Professor Gordon McKay has a long,exciting and distinguished professional career as a chemical engineer.From his early days in industry through to his most recent appointment as professor and Acting Head of Department...Professor Gordon McKay has a long,exciting and distinguished professional career as a chemical engineer.From his early days in industry through to his most recent appointment as professor and Acting Head of Department of Chemical and Biomolecular Engineering at the Hong Kong University of Science and Technology(HKUST),he has made a substantial contribution to the profession.展开更多
Initial success has been achieved in Hong Kong in controlling primary air pollutants,but ambient ozone levels kept increasing during the past three decades.Volatile organic compounds(VOCs)are important for mitigating ...Initial success has been achieved in Hong Kong in controlling primary air pollutants,but ambient ozone levels kept increasing during the past three decades.Volatile organic compounds(VOCs)are important for mitigating ozone pollution as its major precursors.This study analyzed VOC characteristics of roadside,suburban,and rural sites in Hong Kong to investigate their compositions,concentrations,and source contributions.Herewe showthat the TVOC concentrations were 23.05±13.24,12.68±15.36,and 5.16±5.48 ppbv for roadside,suburban,and rural sites between May 2015 to June 2019,respectively.By using Positive Matrix Factorization(PMF)model,six sources were identified at the roadside site over five years:Liquefied petroleum gas(LPG)usage(33%–46%),gasoline evaporation(8%–31%),aged air mass(11%–28%),gasoline exhaust(5%–16%),diesel exhaust(2%–16%)and fuel filling(75–9%).Similarly,six sources were distinguished at the suburban site,including LPG usage(30%–33%),solvent usage(20%–26%),diesel exhaust(14%–26%),gasoline evaporation(8%–16%),aged air mass(4%–11%),and biogenic emissions(2%–5%).At the rural site,four sources were identified,including aged airmass(33%–51%),solvent usage(25%–30%),vehicular emissions(11%–28%),and biogenic emissions(6%–12%).The analysis further revealed that fuel filling and LPG usage were the primary contributors to OFP and OH reactivity at the roadside site,while solvent usage and biogenic emissions accounted for almost half of OFP and OH reactivity at the suburban and rural sites,respectively.These findings highlight the importance of identifying and characterizing VOC sources at different sites to help policymakers develop targeted measures for pollution mitigation in specific areas.展开更多
Human skin exhibits a remarkable capability to perceive contact forces and environmental temperatures,providing complex information that is essential for its subtle control.Despite recent advancements in soft tactile ...Human skin exhibits a remarkable capability to perceive contact forces and environmental temperatures,providing complex information that is essential for its subtle control.Despite recent advancements in soft tactile sensors,accurately decoupling signals—specifically separating forces from directional orientation and temperature—remains a challenge thus resulting in failure to meet the advanced application requirements of robots.This study proposes,F3T,a multilayer soft sensor unit designed to achieve isolated measurements and mathematical decoupling of normal pressure,omnidirectional tangential forces,and temperature.We developed a circular coaxial magnetic film featuring a floating mount multilayer capacitor that facilitated the physical decoupling of normal and tangential forces in all directions.Additionally,we incorporated an ion gel-based temperature-sensing film into the tactile sensor.The proposed sensor was resilient to external pressures and deformations,and could measure temperature and significantly eliminate capacitor errors induced by environmental temperature changes.In conclusion,our novel design allowed for the decoupled measurement of multiple signals,laying the foundation for advancements in high-level robotic motion control,autonomous decision-making,and task planning.展开更多
Background:Adolescents face increasing academic and social pressures,which significantly impact their mental well-being and coping strategies.Physical activity(PA)has been recognized as crucial in promoting psychologi...Background:Adolescents face increasing academic and social pressures,which significantly impact their mental well-being and coping strategies.Physical activity(PA)has been recognized as crucial in promoting psychological resilience and social development.This study investigates the relationship between PA and adolescents’coping styles,with a particular focus on the mediating roles of friendship quality and psychological resilience.By examining these associations,the study aims to provide insights into how PA contributes to adolescents’ability to navigate challenges and develop adaptive coping mechanisms.Methods:This study employed a cross-sectional design and was conducted in Suzhou,Jiangsu Province,China.A total of 2288 high school students aged 15–18 were recruited using a convenience sampling approach.Data were collected through validated self-report questionnaires measuring PA,friendship quality,psychological resilience,and coping styles.Pearson correlation analysis and structural equation modelling(SEM)were applied to examine the relationships between variables and assess the mediating effects of friendship quality and psychological resilience in the association between PA and coping styles.Results:Significant positive correlations among variables:PA positively correlated with friendship quality(r=0.29,p<0.01),psychological resilience(r=0.26,p<0.01),and coping styles(r=0.26,p<0.01).Friendship quality and psychological resilience mediated the relationship between PA and coping styles,with direct effects accounting for 47.85%of the total effect.Indirect effects were distributed among three pathways:via friendship quality(15.38%),psychological resilience(27.56%),and a chain mediation of both(11.22%).Conclusion:The findings highlight the significant role of PA in enhancing adolescents’coping styles,with friendship quality and psychological resilience as key mediators.These results underscore the importance of promoting PA to strengthen social bonds,build resilience,and improve adaptive coping mechanisms among adolescents.Future research should explore additional mediating factors and employ longitudinal or experimental designs to establish causal relationships.展开更多
One-dimensional perovskites possess unique photoelectric properties that distinguish them from other perovskitetypes, making them a focal point in photoelectric research. In recent years, there has been a significant ...One-dimensional perovskites possess unique photoelectric properties that distinguish them from other perovskitetypes, making them a focal point in photoelectric research. In recent years, there has been a significant surge ininterest surrounding the synthesis and application of one-dimensional anisotropic perovskites, spurred by ad-vancementsin synthesis techniques and notable breakthroughs in novel methodologies and application proper-ties.This article provides a comprehensive review of the progress made in research on one-dimensionalanisotropic perovskites, detailing the synthesis mechanisms and potential pathways for performance enhance-mentin various applications. We highlight the crucial role of controllable synthesis and heterogeneous effect intailoring perovskite properties to boost application efficacy. Initially, this review examines the primary synthesismethods and mechanisms for creating heterogeneously induced one-dimensional anisotropic perovskites, cate-gorizingthem into two main approaches: the classical wet chemical synthesis, which utilizes selective ligands, andthe ligand-free, substrate-assisted method. The precision in controllable synthesis is essential for fabricatingheterogeneous structures, where the synthesized precursor, shape, and surface ligand significantly influence theinterfacial strength of the heterogenic interface. We also discuss the key features that must be improved for high-performanceapplications, exploring how heterogeneous effects can enhance performance and drive the devel-opmentof heterogeneous devices in various applications, such as photodetectors, solar cells, light-emitting di-odes,and photocatalysis. Conclusively, by highlighting the emerging potential and promising opportunitiesoffered by strategic heterogeneous construction, we forecast a dynamic and transformative future for their pro-ductionand application landscapes.展开更多
