Discharge Measurement Using Portable Dilution Gauging Flowmeters

This paper suggests that the relative salt (sodium chloride) dilution method should be more widely used for the routine measurement of stream discharge, and has been written to increase awareness of the technique among flow-gauging practitioners. Recent improvements in instrumentation have increased accuracy and simplified practical application, making the method better suited (in many circumstances) than the more widely used alternatives. The paper (a) reports on a field study to evaluate the performance of a portable dilution-gauging flowmeter, and (b) considers the environmental issues which are associated with the method. The review reveals that the use of salt (in the quantities typically required) is unlikely to have any significant ecological impact, and argues that environmental concerns are founded upon little scientific basis.     

Pulse-Tube Dilution Refrigeration below 10 mK for Astrophysics

Astroparticle bolometric detectors often rely on the use of dilution refrigerators providing a large cooling power at millikelvin temperatures. Conventional machines, however, need a systematic supply of cryogenic fluids, complicating and making more expensive their operation, particularly in underground laboratories. We describe here novel cryogen-free dilution units, able to cool down large detectors to millikelvin temperatures, and where cooling and warming times have been optimised.      

基于GDOP的分布式雷达网航迹关联阈值选择新方法

分布式雷达组网的航迹关联不仅与网内各雷达的性能有关,而且与目标的相对位置有关。本文提出一种新的雷达组网航迹关联方法,该方法在综合网内各雷达性能的基础上,将组网雷达定位精度几何稀释模型引入航迹关联算法当中。根据各雷达对观测同一目标定位精度的差异为参考,给出一种新的航迹关联门限阈值选择算法。本文介绍了航迹关联阈值的计算过程,并利用该方法对真实航迹数据进行了仿真。     

乙烯装置稀释蒸汽发生系统存在的问题及解决措施

对大庆石化分公司化工一厂裂解老区乙烯装置稀释蒸汽系统存在的稀释蒸汽发生量低、急冷水排放量大及COD高等问题进行了介绍,通过采取改进措施解决了这些问题,同时达到了节能减排的目的。     

Mechanical Stress on Lysozyme Crystals during Dynamic Cross‐Flow Filtration

The influence of mechanical stress on the crystal size distribution of lysozyme crystal slurries in a dynamic cross‐flow device is discussed. The reduction of crystal size may have an influence on mass and resistance of the fouling layer. A filter test device with a filter area of 130 cm² is used for thickening. After thickening, a model impurity, namely bovine serum albumin, is washed out of the suspension. A reduction of crystal size due to stirring and a reduced fouling layer with increasing stirrer speed is observed. Furthermore, a higher stirring speed increases the specific filtrate flux. In the presence of the impurity, more crystal aggregates than single isometric crystals are formed and, hence, the decrease of crystal size due to shear forces is more pronounced than without impurity.     

Experimental investigation of the effects of separate hydrogen and nitrogen addition on the emissions and combustion of a diesel engine

An experimental investigation of the effects of separate hydrogen and nitrogen addition on the emissions and combustion of a diesel engine was performed and the results are presented in the current paper.     

Effects of dilution ratio and seed layer on the crystallinity of microcrystalline silicon thin films deposited by hot-wire chemical vapor deposition

We deposited microcrystalline silicon (μc-Si) by hot-wire chemical vapor deposition (HWCVD) at different thickness and dilution ratio, with and without seed layer. As the dilution ratio increased, we observed an increase in the amount of microcrystalline phase in the film, a change in the structure of the grains and a loss of the (220) preferential orientation. The films deposited over a seed layer had a larger fraction of crystalline phase than films deposited with the same parameters but without a seed layer. For high dilution ratios (R=100), most of the film grows epitaxially at the interface with the Si substrate, but a microcrystalline film slowly replaces the single-crystal phase. For low dilution ratios (R=14), the film starts growing mostly amorphously, but the amount of crystalline phase increases with thickness.     

有底柱分段崩落法在生产应用中的若干改进

针对倾斜中厚矿体应用有底柱分段崩落法出现矿石贫化损失指标较大的问题，进行了室内放矿试验，将试验指标与生产指标对比分析之后，提出了若干改进采矿工艺结构参数的措施。     

有底柱阶段崩落法的两步骤放矿研究

通过对有底柱阶段崩落法５种放矿方案的分析研究，提出能改善现场放矿指标的两步骤放矿的放矿方案。该方案工艺简单，操作性强，管理方便，已在弓长岭井下铁矿的生产实践中得到应用。取得较好的效果。     

Group aggregating normalization method for the preprocessing of NMR-based metabolomic data

Data normalization plays a crucial role in metabolomics to take into account the inevitable variation in sample concentration and the efficiency of sample preparation procedure. The conventional methods such as constant sum normalization (CSN) and probabilistic quotient normalization (PQN) are widely used, but both methods have their own shortcomings. In the current study, a new data normalization method called group aggregating normalization (GAN) is proposed, by which the samples were normalized so that they aggregate close to their group centers in a principal component analysis (PCA) subspace. This is in contrast with CSN and PQN which rely on a constant reference for all samples. The evaluation of GAN method using both simulated and experimental metabolomic data demonstrated that GAN produces more robust model in the subsequent multivariate data analysis, more superior than both CSN and PQN methods. The current study also demonstrated that some of the differential metabolites identified using the CSN or PQN method could be false positives due to improper data normalization.