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1.
壳聚糖铜 /锌配合物复配的防白腐效果分析   总被引:1,自引:0,他引:1  
壳聚糖金属配合物(CMC)是一种环境友好的木材保护剂,根据壳聚糖锌配合物(CZC)对褐腐菌(Poria placenta)的防腐效果优良,而壳聚糖铜配合物(CCC)对白腐菌(Coriolous versicolor)的防腐效果好的特点,本研究将CZC与CCC复配为壳聚糖金属配合物混合液MCMC,进行防白腐试验.结果显示复配后的MCMC,提高了其对木材白腐菌的耐腐能力,防白腐效果与CCA相近.  相似文献   

2.
天然药物有效成分的金属配合物研究进展   总被引:1,自引:1,他引:0  
综述了国内外学者对天然药物有效成分的金属配合物的研究概况.研究对象包括黄酮类化合物、生物碱、香豆素和醌类化合物,性质研究主要在抗菌、抗病毒及抗癌方面以及光学和磁学活性方面.这些研究为开发抗癌新药以及研究天然药物金属配合物结构的多样性和性质的多重性方面提供一些有价值的结论.  相似文献   

3.
竹浆GIF仿酶漂白木质素降解产物气相色谱-质谱解析   总被引:1,自引:0,他引:1  
利用气相色谱-质谱联用(GC-MS)方法对GIF仿酶漂白中的木质素降解产物进行了分析,进一步探讨这种仿酶系统对木质素的降解机制.结果显示GIF仿酶处理使竹浆残余木质素进一步氧化降解,降解的主要方式有脱甲基作用、醌型结构的产生和开环、烷基-芳基醚键的开裂、侧链碳-碳连接的氧化断裂等.GC-MS检测所得的降解产物中,含羰基的化合物较多,这是GIF仿酶系统催化氧化的结果.一些醌式结构、共轭羰基和酚类的脱除,也使纸浆因发色基团减少而白度提高.此外,检测出一些糖类降解产物,说明GIF仿酶系统对纸浆碳水化合物有一定的降解作用.  相似文献   

4.
采用氨基腰果酚作为配体与氯化铜制得了氨基腰果酚铜(Ⅱ)配合物(AC-Cu^2 )。通过红外光谱、光电子能谱和热重分析等研究了AC-Cu^2 的结构特征,并研究了该配合物催化引发单体聚合的特性。结果表明,氨基腰果酚分子中-OH、-NH-等功能基与Cu^2 发生了配位作用,形成配位数不饱和的配合物;该配合物在亚硫酸钠水体系中能催化引发单体甲基丙烯酸甲酯(MMA)、甲基丙烯酸丁酯(BMA),于室温、无搅拌、不除氧条件下聚合。  相似文献   

5.
脱木质素的催化效应   总被引:4,自引:0,他引:4  
对4种杂多酸盐——Na4[PMo11VO40]、Na5[PMo10V2O40]、Na7[P2Mo17VO62]和Na2[P2Mo16V2O62]催化的硫酸盐浆酸性H2O2脱木质素的效果进行了考察,并对Na5[PMo10V2O40]催化H2O2脱木质素的温度效应进行了探讨。结果表明,4种杂多酸盐对硫酸盐浆H2O2脱木质素均有较强的催化活性,但它们也加速了碳水化合物的降解。卡伯值降低率和粘度降低率随杂多阴离子负电荷数的增加而降低。Na5[PMo10V2O40]催化的H2O2脱木质素过程似乎呈现出“异常”的温度响应,在60℃左右卡伯值降低率最大。随着反应温度的升高,纸浆的粘度降低率增加。对于杂多酸盐Na5[PMo10V2O40]催化的H2O2脱木质素工艺,温度定为60℃最佳。  相似文献   

6.
合成了脱氢枞胺(5-硝基)水杨醛Schiff碱及其Cu2 、Zn2 、Co2 和Ni2 配合物,用IR、1HNMR,UV-vis,摩尔电导及单晶X射线衍射对其进行结构表征.Cu(L)2形成经典的N2O2配体配合物,属于单斜晶系,C2空间群,晶胞参数为:a=3.6996nm,b=1.0835nm,c=1.2856nm,α=90°,β=103.36°,γ=90°.研究了溶剂的极性对配体和配合物紫外光谱变化的影响,当改变溶剂时,配体能发生分子内质子转移,从醇式结构变成酮式结构.金属配合物能溶于有机溶剂,摩尔电导率数据表明它们在二甲基甲酰胺、氯仿和甲苯中是非电解质,容易发生溶致变色性能.对配体及配合物进行了抑制大肠杆菌、金黄色葡萄球菌及枯草芽苞杆菌的生物活性测定,配体及配合物都表现出一定的生物活性,其中Cu配合物的活性最强,说明配合物的生物活性与金属有关.  相似文献   

