气体含液浓度对亲油型聚结滤芯压降及含液量的影响

针对天然气输送管路中气体含液浓度变化范围宽且严重影响滤芯正常使用的问题,为了分析气体含液浓度对滤芯压降和含液量的影响,以及研究不同层数滤芯应用于不同浓度工况下的可行性,利用滤芯过滤性能评价装置比较了0.07~1.00 g×m^(-3)不同气体含液浓度条件下不同层数滤芯的压降变化。结果表明:气体含液浓度通过改变滤材内运移液体的通道数目而对滤芯通道压降产生较大影响,浓度升高导致通道数目增多、通道形成时间缩短、滤芯各层含液量增多。同时发现,通道压降随气体含液浓度的增大呈非线性增长,其中气体含液浓度影响的滤材含液量是否达到饱和值,是通道压降急剧上升的关键。此外,滤芯层数通过影响通道数目而改变通道压降增长趋势,当气体含液浓度在0.2~0.4 g×m^(-3)时,增加滤芯层数,可以降低通道压降。建立的气体含液浓度、滤芯层数与通道压降的关系模型可为工程实际中滤芯结构优化和不同浓度工况下通道压降预测提供指导帮助。

旋风过滤装置天然气脱水试验研究

旋风过滤装置在气液分离领域有着广泛的应用。为此设计一种新型的旋风过滤分离装置,该装置具有分离效率高,设备适应性强,清洁环保、操作稳定等传统天然气脱水设备不具备的优点。试验中对不同的含液浓度和入口气速对分离效率和溢流压降的影响进行了研究及分析。试验结果显示:随着气速的增加分离效率会出现不同幅度的下降而可以反映能耗的溢流压降在不断上升;含液浓度的变化对溢流压降没有明显的影响,而含液浓度的提高可以在不同程度上提高分离效率。通过实验结果可以分析得出旋风过滤装置在入口气速8~10 m/s且含液浓度在20~25 g/m^3的情况下具有较好的分离性能。

Evaluating the performance of a WRF microphysics ensemble through comparisons with aircraft observations

observation data obtained in a mesoscale convective system are compared to Weather Research and Forecasting(WRF)model simulations using four microphysics schemes(Morrison,WSM6,P3,SBM)with different complexities.The main purpose of this paper is to assess the performance of the microphysics ensemble in terms of cloud microphysical properties.Results show that although the vertical distributions of liquid water content(LWC)and ice water content(IWC)simulated by the four members are quite different in the convective cloud region,they are relatively uniform in the stratiform cloud region.Overall,the results of the Morrison scheme are very similar to the ensemble average,and both of them are closer to the observations compared to the other schemes.Besides,the authors also note that all members still overpredict the LWC by a factor of 2–8 in some regions,resulting in large deviation between the observation and ensemble average.

Comparison of aircraft observations with ensemble forecast model results in terms of the microphysical characteristics of stratiform precipitation

The prediction of the particle number concentration and liquid/ice water content of cloud is significant for many aspects of atmospheric science.However,given the uncertainties in the initial and boundary conditions and imperfections of microphysical schemes,the accurate prediction of these microphysical properties of cloud is still a big challenge.The ensemble approach may be a viable way to reduce forecast uncertainties.In this paper,a large-scale stratiform cloud precipitation process is studied by comparing results of a 10-member ensemble forecast model with aircraft observation data.By means of the ensemble average,the prediction of bulk parameters such as liquid water content and ice water content can be improved in comparison with the control member,but the particle number concentrations are still one to two orders of magnitude less than those from observations.Intercomparison of raindrop size spectra reveals a big distinction between observations and predictions for particles with a diameter less than 1000μm.

Alkaloid Accumulation in Catharanthus roseus Increases with Addition of Seawater Salts to the Nutrient Solution

A sand culture experiment was conducted to determine the effects of different seawater (5% and 10%) treatments on plant growth,inorganic ions,indole alkaloid concentrations and yields of Catharanthus roseus,in an effort to increase the alkaloid yield by artificial cultivation.The total fresh and dry weights and tissue K + concentrations decreased,but Na + concentrations increased in the plant roots,stems and leaves of C.roseus under seawater stress as compared to the control.The concentrations and yields of vindoline,catharanthine,vinblastine and vincristine increased under seawater stress.The concentrations and yields of these alkaloids were higher in 5% seawater-treated plants than those in the 10% seawater-treated plants.Considering the industrial production,5% seawater treatments could reduce the cost of producing alkaloid.In the control plants,the highest alkaloid concentrations reached a peak at 100 days after planting,suggesting that plant harvest must be optimized in terms of growth duration.