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Concurrent indoor–outdoor fine particulate matter (PM2.5) measurements were conducted at urban, suburban, and rural sites in Harbin, a megacity in the northeast of China. Chemical constituents of indoor–outdoor PM2.5 were determined. Infiltration factors (FINF) of all sites were calculated according to the indoor to outdoor (I/O) ratios of PM2.5 based on the regression analysis. Linear discriminant analysis (LDA) is applied to determine the indoor–outdoor relationship. Secondary organic carbon (SOC) was calculated on the basis of organic carbon to elemental carbon (OC/EC) ratios. The mean concentrations of indoor and outdoor PM2.5 were 166.4 ± 32.5 μg/m3 and 228.4 ± 83.7 μg/m3, respectively, during the heating period. OC/EC and potassium ion to elemental carbon (K+/EC) ratios verified that biomass was an important source in Harbin especially for rural sites. The nitrate to sulfate (NO3−/SO42−) ratio indicates the higher contribution of traffic emissions in urban sites. Cr was the only species that exceeded the guidelines of WHO 2002, which was mainly emitted from coal and oil combustion. SOC/OC and NO3−/SO42− ratios, and ion-balanced acidity (the ratio of cation to anion, R+/−) showed a large urban–rural and indoor–outdoor difference. The highest SOC/OC ratio was found at urban sites, up to 38.3% for indoors. SOC/OC ratios and R+/− values of indoor environments were higher, which is attributed to the conducive condition of forming the secondary pollutants during the heating period. The results of LDA indicated that the distributions of the chemical components of PM2.5 at three sites were statistically dissimilar.

Using molecular dynamics simulations, the flexible ring polyelectrolyte chains tethered to a planar substrate and immersed in good solvents are investigated systematically. Two sets of simulations are performed to explore the effects of grafting density and charge fraction, respectively. Both the monovalent and trivalent counterions are considered. The height of the brush H follows a scaling relation with grafting density (~σgν) and charge fraction (~fν). The values of the exponents are different from those of the linear counterparts. Through a careful analysis on the distributions of monomers and counterions, pair correlation functions of monomer-monomer and monomer-counterion, as well as the fractions of trivalent counterions in four states, the equilibrium structures of the ring PE brushes are examined in detail. Furthermore, a brief comparison with the ‘equivalent’ linear brush is carried out. Also, our results can serve as a guide for improving the performance of ring polyelectrolyte brushes as unique surface modifiers.

The occurrence and fate of four cyclic (D3 to D6) and 10 linear (L5 to L14) siloxanes were investigated in influent and effluent wastewater, sludge from a wastewater treatment plant (WWTP), and surrounding air and soil within the WWTP in Harbin, Northeast China. The mean concentrations of total siloxanes in influent and effluent were 4780 and 997 ng/L and in excess sludge and aerobic sludge were 25.1 and 32.3 μg/g dw, respectively. The concentrations in air and soil within the WWTP were 243 ng/m(3) and 4960 ng/g dw, respectively. A similar composition profile of siloxanes in influent and sludge suggests their same source. Seasonal variation with concentration was comprehensively studied. It was found that temperature and rainfall are the two important factors for the seasonal variation of siloxanes. Adsorption with sewage sludge was the major way for the removal of siloxanes during the municipal wastewater treatment process. Overall, on a daily basis, the mass loading of the Σsiloxanes into the WWTP, out of the WWTP with the effluent and sludge, were estimated to be 3.0, 0.6 and 1.3 kg, respectively. In general, 21 % of siloxanes were discharged into the receiving body (Songhua River), 43 % of siloxanes were absorbed on sludge, and 36 % of siloxanes were lost during the whole process of WWTP.

Bisphenol A (BPA) is an endocrine disrupting environmental chemical. Urinary concentrations of BPA were measured in samples collected nationwide from Chinese young adults. The geometric mean urinary concentration of BPA in Chinese young adults was 2.23 ng/mL. The estimated daily exposure dose for BPA was 64.8 ng/kg bw/day. Contributions of various BPA sources to exposure in Chinese young adults were estimated. Dietary intake was the primary exposure pathway. The contribution of dietary intake, indoor dust, paper products and personal care products to BPA intake was 72.5 %, 0.74 %, 0.98 %, 0.22 % of the total exposure dose, respectively. This is the first study on the occurrence of BPA in young adults from most provinces and autonomous regions of China. The results can be used to establish a database for BPA exposure assessment for Chinese general population.

