地下矿主水平铁路运输与汽车运输孰优

介绍地下运输设备的新发展, 包括载重１２０ｔ的Ｍａｍｍｏｔｈ汽车，Ｋｉｒｕｎａ电动汽车，Ｉｎｃｏ自动运输汽车，Ｌｅｗｉｎ多点驱动带式输送机等。作者对铁路，汽车和胶带运输的特点和应用范围作了述评，认为这三种主要运输方式各有所长，制造厂家和用户正在创造性地把他们的优点结合起来，努力开发各种新产品，潜力很大。     

现代破碎设备的结构和参数

当前,随着能源的短缺和费用的高涨,现代矿山碎磨设备正面临着亟待研究解决的重要课题,就是改进现有碎磨设备的结构性能和工作参数,急需研制新型的高效率、能耗低的碎磨设备,来提高这种设备的能源效率、粉碎效率和生产能力,以降低碎磨设备的单位能耗、     

In situ particle size measurements using a two-color laser scattering technique

We have developed a technique using light scattered from individual particles in the near-forward direction to measure particle size in the range of 10-200 microm. This technique uses the Mie scattering theory to relate the measured light intensity to particle size based on calibration techniques employing pinholes and water droplets of known size. We have applied a unique two-color optical arrangement to minimize the edge effect which can cause incorrect size measurements for particles that pass through the edge of the laser beam focal volume. In this paper we describe our experimental technique and the results of size measurements obtained with this technique for water droplets and pulverized coal particles.     

Robustness of an aerobic metabolically vinyl chloride degrading bacterial enrichment culture

Degradation of the lower chlorinated ethenes is crucial to the application of natural attenuation or in situ bioremediation on chlorinated ethene contaminated sites. Recently, within mixtures of several chloroethenes as they can occur in contaminated groundwater inhibiting effects on aerobic chloroethene degradation have been shown. The current study demonstrated that metabolic vinyl chloride (VC) degradation by an enrichment culture originating from groundwater was not affected by an equimolar concentration (50 μM) of cis-1,2-dichloroethene (cDCE). Only cDCE concentrations at a ratio of 2.4:1 (initial cDCE to VC concentration) caused minor inhibition of VC degradation. Furthermore, the degradation of VC was not affected by the presence of trans-1,2-dichloroethene (tDCE), 1,1-dichloroethene (1,1-DCE), trichloroethene (TCE), and tetrachloroethene (PCE) in equimolar concentrations (50 μM). Only cDCE and tDCE were cometabolically degraded in small amounts. The VC-degrading culture demonstrated a broad pH tolerance from 5 to 9 with an optimum between 6 and 7. Results also showed that the culture could degrade VC concentrations up to 1,800 μM (110 mg/L).     

A laboratory assessment of the impact of brewery wastewater discharge on sulfide and methane production in a sewer

The impact of brewery wastewater discharge on sulfide and methane production in a sewer was assessed. Experiments were carried out on laboratory scale sewer reactors consisting of both an experimental and a control reactor. The control reactor was intermittently fed with real fresh sewage while the experimental reactor was fed with a mixture of brewery and domestic wastewater at two different proportions (10 and 25% v/v). 10% v/v discharge of brewery wastewater increased the H2S and CH4 production rates in the sewer reactor by 40% and 30%, respectively. When the brewery wastewater fraction was increased to 25% v/v, the H2S production rate of the experimental reactor decreased to the level of the control reactor. In contrast, the CH4 production rate maintained at a level that was 30% higher than that in the control reactor. These results indicate that the discharge of brewery wastewater into sewers can give negative impacts in relation to odour and corrosion management of the systems and will increase the greenhouse gas emissions from sewers. The study also reveals that the impact of trade waste on the biological reactions in sewers is complex, and requires careful experimental assessment in each case.     

Planar laser-induced-fluorescence imaging measurements of OH and hydrocarbon fuel fragments in high-pressure spray-flame combustion

Planar laser-induced fluorescence images of OH have been obtained in liquid-fueled spray flames burning heptane, ethanol, and methanol over a range of pressures from 0.1 to 1.0 MPa. In addition to the OH fluorescence, a nonresonant fluorescence interference that increased rapidly with pressure was detected. Examination of the spectrum of this interference indicates that it arises from hydrocarbon fuel-fragment species in the fuel-rich zones of the flame. The pressure dependence of the fluorescence signal is examined in both steady-state and time-dependent analyses, and a model for evaluation of pressure effects and quenching variations in quantitative imaging measurements in nonpremixed flame environments is presented. The results indicate that increased combustor pressure results in a rapid rise of the volume fraction of hydrocarbon fragments and a decrease in the OH volume fraction.     

Effective visualization of complex vascular structures using a non-parametric vessel detection method

The effective visualization of vascular structures is critical for diagnosis, surgical planning as well as treatment evaluation. In recent work, we have developed an algorithm for vessel detection that examines the intensity profile around each voxel in an angiographic image and determines the likelihood that any given voxel belongs to a vessel; we term this the "vesselness coefficient" of the voxel. Our results show that our algorithm works particularly well for visualizing branch points in vessels. Compared to standard Hessian based techniques, which are fine-tuned to identify long cylindrical structures, our technique identifies branches and connections with other vessels. Using our computed vesselness coefficient, we explore a set of techniques for visualizing vasculature. Visualizing vessels is particularly challenging because not only is their position in space important for clinicians but it is also important to be able to resolve their spatial relationship. We applied visualization techniques that provide shape cues as well as depth cues to allow the viewer to differentiate between vessels that are closer from those that are farther. We use our computed vesselness coefficient to effectively visualize vasculature in both clinical neurovascular x-ray computed tomography based angiography images, as well as images from three different animal studies. We conducted a formal user evaluation of our visualization techniques with the help of radiologists, surgeons, and other expert users. Results indicate that experts preferred distance color blending and tone shading for conveying depth over standard visualization techniques.