Salen-卟啉配合物催化氧化DBDO木素模型物

为研究Salen-卟啉配合物催化氧化DBDO木素模型物,合成了DBDO木素模型物,以木素模型物为反应物。利用红外光谱和气相色谱-质谱(GC-MS)分析木素模型物在Salen-卟啉配合物催化氧化下的降解产物,依据催化氧化后的DBDO木素模型物降解产物,发现Salen-卟啉配合物的催化氧化能使DBDO木素模型物中Cα-Cβ、α-O-4、β-O-4联接断裂,并且使甲氧基减少,产生了香兰素、苯酚、苯甲醛等降解产物。     

4,4'-二氨基二苯胺-2-磺酸的合成及其结构表征

本文以2-氯-5-硝基苯磺酸和对苯二胺为原料,通过缩合和还原两步反应,合成了无致癌性染料中间体4,4'-二氨基二苯胺-2-磺酸.利用红外光谱、质谱、氢核磁共振谱对合成产物进行了结构表征.     

芳香族甜菜碱型加脂复鞣剂的合成与表征

通过对羟基苯磺酸、苯酚、单宁及甲醛的共缩合,以及缩合产物对环氧季氨盐的亲核开环反应,合成了带有C18烷烃链的芳香族甜菜型加脂复鞣剂。利用红外光谱（FT-IR）和差示扫描量热法（DSC）对中间物及产物结构进行了跟踪表征。结果表明：反应过程中官能团的变化证实了产物的合成,产物中C18烷烃链的引入导致Tm大大降低,起到了明显的内增塑作用。     

酚型木素模型物硫酸盐法蒸煮过程中LCC形成的研究

合成了带13C同位素标记的酚型木素模型物——愈创木基丙三醇-β-愈创木基醚-[α-13C],模拟了硫酸盐法蒸煮过程,将合成的木素模型物和典型的半纤维素组成部分——木糖进行蒸煮,然后利用酸析沉淀木素、乙酸乙酯抽提等方法将蒸煮后的产物分级,并利用13C-NMR(13C-核磁共振波谱)和二维HMQC(异核多量子相干谱)对分级后的各个部分进行分析,研究传统硫酸盐法蒸煮过程中LCC的形成情况。研究发现:酚型木素模型物的中间产物和木糖衍生物(糖醛酸等)形成了少量苯甲醚键型LCC结构,这些新形成的LCC结构主要存在于乙酸乙酯抽提物中。     

直接桃红B(C.I.直接红9)的合成研究

三聚氯氰与H酸单钠盐一次缩合反应得到一缩合物A,一缩合物A与脱氢硫代对甲苯胺单磺酸二次缩合反应得到二缩合物B,二缩合物B与邻氨基苯甲酸的重氮盐偶合后得到偶氮物C,偶氮物C再在碱性溶液中进行水解反应得到直接桃红B(C.I.Direct Red 9)。本论文对于一次缩合、二次缩合、偶合、水解反应的反应条件进行探讨,找出了直接桃红B适宜的合成反应条件。     

木质素改性皮革复鞣剂的制备与应用研究

木素磺酸先与甲醛、对羟基苯磺酸缩合,再与间苯二酚缩合,得到木素-甲醛-对羟基苯磺酸-间苯二酚缩合物(LFR).LFR与适量的甲醇、戊二醛反应生成LFR-戊二醛缩合物(LFRG resin).LFRG与铬(Ⅲ)作用形成络合物复鞣剂-Retannage LG.HN复鞣剂、GA复鞣剂作参比,将Retannage LG复鞣剂用于猪皮正面服装革做对比应用试验.经对比应用试验确定了性能最好的Retannage LG- J复鞣剂的合成条件.木素改性复鞣剂Retannage LG- J的各项基本性能达到了铬复鞣剂和戊二醛复鞣剂的水平.     

4,4′-二氨基二苯胺-2-磺酸的合成及其结构表征

本文以 2 -氯 - 5-硝基苯磺酸和对苯二胺为原料 ,通过缩合和还原两步反应 ,合成了无致癌性染料中间体4 ,4′-二氨基二苯胺 - 2 -磺酸。利用红外光谱、质谱、氢核磁共振谱对合成产物进行了结构表征。     

制革常见科技问题解答(18)

(续上期) 121.什么是合成鞣剂?如何分类? 答:通常,我们将由芳香族化合物经过缩合而成的缩合物的鞣剂称为合成鞣剂.合成鞣剂种类繁多,种类不同,鞣革性能也不一样,所得到的皮革的性能当然也就不同了.     

β-O-4型木素模型化合物的合成及其在GIF型仿酶降解体系中的变化(

研究了一种β-O4型木素模型化合物--4-(α-(2-甲氧基苯氧基)-乙酰基)-愈创木酚的合成方法,并利用薄层色谱(TLC)、红外光谱和核磁共振谱(1H-NMR)等手段对它们的化学结构进行了分析与确认.采用由Cu2+/吡啶/过氧化氢组成的GIF型仿酶系统对这一木素模型物进行仿酶降解,结合高效液相色谱(HPLC)及GC-MS等分析方法,分析了该β-O4型木素模型化合物在降解过程中的结构变化,并对这种仿酶降解的机理进行了探讨.研究结果表明通过利用过量愈创木酚和4-乙酰基愈创木酚的溴化物的反应并结合羟甲基化可以得到含α-羰基的酚型β-O4木素模型化合物.GIF仿酶降解体系对β-O4型木素模型物有较强的碎解能力,降解后产生较多的脂肪族小分子化合物,一部分成为香草醛、香草酸等低分子芳香族化合物,该结果可以说明此降解体系能有效导致β-O-4型木素模型化合物的各种类型的裂解反应.     

水溶性聚酯浆料的合成与性能

采用酯交换-缩合聚合方法合成了一种水溶性聚酯浆料,并利用红外光谱、核磁共振、X射线衍射、凝胶色谱等对其结构进行了表征,结果表明:在优化的合成工艺条件下,所制备的水溶性聚酯浆料为非结晶性共聚物,具有良好的粘度性能、成膜性能和浆纱性能.     

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