Monolithic macroporous Pt/CeO2/Al2O3 catalysts were prepared using concentrated emulsions synthesis route, and the obtained samples were characterized with SEM, TG, TEM, XRD and TPR techniques. These monolithic cataly...Monolithic macroporous Pt/CeO2/Al2O3 catalysts were prepared using concentrated emulsions synthesis route, and the obtained samples were characterized with SEM, TG, TEM, XRD and TPR techniques. These monolithic catalysts were applied to water gas shift (WGS) reaction in reformed gases. The SEM and TEM results indicated that the monoliths possessed macroporosity, and that the platinum particles homogeneously dispersed on the supports with the particle size in the range of 1-2 nm. The reducibility of the catalysts was characterized by TPR method, and it was shown that the monolithic PtOx/CeO2/Al2O3 exhibited the similar reducibility property to that of the particle PtOx/CeO2 reported in literatures. The CO conversion over the monolithic catalysts is higher than that over micro-reactor catalysts for WGS reaction in the reformed gases conditions, indicating that the monolithic macroporous catalysts is a potential new route for miniaturization of WGS reactor.展开更多
Based on previous work, a novel Frequency Selective Surface (FSS) consisting of two metallic layers is proposed. The first layer is inductive-designed to generate the band-pass performance, while the second layer is c...Based on previous work, a novel Frequency Selective Surface (FSS) consisting of two metallic layers is proposed. The first layer is inductive-designed to generate the band-pass performance, while the second layer is capacitive-designed so that the miniaturization characteristic can be further improved. As a result, compared with the traditional single-layer structure, the profile of the FSS proposed is relatively small with the cell’s dimension only 0.0814λ × 0.0814λ. Moreover, the structure’s stability corresponding to waves of different polarizations and incident angles are also testified, which ensures the practicability of the proposed structure.展开更多
Since the discovery of mesoporous silica in 1990s,there have been numerous mesoporous silica-based nanomaterials developed for catalytic applications,aiming at enhanced catalytic activity and stability.Recently,there ...Since the discovery of mesoporous silica in 1990s,there have been numerous mesoporous silica-based nanomaterials developed for catalytic applications,aiming at enhanced catalytic activity and stability.Recently,there have also been considerable interests in endowing them with hierarchical porosities to overcome the diffusional limitation for those with long unimodal channels.Present processes of making mesoporous silica largely rely on chemical sources which are relatively expensive and impose environmental concerns on their processes.In this regard,it is desirable to develop hierarchical silica supports from natural minerals.Herein,we present a series of work on surface reconstruction,modification,and functionalization to produce diatomite-based catalysts with original morphology and macro-meso-micro porosities and to test their suitability as catalyst supports for both liquid-and gas-phase reactions.Two wet-chemical routes were developed to introduce mesoporosity to both amorphous and crystalline diatomites.Importantly,we have used computational modeling to affirm that the diatomite morphology can improve catalytic performance based on fluid dynamics simulations.Thus,one could obtain this type of catalysts from numerous natural diatoms that have inherently intricate morphologies and shapes in micrometer scale.In principle,such catalytic nanocomposites acting as miniaturized industrial catalysts could be employed in microfluidic reactors for process intensification.展开更多
An uncommon fractal construction method is applied in the microwave element design. A novel fractal defected ground structure (DGS) based on micro electro-mechanical system (MEMS) is proposed. The size of this nov...An uncommon fractal construction method is applied in the microwave element design. A novel fractal defected ground structure (DGS) based on micro electro-mechanical system (MEMS) is proposed. The size of this novel fractal DGS can achieve 86% size reduction compared with the conventional dumbbell type DGS. This novel fractal DGS is used in the miniaturization design of L-band microstrip antenna array. The simulation result shows that this novel fractal DGS can effectively reduce the mutual coupling between the antenna elements, so it is helpful to the miniaturization of microstrip array, namely the approximately same gain value can be achieved with the shorter distance between elements.展开更多
