塔北哈拉哈塘—英买力地区深层油气运移与成藏地球化学特征

采用地质、地球化学分析对哈拉哈塘—英买力地区油气特征、烃源灶部位、油气运移与成藏特征进行了反演研究。结果表明:原油物理与化学特征差异显著但有序分布,原油成熟度差异显著但成因相近。油-油、油-岩成熟度对比显示英买力地区原油与研究区埋深相近的泥灰岩没有可比性,哈拉哈塘地区深部奥陶系原油与埋深6 500~7 500 m的烃源岩成熟度相当,指示烃源灶为相邻凹陷。油气运移与成藏具有:1准差异聚集特征,从斜坡低部位至高部位,油气相态从轻质油—中质油—稠油呈规律性分布;2断层控制油气运移与聚集,油气主要聚集在断层附近,烃类流体性质、储层质量显著受控于断层,高气/油比油气主要出现在断层泄压区;3风化壳显著控制油气聚集与分布,油气主要分布在准层状风化壳上、下的岩溶储层内,具有多期充注成藏特征;4油气成藏模式为异地源-断控运移-准差异聚集-风化壳储油-多期叠加成藏模式。     

基于自适应采样算法的芳烃异构化代理模型

异构化是芳烃生产中的重要环节，提高异构化环节的建模和优化效率对工业生产有着重要意义。但是，直接使用机理模型的优化过程耗时较长，优化效率低。代理模型可以有效地对机理模型进行近似，而代理模型采样方法对模型精度有很大影响。提出了一种新的基于稀疏度和最邻近期望的自适应采样算法，该方法可以平衡全局搜索和局部搜索，通过求解优化问题找到反映函数关键信息的新采样点，再加入原始样本集中，使得代理模型精度不断提高。多个测试函数结果表明，相比于其他自适应采样算法，该算法能有效提升代理模型精度和建模效率。该算法在芳烃异构化环节代理模型中也得到了有效验证，与本文中其他算法对比，该算法模型误差减少5%以上，建模时间缩短30%以上。     

Steam-assisted roasting inhibits formation of heterocyclic aromatic amines and alters volatile flavour profile of beef steak

In order to evaluate the effect of steam addition during meat roasting, beef sirloin steaks were cooked at five humidities (0%, 25%, 50%, 75% and 100%) under 230 °C to a centre temperature of 71 °C. With increased humidity, heating rate generally increased and the cooked steak gradually lost the typical roasted appearance. Thiobarbituric acid-reactive substances (TBARS) values generally increased, while carbonyl groups were not affected. Increased humidity promoted the formation of volatile aldehydes and alcohols, while pyrazines decreased significantly from 0% to 25% humidity. Steam-assisted roasting inhibited the formation of heterocyclic aromatic amines (HAAs; except for IQ and Norharman). However, further increase in humidity (larger than 25%) did not have additional inhibition effect. Based on the results, it is recommended to roast beef with steam addition to reduce toxic HAAs, but the humidity should be kept at a relatively low level to maintain a typical roasted appearance and flavour profile.     

Vicious cycle during chemical degradation of sulfonated aromatic proton exchange membranes in the fuel cell application

Weak phase separation and vulnerable linking groups between aromatic units are common setbacks of sulfonated aromatic proton exchange membranes (PEMs) from durability point of view. In this study, sulfonated poly(ether ether ketone) (SPEEK) membranes were exposed to Fenton's solution for a specific time, ranging from 10 to 60 minutes. Chemical structure and morphology evolution, decay in mechanical and thermal stability, and H₂ permeability of SPEEK membranes were evaluated during the chemical degradation. Less-entangled polymeric chains with lower average molecular weight of degraded SPEEK samples diminished mechanical rigidity. In addition, reduction of aromatic rings in each repeat unit led to higher thermal decomposition rate. Furthermore, randomly distributed micro-defects in the SPEEK morphology and an increase in water sorption can reduce the fatigue strength of membranes in the wet-dry cycles. Eventually, hydrogen cross-over rate was gradually increased, and henceforth, accelerated destructive radical formation and degradation can be predicted.     

