浅析酥性饼干与曲奇饼干的区别

为明确区分中国酥性饼干和美国曲奇饼干,本文就我国国家粮食局制定的《酥性饼干用小麦粉》标准（LS／T3206--1993）中规定的酥性饼干和美国谷物化学家协会制定的《曲奇粉的烘焙品质》标准（AACC10—50D和AACC10—52）中规定的曲奇饼干,分别从定义、实验室制作方法、原料的要求及两种饼干在品质特性上的差异进行了具体阐述。     

Photocatalytic degradation of aromatic pollutants: a pivotal role of conduction band electron in distribution of hydroxylated intermediates

The modulation of the yield distribution of intermediates formed in the photocatalytic degradation of organic pollutants is of extreme importance for the application of photocatalysis in environmental cleanup, as different intermediates usually exhibit distinct biological toxicity and secondary reactivity. In this paper, we report that the distribution of monohydroxylated intermediates (m-, p- and o-) formed during the photocatalytic oxidation of aromatic compounds changes with the variation of reaction conditions, such as O(2) partial pressure and substrate concentration. By detailed product analysis, theoretical calculation, and oxygen isotope labeling experiments, we show that these changes are due to the selective reduction of HO-adduct radicals (the precursors of hydroxylated intermediates) by conduction band electrons (e(cb)(-)) back to the original substrate, that is, p- and o-HO-adduct radicals are more susceptible to e(cb)(-) than the m- one. Our experiments give an example that, even under oxidative conditions, the yield distribution of isomeric intermediates can be modulated by e(cb)(-)-initiated reduction. This study also illustrates that the unique redox characteristics of photocatalysis, that is, both oxidation and reduction reactions take place on or near the surface of a single nanoparticle, can provide opportunities for the reaction control.     

Effect of fermented rice culture on the microbiological,biochemical and sensory characteristics of low‐salt douchi,a traditional Chinese fermented soybean condiment

A low‐salt (4% NaCl, w/w) douchi supplemented with different concentration of fermented rice culture (FRC) of 0%, 5%, 10%, 15% and 20% (v/w) was produced, and the effect of FRC on microbiology, biochemistry and sensory quantity was investigated. Results indicated that FRC had a significant effect on low‐salt douchi. Compared with the control (added 0% FRC), in the other treatments, the counts of yeast and lactic acid bacteria increased by about 50%, whereas the moulds decreased by about 30%; the pH reduction was close to 4.7; total acid increased to about 1.300 g per 100 g; reducing sugar maintained a decrease to 21.07 mg per g; amino nitrogen increased to about 0.900 g per 100 g, but not above the control (1.013 g per 100 g). In general terms, total free amino acid contents and three organic acids were higher in low‐salt products than four commercial products. Sensory evaluation of products supplemented with 10% and 15% FRC revealed better overall acceptability compared with other treatments and a commercial product.     

Modal纤维与金属纤维混纺纱的开发

为了纺制出符合防辐射面料要求的纱线,选用金属纤维与Modal混纺,采用金属条与Modal条预并后再与Modal条进一步混并的工艺;通过优化粗纱和细纱牵伸工艺;合理配置络筒速度和张力,使纺出的防辐射面料用纱符合使用要求。     

Microencapsulation of camellia oil to maintain thermal and oxidative stability with focus on protective mechanism

Camellia oil (CO) microcapsules were developed using chitosan–soybean protein isolate (CS-SPI) complexes as wall materials and transglutaminase (TGase) as the cross-linking agent. Results indicated that CO/SPI under the ratio of 1:2 exhibited the highest microencapsulation efficiency and yield, possessing the best encapsulation effect. Morphology observation showed that CO microcapsules were intact, compact and nearly spherical. The microencapsulated CO exhibited the improved thermal resistance and significantly lower peroxide values after 3 days storage, demonstrating that the produced microcapsule was a promising way to maintain the thermal and oxidative stability of camellia oil. It could be found evidence from FTIR, which indicated that covalent cross-linking and hydrogen bonding might be involved among wall materials, and physical interactions between the core and wall materials. Therefore, the produced CO microcapsules could be an effective way to protect camellia oil, which was helpful for improving the processing and storage qualities of camellia oil.     

Study of aroma compound formations and transformations during Jinxuan and Qingxin oolong tea processing

We characterised the formation and dynamic changes in the main aroma compounds produced during the manufacturing process of Jinxuan and Qingxin oolong tea. Thirty-five aroma compounds were investigated. Subsequent principal component and cluster analyses showed that the fresh leaves, spread leaves and rocked leaves of the two varieties of tea were distinguished from each other. Particularly, the aldehyde and ‘other’ compounds showed the highest correlation coefficients (0.71 and −0.70) among the principal. The heat map showed that the proportions of acetic acid, 3-methylbutanal and 2-methylbutanal significantly changed during the manufacturing process of the two tea varieties. The key amino acids (isoleucine, leucine, valine and aspartic acid) and enzymes (branched-chain amino acid aminotransferase, aspartate aminotransferase and acetaldehyde dehydrogenase) involved in the synthesis of 3-methylbutanal and 2-methylbutanal differed between the two varieties during manufacture. Our study reveals the characteristics of different varieties of oolong tea and their aroma formation after manufacture using the same process.     

液相色谱法测定皮革中烷基酚聚氧乙烯醚的研究

对液相色谱的流动相进行了研究,利用带二极管阵列的液相色谱仪对烷基酚聚氧乙烯醚进行定量测定,得到了该方法的检出限、线性范围和回收率。     

基于山梨醇酐单棕榈酸酯防雾膜制备与性能研究

为研究山梨醇酐单棕榈酸酯的防雾效果,以山梨醇酐单棕榈酸酯为主要防雾材料,通过造粒得到防雾母料,三层吹塑共挤得到防雾聚烯烃薄膜,并对防雾母料造粒加工性能、薄膜防雾性能、光学性能、力学性能进行测试。结果表明,随着防雾剂在母料中含量的增加,母料熔点降低,融熔指数提高,流动性得到提升,利于母料的加工;当防雾剂在薄膜中含量为时,水滴在薄膜表面接触角为9.72°,薄膜的防雾等级在水浴热雾与急速热雾法测试条件下可到达1级;防雾剂含量在薄膜中含量为1.5%高温测试环境下的持久性达到168 h;随着防雾剂含量继续增加,薄膜的力学性能与光学性能均不同程度的下降,防雾剂在薄膜中的含量在达到防雾要求时应控制在适当水平。     

润版液的作用与使用

<正>胶印是利用润版液在一定印刷条件下水油相斥和水油相混乳化的双重作用来实现印刷的。润版液并非纯水,而是在水中加入了多种化学物质,配制成既能起润湿作用又能起清洗作用的弱酸液体。这种弱酸液体能与印版的空白部分生成一种亲水抗油的盐层,使印版印刷磨损的空白部分得到补充。同时,这种弱酸液体在着墨辊与印版频繁冲击挤压下,使水混入油墨中,形