7.
深入研究β-O-4型木质素模型化合物——愈创木基丙三醇-β-愈创木基醚的合成新路线,并利用红外光谱和核磁共振谱对其化学结构进行了分析。采用由Cu^2 吡啶/过氧化氢组成的GIF(GIF-sur-YVETTE)型仿酶体系对这一木质素模型物进行了仿酶降解的研究,并采用GC-MS、^13C NMR等方法分析了该β-O-4型木质素模型化合物在降解过程中的结构变化,在此基础上对这种仿酶降解的机理进行了探讨。研究结果表明:利用溴化铜对4-乙酰基愈创木酚进行溴化后很容易得到4-(α-溴化乙酰基)-愈创木酚中间体,从而提高了合成愈创木基丙三醇-β-愈创木基醚的效率。GIF仿酶降解体系对β-O-4型木质素模型物有较强的碎解能力,降解后产生一系列含羟基、醛基和羧基的芳香族低分子化合物,根据反应产物的结构可以说明β-O-4型木质素模型化合物的主要降解途径为:β-O-4醚键断裂、Cα-Cβ键断裂、Cβ-Cγ键断裂。本研究为该仿酶降解体系在无污染漂白工业上的应用提供理论依据。  相似文献   

8.
以4年生新伐毛竹为试材,以白腐菌彩绒革盖菌为试菌,对壳聚糖铜配合物(CCC)、壳聚糖锌配合物(CZC)及相应的金属盐(氯化锌)和铜铬硼(CCB)处理材的抗流失性和耐腐性能进行试验.结果表明: 壳聚糖金属配合物在竹材中固着率略高于CCB,明显高于相应的金属盐,具有较强的抗流失性能;CCC处理的竹材对彩绒革盖菌的耐腐性能高于CCB处理材, 当CCC处理材中金属离子保持量达到6.35 kg·m-3时,腐朽后质量损失为0;CZC处理毛竹试材的耐腐效果和CCC效果相当,明显高于氯化锌处理材,当防腐剂中金属离子保持量高于2.41 kg·m-3时,CZC处理的竹材都达到最耐腐等级,且随着防腐剂中金属离子保持量的提高,处理材的质量损失率接近于0.  相似文献   

9.
以H2O2为氧源,研究了歧化松香胺Schiff碱-铜配合物催化苯乙烯的氧化反应,探讨了溶剂种类、催化荆用量、氧化剂用量、反应温度及反应时间对催化氧化反应的影响。结果表明,催化氧化反应的较佳条件是:以1,4-二氧杂环己烷为溶剂,苯乙烯5.000g,催化剂Schiff碱-铜配合物用量为苯乙烯质量的0.5%,质量分数为30%的H20:15mL,80℃反应6h。苯乙烯转化率为93.3%,主产物苯甲醛的收率和选择性分别为66.8%和71.7%。  相似文献   

10.
总结了近年有机电致磷光材料的发展概况,分析了电致磷光二极管材料发光机理及有机配体结构对金属配合物的稳定性、发光效率、发射波长的影响,论述了金属有机配合物电致磷光材料的发展前景,并提出今后磷光材料的发展方向。  相似文献   

11.
研究了酶处理对相思木EMCC(延伸改良连续蒸煮)硫酸盐浆(KP浆)氧脱木质素效果的影响。结果表明,由白腐菌直接合成的漆酶/木聚糖酶体系(LXS)预处理相思木EMCC硫酸盐浆的的适宜酶用量为7 IU/g;LXS预处理后浆料氧脱木质素的适宜反应时间、最高反应温度及用碱量分别为60 min、100℃和2.5%;利用LXS进行氧脱木质素后处理的适宜反应时间及酶用量分别为2 h和5 IU/g。SEM观察到经过酶处理后纤维表面及横切面出现大量的裂隙及孔隙,其中以酶后处理最为明显,为后续漂白中化学药品的渗透和漂白降解产物的溶出创造条件。  相似文献   

12.
经乙二胺预处理后大豆秸秆先溶解于8%LiCl/DMSO木质纤维全溶体系,然后于乙醇中凝胶化制备多孔吸液木质纤维凝胶。研究发现:木质纤维原料脱木质素程度会影响凝胶的多孔结构、热稳定性及溶胀性能。随着脱木质素程度加强,木质纤维原料中纤维素、半纤维素和木质素之间解离程度加强,凝胶热稳定性提高,残炭量减少,可形成小孔径、高比表面积的致密多孔网络结构并影响其溶胀性能。当大豆秸秆经2 h脱木质素处理时,该秸秆原料所制备的凝胶热分解温度、残炭量、比表面积和平均孔径分别为230℃、15%、64.29 m~2/g和17.813 nm,在15℃下平衡溶胀率为2 126.79%,与未脱木质素的大豆秸秆制备的凝胶相比,热分解温度提高了30℃,残炭量降低了47.7%,比表面积增加11.02 m~2/g,平均孔径减小了2.468 nm,而平衡溶胀率降低了16.6%。  相似文献   

13.
在大分多相催化反应中,由于反应物分子较大,使反应分子不能进入固相催化剂的微孔中与涵性组分接触,因而分布于载体微孔中的活性组分对于大分子的催化反应是无效的。本文报道了用“浸渍胶体”法制备出松香大分子改性用Pb/c催化剂,该催化剂活性组分较集中分布于活性炭表面及大孔周围。与传统浸渍法制备的Pd/c催化剂在松香歧化反应中比较,新方法制备的催化剂显示出更好的活性,克服了松香大分子因“孔效 ”造成传统浸渍法制备的Pd/c催化剂中小孔周围的活性组分不能效使用的缺点。  相似文献   

