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1.
本研究对产自云南省西双版纳1.5年生的山黄麻(Trema orientalis)进行制浆造纸基础评价。结果表明,山黄麻的木质部纤维平均长度接近1.2 mm,综纤维素和酸不溶木素的含量分别为78%和21%。采用硫酸盐法制浆,在最高蒸煮温度160℃、NaOH用量21%、升温时间90 min、保温时间90 min的条件下,细浆得率为52.7%,再经氧脱木素-二氧化氯-过氧化氢加氧气强化的碱抽提(ODEop)短程漂白后,其纸浆得率99.6%,白度85.0%,漂白浆的抗张指数为79.0 N·m/g、耐破指数为5.15 kPa·m2/g、撕裂指数为5.81 mN·m2/g。  相似文献   

2.
文章主要探讨了蓝桉CTMP生产新闻纸的各种工艺参数,如药液配比、药液用量、浸渍时间、浸渍压力和磨浆条件等因素对浆料物理性能的影响。试验结果表明,当浆料打浆度被控制在63~73°SR时,浆张具有较好的强度性能,如裂断长为3660~4550m、撕裂指数为4.34~5.91mN·m2/g和较好的光学性能,如白度为54.6~59.5%ISO、不透明度为90.7~94.1%。用此浆料与漂白硫酸盐针叶木浆配抄,可获得优质新闻纸。  相似文献   

3.
尾巨桉KP-AQ制浆及漂白特性的研究   总被引:3,自引:0,他引:3  
对我国现有的尾巨桉的纤维形态、化学组成进行了分析,并对尾巨桉硫酸盐法制浆、漂白及其抄纸性能进行了研究。通过正交实验分析得出,尾巨桉KP-AQ制浆较佳的蒸煮工艺条件为:用碱量15%-17%,硫化度20%-22%;升温时间100-110m in,保温时间90-110m in,最高蒸煮温度165-170℃;蒽醌用量0.1%,液比1∶5.5。采用D1EpD2短程序漂白,尾巨桉KP-AQ浆的最终白度达到89.5%,黏度比漂前下降91.0 mL/g。打浆度在46.0°SR左右时,尾巨桉KP-AQ浆各项物理性能指标较好,抗张指数79.5N.m/g,撕裂指数21.90mN.m2/g,耐折度709次,紧度0.55g/cm3。  相似文献   

4.
柠檬桉、尾叶桉、柳桉制浆性能研究   总被引:5,自引:1,他引:5  
对柠檬桉、尾叶桉、柳桉3种速生桉木原料硫酸盐浆的制浆和漂白性能进行了研究,研究结果表明,3种桉木原料均具有优良的制浆和漂白性能。其较佳的蒸煮工艺条件为:用碱量(Na2O计):柠檬桉14%~16%,尾叶桉14%,柳桉12%,硫化度25%,最高蒸煮温度165~170℃,液比1:5,保温时间90~120min。采用DEpP短程序漂白,3种原料漂白浆的白度可达到85%ISO以上,且漂白浆的物理性能较好。  相似文献   

5.
对稻草酶预处理化机浆工艺进行研究,实验发现木聚糖酶较佳的用量为30 IU/g,化机浆的白度达到27.8%,裂断长为2.01 km,撕裂指数1.29 mN·m2/g;与低温磺化处理相比,NaOH处理更利于提高木聚糖酶的预处理效果且发现在化学处理前应用木聚糖酶处理意义较大,因为经过木聚糖酶预处理后便于药液进入原料内部与木素等成分作用。木聚糖酶、纤维素酶和果胶酶复配使用较佳的用量分别是20 IU/g浆、10 IU/g浆、15 IU/g浆,此时成浆纤维质量和成纸物理强度较好,耐破指数为1.18 kPa·m2/g,裂断长为2.23 km,环压指数为2.27 N·m/g,撕裂指数为4.49 mN·m2/g。  相似文献   

6.
探讨了蓝桉硫酸盐法制浆前提取半纤维素的可行性。用高温热水处理蓝桉木片以溶解其中的部分聚木糖。在选定的条件下,对预水解后木片进行硫酸盐法制浆。然后采用碱性氧脱木素、螫合处理及加压H2O2漂白的三段TCF漂白。漂后成浆卡伯值1.4、黏度641mL/g、白度86.4%。  相似文献   

7.
大花序桉KP法制浆性能研究   总被引:1,自引:0,他引:1  
张岳  姚春丽  吴宁 《中华纸业》2006,27(6):76-79
对我国现有的大花序桉进行纤维形态、化学组成和材质密度的分析,并对其硫酸盐法制浆及抄纸性能进行了研究。大花序桉硫酸盐法蒸煮优化条件为:用碱量19%,硫化度20%,蒽醌用量0.1%,升温时间100~110min,保温时间90~110min,最高蒸煮温度165℃,液比1∶5.5。研究结果表明,大花序桉是较优良的造纸原料。在打浆度为40~50°SR时纸张的各项物理性能比较好,分别为抗张指数39.2~45.2N·m/g,撕裂指数10.5~12.0mN·m2/g,耐折度331~429次,紧度0.428~0.442g/cm3。其撕裂指数优于其他桉木树种。  相似文献   

