水性聚氨酯的制备

要制得性能优良的木器用水性聚氨酯乳液,要从制备水性聚氨酯用的原料聚酯二元醇入手,文章设计分子量为1000的聚酯二元醇,它使用邻苯二甲酸酐和己二酸以摩尔比40∶60混合后再与乙二醇反应,制得的水性聚氨酯乳液,其化学稳定性、涂膜硬度,相对于单独用脂肪族聚酯二元醇制备的水性聚氨酯的性能要优。     

国内外聚醚多元醇开发进展

评述了聚醚多元醇的生产技术与产品开发进展,以及世界和中国的聚醚多元醇市场分析,并提出了发展建议。     

Effect of support type and synthesis conditions on the oxygen reduction activity of RuxSey catalyst prepared by the microwave polyol method

Ru_xSe_y nanoparticles supported on different carbon substrates were synthesized by microwave heating of ethylene glycol solutions of Ru(III) chloride and sodium selenite at different pH and Ru/Se mole ratios. The resulting catalysts were used for the electrochemical oxygen reduction reaction (ORR) in acidic solution. The electrochemical activity was highest for the supported catalyst synthesized at pH 8. Increasing the Se concentration of the catalyst up to 15 mol% increased the catalytic activity for the ORR; at this Se concentration, the activity of the catalyst was considerably higher than that observed for pure Ru catalyst synthesized at exactly the same conditions. The influence of the type of carbon support on the activity of the electrocatalyst was also investigated. Among the different supports, including carbon black (Vulcan XC-72R) (C1), and nanoporous carbons synthesized from resorcinol- (C2) and phloroglucinol-formaldehyde (C3) resins, the Ru_xSe_y catalyst supported on C3 exhibited highest activity for ORR.     

用于可焊性漆包线漆的聚酯多元醇的合成及性能测定

发展了一种聚酯多元醇,可望应用于制备新型的直焊性耐热漆包线漆。采用间苯二甲酸、己二酸、乙醇胺或乙二醇、三乙醇胺或甘油,通过熔融共缩聚合成一系列聚酯多元醇,然后用甲醚化氨基树脂及溶剂混合、配制成溶液,再涂制成漆包线。研究结果表明系列聚酯多元醇的分子量、酸值均符合漆包线漆制备的技术要求;采用乙醇胺代替乙二醇、三乙醇胺代替甘油在聚酯多元醇的合成反应中具有较高的缩聚反应活性,由此制备的聚酯多元醇具有在350℃至400℃的范围内更快速分解和分解残渣较少的特点,采用此聚酯多元醇作为主要成分、涂制的漆包线在400℃至460℃范围内下可直焊,介质损耗曲线的拐点温度可达到162℃、意味着耐热等级较高。     

折叠带蒂髂腹股沟皮瓣修复手掌洞穿性缺损的围手术期护理

目的探讨带蒂髂腹股沟皮瓣折叠修复手掌洞穿性缺损的围手术期护理。方法2004～2008年,12例手掌洞穿性缺损应用带蒂髂腹股沟皮瓣折叠修复,采取心理护理、皮瓣受区、皮瓣供区准备、皮瓣血运监测、皮瓣固定护理、体位护理、饮食控制等围手术期护理。结果皮瓣全部成活,康复顺利,无并发症发生。结论该围手术期系统护理策略对带蒂髂腹股沟皮瓣折叠修复方法修复手掌洞穿性缺护理是安全有效的护理方法。     

棕榈藤材的制备和加工

对藤材制备的采收、油浴、漂白等初加工工艺和藤材制品生产的精加工工艺进行了系统论述,分析了国内外藤材工业的发展现状和目前藤材工业面临的主要问题,指出藤材的基础研究有待进一步加强,以便更好地开发利用藤材,提高藤材利用率和藤制品价值.     