Concentrations of six phenolic endocrine-disrupting chemicals [4-tert-octylphenol (OP), 4-t-nonylphenol (4-t-NP), 4-n-nonylphenol (4-n-NP), nonylphenol mono- to di-ethoxylates (NP1EO, NP2EO), and bisphenol A (BPA)] and five estrogens [estrone (E1), β-estradiol (E2), estriol (E3) 17α-ethynylestradiol (EE2), and diethylstilbestrol (DES)] were determined in surface water and sediment samples collected from the Songhua River in northeast China. Concentrations of sum of five alkylphenols and alkylphenol ethoxylates (ΣOP, 4-n-NP, 4-t-NP, NP1EO, NP2EO) were 117–1,030 ng L−1 (mean 296) in water samples and 25.5–386 ng g−1 (mean 67.3 ng g−1 dry weight (dw)) in sediments. Concentrations of BPA in water and sediments were 8.24–263 ng L−1 (mean 52.0) and 1.60–17.3 ng g−1 dw (mean 4.90 dw), respectively. Concentrations in water were 0.840–20.8 ng L−1 (mean 5.03) for the sum of three natural steroidal estrogens (ΣE1, E2, E3) and below detection limit (BDL) at −1.38 ng L−1 (average 0.200) for the sum of two synthetic estrogens (EE2, ΣDES). Among estrogens, only E1 was detected in all of the sediment samples in the range of 0.100–3.00 ng g−1 dw. Concentrations of Σphenolic EDCs and Σestrogens in water and sediments and their correlations with total organic carbon indicated that these contaminants originate from similar sources, such as municipal wastewater. In situ $$\log K_{oc}^{\prime }$$ values and sediment–water fugacity fraction were calculated for the target chemicals, and the results indicated that these chemicals were, in general, supersaturated in sediments relative to those in water.

Dispersive liquid–liquid microextraction (DLLME) assisted with salting-out was applied for the determination of five aromatic amines in water samples by using gas chromatography with flame ionization detection. In this extraction method, several factors influencing the extraction efficiency of the target analytes, such as extraction and disperser solvent type and their volume, salt addition and amount, and pH, were studied and optimized. Under the optimal DLLME conditions, good linearity was observed in the range of 4–1,000 ng mL−1 with the RSDs from 1.2 to 7.9 %. The LODs based on S/N of 3 ranged from 0.2 to 3.4 ng mL−1 and the enrichment factors ranged from 207 to 4,315. The proposed method was successfully applied to the water samples collected from the tap and the lake, and the relative recoveries were in the range of 87.7–108.4 %.

Fourteen indoor dust samples were collected in 2010 winter from four cities in Heilongjiang Province, China. Fourteen polybrominated diphenyl ethers (PBDEs) were identified and quantified. Concentration of the total 14 PBDEs ranged from 240 to 9,270 ng/g, with the median of 2,520 ng/g. BDE209 was the dominant congener with concentrations ranged from 234 to 9,190 ng/g, accounting for 97.2 % of the total concentration. Positive correlations (r > 0.8, p

The Songhua River is the third largest river in China and the primary source of drinking and irrigation water for northeastern China. The distribution of 16 priority polycyclic aromatic hydrocarbons (PAHs) in water [dissolved water (DW) and suspended particulate matter (SPM)], sediment, and soil in the river basin was investigated, and the associated risk of cancer from these PAHs was also assessed. The total concentration of PAHs ranged from 13.9 to 161 ng L(-1) in DW, 9.21 to 83.1 ng L(-1) in SPM, 20.5 to 632 ng g(-1) dw (dry weight) in sediment, and from 30.1 to 870 ng g(-1) dw in soil. The compositional pattern of PAHs indicated that three-ring PAHs were predominant in DW and SPM samples, while four-ring PAHs dominated in sediment and soil samples. The spatial distribution of PAHs revealed some site-specific sources along the river, with principal component analysis indicating that these were from pyrogenic sources (such as coal and biomass combustion, and vehicle emissions) and coke oven emission distinguished as the main source of PAHs in the Songhua River Basin. Based on the ingestion of PAH-contaminated drinking water from the Songhua River, cancer risk was quantitatively estimated by combining the Incremental Lifetime Cancer Risk assessment model and BaP-equivalent concentration for five age groups of people (adults, teenagers, children, toddlers, and infants). Overall, the results suggest that the estimated integrated lifetime cancer risk for all groups was in acceptable levels. This study is the first attempt to provide information on the cancer risk of PAHs in drinking water from the Songhua River.

