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101.
Polystyrene‐fullerene compositions containing up to 0.45 mol % (3 wt %) fullerene C60 were investigated. It was established that the addition of fullerene to polystyrene (PS) leads to an increase of molecular packing density and so influences the transport of small molecules through the polymer films. Gas diffusion through films of PS‐fullerene compositions is slower than through PS films, and gas separating properties of compositions are higher. Dielectric studies showed that the fullerene is distributed as clusters in the polymer matrix of solid composition prepared from a toluene solution of PS and fullerene. Heating without air to the temperature higher than PS glass transition leads to increasing relaxation time of α‐transition in PS of compositions containing >0.15 mol % (1 wt %) fullerene. This effect is caused by rather strong interaction of PS chains via fullerene molecules entered into the PS‐fullerene complex. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 2946–2951, 2002 相似文献
102.
We have studied the CO2/CH4 mixed gas permeation through hollow fiber membranes in a permeator. An approach to characterize the true separation performance of hollow fiber membranes for binary gas mixtures was provided based on experiments and simulations. Experiments were carried out to measure the retentate and permeate flow rates and compositions at each outlet. The influences of pressure drop within the hollow fibers, non-ideal gas behavior in the mixture and concentration polarization were taken into consideration in the mathematics model. The calculation results indicate that the net influence of the non-ideal gas behavior, competitive sorption and plasticization yields the calculated CO2 permeance in a mixed gas permeator close to that obtained in pure gas tests. Whereas the CH4 permeance is higher in the mixed gas tests than that in the pure gas tests, as the plasticization caused by CO2 dominates the permeation process. As a result, the CO2/CH4 mixed gas selectivity is smaller than those obtained in pure gas tests at equivalent pressures.The calculated membrane performance shows little changes with stage cut if the effect of concentration polarization is accounted for in the calculation. The integration method developed in this study could provide more accurate characterizations of mixed gas permeance of hollow membranes than other estimation methods, as our model considers the roles of non-ideal gas behavior and concentration polarization properly. 相似文献
103.
Flory–Huggins interaction parameters, λ, were determined for a series of probes in an amine cured epoxy resin matrix (433–493 K) and its precursors (324–363 K) by inverse gas chromatography (IGC). Hildebrand–Scatchard theory was combined with Flory–Huggins theory in order to estimate infinte dilution solubility parameters (δ2) for the matrix and its precursors at 298 K. It was shown that the value of the solubility parameter for the cured resin matrix lies between those of its precursors. Compared to the majority of published work, an unusual aspect of this application of IGC is that solubility parameters have been determined when the stationery phases are (i) small molecules and (ii) a highly crosslinked polymer. Moreover, all possible attempts have been made to ensure equilibrium conditions between probe and stationary phase, and compensation for asymmetry of peak profile has been applied in determining δ2. The solubility parameters estimated by IGC are in good agreement with those calculated by other methods. 相似文献
104.
本文简要介绍了国外在开发超酸性气体过程中遇到的材料选择、腐蚀监测、水化物堵塞、超酸性气的处理和加工等问题所采取的措施和办法。 相似文献
105.
DX型数据采集与无线传输系统能对油井压力、温度、载荷和流量等参数进行自动采集 ,并通过无线传输向总站提供实时参数 ,为及时决策提供信息。数据采集系统采用STD总线 ,测量精度高、故障低 ;无线传输系统采用短波电台和具有自动纠错功能的数传机 ,抗噪能力强、可靠性高。文章介绍了DX型数据采集与无线传输系统的组成、工作原理、功能和主要技术指标 相似文献
106.
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通过对J.J.Arps方程的推导,提出了油气藏产量递减曲线分析的最佳拟合法。用该法可直接求出递减指数N、初始递减率D1及油气递减前的稳定产量Qi,避免了使用试差法的大量运算过程,大大提高了油气藏工程中指标预测的精度。 相似文献
107.
根据加油站效益的增长关系到成品油销售企业生存与发展的重要地位,以及加油站站长职能逐步由管理向经营、经理人转变的实际情况,指出做好加油站的经营管理工作,最大限度地调动加油站站长的工作积极性是企业必须认真研究解决的问题。阐述了调动站长积极性应做好如下工作:建立优胜劣汰的站长选聘机制;赋予站长应有的管理权力;站长实行“特岗特薪”,体现站长责、权、利的统一;制定公平、客观的业绩考核激励机制;强化站长培训,提高站长的综合素质和专业技术水平。 相似文献
108.
节流式差压流量计的发展和现状 总被引:2,自引:0,他引:2
文章介绍节流式差压流量计的特点及标准化进程,煤气流量测量中存在的难点以及正在试图解决的途径。 相似文献
109.
煤气设施防腐实践及影响质量因素分析 总被引:1,自引:1,他引:0
根据近几年三明钢铁公司煤气设施的防腐实践,就影响煤气设施的质量因素进行了分析。 相似文献
110.