[Catalytic Combustion of Soot Particulates over Rare Earth Pyrochlore Oxides Doped with Transition Metals].

Catalytic combustion is an efficient way to remove soot particulates from automobile exhausts. A series of rare earth pyrochlore oxides La2Sn1.8TM0.2O7 (TM=Sn, Mn, Fe, Co, Cu) were prepared with CTAB-assisted sol-gel method. The products were characterized by XRD,N2 Adsorption-Desorption, SEM, FT-IR, H2-TPR and PL techniques. Their catalytic activity for soot oxidation was investigated by TPO under tight conditions in both O2 and NO+O2 atmospheres. After calcination at 900℃, the as-synthesized oxides with pure pyrochlore phase displayed nanospheres with diameter of 30-60 nm and relatively large surface areas. The partial substitution of Sn with transition metals largely influenced the reduction behavior of pyrochlores especially on the low temperature range in H2-TPR profiles, which was due to the interactions between Sn and transition metals. The improved oxygen mobility might be derived from the structure defects induced by transition metals doping, which could be helpful in oxidation reactions. In comparison with uncatalyzed reactions, the La2Sn2O7 catalyst exhibited modest catalytic activity for soot combustion, while transition metals incorporation further enhanced the activity and selectivity. The improved activity of transition metals doped samples was likely to be associated with the improved reducibility and increased surface oxygen vacancies on the pyrochlore oxides. The presence of NO in the gas phase significantly enhanced the soot oxidation activity, which was due to the promotion effect of NO2. Especially, the densities of active oxygen sites and turnover frequency (TOF) values of the catalysts, quantified by isothermal anaerobic titration with soot as a probe molecule, were used to explain the different soot combustion behaviors. Among the pyrochlore oxides, the Co-doped pyrochlore sample displayed the highest ignition activity and the largest intrinsic activity with TOF of 3.20×10-3 s-1.

[Characteristics of dioxin-like polychlorinated biphenyls contamination in soils of Gudao Region in Dongying].

To investigate pollution characteristics of dioxin-like polychlorinated biphenyls (DL-PCBs) in Gudao Region, Dongying City, twenty surface soil samples were collected in April, 2011. The DL-PCBs in soil samples were determined by Soxhelt extraction-Florisil purification-Gas Chromatography(GC)-Electron Capture Detector (ECD). The concentration of DL-PCBs in surface soils ranged from 1.4 microg x kg(-1) to 7.4 microg x kg(-1), with the mean concentration of (3.5 +/- 1.7) microg x kg(-1). The total TEQ level was between 1.2 ng x kg(-1) and 31.8 ng x kg(-1), and the mean TEQ was 5.4 ng x kg(-1), which exceeded the Canadian soil environment quality guidelines (4.0 ng x kg(-1)). The congener profiles of DL-PCBs were similar among sites. Tetra-CB and penta-CB were the major homologues in all soil samples, together accounting for more than 80% of the total DL-PCBs. The level of DL-PCBs exhibited a decreasing trend with the increasing distance from the Gudao town to the suburb, which could be attributed to the chemical plants around the town. The correlation analysis showed that the concentration of DL-PCBs was positively correlated with the organic matter content and clay particle content (R2 were 0.732 and 0.687, separately, P < 0.01), but negatively correlated with the sand particle content (R2 = -0.438, P < 0.05).

Rapid analysis of polybrominated diphenyl ethers in soil by matrix solid-phase dispersion using bamboo charcoal as dispersive sorbent.

An expeditious and sensitive method for the analysis of eight major polybrominated diphenyl ethers (PBDEs) in soil is presented in this study. The method is based on matrix solid-phase dispersion (MSPD) extraction and gas chromatography with negative chemical ionization mass spectrometry. Bamboo charcoal, a cheap and potentially useful material, was selected for the first time as the MSPD dispersive sorbent. Parameters affecting the extraction efficiency, including the ratio of sorbent to sample, and the type and amount of eluent, were investigated and optimized in detail. Under optimal conditions, the spiked recovery of the PBDEs was in the range 71.7-105.9%, and the limits of detection varied from 10 to 400 pg g(-1) (dry weight). Excellent linearity with correlation coefficients (r(2)) of 0.9992-0.9999 was obtained over the concentration range of 0.10-500 ng g(-1) , except for BDE-209, for which the effective concentration range was 1.0-5000 ng g(-1) . The developed method has been successfully applied to the analysis of PBDEs in real soil samples.

