镍/铁二元金属对莠去津脱氯特性的影响

为了考察Ni/Fe二元金属对莠去津的催化还原特性,分别以Fe粉和Ni/Fe体系作为还原和催化剂,在酸性条件下对莠去津的脱氯特性进行比较,并讨论了pH值,Ni/Fe配比以及金属添加量等因素对莠去津脱氯效率的影响.结果表明:与Fe粉比较,Ni/Fe体系对莠去津具有很明显的催化脱氯特性.在pH=2时,1.22%(W/W)Ni/Fe体系30min对莠去津的脱氯效率大于90%,相同条件下用Fe粉还原时,90min脱氯效率仅为22.21%通过Fe粉和Ni/Fe表面形态的比较以及实验结果的分析,对Ni/Fe体系的催化还原脱氯机理进行了初步探讨.     

中国5种土壤跳虫对重金属镍的毒性响应

为了研究镍(Ni~(2+))对不同种类跳虫的毒性效应,将曲毛裸长(Sinella curviseta)、四刺泡角(Ceratophysella duplicispinosa)、小原等节(Proisotoma minuta)、茉莉花长角(Entomobrya sp.)、符氏直棘(Orthonychiurus folsomi)5种中国优势跳虫物种,在琼脂培养基环境下分别暴露于Ni~(2+)的8个浓度组中进行24 h、72 h-LC_(50)急性毒性试验和28 d生存试验。利用Bliss法测得其5种跳虫的24 h-LC_(50)分别为52.99、35.91、33.46、23.72、13.50 g·L~(-1);72 h-LC_(50)为46.25、4.54、13.37、14.79、4.35 g·L~(-1)。在28d生存试验中得到成虫存活数量和繁殖情况。结果表明,5种跳虫中曲毛裸长对镍有较强的耐受性,茉莉花长角和小原等节次之,四刺泡角和符氏直棘较弱。符氏直棘与四刺泡角相比,随时间增加对镍的耐受性有相对增强的趋势。此外,Ni~(2+)对跳虫的毒性影响表现出阶段性的阈值效应。Ni~(2+)对5种跳虫的繁殖均有抑制作用。     

Macroporous Ni foam-supported Co3O4 nanobrush and nanomace hybrid arrays for high-efficiency CO oxidation

Herein, we reported the synthesis of well-defined Co_3O_4 nanoarrays(NAs) supported on a monolithic three-dimensional macroporous nickel(Ni) foam substrate for use in highefficiency CO oxidation. The monolithic Co_3O_4 NAs catalysts were obtained through a generic hydrothermal synthesis route with subsequent calcination. By controlling the reaction time,solvent polarity and deposition agent, these Co_3O_4 NAs catalysts exhibited various novel morphologies(single or hybrid arrays), whose physicochemical properties were further characterized by using several analytical techniques. Based on the catalytic and characterization analyses, it was found that the Co_3O_4 NAs-6 catalyst with nanobrush and nanomace arrays displayed enhanced catalytic activity for CO oxidation, achieving an efficient 100% CO oxidation conversion at a gas hourly space velocity(GHSV) 10,000 hr~(-1) and 150°C with longterm stability. Compared with the other Co_3O_4 NAs catalysts, it had the highest abundance of surface-adsorbed oxygen species, excellent low-temperature reducibility and was rich in surface-active sites(Co~(3+)/Co~(2+)= 1.26).     

Fires in tropical forests – what is really the problem? lessons from Indonesia

Fires have attracted interest and generated alarm since the early 1980s. This concern has been particularly evident in tropical forests of Southeast Asia and the Amazon, but disastrous fires in recent summers in Australia, Europe, and the United States have drawn worldwide attention. Concern about forest fires, and related air pollution and biodiversity impacts, led international organisations and northern countries – such as the Asian Development Bank, the European Union, the Food and Agriculture Organisation, the United Nations Environment Programme, the World Bank, and the government of Germany – to undertake fire assessments and provide technical assistance. Nongovernmental organisations, such as the International Union for Conservation of Nature and Natural Resources and World Wide Fund for Nature, have also devoted increased attention to fires. Aiming at prevention of future fires, 40 fire projects and missions costing well over US$30 million have worked in Indonesia over the last 20 years. Despite the money and effort spent on them, fires continue to burn every year. It may appear to some that efforts to address the ‘fire problem’ have not been effective as fires still occur. There remains a lack of clarity about ‘fire problems’, which has, at times, led to the adoption of policies that may have negative impacts on livelihoods, the environment, and the economy. Two ‘simple’ changes in the way fires are considered would significantly improve fire-related policies and initiatives.

