封端型水系聚氨酯交联剂的合成及其作用

以甲苯二异氰酸酯、异佛尔酮二异氰酸酯、二环己基甲烷二异氰酸酯及二羟甲基丙酸为原料,亚硫酸氢钠为封端剂分别合成了3种水溶性聚氨酯齐聚物交联剂(B-WPU)。通过红外光谱仪(FT-IR)、差热分析(DSC)分别对其结构和解封温度进行了表征。以明胶作为皮胶原模拟物,发现碱性条件下B-WPU与明胶反应后,明胶的总有机碳、总氮含量均明显增大,反应后明胶的热稳定性增强。将其作为一种预鞣剂使用,可将皮坯收缩温度提高到80℃左右。5%的齐聚物预鞣后再用4%铬粉鞣制,成革收缩温度高于110℃。进一步的电感耦合(ICP-AES)检测表明:废液中铬含量显著下降,铬的吸收明显提高,与常规铬鞣(7%铬粉)相比,可节省铬用量30%~40%。     

没食子酸与铬铝结合鞣制研究

在植物鞣剂与金属盐结合鞣制研究的基础上,以小分子的没食子酸代替大分子栲胶与金属盐结合鞣制,以收缩温度变化为考察指标,对没食子酸与铬鞣剂和铝盐鞣剂结合鞣制性能进行研究。结果表明:没食子酸具有一定的鞣性;用3%的没食子酸(山羊酸皮质量计)进行预鞣处理后,再用10%铝盐鞣制,收缩温度可达91.4℃。与同用量的铝盐鞣制坯革相比,收缩温度提高了23.7℃,证明了没食子酸与铝盐结合鞣制具有很好的协同鞣制效应。当没食子酸与铬鞣剂进行结合鞣制时,没食子酸对结合鞣制没有增效作用;用3%的没食子酸进行预鞣处理后,再用2%铬鞣剂和5%铝盐共同鞣制,可以使坯革收缩温度达到103.5℃,相对于酸皮提高了50.0℃,说明没食子酸对铬鞣剂和铝盐三元结合鞣有良好的增效作用。     

7-羟基全氢化恶唑并恶嗪在皮革工业中的应用

本文报导了新型鞣剂7-羟基全氢化恶唑并恶嗪(以下简称OX-Z)在皮革鞣制中的应用.OX-Z对浸酸绵羊皮单独鞣制可使收缩温度升高到87℃,最佳鞣制条件为:pH10.0,OX-Z用量5%,鞣制时间8h.先用5%OX-Z预鞣后,皮子再用4%的标准铬粉鞣制8h,其收缩温度可达到95℃以上.OX-Z与铬结合鞣的坯革其厚度、撕裂强度、规定负荷伸长率和断裂伸长率均有所增加,而抗张强度则有所下降.     

植—铝结合鞣法的研究(续)

讨论一、结合鞣革的收缩温度植物鞣革的收缩温度,一般在80℃左右,纯铝鞣革的收缩温度,一般在70℃左右,但实施植—铝结合鞣(先植鞣再铝盐复鞣或先铝鞣再植物鞣剂复鞣)后,成革的收缩温度却可大大提高,甚至可高达130℃左右,与鞣制良好的铬鞣革相似,这是除了铬鞣革以外其它革所不能达到的。对这种奇特现象的解释一般公认是铝盐与植物鞣质(根据鞣制工艺,其中之一先已与皮蛋白质结合)发生     

一种无盐免浸酸少铬鞣技术的研究

为了减少铬鞣剂的用量并提高裸皮对铬鞣剂的吸收率,减少其对环境的污染。本文以山羊软化裸皮为原料皮,先采用不浸酸铬粉对其进行预鞣制,然后采用y一般铬鞣剂对预鞣、削匀后的坯革进行再鞣制,随后对其进行染色加脂实验,先后测试不同阶段的革的收缩温度、坯革状态、吸收率及成品革纤维的形貌等。结果表明,最佳的方法是采用1.8%~2%不浸酸铬粉预鞣山羊软化裸皮,鞣制后所得的坯革收缩温度为84.7℃,颜色呈浅蓝色,随后采用3%的标准铬粉进行鞣制后,坯革的收缩温度为112.7℃,坯革颜色呈浅蓝色、粒面平细,裸皮对铬粉的吸收率为90%。染色加脂与传统铬鞣革相比较染料的吸收率与油脂的吸收率及革纤维的分散程度相似。     

