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Frontiers of Chemical Science and engineering 2022年第7期16卷 1149-1163页

作者： Xuesong Lu Xiaojiao Luo Warren A.Thompson Jeannie Z.Y.Tan MMercedes Maroto-Valer research centre for Carbon Solutions School of Engineering and Physical SciencesHeriot-Watt UniversityEdinburgh EH144ASUK

The production of solar fuels via the photoreduction of carbon dioxide to methane by titanium oxide is a promising process to control greenhouse gas emissions and provide alternative renewable fuels. Although several reaction mechanisms have been proposed, the detailed steps are still ambiguous, and the limiting factors are not well defined. To improve our understanding of the mechanisms of carbon dioxide photoreduction, a multiphysics model was developed using COMSOL. The novelty of this work is the computational fluid dynamic model combined with the novel carbon dioxide photoreduction intrinsic reaction kinetic model, which was built based on three-steps, namely gas adsorption, surface reactions and desorption, while the ultraviolet light intensity distribution was simulated by the Gaussian distribution model and Beer-Lambert model. The carbon dioxide photoreduction process conducted in a laboratory-scale reactor under different carbon dioxide and water moisture partial pressures was then modeled based on the intrinsic kinetic model. It was found that the simulation results for methane, carbon monoxide and hydrogen yield match the experiments in the concentration range of 10^(−4) mol·m^(–3) at the low carbon dioxide and water moisture partial pressure. Finally, the factors of adsorption site concentration, adsorption equilibrium constant, ultraviolet light intensity and temperature were evaluated.

关键词： carbon dioxide photoreduction computational fluid dynamic simulation kinetic model Langmuir adsorption

Toolpath Interpolation and Smoothing for Computer Numerical Control Machining of Freeform Surfaces: A Review

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International Journal of Automation and computing 2020年第1期17卷 1-16页

作者： Wen-Bin Zhong Xi-Chun Luo Wen-Long Chang Yu-Kui Cai Fei Ding Hai-Tao Liu Ya-Zhou Sun centre for Precision Manufacturing Department of DesignManufacture&Engineering Management(DMEM)University of StrathclydeGlasgow G11XJUK engineering and physical sciences research council(EPSRC)Future Metrology Hub Centre for Precision TechnologiesUniversity of HuddersfieldHuddersfield HD13DHUK School of Mechatronic engineering Harbin Institute of TechnologyHarbin 150001China

Driven by the ever increasing demand in function integration,more and more next generation high value-added products,such as head-up displays,solar concentrators and intra-ocular-lens,etc.,are designed to possess freeform(i.e.,non-rotational symmetric)*** toolpath,composed of high density of short linear and circular segments,is generally used in computer numerical control(CNC)systems to machine those ***,the discontinuity between toolpath segments leads to high-frequency fluctuation of feedrate and acceleration,which will decrease the machining efficiency and product surface *** by the ever-increasing need for high-speed high-precision machining of those products,many novel toolpath interpolation and smoothing approaches have been proposed in both academia and industry,aiming to alleviate the issues caused by the conventional toolpath representation and interpolation *** paper provides a comprehensive review of the state-of-the-art toolpath interpolation and smoothing approaches with systematic *** advantages and disadvantages of these approaches are *** future research directions are also offered.

关键词： Computer numerical control(CNC) toolpath interpolation smoothing freeform surface

The Severn Barrage and other tidal energy options:Hydrodynamic and power output modelling

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Science China(Technological sciences) 2009年第11期52卷 3413-3424页

作者： Roger A. Falconer Reza Ahmadian Hydro-environmental research centre School of Engineering Cardiff University Cardiff UK

