Signal processing based research was adopted with Electroencephalogram(EEG)for predicting the abnormality and cerebral activities.The proposed research work is intended to provide an automatic diagnostic system to det...Signal processing based research was adopted with Electroencephalogram(EEG)for predicting the abnormality and cerebral activities.The proposed research work is intended to provide an automatic diagnostic system to determine the EEG signal in order to classify the brain function which shows whether a person is affected with schizophrenia or not.Early detection and intervention are vital for better prognosis.However,the diagnosis of schizophrenia still depends on clinical observation to date.Without reliable biomarkers,schizophrenia is difficult to detect in its early phase and hence we have proposed this idea.In this work,the EEG signal series are divided into non-linear feature mining,classification and validation,and t-test integrated feature selection process.For this work,19-channel EEG signals are utilized from schizophrenia class and normal pattern.Here,the datasets initially execute the splitting process based on raw 19-channel EEG into 6250 sample point’s sequences.With this process,1142 features of normal and schizophrenia class patterns can be obtained.In other hand,157 features from each EEG patterns are utilized based on Non-linear feature extraction process where 14 principal features can be identified in terms of considering the essential features.At last,the Deep Learning(DL)technique incorporated with an effective optimization technique is adopted for classification process called a Deep Convolutional Neural Network(DCNN)with mayfly optimization algorithm.The proposed technique is implemented into the platform of MATLAB in order to obtain better results and is analyzed based on the performance analysis framework such as accuracy,Signal to Noise Ratio(SNR),Mean Square Error,Normalized Mean Square Error(NMSE)and Loss.Through comparison,the proposed technique is proved to a better technique than other existing techniques.展开更多
In the scope of material science, it is well understood that mechanical behavior of a material is temperature dependent. The converse is also true and for specific loading cases contributes to a unique thermal failure...In the scope of material science, it is well understood that mechanical behavior of a material is temperature dependent. The converse is also true and for specific loading cases contributes to a unique thermal failure mechanism known as “heat explosion”. The goal for this paper is to improve the mathematical models for predicting heat explosion by using a specific case of the Fourier heat transfer system that focuses on thermoviscoelastic properties of materials. This is done by using a computational analysis to solve for an internal heat parameter that determines thermal failure at a critical value. This critical value is calculated under conditions either accounting for or negating the effect of heat dissipated by the material. This model is an improvement on existing models because it accounts for material specific properties and in doing so limits mathematical assumptions of the system. By limiting the assumptions in the conditions of the model, the model becomes more accurate and useful in regards to material design.展开更多
The global energy crisis and electricity shortage pose unprecedented challenges.Bio-based solar-driven ionic power generation devices with flexibility,photothermal self-healing and scalability hold great promise for s...The global energy crisis and electricity shortage pose unprecedented challenges.Bio-based solar-driven ionic power generation devices with flexibility,photothermal self-healing and scalability hold great promise for sustainable electricity and alleviating energy crisis.Here,inspired by plant transpiration,a multifunctional bio-based ion conductive elastomer with solar power generation capability was designed by engineered synergy among epoxy natural rubber,cellulose nanofibrils,lithium bis(trifluoromethane)sulfonimide and eumelanin.The film exhibits an outstanding stretchability(1072%)and toughness(22.7 MJ m^(-3)).The favorable synergy of low thermal conductivity,high hygroscopicity and photothermal conversion performance endowed the film with a large thermal gradient under light illumination,driving efficient water transpiration.Furthermore,the excellent interfacial compatibility between eumelanin and matrix facilitates the formation of space charge regions,which further enhances Li^(+)transport.The film demonstrates excellent evaporation rate(2.83 kg m^(-2)h^(-1)),output voltage(0.47 V)and conductivity(5.11×10^(-2)S m^(-1)).Notably,the film exhibits remarkable photothermal self-healing performance even in saline environment,achieving 99.6%healing efficiency of output voltage.Therefore,the film demonstrates significant prospects for applications in photo-thermoelectric generation and solar-driven ionic power generation.展开更多
This study investigates the effect of BaHfO_(3)(BHO)addition on the optical properties of YBa_2Cu_(3)O_(7-δ)(YBCO)superconducting thin films using spectroscopic ellipsometry.Through Raman spectroscopy and SEM analysi...This study investigates the effect of BaHfO_(3)(BHO)addition on the optical properties of YBa_2Cu_(3)O_(7-δ)(YBCO)superconducting thin films using spectroscopic ellipsometry.Through Raman spectroscopy and SEM analysis,optimal 10-min Ar ion etching effectively removes surface a-axis-oriented grains and Ba–Cu–O impurities,enhancing surface quality.Optical conductivity analysis reveals a doping-dependent evolution:10%BHO doping maximizes free carrier density and interband transition efficiency,attributed to optimized Cu–O bond contraction and reduced lattice distortions.Higher doping induces defect clustering,carrier scattering,and redshifted transitions due to lattice expansion.Dielectric function and loss function analyses confirm enhanced plasmonic behavior and flux pinning at 10%doping,while excessive doping degrades electronic transitions.These results highlight the critical role of controlled BHO addition and surface treatment in tailoring the optical and superconducting properties of YBCO,offering insights into the interplay among doping,carrier dynamics,and electronic structure in high-temperature superconductors(HTS).展开更多
The increasing demand in the diverse device applications of transparent conducting oxides (TCOs) requires synthesis of new TCOs of n- or p-type conductivity. This article is about materials engineering of ZnO-SnO2- ...The increasing demand in the diverse device applications of transparent conducting oxides (TCOs) requires synthesis of new TCOs of n- or p-type conductivity. This article is about materials engineering of ZnO-SnO2- In2O3-Ga2O3 to synthesize powders of the quaternary compound Zn2-xSn1-xlnxGaxO4-δ in the stoichiometry of x = 0.2, 0.3, and 0.4 by solid state reaction at 1275℃. Lattice parameters were determined by X-ray diffraction (XRD) technique and solubility of In3+ and Ga3+ in spinel Zn2SnO4 was found at 1275℃. The solubility limit of In3+ and Ga3+ in Zn2SnO4 is found at below x = 0.4. The optical transmittance approximated by the UV-Vis reflectance spectra showed excellent characteristics while optical band gap was consistent across 3.2 eV with slight decrease along increasing x value. Carrier mobility of the species was considerably higher than the older versions of zinc stannate spinel co-substitutions whereas the carrier concentrations were moderate.展开更多
