木质素基碳材料的制备与应用研究综述

从制备、结构和应用总结了木质素材料的最新进展。现在只有少数分离的木质素被用作原料,因此文章详细综述了三种木质素基碳材料的制备方式以及应用制备方向,对其进行了总结,以了解当前木质素基碳材料的近况发展。具体而言,深入讨论了木质素不同制备方法的程序,包括活化、纺丝和模板法,以及稳定和碳化,以期全面了解木质素基碳材料的形成。其中对于目前各种碳材料的制备方法以及优缺点进行了简单的总结。最后对于未来木质素材料的发展方向和利用进行了展望。     

木质素基紫外阻隔膜材料的研究进展

本文基于与纤维素、可降解塑料和其他聚合物材料复合的3种木质素复合材料体系,总结了木质素基紫外阻隔膜材料的研究进展。阐述了木质素分子结构与紫外吸收性能的相关性,以及其对复合材料光稳定性、力学强度和阻隔性能等方面的影响。对木质素在不同复合膜材料体系中的提升机制和膜材料的功能应用进行了讨论。此外,基于木质素的紫外吸收等功能特性,对其在多功能复合膜材料的开发和潜在应用进行了展望,为木质素高值转化和利用提供一定参考。     

4种常见木质素有机溶剂法分级的研究进展

随着对木质素基生物质材料开发和研究的逐渐深入,进一步提高木质素基生物质材料的性能,需对木质素原料进行结构分级。有机溶剂法分级是一种可以获得具有特定理化性质木质素的简单可行的分级方法。本文总结了近年来采用有机溶剂法,对硫酸盐木质素、有机溶剂木质素、碱木质素和酶解木质素4种常见木质素进行分级,且分级效果较好的研究成果,利用分子质量及分子质量分布,以及醇羟基、酚羟基、甲氧基等官能团含量作为分级评价指标,比较了不同分级策略所使用的单一或多种有机溶剂的分级特点和优缺点,并对木质素分级研究作简要总结和展望。     

木质素基吸附材料的研究进展

木质素结构中含有芳环、脂肪族侧链和许多活性官能团,具有一定的离子交换与吸附性能.工业木质素主要源于制浆造纸业的副产物,通过改性可以制备各种功能不一的木质素基吸附材料.本文综述了木质素的吸附性能和国内外木质素基吸附材料的研究进展,分析存在的问题和难点,探索今后的研究方向.     

木质素基水凝胶的应用研究进展

木质素是世界上含量仅次于纤维素的生物聚合物,也是地球上可供人类利用的最丰富的芳烃资源。木质素丰富的官能团也为其高值利用提供了可能。本文从木质素基水凝胶最新的发展动态展开,综述当前木质素基水凝胶的制备方法、应用领域及发展状况,具体介绍了木质素基水凝胶在生物医药、传感应变及吸附等较为热门领域的最新研究成果。     

生物基吸附剂的研究现状与进展

综述了纤维素、淀粉、木质素、壳聚糖、果胶、瓜尔胶及农林废弃物等生物质材料及其衍生物在吸附领域的研究现状,根据被吸附物性质的差异,对不同生物质材料的改性方式及吸附性能进行分析和比较;结合当前生物基吸附剂的研究现状,提出了有待解决的问题,并对未来发展趋势进行展望,以推进生物基吸附剂的研究和发展。     

木质素基非异氰酸酯聚氨酯的研究进展

聚氨酯（PU）是用途广泛的聚合物材料之一。目前,以生物质资源为原料,合成非异氰酸酯聚氨酯（NIPU）的技术受到越来越多的关注。木质素是自然界中储量丰富的天然可再生芳香族聚合物,功能化木质素可用于替代不可持续的石油基原料,开发高附加值的NIPU产品。本文综述了近年来以木质素为原料合成NIPU的方法和策略,介绍了利用木质素及其功能化衍生物合成木质素基NIPU的研究进展,并展望了木质素基NIPU在泡沫材料、木材黏合剂、弹性体、涂料等相关领域的应用潜力。     