Miniaturization and compact printed planar monopole antenna coplanar Waveguide CPW/microstrip feed line three half semi-circular (3HSC) with similar ground plane is presented, design, simulation, fabrication and tes...Miniaturization and compact printed planar monopole antenna coplanar Waveguide CPW/microstrip feed line three half semi-circular (3HSC) with similar ground plane is presented, design, simulation, fabrication and tested experimentally for Ultra-Wideband (UWB) eommnnication application especially for WLAN and HIPERLAN/2 WLAN. The antenna design has a far from the traditional antennas such as a rectangular, circular, elliptical etc. Generating original planar antenna has been investigated to be an effect the combine geometry shapes of the radiation element part with the same geometry shapes of the slots in the ground plane. The simulation and measuring results have a good agreement, large bandwidth and radiation pattern behavior an omni-directional with stable gain has been obtained.展开更多
The miniaturization and endurance of wearable devices have been the research direction for a long time.With the development of nanotechnology and the emergence of microelectronics products,people have explored many ne...The miniaturization and endurance of wearable devices have been the research direction for a long time.With the development of nanotechnology and the emergence of microelectronics products,people have explored many new strategies that may be applied to wearable devices.In this overview,we will summarize the recent research of wearable devices in these two directions,and summarize some available related technologies.展开更多
Magnetic,dielectric and DC conductive properties of Ni_(0.95-x)Zn_(x)Co_(0.05)Fe_(1.90)Mn_(0.02)O_(4)(with x=0-0.20 at an interval of 0.05)ferrite ceramics were studied,in order to develop magneto-dielectric materials...Magnetic,dielectric and DC conductive properties of Ni_(0.95-x)Zn_(x)Co_(0.05)Fe_(1.90)Mn_(0.02)O_(4)(with x=0-0.20 at an interval of 0.05)ferrite ceramics were studied,in order to develop magneto-dielectric materials with almost equal values of relative permeability and permittivity,for the miniaturization of HF(3-30 MHz)and VHF(30-90MHz and 100-300 MHz)antennas.The ferrite ceramics were prepared by using the conventional two-step sintering process.The real part of relative permeability is increased almost linearly with increasing concentration of Zn,while that of relative permittivity keeps nearly unchanged.It is found that promising magneto-dielectric materials,with close values of real permeability and permittivity over 30-90 MHz(VHF),can be obtained for the samples at Zn concentrations between x=0.05 and x=0.10.展开更多
Piezoelectric ceramics with high mechanical quality factor Q_(m) and large piezoelectric coefficient d_(33) are urgently required for advanced piezoelectric applications.However,obtaining both of these prop-erties sim...Piezoelectric ceramics with high mechanical quality factor Q_(m) and large piezoelectric coefficient d_(33) are urgently required for advanced piezoelectric applications.However,obtaining both of these prop-erties simultaneously remains a difficult challenge due to their mutually restrictive relationship.Here 0.5Pb(Ni_(1/3)Nb_(2/3))O_(3)-0.5Pb(Zr_(0.3)Ti_(0.7))O_(3) piezoceramic with tetragonal(T)-rich MPB is designed as a matrix to construct the defect engineering by doping low-valent Mn ions.The strong coupling of defect dipole and T-rich phase can effectively hinder the rotation of P_(s),restrict domain wall motion and improve Q_(m).At the same time,the substituted Mn ions will introduce local random field,destroying the long-range or-dering of ferroelectric domain and reducing domain size.The miniaturized domain structure can increase poling efficiency and inhibit the reduction of d_(33).Guided by this strategy,Q_(m) has increased by more than 10 times and d_(33) has only decreased by about 25%.The optimized electromechanical performance with Q_(m)=822,d_(33)=502 pC/N,k_(p)=0.55 and tanδ=0.0069 can be obtained in the present study.展开更多
The miniaturized broadband detection module can be embedded into the microwave application system such as the front end of the transmitter to detect the power or other parameters in real time.It is highly prospective ...The miniaturized broadband detection module can be embedded into the microwave application system such as the front end of the transmitter to detect the power or other parameters in real time.It is highly prospective in military and scientific research.In this paper,a broadband power detection module operating at 26.5 GHz-40.0 GHz is designed by using low-barrier Schottky diode as the detector and a comparator for threshold output.This module can dynamically detect the power range between-10 dBm and 10 dBm with the detection accuracy of 0.1 dB.Further,the temperature compensation circuit is also applied to improve the measurement error.As a result,the resulted error low to±1 dB in the temperature range of -55℃ to +85℃ is achieved.The designed module is encapsulated by a Kovar alloy with a small volume of 9 mm×6 mm×3 mm.This endows the designed module the advantages of small size,easy integration,and low cost,and even it is applicable to high-reliability environments such as satellites.展开更多
