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Taking a full-duplex (FD) technique into account, a design of cooperative cognitive radio networks (CCRN) is addressed. The FD communication in the CCRN is enabled by employing simultaneous transmitting and receiving antennas for the secondary users. From the preliminary results via numerical evaluation, it is expected that the proposed FD multiple-input-multiple-output CCRN framework can provide a performance gain over the conventional CCRN frameworks.

This paper presents a novel high temperature SOI pressure sensor utilizing Cu-Sn wafer level bonding. Fabrication process and bonding procedure are described in detail. For high temperature operation, heavily doped piezoresistors and TiSi2/Ti/ TiN/Pt/Au ohmic contact electrode are specially designed. To fabricate Cu sealing ring on the wafer with 380pm-deep cavities, spray coating method has been used to coat the wafer and define the pattern. Moreover, in order to calibrate the absolute pressure sensor at high temperatures, a novel calibration setup is designed. The measurement results show that the pressure sensor has a nonlinearity error of 0.11%FS and a sensitivity of 0.28mV/kPa with the measurement range of 30–150kPa at 300°C, which verify the reliability of the Cu-Sn wafer level bonding.

An aerobic bacterial strain Alcaligenes F-3-4 was isolated from an acrylic fiber wastewater. This strain was able to degrade 2,6-di-tert-butylphenol. The bacterium growth and 2,6-DTBP degradation was determined. Result showed, the lag period was extended when increasing the concentration of 2,6-DTBP. At 37°C and at log period, the degrading rate for 100.0 mg/L 2,6-DTBP could reach 86% within 12 d. Metabolic pathways of 2,6-DTBP degradation by Alcaligenes F-3-4 was studied. The results showed that the intermediate products are acetic acid, pyruvic acid, isobutyric acid, and so on. Identified metabolites and catabolic enzymes illustrate that the used bacterial strain attacks the benzene skeleton at the 2,3- position, and it also demethylates 2,6-DTBP. Metabolic pathways of degradation of 2,6-DTBP are proposed.

A Bio-enhanced powder activated carbon dynamic membrane reactor (BPDMR) was designed, which combined the advantages of both microbial reactor and dynamic membrane, and is a new municipal wastewater treatment technology. Based on a laboratory-scale anoxic-oxic (A/O) process, the dynamic membrane is used as the key factor of intercepting suspended solids (SS) and colloidal particles. Simultaneously, experimental results indicated that the system had the advantages of high filtration flux, low filtration resistance, easy back washing, and higher removal efficiency of the pollutants.

The aim of this study is to analisis the method of estabishing a model of A m O n integrative nutrients removal reactor, and based on the results of experiments, to optimize the operating conditions as well. The ASM mechanisms and WEST software were unilized in the model. Results showed that the relatively errors of COD, NH 3 -N, TN and TP between value of experiment and simulated are 7.2%, 9.1%, 12.5% and 6.3%, respectively. The values ranges of operating parameters are: gas/liquid ratio is between 20∶1–30∶1, and C/N is above 10∶1. A good method of simulating A m O n reactor is found and validated. The model offers a theory base which can using A m O n integrative reactor in practical more effectively.

Two kinds of biological activated carbon filter (BACF), which were immobilized by high dehydrogenase activity (DHA) bacteria isolated from river water (H-BACF) and dominant bacteria from activated sludge (S-BACF), were set up to treat the river water. Results showed that dissolved-oxygen (DO) decrease of the filtrated water (compared with the influent water), bacterium number and DHA of carbon bed in H-BACF were more than that in S-BACF, and both increased with operation time. Scanning electron microscopy (SEM) indicated there was a better effect of immobilization in H-BACF compared to S-BACF. When the influent water was chemical oxygen demand (CODMn) 3.51-4.32 mg/L, total organic carbon (TOC) 4.705-12.700 mg/L, total nitrogen (TN) 4.705-12.700 mg/L, and UV254 0.066-0.114, the removal rates of H-BACF were 65.4%, 62.5%, 35.3% and 89.5%, higher than that of S-BACF (51.2%, 54.0% , 18.9% and 87.1%). Thus, the immobilization of high DHA bacteria from object source-water could improve likely bio film activity and treatment efficiency of BACF very well.

Batch experiments were conducted to investigate the adsorption behavior of triclosan (TCS) at μg/L level in activated sludge. Effects of time, temperature, and MLSS on adsorption behavior were studied, and adsorption isotherm and thermodynamic parameters were studied as well. Sorption of TCS on the sludge was found to be physics-sorption, and partitioning played a significant role. TCS sorption process on sludge is basically exothermic and spontaneous. The study was meaningful for understanding the removal behavior of TCS in biological sewage treatment system.