Details are given herein of the current main proposals for tidal energy provision from the Severn Estuary, in the uk, with particular emphasis being focused on the Severn Barrage project, as originally promoted by the Severn Tidal Power Group. In particular, emphasis has focused on assessing the potential hydro-environmental impacts and power outputs of a barrage across the estuary, with an unstructured grid, high resolution, model being developed and applied to the estuary to assess the implications of each of five shortlisted proposed schemes on the hydrodynamic, geomorphologic, flood risk and faecal indicator organism changes within the estuary. An outline is given of recent research on power refinements to the model to assess the options for power generation. The results show that the Severn Barrage has the potential to reduce the tidal currents in a highly dynamic estuary. This leads to the reduction of suspended sediment loads (particularly upstream of the barrage), an increase of light penetration within the water column and, potentially, an increase in the benthic bio-diversity and the level of aquatic life in the estuary. The results also show that the Severn Barrage will reduce markedly the risk of flooding upstream of the barrage and to a lesser extent downstream of the structure. In contrast the alternative options have far less impact on flood risk changes. In addition to the Severn Barrage some results are shown herein for a typical lagoon option, namely the Fleming Lagoon.

关键词： marine renewable energy Severn Estuary hydrodynamic processes tidal power finite volume models

“Plasmonics”in free space:observation of giant wavevectors,vortices,and energy backflow in superoscillatory optical fields

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Light(Science & Applications) 2019年第1期8卷 1161-1169页

作者： Guanghui Yuan Edward T.F.Rogers Nikolay I.Zheludev centre for Disruptive Photonic Technologies The Photonic InstituteSchool of Physical and Mathematical SciencesNanyang Technological UniversitySingapore 637371Singapore Optoelectronics research centre and centre for Photonic Metamaterials University of SouthamptonHighfieldSouthampton SO171BJUK Institute for Life sciences University of SouthamptonHighfieldSouthampton SO171BJUK

Evanescent light can be localized at the nanoscale by resonant absorption in a plasmonic nanoparticle or taper or by transmission through a ***,a conventional lens cannot focus free-space light beyond half of the wavelength λ.Nevertheless,precisely tailored interference of multiple waves can form a hotspot in free space of an arbitrarily small size,which is known as ***,we report a new type of integrated metasurface interferometry that allows for the first time mapping of fields with a deep subwavelength resolution ~λ/*** findings reveal that an electromagnetic field near the superoscillatory hotspot has many features similar to those found near resonant plasmonic nanoparticles or nanoholes:the hotspots are surrounded by nanoscale phase singularities and zones where the phase of the superoscillatory field changes more than tenfold faster than a freepropagating plane *** with high local wavevectors are pinned to phase vortices and zones of energy backflow(~λ/20 in size)that contribute to tightening of the main focal spot size beyond the Abbe-Rayleigh *** observations reveal some analogy between plasmonic nanofocusing of evanescent waves and superoscillatory nanofocusing of free-space waves and prove the fundamental link between superoscillations and superfocusing,offering new opportunities for nanoscale metrology and imaging.

关键词： metrology free wave

Positive and negative effects of graphite flake and monolayer graphene oxide templates on protein crystallization

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Particuology 2023年第8期79卷 27-34页

作者： Zhichun Lin Wenqing Tian Yang Su Vikash Kumar Yadav Huaiyu Yang Department of Chemical engineering Loughborough UniversityLoughboroughLE113TUUK Institute of Materials research Tsinghua Shenzhen International Graduate SchoolTsinghua UniversityShenzhen518055China Human sciences research centre University of DerbyDE221GBUK

Heterogeneous template-induced nucleation is a promising way to regulate protein crystallization events and could be employed for purification processes and crystallographic *** crystallization process with graphite and graphene oxide,as heterogeneous templates,were *** than 640 hanging drops with different concentrations of Lysozyme(30,50,70,100 mg/mL)and NaCl(0.7,0.9,1.1,1.3,1.5 M)were crystallised at 4 ℃ with or without graphite/graphene oxide *** induction times and crystallization process were observed under the *** lysozyme in the solutions with graphite flakes nucleated faster under all the conditions than the lysozyme with equal experimental conditions without *** crystals preferred to grow around the edge of graphite flakes than on the flat *** the droplets with monolayer graphene oxide,more crystals appeared around gra-phene oxide particles,and the faster or slower nucleation processes with templates were dependent on the lysozyme and NaCl *** oxide templates strongly inhibited nucleation at high lysozyme concentrations but promoted nucleation at low lysozyme *** heterogeneous templates changed the crystal morphology and the crystallization *** crystals were observed in the solution with graphite templatesthan with graphene oxide templates and without any template.

