共查询到19条相似文献,搜索用时 125 毫秒
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肼及其衍生物在固体电极上的直接电化学行为研究 总被引:1,自引:1,他引:0
肼及其衍生物被广泛应用于医药,化工,军事,航天等领域,并被用作推进剂,水处理剂,农药,医药,燃料电池,光稳定剂以及化工生产助剂等诸多方面。因此对肼及其衍生物的研究和开发有着极其重要的理论意义和应用价值。本文研究了肼(Hydrzdine,DH),苯肼(Phenylhydrazine,PH),对硝基苯肼(p-Nitrophenykhzille,PNPH)和2,4-二硝基苯肼(2,4-DinitrophenyIhydrazine,DPH)在固体玻碳电极和铂电极上的不可逆电化学氧化行为, 相似文献
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二氧化碳(CO2)是一种来源丰富的C1资源,在温和条件下实现CO2的资源化利用是当前研究的热点之一。CO2环加成反应制备环状碳酸酯是CO2资源化利用的重要途径之一。环状碳酸酯是电池电解液的优良介质,可承受较恶劣的光、热及化学变化;同时也是聚氨酯、聚碳酸酯等精细化工中间体,广泛应用于医药、化工、纺织、印染等领域。非均相离子液体催化剂具有化学和热稳定性好、合成过程简单和可重复使用等优势。本文重点总结了近年来非均相离子液体催化剂在CO2和环氧化物环加成反应中的应用,并对非均相离子液体催化CO2环加成反应的发展进行展望。 相似文献
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具有"温度开关"特性的侧链结晶聚合物及其应用 总被引:1,自引:0,他引:1
具有“温度开关”特性的侧链结晶聚合物是一类新型的温度敏感智能材料,本文介绍了这类材料的结构特点、结构与温度敏感性的关系;综述了近年来国外对这类材料的渗透性能、粘合性能等及其在农业、包装、医药、化工等领域的应用研究进展. 相似文献
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Wenxin Zhang Min Xue Kenneth J. Shea Lili Qiu Zhibin Xu Jing Fan Dan Yan Zihui Meng 《中国化学快报》2021,32(1):587-590
Konjac tofu is a traditional Chinese food whose main ingredient is the water-soluble polysaccharide from konjac tubers-konjac glucomannan(KGM).Herein we report an interpenetrating double network polymeric film by crosslinking KGM and polyvinyl alcohol(PVA) with glutaraldehyde under acidic conditions.PVA was introduced into the hydrogel system as a hard skeleton,which not only maintained the biocompatibility of KGM,but also gave the hydrogel superior mechanical properties and solvent resistance.Implanting a colloidal array inside the above film,we obtained a new type of biomass based photonic crystal that is sensitive to a variety of physical and chemical stimulus,especially for methanol.This photonic crystal responds to metha nol and methanol vapo r,and has the ability to detect methanol in gasoline,which has a good application prospect. 相似文献
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To understand the effect of plasma treatment on the Konjac glucomannan film, the nitrogen plasma was injected into the film by ion beam injection machine in this study. The structures and properties of Konjac glucomannan film after plasma treatment were analyzed by Infrared spectroscopy, Raman spectrum, X-ray, ect. The result showed that nitrogen groups appeared in the KGM molecular chain and part of this chain fractured, and the number of hydrogen bonds increased after the treatment of plasma. The form of KGM molecule remained amorphous non-crystalline state, but the crystalline region was increased and became more ordered. The mechanical property of tensile strength and breaking elongation was improved, while the WVP was decreased. The nitrogen groups were grafted on the KGM molecular chain after plasma treatment, which led to the improvement of the properties of KGM film. 相似文献
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以魔芋葡甘聚糖(KGM)为原料,浓硫酸为催化剂,乙酸酐为改性剂,制备了KGM醋酸酯.研究了反应条件对KGM醋酸酯取代度(DS)的影响,KGM醋酸酯制备的最佳反应条件是乙醇∶水量比5∶5,反应时间2h,反应温度75℃,催化剂浓硫酸的浓度0.1mol/L,KGM与乙酸酐的量比5∶40(g/mL),取代度高达2.93,其分子量与KGM相比,则明显降低.运用傅立叶红外光谱仪(FTIR)、X射线衍射仪(XRD)、扫描电镜(SEM)、热重分析仪(TGA)、示差扫描量热仪(DSC)和旋转流变仪对KGM和高取代度KGM醋酸酯进行了表征.结果表明,KGM醋酸酯的羰基(CO)特征吸收峰较KGM明显增强,其表观形貌大部分为疏松絮状,KGM及其醋酸酯均为非晶态结构.与KGM相比,KGM醋酸酯的热稳定性下降,分解温度(Td)由KGM的261.10℃降低至KGM醋酸酯的204.56℃,KGM醋酸酯出现了明显的玻璃化转变,其玻璃化转变温度(Tg)为128.49℃.KGM醋酸酯是典型的黏弹性材料,其弹性比率占21.27%,其剪切黏度η对温度变化非常敏感,可通过温度的改变来调节KGM醋酸酯的加工流动性.KGM醋酸酯具有较好的热塑性. 相似文献
