铜锌原子比对CuO-ZnO/Al_2O_3催化剂合成甲醇性能的影响

以铝乳液的形式引入Al,采用反加共沉淀法制备了一系列Cu与Zn的原子比(简称Cu/Zn原子比)不同的CuO-ZnO/Al2O3催化剂;以合成气为原料,在固定床微型连续流动反应器中评价了CuO-ZnO/Al2O3催化剂合成甲醇的性能;采用XRD、H2-TPR和BET等方法对催化剂进行了表征,考察了Cu/Zn原子比对CuO-ZnO/Al2O3催化剂合成甲醇性能的影响。实验结果表明,Cu/Zn原子比的变化对催化剂前体的物相组成和催化剂的活性有明显影响;当Cu/Zn原子比为3时,催化剂的初活性和耐热后活性最高,其前体中含有较多的锌-孔雀石相((Cu,Zn)2CO3(OH)2),该物相分解时生成还原温度较低的CuO-ZnO固溶体,使Cu与Zn的相互作用增强,提高了催化剂的活性

Transition Metal Promoted ZSM-5 Catalysts for the Conversion of Dimethyl Sulfide into Methanethiol

负载过渡金属的zSM-5催化剂用于催化甲硫醚(dMS)转化成甲硫醇(MT)的反应.实验结果表明,催化剂的甲硫醚转化率提高和甲硫醇选择性降低的趋势一样,都是以下顺序:CO/zSM-5>MO/zSM-5>nI/zSM-5>W/zSM-5.表征结果表明,由于过渡金属阳离子(W6+、nI2+、CO3+、MO6+)比Al3+活泼,而改性过程中W6+、nI2+、CO3+、MO6+分别代替了部分Al3+,使得改性催化剂对dMS和MT的化学吸附作用更强.过渡金属的引入使得zSM-5总酸度增强,提高了C―S键的裂解能力,从而改进了催化转化dMS的能力.研究结果发现,在转化dMS的过程中,金属活性位和酸性位之间通过强的协同效应起作用.ZSM-5-supported transition metal catalysts were prepared and used to catalyze the conversion of dimethyl sulfide(DMS) into methanethiol(MT).Test results indicated that the activities of the catalysts for the conversion of DMS increased as follows: Co/ZSM-5>Mo/ZSM-5>Ni/ZSM-5>W/ZSM-5.The decrease in MT selectivity followed the same trend.The characterization results showed that transition metal cations(W6 +, Ni2 +, Co3 +, Mo6 +) replaced some Al3 +sites leading to more active in chemiadsorption of DMS and MT since transition metal cations are more active than Al3 +.The incorporation of transition metals into ZSM-5enhances the total acidity of ZSM-5 and increases its capacity to rupture C―S bonds.This subsequently improves its catalytic behavior in the conversion of DMS.We found that the metal active sites and closely situated acidic sites have a strong synergistic effect when converting DMS

关于“经济发展方式转变进程中的财税政策”的探讨(笔谈)

转变经济发展方式是当前中国的热门话题,而上海在城市发展中又肩负着率先转变的重要任务,在这一意义和背景下,2010年4月24日由上海金融学院学院主办、上海金融学院公共经济管理学院承办的“《中国城市财政发展报告2009/2010:促进‘两个中心’建设的上海城市财政》首发式暨‘经济发展方式转变进程中的财税政策’论坛“在我校举行。与会专家围绕经济发展方式转变进程中的财税政策的“趋势与目标“、“机遇和挑战“、“实施方略“和“地方实践“等四个专题进行研讨,各抒己见,智慧交锋。现将其真知灼见整理摘要与读者分享,以期待更多学者共同关注当前经济发展方式转变进程中的财税政策

普乐可复防治大鼠抗肾小球基底膜肾炎的实验研究

观察普乐可复 (FK5 0 6 )防治大鼠抗肾小球基底膜 (GBM)肾炎的疗效。方法 :复制大鼠抗GBM肾炎模型。实验分 3组 :肾炎 +FK5 0 6组、肾炎对照组及正常对照组。大鼠一次性尾静脉注射抗GBM抗血清后 6h内皮下注射FK5 0 6注射液 (0 5mg·kg-1·d-1) ,至第 2 1d。对照组则给予等量的生理盐水。定期于第 4d、第 14d和第2 1d ,检测大鼠尿蛋白、血清肌酐和尿素氮水平 ,观察肾组织病理学改变 ,以及检测T淋巴细胞转化功能。结果 :肾炎对照组大鼠注射抗血清后于第 4d即出现异常蛋白尿 ,血清肌酐和尿素氮亦持续上升 ;肾小球内可见细胞数增加和新月体形成 ,肾小管内大量蛋白管型 ,GBM呈不规则增厚 ,足突大片融合 ;T淋巴细胞转化功能异常。而肾炎 +FK5 0 6组大鼠上述病变均明显较轻。结论 :FK5 0 6能够明显改善大鼠抗GBM肾炎的肾功能

