Nickel-rich cathode materials have attracted considerable interest because of their high specific capacities,voltage ranges,and low cost.However,serious capacity attenuation and poor rate performance limit their appli...Nickel-rich cathode materials have attracted considerable interest because of their high specific capacities,voltage ranges,and low cost.However,serious capacity attenuation and poor rate performance limit their application.This study proposes a novel strategy to improve the cycle stability of the nickel-rich LiNi0.sCo0.1Mn0.1O2(NCM811)layer material by designing core-shell LiNio.sCoo.1 Mno.102(CS-NCM811).CS-NCM811 is designed by the characteristic reaction between dimethylglyoxime(C4H8N2O2)and nickel ion to form Ni(C4H7N2O2)2-The CS-NCM811 is characterized with high nickel content in its core and high manganese content on its surface,leading to a high capacity and excellent cycle stability.The capacity retention of CS-NCM811 was 72.8%,much higher than that of NCM811(47.1%)after 500 cycles at a rate of 5 C.Not only is this method a no vel strategy to desig n high capacity cathode materials but also provides some new in sights into the cycle stability of nickel-rich layered cathode materials.展开更多
Nonequilibrium molecular dynamics(NEMD) simulations have provided unique insights into the nanoscale behaviour of lubricants under shear. This review discusses the early history of NEMD and its progression from a tool...Nonequilibrium molecular dynamics(NEMD) simulations have provided unique insights into the nanoscale behaviour of lubricants under shear. This review discusses the early history of NEMD and its progression from a tool to corroborate theories of the liquid state, to an instrument that can directly evaluate important fluid properties, towards a potential design tool in tribology. The key methodological advances which have allowed this evolution are also highlighted. This is followed by a summary of bulk and confined NEMD simulations of liquid lubricants and lubricant additives, as they have progressed from simple atomic fluids to ever more complex, realistic molecules. The future outlook of NEMD in tribology, including the inclusion of chemical reactivity for additives, and coupling to continuum methods for large systems, is also briefly discussed.展开更多
Low-electrode capacitive deionization(FCDI)is an emerging desalination technology with great potential for removal and/or recycling ions from a range of waters.However,it still suffers from inefficient charge transfer...Low-electrode capacitive deionization(FCDI)is an emerging desalination technology with great potential for removal and/or recycling ions from a range of waters.However,it still suffers from inefficient charge transfer and ion transport kinetics due to weak turbulence and low electric intensity in flow electrodes,both restricted by the current collectors.Herein,a new tip-array current collector(designated as T-CC)was developed to replace the conventional planar current collectors,which intensifies both the charge transfer and ion transport significantly.The effects of tip arrays on flow and electric fields were studied by both computational simulations and electrochemical impedance spectroscopy,which revealed the reduction of ion transport barrier,charge transport barrier and internal resistance.With the voltage increased from 1.0 to 1.5 and 2.0 V,the T-CC-based FCDI system(T-FCDI)exhibited average salt removal rates(ASRR)of 0.18,0.50,and 0.89μmol cm^(-2) min^(-1),respectively,which are 1.82,2.65,and 2.48 folds higher than that of the conventional serpentine current collectors,and 1.48,1.67,and 1.49 folds higher than that of the planar current collectors.Meanwhile,with the solid content in flow electrodes increased from 1 to 5 wt%,the ASRR for T-FCDI increased from 0.29 to 0.50μmol cm^(-2) min^(-1),which are 1.70 and 1.67 folds higher than that of the planar current collectors.Additionally,a salt removal efficiency of 99.89%was achieved with T-FCDI and the charge efficiency remained above 95%after 24 h of operation,thus showing its superior long-term stability.展开更多
Mixed ionic electronic conductors(MIECs)have attracted increasing attention as anode materials for solid oxide fuel cells(SOFCs)and they hold great promise for lowering the operation temperature of SOFCs.However,there...Mixed ionic electronic conductors(MIECs)have attracted increasing attention as anode materials for solid oxide fuel cells(SOFCs)and they hold great promise for lowering the operation temperature of SOFCs.However,there has been a lack of understanding of the performance-limiting factors and guidelines for rational design of composite metal-MIEC electrodes.Using a newly-developed approach based on 3 D-tomography and electrochemical impedance spectroscopy,here for the first time we quantify the contribution of the dual-phase boundary(DPB)relative to the three-phase boundary(TPB)reaction pathway on real MIEC electrodes.A new design strategy is developed for Ni/gadolinium doped ceria(CGO)electrodes(a typical MIEC electrode)based on the quantitative analyses and a novel Ni/CGO fiber-matrix structure is proposed and fabricated by combining electrospinning and tape-casting methods using commercial powders.With only 11.5 vol%nickel,the designer Ni/CGO fiber-matrix electrode shows 32%and 67%lower polarization resistance than a nano-Ni impregnated CGO scaffold electrode and conventional cermet electrode respectively.The results in this paper demonstrate quantitatively using real electrode structures that enhancing DPB and hydrogen kinetics are more efficient strategies to enhance electrode performance than simply increasing TPB.展开更多
As both a beneficiary of global supply chain integration and a contributor to the creation of a new supply chain ecosystem,China is of immense importance to the growth of international supply chains.For example,it’s ...As both a beneficiary of global supply chain integration and a contributor to the creation of a new supply chain ecosystem,China is of immense importance to the growth of international supply chains.For example,it’s manufacturing industry is indispensable across every stage of the global supply chain from raw material to intermediate goods production and the assembly of finished products.And with a large consumer base,China has been the place where global goods and services are consumed.展开更多
