Advanced Materials Research Vols. 356-360

Abstract: In order to investigate the intermolecular hydrogen bonding of special amphiphiles, two bolaform amphiphilic Schiff bases (GN1 and GN2) with different hydrophilic spacers were designed, and their interaction with barbituric acid were tested by liquid chromatography. The chromatographic properties showed that both the Schiff bases showed hydrogen bonding interaction with barbituric acid. In addition, the influence of various detectors was also studied on both cases. Experimental results show that the test with FLD showed better determination than other detectors. It is proposed that due to the directionality and strong matching of hydrogen bond, one barbituric acid molecule can be encapsulated into the intramolecular area of GN1, while two barbituric acid molecules were trapped into the GN2 molecule through intermolecular H-bonds for GN2 due to the long spacer and flexible structure. A rational complex mode was proposed.

Abstract: The competitive absorption and desorption of cadmium (Cd), lead (Pb) and zinc (Zn) in meadow brown soil from Liaoning province in north-east China was studied in the paper in order to establish the selectivity sequences for the sorption and desorption of these heavy metals in the soil and obtain the absorption and desorption dynamic character of these heavy metals. The results showed that with the increasing of the absorption times, the absorption quantities of Cd, Pb and Zn were increased little by little. The absorption process of Cd, Pb and Zn could be divided into the fast absorption phase and the slow absorption phase. And the fast absorption phases were from the beginning to 60 min, 120 min and 120 min for Cd, Pb and Zn, respectively. The more company metals (i.e. Pb and Zn) existed in the absorption solutions, the less absorption quantities of Cd absorbed by soil. The co-existence of Cd, Pb and Zn had obviously decreased the absorption of Pb by soil. And it was the same situation that Zn absorbed by soil was decreased by the company metals such as Cd, Pb. The company metals had obvious influence on the desorption process of Cd. The existence of Pb and Zn promoted the desorption of Cd. And desorption behavior of Zn was bated by the existence of Pb and Cd. While the company metals Cd and Zn restrained the desorption of Pb. The best equation to describe the absorption and desorption dynamic character of Cd, Pb and Zn was Elovich equation, next was Two–constant equation, and the effect of First-order dynamics equation was not good.

Abstract: The subject of the paper is to study the effect of the different river habitat on biological diversity of microalgae in order to reveal the status of algae indicators in the evaluation of river ecosystem health. The study is conducted to compare planktonic algae and epilithic algae in Shendinghe rive (SR) and Qihe river (QR) of Danjiangkou reservoir in August 2010. The trophic status is evaluated by saprobic system. There are 193 species (varieties) belonging to 98 genera and 7 phylums of planktonic algae and 61 species (varieties) belonging to 36 genera and 3 phylums of epilithic algae in the samples of SR. There exist 165 species (varieties) belonging to 82 genera and 7 phylums of planktonic algae and 48 species (varieties) belonging to 10 genera and 4 phylums of epilithic algae in the samples of QR. 15 genera instructions 21 species (varieties) of saprobic indicators are identified in the monitored rivers. The number of oligonucleotide indicators in QR is higher than that in SR, and the number of eutrophication indicators in QR is lower than that in SR. The water quality of QR is Biologically superior to that of SR.

Abstract: In order to use the Cd-contaminated saline soil, experiments have been carried out to analyze the differences among effects of three salts on cadmium accumulation capacities of Brassica Napus in Cd-contaminated soil, thus to figure out the phytoremediation effects of planting Brassica Napus in different types of Cd-contaminated saline soils. Brassica Napus(a cadmium hyperaccumulator plant) has been as the research plant, the Brassica Napus was planted in Cd-contaminated soils (Cd: 10 mg•kg-1) with different salt concentrations(0 g•kg^-1, 2g•kg^-1,4 g•kg^-1 and 6 g•kg^-1) for 60 days as required by the greenhouse pot soil culture experiment, thus to study the bioconcentration factor(BCF) of Brassica Napus on Cd and the effects of Brassica Napus on the changes of concentrations in the shoots and roots. The three main salts in the soil, namely, sodium chloride, sodium sulfate and sodium carbonate, were chosen as the analysis and research objects. The results showed that the soil containing sodium carbonate inhibited the Brassica Napus from absorbing Cd in the soil, so did the soil containing sodium sulfate, however, the effect was not so obvious as that of the soil containing sodium carbonate. However, the soil containing sodium chloride had little impact on Cd absorption of the Brassica Napus that it could only slightly promote the cadmium accumulation capacities of Brassica Napus under a very high concentration, In different types of saline soils, there were significant differences among the effects of different salts on cadmium accumulation capacities of Brassica Napus, the sodium chloride in the soil had little impact on cadmium accumulation capacities of the roots of Brassica Napus, however, it could enhance the cadmium accumulation capacities of the shoots of Brassica Napus; the sodium carbonate in the soil could significantly inhibit the shoots and roots of Brassica Napus from accumulating the cadmium, therefore, it was not conducive for the Brassica Napus to accumulate cadmium.

