Simulation of engine faults and their impact on emissions and vehicle performance for a liquefied petroleum gas taxi.

The deterioration of emissions control systems in a spark ignition engine is predominantly a gradual process of wear and tear occurring as vehicles accumulate mileage. As new innovations in engine and emissions technology have been progressively introduced to meet lower emissions targets, the impact of gradual deterioration of hardware has become more challenging to identify and quantify in the repair industry. When a pioneering emissions control programme utilising remote sensing to detect high emitting gasoline and liquefied petroleum gas (LPG) vehicles was to be introduced in Hong Kong, it became apparent the repair industry needed specialised training to assist with identifying the types of failures which would lead to high vehicle emissions.

Large eddy simulation of vehicle emissions dispersion: Implications for on-road remote sensing measurements.

On-road remote sensing technology measures the concentration ratios of pollutants over CO in the exhaust plume in half a second when a vehicle passes by a measurement site, providing a rapid, non-intrusive and economic tool for vehicle emissions monitoring and control. A key assumption in such measurement is that the emission ratios are constant for a given plume. However, there is a lack of study on this assumption, whose validity could be affected by a number of factors, especially the engine operating conditions and turbulence.

Improving street walkability: Biometeorological assessment of artificial-partial shade structures in summer sunny conditions.

Recent rapid urbanization has rendered outdoor space a key quality-of-life factor, yet walkability studies especially in hot-humid climates have seldom considered human biometeorology. This site-level study investigated microclimatic functions of an overhead structure in improving walkability, and identified biometeorology-related factors influencing pedestrian behaviour. A walkway with overhead tinted glass cover, demarcated into sunny zone and shaded zone, was equipped with hanging aluminium fins.

Potential role of Candida albicans secreted aspartic protease 9 in serum induced-hyphal formation and interaction with oral epithelial cells.

Introduction: Candida albicans possesses the ability to switch rapidly between yeast to hyphal forms. Hyphal formation is a remarkable pathogenic characteristic, which allows C. albicans to invade into host cells.

A review on high catalytic efficiency of solid acid catalysts for lignin valorization.

It is imminent to develop renewable resources to replace fossil-derived energies as fossil resources are on the brink of exhaustion. Lignin is one of the major components of lignocellulosic biomass, which is a natural amorphous three-dimensional polymer with abundant C-O bonds and aromatic structure. Hence, valorization of lignin into high value-added liquid fuels and chemicals is regarded as a promising strategy to mitigate fossil resource shortages.

Tuning the Acidity of Pt/ CNTs Catalysts for Hydrodeoxygenation of Diphenyl Ether.

We herein present a method for the synthesis of HNbWO6, HNbMoO6, HTaWO6 solid acid nanosheet modified Pt/CNTs. By varying the weight of various solid acid nanosheets, a series of Pt/xHMNO6/CNTs with different solid acid compositions (x = 5, 20 wt%; M = Nb, Ta; N = Mo, W) have been prepared by carbon nanotube pretreatment, protonic exchange, solid acid exfoliation, aggregation and finally Pt particles impregnation. The Pt/xHMNO6/CNTs are characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy and NH3-temperature programmed desorption.

Effects of using four baskets during simulated youth basketball games.

This study aimed to identify how playing basketball with two additional baskets influences the players' technical, physiological, physical and especially, positional performance. Fourteen youth players performed eight 5vs.5 simulated basketball games, four with the two official baskets and four with two-extra official baskets, each one placed in the court restricted area.

Recent advancement in lignin biorefinery: With special focus on enzymatic degradation and valorization.

With the intensive development of lignocellulosic biorefineries to produce fuels and chemicals from biomass-derived carbohydrates, lignin was generated at a large quantity every year. Therefore, lignin has received increasing attention as an abundant aromatics resource in terms of research and development efforts for value-added chemicals production. In this review, studies about lignin degradation especially the crucial enzymes involved and the reaction mechanism were substantially discussed, which provided the molecular basis of lignin biodegradation.

Tree distribution, morphology and modelled air pollution in urban parks of Hong Kong.

Trees offer a range of ecosystem services and remain important in providing human benefits. However, emerging literature questions the long-accepted view of trees being able to improve air quality in urban parks. The aerodynamic effect of trees was identified as a major reason for the change of pollutant distribution in near-road parks, where trees can act as porous barriers and cause localised concentration increase.

