有色金属行业环境风险联动控制体系研究--基于“政府、社会、行业”三重视角的PSI博弈模式

有色金属行业在国民经济发展中占据着重要地位,但其高能耗、高污染的发展模式导致行业的环境风险持续加剧,加强对有色金属行业环境风险的管理尤为迫切。文章结合有色金属行业的发展实际,综合分析了在政府（P）、社会（S）和行业（I）三级因素影响下的有色金属行业环境风险的控制要素,利用博弈模型构建了基于PSI博弈模式的有色金属行业环境风险联动控制体系,并结合紫金矿业集团污染事故进行案例分析,提出了实行该联动控制体系的配套措施。     

Characterisation and Diagnosis of Rural—Urban Interface Farming in the Tu Liem and Thanh Tri Districts of Hanoi City,Vietnam

A research project was carried out in two areas in the outskirts of Hanoi city using a combination of qualitative and quantitative methods. The objective was to study interactions among the vegetable farming systems and the peri-urban context within which they are situated. The farms studied were characterised as small-scale farms that use high inputs of soil amendments and pesticides for diversified crop rotation systems. The main source of irrigation water and nutrients for vegetable farming in southern Hanoi is wastewater from the To Lich River. In northern Hanoi, irrigation water is obtained directly from the Red River and nutrients are supplied through high fertiliser inputs. The concentrations of COD (144–287 mg l^?1), N-NH₄ ⁺ (1–25 mg l^?1), PO₄ ^3? (0.5–4 mg l^?1) and coliform (525 × 10³?28 × 10⁶ MPN 100 ml^?1) along the To Lich River was much higher than the limits specified in the Vietnamese standard for water used in agriculture. A higher Cu content in soil in Phuc Ly seems to be linked to the high input of chicken manure at the site. However, the contents of heavy metals in irrigation water, in vegetables and in the soil surface layer at the two sites were lower than the Vietnamese maximum permissible levels.     

污水处理厂污泥重金属含量及其浸出毒性分析——以上海某污水处理厂为例

为了评价污水处理厂污泥及其浸出液的潜在生态环境风险,以上海嘉定区某污水处理厂为例,采用硫酸/硝酸法和醋酸缓冲溶液法对污泥进行重金属总量和浸出毒性检测分析。同时,也研究了浸出液pH值、浸出时间及消解条件对浸出的影响。试验结果表明：1）污泥中Cu,Zn,Ni和Cr的含量分别是城市污泥中相应物质的平均含量的20,7.5,15和13倍,而Pb和Cd的含量与城市污泥的平均含量差不多;2）污泥中Cu与Cr主要以稳定形态存在,不同浸提方法下的浸出量相当,对于Zn和Ni,醋酸缓冲溶液的浸出量分别约为硫酸/硝酸溶液的22倍和18倍;3）浸出时间为20 h时浸出达到平衡,浸出液pH值对污泥重金属浸出能力的影响,因重金属元素种类的不同而存在较大差异,电热板消解和微波消解对浸出几乎没有影响;4）醋酸缓冲溶液制备的浸出液中,Ni的浸出质量浓度为16.3 mg/L,高于鉴别标准限值5 mg/L,而硫酸/硝酸浸提方法中重金属浸出浓度均未超过规定值。因此,该污水处理厂的污泥不适合卫生填埋,应积极寻求新技术对污泥进行合理处置并减少其潜在生态环境风险。     

基本有色金属期货市场价格波动实证分析

依据铜、铝和锌三种典型性基本有色金属在金融危机前后的期货价格波动数据,运用分解-合成框架和时变TVP-VAR分析模型,考量影响基本有色金属期货价格波动重大事件和长期趋势价格波动的因素及价格时变特征。结果发现：铜、铝和锌三种基本有色金属期货的价格走势基本一致,且与中国宏观经济密切相关,其价格的最低点都出现在金融危机期间,而价格的最高点基本都出现在经济繁荣期;基本有色金属价格存在同涨同跌关系,而且涨跌幅基本趋势相一致。鉴此,可以对具有周期变化特征的基本有色金属价格走势进行预测,并规避价格波动的风险。     

Benchmarks in the spotlight: The impact on exchange traded markets

The Fix for precious metals is a global pricing benchmark that provides pricing and liquidity provision for market participants. We exploit the gradual change in the century old auction process to quantify the efficiencies related to more transparent pricing. Our focus is in the market impact of this change on exchange listed products. We find that reforms to the Fix have reduced quoted and effective bid-ask spreads and improved overall market depth. The results imply a positive spillover effect stemming from timelier and more accurate pricing information. The conditions under which we observe the benefits from transparency are related to product liquidity and the degree of market segmentation.     

