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1.
近年来澜沧江公司对安全生产工作采取了强有力手段,安全生产基础不断夯实。如何将安全工作推进更深的层次,如何把控"准入关",将信用评价纳入安全生产不失为一个行之有效的方式。安全信用评价是建立水电工程施工安全信用体系的重要手段,能够促进整体行业安全管理水平的提升。  相似文献   
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 A cell vertex finite volume method for the solution of steady compressible turbulent flow problems on unstructured hybrid meshes of tetrahedra, prisms, pyramids and hexahedra is described. These hybrid meshes are constructed by firstly discretising the computational domain using tetrahedral elements and then by merging certain tetrahedra. A one equation turbulence model is employed and the solution of the steady flow equations is obtained by explicit relaxation. The solution process is accelerated by the addition of a multigrid method, in which the coarse meshes are generated by agglomeration, and by parallelisation. The approach is shown to be effective for the simulation of a number of 3D flows of current practical interest. Sponsored by The Research Council of Norway, project number 125676/410 Dedicated to the memory of Prof. Mike Crisfield, a respected colleague  相似文献   
3.
Decreasing carboxyl retention in deposits from the glow region of an acrylic acid plasma was measured by X-ray photoelectron spectroscopy and chemical derivatisation as the collection distance from the monomer vapour inlet was increased. Volatilisation of plasma polymerised acrylic acid was detected after trifluoroethanol derivatisation; this is correlated with evaporation of low molecular weight components observed previously.  相似文献   
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Primary care physicians can easily incorporate efforts toward the primary and secondary prevention of family violence into their practices. By designing a preventive effort using the phases of the family life cycle, a developmentally appropriate system of prevention is created. The anticipatory guidance at each (annual) visit acknowledges family transitions and assures the family that abuse is a health issue and that the physician is a resource for issues of violence prevention. Using the FLC, the first phase is Coupling, when there is a risk of partner violence that continues as long as there is a partnership. Pregnancy and childbirth bring concerns of child neglect and battery. Older children are at additional risk for child sexual abuse. As families age, risks develop for elder abuse, too. The regular discussion of these issues raises the awareness that the potential for family violence continues over the life span and allows the physician opportunities to assess the risk of violence in that family and make appropriate preventive referrals. Primary care physicians are optimally positioned to address violence and its prevention in the office: they know and care for family units over time. Physicians are respected and trusted advisors who can become effective in preventing violence.  相似文献   
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Existence conditions are given for maximum likelihood (ML) parameter estimates for several families of 2-parameter software-reliability Poisson-process models. For each such model, the ML equations can be expressed in terms of one equation in one unknown. Bounds are given on solutions to these one equation problems to serve as initial intervals for search algorithms like bisection. Uniqueness of the solutions is established in some cases. Solutions are also tabulated for certain simple cases. Results are given for ungrouped failure data (exact times are available for all failures). ML estimation problems for such a situation are treated as limiting cases of problems based on failure times grouped into intervals of decreasing mesh  相似文献   
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水蒸汽喷射泵系统实用设计软件的开发   总被引:3,自引:0,他引:3  
本文在Turboc环境下开发了多级蒸汽喷射泵系统的设计软件,该软件包括了压缩比优化分配、单级喷射泵结构尺寸设计和冷凝器的结构尺寸设计等内容,使设计人员能够根据具体的工艺条件,快速地完成多级喷射泵系统的设计,对于提高多级喷射泵系统的工作稳定性、节省能源具有实际意义。  相似文献   
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Previous solid state analyses of sintering in Ti4+-doped-commercial alumina are shown to be in error because a liquid phase exists in the appropriate region of the Al2O3−TiO3−Na2Ophase diagram at least by 1350°C, a temperature lower than that at which "solid state" studies were conducted. It is suggested that liquid-phase sintering is a much more common occurrence than was realized formerly.  相似文献   
10.
The results presented in the literature, which attempt to elucidate the mechanisms by which triglyceride oils are bleached by earths, are reviewed. The impact of this work and how the mechanistic proposals affect changes in oil properties are considered, with particular emphasis on the needs of the palm oil processor. Important properties include color, metals and phosphorus content and oxidative stability of the oil. Investigations made in our own laboratories have been aimed at elucidating the effect of varying physical and chemical properties of the bleaching earth on the quality of bleached and deodorized oils. Techniques used in this work are pore-size distribution, surface area, scanning and transmission electron microscopy and a variety of chemical and X-ray analysis methods. The ability to vary such parameters in montmorillonite clays by alteration of process conditions to give materials with specific performance characteristics is demonstrated. Comparisons are made between acid-activated montmorillonites and other clay types.  相似文献   
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