亚硫酸氢钠封端多羧基聚氨酯助鞣性能的研究

异佛尔酮二异氰酸酯与酒石酸制备的预聚体用亚硫酸氢钠作为封端剂进行封闭后,得到一种小分子多羧基聚氨酯产物,研究了其作为铬鞣助剂对裸皮的耐湿热稳定性和浸酸膨胀性、铬鞣革坯收缩温度、鞣制废液中Cr2O3含量及铬鞣剂吸收率的影响。结果表明:该铬鞣助剂能够与皮胶原蛋白发生结合,可引入大量羧基,同时使裸皮胶原纤维得到初步固定,提高耐湿热稳定性,有效抑制裸皮在浸酸过程中的膨胀作用,依据其用量不同可以进行少盐或无盐浸酸;该助剂使用后,能使铬鞣革坯的收缩温度提高到113℃以上,铬鞣剂的吸收率提高到85%以上,鞣制废液中Cr2O3含量降低到2 215 mg/kg以下,而并且其用量的增加可以加强这种影响作用。     

无盐浸酸高吸收铬鞣方法的研究

将芳砜型鞣剂用于预鞣建立了无盐浸酸高吸收铬鞣的方法。研究结果表明，预鞣的最佳条件为，芳砜型鞣剂用量4％，pH值6.0，温度35℃，时间4h：预鞣皮的收缩温度可达68℃。在无盐浸酸后用5％的标准铬粉鞣制，铬鞣废液中的铬含量可降至0．2gCr2O3／1以下，得到的蓝湿革与常规铬鞣蓝湿革无明显差别。     

没食子酸与锆离子的相互作用及其鞣制性能研究

(1)利用紫外-可见光谱、红外光谱以及核磁共振氢谱等检测方法,研究了没食子酸(GA)和锆离子之间的相互作用。研究表明:没食子酸可以与锆离子发生配位反应,且没食子酸的酚羟基和羧基均与锆离子发生了配位反应。(2)以绵羊皮的收缩温度变化为考察指标,对没食子酸与锆盐结合鞣制性能进行研究。研究表明:没食子酸、氧氯化锆均具有一定的鞣性,但是鞣性较小;锆-GA结合鞣制和GA-锆结合鞣制,坯革收缩温度均有很大的提高。先使用7%没食子酸预鞣处理,再用6%锆盐鞣制提碱至pH值6.0,收缩温度可达到最高的93℃。先使用6%锆盐预鞣制,再用7%没食子酸鞣制提碱至pH值5.0,坯革收缩温度可达到最高的92℃。不同的鞣制顺序会导致达到最佳鞣制效果所需提碱的pH值不同,可能是因为鞣制过程中GA、锆离子及胶原纤维三者之间的相互作用有所差别。     

7-羟基全氢化恶唑并恶嗪在皮革工业中的应用

本文报导了新型鞣剂7-羟基全氢化恶唑并恶嗪(以下简称OX-Z)在皮革鞣制中的应用。OX-Z对浸酸绵羊皮单独鞣制可使收缩温度升高到87℃，最佳鞣制条件为：pHl0．0，OX-Z用量5％，鞣制时间8h。先用5％OX-Z预鞣后，皮子再用4％的标准铬粉鞣制8h，其收缩温度可达到95℃以上。OX-Z与铬结合鞣的坯革其厚度、撕裂强度、规定负荷伸长率和断裂伸长率均有所增加，而抗张强度则有所下降。     

活性氯有机鞣剂制备及应用

以三聚氯氰(CC)和赖氨酸(Lys)为主要原料,制备一种端羧基活性氯有机鞣剂(TLys)。作为皮革鞣剂用于绵羊酸皮鞣制,鞣制皮革收缩温度(Ts)可达78℃。以鞣制革Ts为主要指标,对TLys制备工艺和鞣制工艺进行优化。将TLys鞣制革用2%铬粉复鞣,Ts可升至107.8℃,坯革粒面光滑细致,手感丰满厚实。复鞣废液中残余铬含量为0.48g/L,铬鞣剂的用量及排放量显著减少。     

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.