碳纤维表面特性及其在水中的分散性

对碳纤维的表面形貌、表面基团和表面电荷进行了分析,并就碳纤维长度、分散条件、分散剂种类和用量对碳纤维在水中分散性的影响进行了研究.结果表明,所用碳纤维表面粗糙,带有羟基、羰基等活性基团,表面负电荷密度约为20.3μmol/g;搅拌器打散碳纤维能提高其在水中的分散性,搅拌器内理想的浆液浓度为0.07%;加入APAM分散剂能改善分散,APAM适宜添加量为0.6%～0.8%.     

分散剂对聚酰亚胺纤维纸性能的影响研究

实验以PEO、吐温-80、MOA-9为分散剂,研究了分散剂种类及其用量对聚酰亚胺(PI)纤维分散能力及对PI纤维纸物理性能的影响。结果表明:添加单一分散剂时,PEO分散效果最好,当PEO用量为0.06%时,PI纤维纸物理性能最佳;添加混合分散剂比单一分散剂的分散效果好,且PEO和MOA-9混合分散效果最好,当PEO与MOA-9用量为3:2时,聚酰亚胺纤维纸物理性能最佳。     

四元高分子分散剂的合成及其在研磨重质碳酸钙中的应用

以甲基丙烯酸、衣康酸、烯丙基磺酸钠和苯乙烯为单体,通过水溶液自由基共聚合,制备了一种四元高分子分散剂.研究了分散剂用量、相对分子质量及其PH值对不同质量分数的重质碳酸钙粘度、粒径和稳定性的影响.分散剂相对分子质量为10045,PH值为9.0时,对研磨GCC分散效果最好.分散剂适宜高固含量GCC悬浮液的制备.研磨质量分数为70%的GCC,球磨时间为30min,使其粒径为1.9μm,粘度降至201mPa·s,所需分散剂的用量为0.15%,其悬浮液沉降体积百分数(7d后测定)为60.5%.     

废弃羊毛短纤维可降解湿法非织造布的开发

为了回收再利用废弃羊毛,利用湿法非织造工艺对其进行加工。纤维悬浮液的配置是湿法非织造工艺的关键,所以在纤维悬浮液配置单因素实验的基础上,以分散剂CPAM质量分数、表面活性剂CTAB质量分数、悬浮液pH值为因素,悬浮液的分散度为考察指标,设计正交试验,得出悬浮液最优配置工艺,并对优化后制备的湿法非织造材料进行性能测试。结果表明:影响悬浮液分散度的最主要因素是分散剂CPAM质量分数,其次是表面活性剂CTAB质量分数、悬浮液pH值,优化后的工艺为:CPAM质量分数2%,CTAB质量分数2%,悬浮液pH值在3～4之间;性能测试表明产品的基本性能较好,在自然条件下2个月内可完全降解。     

高分散水性碳纤维的制备

本研究以壳聚糖盐酸盐（CHI）和十二烷基磺酸钠（SDS）制备改性剂（CHI&SDS）,采用浸渍法对BHM3碳纤维进行表面改性,以提升BMH3碳纤维在水中的分散能力。系统研究了CHI/SDS质量比、CHI&SDS改性剂质量分数及纤维长度对改性BMH3碳纤维在水中分散性的影响,并通过X射线光电子能谱仪和动态接触角测试仪,对改性BMH3碳纤维化学结构和表面润湿性进行了表征。结果表明,BMH3碳纤维经过质量分数0.15%,CHI/SDS质量比=25∶1的CHI&SDS改性剂改性后,纤维长度5 mm的改性BMH3碳纤维在水中的分散率可达96.2%,相较于未改性碳纤维提升了87.5个百分点。改性BMH3碳纤维表面含氧官能团数量显著提升,水接触角明显降低,这是BMH3碳纤维分散性能改善的原因,也是成功实现高分散水性碳纤维制备的基础。     

