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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]

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).)

Heterogeneous electrode materials possess abundant heterointerfaces with a localized "space charge effect", which enhances capacity output and accelerates mass/charge transfer dynamics in energy storage devices (ESDs). These promising features open new possibilities for demanding applications such as electric vehicles, grid energy storage, and portable electronics. However, the fundamental principles and working mechanisms that govern heterointerfaces are not yet fully understood, impeding the rational design of electrode materials. In this study, the heterointerface evolution during charging and discharging process as well as the intricate interaction between heterointerfaces and charge/mass transport phenomena, is systematically discussed. Guidelines along with feasible strategies for engineering structural heterointerfaces to address specific challenges encountered in various application scenarios, are also provided. This review offers innovative solutions for the development of heterogeneous electrode materials, enabling more efficient energy storage beyond conventional electrochemistry. Furthermore, it provides fresh insights into the advancement of clean energy conversion and storage technologies. This review contributes to the knowledge and understanding of heterointerfaces, paving the way for the design and optimization of next-generation energy storage materials for a sustainable future., (© 2024 The Author(s). Advanced Materials published by Wiley‐VCH GmbH.)

In recent years, there have been significant advancements in Al-ion battery development, resulting in high voltage and capacity. Traditionally, only carbon-based materials with layered structures and strong bonding capabilities can deliver superior performance. However, most other materials exhibited low discharge voltages of 1.4 V, especially in aqueous Al-ion battery systems lacking anion intercalation. Thus, the development of high-voltage cathode materials has become crucial. This study introduces 2D MoS 2 as a high-performance cathode for aqueous Al-ion batteries. The material's interlayer structure enables the intercalation of AlCl 4 - anions, resulting in high-voltage intercalation. The resulting battery achieved a high voltage of 1.8 V with a capacity of 750 mAh g -1 , contributing to a high energy density of 890 Wh kg -1 and an impressive retention rate of ≈100% after 200 cycles. This research not only sheds light on the high-voltage anion-intercalation mechanism of MoS 2 but also paves the way for the further development of advanced cathode materials in the field of Al-ion batteries. By demonstrating the potential of using 2D MoS 2 as a cathode material, this finding can lead to the development of more efficient and innovative energy storage technologies, ultimately contributing to a sustainable and green energy future., (© 2023 The Authors. Small Methods published by Wiley‐VCH GmbH.)

Metal-organic frameworks (MOFs) are high-performance adsorbents for atmospheric water harvesting but have poor water-desorption ability, requiring excess energy input to release the trapped water. Addressing this issue, a Janus-structured adsorbent with functional asymmetry is presented. The material exhibits contrasting functionalities on either face - a hygroscopic face interfaced with a photothermal face. Hygroscopic aluminum fumarate MOF and photothermal Cu x S layers are in-situ grown on opposite sides of a Cu/Al bimetallic substrate, resulting in a Cu x S-Cu/Al-MOF Janus hygro-photothermal hybrid. The two faces serve as independent "factories" for photothermal conversion and water adsorption-desorption respectively, while the interfacing bimetallic layer serves as a "heat conveyor belt" between them. Due to the high porosity and hydrophilicity of the MOF, the hybrid exhibits a water-adsorption capacity of 0.161 g g -1 and a fast adsorption rate (saturation within 52 min) at 30% relative humidity. Thanks to the photothermal Cu x S, the hybrid can reach 71.5 °C under 1 Sun in 20 min and desorb 97% adsorbed water in 40 min, exhibiting a high photothermal conversion efficiency of over 90%. Cu x S-Cu/Al-MOF exhibits minimal fluctuations after 200 cycles, and its water-generation capacity is 3.21 times that of powdery MOF in 3 h in a self-designed prototype in one cycle., (© 2024 The Authors. Small published by Wiley‐VCH GmbH.)

