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This paper describes a study of local biogenic volatile organic compounds (BVOC) emissions from the Hong Kong Special Administrative Region (HKSAR). An improved land cover and emission factor database was developed to estimate Hong Kong emissions using MEGAN, a BVOC emission model developed by Guenther et al. (2006). Field surveys of plant species composition and laboratory measurements of emission factors were combined with other data to improve existing land cover and emission factor data. The BVOC emissions from Hong Kong were calculated for 12 consecutive years from 1995 to 2006. For the year 2006, the total annual BVOC emissions were determined to be 12,400 metric tons or 9.82 × 109 g C (BVOC carbon). Isoprene emission accounts for 72%, monoterpene emissions account for 8%, and other VOCs emissions account for the remaining 20%. As expected, seasonal variation results in a higher emission in the summer and a lower emission in the winter, with emission predominantly in day time. A high emission of isoprene occurs for regions, such as Lowest Forest-NT North, dominated by broadleaf trees. The spatial variation of total BVOC is similar to the isoprene spatial variation due to its high contribution. The year to year variability in emissions due to weather was small over the twelve-year period (-1.4%, 2006 to 1995 trendline), but an increasing trend in the annual variation due to an increase in forest land cover can be observed (+7%, 2006 to 1995 trendline). The results of this study demonstrate the importance of accurate land cover inputs for biogenic emission models and indicate that land cover change should be considered for these models. © 2010 Elsevier Ltd.

Objectives: The aim of this study was to evaluate left atrial volume and its changes with the phases (active and passive) of atrial filling, and to examine the effect of normal aging on these parameters and pulmonary vein (PV) flow patterns.Background: Atrial volume change with normal aging has not been adequately described. Pulmonary vein flow patterns have not been volumetrically evaluated in normal aging. Combining atrial volumes and PV flow patterns obtained using transthoracic echocardiography could estimate shifts in left atrial mechanical function with normal aging.Methods: A total of 92 healthy subjects, divided into two groups: Group Y (young <50 years) and Group O (old > or =50 years), were prospectively studied. Maximal (Vol(max)) and minimal (Vol(min)) left atrial volumes were measured using the biplane method of discs and by three-dimensional echocardiographic reconstruction using the cubic spline interpolation algorithm. The passive filling, conduit, and active emptying volumes were also estimated. Traditional measures of atrial function, mitral peak A-wave velocity, velocity time integral (VTI), atrial emptying fraction, and atrial ejection force were measured.Results: As age increased, Vol(max), Vol(min), and total atrial contribution to left ventricle (LV) stroke volume were not significantly altered. However, the passive emptying volume was significantly higher (14.2 +/- 6.4 ml vs. 11.6 +/- 5.7 ml; p = 0.03) whereas the active emptying volume was lower (8.6 +/- 3.7 ml vs. 10.2 +/- 3.8 ml; p = 0.04) in Group Y versus Group O. Pulmonary vein flow demonstrated an increase in peak diastolic velocity (Group Y vs. Group O) with no corresponding change in diastolic VTI or systolic fraction.Conclusions: Normal aging does not increase maximum (end-systolic) atrial size. The atrium compensates for changes in LV diastolic properties by augmenting active atrial contraction. Pulmonary vein flow patterns, although diastolic dominant using peak velocity, demonstrated no volumetric change with aging. [ABSTRACT FROM AUTHOR]

