265 resultados para HOST MATERIAL
Resumo:
A total of 449 plateau pika (Ochotona curzoniae Hudgson) individuals were sampled with rattraps from 21 plots (size 1 ha) randomly scattered over the area of the species distribution at the altitude 3275-4807 in a.s.l. in the Qinghai-Tibetan Plateau (West China). Two main ectoparasite species Hypoderma satyrus Brauer and Ixodes crenulatus Neumann of plateau pika were surveyed, and the relations between host sex and parasitism were analyzed. The results were: (i) although not significantly, the infection rate of female young was close to zero and lower than that of male young (6%), while the infection rate of female sub-adults (19%) was contrarily - higher than that of male sub-adults (11%); adult females had significantly higher (41%) infection rate than that of males (18%) (P<0.001); (ii) the parasite infection rates for both males and females increased with increasing age, but female age-groups had obviously steeper slope. We suggested that the differences of body mass, growth rate and home range between males and females had mainly caused the sex-biased parasitism (SBP) of plateau pika at each age stage. Also, due to the higher increases of body mass and maybe as well as of the home range differences between consecutive age-groups, the parasite infections of females became more sensitive to the influences of age than that of males.
Resumo:
PASSIM卷接机组原控制系统采用电路板进行逻辑控制,抗干扰性能差,故障率高,造成生产效率降低、原材料消耗增大、维修工作繁重等。为此,设计了一套新型卷接机组电气控制系统。该系统采用PLC进行过程控制,以工控机为上位机完成人机通信,采用交流伺服驱动,并通过高速信号处理专用系统完成重量检测控制及烟支质量检测功能;利用PROFIBUS、CAN及MPI多种总线方式完成各单元间的通讯,实现信号和数据间的传递和共享。改进后的PASSIM机组运行稳定可靠,采样速度快,实时性强,且维修方便。机组的有效作业率由85%左右提高到90%以上,降低了卷烟纸和烟丝等原材料的消耗。
Resumo:
Honghuagou gold field, Inner Mongolia, is selected as the study area for the dissertation. The geological background for gold mineralization, geology of gold deposits, ore-controlling factors, physical and chemical conditions, material sources, genesis and ore-forming epoch for gold mineralization are studied in the dissertation. Especially, the Early Mesozoic tectonic and magmatic activities and their relationship with gold mineralization are studied with special efforts. Based on the study, the criteria for ore-prospecting are systemically summarized, target areas for ore-prospecting are circled and their gold reserves is estimated. Based on the first discovery of Early Mesozoic ductile zone which show the detachment features and the study on the emplacement of Early Mesozoic maficintermediate dyke swarms, the author present that the studied area was mainly in extensional uplift state during Early Mesozoic. The tectonic evolution can be divided into two stages. The extension was dominated by ductile metamorphose at early stage, whose geodynamics was related with the post orogenic extension after the collision between the Northern China Plate with Siberia Plate. The extension at late stage was featured by the intrusion of diorite and the emplacement of dyke swarms, whose geodynamics was related with mantle uplift. The gold deposits in the area are just the products of the tectonic and magmatic activities resulted from Early Mesozoic extension. The plagio-amphibolite from Archean metamorphic rocks is partially melted under the influence of underplating caused by mantle uplift, result in the formation of diorite magma. The gold in metamorphic rocks will also be melted into magma pond, and ascend into the upper parts of crust along with the intrusion of magma. The gold-bearing hydrothermal fluids is formed during magma differentiation, and caused the precipitation and concentration of gold in favorable geological conditions, result in the formation of gold deposits. The fracture caused by the emplacement of dyke swarms break a path for the ascending and movement of hydrothermal fluids, some of them become parts of ore-controlling and host structure. The gold is thought to be formed in Early Mesozoic, not in Yanshanian epoch.
Resumo:
A novel zirconium-based membrane material of BaCo0.4Fe0.4Zr0.2O3-6 with cubic perovskite structure was synthesized for the first time through a method of citric and EDTA acid combined complexes. The structural stability was characterized by XRD, O-2-TPD and H-2-TPR techniques respectively. The high oxygen permeation flux of 0.873 mL/cm(2) min at 950 degreesC was obtained under He/Air gradient. Meanwhile, the single activation energy for oxygen permeation and the long-term steady operation of 200 h at 800 degreesC were achieved.
Resumo:
Fibrosis caused by the host response to long-term transplanted microcapsules and the limitation of traditional L929 cell model for biocompatibility testing inspire the development of an assay of biocompatibility based on macrophage behavior. In this paper, the human monocytic cell line THP-1 was utilized for biocompatibility evaluation of microcapsule materials. The cell viability and secretion of nitric oxide (NO) and cytokines served as index of biocompatibility were assayed. It was found that the evaluated microcapsule materials had no effect on the stimulation of NO and cytokines secretion, which meant that these materials were biocompatible. Furthermore, it suggests the THP-1 cell a convenient in vitro experimental model that might be useful for long-term predictions of material biocompatibility.