Vacuum ultraviolet (VUV) photolysis is a facile method for volatile organic compounds (VOCs) elimination, but is greatly limited by the relatively low removal efficiency and the possible secondary pollution. To overcome above drawbacks, we developed an efficient method for VOCs elimination via VUV photolysis coupled with wet scrubbing process. In this coupled process, volatile toluene, a representative of VOCs, was oxidized by the gas-phase VUV photolysis, and then scrubbed into water for further oxidation by the liquid-phase VUV photolysis. More than 96% of toluene was efficiently removed by this coupled process, which was 2 times higher than that in the gas-phase VUV photolysis. This improvement was attributed to the synergistic effect between gas-phase and liquid-phase VUV photolysis. O 3 and HO • are the predomination reactive species for the toluene degradation in this coupled process, and the generation of O 3 in gas-phase VUV photolysis can efficiently enhance the HO • production in liquid-phase VUV photolysis. The result from in-situ proton transfer reaction ionization with mass analyzer (PTR-MS) further suggested that most intermediates were trapped by the wet scrubbing process and efficiently oxidized by the liquid-phase VUV photolysis, showing a high performance for controlling the secondary pollution. Furthermore, the result of stability test and the reuse of solution demonstrated that this coupled process has a highly stable and sustainable performance for toluene degradation. This study presents an environmentally benign and highly efficient VUV photolysis for gaseous VOCs removal in the wet scrubbing process., (Copyright © 2022. Published by Elsevier B.V.)

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.

Photocatalysis is regarded as one of the most promising technologies for indoor volatile organic compounds (VOCs) elimination due to its low cost, safe operation, energy efficiency, and high mineralization efficiency under ambient conditions. However, the practical applications of this technology are limited, despite considerable research efforts in recent decades. Until now, most of the works were carried out in the laboratory and focused on exploring new catalytic materials. Only a few works involved the immobilization of catalysts and the design of reactors for practical applications. Therefore, this review systematically summarizes the research and development on photocatalytic oxidation (PCO) of VOCs, with emphasis on recent catalyst's immobilization and reactor designs in detail. First, different types of photocatalytic materials and the mechanisms for PCO of VOCs are briefly discussed. Then, both the catalyst's immobilization techniques and reactor designs are reviewed in detail. Finally, the existing challenges and future perspectives for PCO of VOCs are proposed. This work aims to provide updated information and research inspirations for the commercialization of this technology in the future.

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.)

Urea-rich wastewater can cause serious eutrophication problem to the water environment. On the other hand, urea is a potential fuel with high energy density, which can be effectively utilized by direct urea fuel cell. In this work, exfoliated graphite (EG) with high surface area and electrical conductivity was obtained by microwave irradiation, which was used to support the Ni-Fe layered double hydroxide (LDH), leading to a highly efficient and low-cost urea oxidation catalyst. Compared with commercial RuO 2 , the as-prepared Ni-Fe LDH/EG exhibited a lower onset potential of 1.25 V vs. reversible hydrogen electrode as well as a lower Tafel slope of 44 mV dec -1 . The catalyst durability was also proved to be excellent. The optimized Ni/Fe molar ratio was confirmed to be 3 : 1, while the most suitable catalyst/EG ratio was 3 : 50. When applied in a dual-electrolyte direct urea fuel cell, the peak power density reached 12 mW cm -2 , and the long-term discharge was also stable with negligible voltage loss at 10 mA cm -2 for 3 h. Such a low-cost and efficient urea oxidation catalyst can be widely utilized in future direct urea fuel cells, which achieve wastewater treatment and renewable electricity generation at the same time., (© 2022 Wiley-VCH GmbH.)

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.)