8.
桉木RDH硫酸盐浆和常规硫酸盐浆的ECF和TCF漂白   总被引:2,自引:0,他引:2  
对桉木RDH硫酸盐浆和常规硫酸盐浆的ECF和TCF漂白进行了研究,并与有元素氯漂白进行了对比.主要研究了用H2O2代替一段ClO2段以减少ClO2用量;采用H2O2强化碱抽提段(Ep)以实现短程序漂白;强化H2O2漂白(添加助剂的H2O2漂白)用以代替氧漂.结果表明,采用DEpP、Q(A+P1)P2和CEPH短程序漂白,均可将桉木RDH硫酸盐浆和常规硫酸盐浆漂至85%(ISO)以上的白度.两种漂白浆相比,RDH漂白浆具有相对较高的撕裂强度和较低的抗张强度.但两种漂白浆的强度均较高,抗张指数和撕裂指数均分别达到73N  相似文献   

9.
玉米秸穰改性后与麦草浆联合抄纸,返黄值稍有上升、不透明度有所下降,浆强度性能得到不同程度的改善。浆中秸穰含量为30%时,抗张指数和耐破指数分别为29.74N·m2/g和3.94kPa·m2/g,对比原浆分别增加了43.26%和47.01%。秸穰含量为10%时,撕裂指数达到最大值,为4.25mN·m2/g。同时,耐折度也有明显改善。此外,还对改性秸穰改善浆强度性能的机理做了简述。  相似文献   

10.
过氧乙酸用于短程序TCF漂白的初步研究   总被引:1,自引:0,他引:1  
研究了兰桉硫酸盐浆短程序TCF漂白中过氧乙酸(Pa)漂白的主要影响因素和过氧乙酸对后续H2O2、漂白的活化效果。对于经氧脱术素的兰桉硫酸盐浆,过氧乙酸是有效的脱木素剂和漂白剂。纸浆经Pa漂白后,能明显提高H2O2漂白效果。采用TCF二到三段漂白程序,可制备白度高于80%SBD,粘度大于800mL/g的兰桉TCF浆。  相似文献   

11.
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   

12.
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.  相似文献   

13.
The European Commission's, Quality of Life Research Programme, Key Action 1—Health, Food & Nutrition is mission-oriented and aims, amongst other things, at providing a healthy, safe and high-quality food supply leading to reinforced consumer confidence in the safety of European food. Its objectives also include the enhancing of the competitiveness of the European food supply. Key Action 1 is currently supporting a number of different types of European collaborative projects in the area of risk analysis. The objectives of these projects range from the development and validation of prevention strategies including the reduction of consumers risks; development and validation of new modelling approaches; harmonization of risk assessment principles, methodologies, and terminology; standardization of methods and systems used for the safety evaluation of transgenic food; providing of tools for the evaluation of human viral contamination of shellfish and quality control; new methodologies for assessing the potential of unintended effects of genetically modified (genetically modified) foods; development of a risk assessment model for Cryptosporidium parvum related to the food and water industries; to the development of a communication platform for genetically modified organism, producers, retailers, regulatory authorities and consumer groups to improve safety assessment procedures, risk management strategies and risk communication; development and validation of new methods for safety testing of transgenic food; evaluation of the safety and efficacy of iron supplementation in pregnant women; evaluation of the potential cancer-preventing activity of pro- and pre-biotic ('synbiotic') combinations in human volunteers. An overview of these projects is presented here.  相似文献   

14.
为研究低温带皮菜籽粕微粉的不同粒级部分的功能特性,以经低温脱脂的带皮菜籽粕为原料,经微粉碎后筛分成212~425μm、150~212μm和106~150μm的3个不同粒级的微粉样品,检测这些样品的吸水性、吸油性、乳化性和乳化稳定性、蛋白质体外消化率。结果表明:1 3个不同粒级的微粉样品之间的粗纤维含量存在显著差异,表明三者的结构组成成分有一定差异。23个微粉样品的乳化活性和乳化稳定性随粒度级别的减小而显著增加(P0.01)。33个微粉样品的蛋白质体外消化率随粒度级别的减小而显著增加(P0.01)。4不同粒级带皮菜籽粕微粉样品的吸水性与吸油性受其结构组成物质不同和粒度的双重影响,与粒度的相关性不明显。  相似文献   