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Li Gui CHEN Zhi Lan LIU Ying Jun CHEN Ren Xi ZHUO 《中国化学快报》2005,16(12):1652-1654
Konjac glucomannan (KGM) was crosslinked with sodium tripolyphosphate (STPP) to synthesize hydrogels. The crosslinking reaction was confirmed by FT-IR. The results of degradation test show that the hydrogels retain the enzymatic degradation character of KGM and can be degraded for 74.45% in 5 days by cellulase E0240. 相似文献
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《结构化学》2016,(10)
In this paper,molecular dynamics simulation was applied to synthesize a layered structural color from Konjac glucomannan(KGM) and the effect of particle diameter and temperature were investigated. A series of methods such as high voltage electric field treatment,the transfer matrix method and the CIE standard colorimetric system were simulated to obtain the chromaticity coordinates and to analyze the color changes of KGM particles. The results revealed that as the particle diameter increases,the structural color of KGM particles deflects towards the yellow wavelength within the visible spectrum; and as the reaction temperature rises,the structural color deflects towards the blue and violet wavelengths within the visible spectrum. 相似文献
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《结构化学》2017,(9)
In order to effectively protect the activity of Epigallocatechin gallate(EGCG), we explored the protection mechanism of Konjac glucomannan(KGM) for EGCG by experiments and theory analyses. We synthesized KGM/EGCG nanofibers by using electrostatic spinning method. The microstructure of nanofibers was characterized by SEM, FTIR, TGA, XRD and Raman spectroscopic. The formation mechanism and the protection effects of KGM/EGCG nanofibers were also discussed. The results showed that the EGCG activity was protected due to the hydrogen bonds between-OH of EGCG and KGM, and EGCG was embedded in KGM nanofiber with bead style. The reducing force and DPPH scavenging ability data indicated that KGM/EGCG nanofibers have stronger antioxidant activity than the EGCG solution under the same condition. Hence, the mosaic topological structure of KGM can effectively extend the EGCG activity. 相似文献
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1 INTRODUCTION gel using KGM and borax at 60 ℃, which can be used as slow-released reagent of theophylline and Generally, the mixture of Konjac Glucomanan dibucaine. And Hogi Tsuneo utilized KGM and tetra- (KGM) and salts that could be hydrolyzed to form valent boric acid to prepare artificial crystal[1]. This multi-hydroxyl hydrates leads to the generation of kind of crystal has good light transmission property, gelatum. Among the familiar salts, such as borate, elasticity, intensi… 相似文献
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酶催化魔芋葡甘聚糖的可控降解 总被引:15,自引:0,他引:15
魔芋葡甘聚糖 (KGM)是一种来自植物的天然高分子 .它具有优异的可生物降解性和生物相容性 ,并具有许多独特的生理和药理功能 .本实验首先测定了 β 甘露糖酶在不同条件 (温度、pH值、介质 )下的活性 ,发现 β 甘露糖酶在 5 0℃左右 ,pH 9 4附近 ,乙醇含量低于 5 %的水介质中具有较高的活力 ;而在pH 7 0以下 ,或温度低于 3 0℃ ,或加入 2 0 %乙醇的条件下均基本上失活 .在此研究基础上 ,探讨了 β 甘露糖酶催化KGM降解反应的规律 ,通过调节反应条件制备了一系列分子量不同的降解样品 ,并确定了KGM的分子量与特性粘数之间的关系为 :[η]=5 0 6× 1 0 - 4M0 754w ,使得酶催化KGM的可控降解成为可能 ,从而为深入研究KGM及其衍生物的结构与性能 ,扩展其应用领域奠定了良好的理论和实验基础 相似文献