Iron(Ⅱ) tetrasulfophthalocyanine(FeTSPc) ,as a novel mimetic enzyme of peroxidase,was used in the synthesis of a conducting polyaniline(PANI) /sodium dodecylsulfate(SDS) complex in SDS aqueous micellar solutions. The...Iron(Ⅱ) tetrasulfophthalocyanine(FeTSPc) ,as a novel mimetic enzyme of peroxidase,was used in the synthesis of a conducting polyaniline(PANI) /sodium dodecylsulfate(SDS) complex in SDS aqueous micellar solutions. The effects of pH,concentrations of aniline,SDS and H2O2,and reaction time on polymerization of aniline were studied in this case as shown by UV-Vis absorption spectroscopy. The results show that a wide range of pH(0.5-4.0) is required to produce the conducting PANI,and the optimal pH is 1.0 in SDS micelle. The optimal concentrations of aniline,SDS and H2O2 in feed,and reaction time in this case for the production of conducting PANI are respectively 10 mmol/L,10 mmol/L,25 mmol/L,and 15 h. FT-IR spectrum,elemental analysis,conductivity,cyclic voltammetry and thermogravimetric analysis confirm the thermal stability and electroactive form of PANI.展开更多
The polymer of complex [Ni(salen)], (N,N'-ethylenebis (salicylideneaminato) nickel(U)), was prepared on graphite electrode by the route of linear sweep potential method. The nano-micro sheaf/wire structures o...The polymer of complex [Ni(salen)], (N,N'-ethylenebis (salicylideneaminato) nickel(U)), was prepared on graphite electrode by the route of linear sweep potential method. The nano-micro sheaf/wire structures of poly[Ni(salen)] have been obtained by adjusting the polymerization sweep rate of 5, 20 and 40 mV.s-1. The polymer prepared at 20 mV.s-1 had nanoscaled wire structure of ca. 100 nm in diameter. The good electrochemical reversibility of poly[Ni(salen)] was investigated by cyclic voltammetry and galvanostatic test in 1.0 mol/L Et3MeNBF4/acetonitrile solution. The initial specific gravimetric capacitance of poly[Ni(salen)] at the current density of 0.1 mA·cm-2 reached 270.2 F·g-1, however, the cycle stability needs to be improved.展开更多
The gravitational instability of a thermally conducting self-gravitating system permeated by a uniform and oblique magnetic field has been analyzed in the framework of Tsallis’ nonextensive theory for possible mod-if...The gravitational instability of a thermally conducting self-gravitating system permeated by a uniform and oblique magnetic field has been analyzed in the framework of Tsallis’ nonextensive theory for possible mod-ifications in the Jeans’ instability criterion. It is concluded that the instability criterion is indeed modified into one that depends explicitly on the nonextensive parameter. The influence of thermal conductivity on the system stability is also examined.展开更多
Metal-organic frameworks(MOFs)have attracted significant interest as self-templates and precursors for the synthesis of carbon-based composites aimed at electromagnetic wave(EMW)absorption.However,the utilization of h...Metal-organic frameworks(MOFs)have attracted significant interest as self-templates and precursors for the synthesis of carbon-based composites aimed at electromagnetic wave(EMW)absorption.However,the utilization of high-temperature treatments has introduced uncertainties regarding the compositions and microstructures of resulting derivatives.Additionally,complete carbonization has led to diminished yields of the produced carbon composites,significantly limiting their practical applications.Consequently,the exploration of pristine MOF-based EMW absorbers presents an intriguing yet challenging endeavor,primarily due to inherently low electrical conductivity.In this study,we showcase the utilization of structurally robust Zr-MOFs as scaffolds to build highly conductive Zr-MOF/PPy composites via an inner-outer dual-modification approach,which involves the production of conducting polypyrrole(PPy)both within the confined nanoporous channels and the external surface of Zr-MOFs via post-synthetic modification.The interconnection of confined PPy and surface-lined PPy together leads to a consecutive and extensive conducting network to the maximum extent.This therefore entails outstanding conductivity up to~14.3 S cm^(-1) in Zr-MOF/PPy composites,which is approximately 1-2 orders of magnitude higher than that for conductive MOF nanocomposites constructed from either inner or outer modification.Benefiting from the strong and tunable conduction loss,as well as the induced dielectric polarization originated from the porous structures and MOF-polymer interfaces,Zr-MOF/PPy exhibits excellent microwave attenuation capabilities and a tunable absorption frequency range.Specifically,with only 15 wt.%loading,the minimum reflection loss(RLmin)can reach up to-67.4 dB,accompanied by an effective absorption bandwidth(EAB)extending to 6.74 GHz.Furthermore,the microwave absorption characteristics can be tailored from the C-band to the Ku-band by adjusting the loading of PPy.This work provides valuable insights into the fabrication of conductive MOF composites by presenting a straightforward pathway to enhance and reg-ulate electrical conduction in MOF-based nanocomposites,thus paving a way to facilely fabricate pristine MOF-based microwave absorbers.展开更多
Proton-conducting materials have attracted considerable interest because of their extensive application in energy storage and conversion devices.Among them,metal-organic frameworks(MOFs)present tremendous development ...Proton-conducting materials have attracted considerable interest because of their extensive application in energy storage and conversion devices.Among them,metal-organic frameworks(MOFs)present tremendous development potential and possibilities for constructing novel advanced proton conductors due to their special advantages in crystallinity,designability,and porosity.In particular,several special design strategies for the structure of MOFs have opened new doors for the advancement of MOF proton conductors,such as charged network construction,ligand functionalization,metal-center manipulation,defective engineering,vip molecule incorporation,and pore-space manipulation.With the implementation of these strategies,proton-conducting MOFs have developed significantly and profoundly within the last decade.Therefore,in this review,we critically discuss and analyze the fundamental principles,design strategies,and implementation methods targeted at improving the proton conductivity of MOFs through representative examples.Besides,the structural features,the proton conduction mechanism and the behavior of MOFs are discussed thoroughly and meticulously.Future endeavors are also proposed to address the challenges of proton-conducting MOFs in practical research.We sincerely expect that this review will bring guidance and inspiration for the design of proton-conducting MOFs and further motivate the research enthusiasm for novel proton-conducting materials.展开更多
