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991.
Four oil families are identified in the southern Gulf of Suez, through high-resolution geochemical studies including gas chromatography, gas chromatography-mass spectrometry, and carbon isotope analyses. Biological features characterize oils in family 1a, suggesting tertiary carbonate source rocks for these oils, rich in type II organic matter and deposited under anoxic depositional environment. Family 1b oil shows minor variations in the source of organic matter and the depositional environment, as it was derived from carbonate source rock with more algal and bacterial contribution and minor input of terrestrial organic sources, deposited under less saline condition compared to family 1a oil. Family 2 oil, although genetically related to family 1a oil, has some distinctive features, such as diasterane to sterane and pristane to phytane ratios, which suggest clay-rich source rocks and a more oxic depositional environment. Also, the lack of oleanane indicates pre-tertiary source rocks for this oil. In contrast, family 3 oil is of mixed sources (marine and non-marine), generated from low sulfur and clay-rich source rock of tertiary and/or younger age. Family 4 oil seems to be mixed from family 1b and family 3 oils, sourced mainly from carbonate source rocks rich in clay minerals with algal and bacterial contributions. Family 4 oil is highly mature, family 1b oil lies within equilibrium values (peak oil generation stage), while the other families are more or less near equilibrium. 相似文献
992.
介绍了垫层上载荷试验的类型,通过工程实例对不同类型垫层上的载荷试验应注意的问题进行了分析和探讨,这对通过载荷试验确定双层地基承载力具有一定的实际意义,可供同类工程参考借鉴。 相似文献
993.
[Correction Notice: An erratum for this article was reported in Vol 20(2) of Canadian Journal of Behavioural Science Revue canadienne des Sciences du comportement (see record 2007-09831-001). The abstract accompanying the original article was incorrect; the correct abstract (in French) is presented in the erratum.] We know little about individuals who are declared unfit to stand trial and/or not guilty by reason of insanity. The few existing studies are characterized by methodological weaknesses, notably by short follow-up periods and a lack of external validity. The present investigation, which aims to evaluate and explain readmissions that occurred during a seven- to nine-year period, corrects only some of these weaknesses. Sixty-one per cent of the subjects were rehospitalized during the period of study. It proved difficult to identify the factors associated with readmission. However, males with a diagnosis of schizophrenia and who had committed violent crimes were found the most likely to be readmitted. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
994.
Advanced high-energy plasma systems are being used to achieve the benefits of the high-velocity oxy-fuel (HVOF) system without
losing the inherent advantages of plasma for coating of gas turbine parts. MCrAlY coatings play a very important role in the
performance and reliability of gas turbine components. One of the important considerations for next generation of gas turbines,
which have more demanding conditions and need to withstand ever increasing operating temperatures, is that they should possess
very low oxygen content levels in the coating. Low oxygen content coatings are applied by the expensive low-pressure plasma
spray (LPPS)/vacuum plasma spray (VPS) technique for critical components in aero- and land-based gas turbines. This work deals
with the development of low-cost LPPS equivalent coatings (having low oxygen content) using the high-energy high-velocity
plasma spray (HEHVPS) gun and inert gas shroud. A comparison has also been made with CoNiCrAlY coatings by HVOF. 相似文献
995.
金代朔州崇福寺观音殿是具有典型厅堂型建筑特征的金代佛寺建筑之一,其地盘形式采用减柱造,将前金柱四根全部减掉,形成了此殿特殊的双重人字叉手梁架形制。 相似文献
996.
Presents some brief remarks from the editor of the Journal of Educational Psychology regarding his goals for the Journal, and noting the decline in membership in Division 15. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
997.
在搜集国内外有关资料的基础上,通过对混凝土在多轴应力作用下的徐变与强度关系分析,说明在多轴应力状态下不能简单地采用叠加原理。展示了新的三轴徐变量测仪器及其徐变试验成果以及2组多轴与单轴应力状态下的徐变恢复试验成果,并对试验数据进行比较分析,得到多轴应力状态下徐变恢复与应力大小以及持荷时间之间的规律,证实了多轴应力状态下的徐变恢复与已经产生的压缩徐变有密切的关系。 相似文献
998.
In this study, distribution and history of residual stresses in plaque-like geometries are simulated based on linear thermoviscoelastic
model, which helps to understand the mechanics and evolution of the residual stresses in the injection molding process. The
numerical calculation of direction, combined with the specified boundary conditions. Results show that the stress variation
across the thickness exhibits a high surface tensile value changing to a compressive peak value close to the surface, with
the core region experiencing a parabolic tensile peak. Residual stress distribution throughout the thickness is almost same
along the flowpath and the final residual stresses value near the gate is lower than the value near the end of flowpath. 相似文献
999.
1000.
Fumio Negoro 《Knowledge》2003,16(7-8):383-397
The purpose of our study is to build up relationships between requirement and source programs with our originally thought-out rules. When other rules to be derived from these original rules are applied to software development, even a single instruction in a programming language could be determined, and the program would satisfy the requirement. More specifically speaking, these rules will turn into a formula or a prototype of software programs. Hence, when the variables in the requirement are placed in the formula, we can get a required program in an automatic way. 相似文献