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1.
为提高车辆抗侧翻能力减小其侧翻的危险性,建立了11自由度整车侧翻模型。根据各系统侧翻控制权重及有效作用范围,提出一种基于转向、悬架和制动的多系统侧翻控制策略并设计了相关控制器。对系统单独控制及综合控制进行了仿真对比分析。结果表明,综合控制策略在提高车辆抗侧翻能力的同时也很好的改善了车辆侧向稳定性。  相似文献   

2.
Summary A method has been developed for transmitting infection of mammalian malaria by inoculation of exoerythrocytic schizontz. The possibility that infection has been induced by other life cycle stages has been experimentally excluded.  相似文献   

3.
通过分析高温变形过程中伴随再结晶晶粒长大的内部位错密度变化,判别不同变形条件下动态再结晶过程的进行形式,研究动态再结晶形式对变形参数的依赖规律,发现:低温大应变速率下,高温变形过程中的再结晶形式以连续性动态再结晶为主;高温低应变速率下,以周期性动态再结晶为主.根据动态再结晶软化与加工硬化平衡,得到反映稳态流动时钛合金流动应力对变形参数的响应,建立具有实际物理意义描述钛合金稳态流动本构关系的Arrhenius型方程.通过热模拟压缩实验得到800~900℃,0.0005~10 s-1条件下的TC18钛合金高温变形流动应力应变曲线,验证动态再结晶形式的判据模型,并通过DMM耗散效率分布图分析模型的适用性.通过显微组织分析,研究不同变形参数下的高温变形过程中,不同动态再结晶形式对应的再结晶晶粒粗化/细化的特点.通过各变形条件下真应变?=0.8时的稳态应力验证得到的本构模型,并分析应变速率敏感系数的变化规律.  相似文献   

4.
Summary A new C21 furanoterpene, oxygenated at C(8), has been isolated from aSpongia sp.; its structure has been established by chemical and spectroscopic studies. The stereochemistry of tetradehydrofurospongin-1 is discussed.A specimen of the sponge has been deposited at the Western Australian Museum (Catalogue No. WAM 429-81). We thank Miss J. Fromont for taxonomic information.A specimen of the sponge has been deposited at the Western Australian Museum (Catalogue No. WAM 483-82). We thank Professor Bergquist for taxonomic information.  相似文献   

5.
Summary Carbonic anhydrase (CA) activity has been localized histochemically by Hansson's method in Malpighian tubules ofCulex pipiens. The enzyme has been observed on membranes of the cytoplasmic inclusions of Malpighian cells; no CA activity has been found in other cytoplasmic structures. The possible meaning of the localization of the enzyme is discussed.  相似文献   

6.
Summary A preparative method for the isolation of lanatoside D has been developed, and fundamental pharmacological characteristics of the pure compound have been established.The genuine glycoside has been converted to desacetyllanatoside D.  相似文献   

7.
以某煤机公司的采煤机截割部可靠性研究项目为依托,研究了计算机虚拟仿真中的关键技术,提出了保证仿真精度、提高仿真速度、缩短仿真时间的具体措施,大大提高了Pro/E、MATLAB、ADAMS和ANSYS四款软件协同仿真的可操作性;发现了该采煤机截割部的薄弱环节,如行星架刚度不足、摇臂壳体出现局部应力集中等;在仿真的基础上对壳体结构进行了改进,得到了优化的采煤机截割部传动机构,保证了截割过程的可靠性,对降低研发成本,节省研制时间,提高产品质量具较强的实用价值。  相似文献   

8.
Structure-based drug discovery has proven useful in improving and shortening the drug development process. The approach of structural genomics to study a large number of targets in parallel has been commonly applied to protein families and even whole genomes. Paradoxically, although membrane proteins represent the largest type of drug targets, up to 70% today, determination of their structure has been modest compared to that of soluble proteins. Because membrane proteins are important for drug discovery an emphasis has been placed on developing technologies and methods to determine membrane protein structures. Several structural genomics initiatives have been established, focusing on the structural biology of membrane proteins. Received 31 May 2006; received after revision 5 July 2006; accepted 9 August 2006  相似文献   

9.
An extractive fibrinolytic enzyme has been characterized and found to belong to the class of vascular plasminogen activators. The agent has been found to have an antithrombotic action in the rabbit.  相似文献   

10.
Summary The active principle ofPsilocybe mexicana Heim, a mexican mushroom with hallucinogenic properties, has been isolated in crystalline form. The compound has been given the namePsilocybin; it possesses indole characteristics and contains phosphorus. A second substance, closely related toPsilocybin but found only in traces, has been calledPsilocin.  相似文献   

11.
Summary The activity of alkaline phosphatase in the various tissue components of the regenerating skin of a cat-fish has been studied. A marked increase in alkaline phosphatase activity in the cells of migrating epithelium has been correlated with their highly active state. High alkaline phosphatase in the basal cells after 2 days has been found to have played an important role in cell multiplication and differention. The functional significance of this enzyme is discussed in relation to the granulation tissue formation.  相似文献   

