麦草乙醇浆臭氧漂白后过氧化氢补充漂白

麦草浆常规漂白工艺污染较大,故采用QZP短序TCF工艺漂白乙醇麦草浆。本文对麦草乙醇浆臭氧漂白后H2O2补充漂白进行了研究。高锰酸钾值18.2,白度26.4%ISO,黏度1135mL.g-1。经臭氧漂白后(臭氧用量为1.2%时),麦草乙醇浆高锰酸钾值4.0,白度增加到60%ISO,黏度为966mL.g-1。研究结果表明,在纸浆浓度12%,柠檬酸三钠用量1.0%情况下,H2O2补充漂白最佳条件为:H2O2用量3.0%,NaOH用量1.8%,漂白温度70℃,漂白时间120min,漂后浆的高锰酸钾值2.0,白度84%ISO,黏度908mL.g-1。     

三倍体毛白杨低硬度化学浆ECF漂白

利用氧脱木素和H2O2强化氧脱木素技术对三倍体毛白杨低硬度NaOHAQ浆进行了ECF漂白实验,经过ODED漂序漂白后,纸浆白度达到85.6%ISO,黏度701mL/g,而经过OPDQP漂序漂白后,纸浆白度达到88.3%ISO,黏度681mL/g。研究结果表明,这两种漂序可操作性强,是一种适合低硬度NaOHAQ浆的ECF漂白新工艺,且这两种纸浆手抄片的物理强度指标能够满足生产高档纸张的要求。     

过硼酸钠在欧美杨AS-AQ浆过氧化氢漂白中的应用

以欧美杨AS-AQ氧漂浆为原料,研究过硼酸钠(SPB)对过氧化氢(H2O2)漂白中减少漂剂用量起到的辅助作用。结果表明:对黏度要求不高时,SPB可以完全取代H2O2作为无氯漂剂,二者用量相同时,SPB最大可比H2O2漂白的白度高1.6%ISO,经一段漂3.0%的SPB可达到白度70.6%ISO。H2O2-SPB配合使用比单独使用H2O2白度高,最大可以上升2.0%ISO,且黏度比单独使用SPB的黏度高,即同时满足高白度和高黏度要求;2.0%H2O2-2.0%SPB漂白的白度可达73.6%ISO,比单独使用4.0%H2O2上升0.6%ISO,从而节约2.0%的H2O2。采用ODP-SPB多段漂,用2.0%H2O2即可以达到白度85.0%ISO,比对照样节约1.0%H2O2。经过碱性木聚糖酶处理后,OXDP-SPB漂序仅用1.0%H2O2白度达到85.4%ISO,比对照样节约2.0%H2O2。     

芦苇硫酸盐浆OpP漂白的研究

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。     

雷林106号桉木硫酸盐浆ECF漂白

研究了雷林106号桉木硫酸盐浆采用ODQP、OD1EoD2、OD1EopD2、OCuD1EopD2 4个漂白流程的无元素氯漂白,优化出了各漂白流程的最佳工艺条件.GIF仿酶预处理能有效改进漂白效果,提高纸浆白度.各漂白流程终漂纸浆白度分别为86.0%、84.2%、86.4%、89.1%,黏度分别为919 mL/g、863 mL/g、865 mL/g、833 mL/g.不同流程终漂纸浆物理性能都较理想.     

漆酶用于硫酸盐竹浆TCF漂白的研究

利用3种漆酶或漆酶/介体系统处理硫酸盐竹浆,并进行TCF漂白.结果显示,与传统的CEH漂白相比,硫酸盐竹浆进行包括漆酶/介体系统处理的OLQP白,在达到相近白度情况下,纸浆强度损失小;3种不同漆酶在HBT存在下的TCF漂白浆比CEH漂白浆黏度高43.3%～56.2%;从白腐菌HG产生的漆酶在HBT存在下处理硫酸盐竹浆,经OLQP漂白后,浆的白度可达80.7%ISO,黏度在800mL/g以上.在没有外加介体的情况下,该漆酶处理纸浆仍具有较好的脱木素效果,经OL0QP(L0,无外加介体)漂白后,纸浆白度可达76.7%ISO,比OQP漂后的浆白度提高了23.2%ISO.     

漆酶用于硫酸盐竹浆TCF漂白

利用两种漆酶或漆酶/介体系统处理硫酸盐竹浆,并进行TCF漂白。结果表明,硫酸盐竹浆进行漆酶/介体系统处理的OLQP漂白,漂白浆可以达到与传统的CEH漂白相近的白度,并且保持了更好的纸浆强度;从白腐菌HG产生的漆酶在HBT存在下处理硫酸盐竹浆,经OLQP漂白后,浆的白度可达80.7%ISO,黏度在800mL·g~(-1)以上。在没有外加介体的情况下,该漆酶处理纸浆仍具有较好的脱木素效果,经OL~0QPL~0,(无外加介体)漂白后,纸浆白度可达76.7%ISO,比OQP漂后浆的白度提高23.2%ISO。同时以苄甲基木素模型物藜芦醇为例,结合商品漆酶考察了白腐菌HG酶液催化氧化黎芦醇的反应动力学。     

