松香酯的合成与应用研究

本文采用实验室自制的松香十八醇酯对文化用纸进行了中性施胶实验.结果表明,这种施胶剂适于在中性条件下施胶,其最佳施胶pH值为7.0.可以采用少量的矾土与阳离子淀粉及APAM组合成复合型助留剂.对漂白亚硫酸氢镁法苇浆和漂白硫酸盐木浆的混合浆料进行施胶,随着苇浆配比的增加,施胶效果改善.在苇浆:木浆=8:2,pH值为7.0时,复合助留剂的适宜配比为:矾土1%(对浆,下同),阳离子淀粉1%、APAM 0.04%,此时手抄片的施胶度可以达到100s以上.     

聚合氯化铝在中性施胶中的应用

在中性条件下，利用松香胶对漂白麦草浆进行施胶，研究聚合氯化铝(PAC)作为施胶沉淀剂的施胶效果，通过考察阴离子分散松香胶、PAC、阳离子淀粉、阳离子聚丙烯酰胺等对施胶效果的影响，得出最佳的工艺条件：阴离子分散松香胶用量1％，PAC用量4％，CPAM用量0．03％，填料15％，在pH值7．0时的施胶度为1．00mm．     

口杯原纸分散松香胶内部施胶研究

从施胶顺序、pH值、松香胶用量、硫酸铝用量、干燥温度等几方面分别探讨了阳离子分散松香胶和阴离子分散松香胶对口杯原纸的内部施胶工艺条件。结果表明,阳离子分散松香胶施胶的最佳条件为:逆向施胶,pH值5.0~5.5,松香胶用量2.5%,硫酸铝用量4%,干燥温度90℃;阴离子分散松香胶施胶的最佳条件为:逆向施胶,pH值4.5~5.0,松香胶用量3%,硫酸铝用量6%,干燥温度90℃。     

阳离子松香/AKD中性施胶剂的制备及应用

以N甲-基吡咯烷酮（NMP）为助溶剂,丙烯酰胺（AM）、甲基丙烯酰氧乙基三甲基氯化铵（DMC）、丙烯酸十八酯（ODA）、苯乙烯（St）为单体,通过无皂乳液共聚反应合成了阳离子高分子乳化剂,并制备了阳离子松香/AKD乳液。研究了高分子乳化剂合成中AM、DMC用量对乳液稳定性的影响,乳液中松香、AKD、高分子乳化剂质量比对乳液稳定性及施胶性能的影响,以及纸浆pH值、乳液用量对施胶效果的影响。结果表明：AM用量为35%,DMC用量为15%,松香、AKD和高分子乳化剂的质量比为11∶4∶3时乳液稳定性较好。适宜的施胶条件为：采用逆向施胶工艺,松香、AKD和高分子乳化剂的质量比为11∶4∶3,纸浆pH值为6,乳液用量为1%。     

阳离子松香中性施胶剂的应用

以十二叔胺、环氧氯丙烷、松香为原料合成了阳离子改性松香乳化剂乳化松香,并制备出一种阳离子松香中性施胶剂,探讨了其对纸张施胶的影响因素;实验结果表明,该阳离子松香中性施胶剂施胶效率高,在中性条件下具有良好的施胶效果。     

阳离子松香基聚氨酯型施胶剂的合成及应用

本文主要利用松香和TDI合成聚氨酯预聚体,利用甲基二乙醇胺扩链,最后用亚硫酸氢钠作封闭剂,最后乳化得到阳离子松香型聚氨酯。同时,将此种施胶剂应用于造纸湿部中,研究了扩链剂用量,pH及APAM用量对聚氨酯施胶性能的影响。实验表明,此种施胶剂在中碱性环境中施胶效果较好。     

媒介物质对松香施胶性能影响的初步探讨

利用实验室自制的阳离子分散松香胶,与碳酸锆铵一起对纸张进行浸渍施胶,利用碳酸锆铵与松香羧基之间的反应,研究碳酸锆铵对阳离子分散松香胶的施胶促进作用。并将碳酸锆铵与硫酸铝一起使用,研究这两者在松香施胶中的相互作用及对松香施胶的影响。其中包括阳离子分散松香胶、硫酸铝、碳酸锆铵加入量、加入比例和施胶pH值对松香施胶性能的影响。结果表明,当阳离子分散松香胶用量与碳酸锆铵用量比为4：1时,可以获得较满意的施胶效果;当硫酸铝与碳酸锆铵共同用于松香施胶时,施胶度随碳酸锆铵用量的增加而降低。     

阳离子改性松香胶对二次纤维的施胶作用

本文对一种阳离子改性松香胶在二次纤维中的应用进行了详细的论述,特别是对在不同的阳离子改性松香胶用量、硫酸铝用量、浆料pH值条件下的施胶效果进行了论述.     

