木质素羟基化改性及其在聚氨酯合成中的应用

工业木质素主要来源于制浆和纤维素乙醇生物精炼的副产物,产量巨大;且木质素具有替代多元醇合成聚氨酯材料的应用潜力。对木质素进行羟基化改性,可以控制木质素分子质量和增加羟基含量,从而提高木质素的反应活性和在合成体系中的相容性,减少木质素在聚氨酯中的聚集,增加聚氨酯材料的微观均匀性,从而增强聚氨酯材料的机械性能;同时还可能赋予聚氨酯抗紫外、吸油、可降解等性能。本文对木质素基本理化性质进行简要介绍,重点介绍了目前国内外木质素羟基化改性方法的研究进展;最后探讨了木质素基聚氨酯合成领域的研究和应用前景。     

低共熔溶剂处理木质素抗菌纸的制备及性能研究

利用对甲苯磺酸/氯化胆碱（TA/CC）制备的低共熔溶剂（DES）处理碱木质素,提取得到富含酚类的木质素精油,将其添加到杨木浆中,制备了抗菌纸。结果表明,DES处理后得到的木质素精油中含有大量酚羟基,制得的抗菌纸对大肠杆菌的抗菌率约100%,在食品包装用纸、医疗用纸等领域具有较大的应用潜力。     

木质素基水凝胶材料的设计策略及应用进展

木质素是自然界中含量第二丰富的天然高分子聚合物,也是芳香族化合物中少有的可再生资源之一,作为制浆造纸行业的主要副产物,工业木质素价廉易得。鉴于木质素自身的三维网状结构及丰富的醇羟基、酚羟基、双键等活性官能团,其具备了抗菌、抗炎、吸附等诸多优势,是制备水凝胶的理想选材。但遗憾的是由于木质素结构复杂、空间阻力大、反应活性不足,其提纯处理较为困难、高值化和产业化利用水平较低。利用木质素及其衍生物制备水凝胶既拓宽了其应用范围,又能较好解决现阶段合成高分子水凝胶存在的生物相容性差等问题。基于此,本文从木质素的结构和性质出发、归纳了木质素基水凝胶材料的主要制备方法及优缺点,总结了其在生物医学、污水处理、农业、电子器件等方面的应用现状,并进一步提出了木质素基水凝胶材料现阶段研究中存在的局限性和今后可能的研究前景。     

木质素的生物降解及其应用

综述了具有降解木质素能力的微生物和酶的种类及其降解特性,阐述了木质素生物降解在生物化学制浆、纸浆生物漂白、造纸废水生物处理、饲料工业、生物肥料等领域的应用现状,展望了木质素生物降解技术研究的发展趋势.     

多糖基塑料研究进展

为解决不可降解塑料带来的环境污染问题,开发具有可降解特性的生物基塑料成为研究热点。天然多糖具有生物降解、生物相容和抗菌等特性,是制备可降解塑料的理想原料。但是由于天然高分子多糖具有较高的结晶度无法直接加工利用,且多羟基结构使多糖基材料在高湿环境下易吸湿导致性能下降。因此,制备高性能的多糖基塑料仍具有很大的挑战。本文综述了近年来采用纤维素、甲壳素和淀粉3种天然多糖为原料,通过分子工程和复合策略构建多糖基塑料的研究进展,为开发新型多糖基生物可降解塑料提供理论基础和研究思路。     

废弃香烟过滤嘴辅助增强木质素微波解聚特性

木质素微波解聚存在转化效率偏低、二次反应剧烈等问题。本研究通过在木质素中添加一定比例的废弃香烟过滤嘴(UCF)颗粒来辅助增强木质素的快速解聚和调控产物组分分布。结果表明,随着UCF添加量的增大,生物油产率逐渐增加,生物炭产率呈下降趋势。与理论产率相比,UCF的加入更有利于生物油和生物炭的生成。对生物油化学成分定量分析发现,UCF的加入能够通过脱甲氧基或脱羟基作用来降低愈创木基酚类化合物的产量。当UCF添加量为60%(相对于木质素)时,对羟苯基酚类化合物(127.53 mg/g)和芳香烃类物质(22.28 mg/g)的产量达到最高。对固体产物分析发现,生物炭比表面积随着UCF添加量的增大而逐渐增加,同时UCF加入能够形成炭纤维结构并在木质素炭上附着和生长。本研究发现UCF和木质素在微波解聚过程中发生了显著的协同效应,对于木质素的高效转化和废弃资源高值化利用具有积极意义。     

木质素/PBAT复合材料的性能提升与应用研究进展

木质素作为可再生自然资源,具有多种高附加值的功能特性,将其与可生物降解高分子聚合物复合是其转化利用的重要途径之一。然而,木质素的异质性限制了其在复合材料中的开发和利用,采取针对性的策略和方法生产高附加值的木质素基可生物降解复合材料至关重要。本文主要阐述了高性能木质素/聚己二酸/对苯二甲酸丁二酯（PBAT）复合材料的不同制备策略,如添加增容剂、木质素的溶剂分级、纳米化和化学改性等,进一步总结了该复合材料在紫外屏蔽、水蒸气/氧气阻隔和抗菌等方面的潜在应用,并对木质素/PBAT复合材料所面临的挑战和未来发展方向进行总结和展望。     

