Structure and properties relationships of epoxy resins part 1: Crosslink density of cured resin: (I) model resins synthesis

Two model epoxy resin precursors based on the N-glycidyl derivatives of 4.4'-diaminodiphenylene methane (DDM) were prepared: N,N bis-(2,3-epoxypropyl)-N′,N″-dimethyl-4.4'-diaminodiphenylene methane (G2A); N.N′ bis-(2,3-epoxypropyl)-N,N′-dimethyl-4,4'-diaminodiphenylene methane (G2S). To prepare these, aniline or N-methyl aniline was reacted with epichlorohydrin, using acetic acid as catalyst. The products were coupled via acid-catalysed condensations in the presence of formaldehyde or with N,N-dimethylaminobenzyl alcohol. The coupled chlorohydrins formed were then dehydrochlorinated to form the desired product. All reactions were monitored and purifications of the crude products were effected by high pressure liquid chromatographic techniques. The products were characterised by proton and carbon-13 nuclear magnetic resonance, infrared and mass spectroscopy, elemental and titrametric analysis. Results were compared with those obtained for tetra-N-glycidyl-4,4'-diaminodiphenylene methane (TGDDM). All the data confirmed the structures of the model resins. These, together with TGDDM. will be used to prepare epoxy resin networks of controlled crosslink density and chemical homogeneity.     

金刚石优化钻进的新途径

选择了优化钻进的衡量参数（ｈ／ｐ）／ｑ，并以此多数对具体岩石优选了钻头，对具体岩石和钻头优选了合理的钻头每转进尺范围。     

A solid state Pomeranchuk refrigerator

Recently we have shown that YbInCu₄ and related compounds present a solid state Pomeranchuk effect. At their first order volume transition, a local moment phase coexist with a renormalized Fermi liquid in analogy with ³He at its melting curve. This structural transition can be affected by pressure and magnetic field. We show here that as in ³He the Pomeranchuk effect can be used to produce cooling. We discuss the efficiency and different ways of implementing the solid state Pomeranchuk refrigerator.     

攀钢HC轧机板形控制实践

介绍板形缺陷类型及产生的机理，主要针对攀枝花钢铁(集团)公司冷轧厂HC轧机在近几年板形控制中的实践经验进行分析总结。     

Development of a direct sampling method for verifying the cleanliness of equipment shared with peanut products

A direct sampling method was developed to verify the cleanliness of stainless steel equipment used to produce peanut products. The protocol consisted of sampling the product-contact area with two Critical Swab^® flat zapped-head foam swabs pre-moistened with 20 mM phosphate, pH 7.2 (PBS), mixing each swab in PBS for 1 h, and analyzing the extract for peanut residues. Quantitation of peanut residues was accomplished with a non-specific assay while SDS–PAGE was used to ensure the recovery of the allergen, Ara h 1. This sampling approach was able to recover 90–95% of the peanut proteins at sub-microgram levels and Ara h 1 at low nanogram levels directly from a stainless steel surface.     

呼图壁呼2井区气藏合理开发技术指标确定

对呼图壁呼2井区气藏的凝析气高压PVT实验数据进行拟合计算,确定了适合描述该气藏流体相态行为的流体组分特征参数;利用地质研究成果所确定的单井各层物性参数,结合构造形态和井位,建立了相应的三维地质模型;在完成了储量拟合以后,针对气藏生产历史数据进行历史拟合研究,取得了令人满意的拟合效果;为了论证呼图壁呼2井区气藏合理开发技术指标,从9个方面对该气藏未来的开发指标进行了数值模拟研究,主要结论是:该气藏现有7口采气井能满足生产任务要求,气藏按150×104m3/d产能设计是合理的,稳产年限从2003年1月算起为8年,到2020年天然气和凝析油的采出程度分别为70.7558%和44.1564%.     

The kinetics and mechanism of manganese sulfidation

The kinetics and mechanism of manganese sulfidation have been studied as a function of temperature (673–1373 K) and sulfur vapor pressure (10–10⁵ Pa). It has been found that the rate-determining step of h655/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0">-MnS scale growth is the outward diffusion of metal. In the high-temperature range (>1000 K) coarsegrain scale is formed, and manganese diffuses in the form of Mn²⁺ cations and electrons via doubly ionized cation vacancies and electron holes (volume diffusion). In the low-temperature range (<800K), on the other hand, a fine-grain scale is formed, and manganese diffuses mainly through grain boundaries, but also in the ionized form. Finally, in the intermediate-temperature range (800–1000 K) grain-boundary diffusion prevails in the initial period of the reaction, and volume diffusion predominates during the later stages, as a result of grain growth of the scale.     

Wine phenolics—analysis of low molecular weight components by high performance liquid chromatography

Low molecular weight phenolic compounds were separated by high performance liquid chromatography on hydrocarbon-bonded reverse phase packings, with a water-methanol elution gradient. Phenolic compounds were extracted from wine with ethyl acetate. A first extraction at pH 7 enabled isolation of neutral molecules (catechins, procyanidins, flavonols, aromatic alcohols); a second extraction at pH 2 was performed to extract phenolic acids. Successive injections of these two extracts in the chromatograph gave the distribution of the different phenolic compounds in the wine under analysis. Analytical data are given for low molecular weight phenolic compounds present in young red Bordeaux wines from different vine cultivars.     

A novel extraction method for peanut allergenic proteins in chocolate and their detection by a liposome-based lateral flow assay

In this study, conditions for extracting the major peanut allergen (Ara h1) from chocolate were optimized, and the extracted samples were analyzed by a lateral flow assay (LFA) using liposomal nanovesicles. The optimal conditions using peanut-spiked chocolate were found to be extraction with a mixture of phosphate buffered saline and hexane for 30 min at 35 °C. After centrifugation, the buffer portion was treated with insoluble poly(vinylpolypyrrolidone) to remove phenolic compounds, and then analyzed by the LFA. The entire analysis, including sample preparation and LFA, could be easily completed within 2 h, and the detection limit was 158 g of peanuts/g of chocolate.