电厂锅炉性能测试及优化改造

测试了对某电厂900 t/h电站锅炉,分析了锅炉热力性能,提出,锅炉优化改造方案,使改造达到预期效果。     

气相色谱法测定丙烯中微量烃类杂质进样方法探讨

通过对不锈钢进样钢瓶两端进样方法的实验对比,研究了气相色谱法测定丙烯中微量烃类杂质时不同进样方法的优缺点.结果表明,进样钢瓶带不锈钢软管一端向下进样是最佳进样方法,所得数据精密度较高、重复性好.     

二氧化硅微粉对含矿化剂的石英粉鳞石英化的影响

在含矿化剂铁鳞和石灰的石英粉中分别添加6种不同纯度和粒度的二氧化硅微粉,经成型和1 400℃8 h煅烧后,进行物相组成和显微结构分析,研究了二氧化硅微粉对石英粉鳞石英化的影响。结果表明:1)添加二氧化硅微粉能够促进石英粉在煅烧过程中的鳞石英化及鳞石英晶体的发育;2)二氧化硅微粉纯度越低,粒度越小,其促进石英粉鳞石英化及鳞石英晶体发育的效果越显著。     

绞车滚筒轴密封结构改进

针对绞车滚筒轴漏油问题,分析了传统密封结构的缺点,设计了结构简单、无机械磨损、经久耐用的新型迷宫式机械密封结构。现场使用表明,密封性能可靠,能够有效解决绞车滚筒轴漏油问题,使钻井作业满足HSE要求。     

国内外牛肉相关法规标准研究进展

牛肉是我国消费需求量逐渐增加的食品之一,食品安全是消费者始终关注的焦点,而法规标准是确保食品安全的有力措施。本文通过国内外法规标准发布官方网站、监管机构门户网站等渠道,收集、编译和综述了2015年来国内外牛肉相关法律法规以及标准制定、修订工作的进展,主要涉及牛肉产品规范、等级、限量、检验、标签、进出口等六方面,同时,分析了当前国内外法规标准制定、修订特点,论述了我国牛肉法规标准体系现状、发展方向并提出建议,以期为完善我国牛肉法规标准、规范牛肉行业生产和保障进出口提供参考依据。     

利福平/磷酸八钙骨水泥载药体系的制备及体外释放特性

为了研究磷酸八钙骨水泥(cotacalcium phosphate,OCP)作为药物载体的体外释药行为,以利福平(rifampicin,RFP)作为模型药物,制备利福平/酸八钙骨水泥药物缓释体系.通过X射线衍射、红外光谱、场发射扫描电镜分析、万能电子试验机及紫外-可见分光光度计等测试方法,研究RFP对OCP的相组成、抗...     

Preparation and properties of 4, 4′‐diphenylmethane diisocyanate blocking modified poly(propylene carbonate)

Poly(propylene carbonate) (PPC) is inferior in thermal stability and liable to incur thermal degradation, especially in the existence of residual bimetal catalyst. In this article, PPC containing residual catalyst was end‐capped with 4, 4′‐diphenylmethane diisocyanate (MDI) through melt compounding. The blends were characterized by infrared spectra, melt flow index (MFI), gel permeation chromatography (GPC), gel content measurement, thermogravimetric analysis, scanning electron microscopy, and tensile test. The effect of MDI on thermal stability, molecular weight, and tensile properties of PPC was studied. Thermal degradation kinetics of neat PPC and PPC+MDI blending samples was discussed with Friedman method. MFI, GPC, and gel content measurements showed that mainly end‐capping reaction was carried out on PPC chains when 0.1% of MDI was added. However, as the amount of MDI exceeded to 0.3%, end‐capping, chain‐extension, and crosslinking reactions were synchronously carried out on PPC. Results showed that the end‐capping, chain‐extension, and crosslinking reaction occurring between PPC and MDI could effectively inhibit the unzipping degradation even when the residual catalyst was not removed thoroughly. When the content of MDI reached 1.0%, the initial degradation temperatures (T_‐5%) increased from 176.26°C for neat PPC to 259.56°C. As a result, the processing temperature range and processing time were largely extended, and the heat resistance of PPC was improved remarkably. Meanwhile, the tensile property of the modified PPC was enhanced obviously. It may be due to the fact that the molecular weight and gel content of PPC were increased with the increasing amount of MDI. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Enantioselective Synthesis of Unsymmetrical Diaryl‐Substituted Spirocyclohexanonepyrazolones through a Cascade [4+2] Double Michael Addition

The spirocyclic pyrazolones are an important class of molecular structures with significant biological and pharmaceutical activities. Herein, we demonstrate that the combination of a Cinchona‐based chiral primary amine and an ortho‐fluorobenzoic acid is an efficient catalyst system for the double Michael addition of arylidenepyrazolones with α,β‐unsaturated ketones, providing chiral unsymmetrical 6,10‐diaryl‐substituted spiro[cyclohexanone‐pyrazolone] derivatives in high yields (up to 98%) with good diastereoselectivities and excellent enantioselectivities (up to 88:12 dr, 99% ee).     

塑料在汽车工业中的应用

简述了塑料在汽车工业中的发展进程与我国现状。从塑料的品种、用量等方面介绍了其在汽车工业中的应用     

烟尘粉尘向大气排放的激光监测技术研究

提出了能直接测量烟尘和粉尘排放浓度和粒径大小的激光监测技术 ,具有实时快速、非接触、在线、无需取样和连续测量的优点。实验研究表明了该项技术的工作原理是正确的 ,测量结果是准确可靠的