Advanced Materials Research Vols. 1010-1012

Abstract: Nitrate salt is important heat transfer and storage medium in solar thermal power system, but nitrate salt leakage and pollution in groundwater is seldom investigated. In this paper, the nitrate salt leakage and migration in the soil after rainfall are simulated and analyzed. During the nitrate leakage process, the liquid nitrate will solidify, and then a thin solidification layer of nitrate forms. According to the simulation result, the radius of the leakage opening mainly affects the radius of nitrate solidification layer, while the leakage velocity will influence the radius and thickness of salt layer. During the nitrate migration process after rainfall, the nitrate will gradually migrate to the groundwater, and the final migration domain of nitrate in the soil will be mainly determined by the radius of nitrate solidification layer.

Abstract: To survive an ever-changing environment, plants must respond to changes in the environment constantly and evolve great plasticity to adapt these changes whilst maintaining developmental and growth processes. Light and temperature are two major factors among numerous environmental stimuli. Their regulations are involved in various developmental and metabolic processes. Moreover, studies have revealed that light and temperature regulate physiological processes like seed germination, hypocotyl elongation and flowering synergistically. This indicates connection exists between these two stimuli response. In this study, we adopted microarry analysis and bio-informatics approaches to identify the relationship between light and temperature sensing pathways. The results of these works, combined with literature research results, shown that multiple hormone-synthesis and -transport genes respond to both light and temperature stimuli, and phytohormones shore up the relationship between light and temperature signaling transduction pathway.

Abstract: An approach is described for the in situ measurement of CO₂ flux at various depths in arid soil. In this method, a sampling tube is inserted to the desired soil depth in a pre-drilled hole, and an infrared CO₂ gas analyzer connected to the sampling tube is used to quantify CO₂ (based on absorption of CO₂ by infrared rays). In a preliminary test, the method was used to quantify CO₂ concentration and flux in an arid grassland soil. The results indicated that it could be used to quantify CO₂ flux in soil from 0–200 cm depths , and should be useful for estimating CO₂ flux and storage at different soil depths, for estimating the change in CO₂ emission from soil caused by change in land-use/land-cover, for assessing the rate of restoration of soil fertility and other soil properties in arid soils, and for monitoring leakage from geological storage of CO₂.

Abstract: A kind of online or portable online odor detector is needed for continuously monitoring the concentration and tracing the source of the odor which is one of the atmosphere pollution. Combining gas chromatograph (GC) and micro-fluidic chip technology, we present a kind of odor detecting system which using micro-fluidic chip for gas separator and photo ionization detector (PID) for sensor. The 115×60×6mm micro-fluidic chip, etched a micro channel of 1mm diameter and 1.8m length inside, is filled by polyethylene glycol as stationary phase according to the type and character of odor. Respectively using micro-fluidic chip and stainless steel packed columns, the acetone detecting experiments prove that corresponding values of the theoretical plates numbers are 2156 and 1250, in addition, the values of their tailing factor are 1.20 and 1.33. The separation experiment between acetone and ethyl alcohol in the chip illustrate the degree of separation is 3.1.

Abstract: By the chemical sequential extraction method, various chemical speciation of phosphorus were extracted from shallow sediments of Nansi Lake. Aiming at the existing problems of lower concentration of phosphorus, the method combined the original sequential extraction and Mo-Sb Anti spectrophotometric method was improved to reduce the interference caused by stratification and chromogenic reaction. In addition, due to the presence of excess sodium dithionite, the extracting solution need to be diluted during occlude phosphorus (Oc-P) extraction process.

Abstract: The water quality model is an efficient tool for water pollution control, water quality planning and environmental management. In accordance with the need of prediction, analysis and management of water quality, this article presents different application conditions for various water quality model, including zero-dimension, one-dimension, two-dimension and multidimensional. Then the application of water quality model in different areas are summarized here.

Abstract: Based on the meteorological observation data of 4 acid rain monitoring stations (Shaowu Station, Fuzhou Station, Yong’an Station and Xiamen Station) during 2007 to 2012 in Fujian Province, the characteristics of the acid rain were analyzed. The results showed that acid rain pollution was common in Fujian Province while showing a reducing trend overall. The time from 2007 to 2010 was acid rain pollution period of large precipitation acidity and high strong acid rain frequency. And the time from 2011 to 2012 was acid rain improving period with precipitation acidity weakening and strong acid rain frequency declining. It showed an obviously seasonal feature for acid rain. Acid rain pollution was relatively heavy in winter while light in summer in Fuzhou, Shaowu and Xiamen. But the seasonal distribution in Yong’an was just the opposite. There were large differences in the degree of acid rain pollution in different regions. The acid rain pollution in Shaowu was heaviest belonging to the strong acid rain area. And the second was Fuzhou belonging to the moderate acid rain area. Xiamen and Yong’an belonged to the light acid rain area with lighter pollution. The acid rain pollution showed various degrees of improvements in Shaowu, Fuzhou and Xiamen. Especially in Fuzhou the improvement was particularly evident as the best condition in recent years. While in Yong’an the acid rain pollution had aggravated somewhat in recent years with the acid rain frequency increasing and the precipitation acidity enhancing.

Abstract: Organochlorine Pesticides (OCPs) is a kind of typical Persistent Organic Pollutants (POPs) with high toxicity, semi-volatility, environmental persistence and bio-magnification. Because of its large number of application in history, the residue level of OCPs in environmental media is rather high. This paper summarizes the existing status of the residue level and distribution of OCPs in China’s lakes in recent years, which is helpful to evaluate the pollution status of the OCPs in lake and provides a basis for effective governance.

Abstract: Effluent of aniline wastewater treatment from a company was isolated and fractionated by resin adsorption method into six different fractions. These fractions are operationally categorized as hydrophobic acids (HOA), hydrophobic bases (HOB), hydrophobic neutrals (HON), hydrophilic acids (HIA), hydrophilic bases (HIB) and hydrophilic neutrals (HIN). The dissolved organic carbon (DOC), ultraviolet-visible (UV) and genotoxicity of each fractions were determined. The results showed that hydrophobic matter is the main fractions of DOC and makes the main contributions to the genotoxicity of effluent of aniline wastewater treatment.

Abstract: Based on meteorological observation data and environmental monitoring data of Changsha in the period from 1970 to 2012, this paper analyzes the distribution characteristics and import factors of the haze weather in Changsha. The results show that in the recent forty-three years, haze in Changsha is on the rise as a whole, and the haze weather mainly concentrates in autumn and winter. During the occurrence of the haze weather, the annual sunshine durations and the annual mean temperature are positively correlated with the haze weather, the annual precipitation is negatively correlated with the haze weather, and the concentration of PM_2.5 is significantly positively correlated with the occurrence of the haze weather, with the correlation coefficient of 0.893, indicating that PM_2.5 is the primary factor for the haze weather. Therefore, the control of PM_2.5 will be the key in reducing the haze pollution and improving the ambient air quality.