Case Study: Intermediate Field Mixing for a Bank Discharge in a Natural River

The intermediate field mixing characteristics of the Gold Bar Wastewater Treatment Plant effluent into the North Saskatchewan River at Edmonton were evaluated. This region may be considered to be the early part of the transverse mixing region where local channel characteristics are important. An extensive field study was conducted to delineate the bathymetry of the study area and evaluate the mixing characteristics by means of a steady state dye test. The topographic and limited velocity results of the field study were used to create and validate a depth-averaged hydrodynamic model of the study reach in order to extract streamtube information. The results from the hydrodynamic model were used to interpret the mixing characteristics of the study reach as well as extract channel characteristics. From the analysis it is evident that the distribution of effective transverse mixing coefficient is highly dependent on local river conditions. The use of the hydrodynamic model to extract channel characteristics provided a reasonable estimate of mixing characteristics without requiring detailed field velocity data. The trade-off is more detailed bathymetry data is required to have a realistic model. Plume averaged channel characteristics rather than cross sectional averaged were shown to produce more realistic transverse mixing coefficients. Assumed Gaussian profile distributions were successfully applied suggesting that for a bank discharge if the maximum bank concentration and mass flux are known this technique could be applied.     

一种天线阵列定位法及其仿真研究

为了克服CDMA移动台(MS)定位估计中面临的远近效应问题,该文提出了一种在服务基站(BS)附近布置一种天线阵列,采用TSOA/AOA混合定位技术对MS进行定位估计的方法,分析了采用不同定位法的GDOP分布, 并给出了相应的TSOA/AOA混合定位算法。不同条件下的仿真结果表明,只要AOA测量值达到一定精度,采用这种方法就能对MS进行准确定位。     

橄榄的抑菌效应及其药效成分的初步研究

采用MTT法和培养权连续稀释法研究了橄榄对几种常见细菌、霉菌和酵母菌的抑制效应,并对其药效成分进行了初步鉴定。结果表明,橄榄对所试菌株有较为明显的抑制作用。黄酮类物质及没食子酸可能是其抑菌防腐的主要药效成分。     

LASER 300S在线激光打孔参数的选择

通过对PROTOS1-8高速卷烟机在线激光打孔参数的组合试验和数据回归分析,得出了烟支稀释率与脉冲、脉冲与能量的乘积、能量、打孔数量等参数的线性相关方程。试验结果表明,利用各线性方程可计算出能保证LASER 300S激光打孔系统正常运行的参数组合,与实际在线打孔的烟支稀释率值具有较好的符合性和稳定性,能够提高在线加工质量。     

Dilution effects analysis on NOx emissions of opposed-jet H2/CO syngas diffusion flames

Syngas is a promising alternative fuel for stationary power generation due to cleaner combustion than convectional fossil fuels. During the gasification processes, the by-products of CO₂, H₂O, or N₂ may be present in the syngas mixture to control the flame temperature and emissions. Several studies indicated that syngas with dilutions is capable of reducing pollutant emissions such as NO_x emissions. This work applied a numerical model of opposed-jet diffusion fames to explore the dilution effects on NO_x formation and differentiate the inert effect, thermal/diffusion effect, chemical effect, and radiation effect from CO₂, H₂O, or N₂ dilutions. The numerical study was performed by a revised OPPDIF program coupling with narrowband radiation model and detail chemical mechanism. The dilution effects on NO_x formation were analyzed by comparing the realistic and hypothetical cases. Regardless the diluent types, the inert effect is the main cause to reduce NO production, followed by chemical effect and radiation effect. The thermal/diffusion effect may promote NO formation because the preferential diffusion due to different diffusivities between diluents and syngas magnifies the reaction rate locally. CO₂ dilution reduces NO by radiation effect at low strain rate, and contributes NO reduction by chemical effect at high strain rate. At the same dilution percentage, CO₂ dilution reduces NO production the most, followed by H₂O and N₂. Besides the thermal/diffusion effect, the chemical effect of H₂O enhances NO production through thermal route and reburn route.     

高进路低采高采矿法对降低贫化率的意义

本文介绍了在缓倾斜薄矿层中应用高进路低采高采矿法的基本情况,并对其基本特点、构成要素、回采工艺等进行了探索。通过有效控制采高,使贫化率降低到10％—15％。     

同位素稀释质谱法测定反应堆辐照元件样品中^149Sm和^150Sm含量

本文描述用同位素稀释质谱法测定反应堆辐照元件中~(149)Sm和~(150)Sm含量的方法步骤,研究了~(149)Sm、~(150)Sm沿反应堆元件的轴向分布规律。     

我国铝土矿资源开采技术综述

调查表明,目前国内铝土矿85%以上为露天开采,其余为地下开采和民采。露天开采主要针对沉积型和堆积型铝土矿;地下开采主要针对二迭纪铝土矿山、中上石炭纪铝土矿山和中石炭纪铝土矿山。存在问题主要是:资源的综合回收率低;矿山开采规模较小,效率低下;地下铝土矿开采技术不成熟;矿山采矿用地及复垦成本高,复垦土地机制不完善。     

X—52~#活性环氧树脂稀释剂的合成及性能研究

活性环氧树脂稀释剂x—52~#是一种原料易得、成本低、毒性小,质量稳定、性能优越的新品种。本文详述了该稀释剂的合成方法,文章涉及原料选择,工艺确定,实验室小试、中试,工业生产,产品性能特点及其应用研究等。     

Refolding of lysozyme at high concentration in batch and fedbatch operation

Based on optimization of denaturing conditions and the character of time course of protein refolding, renaturation by dilution in batch and fed-batch operation to improve yield as well as the initial and final protein concentrations has been studied. The optimum DTT in denatured solution was 30 mM. Urea can suppress protein aggregation to sustain pathway of correct refolding at high protein concentration. Fed-batch operation was better than batch dilution with comparison of yield recovery in large-scale downstream processes. Under our research condition in fed-batch operation, lysozyme was successfully refolded from initial protein concentration of up to 40 mg/mL by dilution 20-fold, the yield recovery was nearly 60%.