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151.
几种海洋动物的药用及其在临床上的应用 总被引:2,自引:0,他引:2
研究报告了牡蛎,贻贝,鲨鱼,海参,海胆的药效,对以这几种海洋动物为主要原料配制的药物的作用及用途作了简单论述。 相似文献
152.
应用自行开发的数值模拟软件 ,对胜利石油化工总厂 6 0× 10 4 t/a重油催化装置进行了分析和计算 ,得到了提升管内催化剂颗粒浓度、温度及产物沿提升管的分布情况。从模拟结果可以看出 ,在目前的操作情况下 ,该装置中柴油出现一定程度的过裂化 ,即轻质油收率最高点不在提升管出口。对产物分布曲线进行了分析 ,确定出终止剂的注入位置为 2 3.5m ,这为下一步的工业试验提供了依据 相似文献
153.
调距桨推进装置及其控制系统的建模与仿真研究 总被引:3,自引:0,他引:3
利用准稳态、循环平均值等建模方法,给出了包含MAN B&W 6S35MC柴油机、调距桨、螺距调节液压伺服装置、DGS8800e数字调速器、MAN B&W MC气动遥控系统以及Alphatronic 2000 PCS调距桨推进控制系统的实时仿真模型,开发了调距桨推进装置及其控制系统的仿真软件,给出了柴油机在不同负荷下的稳态和动态仿真曲线以及船舶在紧急倒航工况下调距桨推进装置的动态仿真结果.仿真计算与试验数据对比表明:模型能很好地预测调距桨推进装置及其控制系统在不同工况下的稳态和动态特性. 相似文献
154.
《Journal of Natural History》2012,46(5):641-662
Species of the marine nematode genus Pontonema have been found to dominate the macrobenthos under abnormally high conditions of particulate organic enrichment. Populations from organically enriched habitats in six localities (Kiel fjord, Germany; the Garroch Head sewage-sludge dump ground in the Firth of Clyde, Scotland; Cornelian Bay, N.E. England; the Tyne estuary, N.E. England; Sete, N.W. Mediterranean, France; Blanes Bay, N.W. Mediterranean, Spain) have been compared. Multivariate analyses of 16 morphometric characters in males, and 13 in females, shows that each population is significantly different morphologically from every other population. However, there is morphological overlap between the populations, and it is considered pragmatic to recognize three species in this group, based on a few stable morphological characters: P. vulgare (Bastian, 1865) from the Baltic, P. alaeospicula Bett and Moore 1988 from the UK sites, and P. mediterranea sp. nov. from the Mediterranean. P. mediterranea sp. nov. is described. The species were not found to have established sympatry in this study, unlike many other opportunistic taxa from organically enriched habitats, and the significance of this is discussed. 相似文献
155.
《Journal of Natural History》2012,46(8):1555-1574
A recent collection of anisakid nematodes from marine fishes from Japan and the North Pacific Ocean comprised a total of seven species of two genera; six of them (Raphidascaroides nipponensis Yamaguti, 1941, Hysterothylacium aduncum aduncum (Rudolphi, 1802), H. auctum (Rudolphi, 1802), H. cornutum (Stossich, 1904), H. marinum (Linnaeus, 1767) and H. physiculi sp. n.) parasitize fishes as adults, whereas one (Hysterothylacium sp.) occurred as larvae encapsulated in the host's abdominal cavity. Hysterothylacium physiculi sp. n. from the intestine of the gadiform fish Physiculus maximowiczi (Herzenstein) (family Moridae) from the western North Pacific (Kamaishi Bay, Honshu) is characterized mainly by shape of the lips, presence of well developed lateral alae starting some distance posterior to base of the lips, a short caecum, and markedly short (324-416mum) spicules. SEM study of R. nipponensis, type species of the genus, did not confirm the presence of dentigerous ridges on the lips. All species are briefly described and illustrated and some taxonomic problems are discussed. Several new host and geographical records are presented. 相似文献
156.
《Journal of Natural History》2012,46(8):999-1007
Three new species of Copidognathinae (Acari: Halacaridae) are described from the eastern coast of southern Africa (Mozambique; South Africa: Eastern Cape and KwaZulu-Natal). Copidognathus caloglossae sp. nov. and Acarothrix umgenica sp. nov. were collected in mangrove habitats, whereas Copidognathus xaixaiensis sp. nov. was collected on a rocky shore. Acarothrix umgenica represents the first record of the genus Acarothrix Bartsch, 1990 from the African continent. 相似文献
157.
R. Okamoto K. Hori K. Miyazawa K. Ito 《Cellular and molecular life sciences : CMLS》1990,46(9):975-977
Summary A new agglutinin has been isolated from the red algaGracilaria bursa-pastoris by affinity chromatography on a yeast mannan-Cellulofine column. This agglutinin was isolated as a monomeric glycoprotein with a relatively low molecular weight. It had an isoelectric point of 4.7 and contained large amounts of Gly, Asx and Glx. It agglutinated trypsin-treated rabbit erythrocytes at the low concentration of 30 ng/ml. The activity was inhibited only by glycoproteins bearing N-glycans. This agglutinin also showed mitogenic activity for mouse splenic lymphocytes. 相似文献
158.
159.
160.
考虑预应力分布的立管涡激振动特性分析 总被引:1,自引:0,他引:1
针对立管结构中存在着复杂预应力分布的现象,提出了考虑复杂预应力的立管涡激振动问题.基于梁结构理论,从应力-应变方程出发,建立了含复杂预应力的立管结构运动控制微分方程.对剪切流作用下典型顶张立管的涡激振动问题进行了数值计算,对比了复杂预应力对立管结构的自然频率、振型及典型节点振动特性的影响.计算结果表明,复杂预应力的存在对立管结构的动力特性有着重要的影响,特别是结构自然频率.文中所提出的方法可为复杂载荷作用下的立管结构动力特性问题的研究提供新思路. 相似文献