Simultaneous catalytic removal of NOx and diesel soot particulate over perovskite-type oxides and supported Ag catalysts

A series of perovskite-type oxides and supported Ag catalysts were prepared,and characterized by X-ray diffraction (CRD)and x-ray photoelectron spectroscopy(XPS).The catalytic activities of the catalysts as well as influencing factors on catalytic activity have been investigated for the simultaneous removal of NOx and diesel soot particulate.An increase in catalytic activity for the selective reduction of NOx was observed with Ag addition in these perovskite oxides,especially with 5% Ag loading.This catalyst could be a promising candidate of catalytic material for the simultaneous elimination of NOx and diesel soot.     

Haze insights and mitigation in China: An overview

The present article provides an overview of the chemical and physical features of haze in China, focusing on the relationship between haze and atmospheric fine particles, and the formation mechanism of haze. It also summarizes several of control technologies and strategies to mitigate the occurrence of haze. The development of instruments and the analysis of measurements of ambient particles and precursor concentrations have provided important information about haze formation. Indeed, the use of new instruments has greatly facilitated current haze research in China. Examples of insightful results include the relationship between fine particles and haze, the chemical compositions and sources of particles, the impacts of the aging process on haze formation, and the application of technologies that control the formation of haze. Based on these results, two relevant issues need to be addressed： understanding the relationship between haze and fine particles and understanding how to control PM2.5.     

造纸污泥的流变特性实验研究

造纸污泥是制浆造纸产生的废弃物,含有一定量的热值,将造纸污泥通过管道远距离输送到流化床锅炉焚烧是目前解决造纸污泥的最佳途径。造纸污泥作为高浓度黏稠物料进行管道远距离输送存在很多困难,其流变特性研究是管道输送的重要理论基础。从上述角度出发,介绍了造纸污泥的物理特性和实验仪器,通过对质量分数为28.84%~37.30%的造纸污泥进行系统地测试,绘制了黏度曲线和流变曲线,确定了造纸污泥的流变类型,得出了造纸污泥的流变方程。通过对造纸污泥的流变特性研究,为造纸污泥管道输送设备优化设计以及泵的吸入特性研究提供基本参数。     

Road transport and urban air quality in China

１　ＩｎｔｒｏｄｕｃｔｉｏｎＴｈｅＣｈｉｎｅｓｅｇｏｖｅｒｎｍｅｎｔｈａｓｔａｋｅｎｔｈｅａｕｔｏｍｏｂｉｌｅｉｎｄｕｓｔｒｙａｓｏｎｅｏｆｉｔｓｐｉｌｌａｒｉｎｄｕｓｔｒｉｅｓｏｆＣｈｉｎａ．Ｔｈｅｃｕｒｒｅｎｔｐｅｒｃｅｎｔａｇｅｏｆａｕｔｏｍｏｔｉｖｅｔｒａｎｓｐｏｒｔａｔｉｏｎｏｆｐａｓｓｅｎｇｅｒｓｉｓ４５％,ｗｈｉｌｅｔｈａｔｏｆｃａｒｇｏｉｓａｐｐｒｏｘｉｍａｔｅｌｙ１５％．Ａｕｔｏｍｏｂｉｌｅｎｏｗｐｌａｙｓａｍｏｒｅｉｍｐｏｒｔａｎｔｒｏｌｅｉｎｓｈｏｒｔｒａｎｇｅｔｒａｎｓ…     

Potential acute effects of suspended aluminum nitride (AlN) nanoparticles on soluble microbial products (SMP) of activated sludge

The study aims to identify the potential acute effects of suspended aluminum nitride (AlN)nanoparticles (NPs) on soluble microbial products (SMP) of activated sludge. Cultured activated sludge loaded with 1, 10, 50, 100, 150 and 200 mg/L of AlN NPs were carried out in this study. As results showed, AlN NPs had a highly inverse proportionality to bacterial dehydrogenase and OUR, indicating its direct toxicity to the activated sludge viability. The toxicity of AlN NPs was mainly due to the nano-scale of AlN NPs. In SMP, AlN NPs led to the decrease of polysaccharide and humic compounds, but had slight effects on protein. The decrease of tryptophan-like substances in SMP indicated the inhibition of AlN NPs on the bacterial metabolism. Additionally, AlN NPs reduced obviously the molecular weight of SMP, which might be due to the nano-scale of AlN.     

Construction of WCB-11: A novel phiYFP arsenic-resistant whole-cell biosensor

The prediction and assessment of environmental pollution by arsenic are important preconditions of advocating environmental protection and human health risk assessment.A yellow fluorescent protein-based whole-cell biosensor for the detection of arsenite and arsenate was constructed and tested.An arsenic-resistant promoter and the regulatory gene arsR were obtained by PCR from the genome of Escherichia coli DH5α,and phiYFP was introduced into E.coli DH5α as a reporter gene to construct an arsenic-resistant whole-cell biosensor(WCB-11) in which phiYFP was expressed well for the first time.Experimental results demonstrated that the biosensor has a good response to arsenic and the expression of phiYFP.When strain WCB-11 was exposed to As 3+ and As 5+,the expression of yellow fluorescence was time-dependent and dose-dependent.This engineered construct is expected to become established as an inexpensive and convenient method for the detection of arsenic in the field.     

改性TiO2对X-3B的光催化性能及其降解动力学研究

以活性艳红X-3B为模型化合物,比较了改性前后TiO2光催化活性的变化.试验结果表明,通过改性大大提高了TiO2的光催化活性,Fe3+和Ag+的掺杂量均有一个最佳值,在试验的掺杂范围内Fe3+和Ag+的最佳掺杂量分别是0.1%和0.05%.对其宏观降解反应动力学的研究表明,X-3B在TiO2、Fe3++TiO2和Ag++TiO2 3种催化剂上的光催化降解动力学均能很好地符合Langmiur-Hinshelwood动力学模型.其表观反应速率常数的大小顺序依次是Ag++TiO2＞Fe3++TiO2＞TiO2;吸附平衡常数则是Fe3++TiO2和Ag++TiO2两者基本相等,两者均比纯TiO2大2～3倍.     

Difference between selenite and selenate in selenium transformation and the regulation of cadmium accumulation in Brassica chinensis

Environmental Science and Pollution Research - Se can regulate Cd accumulation and translocation in plants; however, such effects can be controversial because of the differences in plant species...     

Mechanism of dry detoxification of chromium slag by carbon monoxide

Environmental Chemistry Letters - Dry detoxification is a major technology used at the industrial scale for remediation of chromium slag. However, the mechanism of this reaction is poorly known, in...     

Characterizations of temperature effects on sintered ceramics manufactured with waste foundry sand and clay

The objects of this study were to use waste foundry sand (WFS) to manufacture reclaimed resource tiles and to determine the effects of different kiln temperatures on the properties of the reclaimed WFS tiles. In this study, clay was replaced with 0 or 15 % WFS to manufacture tile specimens. Four different kiln temperatures (1000, 1050, 1100, and 1150 °C) were used in this study for the manufacture of tile specimens. The test results showed that using 15 % WFS in the tile specimens allowed the kiln temperature to be lowered by 50 °C. This temperature reduction is helpful for reducing costs and energy consumption and carbon reduction. Moreover, when the kiln temperature increased from 1000 to 1100 °C and the specimens were placed in acidic and alkaline solutions, the weight loss of the tile specimens containing 15 % WFS was half that of the specimens containing 0 % WFS. The acid-alkali resistance of the tile specimens containing 15 % WFS was also improved. This result suggested that the WFS replacement and kiln temperature affected the properties of the tile specimens.