[Newly leaching method of copper from waste print circuit board using hydrochloric acid/n-butylamine/copper sulfate].

A newly leaching method of copper from waste print circuit board was established by using hydrochloric acid-n-butylamine-copper sulfate mixed solution. The conditions of leaching were optimized by changing the hydrochloric acid, n-butylamine, copper sulfate,temperature and other conditions using copper as target mimics. The results indicated that copper could be leached completely after 8 h at 50 degrees C, hydrochloric acid concentration of 1.75 mol/L, n-butylamine concentration of 0.25 mol/L, and copper sulfate mass of 0.96 g. Under the conditions, copper leaching rates in waste print circuit board samples was up to 95.31% after 9 h. It has many advantages such as better effects, low cost, mild reaction conditions, leaching solution recycling.

Isolation and characterization of a newly isolated polycyclic aromatic hydrocarbons-degrading Janibacter anophelis strain JY11.

The PAHs-degradation bacterium strain JY11 was newly isolated from the polluted soil in Jinan Oil Refinery Factory, Shandong Province of China. The isolate was identified as Janibacter anophelis with respect to its 16S rDNA sequence, DNA-DNA relatedness and fatty acid profiles, as well as various physiological characteristics. The strain was Gram-positive, non-motile, non-spore-forming, short rods in young culture, 0.8-1.0 microm in diameter and 1.3-1.6 microm long, and coccoid cells in the stationary phase of growth that are 1.0-1.2 microm in diameter and 1.3-1.5 microm long, occurred in pairs and sometimes in chains or in group, aerobic, oxidase-week positive, catalase-positive. J. anophelis strain JY11 can utilize naphthalene, phenanthrene, anthracene, pyrene, xylene, methanol, ethanol and salicylic acid as sole carbon source. The strain could remove 98.5% of phenanthrene, 82.1% of anthracene, and 97.7% of pyrene with an initial concentration of 500 ppm in five days without adding co-metabolism substrates and surfactants.

[Integration pollution index (IPI) method for evaluation of polychlorinated biphenyls (PCBs) pollution in soil].

An integration pollutant index (IPI) evaluation method with proportional addition of toxicity pollution sub-index (TPI), persistence pollution sub-index (PPI), and bio-accumulation pollution sub-indexes (BPI) for polychlorinated biphenyls (PCBs) pollution in soil was set up for the first time by referring to the conception of IPI and introducing the standard value series of total PCBs employed by national guideline and standards office, Canada. The relevant expressions for pollution indexes were defined; three transformation coefficients for PCBs toxicity (T(i)), persistence (P(i), and bio-accumulation (B(i) pollution were apportioned, too. Then, by the application of the evaluation method, the IPIs for PCBs pollution evaluations in 22 soil sample stations in the Yellow River Delta and a background sample were accomplished successfully, the quantification results were in range of 1.1-531.7, the qualification result was that the Yellow River Delta was slightly polluted by PCBs. This integrated evaluation model considered the characteristic differences between PCBs congeners and was more scientifical and comprehensive than current method, and should be employed in evaluations of persistent organic pollutants (POPs).

[Photo-catalytic degradation of gas phase benzene and toluene over multi-composite TiO2 catalyst].

Photo-catalytic degradation of gas-phase benzene and toluene were studied in the condition of no catalyst, pure anatase catalyst, pure rutile catalyst and multi-composite catalyst. The influences of initial concentration of reactants and the catalysts of different composite on photo-catalytic degradation rate of gas-phase benzene and toluene were investigated. The results show that the degradation efficiency of benzene and toluene is improved a lot on anatase catalyst, but improved a little on rutile catalyst in relation to the crystal-structure of anatase and rutile catalyst. In the condition of no catalyst and pure rutile catalyst, toluene is easier to be degradated than benzene, and on anatase catalyst benzene is easier to be done than toluene. The initial concentration of reactant has an effect on the photo-catalytic degradation process. The degradation rates of benzene and toluene are faster in low concentration than in high concentration. A certain amount of rutile doped in anatase catalyst could improve the photo-catalytic activity. The catalyst with 80% anatase and 20% rutile shows the best photo-catalytic activity to benzene, and the catalyst with 90% anatase and 10% rutile gives the best photo-catalytic activity to toluene.