With the increasing construction of port facilities,cross-sea bridges,and offshore engineering projects,uplift piles embedded in marine sedimentary soft soil are becoming increasingly necessary.The load-displacement c...With the increasing construction of port facilities,cross-sea bridges,and offshore engineering projects,uplift piles embedded in marine sedimentary soft soil are becoming increasingly necessary.The load-displacement curve of uplift piles is crucial for evaluating their uplift bearing characteristics,which facilitates the risk evaluation,design,and construction of large infrastructural supports.In this study,a load-displacement curve model based on piezocone penetration test(CPTU)data is proposed via the load transfer method.Experimental tests are conducted to analyze the uplift bearing characteristics and establish a correlation between the proposed model and CPTU data.The results of the proposed load-displacement curve are compared with the results from numerical simulations and those calculated by previous methods.The results show that the proposed curves appropriately evaluated the uplift bearing characteristics and improved the accuracy in comparison with previous methods.展开更多
The hygroscopic properties of mixed aerosol particles are crucial for the application of remote sensing products of aerosol optical parameters in the study of air quality and climate at multiple scales. In this study,...The hygroscopic properties of mixed aerosol particles are crucial for the application of remote sensing products of aerosol optical parameters in the study of air quality and climate at multiple scales. In this study, the authors investigated aerosol optical properties as a func tion of relative humidity （RH） for two representative me tropolises： Beijing and Hong Kong. In addition to the RH data, mass concentrations of PM10 （particulate matter up to 10 utm in diameter） and aerosol scattering extinction coefficient （aext） data were used. The relationship between the mass scattering extinction efficiency （MEE, defined as O＇ext/PMl0） and RH can be expressed by regression func tions asf= 1.52x ＋ 0.29 （re= 0.77）,f= 1.42x ＋ 1.53 （re= 0.58）,f= 1.19x ＋ 0.65 （re= 0.59）, andf= 1.58x ＋ 1.30 （re = 0.61） for spring, summer, autumn, and winter, respec tively, in Beijing. Here, f represents MEE, x represents I/（1-RH）, and the coefficients of determination are pre sented in parentheses. Conversely, in Hong Kong, the corresponding functions are f= 1.98x- 1.40 （r^2= 0.55）,f = 1.32x - 0.36 （r^2 = 0.26）,f= 1.87x - 0.65 （r^2 = 0.64）, and f= 2.39x - 1.47 （r^2 = 0.72）, respectively. The MEE values for Hong Kong at high RHs （RH 〉 70%） are higher than those for Beijing, except in summer; this suggests that aerosols in Hong Kong are more hygroscopic than those in Beijing for the other three seasons, but the aerosol hy groscopicity is similarly high in summer over both cities. This study describes the effects of moisture on aerosol scattering extinction coefficients and provides a potential method of studying atmospheric visibility and ground level air quality using some of the optical remote sensing products of satellites.展开更多
The Hong Kong–Zhuhai–Macao Bridge(HZMB)involved the installation of 120 mega-cylinders with a diameter of 22 m,weights up to 513 t,and penetration depths up to 33 m using an eight-vibratory hammer group.Due to the l...The Hong Kong–Zhuhai–Macao Bridge(HZMB)involved the installation of 120 mega-cylinders with a diameter of 22 m,weights up to 513 t,and penetration depths up to 33 m using an eight-vibratory hammer group.Due to the lack of engineering experience on the drivability of large-diameter cylinders under multiple vibratory hammers,predicting the penetration rate and time of steel cylinders is an open challenge that has a considerable impact on the construction control of the HZMB.In this study,the vibratory penetration of large-diameter steel cylinders in the HZMB is investigated based on geological surveys,field monitoring,and drivability analysis.The vibratory penetration rate,installation accuracy,and dynamic responses of the steel cylinders at both the eastern and western artificial islands are analyzed.The dynamic soil resistance has a great influence on the cylinder drivability.However,the current design methods for estimating the vibratory driving soil resistance are proven inaccurate without considering the scale effects.Therefore,a modified method with a normalized effective area ratio A_(r,eff)is proposed in this study to calculate the vibratory soil resistance for open-ended thin-wall cylinders under unplugged conditions.Considering the scale effects on the vibratory driving soil resistance,the proposed method leads to closer results to the measured data,providing a reference for future engineering practice.展开更多
One new marine oligotrich ciliate, Omegastrombidium hongkongense n. sp., was isolated from a bloom of Noctiluca scuntillans near Port Shelter, Hong Kong. The morphology and infraciliature of this new species were stud...One new marine oligotrich ciliate, Omegastrombidium hongkongense n. sp., was isolated from a bloom of Noctiluca scuntillans near Port Shelter, Hong Kong. The morphology and infraciliature of this new species were studied on both living and protargol-stained specimens. Its phylogenetic position was discussed based on the sequence of the small subunit r RNA gene. O. hongkongense is different from its congeners with special characters. The cells are usually heart-shaped, and the cell size usually is(20–35) ×(20–30) μm in vivo. Its deep buccal cavity extends obliquely to about 1/2 of cell length. It shows prominent apical protrusion. The adoral zone of membranelles is divided into 17–19 collar membranelles and four buccal membranelles. It has one ball-like macronucleus. The girdle kinety forms a closed loop which obliquely surrounds the body. The ventral kinety and thigmotactic membranelles are not observed. The SSU r RNA sequence of O. hongkongense was close to those of Strombidium paracalkinsi and Varistrombidium kelum with approximately 99% similarity. In the phylogenetic trees, O. hongkongense can be grouped with O. elegans and V. kielum species with very low support(16% ML).展开更多
The special administrative regions of Hong Kong and Macao enjoy a high degree of autonomy from the national policy system in devising their local policies,including measures related to climate change.Hong Kong and Mac...The special administrative regions of Hong Kong and Macao enjoy a high degree of autonomy from the national policy system in devising their local policies,including measures related to climate change.Hong Kong and Macao each have their own climate change policies,some aspects of which are more advanced than policies in China's Mainland.While their high degree of policy autonomy has advantages,this has also isolated them from China's larger environmental management and practices that continue to advance at scale.This paper reviews the climate change policies of the two special administrative regions and analyzes their strengths and innovations,particularly in adaptation.It also identifies areas where there could be closer engagement,collaboration,and capacity-building with the China's Mainland,which has the potential for greater positive impacts,especially on a regional basis.展开更多
