广州市纸张批发价

(S/324一99)规格批发价(元/令)njn︸n甘0勺J7j..1 f.二‘.五1 051400 Lan︺一口产曰门︺5尸a八七尸了心n︸‘787 x 2092毫米75了xz092毫米78了x Ic92毫米75了xlo92毫米了s了xzo92毫米787 x 1092毫米78了xxo92毫米了盯xl092毫米了8了义一。92毫米79了x工。‘,毫米丁只了x 10:〕2毫米了8了只1092毫米了8了xlooZ毫米78了xlo92毫米7R了x1092毫米78了xl092毫米了87义2092毫米了8不xlo92毫米了8了xlooZ毫米了8了xl。。2毫米了盯丫1092毫米丁8了x 2092毫米1 45n gUU口n︺n以进人t了八U 9.)一了山..1,.占J..五...二品种书写纸co克书写纸8。克书…     

基于 ANSOFT 的电动汽车用永磁无刷直流电机参数优选设计

本文阐述了计算优选法的方法和原理;确定了设计变量与计算参数 ; 建立了电机模型;增加了设计变量;创建了 Setup 与添加了计算参数 ; 优选计算了一组设计方案;选择了一款满足电动汽车用永磁无刷直流电机方案;提高了设计效率。     

激情飞扬谱华章 理性调整蓄强势——中国眼镜行业2007年盘点

中国眼镜涨价了．隐形眼镜筑底反弹了,专业技术培训火爆了,交流合作频繁了,公益活动升温了,明星推广风行了……     

自己动手,丰衣足食

忽然之间,通胀了。超市里,米贵了,面贵了,油贵了,连卷纸都在涨。菜场里,青菜贵了,海鲜贵了,各种肉也贵了。一时之间,贵气袭来,席卷了我们的生活。我们的收入没变,但是能够换来的实物越来越少了。     

食品科学的最新发展：分子物理美食学

食品科学的最新发展：分子物理美食学菜是否熟了，是嫩了还是老了？作料是否合适，多了还是少了？火大了还是小了？时间是长了还是短了？这些素来仅能凭我们的感官和经验来回答的问题如今科学家们已在作出精密的答案——这就是分子物理美食学。菜炒嫩了和炒老了凭肉眼是难...     

贯彻落实《公告》精神，稳步推进绿色印刷

今天开了一个很有成效的绿色印刷技术交流会,总署和环保部两位领导对《公告》作了深入的解析,使我们进一步提高了认识,明确了目标、掌握了政策、增强了信心、鼓舞了斗志。     

涨时代的机遇与挑战

让价格再飞一会 盘点2010白酒行业的关键词,“涨”字无疑是最热门的话题：方便面涨价了,鸡蛋涨价了,面粉涨价了,燃油涨价了,蔬菜涨价了,食用油涨价了,棉花涨价了,水电费涨价了……很多人不禁感慨：“除了工资,身边的一切都涨了!”     

学会活动动态

今年初,广东省纺织工程学会理事会在肇庆召开了第四届第二次理事会扩大会议,会上传达了厅局长会议精神,通报了纺织“八五”发展计划和2000年发展规划,强调了学会工作在振兴纺织工业中的重要作用,并从思想上、组织上加强了学会工作的领导,重新设置了学术部和科普部。随后,各部健全了组织领导,明确了分工,制定了活动计划。科普部制定了     

褪去“奢侈”面纱平板放量增长

经历了关键一年的培育,平板电视终于脱颖而出,褪去了“奢侈品”的面纱,逐渐走入寻常百姓家,平板电视在2005年得到了放量的增长,销量达到了188万台,与2004年同期相比增长了379.3%,销售额达到了239亿元,比2004年增长了292.7%。中国平板电视终于结束了漫长的导入期,进入了快速成长     

