CMC/木质纤维复合纸的制备及性能

以羧甲基纤维素(CMC)和桉木浆为原料,将桉木浆抄造成纸张后浸渍CMC溶液制备CMC/木质纤维复合纸。探讨了CMC的浸渍量对复合纸的光学性能(透光率和雾度)、力学性能(拉伸强度和耐折度)的影响规律。结果表明:当CMC的浸渍量为65%时,CMC/木质纤维复合纸具有优异的光学性能和力学性能,其透光率为91%,雾度为82%,拉伸强度达142 MPa,耐折次数为1516次。     

木质纤维聚合度对高透光率纤维素薄膜力学性能的影响

以氢氧化钠-亚硫酸盐-蒽醌-甲醇（ASAM）法制备的高聚合度针叶木浆为原料,通过调控漂白时间和漂白剂用量制得形态相近、聚合度不同的4种木质纤维;随后,通过浸渍法将羧甲基纤维素钠（CMC）与上述纤维抄造的原纸复合,制得高透光率木质纤维/CMC纤维素薄膜（以下简称薄膜）,并研究纤维聚合度对薄膜力学性能的影响。结果表明,在不显著改变纤维形态和结晶度的条件下,提高纤维聚合度可以显著提高薄膜的力学性能（抗张强度、韧性、耐折度、撕裂指数、耐破指数）,而其光学性能无明显的变化规律,透光率介于87.9%～89.8%,雾度介于53.6%～64.1%。     

浆料打浆度对纤维素薄膜光学及力学性能的影响

探究了磨浆工艺对纤维素薄膜光学及力学性能的影响。通过PFI磨浆机磨浆,得到打浆度分别为60°SR、70°SR、80°SR和90°SR的乌针浆,经疏解、真空抽滤和真空干燥等工艺,制备纤维素薄膜,并测试其透光率、雾度和力学性能。结果表明,通过PFI磨浆工艺改变乌针浆的打浆度,能够调节制备的纤维素薄膜的光学和力学性能。当乌针浆打浆度从60°SR提高到90°SR,制备的纤维素薄膜的结晶区尺寸从8.8 nm降低至8.6 nm,结晶度从64.3%降低至58.7%;透光率从35.7%提高到50.5%,雾度从97.8%降至94.5%;打浆度90°SR乌针浆制备的纤维素薄膜拉伸强度和拉伸应变分别达31.5 MPa和7.5%。     

聚乳酸/乙酰化纳米纤维素薄膜制备及性能研究

为改善聚乳酸(PLA)薄膜的力学及阻隔性能,采用纳米纤维素(NCC)对其进行改性。以微晶纤维素(MCC)为原料,用硫酸法制备NCC,进而制备乙酰化纳米纤维素(ANCC),然后将PLA与ANCC按不同比例混合后制备复合薄膜。采用透射电子显微镜(TEM)、傅里叶红外光谱仪(FTIR)、扫描电子显微镜(SEM)对其微观结构和形态进行观测。采用拉伸仪和氧气透过率仪对其力学和气体阻隔性能进行分析。结果表明,使用酸法制备的纳米纤维素长度为100~200 nm,直径范围为10~20 nm。乙酰化处理对纳米纤维素的外观形态没有明显改变。与纯聚乳酸膜相比,ANCC添加量为1%时制备的复合薄膜的拉伸强度增加了29.09%,进一步增加ANCC含量则会导致复合薄膜力学性能下降。添加ANCC有效降低了复合薄膜的氧气透过量,ANCC添加量为0.5%时,薄膜的氧气透过率与纯PLA薄膜相比降低42%。添加ANCC对于薄膜的透光率和雾度没有明显影响。     

CMC/木材纤维复合纸的制备及性能(摘要)

正乳液、石蜡、树脂等高分子聚合物浸入纸张制备复合纸,其抗水、力学以及光学性能得到了大幅度提升。本文以可生物降解的羧甲基纤维素(CMC)和桉木浆为原料,通过造纸法和浸渍工艺制备CMC/木材纤维复合纸,并探究了CMC的浸渍量对复合纸光学、力学性能的影响。溶解CMC准确称量10g CMC粉末,接着量取790m L蒸馏水加入烧杯,然后将其置于水浴锅中,加     