Tungsten trioxide (WO 3 ) suffers from the rapid recombination of photogenerated charge carriers. For practical photoelectrochemical (PEC) water splitting, effective oxygen evolution catalysts need to be introduced to alleviate electron-hole recombination. Prussian blue analogues, with their open framework structures and adjustable metal centers, have emerged as promising candidates for oxygen evolution catalysts. This study investigates the deposition of Cobalt hexacyanoferrate (CFP) nanoparticles with different iron valence states (III and II) on terrace-like WO 3 (TW) photoanodes via a simple sequential dipping method. Notably, CFP(III) has shown to exhibit a stronger influence on photocurrent response than CFP(II). Based on Mott-Schottky studies and density functional theory calculations, CFP(III) facilitates a reduction in the depletion layer width, improves photoinduced hole kinetics, and induces steeper band bending in CFP(III)-TW, thereby enhancing PEC performance. The CFP(III)-TW photoanode achieves a photocurrent density of 1.64 mA cm -2 at 1.23 V RHE under visible light, which is 2 times and 5.4 times higher than that of TW and porous WO 3 films, respectively. Photoinduced holes with longer lifetimes suggest CFP(III)-TW experiences less surface recombination and faster separation of charge carriers compared to that of TW and CFP(II)-TW. The scalability of the CFP(III)-TW is demonstrated through the fabrication of a 25 cm 2 sheet, attaining a current of 4.6 mA at 1.23 V RHE under visible light illumination. This study highlights the straightforward synthesis of low-cost, environmentally friendly photoanode materials and establishes CFP(III)-TW as a scalable and efficient oxygen evolution catalyst for practical PEC water splitting applications. These findings underscore the potential of CFP(III) as a promising material for advancing renewable energy technologies., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2025 Elsevier Inc. All rights reserved.)

This review examines various modification techniques, including metal doping, non-metal doping, multi doping, mixed doping, and the construction of heterojunction photocatalysts, for enhancing the performance of pure TiO 2 and ZnO in the photodegradation of antibiotics. The study finds that mixed and multi doping approaches are more effective in improving photodegradation performance compared to single doping. Furthermore, the selection of suitable semiconductors for constructing heterojunction photocatalysts is crucial for achieving an efficient charge carrier separation. The environmental impacts, recent research, and real application of photocatalysis process have been discussed. The review also investigates the impact of operating parameters on the degradation pathways and the generation of by-products for different antibiotics. Additionally, the toxicity of the by-products resulting from the photodegradation of antibiotics using modified ZnO and TiO 2 photocatalysts is explored, revealing that these by-products may exhibit higher toxicity than the original antibiotics. Consequently, to enable the widespread implementation of photodegradation systems, researchers should focus on optimizing degradation systems to control the conversion pathways of by-products, developing innovative photoreactors, and evaluating toxicity in real wastewater matrices., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

The air-water interface of microbubbles represents a crucial microenvironment that can dramatically accelerate reactive oxidative species (ROS) reactions. However, the dynamic nature of microbubbles presents challenges in probing ROS behaviors at the air-water interface, limiting a comprehensive understanding of their chemistry and application. Here we develop an approach to investigate the interfacial ROS via coupling microbubbles with a Fenton-like reaction. Amphiphilic single-Co-atom catalyst (Co@SCN) is employed to efficiently transport the oxidant peroxymonosulfate (PMS) from the bulk solution to the microbubble interface. This triggers an accelerated generation of interfacial sulfate radicals (SO 4 •- ), with 20-fold higher concentration (4.48 × 10 -11 M) than the bulk SO 4 •- . Notably, the generated SO 4 •- is preferentially situated at the air-water interface due to its lowest free energy and the strong hydrogen bonding interactions with H 3 O + . Moreover, it exhibits the highest oxidation reactivity toward gaseous pollutants like toluene, with a rate constant of 10 10  M -1 s -1 -over 100 times greater than bulk reactions. This work demonstrates a promising strategy to harness the air-water interface for accelerating ROS-induced reactions, highlighting the importance of interfacial ROS and its potential application., (© 2024. The Author(s).)

Mg-ion batteries offer a safe, low-cost, and high-energy density alternative to current Li-ion batteries. However, nonaqueous Mg-ion batteries struggle with poor ionic conductivity, while aqueous batteries face a narrow electrochemical window. Our group previously developed a water-in-salt battery with an operating voltage above 2 V yet still lower than its nonaqueous counterpart because of the dominance of proton over Mg-ion insertion in the cathode. We designed a quasi-solid-state magnesium-ion battery (QSMB) that confines the hydrogen bond network for true multivalent metal ion storage. The QSMB demonstrates an energy density of 264 W·hour kg -1 , nearly five times higher than aqueous Mg-ion batteries and a voltage plateau (2.6 to 2.0 V), outperforming other Mg-ion batteries. In addition, it retains 90% of its capacity after 900 cycles at subzero temperatures (-22°C). The QSMB leverages the advantages of aqueous and nonaqueous systems, offering an innovative approach to designing high-performing Mg-ion batteries and other multivalent metal ion batteries.