The Tibetan Plateau is suggested to be an important indicator region to study the global long-range atmospheric transport of persistent organic pollutants. In this study, atmospheric polycyclic aromatic hydrocarbons (PAHs) were studied in Lhasa City in the Tibetan Plateau, China. Air samples in gas and particle phases were concurrently collected by a modified high-volume air sampler from 5 August 2008 to 13 July 2009. The concentration of Σ16PAHs ranged from 18 to 160 ng m(-3) (with a geometric mean of 68 ng m(-3)). The most abundant PAHs were phenanthrene and benzo(b)fluoranthene in gas and particle phases, respectively. Compared with other two similar studies in Beijing and Harbin, different temporal trends were found between gas and particle phases PAHs in Lhasa. The influences of meteorological parameters (ambient temperature and relative humidity) and air masses from China, India, Southeast Asia, and West Asia were the two important reasons for explaining the difference, which was confirmed by the 5-day backward trajectories. This is the first comprehensive study to provide the evidence for the different influences of long-range atmospheric transport on gas and particle phases PAHs pollution in the Tibetan Plateau.

Mg86.33Ni13.67−x Y x (x=0, 1, 3, 6, 10) amorphous alloys were obtained by single-roller melt-spinning technique and the effect of Y addition on the glass forming ability(GFA), crystallization and micro-hardness of Mg-Ni alloys were studied. The results show that the GFA of Mg86.33Ni13.67−x Y x (x=0, 1, 3, 6, 10) is improved successfully with the Y addition. The highest GFA appeares at x=6, while the reduced glass transition temperature (T rg) is 0.5225 and the supercooled liquid region(ΔT x) is 42.06 K; the position of the main diffraction halo is different for the alloys, and the maximum of the main diffraction halo of alloys with x=0, 1, 3 corresponds to the main peaks of a metastable fcc-Mg6Ni or fcc-Mg6Ni + Ni-Y intermetallic phases, and for the alloys with x=6, 10, it corresponds to Mg-Y and Ni-Y intermetallic phases; the micro-hardness of the alloys is improved with Y additions, and the highest micro-hardness is obtained at x=6 at.%, which is 960 MPa.

The Zha Long Wetland, the first water bird conservation area in China, lies on the northern bank of the Song Nen Plain with an area of 2,100 km(2). In many areas of the Zha Long Wetland, water pollution has led to a decrease in the wetland's ecological function, vegetation degradation, a decrease in the number of bird species, and the depletion of fish resources.The sediments used in this study were collected from the surface sediment of seven sites and from different depths in three types of marshes in the Zha Long Wetland in northeast China in late October 2006. The levels and distribution patterns of 17 organochlorine pesticides (OCPs; α-HCH, β-HCH, γ-HCH, δ-HCH, p,p'-DDE, p,p'-DDD, p,p'-DDT, endosulfan I, endosulfan II, endosulfan sulfate, heptachlor, heptachlor epoxide, aldrin, dieldrin, endrin, endrin aldehyde, and methoxychlor) in surface sediments as well as hexachlorocyclohexane (HCH) and 1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane (DDT) in vertical sediments were investigated.The concentrations of HCHs, DDTs, endosulfans, heptachlors, aldrin, and methoxychlor in surface sediments ranged from 10.44 to 41.97 ng/g, nd (undetectable levels) to 211.88 ng/g, nd to 69.89 ng/g, nd to 28.10 ng/g, 9.81 to 623.83 ng/g, and from nd to 3.99 ng/g, respectively. The highest levels of OCPs were detected in Tangtugangzi at a total concentration of 727.72 ng/g, where the dominant compound was endrin at a concentration of 483.04 ng/g. In the vertical sediments, the HCHs and DDTs were in the ranges of nd-136.00 and nd-214.06 ng/g, respectively.Different distributions of HCHs, DDTs, and other OCPs indicated that they originated from different contamination sources. Composition analyses in surface sediments indicated recent OCP usage or discharge at some sample sites in the Zha Long Wetland.

Mg86.33Ni12.67Y1 amorphous alloy was obtained by a single-roller melt-spinning technique and some samples were isothermally annealed at different temperatures. The glass-forming ability (GFA), crystallization behavior and the effect of annealing treatment on the mechanical properties of the alloy were studied. The results show that for Mg86.33Ni12.67Y1 amorphous alloy, the reduced glass transformation value Trg (Trg = Tg/Tl) is 0.5089 and the width of super-cooled liquid region (ΔTx) is 40.08 K. When the samples were annealed at 413 K, the degree of short-range order of the amorphous atoms as well as the micro-hardness, increased due to structural relaxation, with increasing time, completing at 10 min. Significant crystallization of the Mg86.33Ni12.67Y1 alloy occurred after annealing above 443 K, and two crystalline phases, Mg6Ni and Ni7Y2 were precipitated into the amorphous matrix. With increasing annealing temperature (range: 573–653 K), Mg6Ni crystals were gradually transformed into Mg2Ni and α-Mg. The micro-hardness decreased significantly with temperatures above 413 K. This was accompanied by a decrease in free volume of the matrix during the crystallization of the two phases.