亚麻分层纳米纤维素的制备及其增强热电复合材料性能

为从天然亚麻纤维中制备出分层纳米纤维素(即纤维素纳米纤维(CNF)与纤维素纳米晶(CNC)共存),并对其制备方法进行优化完善,提出将亚麻纤维在特定浓度的氢氧化钠溶液中碱化处理后,再进行四甲基哌啶氮氧化物(TEMPO)介导的三元氧化和机械处理的联合处理方法。然后将亚麻CNF与石墨烯复合制备CNF/石墨烯复合薄膜并研究亚麻CNF增强热电复合材料的性能。结果表明:碱化预处理使亚麻纤维直径变细,长度变短,半纤维素被脱除,是生成不同尺寸CNF的重要步骤;随着氢氧化钠用量在0~18%范围内的增加,所得CNF悬浮液的光透过率从3.7%增加到95.1%;CNF/石墨烯复合膜表现出最高功率因子,为8.0×10 ^-3 μW/(m·K ²),表明复合薄膜具有热电性能。     

基于羧甲基化木质纤维的高雾度、高透明纸

以木质纤维为原料,首先对其进行羧甲基化改性,使纤维发生润胀;再将改性后的木质纤维通过抄纸工艺制备出具有优异热稳定性的高雾度、高透明纸。通过性能表征可知:其透明度达89%,雾度达85%(波长550 nm处),拉伸强度最高达到138 MPa,初始分解温度为279℃。有望进一步推动高雾度、高透明纸在电子器件领域的规模化应用。     

基于铸涂法的高透明纳米纸的高效制备工艺

以纳米纤丝化纤维素(NFC)为原料,采用铸涂工艺制备高透明纳米纸。首先,通过改变纳米均质的次数调控纳米纤维素分散体的理化性能(黏度、保水值和纤维尺寸)。其次,研究纳米纤维素分散体理化性能和纳米纸干燥参数对其干燥速率的影响规律,探究最佳干燥工艺,快速制备出高透明纳米纸。研究表明:随着均质次数的上升,纳米纤维素分散体的黏度、保水值以及纤维素直径呈现下降趋势,且这些理化性能对高透明纳米纸的干燥速率没有影响。当干燥温度为40℃,相对湿度为30%时,制备定量为30g/m~2的高透明纳米纸所需的时间小于5h。纳米纸的强度达到140MPa,表面粗糙度为3.13nm,在可见光区透光率约为90%。     

增强剂对大豆蛋白/聚乙烯醇复合薄膜性能的影响

以薄膜拉伸强度、断裂伸长率、透光率、吸水率为评价指标,通过隶属度函数综合评分方法,研究了增强剂对大豆蛋白/聚乙烯醇复合薄膜性能的影响。实验结果表明:与对照组相比,添加可溶性淀粉,薄膜吸水率显著降低,透光率明显增大,但薄膜拉伸强度和断裂伸长率略有减小;添加羧甲基纤维素钠(CMC-Na),薄膜拉伸强度和吸水率明显增大,断裂伸长率明显减小,透光率几乎没有变化;加入明胶,薄膜的拉伸强度增大不明显,断裂伸长率和透光率均有显著提高,吸水率明显减小,当明胶浓度为0.200%时,薄膜综合性能最佳,拉伸强度为4.69MPa,断裂伸长率为45.65%,透光率为13.78%,吸水率为47.21%。     

超细石墨再生纤维素复合纤维制备及性能研究

选择几种常见分散剂制备超细石墨粉体分散体系,并优选最佳分散剂。以再生纤维素溶液为基体,制备超细石墨再生纤维素复合纤维。详细介绍超细石墨再生纤维素复合纤维的制备方法,并对复合纤维的形态结构、红外光谱、X射线衍射曲线、热学性能进行测试分析。结果表明,羧甲基纤维素钠(CMC)对超细石墨粉体的分散效果最好;超细石墨再生纤维素复合纤维横截面呈锯齿状,纵向表面有沟槽,超细石墨粉体在纤维中分布均匀;超细石墨的加入导致纤维素纤维中原有化学键的比例下降,红外峰值降低;超细石墨与纤维素纤维基体具有良好的相容性;与常规纤维素纤维相比,超细石墨再生纤维素复合纤维的热稳定性更好。     

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.     

