Small-scale mining in China: Assessing recent advances in the policy and regulatory framework

This paper explores the background of a proposed revision to the Mineral Resources Law of China, why and how the law was amended in the past, its salient features and objectives. Of equal importance is an analysis of how this national law, with its attendant regulations and policies, formed the basis for the growth and continued development of China's small-scale mining industry. The Xiaoqingling Gold Mountain case study is shown to justify the necessity and feasibility for formalizing and consolidating small-scale mines in China, and to some extent, the success of the nation-wide ASM resource consolidation policy at a local level.     

Impact factors of the degradation of bisphenol A by nitrocellulose membrane under illumination

Nitrocellulose membrane (NCM) can produce hydroxyl radicals under illumination, which promotes the oxidative degradation of organic pollutants. In this paper, NCM was used to oxidize bisphenol A (BPA) under simulated sunlight. The effects of pH, temperature, light intensity, anion and cation on the degradation of BPA were analyzed. The photodegradation process of BPA was discussed. The optimal photolysis rate was 0.031 min^?1 when the temperature was 30°C, the light intensity was 2.67 × 10⁴ Lux, and the pH value was 9.0. The alkaline environment, temperature and light intensity can promote the photodegradation of BPA. Except for nitrate ions, anions and cations can inhibit the photodegradation of BPA. Compared with cations, anions have a greater inhibitory effect on BPA degradation. The degradation products of BPA by NCM were analyzed by gas chromatographic/mass. This study may provide useful information for the BPA degradation by NCM in complex water samples.     

集成电路产业含氟废水处理工程

介绍采用三级反应一级沉淀为主体工艺,处理集成电路产业含氟废水的实际应用情况和工程治理效果。实践表明,采用本处理技术,能确保出水水质氟离子浓度达到上海市《污水综合排放标准》(DB31/199-1997)的二级标准,即F-浓度≤10mg/L。     

中水回用系统的生物脱臭试验

采样自行设计、构建的生物脱臭塔对生活污水回用处理系统产生的臭气进行净化,获得良好的效果,在空塔停留时间为92s时2个脱臭塔对氨和硫化氢的净化率均达到80%以上,投加活性污泥的1号塔的净化效果更好,表明接种污泥能够促进臭气的净化,其排气中氨含量已优于厂界一级标准,臭气强度接近无臭水平,沸石吸附及微生物氧化分解可能是其中主要过程机理。脱臭塔净化后排气中硫化氢含量仍然较高,达到稍可感觉出和易感觉的水平,表明脱臭塔对硫化氢的净化作用有待进一步提高。氮氧化物因为进气浓度很低,故净化率仅为37%～51%。     

浅论质量共性技术及质量共性技术文件

通过对共性技术的介绍和分析,给出了质量共性技术的概念及定义;并以电子信息系统为例,阐述了质量共性技术的涵盖内容和研究领域,进而探讨了质量共性技术文件的相关内容和编写要求。     

两室堆肥生物反应装置研究

以堆肥过程中物料平衡、热量平衡以及垃圾生物发酵特性为依据,设计了二室堆肥生物反应装置,并通过堆肥试验实际检验反应装置设计的合理性.装置主要结构包括:二室堆肥发酵仓、保温层、通风供氧系统、空气加热系统以及二次污染控制系统.装置的主要特点为:两发酵仓能够独立完成堆肥发酵,也可以实现堆肥一次、二次发酵串联工艺组合;通过二次污染控制系统,可以很好地减少堆肥过程中产生的废水臭气排放;采用空气加热系统,可以快速均匀地加热堆体,以满足不同堆肥工艺的需要.装置在试验研究以及小规模垃圾堆肥处理领域有一定的应用价值.     

超声波/零价铁降解对氯苯胺性能及机理研究

在超声波/零价铁体系中考察了溶液初始pH值、浓度对对氯苯胺降解的影响.在pH值为3～11范围内最佳条件为pH=9;初始浓度为0.1、0.2和0.4 mmol/L时的降解率(180 min)分别为83.2%、63.5%和36.1%.对氯苯胺在单纯铁粉、单纯超声波和超声波/零价铁3种体系中降解符合拟一级反应动力学规律,速率常数分别为6.83×10-4、3.95×10-3和1.01×10-2 min-1,增强因子为218%,表明铁粉与超声波对对氯苯胺降解有明显的协同效应.在体系中加入自由基捕捉剂正丁醇能抑制对氯苯胺的降解,证实对氯苯胺降解主要是依靠羟基自由基的氧化作用.     

活性污泥法动力学模型应用中的参数校核

对国际水协的活性污泥法动力学模型在应用中遇到的参数校核问题进行研究 ,总结了目前常用的三种方法 :专家法、灵敏度分析法和过程工程 (ProcessEngineering)法。分析了每种方法的原理、优点和不足之处 ,列举了实际应用的例子。     

Hydrothermal fabrication and visible-light-driven photocatalytic properties of bismuth vanadate with multiple morphologies and/or porous structures for Methyl Orange degradation

Monoclinic BiVO₄ with multiple morphologies and/or porous structures were fabricated using the hydrothermal strategy. The materials were characterized by means of the XRD, Raman, TGA/DSC, SEM, XPS, and UV-Vis techniques. The photocatalytic activities of the BiVO₄ materials were evaluated for the degradation of Methyl Orange under visible-light irradiation. It is observed that pH value and surfactant exerted a great effect on the morphology and pore structure of the BiVO₄ product. Spherical BiVO₄ with porous structures, flower-cluster-like BiVO₄, and flower-bundle-like BiVO₄ were generated hydrothermally at 100℃ with poly(vinyl pyrrolidone) (PVP) and urea (pH = 2) and at 160℃ with NaHCO₃ (pH = 7 and 8), respectively. The PVP-derived BiVO₄ showed much higher surface areas (5.0-8.4 m²/g) and narrower bandgap energies (2.45-2.49 eV). The best photocatalytic performance of the spherical BiVO₄ material with a surface area of 8.4 m²/g was associated with its higher surface area, narrower bandgap energy, higher surface oxygen vacancy density, and unique porous architecture.     

钙对紫外辐射B胁迫下小麦幼苗若干生物学特性的影响

采用模拟紫外辐射(UV-B,280～320nm)的盆栽实验法,研究钙离子对紫外B辐射胁迫下小麦幼苗若干生物学特性的影响.结果显示,在紫外辐射胁迫下(0.35W/m²,每日照射6h,连续照射7d),2mmol/L钙离子处理的小麦,地下与地上部生长指标均明显低于对照植株(降幅为8.1%～36.1%).而6mmol/L钙离子处理的小麦幼苗,各种生长指标的降幅(3.2%～28.6%)低于2mmol/L钙离子处理的小麦幼苗.表明钙离子具有缓解紫外辐射伤害小麦幼苗的效应,这同钙离子对小麦幼苗部分生理生化指标的影响有关.