Importance of Wintertime Anthropogenic Glyoxal and Methylglyoxal Emissions in Beijing and Implications for Secondary Organic Aerosol Formation in Megacities.

Atmospheric glyoxal (GLY) and methylglyoxal (MGLY) are key precursors of secondary organic aerosol (SOA). However, anthropogenic emissions of GLY and MGLY and their contribution to surface GLY and MGLY concentrations, as well as the secondary organic aerosol (SOA) formation, are not well quantified. By developing an emission inventory of anthropogenic GLY and MGLY and improving the Community Multiscale Air Quality Model (CMAQ) with SOA formation from irreversible surface uptake of GLY and MGLY, as well as a precursor-origin resolved technique, we quantified the source contributions of GLY and MGLY and their impact on wintertime SOA formation in Beijing, China.

Improving the regulatory health risk assessment of mercury-contaminated sites.

An alternative risk assessment strategy for mercury (Hg)-contaminated sites is proposed with bioaccessible fractions and soil Hg vapor (SHgV) concentrations. The new strategy avoids the conservatism of assessment rely on soil total Hg (THg) content and inaccuracy caused by predicted SHgV concentration. The exposure risk to Hg-contaminated soil associated with historical mining activities in Guizhou, China, was evaluated using the proposed strategy.

Carbon migration and metagenomic characteristics during anaerobic digestion of rice straw.

Background: Considerable interest has been expressed in the development of anaerobic digestion (AD) of straw to solve the environmental problems caused by the dumping and burning of straw and to generate clean energy. However, the poor biodegradability of straw and the low efficiency of energy generation achieved during its AD are problematic. Studying the parameter changes involved in the process of AD is helpful for clarifying its micro-mechanisms and providing a theoretical basis for improving its efficiency.

[Pollution Characteristics of Cooking Fumes, Particulates, and Non-methane Hydrocarbons in the Exhaust of Typical Beijing Restaurants].

To understand the atmospheric pollution emission concentration and overall emission level of the Beijing catering industry, and thus provide a basis for the targeted formulation of pollution control measures for the catering industry, this study selected typical catering enterprises in Beijing to research. Combined with the use of stoves during the on-site measurement and testing period, the emission concentrations of cooking fumes, particulates, and non-methane hydrocarbons (NMHC), and the relationship between them in different types of catering enterprises, were analyzed, and the emission of atmospheric pollutants in the Beijing catering industry was estimated. The results showed that the average concentrations of cooking fumes, particulates, and NMHC of typical catering enterprises were (2.

[Localization of Soil Wind Erosion Dust Emission Factor in Beijing].

Soil wind erosion dust is one of the primary sources of fine particulate matter (PM). Compared with the fugitive dust emission inventory of typical domestic provinces and cities, we found that the maximum among the contribution rates of soil wind erosion dust to the local total fugitive dust PM emission inventory was about 4 orders of magnitude higher than the minimum. This study provided a wind erosion equation and a determination method of parameter values.

[Emission Factors and Emission Inventory of Agricultural Machinery in Beijing Under Real-world Operation].

This study aimed to establish the emission factors and the emission inventory of agricultural machinery in Beijing in 2017 under real-world operation. The emissions of typical harvesters, tractors, agricultural transport vehicles, and farm construction machinery under real-world operation were tested by a portable emission measurement system. The results showed that different operation modes have a greater impact on the tailpipe emissions of agricultural machinery.

[Emission Characteristics of the Catering Industry in Beijing].

The emissions of the catering industry are important sources of air pollution in megacities in China. A total of 41 restaurants in Beijing were selected as the sampling sites to evaluate the contribution of the catering industry to megacity air pollution. The original emissions load of cooking fume, particulate matter, and non-methane hydrocarbon (NMHC) were studied via field tests for different types of restaurants.

[Pollution Characteristics of Volatile Organic Compounds Emission from the Metal Packaging Industry Based on Analysis of Process].

