文文摘]为了解决梅根系共生的丛枝菌根(AM)真菌难以应用形态学鉴定的问题,以巢式PCR的AFLP方法研究梅根系AM真菌DNA多态性。试验采集梅花期的根系样品,应用改良CTAB法提取总DNA,经纯化处理后,应用巢式PCR扩增根系AM真菌基因片段,进行AFLP分析。结果表明,18个梅品种的30个根系样品中,仅有8个样品经巢式PCR后获得纯化的DNA片段,占试验样品数的26.7%;8个样品共得到指纹图谱带24条,各样品平均多态性位点数为3.0个,Nei’s基因多样性为0.4097±0.0848,Shannon信息指数为0.5968±0.0955;利用Nei’s遗传相似性系数聚类,梅品种根系内AMF基因组DNA的聚类类别与梅"品种群"这一分类级别无相关性。该试验为植物根系共生AM真菌DNA多态性研究提供了一种简便的技术。[英文文摘]DNA polymorphism of arbuscular mycorrhizal fungi (AMF) was analyzed through the method of DNA amplification by nested PCR based on AFLP marker,in order to solve the difficulty of identifying the species of AMF associated with mei flowers (Prunus mume Sieb.et Zucc.).A total of 30 root samples from 18 mei cultivars were collected in the flowering phase from Wuhan Mei Garden as experimental materials.The results show that the purified DNA can be extracted only from eight root samples that account for 26.7% of total root samples.Totally 24 polymorphic loci were obtained from eight sample roots，averaging 3. 0 loci for each sample.The average genetic identity was 0. 409 7 ±0. 084 8，and the Shannon information index was 0. 596 8 ± 0. 095 5． The clustered groups of AMF DNA by AFLP marker from different cultivars were not identical with cultivar groups of P.mume.The results indicate that the AFLP marker technology is a brief and effective method to study the DNA polymorphism for the AMF in the roots of a plant．教育部科学技术研究重点项目(104034);; 国家自然科学基金项目(30670047);; 厦门市科技计划项目(3502Z20072010、3502Z20112004

甲烷氧化偶联制C_2烃La_2O_3基催化剂的研究

本文的实验结果表明,具有开放型本征构型的La_2O_3对甲烷氧化偶联反应有相当好的活性和选择性,在750℃、原料气空速6.O×10~4ml.g~(-1).h~(-1),CH_4:O_2:N_2=3.7:l.0:9.0(V/V)的反应条件下,氧接近全部转化,甲烷转化率达25.4％,C_2烃选择性为43.6％,添加碱土金属(Ca、Sr、Ba)氧化物或碳酸盐能显著地改善催化剂的性能,在上述反应条件下,60mol％Ba-La_2O_3催化剂的C_2烃选择性达到58％

Carbon nanotube prepared by catalytic pyrolysis of methane

Carbon nanotube can be produced by the catalytic pyrolysis of methane on Ni catalyst at 450 degrees C. TEM observation reveals that almost all the carbon filament produced by this method was in the form of tubular structure, Outer-diameter, length of the carbon nanotube as well as their productivity are governed by reaction temperature and the performance of the catalyst, The separation and purification of the carbon nanotube produced from the catalyst powder are easily performed by washing with aqueous solution of nitric acid followed by oven-drying at 200 degrees C; nearly all powder of the catalyst can be removed away and comparatively pure carbon nanotube can be obtained