It is increasingly important to monitor sliding interfaces within machines,since this is where both energy is lost,and failures occur.Acoustic emission(AE)techniques offer a way to monitor contacts remotely without re...It is increasingly important to monitor sliding interfaces within machines,since this is where both energy is lost,and failures occur.Acoustic emission(AE)techniques offer a way to monitor contacts remotely without requiring transparent or electrically conductive materials.However,acoustic data from sliding contacts is notoriously complex and difficult to interpret.Herein,we simultaneously measure coefficient of friction(with a conventional force transducer)and acoustic emission(with a piezoelectric sensor and high acquisition rate digitizer)produced by a steel‒steel rubbing contact.Acquired data is then used to train machine learning(ML)algorithms(e.g.,Gaussian process regression(GPR)and support vector machine(SVM))to correlated acoustic emission with friction.ML training requires the dense AE data to first be reduced in size and a range of processing techniques are assessed for this(e.g.,down-sampling,averaging,fast Fourier transforms(FFTs),histograms).Next,fresh,unseen AE data is given to the trained model and the resulting friction predictions are compared with the directly measured friction.There is excellent agreement between the measured and predicted friction when the GPR model is used on AE histogram data,with root mean square(RMS)errors as low as 0.03 and Pearson correlation coefficients reaching 0.8.Moreover,predictions remain accurate despite changes in test conditions such as normal load,reciprocating frequency,and stroke length.This paves the way for remote,acoustic measurements of friction in inaccessible locations within machinery to increase mechanical efficiency and avoid costly failure/needless maintenance.展开更多
Artificial muscles are capable of generating actuation in microsystems with outstanding compliance.Recent years have witnessed a growing academic interest in artificial muscles and their application in many areas,such...Artificial muscles are capable of generating actuation in microsystems with outstanding compliance.Recent years have witnessed a growing academic interest in artificial muscles and their application in many areas,such as soft robotics and biomedical devices.This paper aims to provide a comparative review of recent advances in artificial muscle based on various operating mechanisms.The advantages and limitations of each operating mechanism are analyzed and compared.According to the unique application requirements and electrical and mechanical properties of the muscle types,we suggest suitable artificial muscle mechanisms for specific microsystem applications.Finally,we discuss potential strategies for energy delivery,conversion,and storage to promote the energy autonomy of microrobotic systems at a system level.展开更多
Emerging evidence suggests that plasma membrane calcium ATPases (PMCAs) play a key role as regulators of calcium-triggered signal transduction pathways via interaction with partner proteins. PMCAs regulate these pathw...Emerging evidence suggests that plasma membrane calcium ATPases (PMCAs) play a key role as regulators of calcium-triggered signal transduction pathways via interaction with partner proteins. PMCAs regulate these pathways by targeting specific proteins to cellular sub-domains where the levels of intracellular freecalcium are kept low by the calcium ejection properties of PMCAs. According to this model, PMCAs have been shown to interact functionally with the calcium-sensitive proteins neuronal nitric oxide synthase, calmodulindependent serine protein kinase, calcineurin and endothelial nitric oxidase synthase. Transgenic animals with altered expression of PMCAs are being used to evaluate the physiological significance of these interactions. To date, PMCA interactions with calcium-dependent partner proteins have been demonstrated to play a crucial role in the pathophysiology of the cardiovascular system via regulation of the nitric oxide and calcineurin/nuclear factor of activated T cells pathways. This new evidence suggests that PMCAs play a more sophisticated role than the mere ejection of calcium from the cells, by acting as modulators of signaling transduction pathways.展开更多
Point defects are a universal feature of crystals.Their identification is addressed by combining experimental measurements with theoretical models.The standard modelling approach is,however,prone to missing the ground...Point defects are a universal feature of crystals.Their identification is addressed by combining experimental measurements with theoretical models.The standard modelling approach is,however,prone to missing the ground state atomic configurations associated with energy-lowering reconstructions from the idealised crystallographic environment.Missed ground states compromise the accuracy of calculated properties.To address this issue,we report an approach to navigate the defect configurational landscape using targeted bond distortions and rattling.Application of our workflow to eight materials(CdTe,GaAs,Sb_(2)S_(3),Sb_(2)Se_(3),CeO_(2),In_(2)O_(3),ZnO,anatase-TiO_(2))reveals symmetry breaking in each host crystal that is not found via conventional local minimisation techniques.The point defect distortions are classified by the associated physico-chemical factors.We demonstrate the impact of these defect distortions on derived properties,including formation energies,concentrations and charge transition levels.Our work presents a step forward for quantitative modelling of imperfect solids.展开更多
Large-area manufacturing of flexible nanoscale electronics has long been sought by the printed electronics industry.However,the lack of a robust,reliable,high throughput and low-cost technique that is capable of deliv...Large-area manufacturing of flexible nanoscale electronics has long been sought by the printed electronics industry.However,the lack of a robust,reliable,high throughput and low-cost technique that is capable of delivering high-performance functional devices has hitherto hindered commercial exploitation.Herein we report on the extensive range of capabilities presented by adhesion lithography(a-Lith),an innovative patterning technique for the fabrication of coplanar nanogap electrodes with arbitrarily large aspect ratio.We use this technique to fabricate a plethora of nanoscale electronic devices based on symmetric and asymmetric coplanar electrodes separated by a nanogap<15 nm.We show that functional devices including self-aligned-gate transistors,radio frequency diodes and rectifying circuits,multi-colour organic light-emitting nanodiodes and multilevel non-volatile memory devices,can be fabricated in a facile manner with minimum process complexity on a range of substrates.The compatibility of the formed nanogap electrodes with a wide range of solution processable semiconductors and substrate materials renders a-Lith highly attractive for the manufacturing of large-area nanoscale opto/electronics on arbitrary size and shape substrates.展开更多
Ball burnishing routine permits through a simple,fast and economical manner to obtain free chip on the manufactured parts.It generates a superior surface finish by rotating a ball tool against a workpiece.The burnishi...Ball burnishing routine permits through a simple,fast and economical manner to obtain free chip on the manufactured parts.It generates a superior surface finish by rotating a ball tool against a workpiece.The burnishing process is commonly developed in industry in order to improve the surface quality,which is a critical issue in the manufacturing sector.An experimental study were carried out to determine the best surface quality for magnesium alloy subjected to d iff ere ni medium.Burnishing of magnesium alloy was performed varying four different mediums and combining different burnishing parameters.To design the experiment were used the classical Taguchi method through which were developed the L16 orthogonal array.This strategy allowed to detect the driving parameters that generate the best surface roughness value by computing the signal-to-noise ratio.The driving parameters values for this study are 400 N(force),0.05 mm/min(feed rate),three number of passes and boron oil as medium.The results are paramount important for designing heavy parts used in transportation vehicles such as automobiles,airplanes,high-speed trains etc.展开更多