硫酸盐竹浆高浓臭氧漂白工艺的研究

室温下,选取浆浓、臭氧浓度和反应时间3个变量,设计了三因素四水平的正交实验,研究硫酸盐竹浆高浓臭氧漂白各工艺参数的影响,并找出高浓臭氧漂白的最佳条件。实验结果表明:对于硫酸盐竹浆,在室温、浆浓35%~40%、臭氧浓度125 g·Nm-3、反应时间3 min的条件下进行高浓臭氧漂白,其白度69.4%ISO,黏度700.37 mL·g-1。     

高白度马尾松机械浆漂白工艺

马尾松是用于生产高得率浆的一种常用原料,但其机械浆漂白困难,纸浆白度较低,限制了在高档纸种中的使用。研究改进的马尾松CTMP浆的QP1P2Y漂白工艺,探讨了DTPA用量、H2O2用量及一二段分配比、连二亚硫酸钠用量对漂后纸浆白度的影响。研究发现,Q段DTPA最佳用量为0.4%,P1段H2O2用量2%,P2段H2O2用量4%,Y段Na2S2O4用量2.5%,漂后纸浆白度达到了78.1%ISO,并且纸浆的抗张指数和撕裂指数相比于未漂浆都有所提高,抗张指数为15.6N·m·g-1,撕裂指数为6.74mN·m2·g-1,能够满足配抄文化用纸的要求。     

二氧化硫脲漂白废纸脱墨浆的工艺优化

用二氧化硫脲(FAS)漂白混合废纸脱墨浆,探讨FAS用量、NaOH与FAS的碱比、浆浓、漂白温度和漂白时间对漂后纸浆白度的影响。结果表明,浆浓8%,FAS用量0.6%,温度80℃,时间60min时,NaOH与FAS的碱比0.5∶1最佳,浆的白度可达82.8%ISO,白度增值为5.4%ISO;延长漂白时间到65min,碱比调整为0.4:1或0.45:1,浆白度可达82.4%ISO,白度增值为5.0%ISO。     

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.     

Chlorohydrins of bisphenol A diglycidyl ether (BADGE) and of bisphenol F diglycidyl ether (BFDGE) in canned foods and ready-to-drink coffees from the Japanese market

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.     

European priorities for research to support legislation in the area of food contact materials and articles

A strong science base is required to underpin the planning and decision-making process involved in determining future European community legislation on materials and articles in contact with food. Significant progress has been made in the past 5 years in European funded work in this area, with many developments contributing to a much better understanding of the migration process, and better and simpler approaches to food control. In this paper this progress is reviewed against previously identified work-areas (identified in 1994) and conclusions are reached about future requirements for R&D to support legislation on food contact materials and articles over the next 5 or so years.     

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.     

Textural Properties of Cold-set Gels Induced from Heat-denatured Whey Protein Isolates

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.     

Influence des ions sur le pouvoir hydratant de l'ure e: e tude sur peau de porc ex vivo

This study deals with the influence of ions (NaCl and MgSO4) in a W/O emulsion containing 10% urea. Moisturization kinetics are assessed by corneometry on pig skin ex vivo. The formula's influence on urea penetration is measured by infrared spectrometry with an ATR device and the stripping method. Corneometry and spectroscopy were chosen to record simultaneously the hydratation levels and urea localization into superficial cell layers. Urea crystallization after evaporation of emulsions and aqueous solutions is described. Results show that urea does not hydrate nor penetrate when applied to the skin through an aqueous gel. In a W/O emulsion, sodium chloride increases the ability of urea to moisturize without improving penetration. In vitro urea crystallization is disturbed by sodium chloride or magnesium sulphate for solutions and emulsions. This stabilization by ions is correlated with good moisturization values. The stabilization of urea in the solute state provided by ions increases its water epidermal binding capacity without enhancing penetration.     

Occurrence of bisphenol-F-diglycidyl ether (BFDGE) in fish canned in oil

The levels of bisphenol-F-diglycidyl ether (BFDGE) were quantified as part of a European survey on the migration of residues of epoxy resins into oil from canned fish. The contents of BFDGE in cans, lids and fish collected from all 15 Member States of the European Union and Switzerland were analysed in 382 samples. Cans and lids were separately extracted with acetonitrile. The extraction from fish was carried out with hexane followed by re-extraction with acetonitrile. The analysis was performed by reverse phase HPL C with fluorescence detection. BFDGE could be detected in 12% of the fish, 24% of the cans and 18% of the lids. Only 3% of the fish contained BFDGE in concentrations considerably above 1mg/kg. In addition to the presented data, a comparison was made with the levels of BADGE (bisphenol-A-diglycidyl ether)analysed in the same products in the context of a previous study.     

Analysis on Economic Indicators from 62 Enterprises in Printing Machinery Industry in Q1 2014

Operation of printing machine industry was still unsatisfactory in the first quarter of 2014.Analysis on operation of printing machine industry.a.Market demand was not strong;sales of product undulated and declined.According to the statistics,the total industrial output value fell by 19.28% in the first quarter of 2014 than the average quarter value in 2013; industrial added value decreased by 4.16%; sales revenue dropped by 22.83%. h. Business operation of enterprises was in poor condition. c. R＆D of new products is an important transformation guarantee for enterprises. d. To take self explore new ways upgrading advantages,and explore new ways.