木棉纤维性能及其在纺织中应用的建议

总结木棉纤维的性能特点。分析了木棉纤维的形态结构、化学组成及物理性能。指出高木质素含量赋予木棉纤维天然抗菌、吸水快干、亲油、扭转刚度大的特性;高半纤维素含量使得木棉制品具有高吸湿、不耐紫外辐射等性能;高中空度使得木棉制品具有质轻、保暖、吸声等优良特性。建议木棉纤维加工工艺应该参照苎麻纤维加工工艺、避免高压,充分利用其抗菌、吸声、高浮力、高吸油等特性开发具有自身特色的纺织品。     

木质素改性化学品及高值化利用

木质素的化学改性方法主要分为3类,包括木质素裂解、合成新的化学活性位点和羟基功能化,这些方法为木质素在聚合物中的应用提供了新的思路。本文总结了木质素作为农用材料在化肥、植物生长调节剂、农药方面的应用;作为生物医学材料在组织工程和DNA传递方面的应用;以及作为智能材料在生物传感和形状可编程材料领域应用的研究进展。     

木质素纳米颗粒的可控制备及应用进展

木质素纳米颗粒兼具纳米粒子和木质素分子的结构特性,具有广泛的应用领域。本文综述了木质素纳米颗粒的机械法(包括高压均质法、超声波法、组合法)、纳米沉淀法(包括自组装法、酸沉淀法、透析法)、界面交联与乳液法和生物法的制备方式,并介绍了木质素纳米颗粒在抗菌剂、抗氧化剂、紫外线吸收剂、药物运输载体、纳米填料、催化和传感等方面的应用进展,展望了木质素纳米颗粒的发展方向。     

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.     

An internet compendium of analytical methods and spectroscopic information for monomers and additives used in food packaging plastics

An internet website (http://cpf.jrc.it/smt/) has been produced as a means of dissemination of methods of analysis and supporting spectroscopic information on monomers and additives used for food contact materials (principally packaging). The site which is aimed primarily at assisting food control laboratories in the European Union contains analytical information on monomers, starting substances and additives used in the manufacture of plastics materials. A searchable index is provided giving PM and CAS numbers for each of 255 substances. For each substance a data sheet gives regulatory information, chemical structures, physico-chemical information and background information on the use of the substance in particular plastics, and the food packaging applications. For monomers and starting substances (155 compounds) the infra-red and mass spectra are provided, and for additives (100 compounds); additionally proton NMR are available for about 50% of the entries. Where analytical methods have been developed for determining these substances as residual amounts in plastics or as trace amounts in food simulants these methods are also on the website. All information is provided in portable document file (PDF) format which means that high quality copies can be readily printed, using freely available Adobe Acrobat Reader software. The website will in future be maintained and up-dated by the European Commission's Joint Research Centre (JRC) as new substances are authorized for use by the European Commission (DG-ENTR formerly DGIII). Where analytical laboratories (food control or other) require reference substances these can be obtained free-ofcharge from a reference collection housed at the JRC and maintained in conjunction with this website compendium.     

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.     

Analysis of benzo[a]pyrene in spiked fatty foods by second derivative synchronous spectrofluorimetry after microwave-assisted treatment of samples

A simple, rapid and inexpensive method has been developed for the determination of benzo[a     

The development of reference materials for paralytic shellfish poisoning toxins in lyophilized mussel. II: Certification study

This paper describes the second part of a project undertaken to develop certified mussel reference materials for paralytic shellfish poisoning toxins. In the first part two interlaboratory studies were undertaken to investigate the performance of the analytical methodology for several PSP toxins, in particular saxitoxin and decarbamoyl-saxitoxin in lyophilized mussels, and to set criteria for the acceptance of results to be applied during the certification exercise. Fifteen laboratories participated in this certification study and were asked to measure saxitoxin and decarbamoyl-saxitoxin in rehydrated lyophilized mussel material and in a saxitoxin-enriched mussel material. The participants were allowed to use a method of their choice but with an extraction procedure to be strictly followed. The study included extra experiments to verify the detection limits for both saxitoxin and decarbamoyl-saxitoxin. Most participants (13 of 15) were able to meet all the criteria set for the certification study. Results for saxitoxin.2HCl yielded a certified mass fraction of <0.07 mg/kg in the rehydrated lyophilized mussels. Results obtained for decarbamoyl-saxitoxin.2HCl yielded a certified mass fraction of 1.59+/-0.20 mg/kg. The results for saxitoxin.2HCl in enriched blank mussel yielded a certified mass fraction of 0.48 +/- 0.06 mg/kg. These certified reference materials for paralytic shellfish poisoning toxins in lyophilized mussel material are the first available for laboratories to test their method for accuracy and performance.     

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     

Chinese CTP Market

According to Printing and Printing Equipment Industries Association of China（PEIAC）＇s statistics to the plate manufucturer in China, in 2013, the actual offset plate production has reached 346 million square meters in China. Among them, the CTP production volume was 245 million square meters, up by 11% than that of last year; the total sales of the CTP plate was 239 million square meters, up by 13%.     

Preparatory Work of Print China 2015 is Going Smoothly

正Held at Guangdong Modern International Exhibition Center,Print China 2015 will cover 7exhibition halls,besides the original Hall No.3,4,5,6,7,the newly built F zone of Hall 3 will be used too.The total area will be140,000 square meters.Hall 3:Offset and large printing equipment,package printing equipment,post press