缩合多环多核芳烃树脂固化机理及固化树脂的热稳定性

In order to improve the thermal stability of condensed polynuclear aromatic(COPNA) resin synthesized from vacuum residue, 1,4-benzenedimethanol was added to cure COPNA resin. The curing mechanism was investigated by proton nuclear magnetic resonance spectrometry, solid carbon-13 nuclear magnetic resonance spectrometry and Fourier transform infrared spectroscopy. Microstructures of the uncured and the cured COPNA resins were studied by scanning electron microscopy and X-ray diffractometry. The thermal stability of COPNA resins before and after curing was tested by thermogravimetric analysis. The element composition of the cured COPNA resin heated at different temperatures was analyzed by an element analyzer. The results showed that the uncured COPNA resin reacted with the cross-linking agent during the curing process, and the curing mechanism was confirmed to be the electrophilic substitution reaction. Compared with the uncured COPNA resin, the cured COPNA resin had a smooth surface, well-ordered and streamlined sheet structure with more crystalline solids, better molecular arrangement and orientation. The weight loss process of the uncured and cured COPNA resins was divided into three stages. Carbon residue of the cured COPNA resin was 41.65% at 600 ℃, which was much higher than 25.02% of the uncured COPNA resin, which indicated that the cured COPNA resin had higher thermal stability.     

脂质氧化对肉制品中4 类有害物质形成影响的研究进展

肉制品加工过程中往往伴随着脂质氧化的发生，现有研究表明，脂质氧化能影响肉制品中杂环胺、N-亚硝基化合物、晚期糖基化终末产物及多环芳烃等有害物质的生成，这些物质的积累会降低肉制品的食用安全性并危害人体健康。本文综述了肉制品中脂质氧化的机制及氧化产物的反应活性、脂质氧化对肉制品中上述4 类有害物质形成的影响及相关控制措施，以期从控制脂质氧化的角度出发为肉制品安全性生产工艺提供参考。     

Distributions of Polycyclic Aromatic Hydrocarbons and Phthalic Acid Esters in Gums and Soapstocks Obtained from Soybean Oil Refinery

Soybean oil gums and soapstocks are important by-products that may potentially be contaminated by persistent organic pollutants (POP) such as polycyclic aromatic hydrocarbons (PAH) and phthalic acid esters (PAE), thus lowering the value when using them as starting materials to produce animal feed additives, food industry ingredients, and pharmaceutical products. In the present work, PAH and PAE distributions in these two types of by-products were detected using solvent extraction–solid phase extraction purification coupled with gas chromatography–mass spectrometry. Total PAH and PAE amounts in the soapstocks were significantly higher than those in the gums, thus indicating that neutralization showed much higher removal efficiency than degumming in terms of PAH and PAE eliminations. Meanwhile, the results proved that the concentrations of these two kinds of contaminants in the soybean oil gums and soapstocks were much higher than those in the soybean oils, suggesting that further investigations were needed and that the contents of PAH and PAE in soybean oil refining by-products should be carefully monitored and regulated.     

稠环芳烃加氢裂化机理和催化剂研究进展

稠环芳烃(PAHs)是一种化学稳定性高、难降解的有机污染物,加氢裂化可将PAHs转化为轻质芳烃和链烃,被认为是PAHs转化的有效方式之一。介绍了国内外加氢裂化工艺的概况、PAHs(萘、蒽、菲等)加氢裂化反应网络及其多相催化反应机理,分析了活性金属、酸中心、活性金属与酸中心的相互作用及助剂对加氢裂化催化剂性能的影响。提出优化金属中心和酸性中心之间的协同作用,制备出高活性、高选择性和稳定性的加氢裂化催化剂是PAHs加氢裂化催化剂的发展趋势。     

α-溴化芳香酮合成方法的改进

在氧化铜存在的条件下,以单质溴为溴源,芳香酮可有效地转化成相应的α-溴代酮,所有产物结构都通过了核磁共振氢谱的表征。