硫酸盐竹浆氧脱木质素和全无氯漂白的研究

通过比较不同条件下氧脱木质素后浆料的卡伯值、黏度、得率、白度和脱木质素选择性等指标,研究了硫酸盐竹浆卡伯值25.6氧脱木质素工艺参数,发现用碱量和温度是决定氧脱木质素效果的主要因素.最佳工艺条件为:用碱量3.5%,温度85℃,氧气压力0.6MPa,保温时间80min.两段氧脱木质素(中间不洗涤)可以提高木质素脱除率和选择性.研究还发现,在氧碱脱木质素过程中加入醌类混合物助剂(表示为Oq),可使浆料的黏度和氧脱木质素的选择性大大提高.采用OQ(PO)、(O1O2)Q(PO)、OQ(PO)1(PO)2和OqQ(PO) 4种短漂序都可使竹浆白度达到80%(ISO) 以上,且具有很好的白度稳定性.OQ(PO)、(O1O2)Q(PO)和OQ(PO)1(PO)2 3种漂序漂后浆纸页强度性能相近,OqQ(PO)漂后浆的抗张指数、撕裂指数和耐破指数明显高于其它3种漂序.     

桉树单板常温漂白工艺研究

采用过氧化氢作为主漂白剂,常温下对桉树单板进行漂白试验。以各组成药剂质量分数和漂白工艺为试验因素,以白度值为评价指标对漂白效果进行评价,并对比3种不同后处理方式对漂白效果的影响。结果表明,在常温下,桉树单板的最佳漂白工艺为浴比20∶1,氢氧化钠质量分数0.3%,双氧水质量分数5%,漂白时间10 h。3种干燥方式均可使漂白单板保持较高的白度值,生产中可任意选择或组合使用。     

硫酸盐竹浆全无氯漂白的研究

本文研究了硫酸盐毛竹浆的二甲基二氧环乙烷漂白，并提出了相应的全无氯漂白流程，研究结果表明，硫酸盐毛竹浆ＡＥＰ段漂白与传统的ＣＥＨ段漂白相比较，有较高的脱木素率和白度，再经过一段过氧化氢漂白，白度可达７８％（ＳＢＤ）．     

竹子溶解浆制备过程的浆料性能和结构表征1）

采用硫酸盐法（KP）-两段氧脱木素（OO）-聚木糖酶（X）及强化碱抽提的无元素氯漂白（D1ED2A）漂序制备竹溶解浆,并对各工段浆料进行性能和结构表征。结果表明：竹材经上述流程处理后,α-纤维素质量分数提高至95．19％,聚戊糖降至6．25％,ISO白度提高至86．8％,黏度下降至11．80 mPa· s,灰分降低至0．14％。扫描电镜分析得出,竹纤维表面出现了缝隙、沟槽、起皱等特征,微细纤维随着无元素氯漂白流程的进行暴露得更加清晰。 X-ray分析结果表明,浆料纤维素的晶型未发生转变,仍属纤维素Ⅰ型。在KP-OO-X-D1-E处理的过程中,纤维素结晶指数由59．77％提高至70．26％;随后进行D2-A处理,纤维素结晶指数降至67．77％。     

漂白粉液叶面消毒对家蚕原原种产卵性能的影响

以含不同质量分数有效氯的漂白粉溶液浸渍桑叶,进行全程桑叶消毒,饲育家蚕品种云7、云8原原种,调查漂白粉溶液对家蚕原原种产卵性能的影响。结果表明,漂白粉溶液中有效氯质量分数超过0．5％时,家蚕总产卵数和良卵数显著下降。     

山茶油简易精炼工艺的研究

针对衢洲山茶油精炼生产过程中出现的油皂不分、脱色效果不理想以及耐寒性差等主要技术问题,本论文在前人已有的研究基础上对山茶油精炼工艺中的碱炼、脱色、冬化等主要工艺进行了进一步的探讨,得到了一套更简单和更适用于生产的工艺流程。     

FAS漂白效能的影响因素

研究和讨论了一些主要过程参数的影响和某些金属离子对甲脒亚磺酸(FAS)在纸浆漂白中的影响,同时对FAS漂白过程中添加螯合剂的作用做了深入研究,结果表明螯合剂的加入能改善FAS的漂白能力.     

Dispersal of breeding, adult male Phocarctos hookeri: Implications for disease transmission, population management and species recovery

Dispersal impacts on a range of population parameters making it a key piece of information in species conservation. Despite its importance, dispersal is poorly characterized for many species: pinnipeds are no exception. Understanding dispersal patterns of the New Zealand sea lion Phocarctos hookeri is crucial in the conservation management of the species as its recovery to a non-threatened status hinges on range recolonisation. In this study, we examined the movements of breeding adult male New Zealand sea lions within and following the breeding season of the 2002/03 austral summer using a novel multi colony approach. Based on resightings of 202 individually identifiable adult males, we found (1) a previously unappreciated, high level of dispersal by adult territorial males between breeding colonies during the pupping period and (2) that breeding males disperse to the extremes of the species’ range at the end of female oestrous. Our findings are contrary to the current paradigm of otariid breeding behaviour, which is believed to consist of prolonged, uninterrupted male territoriality based on intense male-male competition and sustained fasting. Adult male dispersal between colonies and across the species range has important implications for adult males as vectors of disease in three recent epizootics, species management and species recovery via recolonisation as males are apparently remaining part of a localized, vulnerable breeding population.     

Oxidative cleavage of lignin aromatics during chlorine bleaching of kraft pulp

Methanol liberation and methoxyl loss during chlorine bleaching of softwood kraft pulp were quantitatively investigated to estimate the degree of structural modification of lignin aromatics. An increase in the chlorine multiple led to enhanced methoxyl loss from lignin. Our result, using pH-adjusted chlorine water (pH 5.7), by which chlorination under oxidation-favorable conditions was achieved, strongly supported the importance of the oxidation reaction by chlorine during delignification and lignin degradation. It was also suggested that methanol can be produced not only via catalytic hydrolysis by chlorine but via oxidative cleavage of the ether bond as well. The infrared spectrum of chlorolignins suggested that chlorine oxidation can open aromatic rings to muconic acid derivatives without cleaving ether bonding of the methoxyl group. No straight relation between the methoxyl content and the kappa number of chlorinated pulps was shown. The methoxyl content of bleached kraft pulps subjected to successive chlorination and alkali extraction showed a good relation with the kappa number. This means that almost all the portions of the oxidatively modified lignin structure were successfully removed during these treatments, and the aromatic structures of residual lignin in chlorinated and alkali-extracted pulps were thought to remain intact.Part of this paper was presented at the 46th Annual Meeting of the Japan Wood Research Society, Kumamoto, April 1996; the 10th International Symposium on Wood and Pulping Chemistry, Yokohama, June 1999; and the 67th Pulp and Paper Research Conference, Tokyo, June 2000