This study identified the generation and emission nodes of volatile organic compounds (VOCs) in the metal packaging industry, analyzed the VOCs concentration and species from different production processes, and accounted for secondary pollution through the maximum incremental reactivity method and modified fractional aerosol coefficient method. The results indicated that the main VOCs species were benzenes, alcohols, ketones, and esters, and the benzenes and alcohols contributed more in different types of processes and emission nodes, whereas the ketones and esters contributed less. The maximum concentration was 269.

Heavy metal pollution and human health risk assessment at mercury smelting sites in Wanshan district of Guizhou Province, China.

The Wanshan district of Guizhou Province has a long history of mercury mining and smelting. Previous studies have been carried out on heavy metal (HM) pollution in the soil around Wanshan (such as in urban and farmland areas), but these studies have not been conducted at mercury smelting sites. In this study, the distribution characteristics of As, Be, Cd, Cr, Cu, Hg, Ni, Sb, Pb and Zn and their sources in the shallow stratum (<10 m) of the mercury smelting site in the Wanshan district were analyzed.

Peculiar attenuation of soil toluene at contaminated coking sites.

In the soil of contaminated coking sites, polycyclic aromatic hydrocarbons (PAHs) and benzene, toluene, ethylbenzene and xylene (BTEX) are typical indicator compounds. Generally, PAHs are enriched in the topsoil layer. BTEX, with higher water solubilities and lower organic carbon-water partitioning coefficients (K), are distributed deeper than PAHs.

Vapor Intrusion Investigations and Decision-Making: A Critical Review.

At sites impacted by volatile organic compounds (VOCs), vapor intrusion (VI) is the pathway with the greatest potential to result in actual human exposure. Since sites with VI were first widely publicized in late 1990s, the scientific understanding of VI has evolved considerably. The VI conceptual model has been extended beyond relatively simple scenarios to include nuances, such as biological and hydrogeological factors that may limit the potential for VI and alternative pathways, such as preferential pathways and direct building contact/infiltration that may enhance VI in some cases.

Ecological criteria for zinc in Chinese soil as affected by soil properties.

The increasing accumulation of zinc (Zn) in agricultural soils has led to the need to assess the potential risk of this element for terrestrial organisms. However, the soil ecological criteria in agricultural soil as a function of soil properties have been sparsely reported. In the present study, we derived the ecological criteria (expressed as predicted no effect concentration (PNEC)) for Zn in soils, based on ecotoxicity data for 19 terrestrial species in Chinese soils, the effect of soil properties on Zn ecotoxicity, differences in species sensitivity, and differences between laboratory and realistic field conditions.

A quantitative assessment of atmospheric emissions and spatial distribution of trace elements from natural sources in China.

Natural sources, such as soil and wind-erosion dust (SWD), biomass open burning (BOB), sea salt spray (SSAS) and biogenic source (BIO), are major contributors to atmospheric emissions of trace elements (TEs) globally. In this study, we used a comprehensive approach to account for area-, production- and biofuel consumption-based emission factor calculation methods, and thus developed an integrated high-resolution emission inventory for 15 types of TEs (As, B, Cd, Co, Cr, Cu, Hg, Mn, Mo, Ni, Pb, Sb, Se, V and Zn) originated from natural sources in China for the year 2015. The results show that national emissions of TEs in 2015 range from 7.

Brilliant red X-3B uptake by a novel polycyclodextrin-modified magnetic cationic hydrogel: Performance, kinetics and mechanism.

A novel polycyclodextrin-modified magnetic cationic hydrogel (PCD-MCH) was developed and its performance, kinetics and mechanism for the removal of reactive brilliant red X-3B (X-3B) were studied. The results showed that the zeta-potential of PCD-MCH was 32.8 to 16.

[Emission Status and Standards of Volatile Organic Compounds from Chinese and Foreign Bulk Petroleum Terminals].

Chinese emission standard of air pollutants for bulk gasoline terminals (GB 20950-2007) stipulate standards for vapor emissions during gasoline storage and receiving in bulk gasoline terminals. However, the standards are not applicable to crude oil, aviation kerosene, naphtha, and other kinds of oil. We assess emission standards or directives for vapor processing equipment in terminals in the United States (US) and European Union (EU), and analyze the emission status of vapor processing equipment in three typical cities in China.