VOCs abatement has attracted increasing interest because of the detrimental effects on both atmospheric environment and human beings of VOCs. The assistance of ozone has enabled efficient VOCs removal at low temperature. Thereby, catalytic ozonation is considered as one of the most feasible and effective methods for VOCs elimination. This work systematically reviews the emerging advances of catalytic ozonation of different VOCs (i.e., aromatic hydrocarbons, oxygenated VOCs, chlorinated VOCs, sulfur-containing VOCs, and saturated alkanes) over various functional catalysts. General reaction mechanism of catalytic ozonation including both Langmuir-Hinshelwood and Mars-van-Krevelen mechanisms was proposed depending on the reactive oxygen species involving the reactions. The influence of reaction conditions (water vapor and temperature) is fully discussed. This review also introduces the enhanced VOCs oxidation via catalytic ozonation in the ozone-generating systems including plasma and vacuum ultraviolet. Lastly, the existing challenges of VOCs catalytic ozonation are presented, and the perspective of this technology is envisioned., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Aqueous Al-ion battery (AAIB) is regarded as a promising candidate for large-scale energy storage systems due to its high capacity, high safety, and low cost, with MnO 2 proved to be a high-performance cathode. However, the potential commercial application of this type of battery is plagued by the frequent structural collapse of MnO 2 . Herein, an in situ, electrochemically reformed, urchin-like Al x MnO 2 cathode is developed for water-in-salt electrolyte-based AAIBs. Benefiting from its unique α-MnO 2 coated Mn 2 AlO 4 structure, a high Al ion storage capacity is achieved together with a high discharge voltage plateau of 1.9 V by reversible MnO 2 electrolysis. Consequently, the battery exhibits a high specific capacity of 285 mAh g -1 and a high energy density of 370 Wh kg -1 at a high current density of 500 mA g -1 . Improved stability with record capacity retention is also obtained at an ultrahigh current density of 5 A g -1 after 500 cycles. Such a high-capacity and high-stability Al x MnO 2 cathode would pave the way for in situ electrochemical transformation of cathode design and thus boost the practical application of AAIBs., (© 2021 Wiley-VCH GmbH.)

Au/g-C 3 N 4 /Co 3 O 4 plasmonic heterojunction photocatalyst was successfully prepared by in-situ forming Co 3 O 4 nanocubes on the Au/g-C 3 N 4 nanosheets. The catalytic activities of the photocatalysts were systematically studied through the catalytic reduction of hexavalent chromium (Cr 6+ ) and oxidation of Bisphenol A (BPA) under visible light irradiation, while according to the degradation products determined by GC-MS, the catalytic degradation pathway of BPA was proposed. 4Au/g-C 3 N 4 /Co 3 O 4 sample exhibits the most efficient catalytic activities, and the photocatalytic reduction and photocatalytic oxidation efficiencies can obtain 85.6% and 90.3%, respectively. The main reasons of the enhancing catalytic performance are the high absorption capability to visible light generated by localized surface plasmon resonance and the effective interface charge separation. Finally, we speculated that the Au/g-C 3 N 4 /Co 3 O 4 sample followed Z-scheme charge transfer mechanism in this study, which is verified by the analysis of experiment and theoretical calculation results., (Copyright © 2020. Published by Elsevier B.V.)

An efficient Z-scheme Co 3 O 4 /g-C 3 N 4 heterojunction photocatalyst was developed via in-situ forming Co 3 O 4 nanocubes on the g-C 3 N 4 nanosheet in the hydrothermal process. The obtained photocatalyst exhibited high photocatalytic activity for the visible-light-driven catalytic reduction of Cr(VI) and catalytic oxidation of tetracycline (TC). Among the as-synthesized catalysts, Co 3 O 4 /g-C 3 N 4 -0.04 (the mass ratio of g-C 3 N 4 to Co 3 O 4 is 0.04) sample exhibits the most efficient catalytic activities. The photocatalytic reduction and photocatalytic oxidation efficiencies of Co 3 O 4 /g-C 3 N 4 -0.04 can obtain 81.3 and 92.6 %, respectively. Moreover, the TC is mineralized in the course of photocatalytic degradation, 72.2% of TOC is removed from the reaction system. In addition, the apparent quantum efficiency for the removal of Cr(VI) was also obtained and the the Co 3 O 4 /g-C 3 N 4 -0.04 could achieve the highest apparent quantum efficiency among the samples. The enhancing photocatalytic activities originated from the efficient interfacial charge migration and separation obtained in Co 3 O 4 /g-C 3 N 4 -0.04, which is preliminarily confirmed by the photoluminescence spectra, time-resolved photoluminescence spectra and the photoelectrochemical characterizations. Finally, we speculate that the Co 3 O 4 /g-C 3 N 4 heterostructures follow a more reasonable Z-scheme charge transfer in this study, which is confirmed by analyzing the results of electron paramagnetic resonance, radical scavenging experiments, and theoretical calculations., (Copyright © 2020 Elsevier B.V. All rights reserved.)

