Numerical simulation on the behavior of a liquid jet into an air flow

A numerical simulation has been performed to clarify the effects of turbulence in a liquid on the deformation of the liquid jet surface into an air flow. The turbulences in the liquid jet were simulated by the Rankin vortices, and the liquid jet surface was tracked numerically by the volume of fluid method. By numerical simulations, the onset of the protrusions on the liquid jet surface is caused by the vortices in the liquid, and the surrounding air flow plays an important role in the amplification of the protrusions. The amplification rate of the trough displacement is proportional to the air‐to‐liquid velocity ratio. At large imposed vortex intensities, the trough displacement increases with the vortex intensity. On the other hand, at small imposed vortex intensities, the amplification of the trough displacement is also affected by factors other than vortex intensity. © 2001 Scripta Technica, Heat Trans Asian Res, 30(6): 473–484, 2001     

深部巷道围岩分区破裂现象的试验与现场监测对比分析研究

为了从本质上认识一些深部巷道中出现的围岩破裂区和完整区间隔排列的分区破裂现象。以淮南矿区丁集煤矿深部巷道工程为研究对象进行了模型试验研究。并通过对现场监测结果和模型试验结果的对比研究与相互验证,归纳分析出了分区破裂现象的主要特征和变化规律,指出分区破裂是与洞室呈同心圆的环状拉破坏断裂。研究结果对于认识深部洞室围岩的破坏方式,揭示深部洞室围岩的变形破坏机理具有重要意义。     

Electrical blasting disintegration of copper-nickel ores conjointly with separation of particles by size

Absract The effect of electrical blast parameters is studied for grinding mineral materials by example of copper-nickel ore. It is shown that the average energy consumed by the electrical blasting is within 5–50 J/g. The particle disintegration mechanism has been considered at high and low electric conductivity of ore. It is established that grinding and separation of particles by size are possible to be performed conjointly in the same apparatus. __________ Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 1, pp. 100–107, January–February, 2007.     

紫金山铜金矿黄铁矿环带结构特征

主要通过对紫金山铜金矿成矿期环带状黄铁矿的特征研究,来探讨成矿期地质环境及成矿作用。利用电子探针对不同深度矿化带中具环带结构黄铁矿的内核和环带中的微区进行化学成分分析,发现环带黄铁矿属于亏铁富硫型。Ni-Co(-As)图解显示环带状黄铁矿为火山—热液成因;环带是主要载金部位,金以纳米级自然金颗粒形式存在。结合本矿矿区地质、矿相学、岩石地球化学特征,认为本矿成矿期环带黄铁矿的形成与本区燕山晚期的火山—岩浆侵入活动密切相关,体现紫金山铜金矿的成矿流体是燕山晚期富含Cu、Au、Pb、Zn等成矿元素的火山热液叠加在燕山早期具有W、Sn、Mo、Bi等矿化的紫金山复式花岗岩岩体上。     

Electrical disintegration and micro-focus X-ray CT observations of cement paste samples with dispersed mineral particles

Electrical disintegration is an effective liberation technique in mineral processing where the liberation ratio depends on the mineralogical properties of the mineral grains. However elucidation of the liberation behavior is difficult since the fragments after the electrical disintegration are fine and complex. This study applies electrical disintegration to cement paste samples with various dispersed mineral particles (calcite, quartz, albite, and pyrite) and the disintegrated products are observed with a micro-focus X-ray CT scanner. Current channels and crack extension behavior from the channels are identified by cross sectional CT and three dimensional reconstructed images. A classification of the crack patterns was carried out and compared with the results of liberation ratio measurements of the products.     

Combined bioreaction and separation in centrifugal fields using zonal rotors

Combined biosynthesis and product separation has been successfully performed for the first time using a zonal centrifugal bioreactor–separator. The biosynthesis of dextran polymer from sucrose using the dextransucrase enzyme was investigated in order to evaluate bioreactor performance. The bioreactor consisted of a bowl, fitted with a Reorienting gradient rotor which facilitated substrate and enzyme loading and the reproducible unloading of solutions from the system. This allowed the distribution of substrate, enzyme and product materials in the bowl at the end of each trial to be accurately determined. Studies have indicated that combined bioreaction–separation is possible using this system. However, viscosity build-up in the bioreactor must be minimised in order to increase the yield of polymer product per unit time and improve product separation.     

