造纸法烟草基片外加植物纤维的优化

选取不同制浆方式的浆种和不同种类的植物纤维进行实验,考察其对造纸法烟草基片物理性能的影响,选取效果较好的外加纤维进行复配,确定外加纤维种类并对其添加量进行优化。实验结果发现:采用木素含量低的阔叶木漂白硫酸盐浆、针叶木漂白硫酸盐浆、#1木浆、#2木浆、漂白龙须草浆对改善烟草基片的物理性能和降低烟草薄片的有害物质比较有效;实验最终确定添加20%漂白硫酸盐木浆(针叶木漂白硫酸盐浆∶阔叶木漂白硫酸盐浆=1∶1),在改善烟草基片物理性能的同时显著降低了烟草薄片中的有害物质。     

细小纤维对造纸法烟草薄片基片物理性能的影响

利用漂白硫酸盐针叶木浆制备不同长度的细小纤维,考察其对烟草薄片基片物理性能(抗张强度、松厚度、柔软性能、粗糙度和透气度)和浆料滤水性能的影响,并对细小纤维用量进行优化.实验结果表明,随着细小纤维平均长度的降低,基片的抗张强度提高,与此同时松厚度和柔软性能受到影响,浆料的滤水性能下降;木浆纤维用量15％、添加平均长度0.622mm的细小纤维可较好地改善基片的各项物理性能,其中细小纤维合适的用量为1.5％;与传统工艺(木浆纤维用量20％)相比,木浆纤维用量降低了25％左右,减少了卷烟木质杂气的产生量.     

纳米纤维素作为桉木浆造纸助剂的研究

比较了加入纳米纤维素（NFC）的漂白桉木浆与抄造书写印刷纸和胶版印刷纸的传统漂白桉木浆的物理性能。为此,制备了3种浆料：打浆浆料、加入NFC的未打浆浆料、轻度打浆且加入NFC的浆料。结果表明,加入NFC的未打浆浆料的物理性能与抄造书写印刷纸浆料的物理性能基本相同;预先轻度打浆而后加入NFC的浆料的性能最好。这一结果显示,加入NFC可以降低打浆强度而不会降低浆料的强度性能。     

纳米微纤化纤维素在口罩用过滤材料中的应用研究

本研究采用纳米微纤化纤维素(NFC)和不同纤度的聚对苯二甲酸乙二醇酯(PET)纤维,通过湿法造纸技术,制备出口罩用NFC过滤材料,并探究了NFC含量、PET纤维纤度及过滤材料定量对过滤材料性能的影响。结果表明,NFC含量是影响过滤材料性能的主要因素,当NFC含量超过13.5 g/m~2时,过滤材料对PM2.5的过滤效率可以达到95%以上。由于过滤材料定量和PET纤维纤度会影响过滤材料的疏松性,进而影响过滤性能和透气性,需要调整过滤材料定量和PET纤维的纤度搭配,以实现过滤效率和透气的平衡。最优的过滤材料配方为:30%NFC,50%0.1 dtexPET纤维,5%0.7 dtexPET纤维,5%1.5 dtexPET纤维,10%双组分PET纤维,过滤材料定量45 g/m~2,由此制备得到的NFC防护口罩,过滤效率达到国家标准GB/T 32610—2016中I级(99%)的要求,防护效果达到A级。     

纳米纤维素与木浆混抄制备锂离子电池隔膜的性能研究

以纳米纤维素和针叶木浆为原料,通过湿法造纸工艺,可以获得性能优异的纳米纤维素（NFC）隔膜。研究表明,与国产聚丙烯(PP)隔膜和美国Celgard 2400 PP隔膜相比,NFC隔膜具有较高的孔隙率、良好的润湿性、较高的吸液率,此外,NFC隔膜有很好的热稳定性,在200℃加热1 h后几乎没有收缩。     

辛烯基琥珀酸纳米纤维素纤维酯的制备及性质研究

本文以蒸汽闪爆(high density steam flash-explosion,HDSF)预处理技术对秸秆进行处理,并结合酶解和高压均质处理制得纳米纤维素纤维(Nanofibrilled cellulose,NFC)。研究NFC与辛烯基琥珀酸酐(Octenyl Succinic Anhydride,OSA)的酯化反应条件,并探讨合成的辛烯基琥珀酸纳米纤维素纤维酯(OSA-NFC)在强力吸附油脂膳食纤维方面的应用。结果表明在OSA-NFC的取代度小于0.02的前提下,酯化改性的最佳反应条件为:反应时间4 h,温度40℃,p H8.5,OSA为NFC干重的3%,NFC含量3%,反应效率可以达到95%以上。且OSA酯化改性后,NFC的持油力可以达到5.56~9.33 g/g,具有作为可强力吸附油脂的膳食纤维应用的潜力。     