A novel 2D/3D Z-scheme g-C 3 N 4 /SnS 2 photocatalyst was successfully fabricated via self-assembly forming 3D flower-like SnS 2 microspheres on the surface of the 2D g-C 3 N 4 nanosheets. The photocatalytic performances of the samples were systematically explored through catalytic reduction of Cr 6+ and oxidation of Bisphenol S (BPS) under the illumination of visible light, and the photocatalytic degradation pathway of BPS was also proposed based on the degradation products confirmed by GCMS. Among the as-prepared samples, 0.4-g-C 3 N 4 /SnS 2 exhibited the most efficient photocatalytic performances, and the apparent quantum efficiency (QE) for the removal of Cr 6+ could achieve 30.3 %, which is 2.8 times higher than that of the SnS 2 . The enhancing photocatalytic activities originated from the efficient interfacial charge migration and separation obtained in g-C 3 N 4 /SnS 2 , which was firstly verified via the photoluminescence spectra, time-resolved photoluminescence spectra and photoelectrochemical characterizations. Importantly, the DFT calculated shows that the band distribution of the g-C 3 N 4 /SnS 2 sample is staggered near the forbidden, which can facilitate the efficient interfacial charge migration and separation as well as result in the improvement of the catalytic activity. Finally, we put forward a more reasonable Z-scheme charge transfer mechanism, it was verified by analysing the results of free radical scavenging tests, EPR experiments and theoretical calculations., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Volatile organic compounds (VOCs) exists ubiquitously in chemical industries and were regarded as major contributors to air pollution, which should be strictly regulated. Vacuum ultraviolet irradiation coupled with photocatalytic oxidation (VUV-PCO) has been considered as an efficient approach to VOCs removal due to high-energy photons which could break down VOCs directly and be absorbed by photocatalysts to generate free radicals for further oxidation. However, the photochemical transformation mechanisms of VOCs have not been fully revealed. Herein, we systematically analyzed the intermediates using proton-transfer-reaction mass spectrometer (PTR-MS) to explore the transformation mechanisms of toluene degradation in VUV and VUV-PCO processes. VUV-PCO process displayed superior toluene degradation efficiency (50 %) and mineralization efficiency (65 %) compared with single VUV photolysis (35 %) and UV photocatalysis (5 %). TiO 2 was deeply involved into CO 2 generalization by amplifying the advantages of VUV system and further mineralizing the intermediates. In VUV and VUV-PCO processes, O 2 participation changed the intermediates distribution by increasing multiple oxygenated products, while the introduction of water contributed to the formation and degradation of most intermediates. A possible degradation mechanism of toluene under VUV irradiation combined with TiO 2 was proposed. This study provides a deep mechanistic insight into VOCs degradation by VUV-PCO process., (Copyright © 2020 Elsevier B.V. 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.)