Bromodomain and plant homeodomain(PHD)finger containing protein 1(Brpf1)is an activator and scaffold protein of a multiunit complex that includes other components involving lysine acetyltransferase(KAT)6A/6B/7.Brpf1,K...Bromodomain and plant homeodomain(PHD)finger containing protein 1(Brpf1)is an activator and scaffold protein of a multiunit complex that includes other components involving lysine acetyltransferase(KAT)6A/6B/7.Brpf1,KAT6A,and KAT6B mutations were identified as the causal genes of neurodevelopmental disorders leading to intellectual disability.Our previous work revealed strong and specific expression of Brpf1 in both the postnatal and adult forebrain,especially the hippocampus,which has essential roles in learning and memory.Here,we hypothesized that Brpf1 plays critical roles in the function of forebrain excitatory neurons,and that its deficiency leads to learning and memory deficits.To test this,we knocked out Brpf1 in forebrain excitatory neurons using CaMKIIa-Cre.We found that Brpf1 deficiency reduced the frequency of miniature excitatory postsynaptic currents and downregulated the expression of genes Pcdhgb1,Slc16a7,Robo3,and Rho,which are related to neural development,synapse function,and memory,thereby damaging spatial and fear memory in mice.These findings help explain the mechanisms of intellectual impairment in patients with BRPF1 mutation.展开更多
Tunable Airy beams with controllable propagation trajectories have sparked interest in various fields,such as optical manipulation and laser fabrication.Existing research approaches encounter challenges related to ins...Tunable Airy beams with controllable propagation trajectories have sparked interest in various fields,such as optical manipulation and laser fabrication.Existing research approaches encounter challenges related to insufficient compactness and integration feasibility,or they require enhanced tunability to enable real-time dynamic manipulation of the propagation trajectory.In this work,we present a novel method that utilizes a dual metasurface system to surpass these limitations,significantly enhancing the practical potential of the Airy beam.Our approach involves encoding a cubic phase profile and two off-axis Fresnel lens phase profiles across the two metasurfaces.The validity of the proposed strategy has been confirmed through simulation and experimental results.The proposed meta-device addresses the existing limitations and lays the foundation for broadening the applicability of Airy beams across diverse domains,encompassing light-sheet microscopy,laser fabrication,optical tweezers,etc.展开更多
Miniature devices comprising stimulus-responsive hydrogels with high environmental adaptability are now considered competitive candidates in the fields of biomedicine,precise sensors,and tunable optics.Reliable and ad...Miniature devices comprising stimulus-responsive hydrogels with high environmental adaptability are now considered competitive candidates in the fields of biomedicine,precise sensors,and tunable optics.Reliable and advanced fabricationmethods are critical formaximizing the application capabilities ofminiature devices.Light-based three-dimensional(3D)printing technology offers the advantages of a wide range of applicable materials,high processing accuracy,and strong 3D fabrication capability,which is suitable for the development of miniature devices with various functions.This paper summarizes and highlights the recent advances in light-based 3D-printed miniaturized devices,with a focus on the latest breakthroughs in lightbased fabrication technologies,smart stimulus-responsive hydrogels,and tunable miniature devices for the fields of miniature cargo manipulation,targeted drug and cell delivery,active scaffolds,environmental sensing,and optical imaging.Finally,the challenges in the transition of tunable miniaturized devices from the laboratory to practical engineering applications are presented.Future opportunities that will promote the development of tunable microdevices are elaborated,contributing to their improved understanding of these miniature devices and further realizing their practical applications in various fields.展开更多
