对我国压力容器用钢标准的一些探讨

文章就我国现行压力容器用钢标准的发展情况以及现状进行了阐述,通过对压力容器用钢标准学习,对我国压力容器用钢标准进一步深刻的了解,对设计人员在压力容器设计中在材料的选择上有很大的帮助。     

压力容器非概率可靠性设计方法

为解决压力容器概率可靠性设计分布函数难以确定的问题,采用区间理论,将有边界限制的压力容器筒体内径、应力及载荷等参数用区间变量来描述。通过泰勒级数展开、中心复合实验设计以及顶点法3种方法对压力容器进行非概率可靠性设计。结果表明:常规压力容器设计结果比较保守,采用非概率可靠性设计能够获得轻量化结果。由此,引入区间模型的压力容器可靠性设计,降低了对原始数据的要求,优化了设计结果。     

压力容器设计若干技术问题解析

随着压力容器设计技术的发展,目前在压力容器设计中,也会时常出现出现一些与技术相关的问题,由此导致压力容器的设计出现各种结构或者是技术不合理的现象,不仅给生产厂家造成不必要的材料损失,而且生产的压力容器面临着安全性能挑战。因此在本文中,结合自身多年的实践经验,对压力容器设计中存在的技术问题进行探讨和分析,并提出相应的解决措施,希望能够规避设计技术问题,提高压力容器的生产质量和效益。     

薄壁压力容器的可靠性分析

利用可靠性理论对薄壁压力容器进行了可靠性分析与设计。给出了薄壁压力容器进行可靠性分析所必备理论基础。作为算例,对某间歇蒸馏装置塔底再沸器的筒体厚度,进行了可靠性设计。与传统常规设计分析比较,结果表明:从设计理念上,薄壁压力容器的可靠性设计优于传统常规设计。     

低温压力容器及低温低应力容器的设计探讨

主要介绍了低温压力容器的定义、失效模式及设计中的注意事项,详细分析了形成低温压力容器主要失效模的低温脆裂的必要条件,从而在低温压力容器的设计过程中,通过对设计温度、低温材料选用、结构优化设计、焊接工艺、无损检测等方面的技术优化,确保低温压力容器的使用安全。     

对压力容器的机械强度可靠性设计的简单探讨

对于压力容器一般设计中的不足,可以采用可靠理论性理论中的强度,即:应力干涉模型,将可靠性的设计运用到压力容器中。可靠性设计是假设各个参量都是随机变量,按照实验的数据和工作环境确定出概率特征,再根据压力容器的重要性规定可靠度设计的方法。随着科学技术的快速发展,压力容器的强度和载荷测试的水平也在不断提高,大量的实验结果表明:人们对各个参数随机性的认识在不断增强,所以压力容器的可靠性方法设计是未来不断发展的趋势。     

基于ANSYS的压力容器开孔补强结构可靠性分析与优化设计

在压力容器上开孔,不仅削弱了材料的强度,而且会导致开孔部位局部应力集中,降低压力容器的承载能力,严重影响压力容器的安全性。国标中对压力容器开孔补强设计虽然有一系列规定,但对影响结构安全性诸因素的随机性考虑较少。采用ANSYS有限元软件可靠性分析及优化设计功能相结合的方法,对压力容器开孔补强结构进行可靠性分析并获得应力敏感因素,从而进行相应优化设计。结果表明这种设计方法切实可行。     

低温压力容器设计中关键问题的探究

近年来,随着我国社会经济的飞速发展,液压油气能源的大量运输对低温压力容器的需求量急剧增加。由于金属材料在低温状态下,其硬度和韧性会在一定程度上有所降低,进而使得压力容器难以满足低温压力容器的使用要求,从而导致了低温压力容器爆炸事故的发生,这给社会经济财产和人们的生命安全造成了巨大的损失。本文主要从低温压力容器的设计角度出发,探讨了低温压力容器设计中存在的问题,并结合实际情况,提出了几点制作低温压力容器的意见,以期能够为低温压力容器制作提供参考、借鉴。     

浅谈如何提高压力容器设计质量

压力容器在日常生活和化工生产中应用较为广泛,压力容器设计质量的好坏直接影响到设备安全性、可靠性、先进性,影响到国民财产和人民生命安全。本文主要针对压力容器设计过程中常见问题,并提出相应的提高质量建议,以期为压力容器设计提供帮助。     

开孔补强方法在压力容器设计中存在问题分析

开孔补强是压力容器设计中的常见结构,开孔的结果不但会削弱容器的强度,而且在开孔的附近会造成很高的局部应力。本文对压力容器设计中常用的补强方法进行总结,并介绍了相关的有限元计算结果,为其更好地应用于压力容器设计领域提供基础。     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the     

Call for Papers

<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with     

Journal of Donghua University ( English Edition) Contents of Volume 31

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