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1.
木质素纳米颗粒结构和形态多样、绿色环保且可生物降解,其功能性开发和利用受到了广泛关注。受原料及生产工艺的影响,木质素结构差异较大,相应地影响了其纳米颗粒形态、尺寸、稳定性和化学性质等。本文综述了近年来木质素纳米颗粒的制备方法及其性能和应用的研究进展,重点介绍了木质素的结构特征对木质素纳米颗粒形态与功能性的影响,探讨了木质素纳米颗粒在增强纳米复合材料、紫外屏蔽材料、生物医学材料及食品包装等方面的应用,为其在高附加值生物基材料方面的开发提供一定参考。  相似文献   

2.
木质素中空纳米球是一种具有球形和独特中空结构的纳米颗粒,具有高的比表面积、生物相容性和高负载能力等特点,在生物医学、紫外防护、新能源等领域具有广阔的应用前景。本文针对自组装制备木质素中空纳米球的过程进行剖析,总结了近年来国内外溶剂-反溶剂法、界面细乳聚合法、模板法和交联/偶联聚合法等自组装方法制备纳米颗粒的形成过程与机理,以期对开发简单可控的自组装方法制备木质素中空纳米球、高效资源化应用提供借鉴。  相似文献   

3.
正通过分离纯化工业木质素,准确测定木质素的理化参数并进行构象拟合,同时深入探究木质素的聚集和解聚机理,在此基础上对木质素进行微结构调控和化学改性,制备不同结构的木质素基两亲聚合物,通过自组装和相转变调控等方法,制备木质素纳米颗粒并探索在不同领域的应用,进一步提升木质素的附加价值,同时不断开拓木质素的应用新领域。随着社会的发展,对资源与能源的需求不断增大,不可再生的化石资源日趋枯竭;同时,开采和利用化石资源造成的生态破坏和环境污染日益严重。生物质资  相似文献   

4.
因木质素结构复杂且类型繁多,使得木质素一直难以实现高值化利用。本文结合最近五年木质素高值化利用的研究文献报道,综述了木质素在阻燃材料、吸附材料、光电材料及医用材料等方面应用的可行性,以期为木质素制备高附加值产品提供指导。  相似文献   

5.
木质素纳米颗粒的可控制备及应用进展   总被引:1,自引:1,他引:0       下载免费PDF全文
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。  相似文献   

6.
本研究利用碱木质素作为生物模板诱导剂,通过水热法成功合成了一种具有良好紫外屏蔽性能的木质素/TiO_2复合纳米颗粒。结果表明,木质素/TiO_2复合纳米颗粒具有锐钛矿晶型、良好的纳米粒径和热稳定性。同时,证实了木质素的含氧官能团和TiO_2表面羟基发生类酯化反应,从而使木质素与TiO_2形成包覆嵌顿式结构的复合材料。在此基础上,研究了木质素/TiO_2复合纳米颗粒与纳米纤维素水凝胶制备薄膜材料的抗紫外性能。结果表明,添加质量分数10%的木质素/TiO_2复合纳米颗粒的纳米纤维素薄膜在全紫外线波段(200~400 nm)吸收了约90%的紫外线,表明木质素/TiO_2复合纳米颗粒具有良好的紫外屏蔽能力。  相似文献   

7.
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。  相似文献   

8.
本研究以玉米秸秆、杨木及松木为原料,利用不同液比的甲酸与原料(1∶10,1∶9,1∶8和1∶7)制浆,从制浆黑液中分离得到甲酸木质素,进一步制得甲酸木质素纳米颗粒,探究了不同甲酸木质素的酚羟基含量差异。结果表明,3种原料甲酸木质素具有木质素的基本结构特征,液比1∶9时制得3种原料甲酸木质素酚羟基含量分别为2.69、2.82、3.09 mmol/g。水接触角实验结果表明,3种原料甲酸木质素压片具有较强的亲水性。将甲酸木质素纳米颗粒用于制备甲酸木质素纳米颗粒/淀粉复合膜,复合膜的水接触角显著增加,其疏水性能与甲酸木质素的原料种类和制浆液比有关。经4个月老化后,复合膜的疏水性能进一步增强,3种原料甲酸木质素纳米颗粒/淀粉复合膜的水接触角最高分别可达127.2°、125.1°和123.5°。研究结果对增强木质素的疏水性能及扩展疏水性膜材料的应用具有积极意义。  相似文献   

9.
木质素作为自然界最丰富的可再生芳香族资源,由于具有复杂的三维网状结构和顽固的抗性,难以高值化利用。全球约有90%的工业木质素被直接用于燃烧发电,造成了极大的资源浪费。木质素氧化解聚转化为芳香族化合物是对其高值化利用的重要手段,本文在介绍木质素结构和种类的基础上,综述了木质素氧化解聚的研究进展,主要从化学催化氧化、电化学氧化、生物催化氧化解聚木质素的方法和氧化解聚产物4个方面进行总结,分析了各种氧化解聚方法的优缺点和适用范围,以及不同氧化解聚方法对木质素衍生产物的选择性影响。  相似文献   

10.
木质素磺酸盐具有良好的水溶性、高电负性及高表面活性等特性,被广泛应用于多个工业领域,是实现工业化应用的木质素基化学品之一。本文综述了木质素的磺化方法及木质素磺酸盐的分离纯化方法,进一步介绍其在染料分散剂方面的应用,提出了当前在木质素磺酸盐研究中存在的问题,并对其研究方向和工业应用前景进行展望,以期为木质素磺酸盐产品的高值化利用提供参考借鉴。  相似文献   

11.
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.  相似文献   

12.
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.  相似文献   

13.
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.  相似文献   

14.
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.  相似文献   

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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.  相似文献   

18.
<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  相似文献   

19.
《印刷工业》2014,(11):95-95
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%.  相似文献   

20.
《印刷工业》2014,(8):103-103
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  相似文献   

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