碳纤维长度对三层梯度孔碳纸性能的影响研究

为研究不同长度的碳纤维配抄制备的梯度孔碳纸性能,本研究选取3种长度(2、4和8 mm)的碳纤维原料,探讨不同分散剂类型和纤维长度配比对单层碳纸和三层梯度孔碳纸的匀度、电阻率、抗张强度、孔隙率和透气度的影响。结果表明,卡波姆(Carbomer)作为分散剂得到的碳纤维分散效果最佳,分散稳定性指数为4.04。匀度指数在10～13之间的单层碳纸性能较好,其电阻率为90 mΩ·cm,抗张强度为0.250 kN/m,孔隙率为92%,透气度为1 200 L/(m2·s)。与单层碳纸相比,三层梯度孔碳纸的抗张强度(0.410 kN/m)和透气度(1 230 L/(m²·s))有所增加,且碳纤维长度配比对三层梯度孔碳纸的孔隙形貌影响显著;长度4和8 mm的碳纤维配抄制备的三层梯度孔碳纸的性能优于其他2组(2和4 mm配抄及2和8 mm配抄),其电阻率低至19.53 mΩ·cm,孔隙率为92%。     

球磨法制备分散红60微纳米分散液的研究

采用氧化锆珠作为球磨介质,以木质素磺酸钠和萘磺酸钠甲醛缩合物为分散剂,讨论了球磨处理C.I.Disperse Red60染料制备微纳米染料分散液的工艺参数对染料粒径和分散稳定性的影响.结果表明,不同直径氧化锆混合的球磨介质优于单一直径氧化锆,木质素磺酸钠与萘磺酸钠混合分散剂优于单一分散剂.当分散液中染料用量为20%,m(染料)∶m(分散剂)=1∶1,复合分散剂m(木质素磺酸钠CBOS-4)∶m(萘磺酸钠MF)=2∶1,多元醇添加剂用量为10%(对染液总质量),采用m(Φ=2 mm)∶m(Φ=1 mm)∶m(Φ=0.5mm)=17.5∶65∶17.5混合氧化锆球珠作为介质,m(染料)∶m(介质)=1∶20,球磨48 h,得到了稳定的染料分散液,颗粒平均粒径D50为132 nm.     

辣椒制品中罗丹明B的基质固相分散提取条件优化

采用改进的基质固相分散提取技术提取辣椒制品中的罗丹明B,对提取工艺进行优化。选择分散剂种类、分散剂与样品质量比、洗脱剂组成及洗脱剂用量作为研究因素,以提取液中罗丹明B的含量为考察指标,运用L16(45)正交试验优选出了辣椒面中提取罗丹明B的最优工艺条件:分散剂硅胶,分散剂与样品质量比例1∶1;洗脱剂为质量分数80%乙腈水溶液,洗脱剂用量20 mL。辣椒油中提取罗丹明B最优工艺条件是:分散剂中性氧化铝,分散剂与样品质量比例2∶1;洗脱剂为体积分数80%甲醇水溶液,洗脱剂用量20 mL。辣椒酱中提取罗丹明B最优工艺条件是:分散剂中性氧化铝,分散剂与样品质量比例3∶1;洗脱剂为质量分数80%乙腈水溶液,洗脱剂用量5 mL。该提取方法萃取工艺简单,操作时间短,所需有机溶剂种类少,属环境友好型萃取方式。     

液体分散染料的制备及应用

利用实验室自制的聚羧酸盐类分散剂制备液体分散染料,研究了分散剂用量和种类对分散染料粒径的影响。结果表明:分散剂质量分数为15%(对染料质量),染料含固量为10%时,制备的液体分散染料粒径为194.5 nm,多分散指数(PDI)为0.220,离心稳定性为95.7%,放置30 d后平均粒径在250 nm以下。将制备的液体分散染料分散橙30、分散蓝291∶1和分散紫93∶1按照质量比3.7∶1.3∶1.0拼混后染涤纶,可染得颜色均匀的藏青色,且各项色牢度皆优。     

阴离子表面活性剂对超细颜料水性分散体系性能的影响

分别以3种阴离子表面活性剂[亚甲基二萘磺酸钠(NN0)、十二烷基硫酸钠(SDS)、十二烷基苯磺酸钠(DBS)]为分散剂,用M-110EHI 型高压高剪切微流喷射粉碎机制备阴离子型超细有机颜料水性分散体系,研究了粉碎次数对颜料粒径的影响,讨论了不同分散剂对体系中颜料粒径、粘度、稳定性能及对棉织物染色性能的影响.结果表明:使用各种阴离子分散剂、粉碎25次,可使颜料颗粒的粒径达到最小,在相同粉碎次数下,降低颜料粒径效果的次序为NNODBSSDS.各分散剂用量为12.5%(对颜料质量)时,可使颜料粒径最小和体系粘度降到较低值;分散剂NNO本身具有萘环结构,可以和颜料粒子表面形成更为牢固的吸附,其带电荷数也高于其他两种分散剂,对分散体系的稳定作用也更强.相对于常规颜料体系,超细颜料分散体系可将棉织物的颜色染得更深.     

