查询词典 chitosan

The factors affect on the degree of substitution of product, yield and apparent viscosity, such as the mol rates of EPTAC with -NH2, reaction temperature, reaction time and the content of water in system have been discussed in detail. FTIR spectrometer and UV spectrometer are used to characterize the structure of the derivative and it is proved that substitution reaction mainly occurs on the -N element .The particle size and morphology of chitosan and quantemary ammonium salt of chitosan are analysised by comparing photos of their scanning electron microscope. The degree of substitution of HACC is determined by acid -base conductometric titration. An error in current formula of DS has pointed out and a correct formula has presented.On the base of experience of above experiment, the reaction conditions of HACC were systematically investigated through orthogonal design, and then the best conditions are found. Water-solubility and dependence of pH are studied.

壳聚糖和环氧丙基三甲基氯化铵在异相条件下发生反应，通过单因素实验，制备了一系列不同性能的壳聚糖季铵盐，本文首次详细讨论了反应条件(反应摩尔比、反应时间、反应温度、水含量)对产率及产物性能的影响；用红外光谱和核磁共振对结构进行表征分析时，发现季铵盐阳离子基以N位上取代为主；通过电镜图片对壳聚糖和季铵盐衍生物外观形貌进行对比，采用酸碱电导滴定法测定产物的取代度，并对常用取代度公式做了修正。

This paper investigates the conditions of immobilization of chitosan adopting sodium alginate,poly and glutin as carriers,and farther uses the immobilized chitosan to adsorb the Cuand Crin water.

采用海藻酸钠、聚乙烯醇、明胶作为载体，对壳聚糖的固定化条件进行了研究，并以制成的固定化壳聚糖吸附水中Cu2+和Cr6+。

The other technical indexes are also accordance with document.conclusion:use methods such as taking off protein,calcium,colour,deacetylate and purification to abstract and preparing chitin and chitosan from xuyu's local lobster shell.the technology,equipments,operation are simple and have strong popularization.the chitin abstracted from xuyu's local lobster shell is rather high,it's a natural resources to prepare chitosan and is worth to exploit and utilize.

用本法从地产盱眙龙虾的虾壳中提取甲壳素和制备壳聚糖工艺设备简单，操作简易，具有较强的推广性；地产盱眙龙虾的虾壳含甲壳素较高，是一种制备壳聚糖不可多得的天然资源，值得开发利用。

Methods: 1. Rats in the study were divided into six groups: normal control group, hyperlipidemia group (fed with high-cholesterol diet), atherosclerosis group (vitamin D〓 intramuscular injection, endothelium denudate and fed with high-cholesterol diet with vitamin D〓), L-arginine group (besides treatment as atherosclerosis group, 2.25％ L-arginine was added in the drinking water), chitosan group (besides treatment as atherosclerosis group, 5％ chitosan was added in the diet), simvastatin group (besides treatment as atherosclerosis group, 0.03％ simvastatin was added in the diet). The study lasted 90 days.

1。实验大鼠分为6组：正常对照组、高脂血症组、动脉粥样硬化组(维生素D〓肌肉注射加动脉球囊损伤手术加含维生素D〓的高脂饲料饲养)、L-精氨酸组(动脉粥样硬化组基础上饮水中加入2.25％L-精氨酸)、几丁糖组(动脉粥样硬化组基础上饲料中加入5％几丁糖)、辛伐他汀组(动脉粥样硬化组基础上饲料中加入0.03％辛伐他汀)，90天后取标本检测。2。

This paper deals with different ways to depolymerize the chitosan into water soluble low molecular weight polymer.Molecular weight of water soluble low molecular weight chitosan was determinated by GFC.

探讨并比较了壳聚糖解聚成水溶性低聚物的不同途径，用GFC方法测定了水溶性低聚物的相对分子质量，证实选用NaNO2作解聚剂解聚效果良好。

BACKGROUND: Chitosan and its derivant are environmental-friend natural macromolecular materials, characterizing by great flocculation and adsorption capacities caused by electrophilic group including amino and hydroxyl groups, as well as its long-chain molecular structure. So chitosan is widely used as flocculants in domains of sewage disposal, food refining as well as Chinese medicine purification.

