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1.
Cold working processes due to inhomogeneous and strong plastic deformations result in the formation of residual stresses and texture within the components. The texture evolution has a strong influence on the residual microstresses and produces non-linear d vs. sin2 ψ-curves. The texture evolution and the resulting non-linear d vs. sin2 ψ-curves are calculated here using the Taylor–Bishop–Hill theory and an elastic unloading model. Examples are given for the inverse pole figure and non-linear d vs. sin2 ψ-distributions due to cold torsion of an austenitic steel.  相似文献   
2.
Progesterone pharmacokinetics were analyzed for plasma hormone concentrations ranging from linear to saturated metabolism in lactating Holstein cows with differing daily milk yields. The adequacy of 2-coupled first-order (bi-exponential equation), hyperbolic (Michaelis-Menten equation), and sigmoidal (Hill equation) kinetic models to describe the experimental progesterone pharmacokinetic profiles was examined on a statistical basis. After nonlinear regression and statistical analysis of the data-fitting capability, a simple one-compartment model based on Hill equation proved to be most adequate. This model indicates an enzyme-catalyzed metabolism of progesterone involving cooperative substrate-binding sites, resulting from allosteric effects that yield a sigmoidal saturation rate curve. Kinetic parameters were estimated for 2 groups of lactating Holstein cows with different daily milk yields. We found, for the first time, a remarkable quantitative agreement of the Hill coefficient value with that reported in pharmacokinetic studies involving cytochrome P450, family 3, subfamily A (CYP3A)-mediated reactions in other mammals, humans included. It seems that positive cooperativity makes enzymes much more sensitive to plasma progesterone concentration, and their activities can undergo significant changes in a narrow range of concentration as characteristic of sigmoidal behavior. Therefore, the values of classical pharmacokinetic parameters, such as the elimination constant, half-life, and clearance rate, were found to be highly dependent on the plasma progesterone concentration.  相似文献   
3.
流体包裹体分析在石油地质学中的主要用途之一是利用成岩矿物包裹体资料进行油气运移路径、注入时间和方向的推测、计算与判断。兴隆台潜山油藏烃类包裹体均一化温度整体上呈单峰正态或不对称单峰分布,其主要形成温度为80~100℃,反映各样品具有相近的烃类包裹体形成过程。部分井的双峰温度特征暗示存在2次烃类注入期。储层烃类充注时间距今3~35Ma,可分为2个主要的充注期:距今27~35Ma和3~24Ma,以前者注入作用更强烈。潜山内部油气是由东向西注入的。成藏分为3个阶段:a)沙三段沉积晚期,形成的少量油气进入已逐步发育并定型的圈闭中,沙三末期的短暂抬升导致已聚集成藏的油气遭受一定的氧化形成黑色沥青;b)沙二段、沙一段—东营组沉积期为潜山主要油气聚集期;c)晚第三纪以来的生烃强度较弱。潜山上覆沙四段及沙三段泥岩为良好的封盖层,使油藏得以保存。  相似文献   
4.
为明确济阳坳陷孤西潜山带油气差异富集特征,指导下步油气勘探方向优选,综合利用钻井及地震资料,在潜山地质特征分析的基础上,对潜山构造演化及其对油气差异富集的控制作用进行了研究。结果表明,印支期以来,孤西潜山带经历了晚三叠世挤压抬升剥蚀、早—中侏罗世弱挤压到截凸填凹、晚侏罗世挤压抬升剥蚀、早白垩世左行走滑拉张、晚白垩世挤压抬升剥蚀、古近纪右行走滑拉张高位潜山剥蚀等4期挤压、2期拉张、2期走滑、5期剥蚀的演化过程,并于新近纪整体沉降定型,在孤西潜山带形成高位潜山和低位潜山2类潜山,整体具有“NW向断层控带、NE(EW)向断层控山、垒堑相间”的构造格局。多期构造活动作用的叠加,导致2类潜山在源储对接关系、油藏类型和油气富集特征上具有明显差异,高位潜山斜坡带上古生界和中生界地层油藏最为富集,低位潜山各层系均可成藏,且以古生界构造油藏最为富集,同种类型的潜山由于成藏要素配置关系的不同,其油气富集特征也有所差异。埕中、埕东、孤岛等高位潜山斜坡带地层油藏,孤北、垦利等低位潜山下古生界风化壳油藏及内幕构造油藏和上古生界及中生界构造油藏是下步重点勘探目标。  相似文献   
5.
This paper mainly studies on the biaxial tensile strength and its calculative formula of a special made concrete. According to the Hill theory and the uniaxial tensile experiment results, the expression of the concrete biaxial tensile strength is deduced, which is then combined with experiment data and checked. The result shows: the biaxial tensile strength of this kind of concrete is about 15%-30% lower than its uniaxial tensile strength, and the calculative value is basically consistent with the experiment value, with less than 11% difference. This kind of biaxial tension weakening effect is very important to the structure designs of concrete road. The author suggests further research.  相似文献   
6.
The inhibition of ATP synthesis, proton uptake, and electron transport (basal, phosphorylating, and uncoupled) from water to methylviologen by zaluzanin C indicates that it acts as an electron transport inhibitor. Uncoupled photosystem I electron transport rate was not affected by zaluzanin C; however, uncoupled photosystem II electron flow from water to 2,3,5,6-tetramethyl phenylenediamine and from water to silicomolybdate was inhibited, but electron transport from diphenylcarbazide to silicomolybdate was not affected. We conclude that the site of inhibition by zaluzanin C is located at the oxygen evolution level.  相似文献   
7.
通过对顶山隧洞进出口水工模型试验研究,验证隧洞进出口各种工况下的水流流态和消力池的消能效果及水流对下游渠道可能产生的冲刷影响;试验测得隧洞进出口水流流态基本平稳,隧洞出口的消力池末端流速不大,不会对下游渠道产生大的冲刷破坏。  相似文献   
8.
Completed in 1970, this residential building on a prime London site is recognised as a pioneering example of the British High Tech style. More importantly for this issue of AD, it was designed so that leaseholders could devise their apartments' layouts themselves, with maximum allowance for future adaptation – in contrast with the high-spec, investor-driven typology that is prevalent for such sites today. Writer and architect Edwin Heathcote describes the building's structure, the co-ownership housing society model that made it possible, and how it has fared over time.  相似文献   
9.
:1995 年河津市龙门山麓发生特大暴雨洪水,对黄河禹门口提水工程二级干渠边山渠段及部分建筑物造成破坏。本文在分析该工程水毁原因和处理措施的基础上,对如何进行边山渠道设计提出了几点见解。  相似文献   
10.
    
Brussels architecture and art collective Rotor's approach involves research through physical immersion in each project site. By engaging with people's lived realities and reinvesting knowledge in the places where it was acquired, they have gained particular prominence in the flourishing reuse sector. Rotor's resident researcher Alison Creba and co‐founder Lionel Devlieger here describe how they work, and present some of their projects, in Belgium and Sicily.  相似文献   
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