CHP-1型裂解催化剂的工业运转

新开发的CHP-1型催化裂解催化剂经115天的工业运转,表明可直接用新鲜催化剂开车,高密度催化剂亦能满足流化要求,但应采用较高的温度来适应新催化剂的高活性。工业运行证实它具有良好的活性、选择性及水热稳定性。探讨了工业装置设计的工程问题。     

A General Procedure for Surface Modification of Nano-alumina and Its Application to Dendrimers

A general procedure for surface modification of nano-alumina using N, N＇-dicyclohexyl- carbodiimide （DCC） mediated amidation is reported. Aliphatic and aromatic carboxylic acids reacted smoothly with nano-alumina pretreated with 3-aminopropyltriethoxysilane in the presence of DCC, giving modified aluminas having organic surfaces. The grafted aluminas have been characterized qualitatively by FT-IR or ^13C CPMAS NMR spectroscopy, and quantitatively by thermogravimetric analysis and elemental analysis. The procedure was applied to polyether dendrons bearing carboxyl groups at the focal points, giving successful grafting of dendrimers onto nano-alumina.     

盾构隧道穿越历史建筑的监测与变形控制

由于自重、恒载和附加变载的作用以及地基土体的长期固结,既有建筑产生的变形,本文称之为“既有变形”。地下工程施工引起的既有建筑物变形,本文称之为“增量变形”。建筑物的总量变形为既有变形与增量变形之和。为确保盾构穿越过程中既有建筑物的安全,要对既有建筑的总量变形进行控制;而要确保隧道施工不会对既有建筑产生明显破坏,则要对既有建筑的增量变形进行控制;从而提出要对建筑物的总量变形和增量变形进行控制的双控控制标准。基于建筑物的差异沉降变形,提出了建筑物的空间扭曲变形控制指标。结合上海轨道交通11号线下穿越历史建筑,通过现场检测得到建筑的既有变形。根据双控控制标准,建立穿越过程中既有建筑的差异沉降与空间扭曲的增量变形与总量变形控制指标,施工过程中进行全程监测,结果显示,穿越施工是成功的。     

Synthesis and spectroelectrochemistry of new phthalocyanines with ester functionalities

Metal-free (H₂Pc) and metallophthalocyanines (MPc; M: Co, Zn) with four n-pentyl ester of thioglycolic acid groups have been synthesized by the esterification of the corresponding carboxylic acid derivatives with n-pentanol. The novel phthalocyanine compounds were characterized by elemental analyses, mass, FT-IR and UV-Vis spectral data. The aggregation investigations carried out in different concentrations and solvents indicate that ester substituted metal-free and metallo-phthalocyanine compounds have not shown any aggregation behavior in the concentration range of about 10⁻⁵ M. Electrochemical and in-situ spectroelectrochemical measurements give common MPc based redox behaviors which supported the proposed structure of the complexes. While CoPc gives both metal-based and ring-based redox processes, H₂Pc and ZnPc give only ring-based electron transfer processes. In-situ electrocolorimetric method was applied to investigate the color of the electro-generated anionic and cationic forms of the complexes.     

Inulin polysaccharide having pendant amino acids: Synthesis and characterization

Inulin polysaccharide was esterified with N-protected α-amino acids (N,N′-di-benzylocarbonyl-L -lysine and N-benzylocarbonyl-glycine) under a mild condition (room temperature) and within short reaction times (6 h). The esterification reactions were conducted in the presence of dicyclohexylcarbodiimide and 4-(dimethylamino)pyridine as a catalyst. The optimal reaction time (6 h) was determined by monitoring the concentration of free carboxylic acid of the N-protected amino acids during the reaction. The degree of substitution per fructose unit was 0.95 for inulin-lysine and 1.01 for inulin-glycine. The resulting biopolymer was deprotected by catalytic transfer hydrogenation method using 1,4-cyclohexadiene as an effective hydrogen donor. The structures, molecular weight, and thermal properties of the amino acid esters of inulin were determined by Fourier transform infrared spectroscopy, ¹H and ¹³C NMR, UV, viscosity, and dicyclohexylcarbodiimide. This new modified inulin polysaccharide would have the potential as a biomaterial for biomedical applications. © 1998 John Wiley & Sons, Inc. J. Appl. Polym. Sci. 70: 953–963, 1998     

SDH DCC管理信息通信的协议栈

本文介绍ＳＤＨＤＣＣ协议栈各层的主要内容和特征，特别是面向目标的应用层ＣＭＩＳＥ、ＲＯＳＥ、ＡＣＳＥ，网络层的路由参数以及数据键路层的ＬＡＰＤ。并给出了各层ＰＤＵ间的对应关系。最后举出两种网络单元中协议栈配置的实例。     

DCC／DMAP法合成二茂铁基苯甲酸胆甾醇酯

倒重氮法合成两类二茂铁基苯甲酸，继而研究以N，N-二环己基碳二亚胺（DCC）作脱水剂，用4-二甲胺基吡啶（DMAP）作除水促进剂，胆甾醇与间、对-二茂铁苯甲酸反应合成液晶材料间、对-二茂铁基苯甲酸胆甾醇酯的方法。研究结果表明，该方法反应条件比较温和，用DMAP作除水促进剂时，胆甾醇酯产率比较高。高效酰化催化剂法是十分有效的酰化方法，在合成胆甾醇酯液晶中可较大幅度地提高产品的产率与纯度，简化操作，降低反应毒性。     

传输网DCC通道带宽瓶颈及优化

传统SDH网络DCC通道带宽无法满足日益增长的需求,文章提出了通过将ML-PPP协议应用于SDH网络DCC通道管理的方式.实验结果表明,通过ML-PPP协议将多个物理链路结合到一起,形成一个高带宽的虚拟链路,可以成倍提高DCC通道带宽,从而有效解决传统传输网DCC通道带宽瓶颈问题.     

一种改进的模拟占空比矫正电路

基于PWLL结构的占空比矫正电路虽然克服了传统占空比矫正电路输出时钟上升沿在占空比矫正过程中发生变化的缺点,但其核心电路——频率电压变换电路不能工作在100MHz以上的频率范围,并且随着工作频率的升高,调整范围会变小。采用pullpush电荷泵代替频率电压变换电路,设计了一个工作在200MHz的占空比矫正电路,HSPICE仿真结果表明其调整范围为30%~70%,占空比变化在1个ps以下,达到了设计要求。     

催化裂解轻油抽出芳烃生产导热油的研究

以催化裂解（DCC）轻油抽出芳烃为原料，采用合适的催化剂和加氢精帛工艺，可生产出符合SH／T0677－1999标准的导热油，且凝点低，可在较宽的湿度范围内作为热传导介质使用。