木质素中空纳米球的制备和应用研究进展

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。     

工业木质素的改性与应用研究进展

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     

木质素高值化利用最新研究进展

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。     

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。     

木质素/TiO2复合纳米颗粒合成及纳米纤维素基紫外屏蔽膜制备

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。     

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。     

羧乙基化和碱预处理玉米芯渣制备纳米纤维素的研究

玉米芯提取木糖后剩余的残渣富含纤维素和木质素,采用羧乙基化反应和质量分数1%的NaOH溶液分别对玉米芯渣进行预处理,再经机械解离制备了纳米纤维素,最后经棒涂法制得纳米纤维素膜,并对预处理前后玉米芯渣、纳米纤维素及其膜的化学结构、组分含量、微观形貌、尺寸分布、水接触角和热稳定性进行了分析和表征。结果表明,羧乙基化预处理可增加玉米芯渣的羧基含量,同时脱除部分木质素,而碱预处理可脱除大部分木质素。经预处理后,玉米芯渣纤维尺寸明显降低、可及度增加。经机械解离后,羧乙基化预处理所得纳米纤维素的直径更小、分布更均匀,其经棒涂法所得膜也更加致密平滑,水接触角较大。另外,两种预处理方法均降低了所得纳米纤维素膜的热稳定性。     

棉浆纳米纤维素的制备与表征

纳米纤维素由于其尺寸的优势,具有高强度、高纯度、高结晶度、高导电率、高比热容、高比表面积的优点而得到关注。针对棉浆粕丙酮抽提物对制备纳米纤维素的影响,实验通过应用气质联用对棉浆粕丙酮抽提物成分进行检测。利用硫酸法和机械法相结合的方式制备了纳米纤维素,考察了纳米纤维素制备过程中硫酸浓度、酸浆比、反应时间、反应温度、球磨等影响因素,通过正交实验得出较佳的工艺条件,并对制得纳米纤维素进行了表征。     

表面活性剂助溶体系自组装制备微/纳米木质素及其紫外线防护应用

以碱木质素为原料、不同表面活性剂溶液为溶剂,通过自组装法制备微/纳米木质素,初步探讨了在不同表面活性剂溶液条件下制备微/纳米木质素的最佳pH值、温度和木质素添加量.通过纳米粒度和Zeta电位测定仪、扫描电子显微镜、傅里叶变换红外光谱仪对制得的微/纳米木质素进行表征.结果表明,采用十二烷基硫酸钠制备的微/纳米木质素平均粒...     

旧报纸基含木质素CNC和CNF的综合制备与表征

本研究以旧报纸为原料,采用硫酸水解法制备了含木质素纤维素纳米晶体（LCNC）,随后利用超声辅助球磨法将酸解沉淀的木质纤维素固体残渣（LCSR）解纤成含木质素纤维素纳米纤丝（LCNF）,实现了LCNC和LCNF的综合制备,综合产率高达85%以上。采用多种手段对LCNC和LCNF样品的结构特性进行分析表征。结果表明,LCNC呈棒状晶体结构,LCNF呈长丝状结构,木质素以球状颗粒存在于LCNC和LCNF中。LCNC平均长度和宽度分别为143.6和24.8 nm,LCNF的平均直径为16.2 nm。X射线衍射仪（XRD）结果显示LCNC和LCNF均保留纤维素I型结构,且木质素含量越高,其结晶度越低。同时,木质素本身的高疏水性和热稳定性使得木质素含量大的LCNC和LCNF具有更好的疏水性和热稳定性。     

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.     

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     

INFOPRINT 2014 was Successfully Held in Dongguan

Sponsored by Printing and Printing Equipment Industries Association of China （PEIAC） and organized by Print China magazine, the Seventeenth Beijing International Printing Information Conference （INFOPRINT 2014） was successfully held on 11th Dec. 2014 at Dongguan Exhibition International Hotel.