Surface-enhanced Raman scattering(SERS)substrates play important roles for the enhancement of inelastic scattering signals.Traditional substrates such as roughened electrodes and colloidal aggregates suffer from well-...Surface-enhanced Raman scattering(SERS)substrates play important roles for the enhancement of inelastic scattering signals.Traditional substrates such as roughened electrodes and colloidal aggregates suffer from well-known signal reproducibility issues,whereas for current dominant two-dimensional planar systems,the hot spot distributions are limited by the zero-,one-or two-dimensional plane.The introduction of a three-dimensional(3D)system such as a pyramid geometry breaks the limitation of a single Cartesian SERS-active area and extends it into the z-direction,with the tip potentially offering additional benefits of strong field enhancement and high sensitivity.However,current 3D pyramidal designs are restricted to film deposition on prepared pyramid templates or self-assembly in pyramidal molds with spherical building blocks,hence limiting their SERS effectiveness.Here,we report on the fabrication of a new class of low cost and well-defined plasmonic nanoparticle pyramid arrays from different anisotropic shaped nanoparticles using combined top-down lithography and bottom-up self-assembly approach.These pyramids exhibit novel optical scattering properties that can be exploited for the design of reproducible and sensitive SERS substrate.The SERS intensity was found to decrease drastically in accordance with a power law function as the focal planes move from the apex of the pyramid structure towards the base.In comparison to sphere-based building blocks,pyramids assembled from anisotropic rhombic dodecahedral gold nanocrystals with numerous sharp tips exhibited the strongest SERS performance.Graphical Abstract Macroscale pyramidal array films with plasmonic tunability as a new class of SERS substrate for sensitive detection of chemicals.展开更多
Color language has important meaning for children’s picture books.Understanding children’s preferences in terms of color language will be helpful when designers model computerized picture books in order to adapt to ...Color language has important meaning for children’s picture books.Understanding children’s preferences in terms of color language will be helpful when designers model computerized picture books in order to adapt to children’s visual senses and effectively stimulate children’s interest in reading.In this study,we aimed to further explore the general characteristics of children’s preference for colors,color depth and color matching forms in picture books.For the study,256 children between the ages of three and six were selected and divided into four groups.According to the implementation needs of the children’s color preference test,these childrenwere asked to complete a series of tasks so that their choices in the tasks could subsequently be analyzed.The tasks included making the following choices:selecting their preferred colors from nine options(red,orange,yellow,green,cyan,blue,purple,black and white);selecting their preferred color brightness fromthree different color shades;and indicating their preferences in relation to complementary colors,matching colors and pure colors.The experimental results showed that children aged between three and six mainly favor red,blue and yellow,and colors with a high degree of brightness.As children grow older,boys tend to prefer blue,and girls tend to prefer pink,with red remaining the favorite color of both genders.As for complementary colors,matching colors and solid colors,three-to six-year-old children prefer solid colors.In conclusion,it seems that color language preferences in children between the ages of three and six are very similar,which could be of use when designing children’s picture books to match their visual vocabulary and psychological cognition.展开更多
Titanium dioxide was deposited from aqueous suspension onto cellulosic surfaces. Titania was sourced from Degussa （P25TM, 70：30 anatase：rutile）. Dry uptake of particles was shown to be rapid and dominant with one-...Titanium dioxide was deposited from aqueous suspension onto cellulosic surfaces. Titania was sourced from Degussa （P25TM, 70：30 anatase：rutile）. Dry uptake of particles was shown to be rapid and dominant with one-third of the deposition occurring in less than 30 s and over one-half in the first minute. Isotherms were recorded to compare the rate of titanium deposition on dry and pre-wetted cotton. In the dry case uptake reached a maximum in 30 min whereas in the pre-wetted case the uptake was seen to continue beyond 180 min. A broad trend of higher deposition occurring at lower pH was seen, corresponding to the region where surface charges were opposite and thus attractive. Dry pickup was less significant at high pH. The response to varying ionic strength was complex and was attributed to the combined effect of charge screening, particle aggregation and consequent particle entrapment or occlusion. Titania deposition into the interstices of woven cotton sheets resulted in the formation of inorganic, nanoparticulate skeletons which could be isolated by controlled combustion of the cellulose and thus cotton was suggested to have potential for the templated synthesis of high surface area semiconductor materials.展开更多
Background:Poverty increases the risk of contracting infectious diseases and therefore exposure to antibiotics.Yet there is lacking evidence on the relationship between income and non-income dimensions of poverty and ...Background:Poverty increases the risk of contracting infectious diseases and therefore exposure to antibiotics.Yet there is lacking evidence on the relationship between income and non-income dimensions of poverty and antimicrobial resistance.Investigating such relationship would strengthen antimicrobial stewardship interventions.Methods:A systematic review was conducted following Preferred Reporting Items for Systematic Reviews and Meta-Analyses(PRISMA)guidelines.PubMed,Ovid,MEDLINE,EMBASE,Scopus,CINAHL,PsychINFO,EBSCO,HMIC,and Web of Science databases were searched in October 2016.Prospective and retrospective studies reporting on income or non-income dimensions of poverty and their influence on colonisation or infection with antimicrobial-resistant organisms were retrieved.Study quality was assessed with the Integrated quality criteria for review of multiple study designs(ICROMS)tool.Results:Nineteen articles were reviewed.Crowding and homelessness were associated with antimicrobial resistance in community and hospital patients.In high-income countries,low income was associated with Streptococcus pneumoniae and Acinetobacter baumannii resistance and a seven-fold higher infection rate.In low-income countries the findings on this relation were contradictory.Lack of education was linked to resistant S.pneumoniae and Escherichia coli.Two papers explored the relation between water and sanitation and antimicrobial resistance in low-income settings.Conclusions:Despite methodological limitations,the results suggest that addressing social determinants of poverty worldwide remains a crucial yet neglected step towards preventing antimicrobial resistance.展开更多