Volatile organic compounds (VOCs) are one of the most important precursors to form the fine particulate matter and photochemical smog, and should be strictly controlled. Vacuum ultraviolet (VUV) photolysis has provided a facile and an effective way to remove VOCs due to its powerful oxidation capability under mild reaction conditions. However, VUV irradiation would generate ozone which brings about secondary pollution. In this study, ZSM-5 supported Mn-Ce mixed oxides (Mn-xCe/ZSM-5) were fabricated as efficient catalysts for ozone catalytic oxidation (OZCO) process, which were applied in combination with VUV photolysis to remove O 3 byproduct and simultaneously facilitate toluene oxidation. The results indicated that the Mn-3Ce/ZSM-5 catalyst considerably enhanced the catalytic degradation efficiency up to 93% for the gas-phase toluene, one of the hazardous VOCs. Meanwhile, almost all the O 3 by-product could be eliminated in the process. It was found that the strong interaction of the MnOCe bond and the variable chemical valence of Mn and Ce based species in the mixed oxides would tune the redox capacity of Mn-xCe /ZSM-5. An increase in surface Ce 3+ species and surface density of oxygen vacancies would benefit the adsorption and catalytic transformation of O 3 which eventually form the reactive oxygen species over Mn-xCe/ZSM-5., (Copyright © 2018 Elsevier B.V. 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.)

In this study, Ag deposited three-dimensional MnO 2 porous hollow microspheres (Ag/MnO 2 PHMSs) with high dispersion of the atom level Ag species are first prepared by a novel method of redox precipitation. Due to the highly efficient utilization of downsized Ag nanoparticles, the optimal 0.3% Ag/MnO 2 PHMSs can completely degrade 70 ppm CH 3 SH within 600 s, much higher than that of MnO 2 PHMSs (79%). Additionally, the catalyst retains long-term stability and can be regenerated to its initial activity through regeneration with ethanol and HCl. The results of characterization of Ag/MnO 2 PHMSs and catalytic performance tests clearly demonstrate that the proper amount of Ag incorporation not only facilitates the chemi-adsorption but also induces more formation of vacancy oxygen (O v ) and lattice oxygen (O L ) in MnO 2 as well as Ag species as activation sites to collectively favor the catalytic ozonation of CH 3 SH. Ag/MnO 2 PHMSs can efficiently transform CH 3 SH into CH 3 SAg/CH 3 S-SCH 3 and then oxidize them into SO 4 2- and CO 2 as evidenced by in situ diffuse reflectance infrared Fourier transform spectroscopy. Meanwhile, electron paramagnetic resonance and scavenger tests indicate that •OH and 1 O 2 are the primary reactive species rather than surface atomic oxygen species contributing to CH 3 SH removal over Ag/MnO 2 PHMSs. This work presents an efficient catalyst of single atom Ag incorporated MnO 2 PHMSs to control air pollution.

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.)

