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81.
为解决现有胡椒鲜果脱皮机脱皮不彻底导致含杂率高、脱皮力不当导致果核破碎及果核保护膜破损导致白胡椒色泽不理想等问题,在分析现有胡椒机械加工工艺的基础上,研制出螺旋式胡椒鲜果脱皮机。该机通过螺旋网面挤压胡椒鲜果,胡椒鲜果表皮在螺旋网面及容器内壁发生摩擦作用以完成脱皮。试验结果表明:螺旋式胡椒鲜果脱皮机的脱皮率达93%以上,且果核损伤率低于3%,符合设计要求。  相似文献   
82.
Inactivated vaccines of Avibacterium paragallinarum provide protection and reduce the economic losses caused by infectious coryza. However, inactivated bacterins provide protection only against the Page serovars included in the vaccine. In this study, we investigated the immunological properties of a functional recombinant haemagglutinin protein (rHagA) derived from a Taiwan isolate strain A9 as the immunogen for vaccination. The rHagA subunit vaccine protected 71% of immunized chickens against 10(10) colony-forming units (CFU) of viable A9. Vaccinated chickens which showed no clinical signs of coryza developed haemagglutination inhibition (HI) titers of 1:10 or greater. Haemagglutination (HA) of serovars A and C was not affected by the presence of rHagA specific antiserum. The HA of rHagA could only be induced against formaldehyde-fixed chicken red blood cells (FA-RBCs). These results suggested that HagA is a moderate immunogen and might not be a major haemagglutinin in vivo. However, HagA might be involved in haemagglutination when treated serovar C aggregates fixed RBCs in vitro.  相似文献   
83.
浮床种植草坪草对富营养化水体的净化作用研究   总被引:2,自引:0,他引:2  
采用浮床种植草坪草技术,研究了高羊茅Festuca arundinacea、匍匐翦股颖Agrostis stolonifera 2种草坪草对富营养化水体的净化能力.试验结果表明,2种草坪草对富营养化水体中的氮(N)、磷(P)、化学需氧量(CODcr)等具有明显的净化效果,尤其对总磷(TP)的净化能力最强,能有效改善富营养化水体的水质;2种草坪草之间,匍匐翦股颖对TP的去除效果显著高于高羊茅对TP的去除效果.研究结果显示浮床种植草坪草技术可能是一条有效的修复富营养化水域的新途径.  相似文献   
84.
Measurements of intestinal wall thicknesses from ultrasound imaging (US) are routinely used to support diagnoses of intestinal disorders in cats, however published studies describing observer agreement are currently lacking. The aim of this retrospective, observer agreement study was to quantify inter- and intraobserver repeatability and agreement in the measurement of intestinal wall layer thicknesses and the segmentation of transverse sections of small intestines in US images of 20 cats. Intestinal wall layer thickness measurements of the mucosa, submucosa, muscularis, serosa layer, and total thickness of these layers were performed on five cats with small cell epitheliotropic lymphoma, five with inflammatory bowel disease, and 10 with other conditions. Thickness measurements and the segmentation encompassing the serosa layer were obtained from five observers four times non-sequentially. The average standard deviation in thickness measurements (95% confidence interval) in the mucosa, submucosa, muscularis, serosa, and total thickness were 0.35 (0.07–0.95), 0.24 (0.07-0.52), 0.22 (0.06-0.49), 0.20 (0.05-0.49), and 0.57 (0.11-1.60) mm, respectively. The average intraclass correlation coefficients, which estimates the degree of consistency in thickness measurements and segmentation areas for each observer, ranged from 0.355 to 0.870 and 0.850 to 0.993, respectively. The interclass correlation coefficient, which estimates the degree of consistency when measuring a thickness or segmentation area over all observers ranged from 0.115 to 0.753, and 0.811 to 0.902, respectively. The overall average Dice Coefficient, which estimates the extent of overlap of the segmentations for all observers was 0.957 (0.933 to 0.972). Our results suggest segmentations of small intestines have a higher interobserver agreement than measurements of intestinal wall thicknesses.  相似文献   
85.