关键词： Graphite Graphene oxide Protein crystallization Adsorption Heterogeneous nucleation Template technology

All-optical dynamic focusing of light via coherent absorption in a plasmonic metasurface

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Light(Science & Applications) 2017年第1期6卷 114-120页

作者： Maria Papaioannou Eric Plum Edward TF Rogers Nikolay I Zheludev Optoelectronics research centre and centre for Photonic Metamaterials University of SouthamptonHighfieldSouthampton SO171BJUK Institute for Life sciences University of SouthamptonHighfieldSouthampton SO171BJUK centre for Disruptive Photonic Technologies School of Physical and Mathematical Sciences and The Photonics InstituteNanyang Technological UniversitySingapore 637371Singapore

Vision,microscopy,imaging,optical data projection and storage all depend on focusing of *** focusing is conventionally achieved with mechanically reconfigurable lenses,spatial light modulators or *** we demonstrate that dynamic control of focusing can be achieved through coherent interaction of optical waves on a thin beam *** use a nanostructured plasmonic metasurface of subwavelength thickness as the beam splitter,allowing operation in the regimes of coherent absorption and coherent *** of light resulting from illumination of the plasmonic metasurface with a Fresnel zone pattern is controlled by another patterned beam projected on the same *** altering the control pattern,its phase,or its intensity,we switch the lens function on and off,and alter the focal spot’s depth,diameter and *** occurs as fast as the control beam is modulated and therefore tens of gigahertz modulation bandwidth is possible with electro-optical modulators,which is orders of magnitude faster than conventional dynamic focusing technologies.

关键词： all-optical dynamic focusing coherent control coherent perfect absorption metasurfaces

Achromatic super-oscillatory lenses with subwavelength focusing

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Light(Science & Applications) 2017年第1期6卷 615-622页

作者： Guang Hui Yuan Edward TF Rogers Nikolay I Zheludev centre for Disruptive Photonic Technologies The Photonic InstituteSchool of Physical and Mathematical SciencesNanyang Technological UniversitySingapore 637371Singapore Optoelectronics research centre and centre for Photonic Metamaterials University of SouthamptonHighfieldSouthampton SO171BJUK Institute for Life sciences University of SouthamptonHighfieldSouthampton SO171BJUK

Lenses are crucial to light-enabled *** lenses have been perfected to achieve near-diffraction-limited resolution and minimal chromatic ***,such lenses are bulky and cannot focus light into a hotspot smaller than a half-wavelength of *** filters,initially suggested by Toraldo di Francia,can overcome the resolution constraints of conventional lenses but are not intrinsically chromatically *** we report single-element planar lenses that not only deliver sub-wavelength focusing,thus beating the diffraction limit of conventional refractive lenses,but also focus light of different colors into the same *** the principle of super-oscillations,we designed and fabricated a range of binary dielectric and metallic lenses for visible and infrared parts of the spectrum that are manufactured on silicon wafers,silica substrates and optical fiber *** low-cost,compact lenses could be useful in mobile devices,data storage,surveillance,robotics,space applications,imaging,manufacturing with light and spatially resolved nonlinear microscopies.