Study of Air Quality Objectives(AQOs)and long-term changes of air pollution plays a decisive role in formulating and refining pollution control strategies.In this study,10-year variations of six major air pollutants w...Study of Air Quality Objectives(AQOs)and long-term changes of air pollution plays a decisive role in formulating and refining pollution control strategies.In this study,10-year variations of six major air pollutants were analyzed at seven monitoring sites in Hong Kong region.The continuous decrease of annual averaged concentrations of NO_(2),SO_(2),CO,PM_(2.5)and PM_(10)and numbers of days with severe pollution conditions validated the efficiency of the series of air pollution control schemes implemented by the Hong Kong region government.However,there is still a big gap to meet the ultimate targets described by the World Health Organization.Besides,the concentration of O_(3)at roadside and urban stations increased by 135%±25%and 37%±18%from 2011 to 2020,respectively,meanwhile the highest 8 hr averaged O_(3)concentration was observed as 294μg/m^(3)at background station in 2020,which pointed out the increasing ozone pollution in Hong Kong region.There was a great decrease in the annual times of air quality health index(AQHI)laying in“high”,“very high”and“serious”categories from 2011 to 2020 with the decrease rate of 89.70%,91.30%and 89.74%at roadside stations,and 79.03%,95.98%and 72.73%at urban stations,respectively.Nevertheless,the number of days categorized as“high”or above at roadside station was twice more than that in the urban station during the past ten years.Thus,more policies and attentions should be given to the roadside air quality and its adverse health effect to pedestrians on street.展开更多
Analysis of the Direct Operating Cost(DOC) of aircraft is an important step towards achieving financially sustainable aviation operations. However, the value of the DOC for different aircraft types and flight scenario...Analysis of the Direct Operating Cost(DOC) of aircraft is an important step towards achieving financially sustainable aviation operations. However, the value of the DOC for different aircraft types and flight scenarios is not widely available. In this study, we perform a systematic analysis of the DOC of every wide-body passenger aircraft currently in production, using the method of the Association of European Airlines(AEA). The elements of the DOC, e.g. financial costs, maintenance costs, and flight costs, are evaluated individually. Several realistic flight scenarios are considered, each with differences in route distance, fuel price, passenger number, and seating arrangement. For each flight scenario, the most cost-efficient aircraft type is identified and evaluated in the context of operations from Hong Kong International Airport. The information provided in this study could be useful to airline operators and policy makers.展开更多
On 13 August 2010, a catastrophic debris flow with a volume of 1.17 million m3 occurred in Xiaojiagou Ravine near Yingxiu town of Wenchuan county in Sichuan Province, China. The main source material was the landslide ...On 13 August 2010, a catastrophic debris flow with a volume of 1.17 million m3 occurred in Xiaojiagou Ravine near Yingxiu town of Wenchuan county in Sichuan Province, China. The main source material was the landslide deposits retained in the ravine during the 2008 Wenchuan earthquake. This paper describes a two-dimensional hybrid numerical method that simulates the entire process of the debris flow from initiation to transportation and finally to deposition. The study area is discretized into a grid of square zones. A two dimensional finite difference method is then applied to simulate the rainfall-runoff and debris flow runout processes. The analysis is divided into three steps; namely, rainfall-runoff simulation, mixing water and solid materials, and debris flow runout simulation. The rainfall-runoff simulation is firstly conducted to obtain the cumulative runoff near the location of main source material and at the outlet of the first branch. The water and solid materials are then mixed to create an inflow hydrograph for the debris flow runout simulation. The occurrence time and volume of the debris flow can be estimated in this step. Finally the runout process of the debris flow is simulated. When the yield stress is high, it controls the deposition zone. When the yield stress is medium or low, both yield stress and viscosity influence the deposition zone. The flow velocity is largely influenced by the viscosity. The estimated yield stress by the equation, ty = pghsinO, and the estimated viscosity by the equation established by Bisantino et al. （2010） provide good estimates of the area of the debris flow fan and the distribution of deposition depth.展开更多
The effects of microstructure and its evolution on the macroscopic superelastic stress-strain response of polycrystalline Shape Memory Alloy(SMA)are studied by a microstructure-based constitutive model developed in th...The effects of microstructure and its evolution on the macroscopic superelastic stress-strain response of polycrystalline Shape Memory Alloy(SMA)are studied by a microstructure-based constitutive model developed in this paper.The model is established on the following basis:(1)the transformation conditions of the unconstrained single crystal SMA microdomain(to be distinguished from the bulk single crystal),which serve as the local criterion for the derivation of overall transfor- mation yield conditions of the polycrystal;(2)the micro-to macro-transition scheme by which the connection between the polycrystal aggregates and the single crystal microdomain is established and the macroscopic transformation conditions of the polycrystal SMA are derived;(3)the quantitative incorporation of three microstruc- ture factors(i.e.,nucleation,growth and orientation distribution of martensite)into the modeling.These microstructural factors are intrinsic of specific polycrystal SMA systems and the role of each factor in the macroscopic constitutive response is quan- titatively modeled.It is demonstrated that the interplay of these factors will result in different macroscopic transformation kinematics and kinetics which are responsible for the observed macroscopic stress-strain hardening or softening response,the latter will lead to the localization and propagation of transformation bands in TiNi SMA.展开更多
UV/chlorine process,as an emerging advanced oxidation process(AOP),was effective for removing micro-pollutants via various reactive radicals,but it also led to the changes of natural organic matter(NOM)and formation o...UV/chlorine process,as an emerging advanced oxidation process(AOP),was effective for removing micro-pollutants via various reactive radicals,but it also led to the changes of natural organic matter(NOM)and formation of disinfection byproducts(DBPs).By using negative ion electrospray ionization coupled with Fourier transform ion cyclotron resonance mass spectrometry(ESI FT-ICR MS),the transformation of Suwannee River NOM(SRNOM)and the formation of chlorinated DBPs(Cl-DBPs)in the UV/chlorine AOP and subsequent post-chlorination were tracked and compared with dark chlorination.In comparison to dark chlorination,the involvement of Cl O·,Cl·,and HO·in the UV/chlorine AOP promoted the transformation of NOM by removing the compounds owning higher aromaticity(AI mod)value and DBE(double-bond equivalence)/C ratio and causing the decrease in the proportion of aromatic compounds.Meanwhile,more compounds which contained only C,H,O,N atoms(CHON)were observed after the UV/chlorine AOP compared with dark chlorination via photolysis of organic chloramines or radical reactions.A total of 833 compounds contained C,H,O,Cl atoms(CHOCl)were observed after the UV/chlorine AOP,higher than 789 CHOCl compounds in dark chlorination,and one-chlorine-containing components were the dominant species.The different products from chlorine substitution reactions(SR)and addition reactions(AR)suggested that SR often occurred in the precursors owning higher H/C ratio and AR often occurred in the precursors owning higher aromaticity.Post-chlorination further caused the cleavages of NOM structures into small molecular weight compounds,removed CHON compounds and enhanced the formation of Cl-DBPs.The results provide information about NOM transformation and Cl-DBPs formation at molecular levels in the UV/chlorine AOP.展开更多