阳离子无皂松香/石蜡乳液的制备及其施胶性能

通过无皂乳液聚合法制得阳离子聚丙烯酸酯高分子乳化剂,并以此制备系列阳离子无皂松香/石蜡乳液。研究了高分子乳化剂制备的主要影响因素,并通过与传统的阳离子松香乳液的对比应用实验,分析了阳离子无皂松香/石蜡乳液与传统阳离子松香乳液的差别。结果表明,当w(丙烯酰胺)=25%,w(甲基丙烯酰氧乙基三甲基氯化铵)=20%,w(聚丙烯酸酯乳化剂)=15%时,乳液趋于稳定,并具有良好的施胶和增强效果;与传统的阳离子松香乳液相比,阳离子无皂松香/石蜡乳液在较高pH值下仍具有较好的施胶效果,且在相同用量下,阳离子无皂松香/石蜡乳液具有更好的施胶效果。     

阳离子松香中性施胶剂的制备及应用研究

采用自制的阳离子乳化剂乳化松香和改性松香制备了一种阳离子松香中性施胶剂，介绍了该施胶剂的制备技术、应用特性，并对纸张施胶度的影响因素进行了探讨。实验结果表明，阳离子松香中性施胶剂质量稳定、施胶效率高、可用于中性条件下施胶，在pH值6．0-8．0的范围内能获得满意的施胶效果。     

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.     

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.     

Contribution of European research to risk analysis

The European Commission's, Quality of Life Research Programme, Key Action 1—Health, Food & Nutrition is mission-oriented and aims, amongst other things, at providing a healthy, safe and high-quality food supply leading to reinforced consumer confidence in the safety of European food. Its objectives also include the enhancing of the competitiveness of the European food supply. Key Action 1 is currently supporting a number of different types of European collaborative projects in the area of risk analysis. The objectives of these projects range from the development and validation of prevention strategies including the reduction of consumers risks; development and validation of new modelling approaches; harmonization of risk assessment principles, methodologies, and terminology; standardization of methods and systems used for the safety evaluation of transgenic food; providing of tools for the evaluation of human viral contamination of shellfish and quality control; new methodologies for assessing the potential of unintended effects of genetically modified (genetically modified) foods; development of a risk assessment model for Cryptosporidium parvum related to the food and water industries; to the development of a communication platform for genetically modified organism, producers, retailers, regulatory authorities and consumer groups to improve safety assessment procedures, risk management strategies and risk communication; development and validation of new methods for safety testing of transgenic food; evaluation of the safety and efficacy of iron supplementation in pregnant women; evaluation of the potential cancer-preventing activity of pro- and pre-biotic ('synbiotic') combinations in human volunteers. An overview of these projects is presented here.     

低温带皮菜籽粕微粉的不同粒级部分的功能特性

为研究低温带皮菜籽粕微粉的不同粒级部分的功能特性,以经低温脱脂的带皮菜籽粕为原料,经微粉碎后筛分成212~425μm、150~212μm和106~150μm的3个不同粒级的微粉样品,检测这些样品的吸水性、吸油性、乳化性和乳化稳定性、蛋白质体外消化率。结果表明:1 3个不同粒级的微粉样品之间的粗纤维含量存在显著差异,表明三者的结构组成成分有一定差异。23个微粉样品的乳化活性和乳化稳定性随粒度级别的减小而显著增加(P0.01)。33个微粉样品的蛋白质体外消化率随粒度级别的减小而显著增加(P0.01)。4不同粒级带皮菜籽粕微粉样品的吸水性与吸油性受其结构组成物质不同和粒度的双重影响,与粒度的相关性不明显。     

Microbiology of food taints

Fresh and processed foods are often spoilt by the presence of undesirable flavours and odours caused by microbial action. The aim of this paper is to review the current knowledge of microbiologically induced taints that occur in a wide range of foodstuffs, including meats, poultry, fish, crustaceans, milk, dairy products, fruits, vegetables, cereals and cereal products. Examples have been chosen where the compounds responsible for the taint have been identified and sufficient data obtained to demonstrate the involvement of microorganisms. However, in some cases the full identity of the causative organism may not have been elucidated. The types of microorganisms covered by this review include bacteria, fungi, yeasts, actinomycetes and cyanobacteria. Although cyanobacteria do not in general infect foods, their presence in aqueous systems and water supplies can lead to off-flavours in aquatic organisms and processed foodstuffs. Several examples of each of these processes are discussed. Wherever possible, the likely biosynthetic pathway used by the microorganism to produce the offending compound in a foodstuff is indicated.     