Background:To explore potential biomarkers for early diagnosis of atherosclerosis(AS)and provide basic data for further research on AS,the characteristics of serum metabolomics during the progression of AS in mini-pig...Background:To explore potential biomarkers for early diagnosis of atherosclerosis(AS)and provide basic data for further research on AS,the characteristics of serum metabolomics during the progression of AS in mini-pigs were observed dynamically.Methods:An AS model in Bama miniature pigs was established by a high-cholesterol and high-fat diet.Fasting serum samples were collected monthly for metabolomics and serum lipid detection.At the end of the treatment period,pathological analysis of the abdominal aorta and coronary artery was performed to evaluate the lesions of AS,thereby distinguishing the susceptibility of mini-pigs to AS.The metabolomics was de-tected using a high-resolution untargeted metabolomic approach.Statistical analysis was used to identify metabolites associated with AS susceptibility.Results:Based on pathological analysis,mini-pigs were divided into two groups:a susceptible group(n=3)and a non-susceptible group(n=6).A total of 1318 metabo-lites were identified,with significant shifting of metabolic profiles over time in both groups.Dynamic monitoring analysis highlighted 57 metabolites that exhibited an ob-vious trend of differential changes between two groups with the advance of time.The KEGG(Kyoto Encyclopedia of Genes and Genomes)pathway enrichment analysis in-dicated significant disorders in cholesterol metabolism,primary bile acid metabolism,histidine metabolism,as well as taurine and hypotaurine metabolism.Conclusions:During the progression of AS in mini-pigs induced by high-cholesterol/high-fat diet,the alterations in serum metabolic profile exhibited a time-dependent pattern,accompanied by notable disturbances in lipid metabolism,cholesterol me-tabolism,and amino acid metabolism.These metabolites may become potential bio-markers for early diagnosis of AS.展开更多
Energetic Semiconductor bridge(ESCB)based on reactive multilayered films(RMFs)has a promising application in the miniature and intelligence of initiator and pyrotechnics device.Understanding the ignition enhancement m...Energetic Semiconductor bridge(ESCB)based on reactive multilayered films(RMFs)has a promising application in the miniature and intelligence of initiator and pyrotechnics device.Understanding the ignition enhancement mechanism of RMFs on semiconductor bridge(SCB)during the ignition process is crucial for the engineering and practical application of advanced initiator and pyrotechnics devices.In this study,a one-dimensional(1D)gas-solid two-phase flow ignition model was established to study the ignition process of ESCB to charge particles based on the reactivity of Al/MoO_(3) RMFs.In order to fully consider the coupled exothermic between the RMFs and the SCB plasma during the ignition process,the heat release of chemical reaction in RMFs was used as an internal heat source in this model.It is found that the exothermal reaction in RMFs improved the ignition performance of SCB.In the process of plasma rapid condensation with heat release,the product of RMFs enhanced the heat transfer process between the gas phase and the solid charge particle,which accelerated the expansion of hot plasma,and heated the solid charge particle as well as gas phase region with low temperature.In addition,it made up for pressure loss in the gas phase.During the plasma dissipation process,the exothermal chemical reaction in RMFs acted as the main heating source to heat the charge particle,making the surface temperature of the charge particle,gas pressure,and gas temperature rise continuously.This result may yield significant advantages in providing a universal ignition model for miniaturized ignition devices.展开更多
Pig models are widely used in otological research. The establishment of common pig and miniature pig animal models has opened up new fields in otological research and is also an ideal large otological animal model. Th...Pig models are widely used in otological research. The establishment of common pig and miniature pig animal models has opened up new fields in otological research and is also an ideal large otological animal model. This article introduces the applications, current status, progress, advantages, and issues of using pigs as otologic animal models. It summarizes current research on pigs in the fields of hearing disorders, otitis, vertigo, cochlea, gene editing, and tissue engineering, among other otologic and audiological areas. These models are valuable for translating basic medical science into clinical applications. Based on this, platforms have been established for studying deafness and vertigo, cochlear implantation experiments, stem cell and gene therapy, and tissue engineering. These serve as ideal experimental models for the prevention and treatment of ear diseases, pointing toward new directions. This will bolster the promotion and application of pig models in the fields of tissue engineering and gene editing in the future.展开更多