纳米纤维素增强芳纶云母纸性能的研究

为了改善芳纶云母纸成纸性能,研究了添加纳米纤维素(NFC)对芳纶云母纸性能的影响;同时采用单因素控制法确定NFC用量和超声波处理NFC对芳纶云母纸性能的影响,得到优化的工艺条件;并探究NFC增强芳纶云母纸的机理。结果表明,NFC添加量为10%(NFC∶芳纶∶云母=1∶2∶7)时,相比空白样,纸张抗张强度增加了447.6%,介电强度增加了6.3%;超声波处理NFC的最佳条件为:超声波功率1000 W,处理时间15 min,NFC初始浓度1.5%;相对于未经超声波处理的NFC,超声波处理NFC的NFC-芳纶云母纸的抗张强度增加了197.2%,介电强度增加了26.9%。NFC的加入填充了芳纶云母纸表面及内部的空隙,又在一定程度上减少了芳纶纤维的用量。     

利用细小纤维降低造纸法 烟草薄片木浆纤维添加量

实验利用针叶木漂白硫酸盐浆制备细小纤维,将其作为生产烟草薄片的增强剂,考察对烟草薄片物理性能(抗张强度、松厚度、柔软性能)和浆料滤水性能的影响,通过实验优化出合适的细小纤维添加量。实验结果表明:随着细小纤维添加量的增加,烟草薄片的抗张强度明显提高,与此同时松厚度和柔软性受到影响,烟草浆料的滤水性能也随之下降。在木浆添加量12%,细小纤维(平均长度0.450 mm)添加量1%的条件下抄造的烟草薄片各项物理性能较好,与工厂现有工艺相比,在抗张强度略微降低的情况下,松厚度提高了3.4%,柔软性提高了39.3%,得到了较大改善;同时木浆用量减少了35%,有效地降低了木质气的产生。     

改善造纸法烟草基片松厚度的研究

研究了造纸法烟草基片生产过程中,烟梗浆与烟末浆比例、木浆和沉淀碳酸钙(PCC)用量对烟草基片松厚度和抗张强度的影响。结果表明,适宜的木浆添加比例约为20%;增加烟草浆中烟末浆的比例对基片的松厚度有利,但是对烟草基片的强度性能具有负面影响,烟草浆中适宜的烟末浆比例约为50%。     

均质法和超声法制备NFC及其纳米纸性能研究

以漂白硫酸盐桉木浆纤维为原料,进行TEMPO氧化预处理,再采用均质法和超声法及二者结合法分别制备出纳米纤丝纤维素(Nanofibrillated Cellulose,NFC),再经溶液浇铸法制备纳米纸。重点探讨了不同制备方法对NFC特性及其纳米纸性能的影响。结果表明,不同能耗下,超声2 h、4 h比均质2次、5次制备的NFC的透明性更好,长径比更大,直径更小,最小宽度可达19 nm。工艺能耗低于20 k Wh时,与均质处理相比,超声处理强度(能耗)的增加更有利于纳米纸拉伸强度和透湿率的提高,同时超声2 h、4 h比均质2次、5次制备的NFC纳米纸的光学性能更好,其中超声4h制备的NFC得到的纳米纸拉伸强度与透光率最高,分别为155.8 MPa、89.45%,优于一般的聚合物薄膜,有望应用于柔性显示电子器件的基材。     

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.     

The Ministry of Environmental Protection Issued "Feasible Technology Guidelines for Pollution Prevention and Control in Wood Pulping Process of the Paper Industry (Trial)" and Two Other Guiding Technical Documents

On December 27t＂, 2013, the Ministry of Environmenta Protection announced that, in order to implement ＂The Environmental Protection Law of the People＇ s Republic of China＂, improve the working system in environmenta protection technologies, and promote technologica advancement in pollution prevention, the Ministry of Environmental Protection sponsored the formulation of three guiding technical documents including ＂Feasible Technology Guidelines for Pollution Prevention and Contro n Wood Pulping Process of the Paper Industry （Trial）＂     

1~(st) Intelli-Tissue~ EcoEc Tissue Machine Supplied by PMP Group Successfully Put into Operation in China

正On April 29th,2014,Intelli-Tissue EcoEc tissue machine supplied by PMP Group successfully put into operation at Hebei Xuesong Paper Co.,Ltd.,this is the first such kind of paper machine of PMP Group in China.