自动木工机的方案设计与分析

在阐明新产品原理方案设计方法的基础上，设计了自动木工机。完成了木工机总功能的求解，得到了几种解决方案，进行了比较，优选出了其中的一种解决方案，并对其关键部件进行了可行性建模分析，制作出了产品模型，验证了方案的可行性。     

Exogenous Lipids and Ethanol Influences on the Foam Behavior of Sparkling Base Wines

The influence of added lipids (which mimic the endogeneous lipid pool of wine) on the foam behavior of sparkling base wines at various ethanol concentrations was investigated by measuring the foam expansion, foam stability and the Bikerman coefficient. Depending on their physical state, molecularly dissolved or aggregated, the lipids were only active at low alcohol concentration. At high alcochol content foam behavior was mainly governed by ethanol concentration. Bikerman coefficient variations were correlated with the surface tension variation.     

Qualitative and quantitative research of propyl lactate in brewed alcoholic beverages

Recently, propyl lactate has been firstly detected in Chinese Baijiu (Chinese liquor) as one of the odor-active components. In this study, the contents of propyl lactate in other different brewed alcoholic beverages were investigated, including wine, soju, sake, vodka, rum, tequila, whisky and beer, and analyzed by solid-phase microextraction and liquid–liquid extraction coupled with gas chromatography-mass spectrometry, determined by internal standard method followed by GC-MS with selective ion monitoring. The analyses indicated that propyl lactate was present in beer and tequila samples, while not detected in other brewed alcoholic beverages. The results showed that among the 40 beer samples from 11 different countries, 36 of them contained propyl lactate at concentrations in the range of 0.23–51.71 µg L^?1. In addition, all of six tequila samples contained propyl lactate at concentrations in the range of 0.77–12.14 mg L^?1, and the odor activity values (OAVs) of propyl lactate were greater than 1 in all of the tequila samples. These findings indicated that propyl lactate was widely distributed in beer and tequila; it was also an odor-active component of tequila according to OAVs.     

Inhibition of Saccharomyces cerevisiae by slow release of propyl paraben from a polymer coating

The inhibition of Saccharomyces cerevisiae by slow release of propyl paraben from a styrene-acrylate copolymer coating was examined and compared with the inhibition by direct addition of propyl paraben. Under slow release condition, a slow but continuous microbial inhibition was observed, whereas a cell outgrowth was observed under direct addition condition after a sufficient incubation time. S. cerevisiae cells isolated from the culture under direct addition condition were more tolerant of propyl paraben than cells isolated from the culture under slow release condition. The equilibrium propyl paraben concentrations under both conditions were 150 ppm. The release kinetics of propyl paraben from the coating at 30 degrees C was found to be controlled by Fickian diffusion within the coating. The estimated partition and diffusion coefficients were 4.65 x 10(-3) and 2.01 x 10(-10) cm2/s, respectively.     

Oxidation in fish-oil-enriched mayonnaise 1. Assessment of propyl gallate as an antioxidant by discriminant partial least squares regression analysis

 A number of different analytical techniques (HPLC, GC-MS, sensory analysis, laser diffraction droplet size determination, confocal laser scanning microscopy and rheological measurements) were employed to elucidate both chemical, sensory, structural and rheological aspects of the oxidation process in mayonnaise containing 16% fish oil. The primary focus of the study was on the antioxidative effect of two different types of commercial propyl gallate mixtures: an oil-soluble and a water-soluble preparation. The effect of adding extra emulsifier (Panodan TR), used to manipulate the physical structure of the fish-oil-enriched mayonnaise and in turn affect the antioxidative activity of the propyl gallate mixtures, was also investigated. Mayonnaise with fish oil did not oxidise faster than mayonnaise without fish oil when judged from the chemical parameters tested. However, the fish-oil-enriched mayonnaises developed unpleasant off-odours and off-flavours much faster than the mayonnaise without fish oil. Addition of the two different propyl gallate mixtures not only influenced negatively the sensory qualities but also affected the structure and the rheological properties of the mayonnaise. Propyl gallate thus, in particular, promoted the development of fishy and rancid off-flavours during the storage of mayonnaise with fish oil, and this effect was especially pronounced for the water-soluble propyl gallate mixture. Four volatile oxidation compounds, namely 3-furaldehyde, 2,4-heptadienal, 2,4-decadienal and ethyl benzene, appeared to correlate to the fishy and rancid off-flavours that developed in mayonnaises with propyl gallate. Addition of propyl gallate also resulted in increased peroxide values, and a less viscous mayonnaise with bigger droplets. The data thus demonstrated that the propyl gallate mixtures employed did not protect mayonnaise with fish oil against flavour deterioration due to oxidation during storage. In addition, the data showed that several structural and rheological parameters were affected by the addition of propyl gallate. Received: 16 November 1998     

