碳水化合物非酶催化转化为乳酸及乳酸酯的研究进展

本文概述了常规催化体系（均相和非均相）中Lewis酸（L酸）和Br?nsted酸（B酸）催化碳水化合物（三碳糖、五碳糖、六碳糖和纤维素）转化为乳酸/乳酸酯所涉及的主反应（如水解、异构、逆羟醛和氢转移等）和副反应（如脱水和缩合等）路径,以及催化剂结构与催化效率间的构效关系;综述了基于金属有机骨架（MOF）、锡基硅酸盐和石墨化的氮化碳材料构建新型非均相和光催化体系的研究进展;对复合功能型催化剂（含L酸、B酸、绑定基团和多级孔结构）的未来发展趋势进行了展望。     

生物质基多孔碳材料作为超级电容器电极的研究进展

生物质基多孔碳材料因原料来源广泛、价格低廉、环境友好等特点受到人们广泛关注,将其应用于超级电容器等储能器件可有效促进其在多领域实现高值化应用。本文通过深入分析近年来生物质基多孔碳超级电容器制备及应用的最新技术,从生物质原料种类、生物质基多孔碳材料的优化（活化和掺杂）及生物质基碳电极在不同超级电容器电极材料的应用等方面,归纳总结了生物质基多孔碳材料作为超级电容器电极未来面临的挑战。     

纳米纤维素碳气凝胶制备及其电催化性能研究

本研究以纤维素纳米纤丝(CNF)为碳骨架,氮含量高的类石墨相氮化碳(g-C₃N₄)为氮源和造孔剂,成功制备了一种具有分级多孔结构的氮掺杂碳气凝胶(NCA)电催化剂。研究了NCA的物理化学结构与氧还原反应(ORR)活性之间的关系,以及其锌-空气电池性能。该NCA催化剂表现出较高的比表面积(381.77 m~2/g)、分级多孔结构,氮掺杂含量3.27%。ORR测试结果表明,NCA具有优异的ORR催化活性,半波电位可达0.83 V,接近商业铂碳(Pt/C)电催化剂。进一步将NCA作为阴极催化剂用于组装水系锌-空气电池,在电流密度为10 mA/cm~2下可以实现长达110 h的循环充放电,具有良好的电池使用性能。     

莲子衍生氮掺杂碳的制备及其电催化氧还原反应性能

燃料电池和锌空气电池因具有清洁、高效等优点而被研究者们广泛研究。目前,Pt/C催化剂不耐甲醇且价格高。所以燃料电池和锌空气电池的商业化受到严重限制。来源广和催化ORR活性高的氮掺杂碳材料开始被关注,因此发展氮掺杂碳材料催化剂具有现实意义。通过热解莲子和氯化铵的复合物,制备了氮掺杂碳材料(pNC),并测试了其在碱性溶液中的电催化性能。最重要的是,pNC稳定性和抗甲醇性能均明显优于Pt/C。pNC作为阴极电催化剂所组装的锌空气电池也表现出了优异的电池性能。     

二硫化钼纳米材料在电催化方面的研究进展

文章基于二硫化钼的研究背景,首先对相关理论进行广泛搜索和整理,详细介绍了二硫化钼纳米材料在电催化方面的应用,包括析氢反应、析氧反应、水分解反应和氧还原反应,分析了纳米二硫化钼作为高效的电催化析氢催化剂这一热点最新的研究进展,以及纳米二硫化钼做催化剂所面临的机遇和挑战,为制备高性能的纳米二硫化钼电催化剂提供了思路。     

负载型碳基催化剂及其失活原因

自活性炭被发现可以催化过氧化氢产生大量自由基降解污水中的有机物质,碳材料便得到大量研究并应用于湿式催化氧化领域。本文将对负载型碳基催化剂进行简要介绍,尤其是对催化剂失活原因进行总结,促进碳基催化剂进一步推广应用。     

中科院研究木素催化转化获进展

正近日,中国科学院科学家团队——大连化学物理所研究员王峰带领的团队,在生物质催化转化利用方面取得系列进展:发展了一种碳修饰的Ni基催化剂,实现了木素选择性氢解到酚类化合物。木素作为一种储量丰富的生物质资源,占生物质资源的20%~30%,是自然界中唯一可以提供可再生芳香基化合物的     

染色废水的电解水-电芬顿耦合体系矿化处理

利用电解水阳极产生的副产物氧气为电芬顿反应持续供氧，开发了电解水-电芬顿耦合体系，并通过制备低成本的Ni/SnS2/芳纶电极代替传统电芬顿反应中昂贵的碳基电极，极大降低了电芬顿和分解水两项工艺的成本。对低质量浓度亚甲基蓝染液（5 mg/L）进行12 h的持续性降解，总有机碳去除率可达69.4%。该电解水-电芬顿体系具有普适性，对于其他电芬顿催化电极材料如泡沫镍、碳布等，总有机碳去除率同样可达到69%。该工艺实现了低浓度有机污染物的低成本、高效率矿化，通过分解水产生氢气，提升了反应产物的附加值，对工业化处理有机污染物表现出较好的应用潜力。     

四丁基溴化铵催化合成环氧大豆油

在无溶剂无羧酸条件下,以四丁基溴化铵为相转移催化剂,用65%的叔丁基过氧化氢(TBHP)为氧源直接合成环氧大豆油。考察了反应温度、反应时间、催化剂用量及TBHP与碳碳双键摩尔比对环氧化反应的影响,通过红外光谱对催化环氧化的机理进行了初步探究。结果表明:在反应温度65℃、反应时间3 h、催化剂用量3.0 g(10.0 g大豆油)、TBHP与碳碳双键摩尔比1.5∶1条件下,催化环氧化效果最好,环氧值、转化率和选择性分别达到3.5%、53.9%和77.5%。此方法操作简单,催化剂价格低,简化了工艺流程,降低了工艺成本,同时克服了传统方法使用羧酸和溶剂等造成的弊端。     

杂多酸催化合成马来酸(2-2乙基己基)酯的研究

杂多酸（ＨＷＰ）为催化剂,以顺丁烯二酸酐与仲辛醇为原料催化合成马来酸（２－２乙基己基）酯。研究了催化剂的用量、酯化、磺化反应时间、酸醇摩尔比对反应的影响,催化剂能使用多次催化效果较好。     

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.     

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