In this study,the effects of low temperature on aluminum(Ⅲ)(Al)hydrolysis were examined both theoretically and experimentally by constructing a solubility diagram for amorphous aluminum hydroxide(Al(OH)_3(am))and a d...In this study,the effects of low temperature on aluminum(Ⅲ)(Al)hydrolysis were examined both theoretically and experimentally by constructing a solubility diagram for amorphous aluminum hydroxide(Al(OH)_3(am))and a distribution diagram of hydrolyzed Al species.First,thermodynamic data of Al species at 4℃were calculated from that at 25℃.A well confirmed polymeric Al species, AlO_4Al_(12)(OH)_(24)^(7+)(Al_(13)),was involved in building the diagrams and,correspondingly,the non-linear simultaneous equations wit...展开更多
All-vanadium flow batteries(VFBs)are one of the most promising large-scale energy storage technologies.Conducting an operando quantitative analysis of the polarizations in VFBs under different conditions is essential ...All-vanadium flow batteries(VFBs)are one of the most promising large-scale energy storage technologies.Conducting an operando quantitative analysis of the polarizations in VFBs under different conditions is essential for developing high power density batteries.Here,we employ an operando decoupling method to quantitatively analyze the polarizations in each electrochemical and chemical reaction of VFBs under different catalytic conditions.Results show that the reduction reaction of V^(3+)presents the largest activation polarization,while the reduction reaction of VO_(2)^(+)primarily contributes to concentration polarizations due to the formation of the intermediate product V_(2)O_(3)^(3+).Additionally,it is found that the widely used electrode catalytic methods,incorporating oxygen functional groups and electrodepositing Bi,not only enhance the reaction kinetics but also exacerbate concentration polarizations simultaneously,especially during the discharge process.Specifically,in the battery with the high oxygen-containing electrodes,the negative side still accounts for the majority of activation loss(75.3%)at 200 mA cm^(-2),but it comes down to 36,9% after catalyzing the negative reactions with bismuth.This work provides an effective way to probe the limiting steps in flow batteries under various working conditions and offers insights for effectively enhancing battery performance for future developments.展开更多
A glacier hazard chain can form a long-runout mass flow and generate a large flood,affecting downstream areas hundreds of kilometers away from the initiating hazard site.This study focuses on the Yarlung Zangbo Daxiag...A glacier hazard chain can form a long-runout mass flow and generate a large flood,affecting downstream areas hundreds of kilometers away from the initiating hazard site.This study focuses on the Yarlung Zangbo Daxiagu.The objective is to address two key unresolved issues:the evolution of detached glacier materials into debris flows or debris floods and the amplification of the impact range and threats.A comprehensive framework is developed that considers the impacts of near-field and far-field hazards.Numerical modeling,remote sensing,and field investigations were integrated to understand the interactions,transformations,and amplifications of hazards in the glacier hazard chain.The results indicate that extensive,nearly saturated sediments on the glacier valley floor,when entrained,amplify the magnitude of the mass flow.The topography plays a crucial role.When the valley outlet is perpendicular to the river course,topographic obstacles cause immediate halting,resulting in the formation of high barrier dams.Conversely,when the glacier valley aligns nearly parallel to the river course,the mass flow can travel a much longer distance upon entering the river,causing an enlarged affected area.The barrier dams can breach rapidly,causing breaching floods that amplify the downstream impact from several kilometers to hundreds of kilometers.Our analysis reveals that the overall impacts remain spatially limited.Specifically,downstream areas along the Yarlung Zangbo-Brahmaputra River are unlikely to face greater threats from the upstream floods than local monsoon floods.Our findings provide the foundation for the management of glacier hazard chains.展开更多
In this study,bismuth oxyiodide with coexistence of plasmonic Bi and oxygen vacancy(Bi/BiO_(1-x)I)was successfully prepared and used towards photothermal and photocatalytic disinfection of pathogenic bacteria containi...In this study,bismuth oxyiodide with coexistence of plasmonic Bi and oxygen vacancy(Bi/BiO_(1-x)I)was successfully prepared and used towards photothermal and photocatalytic disinfection of pathogenic bacteria containing water.Plasmonic Bi and oxygen vacancies in Bi/BiO_(1-x)I induced a surface plasmon effect under the irradiation of simulated solar light from 500-900 nm and promoted the generation of hot electrons and reactive species(^(1)O^(2),h^(+)and·O_(2)^(-)).The catalyst showed promising performance for inactivation of E.coli K-12,with a 7.2 log inactivated achieved under the optimum conditions.A synergy between photothermal and photocatalytic inactivation was identified and discussed.The mechanisms of E.coli K-12 destruction were investigated.The destruction of extracellular antioxidant enzymes of E.coli K-12 was identified after inactivation.Moreover,the E.coli's membrane and its intracellular contents were attacked by the reactive species(^(1)O^(2),h^(+)and·O_(2)^(-))and the thermal effects.This work provides useful insights into the rational design of semimetal bismuth-mediated photocatalysts towards effective and sustainable water disinfection.展开更多
The Indonesian Throughflow(ITF)plays important roles in global ocean circulation and climate systems.Previous studies suggested the ITF interannual variability is driven by both the El Niño-Southern Oscillation(E...The Indonesian Throughflow(ITF)plays important roles in global ocean circulation and climate systems.Previous studies suggested the ITF interannual variability is driven by both the El Niño-Southern Oscillation(ENSO)and the Indian Ocean Dipole(IOD)events.The detailed processes of ENSO and/or IOD induced anomalies impacting on the ITF,however,are still not clear.In this study,this issue is investigated through causal relation,statistical,and dynamical analyses based on satellite observation.The results show that the driven mechanisms of ENSO on the ITF include two aspects.Firstly,the ENSO related wind field anomalies driven anomalous cyclonic ocean circulation in the western Pacific,and off equatorial upwelling Rossby waves propagating westward to arrive at the western boundary of the Pacific,both tend to induce negative sea surface height anomalies(SSHA)in the western Pacific,favoring ITF reduction since the develop of the El Niño through the following year.Secondly,the ENSO events modulate equatorial Indian Ocean zonal winds through Walker Circulation,which in turn trigger eastward propagating upwelling Kelvin waves and westward propagating downwelling Rossby waves.The Rossby waves are reflected into downwelling Kelvin waves,which then propagate eastward along the equator and the Sumatra-Java coast in the Indian Ocean.As a result,the wave dynamics tend to generate negative(positive)SSHA in the eastern Indian Ocean,and thus enhance(reduce)the ITF transport with time lag of 0-6 months(9-12 months),respectively.Under the IOD condition,the wave dynamics also tend to enhance the ITF in the positive IOD year,and reduce the ITF in the following year.展开更多
文摘Professor Gordon McKay has a long,exciting and distinguished professional career as a chemical engineer.From his early days in industry through to his most recent appointment as professor and Acting Head of Department of Chemical and Biomolecular Engineering at the Hong Kong University of Science and Technology(HKUST),he has made a substantial contribution to the profession.
基金supported by Hong Kong Environment Protection Department(Quotation Ref.18-06532)Hong Kong Innovation and Technology Fund(ITS/193/20FP)Hong Kong Research Grants Council(No.26304921).