木质素基超级电容器碳电极研究进展

超级电容器是功率密度高、充放电速度快和安全可靠的绿色储能装置,其电极材料是超级电容器性能优劣的关键。可再生木质素具有含碳量高、来源广泛和成本低等优点,其通过活化、模板和纺丝等方法可制备出性能优异的木质素基超级电容器碳电极,具有较好的发展前景。本文主要介绍了木质素基超级电容器活性炭电极、模板炭电极和碳纤维电极,并对木质素基超级电容器碳电极的研究进行总结与展望,为新型高性能超级电容器电极材料的结构设计与制备提供参考。     

木质素应用及其球形颗粒特性研究进展

木质素作为一种可广泛获得的生物质资源,在高附加值化学品、纳米材料和生物质基材料中具有巨大的应用潜力。作为地球上含量丰富的天然高分子,木质素虽然在传统的制浆造纸业中属于副产物,但其在环保、可持续性及生物可降解产品的开发中显示出巨大的潜力。本文主要对木质素的化学结构、表征与分离方法,及其在不同工业领域的应用（如分散剂、黏合剂、涂料和复合材料）尤其是球形木质素的应用等方面进行综述,并对未来木质素相关研究方向进行了展望。     

木质素基pH敏感智能材料研究进展

随着科技发展,开发木质素基智能材料以满足日益增长的科技需求成为当下木质素基材料研究的重要分支。其中,木质素基p H敏感智能材料是近年来发展起来的新型材料,其结构、形状或性能会随体系pH值的变化而变化。这一性能在新材料领域具有潜在的应用前景。本文综述了木质素基pH敏感智能材料在生物质精炼、制药、制动器、木质素分级等领域的研究进展,提出该材料研发及应用中的现存问题,并展望其研究前景和工业应用进展。     

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.     

Chlorohydrins of bisphenol A diglycidyl ether (BADGE) and of bisphenol F diglycidyl ether (BFDGE) in canned foods and ready-to-drink coffees from the Japanese market

BADGE.2HCl and BFDGE.2HCl were determined in 28 samples of ready-to-drink canned coffee and 18 samples of canned vegetables (10 corn, 5 tomatoes and 3 others), all from the Japanese market. HPLC was used as the principal analytical method and GCMS for confirmation of relevant LC fractions. BADGE.2HCl was found to be present in one canned coffee and five samples of corn, BFDGE.2HCl in four samples of canned tomatoes and in one canned corn. No sample was found which exceeded the 1mg/kg limit of the EU for the BADGE chlorohydrins. However the highest concentration was found for the sum of BFDGE.2HCl and BFDGE.HCl.H₂O at a level of 1.5mg/kg. A Beilstein test confirmed that all cans containing foods contaminated with BADGE.2HCl or BFDGE.2HCl had at lest one part coated with a PVC organosol.     

European priorities for research to support legislation in the area of food contact materials and articles

A strong science base is required to underpin the planning and decision-making process involved in determining future European community legislation on materials and articles in contact with food. Significant progress has been made in the past 5 years in European funded work in this area, with many developments contributing to a much better understanding of the migration process, and better and simpler approaches to food control. In this paper this progress is reviewed against previously identified work-areas (identified in 1994) and conclusions are reached about future requirements for R&D to support legislation on food contact materials and articles over the next 5 or so years.     

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.     

Detection of adulteration of locust bean gum with guar gum by capillary electrophoresis and polarized light microscopy

Capillary electrophoresis (CE) and polarized light microscopy (PLM) were utilized in the detection of the adulteration of locust bean gum with guar gum. For CE analyses, standards of locust bean and guar gums were extracted with 30% CH₃CN, removing the residual proteins from the gum matrix. A 8.75 mM NaH₂PO₄-20.6 mM Na₂B₄O₇ buffer, pH 9, was used to separate these proteins and to identify marker proteins that were present in the guar gum. These markers did not co-migrate with components in the extracts of mechanically processed locust bean gum, and are used as indicators of adulteration. Using PLM with toluidine blue and iodine staining techniques, unadulterated locust bean gum samples were distinguished from mixed samples through the differential staining of components in locust bean versus guar and tara gums. These experiments in the use of CE and PLM provide orthogonal and complementary methods for the verification of 'true' positives and the elimination of 'false' positives.