背景：壳聚糖及其衍生物是环境友好的天然高分子材料，其分子中丰富的带电基团如氨基、羟基以及长链分子结构赋予其优良的絮凝吸附能力，被作为絮凝剂广泛用于工业用水、食品精制以及中药液纯化等领域。

Optimized the preparation of chitosan hydrogel technological conditions, and the result indicated that: the hydrogel with best quality can be gotten, with the chitosan quantity 1 g, the formaldehydevolume 0.2 mL, the gelatination temperature 50℃.

通过试验优化制备壳聚糖水凝胶的工艺条件，试验结果表明：当壳聚糖量为1 g，甲醛体积为0.2 mL，凝胶化温度为50℃时，制备得到的水凝胶质量优良。

749Mg/ml and 0.778u/ml, respectively. 5. Study on the viscosity changes of reaction solution and analysis of enzymatic hydrolysis products by TLC, HPLC showed that ChiB was an endo-type cleavage enzyme. It decreased viscosity of reaction solution, hydrolyzed β-(1, 4) glucosidic bond of chitosan, acted on GlcN-GlcN, GlcN-GlcNAc and/or GlcNAc-GlcN glucosidic bond. It did not act on GlcNAc-GlcNAc glucosidic bond. Hydrolysis products of chitosan were composed of chitotriose, chitotetraose and chitopentose.

通过测定酶解液体系粘度和对酶解产物的TLC、HPLC分析，在国内首次深入地研究并报道了内切、外切壳聚糖酶的酶解作用模式，结果表明：酶ChiB是一种内切酶，以内切方式水解壳聚糖的β-（1，4）糖苷键，即作用于GlcN-GlcN、GlcN-GlcNAc和／或GlcNAc-GlcN糖苷键，不能作用于GlcNAc-GlcNAc糖苷键；酶解终产物以壳三糖、壳四糖、壳五糖为主。

It also widespread exists in the pericellular membrane of some fungus,insects,and algae,and in the cell walls of the advanced plant.The chitosan is the result of chitosan's dis-ethanoyl.

通过将甲壳素脱乙酰化可制得壳聚糖，壳聚糖是天然糖中唯一大量存在的碱性氨基多糖，其降解产物低分子量壳聚糖更是具有许多特殊的物理化学性质和生理功能。

Objective To investigate the possibility of self-assembling gene nanoparticles between the amphiphilic chitosan derivative and plasmid DNA, and study the interaction mechanism between N -methylene phosphonic chitosan and plasmid DNA, which might provide a new strategy for developing safe and efficient non-viral vectors.

目的 探讨双亲性壳聚糖衍生物与质粒DNA通过自组装的方式形成基因纳米粒子的可行性，考察载体与质粒DNA的相互作用机制，为开发安全高效的非病毒载体提供新的途径。

Cynanchum Lingtai apricot production in the average weight 65 grams, the brightly-colored fruit, juicy rich, sweet-sour taste, sweet from the nucleolus, when the late Qing Dynasty famous Shaanxi, Gansu provinces, the Qing imperial court Tongzhi tribute for years.

灵台生产的牛心杏平均单果重65克，果实色泽鲜艳，汁多味浓，甜酸适口，离核仁甜，清末时就驰名陕、甘两省，清同治年间曾为朝廷贡品。

Chenopodium album,Solanum nigrum, and Amaranthus retroflexus were very susceptible to the herbicides. Polygonum persicaria and Abutilon theophrasti were relatively less susceptible to the herbicides, and Lycopersicon esculentum was not susceptible to it. The relationship between reduction rates of weed biomass and PPM values of weed leaves 2,4, and 6 days after treatment was established.

供试的6种杂草对该混剂的敏感性存在显著差异：红心藜Chenopodium album、龙葵Solanum nigrum和反枝苋Amaranthus retroflexus对该混剂最敏感，ED90值分别为47.65、71.67和29.17g/hm2；春蓼Polygonum persicaria和苘麻Abutilon theophrasti敏感，ED90值分别为96.91、114.20g/hm2；而番茄不敏感。