Engineering Plasmonic Gold Nanostructures and Metamaterials for Biosensing and Nanomedicine

The fields of biosensing and nanomedicine have recently witnessed an explosion of interest and progress in the design and study of plasmonic Au nanostructures (p‐AuNSs) or metamaterials geared towards a broad range of biological and biomedical applications. Due to their tunable and versatile plasmonic properties, such artificially engineered p‐AuNSs and materials have the potential to push biosensor sensitivity towards the single‐molecule detection limit, enabling new bioimaging modalities and new analytical techniques and tools capable of single‐molecule detection, analysis and manipulation, and to revolutionize the diagnosis and treatment of many diseases, including cancers. This report summarizes and highlights recent major advances in the emerging field of bioapplication‐oriented engineering of p‐AuNSs and hybrids, focusing on design considerations and ways to carry them out. A brief overview of the optical properties of p‐AuNSs is introduced, and then the importance of plasmonic engineering and future promising research directions and challenges in the field are discussed.     

上盘进路下盘水平分层联合采矿法试验研究

三山岛金矿是我国特大型地采黄金矿山之一,也是地采机械化装备程度最高的黄金矿山。新立矿区原设计采用脉内点柱式上向分层充填采矿法,因上盘矿岩比较破碎、开采难度比较大、矿石贫化损失率比较高,为此设计了独特的上盘进路与下盘水平联合采矿法开采矿石。试验结果表明,这种联合采矿方法不仅在技术上先进、经济上适用,而且安全可靠,可为地质条件相类似的矿山借鉴。     

Effects of Surface Orientation and Temperature on Tensile Deformation of Gold Nanowires

Molecular Dynamics (MD) simulations have been performed using the EAM potential to investigate the deformation behaviors and mechanical properties of <100>/{100} gold nanowires with square cross-section at a certain strain rate under different temperatures ranging from 10 K to 700 K. It is found that <100>/{100} gold nanowires at high temperatures tend to form the extended stable nanobridges-Helical Multi-shell Structure (HMS), which is similar to the deformation behavior of <110> gold nanowires at room temperature reported in the previous experimental observations and simulations. The effect of temperature on the mechanical properties and deformation behaviors of gold nanowires was analyzed. The results showed that the yield stress and modulus of the nanowires with rectangular cross-section decrease with increasing temperature at certain strain rate. In addition, we investigated <100>/{110} and <110> gold nanowires under the same conditions, and found that the surface orientation plays a significant role in the formation and stability of gold nanobridges. Based on these investigations, we discussed the combined effects of surface orientation and temperature on the mechanical properties and structural behaviors. Moreover, the length of HMS and toughness of nanowires with different orientations was analyzed as a function of temperature.     

采用磁场强化浸出提高某含铜难浸金矿浸出率的试验研究

某含铜难浸金精矿常规硫脲浸出率仅48.71%,采用细菌预处理及磁场强化浸出后金浸出率可达92.86%。在常规硫脲浸出、低氧细菌预处理及氧化渣浸金试验中添加磁场可明显促进金的浸出,提高浸出率。     

焙烧氰化渣氯化挥发提金的研究

对山东某焙烧氰化渣进行了氯化挥发提金的研究,将原料配入CaCl₂造球、烘干,将球团在不同条件下焙烧,分析焙烧前后的元素含量变化。结果表明：氰化渣中配入4%的CaCl₂造球烘干,在1 050 ℃下焙烧,金挥发率能达到85.93%,且在该温度下未发生熔融,证明使用氯化挥发法提取焙烧氰化渣中的金是可行的。实验中还发现,CaCl₂的分解温度远低于适宜的挥发温度,因此升温时间、中温停留时间过长会导致CaCl₂提前分解,影响金的挥发。     

含砷难处理金精矿的催化氧化酸浸（COAL）新工艺开发

介绍了催化氧化酸浸（COAL）新工艺开发及产业化的情况,该工艺可以在100 ℃及0.4 MPa氧分压条件下对含砷金矿进行处理,金和银的回收率都可达到92%～96%。较低的工业压力和温度使设备简单、易于开工,基建投资和维修操作费用均较传统加压浸出工艺明显降低。在小型试验基础上,开发出100 m3加压浸出反应釜,并在招远金矿建成了100 t/d的工业试验及生产厂,工业试验证实金和银回收率分别为 93%～95%和 92%～96%,与小型试验结果一致。在操作参数及设备形式调整后,本工艺亦可适用于高砷高碳金精矿的处理。     

延边东部杨金沟金矿床成矿时代与成矿物质来源

杨金沟金矿床位于吉林省珲春市春化镇,大地构造位置上地处兴蒙造山带最东端。为了确定其成矿时代以及成矿物质来源,选取金矿石中与金矿化密切相关的辉钼矿和黄铁矿分别进行Re-Os定年和S同位素测试分析。辉钼矿的Re-Os等时线年龄为(247.6±5.8)Ma,模式年龄的加权平均年龄为(250.6±1.8)Ma,结合已有白云母Ar-Ar测年和含矿岩体锆石U-Pb测年结果,确定杨金沟金矿床的形成时代为晚二叠世末至早三叠世初。金矿石中黄铁矿的δ~(34)S值介于0.59‰~2.70‰,接近陨石硫δ~(34)S值,故硫源主要来自于上地幔;辉钼矿的Re质量分数介于2.87×10~(-4)~5.64×10~(-4),也表明其成矿物质主要来源于地幔。根据成矿地质条件、矿床地质特征、成矿物质来源、成矿构造背景以及同类矿床对比研究,认为杨金沟金矿床是东北地区晚古生代金矿床的典型代表,其成因上属与造山作用有关的中温热液脉型金矿床。