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.     

学生心理健康与学校德育工作

通过结合学生实际行为表现，阐明心理健康教育与学校德育工作的关系，表明开展素质教育的今天，只有搞好心理健康教育，才能保证德育工作的顺利开展，实现素质教育的目标。     

650t/h桥式卸船机卷筒装置故障分析及其改进措施

综合分析了我单位650t/h桥式卸船机起升开闭减速机卷筒装置的结构特点,对出现的一些故障进行分析研究。采用新型联轴器,同时改进卷筒结构,并规范操作技能和加强点检定修等措施来提高卷筒装置的安全可靠性。     

掺烧高、焦炉煤气燃烧器设计体会

简要介绍了掺烧高、焦炉煤气燃烧器的设计要求 ,探讨了采用焦炉煤气点火、启动锅炉的问题和方法 ,肯定了栅格式高炉煤气喷嘴的效果     

Legumin allergens from peanuts and soybeans: effects of denaturation and aggregation on allergenicity

Legumin proteins Ara h 3 from peanuts and glycinin from soybeans are increasingly described as important allergens. The stability of an allergen's IgE binding capacity towards heating and digestion is considered an important characteristic for food allergens. We investigated the effects of heating and digestion on the IgE binding of Ara h 3 and glycinin. Both proteins are relatively stable to denaturation, having denaturation temperatures ranging from 70 to 92 degrees C, depending on their quaternary structure and the ionic strength. Aggregates were formed upon heating, which were partly soluble for glycinin. Heating slightly decreased the pepsin digestion rate of both allergens. However, heating did not affect the IgE binding capacity of the hydrolyzates, as after only 10 min of hydrolysis no IgE binding could be detected any more in all samples. Peanut allergen Ara h 1, when digested under equal conditions, still showed IgE binding after 2 h of hydrolysis. Our results indicate that the IgE binding capacity of legumin allergens from peanuts and soybeans does not withstand peptic digestion. Consequently, these allergens are likely unable to sensitize via the gastro-intestinal tract and cause systemic food allergy symptoms. These proteins might thus be less important allergens than was previously assumed.     

花生过敏原Ara h 1蛋白的原核表达及致敏性分析

从花生中提取总RNA,用反转录聚合酶链式反应得到花生过敏原Ara h 1基因,构建pET-28a-Ara h 1表达载体,转入Rosetta（DE3）宿主表达菌中诱导产物表达,用镍离子亲和层析法纯化得到目的蛋白。十二烷基硫酸钠-聚丙烯酰胺凝胶电泳结果显示目的蛋白分子质量约为75 kDa,与预计相符;经质谱鉴定为Ara h 1蛋白。用BALB/c小鼠模型评价重组Ara h 1蛋白的致敏性结果显示,重组Ara h 1蛋白致敏小鼠血清中特异性抗体、Th2型细胞因子、组胺含量升高,空肠和肺组织发生病变,表明重组Ara h 1蛋白可以导致小鼠发生Th2型过敏反应,且有与天然Ara h 1蛋白相似的致敏性。同时RBL细胞模型结果显示重组Ara h 1蛋白还可导致RBL细胞脱颗粒,释放β-己糖苷酶,进一步表明重组Ara h 1蛋白具有致敏性。     

Internal oxidation of Fe-Al alloys in the α-phase region

The internal oxidation behavior of Fe-0.069, 0.158, and 0.274 wt% Al alloys was investigated in the h146rt123v562472/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0">-phase region. The internal oxidation experiments have been made over the temperature range from 1023 to 1123 K using a mixture of iron and its oxide powders. A parabolic rate law holds in the present alloys, where the rate constant, K_p, depends upon the oxidation temperature as well as the aluminum content. The internal oxidation of Fe-Al alloys is, therefore, controlled by a diffusion process of oxygen in the alloy. The oxide formed in the oxidation layer is the stoichiometric FeAl₂O₄ (hercynite). The aluminum concentration, N _Al ^Io , in the oxidation layer was calculated by taking account of counterdiffusion of aluminum. Furthermore, the oxygen concentration, N _O ^S , at the specimen surface was evaluated on the basis of thermodynamics. Using these estimated values of K_p, N _Al ^IO , and N _O ^S , the diffusion coefficient of oxygen, D _O ^IO , in the oxidation layer, where the oxide particles were dispersed, was also calculated. D _O ^IO increases as the volume fraction of the oxide, f^IO, increases. The diffusion coefficient of oxygen, D_O, in h146rt123v562472/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0">-iron was determined by extrapolating D _O ^IO to f^IO=0.     

An extension of the Hertz theory for three-dimensional coated bodies

This paper presents a work on extending the Hertz theory for circular and elliptical point contact problems involving coated bodies. The extended form of the Hertzian formulae are adopted to express maximum contact pressure, contact radius, and contact approach in terms of applied load, equivalent radius, and an extended equivalent modulus that properly considers the presence of a coating. The extended equivalent modulus is a function of Youngh1163r6757480x64/xxlarge8217.gif" alt="rsquo" align="BASELINE" BORDER="0">s moduli and Poissonh1163r6757480x64/xxlarge8217.gif" alt="rsquo" align="BASELINE" BORDER="0">s ratios of the coating and the substrate, coating thickness, and a parameter, which is obtained through substantial numerical simulation. The extended Hertzian formulae are easy to use and give accurate predictions of contact characteristics.     

Effects of morphological control on the characteristics of vertical-type OTFTs using Alq3

We have fabricated vertical-type organic thin-film transistors (OTFTs) using tris-(8-hydroxyquinoline) aluminum (Alq(3)) as an n-type active material. Vertical-type OTFT using Alq(3) has a layered structure of Al(source electrode)/Alq(3)(active layer)/Al(gate electrode)/Alq(3)(active layer)/ITO glass(drain electrode). Alq(3) thin films containing various surface morphologies could be obtained by the control of evaporation rate and substrate temperature. The effects of the morphological control of Alq(3) thin layer on the grain size and the flatness of film surface were investigated. The characteristics of vertical-type OTFT significantly influenced the growth condition of Alq(3) layer.