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Long term measurements of air pollutants represented the footprints of emissions to some extent, which could provide useful and consecutive evolution of emissions. Both atmospheric concentrations and emissions of many air pollutants have been reported decreasing in the past decade due to the implement of various control measures in China, which were different for non-methane hydrocarbons (NMHCs) with increasing emissions as reported previously. The present study employed the long-term (2009–2015) NMHCs measurements as well as the related social and economic activities data in Shanghai, a megacity in eastern China, to explore the evolution of NMHCs emissions during the periods. The meteorology and photochemistry which might impact the NMHCs measurements were tested as negligible effects on an annual scale. As a result, NMHCs mixing ratio showed no statistic interannual changes, of which compositions varied significantly. This resulted a statistically decreasing trend of ozone formation potential by 3.8 % yr−1 (p −1, −6.0 % yr−1 and −7.8 % yr−1 (p −1) and petrochemical industry (−9.4 % yr−1) presented a significant decreasing trend, but the decrease slowed down in recent years; some positive reductions in solvent usage (−8.0 % yr−1) appeared after 2010; however, emissions of natural gas (+9.2 % yr−1) and fuel evaporation (with an increasing fraction) became more important. Discrepancies between measurements and emission inventory, both in interannual trend and speciation as well as source contributions, emphasized the need for further validation in NMHCs emission inventory in future. Our study confirmed the effectiveness of strengthening emission standards of vehicles and key industrial sources, generally mobile and point sources, against the increasing vehicle populations and industries in the past. While, limited reductions were observed for the fugitive emissions like petrochemical industry which need more effective measures in future. Emissions of natural gas and fuel evaporation deserved more attention as the quick increase of natural gas and fuel consumption due to the policy of energy structure reformation in China.

Chamber experiments, exhaust collection, and in-situ sampling were employed to study the emission profiles of volatile organic compounds (VOCs) from solvent use, specifically indoor paint, auto paint, furniture paint, and print ink, which are of significant importance with regard to VOC emissions in Shanghai. The results showed that there were some differences among these VOC source profiles of the emissions associated with different solvents. On the one hand, for emissions from imported indoor solvents, ~50% of the total mass concentration was contributed by aromatics, and ~30% by alkanes. On the other hand, VOC source profiles from domestic indoor paint, furniture paint, and auto paint were similar in the sense that aromatics made a much larger contribution to total VOCs, specifically, 98% for domestic indoor paint, 80%–93% for the other two, and C8–C9 aromatics accounted for ~70% of total VOCs. For VOCs from printing, C2–C5 species dominated by more than 50%, followed by C8–C9 aromatics. VOCs from the use of different solvents presented different chemical reactivities. Among the four solvents listed above, the average OH loss rate constant (k-avg) and maximum incremental reactivity (MIR-avg) of VOCs from printing were the lowest, with values of 8.2 × 10 –12 cm 3 /molecule/s and 2.9 g(O3)/g(VOC), respectively. For VOCs from painting, the average reactivity was twice that of VOCs from printing, and its value of MIR-avg was 4.7–6.3 g(O3)/g(VOC). There are significant variations in the VOC source profiles related to solvent use in different studies. The representativeness of the solvents studied and the VOC samples collected should thus be more closely examined. The accuracy of VOC source profiles related to solvent use is highly dependent on location and sampling frequency.

Background Exposure to indoor VOCs is expected to link to a variety of negative health outcome. The popularity of decorations and refurbishment in homes in China has given rise to indoor elevated VOC levels, potentially posing health threats to residents. Methods In this study, concentrations of 101 VOC compounds and associated health risks were investigated in newly renovated homes in Shanghai. The potential excess inhalation health risks from home exposure of 17 health-related VOCs were estimated by the Inhalation Unit Risk (IUR) and Reference Concentration (RfC) proposed by US EPA. Monte Carlo simulation and sensitivity analysis were used to assess the uncertainty associated with the estimates of health risks. Results The dominant groups by mass concentration were oxygenated VOCs (o-VOCs), aromatics, alkanes and halogenated VOCs (x-VOCs) .12 VOCs with IARC's confirmed or probable carcinogens ratings were detected with a > 60% detection frequency in the total samples. The mean concentrations of BTEX (benzene, toluene, m/p-xylene, o-xylene, ethylbenzene) were 2.32 μg/m3, 200.13 μg/m3, 39.56 μg/m3, 32.59 μg/m3 and 26.33 μg/m3 respectively, generally higher than those in older homes reported in previous studies except benzene. The mean concentration of methylene chloride (47.43 μg/m3) and 1,2-dichloroethane (33.83 μg/m3) were noticeably higher than the levels reported in previous studies in Hong Kong, Japan and Canada. Whereas the mean concentration of 1,4-dichlorobenzene (5.53 μg/m3) were similar to the results of Canadian national survey but lower than those in Japan. The concentrations of 1,2-dichloroethane, 1,4-dichlorobenzene, and methylene chloride, ethylbenzene presented a mean cancer risk at 7.39 × 10− 6, 1.95 × 10− 6, 1.62 × 10− 6, 1.04 × 10− 6 respectively, above the US EPA proposed acceptable risk level of 1 × 10− 6. Sensitivity analyses indicated that the VOC exposure concentration have a greater impact than the IUR values on the risk assessment. Conclusion This study highlights the characteristics of VOCs in recently renovated homes and has implications for the adverse health effects that result from exposure to chlorinated hydrocarbons in indoor air.

