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91.
采用热解──催化法使废旧聚乙烯塑料裂解,并对裂解产物进行GC/MS分析.结果表明,废旧聚乙烯塑料的裂解产物主要由正构烷烃、烯烃及少量环烷烃组成.这些化合物均具有重要的回收利用价值.  相似文献   
92.
从晶相组成、晶格缺陷密度、表面羟基含量、晶粒尺寸以及比表面积等方面阐述了热处理温度与TiO2光催化剂结构性质的关系,并就混晶效应、载流子输运/俘获以及尺寸量子效应等对光催化活性的影响进行了讨论。此外,还汇总了对水中典型有机污染物的光催化氧化研究以及相关的催化剂结构性质。  相似文献   
93.
垃圾堆酵对焚烧厂垃圾热值的影响   总被引:6,自引:0,他引:6  
分析了垃圾焚烧厂的渗滤液;基于渗滤液的体积和CODcr值,估算焚烧厂垃圾堆酵对垃圾热影响以及焚烧厂垃圾的适宜堆酵时间,实验结果表明,上海生活垃圾渗滤液是生化性好的高浓度有机废液,堆酵5d,其低位热值〉4600KJ/kg,可直接焚烧。  相似文献   
94.
Thermal modeling techniques constrained by published petrological and thermo-chronometric data were applied to examine late orogenic burial and exhumation at a Variscan suture zone in Central Europe. The suture separates the southern Rhenohercynian zone from the Mid-German Crystalline Rise and traces the former site of a small oceanic basin. Closure of this basin during Variscan subduction and subsequent collision of continental units were responsible for different tectono-metamorphic evolutions in the suture's footwall and hanging wall. Relative convergence rates between the southern Rhenohercynian zone and western Mid-German Crystalline Rise can be inferred from the pressure-temperature-time evolution of the Northern Phyllite Zone. During Late Viséan-Early Namurian times, horizontal thrusting velocities were at least 20 mm/a. Thermal modeling suggests that exhumation of the Mid-German Crystalline Rise occurred temporarily at rates of more than 3 mm/a. Such rapid exhumation cannot be produced by erosion only, but requires a substantial contribution of extensional strain. Exhumation by upper crustal extension occurred contemporaneously with convergence and is explained by continuous underplating of crustal slices and thrusting along faults with ramp-flat geometry. Finally, implications for the tectono-metamorphic history of the study area and the thermal state of the crust during late Variscan exhumation are discussed.  相似文献   
95.
I develop a state-based dynamic model of behavior to demonstrate that size-dependent differences in temperature tolerances are not necessary to account for the activity of small male digger wasps late in the day. In the model, males defend or patrol the nesting area, wait near nests, or feed away from the nesting area depending on time of day, energy reserves and size rank. I assume a large male competitive advantage, so mating opportunities decrease with size rank for territorial or patrolling males and are rare for all waiting males; the costs of patrolling or defense are higher than the costs of waiting. If energy reserves of all males are initially small, all males alternate feeding and territorial or patrolling behavior. If energy reserves are initially large, large males patrol or maintain territories until they risk starvation and leave the area to feed. At this time, smaller males that have conserved their resources by waiting and feeding may defend territories or patrol. I simulate the behavior of three populations representing two species of Microbembex by assuming large initial energy reserves for populations in which males were territorial and small initial reserves for populations in which males patrolled, and then convert the predicted time of activity to temperature using local regressions from field studies. Temporal patterns in the activity of large and small males were similar to those actually observed, and relationships between size and temperature predicted by the model corresponded to most observations and were sometimes positive. Thus, the delayed activity of smaller males does not correspond to activity at higher temperatures and is probably not attributable to size-dependent thermal tolerances, but may represent a temporal displacement of mating activity due to intra-sexual competition and mediated by energetics. The model makes testable predictions on the timing of feeding and depletion of energy reserves in relation to size and initial energy state, and suggests how differences among species may influence the temporal and spatial organization of male mating behavior. Received: 27 February 1997 / Accepted after revision: 26 July 1997  相似文献   
96.
