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1.
汪澜  林俊雄  袁近 《纺织学报》2005,26(2):82-84
 探索了天然黄色真丝绸和粗纤度真丝绸的高温高压环保型精练工艺。实验结果表明 :高温水精练是一种高效快速的精练工艺 ,在有效脱胶的基础上 ,有利于丝胶回收和环境保护。其中天然黄色真丝绸的最佳精练工艺为 120℃、30min、浴比 1∶100 ;粗纤度真丝绸的最佳精练工艺为 120℃、60min、浴比 1∶300。  相似文献   

2.
苎麻酶-化学联合脱胶工艺优化   总被引:1,自引:0,他引:1       下载免费PDF全文
为了减轻苎麻化学脱胶造成的环境污染,提高苎麻纤维可纺性能,采用酶化学联合脱胶法进行苎麻脱胶,分析酶脱胶过程中pH值、浴比、酶用量、金属离子、温度和时间对苎麻脱胶的影响,同时对浴比、酶用量、温度和时间进行4因素3水平的正交试验,采用优化后的工艺对苎麻进行酶脱胶、化学精练和漂洗。结果表明,苎麻在用KDN果胶酶第1步脱胶(浴比为1∶12,pH值为8.6,1 mmol/LMg2+,KDN果胶酶300 IU/g,45℃、4 h),TZ-888复合酶第2步脱胶(浴比为1∶18,pH值为4.0,1 mmol/L Ca2+,TZ-888复合酶500 IU/g,40℃,5 h)后残胶率为14.14%,进行化学精练和漂洗后最终残胶率为1.79%。  相似文献   

3.
将生物酶处理技术应用于棉杆皮纤维制取工艺,采用生物化学联合脱胶方法,研究了棉杆皮纤维的脱胶工艺。通过正交试验及模糊综合评价法,确定生物酶脱胶的最佳工艺为果胶酶质量分数12%(按织物质量计算),温度40℃,pH值4.4,时间30h,浴比1:30,化学脱胶处理的最佳工艺为NaOH质量浓度8g/L,H2O2质量浓度7g/L,温度90℃,时间45min,浴比1:50。  相似文献   

4.
大麻快速生物脱胶条件影响因素   总被引:2,自引:2,他引:0       下载免费PDF全文
 为提高大麻生物脱胶效率,对大麻快速生物脱胶工艺条件的影响因素进行研究。通过对选育的大麻快速脱胶菌株进行不同接种量、浴比、pH值、振荡转速和脱胶助剂的比较试验,研究大麻快速脱胶的工艺条件。结果表明,大麻快速生物脱胶的适宜工艺条件为:浴比1∶15,接种量20%,pH值6.5~7.5,振荡转速150 r/min,脱胶助剂为磷酸二氢铵,用量为大麻质量的0.05%。其中浴比和脱胶助剂对大麻生物脱胶效果的影响最大。  相似文献   

5.
《丝绸》2013,(10)
采用苹果酸对蚕丝进行脱胶,通过单因素实验,讨论了苹果酸质量浓度、反应温度、反应时间和浴比对蚕丝脱胶效果的影响,研究了脱胶后蚕丝的性能变化,得出了苹果酸的脱胶工艺条件。结果表明:最佳工艺为苹果酸质量浓度11 g/L,反应温度100℃,反应时间30 min,浴比1︰60。此条件下脱胶处理的蚕丝断裂强力损失与断裂伸长损失均较小,生丝中的丝胶基本上脱尽。蚕丝的红外光谱图研究结果表明,最佳脱胶工艺处理后蚕丝的主体结构不受影响。  相似文献   

6.
采用温水脱胶的方法,对乌拉草脱胶工艺进行研究。讨论了加酶量、浴比、初始pH和温度4个因素对乌拉草温水脱胶效果的影响,并测试了残胶率和酶活性的变化。以脱胶时间为考核指标,通过正交试验得到温水脱胶的工艺参数。试验结果表明:加酶量对脱胶效果影响最大,浴比对脱胶效果影响次之,酸性条件对沤草更为有利。正交试验得到的最佳工艺条件如下:温度55℃、加酶量10%、浴比1∶50、起始pH为5,尿素添加量2%。  相似文献   