Reliable identification of grapevine rootstock varieties using RAPD PCR on woody samples

Since grapevine ( Vitis spp .) rootstock material is being traded increasingly as disbudded woody material a lack of distinctive morphological features on such material necessitates an alternative and reliable means of identification. Methods described here were developed for rapid and efficient extraction of DNA from woody samples rich in phenolic compounds and polysaccharides, and for subsequent identification of varieties by RAPD PCR. Using these methods, and with the application of only one selected RAPD primer, we were able to differentiate sixteen rootstock varieties, including the seven varieties most commonly used in Germany. Problems commonly encountered with reproducibility of RAPD patterns were avoided by choosing primers with a dinucleotide sequence and a high G/C content that allowed a rather high annealing temperature of 45°C. Methods described here should also be useful for other horticultural crops, especially those with woody tissues rich in phenolic compounds and polysaccharides.     

Chlorohydrins of bisphenol A diglycidyl ether (BADGE) and of bisphenol F diglycidyl ether (BFDGE) in canned foods and ready-to-drink coffees from the Japanese market

BADGE.2HCl and BFDGE.2HCl were determined in 28 samples of ready-to-drink canned coffee and 18 samples of canned vegetables (10 corn, 5 tomatoes and 3 others), all from the Japanese market. HPLC was used as the principal analytical method and GCMS for confirmation of relevant LC fractions. BADGE.2HCl was found to be present in one canned coffee and five samples of corn, BFDGE.2HCl in four samples of canned tomatoes and in one canned corn. No sample was found which exceeded the 1mg/kg limit of the EU for the BADGE chlorohydrins. However the highest concentration was found for the sum of BFDGE.2HCl and BFDGE.HCl.H₂O at a level of 1.5mg/kg. A Beilstein test confirmed that all cans containing foods contaminated with BADGE.2HCl or BFDGE.2HCl had at lest one part coated with a PVC organosol.     

European priorities for research to support legislation in the area of food contact materials and articles

A strong science base is required to underpin the planning and decision-making process involved in determining future European community legislation on materials and articles in contact with food. Significant progress has been made in the past 5 years in European funded work in this area, with many developments contributing to a much better understanding of the migration process, and better and simpler approaches to food control. In this paper this progress is reviewed against previously identified work-areas (identified in 1994) and conclusions are reached about future requirements for R&D to support legislation on food contact materials and articles over the next 5 or so years.     

Aroma characterization of various apricot varieties using headspace–solid phase microextraction combined with gas chromatography–mass spectrometry and gas chromatography–olfactometry

The characterization of the aromatic profile of several apricot cultivars with molecular tracers in order to obtain objective data concerning the aromatic quality of this fruit was undertaken using headspace–solid phase microextraction (HS–SPME). Six apricot cultivars were selected according to their organoleptic characteristics: Iranien, Orangered, Goldrich, Hargrand, Rouge du Roussillon and A4025. The aromatic intensity of these varieties measured by HS–SPME–Olfactometry were defined and classified according to the presence and the intensity of grassy, fruity and apricot like notes. In the six varieties, 23 common volatile compounds were identified by HS–SPME–GC–MS. Finally, 10 compounds, ethyl acetate, hexyl acetate, limonene, β-cyclocitral, γ-decalactone, 6-methyl-5-hepten-2-one, linalool, β-ionone, menthone and (E)-hexen-2-al were recognized by HS–SPME–GC–O as responsible of the aromatic notes involved in apricot aroma and considered as molecular tracers of apricot aromatic quality which could be utilized to discriminate apricot varieties.     

