共查询到19条相似文献,搜索用时 109 毫秒
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在离子液沐中,采用钨酸为催化剂,用过氧化氢水溶液为氧化剂,一步催化氧化环戊烯合成戊二醛。催化体系经4次循环,催化活性未见明显降低,并进一步讨论了CPE与H2O2物料配比、反应温度、反应时间对戊二醛收率的影响,并确定了最佳合成工艺条件:n(C5H8):n(H2O2)=1:4,反应温度40℃,反应时间8hr。戊二醛总收率73%。 相似文献
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采用均匀设计法设计实验,以w(戊二醛)、m(PVA):m(SA)、m(CaCl2)和t(戊二醛与聚乙烯醇的反应时间)为考察因素,以含水率和拉断伸长率为考察指标,研究聚乙烯醇海藻酸钙复合膜的制备工艺条件。用红外光谱测定材料中交联反应的互溶性,用扫描电镜观察材料的组织形态。表明最佳制备工艺条件为:叫(戊二醛)-0.85%,m(PVA):m(SA)=7.5:1,侧(CaCl2)-2%,反应时间为1.5h。测试结果表明,制得的复合膜外观均一、光滑,柔韧有弹性,呈乳白色,含水质量百分率达到85.01%,拉断伸长率为494.80%。优选出的制备工艺条件可行性好。 相似文献
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采用混合酸(盐酸和柠檬酸)水解、戊二醛共聚交联等手段,对传统骨胶进行改性。以混合酸中柠檬酸的体积分数、水解温度、水解时间以及戊二醛用量作为试验因素,改性骨胶黏度和凝固点作为考核指标,采用单因素试验法优选出制备改性骨胶的最佳工艺条件。结果表明:当m(骨胶)=25 g、V(水)=25 mL时,改性骨胶的最佳工艺条件为25 mL混合酸中φ(柠檬酸)=0.06%、酸解温度65℃、酸解时间35 min和V(0.5%戊二醛)=1.5 mL;由最佳工艺条件制成的改性骨胶黏合剂,其凝固点为-2℃、黏度为1 850 mPa·s、剪切强度为1.87 MPa、开胶时间为1.5 h、适用期为90 d且具有良好的热稳定性能。 相似文献
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以壳聚糖和聚醚为原料、戊二醛为交联剂合成了壳聚糖-聚醚水凝胶。研究了壳聚糖-聚醚水凝胶溶胀机理,探讨了戊二醛浓度对该水凝胶的溶胀度、溶胀速率和溶胀动力学的影响。结果表明,戊二醛浓度不仅是影响水凝胶溶胀度的主要因素,随着戊二醛浓度的增大,壳聚糖-聚醚水凝胶的溶胀度逐渐减小,而且影响其溶胀动力学类型,当戊二醛浓度为0.107 mol·L-1,该水凝胶的溶胀过程属于Fickian类型,当戊二醛浓度为0.320、0.533 mol·L-1,其溶胀过程属于non-Fickian类型。 相似文献
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利用戊二醛对螺旋藻进行交联改性制备新型吸附剂吸附Cr6+研究。采用正交试验法对戊二醛改性螺旋藻吸附Cr6+的改性条件进行研究,结果显示:各因素对改性藻吸附Cr6+的影响由大到小的顺序为:戊二醛质量分数〉初始pH值〉改性时间〉藻类投加量,最佳试验条件为:戊二醛质量分数为6%,初始pH值为1,藻类投加量为0.5 g,改性时间为4 h。对原藻和改性后的藻吸附能力进行对比研究,结果显示:室温下对于100 mL Cr6+的质量浓度为80 mg/L的溶液,在藻的投加量为0.4 g、pH值为3时吸附效果最好。原藻和改性藻的Langmuir动力学方程的最大吸附量分别可达到7 889.5、14 424.5μg/g。 相似文献
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提出了液-液相转移反应萃取法制备戊二醛(GA)新工艺。此工艺过程是在相转移催化剂(PTC)与杂多酸(HPA)的参与下,用过氧化氢在有机相氧化环戊烯(CPE),生成的GA被萃取至水相。 相似文献
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银/二氧化硅复合载体固定木瓜蛋白酶的研究 总被引:2,自引:0,他引:2
以沉积了银纳米粒子的二氧化硅微球为载体,戊二醛为交联剂共价固定了木瓜蛋白酶。研究了戊二醛用量以及载体中银纳米粒子质量分数对酶负载率、相对活力和酶活回收率的影响,考察了温度和pH值对固定酶的影响。结果表明,戊二醛的适宜质量分数为5%;当载体的银负载量(质量分数)为0.68%时,固定木瓜蛋白酶活回收率最高,比使用未负载银载体提高了131%;固定酶的最适反应温度为75℃,与游离酶基本相同;最适pH值为7.5,与游离酶相比向碱性方向移动了1个单位。 相似文献
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To improve the covalent immobilization of penicillin acylase (PA), macromolecular crowding theory was applied to its immobilization. Influence of mass ratio of enzyme to the silica, as well as, activation time with glutaraldehyde on the activity of assembled PA, was studied. In the mesopores, the effect of fl-cyclodextrin (β-CD) on the immobilization of the enzyme was also investigated. It was remarkable that the coupled yield and relative activity reached 99.5% and 92.3%, respectively, when penicillin acylase assembled covalently in the mesopores. The results here indicate that mimicked macromolecule crowding could significantly ameliorate the performance of covalently immobilized PA. 相似文献
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The influence of glutaraldehyde blend on the properties of a commercially available resin in moist conditions was investigated. A UF resin with very low water resistance was blended with glutaraldehyde prior to the thermosetting step and the adhesive performance of the modified adhesive systems was studied. Experiments were performed on birch two-layer co-oriented plywood. It was shown that blending a commercial glue-mix as sold with glutaraldehyde can be an effective way to improve water resistance of the glue without introducing additional -NH2 moiety. It was also found that glutaraldehyde does not deteriorate properties of the glue in the dry state, while glue susceptibility to boiling water is markedly reduced. 相似文献
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Michele Miranda M Lúcia CP da Silva Heizir F de Castro 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2006,81(4):566-572
The aim of this work was to establish appropriate conditions for immobilising Candida rugosa lipase on a low‐cost inorganic matrix, hydrous niobium oxide, using a multivariate statistical approach. A 23 full factorial design was employed to determine the effects of support activation with glutaraldehyde (concentration 2.5–4.5%, pH 7–10) and lipase loading (200‐700 U g?1 matrix) on the hydrolytic and synthetic activities of the immobilised derivatives. From the results the following conditions were established: lipase loading of 450 U g?1 matrix and niobium oxide activation with glutaraldehyde at a concentration of 2.5% and pH 8. Under these conditions, high activity recovery (47.21%) and esterification yield (86.90%) were attained. The results also show that hydrous niobium oxide can be a valid alternative to replace high‐cost, commercially available inorganic matrices such as controlled pore silica. Copyright © 2006 Society of Chemical Industry 相似文献
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The influence of glutaraldehyde blend on the properties of a commercially available resin in moist conditions was investigated. A UF resin with very low water resistance was blended with glutaraldehyde prior to the thermosetting step and the adhesive performance of the modified adhesive systems was studied. Experiments were performed on birch two-layer co-oriented plywood. It was shown that blending a commercial glue-mix as sold with glutaraldehyde can be an effective way to improve water resistance of the glue without introducing additional –NH2 moiety. It was also found that glutaraldehyde does not deteriorate properties of the glue in the dry state, while glue susceptibility to boiling water is markedly reduced. 相似文献