基于顶空固相微萃取技术结合气相色谱质谱联 用法的川法小曲白酒挥发性成分研究

目的明确川法小曲白酒主体挥发性成分组成。方法应用顶空固相微萃取(HS-SPME)技术结合气相色谱质谱联用仪(GC-MS)分析技术分析川法小曲白酒主体挥发性成分组成。结果 4种不同地区川法小曲白酒(江津、永川、开江、自贡)中共检出64种挥发性成分,其中江津检出29种、永川31种、开江44种、自贡45种。4种不同产区酒中的共有物质为乙酸乙酯、正丙醇、异戊醇、癸酸乙酯等15种成分。主成分分析结果显示正丙醇、异戊醇、乙酸乙酯、乙酸异戊酯、癸酸乙酯、乳酸乙酯等15种成分在挥发性成分体系中贡献率较大。定量结果显示,4种不同地区川法小曲酒中的乙酸乙酯含量为0.4170~2.0880 g/L;乳酸乙酯含量为0.1115~0.2809 g/L;正丙醇含量为0.5416~0.9729 g/L;异丁醇含量0.3327~0.6371 g/L;异戊醇含量为0.7721~1.1701 g/L。结论 4种样品酒中异戊醇与正丙醇的比值分别为:1.0、1.2、1.1、1.5,异戊醇与异丁醇的比值分别为2.5、1.8、2.2、2.4,可作为川法小曲白酒特有的标志。     

大葱挥发油含量与化学成分的分析

采用水蒸气蒸馏法提取莱芜鸡腿葱中的挥发油 ,测知其含量为 0 0 1 % ;并用毛细管气相色谱 /质谱法定性鉴别了挥发油中的 2 5种化学成分。其中含硫有机硫化合物为 2 0种 ;主要成分有 :丙基甲基硫代硫磺酸酯 ,甲基烯丙基硫代硫磺酸酯 ,甲基丙烯基三硫醚 ,烯丙基硫醇 ,甲丙基二硫醚 ,反式甲基烯丙基二硫醚 ,二甲基三硫醚 ,二丙基二硫醚 ,反式烯丙基丙基二硫醚 ,二甲基四硫醚 ,二丙基三硫醚 ,反式烯丙基丙基三硫醚 ,顺式烯丙基丙基三硫醚 ,甲硫醇 ,丙硫醇 ,二巯基甲烷 ,2 ,5 二甲基噻吩等含硫化合物 ,还鉴定出不饱和脂肪醛 1种 (3 ,7 二甲基 2 ,6 二辛烯醛 ) ,脂肪酮 1种 (十一酮 2 ) ,萜烯类化合物 2种 (2 甲基 庚稀 2和顺式 2 ,6 二甲基 2 ,6 辛二烯 ) ,挥发性无机化合物 1种 (SO2 )。     

Preservation of the endogenous antioxidant system of fish muscle by grape polyphenols during frozen storage