Highly exothermic materials have caused many serious accidents involving storage and transportation, due to being thermally reactive. The safe storage and management of these materials is still a critical problem in many countries. Our aim was to study the thermal hazard of thermal reactive materials, such as a propellant, by employing differential scanning calorimetry (DSC) non-isothermal tests and isothermal tests, and then comparing the kinetic parameters by isothermal and non-isothermal of kinetics. The chosen approach was to obtain reliable thermal decomposition by a safe and effective method, which acquired the kinetic and safety parameters of storage conditions that could be applied as highly exothermic materials' reduction of loss prevention and energy potential for safer design during storage transport and processing operations.  相似文献   
97.
Bisphenol A is one of the basic compounds used in a synthesis of polycarbonates and epoxy resins. Its dust can create an explosive mixture with air under specific circumstances. Therefore, the main goal of this research was to determine explosion characteristics and flammability behaviour of this compound. The complete flammability characteristic requires the determination of the basic parameters of Bisphenol A under fire conditions including Heat Release Rate, speed of combustion, ability to ignite and the temperature of the decomposition range. To establish those parameters, a cone calorimeter was used. The explosion characteristics were tested in a 20-L spherical vessel. Minimum Ignition Energy was tested on MINOR II Apparatus which is a modified Hartman's Tube. In order to identify hazardous substances generated during a fire involving Bisphenol A, a simultaneous thermal analysis that combines thermogravimetry and differential scanning calorimetry was used. The substances obtained from the thermal degradation were analyzed by infrared spectroscope with Fourier transformation. Furthermore, the application of a Purser furnace and gas chromatography with mass spectrometry facilitated the identification of gaseous substances formed during the thermal degradation of Bisphenol A samples.  相似文献   
98.
The heterogeneity of biomass makes it difficult if not impossible to make sweeping generalizations concerning thermochemical treatment systems and the optimal equipment to be used in them. Chemical differences in the structural components of the biomass (cellulose, hemicellulose, and lignin) have a direct impact on its chemical reactivity. The aim of this research was to study the influence of the organic components of the raw material from olive trees (leaves, pruning residues, and wood) in the combustion behavior of this biomass, as well as to find the component responsible for the higher ash content of olive leaves. Accordingly, the study used a thermogravimetric analyzer to monitor the different states and complex transitions that occurred in the biomass as the temperature varied. The decomposition rates of the different samples were analyzed in order to establish a link between each combustion phase and the composition of the raw materials. Two methods were used to determine the hemicellulose and cellulose contents of biomass from olive trees. Significant differences among the results obtained by the different methods were observed, as well as important variations regarding the chemical composition and consequently the thermal behavior of the raw materials tested.  相似文献   
99.
邬岱杰  陈敏 《火灾科学》2015,24(3):151-158
针对现有防火分隔技术的不足,以细水雾幕作为新的防火分隔技术,开展了不同细水雾幕雾特性对衰减热辐射影响的数值模拟研究。通过建立长通道模型,在火源和被保护物体中间设置细水雾幕系统,测量有无细水雾幕及不同细水雾特性条件下被保护侧温度及热辐射强度值,来定性定量研究细水雾幕衰减热辐射的效率。模拟结果表明:细水雾幕可以很好的降低被保护侧空间的温度和热辐射强度;衰减热辐射效率随雾滴粒径的减小,喷雾流量的增大,喷头排数增加而增大;另外,其衰减热辐射效率与喷头布置方式有关,上喷方式明显优于下喷方式。研究结果将对现有防火分隔技术的改善提供帮助和技术支持。  相似文献   
100.
The paper represents some results of comparative analysis of the methods used for processing and interpreting data of adiabatic calorimetry as well as applying it to practical situations. Specifically two approaches are compared – approximate method based on evaluation of simplified kinetics and a more comprehensive, simulation-based method that utilizes the evaluation of more detailed kinetic models.The analysis is focused on two important types of data processing – correction of experimental results on thermal inertia (phi-factor correction) and estimation of adiabatic time to maximum rate (TMR).The most widely cited method for phi-factor correction is considered and its improvement is proposed to enable more precise prediction of the adiabatic time scale. A procedure for phi-factor correction of pressure response is also proposed. The limitations of this enhanced Fisher's method are discussed by comparison with simulation-based method. All the illustrative materials are based on real examples.As an example of application, the simplified method will be used to predict TMR and its limitations will be discussed.  相似文献   
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