7.
丝素蛋白的制备与脱盐研究   总被引:4,自引:0,他引:4  
田三德  解尚云  潘婕 《食品科技》2007,32(1):117-120
以蚕丝为原料,脱胶后,用Na2CO3溶液精炼两次,然后选用适宜浓度的CaCl2溶解丝素,并将所得溶液采用透析袋活水脱盐,经冷冻干燥后进行结果分析。实验所确定丝素蛋白制备的最佳工艺条件为脱胶精炼最佳浴比1∶50、最佳脱胶时间为30min、CaCl2溶解丝素时最适浓度为40%、浴比1∶10。  相似文献   

8.
罗布麻微生物脱胶工艺优化   总被引:8,自引:0,他引:8       下载免费PDF全文
 为了提高枯草芽胞杆菌对罗布麻的脱胶效率,根据菌种生长与酶催化反应所需温度的差异,将罗布麻生物脱胶过程分为2个阶段,并对脱胶工艺进行优化。试验结果表明:在磷酸氢二钾添加量为0.8%、浴比为1:25、枯草芽胞杆菌接种量为0.5%的条件下,在37℃脱胶18h,再升温至45℃脱胶0.5h,取得了良好的脱胶效果,罗布麻脱胶后的残胶率为10.84%,与未进行后阶段升温脱胶所得的残胶率相比降低了4.95%。  相似文献   

9.
对亚麻进行碱脱胶,以脱胶率、白度为指标,采用单因素实验法得出优化工艺:氢氧化钠8 g/L,Na2CO33 g/L,硅酸钠2.5 g/L,亚硫酸钠3 g/L,焦磷酸钠3 g/L,温度100℃,时间90 min,浴比1∶30;对脱胶后的亚麻进行过氧化氢漂白,以白度为指标,采用单因素实验法得出优化工艺:过氧化氢14 g/L,Na2CO31.5 g/L,硅酸钠3 g/L,亚硫酸钠0.5 g/L,温度100℃,时间100 min,浴比1∶30;在优化工艺下脱胶漂白的亚麻断裂强力为33.39 N,耐日晒色牢度为5级。  相似文献   

10.
采用生物脱胶工艺对乌拉草原茎进行脱胶。以残胶率为考察指标,分析果胶酶制剂用量、处理时间、温度、p H值4个因素对生物脱胶的影响,同时运用正交试验方法对乌拉草的果胶酶脱胶工艺进行优化。实验结果表明:在乌拉草生物脱胶过程中,酶制剂用量和酶处理时间对脱胶效果影响显著;当生物脱胶的工艺条件为酶制剂用量14%(owf)、脱胶温度45℃、时间16 h、p H值4.4、浴比1∶30时,残胶率为18.54%,为最优化条件。  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   

15.
16.
A 9% whey protein (WP) isolate solution at pH 7.0 was heat-denatured at 80°C for 30 min. Size-exclusion HPLC showed that native WP formed soluble aggregates after heat-treatment. Additions of CaCl2 (10–40 mM), NaCl (50–400 mM) or glucono-delta-lactone (GDL, 0.4–2.0%, w/v) or hydrolysis by a protease from Bacillus licheniformis caused gelation of the denatured solution at 45°C. Textural parameters, hardness, adhesiveness, and cohesiveness of the gels so formed changed markedly with concentration of added salts or pH by added GDL. Maximum gel hardness occurred at 200 mM NaCl or pH 4.7. Increasing CaCl2 concentration continuously increased gel hardness. Generally, GDL-induced gels were harder than salt-induced gels, and much harder than the protease-induced gel.  相似文献   

17.
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.  相似文献   

18.
Capillary electrophoresis (CE) and polarized light microscopy (PLM) were utilized in the detection of the adulteration of locust bean gum with guar gum. For CE analyses, standards of locust bean and guar gums were extracted with 30% CH3CN, removing the residual proteins from the gum matrix. A 8.75 mM NaH2PO4-20.6 mM Na2B4O7 buffer, pH 9, was used to separate these proteins and to identify marker proteins that were present in the guar gum. These markers did not co-migrate with components in the extracts of mechanically processed locust bean gum, and are used as indicators of adulteration. Using PLM with toluidine blue and iodine staining techniques, unadulterated locust bean gum samples were distinguished from mixed samples through the differential staining of components in locust bean versus guar and tara gums. These experiments in the use of CE and PLM provide orthogonal and complementary methods for the verification of 'true' positives and the elimination of 'false' positives.  相似文献   

19.
An investigation is described in which various polyfunctional compounds were applied to wool in attempts to stabilize the temporary improvements in wrinkle-recovery brought about by ‘annealing’. Several reactive systems involving formaldehyde were found to produce the desired permanently improved wrinkle-recovery.  相似文献   

20.
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