The elimination of volatile organic compounds (VOCs) via vacuum ultraviolet (VUV) photolysis is greatly limited by low removal efficiency and gaseous byproducts generation, while photocatalytic oxidation of VOCs suffers from catalytic deactivation. Herein, a coupled process of gaseous VUV photolysis with aqueous photocatalytic oxidation with P25 as the catalyst was firstly proposed for efficient aromatic VOCs removal (VUV/P25). The removal efficiency of toluene reached 86.2% in VUV/P25 process, but was only 33.6% and 58.1% in alone gaseous VUV photolysis and aqueous ultraviolet photocatalytic oxidation (UV/P25) process, respectively. Correspondingly, the outlet CO 2 concentration in VUV/P25 process reached 132 ppmv. Toluene was firstly destructed by high-energy photons generated from gaseous VUV photolysis, resulting in its incomplete oxidation to form soluble intermediates including acids, aldehydes, esters. These soluble intermediates would be further degraded and mineralized into CO 2 in subsequent aqueous UV/P25 process. Notably, the concentrations of intermediates in VUV/P25 were much lower than those in VUV photolysis, indicating the synergy effect of VUV photolysis and UV/P25 process. The stability tests proved that VUV/P25 process maintained an excellent toluene degradation performance and P25 did not suffer from catalytic deactivation. In addition to toluene, the VUV/P25 system also achieved the efficient and sustainable degradation of styrene and chlorobenzene, suggesting its good application prospect in industrial VOCs treatment. This study proposes an efficient and promising strategy for deep oxidation of multiple aromatic VOCs in industries., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

