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131.
Yuxin Huang Yuanhui Sun Zhongcheng Li Fancheng Zeng 《Petroleum Science and Technology》2013,31(24):2064-2069
AbstractIn order to investigate the gas generation from the pyrolysis of the crude oil, the thermal pyrolysis simulation experiment of the crude oil under the different geological conditions are carried out by using high temperature and high pressure closed system. The cumulative amounts of gaseous hydrocarbons from the pyrolysis of crude oil are almost the same but the generating activation energy are different under the different media (limestone, mudstone, sandstone). The limestone has the greatest impact on the pyrolysis, followed by the mudstone and the sandstone. In addition, pressure and heating rate have an inhibitory effect on the pyrolysis of crude oil. The experimental results can provide an evidence for source judgment and resource evaluation of natural gas in marine strata in China. 相似文献
132.
133.
从聚乙烯醇薄膜的截流率、膜分离系数、耐老化性、光学性能、力学及吸水性能、气体渗透性、膜对污染物的阻挡、导电性、阻醇性、物质的选择性等不同方面，介绍了近几年来国内外的科研单位采用各种不同的研究方式对聚乙烯醇薄膜的各种性能进行研究的情况。可知目前国内外对聚乙烯醇薄膜的研究十分活跃。 相似文献
134.
为了定量研究降雨时分流制雨水管网滞留污染物占总污染物的比例,对某研究区域雨水管网中的滞留污染物定期取样检测,并根据研究区域的基础数据建立SWMM模型。同时,提出了一种雨水管网滞留污染物的计算方法,即以检测到的雨水管网污染物浓度及充满度计算滞留污染物质量。将滞留污染物数据输入SWMM模型中,分析对比有无滞留污染物的管网排放口污染物浓度的变化情况。模拟结果表明,在1年一遇的降雨条件下,雨水系统内的滞留污染物对COD、NH3-N、TP总污染负荷的贡献率分别为43. 30%、92. 75%、58. 83%,雨水管网滞留污染物占雨水管网总污染物的比例较大。 相似文献
135.
Massive commodity transactions lead to enormous virtual water and water pollution transfer; this phenomenon will be intensified within the process of Regional Comprehensive Economic Partnership (RCEP) enforcement. This study applied multi-regional input–output and scenario simulation approach to reveal the virtual water elements flow, while exploring the trade structure optimisation roadmap for China. Results unveiled that China was a virtual water net exporter (9.17 billion tons), also the largest importer of water pollutants (N 622456 tons and P 136110 tons) among RCEP countries in 2015. In order to alleviate the water pressure in China, the textiles and other manufacturing industries should be limited, while the service industry is encouraged. Optimal scenario can realize 29.8% water conservation and 8% water pollutants reduction and also achieve a 36.5 million dollars trade volume increase. This research improves trade-off balance between water environment and economy at multi-regional level and accelerates green trade in economic partnerships globally. 相似文献
136.
《International Journal of Hydrogen Energy》2023,48(46):17565-17576
Strict requirements for cost and reliability of compressed gaseous pressure vessels as on-board hydrogen storage necessitates in-depth understanding on the mechanical responses of the composite structure. General numerical methodology to assess this involves a two-step setup: composite layup generation and mechanical property calculation, which becomes highly time and resource-consuming, particularly if multiple designs are scanned for optimization. This study presents a multi-functional analytical tool, combining both aforementioned steps in a single modeling framework. The model enables quick prediction of the strain/stress distribution in correlation with uncomplicated inputs describing the layup design, i.e. stacking sequence with desired winding angles. Additionally, the mechanical evaluation specially focuses on the dome region whose calculation has hardly been inspected analytically in the literature. The results are validated against a three-dimensional finite element calculation implemented in Ansys Workbench, showing qualitative and quantitative agreement. Overall, the study paves the way for composite tank design using analytical approaches, with easy implementation, minimum computational cost and great transparency. 相似文献
137.
Covalent organic frameworks (COFs) are promising solid absorbents for the treatment of gaseous iodine. However, extensive efforts are still focused on empirical optimizations of specific binding sites and pore structures in COFs, and the chemical control of gaseous iodine uptake on COFs remains challenging. In this study, the chemically triggered sorption properties of COF-300 for I2 vapors at the single-particle level with the dark-field microscope (DFM) are explored. The present operando single-particle DFM imaging method enables the direct visualization of an adsorption activity transformation from inactive COF-300 to active solvated COF-300 toward gaseous I2 vapors. Exploiting the useful reaction information from time-lapsed DFM images, the tunable adsorption performance of solvated COF-300 is quantitatively compared by various solvents. The results illustrate that the isopropanol (IPA)-solvated COF-300 achieves the optimum adsorption capacity for I2 among the absorbents. The reaction mechanism is elucidated to be the channel size enlargement and modification of internal surface chemistry in the IPA-solvated COF-300, producing a stable I2/IPA-solvated COF-300 complex after the sorption reaction. The present chemical control of the sorption behavior of COF-300 revealed by DFM opens up a new fundamental paradigm for rationally developing high-performance COF-based absorbents for removing I2 vapors. 相似文献
138.
139.
A rigorous and comparative evaluation of two biomass‐to‐gases (BtG) conversion routes was performed and, according to this outcome, it is suggested which of the options evaluated is most desirable. These options, the hydrogen and synthetic natural gas (SNG) production, were designed in Aspen Plus process simulation software. Sugar cane bagasse was considered as feedstock. Mass and energy balance data were extracted from the simulations, and consequently thermodynamic (exergy analysis), economic (financial and uncertainty analysis), and environmental (CO2 emissions) evaluations were carried out. Exergy and environmental analysis favor the SNG production while the hydrogen route provides higher profits. 相似文献
140.
This paper applies a unique integrated approach to determine the flammability properties of a composite material (epoxy with carbon fibre) and compares its fire behaviour at two different thicknesses (2.1 and 4.2 mm) by performing small scale (thermo‐gravimetric analysis (TGA)/Fourier transform infrared radiation) and meso‐scale tests (cone calorimeter). For small‐scale tests, experiments were conducted in nitrogen using TGA coupled to gas analysis by Fourier transform infrared radiation. These results allow the determination of thermal stability, main degradation temperature and main gaseous emissions released during the thermal degradation. For meso‐scale tests, experiments were carried out using a cone calorimeter with sample dimensions of 100 × 100 mm at five heat fluxes (30, 40, 50, 60 and 70 kW/m2). The results show that the ignition time increases with an increase in the thickness of the material. Relative hazard classification of the fire performance of the current composites has also been compared with other materials using parameters obtained elsewhere. In addition, the effective ignition, thermal and pyrolysis properties obtained from the ignition and mass loss rate experiments for the 4.2‐mm thick samples were used in a numerical model for pyrolysis to predict well ignition times, back‐surface temperatures and mass pyrolysis rates for all heat fluxes as well as for the 2.1‐mm thick samples. Note that the ignition temperature obtained in the cone agrees with the main degradation temperature in the TGA. The flammability properties deduced here can be used to predict the heat release rate for real fire situations using CFD modelling. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献