摘要：LCO_2(liquid CO_2) can absorb heat and release latent heat via phase transition, which can provide considerable cooling energy and effectively solve the problem of thermal damage in deep coal mining processes. A LCO_2 cycle refrigeration system is designed to continuously cool down the working face in a mine, and CO_2 is cyclically utilized. Additionally, LCO_2 is used not only as a cold source but also to prevent spontaneous combustion of coal in the gob. COMSOL Multiphysics simulation software is used to characterize the thermal performance of the heat exchange system, where the heat transfers between the CO_2 and the airflow. For a LCO_2 consumption of 13.54 m^3/h, the temperature of the airflow in the tunnel decreases by 7.72°C, and the cooling volume of the system reaches 142.99 kW/h; the cooling volume provides a latent heat release of 46.68 k W/h. The main influencing factors of the refrigeration system, such as ventilation flux, LCO_2 flow, LCO_2 temperature and initial tunnel temperature, are also analyzed quantitatively through the software. The temperature of the steady airflow in the tunnel is proportional to the square of the local fan ventilation flux, and it decreases linearly with an increase in the LCO_2 flow but increases with both the temperature of the LCO_2 and the initial temperature in the tunnel. When the temperature difference between the LCO_2 and wind increases, the heat exchange between the CO_2 and wind intensifies, and the cooling volume increases.

摘要：Thermoelectric effect is the most efficient way to convert electric energy directly from the temperature gradient. Thermoelectric effect-based power generation, cooling and heating devices are solid-stated, environmentally friendly, reliable, long-lived, easily maintainable, and easy to achieve miniaturization and integration. So they have unparalleled advantages in the aerospace, vehicle industry, waste heat recovery, electronic cooling, etc. This paper reviews the progress in thermodynamic analyses and optimizations for single- and multiple-element, single- and multiple-stage, and combined thermoelectric generators, thermoelectric refrigerators and thermoelectric heat pumps, especially in the aspects of non-equilibrium thermodynamics and finite time thermodynamics. It also discusses the developing trends of thermoelectric devices, such as the heat sources of thermoelectric generators, multi-stage thermoelectric devices, combined thermoelectric devices, and heat transfer enhancement of thermoelectric devices.

摘要：This article is in view of the existing water dispensers’ repeated heating, large energy consumption and fresh water quality’s problem, designed a new type energy saving water dispenser with the function of rapid cooling-or-heating. Anhydrous bravery structure is used in the water dispensers in drinking water flow process to cool or heat it, so as to ensure the water quality fresh. Among them, the application of semiconductor refrigeration technology achieved collecting heat and preheating the water [1], which is called the initial heating. Cooperating with the secondary heating of the electrothermal quartz heating tube, the water dispensers really realize the flowing liquid heating, bid farewell to the so-called thousand-times boiling water and improve the heat energy utilization greatly [2].

摘要：掌握现代科学技术提高装帧艺术水平王肖生现代电脑的产生和发展，为编辑、美术设计人员提供了现代化的、先进的编辑加工、绘画创作及排版的手段。通过电脑，利用绘画专用的计算机软件，可以进行美术作品的创作和封面装帧设计。适合于绘画、装帧设计的计算机系统的硬件主要...

摘要：最近，位于英国King’s Lynn的商用冷柜制造商Foster refrigeration发布已经将SolidWorks软件应用于所有新的产品设计中，例如披萨面团冷藏柜。Foster公司透露，因为3DCAD软件和Cosmos软件可以在屏幕上显示三维样机设计和部件分析的过程，而PDMWorks软件则可允许多个设计师同时进行同一个设计。因此，成功地将其产品开发周期缩短到原先的一半，并将样机成本减少了三分之一。