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31.
本文阐述了充分考虑矿石性质,探索出混合浮选的分步流程,恰当的施用多元扑收剂所产出的“协同效应”,稳定和强化选别工艺,收到提高选金技术指标的效果。 相似文献
32.
纯电动汽车车载动力电池是其唯一的动力源且很有限,辅助设备消耗的电能减少了纯电动汽车的续驶里程,尤其是空调,所以开发高效的纯电动汽车空调系统是纯电动汽车能够被市场接受的关键。将纯电动汽车顶盖布满太阳电池,可以使空调系统的制冷能力增强,同时还能增加纯电动汽车的行驶距离。对小型纯电动汽车的太阳能辅助空调系统进行研究,设计出适合该空调的自动控制系统,可为纯电动汽车创造出一个更加舒适的驾驶和乘座环境。 相似文献
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对于固定安装的光伏电池板,其倾角的选择直接影响到所接收到的太阳辐射量,从而决定着太阳能利用系统的性能。本文在获得南京地区辐射资料的基础上,采用太阳辐射量气象学模型,针对任意方位角固定式安装的光伏电池板给出了最佳倾角的计算结果。该结果可为南京地区太阳能系统的设计与安装提供理论依据,并为相近地区太阳辐射量计算提供参考。 相似文献
35.
An emitting, absorbing, and anisotropically scattering plain medium containing a suspension of ZnO particles is considered, in which the particles are directly exposed to high-flux irradiation and undergo shrinkage during their endothermic dissociation into Zn(g) and O2 at above 2100 K. The unsteady energy equation that links the rate of radiative heat transfer to the rate of the chemical reaction is formulated and solved numerically by the finite volume technique and the explicit Euler time-integration scheme. The path-length Monte Carlo method is applied for modeling the radiative transfer within the suspension using the absorption/scattering coefficients and the scattering phase function obtained from the Mie theory. It is found that the particle suspension can be heated rapidly from its initial 300 K to over 1800 K in less than 0.1 s, resulting in a more uniform temperature profile as the reaction progresses, particles shrink, and the suspension becomes optically thinner. The chemical conversion increases with decreasing initial particle diameter and volume fraction due to the efficient radiative absorption. 相似文献
36.
This paper presents a new maritime lifesaving multiple-effect solar still design where several extended wicks feed seawater to their evaporating areas by capillary force, and the resulting water vapor diffuses and condenses on facing wicks with the condensate flowing through the wicks into storage bags. A theoretical analysis showed that a temperature drop through diffusion layers between evaporating and condensing wicks slowly increases in the main evaporating areas and rapidly near salt depositions whereas the evaporation rate decreases slowly in the main area and rapidly near salt depositions. These changes are caused by increases in salt concentrations and resulting boiling point elevation. With steady-state transfer analysis, the proposed still is predicted to produce about 15 kg m −2d−1 fresh water on a sunny day of 22 MJm−2d−1 solar radiation, showing a potential to be a maritime lifesaving desalinator. 相似文献
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Jae-Wook Lee Kyung-June Hwang Wang-Geun Shim Kyung-Hee Park Hal-Bon Gu Kyu-Hyuk Kwun 《Korean Journal of Chemical Engineering》2007,24(5):847-850
Dye sensitized solar cells (DSSCs) have been receiving significant attention because they have many advantages compared to
conventional organic solar cells. It has been known that the photovoltaic characteristics of DSSC are highly dependent on
the adsorption properties of dyes on TiO2 films. To analyze the surface heterogeneity of TiO2 surfaces, single-phase anatase nanocrystallite titanium films were prepared by sol-gel method using the hydrolysis reaction
of titanium tetraisopropoxide under acidic condition and characterized by XRD, FE-SEM and BET analysis. The adsorption energy
distribution functions were calculated by the generalized nonlinear regularization method. It was found that the shape and
the intensity of the adsorption energy distribution curve determined were highly related with the physical properties (i.e.,
geometrical heterogeneity) and chemical characteristics (i.e., energetic heterogeneity) of nanocrystalline TiO2 for DSSC. 相似文献
39.
Lourdes García-Rodríguez Ana I. Palmero-MarreroCarlos Gómez-Camacho 《Desalination》2002,142(2):135-142
This paper deals with a global analysis of the use of solar energy in seawater distillation under Spanish climatic conditions. Static solar technologies as well as one-axis sun tracking were compared. Different temperature ranges of the thermal energy supply required for a desalination process were considered. At each temperature range, suitable solar collectors were compared in some aspects as: (1) fresh water production from a given desalination plant; (2) attainable fresh water production if a heat pump is coupled to the solar desalination system; (3) area of solar collector required for equivalent energy production. Results showed that direct steam generation (DSG) parabolic troughs are a promising technology for solar-assisted seawater desalination. 相似文献
40.