Sorption experiments of triclosan (TCS) were carried out on different sludge (anaerobic, aerobic and anoxic sludge) in different type (activated sludge, sterilized sludge and antibacterial sludge). The sorption models under different temperatures (10, 20 and 30 ?) were investigated and the corresponding sorption coefficients were calculated. The results showed that TCS sorption agree with the Freundlich and Henry linear sorption model, and the coefficients Kd and KF varied with the increasing of temperature. TCS sorption show no significantly difference on activated sludge or antibacterial sludge, so the antibacterial sludge can be used in sorption experiment in stead of activated sludge. According to the validation experiment of sorption coefficients in sewage treatment system, TCS sorption on activated sludge agree with linear model, the sorption ratio on the sludge can be predicted by the linear distribution coefficient Kd.

The structural morphology and spectra characteristic of ofloxacin (OFL) was strongly affected by the pH. In strong acidic solutions, OFL molecule exists as strong cation to achieve a weaker intensity. When the pH value increased to 3-4, OFL molecule exists as zwitterions, which is the strongest fluorescence form to have maximum intensity; the maximum exciting and emission wavelength of OFL were 298 and 508 nm, respectively. Along with the increase in neutral pH value, OFL molecule exists as weak anion, fluorescence and UV spectra changed, the intensity decreased, the maximum exciting and emission wavelength of OFL were 290 and 467 nm, the UV absorbance wavelength blue-shifted 5-7 nm; under basic condition, OFL molecule exists in anion ion form, and fluorescence and UV intensity and decreases with pH increasing , but spectrum remains constant. OFL molecular spectrum is stable and achieved the maximum intensity under the pH of 3-4.

Chitosan can be a potential substitute for aluminum salts and synthetic polyelectrolytes in water treatment because it can: (1) avoid the health effects from residual aluminum (III) and synthetic polymers; (2) produce biodegradable sludge; and (3) reuse the crab shell. In this study, the chitosan flocculation characteristics in water were studied firstly, and then the combined flocculation of chitosan and inorganic flocculant is tested. The results show that the chitosan has favourable coagulation behavior. But the optimum dosage of chitosan removing turbidity and organic matter is different by using chitosan alone. However, the combined flocculation can obviously promote their each coagulant behavior and remarkably enhance the effect of organic matter removal. More importance, the optimal effect of turbidity and organic matter removal can be achieved at the same time. Comparing the effect of three inorganic coagulants combined with chitosan, the effect of chitosan combined with polymeric aluminium-ferric is best, under optimum conditions, the rate of removing turbidity, CODMn and UV254 achieved 97?, 44? and 55? respectively. And whether chitosan combining with inorganic flocculation or not, on the best conditions, the residual aluminum concentration is less than the examination methods limit in effluent water.

A procedure for the determination of synthetic musks compounds (Galaxolide (HHCB), Tonalide (AHTN), musk xylene (MX) and musk ketone (MK)) in water samples was described. Analytes were extracted from the samples using solid phase extraction (SPE) system on ENVI-C18 cartridges and then determined by gas chromatography-mass spectrometry (GC-MS). Influence of five experimental parameters (volume of eluent, composition ratio of eluent, flow rate during eluted process, methanol content in washed solution and pH of water samples) on the recovery efficiency of the SPE procedure was systematically studied using a U9(9 5 ) quasi-level uniform design at three levels. Four mathematical models were obtained from nine experiments. The optimized results were in order of 12 ml, 67 % n-hexane, 0.5 ml/min, 10 % methanol, pH 6.0. Under optimal extraction conditions, recoveries from 72.15% to 90.46% were obtained for spiked water samples with relative errors from 0.80% to 9.21%.

Hydrothermal treatment of glycerin was carried out at 300degC by using eight base catalysts, including hydroxides of alkali metals, alkaline-earth metals and aluminum. All selected catalysts promoted the conversion of glycerin into lactic acid, except for Al(OH) 3 . The alkali-metal hydroxides were found to be more effective than alkaline-earth-metal hydroxides on hydrothermal conversion of glycerin. In the case of NaOH or KOH, a lactic acid yield of approximate 90% can be approached. Moreover, KOH was superior to NaOH on promoting the hydrothermal conversion of glycerin. Ba(OH) 2 and Sr(OH) 2 was found to convert glycerin further into formic and acetic acids. A decomposition mechanism of lactic acid with Ba(OH) 2 was proposed.

As fungicides or preservatives in pharmaceutical and personal care products (PPCPs), triclosan (TCS) is widespread in the environment. Under low concentration, the toxicity of triclosan is not obvious, but under certain conditions, it can be converted into other substances, whose toxicity has already caused concerns. A method for analysis of tricosan in water using solid phase extraction (SPE) and high performance liquid chromatography(HPLC) with Ultra-Violet(UV) detection was developed. Conditions of gradient elution and HPLC separation of the toxicant were also optimized. Detection limit of the method was found to be 3.91 ng/L. Relative standard deviation(RSD) was around 2.02 ~ 4.69%. The average recovery of triclosan was around 93.68~97.42%. With this method, water samples of three wastewater treatment plants in Shanghai were detected. Results showed that the concentration of triclosan ranged from 533 ng/L to 774 ng/L in raw wastewater samples and from 80.14 ng/L to 249.72 ng/L in the effluent samples. The removal efficiencies of the entire processes ranged from 62.59% to 67.74%.