A novel ohmic junction Cu@Cu 2 O photocatalyst with plasmonic enhancement had been successfully obtained by NaBH 4 reduction, which exhibited excellent photocatalytic performance for the catalytic oxidation of nitric oxide (NO) and catalytic reduction of carbon dioxide (CO 2 ). The desirable photocatalytic performance can be ascribed to the efficient interfacial charge separation and the high light absorption capacity induced by localized surface plasmon resonance (LSPR) of Cu nanoparticles in the Cu@Cu 2 O photocatalyst. To better understand why this catalyst has satisfying stability and photocatalytic performance for the removal of NO and photocatalytic reduction of CO 2 , a series of characterization methods was used to investigate the physical composition, structure, and optical properties of the sample in detail. Then, the separation efficiency of photogenerated carriers of the catalyst was investigated by time-resolved photoluminescence spectra, electrochemical impedance spectroscopy, and photocurrent density. In addition, Finite-Different-Time-Domain (FDTD) simulation and Cambridge Serial Total Energy Package (CASTEP) were adopted to confirm the Cu-induced LSPR effect, the electric field enhancement, and the band structure of the catalyst, respectively. Moreover, the ohmic junction structure has been verified by the calculation results of work function and charge density difference. Finally, a reasonable plasmonic ohmic junction photocatalytic mechanism was proposed and verified by the simulation and experiments., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Volatile organic compounds (VOCs), one of the most important gaseous air pollutants, are getting more and more attention, and a lot of technologies have been studied and applied to eliminate VOCs emissions. Advanced oxidation processes (AOPs) are considered as one of the most promising techniques used for the degradation of VOCs. Vacuum ultraviolet (VUV) catalytic oxidation system is a typical composite AOPs system involving several processes such as VUV photodegradation, photocatalytic oxidation (PCO), ozone catalytic oxidation (OZCO) and their combinations. VUV based catalytic oxidation processes have been intensively studied for degrading VOCs. This review summarizes the recent studies on the use of VUV catalytic oxidation for degrading VOCs. All the processes involved in VUV catalytic oxidation and their combinations have been reviewed. Studies of VOCs degradation by VUV catalytic oxidation can be generally divided into two aspects: developments of catalysts and mechanistic studies. Principles of different processes, strategies of catalyst development and reaction mechanism are summarized in this review. Two directions of prospective future work were also proposed., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Body sensor network is a promising medical technology to address the overwhelming global aging, which requires advanced micro power sources with high energy density, long lifetime and good biocompatibility. Potential candidates include batteries, fuel cells, energy harvesters and supercapacitors, each of which have their own merits and demerits. Batteries are currently the most mature product which has been extensively employed in the body sensor network, but the improvement of their energy density is relatively sluggish due to the cumbersome material storage. On the contrary, micro fuel cells can achieve much higher energy density because of their lightweight fuel and oxidant, which can be refueled instantly when applied in wearable sensors. For implanted devices, both abiotic and biotic fuel cells can utilize the dissolved glucose in the body fluid as fuel. As for energy harvesters, they can receive energy from both the external environment such as solar and radiofrequency, and the human body itself such as body heat and motion. Finally, supercapacitor is an effective energy storage component especially for energy harvesters, which can achieve excellent cycle stability. In general, the selection of micro power sources should consider the specific requirement from the specific sensor node, so that a body sensor network with hybrid power supply is much more reliable than that with single type of energy supply. With the continuous development of different power technologies, the body sensor network is expected to be more lightweight, unobtrusive and reliable, leading to a low-cost and ubiquitous healthcare in the near future., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Background: This study is to elucidate the disinfection effect of ozone producing low-pressure Hg vapor lamps against human pathogens. Ozone producing low-pressure Hg vapor lamps emit mainly 254 nm ultraviolet light C (UVC) with about 10% power of Vacuum-ultraviolet (VUV) light at 185 nm. The combination of UVC and VUV can inactivate airborne pathogens by disrupting the genetic materials or generation of reactive oxygen species, respectively. In this study, inactivation of common bacteria including Escherichia coli ATCC25922 (E. coli), Extended Spectrum Beta-Lactamase-producing E. coli (ESBL), Methicillin-resistant Staphylococcus aureus (MRSA) and Mycobacterium tuberculosis (MTB), and that of influenza A viruses H1N1 and H3N2 under the radiation from ozone producing low-pressure Hg vapor lamps was examined. Log reduction values at different treatment durations were determined., Methods: In vitro tests were carried out. Various bacterium and virus suspensions were added onto nitrocellulose filter papers and subjected to the illumination from ozone producing low-pressure Hg vapor lamps. The extents of pathogen inactivation at different illumination times were investigated by conducting a series of experiments with increasing duration of illumination. log10 reduction in CFU/ml and reduction at log10(TCID 50 ) were respectively measured for bacteria and viruses. The disinfection effectiveness of this type of lamps against the pathogens under the environment with a moderate barrier to light was therefore evaluated., Results: Ozone producing low-pressure Hg vapor lamp successfully inactivated these human pathogens. Nevertheless, among these pathogens, disinfection of MTB required more intense treatment. In the best tested situation, 3-log10 inactivation of pathogens can be achieved with ≤10 min of VUV treatment except MTB which needed about 20 min. This demonstrated the high resistance against UV disinfection of MTB., Conclusions: Following the criteria that valid germicidal results can be reflected with 3-log10 inactivation for bacteria, 4-log10 inactivation for viruses and 5-log10 inactivation for MTB, most of the bacteria required ≤10 min of VUV treatment, 20 min for the influenza viruses while MTB needed about 30 min VUV treatment. This indicated that VUV light is an effective approach against different environmental microorganisms.