Understanding variability in winegrape production systems 2. Within vineyard variation in quality over several vintages

Spatial variability in various indices of winegrape quality was studied over several vintages in blocks planted to Cabernet Sauvignon and Ruby Cabernet in the Coonawarra (1999–2002) and Sunraysia (2000–2002) regions of Australia. At both sites, inter‐annual variation was marked whilst intra‐annual variation was much greater for some indices (e.g. concentration of total phenolics) than others (e.g. Baumé). The magnitude of intra‐annual variation was readily identified in terms of the ‘spread’, defined as the difference between the maximum and minimum values, expressed as a % of the median value. Typical values of the spread were 20% for Baumé, but could be as high as 117% for phenolics, and better indicated the extent of variation facing the winemaker than the coefficient of variation (CV; typically 3% for Baumé and 14% for phenolics). For all attributes, variation in any given year showed marked spatial structure, with the patterns of variation being broadly consistent for each attribute in each year of the study, and with many attributes following similar patterns. The results therefore strongly support the idea of zonal vineyard management. However, fruit quality zone identification is dependent on a large sampling effort. Therefore, given the current availability of yield monitors, the finding that between‐zone differences in quality indices were generally significant (P < 0.05) for zones identified on the basis of yield alone, and, in the absence of an on‐the‐go sensing capability, it is suggested that zonal management should proceed on the basis of zones of characteristic yield productivity. Based on the present work, it is suggested that development of an on‐the‐go fruit quality sensing technology would enable the wine industry to maximise its opportunity to gain benefit from differential vineyard management such as selective harvesting. Indeed, the results of this work suggest that in the absence of zonal management, preferably supported by on‐the‐go quality sensing, winemaker demands for delivery of uniform parcels of fruit are unlikely to be satisfied.     

运力限制下区间车与全程车的组合调度模型

针对单条线路双向及单向客流分布的不均衡性, 并考虑实际运营中的运力限制条件, 建立了基于社会总体效益最优为目标、对区间车和双向全程车的发车频率及区间车折返位置同时进行优化的组合调度模型.通过一个算例进行验证, 探讨了在给定运力下组合调度最优发车频率、折返点位置和成本的关系, 并与优化的单一调度进行对比, 结果表明:在客流分布不均衡和运力限制的情况下, 组合调度比单一调度能有效减少系统成本和乘客平均出行时间, 运力限制越强, 组合调度带来的效益更加明显, 运力限制下可以通过组合策略减少系统成本, 且存在系统总成本最低的最佳运力配置.     

新疆哈图金矿地质地球化学特征及其成矿作用

哈图金矿产于和持定的地质地球化学背景上，受断裂构造及中酸性侵和岩控制，各时代地层及其组成岩石的金元素及相关元素含量低（金元素的浓集系数小于０．８），中酸性侵入岩金元素丰度值较高，断裂构造中金元素的含量最高，岩体－断裂－矿体三者是地质成矿作用的统一体，矿体中成矿元素具有垂直分带性。矿体的延深有大于延长的趋势，哈图金矿属岩浆期后中温热液矿床。     

燃煤分体相变加热装置在油气集输领域的可行性分析

节约和替代燃料油是解决我国石油资源短缺,缓解石油供需矛盾,增强企业竞争力的措施之一。在油气集输领域,以煤作燃料代替燃料油可以有效地降低生产成本,节约油气资源,实现企业节能降耗的目的。文章较详细地介绍了一种燃煤分体相变加热装置的工作原理、结构特点、性能特点,从它的结构特点和性能特点上看,该装置在油气集输领域作为加热装置是可行的,且能缓解上述矛盾。