[Emission Characteristics and Ozone Formation Potential of VOCs in Printing Enterprises in Beijing-Tianjin-Hebei].

In this study, 23 typical printing enterprises were selected in Beijing-Tianjin-Hebei. Through gas chromatography-mass spectrometry/flame ionization detection (GC-MS/FID), 46 sets of analysis results were obtained to quantitatively analyze the emissions characteristics of volatile organic compounds (VOCs) and the ozone generation potential of these printing enterprises. The results show that the emission concentrations of total VOCs (TVOCs) in exhaust funnels of the printing enterprises varied greatly, ranging from 3.

[Application of Test Method for Dust Suppression Efficiency of Wind Erosion Dust Suppressant].

Wind erosion dust suppressant is an effective measure for controlling wind erosion dust. This study used the Portable In-Situ Wind Erosion Laboratory (PI-SWERL) to evaluate the efficiency of domestic and foreign dust suppressants and to compare their control efficiency of PM in terms of spraying methods, dilution factors, and wind speed. The following results were noted.

[Source Profiles of Volatile Organic Compounds (VOCs) from Typical Solvent-based Industries in Beijing].

Based on the demand for a volatile organic compounds (VOCs) emissions inventory for Beijing and for the reduction in VOC emissions, the three major solvent-based industries of automobile manufacturing, furniture manufacturing, and publication printing were selected for this study. In each case, emissions link negative pressure sampling was used in combination with laboratory-based GC-MS/FID to obtain the VOC spectra. The results show that there are significant differences in the emission of VOCs from the main stages of automobile manufacturing.

Methane production from food waste via mesophilic anaerobic digestion with ethanol pre-fermentation: Methanogenic pathway and microbial community analyses.

To investigate the methanogenic pathway and microbial community in a mesophilic anaerobic digestion (AD) system with food waste (FW) ethanol pre-fermentation (EP), two semi-continuous AD systems were operated by feeding FW with (PSR) and without EP (control). In this study, δC-ethanol was supplemented as solo substrate for AD sludge when the reactors operation stabilized to analyze the methanogenic pathways. The results suggested that approximately 59.

A green biochar/iron oxide composite for methylene blue removal.

Adsorbents that effectively remove dye substances from industrial effluents are needed for the protection of human health and the natural environment. However, adsorbent manufacture is associated with secondary environmental impacts. In this study, a green biochar/iron oxide composite was produced using a facile approach involving banana peel extract and FeSO.

Derivation of site-specific remediation goals by incorporating the bioaccessibility of polycyclic aromatic hydrocarbons with the probabilistic analysis method.

Incorporating bioaccessibility into human health risk assessment is recognized as a valid way to reduce the conservative properties of conventional results, where the total concentration of a contaminant analysed by exhaustive chemical extraction is applied. Taking a coke production site in Beijing as an example, a mild chemical extraction technology was employed to profile the bioaccessibility of benzo[a]pyrene (BaP), indeno[1,2,3-cd]pyrene (IcP) and dibenz[ah]anthracene (DBA) in soils. The results that were regressed using two bi-phase desorption models (Karickhoff and Weibull) revealed that the rapid desorption fractions of BaP, IcP and DBA, which are taken for bioaccessible fractions, were basically less than half of the total contents in the soils.

Adsorptive removal of strontium ions from aqueous solution by graphene oxide.

Graphene oxide (GO) was prepared, characterized, and applied for adsorption of Sr(II) in aqueous solution. The adsorption capacity was calculated to be 137.80 mg/g according to the Langmuir model.

Metabolic analysis of efficient methane production from food waste with ethanol pre-fermentation using carbon isotope labeling.

Anaerobic digestion (AD) has been widely applied as an economic option for food waste (FW) treatment. In this study, the group treated with ethanol pre-fermentation (EP) for 12 h (EP12) exhibited the highest cumulative biogas yield (206 mL/g-volatile solid) during AD process and therefore it was used to illuminate the underlying metabolic processes of AD with EP. Carbon isotope labeled glucose was supplemented to FW substrate, and the EP process was found to alleviate the acidification inhibition with conducting extremely high carbon flux towards ethanol formation (43.