果糖基碳微球的制备及其吸附性能研究

以果糖为碳前驱体、聚环氧乙烷-聚环氧丙烷-聚环氧乙烷三嵌段共聚物（Pluronic P123）为模板剂,采用软模板水热碳化法制备果糖碳微球。利用扫描电子显微镜（SEM）、透射电子显微镜（TEM）对其形貌进行表征,探究果糖碳微球最佳制备条件,并对其吸附亚甲基蓝的性能及影响因素进行了研究。结果表明,水热碳化时间为6 h时,果糖碳微球尺寸分布均匀,表面光滑。在最佳吸附条件下,果糖碳微球对亚甲基蓝的吸附量可达91.43 mg/g,经5次吸附循环后其吸附量仍为初始吸附量的76.9%,具有良好的循环使用性能;其吸附过程符合准二级吸附动力学,Langmuir等温吸附模型对其吸附过程的拟合更准确,表明亚甲基蓝以单分子层方式吸附于果糖碳微球表面,亚甲基蓝各分子间无相互作用。     

木质素基多孔纳米碳纤维在超级电容器电极材料中的应用

以乙酸木质素、聚氧化乙烯、乙酰丙酮铁和聚乙烯吡咯烷酮为原料,通过静电纺丝以及随后的碳化过程制备得到木质素基多孔纳米碳纤维,将其用作超级电容器电极材料。多孔碳电极在0.5A/g的电流密度下的比电容值为67.05F/g,比未添加开孔剂的木质素基碳纤维电极提高了88%。多孔碳电极还具有良好的循环性能,在0.5A/g的电流密度下循环1000次后的保留电容为初始的92%。此外,木质素基多孔纳米碳纤维由于开孔效果比表面积增加,微孔和介孔的增加促进了电解液离子的转移和吸附,增强了材料的电化学性能。制备的木质素基多孔纳米碳纤维表现出来的性能使它们具有作为能源存储的可能性。     

用于超级电容器的木质纤维素基碳材料的制备及其性能研究

本研究以KOH为活化剂,采用先预碳化再活化和先活化再碳化的2种不同工艺处理方法,制备了不同结构的木质纤维素基碳材料。前一种方法合成的多孔碳材料缺陷丰富、比表面积高达1737 m²/g。受益于其特殊的构效关系,该多孔碳材料作为超级电容器的电极表现出了优异的电化学性能,在0.5 A/g的电流密度下,其比容量达到194 F/g。     

碳基复合纳米纤维的制备与表征及其电容性

以DMF为溶剂,利用静电纺丝法制备了PAN/Co(OAc)2/CNTs复合纳米纤维,并通过高温碳化及活化的方法得到多孔碳基复合纳米纤维。利用扫描电子显微镜(SEM)、X射线衍射仪（XRD）、ASAP 2020及Solartron 1470分别研究了纤维的表面形貌、碳基复合纳米纤维的物相、比表面积和材料的电化学性能。研究结果表明：多孔碳材料为C/Co/CNTs复合纳米纤维;前驱体复合纳米纤维表面较为光滑,高温处理处部分纤维出现断裂;碳基复合纳米纤维的比表面积和孔体积分别为771m2/g和0.347cm3/g;在电流密度为1.0A/g时复合纳米纤维的比容量可达210F/g,电流为0.5mA时能量密度为3.1Wh/Kg,电流为5 mA时功率密度为2337W/Kg     

棉纤维制得的碳微球结构及吸附性能研究

探讨棉纤维制得碳微球的制备工艺、结构特点和吸附性能。采用水热碳化法,以棉纤维为原料制备碳微球,对碳化温度做了系列研究,并测试了所制得碳微球的形貌、红外光谱、X射线衍射图、粒径分布和吸附性能。结果表明:当催化剂浓度一定、碳化温度为150℃时,纤维开始碳化,并随着温度的升高,碳化程度逐渐增强,在210℃时即得到较为良好的碳化状态,结晶区大部分被破坏,生成丰富的官能团,平均颗粒直径在530.6nm左右,其吸附量达到了145.420mg/g。认为废旧棉织物制备出的碳微球具有较好的吸附性能。     