Proton exchange membrane fuel cells (PEMFCs) provide an appealing sustainable energy system,with the solid-electrolyte membrane playing a crucial role in its overall performance.Currently,sulfonated poly(1,4-phenylene...Proton exchange membrane fuel cells (PEMFCs) provide an appealing sustainable energy system,with the solid-electrolyte membrane playing a crucial role in its overall performance.Currently,sulfonated poly(1,4-phenylene ether-ether sulfone)(SPEES),an aromatic hydrocarbon polymer,has garnered considerable attention as an alternative to Nafion polymers.However,the long-term durability and stability of SPEES present a significant challenge.In this context,we introduce a potential solution in the form of an additive,specifically a core–shell-based amine-functionalized iron titanate (A–Fe_(2)TiO_(5)),which holds promise for improving the lifetime,proton conductivity,and power density of SPEES in PEMFCs.The modified SPEES/A–Fe_(2)TiO_(5)composite membranes exhibited notable characteristics,including high water uptake,enhanced thermomechanical stability,and oxidative stability.Notably,the SPEES membrane loaded with 1.2 wt%of A–Fe_(2)TiO_(5)demonstrates a maximum proton conductivity of 155 mS ccm^(-1),a twofold increase compared to the SPEES membrane,at 80°C under 100%relative humidity (RH).Furthermore,the 1.2 wt%of A–Fe_(2)TiO_(5)/SPEES composite membranes exhibited a maximum power density of 397.37 mW cm^(-2)and a current density of 1148 mA cm^(-2)at 60°C under 100%RH,with an opencircuit voltage decay of 0.05 m V/h during 103 h of continuous operation.This study offers significant insights into the development and understanding of innovative SPEES nanocomposite membranes for PEMFC applications.展开更多
“Three-in-one”cathode,achieved via B-site heavy-doping of transition elements(typically Co,Fe)into proton-conductive perovskite,holds promise for enhancing the performance of proton-conducting solid oxide fuel cell(...“Three-in-one”cathode,achieved via B-site heavy-doping of transition elements(typically Co,Fe)into proton-conductive perovskite,holds promise for enhancing the performance of proton-conducting solid oxide fuel cell(H-SOFC)operated below 650℃for electricity generation.However,its electrochemical behavior above 650℃,essential for improving the efficiency of H-SOFC for fuel conversion,remains insufficiently explored.It is still challenging to propose guidance for the design of“threein-one”cathode toward optimal H-SOFC performance below and above 650℃,with the prerequisite of gaining a comprehensive understanding of the roles of Co and Fe in determining the H-SOFC performance.This work is to address this challenge.Through theoretical/experimental studies,Co is identified to play a role in improving the oxygen reduction reaction(ORR)activity while Fe plays a role in facilitating the cathode/electrolyte interfacial proton conduction.Therefore,if the operating temperature is above 650℃,lowering the Co/Fe ratio in“three-in-one”cathode becomes crucial since the limiting factor shifts from ORR activity to proton conduction.Implementing this strategy,the SOFC using BaCo_(0.15)-Fe_(0.55)Zr_(0.1)Y_(0.1)Yb_(0.1)O_(3−δ)cathode achieves peak power densities of 1.67Wcm^(−2)under H-SOFC mode at 700℃and 2.32Wcm^(−2)under dual ion-conducting SOFC mode at 750℃,which are the highest reported values so far.展开更多
The low lithium transference number of conventional dual-ion polymer electrolytes will lead to concentration polarization and lithium dendrite growth,thereby affecting the safety and cycling performance of lithium bat...The low lithium transference number of conventional dual-ion polymer electrolytes will lead to concentration polarization and lithium dendrite growth,thereby affecting the safety and cycling performance of lithium batteries.Herein,we report a flame-retardant polycarbonate-based single-ion conducting polymer electrolyte(PAGEC-B/PFN).Due to the immobilization of anions within the polycarbonate crosslinking network,PAGEC-B/PFN exhibits a high lithium transference number(0.86),which is beneficial for alleviating concentration polarization and suppressing the growth of lithium dendrite.With the assistance of the TEP flame retardant and FEC,as well as LiNO_(3) additives,PAGEC-B/PFN exhibits excellent flame retardancy,high ionic conductivity,and outstanding interfacial compatibility with the lithium metal anode.As expected,PAGEC-B/PFN achieves a high critical current density of up to 2.0 mA cm^(-2)and stable cycling of Li‖Li cell for over 2200 h.Meanwhile,LFP‖PAGEC-B/PFN‖Li cell delivers a specific capacity of 147.8 mA h g^(-1)at 0.5 C and exhibits excellent cycling performance over 600 cycles.This work provides a strategy for designing solid-state lithium batteries with high safety and high performance.展开更多
Scientific research is a journey into an uncharted territory.Researchers need to have the big picture for navigation and at the same time be detail-oriented,as details make a difference.Here I offer a few tips for con...Scientific research is a journey into an uncharted territory.Researchers need to have the big picture for navigation and at the same time be detail-oriented,as details make a difference.Here I offer a few tips for conducting research that I summarized based on my 30+years of research experience.展开更多
Pacing-induced cardiomyopathy (PICM) resultsf rom the detrimental effect of frequent right ventricular pacing.^([1]) The diagnosis relies on a combination of pacing-associated ventricular dyschrony manifested with ECG...Pacing-induced cardiomyopathy (PICM) resultsf rom the detrimental effect of frequent right ventricular pacing.^([1]) The diagnosis relies on a combination of pacing-associated ventricular dyschrony manifested with ECG wide LBBB-pattern QRS duration and clinical assessment, imaging studies. Conduction system pacing (CSP), such as His bundle pacing (HBP)and left bundle branch pacing (LBBP), may help to prevent PICM,^([2]) but the criteria for optimal patient selection remain inadequately defined.展开更多
This study addresses the challenge of high sintering temperatures in proton-conducting fuel cells(PCFCs)with BaCeO_(3)-doped electrolytes.We demonstrate that 1 mol%copper(Cu)doping at the B-site of BaCe_(0.7)Zr_(0.1)(...This study addresses the challenge of high sintering temperatures in proton-conducting fuel cells(PCFCs)with BaCeO_(3)-doped electrolytes.We demonstrate that 1 mol%copper(Cu)doping at the B-site of BaCe_(0.7)Zr_(0.1)(Dy_(0.1)|Yb_(0.1))_(0.2)O_(3-δ)(BCZDYb)improves sintering behavior,enabling densification at1400℃.However,Cu doping disrupts stoichiometry,creating barium vacancies and reducing protonaccepting cations,affecting overall conductivity.This mechanism is confirmed through density functional theory(DFT)calculations and various experimental techniques,including crystal structure analysis using X-ray diffraction(XRD)and morphology and elemental analysis via field emission scanning electron microscopy(FESEM)and energy-dispersive X-ray spectroscopy(EDS).Electrochemical measurements are performed using the electrochemical impedance spectroscopy(EIS).The ionic conductivity of1 mol%Cu-doped BCZDYb(BCZDYb-1)is 1.49×10^(-2)S cm^(-1)at 650℃,which is~3.58 times higher than that of BCZDYb sintered at 1200℃.The BCZDYb-1 exhibits~16 times higher grain boundary conductivity when sintered at 1400℃,compared to undoped BCZDYb.The single cell employing BCZDYb-1 as the electrolyte achieved a power density of~606 mW cm^(-2)at 550℃.These results indicate that a controlled amount of Cu doping can enhance densification while maintaining high ionic co nductivity,making it suitable for practical applications in PCFCs operating at lower temperatures.展开更多