文摘Initial success has been achieved in Hong Kong in controlling primary air pollutants,but ambient ozone levels kept increasing during the past three decades.Volatile organic compounds(VOCs)are important for mitigating ozone pollution as its major precursors.This study analyzed VOC characteristics of roadside,suburban,and rural sites in Hong Kong to investigate their compositions,concentrations,and source contributions.Herewe showthat the TVOC concentrations were 23.05±13.24,12.68±15.36,and 5.16±5.48 ppbv for roadside,suburban,and rural sites between May 2015 to June 2019,respectively.By using Positive Matrix Factorization(PMF)model,six sources were identified at the roadside site over five years:Liquefied petroleum gas(LPG)usage(33%–46%),gasoline evaporation(8%–31%),aged air mass(11%–28%),gasoline exhaust(5%–16%),diesel exhaust(2%–16%)and fuel filling(75–9%).Similarly,six sources were distinguished at the suburban site,including LPG usage(30%–33%),solvent usage(20%–26%),diesel exhaust(14%–26%),gasoline evaporation(8%–16%),aged air mass(4%–11%),and biogenic emissions(2%–5%).At the rural site,four sources were identified,including aged airmass(33%–51%),solvent usage(25%–30%),vehicular emissions(11%–28%),and biogenic emissions(6%–12%).The analysis further revealed that fuel filling and LPG usage were the primary contributors to OFP and OH reactivity at the roadside site,while solvent usage and biogenic emissions accounted for almost half of OFP and OH reactivity at the suburban and rural sites,respectively.These findings highlight the importance of identifying and characterizing VOC sources at different sites to help policymakers develop targeted measures for pollution mitigation in specific areas.
基金support by Hong Kong RGC General Research Fund(16217824,16213825,16203923,and 16217824)National Natural Science Foundation of China(N_HKUST638/23)+1 种基金Research Grants Council Joint Research Scheme(62361166630)Guangdong Basic and Applied Basic Research Foundation(2023B1515130007).
文摘Human skin exhibits a remarkable capability to perceive contact forces and environmental temperatures,providing complex information that is essential for its subtle control.Despite recent advancements in soft tactile sensors,accurately decoupling signals—specifically separating forces from directional orientation and temperature—remains a challenge thus resulting in failure to meet the advanced application requirements of robots.This study proposes,F3T,a multilayer soft sensor unit designed to achieve isolated measurements and mathematical decoupling of normal pressure,omnidirectional tangential forces,and temperature.We developed a circular coaxial magnetic film featuring a floating mount multilayer capacitor that facilitated the physical decoupling of normal and tangential forces in all directions.Additionally,we incorporated an ion gel-based temperature-sensing film into the tactile sensor.The proposed sensor was resilient to external pressures and deformations,and could measure temperature and significantly eliminate capacitor errors induced by environmental temperature changes.In conclusion,our novel design allowed for the decoupled measurement of multiple signals,laying the foundation for advancements in high-level robotic motion control,autonomous decision-making,and task planning.
基金supported by Jiangsu Province Education Science“14th Five-Year Plan”Project(No.C/2024/01/99).
文摘Background:Adolescents face increasing academic and social pressures,which significantly impact their mental well-being and coping strategies.Physical activity(PA)has been recognized as crucial in promoting psychological resilience and social development.This study investigates the relationship between PA and adolescents’coping styles,with a particular focus on the mediating roles of friendship quality and psychological resilience.By examining these associations,the study aims to provide insights into how PA contributes to adolescents’ability to navigate challenges and develop adaptive coping mechanisms.Methods:This study employed a cross-sectional design and was conducted in Suzhou,Jiangsu Province,China.A total of 2288 high school students aged 15–18 were recruited using a convenience sampling approach.Data were collected through validated self-report questionnaires measuring PA,friendship quality,psychological resilience,and coping styles.Pearson correlation analysis and structural equation modelling(SEM)were applied to examine the relationships between variables and assess the mediating effects of friendship quality and psychological resilience in the association between PA and coping styles.Results:Significant positive correlations among variables:PA positively correlated with friendship quality(r=0.29,p<0.01),psychological resilience(r=0.26,p<0.01),and coping styles(r=0.26,p<0.01).Friendship quality and psychological resilience mediated the relationship between PA and coping styles,with direct effects accounting for 47.85%of the total effect.Indirect effects were distributed among three pathways:via friendship quality(15.38%),psychological resilience(27.56%),and a chain mediation of both(11.22%).Conclusion:The findings highlight the significant role of PA in enhancing adolescents’coping styles,with friendship quality and psychological resilience as key mediators.These results underscore the importance of promoting PA to strengthen social bonds,build resilience,and improve adaptive coping mechanisms among adolescents.Future research should explore additional mediating factors and employ longitudinal or experimental designs to establish causal relationships.
基金supported by the National Natural Science Foundation of China(22272065)the Natural Science Foundation of Jiangsu Province(BK20211530)+1 种基金the Fundamental Research Funds for the Central Universities(JUSRP62218)the Key Research and Development Special Project of Yi'chun City,Jiangxi Province,China(2023ZDYFZX06).
文摘One-dimensional perovskites possess unique photoelectric properties that distinguish them from other perovskitetypes, making them a focal point in photoelectric research. In recent years, there has been a significant surge ininterest surrounding the synthesis and application of one-dimensional anisotropic perovskites, spurred by ad-vancementsin synthesis techniques and notable breakthroughs in novel methodologies and application proper-ties.This article provides a comprehensive review of the progress made in research on one-dimensionalanisotropic perovskites, detailing the synthesis mechanisms and potential pathways for performance enhance-mentin various applications. We highlight the crucial role of controllable synthesis and heterogeneous effect intailoring perovskite properties to boost application efficacy. Initially, this review examines the primary synthesismethods and mechanisms for creating heterogeneously induced one-dimensional anisotropic perovskites, cate-gorizingthem into two main approaches: the classical wet chemical synthesis, which utilizes selective ligands, andthe ligand-free, substrate-assisted method. The precision in controllable synthesis is essential for fabricatingheterogeneous structures, where the synthesized precursor, shape, and surface ligand significantly influence theinterfacial strength of the heterogenic interface. We also discuss the key features that must be improved for high-performanceapplications, exploring how heterogeneous effects can enhance performance and drive the devel-opmentof heterogeneous devices in various applications, such as photodetectors, solar cells, light-emitting di-odes,and photocatalysis. Conclusively, by highlighting the emerging potential and promising opportunitiesoffered by strategic heterogeneous construction, we forecast a dynamic and transformative future for their pro-ductionand application landscapes.
基金supported by the China Postdoctoral Science Foundation(Grant No.2024M760734)National Science Fund for Distinguished Young Scholars(Grant No.42225206)the National Natural Science Foundation of China(Grant Nos.41877231 and 42072299).