Generation and Reactivity of a One-Electron-Oxidized Manganese(V) Imido Complex with a Tetraamido Macrocyclic Ligand.

The synthesis and X-ray structure of a new manganese(V) mesitylimido complex with a tetraamido macrocyclic ligand (TAML), [Mn (TAML)(N-Mes)] (1), are reported. Compound 1 is oxidized by [(p-BrC H ) N] [SbCl ] and the resulting Mn species readily undergoes H-atom transfer and nitrene transfer reactions.

Microbial characterization of heavy metal resistant bacterial strains isolated from an electroplating wastewater treatment plant.

Heavy metal pollution is one of the most widespread and complex environmental issues globally, posing a great threat to the ecosystem as well as human health. Bioremediation through heavy metal-resistant bacteria (HMRB) is currently the most promising technology to address this issue. To obtain HMRB to remediate heavy metal pollution potentially, 15 culturable HMRB strains were isolated from the sludge samples of an electroplating wastewater treatment plant (EWWTP), which belonged to the Bacillus, Shewanella, Lysinibacillus, and Acinetobacter genera.

Characterisation of diesel vehicle emissions and determination of remote sensing cutpoints for diesel high-emitters.

Diesel vehicles are a major source of air pollutants in cities and have caused significant health risks to the public globally. This study used both on-road remote sensing and transient chassis dynamometer to characterise emissions of diesel light goods vehicles. A large sample size of 183 diesel vans were tested on a transient chassis dynamometer to evaluate the emission levels of in-service diesel vehicles and to determine a set of remote sensing cutpoints for diesel high-emitters.

Effects of Different Intraset Rest Durations on Lifting Performance and Self-perceived Exertion During Bench Press Exercise.

Ho, IMK, Luk, JTC, Ngo, JK, and Wong, DP. Effects of different intraset rest durations on lifting performance and self-perceived exertion during bench press exercise. J Strength Cond Res 35(8): 2114-2120, 2021-This study compared the number of successful repetitions, failure rates, and ratings of perceived exertion (RPEs) among intraset rest (ISR) protocols (0-, 20-, or 40-second rest between third and fourth repetitions) during bench press exercise with total 3 sets and 6 repetitions per set at 6 repetition maximum (6RM) load.

Integrated photocatalytic-biological treatment of triazine-containing pollutants.

The degradation of triazine-containing pollutants including simazine, Irgarol 1051 and Reactive Brilliant Red K-2G (K-2G) by photocatalytic treatment was investigated. The effects of titanium dioxide (TiO) concentration, initial pH of reaction mixture, irradiation time and ultraviolet (UV) intensity on photocatalytic treatment efficiency were examined. Complete decolorization of K-2G was observed at 60 min photodegradation while only 15 min were required to completely degrade simazine and Irgarol 1051 under respective optimized conditions.

Synthesis of Sea Urchin-Like NiCoO via Charge-Driven Self-Assembly Strategy for High-Performance Lithium-Ion Batteries.

In this study, hydrothermal synthesis of sea urchin-like NiCoO was successfully demonstrated by a versatile charge-driven self-assembly strategy using positively charged poly(diallydimethylammonium chloride) (PDDA) molecules. Physical characterizations implied that sea urchin-like microspheres of ~ 2.5 μm in size were formed by self-assembly of numerous nanoneedles with a typical dimension of ~ 100 nm in diameter.

Fuel consumption and emissions performance under real driving: Comparison between hybrid and conventional vehicles.

Hybrid electric vehicles (HEVs) are perceived to be more energy efficient and less polluting than conventional internal combustion engine (ICE) vehicles. However, increasing evidence has shown that real-driving emissions (RDE) could be much higher than laboratory type approval limits and the advantages of HEVs over their conventional ICE counterparts under real-driving conditions have not been studied extensively. Therefore, this study was conducted to evaluate the real-driving fuel consumption and pollutant emissions performance of HEVs against their conventional ICE counterparts.

Mechanism of Water Oxidation by Ferrate(VI) at pH 7-9.

The kinetics of water oxidation by K FeO has been reinvestigated by UV/Vis spectrophotometry from pH 7-9 in 0.2 m phosphate buffer. The rate of reaction was found to be second-order in both [FeO ] and [H ].

