Acceptance of Sharīʿah‐compliant precious metal‐backed cryptocurrency as an alternative currency: An empirical validation of adoption of innovation theory

In the crypto world, there is a proverbial (and literal) gold rush now occurring. Currently, more than 37 gold‐backed cryptocurrency companies have now emerged. Interestingly, some of them also claim to be Sharī?ah‐compliant. Introducing precious metal‐backed cryptocurrencies is perceived to be an innovation among global payment systems, hampered in part by lack of supporting empirical evidence. Therefore, this research investigates potential users' tendency to adopt a Sharī?ah‐compliant precious metal‐backed cryptocurrency. As such, this study adopts an extended adoption model, which consists of eight factors. Partial least squares structural equation modeling (PLS‐SEM) analysis was conducted on data elicited from economic active residents in Klang Valley from questionnaires. Overall, it was found six out of the eight constructs specified to influence the adoption of precious metal‐backed cryptocurrency were statistically significant where 54.5% of the variation in adoption of PMBC can be explained by the structure model provided by this research. It was also found 63.55% of the respondents are willing to adopt precious metal‐backed cryptocurrency in their future transactions.     

提高广西有色金属产业技术创新能力的对策研究

文章在介绍广西有色金属产业发展总体状况的基础上,重点分析了广西有色金属产业技术创新的现状与存在问题,最后提出提高广西有色金属产业技术创新能力的对策。     

Herding,anti-herding behaviour in metal commodities futures: a novel portfolio-based approach

The purpose of this article is twofold. Motivated by the heated debate on the financialization of commodities, we examine the existence of herding behaviour in metal commodities futures. In order to identify any time-dependent properties reflected in time-varying parameters, we employ the overlapping rolling window regression technique. The empirical evidence confirms a time-varying anti-herding behaviour before the global financial crisis and the absence of herding or anti-herding behaviour during the crisis. Next we attempt to formally establish the link between the documented anti-herding behaviour and portfolio management with the use of dynamic conditional correlations via the DCC-GARCH family multivariate modelling. After specifying the correlations, an in-sample recursive dynamic Markowitz portfolio is constructed and monitored. By doing so, we attribute the anti-herding behaviour to different portfolio positioning and rebalancing. On the other hand, in the absence of herding or anti-herding behaviour, we document a shift in the correlations and covariances of the commodity futures especially during the crisis, resulting in a decrease of the portfolio weights together with a substantial cash flow towards the risk-free asset.     

大庆市土壤环境质量时空变化特征分析及污染源分析

以大庆环境监测站提供的数据为依据,通过对大庆市1996~2010年土壤环境质量监测数据的数学分析,揭示了15年间大庆在石油资源开发和快速城市化过程中土壤重金属含量的时空变化特征。采用单项指数法(Pi)和Nemerow的综合污染指数(P)对大庆土壤质量进行评价。结果表明:大庆四个不同功能区(牧业草原区、农业开发区、石油化工区、油田开发区)中油田开发区综合污染指数最高,其次为石油化工区,牧业草原区综合污染指数最低。采用As、Cd、Cu、Pd四种重金属作为主要评价因子,其中对大庆土壤重金属污染贡献值最高的是Pd,其次为Cu。近15年来,四个功能区中的重金属浓度总体均呈上升趋势。另外通过对土壤中重金属来源进行测定和分析,结果显示目前落地原油并未对土壤产生重金属污染,但废钻井液对土壤重金属污染有较大影响。     

案例教学法在金属腐蚀课程教学中的应用研究

本文以培养学生工程实践能力和创新能力为目的,分析了工科类专业实施案例教学法的必要性,在遵循案例教学法实施原则的基础上,通过对金属腐蚀课程进行案例教学法的实践,初步构建了以学生为中心,以学生实践为主体,以培养学生创新素质为基本价值取向的金属腐蚀课程课堂案例教学模式,以期为开展创新型材料工程师人才培养模式提供参考。     

基于表面等离子体激元的金属结构滤波器设计

金属表面等离子体激元所具有的近场增强、表面受限、短波长等特性为亚波长尺度的金属结构中光场局域化提供了可能性。利用它可以实现纳米级别、亚波长尺度内的高质量滤波。本文建立在表面等离子体理论的基础上,设计出一种方形腔结构,编写程序利用matlab和时域有限差分法模拟,并通过改变结构的宽度、高度和耦合长度等参数,分析光波通过该金属结构后的透射性质,结合振幅分布,总结了其在滤波器中的应用。     

金属拉伸实验数据小波变换数字滤波方法研究

小波变换具有良好的时频局部化能力。当采用小波变换对金属拉伸实验数据进行数字滤波时,不但能滤除干扰信号,而且能很好的保留信号的突变部分,体现信号原貌,这一功能是傅里叶变换所无法比拟的。通过比较傅里叶变换与小波变换对金属拉伸实验数据的滤波结果,表明采用小波变换处理含噪的实验数据,具有良好效果。     

几种典型的土壤污染修复技术综述

土壤污染是当前重要的环境问题之一。本文概述了目前国内外处理污染土壤常用的物理修复、化学修复和生物修复技术以及其研究进展。由于各种修复技术各有所长、各有所短,因此为了克服单一方法的缺点,发挥不同修复技术的长处,对加强研发污染土壤的综合修复技术提出了几方面建议。     

基于TVP VAR模型的有色金属价格时变相关性研究

基于TVP-VAR模型,考量有色金属价格时变相关性.结果显示,铜价、铝价及锌价之间存在显著的正向相关关系;一种有色金属价格发生变化,其他两种有色金属的价格通常出现正向响应,并且这种响应的强度是时变的.时点脉冲函数结果表明,不同时点下有色金属价格之间的相关关系是不同的,但大多时点下表现为正相关关系.     

进口含贵金属物料的表征和属性鉴别

采用X射线荧光光谱仪、X射线衍射光谱仪及标准方法等分析技术手段,对进口4种含贵金属物料样品进行表征,结果为:样品1外观为潮湿的黑色粉末,夹杂有金属光泽的小颗粒,主要由SiO₂(石英)和CaCO₃(方解石)组成,Au量为21.0 g/t,Ag量为160.0 g/t;样品2外观为灰色圆柱状颗粒,夹杂少量白色圆球状颗粒,主要由Al₂O₃和Ag组成;样品3外观为土黄色粉末夹杂大小不等结团状,水分含量为24.6%;样品4外观为灰色圆球状颗粒,主要由Al₂O₃组成。将样品的外观、组成等特征,与报验提供的样品来源、含贵金属物料、含贵金属产品及相关文献等进行比对,依据《中华人民共和国固体废物污染环境防治法》与《固体废物鉴别标准通则》GB 34330-2017判定:样品1来源为石英脉型金矿或尾矿经富集的含金矿物,其金含量达到金精矿品位要求,不属于固体废物;样品2为含银废催化剂经高温处理的产物,样品3为湿法冶炼提取锌或其他有价金属后的浸出渣,样品4为含钯废催化剂经高温处理的产物,样品2、样品3和样品4属于目前我国禁止进口的固体废物。