利用RAPD-PCR探讨天蓝喇叭虫生物群系分化

选择天蓝喇叭虫（Stentor coeruleus）作为研究对象,对武汉市南湖、月湖、关桥3个水体共5个样点天蓝喇叭虫（S.coeruleus）样本的总DNA进行随机扩增多态DNA聚类分析,以检测各个样本的遗传相似性和趋异程度,借以评估样本间的遗传变异度。结果如下：（1）从98条随机引物中筛选12条引物共扩增出89条大小为100～1500bp的清晰条带,平均每条引物扩增出7.4条片段。（2）用Rapdistance1.04分析显示,不同样点样本之间存在着一定的变异,其遗传距离在0.076～0.416之间。（3）构建的聚类图中,南湖3个样点的遗传距离较近,在聚类图上聚成一枝,应该为同一个种群。本试验将为探讨水体原生动物迁徙能力对生物群系分化的影响积累实例资料,更希望可以促进水体原生动物的研究和种间过渡区本质及物种扩散行为的研究

Who are you?

If we were to judge by the photographs sent in with this survey, there are two outstanding images of the typical Spore reader. One is of one or more people, equally men and women it seems, working in a field, tending crops and animals, or running a small piece of processing equipment. The other is of a group of readers in their local information centre, sharing and debating Spore articles. There are other images, more difficult to draw and easier to see in our minds: the dozens of readers, from farmer to researcher to planner, who have said in many ways that Spore is their Internet and their gateway to a world of information. Or the woman in Nigeria who used Spore s articles on AIDS in Agriculture in her speech to the President s National Conference on HIV/AIDS. Or the Senegalese journalist, reminded to visit an urban farm project in Soweto, South Africa, when he read his Spore at the World Summit on Sustainable Development in Johannesburg. Or the Malagasy rural radio journalist who drew succour from contact with Spore during some dark days of transition in his country. Or the development planner in eastern Africa who revised his European agency s approach to hydroponics (the cultivation of plants in nutrient rich water) after reading about its scientific value in Spore. Just who are the readers of Spore? What do you do? Only one in 12 respondents is a direct producer in agriculture. In all, 101 respondents (7.7%) said that they are smallholders, commercial producers, animal breeders, pastoralists, fisherfolk, foresters or seed producers. This does not match the most current image of the Spore reader, although many other readers are also direct producers in their own backyard or small plot, in both town and village. The second largest group of respondents belong to the broad category of enablers and suppliers . These 537 people (40.9%) supply seeds, equipment, financial services, extension services, and marketing advice, or are traders, breeders, processors or consultants. The largest group of respondents, 656 and 49.9% in the survey, occupy a wider circle. These are trainers, teachers and researchers; managers of information centres; agricultural journalists; administrators; veterinarians, scientists and engineers. Where do you work? According to the survey, more than one-third of respondents is employed in the government sector. However, because of great discrepancies in the role of the state in ACP agriculture today, this is not a complete picture. In Ethiopia, for example, there is a very high readership of Spore amongst state-employed extension workers but this is much less the case in, for example, West and Central Africa. NGOs, whether local, national or international, account for one-sixth of respondents, with another 10% in farmers associations and community- based organisations. On a region-by-region basis, the growth of civil society and, conversely, the withdrawal of the state is even more visible. In West and southern Africa, there are more Spore readers in civil society bodies than in government; in Central Africa, there are twice as many. In the Pacific and Caribbean, numbers are lower, and mainly governmental, since they date from when CTA started its work by focusing mainly on the public sector. These figures, in particular in Africa, reflect the growing trend of NGOs assuming more responsibilities and the surging emergence of farmers organisations, which are often regarded as a key phenomenon in the transformation of civil society in the 21st century.If we were to judge by the photographs sent in with this survey, there are two outstanding images of the typical Spore reader.One is of one or more people, equally men and women it seems, working in a field, tending crops and animals, or running..