Heavy metals, a kind of persistent toxic substance (PTS), were taken for the study in this paper. Dust samples (44 in total) were collected in 2006 in Shanghai urban parks. The concentrations of Cu, Pb and Zn in dusts were determined by atomic absorption spectrometer. The concentrations of mean metals in dust samples were in the order Zn > Pb > Cu, where Pb shows the greatest coefficient of variation. The concentrations of heavy metals in dust samples exceeded soil background values of Shanghai. According to the exposure models for heavy metal pollutants, human health risk was evaluated in Shanghai urban parks. Compared with the Netherlandish allowable level of human ingested toxic pollutants, the exposure dose of lead for children is nearly doubled in deposited dust in Shanghai urban parks. The pathway of direct ingestion is dominating for children exposed to PTS, which is more than 98% of the overall exposure dose, followed by the pathway of dermal contact and inhalation. It shows that the pathway of direct ingestion is the principal pathway for children exposed to PTS in deposited dust in Shanghai urban parks and the health risk of PTS for children should not be overlooked. Through statistical analysis of arcgis module, the corresponding distributions of Cu, Pb and Zn show an increasing trend towards inner ring road. By contrast with roadside dust samples, collected near the upper reaches of the Huangpu River, which was viewed as a region with less man-made pollution, the main sources of these elements in Shanghai urban parks were mainly derived from human activities, especially for traffic sources.

In this study, we developed a mathematical model based on anaerobic digestion model No.1 (ADM1) for municipal wastewater treatment. The model classified the microbes in an anaerobic system as two genera: acidogens and methanogens. According to their growth and decay processes, the model simplified the anaerobic digestion of municipal wastewater into two sub-processes: transforming sugar, protein and lipid into VFA and then producing CH 4 and CO 2 from VFA. Also, chemical equilibriums were introduced. The dynamic process involved in the anaerobic system was solved by Matlab to calculate the effluent quality of the reactor such as COD, the VFA concentration, pH, and alkalinity variation. Based upon the ADM1 and dynamic constants in the literature, the stable operational data obtained from a pilot reactor was used for parameter sensitivity analysis, estimation, adjustment and calibration of the anaerobic digestion dynamic model. The dynamic model was then used to simulate the performance of the same OCAR reactor under the condition of an upward flow velocity of 2.0, 3.67, 5.0, 7.0, and 10.3 m/h as well as the residence time of 6, 4, 2, and 1 h during 165 days. The average relative error of estimated effluent COD, alkalinity, VFA is less than 10% as compared with the actual operation results.

In this paper, the occurrence and removal of eight fluoroquinolone antibiotics were investigated at a sewage treatment plant (STP) in Shanghai, China. The most frequently detected fluoroquinolone antibiotics in the present study were norfloxacin, ciprofloxacin and lomefloxacin. The concentrations of these compounds in water samples at the STP ranged from 103 to 1786 ng L -1 , 14 to 1406 ng L -1 and 21 to 2246 ng L -1 , respectively. The other fluoroquinolone antibiotics were detected only in a few samples from the STP. FQs in aquatic phase could not be eliminated completely from the STP, with the removal efficiencies from 70% to 100%. The concentrations of FQs in water detected in summer were higher than in other seasons, due to the more desorption from sludge to aquatic phase under higher temperature.

The most effective way for removing fluorine in desulfurization waste water of power plants was discussed in this paper on the basis of various fluoride removal methods. The chemical precipitation + coagulation (+ flocculation) method was recommended .The results indicated that the feasible precipitant and coagulation reagent were Ca(OH)2 and Al2(SO4)3, the optimal Ca/F and Al/F were 1:1.5 and 3:2, respectively. Further experiment was carried out with an assistant flocculant polyacrylamide (0.1%) and the optimal VPAM was studied. Many experimental results revealed: this removing fluoride system can reduce the fluorine concentration from 140-200 mg/L to 10 mg/L below in waste water, according with the industrial waste water discharge standards in our country. The method to treat fluoride waste water was operated conveniently and low-cost, and it can be generalized widely in power plants.

In the study, we focus on the water quality monitoring and mapping using remote sensing .The objective of the research is to develop a precise and fast way of monitoring water chemical and biochemical quality of the water resources reservation area in the upper region of Huangpu River in Shanghai, China. One scene Thematic Mapper (TM) image in summer of 2005 was acquired and the simultaneous in situ measurement, sampling and analysis were performed. The main methods include radiometric calibration of TM remote sensor, atmospheric correction to image data and statistical model construction. The results indicate that satellite-based estimates and in situ measured water reflectance have high correlation, and a statistical relationship between calibrated image data (average of 5 times 5 pixels) of TM bands and laboratory analyzed data of water samples indicated that the reflectance of TM band 1 to band 4 and organic pollution measurements such as BOD and COD had higher correlation.