Mechanochemical leaching of chalcopyrite concentrate by sulfuric acid

This study aimed to introduce a new cost-effective methodology for increasing the leaching efficiency of chalcopyrite concentrates at ambient temperature and pressure. Mechanical activation was employed during the leaching (mechanochemical leaching) of chalcopyrite concentrates in a sulfuric acid medium at room temperature and atmospheric pressure. High energy ball milling process was used during the leaching to provide the mechanochemical leaching condition, and atomic absorption spectroscopy and cyclic voltammetry were used to determine the leaching behavior of chalcopyrite. Moreover, X-ray diffraction and scanning electron microscopy were used to characterize the chalcopyrite powder before and after leaching. The results demonstrated that mechanochemical leaching was effective; the extraction of copper increased significantly and continuously. Although the leaching efficiency of chalcopyrite was very low at ambient temperature, the percentages of copper dissolved in the presence of hydrogen peroxide (H₂O₂) and ferric sulfate (Fe₂(SO₄)₃) after 20 h of mechanochemical leaching reached 28% and 33%, respectively. Given the efficiency of the developed method and the facts that it does not require the use of an autoclave and can be conducted at room temperature and atmospheric pressure, it represents an economical and easy-to-use method for the leaching industry.     

多层次测试包:一种用于系统层设计的C/C++门组件层故障模拟的测试包

提出了一种多层次测试包(MLT)用来测试系统层的设计.该包可以被用来测试由门组件层C+ +代码和C+ +复杂函数构成的混合设计.电路部件在高功能层上被描述,而C+ +函数被用来描述门组件层的部件.测试工具可用高层C+ +函数的模拟来用于门组件层部件.使用这个包避免了将被测试部件转换成硬件描述语言,同时也提高了测试应用程序的模拟速度.     

人体热舒适参数与舱室热环境双向耦合研究

现有驾驶舱热系统偏向于研究热环境的气流组织参数,较少考虑甚至不考虑人体热调节的作用,使驾驶舱热系统的仿真结果在评估人体热舒适性时准确度不高.采用CFD(computational fluid ynamics)方法,通过能量方程、RANS(reynolds-averaged navier-stokes)方程以及N-s (...     

基于导热微分方程新解法的人体温度仿真

传统直角坐标系下的导热微分方程与人体几何特性匹配较差,造成方程求解精确度低,从而引起人体温度仿真值与真实值偏差较大。针对这一问题,文章基于人体椭圆柱体的几何特性,将导热微分方程从直角坐标系转化为椭圆柱坐标系,采用交替方向全隐格式的有限体积法对方程进行离散、求解;同时给定初始温度以及边界条件,对人体温度进行仿真。将本文仿真结果与传统导热微分方程的计算值以及实验值进行对比,得出本文的计算方法正确且计算精度较高。     

Genome-wide association and large-scale follow up identifies 16 new loci influencing lung function

Pulmonary function measures reflect respiratory health and are used in the diagnosis of chronic obstructive pulmonary disease. We tested genome-wide association with forced expiratory volume in 1 second and the ratio of forced expiratory volume in 1 second to forced vital capacity in 48,201 individuals of European ancestry with follow up of the top associations in up to an additional 46,411 individuals. We identified new regions showing association (combined P < 5 × 10(-8)) with pulmonary function in or near MFAP2, TGFB2, HDAC4, RARB, MECOM (also known as EVI1), SPATA9, ARMC2, NCR3, ZKSCAN3, CDC123, C10orf11, LRP1, CCDC38, MMP15, CFDP1 and KCNE2. Identification of these 16 new loci may provide insight into the molecular mechanisms regulating pulmonary function and into molecular targets for future therapy to alleviate reduced lung function.