Tests of potential functional barriers for laminated multilayer food packages. Part I: Low molecular weight permeants

The advent of the functional barrier concept in food packaging has brought with it a requirement for fast tests of permeation through potential barrier materials. In such tests it would be convenient for both foodstuffs and materials below the functional barrier (sub-barrier materials) to be represented by standard simulants. By means of inverse gas chromatography, liquid paraffin spiked with appropriate permeants was considered as a potential simulant of sub-barrier materials based on polypropylene (PP) or similar polyolefins. Experiments were performed to characterize the kinetics of the permeation of low molecular weight model permeants (octene, toluene and isopropanol) from liquid paraffin, through a surrogate potential functional barrier (25 μm-thick oriented PP) into the food simulants olive oil and 3% (w/v) acetic acid. These permeation results were interpreted in terms of three permeation kinetic models regarding the solubility of a particular model permeant in the post-barrier medium (i.e. the food simulant). The results obtained justify the development and evaluation of liquid sub-barrier simulants that would allow flexible yet rigorous testing of new laminated multilayer packaging materials.     

Textural Properties of Cold-set Gels Induced from Heat-denatured Whey Protein Isolates

A 9% whey protein (WP) isolate solution at pH 7.0 was heat-denatured at 80°C for 30 min. Size-exclusion HPLC showed that native WP formed soluble aggregates after heat-treatment. Additions of CaCl2 (10–40 mM), NaCl (50–400 mM) or glucono-delta-lactone (GDL, 0.4–2.0%, w/v) or hydrolysis by a protease from Bacillus licheniformis caused gelation of the denatured solution at 45°C. Textural parameters, hardness, adhesiveness, and cohesiveness of the gels so formed changed markedly with concentration of added salts or pH by added GDL. Maximum gel hardness occurred at 200 mM NaCl or pH 4.7. Increasing CaCl2 concentration continuously increased gel hardness. Generally, GDL-induced gels were harder than salt-induced gels, and much harder than the protease-induced gel.     

Influence des ions sur le pouvoir hydratant de l'ure e: e tude sur peau de porc ex vivo

This study deals with the influence of ions (NaCl and MgSO4) in a W/O emulsion containing 10% urea. Moisturization kinetics are assessed by corneometry on pig skin ex vivo. The formula's influence on urea penetration is measured by infrared spectrometry with an ATR device and the stripping method. Corneometry and spectroscopy were chosen to record simultaneously the hydratation levels and urea localization into superficial cell layers. Urea crystallization after evaporation of emulsions and aqueous solutions is described. Results show that urea does not hydrate nor penetrate when applied to the skin through an aqueous gel. In a W/O emulsion, sodium chloride increases the ability of urea to moisturize without improving penetration. In vitro urea crystallization is disturbed by sodium chloride or magnesium sulphate for solutions and emulsions. This stabilization by ions is correlated with good moisturization values. The stabilization of urea in the solute state provided by ions increases its water epidermal binding capacity without enhancing penetration.     

Occurrence of bisphenol-F-diglycidyl ether (BFDGE) in fish canned in oil

The levels of bisphenol-F-diglycidyl ether (BFDGE) were quantified as part of a European survey on the migration of residues of epoxy resins into oil from canned fish. The contents of BFDGE in cans, lids and fish collected from all 15 Member States of the European Union and Switzerland were analysed in 382 samples. Cans and lids were separately extracted with acetonitrile. The extraction from fish was carried out with hexane followed by re-extraction with acetonitrile. The analysis was performed by reverse phase HPL C with fluorescence detection. BFDGE could be detected in 12% of the fish, 24% of the cans and 18% of the lids. Only 3% of the fish contained BFDGE in concentrations considerably above 1mg/kg. In addition to the presented data, a comparison was made with the levels of BADGE (bisphenol-A-diglycidyl ether)analysed in the same products in the context of a previous study.     

Analysis on Economic Indicators from 62 Enterprises in Printing Machinery Industry in Q1 2014

Operation of printing machine industry was still unsatisfactory in the first quarter of 2014.Analysis on operation of printing machine industry.a.Market demand was not strong;sales of product undulated and declined.According to the statistics,the total industrial output value fell by 19.28% in the first quarter of 2014 than the average quarter value in 2013; industrial added value decreased by 4.16%; sales revenue dropped by 22.83%. h. Business operation of enterprises was in poor condition. c. R＆D of new products is an important transformation guarantee for enterprises. d. To take self explore new ways upgrading advantages,and explore new ways.