Supercritical fluid extraction of quinolizidine alkaloids from Sophora flavescens Ait. and purification by high-speed counter-current chromatography.

Supercritical fluid extraction (SFE) was used to extract quinolizidine alkaloids from Sophora flavescens Ait. (Kushen). An orthogonal test L(9)(3)(4) including pressure, temperature, flow rate of CO(2) and the amount of modifier was performed to get the optimal conditions. The process was then scaled up by 30 times with a preparative SFE system under 25 MPa, 50 degrees C and a flow rate of CO(2) (2l/min) and the amount of modifier (0.04 ml/min). The crude extracts were separated and purified by high-speed counter-current chromatography (HSCCC) with a two-phase solvent system composed of chloroform-methanol-2.3 x 10(-2)M NaH(2)PO(4) (27.5:20:12.5, v/v), and the collected fractions were analyzed by high-performance liquid chromatography (HPLC). Three kinds of quinolizidine alkaloids were obtained, yielding 10.02 mg of matrine, 22.07 mg of oxysophocarpine and 79.93 mg of oxymatrine with purities of 95.6, 95.8, 99.6% in one-step separation, respectively.

[Source apportionment of dioxin-like polychlorinated biphenyls in soil of the modern Yellow River Delta].

The concentrations of 12 dioxin-like polychlorinated biphenyls (PCBs) in twenty two soil samples collected from modern Yellow River Delta were determined by dual capillary GC-ECD associated with GC-MS. Principle component analysis (PCA) was applied in analysing the dioxin-like PCBs data to obtain types, sources, percentages of source contribution and the congener composition of PCBs in the Delta on the congener level. The results indicated that four types of PCBs contamination sources affecting the PCBs distribution pattern were apportioned in the Delta. The first source was water runoff (non-point source), which was from the industrial production and use by the enterprises along the Yellow River, and it contributed 49.6% of the total contamination burden in the Delta, its dioxin-like PCBs profile was similar to native PCBs and Aroclorl221; the second and third types of PCBs sources were point sources, whose percentages of contribution were 15.0% and 10.1% respectively, the composition of the second source was similar to that of Aroclor1221 and Aroclor1242, the composition of the third source was similar to that of Aroclor1260; the fourth source is believed to be non-point source which was from the atmospheric dry and wet precipitation, it contributed 8.4%, its profile have similarity composition of the integration of Aroclor1242, Aroclor1248 and Aroclor1260.

[Ozone and carbon monoxide concentration distribution on Taishan Mountain].

The concentrations of ozone (O3) and carbon monoxide (CO) on the top of Taishan Mountain were monitored, and the variations and correlation were studied. The results show that the frequency of O3 hourly concentrations more than the first-degree of National Ambient Air Quality Standard(GB-3095-1996, NAAQS) was 15.81%, and the frequency of CO concentrations more than the first-degree of NAAQS was zero. The variation of O3 concentrations appears in a narrow scope, which indicates that there is scarcely influenced by the pollution of industry around. The diurnal variation of the concentrations of O3 and that of CO both present two peaks with the peaks of O3 in the behind of CO, which indicates that the concentration variations of O3 and its precursor CO are primarily controlled by local photochemical reaction process. The daily concentrations of O3 correlated well with CO.

[Ozone concentration distribution of urban].

The increase of ozone concentration in urban is one of the most important research topics on environmental science. With the increase of nitrogen oxides and hydrogen-carbon compounds which are exhausted from cars, the ozone concentration in urban is obviously increased on sunlight, and threat of photochemistry smog will be possible. Therefore, it is very important to monitor and study the ozone concentration distribution in urban. The frequency-distribution, diurnal variation and monthly variation of ozone concentration were studied on the campus of Shandong University during six months monitoring. The influence of solar radiation and weather conditions on ozone concentration were discussed. The frequency of ozone concentration less than 200 microg/m3 is 96.88%. The ozone concentration has an obvious diurnal variation. The ozone concentration in the afternoon is higher than in the morning and in the evening. The maximum appears in June, when it is the strong solar radiation and high air-temperature. The weather conditions also influence the ozone concentration. The ozone concentration in clear day is higher than in rainy and cloudy day.