关键词： achromatic super-oscillation super-resolution

Performance of a data-driven technique applied to changes in wave height and its effect on beach response

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Water Science and engineering 2016年第1期9卷 42-51页

作者： José M.Horrillo-Caraballo Harshinie Karunarathna Shun-qi Pan Dominic Reeve Energy&Environment research Group Zienkiewicz Centre for Computational EngineeringSwansea UniversityBay CampusSwansea SA1 8ENUK Hydro-environmental research centre School of EngineeringCardiff UniversityCardiff CF24 3AAUK

In this study the medium-term response of beach profiles was investigated at two sites： a gently sloping sandy beach and a steeper mixed sand and gravel beach. The former is the Duck site in North Carolina, on the east coast of the USA, which is exposed to Atlantic Ocean swells and storm waves, and the latter is the Milford-on-Sea site at Christchurch Bay, on the south coast of England, which is partially sheltered from Atlantic swells but has a directionally bimodal wave exposure. The data sets comprise detailed bathymetric surveys of beach profiles covering a period of more than 25 years for the Duck site and over 18 years for the Milford-on-Sea site. The structure of the data sets and the data-driven methods are described. Canonical correlation analysis （CCA） was used to find linkages between the wave characteristics and beach profiles. The sensitivity of the linkages was investigated by deploying a wave height threshold to filter out the smaller waves incrementally. The results of the analysis indicate that, for the gently sloping sandy beach, waves of all heights are important to the morphological response. For the mixed sand and gravel beach, filtering the smaller waves improves the statistical fit and it suggests that low-height waves do not play a primary role in the medium-term morohological resoonse, which is primarily driven by the intermittent larger storm waves.

关键词： Beach profile Canonical correlation analysis Data-driven technique Empirical orthogonal function Forecast Statistical model Wave height threshold

The friction of diamond-like carbon coatings in a water environment

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Friction 2013年第3期1卷 210-221页

作者： D.C.SUTTON G.LIMBERT D.STEWART R.J.K.WOOD National centre for Advanced Tribology at Southampton(nCATS) Engineering SciencesFaculty of Engineering and the EnvironmentUniversity of SouthamptonSouthamptonSO171BJUK Bioengineering Science research Group Engineering SciencesFaculty of Engineering and the EnvironmentUniversity of SouthamptonSouthamptonSO171BJUK Materials Chemistry and CorrosionRolls-RoyceDerbyDE217XXUK

Diamond-like carbon(DLC)coatings are known to provide beneficial mechanical and tribological properties in harsh *** combination of high wear resistance and low friction has led to their extensive use in any number of *** tribological performance of a DLC coating is varied however,and the frictional response is known to be strongly dependent on the surrounding environment,as well as the material composition and bonding structure of the DLC *** paper presents an up-to-date review on the friction of DLC coatings in a water environment,with a special focus on transfer layer formation and tribochemistry.

关键词： friction diamond-like carbon(DLC) water transfer layer tribochemistry review

Predicting pollutant removal in constructed wetlands using artificial neural networks(ANNs)

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Water Science and engineering 2020年第1期13卷 14-23页

作者： Christopher Kiiza Shun-qi Pan Bettina Bockelmann-Evans Akintunde Babatunde Hydro-environmental research centre School of EngineeringCardiff UniversityThe ParadeCardiff CF243AAUK School of Civil engineering University of LeedsLeeds LS29JTUK

Growth in urban population,urbanisation,and economic development has increased the demand for water,especially in water-scarce ***,sustainable approaches to water management are needed to cope with the effects of the urbanisation on the water *** study aimed to design novel configurations of tidal-flow vertical subsurface flow constructed wetlands(VFCWs)for treating urban stormwater.A series of laboratory experiments were conducted with semi-synthetic influent stormwater to examine the effects of the design and operation variables on the performance of the VFCWs and to identify optimal design and operational strategies,as well as maintenance *** results show that the VFCWs can significantly reduce pollutants in urban stormwater,and that pollutant removal was related to specific VFCW *** based on the artificial neural network(ANN)method were built using inputs derived from data exploratory techniques,such as analysis of variance(ANOVA)and principal component analysis(PCA).It was found that PCA reduced the dimensionality of input variables obtained from different experimental design *** results show a satisfactory generalisation for predicting nitrogen and phosphorus removal with fewer variable inputs,indicating that monitoring costs and time can be reduced.

关键词： Constructed wetlands Urban stormwater Pollutant removal Artificial neural networks(ANNs) Principal component analysis(PCA)