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1.
对阴、阳离子型铬鞣剂结合鞣制工艺进行研究,探索一种两步法无盐浸酸的铬鞣工艺。先用2%(以灰皮质量计)的不浸酸铬鞣剂SF-1对绵羊软化裸皮进行预鞣及酸液处理,再用4%的AB铬粉对坯革进行常规铬鞣。与常规铬鞣工艺相比:在总铬粉用量均为6%的条件下,两步法铬鞣废液中的Cr_2O_3含量为1 020.3mg/L,低于常规浸酸铬鞣废液中的Cr_2O_3含量3 160.2mg/L,且鞣制后坯革中铬的分布更加均匀。两步法铬鞣坯革的抗张强度和撕裂强度均能达到国家标准,并优于常规浸酸铬鞣工艺;通过环境扫描电镜观察证实两步铬鞣的坯革粒面平细,纤维分散程度较为均匀。  相似文献   

2.
简述了铬鞣废液的循环利用方法及其优缺点;提供了一种新的铬鞣废液有效回用于复鞣的工艺,复鞣废液Cr2O3含量低于0.1g/L,可直接排放,能实现铬鞣废液的封闭循环有效利用。  相似文献   

3.
对宝斯卡铬鞣废液封闭循环工艺技术应用的操作液进行了特征分析检测,并与常规铬鞣废液进行对比。分析结果表明:铬鞣废液封闭循环过程中的操作液中的六价铬被完全抑制,废液中Cr_2O_3、总有机碳、COD_(Cr)和氨氮等含量指标随循环次数的增加趋于累积平衡。研究结果揭示了铬鞣废液封闭循环工艺操作液的变化特征及技术的可行性与安全性,效益评估计算显示该工艺技术可明显节约水资源,减少中性盐和铬鞣剂的用量,经济与环境效益显著,具有良好的推广应用前景。  相似文献   

4.
对比了常规浸酸、甲基磺酸浸酸、芳香族磺酸无盐浸酸三种浸酸方法对铬鞣效果的影响,研究了三种铬鞣废液直接循环利用过程中废液中铬含量、氯离子等的变化及其对铬鞣效果的影响.结果表明,与常规浸酸-铬鞣工艺相比,甲基磺酸和芳香族磺酸浸酸铬鞣均能使铬鞣废液铬质量浓度从1142 mg/L降低到153.5 mg/L以下;铬鞣废液被直接循...  相似文献   

5.
基于系列有机酸配体与Cr~(3+)配合物的稳定性规律,制备了皮革铬吸收促进剂,并将其应用于铬鞣工艺中,通过废液中Cr_2O_3含量的测定评价铬吸收促进剂的应用效果;测试皮革的收缩温度、增厚率、物理机械强度、Cr_2O_3分布,说明铬吸收促进剂对皮革物化性能的影响。结果表明:与常规铬鞣相比,当加入皮革铬吸收促进剂2%~3%时,废液中Cr_2O_3含量至少减少了85%,可降低到0.10 g/L以下,即是铬鞣废液中的铬几乎被吸尽,说明铬吸收促进剂能大大提高铬的吸收和利用率,降低废液中Cr_2O_3含量。此外,铬吸收促进剂可提高皮革的丰满性和收缩温度,改善成革的物理机械性能。  相似文献   

6.
采用两性三聚氰胺树脂、改性戊二醛、铬鞣剂等设计皮革少铬结合鞣正交试验,以结合鞣所得的蓝湿革收缩温度、撕裂强度、粒面平细度以及鞣制废液的铬含量、COD含量为评价指标,优化少铬鞣黄牛鞋面革鞣制工艺。研究结果表明:采用2%两性三聚氰胺树脂、1%改性戊二醛依次对黄牛浸酸皮进行预鞣,然后采用3%铬鞣剂对其进行主鞣,所得蓝湿革收缩温度为95.8℃,撕裂强度为41.71 N/mm,粒面平细度良好,综合性能最优;鞣制废液中铬含量为58.0 mg/L、COD含量为6 670.0 mg/L,均低于常规铬鞣废液中的铬含量、COD含量。  相似文献   

7.
将经过聚丙烯酸钠(PAANa)预处理后的铬鞣废液直接循环回用于复鞣工序中,通过考察革中和废液中Cr2O3含量、Cr2O3吸收率等指标优化铬鞣废液预处理和复鞣工艺参数,并与常规铬复鞣工艺相对比。实验结果表明:经过PAANa预处理后的铬鞣废液回用于复鞣工序,Cr与皮胶原结合牢固,不易洗脱,所加工的皮张各项理化指标与常规皮革相比无明显差异。  相似文献   

8.
将宝斯卡铬鞣废液循环工艺技术应用在绵羊皮铬鞣过程中,在试验研究绵羊皮铬鞣操作废液循环利用工艺的基础上,系统检测并分析循环操作液的特征组分含量变化规律,同时也对相应蓝湿革的基本品质进行了综合评判。试验结果表明:操作循环液中Cr2O3、总有机碳、CODCr和氨氮等含量指标各自均有一定规律性的变化,并随循环次数的增加趋于累积平衡;操作液在循环过程中能够完全抑制六价铬的产生,所得绵羊蓝湿革品质稳定,其综合性能与常规铬鞣蓝湿革基本接近。研究结果揭示了绵羊皮铬鞣工序实施废液循环工艺技术的可行性与安全性,通过效益评估显示宝斯卡铬鞣废液循环技术在绵羊皮铬鞣工艺中推广应用具有显著的经济与环境效益。  相似文献   

9.
分别用普通铬粉和高吸收铬粉鞣制浸酸牛皮,对铬鞣剂的吸收情况和鞣革性能进行了对比研究。结果表明:高吸收铬粉鞣革后废液中Cr2O3含量(0.84g/L)明显低于普通铬粉鞣革后废液中Cr2O3含量(0.96g/L),Cr2O3吸收率提高了4.2%,并且高吸收铬粉鞣制后成革中的六价铬含量(3.4mg/kg)明显低于普通铬粉鞣革的六价铬含量(4.9mg/kg),高吸收铬粉鞣制有利于清洁化生产;高吸收铬粉鞣革与普通铬粉鞣革均耐煮沸;在Cr2O3用量相同的情况下,高吸收铬粉鞣革在蓝革增重率、物理机械性能及感官性能等方面,均优于普通铬粉鞣革。  相似文献   

10.
4高吸收有机助鞣剂应用工艺研究 有机助鞣剂与皮胶原的结合及其帮助铬的吸收的能力已经得到了证明。将其应用于具体的铬鞣工艺中,采用一系列对比实验,通过对蓝皮收缩温度、废液铬含量、面积得革率、皮革内铬的分布以及蓝皮物理机械性能等数据的测定,来说明助鞣剂预处理不浸酸铬鞣工艺与常规浸酸铬鞣工艺相比的优点,  相似文献   

11.
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.  相似文献   

12.
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.  相似文献   

13.
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.  相似文献   

14.
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.  相似文献   

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17.
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.  相似文献   

18.
<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  相似文献   

19.
《印刷工业》2014,(11):95-95
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%.  相似文献   

20.
《印刷工业》2014,(8):103-103
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  相似文献   

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