轻革复鞣

复鞣在制革工艺中日益显得重要。一般说来复鞣有以下好处:1.改善身骨,使皮革柔软,手感丰满;2.使粒面光滑,紧密,毛孔清晰;3.提高皮革均匀性,减少甚至消除松壳,缩小部位差;4.改善磨革性能;5.对铬鞣革有漂白作用,提高皮革耐光性;6.改善染色和加脂性能,使染料和加脂剂吸收均匀,结合牢固。7.提高皮革强度及贮存性。常用的复鞣剂大致有以下几类: 一、矿物鞣剂:普遍使用的是经过蒙囿     

喷浆机在坯革表面上浆量均匀性的分析

一、前言用于皮革涂饰的机器设备,目前有涂刷机、淋浆机、喷浆机三种。其中喷浆机适用范围最广,且涂层厚度易于控制,在皮革涂饰中最为普遍。然而喷枪对坯革表面喷涂的不均匀性,对现有的喷浆机来说,都还没有得到解决。这种不均匀性给涂饰质量造成不良的影响,同时浪费了相当数量的浆料。为了对现有喷浆机构的喷涂均匀性加以比较,并考查克服不均匀性的方法,对四种常见机构在坯革表面上浆量的分布进行了探讨。本文仅就分析结果作一概略介绍。     

影响猪面革丰满性的因素

皮革的丰满性是评定皮革质量的主要感观指标,它能反映皮革的穿着舒适、经久耐用和保持形态等性能。皮革的丰满性与皮革的多孔性有关,孔隙小,分布均匀,丰满性好。也就是说皮革纤维分散越好,纤维束之间间隙越小,皮革质地致密均匀、不空松、不板硬、丰满性好。近几年来,对猪皮的身骨研究较多,涉及许多工序,认为影响革身丰满、柔软和弹性的因素很多,在鞣前湿加工过程中,生皮经过酸、碱、盐、酶的作用,胶原纤维得以     

牛面革复鞣工艺研究

针对复鞣过程能改善皮革的丰满性、填充性、柔软性、上染性和渗透性等皮革性能的特点 ,对牛面革的复鞣作了以下研究 :a植物鞣剂复鞣 ;b植物鞣剂与合成鞣剂结合复鞣。研究结果表明 :采用植物鞣剂和合成鞣剂结合鞣法 ,能体现多种鞣剂性能 ,使成革具有更好的性能 ,且通过调整中和 ,可使复鞣剂在革中分布均匀。     

涂饰过程中油蜡的使用对皮革性能的影响北大核心

选取了斯塔尔公司的油蜡材料FI-50、FI-58、FI-306,对全粒面和修面牛皮的进行涂饰,研究涂饰中不同油蜡用量对皮革卫生性能、染料结合牢度等性能的影响。对比发现,涂饰中油蜡材料的使用会导致全粒面和修面革透水汽性、透气性的显著降低,皮革的防水性有所上升,耐干湿擦色牢度均有明显降低,并且随涂饰中油蜡用量的增加,这种影响会进一步增大。此外,全粒面和修面革对比发现,修面革具有更优的透水汽性、透气性,并且具有更佳的防水性。     

涂饰过程中油蜡的使用对皮革性能的影响

选取了斯塔尔公司的油蜡材料FI-50、FI-58、FI-306,对全粒面和修面牛皮的进行涂饰,研究涂饰中不同油蜡用量对皮革卫生性能、染料结合牢度等性能的影响。对比发现,涂饰中油蜡材料的使用会导致全粒面和修面革透水汽性、透气性的显著降低,皮革的防水性有所上升,耐干湿擦色牢度均有明显降低,并且随涂饰中油蜡用量的增加,这种影响会进一步增大。此外,全粒面和修面革对比发现,修面革具有更优的透水汽性、透气性,并且具有更佳的防水性。     

热氧老化对无铬鞣革物理性能的影响

皮革在一定湿度下进行热氧作用后,组织结构会逐渐发生物理化学上的变化,致使皮革商品丧失使用价值。模拟热氧老化处理,测定老化前后无铬鞣革物理性能参数的变化,对比观察老化前后革内纤维组织的差别。试验发现:4种无铬鞣法的革坯在老化前后变化的趋势,难以用统一的规律描述。醛植结合鞣革老化后,抗张强度和撕裂强度增加,其它3种革强度下降;负荷伸长率、柔软度也有升降不同的差异;老化后皮革的收缩温度(Ts)和崩裂强度均下降;老化后合成鞣剂和植铝鞣法革坯的透水汽值增大,另外2种鞣法革坯的透水汽值下降。扫描电镜下发现,老化后革纤维规整性降低。     

三 皮革涂饰剂的组成和应用

一、导言涂饰是皮革整理的一个主要过程,其任务为:①在皮革的粒面上涂上适当的溶液(涂饰剂),给予革所需的商品性能;②在由低级原料皮仿制高级皮革时于磨面的革上创造人造粒面层。这一过程的具体目的可概括为: 1.由于革粒面伤残、染料吸收不良等,使得苯胺染料所染颜色常不均匀,要借助于涂饰使革全批全面颜色变均匀。 2.于革的粒面上形成保护层,使革不受外界的作用。 3.给予革的粒面以光泽、耐水性、和美好外貌。     

名卉皮草设计做工受青睐

PU饰面皮革是把天然皮革的二三层内革、残次革经特殊的制膜贴压膜工艺方法处理，在皮革表面覆盖聚氨酯PU面层而成．这使皮革表面呈现出各种颜色、多种花纹，并且不失皮革透气、耐折的优点．在外观和防水性上有其独特之处。     

国内皮化产品简介

TR-1加脂剂是利用造纸工业副产品-塔尔油加工改性而制得的皮革加脂剂。可用于各种轻重革的加脂。乳液稳定性强,在PH5～10范围内对酸、碱、盐、铬液及植物鞣液都很稳定,该加脂剂在革上分布均匀、渗透良好。可提高皮革的丰满性,并且不会发生油斑。     

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.     

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