Temporal and spatial variations of air pollution across China from 2015 to 2018.

This study investigated concentrations of PM2.5, PM10, SO2, NO2, CO and O3, and air quality index (AQI) values across 368 cities in mainland China during 2015-2018. The study further examined relationships of air pollution status with local industrial capacities and vehicle possessions. Strong correlations were found between industrial capacities (coal, pig iron, crude steel and rolled steel) and air pollution levels. Although statistical and significant reductions of PM2.5, PM10, SO2, NO2, CO and AQI values were observed in response to various laws and regulations in industrial sectors, both particle and gaseous pollutants still had annual average concentrations above recommended limits. In order to further reduce air pollution, more efforts can be done to control traffic emissions caused by minicars and heavy trucks, which was revealed after investigating 16 vehicle types. This was also consistent with the apparent air quality improvement during the COVID-19 lockdown period in China in 2020, despite industrial operations being still active at full capacities.

Pyrolysis of heavy metal contaminated biomass pre-treated with ferric salts: Product characterisation and heavy metal deportment.

The metal(loid)-enriched Avicennia marina biomass obtained from phytoremediation was impregnated with two ferric salts (FeCl3 and Fe(NO3)3) prior to pyrolysis at 300-700 °C, aiming to study the influence on pyrolytic product properties and heavy metal(loid) deportment. Results showed that the impregnated ferric salts increased the fixed carbon content of biochars, hydrocarbon fractions in bio-oils, and the evolution of CO and H2 in gases. Cd in biomass could be effectively removed from the biomass by FeCl3 impregnation. During pyrolysis, the ferric salts enhanced the elemental recovery of As, Cr, Ni and Pb in the biochars and decreased their distribution in gases. Notably, the ferric salt pre-treatment inhibited the mobility and bio-availability of most elements in the biochars. This study indicated that ferric salt impregnation catalysed the pyrolysis process of metal(loid) contaminated biomass, enabled the operation temperature at 500-700 °C with minimal environmental risks, providing a safe and value-added way to the phytoremediation-pyrolysis scheme.

Contamination identification, source apportionment and health risk assessment of trace elements at different fractions of atmospheric particles at iron and steelmaking areas in China.

China has the largest share of global iron and steel production, which is considered to play a significant contribution to air pollution. This study aims to investigate trace element contamination at different fractions of particulate matter (PM) at industrial areas in China. Three PM fractions, PM2.1-9.0, PM1.1-2.1 and PM1.1, were collected from areas surrounding iron and steelmaking plants at Kunming, Wuhan, Nanjing and Ningbo in China. Multiple trace elements and their bioavailability, as well as Pb isotopic compositions, were analysed for identification of contaminants, health risk assessment and source apportionment. Results showed that PM particles in the sites near industrial areas were associated with a range of toxic trace elements, specifically As, Cr(VI), Cd and Mn, and posed significant health risks to humans. The isotopic Pb compositions identified that coal and high temperature metallurgical processes in the steelmaking process were the dominant contributors to local air pollution in these sites. In addition to iron and steelmaking activities, traffic emissions and remote pollution also played a contributing role in PM contamination, confirmed by the differences of Pb isotopic compositions at each PM fraction and statistical results from Preference Ranking Organization Method for Enrichment Evaluations (PROMETHEE) and Geometrical Analysis for Interactive Aid (GAIA). The results presented in this study provide a comprehensive understanding of PM emissions at iron and steelmaking areas, which helps to guide subsequent updates of air pollution control guidelines to efficiently minimise environmental footprint and ensure long term sustainability of the industries.

Characterization of size resolved atmospheric particles in the vicinity of iron and steelmaking industries in China.

China currently faces environmental challenges of lower air quality, partly as a result of industrial activities. The aim of this study was to investigate the role of iron and steelmaking facilities to regional air quality in four selected industry dominated urban centres in China. Nine different particle size ranges present in atmospheric particles collected from four sites in Kunming (KM), Wuhan (WH), Nanjing (NJ) and Ningbo (NB) were analysed and compared with particles collected at one background site at the Ningbo Nottingham University (UN) with very little industrial influence in China. Similar mass concentration levels of particulate matter PM2.1 and PM1.1 were found at the three sites near older iron and steelmaking plants (KM, WH and NJ). Significantly lower levels of PM2.1 and PM1.1 were collected at the fourth site (NB), which is near to a modern and coastal iron and steelmaking plant. The particles collected had the highest mass concentration in the aerodynamic diameter range of 3.3-9.0 µm for all sites, except for the background site (UN). Scanning electron microscopy equipped with energy-dispersive X-ray spectroscopy, and inductively coupled plasma were used to determine the surface morphology and particle chemistry. Al, Ca, Fe, K, Mg, Na and Zn were found as the most abundant elements in all samples. The enrichment factors show that elements As, Cd, Cr, Cu, Pb and Zn were significantly enriched in particles, especially in fine particles, posing an adverse impact on human health. This study can be used to assist the development of particle monitoring programmes in the vicinity of industrial areas and also help to establish an elemental modality dataset on the exposure and risk assessments of atmospheric particles.