The stable isotope systems of the transition metals potentially provide constraints on the current and past operation of the biological pump,and on the state of ocean redox in Earth history.Here we focus on two exempl...The stable isotope systems of the transition metals potentially provide constraints on the current and past operation of the biological pump,and on the state of ocean redox in Earth history.Here we focus on two exemplar metals,nickel(Ni)and zinc(Zn).The oceanic dissolved pool of both elements is isotopically heavier than the known inputs,implying an output with light isotope compositions.The modern oceanic cycle of both these elements is dominated by biological uptake into photosynthesised organic matter and output to sediment.It is increasingly clear,however,that such uptake is associated with only very minor isotope fractionation.We suggest that the isotopic balance is instead closed by the sequestration of light isotopes to sulphide in anoxic and organic-rich sediments,so that it is ocean chemistry that controls these isotope systems,and suggesting a different but equally interesting array of questions in Earth history that can be addressed with these systems.展开更多
The book Yi Xue Shi(《医学史》History of Medicine)was written and edited by Cecilia Mettler and Fred Mettler couple,published in 1947.The book is about the literature research of systematic introduction to the history...The book Yi Xue Shi(《医学史》History of Medicine)was written and edited by Cecilia Mettler and Fred Mettler couple,published in 1947.The book is about the literature research of systematic introduction to the history of medical development worldwide.The book provides a detailed description of the development of various medical disciplines and subjects through various documents and the authors and publication dates.Especially,Prof.Mettler has introduced the Chinese Yin and Yang(阴阳)and the five element theory(五行学说)and Shen Nung’s Materia Medica(神农本草)in this book.展开更多
There is keen interest in using Ti alloys as lightweight structural materials for aerospace and automotive industries.However,a long-standing problem for these materials is their poor oxidation resistance.Herein,we de...There is keen interest in using Ti alloys as lightweight structural materials for aerospace and automotive industries.However,a long-standing problem for these materials is their poor oxidation resistance.Herein,we designed and fabricated a Ti_(5)Si_(3) reinforced Ti-4(wt.%)Mo composite with two-scale network architecture by low energy milling and spark plasma sintering.It displays superior oxidation resistance at 800°C owing to the in-situ formation of a multi-component surface layer.This oxide layer has a dense grain size gradient structure that consists of an outer TiO_(2)layer and an inner SiO_(2)-padding-TiO_(2) layer,which has remarkable oxidation resistance and thermal stability.Furthermore,it was revealed that the hitherto unknown interaction between Ti_(5)Si_(3) reinforcement and nitrogen during oxidation would contribute to the formation of a TiN nano-twin interface layer,which accommodates the thermal mismatch strain between the oxide layer and matrix.This,along with high adhesion,confers excellent thermal cycling life with no cracking or spallation during long-term oxidation.In this regard,the secure operating temperature of this new composite can be increased to 800°C,which provides a design pathway for a new family of Ti matrix composites for high-temperature applications.展开更多
In this manuscript, we present an explicit way to describe the violation of CP symmetry in the standard model (SM) of electrweak interactions. In such a way, complex Cabbibo-Kobayashi-Maskawa (CKM) matrices are achiev...In this manuscript, we present an explicit way to describe the violation of CP symmetry in the standard model (SM) of electrweak interactions. In such a way, complex Cabbibo-Kobayashi-Maskawa (CKM) matrices are achieved which stand for the violation of CP symmetry. At the beginning, two necessary but not sufficient conditions for yielding a complex CKM matrix are stated as criteria. Then we found an interesting condition between the real and imaginary parts of a Hermitian 3 × 3 matrix which may provide extra relations among its parameters and reduce the number of them from eighteen down to five. In previous investigations, this can be done only down to nine. With another assumption among some of those parameters, the mass-matrix pattern is further simplified so as to be diagonalized analytically and in consequence four matrices which reveal S<sub>N</sub> symmetries among or between quark generations are obtained. In some of such S<sub>N</sub>-symmetric cases, the derived CKM matrices are complex which indicate that CP symmetry is violated accordingly. Taking the Jarlskog invariant as an estimate of the CPV strength, the value predicted by this model is orders stronger than the empirical value detected experimentally. However, that happens to fill partly the gap between the cosmologically observed amount of Baryon Asymmetry of the Universe (BAU) and that current Standard Model of particle physics predicts. It also proves the long suspected existence of BAU-productive eras in early universe if some fermions were indistinguishable, <em>i.e.</em>, S<sub>N</sub>-symmetric, under circumstances with extremely high temperatures.展开更多
文摘Nickel-rich cathode materials have attracted considerable interest because of their high specific capacities,voltage ranges,and low cost.However,serious capacity attenuation and poor rate performance limit their application.This study proposes a novel strategy to improve the cycle stability of the nickel-rich LiNi0.sCo0.1Mn0.1O2(NCM811)layer material by designing core-shell LiNio.sCoo.1 Mno.102(CS-NCM811).CS-NCM811 is designed by the characteristic reaction between dimethylglyoxime(C4H8N2O2)and nickel ion to form Ni(C4H7N2O2)2-The CS-NCM811 is characterized with high nickel content in its core and high manganese content on its surface,leading to a high capacity and excellent cycle stability.The capacity retention of CS-NCM811 was 72.8%,much higher than that of NCM811(47.1%)after 500 cycles at a rate of 5 C.Not only is this method a no vel strategy to desig n high capacity cathode materials but also provides some new in sights into the cycle stability of nickel-rich layered cathode materials.