An all-solid-state ion-selective electrode(ISE)for the detection of potassium ions in complex media was developed based on functional peptides with both antibacterial and antifouling properties.While exhibiting unique...An all-solid-state ion-selective electrode(ISE)for the detection of potassium ions in complex media was developed based on functional peptides with both antibacterial and antifouling properties.While exhibiting unique antifouling property,the ISE capitalized on the high surface area of the conductive metalorganic framework(MOF)solid transducer layer to facilitate rapid ion-electron transfer,consequently improving the electrode stability.For a short period,the application of a±1 n A current to the ISE resulted in a slight potential drift of 2.5μV/s,while for a long-term stability test,the ISE maintained a stable Nernstian response slope over 8 days.The antifouling and antibacterial peptide effectively eradicated bacteria from the electrode surface while inhibited the adhesion of bacteria and other biological organisms.Both theoretical calculations and experimental results indicated that the incorporation of peptides in the sensing membrane did not compromise the detection performance of the ISE.The prepared antifouling potassium ion-selective electrode exhibited a Nernstian response range spanning from 1.0×10^(–8)mol/L to 1.0×10–3mol/L,with a detection limit of 2.51 nmol/L.Crucially,the prepared solid-contact ISE maintained excellent antifouling and sensing capabilities in actual seawater and human urine,indicating a promising feasibility of this strategy for constructing ISEs suitable for practical application in complex systems.展开更多
The thermal conductivity of plasma-facing materials(PFM)exposed to intense radiation is a critical concern for the reliable usage of materials in fusion reactors.However,limited research has been performed regarding t...The thermal conductivity of plasma-facing materials(PFM)exposed to intense radiation is a critical concern for the reliable usage of materials in fusion reactors.However,limited research has been performed regarding the thermal conductivity of structures that rapidly change in a short time during collision cascade processes under irradiation.In this study,we employed the tight-binding(TB)method to investigate the electronic thermal conductivity(κ_(e))of tungsten-based systems during various cascading processes.We found thatκ_(e) values sharply decrease within the initial 0.3 picoseconds and then partially recover at a slow pace;this is closely linked to the evolution of defects and microstructural distortions.The increase in the initial kinetic energy of the primary knock-on atom and the presence of a high concentration of hydrogen atoms further decrease theκ_(e) values.Conversely,higher temperatures have a significant positive effect onκ_(e).Furthermore,the presence of a grain boundary∑5[001](130)substantially reducesκ_(e),whereas the absorption effect of point defects by the grain boundary has little influence onκ_(e) during cascades.Our findings provide a theoretical basis for evaluating changes in the thermal conductivity performance of PFMs during their usage in nuclear fusion reactors.展开更多
Aiming at the problem that the bit error rate(BER)of asymmetrically clipped optical orthogonal frequency division multiplexing(ACO-OFDM)space optical communication system is significantly affected by different turbule...Aiming at the problem that the bit error rate(BER)of asymmetrically clipped optical orthogonal frequency division multiplexing(ACO-OFDM)space optical communication system is significantly affected by different turbulence intensities,the deep learning technique is proposed to the polarization code decoding in ACO-OFDM space optical communication system.Moreover,this system realizes the polarization code decoding and signal demodulation without frequency conduction with superior performance and robustness compared with the performance of traditional decoder.Simulations under different turbulence intensities as well as different mapping orders show that the convolutional neural network(CNN)decoder trained under weak-medium-strong turbulence atmospheric channels achieves a performance improvement of about 10^(2)compared to the conventional decoder at 4-quadrature amplitude modulation(4QAM),and the BERs for both 16QAM and 64QAM are in between those of the conventional decoder.展开更多
An enhanced geothermal system(EGS)represents a promising approach to sustainable energy generation by harnessing subsurface heat from deep geological formations with low natural permeability.Sedimentary basins-such as...An enhanced geothermal system(EGS)represents a promising approach to sustainable energy generation by harnessing subsurface heat from deep geological formations with low natural permeability.Sedimentary basins-such as the Williston Basin in North Dakota-are considered viable candidates for EGS development due to their broad geographic extent and moderate geothermal potential.Notably,depleted or non-productive oil wells within these basins offer a cost-effective opportunity for EGS implementation as they can be repurposed,thereby significantly reducing the need for new drilling.This study evaluates the feasibility of EGS deployment in McKenzie County,North Dakota.Core samples from five partially abandoned or dry oil wells associated with production from the Red River Formation were obtained from the Core Library of the North Dakota Geological Survey.These samples,spanning the entire thickness of the formation,were sectioned and polished at defined depth intervals for detailed analyses and precise measurements of key reservoir properties critical to geothermal assessment.Several parameters were analyzed to assess the geothermal viability of these wells,including formation temperature,temperature gradient,porosity,thermal conductivity,energy storage potential,and estimated power output via the Organic Rankine Cycle(ORC).The results demonstrate significant depth-dependent variations in thermal and petrophysical properties.Specifically,the depth range of 4000-4500 m is identified as a promising target for EGS stimulation since it is characterized by elevated temperatures,high thermal conductivity,favorable temperature gradients,and sufficient porosity-all essential properties for enhancing permeability through hydraulic fracturing.Furthermore,the calculated energy content and potential ORC power output at these depths indicate that effective geothermal energy extraction is technically feasible.This suggests a compelling opportunity to repurpose existing fossil energy infrastructure-such as abandoned oil wells-for renewable geothermal applications.Overall,the findings of this study underscore the potential of sedimentary formations for EGS development and contribute to advancing low-carbon,diversified energy solutions in alignment with national decarbonization goals.展开更多
