不同方法提取鳗鲡病原茵DNA模板的差异分析

利用吸光值、琼脂糖电泳及PCR差异扩增等指标,对酚一氯仿法、水煮法、碱裂解法3种方法制备的鳗鲡病原菌DNA模板进行了差异分析．结果表明：1）不同方法提取的病原菌模板DNA的浓度、纯度及分子质量大小存在差异,但以这3种方法提取的病原菌DNA为模板,均能成功扩增到细菌16SrD．NA和外膜蛋白的保守序列．其中,酚一氯仿提取的模板DNA浓度较低、纯度较高;水煮法和碱裂解法提取的模板DNA浓度较高、纯度较低．2）电泳显示,3种方法获得的模板DNA扩增出的16SrDNA保守序列条带均一,没有显著差异,但在外膜蛋白保守序列的扩增中却因菌种和模板提取方法的不同而存在差异．     

超声吹脱处理氨氮废水工艺条件的试验研究

通过对高浓度氨氮废水的超声吹脱正交试验,确定了试验的最佳工艺条件:pH为11,吹脱时间为90 min,吹脱温度为40℃,超声波功率为80 W.在此最佳吹脱条件下,氨氮的去除率可以达到99%以上,吹脱后废水中的氨氮浓度小于100 mg/L.     

真空膜蒸馏用于脱除水中氨的传质性能研究

对真空膜蒸馏脱除水中氨过程总传质系数的计算式进行了理论推导,并以真空膜蒸馏实验考察了料液温度、料液浓度及pH值对总传质系数影响。实验结果表明,随料液温度和pH值的增加,总传质系数明显增大,但pH值升至11后,总传质系数的变化不再明显。在实验所涉及的范围内,料液浓度对总传质系数的影响不大。总传质系数理论计算值与实验测定值吻合较好。     

苯丙氨酸体系片段CDA及轨道相互作用

采用密度泛函理论中的B3LYP方法, 在3-21G基组水平上优化气相S型苯丙氨酸（S-Phe）手性对映体的几何构型, 计算Phe分子轨道波函数及片段轨道间的电荷分解分析(CDA), 并给出片段COOH,C₆H₅和NH₂形成过程中片段间的轨道相互作用图. 结果表明: 片段COOH,C₆H₅和NH₂基于CDA的ri项最大正值分别为r₁₉,r₁₇和r₁₅, 即分子轨道的形成导致占据片段轨道的电子向交叠区域转移; 片段COOH和NH₂基于CDA的ri项最大负值分别为r₄₄和r₃₅, 即分子轨道的形成导致片段间占据片段轨道的电子从交叠区域移走.     

热虹吸氨—油冷却器的应用

本文对热虹吸氨—油冷却器运行原理以及在某工地的运行情况进行了介绍,提出了几点技术措施。并针对该工程进行了热虹吸氨—油冷却器与传统的水冷式油冷却器的经济性对比分析,提出在今后的冷冻工程中应大力推广热虹吸氨—油冷却器的应用。     

Nitridation of chromium powder in ammonia atmosphere

CrN powder was synthesized by nitriding Cr metal in ammonia gas flow, and its chemical reaction mechanism and nitridation process were studied. Through thermodynamic calculations, the Cr-N-O predominance diagrams were constructed for different temperatures. Chromium nitride formed at 7002-1200℃ under relatively higher nitrogen and lower oxygen partial pressures. Phases in the products were then investigated using X-ray diffraction (XRD), and the Cr₂N content varied with reaction temperature and holding time. The results indicate that the Cr metal powder nitridation process can be explained by a diffusion model. Further, Cr₂N formed as an intermediate product because of an incomplete reaction, which was observed by high-resolution transmission electron microscopy (HRTEM). After nitriding at 1000℃ for 20 h, CrN powder with an average grain size of 63 nm was obtained, and the obtained sample was analyzed by using a scanning electron microscope (SEM).     

SDG-Based HAZOP and Fault Diagnosis Analysis to the Inversion of Synthetic Ammonia

This paper presents some practical applications of signed directed graphs (SDGs) to computeraided hazard and operability study (HAZOP) and fault diagnosis, based on an analysis of the SDG theory. The SDG is modeled for the inversion of synthetic ammonia, which is highly dangerous in process industry, and HAZOP and fault diagnosis based on the SDG model are presented. A new reasoning method, whereby inverse inference is combined with forward inference, is presented to implement SDG fault diagnosis based on a breadth-first algorithm with consistency rules. Compared with conventional inference engines, this new method can better avoid qualitative spuriousness and combination explosion, and can deal with unobservable nodes in SDGs more effectively. Experimental results show the validity and advantages of the new SDG method.     

The Gas Sensitivity of Polypyrrole Film Fabricated by in Situ Polymerization

1 Results Polypyrrole (PPy) is a typical conducting polymer with high conductivity and good stability,and has been widely used for detection of gases including ammonia and nitroxide[1].However the reversiblity and selectivity of the response to these gases are always not satisfying.In the paper,conductive PPy film was deposited on the interdigital electrode modified by one bilayer of poly(diallyldimethylammonium chloride) and poly(sodium styrenesulfonate),by in-situ polymerization with FeCl3 as oxidizin...     

等离子体氧化NO耦合湿式氨法同时脱硫脱硝试验研究

为提高燃煤烟气同时脱硫脱硝工艺中的脱硝效率,将等离子体氧化技术应用到湿式氨法脱硫工艺中,建立了等离子体氧化NO耦合湿式氨法的脱硫脱硝试验装置.考察了液气比、氨水浓度、烟气流量、烟气温度、NO初始浓度、SO2初始浓度等工艺参数对同时脱硫脱硝性能的影响.试验结果表明:提高液气比、增加氨水浓度、减少烟气流量、降低烟气温度、减小NO和SO2初始浓度都可以提高脱硝效率,而试验范围内工艺参数对脱硫效率的影响几乎可以忽略;当液气比为10 L/m3、氨水浓度为4 mol/L、烟气流量为10 m3/h、烟气温度为85℃、NO初始浓度为3.5×10-4、SO2初始浓度为1.0×10-3时,该试验装置的脱硫效率和脱硝效率分别为99.6%和69.4%.     

新型3-溴-1-(3-氯-2-吡啶)-1H-吡唑甲酰胺类化合物的合成

以2,3-二氯吡啶为起始原料经过肼解、与马来酸二乙酯成环、溴代、氧化、水解得到关键中间体3-溴-1-(3-氯-2-吡啶)-1H-吡唑甲-1-甲酸,然后再与二氯亚砜反应生成甲酰氯,最后与各种环氨作用得到最终化合物3-溴-1-(3-氯-2-吡啶)-1H-吡唑甲酰胺类化合物,并对最终化合物进行表征.