Abstract: The composite of copper ion and cypermethrin (CPM) may affect the hydrolysis of CPM. The experiments considered different factors which may affect the hydrolysis of pesticides, using buffer solutions with different pH to study the hydrolysis of CPM. The results showed that the existence of Cu²⁺ significantly promoted the hydrolysis of CPM, which might be related to the complexes that Cu²⁺ and CPM had produced. The hydrolysis kinetics of CPM followed the first-order kinetics. We used GC/MS to detect the hydrolysis of CPM intermediates and proposed the possible hydrolysis pathways.

Abstract: Dual end and single end MacroRAFT agents of polystyrene were obtained respectively by polymerizations of styrene in the presence of benzyl 1H-imidazole-1- carbodithioate (BICDT) and 4,4‘-bis(imidazole-1-carbodithioatemethyl)biphenyl (ICTMP) via the thermal initiation. Then copolymerization of allyl glycidyl ether（AGE） with methyl acrylate（MA） was performed to prepare the functional block copolymers in the presence of PSt maeorRATF agents. The results show that the process has good characteristics of living free radical polymerization. However, the top monomer conversion of triblock copolymers comparing diblock copolymers is lower under the same theory molecular weight and the content of monomer.

Abstract: Cold rolling wastewater is very difficult for treatment with high oil content, complex composition, toxicity and other characteristics. In the conventional treatment process, the most widely used methods are ultrafiltration(UF), gas-energy-management(GEM) and membrane bioreactor(MBR). In this study, we used the biological fluidized bed to treat the cold rolling wastewater, which made the bioaugmentation apply to anaerobic biofilter and biological fluidized bed (BF-BFB) combined process, and the optimal process parameters were determined. The contents of COD and NH4+-N were 3276.8mg/L and 67.65mg/L in inflow water, and after treatment, they were reduced to 108.8mg/L and 6.36mg/L, respectively. The removal rates of COD and NH4⁺-N were 96.68% and 91.01%.

Abstract: Polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) are a group of important persistent organic pollutants. Quantitative structure–property relationship (QSPR) modeling is a powerful approach for predicting the properties of environmental organic pollutants from their structure descriptors. In this study, a QSPR model is established for estimating n-octanol/water partition coefficient (log KOW) of PCDD/Fs. Three-dimensional holographic vector of atomic interaction field (3D-HoVAIF) is used to describe the chemical structures, SMR-PLS QSAR model has been created and good correlation coefficients and cross-validated correlation coefficient is obtained. Predictive capability of the models has also been demonstrated by leave-one-out cross-validation. Moreover, the estimated values have been presented for those PCDD/Fs which are lack of experimentally data by the optimum model.

Abstract: Polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) are a group of important persistent organic pollutants. In the present study, three-dimensional holographic vector of atomic interaction field (3D-HoVAIF) is used to describe the chemical structures of PCDD/Fs. After variable screening by stepwise multiple regression (SMR) technique, the liner relationships between solid vapor pressure (logPS) of PCDD/Fs and 3D-HoVAIF descriptors by partial least square (PLS) regression.The result shows that the 3D-HoVAIF descriptors can be well used to express the quantitative structure-property relationships of PCDD/Fs. Predictive capability of the models has also been demonstrated by leave-one-out cross-validation. Moreover, the estimated values have been presented for those PCDD/Fs which are lack of experimentally data by the optimum model.

Abstract: A quantitative structure property relationship (QSPR) model is established for estimating aqueous solubility (log SW) of PCDD/Fs. Three-dimensional holographic vector of atomic interaction field (3D-HoVAIF) is used to describe the chemical structures, the correlation between the 3D-HoVAIF descriptors of PCDD/Fs and aqueous solubility (log SW) was established by partial least square (PLS) regression. The predictive power of the model was validated by leave-one-out cross-validated analysis. Moreover, the estimated values have been presented for those PCDD/Fs which are lack of experimentally data by the optimum model.