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1.
R.-L. Yun Y.-M. Chang C.-H. Lin K.-H. Hu C.-M. Shu 《Journal of Thermal Analysis and Calorimetry》2006,85(1):107-113
In industrial processes, information
on the safety property of chemicals is essentially crucial for safe handling
during unit operations. Ensuring the safe use of combustible or flammable
substances in processes is unlikely without detailed investigations of their
flammability characteristics and related hazards. We studied 3-methyl pyridine
(3-picoline), e.g., flammability limits (LFL/UFL), maximum explosion pressure
(P
max), maximum
explosion pressure rise (dP/dt)max, minimum oxygen concentration
(MOC), vapor deflagration index (K
g),
and characterized the influence of inert steam (H2O)
on critical parameters for 3-picoline/water mixtures at 270°C, 1 atm,
various oxygen concentrations, and vapor mixing ratios (100/0, 30/70, 10/90
and 5/95 vol.%) with a 20-L-Apparatus in simulated conditions, respectively.
The results showed that the flammability characteristics
of 3-picoline(aq) all increased with the oxygen concentration.
However, as the composition of inert steam increased, the flammability parameters
and the degree of fire and explosion hazards were significantly reduced, instead.
This study elucidated the flammability properties of 3-picoline mixed with
inert steam. The conclusions could be applied to proactively prevent the relevant
processes from incurring fire and explosion accidents. 相似文献
2.
B. Roduit Ch. Borgeat B. Berger P. Folly B. Alonso J. N. Aebischer F. Stoessel 《Journal of Thermal Analysis and Calorimetry》2005,80(1):229-236
Summary An advanced kinetic study on the thermal behaviour of pyrotechnic ignition mixtures has been carried out by differential scanning calorimetry using different B/KNO3 mixtures (50:50, 30:70, 20:80) as a model reaction. The experimental conditions applied (isochoric conditions/closed crucibles and isobaric conditions/open crucibles) as well as the composition of the mixtures noticeably influences the relative thermal stabilities of the energetic materials. The kinetic study focused on the prediction of the thermal stability of the different mixtures both in extended temperature ranges and under temperature conditions at which ordinary investigation would be very difficult. Using advanced numerical tools [1], thermal ageing and influence of the complex thermal environment on the heat accumulation conditions were computed. This can be done for any surrounding temperature profile such as isothermal, non-isothermal, stepwise, modulated, shock, adiabatic conditions and additionally for temperature profiles reflecting real atmospheric temperature changes (yearly temperature profiles of different climates with daily minimal and maximal fluctuations). Applications of accurate decomposition kinetics enabled the determination of the time to maximum rate under adiabatic conditions (TMRad) with a precision given by the confidence interval of the predictions. This analysis can then be applied for the examination of the effects of the surrounding temperature for safe storage or transportation conditions (e.g. determination of the safe transport or storage temperatures). 相似文献
3.
4.
Additive hazards model with random effects is proposed for modelling the correlated failure time data when focus is on comparing the failure times within clusters and on estimating the correlation between failure times from the same cluster, as well as the marginal regression parameters. Our model features that, when marginalized over the random effect variable, it still enjoys the structure of the additive hazards model. We develop the estimating equations for inferring the regression parameters. The proposed estimators are shown to be consistent and asymptotically normal under appropriate regularity conditions. Furthermore, the estimator of the baseline hazards function is proposed and its asymptotic properties are also established. We propose a class of diagnostic methods to assess the overall fitting adequacy of the additive hazards model with random effects. We conduct simulation studies to evaluate the finite sample behaviors of the proposed estimators in various scenarios. Analysis of the Diabetic Retinopathy Study is provided as an illustration for the proposed method. 相似文献
5.
In this paper we study a family of stochastic orders of random variables defined via the comparison of their percentile residual life functions. Some interpretations of these stochastic orders are given, and various properties of them are derived. The relationships to other stochastic orders are also studied. Finally, some applications in reliability theory and finance are described. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
6.
This paper presents several applications of the PHI-TEC II that are not commonly associated with adiabatic calorimeters but which have proved to be extremely valuable. These include simulation of a deep oil well for enhanced oil recovery, isothermal calorimetry of a semibatch reaction, catalyst research using flow through reactors (both plug flow and CSTR) with controlled feeds of high pressure liquid and gas.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
7.
Wenbin Lu 《Annals of the Institute of Statistical Mathematics》2008,60(3):545-574
The proportional hazards cure model generalizes Cox’s proportional hazards model which allows that a proportion of study subjects
may never experience the event of interest. Here nonparametric maximum likelihood approach is proposed to estimating the cumulative
hazard and the regression parameters. The asymptotic properties of the resulting estimators are established using the modern
empirical process theory. And the estimators for the regression parameters are shown to be semiparametric efficient. 相似文献
8.
9.
黄土构造节理研究及其应用 总被引:3,自引:0,他引:3
作者发现大量不同力学性质的黄土构造节理后,识别了它们的区域性、系统性特征;认定其两组扭裂面代表新构造应力场最大剪切应力方向,利用黄土构造节理系及由其控制的土层沟槽网络恢复了相应地区Q3-4构造应力场;提出构造节理是黄土区地下水运移的主要通道和赋存的场所;发现构造节理是黄土区地裂缝、滑坡、崩塌和水土流失等地质灾害的构造基础之一,证实构造节理是黄土地层的软弱面,风化和继之而来的应力侵蚀就由此开始,进而逐步塑造黄土碟、穴、井、桥、柱、墙、沟等潜蚀地貌和部分侵蚀地貌。研究黄土构造节理对恢复新构造应力场、帮助预测地裂乃至地震活动、控制水土流失和滑塌灾害、进行工程乃至区域稳定性评价、重新认识黄土潜蚀地貌发育规律、指导干旱半干旱黄土区找水,既有理论意义又有实际意义。 相似文献
10.
本文在多类型复发间隔时间数据下,研究了一类广义半参数风险回归模型的参数估计问题,给出了该模型中未知参数和非参数函数的一种估计方法,并证明了估计量的相合性和渐近正态性.最后利用数值模拟来评估估计量在有限样本下的表现. 相似文献