14.
Due to the complexity of delignification, it is still not accurate enough to describe the whole chlorine dioxide delignification system with mechanistic models such as kinetic studies. The simple aim of predicting and optimizing the process requires the use of economical empirical models, few of which are in the literature. In this study, principal component analysis was used to classify various bleaching response variables, including end pH, kappa number, viscosity, and optical properties such as brightness, into different categories. Statistical methods, including factorial design, multiple regression, and response surface methodology, were then used successfully to screen the importance of bleaching factors and their interactions. Models to control, predicate, and optimize the bleaching responses were established. In most cases, the results of empirical modeling coincided well with those from conventional research methods, but the empirical methodology was more economic or less laborious. The empirical models are robust enough to predicate and optimize the bleaching responses to chlorine dioxide delignification of oxygen-delignified hardwood kraft pulp.  相似文献   

15.
The aim of this study was to investigate the effects of plum gum liquor and sodium perborate addition to oxygen delignification process on spruce kraft pulp properties. Yields and viscosity of pulp were protected against oxidative attack, when kappa number of pulp was not changed by adding plum gum to oxygen delignification process. Delignification ratio improved by 7.4% without any viscosity loss by adding only 0.25% sodium perborate as active oxygen with plum gum liquor to the oxygen delignification process. It was found that crystallinity of pulp was improved by adding plum gum and sodium perborate to oxygen delignification. It was also determined that sodium perborate had an affirmative effect on delignification ratio, when plum gum affected pulp viscosity positively.  相似文献   

16.
Summary Delignification studies on 0.5 m sections of Douglas-fir earlywood tracheids pulped by soda, soda-anthraquinone (soda/AQ) and kraft pulping processes were performed by determining bromine concentrations in various morphological regions with SEM-EDXA technique. Soda/AQ pulping was much more selective in removing lignin from the middle lamella regions than either soda or kraft pulping. However, up to 50% delignification, more lignin was removed from the secondary wall by soda or kraft, compared to soda/AQ pulping. The kinetics of lignin removal in the various morphological regions were established. Addition of AQ and sodium sulfide resulted in an earlier transition from a slow initial to a rapid bulk delignification, particularly in the middle lamella, and in an enhanced bulk delignification in the secondary wall. Anthraquinone was also found to promote residual delignification in the secondary wall, where sodium sulfide was not effective. The opposite was observed for the bulk delignification in the middle lamella, where only sodium sulfide addition improved the rate significantly. The great differences observed in the bulk delignification rates between middle lamella and secondary wall in soda pulping as well as their response to additives suggest structural differences between middle lamella and secondary wall lignins.Paper No. 6712 in the Journal Series of the North Carolina Agricultural Research Service, Raleigh, North Carolina. The paper, an excerpt from the Ph. D. dissertation of Shiro Saka, was selected for the second place Wood Award for 1980 cosponsored by Forest Products Research Society and the Kirby Forest Industries, Inc., Houston, Texas, and presented at the American Chemical Society Annual Meeting, Las Vegas, Nevada, August, 1980  相似文献   

17.
A marine fungus,Phlebia sp. MG-60, and three white-rot fungi were incubated with whole sugarcane bagasse (WSB). The residual lignin content and holocellulose content in the decayed WSB were determined, and based on their content delignification selection factors of the fungi were calculated. More than 50% of lignin in the WSB was degraded byPhlebia sp. MG-60, and less than 10% of the holocellulose was lost. The WSB was fractioned by sieving to separate long-fiber bagasse, shortfiber bagasse, and bagasse pith. WhenPhlebia sp. MG-60 was incubated with the three fractions, more efficient delignification activity on the bagasse pith was observed. As the most efficient utilization of bagasse, we predict that bagasse fiber might be employed as the raw material in the pulp and paper industry after biopulping withPhlebia sp. MG-60 and bagasse pith, or WSB might be used to produce animal feed after fermentation with the strain.  相似文献   

18.
提出了非木材木质纤维生物质碱性亚硫酸盐制浆(ASP)生物炼制的理念,研究了总用碱量、亚硫酸化度、温度和时间对麦草碱性亚硫酸盐法蒸煮深度脱木质素特性和木质素磺化的影响。结果表明:麦草ASP法具有高的深度脱木质素选择性;深度脱木质素延伸与木质素磺化度提高具有一致性;总用碱量、亚硫酸化度、最高温度和保温时间对深度脱木质素选择性和木质素磺化度都有重要的影响;在总碱用量18.0%,亚硫酸化度85.0%,液比值3.5,最高温度168℃,保温150 min的条件下,可制得卡伯值8.8,得率56.8%,黏度为33.3 mPa.s的优良纸浆,此时黑液中磺化木质素磺酸基含量达2.16 mmol/g(以固形物计)。从深度脱木质素选择性、木质素磺化和纸浆基本特性考虑,麦草ASP法具有制浆生物炼制的前景。  相似文献   

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