The putative causes of bruxism are multifactorial and there are no definite measures for bruxism management.The aim of this study was to evaluate the efficacy of biofeedback therapy on sleep bruxism,compared with occl...The putative causes of bruxism are multifactorial and there are no definite measures for bruxism management.The aim of this study was to evaluate the efficacy of biofeedback therapy on sleep bruxism,compared with occlusal splint.Twenty-four volunteers with sleep bruxism were divided into two groups:the GTB group that were treated with biofeedback therapy(n 512) and the GTO group that were treated with occlusal splint(n 512).A mini pressure sensor integrated with a monitoring circuit by use of a maxillary biofeedback splint was fabricated.To foster the relaxation of the masticatory muscles and the nervous system,the wireless device received signals from bruxism events and vibrations alerted the bruxer when the threshold was exceeded.Total episodes and average duration of bruxism events during8 hours of sleep were analyzed with the monitoring program(TRMY1.0).After 6 and 12 weeks,the episodes(P 50.001) and duration(P,0.05) in the GTB group declined dramatically.In contrast,there were no significant differences in the GTO group after the treatment(P.0.05).Furthermore,the episodes had significant differences between the GTB group and the GTO group after the same period of treatment(P 5 0.000).The results suggest that biofeedback therapy may be an effective and convenient measure for mild bruxers,when compared with occlusal splint therapy.The mini wireless biofeedback method may be of value for the diagnosis and management of bruxism in the future.展开更多
Electrical sensing systems, such as those involving eutectic salt, are mostly used in connection to leakage from existing airborne high-temperature air-conducting pipelines. Such complex structured systems are suscept...Electrical sensing systems, such as those involving eutectic salt, are mostly used in connection to leakage from existing airborne high-temperature air-conducting pipelines. Such complex structured systems are susceptible to external interferences and, thus, cannot meet the increasingly strict monitoring needs of a complex air-conducting pipeline system of an aircraft. In view of this point, this paper studies an alternative sensor system based on a dense array fiber grating. To obtain a compact and light-weight airborne signal processing system, a field programmable gate array is used as the main control core that controls the output of the light source. The functions of pulse modulation, analog-to-digital conversion,data buffering and transmission are integrated into a single system, while the linear sensing monitoring is obtained by detecting the time-division and wavelength-division wavelength drift signals of the fiber Bragg grating array. Our experiments show that the spatial resolution of the linear sensing system approaches 5 cm, the temperature measurement accuracy reaches 2 ℃, the temperature measurement range is between 0–250 ℃, and the response time is within 4 s. Compared with the existing electrical monitoring systems, various monitoring indicators have been greatly improved and have broad application prospects.展开更多
A miniature thermoacoustic prime mover, consuming heat to radiate sound, may be considered as a potential way of heat management in microcircuits because of its simplicity and stability. A prototype with variable reso...A miniature thermoacoustic prime mover, consuming heat to radiate sound, may be considered as a potential way of heat management in microcircuits because of its simplicity and stability. A prototype with variable resonant tube length of 10 to 25 cm was built, and experiments were carried out to observe its performance, such as onset temperature, oscillation amplitude and operating frequency. The results with atmospheric air showed that proper structures and operating conditions can make the system start an oscillation at a temperature lower than 100 ℃, which proves the feasibility of potential usage in electronic units. The influences of stack position, heat input power or tube inclination on the oscillation amplitude, onset temperature and operating frequency are also presented.展开更多
