Advanced Materials Research Vols. 518-523

Abstract: North shore of Songhua river is the major development zone in carrying out the program of enlarging urban areas along river regions in Harbin. In this paper, the authors regard urban wetland of Harbin in north shore of Songhua river as the research object, B-P artificial neural network is applied to build the assessment model of the eco-environmental quality. The authors take 6 factors for samples to be evaluated, the well –trained network is used to assess eco-environmental quality, The overall evaluation result being indicates that overall ecological environment mass of wetland in north shore of Songhua river is with difficulty qualified (0.6116), and by investigation and analysis, it turns out that the assessing results accord well with the actual situation, and provides the theory basis for the urban wetland healthy development. At the same time, applying artificial neural network model to wetland ecological environment quality evaluation, specifically for different ecosystem increasing network secret node or lays numbers come rise neural networks learning ability and train effect.

Abstract: Firstly, the Iridium system and SBD (Short Burst Data) service is introduced. Secondly, the marine environment monitoring system is designed based on Iridium SBD. Finally, the realization of the Iridium SBD transmission subsystem is provided. The main function of the system is to obtain the collected data by the underwater sensor. The information will be uploaded to local control center by iridium communication after fixed time. At the same time the sensor should receive commands from local control center by iridium communication.

Abstract: The smoothing parameter is a constant when forecasting water quality using exponential smoothing, which usually renders the error to be enlarged, but the assumption of constant is out of accord with the practice. Based on the deep analysis of deficiency of traditional exponential smoothing, this paper establishes self-adaptive exponential smoothing model and compares the forecast result. It is proved that the dynamic characteristic of water quality can be better reflected and the forecasting precision can be improved further by self-adaptive exponential smoothing model.

Abstract: This study aims to assess greenhouse gas (GHG) emissions of Poy(lactic acid) (PLA) with cassava starch blend (PLA/starch) and Poly(ethylene terephthalate) (PET) trays from cradle to grave. The various waste treatment scenarios were considered. The functional unit is specified as 10,000 units of 8 x 10 x 2.5 cm. of PLA/starch and PET trays which weigh 597.6 and 582.7.5 kilograms, respectively. The results from cradle to production gate were found that GHG emissions of PLA/starch has 51.38% lower than that of PET. This is because PET has higher weight of the trays. The resin production stage of PET tray has the highest of greenhouse GHG emissions. The results from cradle to grave show that the highest total GHG emissions are observed from PLA/starch or PET trays with 90% of landfill and 10% of incineration. The lowest GHG emissions from disposal PLA/starch and PET trays are from landfill with biogas recovery and incineration with heat recovery. This can be reduced GHG emissions by 3.11103 and 1.28103 kg CO2 equivalent.

Abstract: The atmospheric environmental monitoring system based on wireless sensor network is made up of embedded gateway, sensor nodes and monitoring centre. Sensor node is composed of various sensors meeting the standards for environmental monitoring, ATmega16 microcontroller as a core and ZigBee wireless communication module used to send the acquisition data to the embedded gateway which runs Linux operating system in the S3C2440A embedded microprocessor. Atmospheric environmental monitoring center receives the environmental data uploaded by the embedded gateway and stores them in the database designed with Access 2007, and provides the function as data query based on VC.

Abstract: Polycyclic aromatic hydrocarbons (PAHs) were here investigated in airborne particulate matter (PM2.5 and PM10) samples collected in urban (including residential, commercial, industrial, and traffic zones) and rural areas in and around Beijing from December 2005 to January 2006. Sixteen polycyclic aromatic hydrocarbons adsorbed onto fine- (PM2.5) and coarse- (PM10) grained samples were analyzed by gas chromatography-mass spectrometry (GC-MS). The mean total PAH concentrations were 30.1 and 80.1 ng/m3 in PM2.5, and 44.1 and 99.8 ng/m3 in PM10 in urban and rural areas, respectively. PAHs were mostly adsorbed on small inhalable particles (>50%) with four to six rings, which dominated both fractions. Strong correlations between PM-associated extractable organic matter (EOM) and particulate PAHs were found, especially in PM2.5, indicating that PM-PAHs concentrations were strongly influenced by PM-associated EOM. Of the different functional areas studied, the total PAH concentrations in both fractions were highest in industrial and rural areas and lowest in traffic zones. This may have been the result of the different emission sources and more efficient energy structures that occur during the winter. Distribution profiles and diagnostic ratios revealed that coal combustion was the major source of PM2.5- and PM10- associated PAHs. Additional sources of PAHs may include vehicle emissions, natural gas combustion and wood burning. BaP-based toxic equivalence factor (BaPeq), BaP-equivalent carcinogenic power (BaPE) and a sum of five carcinogenic PAHs showed that the industrial and rural areas were the most vulnerable to PAHs.

Abstract: To measure the carbon exchange of two different plant communities in typical steppe, we used dynamic chamber method improved from static chamber method, and compared it with the regional eddy-covariance method. Results showed that: 1) Biomass of plant community with enclosed restoration was higher than that with free grazing; 2) After 6 years enclosed restoration, the plant community had become a CO2 sink though the region was still a CO2 source while the free grazing plant community had turned into a CO2 source in contrast with its regional CO2 sink, and 3) Net ecosystem exchange (NEE) of enclosed restoration plant community was significantly higher than that of typical steppe.

Abstract: The solid-phase microextraction (SPME) technique with on-fiber derivatization coupled to gas chromatography–mass spectrometry was evaluated for the analysis of technical nonylphenol (NP) and octylphenol (OP). The optimization of operating conditions influencing the performances of SPME and derivatization were studied in detail. The optimised method was linear over the range studied and showed good level of precision, with a RSD lower than 10% and detection limits at and 0.003 μgL⁻¹ for OP and 0.032μgL⁻¹ for NP, respectively. The results obtained from different seawater samples revealed the presence of the target compounds, at levels ranging between 0.034 and 0.186 μgL⁻¹.

Abstract: A solid-phase extraction (SPE) using bamboo charcoal as absorbent coupled with constant wavelength synchronous fluorescence (CWSL) analytical method was developed for the determination of 16 polycyclic aromatic hydrocarbons (PAHs) in environmental water samples. A new method for simultaneous determination for sixteen kinds of polycyclic aromatic hydrocarbons (PAHs) in water was developed by constant wavelength synchronous fluorescence (CWSL) with bamboo charcoal solid phase extraction. The four main factors influencing on extraction efficiency, that is, type and volume of the elution solvent, sampling speed and volume were investigated. A solid-phase extraction with bamboo charcoal cartridges was carried out and the elution was performed with 15 mL of n-hexane. Sampling speed was 5 mL/min. Sampling volume was 500 mL. The linear response of this method was in the range of 0~1000ng/mL (r ≥ 0.9988), the relative standard deviations (RSDs) were in the range of 0.017%~4.12% (n = 6). The detection limits were in the range of 0.052~12.37ng /mL. .By using this method, real samples were determined directly and good results were obtained with the recoveries of 78.87%-107.9%in water from the Longjin river estuary of the provincial control section. The results showed the method was cheap, simple, and could used as an excellent alternative for the routine analysis in environmental field.

Abstract: Total hardness is one of important index to evaluate drinking water quality. The determination method of total hardness in the drinking water using the micro titration has introduced, and also has compared the obtaining results by the microburette and by the routine analysis. The relative standard deviation is far less than 2.0%. There is no obvious difference in the results. F examination and t examination are all in the appropriate scope.