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排序方式: 共有34条查询结果,搜索用时 15 毫秒
1.
符合药用质量要求的甲壳素精制工艺   总被引:3,自引:0,他引:3  
本文探讨了符合以下药用质量要求的甲壳素的精制工艺,甲壳素脱乙酰度在70-90%之间,钙的含量〈0.5%,总蛋含量在7-8%之间,灰分〈1%,酸不溶性灰分〈0.05%,无毒,为甲壳素在医药上的应用,提供了生产数据。  相似文献   
2.
Agar,agarose,and agaropectin were extracted from the red alga Ahnfeltia plicata,and their properties and structures were characterized.Agar was extracted by a comparatively low alkaline consumption of 1.2%.It exhibited a gel strength of 1 152.50±74.25 g/cm^2 and a sulfate content of 0.55%±0.08%.The yield of agar from A.plicata was 24.53%,which is higher than those of other agarophytes commonly used in China.Three kinds of the method were compared for the purification of agarose,and the physicochemical properties of agarose that was prepared under the optimal condition were identical to those of commercially available agarose.Furthermore,agaropectin was purified from A.plicata and characterized by GC,HPLC,UV-spectrum,and FI-IR to understand its composition and structure.It was the first time to comprehensively study the agar and its fractions from the red alga of A.plicata.This research provided an eco-friendly agar extraction method from A.plicata and revealed its potential application for the production of agar,agarose,and agaropectin.  相似文献   
3.
陈家超 《华南地震》1991,11(4):90-96
根据作者参加大会收集到的资料和考察体会,介绍了在会上交流的地震地质类成果,对某些前缘研究领域的新进展作了重点介绍。  相似文献   
4.
中国东南沿海地震带大震重复性和大震减震作用   总被引:2,自引:0,他引:2  
本文从物质分异的角度出发并利用现代小震活动资料,讨论了东南沿海地震带历史大震震源区及其附近,今后一段历史时期内是否有大震(M≥0)震源区大震重复性和大震减震作用问题。结果表明,这些历史震源区目前还处在减震阶段,今后一段时间只能以小震或中强地震的活动特点来显示这一弱化区。  相似文献   
5.
I. INTRODUCTIONResistance to flow in alluvial streams is one of the crucial problems in fluvial hydraulics. Despite that large amount of studies have been conducted for centuries, no perfectmethod describing and calculating the resistance to flow in alluvial streams is availablehll now. Investigation on bed forms and resistance properties of light--weight bed materials is even more scarce. USWES (1936) has conducted systematic experiments onlight--weight materials in a flume & m long an…  相似文献   
6.
An alkaline protease from Acetes chinensis was purified and characterized in this study. The steps of purification include ammonium sulfate precipitation, ion-exchange chromatography with Q-sepharose Fast Flow, gel filtration chromatography with S300 and the second ion-exchange chromatography with Q-sepharose Fast Flow. The protease was isolated and purified, which was present and active on protein substrates (azocasein and casein). The specific protease activity was 17.15 folds and the recovery was 4.67. The molecular weight of the protease was estimated at 23.2 kD by SDS-PAGE. With azocasein as the susbstrate, the optimal temperature was 55°C and the optimal pH value was 5.5. Ion Ca2+ could enhance the proteolytic activity of the protease, while Cu2+, EDTA and PMSF could inhibit its activity.  相似文献   
7.
甲壳胺油酸复合物是一种海洋生物活性多糖衍生物 ,以甲壳素油酸等作为原料 ,制备了甲壳素油酸复合物乳剂 ,并研究了其对大鼠和鹌鹑的减肥效果 ,结果表明 :将出生 2 5 d的大鼠 ,均喂以高脂肪高营养饲料。大鼠分为 4组 :对照组 ,高、中、低剂量组 ;并用出生 30 d的鹌鹑分 3组 (对照组 ,大、低剂量组 )。用上述动物试验了甲壳胺油酸复合物的减肥药效实验 ,实验结果表明 :甲壳胺油酸复合物具有明显的减肥作用。  相似文献   
8.
微晶甲壳质在乳白鱼肝油中的应用   总被引:2,自引:0,他引:2  
本文探讨了微晶甲壳质的乳化性能以及它在乳白鱼肝油中的应用。微晶甲壳质的独特性能如乳化性,持水性,稳定性等在乳白鱼肝油中都表现的比较明显。  相似文献   
9.
From material differentiation viewpoint, this paper discusses the crustal evolution in the South China Sea since Late Mesozoic times as well as the geophysical and tectonophysical features of the different types of Crust which exist there. On such basis, a seismic intensity regionalization is given.  相似文献   
10.
中国大地构造简述   总被引:9,自引:0,他引:9       下载免费PDF全文
我国的地质工作,自解放以来,在毛主席的革命路线指引下,获得迅速的发展,积累了丰富的资料。特别是自无产阶级文化大革命以来,以及在批林批孔运动的推动下,取得了更加重大的成就,全国地质情况已普遍作过查勘。这使构造地质工作者有条件在前人大量劳动成果的基础上,对中国大地构造从事进一步的总结和综合研究。  相似文献   
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