文摘Signal processing based research was adopted with Electroencephalogram(EEG)for predicting the abnormality and cerebral activities.The proposed research work is intended to provide an automatic diagnostic system to determine the EEG signal in order to classify the brain function which shows whether a person is affected with schizophrenia or not.Early detection and intervention are vital for better prognosis.However,the diagnosis of schizophrenia still depends on clinical observation to date.Without reliable biomarkers,schizophrenia is difficult to detect in its early phase and hence we have proposed this idea.In this work,the EEG signal series are divided into non-linear feature mining,classification and validation,and t-test integrated feature selection process.For this work,19-channel EEG signals are utilized from schizophrenia class and normal pattern.Here,the datasets initially execute the splitting process based on raw 19-channel EEG into 6250 sample point’s sequences.With this process,1142 features of normal and schizophrenia class patterns can be obtained.In other hand,157 features from each EEG patterns are utilized based on Non-linear feature extraction process where 14 principal features can be identified in terms of considering the essential features.At last,the Deep Learning(DL)technique incorporated with an effective optimization technique is adopted for classification process called a Deep Convolutional Neural Network(DCNN)with mayfly optimization algorithm.The proposed technique is implemented into the platform of MATLAB in order to obtain better results and is analyzed based on the performance analysis framework such as accuracy,Signal to Noise Ratio(SNR),Mean Square Error,Normalized Mean Square Error(NMSE)and Loss.Through comparison,the proposed technique is proved to a better technique than other existing techniques.
文摘In the scope of material science, it is well understood that mechanical behavior of a material is temperature dependent. The converse is also true and for specific loading cases contributes to a unique thermal failure mechanism known as “heat explosion”. The goal for this paper is to improve the mathematical models for predicting heat explosion by using a specific case of the Fourier heat transfer system that focuses on thermoviscoelastic properties of materials. This is done by using a computational analysis to solve for an internal heat parameter that determines thermal failure at a critical value. This critical value is calculated under conditions either accounting for or negating the effect of heat dissipated by the material. This model is an improvement on existing models because it accounts for material specific properties and in doing so limits mathematical assumptions of the system. By limiting the assumptions in the conditions of the model, the model becomes more accurate and useful in regards to material design.
基金financially supported by the National Natural Science Foundation of China(22175044)the Guangxi Natural Science Foundation(2023GXNSFDA026049)the Guangxi Major Talents Program(GXR-1BGQ2424023)。
文摘The global energy crisis and electricity shortage pose unprecedented challenges.Bio-based solar-driven ionic power generation devices with flexibility,photothermal self-healing and scalability hold great promise for sustainable electricity and alleviating energy crisis.Here,inspired by plant transpiration,a multifunctional bio-based ion conductive elastomer with solar power generation capability was designed by engineered synergy among epoxy natural rubber,cellulose nanofibrils,lithium bis(trifluoromethane)sulfonimide and eumelanin.The film exhibits an outstanding stretchability(1072%)and toughness(22.7 MJ m^(-3)).The favorable synergy of low thermal conductivity,high hygroscopicity and photothermal conversion performance endowed the film with a large thermal gradient under light illumination,driving efficient water transpiration.Furthermore,the excellent interfacial compatibility between eumelanin and matrix facilitates the formation of space charge regions,which further enhances Li^(+)transport.The film demonstrates excellent evaporation rate(2.83 kg m^(-2)h^(-1)),output voltage(0.47 V)and conductivity(5.11×10^(-2)S m^(-1)).Notably,the film exhibits remarkable photothermal self-healing performance even in saline environment,achieving 99.6%healing efficiency of output voltage.Therefore,the film demonstrates significant prospects for applications in photo-thermoelectric generation and solar-driven ionic power generation.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.52172271,12374378,52307026,and 52477022)the National Key Research and Development Program of China(Grant No.2022YFE03150200)Shanghai Science and Technology Innovation Program(Grant No.23511101600)。
文摘This study investigates the effect of BaHfO_(3)(BHO)addition on the optical properties of YBa_2Cu_(3)O_(7-δ)(YBCO)superconducting thin films using spectroscopic ellipsometry.Through Raman spectroscopy and SEM analysis,optimal 10-min Ar ion etching effectively removes surface a-axis-oriented grains and Ba–Cu–O impurities,enhancing surface quality.Optical conductivity analysis reveals a doping-dependent evolution:10%BHO doping maximizes free carrier density and interband transition efficiency,attributed to optimized Cu–O bond contraction and reduced lattice distortions.Higher doping induces defect clustering,carrier scattering,and redshifted transitions due to lattice expansion.Dielectric function and loss function analyses confirm enhanced plasmonic behavior and flux pinning at 10%doping,while excessive doping degrades electronic transitions.These results highlight the critical role of controlled BHO addition and surface treatment in tailoring the optical and superconducting properties of YBCO,offering insights into the interplay among doping,carrier dynamics,and electronic structure in high-temperature superconductors(HTS).
文摘The increasing demand in the diverse device applications of transparent conducting oxides (TCOs) requires synthesis of new TCOs of n- or p-type conductivity. This article is about materials engineering of ZnO-SnO2- In2O3-Ga2O3 to synthesize powders of the quaternary compound Zn2-xSn1-xlnxGaxO4-δ in the stoichiometry of x = 0.2, 0.3, and 0.4 by solid state reaction at 1275℃. Lattice parameters were determined by X-ray diffraction (XRD) technique and solubility of In3+ and Ga3+ in spinel Zn2SnO4 was found at 1275℃. The solubility limit of In3+ and Ga3+ in Zn2SnO4 is found at below x = 0.4. The optical transmittance approximated by the UV-Vis reflectance spectra showed excellent characteristics while optical band gap was consistent across 3.2 eV with slight decrease along increasing x value. Carrier mobility of the species was considerably higher than the older versions of zinc stannate spinel co-substitutions whereas the carrier concentrations were moderate.
