Applied Mechanics and Materials Vols. 675-677

Abstract: A simple electrochemical method has been developed for the simultaneous determination of dihydroxybenzene isomers in wastewater samples with poly (glutamic acid) modified electrode (PGA/GCE). PGA/GCE was fabricated by electropolymerization of glutamic acid on a glassy carbon electrode (GCE) through cyclic voltammetry (CV). PGA/GCE showed an excellent electrocatalytic ability towards the oxidation of hydroquinone (HQ) and catechol (CC). With CV and differential pulse votammetric (DPV) measurements, HQ and CC in wastewater samples could be simultaneously analyzed at PGA/GCE. The linear range for HQ and CC were 5 - 100 μM and 2 - 160 μM, with a detection limit of 2.0 μM and 1.0 μM, respectively. Moreover, PGA/GCE exhibited good selectivity and repeatability. The method has a promising application in the monitoring of HQ and CC of wastewater.

Abstract: A simple and rapid SPE-HPLC/PDA method has been developed for the quantitative determination of tetracyclines in soils. An ultrasonic extraction system for the soil samples was confirmed as a combination of a 1:2 ratio of EDTA-McIlvaine buffer solution with methanol by comparing the extraction efficiency of 4 solvents and optimising the combination ratio. The soil extracts were purified and concentrated by Oasis-MAX cartridge followed by HPLC separation and PDA detection. The optimal chromatographic condition effectively separated the object and interfering substance, which can improve the sensitivity of the instrument. The limits of detection were lower than 20 μg·kg^-1, and the limits of quantification were no more than 60 μg·kg^-1 for all compounds in the soil. The recoveries of tetracyclines peaked at levels of 50-500 μg·kg^-1 and averaged at 62.1% to 108.9% with relative standard deviation values of less than 5%. This method was applied to analyse real soil samples from suburban Beijing farmland, and TC and OTC residues were detected in the soil.

Abstract: There were 48 sea water samples collected from Bohai Bay (China) in autumn, 2013. In surface water the heavy metal content from high to low was Cu, Zn, Cr, As, Pb, Cd, Hg, as Zn, Cu, Cr, As, Pb, Cd, Hg in bottom water. Cr and As were up to the first class value of the seawater quality standard except Zn and Cu.

Abstract: This study assessed the ecological risk associated with heavy metals in surface sediments in a specific setting: the Wuhan wetland. Metals were extracted and characterized using the Tessier method, and the morphological distribution characteristics and correlation of Zn, Mn, Fe, Cr, and As were analyzed. The results indicated that heavy metals at the study site mainly exist in residual state forms; the Mn pollution was serious; the potential risk from Cr and As was larger; and the environmental risk from Fe and Zn was lower. In order of potential ecological harm: As > Zn > Cr > Mn. The overall risk of ecological harm was slight, but the individual region has seen moderate ecological damage because of As pollution. Because this element has a significant toxicity level, it is important to remain attentive to the pollution caused by it.

Abstract: Ecological real estate is a re-definition of green building, with its broad conception and inherent realities of social and economic development in the world nowadays. As planning, construction and management of ecological real estate in China is still in the preliminary stage, a method of biodiversity analysis in natural water bodies of real estate is established as a technical way of ecological real estate management.

Abstract: A simple and rapid spectrophotometric method for flow injection determination of sulfite in tan wastewater is described. It was based on the fade reaction of sulfide ion with Ag (I)- (5-Bromo-2-pyridylazo)-5-diethyl-aminophenol (5-Br-PADAP) in NaAc-HAc medium. The optimum conditions allow a linear calibration range of 0.01-1.10 μg ml^-1 sulfide ion. The detection limit is 0.0043 μg ml-1 (S/N=3), and the relative standard deviation for night replicate measurements is 2.1% for 0.5μg ml^-1 of sulfide ion. The procedure has been applied to the determination of sulfide in tannery wastewater. The results were in good agreement with those obtained by methylene blue spectrophotometric method.

Abstract: Air pollution has been deteriorated seriously in Shanghai as a result of urbanization and modernization. Visibility reduction is the most apparent symptom of air pollution. This paper aims to describe the characteristics of visibility and air pollutants in Shanghai, and to investigate the relationship between them. Visibility in Shanghai was higher in summer and lower in winter. The mean value of visibility during 2006-2010 was 17.8km. Air pollution in Shanghai was also serious. In 2010, Shanghai got the relative better air quality compared with the former four years. Air pollutants and visibility were negatively correlated. SO₂ and NO₂ had higher correlation coefficients with visibility than PM₁₀. This suggested that the visibility in Shanghai was mainly due to secondary pollutants.

Abstract: Environmental monitoring of national highway is an important content of China’s environmental monitoring network in the transport field, a part of national environmental monitoring system, and also a significant basis for environmental protection supervision and management of the transport industry. Using the methods of spatial analysis, grid analysis, and optimization through ArcGIS, monitoring objects of Chinese national highway environmental monitoring network had been screened out. Among which, the environmental quality monitoring objects are composed of the national highway sensitive sections nearby or passing through 277 natural reserves, 32 national scenic areas, 7 of the world’s natural and cultural heritage sites, 8 important wetlands, 398 important reservoirs, and 193 state-level sensitive aquatic germ plasm resources conservation areas; and the pollutant emission monitoring objects include 316 long and extra-long tunnels, 539 service areas and 601 toll stations with large traffic volume. Environmental quality monitoring objects and pollutant emission monitoring objects form China’s National Highway Environmental Monitoring Network, which has filled the blank of highway environmental monitoring in the national environmental monitoring network. It will play a positive role in promoting the green development of China's transport industry.

Abstract: By investigating and analyzing PX demand in recent years and the distribution of PX projects in Dagushan chemical industrial park, combining its physical and chemical properties and marine environment near Dalian Dagushan, aim to make environmental assessments on the damage caused by PX to the marine environment and propose appropriate emergency measures.

Abstract: Based on investigation dada on Cr in 1982 in Jiaozhou Bay, this paper analyzed the seasonal and spatial distribution of Cr, and revealed the transfer process of Cr. Results showed that horizontal diffusion and vertical sedimentation were major transfer processes of Cr, which were mainly determined by water exchange and gravity settling. These findings were essential to pollution control and environmental remediation in Jiaozhou Bay. From the point of view of pollution control, reducing the discharge of Cr from the sources was the major countermeasure.