文摘With the increasing construction of port facilities,cross-sea bridges,and offshore engineering projects,uplift piles embedded in marine sedimentary soft soil are becoming increasingly necessary.The load-displacement curve of uplift piles is crucial for evaluating their uplift bearing characteristics,which facilitates the risk evaluation,design,and construction of large infrastructural supports.In this study,a load-displacement curve model based on piezocone penetration test(CPTU)data is proposed via the load transfer method.Experimental tests are conducted to analyze the uplift bearing characteristics and establish a correlation between the proposed model and CPTU data.The results of the proposed load-displacement curve are compared with the results from numerical simulations and those calculated by previous methods.The results show that the proposed curves appropriately evaluated the uplift bearing characteristics and improved the accuracy in comparison with previous methods.
基金supported by the"Strategic Priority Research Program" of the Chinese Academy of Sciences (Grant No. XDA05040000)the National Natural Science Foundation of China (Grant Nos. 40775002 and 41175020)the National High Technology Research and Development Program of China (863 Program, Grant No. SQ2010AA1221583001)
文摘The hygroscopic properties of mixed aerosol particles are crucial for the application of remote sensing products of aerosol optical parameters in the study of air quality and climate at multiple scales. In this study, the authors investigated aerosol optical properties as a func tion of relative humidity （RH） for two representative me tropolises： Beijing and Hong Kong. In addition to the RH data, mass concentrations of PM10 （particulate matter up to 10 utm in diameter） and aerosol scattering extinction coefficient （aext） data were used. The relationship between the mass scattering extinction efficiency （MEE, defined as O＇ext/PMl0） and RH can be expressed by regression func tions asf= 1.52x ＋ 0.29 （re= 0.77）,f= 1.42x ＋ 1.53 （re= 0.58）,f= 1.19x ＋ 0.65 （re= 0.59）, andf= 1.58x ＋ 1.30 （re = 0.61） for spring, summer, autumn, and winter, respec tively, in Beijing. Here, f represents MEE, x represents I/（1-RH）, and the coefficients of determination are pre sented in parentheses. Conversely, in Hong Kong, the corresponding functions are f= 1.98x- 1.40 （r^2= 0.55）,f = 1.32x - 0.36 （r^2 = 0.26）,f= 1.87x - 0.65 （r^2 = 0.64）, and f= 2.39x - 1.47 （r^2 = 0.72）, respectively. The MEE values for Hong Kong at high RHs （RH 〉 70%） are higher than those for Beijing, except in summer; this suggests that aerosols in Hong Kong are more hygroscopic than those in Beijing for the other three seasons, but the aerosol hy groscopicity is similarly high in summer over both cities. This study describes the effects of moisture on aerosol scattering extinction coefficients and provides a potential method of studying atmospheric visibility and ground level air quality using some of the optical remote sensing products of satellites.
基金supported by the National Natural Science Foundation of China(52001267)Tianjin Port Engineering Institute Co.,Ltd.,and Eunsung O&C Offshore Marine and Construction(EUNSUNG19EG01).
文摘The Hong Kong–Zhuhai–Macao Bridge(HZMB)involved the installation of 120 mega-cylinders with a diameter of 22 m,weights up to 513 t,and penetration depths up to 33 m using an eight-vibratory hammer group.Due to the lack of engineering experience on the drivability of large-diameter cylinders under multiple vibratory hammers,predicting the penetration rate and time of steel cylinders is an open challenge that has a considerable impact on the construction control of the HZMB.In this study,the vibratory penetration of large-diameter steel cylinders in the HZMB is investigated based on geological surveys,field monitoring,and drivability analysis.The vibratory penetration rate,installation accuracy,and dynamic responses of the steel cylinders at both the eastern and western artificial islands are analyzed.The dynamic soil resistance has a great influence on the cylinder drivability.However,the current design methods for estimating the vibratory driving soil resistance are proven inaccurate without considering the scale effects.Therefore,a modified method with a normalized effective area ratio A_(r,eff)is proposed in this study to calculate the vibratory soil resistance for open-ended thin-wall cylinders under unplugged conditions.Considering the scale effects on the vibratory driving soil resistance,the proposed method leads to closer results to the measured data,providing a reference for future engineering practice.
基金supported by the National Natural Science Foundation of China(No.31301868)the Hong Kong Research Grants Council(Nos.GRF 661610 and 661912)+2 种基金the Hong Kong Scholar Programme(No.HKSP13SC03)NSFC-Guangdong Province Joint Foundation(No.U1301 235)Natural Science Foundation of Guangdong Pro-vince(No.S2013040013192)
文摘One new marine oligotrich ciliate, Omegastrombidium hongkongense n. sp., was isolated from a bloom of Noctiluca scuntillans near Port Shelter, Hong Kong. The morphology and infraciliature of this new species were studied on both living and protargol-stained specimens. Its phylogenetic position was discussed based on the sequence of the small subunit r RNA gene. O. hongkongense is different from its congeners with special characters. The cells are usually heart-shaped, and the cell size usually is(20–35) ×(20–30) μm in vivo. Its deep buccal cavity extends obliquely to about 1/2 of cell length. It shows prominent apical protrusion. The adoral zone of membranelles is divided into 17–19 collar membranelles and four buccal membranelles. It has one ball-like macronucleus. The girdle kinety forms a closed loop which obliquely surrounds the body. The ventral kinety and thigmotactic membranelles are not observed. The SSU r RNA sequence of O. hongkongense was close to those of Strombidium paracalkinsi and Varistrombidium kelum with approximately 99% similarity. In the phylogenetic trees, O. hongkongense can be grouped with O. elegans and V. kielum species with very low support(16% ML).
文摘The special administrative regions of Hong Kong and Macao enjoy a high degree of autonomy from the national policy system in devising their local policies,including measures related to climate change.Hong Kong and Macao each have their own climate change policies,some aspects of which are more advanced than policies in China's Mainland.While their high degree of policy autonomy has advantages,this has also isolated them from China's larger environmental management and practices that continue to advance at scale.This paper reviews the climate change policies of the two special administrative regions and analyzes their strengths and innovations,particularly in adaptation.It also identifies areas where there could be closer engagement,collaboration,and capacity-building with the China's Mainland,which has the potential for greater positive impacts,especially on a regional basis.
基金supported by the Research Grants Council of Hong Kong Government(Project No.T24/504/17 and T31-603/21-N)he Environment and Conservation Fund of Hong Kong Governmentt(Project No.ECF 63/2019).