基金Project(07JJ6020) supported by the Hunan Provincial Natural Science Foundation of ChinaProject(2007-24-3) supported by the Huaihua Key Science and Technology Program, China
文摘Iron(Ⅱ) tetrasulfophthalocyanine(FeTSPc) ,as a novel mimetic enzyme of peroxidase,was used in the synthesis of a conducting polyaniline(PANI) /sodium dodecylsulfate(SDS) complex in SDS aqueous micellar solutions. The effects of pH,concentrations of aniline,SDS and H2O2,and reaction time on polymerization of aniline were studied in this case as shown by UV-Vis absorption spectroscopy. The results show that a wide range of pH(0.5-4.0) is required to produce the conducting PANI,and the optimal pH is 1.0 in SDS micelle. The optimal concentrations of aniline,SDS and H2O2 in feed,and reaction time in this case for the production of conducting PANI are respectively 10 mmol/L,10 mmol/L,25 mmol/L,and 15 h. FT-IR spectrum,elemental analysis,conductivity,cyclic voltammetry and thermogravimetric analysis confirm the thermal stability and electroactive form of PANI.
基金supported by the Beijing Natural Science Foundation of China(No.2093039)Program for New Century Excellent Talents in Universities(NECT).
文摘The polymer of complex [Ni(salen)], (N,N'-ethylenebis (salicylideneaminato) nickel(U)), was prepared on graphite electrode by the route of linear sweep potential method. The nano-micro sheaf/wire structures of poly[Ni(salen)] have been obtained by adjusting the polymerization sweep rate of 5, 20 and 40 mV.s-1. The polymer prepared at 20 mV.s-1 had nanoscaled wire structure of ca. 100 nm in diameter. The good electrochemical reversibility of poly[Ni(salen)] was investigated by cyclic voltammetry and galvanostatic test in 1.0 mol/L Et3MeNBF4/acetonitrile solution. The initial specific gravimetric capacitance of poly[Ni(salen)] at the current density of 0.1 mA·cm-2 reached 270.2 F·g-1, however, the cycle stability needs to be improved.
文摘The gravitational instability of a thermally conducting self-gravitating system permeated by a uniform and oblique magnetic field has been analyzed in the framework of Tsallis’ nonextensive theory for possible mod-ifications in the Jeans’ instability criterion. It is concluded that the instability criterion is indeed modified into one that depends explicitly on the nonextensive parameter. The influence of thermal conductivity on the system stability is also examined.
基金supported by the Fundamental Research Funds for the Central Universities(Nos.2232023D-01 and 2232023D-07)the Shanghai Science&Technology Committee(No.22ZR1403300)the National Natural Science Foundation of China(No.52372040).
文摘Metal-organic frameworks(MOFs)have attracted significant interest as self-templates and precursors for the synthesis of carbon-based composites aimed at electromagnetic wave(EMW)absorption.However,the utilization of high-temperature treatments has introduced uncertainties regarding the compositions and microstructures of resulting derivatives.Additionally,complete carbonization has led to diminished yields of the produced carbon composites,significantly limiting their practical applications.Consequently,the exploration of pristine MOF-based EMW absorbers presents an intriguing yet challenging endeavor,primarily due to inherently low electrical conductivity.In this study,we showcase the utilization of structurally robust Zr-MOFs as scaffolds to build highly conductive Zr-MOF/PPy composites via an inner-outer dual-modification approach,which involves the production of conducting polypyrrole(PPy)both within the confined nanoporous channels and the external surface of Zr-MOFs via post-synthetic modification.The interconnection of confined PPy and surface-lined PPy together leads to a consecutive and extensive conducting network to the maximum extent.This therefore entails outstanding conductivity up to~14.3 S cm^(-1) in Zr-MOF/PPy composites,which is approximately 1-2 orders of magnitude higher than that for conductive MOF nanocomposites constructed from either inner or outer modification.Benefiting from the strong and tunable conduction loss,as well as the induced dielectric polarization originated from the porous structures and MOF-polymer interfaces,Zr-MOF/PPy exhibits excellent microwave attenuation capabilities and a tunable absorption frequency range.Specifically,with only 15 wt.%loading,the minimum reflection loss(RLmin)can reach up to-67.4 dB,accompanied by an effective absorption bandwidth(EAB)extending to 6.74 GHz.Furthermore,the microwave absorption characteristics can be tailored from the C-band to the Ku-band by adjusting the loading of PPy.This work provides valuable insights into the fabrication of conductive MOF composites by presenting a straightforward pathway to enhance and reg-ulate electrical conduction in MOF-based nanocomposites,thus paving a way to facilely fabricate pristine MOF-based microwave absorbers.
基金supported by the China Scholarship Council(No.202408120105)National Natural Science Foundation of China(32301530)+5 种基金Young Elite Scientist Sponsorship Program by CAST(No.YESS20230242)Tianjin Excellent Special Commissioner for Agricultural Science and Technology Project(23ZYCGSN00580)Natural Science Foundation of Tianjin(23JCZDJC00630)China Postdoctoral Science Foundation(2023M740563)State Key Laboratory of Pulp and Paper Engineering(202412,202413)the Central Publicinterest Scientific Institution Basa Research Fund(No.Y2022QC30).
文摘Proton-conducting materials have attracted considerable interest because of their extensive application in energy storage and conversion devices.Among them,metal-organic frameworks(MOFs)present tremendous development potential and possibilities for constructing novel advanced proton conductors due to their special advantages in crystallinity,designability,and porosity.In particular,several special design strategies for the structure of MOFs have opened new doors for the advancement of MOF proton conductors,such as charged network construction,ligand functionalization,metal-center manipulation,defective engineering,vip molecule incorporation,and pore-space manipulation.With the implementation of these strategies,proton-conducting MOFs have developed significantly and profoundly within the last decade.Therefore,in this review,we critically discuss and analyze the fundamental principles,design strategies,and implementation methods targeted at improving the proton conductivity of MOFs through representative examples.Besides,the structural features,the proton conduction mechanism and the behavior of MOFs are discussed thoroughly and meticulously.Future endeavors are also proposed to address the challenges of proton-conducting MOFs in practical research.We sincerely expect that this review will bring guidance and inspiration for the design of proton-conducting MOFs and further motivate the research enthusiasm for novel proton-conducting materials.
