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51.
Electron microscopic study was performed in the experiments on the rat liver while intravenously administering E. coli endotoxin. The dynamics of ultrastructural disorders during endotoxemia has been established and the role of "Kupffer cell-hepatocyte" microsystem in the liver detoxification function is shown.  相似文献   
52.
We review, unify and extend work pertaining to evaluating mode mixity of interfacial fracture utilizing the virtual crack closure technique (VCCT). From the VCCT, components of the strain energy release rate (SERR) are obtained using the forces and displacements near the crack tip corresponding to the opening and sliding contributions. Unfortunately, these components depend on the crack extension size, Δ, used in the VCCT. It follows that a mode mixity based upon these components also will depend on the crack extension size. However, the components of the strain energy release rate can be used for determining the complex stress intensity factors (SIFs) and the associated mode mixity. In this study, we show that several—seemingly different—suggested methods presented in the literature used to obtain mode mixity based on the stress intensity factors are indeed identical. We also present an alternative, simpler quadratic equation to this end. Moreover, a Δ-independent strain energy release based mode mixity can be defined by introducing a “normalizing length parameter.” We show that when the reference length (used for the SIF-based mode mixity) and the normalizing length (used for Δ-independent SERR-based mode mixity) are equal, the two mode mixities are only shifted by a phase angle, depending on the bimaterial parameter ε.  相似文献   
53.
This article describes an evaluation of six different methods for prioritizing software requirements. Based on the quality requirements for a telephony system, the authors individually used all six methods on separate occasions to prioritize the requirements. The methods were then characterized according to a number of criteria from a user's perspective. We found the analytic hierarchy process to be the most promising method, although it may be problematic to scale-up. In an industrial follow-up study we used the analytic hierarchy process to further investigate its applicability. We found that the process is demanding but worth the effort because of its ability to provide reliable results, promote knowledge transfer and create consensus among project members.  相似文献   
54.
An efficient, accurate and practical process for prioritising requirements is of great importance in commercial software developments. This article improves an existing cost-value approach in which stakeholders compare all unique pairs of candidate requirements according to their value and their cost of implementation. Techniques for reducing the required number of comparisons are suggested, thus making the process more efficient. An initial approach for managing requirements interdependencies is proposed. A support tool for the improved process has been developed to make the process more practical in commercial developments. The improved process and its support tool have been applied and evaluated in an industrial project at Ericsson Radio Systems AB. The results indicate a pressing need for mature processes for prioritising requirements, and the work presented here is an important step in that direction.  相似文献   
55.
An experimental and theoretical investigation was made to find out the reasons for the drop in shell-and-tube condenser performance when replacing R22 with a zeotropic mixture R407C. Measurements show that at lower condenser loads the reduction in performance can be as large as 70% compared to the full condenser load. Calculation results are compared with experimental results for two different condensers, one with micro-finned tubes and one with 3-D finned tubes. Calculations show that the degree of mixing of the newly formed condensate on a tube and the drained condensate is a factor influential enough to explain the performance drop. 3-D finned tubes seem to have better mixing in the condensate than integral finned tubes.  相似文献   
56.
NG 《电脑》2014,(9)
正冒险与征服是环塔的魅力,团结与互助是环塔的人文关怀,热心公益更是环塔重要的一种精神……2014年6月6日,经过车手勇士们13天的拼搏与汗水,中国环塔(国际)拉力赛终于在哈密顺利的落下了帷幕。这次比赛中,感恩车队获得了不俗的战绩,感恩车队车手李铁军赢得ATV组亚军,捧得银牌将杯。虽然与冠军失之交臂,略显遗憾,但是感恩车手们付出的努力,都是有目共睹的。冒险与征服是环塔的魅力,团结与互助是环塔的人文关怀,热心公益  相似文献   
57.
58.
NG 《电脑》2014,(6):212-213
正纵观当前汽车内饰行业,群雄并起,大有逐鹿中原之势;但难有一家企业从中脱颖而出,雄霸天下。在上海俊达看来,这是一个重要的机遇期。由2012年开始,上海俊达就已经在打造专车的专属品牌,力图通过整合规划资源,建立完整的专车定制模式与品牌分级体系。  相似文献   
59.
NG 《电脑》2014,(9)
正鱼龙混杂、以次充好、真假难辨……一个个令人生畏的标签,对于隔热膜行业从业者来说,却已是司空见惯。如何在这样的环境中更好地保护消费者的切身利益,也便成为了有担当的企业、品牌日常工作的重要组成部分。MAXFFOTEC美富特2.0版电子质保系统的上线,在为消费者及MAXFFOTEC富美特代理商、经销商带来更好的权益保护的同时,也提升了品牌形象。  相似文献   
60.
The potential of buccal mucosa as a site for systemic absorption has attracted increased attention in recent years creating a need for new predictive in-vivo models. The aim of this study was to evaluate anaesthetised and conscious Göttingen mini-pigs as a model for buccal drug absorption by testing pH-dependent absorption of metoprolol from a solid dosage form. Buccal tablets buffered to pH 6.2 and pH 8.9, oral liquid and intravenous injection were tested in four conscious and anaesthetised Göttingen mini-pigs in a non-randomised cross-over study. Blood samples were collected and processed before analysis by ultra-performance liquid chromatography with tandem mass spectrometry detection. An ex-vivo flow retention model was applied to study release and retention of the bioadhesive buccal tablets. The Tmax obtained from the two buccal conscious groups (55?±?5 and 35?±?5?min) were significantly different to the buccal anaesthetised groups (120?±?0 and 165?±?15?min) for buccal tablet pH 6.2 and pH 8.9, respectively. Also, the absolute bioavailability from the anaesthetised buccal tablet pH 8.9 (20.7?±?4.0%) had a significant increase compared to all other buccal tablet groups. In conclusion, this study showed a pH-dependent absolute bioavailability of metoprolol when administrated as bioadhesive buccal tablets to anaesthetised mini-pigs. The anaesthesia was found to delay the time to reach maximal plasma concentration of metoprolol as compared to the conscious pig model when administrated as buccal tablets.  相似文献   
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