12.
Crustacean neuropeptides: structures, functions and comparative aspects.   总被引:5,自引:0,他引:5  
R Keller 《Experientia》1992,48(5):439-448
In this article, an attempt is made to review the presently known, completely identified crustacean neuropeptides with regard to structure, function and distribution. Probably the most important progress has been made in the elucidation of a novel family of large peptides from the X-organ-sinus gland system which includes crustacean hyperglycemic hormone (CHH), putative molt-inhibiting hormone (MIH) and vitellogenesis (= gonad)-inhibiting hormone (VIH). These peptides have so far only been found in crustaceans. Renewed interest in the neurohemal pericardial organs has led to the identification of a number of cardioactive/myotropic neuropeptides, some of them unique to crustaceans. Important contributions have been made by immunocytochemical mapping of peptidergic neurons in the nervous system, which has provided evidence for a multiple role of several neuropeptides as neurohormones on the one hand and as local transmitters or modulators on the other. This has been corroborated by physiological studies. The long-known chromatophore-regulating hormones, red pigment concentrating hormone (RPCH) and pigment-dispending hormone (PDH), have been placed in a broader perspective by the demonstration of an additional role as local neuromodulators. The scope of crustacean neuropeptide research has thus been broadened considerably during the last years.  相似文献   

13.
针对我国姿态控制和轨道控制液体火箭发动机推进荆输送系统,围绕蓄压式燃气发生器内弹道预计开展研究。探讨了喷管在超临界状态和亚临界状态下其内部燃气流动的变化规律;分析了燃气发生器工作结束后在对流换热和稳态导热条件下燃气发生器和储气瓶内高温燃气与外界环境的换热过程;编写了内弹道计算程序,在试验论证的基础上,表明该程序可初步预计蓄压式燃气发生器内弹道性能。  相似文献   

14.
基于计算流体力学,借助软件Fluent建立了高压气体检测空管体暗伤的简化模型,并对暗伤处的流场进行了数值模拟分析,针对被氧化膜覆盖的暗伤进行检测,对提高检测的速度和准确性具有十分的积极意义。  相似文献   

15.
应用网络空间点模式分析方法中的最邻近分析方法以及集聚分析方法,对1949年至2006年我国东南沿海地区热带气旋登陆点进行了分析研究。结果表明:我国东南沿海地区热带气旋登陆点在空间上倾向于集聚分布。根据集聚分析的结果将我国东南沿海地区划分为五个区段,其中登陆频率最高的为广东省雷州半岛到阳江段。本研究中的分段方法与传统方法比较表明,传统的经验分类方法注重的是行政区界限,空间统计方法的分段统计意义明显,分段更加科学合理。  相似文献   

16.
Summary The existence of phosphoribomutase and 5-phosphoriboisomerase has been demonstrated in isolated cellular nuclei from rat liver and swine kidney. Phosphoribomutase has been shown to require Mg-ions for optimal activity.  相似文献   

17.
Crustacean neuropeptides: Structures,functions and comparative aspects   总被引:7,自引:0,他引:7  
In this article, an attempt is made to review the presently known, completely identified crustacean neuropeptides with regard to structure, function and distribution. Probably the most important progress has been made in the elucidation of a novel family of large peptides from the X-organ-sinus gland system which includes crustacean hyperglycemic hormone (CHH), putative molt-inhibiting hormone (MIH) and vitellogenesis (=gonad)-inhibiting hormone (VIH). These peptides have so far only been found in crustaceans. Renewed interest in the neurohemal pericardial organs has led to the identification of a number of cardioactive/myotropic neuropeptides, some of them. unique to crustaceans. Important contributions have been made by immunocytochemical mapping of peptidergic neurons in the nervous system, which has provided evidence for a multiple role of several neuropeptides as neurohormones on the one hand and as local transmitters or modulators on the other. This has been corroborated by physiological studies. The long-known chromatophore-regulating hormones, red pigment concentrating hormone (RPCH) and pigment-dispending hormone (PDH), have been placed in a broader perspective by the demonstration of an additional role as local neuromodulators. The scope of crustacean neuropeptide research has thus been broadened considerably during the last years.  相似文献   

18.
Summary Based on general observations on gas production in sanitary landfills, properties of some important landfill gases are discussed, especially with regard to the potential heat recovery. It has been shown, based on practice oriented considerations, that the utilization of landfill gases can be worthwhile even in small landfills. A scheme has been given which shows all the possibilities for collection, pretreatment, storage and combustion of the gases. The question of energy storage and energy utilization has also been addressed. The scheme has been discussed, as well as some of the processes, using the example of the hot water generation plant in the Croglio sanitary landfill in Tessin (Switzerland).Calculation of the running costs shows that this plant, which is designed for a 335 MJ/h production, is working economically.  相似文献   

19.
A series of experiments has been carried out on the flowing of suspended human erythrocytes into glass-tubes whose diameters varied between 30 mum and 1 mm. Thus, the Fahraeus and Fahraeus-Lindqvist effects emergence fields have been drawn, and it has been shown that, contrary to a widely admitted hypothesis, the Fahraeus effect does not account for the Fahraeus-Lindqvist effect.  相似文献   

20.
核受体的研究近几年已有飞速的发展。LXRa(Liver X Receptor a)是一种与脂类代谢有关的核受体。研究发现LXRa的靶基因具有调节脂类的吸收、运输、转化和生物合成的功能,此外,LXRa在糖类的代谢等方面也有重要的调控作用。研究结果表明LXRa与动脉粥样硬化的发生有非常密切的关系。目前利用LXRa为靶标进行抗动脉粥样硬化药物筛选已经成为一个重要的研究方法。  相似文献   

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