基金BK21 FOUR Program by Jeonbuk National University Research Grantsupported by “Regional Innovation Strategy (RIS)” through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (MOE)(2023RIS-008)H2KOREA funded by the Ministry of Education(2024 Hydrogen Industry-002, Innovative Human Resources Development Project for Hydrogen Industry)。
文摘Proton exchange membrane fuel cells (PEMFCs) provide an appealing sustainable energy system,with the solid-electrolyte membrane playing a crucial role in its overall performance.Currently,sulfonated poly(1,4-phenylene ether-ether sulfone)(SPEES),an aromatic hydrocarbon polymer,has garnered considerable attention as an alternative to Nafion polymers.However,the long-term durability and stability of SPEES present a significant challenge.In this context,we introduce a potential solution in the form of an additive,specifically a core–shell-based amine-functionalized iron titanate (A–Fe_(2)TiO_(5)),which holds promise for improving the lifetime,proton conductivity,and power density of SPEES in PEMFCs.The modified SPEES/A–Fe_(2)TiO_(5)composite membranes exhibited notable characteristics,including high water uptake,enhanced thermomechanical stability,and oxidative stability.Notably,the SPEES membrane loaded with 1.2 wt%of A–Fe_(2)TiO_(5)demonstrates a maximum proton conductivity of 155 mS ccm^(-1),a twofold increase compared to the SPEES membrane,at 80°C under 100%relative humidity (RH).Furthermore,the 1.2 wt%of A–Fe_(2)TiO_(5)/SPEES composite membranes exhibited a maximum power density of 397.37 mW cm^(-2)and a current density of 1148 mA cm^(-2)at 60°C under 100%RH,with an opencircuit voltage decay of 0.05 m V/h during 103 h of continuous operation.This study offers significant insights into the development and understanding of innovative SPEES nanocomposite membranes for PEMFC applications.
基金supported by the Natural Sciences and Engineering Research Council(NSERC)of Canada,Discovery Grant(GRPIN-2016-05494)Strategic Research Projects of Alberta Innovates Technology Futures(#G2016000655)funding from the Canada First Research Excellence Fund(CFREF-2015-00001).
文摘“Three-in-one”cathode,achieved via B-site heavy-doping of transition elements(typically Co,Fe)into proton-conductive perovskite,holds promise for enhancing the performance of proton-conducting solid oxide fuel cell(H-SOFC)operated below 650℃for electricity generation.However,its electrochemical behavior above 650℃,essential for improving the efficiency of H-SOFC for fuel conversion,remains insufficiently explored.It is still challenging to propose guidance for the design of“threein-one”cathode toward optimal H-SOFC performance below and above 650℃,with the prerequisite of gaining a comprehensive understanding of the roles of Co and Fe in determining the H-SOFC performance.This work is to address this challenge.Through theoretical/experimental studies,Co is identified to play a role in improving the oxygen reduction reaction(ORR)activity while Fe plays a role in facilitating the cathode/electrolyte interfacial proton conduction.Therefore,if the operating temperature is above 650℃,lowering the Co/Fe ratio in“three-in-one”cathode becomes crucial since the limiting factor shifts from ORR activity to proton conduction.Implementing this strategy,the SOFC using BaCo_(0.15)-Fe_(0.55)Zr_(0.1)Y_(0.1)Yb_(0.1)O_(3−δ)cathode achieves peak power densities of 1.67Wcm^(−2)under H-SOFC mode at 700℃and 2.32Wcm^(−2)under dual ion-conducting SOFC mode at 750℃,which are the highest reported values so far.
基金supported by the National Natural Science Foundation of China(22179149,22075329,51573215,and 21978332)Guangzhou Municipal Science and Technology Program(2025B01J2007,2025A03J4025,2025A03J4026)Fundamental Research Fund of Henan Academy of Sciences(232018002)。
文摘The low lithium transference number of conventional dual-ion polymer electrolytes will lead to concentration polarization and lithium dendrite growth,thereby affecting the safety and cycling performance of lithium batteries.Herein,we report a flame-retardant polycarbonate-based single-ion conducting polymer electrolyte(PAGEC-B/PFN).Due to the immobilization of anions within the polycarbonate crosslinking network,PAGEC-B/PFN exhibits a high lithium transference number(0.86),which is beneficial for alleviating concentration polarization and suppressing the growth of lithium dendrite.With the assistance of the TEP flame retardant and FEC,as well as LiNO_(3) additives,PAGEC-B/PFN exhibits excellent flame retardancy,high ionic conductivity,and outstanding interfacial compatibility with the lithium metal anode.As expected,PAGEC-B/PFN achieves a high critical current density of up to 2.0 mA cm^(-2)and stable cycling of Li‖Li cell for over 2200 h.Meanwhile,LFP‖PAGEC-B/PFN‖Li cell delivers a specific capacity of 147.8 mA h g^(-1)at 0.5 C and exhibits excellent cycling performance over 600 cycles.This work provides a strategy for designing solid-state lithium batteries with high safety and high performance.
文摘Scientific research is a journey into an uncharted territory.Researchers need to have the big picture for navigation and at the same time be detail-oriented,as details make a difference.Here I offer a few tips for conducting research that I summarized based on my 30+years of research experience.
文摘Pacing-induced cardiomyopathy (PICM) resultsf rom the detrimental effect of frequent right ventricular pacing.^([1]) The diagnosis relies on a combination of pacing-associated ventricular dyschrony manifested with ECG wide LBBB-pattern QRS duration and clinical assessment, imaging studies. Conduction system pacing (CSP), such as His bundle pacing (HBP)and left bundle branch pacing (LBBP), may help to prevent PICM,^([2]) but the criteria for optimal patient selection remain inadequately defined.
基金supported by the National Key Research and Development Program of China(2021YFB4001400)the Cooperation Project of Shan-dong Energy Group Co.,Ltd.(20200871)supported by 111 Project 2.0(BP0618008).