The capacity of a phenolic extract, OW, obtained from grape (Vitis vinifera) by-products, and of a purified fraction of procyanidins from OW, fraction IV, for preservation of endogenous antioxidants of fatty fish was investigated during frozen storage. They were used in muscle concentrations of 0.01% (w/w). Grape polyphenols were compared with propyl gallate, a synthetic antioxidant. The exogenous compounds were added to minced mackerel (Scomber scombrus) muscle and horse mackerel (Trauchurus trauchurus) fillets, before freezing at –10 °C. The results demonstrated that grape polyphenols and propyl gallate inhibit the depletion of endogenous -tocopherol, ubiquinone-10 and total glutathione. Grape polyphenols and propyl gallate showed similar efficiency for preservation of ubiquinone, in both minced and filleted muscle, and total glutathione, in minced muscle. Total glutathione in the fillets was better maintained by propyl gallate than grape polyphenols. The endogenous antioxidant more efficiently preserved by grape polyphenols and propyl gallate was -tocopherol. Its loss elapsed faster in the order control> OW>fraction IV>propyl gallate. The depletion of -tocopherol was highly correlated with the evolution of lipid oxidation. The development of lipid oxidation was repressed, while the concentration of -tocopherol was not reduced up to critical levels.     

去除正丙醇提高糖蜜酒精质量

新的食用酒精质量标准将正丙醇作为一项质量指标来考查。正丙醇属中级杂质，与水、乙醇混溶，沸点较接近乙醇，分离难度较大。应从多方面着手，控制正丙醇含量：1．使用产正丙醇少的酵母菌种。2．发酵液的组成要合理。3．防止杂菌感染。4．强化杂醇油提取工作。5．在醛塔的顶部加水。增加精馏塔精馏段塔板数。(丹妮)     

Effects of Antioxidants on Growth, Sporulation and Pseudomycelium Production by Saccharomyces cerevisiae

Butylated hydroxyanisole (BHA), tertiary butylhydroquinone (TBHQ) and propyl gallate were evaluated for their effects on growth, sporulation and pseudomycelium production by Saccharomyces cerevisiae. As little as 150 ppm BHA, 300 ppm TBHQ and 3000 ppm propyl gallate significantly (P 0.05) reduced the number of colonies formed on agar media compared with controls. The rate of growth was adversely affected by as little as 50 ppm BHA, 100 ppm TBHQ and 500 ppm propyl gallate. At pH 3 and 7, there was a combined inhibitory effect with antioxidants on the rate of growth compared to effects at pH 4–6. BHA and TBHQ increased the time required for sporulation. Production of pseudomycelium was affected by propyl gallate when the yeast was grown on corn meal agar. None of the antioxidants was as effective in a model food system (ice cream mix) containing 2% oil as they were in laboratory media.     

Effect of the Parabens With and Without Nitrite on Clostridium botulinum and Toxin Production in Canned Pork Slurry

Antimiciobials were evaluated in thioglycollate broth at pH 6.5 for the ability to inhibit growth and toxin production by C. botulinum 12885A and ATCC 7949 (Type B). Methyl, ethyl, propyl, and butyl parabens (0.1%) and sorbic acid (0.2%) were effective in inhibiting growth of C. botulinum 12885A and ATCC 7949 in broth. Ethyl, propyl, and butyl parabens (0.1%) and sorbic acid (0.2%) inhibited toxin production by both strains in culture medium. Ethyl, propyl, butyl parabens (0.1%) and sorbic acid (0.2%) were individually added to a comminuted pork slurry having salt and sugar, with or without 40 ppm sodium nitrite. Cans were inoculated with a mixture of C. botulinum 12885A and ATCC 7949 spores. The canned product was abused by holding at 27°C and was observed over a 3-month period for swollen cans. Swollen cans were examined for botulinal toxin by the mouse bioassay. Propyl and butyl paraben did not inhibit or delay toxin production. Ethyl paraben with or without nitrite delayed toxin production for 4 wk. Sorbic acid inhibited toxin for 3 wk; when 40 ppm nitrite was added to the sorbic acid treatment, toxin production was delayed for 4 wk.