油基钻井液的推广及循环利用

针对普通水基钻井液在钻进中强、强水敏性油藏时会造成储层污染、产量降低的问题,指出了油基钻井液在钻进该类油藏时的优势和其成本高、对生态环境有污染的缺点。为了大面积推广应用油基钻井液,重点介绍了油基钻井液的特性和稳定性影响因素,并通过室内评价证明了油基钻井液在油层保护中的良好效果,着重阐述了油基钻井液在王庄油田的现场应用情况,并探讨了油基钻井液的循环利用技术。研究结果表明,油基钻井液不仅具有良好的油层保护效果,而且具有较好的社会经济效益。     

Effect of the absence of lipoxygenase isoenzymes on the storage characteristics of rice grains

Three varieties of paddy rice with and three varieties without lipoxygenase (LOX) isoenzymes were stored at room temperature, in dark conditions for 42 months. Insect damage and viability were investigated during that time. Varieties without LOX-1,2 and their offspring were screened with a rapid method of estimating LOX isoenzymes, and subjected to an accelerated-ageing experiment. The results indicated that in varieties without LOX-1,2, after long storage, rice quality was normal, but for varieties with LOX-1,2, rice quality deteriorated. With increase of storage time, the germination rate of the seed of most varieties decreased greatly except for varieties without LOX-1,2 where there was almost no change in the germination rate. In varieties without LOX-1,2 and their offspring, after an accelerated ageing experiment the germination rate of some varieties changed slowly, but with others, the germination rate changed quickly. This indicated that a definitive factor, which influenced the life of seeds, may be the loss of LOX-1,2. During storage, there was also a significant difference in the degree of insect damage. In varieties without LOX-3 insect damage was lower, but in varieties with LOX-3 insect damage was higher. Therefore, the absence of LOX-3 may be very important in insect resistance in rice grain.     

WF40防腐蚀涂料在原料水罐上的应用

中国石化股份有限公司洛阳分公司炼油厂污水汽提装置的原料水罐(V303)由于接触的污水中含有H2S,NH3,CO2,CN-,酚等多种腐蚀介质因此经常发生腐蚀泄漏事故。经涂刷WF40玻璃鳞片防腐蚀涂料后,已平稳运行两年。2002年检修检查,涂层完好,仍在继续使用。WF40涂料为环氧型玻璃鳞片涂料,其热膨胀系数与钢质基体接近,因此具有耐热冲击性强等优点。待涂罐体经喷砂除锈到Sa2.5级后,涂底漆2道,中间涂层2道、面漆2道,使干膜厚度达到350μm,可有效防止腐蚀性介质的渗透。     

风水联动放炮自动喷雾装置设计

矿尘始终是困扰井下安全生产的重要因素之一，危害很大。长期从事采掘和粉尘作业环境的职工易引起尘肺病，另外，在粉尘作业场所工作的职工的视线易受阻挡，操作中易造成人身事故。     

砌筑砂浆达不到设计要求的事故原因分析

从砂浆的配合比、和易性、原材料等对砌筑砂浆达不到设计要求的事故原因进行了分析。     

One‐step production of 2,3‐butanediol from starch by secretory over‐expression of amylase in Klebsiella pneumoniae

BACKGROUND: 2,3‐Butanediol (2,3‐BD) is a valuable chemical that can be biosynthesized from many kinds of substrates. For commercial biological production of 2,3‐BD, it is desirable to use cheap substrate without pretreatment, such as starch. However, there have been few reports on the production of 2,3‐BD directly from starch. RESULTS: In this work, gene malS coding for α‐amylase (EC 3.2.1.1) precursor was inserted into plasmid pUC18K, and secretory over‐expression of α‐amylase was achieved by engineered Klebsiella pneumoniae. The extracellular recombinant amylase accelerated the hydrolyzation of starch, and one‐step production of 2,3‐BD from starch was carried out by engineered K. pneumoniae. A 2,3‐BD concentration of 3.8 g L^?1 and yield of 0.19 g 2,3‐BD g^?1 starch were obtained after 24 h fermentation. CONCLUSION: The one‐step production of 2,3‐BD from starch was achieved by secretory over‐expression of amylase in K. pneumoniae. This would simplify the process and reduce the production cost considerably by enabling use of starch with minimal pretreatment. Copyright © 2008 Society of Chemical Industry     

基于遗传算法的工作辊温度场参数优化模型

针对热连轧机工作辊热辊形计算中温度场模型的热交换等参数难以确定的问题 ,建立了基于遗传算法的参数优化模型 ,可以解决复杂条件下的热参数的求解问题。利用优化参数计算的轧辊温度场与实际测量结果一致。     

Flame retardant and the degradation mechanism of high impact polystyrene/Fe-montmorillonite nanocomposites

High impact polystyrene/Fe-montmorillonite (HIPS/Fe-MMT) nanocomposites were successfully prepared by melting intercalation. The nanostructures of HIPS/Fe-MMT were testified by X-ray diffraction (XRD) and transmission electron microscope (TEM). Corresponding to pure HIPS, the thermal stability of HIPS/Fe-MMT nanocomposites was notably improved. The peaks of heat release rate (PHRR) and the mass loss rate (MLR) were significantly reduced after the formation of the HIPS/Fe-MMT nanocomposites from cone calorimetry. And nanocomposites PHRR was further lower with the increase of Fe-MMT content in the range of 1 to 5 wt%. The degradation mechanism of HIPS and HIPS/Fe-MMT nanocomposites was conducted by pyrolysis gas chromatography mass spectrometry (Py-GC-MS). And the reason of the enhancement of thermal stability maybe is that structural iron is the operative site for radical trapping in the Fe-MMT and the nanostructure enhances the interaction of the chains of the HIPS.     

对交通预测工作的几点看法

近来,随着一些重大工程的建成使用,提高了上海交通设施的服务能力,使交通格局发生了一些变化,交通状况也出现了新的特点。但同时也发现,有些新的交通设施的使用情况与规划设计存在着一定的差异。因此,有关部门开展了一些项目的后评估工作,以总结经验,并为今后工作提供依据。交