文摘This study addresses the challenge of high sintering temperatures in proton-conducting fuel cells(PCFCs)with BaCeO_(3)-doped electrolytes.We demonstrate that 1 mol%copper(Cu)doping at the B-site of BaCe_(0.7)Zr_(0.1)(Dy_(0.1)|Yb_(0.1))_(0.2)O_(3-δ)(BCZDYb)improves sintering behavior,enabling densification at1400℃.However,Cu doping disrupts stoichiometry,creating barium vacancies and reducing protonaccepting cations,affecting overall conductivity.This mechanism is confirmed through density functional theory(DFT)calculations and various experimental techniques,including crystal structure analysis using X-ray diffraction(XRD)and morphology and elemental analysis via field emission scanning electron microscopy(FESEM)and energy-dispersive X-ray spectroscopy(EDS).Electrochemical measurements are performed using the electrochemical impedance spectroscopy(EIS).The ionic conductivity of1 mol%Cu-doped BCZDYb(BCZDYb-1)is 1.49×10^(-2)S cm^(-1)at 650℃,which is~3.58 times higher than that of BCZDYb sintered at 1200℃.The BCZDYb-1 exhibits~16 times higher grain boundary conductivity when sintered at 1400℃,compared to undoped BCZDYb.The single cell employing BCZDYb-1 as the electrolyte achieved a power density of~606 mW cm^(-2)at 550℃.These results indicate that a controlled amount of Cu doping can enhance densification while maintaining high ionic co nductivity,making it suitable for practical applications in PCFCs operating at lower temperatures.
基金supported by the National Natural Science Foundation of China(Nos.22174082,22374085)the Key Research and Development Program of Shandong Province(No.2021ZDSYS30)Qingdao Postdoctoral Innovation Project Funding(No.QDBSH20220201038)。
文摘An all-solid-state ion-selective electrode(ISE)for the detection of potassium ions in complex media was developed based on functional peptides with both antibacterial and antifouling properties.While exhibiting unique antifouling property,the ISE capitalized on the high surface area of the conductive metalorganic framework(MOF)solid transducer layer to facilitate rapid ion-electron transfer,consequently improving the electrode stability.For a short period,the application of a±1 n A current to the ISE resulted in a slight potential drift of 2.5μV/s,while for a long-term stability test,the ISE maintained a stable Nernstian response slope over 8 days.The antifouling and antibacterial peptide effectively eradicated bacteria from the electrode surface while inhibited the adhesion of bacteria and other biological organisms.Both theoretical calculations and experimental results indicated that the incorporation of peptides in the sensing membrane did not compromise the detection performance of the ISE.The prepared antifouling potassium ion-selective electrode exhibited a Nernstian response range spanning from 1.0×10^(–8)mol/L to 1.0×10–3mol/L,with a detection limit of 2.51 nmol/L.Crucially,the prepared solid-contact ISE maintained excellent antifouling and sensing capabilities in actual seawater and human urine,indicating a promising feasibility of this strategy for constructing ISEs suitable for practical application in complex systems.
基金supported by the Collaborative Innovation Program of Hefei Science Center of CAS(No.2022HSC-CIP007)。
文摘The thermal conductivity of plasma-facing materials(PFM)exposed to intense radiation is a critical concern for the reliable usage of materials in fusion reactors.However,limited research has been performed regarding the thermal conductivity of structures that rapidly change in a short time during collision cascade processes under irradiation.In this study,we employed the tight-binding(TB)method to investigate the electronic thermal conductivity(κ_(e))of tungsten-based systems during various cascading processes.We found thatκ_(e) values sharply decrease within the initial 0.3 picoseconds and then partially recover at a slow pace;this is closely linked to the evolution of defects and microstructural distortions.The increase in the initial kinetic energy of the primary knock-on atom and the presence of a high concentration of hydrogen atoms further decrease theκ_(e) values.Conversely,higher temperatures have a significant positive effect onκ_(e).Furthermore,the presence of a grain boundary∑5[001](130)substantially reducesκ_(e),whereas the absorption effect of point defects by the grain boundary has little influence onκ_(e) during cascades.Our findings provide a theoretical basis for evaluating changes in the thermal conductivity performance of PFMs during their usage in nuclear fusion reactors.
基金supported by the National Natural Science Foundation of China(No.12104141).
文摘Aiming at the problem that the bit error rate(BER)of asymmetrically clipped optical orthogonal frequency division multiplexing(ACO-OFDM)space optical communication system is significantly affected by different turbulence intensities,the deep learning technique is proposed to the polarization code decoding in ACO-OFDM space optical communication system.Moreover,this system realizes the polarization code decoding and signal demodulation without frequency conduction with superior performance and robustness compared with the performance of traditional decoder.Simulations under different turbulence intensities as well as different mapping orders show that the convolutional neural network(CNN)decoder trained under weak-medium-strong turbulence atmospheric channels achieves a performance improvement of about 10^(2)compared to the conventional decoder at 4-quadrature amplitude modulation(4QAM),and the BERs for both 16QAM and 64QAM are in between those of the conventional decoder.
文摘An enhanced geothermal system(EGS)represents a promising approach to sustainable energy generation by harnessing subsurface heat from deep geological formations with low natural permeability.Sedimentary basins-such as the Williston Basin in North Dakota-are considered viable candidates for EGS development due to their broad geographic extent and moderate geothermal potential.Notably,depleted or non-productive oil wells within these basins offer a cost-effective opportunity for EGS implementation as they can be repurposed,thereby significantly reducing the need for new drilling.This study evaluates the feasibility of EGS deployment in McKenzie County,North Dakota.Core samples from five partially abandoned or dry oil wells associated with production from the Red River Formation were obtained from the Core Library of the North Dakota Geological Survey.These samples,spanning the entire thickness of the formation,were sectioned and polished at defined depth intervals for detailed analyses and precise measurements of key reservoir properties critical to geothermal assessment.Several parameters were analyzed to assess the geothermal viability of these wells,including formation temperature,temperature gradient,porosity,thermal conductivity,energy storage potential,and estimated power output via the Organic Rankine Cycle(ORC).The results demonstrate significant depth-dependent variations in thermal and petrophysical properties.Specifically,the depth range of 4000-4500 m is identified as a promising target for EGS stimulation since it is characterized by elevated temperatures,high thermal conductivity,favorable temperature gradients,and sufficient porosity-all essential properties for enhancing permeability through hydraulic fracturing.Furthermore,the calculated energy content and potential ORC power output at these depths indicate that effective geothermal energy extraction is technically feasible.This suggests a compelling opportunity to repurpose existing fossil energy infrastructure-such as abandoned oil wells-for renewable geothermal applications.Overall,the findings of this study underscore the potential of sedimentary formations for EGS development and contribute to advancing low-carbon,diversified energy solutions in alignment with national decarbonization goals.