Effect of temperature on heavy metal(loid) deportment during pyrolysis of Avicennia marina biomass obtained from phytoremediation.

Slow pyrolysis of heavy-metal(loid)-contaminated Avicennia marina biomass obtained from phytoremediation was conducted to investigate the deportment of 12 heavy metal(loid)s in pyrolysis products (biochar, bio-oil, gas) at temperatures from 300 to 800 °C. The results indicated that different heavy metal(loid)s showed diverse volatilities, while all elements tended to transform into volatile products with the increase of pyrolysis temperature. Cd was found highly volatile, while Fe and Cu were non-volatile elements. The leaching analysis of biochars showed that pyrolysis was effective in reducing the mobility and bioavailability of the heavy metal(loid)s in biochars. Moreover, the risk assessment of biochars showed that the biochars derived from polluted biomass can be used as a potential soil amendment. Considering the energy consumption and risk of contaminant emission, pyrolysis temperatures of 400 to 500 °C were considered to be the optimum option for pyrolysis of this biomass.

Interrelationship of microplastic pollution in sediments and oysters in a seaport environment of the eastern coast of Australia.

Since the middle of the twentieth century, microplastics have emerged as a pollutant of concern. Sea ports are recipients of large amount of discharges through ballast water, ship traffic and other commercial activities, which may additionally add to the overall marine microplastic pollution. The aim of this study was to determine the interrelationship of microplastic pollution in the sediments and oysters at six major seaports (Port Jackson, Botany, Kembla, Newcastle, Yamba and Eden) of New South Wales (NSW). The results revealed the significant abundance of microplastic particles both in sediments and oysters in all the studied seaports which were estimated to be around 83-350 particles/kg dry weight in the sediments and 0.15-0.83 particles/g wet weight in the oysters. Although, the abundance of microplastics showed similar pattern in the sediments and oysters of the studied seaports, oysters had higher number of microplastics than sediments in all sea ports. Moreover, the results showed that the shapes, size and colours in the oysters did not necessarily match the main components in the sediments, although the polymer types matched well between each other. Black fibres between 0.1mm-0.5mm in size were the most abundant microplastics in oysters, whereas white spherules between 0.5mm-1mm in size were dominant in the sediments of NSW seaports. Moreover, the analysis of variance between microplastic abundance in sediment and oysters showed a non-significant positive linear relationship. Fourier Transform Infrared analysis further indicated that both sediments and oysters contained microplastics with two main polymers, polyethylene terephthalate and nylon, which suggests that the abundance of microplastics in the study ports was highly influenced by the port activities, mainly the intensive commercial fishing and fish processing activities along with intensive anthropogenic and industrial activities inside and surroundings the port environments.

Bio-oil upgrading with catalytic pyrolysis of biomass using Copper/zeolite-Nickel/zeolite and Copper-Nickel/zeolite catalysts.

The bio-oil obtained from a general pyrolysis process contains a higher concentration of oxygenated compounds and the resultant physical and chemical properties make it an unsuitable drop-in fuel. The oxygenated compounds in the bio-oil can be converted into hydrocarbons or less oxygenated compounds with the application of catalysts. This study demonstrated the bio-oil upgrading with the application of catalysts, comparing the catalytic effect of combined mono-metallic catalysts (Cu/zeolite and Ni/zeolite) and sole bi-metallic catalyst (CuNi/zeolite) on the composition of bio-oil and pyrolytic gases. The results demonstrated that in comparison to the combined mono-metallic catalysts, the sole bi-metallic catalyst showed better deoxygenation for all the oxygenated compounds and favoured the production of aliphatic hydrocarbons, whereas the combination of mono-metallic catalysts generated higher proportion of aromatic hydrocarbons in the bio-oil. In both cases, the catalysts equally favoured decarboxylation and decarbonylation reactions, as CO2/CO of approximately 1 was obtained during the pyrolysis process.

Clinical trial requests of indigenous diagnostic imaging ultrasound devices in first-time registration application / 中国医疗器械杂志

This article introduces the clinical requests of indigenous diagnostic imaging ultrasound devices in first-time registration application and the clinical trial requests in Technical Review Guidance of Ultrasound Imaging Diagnostic Devices (category III) Registration and puts forward some questions of the guidance's implementation. It is hoped to help concerned people.