酸掺杂聚苯胺电极材料的制备及其电化学性能研究

本研究以苯胺为单体,过硫酸铵为氧化剂,植酸为掺杂酸,与木质素磺酸盐进行化学聚合,通过原位化学氧化法合成了电子传导能力良好和电容性能优异的木质素磺酸盐/聚苯胺（LS/PANI）电极材料,采用场发射扫描电子显微镜（FESEM）、傅里叶变换红外光谱仪（FT-IR）和比表面积及孔径分析仪（BET）对LS/PANI电极材料进行分析表征;运用循环伏安、充放电、电化学阻抗等测试LS/PANI电极材料电化学性能。结果表明,LS/PANI电极材料具有良好的电容性能和较好的循环稳定性;在充放电0.5 A/g的电流密度下比电容可以达到509.3 F/g,在充放电电流密度为10 A/g时,循环5 000次后仍能保留63.23%的电容。     

废旧粘胶织物水热碳化制备碳微球的研究

研究废弃再生纤维素织物的回收利用途径。以废弃粘胶织物为原料,通过水热碳化法对粘胶纤维进行水热处理制备碳微球,考察了水热合成的温度、停留时间对水热碳化过程的影响。测试了所制备碳微球的微观形貌、红外光谱、X射线衍射图谱、热重及能谱。结果表明:当反应温度为260℃、停留时间为8 h时获得最佳碳微球形貌;粘胶纤维水热碳化起始温度为180℃;粘胶纤维制备的碳微球为无定形结构,石墨化程度较低;随着停留时间的延长,碳微球粒径越来越大;随着反应温度的提高,碳产物的含碳量及热稳定性提高。认为:粘胶纤维水热碳微球表面含有羧基、羰基和羟基等丰富的官能团,具有优良的亲水性和表面活性。     

基于桉木预水解液的多形态碳微球的制备研究

以桉木溶解浆生产过程中的副产物预水解液为原料,采用水热碳化工艺对预水解液进行处理,以制备碳微球。探讨了水热碳化过程中聚（4-苯乙烯磺酸-马来酸共聚物）钠盐（PSSMA）用量对碳微球形貌及得率的影响,并探究了不同结构碳微球的成形机理。结果表明,预水解液是制备碳微球的理想碳源,PSSMA可通过在碳微球表面提供静电斥力以调控碳微球形貌,使碳微球由交联的球簇结构转变为单分散微球结构和微球超结构。随着PSSMA用量增加和碳化时间的延长,碳微球及其超结构的粒径均呈先下降再趋于平缓的趋势;但PSSMA对碳微球得率的影响较小。     

木质素及其衍生碳在电化学储能材料中的应用

木质素作为存有量巨大的可再生天然碳基有机聚合物，具有特殊的天然纤维结构及丰富的官能团等特性。将不同的木质素进行热处理碳化及激活后，可转变为高附加值的碳材料，如多孔碳、碳纳米纤维、活性碳等。本文从木质素复合材料及木质素衍生碳两个方面进行了介绍，对造纸工业副产品木质素在电化学储能材料中的最新应用研究进行了综述。结合目前双碳背景，木质素及其衍生碳的研究对造纸行业副产品的综合利用具有极大的意义，为造纸工业的清洁化生产提供了新的思路。     

熔盐水合物处理对生物质基多孔碳材料电化学性能的影响

本研究以速生杨木边材木片为原料进行自水解预处理,将无机熔盐水合物和自水解预处理后的杨木片（APW）加入盐酸溶液中浸渍,经冷冻干燥、碳化、酸洗、水洗及干燥后得到木质生物质基多孔碳材料。探究了APW的不同无机熔盐水合物活化处理对多孔碳材料物理结构性能的影响,测试了将其作为超级电容器电极材料的电化学性能。结果表明,在盐酸溶液中,无机熔盐水合物ZnCl₂和 ZnCO₃活化处理均有利于提高木质生物质基多孔碳材料的电化学性能,且前者比后者的作用效果更强,ZnCl₂活化处理制备的木质生物质基多孔碳材料无序结构更多;当用作超级电容器中的电极材料时,活化剂总质量一定,以ZnCl₂和ZnCO₃组合制备的多孔碳材料的电化学性能更具有优势,在0.2 A/g电流密度下,所制备的电极材料质量比容量可达到143.20 F/g;在2.0 A/g电流密度下,其循环5000次的电容保持率为99.90%;另外,在10 mV/s的扫描速率下,其循环伏安曲线保持了良好闭合的近似矩形形状。     

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