The traditional treatment processes for volatile organic compounds (VOCs) removal generally suffered several disadvantages, such as secondary air-pollutants. To overcome these issues, wet scrubber coupled with heterogeneous UV/Fenton was developed for gaseous VOCs (i.e. toluene) removal. ZSM-5 supported iron oxide (Fe/ZSM-5) was prepared as a multifunctional catalyst for activation of H 2 O 2 and enhancement of gas-liquid mass transfer. Toluene was removed efficiently by this coupled process with the removal efficiency of 85% during 120 min. Many intermediates were detected in the solution by GC-MS while no intermediates were observed in the outlet gas, suggesting that wet scrubber coupled with heterogeneous UV/Fenton could significantly reduce secondary air pollutants. The possible mechanism of toluene oxidation was proposed including the physical adsorption by Fe/ZSM-5 and OH oxidation. This study provides an environmentally benign and highly efficient chemical scrubbing process for gaseous VOCs removal., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Due to the anthropogenic pollution, especially the environmental crisis caused by air pollutants, the development of air pollutant degradation photocatalyst has become one of the major directions to the crisis relief. Among them, titania (titanium dioxide, TiO 2 ) family materials were extensively studied in the past two decades due to their strong activity in the photocatalytic reactions. However, TiO 2 had a drawback of large bandgap which limited its applications, several modification techniques were hence developed to enhance its catalytic activity and light sensitivity. In recent years, other metal oxide based materials have been developed as replacements for TiO 2 photocatalysts. In this review, background information and developments from pure TiO 2 to chemically modified TiO 2 -based materials as photocatalysts were discussed in detail, which covered their basic properties and their role in the air pollutant removal. It also proposes to solve the shortcomings of TiO 2 by developing other metal oxide-based materials and predict the future development of TiO 2 materials in future environmental applications., (Copyright © 2019 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Ag/TiO 2 catalysts were prepared via in-situ synthesis and impregnation methods. The effect of redox state of Ag species on catalytic activity of Ag/TiO 2 catalysts was studied. The Ag-i-300 catalyst with partially oxidized state of Ag species shows superior catalytic activity, keeping HCHO removal efficiency at an extraordinary level of 100% during the 200 min's reaction. The Ag/TiO 2 catalysts were characterized by XPS, UV-Vis, BET, XRD, TEM, and in-situ DRIFTS technologies. XPS and TEM results exhibit that the partially oxidized state of Ag δ+ (0 < δ < 1) and high dispersion of Ag species are beneficial for the oxidation of HCHO over Ag/TiO 2 catalysts. According to the above results, a reaction pathway for HCHO oxidation over Ag-i-300 catalyst was also proposed., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

A novel 3-D heterojunction photocatalyst Ag 2 CO 3 /BiVO 4 was successfully fabricated. It exhibits excellent photocatalytic performances for the photocatalytic oxidation of crystal violet and reduction of Cr 6+ , which is ascribed to the suppression of charge recombination, and increasing lifetime of the charge carriers confirmed by the result of time-resolved fluorescence emission decay spectra and photoelectrochemical measures. The electron spin resonance result also suggests that heterojunction structure can improve separation efficiency of photogenerated carriers and favor to form •OH radicals. Moreover, ten intermediates and products for the photocatalytic oxidation degradation of crystal violet are identified by GC-MS., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Volatile organic compounds (VOCs) are regarded as the major contributors to air pollution, and should be strictly regulated. Photocatalytic oxidation (PCO) is of great interest for the removal of VOCs owing to its strong oxidation capability. However, its application is greatly limited by catalytic deactivation. Vacuum Ultraviolet (VUV) irradiation provides a novel way to improve the photocatalytic activity while much O 3 will be generated which may cause secondary pollution. In this study, a multi-functional catalyst of Mn/TiO 2 /activated carbon (AC) was developed to eliminate and utilize O 3 , as well as enhance catalytic oxidation of VOC degradation via ozone-assisted catalytic oxidation (OZCO). The results indicate that Mn modified TiO 2 /AC (i.e. 0.1%Mn/20%TiO 2 /AC) achieved a toluene removal efficiency of nearly 86% with 100% elimination rate of O 3 . With the help of Mn/TiO 2 /AC catalyst, O 3 was catalytically decomposed and transformed into active species of O ( 1 D) and OH, thus enhancing toluene removal. The combination of VUV irradiation with multi-functional catalyst provides a novel and efficient way for the degradation of VOCs., (Copyright © 2018 Elsevier Ltd. All rights reserved.)