文摘Study of Air Quality Objectives(AQOs)and long-term changes of air pollution plays a decisive role in formulating and refining pollution control strategies.In this study,10-year variations of six major air pollutants were analyzed at seven monitoring sites in Hong Kong region.The continuous decrease of annual averaged concentrations of NO_(2),SO_(2),CO,PM_(2.5)and PM_(10)and numbers of days with severe pollution conditions validated the efficiency of the series of air pollution control schemes implemented by the Hong Kong region government.However,there is still a big gap to meet the ultimate targets described by the World Health Organization.Besides,the concentration of O_(3)at roadside and urban stations increased by 135%±25%and 37%±18%from 2011 to 2020,respectively,meanwhile the highest 8 hr averaged O_(3)concentration was observed as 294μg/m^(3)at background station in 2020,which pointed out the increasing ozone pollution in Hong Kong region.There was a great decrease in the annual times of air quality health index(AQHI)laying in“high”,“very high”and“serious”categories from 2011 to 2020 with the decrease rate of 89.70%,91.30%and 89.74%at roadside stations,and 79.03%,95.98%and 72.73%at urban stations,respectively.Nevertheless,the number of days categorized as“high”or above at roadside station was twice more than that in the urban station during the past ten years.Thus,more policies and attentions should be given to the roadside air quality and its adverse health effect to pedestrians on street.
文摘Analysis of the Direct Operating Cost(DOC) of aircraft is an important step towards achieving financially sustainable aviation operations. However, the value of the DOC for different aircraft types and flight scenarios is not widely available. In this study, we perform a systematic analysis of the DOC of every wide-body passenger aircraft currently in production, using the method of the Association of European Airlines(AEA). The elements of the DOC, e.g. financial costs, maintenance costs, and flight costs, are evaluated individually. Several realistic flight scenarios are considered, each with differences in route distance, fuel price, passenger number, and seating arrangement. For each flight scenario, the most cost-efficient aircraft type is identified and evaluated in the context of operations from Hong Kong International Airport. The information provided in this study could be useful to airline operators and policy makers.
基金support from Sichuan Provincial Department of Transportation and Communications,the National Basic Research Program of China (Grant No.2011CB013506)the Research Grants Council of the Hong Kong SAR (Grant No.622210)
文摘On 13 August 2010, a catastrophic debris flow with a volume of 1.17 million m3 occurred in Xiaojiagou Ravine near Yingxiu town of Wenchuan county in Sichuan Province, China. The main source material was the landslide deposits retained in the ravine during the 2008 Wenchuan earthquake. This paper describes a two-dimensional hybrid numerical method that simulates the entire process of the debris flow from initiation to transportation and finally to deposition. The study area is discretized into a grid of square zones. A two dimensional finite difference method is then applied to simulate the rainfall-runoff and debris flow runout processes. The analysis is divided into three steps; namely, rainfall-runoff simulation, mixing water and solid materials, and debris flow runout simulation. The rainfall-runoff simulation is firstly conducted to obtain the cumulative runoff near the location of main source material and at the outlet of the first branch. The water and solid materials are then mixed to create an inflow hydrograph for the debris flow runout simulation. The occurrence time and volume of the debris flow can be estimated in this step. Finally the runout process of the debris flow is simulated. When the yield stress is high, it controls the deposition zone. When the yield stress is medium or low, both yield stress and viscosity influence the deposition zone. The flow velocity is largely influenced by the viscosity. The estimated yield stress by the equation, ty = pghsinO, and the estimated viscosity by the equation established by Bisantino et al. （2010） provide good estimates of the area of the debris flow fan and the distribution of deposition depth.
基金The project supported by the Research Grant Committee(RGC)of Hong Kong SARthe National Natural Science Foundation of China and the Provincial Natural Foundation of Jiangxi Province of China
文摘The effects of microstructure and its evolution on the macroscopic superelastic stress-strain response of polycrystalline Shape Memory Alloy(SMA)are studied by a microstructure-based constitutive model developed in this paper.The model is established on the following basis:(1)the transformation conditions of the unconstrained single crystal SMA microdomain(to be distinguished from the bulk single crystal),which serve as the local criterion for the derivation of overall transfor- mation yield conditions of the polycrystal;(2)the micro-to macro-transition scheme by which the connection between the polycrystal aggregates and the single crystal microdomain is established and the macroscopic transformation conditions of the polycrystal SMA are derived;(3)the quantitative incorporation of three microstruc- ture factors(i.e.,nucleation,growth and orientation distribution of martensite)into the modeling.These microstructural factors are intrinsic of specific polycrystal SMA systems and the role of each factor in the macroscopic constitutive response is quan- titatively modeled.It is demonstrated that the interplay of these factors will result in different macroscopic transformation kinematics and kinetics which are responsible for the observed macroscopic stress-strain hardening or softening response,the latter will lead to the localization and propagation of transformation bands in TiNi SMA.
基金supported by the National Key Research and Development Program of China(No.2017YFE0133200)the National Natural Science Foundation of China(Nos.21876210 and 21806173)+1 种基金the Guangdong Provincial Science and Technology Planning Projects(No.2019A050503006)Hong Kong RGC(Nos.16206416 and T21-604/19-R)。
文摘UV/chlorine process,as an emerging advanced oxidation process(AOP),was effective for removing micro-pollutants via various reactive radicals,but it also led to the changes of natural organic matter(NOM)and formation of disinfection byproducts(DBPs).By using negative ion electrospray ionization coupled with Fourier transform ion cyclotron resonance mass spectrometry(ESI FT-ICR MS),the transformation of Suwannee River NOM(SRNOM)and the formation of chlorinated DBPs(Cl-DBPs)in the UV/chlorine AOP and subsequent post-chlorination were tracked and compared with dark chlorination.In comparison to dark chlorination,the involvement of Cl O·,Cl·,and HO·in the UV/chlorine AOP promoted the transformation of NOM by removing the compounds owning higher aromaticity(AI mod)value and DBE(double-bond equivalence)/C ratio and causing the decrease in the proportion of aromatic compounds.Meanwhile,more compounds which contained only C,H,O,N atoms(CHON)were observed after the UV/chlorine AOP compared with dark chlorination via photolysis of organic chloramines or radical reactions.A total of 833 compounds contained C,H,O,Cl atoms(CHOCl)were observed after the UV/chlorine AOP,higher than 789 CHOCl compounds in dark chlorination,and one-chlorine-containing components were the dominant species.The different products from chlorine substitution reactions(SR)and addition reactions(AR)suggested that SR often occurred in the precursors owning higher H/C ratio and AR often occurred in the precursors owning higher aromaticity.Post-chlorination further caused the cleavages of NOM structures into small molecular weight compounds,removed CHON compounds and enhanced the formation of Cl-DBPs.The results provide information about NOM transformation and Cl-DBPs formation at molecular levels in the UV/chlorine AOP.
文摘In this study,the effects of low temperature on aluminum(Ⅲ)(Al)hydrolysis were examined both theoretically and experimentally by constructing a solubility diagram for amorphous aluminum hydroxide(Al(OH)_3(am))and a distribution diagram of hydrolyzed Al species.First,thermodynamic data of Al species at 4℃were calculated from that at 25℃.A well confirmed polymeric Al species, AlO_4Al_(12)(OH)_(24)^(7+)(Al_(13)),was involved in building the diagrams and,correspondingly,the non-linear simultaneous equations wit...
