High-pressure gas-liquid equilibrium of the system carbon dioxide-citral at 50 and 70 °C

Measurements of high-pressure gas-liquid equilibria of the binary system carbon dioxide-citral were carried out in the present work. The knowledge of the phase equilibrium behaviour of this system is relevant with regard to the design and optimization of the supercritical deterpenation process. The measurements were carried out at 50 and 70 °C, in the pressure range 7.8-15.6 MPa, by means of a two-chamber gas-phase recirculation apparatus of 340 cm³. Both the liquid and the gas phase composition were measured. The data at 50 °C measured in this work were compared with literature data, whereas no comparison was possible at 70 °C because of their lack. The experimental data measured in this work were successfully correlated by means of a thermodynamic model based on the Peng-Robinson equation of state.     

双室(层)曝气生物滤池充氧性能及流态特征

研究了双室 (层 )曝气生物滤池 (DBAF)的充氧性能和流态特征 ,结果表明氧传质系数与曝气强度成正比 ,加滤料前后氧传质系数的差别与曝气强度的大小有关 ,曝气强度较低时 ,两者相差4 0 % ,随着曝气强度的增加 ,两者逐渐接近。DBAF可用n值为 8～ 10阶式CSTR描述 ,流态接近推流式反应器。降低水力负荷和增大滤料高度时 ,DBAF的流态更趋近于推流式     

High-pressure gas-liquid equilibrium measurements by means of a double-chamber recirculation apparatus. Data on the system carbon dioxide-limonene at 50 and 70 °C

Measurements of the phase equilibria for the system carbon dioxide-limonene were performed at 50 and 70 °C in the pressure range 8.54-13.34 MPa. Both the liquid and the gas phase composition were measured. The experiments were carried out by means of a two-chamber recirculation apparatus. According to the procedure, in one of the chambers the gas-liquid equilibrium is established, whereas the second one contains only the gas phase which is continuously recirculated through the chambers to reduce time for equilibration. Before sampling, the chambers are separated to avoid disturbances of the equilibrium when reducing pressure during the withdrawal of the gas phase. Experimental data at 50 °C were used for the validation of the experimental method, through comparison with literature data, whereas those at 70 °C are mostly original. The experimental data were successfully correlated by means of a thermodynamic model based on the Peng-Robinson equation of state.     

A microfluidic flow-converter based on a double-chamber planar micropump

A microfluidic flow-converter that transforms an oscillatory flow into a steady-like flow in a reciprocating-type pumping device is successfully developed in this study. The flow quality at the outlet is found to be significantly improved. The present micro-device is composed of two single-chamber PZT micropumps in parallel arrangement and can be fabricated using simple micro-electro-mechanical-system (MEMS) techniques. Based on the concept of the electronic bridge converter, the flow rectification is supported by four passive planar valves. Two operation modes, in-phase and anti-phase, were used to test the performance of the present device. In addition, the flow characteristics at the outlet were examined by an externally triggered micro-PIV system. The results reveal that the current flow-converter provided both high volume and smoothly continuous flow rates at the outlet when it was in anti-phase mode. Moreover, the volume flow rate was linearly proportional to the excitation frequency within a specific frequency regime. This indicates that the flow-converter was easily operated and controlled. The present microfluidic flow-converter has great potential for integration into future portable micro- or bio-fluidic systems.     

双生长室超高真空化学气相淀积系统的研制

本文介绍了中国科学院半导体研究所的双生长室超高真空化学气相淀积系统的工作原理、技术参数、结构、性能及特点。该系统具有双生长室、引入准分子激光和多态源等主要优点,是IV族半导体材料生长和研究的强有力工具。     

使用“双腔负压法”实现激波管高声压级校准

提供了在激波管中使用“双腔负压法”实现高声压级校准的方法,该方法克服了静电激励法高声压级校准中只能给出了传声器的电学特性的特点本文初步描述了使用该方法的激波管系统的组成,实验步骤以及ＨＣ１６传声器初步实验的结果。”     

Hydrogen/carbon monoxide syngas burning rates measurements in high-pressure quiescent and turbulent environment

A high-pressure, double-chamber, fan-stirred, large-scale explosion facility is proposed for measurements of laminar and turbulent burning velocities, S_L and S_T, of centrally-ignited hydrogen and carbon monoxide syngas/air mixtures over an initial pressure range of p = 0.1-1.0 MPa. Results show that lean syngas laminar flames at elevated pressure are highly unstable resulting in cellular structures all over the expanding flame front surface, where S_L∼p^−0.15 having a relatively modest decrease with pressure as compared to lean methane flames where S_L∼p^−0.50. Contrarily, as to lean syngas turbulent flames, values of S_T increase with increasing pressure (S_T∼p^0.15) at a fixed r.m.s. turbulent fluctuating velocity (u′ ≈ 1.4 m/s). Moreover, it is also shown that increasing u′/S_L is still a way much more effective in increasing values of S_T/S_L than increasing pressure. Finally, discussions are offered and area for further studies identified.     

Features of a double-chamber bed and case study

A double-chamber bed (DCB) was developed in China in 1980 and has been used for more than 500 sets. This paper introduces the structural and operational features of DCB and concludes that their unique structure leads to perfect operational features; thus, it is the best option for reconstruction projects and can replace other types of ion-exchangers such as mixed-beds, double-cell fluidized beds, multi-beds, etc. Then, four reconstruction project cases were introduced that were selected from more than 20 plants designed by us. From the case study it can be concluded that DCBs can be used not only to treat different source waters (river and well) but can also be used to treat water with a ratio of transient hardness to total cations to be less than 0.5 with the ratio of strong to weak anions to be more than 7.0. These findings enlarge the application scope of DCBs.