基金the Engineering and Physical Sciences Research Council (EPSRC) for financial support through a Doctoral Prize Fellowship
文摘Nonequilibrium molecular dynamics(NEMD) simulations have provided unique insights into the nanoscale behaviour of lubricants under shear. This review discusses the early history of NEMD and its progression from a tool to corroborate theories of the liquid state, to an instrument that can directly evaluate important fluid properties, towards a potential design tool in tribology. The key methodological advances which have allowed this evolution are also highlighted. This is followed by a summary of bulk and confined NEMD simulations of liquid lubricants and lubricant additives, as they have progressed from simple atomic fluids to ever more complex, realistic molecules. The future outlook of NEMD in tribology, including the inclusion of chemical reactivity for additives, and coupling to continuum methods for large systems, is also briefly discussed.
基金supported by the Shenzhen Science and Technology Program(JCYJ20230808105111022,JCYJ20220818095806013)Natural Science Foundation of Guangdong(2023A1515012267)+1 种基金the National Natural Science Foundation of China(22178223)the Royal Society/NSFC cost share program(IEC\NSFC\223372).
文摘Low-electrode capacitive deionization(FCDI)is an emerging desalination technology with great potential for removal and/or recycling ions from a range of waters.However,it still suffers from inefficient charge transfer and ion transport kinetics due to weak turbulence and low electric intensity in flow electrodes,both restricted by the current collectors.Herein,a new tip-array current collector(designated as T-CC)was developed to replace the conventional planar current collectors,which intensifies both the charge transfer and ion transport significantly.The effects of tip arrays on flow and electric fields were studied by both computational simulations and electrochemical impedance spectroscopy,which revealed the reduction of ion transport barrier,charge transport barrier and internal resistance.With the voltage increased from 1.0 to 1.5 and 2.0 V,the T-CC-based FCDI system(T-FCDI)exhibited average salt removal rates(ASRR)of 0.18,0.50,and 0.89μmol cm^(-2) min^(-1),respectively,which are 1.82,2.65,and 2.48 folds higher than that of the conventional serpentine current collectors,and 1.48,1.67,and 1.49 folds higher than that of the planar current collectors.Meanwhile,with the solid content in flow electrodes increased from 1 to 5 wt%,the ASRR for T-FCDI increased from 0.29 to 0.50μmol cm^(-2) min^(-1),which are 1.70 and 1.67 folds higher than that of the planar current collectors.Additionally,a salt removal efficiency of 99.89%was achieved with T-FCDI and the charge efficiency remained above 95%after 24 h of operation,thus showing its superior long-term stability.
基金the financial support from EPSRC(EP/P024807/1,EP/M014045/1,EP/S000933/1 and EP/N009924/1)by the EPSRC energy storage for low carbon grids project(EP/K002252/1)+3 种基金the EPSRC Joint UK-India Clean Energy center(JUICE)(EP/P003605/1)the Integrated Development of Low-Carbon Energy Systems(IDLES)project(EP/R045518/1)the Innovate UK BAFTA project,the Innovate UK for Advanced Battery Lifetime Extension(ABLE)project for funding underthe China Scholarship Council。
文摘Mixed ionic electronic conductors(MIECs)have attracted increasing attention as anode materials for solid oxide fuel cells(SOFCs)and they hold great promise for lowering the operation temperature of SOFCs.However,there has been a lack of understanding of the performance-limiting factors and guidelines for rational design of composite metal-MIEC electrodes.Using a newly-developed approach based on 3 D-tomography and electrochemical impedance spectroscopy,here for the first time we quantify the contribution of the dual-phase boundary(DPB)relative to the three-phase boundary(TPB)reaction pathway on real MIEC electrodes.A new design strategy is developed for Ni/gadolinium doped ceria(CGO)electrodes(a typical MIEC electrode)based on the quantitative analyses and a novel Ni/CGO fiber-matrix structure is proposed and fabricated by combining electrospinning and tape-casting methods using commercial powders.With only 11.5 vol%nickel,the designer Ni/CGO fiber-matrix electrode shows 32%and 67%lower polarization resistance than a nano-Ni impregnated CGO scaffold electrode and conventional cermet electrode respectively.The results in this paper demonstrate quantitatively using real electrode structures that enhancing DPB and hydrogen kinetics are more efficient strategies to enhance electrode performance than simply increasing TPB.
文摘As both a beneficiary of global supply chain integration and a contributor to the creation of a new supply chain ecosystem,China is of immense importance to the growth of international supply chains.For example,it’s manufacturing industry is indispensable across every stage of the global supply chain from raw material to intermediate goods production and the assembly of finished products.And with a large consumer base,China has been the place where global goods and services are consumed.
