有机-无机杂化纳米材料的制备、表征及性质

利用低温固相反应首次制备了 [(CH3 ) 4 N] 3 PW12 O4 0 ·6H2 O(Ⅰ ) ,[(CH3 ) 4 N] 6P2 Mo18O62 ·9H2 O(Ⅱ ) ,[HMTAH2 ] 2 ·SiW12 O4 0 ·7H2 O(Ⅲ )等纳米粒子 ,并用红外光谱、透射电镜、X射线粉末衍射等手段进行表征 .结果表明 ,粒子大小均一 ,平均粒子直径为 4～ 8nm ,并具有潜在的电荷转移盐性质及非线性光学性质 .     

扩展青霉脂肪酶的纯化及氨基酸序列测定

扩展青霉 (Pen .expansum)WMC2 0 718所产碱性脂肪酶经离心分离、硫酸铵沉淀、疏水层析、阴离子交换层析以及凝胶过滤等步骤 ,其酶纯化了 18.5倍 ,获得了比活性为 4 2 0 0U mg的纯碱性脂肪酶 ,提取得率 4 8.8%。纯化后的脂肪酶经过SDS 聚丙烯酰胺凝胶电泳 (SDS PAGE)和高效反相色谱 (RP HPLC)检测 ,分别达到了SDS PAGE电泳纯和RP HPLC色谱纯。经SDS PAGE和SephadexG 15 0凝胶过滤色谱 ,分别测得酶的相对分子质量为 2 75 0 0和 2 82 0 0 ,表明该酶以单体形式存在。N末端 2 0个氨基酸残基序列测定的结果为ATADAAAFPDLHRAAKLSSA。该酶的最适作用温度为 30℃ ,在 35℃以下稳定 ,4 5℃处理 30min仅残留 30 %酶活性 ;pH稳定范围在 6 .5～ 10 .5之间 ,最适pH值为 10 .0。阴离子表面活性剂LAS对该酶活性的影响较大 ,而非离子表面活性剂AEO9对酶活性无影响。洗涤剂蛋白酶在规定的添加量范围内 ,对脂肪酶的活性影响较小。     

列阵波导光栅复用器及其应用

介绍用于波分复用的一种新型的无源器件列阵波导光栅 ,分析其工作原理 ,概述制备方法、用途和目前的发展状况 .     

城市区位模式与城市地价研究以四川省德阳市为例

通过对城市用地模式和地价模式之间密切关系的论述,在分别对城市形态、城市的交通、城市规划和城市的环境等影响城市土地地价变化的重要因素进行阐述的基础上,提出了在西部大开发中土地规划及利用中应注意的问题.     

An Action Research Study for Elaborating and Implementing an Electronic Waste Collection Program in Brazil

The objective of this study was to conduct Action Research (AR) to create and implement a WEEE management program that was in line with the BNPSW regulations. The city chosen for this study was São João del Rei (SJDR) located in the state of Minas Gerais, Brazil. Using AR it was possible to structure a WEEE management program that involved stakeholders from the city administration, the Federal University of São João del Rei, and representatives from the private sector. The program ultimately collected 1710 kg of WEEE that received an environmentally appropriate destination. Although no major difficulties were observed with respect to the AR process itself, some challenges were encountered. Lack of infrastructure and hesitance on behalf of the public with respect to implementing WEEE Reverse Logistics were complicating factors. The action research as methodology proved to be highly efficient in dealing with e-waste reverse logistics. It resulted in faster decision making, in turn generating better results. Good decisions were repeated and errors were corrected. The Action Research project highlighted the need for raising public awareness about WEEE disposal. It also showed that the public was ultimately interested in participating and contributing to the proposed WEEE management program. The awareness of the population has led to a significant increase in the amount of collected waste. The model resulting from this research serve as a reference for decision makers in implementing similar programs around the world and to contribute to the existing body of knowledge on the subject.

     

胶溶法制备超细二氧化钛

以ＴｉＣｌ４为原料,采用胶溶法制备超细ＴｉＯ２．研究反应物浓度、胶溶剂用量、胶溶温度、表面活性剂用量等因素对胶溶和萃取过程的影响．摸索出胶溶法制备超细ＴｉＯ２的合理工艺条件．     

延长光照时间和海水驯养钝顶螺旋藻的研究

将淡水湖中生长的钝顶螺旋藻驯养在海水中生长 ,并延长光照提高藻类的收得率 ,从而为开发利用这一资源提供有关的实验依据     

电源电压对伺服放大器动态特性的影响

针对常用的电流并联负反馈放大器,研究电源电压对伺服放大器动态特性的影响。建立伺服放大器的线性模型和考虑饱和特性的非线性模型。利用两种模型研究阶跃信号输入时,电源电压变化对伺服放大器控制电流建立时间的影响。随着电源电压的增大,控制电流建立时间减小,当电源电压达到伺服放大器额定控制电流所对应的输出电压的３￣４倍以上时,电源电压对提高伺服放大器动态性能的作用明显减弱。若考虑伺服放大器效率及电源功率等因素     

预警地震

共振是一种普遍现象,在地震事件中也存在,当一个大震爆发时,其地震波将引起一个已到了孕震晚期的震源体共振,地震波被吸收的能量一般并不多,但却可以作用孕震进程的一种标志,即预警信号。发出信号的大震称为预警地震,地震波是各向异性的,在地震带、纬度和经度的方向占有优势,一些毁城巨震,如唐山７．８级、海原８．５级和日本关东８．２级等地震,原来都存在着预警地震,预警地震的存在对可能发生大震地区的防震起到很重要的参考作用。     

巨型机与网格的应用

高性能计算杌是国家信息基础设施的核心设备，被公认为是一个国家综合国力的重要标志之一。目前世界上许多经济强国为了经济、军事、政治的需要都在加紧研制和开发高速度和高性能的巨型机，巨型机已广泛应用于气象预报、石油勘探、生物医药、新材料研制以及大规模棱武器试验等各个领城。我国在高端计算机领城已形成四大系列，网格应用项目也已正式启动，正在迈入计算机强国的行列。