TiO2／Ni PECO体系降解DMP的动力学和光电协同作用研究

以采用微波辅助法制备的TiO2／Ni光电极为阳极,纤维状石墨毡材料（graphite felt,GF）为阴极,饱和甘汞电极（saturated calomel electrode,SCE）为参比电极建立TiO2／Ni光电催化氧化（PECO）体系。以邻苯二甲酸二甲酯（dimethy phthalate,DMP）为目标物,研究其光电催化降解反应动力学和光电协同作用。结果显示：DMP的降解符合拟一级动力学规律;当DMP初始浓度一定时,影响DMP光电催化降解速率的因素由强到弱依次为：催化剂有效面积,紫外光强度,曝氧速率,外加偏转电压等。实验证明本体系中光电之间具有协同作用。     

001×14.5离子交换树脂对镍(Ⅱ)的吸附

实验采用离子交换树脂法吸附镍(Ⅱ),树脂选型确定了强酸性阳离子交换树脂001×14.5对镍(Ⅱ)吸附容量最大.用所选的001×14.5树脂吸附镍(Ⅱ)的过程,静态吸附实验表明,转速大于100 r/min时,对树脂吸附的影响可忽略,即基本消除外扩散,pH =7.0时吸附最佳,镍(Ⅱ)吸附率随树脂用量的增加而增大;001×14.5树脂吸附镍(Ⅱ)过程符合Langmuir等温吸附方程,且为优惠吸附;吸附过程符合拟二级动力学模型,吸附过程活化能为E=30.9 kJ/mol,由颗粒内扩散控制;用1 mol/L的硫酸对吸附饱和树脂进行脱附再生,脱附率可达98％以上.     

羰基镍生产中的事故风险及预防对策

分析了羰基镍生产中的危害因素、事故源项和可能出现的概率,确定了风险评价的标准。并根据预测结果划定了警戒防护范围,提出了预防事故的措施和应急计划。     

热成形和热处理对3.5Ni钢力学性能的影响

本文研究了不同厚度3.5Ni低温钢板以不同热成形加热温度和冷却条件成形后的力学性能变化。通过对经历热成形同样加热和冷却条件的母材试板重新进行不同规范的正火和回火,对材料被损坏的性能进行了恢复和提高,为低温钢设备的制造提供了可靠的工艺依据。     

钢渣对酸性含Ni(Ⅱ)废水的吸附-中和作用

以碱性钢渣为水处理材料,研究了其吸附、中和酸性含Ni(Ⅱ)废水的工艺过程和机理。结果表明:在钢渣粒度小于2 mm、用量10 g/L、温度25℃、搅拌强度100 r/min条件下钢渣与Ni(Ⅱ)浓度200 mg/L、pH值4.8的废水反应8 min,可使废水中Ni(Ⅱ)浓度降低到0.25 mg/L,pH值升高到7.2,达到GB8978-1996《污水综合排放标准》的要求。钢渣对酸性废水中Ni(Ⅱ)的吸附符合Langmuir等温吸附式,其饱和吸附量达37 mg/g,反应包括钢渣中碱性物质的水解、Ni(Ⅱ)生成Ni(OH)2沉淀、生成的Ni(OH)2沉淀吸附于钢渣表面等几个过程。X射线衍射分析证明钢渣表面吸附了Ni(OH)2沉淀物。     

含镍废液中镍回收的研究

本文研究了强碱性条件下,以乙二胺为络合剂,用水合肼把二价镍离子还原为单质镍的方法。经过大量实验,镍粉的产率在99％以上,其纯度也在99％以上。通过这种方法,既回收了镍,又降低了对环境的污染,结果令人满意。