Review of techniques to manufacture micro-hydrogel particles for the food industry and their applications

Microgels are ‘soft’ microscopic cross-linked polymeric particles that are being increasingly exploited in a variety of industries for rheology control, encapsulation and targeted delivery. They are valued because of the ability to tune their functionality to address specific applications in oil recovery, coatings, drug delivery, cosmetics, personal care and foods. Food microgels are typically biopolymer hydrogels in the form of microspheres, nanospheres (also called nanogels), spheroids and fibres. The utilisation of engineered microgels in foods has so far been limited, despite their great potential to address several needs in the food industry, including: satiety control, encapsulation of phytonutrients and prebiotics, texture control for healthier food formulations (e.g. reduced fat products), and targeting delivery to specific areas in the digestive tract. We review the scientific and patent literature on the utilisation and manufacturing methods for producing microgels with an emphasis on micro-hydrogels for food applications.     

12—A CRITIQUE OF SOME HYPOTHESES RELATING TO THE HETEROGENEITY OF THE HIGH-SULPHUR PROTEINS OF WOOL

Joubert and Burns prepared a large number of fractions from the high-sulphur proteins of wool and estimated their molecular weights and amino-acid compositions. Their data have been re-examined in order to look for statistically significant interrelations between amino acids and between the proportion of various amino acids and molecular weight. Statistical analysis of the data is also used to examine the credibility of some hypotheses concerning the mechanism of keratin biosynthesis and to provide further evidence for the existence of families of proteins within the high-sulphur fractions of wool.     

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.     

Announcing a new international peer-reviewed journal:Food Science and Human Wellness now accepting manuscript submission in English

<正>We are pleased to announce the launch of a new international peer-reviewed journal-Food Science and Human Wellness,ISSN 2213-4530,which is an open access journal,produced and hosted by Elsevier B.V.on behalf of Beijing Academy of Food Sciences.Food Science and Human Wellness is an international peer-reviewed English journal that provides a forum for the dissemination of     

The Latest Data about Development of Chinese Printing Industry in 2013

In the 2014 China（Shanghai）International Printing Week,Director Wang Yanbin released the latest data about development of Chinese printing industry in 2013.According to statistics,in 2013,the total output value of Chinese printing industry exceeded 1trillion Yuan for the first time,reaching 1.03985 trillion Yuan.There were 105,000 printing enterprises in China,employees were 3.415 million.The total asset was 1.06247 trillion Yuan;     

The State Council Issued "Directory of Government Approved Investment Projects(2013 Edition)"

正On December 2nd,2013,the State Council issued the notification of"Directory of Government Approved Investment Projects(2013 Edition)"(hereafter referred to as"notification").It is pointed out in the"notification"that in order to further deepen reforms in investment systems and administrative examination and approval systems,simplify administrative procedures and delegate powers to lower levels,earnestly     

China textile machinery: taking off in progress

正Among the 1600 exhibitors who take apart in the ITMA ASIA+CITME2014 2/3 are Chinese manufactures.If the numerous figures failed to attract your attention,the increase of quality should draw your focus.To adopt the demand of developing textile machine market,domestic textile machinery enterprises now follow the slogan of"technology drives development"to enhance product competitiveness.Our domestic sellers will showcase product ranging from spinning,weaving,dyeing and printing,     

Top Ten News of China's Paper Industry 2013

On December 24th, 2013, the meeting on the selection of top 10 news of China＇s paper industry 2013 sponsored by 〈China Paper Newsletters〉 was held in Beijing. The yearly selection of the top l0 news, which began in 2000, has become a brand activity widely recognized in the industry thanks to the support from the authorities at all levels and public participation.