凭祥金矿风化剖面中砷的地球化学研究

利用连续提取法结合电子探针分析对龙塘金矿风化剖面中砷的赋存状态及其地球化学行为进行了研究。结果表明金矿区表层土壤中砷含量达588mg/kg,是土壤质量标准的十几至几十倍，该土壤已受到砷的严重污染。风化母岩中砷主要赋存于含砷黄铁矿与毒砂之中，而风化样品中砷主要赋存于晶质氧化铁中，其次为非晶质氧化铁之中，其他三个结合态相对较少。风化初期，含砷黄铁矿与毒砂风化溶解，其中大部分砷被风化溶液淋失，其他砷被氧化铁吸附。非晶质氧化铁结合态砷在风化过程中显示先升后降的趋势，而晶质氧化铁结合态砷则逐渐升高。雨水对表层土壤的冲刷、风化母岩中硫化物的风化溶解、风化产物中氧化铁在饱和条件下的溶解等都会使剖面中的砷释放出来，对周围环境造成潜在的威胁。     

臭氧与TiO2/UV协同降解对氯苯酚

利用O3／UV、TiO2／UV和O3／TiO2／UV降解对氯苯酚表明，臭氧与TiO2／UV具有明显的协同作用，如在本实验条件下降解5min后，上述3者对对氯苯酚的去除率分别为55％、10％和77%。O3／TiO2／UV协同作用的本质是由于臭氧能带走二氧化钛光致电子空穴对中的电子，从而产生了更多的羟基自由基，加速了有机物的降解。     

溧阳两次中强震的灾情与相关异常

本文对1974年4月22日和1979年7月9日在江南水乡溧阳先后发生的两次中强地震的灾情进行回顾以及地方地震部门在抗震救灾中应发挥的作用进行总结,同时,对这两次中强震前的相关异常进行分析,这样可为我们今后的地震预报提供参考,也可为我们以后的抗震设防和抗震救灾提供借鉴。     

导数示波极谱法测定农药中的三氯乙醛

本文报导用导数示波极谱法直接测定农药中微量三氯乙醛的方法。实验结果表明,三氯乙醛在0.010mol/L NH_4Cl、5.00×10~(-4)mol/L EDTA和2.00×10~(-6)mol/L四乙基溴化铵组成的底液中,于滴汞电极上产生灵敏的峰电流。峰电位为-1.55V(Vs·S·C·E·)。检测下限为3.00×10~(-7)mol/L;浓度在3.00×10~(-7)～1.00×10~(-3)mol/L范围内与峰电流呈良好的线性关系。     

Current status of applying microwave-associated catalysis for the degradation of organics in aqueous phase – A review

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染料中铅的测定

硝酸和双氧水进行消解 ,用石墨炉原子吸收光度法测定染料中的铅。     

钙基膨润土钠化改型的影响因素探讨

在自然界,钙基膨润土的资源量大,钠基膨润土的资源量小。前者物化性能和使用效果差,一般均须用人工钠化改型来提高其物化性能和使用效果。研究认为,钠化效果受膨润土自身质量、钠化改型剂、钠化改型剂添加量、钠化时间和钠化工艺等诸多因素影响。     

Carbon reduction potential and cost evaluation of different mitigation approaches in China's coal to olefin Industry

Coal-based olefin (CTO) industry as a complement of traditional petrochemical industry plays vital role in China's national economic development. However, high CO₂ emission in CTO industry is one of the fatal problems to hinder its development. In this work, the carbon emission and mitigation potentials by different reduction pathways are evaluated. The economic cost is analyzed and compared as well. According to the industry development plan, the carbon emissions from China's CTO industry will attain 189.43 million ton CO₂ (MtCO₂) and 314.11 MtCO₂ in 2020 and 2030, respectively. With the advanced technology level, the maximal carbon mitigation potential could be attained to 15.3% and 21.9% in 2020 and 2030. If the other optional mitigation ways are combined together, the carbon emission could further reduce to some extent. In general, the order of mitigation potential is followed as: feedstock alteration by natural gas > CO₂ hydrogenation with renewable electricity applied > CCS technology. The mitigation cost analysis indicates that on the basis of 2015 situation, the economic penalty for feedstock alteration is the lowest, ranged between 186 and 451 CNY/tCO₂, and the cost from CCS technology is ranged between 404 and 562 CNY/tCO₂, which is acceptable if the CO₂ enhanced oil recovery and carbon tax are considered. However, for the CO₂ hydrogenation technology, the cost is extremely high and there is almost no application possibility at present.     

Highly time-resolved aerosol characteristics during springtime in Weizhou Island

A single particle aerosol mass spectrometer was deployed to measure the changes of single particle species and sizes during March 2015 in Weizhou Island of the Beibu Gulf, Guangxi province, South China. In this campaign, a total of 3,100,597 particles were sized, and 25.8%particles with both positive and negative mass spectrum were collected and 24.8%characterized in combination with the ART-2 a neural network algorithm. The distribution of sized particles was mainly in from 520 to 600 nm, and the diameters ranging from 340 to1000 nm accounted for above 90%. Eight types of particles were classified: Elemental Carbon containing(EC), Organic Carbon containing(OC), EC and OC combined containing particles,Na containing particles, K containing particles(K), Levoglucosan containing particles,mineral containing particles, and Heavy Metal containing particles(HM). EC, OC and K were the major containing particles, which accounted for 84.3% in the eight types particles. The relative ratio and size distribution of the three types were EC(48.1%, 620 nm), OC(12.7%,440 nm), and K(23.5%, 600 nm), respectively. The three types of particles were a bit increasing ratios compared with those in clean periods during haze pollution periods.Combined with the back-trajectory results from the Hysplit-4 model and local pollution sources revealed that the ambient air quality on the Weizhou Island may be influenced by biomass burning in the Indochina Peninsula(biomass burning in the Indochina Peninsula)from the transportation on higher level atmospheric layer and by mainland of south China located northeast of Weizhou Island on the ground.     

Preparation of MgCr<Subscript>2</Subscript>O<Subscript>4</Subscript> from waste tannery solution and effect of sulfate,chloride, and calcium on leachability of chromium

This paper presents a study regarding the preparation of MgCr₂O₄ from waste tannery solution, and chromium leaching behavior is also investigated with varying amounts of sulfate, chloride and calcium. The phase transformation, crystallinity index and crystallite diameter were characterized using XRD, FT-IR and thermal analysis. A well-crystallized MgCr₂O₄ was successfully prepared at 1400 °C. The sintering temperature had a major impact on the formation of MgCr₂O₄ compared with sintering time. The MgCr₂O₄ phase was observed initially at 400 °C and its crystallite diameter increased with increasing temperature. The concentration of total chromium leached and Cr(VI) decreased gradually with increasing temperature. The considerable amount of Cr(VI) was found in the leachate at 300–500 °C caused by Cr(VI) intermediary products. Sulfate and chlorine could impact the transformation efficiency of chromium adversely, and chlorine has a more significant effect than sulfate. The presence of calcium disturbed the formation of MgCr₂O₄ and new chromium species (CaCrO₄) appeared, which resulted in a sharp increase in the concentration of leached Cr(VI). Incorporating Cr(III) into the MgCr₂O₄ spinel for reusable products reduced its mobility significantly. This was demonstrated to be a promising strategy for the disposal of chromium containing waste resource.