文摘It is increasingly important to monitor sliding interfaces within machines,since this is where both energy is lost,and failures occur.Acoustic emission(AE)techniques offer a way to monitor contacts remotely without requiring transparent or electrically conductive materials.However,acoustic data from sliding contacts is notoriously complex and difficult to interpret.Herein,we simultaneously measure coefficient of friction(with a conventional force transducer)and acoustic emission(with a piezoelectric sensor and high acquisition rate digitizer)produced by a steel‒steel rubbing contact.Acquired data is then used to train machine learning(ML)algorithms(e.g.,Gaussian process regression(GPR)and support vector machine(SVM))to correlated acoustic emission with friction.ML training requires the dense AE data to first be reduced in size and a range of processing techniques are assessed for this(e.g.,down-sampling,averaging,fast Fourier transforms(FFTs),histograms).Next,fresh,unseen AE data is given to the trained model and the resulting friction predictions are compared with the directly measured friction.There is excellent agreement between the measured and predicted friction when the GPR model is used on AE histogram data,with root mean square(RMS)errors as low as 0.03 and Pearson correlation coefficients reaching 0.8.Moreover,predictions remain accurate despite changes in test conditions such as normal load,reciprocating frequency,and stroke length.This paves the way for remote,acoustic measurements of friction in inaccessible locations within machinery to increase mechanical efficiency and avoid costly failure/needless maintenance.
基金The authors would like to acknowledge the financial support of the EPSRC program Grant(EP/P012779/1).
文摘Artificial muscles are capable of generating actuation in microsystems with outstanding compliance.Recent years have witnessed a growing academic interest in artificial muscles and their application in many areas,such as soft robotics and biomedical devices.This paper aims to provide a comparative review of recent advances in artificial muscle based on various operating mechanisms.The advantages and limitations of each operating mechanism are analyzed and compared.According to the unique application requirements and electrical and mechanical properties of the muscle types,we suggest suitable artificial muscle mechanisms for specific microsystem applications.Finally,we discuss potential strategies for energy delivery,conversion,and storage to promote the energy autonomy of microrobotic systems at a system level.
基金Supported by The Breast Cancer Campaign and the Research Institute in Healthcare Sciences (Armesilla AL)The Wellcome Trust (Emerson M)
文摘Emerging evidence suggests that plasma membrane calcium ATPases (PMCAs) play a key role as regulators of calcium-triggered signal transduction pathways via interaction with partner proteins. PMCAs regulate these pathways by targeting specific proteins to cellular sub-domains where the levels of intracellular freecalcium are kept low by the calcium ejection properties of PMCAs. According to this model, PMCAs have been shown to interact functionally with the calcium-sensitive proteins neuronal nitric oxide synthase, calmodulindependent serine protein kinase, calcineurin and endothelial nitric oxidase synthase. Transgenic animals with altered expression of PMCAs are being used to evaluate the physiological significance of these interactions. To date, PMCA interactions with calcium-dependent partner proteins have been demonstrated to play a crucial role in the pathophysiology of the cardiovascular system via regulation of the nitric oxide and calcineurin/nuclear factor of activated T cells pathways. This new evidence suggests that PMCAs play a more sophisticated role than the mere ejection of calcium from the cells, by acting as modulators of signaling transduction pathways.
基金I.M.L.thanks La Caixa Foundation for funding a postgraduate scholarship(ID 100010434,fellowship code LCF/BQ/EU20/11810070)S.R.K.acknowledges the EPSRC Centre for Doctoral Training in the Advanced Characterisation of Materials(CDT-ACM)(EP/S023259/1)for funding a PhD studentship+2 种基金DOS acknowledges support from the EPSRC(EP/N01572X/1)and from the European Research Council,ERC(Grant No.758345)Via membership of the UK’s HEC Materials Chemistry Consortium,which is funded by the EPSRC(EP/L000202,EP/R029431,EP/T022213)this work used the UK Materials and Molecular Modelling(MMM)Hub(Thomas EP/P020194 and Young EP/T022213).
文摘Point defects are a universal feature of crystals.Their identification is addressed by combining experimental measurements with theoretical models.The standard modelling approach is,however,prone to missing the ground state atomic configurations associated with energy-lowering reconstructions from the idealised crystallographic environment.Missed ground states compromise the accuracy of calculated properties.To address this issue,we report an approach to navigate the defect configurational landscape using targeted bond distortions and rattling.Application of our workflow to eight materials(CdTe,GaAs,Sb_(2)S_(3),Sb_(2)Se_(3),CeO_(2),In_(2)O_(3),ZnO,anatase-TiO_(2))reveals symmetry breaking in each host crystal that is not found via conventional local minimisation techniques.The point defect distortions are classified by the associated physico-chemical factors.We demonstrate the impact of these defect distortions on derived properties,including formation energies,concentrations and charge transition levels.Our work presents a step forward for quantitative modelling of imperfect solids.
基金support from the European Union Horizon 2020 research and innovation programme,under the Marie Skłodowska-Curie grant agreement 706707the Engineering and Physical Sciences Research Council(EPSRC)grant no.EP/G037515/1+1 种基金the EPSRC Centre for Innovative Manufacturing in Large Area Electronics(CIM-LAE)grant no.EP/K03099X/1We also thank also Prof.Tobias Hertel for providing the PFO:(5,7)CNT material used in this work.D.D.C.B.further thanks the University of Oxford for financial support.
文摘Large-area manufacturing of flexible nanoscale electronics has long been sought by the printed electronics industry.However,the lack of a robust,reliable,high throughput and low-cost technique that is capable of delivering high-performance functional devices has hitherto hindered commercial exploitation.Herein we report on the extensive range of capabilities presented by adhesion lithography(a-Lith),an innovative patterning technique for the fabrication of coplanar nanogap electrodes with arbitrarily large aspect ratio.We use this technique to fabricate a plethora of nanoscale electronic devices based on symmetric and asymmetric coplanar electrodes separated by a nanogap<15 nm.We show that functional devices including self-aligned-gate transistors,radio frequency diodes and rectifying circuits,multi-colour organic light-emitting nanodiodes and multilevel non-volatile memory devices,can be fabricated in a facile manner with minimum process complexity on a range of substrates.The compatibility of the formed nanogap electrodes with a wide range of solution processable semiconductors and substrate materials renders a-Lith highly attractive for the manufacturing of large-area nanoscale opto/electronics on arbitrary size and shape substrates.