基金supported by the Guangdong Major Project of Basic and Applied Basic Research(2023B0303000002)the National Natural Science Foundation of China(No.52206089)+3 种基金the Guangdong Basic and Applied Basic Research Foundation(2024A1515010288,2023B1515120005)the Natural Science Foundation of Shenzhen(JCYJ20230807093315033)the Shenzhen Engineering Research Center,Southern University of Science and Technology(No.XMHT20230208003)high level of special funds(G03034K001)。
文摘All-vanadium flow batteries(VFBs)are one of the most promising large-scale energy storage technologies.Conducting an operando quantitative analysis of the polarizations in VFBs under different conditions is essential for developing high power density batteries.Here,we employ an operando decoupling method to quantitatively analyze the polarizations in each electrochemical and chemical reaction of VFBs under different catalytic conditions.Results show that the reduction reaction of V^(3+)presents the largest activation polarization,while the reduction reaction of VO_(2)^(+)primarily contributes to concentration polarizations due to the formation of the intermediate product V_(2)O_(3)^(3+).Additionally,it is found that the widely used electrode catalytic methods,incorporating oxygen functional groups and electrodepositing Bi,not only enhance the reaction kinetics but also exacerbate concentration polarizations simultaneously,especially during the discharge process.Specifically,in the battery with the high oxygen-containing electrodes,the negative side still accounts for the majority of activation loss(75.3%)at 200 mA cm^(-2),but it comes down to 36,9% after catalyzing the negative reactions with bismuth.This work provides an effective way to probe the limiting steps in flow batteries under various working conditions and offers insights for effectively enhancing battery performance for future developments.
基金support from the National Natural Science Foundation of China(U20A20112,42061160480,42377196,and 52479095)the NSFC/RGC Joint Research Scheme(42061160480 and N_HKUST620/20)+1 种基金the Research Grants Council of the Hong Kong SAR Government(16203720,T22-606/23-R,and JRFS25266S09)the Project of Hetao Shenzhen-Hong Kong Science and Technology Innovation Cooperation Zone(HZQB-KCZYB-2020083)。
文摘A glacier hazard chain can form a long-runout mass flow and generate a large flood,affecting downstream areas hundreds of kilometers away from the initiating hazard site.This study focuses on the Yarlung Zangbo Daxiagu.The objective is to address two key unresolved issues:the evolution of detached glacier materials into debris flows or debris floods and the amplification of the impact range and threats.A comprehensive framework is developed that considers the impacts of near-field and far-field hazards.Numerical modeling,remote sensing,and field investigations were integrated to understand the interactions,transformations,and amplifications of hazards in the glacier hazard chain.The results indicate that extensive,nearly saturated sediments on the glacier valley floor,when entrained,amplify the magnitude of the mass flow.The topography plays a crucial role.When the valley outlet is perpendicular to the river course,topographic obstacles cause immediate halting,resulting in the formation of high barrier dams.Conversely,when the glacier valley aligns nearly parallel to the river course,the mass flow can travel a much longer distance upon entering the river,causing an enlarged affected area.The barrier dams can breach rapidly,causing breaching floods that amplify the downstream impact from several kilometers to hundreds of kilometers.Our analysis reveals that the overall impacts remain spatially limited.Specifically,downstream areas along the Yarlung Zangbo-Brahmaputra River are unlikely to face greater threats from the upstream floods than local monsoon floods.Our findings provide the foundation for the management of glacier hazard chains.
基金financially supported by the National Natural Science Foundation of China(Nos.21876212,21976214,41603097,21673086 and 52070195)the Science and Technology Research Programs of Guangdong Province(No.2019A1515011015)+2 种基金the Science and Technology Program of Guangzhou(No.201904010353)the Fundamental Research Funds for the Central Universities(No.19lgpy157)supported by the Start-up Funds for High-Level Talents of Sun Yat-sen University(No.3800018821111)。
文摘In this study,bismuth oxyiodide with coexistence of plasmonic Bi and oxygen vacancy(Bi/BiO_(1-x)I)was successfully prepared and used towards photothermal and photocatalytic disinfection of pathogenic bacteria containing water.Plasmonic Bi and oxygen vacancies in Bi/BiO_(1-x)I induced a surface plasmon effect under the irradiation of simulated solar light from 500-900 nm and promoted the generation of hot electrons and reactive species(^(1)O^(2),h^(+)and·O_(2)^(-)).The catalyst showed promising performance for inactivation of E.coli K-12,with a 7.2 log inactivated achieved under the optimum conditions.A synergy between photothermal and photocatalytic inactivation was identified and discussed.The mechanisms of E.coli K-12 destruction were investigated.The destruction of extracellular antioxidant enzymes of E.coli K-12 was identified after inactivation.Moreover,the E.coli's membrane and its intracellular contents were attacked by the reactive species(^(1)O^(2),h^(+)and·O_(2)^(-))and the thermal effects.This work provides useful insights into the rational design of semimetal bismuth-mediated photocatalysts towards effective and sustainable water disinfection.
基金The Fund of Laoshan Laboratory under contract No.LSKJ202202700the Basic Scientific Fund for National Public Research Institutes of China under contract No.2024Q02+1 种基金the National Natural Science Foundation of China under contract Nos 42076023 and 42430402the Global Change and Air-Sea InteractionⅡProject under contract No.GASI-01-ATP-STwin.
文摘The Indonesian Throughflow(ITF)plays important roles in global ocean circulation and climate systems.Previous studies suggested the ITF interannual variability is driven by both the El Niño-Southern Oscillation(ENSO)and the Indian Ocean Dipole(IOD)events.The detailed processes of ENSO and/or IOD induced anomalies impacting on the ITF,however,are still not clear.In this study,this issue is investigated through causal relation,statistical,and dynamical analyses based on satellite observation.The results show that the driven mechanisms of ENSO on the ITF include two aspects.Firstly,the ENSO related wind field anomalies driven anomalous cyclonic ocean circulation in the western Pacific,and off equatorial upwelling Rossby waves propagating westward to arrive at the western boundary of the Pacific,both tend to induce negative sea surface height anomalies(SSHA)in the western Pacific,favoring ITF reduction since the develop of the El Niño through the following year.Secondly,the ENSO events modulate equatorial Indian Ocean zonal winds through Walker Circulation,which in turn trigger eastward propagating upwelling Kelvin waves and westward propagating downwelling Rossby waves.The Rossby waves are reflected into downwelling Kelvin waves,which then propagate eastward along the equator and the Sumatra-Java coast in the Indian Ocean.As a result,the wave dynamics tend to generate negative(positive)SSHA in the eastern Indian Ocean,and thus enhance(reduce)the ITF transport with time lag of 0-6 months(9-12 months),respectively.Under the IOD condition,the wave dynamics also tend to enhance the ITF in the positive IOD year,and reduce the ITF in the following year.