基于维生素E组成的植物油掺棕榈油鉴别研究

目的 建立基于维生素E组成的植物油掺棕榈油鉴别方法。方法 采用正相高效液相色谱-荧光检测方法测定大豆油、菜籽油、葵花籽油、橄榄油、玉米油、棕榈油等植物油中α-、β-、γ-、δ-生育酚和α-、β-、γ-、δ-生育三烯酚8种维生素E组成,使用主成分分析（principal component analysis, PCA）构建植物油品种识别和掺假油鉴别模型。结果 不同种类植物油中的生育酚和生育三烯酚的组成差异很大,棕榈油中含高水平的生育三烯酚,这成为其区别于其他5种植物油的一个重要特点。结合PCA可以将棕榈油、葵花籽油、大豆油、橄榄油等相互区分开来。采用PCA建立了针对菜籽油、大豆油、橄榄油、葵花籽油、玉米油中掺棕榈油的鉴别模型,当棕榈油掺杂浓度大于等于25%时,模型可准确识别出掺假油。结论 采用正相液相色谱-荧光检测方法测定植物油中α-、β-、γ-、δ-生育酚和α-、β-、γ-、δ-生育三烯酚8种维生素E组成,结合化学计量学法,可实现对常见植物油掺棕榈油的鉴别。     

UASB工艺处理聚酯多元醇废水的研究

采用高负荷UASB工艺处理聚酯多元醇废水,分析了UASB有机负荷对CODCr去除率影响及其进水、出水pH的变化。研究表明,在中温(37±2℃)环境下,UASB有机负荷7 kg/(m3.d)时,CODCr去除率在85%以上,运行稳定。     

Comparison of the stability of palm olein and a palm olein/canola oil blend during deep‐fat frying of chicken nuggets and French fries

Stability of palm olein (PO) and a blend 50% palm olein/50% canola oil (POC) during deep‐fat frying at 180 °C of French fries (FF) or chicken nuggets (CN) was studied through the determination of physical and chemical parameters in the fresh and used oils. Degradation at the end of the study resulted in total polar compounds of 12–13.5% for PO and 11.5–14.5% for POC and viscosity of 65–123.3 cP for PO and 63–72.8 cP for POC. Lower peroxide values (5.33–6.32) were obtained for the blend (PO had 5.21–8.55). Food type affected colour parameters and p‐anisidine value of the oils. For CN, the lowest fat content and higher hardness were obtained when they were fried in PO. CN caused a faster deterioration in the oils, in comparison with FF, especially in POC. Gas chromatography allowed to observe differences in fatty acids composition for both used oils.     

Effectiveness of antioxidants in preventing oxidation of palm oil enriched with heme iron: A model for iron fortification in baked products

Bakery products such as biscuits, cookies, and pastries represent a good medium for iron fortification in food products, since they are consumed by a large proportion of the population at risk of developing iron deficiency anemia, mainly children. The drawback, however, is that iron fortification can promote oxidation. To assess the extent of this, palm oil added with heme iron and different antioxidants was used as a model for evaluating the oxidative stability of some bakery products, such as baked goods containing chocolate. The palm oil samples were heated at 220°C for 10 min to mimic the conditions found during a typical baking processing. The selected antioxidants were a free radical scavenger (tocopherol extract (TE), 0 and 500 mg/kg), an oxygen scavenger (ascorbyl palmitate (AP), 0 and 500 mg/kg), and a chelating agent (citric acid (CA), 0 and 300 mg/kg). These antioxidants were combined using a factorial design and were compared to a control sample, which was not supplemented with antioxidants. Primary (peroxide value and lipid hydroperoxide content) and secondary oxidation parameters (p‐anisidine value, p‐AnV) were monitored over a period of 200 days in storage at room temperature. The combination of AP and CA was the most effective treatment in delaying the onset of oxidation. TE was not effective in preventing oxidation. The p‐AnV did not increase during the storage period, indicating that this oxidation marker was not suitable for monitoring oxidation in this model.