文摘Ball burnishing routine permits through a simple,fast and economical manner to obtain free chip on the manufactured parts.It generates a superior surface finish by rotating a ball tool against a workpiece.The burnishing process is commonly developed in industry in order to improve the surface quality,which is a critical issue in the manufacturing sector.An experimental study were carried out to determine the best surface quality for magnesium alloy subjected to d iff ere ni medium.Burnishing of magnesium alloy was performed varying four different mediums and combining different burnishing parameters.To design the experiment were used the classical Taguchi method through which were developed the L16 orthogonal array.This strategy allowed to detect the driving parameters that generate the best surface roughness value by computing the signal-to-noise ratio.The driving parameters values for this study are 400 N(force),0.05 mm/min(feed rate),three number of passes and boron oil as medium.The results are paramount important for designing heavy parts used in transportation vehicles such as automobiles,airplanes,high-speed trains etc.
基金M.P.,and W.L.C.acknowledge Discovery Grants DP110100713,DP140100883,DP120100170,and DP140100052the Melbourne Centre for Nanofabrication(MCN)in the Victorian Node of the Australian National Fabrication Facility(ANFF).D.Sikdar acknowledges Engineering and Physical Sciences Research Council UK’s funding scheme EP/L02098X/1.
文摘Surface-enhanced Raman scattering(SERS)substrates play important roles for the enhancement of inelastic scattering signals.Traditional substrates such as roughened electrodes and colloidal aggregates suffer from well-known signal reproducibility issues,whereas for current dominant two-dimensional planar systems,the hot spot distributions are limited by the zero-,one-or two-dimensional plane.The introduction of a three-dimensional(3D)system such as a pyramid geometry breaks the limitation of a single Cartesian SERS-active area and extends it into the z-direction,with the tip potentially offering additional benefits of strong field enhancement and high sensitivity.However,current 3D pyramidal designs are restricted to film deposition on prepared pyramid templates or self-assembly in pyramidal molds with spherical building blocks,hence limiting their SERS effectiveness.Here,we report on the fabrication of a new class of low cost and well-defined plasmonic nanoparticle pyramid arrays from different anisotropic shaped nanoparticles using combined top-down lithography and bottom-up self-assembly approach.These pyramids exhibit novel optical scattering properties that can be exploited for the design of reproducible and sensitive SERS substrate.The SERS intensity was found to decrease drastically in accordance with a power law function as the focal planes move from the apex of the pyramid structure towards the base.In comparison to sphere-based building blocks,pyramids assembled from anisotropic rhombic dodecahedral gold nanocrystals with numerous sharp tips exhibited the strongest SERS performance.Graphical Abstract Macroscale pyramidal array films with plasmonic tunability as a new class of SERS substrate for sensitive detection of chemicals.
文摘Color language has important meaning for children’s picture books.Understanding children’s preferences in terms of color language will be helpful when designers model computerized picture books in order to adapt to children’s visual senses and effectively stimulate children’s interest in reading.In this study,we aimed to further explore the general characteristics of children’s preference for colors,color depth and color matching forms in picture books.For the study,256 children between the ages of three and six were selected and divided into four groups.According to the implementation needs of the children’s color preference test,these childrenwere asked to complete a series of tasks so that their choices in the tasks could subsequently be analyzed.The tasks included making the following choices:selecting their preferred colors from nine options(red,orange,yellow,green,cyan,blue,purple,black and white);selecting their preferred color brightness fromthree different color shades;and indicating their preferences in relation to complementary colors,matching colors and pure colors.The experimental results showed that children aged between three and six mainly favor red,blue and yellow,and colors with a high degree of brightness.As children grow older,boys tend to prefer blue,and girls tend to prefer pink,with red remaining the favorite color of both genders.As for complementary colors,matching colors and solid colors,three-to six-year-old children prefer solid colors.In conclusion,it seems that color language preferences in children between the ages of three and six are very similar,which could be of use when designing children’s picture books to match their visual vocabulary and psychological cognition.
基金funded through ACORN,an EPSRC/DTi IMPACT-FARADAY partnershipThe support of Procter & Gamble is gratefully acknowledged
文摘Titanium dioxide was deposited from aqueous suspension onto cellulosic surfaces. Titania was sourced from Degussa （P25TM, 70：30 anatase：rutile）. Dry uptake of particles was shown to be rapid and dominant with one-third of the deposition occurring in less than 30 s and over one-half in the first minute. Isotherms were recorded to compare the rate of titanium deposition on dry and pre-wetted cotton. In the dry case uptake reached a maximum in 30 min whereas in the pre-wetted case the uptake was seen to continue beyond 180 min. A broad trend of higher deposition occurring at lower pH was seen, corresponding to the region where surface charges were opposite and thus attractive. Dry pickup was less significant at high pH. The response to varying ionic strength was complex and was attributed to the combined effect of charge screening, particle aggregation and consequent particle entrapment or occlusion. Titania deposition into the interstices of woven cotton sheets resulted in the formation of inorganic, nanoparticulate skeletons which could be isolated by controlled combustion of the cellulose and thus cotton was suggested to have potential for the templated synthesis of high surface area semiconductor materials.
基金This work was supported by the National Institute for Health Research Health Protection Research Unit(NIHR HPRU)[grant No.HPRU-2012-10047]in Healthcare Associated Infections and Antimicrobial Resistance at Imperial College London in partnership with Public Health England(PHE)ECS has received a Wellcome Trust ISFF Faculty postdoctoral fellowship,an Early Career Research Fellowship from the Antimicrobial Research Collaborative at Imperial College London,and acknowledges the support of the Florence Nightingale Foundation+2 种基金The views expressed are those of the author(s)and not necessarily those of the NHS,the NIHR,the Department of Health or Public Health EnglandThe funder of the study had no role in the study design,data collection,data analysis,data interpretation,or writing of the reportThe corresponding author had full access to all the data in the study and had final responsibility for the decision to submit for publication.