This work demonstrates the use of a NiCu electrocatalyst prepared by hydrothermal method with different Ni/Cu mass ratios (70:30, 50:50 and 30:70) supported on carbon nanotubes (CNTs), which was studied with regards to its electrochemical behavior in the ammonia oxidation reaction and direct ammonia microfluidic fuel cell (DAMFC) performance. XRD and SEM-EDX showed the formation of NiCu alloy while TEM showed the particles size to be 15-20 nm. Cyclic voltammetry and chronoamperometry showed that NiCu had higher catalytic activity than pure Ni and pure Cu, and that the active species was a NiCu oxyhydroxide. In DAMFC tests, 50 wt % Ni 50 Cu 50 /CNTs was found to be the most suitable one since it showed a 43 % higher peak power density and 65 % higher maximum current density than Ni electrode. The improved performance was attributed to the NiCu oxyhydroxides formation, which improved the anodic catalytic activity by increasing amounts of active sites and the combined electronic effect of the Ni-Cu bimetallic catalysts., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The process of vacuum ultraviolet (VUV)-assisted photocatalytic oxidation (PCO) has attracted great interest for volatile organic compounds (VOCs) degradation owing to its strong oxidation capability. However, the O 3 by-product from VUV irradiation causes secondary pollution and needs to be overcome. In this study, a multi-functional photocatalyst of Mn/g-C 3 N 4 /ZSM-4 was thus developed by a one-pot hydrothermal method, and then combined with VUV irradiation to eliminate O 3 byproduct as well as enhance toluene degradation via ozone-assisted catalytic oxidation (OZCO). Under VUV irradiation alone, 64% of toluene degradation was occurred but 51 ppm of O 3 was residual. In contrast, toluene degradation was enhanced to 96% over the Mn/g-C 3 N 4 /ZSM-4 while residual O 3 was decreased to 4 ppm. The enhanced performance was attributed to the synergistic PCO and OZCO, as the Mn modification can efficiently enhance the photocatalytic activity of g-C 3 N 4 and trigger the catalytic ozonation simultaneously. The results of electron spin resonance (ESR) confirmed the generation of reactive species such as OH and O 2 - by VUV irradiation and then greatly enhanced after Mn/g-C 3 N 4 /ZSM-4 was added. Moreover, the possible mechanism of toluene degradation was also revealed through monitoring of reaction intermediate. Obviously, the process of Mn/g-C 3 N 4 /ZSM-4 cooperated well with VUV is promising for VOCs degradation., (Copyright © 2018 Elsevier B.V. All rights reserved.)

The thermogravimetric (TG) experiments of cattle manure were carried out from room temperature to 900°C at five different heating rates (10, 20, 30, 40 and 50°C/min) and the kinetics of the main decomposition process were analyzed with different methods. TG curves indicate that the major decomposition process of cattle manure could be roughly divided into three stages. The average activation energy of each stage calculated by Coats-Redfern method are 68.95, 2.63 and 55.32kJ/mol respectively. The kinetic parameters given by Distributed Activation Energy Model method, Flynn-Wall-Ozawa method and Vyazovkin method are all show that the activation energies keep stable (at around 122.4, 126 and 123.8kJ/mol respectively) under 60% conversion degree and then changed dramatically (ranging from 129.9 to 454.9kJ/mol). Power law (P3) was determined as an appropriate reaction mechanism using master-plots method. The kinetic parameters calculated by Vyazovkin method can give the best agreement with the experimental results., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Background: Detectable levels of high sensitivity (cardiac) troponin T (HsTnT), occur in the majority of patients with stable coronary heart disease (CHD), and often in 'healthy' individuals. Extreme physical activity may lead to marked elevations in creatine kinase MB and TnT levels. However, whether HsTnT elevations occur commonly after exercise stress testing (EST), and if so, whether this has clinical significance, needs clarification., Methods: To determine whether HsTnT levels become elevated after EST (Bruce protocol) to ≥95% of predicted maximum heart rate in presumed healthy subjects without overt CHD, we assayed HsTnT levels for ∼5h post-EST in 105 subjects (median age 37 years)., Results: Pre-EST HsTnT levels <5 ng/L were present in 31/32 (97%) of females and 52/74 (70%) of males. Post-EST, 13 (12%) subjects developed HsTnT levels >14 ng/L, with troponin elevation occurring at least three hours post-EST. Additionally, a detectable ≥ 50% increase in HsTnT levels (4.9→9ng/L) occurred in 28 (27%) of subjects who during EST achieved ≥ 95% of their predicted target heart rate. The median age of the subjects with HsTnT elevations to > 14ng/L post-EST was higher than those without such elevation (42 and 36 years respectively; p=0.038). At a median follow-up of 13 months no adverse events were recorded., Conclusion: The current study demonstrates that detectable elevations occur in HsTnT post-EST in 'healthy' subjects without overt CHD. Future studies should evaluate the clinical significance of detectable elevations in post-EST HsTnT with long-term follow-up for adverse cardiac events., (Copyright © 2016. Published by Elsevier B.V.)