This paper reviews the usage and emissions of endosulfan, the newest member of the persistent organic pollutants (POPs), in China, and its fate and behavior in Chinese environment. Endosulfan usage in China has been estimated to be approximately 25700 t between 1994 and 2004. Concentrations of endosulfan in different environmental compartments in China, such as air, soil, water, and biota, but focusing at air and surface soil, have been summarized. Concentrations of total endosulfan in surface soil across China were ranged from below detection limit (BDL) to 19000 pg·g−1 dry weight (dw), with geometric mean of 120 pg·g−1dw. The results indicated that endosulfan sulfate had highest concentration in Chinese soil, followed by β- and α-endosulfan. Air concentrations of endosulfan in China were ranged 0–340 pg·m−3 for α-endosulfan and 0–121 pg·m−3 for β-endosulfan, with high concentrations occurred in the cotton production areas. Gridded usage inventories of endosulfan on a fine gridded system with a 1/4° longitude by 1/6° latitude resolution were compiled, from which, emission to air and residues in soil of endosulfan were calculated in each grid by using a modified simplified gridded pesticide emission and residue model (SGPERM), an integrated modeling system combining mathematical model, database management system, and geographic information system. Total emissions were around 10800 t from 1994 to 2004. Based on the emission and residue inventories, concentrations of α- and β-endosulfan in Chinese air and agricultural surface soil were also calculated for each grid cell, which are in general consistent with the published monitoring data.

The group velocity of light in material around the AGN jet is acquiescently one (c as a unit), but this is only a hypothesis. Here, we re-derive apparent superluminal and Doppler formulas for the general case (it is assumed that the group velocity of light in the uniform and isotropic medium around a jet (a beaming model) is not necessarily equal to one, e.g., Araudo et al. (2010) thought that there may be dense clouds around AGN jet base), and show that the group velocity of light close to one could seriously affect apparent superluminal phenomena and Doppler effect in the AGN jet (when the viewing angle and Lorentz factor take some appropriate values)., 4 pages, 2 figures, new version accepted for publication in Journal of Astrophysics and Astronomy

The spatial and seasonal variation of polychlorinated biphenyls (PCBs) were investigated in water and sediment samples collected from Songhua River, China, from 2007 to 2008. The total concentration of PCB congeners ranged from 1.1 to 14 ng/l in water and 0.26-9.7 ng/g dry weight (dw) in sediment. The results of seasonal variation may suggest an impact to PCB concentration in water from its atmospheric input, the dilution to PCBs concentrations of high stream in summer, and a general trend towards increased volatilization in warmer conditions. From PCBs concentrations comparison between upstream and downstream of industrial urban cities, it was obvious that industrial urban cities reflect an important pollutant source for PCBs in our study, also with the evidences of high concentrations of PCBs occurring in high development industry and residential areas. Meanwhile, the homologue profile of PCBs in Songhua was analyzed, whose comparison with published data indicates that the sources of PCBs accumulated in the sediment may also came from the residue of PCBs production in China. Total five dioxin-like PCBs (CB-77, 81, 105, 114, and 126) and nine (CB-77, 81, 105, 114, 118, 123, 126, 156, and 167) were found in Songhua water and sediment.

Few studies deal with teachers’ receptivity in the initiation stage of educational change, especially in a non-western cultural context like Mainland China. This study aims at investigating teachers’ receptivity to the system-wide curriculum reform of the senior secondary education in the initiation stage and understanding the factors influencing teachers’ receptivity in Mainland China. Questionnaire survey with open-ended question (n = 763) is employed to explore teachers’ receptivity in four selected experimental provinces, i.e., the first group of provinces which are selected by Ministry of Education to implement the curriculum reform. Results indicate teachers have positive attitudes and behavioral intentions toward promoting the curriculum reform of senior secondary education, and they consider the reform is valuable but difficult to carry out. The existing theoretical model can explain teachers’ behavioral intentions quite well, but its predicting ability to teachers’ general attitudes is limited, which indicates some new variables that need to be considered, too. Implications of this study and suggestions for future research are also discussed in the article.