Analysis for organic residues from aids to polymerization used to make plastics intended for food contact

Polymers intended for food contact use have been analysed for organic residues which could be attributed to a range of substances employed as polymerization aids (e.g. initiators and catalysts). A wide range of polymers was extracted with solvents and the extracts analysed by gas chromatography-mass spectrometry (GC-MS). The overwhelming majority of substances identified were not derived from aids to polymerization but were oligomers, additives and adventitious contaminants. However, a small number of substances were identified as initiator residues. These included tetramethylsuccinonitrile (TMSN) which was observed in two polymers and it derived from recombination of two azobisisobutyronitrile (AIBN) initiator radicals. Methyl benzoate, benzoic acid, biphenyl and phenyl benzoate were detected in one poly(methyl methacrylate) sample and in two polyvinylchlorides and they are thought to be derived from benzoyl peroxide initiator. TMSN was subsequently targeted for analysis of poly-(methyl methacrylate) plastics using proton nuclear magnetic resonance spectrometry (¹     

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

Experiments were performed to characterize the kinetics of the permeation of different medium molecular weight model permeants: bisphenol A, warfarin and anthracene, from liquid paraffin, through a surrogate potential functional barrier (25 microns-thick orientated polypropylene--OPP) into the food simulants olive oil and 3% (w/v) acetic acid. The characterization of permeation kinetics generally observed the permeation models previously reported to explain the experimental permeation results obtained for a low molecular weight group of model permeants. In general, the model permeants exhibited behaviour consistent with their relative molecular weights with respect to (a) the time taken to attain steady-state permeation into the food simulant in which they were more soluble, (b) their subsequent steady-state permeation rates, and (c) their partition between liquid paraffin and the OPP membrane.     

The development of reference materials for paralytic shellfish poisoning toxins in lyophilized mussel. I: Interlaboratory studies of methods of analysis

This paper describes the first part of a project undertaken to develop mussel reference materials for Paralytic Shellfish Poisoning (PSP) toxins. Two interlaboratory studies were undertaken to investigate the performance of the analytical methodology for several PSP toxins, in particular saxitoxin (STX) and decarbamoyl-saxitoxin (dc-STX) in lyophilized mussels, and to set criteria for the acceptance of results to be applied during the second part of the project: the certification exercise. In the first study, 18 laboratories were asked to measure STX and dc-STX in rehydrated lyophilized mussel material and to identify as many other PSP toxins as possible with a method of their choice. In the second interlaboratory study, 15 laboratories were additionally asked to determine quantitatively STX and dc-STX in rehydrated lyophilized mussel and in a saxitoxin-enriched mussel material. The first study revealed that three out of four postcolumn derivatization methods and one pre-column derivatization method sufficed in principle to determine STX and dc-STX. Most participants (13 of 18) obtained acceptable calibration curves and recoveries. Saxitoxin was hardly detected in the rehydrated lyophilized mussels and results obtained for dc-STX yielded a CV of 58% at a mass fraction of 1.86 mg/kg. Most participants (14 out of 18) identified gonyautoxin-5 (GTX-5) in a hydrolysed extract provided. The first study led to provisional criteria for linearity, recovery and separation. The second study revealed that 6 out of 15 laboratories were able to meet these criteria. Results obtained for dc-STX yielded a CV of 19% at a mass fraction of 3.49mg/kg. Results obtained for STX in the saxitoxin-enriched material yielded a CV of 19% at a mass fraction of 0.34mg/kg. Saxitoxin could not be detected in the PSP-positive material. Hydrolysis was useful to confirm the identity of GTX5 and provided indicative information about C1 and C2 toxins in the PSP-positive material. The methods used in the second interlaboratory study showed sufficiently consistent analysis results to undertake a certification exercise to assign certified values for STX and dc-STX in lyophilized mussel.     

Focus on China's Paper Industry

In the English section of this issue, 〈China Paper Newsletters〉 will introduce ＂National Development and Reform Commission Issued Announcement for Selection of Major Preliminary Research Projects for the ＇13th Five-Year Plan＇＂, ＂2013 Annual Report of China＇s Paper Industry＂, and news of projects and other policies.     

Listen to downstream & search for innovation

正Nowadays,textile enterprises are all taking efforts in transformation and upgrading,like improving producing capacity and optimizing production structure to face market downturn.It claimed a higher request to the standard of textile equipments.In the upcoming of ITMA ASIA+CITME 2014exhibition,this magazine have interviewed several branch associations and a series of relative enterprises,to summarize industrial developing status