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1.
以马尾松硫酸盐浆为原料,研究了复合绒毛化处理工艺中用碱量、H2O2用量、温度、浓碱处理时间对绒毛浆板及绒毛浆性能的影响。结果表明,复合绒毛化处理工艺的最佳条件为NaOH用量8%,H2O2用量1.8%,温度70℃,浓碱处理时间10 min。在此工艺条件下,马尾松硫酸盐浆经过复合绒毛化处理后,绒毛浆白度为76.1%,提高了25.9个百分点;绒毛浆板耐破指数为0.57 kPa·m2/g,下降了48.2%;紧度下降了11.8%;绒毛浆吸收时间为8.30 s,减少了47.5%;吸收性为9.14 g/g,干蓬松度为17.4 cm3/g,分别降低了8.32%、5.43%。复合绒毛化处理后,对绒毛浆进行一段补充漂白,白度可达到82.4%,绒毛浆各项性能均符合GB/T 21331—2008的要求。  相似文献   

2.
桉木硫酸盐浆OpZP漂白的研究   总被引:2,自引:0,他引:2  
对桉木硫酸盐浆OpZP漂白进行研究;确定了氧脱木素的条件为用碱量3%,温度100℃,时间60min,氧压0.6MPa,H2O2用量0.8%,浆浓12%;臭氧漂白条件为臭氧用量0.5%,浆浓45%;过氧化氢漂白条件H2O2用量2%,温度90℃,时间120min。桉木硫酸盐浆经OpZP漂白后白度可达到88%SBD以上。  相似文献   

3.
研究了芦苇硫酸盐浆H2O2强化氧脱木素及H2O2补充漂白。芦苇KP浆未漂浆卡伯值27.5,白度29.9%ISO,黏度1036mL/g,H2O2强化氧脱木素条件为:用碱量5%、氧压0.6MPa、H2O2用量2%、温度80℃、漂白时间60min,反应后纸浆卡伯值为4.1、白度63.0%ISO、黏度为864mL/g。随后再用H2O2进行补充漂白,所得纸浆卡伯值为3.2,白度81.0%ISO,黏度822mL/g。  相似文献   

4.
在实验室利用药液预浸和高温汽蒸预处理技术对三倍体毛白杨木片进行预处理,随后采用NaOH-AQ法制浆,得到低硬度化学浆.对该浆进行(Q/Op)QP全无氯(TCF)漂白,确定了(Q/Op)QP漂序较适宜的工艺条件为,H2O2强化氧脱木素段:浆浓10%,用碱量2.5%,H2O2用量3%,MgSO4用量0.5%,氧压0.6 MPa,温度100℃,时间60min;Q段:浆浓8%,DTPA用量0.3%,初始pH值4,温度70℃,时间60min;P段:浆浓10%,H2O2用量2%,MgSO4用量0.5%,Na2SiO3用量0.7%,温度90℃,用碱量1.5%,时间120 min.在适宜的条件下,三倍体毛白杨低硬度化学浆的白度可达82.0%ISO,黏度716mL/g,漂后浆得率91.78%.  相似文献   

5.
对亚铵法除髓玉米秆浆H2O2强化氧脱木素进行了研究,并通过正交实验得出H2O2强化氧脱木素的最佳工艺条件:浆浓9%,H2O2用量3%,用碱量4%,氧压0.6MPa,温度70℃,时间60min,MgSO4用量0.5%,Na2SiO3用量3%。在此条件下,漂白浆的白度可达72.5%,黏度为762mL/g。  相似文献   

6.
研究了马尾松低卡伯值硫酸盐浆高压高温H2O2漂白,探讨了漂白过程中压力、温度、时间、H2O2用量、Na2SiO3用量以及NaOH用量对漂后纸浆白度的影响.实验结果表明,在压力1.2MPa左右,温度125~130℃,时间1h左右,H2O2用量为4%~5%,Na2SiO3用量为3%,NaOH用量为1%,浆浓为10%的条件下,漂后纸浆白度可达80%ISO以上.  相似文献   

7.
研究了马尾松低卡伯值硫酸盐浆高压高温H2O2漂白,探讨了漂白过程中压力、温度、时间、H2O2用量、Na2SiO3用量以及NaOH用量对漂后纸浆白度的影响.实验结果表明,H2O2漂白在压力1.2MPa左右,温度125~130℃,时间1h左右,H2O2用量为4%~5%,Na2SiO3用量为3%,NaOH用量为1%,浆浓为10%的条件下,漂后纸浆白度可达80%ISO以上.  相似文献   

8.
研究了强化氧脱木素后的亚硫酸盐蔗渣浆过氧化氢漂白主要影响因素。结果表明:H2O2用量是最主要的影响因素,较适宜的漂白条件为:H2O2用量3.0%、漂白温度80℃、反应时间2h、碱量1.5%、浆浓10%。在此条件下,漂后浆卡伯值为8.9,纸浆黏度为753.2ml/g,白度为72.6%ISO。并提出进一步提高白度的方法。  相似文献   

9.
研究并开发了汽蒸与冷碱处理相结合(汽蒸-冷碱法)将漂白硫酸盐针叶木浆升级至溶解浆的技术。探讨了汽蒸处理过程中,汽蒸压力、维压时间、浆浓对汽蒸浆的黏度、抗碱性(R_(10))、得率以及废液p H值的影响;考察了冷碱处理过程中,碱浓、温度、处理时间对溶解浆的黏度、抗碱性(R_(10))、多戊糖含量及得率的影响。结果表明,汽蒸压力是影响汽蒸处理效果最重要的因素,维压时间次之,浆浓最小;碱浓是影响冷碱处理效果最重要的因素,温度次之,处理时间最小。汽蒸处理的适宜工艺条件为:浆浓40%,汽蒸压力0. 6 MPa,维压时间25 min;冷碱处理的适宜工艺条件为:浆浓20%,碱浓12. 5%,温度20~40℃,处理时间1 h。在此条件下制备得到的溶解浆各项性能为:黏度398 mL/g,抗碱性(R_(10)) 92. 2%,多戊糖含量3. 87%,白度86. 1%,达到了QB/T 4898—2015中针叶木溶解浆优等品的质量指标。  相似文献   

10.
两段高温高压过氧化氢漂白工艺的研究   总被引:3,自引:3,他引:0  
郭大亮  李新平 《中华纸业》2008,29(12):34-37
对硫酸盐竹浆两段高温高压H2O2漂白工艺进行了初步研究。结果表明,硫酸盐竹浆两段高温高压H2O2漂白工艺在控制两段反应条件分别为:压力1.2MPa和0.8MPa,温度100℃和120℃,时间40min和60min,H2O2用量1%和3%,浆浓10%,H2O2/NaOH用量比1.3,MgSO4用量0.5%,Na2SiO3用量3%时,可使漂后浆料粘度维持在780ml/g的情况下,白度值达到84%ISO。  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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