Sorption and degradation behaviors of atrazine were investigated with packed and intact soil columns. The measured breakthrough curves from columns were fitted with CXTFIT model program. The high mobility and long persistence of atrazine indicated by experiment results confirm that atrazine application may cause potential groundwater pollution. It was found that the obtained sorption and degradation parameters from the packed column experiments were quite similar to those obtained from the intact column experiments. These results suggest that sorption and degradation behaviors in both experiments can be used jointly to model herbicide transport at a large scale if the soil is relatively homogeneous.

We show that a protein with no intrinsic inorganic synthesis activity can be endowed with the ability to control the formation of inorganic nanostructures under thermodynamically unfavorable (nonequilibrium) conditions, reproducing a key feature of biological hard-tissue growth and assembly. The nonequilibrium synthesis of Cu(2)O nanoparticles is accomplished using an engineered derivative of the DNA-binding protein TraI in a room-temperature precursor electrolyte. The functional TraI derivative (TraIi1753::CN225) is engineered to possess a cysteine-constrained 12-residue Cu(2)O binding sequence, designated CN225, that is inserted into a permissive site in TraI. When TraIi1753::CN225 is included in the precursor electrolyte, stable Cu(2)O nanoparticles form, even though the concentrations of [Cu(+)] and [OH(-)] are at 5% of the solubility product (K(sp,Cu2O)). Negative control experiments verify that Cu(2)O formation is controlled by inclusion of the CN225 binding sequence. Transmission electron microscopy and electron diffraction reveal a core-shell structure for the nonequilibrium nanoparticles: a 2 nm Cu(2)O core is surrounded by an adsorbed protein shell. Quantitative protein adsorption studies show that the unexpected stability of Cu(2)O is imparted by the nanomolar surface binding affinity of TraIi1753::CN225 for Cu(2)O (K(d) = 1.2 x 10(-)(8) M), which provides favorable interfacial energetics (-45 kJ/mol) for the core-shell configuration. The protein shell retains the DNA-binding traits of TraI, as evidenced by the spontaneous organization of nanoparticles onto circular double-stranded DNA.

We have used the FliTrx cell surface display system to identify disulfide-constrained dodecapeptides binding to the semiconducting metal oxides Cu(2)O and ZnO. Sequence analysis of the inserts revealed that the two populations exhibit similar, yet subtly different patterns of amino acid usage. Both sets of binders were enriched in arginine, tryptophan, and glycine with a higher degree of positional preference in the case of Cu(2)O binders. Tyrosine, proline, and serine were underrepresented in both populations. Peptides binding electrodeposited Cu(2)O or ZnO with high avidity could be subdivided into two classes based on pI and hydrophilicity. In the hydrophilic and positively charged Class I binders, the Arg-X-X-Arg tetrapeptide appears to be implicated in metal oxide binding, whereas Arg-Arg and Arg-Lys pairs allow for discrimination between Cu(2)O and ZnO. Molecular dynamics simulations of the disulfide-constrained peptides suggest that the aforementioned motifs are important to properly orient two basic residues that are likely to contact the metal oxides. The implications of our results in understanding the rules governing the interaction between peptides and inorganic compounds and in their use for the design of hybrid nanoarchitectures are discussed.

Nickel hexacyanoferrate is a polynuclear inorganic ion intercalation material that loads (intercalates) and elutes (deintercalates) alkali cations from its structure when electrochemically reduced and oxidized, respectively. Nickel hexacyanoferrrate (NiHCF) is known to preferentially intercalate cesium over all other alkali cations, thus providing a basis for a separation scheme that can tackle DOE's radiocesium contamination problem. This program studied fundamental issues in alkalization intercalation and deintercalation in nickel hexacyanoferrate compounds, with the goal of (1) quantifying the ion exchange selectivity properties from cation mixtures, (2) enhancing ion exchange capacities, and (3) and understanding the electrochemically-switched ion exchange process (ESIX).