15.
Microbiology of food taints   总被引:2,自引:0,他引:2  
Fresh and processed foods are often spoilt by the presence of undesirable flavours and odours caused by microbial action. The aim of this paper is to review the current knowledge of microbiologically induced taints that occur in a wide range of foodstuffs, including meats, poultry, fish, crustaceans, milk, dairy products, fruits, vegetables, cereals and cereal products. Examples have been chosen where the compounds responsible for the taint have been identified and sufficient data obtained to demonstrate the involvement of microorganisms. However, in some cases the full identity of the causative organism may not have been elucidated. The types of microorganisms covered by this review include bacteria, fungi, yeasts, actinomycetes and cyanobacteria. Although cyanobacteria do not in general infect foods, their presence in aqueous systems and water supplies can lead to off-flavours in aquatic organisms and processed foodstuffs. Several examples of each of these processes are discussed. Wherever possible, the likely biosynthetic pathway used by the microorganism to produce the offending compound in a foodstuff is indicated.  相似文献   

16.
Polymers intended for food contact use have been analysed for organic residues which could be attributed to a range of substances employed as polymerization aids (e.g. initiators and catalysts). A wide range of polymers was extracted with solvents and the extracts analysed by gas chromatography-mass spectrometry (GC-MS). The overwhelming majority of substances identified were not derived from aids to polymerization but were oligomers, additives and adventitious contaminants. However, a small number of substances were identified as initiator residues. These included tetramethylsuccinonitrile (TMSN) which was observed in two polymers and it derived from recombination of two azobisisobutyronitrile (AIBN) initiator radicals. Methyl benzoate, benzoic acid, biphenyl and phenyl benzoate were detected in one poly(methyl methacrylate) sample and in two polyvinylchlorides and they are thought to be derived from benzoyl peroxide initiator. TMSN was subsequently targeted for analysis of poly-(methyl methacrylate) plastics using proton nuclear magnetic resonance spectrometry (1  相似文献   

17.
Experiments were performed to characterize the kinetics of the permeation of different medium molecular weight model permeants: bisphenol A, warfarin and anthracene, from liquid paraffin, through a surrogate potential functional barrier (25 microns-thick orientated polypropylene--OPP) into the food simulants olive oil and 3% (w/v) acetic acid. The characterization of permeation kinetics generally observed the permeation models previously reported to explain the experimental permeation results obtained for a low molecular weight group of model permeants. In general, the model permeants exhibited behaviour consistent with their relative molecular weights with respect to (a) the time taken to attain steady-state permeation into the food simulant in which they were more soluble, (b) their subsequent steady-state permeation rates, and (c) their partition between liquid paraffin and the OPP membrane.  相似文献   

18.
This paper describes the first part of a project undertaken to develop mussel reference materials for Paralytic Shellfish Poisoning (PSP) toxins. Two interlaboratory studies were undertaken to investigate the performance of the analytical methodology for several PSP toxins, in particular saxitoxin (STX) and decarbamoyl-saxitoxin (dc-STX) in lyophilized mussels, and to set criteria for the acceptance of results to be applied during the second part of the project: the certification exercise. In the first study, 18 laboratories were asked to measure STX and dc-STX in rehydrated lyophilized mussel material and to identify as many other PSP toxins as possible with a method of their choice. In the second interlaboratory study, 15 laboratories were additionally asked to determine quantitatively STX and dc-STX in rehydrated lyophilized mussel and in a saxitoxin-enriched mussel material. The first study revealed that three out of four postcolumn derivatization methods and one pre-column derivatization method sufficed in principle to determine STX and dc-STX. Most participants (13 of 18) obtained acceptable calibration curves and recoveries. Saxitoxin was hardly detected in the rehydrated lyophilized mussels and results obtained for dc-STX yielded a CV of 58% at a mass fraction of 1.86 mg/kg. Most participants (14 out of 18) identified gonyautoxin-5 (GTX-5) in a hydrolysed extract provided. The first study led to provisional criteria for linearity, recovery and separation. The second study revealed that 6 out of 15 laboratories were able to meet these criteria. Results obtained for dc-STX yielded a CV of 19% at a mass fraction of 3.49mg/kg. Results obtained for STX in the saxitoxin-enriched material yielded a CV of 19% at a mass fraction of 0.34mg/kg. Saxitoxin could not be detected in the PSP-positive material. Hydrolysis was useful to confirm the identity of GTX5 and provided indicative information about C1 and C2 toxins in the PSP-positive material. The methods used in the second interlaboratory study showed sufficiently consistent analysis results to undertake a certification exercise to assign certified values for STX and dc-STX in lyophilized mussel.  相似文献   

19.
《造纸信息》2014,(8):80-80
On December 27t", 2013, the Ministry of Environmenta Protection announced that, in order to implement "The Environmental Protection Law of the People' s Republic of China", improve the working system in environmenta protection technologies, and promote technologica advancement in pollution prevention, the Ministry of Environmental Protection sponsored the formulation of three guiding technical documents including "Feasible Technology Guidelines for Pollution Prevention and Contro n Wood Pulping Process of the Paper Industry (Trial)"  相似文献   

20.
正On April 29th,2014,Intelli-Tissue EcoEc tissue machine supplied by PMP Group successfully put into operation at Hebei Xuesong Paper Co.,Ltd.,this is the first such kind of paper machine of PMP Group in China.  相似文献   

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