A comprehensive review of anaerobic digestion of organic solid wastes in relation to microbial community and enhancement process.

Organic solid wastes (OSWs) should be regarded as valuable resources rather than dead-end landfill waste that causes public health and odor concerns. Anaerobic digestion (AD) is an ideal approach for managing organic solid waste issues and involves using a group of anaerobic microorganisms to transform OSWs into useful products. In this review, over 100 publications related to AD of OSWs have been compiled, discussed, and analyzed.

Physical Activity and Physical Fitness of Adults with Intellectual Disabilities in Group Homes in Hong Kong.

Adults with intellectual disabilities (ID) typically have a sedentary lifestyle and higher rates of overweight and obesity. This study describes the habitual daily physical activity (PA) and the health-related physical fitness (PF) of adults with mild and moderate ID who resided in four group homes and worked in sheltered workshops. We also assessed the contribution of PF variables towards PA levels and sedentary behavior of this population subgroup.

Effect of polysaccharide chain conformation on ultrasonic degradation of curdlan in alkaline solution.

This study was to investigate the effects of polysaccharide chain conformation on ultrasonic degradation of curdlan, a high MW β-glucan with wide applications. The ultrasonic degradation was performed in alkaline solution at 0.1 M and 0.

A modified method of high molecular weight adsorbable organic chlorine measurement in saline water: Dialysis pretreatment.

Adsorbable organic halogen is a mean to quantify total organic halogen, which is an important toxicity indicator in disinfection byproduct studies. However, quantification of low concentrations of adsorbable organic chlorine (AOCl) formation in seawater chlorination using the USEPA Method 9020B was found inaccurate due to the presence of high concentrations of chloride. In this study, a dialysis-based pretreatment technique was proposed, optimized and adopted to eliminate the interference of chloride in quantifying low concentrations of AOCl in seawater.

Sorption, mobility, and bioavailability of PBDEs in the agricultural soils: Roles of co-existing metals, dissolved organic matter, and fertilizers.

Polybrominated diphenyl ethers (PBDEs) are common pollutants released from electronic waste (e-waste) dismantling and recycling activities. Our city-wide survey of agricultural soils in Qingyuan (40 sampling sites), where e-waste recycling has been active, observed exceedance of PBDEs above background levels (average of 251.9ngg, 87 times the regional baseline concentration) together with elevated levels of metals/metalloids at the contamination hotspots, such as As (180.

Reduction of Ru≡N to Ru-NH by Cysteine in Aqueous Solution.

The reduction of metal nitride to ammonia is a key step in biological and chemical nitrogen fixation. We report herein the facile reduction of a ruthenium(VI) nitrido complex [(L)Ru(N)(OH)] (1, L = N, N'-bis(salicylidene)- o-cyclohexyldiamine dianion) to [(L)Ru(NH)(OH)] by l-cysteine (Cys), an ubiquitous biological reductant, in aqueous solution. At pH 1.

Phosphorus speciation in sewage sludge and the sludge-derived biochar by a combination of experimental methods and theoretical simulation.

Sewage sludge is an inevitable byproduct from municipal wastewater treatment processes and conversion of sewage sludge into high value-added biochar is an effective strategy for resource utilization of sewage sludge. The characterization on P speciation is important to control the practical applications and environmental behavior of the sewage sludge and its derived biochar. The mobility and bioavailability of P is closely related to its speciation, but knowledge gap in P speciation is still existed which needs to be narrowed by a systematic study including existing experimental methods and techniques as well as theoretical prediction.

Combined application of EDDS and EDTA for removal of potentially toxic elements under multiple soil washing schemes.

Chelant-enhanced soil washing, such as EDTA (ethylenediaminetetraacetic acid) and biodegradable EDDS ([S,S]-ethylene-diamine-disuccinic acid), has been widely studied, however, EDTA is persistent under natural conditions while EDDS has a low efficiency for Pb extraction. Therefore, we investigated the efficacy of mixed chelants (EDDS and EDTA mixture at 1:1 M ratio) for the removal of Cu, Zn, and Pb from a field-contaminated soil using various washing schemes (multi-pulse, step-gradient chelant, and continuous washing schemes). Speciation modelling of the target metals, mineral elements, and EDDS/EDTA was performed, while the leachability and bioaccessibility of residual metals in the treated soils were also assessed.