根据陕北农牧交错带的生态环境特点以及牧草生长发育过程对水热资源的要求和利用效率,运用迈阿密模型定量估算陕北农牧交错带七县区牧草自然生产力。并与牧草现实生产力进行比较。研究表明:陕北农牧交错带牧草现实生产力仅为自然生产力的30.80%。基本掌握了该区牧草生产力状况和特点,并据此提出了相应的开发战略和实施途径。  相似文献   
86.
穗肥施用时期对水稻籽粒中胚乳蛋白积累的影响   总被引:3,自引:1,他引:3  
以武香粳9号为材料研究了不同穗肥施氮时期对水稻籽粒蛋白质积累的影响.结果表明:穗肥的施用提高了籽粒发育过程中单位干重蛋白质含量,以在倒0.5叶施用氮素穗肥影响最大;随施肥时期的延迟,稻米粗蛋白和谷蛋白含量逐步上升,醇溶蛋白含量逐渐降低;倒2.5叶施氮减少了强、弱势粒中蛋白组分的分布和含量,倒0.5叶施氮与此相反;胚乳  相似文献   
87.
植物对磷饥饿的反应研究进展   总被引:4,自引:0,他引:4  
磷是构成生命的重要元素之一,也是土壤中有效性最低的一种营养元素。我国是世界上最大的小麦生产国。但是我国耕地中有59%的土壤缺磷。农作物的产量常受到缺磷的影响而受损。土壤缺磷并不是土壤中总磷量低,而是土壤中可供植物直接吸收利用的有效态磷含量低。植物在磷饥饿时会发生各种各样的变化,以尽最大可能满足自身对磷的需求。植物对缺磷的反应是一个复杂的网络过程。大约有100多个基因参与了植物对缺磷的反应。其中主要的有磷转运蛋白基因、核糖核酸酶基因、磷酸酶基因等。植物在吸收外界的磷的过程中磷转运蛋白发挥了重要作用。植物磷转运蛋白基因按照序列相似性可以划分为H+/Pi共转运家族(Pht1家族)和Na+/Pi共转运家族(Pht2家族)。按照吸收动力学的标准可以分为高亲和力磷转运蛋白和低亲和力磷转运蛋白两种。磷饥饿时植物对磷吸收能力的增强的原因之一是增加了磷转运蛋白分子的合成数目。目前尽管人们对植物吸收磷的理解已经有了长足的进步,但是在植物对磷的具体调控机制、磷的跨液泡膜运输等重要方面仍然没有明确的结果。  相似文献   
88.
An algorithm of fault section diagnosis based on topology identification for distribution networks is presented. By decomposing the topologic matrix which describing the distribution network into two parts,one part only contain the complex coupling factor ,and the other ignore the complex coupling factor. Using this method, the fault zones in distribution network can be identified and isolated efficiently, and the vertexes of the zones can also be identified automatically. This approach adapts to the changefully network structures.  相似文献   
89.
By analyzing the pressure distribution between gears and sealing blocks in compound gear pump with three idlers,the resultant hydraulic forces acting on seal blocks are obtained.The conclusion is the unbalanced resultant hydraulic forces are relatively small in magnitude.In the pump,the inner sealing edges are long and so it s Sealing effect is good,but the outer sealing effect is relatively poor because of its short sealing edges.The little unbalanced force pushes the sealing block to te pumping chamber,therefore it is advantageous to meliorating the pump's sealing effect,thereby to improving it's volumetric efficiency as well.  相似文献   
90.
In this paper,a new algorithm for solving large-scale finite element system is presented, which utilizes the architecture of parallel processing. Firstly, the structure is partitioned into sub-regions. Then multi-fronts are used to assemble and eliminate concurrently in every sub-region. Thus the condensed interface stiffness matrices and load vectors are obtained. By serially assembling and solving global equation to get interface displacements and backing to every sub-region, the inter-nodal displacements and element stresses can be solved. The results of computation show that it can not only increase the speed of computation,but also save the memory space of computer effectively. This algorithm is an effective method for solving large-scale structural finite element systems.  相似文献   
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