喷射火焰对容器的热辐射计算

液化气体容器在火灾环境下由于内部压力升高和容器本身强度的下降，爆炸的危险性极大。研究容器在喷射火焰作用的响应规律是预防事故发生的关键。本文研究了由于气体泄漏引起的喷射火焰在有风条件下的火焰形状和温度变化规律，以及对于水平圆柱形容器的热辐射影响，并用编制计算程序进行了数值计算。计算结果表明，容器表面的热辐射随风速、容器表面的位置等因素而变化。风速越大，容器表面的热辐射会减少；轴向距离越大，热辐射减少，周向角度增加，热辐射减少。     

The ISO 14001 certification of a machine-process

Some process machines in industrial manufacturing can be defined machine-process: their operations can be analysed by several points of view independently from the larger manufacturing process where they are included. For a machine-process, an Ems—Environmental management system can be set up and the ISO 14001 certification reached in an ‘earlier application’ way, with the involvement of both supplier/manufacturer and client/user. The ‘earlier certification’ of machine-processes adds new contents to the product, linked to the environment, helping the market of ‘clean technologies’, and fosters the diffusion of ISO 14001 certification among supplying/manufacturing companies and clients/users whose entire process is not yet certified.A case study is presented that has been experienced in Italy. The ‘offer and design’ phase of a port mobile shiploader is completely developed by following the ‘earlier application’ scheme for ISO 14001 certification of a machine process—introduced and explained in the paper. Achieved results are shown, and the perspective of a complete application of the scheme to the following ‘detailed design and assembly’ and ‘operations’ phases of the same machine are outlined. The feasibility of such a new application of ISO 14000 standards is proved, together with its advantages, while the readiness of the market for the new sector of earlier certification of machine-processes is highlighted.     

The safety of obstetrical ultrasound: a review

Ultrasound is a commonly employed imaging modality in obstetrics and is generally regarded as safe to the fetus. Current ultrasound technology, however, has significantly higher output potential than older machines used in most clinical studies, and the safety profile for the increasing use of Doppler, 3-dimensional (D) and 4-D ultrasound with modern machines is unknown. This article reviews the current status of ultrasound safety within obstetrics, including proposed mechanisms of harm, existing scientific and clinical evidence regarding those mechanisms, and considerations of safety for the clinical user. Copyright © 2009 John Wiley & Sons, Ltd.     

上浮式高速冲模设计

介绍了一种上浮式高速冲裁模的设计方法 ,适用于薄板冲裁 ,其在卸料方式、定位方法上有一定的特点     

我校建立灾害经济学学科的重要性

本文回顾了灾害经济学的发展历程,分析了灾害经济学的理论框架及与其他学科的关系,从经济学的角度阐述了建立这一学科的必要性,并探讨了建立这一学科的基础条件.全文从经济学的角度阐述了建立这一学科的必要性.并探讨了建立这一学科所要研究的理论知识.     

对称可识别模型的建立研究

通过三个定理的证明,提出了对称可识别模型,为以后进一步研究和应用对称可识别模型提供理论基础。     

蓝色经济为危机时代培植新经济商业模式

<正>新一代企业家如何能把创新引入市场以保障全体人民的基本需求并使可持续的商业具有竞争性,这是当前经济形势下至关重要的一步。2008年金融海啸后仅几个月,国际劳工组织就报道有5000万人失业。正规行业     

环境污染损害评估方法初探——以某废油污染场地为例

以厦门市一废油污染场地为例,通过现场调查和监测主要污染物,从财产损失、应急处置费用、调查评估费用以及污染修复费用等方面对该污染场地所造成的环境污染损害进行了评估。该场地主要污染物为倾倒的废油和油底废物,部分污染土壤的石油类指标超标。经测算,污染面积为2 440 m2,造成的环境污染损失数额为162.25万元。     

The lumisphere,a new model of pre-biotic evolution

Lyophilization of the amber-colored, fluorescent oils obtained via thermolysis of amino acid mixtures (Lys, Ala, Gly) leads to a cellular-structured material—with an average cell diameter of 50 μm. The cellular aggregates show a resemblance to epithel tissues. Single cellular entities find their analogs in Fox microspheres as well as in the microfossilsIsuasphaera. Short-wave UV (254 nm) irradiation of the aqueous suspensions destroys the cells, whereas suspension in saline solutions (NaCl) offers protection against dissolution by UV light. The fluorescence spectrum of the microscopic preparations containing the highly fluorescent cellular material (“lumispheres”) was registered.     

催化光度法测定环境样品中微量Hg的研究

在酸性介质中,痕量Ｈｇ（Ⅱ）能显著催化空气中的Ｏ２氧化Ｋ４［Ｆｅ（ＣＮ）６］,生成蓝色化合物,反应对Ｈｇ（Ⅱ）为一级,催化反应的表观活化能为６２．９５ｋＪ·ｍｏｌ－１．据此建立了测定痕量Ｈｇ（Ⅱ）的动力学分析法,测定条件为Ｋ４［Ｆｅ（ＣＮ）６］：１．４×１０－３ｍｏｌ·Ｌ－１,［ＣＨ３ＣＯＯＨ］：０．１４ｍｏｌ·Ｌ－１,７５℃．在此条件下,线性测定范围为０．０２—０．７０μｇ·ｍｌ－１．本法重现性好,常见共存离子中除Ａｇ（Ｉ）严重干扰外,其余离子不影响测定．测定了水样及污泥样品中的Ｈｇ含量,结果满意     

The first record of a sauropod dinosaur from Antarctica

Sauropoda is one of the most diverse and geographically widespread clades of herbivorous dinosaurs, and until now, their remains have now been recovered from all continental landmasses except Antarctica. We report the first record of a sauropod dinosaur from Antarctica, represented by an incomplete caudal vertebra from the Late Cretaceous of James Ross Island. The size and morphology of the specimen allows its identification as a lithostrotian titanosaur. Our finding indicates that advanced titanosaurs achieved a global distribution at least by the Late Cretaceous.     

《小窗幽记》的独特价值

晚明陈继儒等辑录的清言小品集《小窗幽记》,充满对人生的回味与领悟,既体现了儒家的积极人生态度,又兼容了佛家超凡脱俗和道家清静无为的智慧,其独特的情感取向和独创的艺术价值为后人展示了晚明文人旷达超脱、陶情遣兴的生活方式,留下了宝贵的精神财富,在中国文学史上具有独特价值。