Representative account or greenwashing? Voluntary sustainability reports in Australia's mining/metals and financial services industries

Why are more and more companies voluntarily issuing costly, potentially exposing standalone sustainability reports on environmentally and socially problematic issues? Using legitimacy theory, this study analyses ways companies seek to strategically enhance legitimacy by leaning towards either ‘representative’ reporting of both favourable and unfavourable information especially in an industry's highest impact domains, or ‘greenwashing’ (including whitewashing non-environmental issues), which downplays unfavourables and high-impact domains and highlights favourable but less relevant points. Content analysis compared Global Reporting Initiatives (GRI) reports from 2011 to 2019 by Australian financial services companies (107 reports) and mining and metals companies (122). Specifically, to critique reporting quality in fine grain, it disaggregated results into levels (from omission to full quantitative treatment) of disclosure of good/bad/neutral news indicators and violation-related/non-violation-related ones and identified highest impact domains. Neither industry's reporting was very representative. Relatively though, mining and metals leant towards representation: fuller disclosure on environmental aspects (its highest impact domain), including unfavourables: bad and violation-related indicators. Financial services companies only led in disclosing neutral social indicators, not bad or violation-related ones, so leant towards greenwashing. Results also suggest that after the GRI clarifying materiality principle in 2016, financial services disclosure quality dropped further by de-emphasising environmental without lifting social disclosures, while mining and metals' stayed unchanged. The results confirm and better specify widely indicated reporting weaknesses, contributing to content analysis methodology and legitimacy theory. This arms guideline setters, investors and other stakeholders to better evaluate/design reports and might encourage firms to voluntarily improve disclosures.     

Metal prices made in China? A network analysis of industrial metal futures

In addition to being the world's greatest consumer and producer of industrial metals, China now also features the most actively traded industrial metal futures contracts worldwide. To examine China's role in the global price formation process of industrial metal futures markets, we use a sample of 29 futures contracts traded on exchanges in the United States, the United Kingdom, India, and China. We estimate vector autoregressive models and conduct variance decompositions, which are then visualized in the form of networks. The results indicate that China, despite its role as key actor in both real and financial industrial metal markets, is a price taker.     

食品中重金属检测方法研究进展

密度大于4.5g/cm~3的金属称为重金属,铅、镉、砷、汞等重金属元素会对人体健康产生严重的影响。重金属在生物体内无法被降解,反而会在生物链的放大作用下富集。因此,重金属检测对维护食品安全具有重要意义。基于此,对食品中重金属检测方法进行探讨。     

酸化铜尾矿基质改良剂的筛选研究

金属尾矿库复垦和生态修复的关键之一是尾矿基质的改良。以安徽铜陵某典型铜尾矿库酸化尾砂为研究对象,利用大麦根伸长毒性试验,结合重金属有效态提取,筛选酸化铜尾矿基质改良剂及其组合。在施加1.9%牛粪厩肥的基础上,随着尾砂pH中和至近中性,有效态重金属（NaNO3提取态）含量及非专性吸附态As[（NH4）2SO4提取态]浓度逐渐降低,但专性吸附态As（NH4H2PO4提取态）含量却持续增加;大麦根长度随Ca（OH）2施加量先增加后减少,在Ca（OH）2施加量为0.9%、pH为5.3时,大麦根最长,即尾砂对大麦根的毒性最低。结果表明专性吸附态As是植物生长主要限制因子。在施加1% Ca（OH）2和1.9%牛粪的基础上,改良剂凹凸棒石、膨润土、沸石和磷矿粉对尾砂pH和大麦根长无显著影响。施加1% Ca（OH）2和1.9%的牛粪是供试酸化铜尾矿较为理想的改良剂组合。     

Asymmetric effect of financial stress on China’s precious metals market: Evidence from a quantile-on-quantile regression

Constructing the China’s financial stress index (CFSI), this paper investigates the asymmetric impact of financial stress on precious metals by employing a novel quantile-on-quantile approach. The results show that precious metals can be used as a safe haven to hedge financial market risks. However, the risk aversion of precious metals varies under different precious metals market conditions. In addition, the structural changes in the effect on precious metals are found after the global financial crisis, reflecting the heterogeneity of the relationship between financial stress and precious metals before and after the global financial crisis. These results have meaningful implications for investors and risk managers.