文摘Background:Poverty increases the risk of contracting infectious diseases and therefore exposure to antibiotics.Yet there is lacking evidence on the relationship between income and non-income dimensions of poverty and antimicrobial resistance.Investigating such relationship would strengthen antimicrobial stewardship interventions.Methods:A systematic review was conducted following Preferred Reporting Items for Systematic Reviews and Meta-Analyses(PRISMA)guidelines.PubMed,Ovid,MEDLINE,EMBASE,Scopus,CINAHL,PsychINFO,EBSCO,HMIC,and Web of Science databases were searched in October 2016.Prospective and retrospective studies reporting on income or non-income dimensions of poverty and their influence on colonisation or infection with antimicrobial-resistant organisms were retrieved.Study quality was assessed with the Integrated quality criteria for review of multiple study designs(ICROMS)tool.Results:Nineteen articles were reviewed.Crowding and homelessness were associated with antimicrobial resistance in community and hospital patients.In high-income countries,low income was associated with Streptococcus pneumoniae and Acinetobacter baumannii resistance and a seven-fold higher infection rate.In low-income countries the findings on this relation were contradictory.Lack of education was linked to resistant S.pneumoniae and Escherichia coli.Two papers explored the relation between water and sanitation and antimicrobial resistance in low-income settings.Conclusions:Despite methodological limitations,the results suggest that addressing social determinants of poverty worldwide remains a crucial yet neglected step towards preventing antimicrobial resistance.
文摘The stable isotope systems of the transition metals potentially provide constraints on the current and past operation of the biological pump,and on the state of ocean redox in Earth history.Here we focus on two exemplar metals,nickel(Ni)and zinc(Zn).The oceanic dissolved pool of both elements is isotopically heavier than the known inputs,implying an output with light isotope compositions.The modern oceanic cycle of both these elements is dominated by biological uptake into photosynthesised organic matter and output to sediment.It is increasingly clear,however,that such uptake is associated with only very minor isotope fractionation.We suggest that the isotopic balance is instead closed by the sequestration of light isotopes to sulphide in anoxic and organic-rich sediments,so that it is ocean chemistry that controls these isotope systems,and suggesting a different but equally interesting array of questions in Earth history that can be addressed with these systems.
文摘The book Yi Xue Shi(《医学史》History of Medicine)was written and edited by Cecilia Mettler and Fred Mettler couple,published in 1947.The book is about the literature research of systematic introduction to the history of medical development worldwide.The book provides a detailed description of the development of various medical disciplines and subjects through various documents and the authors and publication dates.Especially,Prof.Mettler has introduced the Chinese Yin and Yang(阴阳)and the five element theory(五行学说)and Shen Nung’s Materia Medica(神农本草)in this book.
基金financially supported by the National Natural Science Foundation of China(NSFC)[Grant No.51534009]National Key R&D Program of China[Grant No.2017YFB0306001]Natural Science Foundation of Hunan Province China(Grant No.2021JJ40750)。
文摘There is keen interest in using Ti alloys as lightweight structural materials for aerospace and automotive industries.However,a long-standing problem for these materials is their poor oxidation resistance.Herein,we designed and fabricated a Ti_(5)Si_(3) reinforced Ti-4(wt.%)Mo composite with two-scale network architecture by low energy milling and spark plasma sintering.It displays superior oxidation resistance at 800°C owing to the in-situ formation of a multi-component surface layer.This oxide layer has a dense grain size gradient structure that consists of an outer TiO_(2)layer and an inner SiO_(2)-padding-TiO_(2) layer,which has remarkable oxidation resistance and thermal stability.Furthermore,it was revealed that the hitherto unknown interaction between Ti_(5)Si_(3) reinforcement and nitrogen during oxidation would contribute to the formation of a TiN nano-twin interface layer,which accommodates the thermal mismatch strain between the oxide layer and matrix.This,along with high adhesion,confers excellent thermal cycling life with no cracking or spallation during long-term oxidation.In this regard,the secure operating temperature of this new composite can be increased to 800°C,which provides a design pathway for a new family of Ti matrix composites for high-temperature applications.
文摘In this manuscript, we present an explicit way to describe the violation of CP symmetry in the standard model (SM) of electrweak interactions. In such a way, complex Cabbibo-Kobayashi-Maskawa (CKM) matrices are achieved which stand for the violation of CP symmetry. At the beginning, two necessary but not sufficient conditions for yielding a complex CKM matrix are stated as criteria. Then we found an interesting condition between the real and imaginary parts of a Hermitian 3 × 3 matrix which may provide extra relations among its parameters and reduce the number of them from eighteen down to five. In previous investigations, this can be done only down to nine. With another assumption among some of those parameters, the mass-matrix pattern is further simplified so as to be diagonalized analytically and in consequence four matrices which reveal S<sub>N</sub> symmetries among or between quark generations are obtained. In some of such S<sub>N</sub>-symmetric cases, the derived CKM matrices are complex which indicate that CP symmetry is violated accordingly. Taking the Jarlskog invariant as an estimate of the CPV strength, the value predicted by this model is orders stronger than the empirical value detected experimentally. However, that happens to fill partly the gap between the cosmologically observed amount of Baryon Asymmetry of the Universe (BAU) and that current Standard Model of particle physics predicts. It also proves the long suspected existence of BAU-productive eras in early universe if some fermions were indistinguishable, <em>i.e.</em>, S<sub>N</sub>-symmetric, under circumstances with extremely high temperatures.