Due to the further intense human urbanization and industrialization,the environmental problems and climate changes became global issues that we have to face today.Like increasing environmental pollutants,ocean eutroph...Due to the further intense human urbanization and industrialization,the environmental problems and climate changes became global issues that we have to face today.Like increasing environmental pollutants,ocean eutrophication,red-tide and acidification are causing irrevocably damages to the marine ecological environment.As an important part of marine ecosystem,macrobenthos plays an essential role in energy flow and substance circulation in the marine ecosystem.Therefore,the study of macrobenthic community structures and diversities were necessary,meanwhile the protection of macrobenthic diversity was also a tough problem.In recent years,many researches were mainly focus on Jiaozhou Bay of the Yellow Sea,the Yangtze Estuary,the coastal of Zhejiang and Fujian Provinces,while seldom on benthic organisms in the Bohai Sea.In this paper,the community structures and diversities of the common macrobenthos in the Bohai Sea were introduced and the macrobenthic response to environmental changes and environmental pollution caused by the construction of the Bohai Sea were also mentioned.The results showed that the large benthic fauna in th Bohai Sea was relatively simple compared to other China seas.There were about 400 species of large benthic organisms.The dominant species were low temperature and wide salt warm water.In the last five years,the annual average biomass was 23.82 g/m^2 and the annual average density was 1498 ind/m^2.The seasonal variation of average habitat density was usually summer autumn spring winter,and the average biomass was usually autumn spring summer winter.Original communities were destroyed and the dominant species appeared to be miniaturized caused by abuse of marine resources.Since the 21st century,the number of crustacean arthropods,bivalve molluscs,and echinoderms have decreased rapidly,but the number of polychaetes and small molluscs increased gradually.With the development of the comprehensive ecological management of the Bohai Sea,the ecological environment and habitat status in the studied area were remedied and improved.Afterwards,the trend of miniaturization was also suppressed.The results of this study presented some existed problems about marine ecological survey and provided some reasonable suggestions for the rational utilization and protection of marine resources.展开更多
Emerging memristive devices offer enormous advantages for applications such as non-volatile memories and inmemory computing(IMC),but there is a rising interest in using memristive technologies for security application...Emerging memristive devices offer enormous advantages for applications such as non-volatile memories and inmemory computing(IMC),but there is a rising interest in using memristive technologies for security applications in the era of internet of things(IoT).In this review article,for achieving secure hardware systems in IoT,lowpower design techniques based on emerging memristive technology for hardware security primitives/systems are presented.By reviewing the state-of-the-art in three highlighted memristive application areas,i.e.memristive non-volatile memory,memristive reconfigurable logic computing and memristive artificial intelligent computing,their application-level impacts on the novel implementations of secret key generation,crypto functions and machine learning attacks are explored,respectively.For the low-power security applications in IoT,it is essential to understand how to best realize cryptographic circuitry using memristive circuitries,and to assess the implications of memristive crypto implementations on security and to develop novel computing paradigms that will enhance their security.This review article aims to help researchers to explore security solutions,to analyze new possible threats and to develop corresponding protections for the secure hardware systems based on low-cost memristive circuit designs.展开更多
基金supported by the Ministry of Sciences and Technology of China (863 programs, No 2006AA05Z115 and 2007AA05Z104)the National Natural Science Foundation of China (No. 20976121)
文摘Monolithic macroporous Pt/CeO2/Al2O3 catalysts were prepared using concentrated emulsions synthesis route, and the obtained samples were characterized with SEM, TG, TEM, XRD and TPR techniques. These monolithic catalysts were applied to water gas shift (WGS) reaction in reformed gases. The SEM and TEM results indicated that the monoliths possessed macroporosity, and that the platinum particles homogeneously dispersed on the supports with the particle size in the range of 1-2 nm. The reducibility of the catalysts was characterized by TPR method, and it was shown that the monolithic PtOx/CeO2/Al2O3 exhibited the similar reducibility property to that of the particle PtOx/CeO2 reported in literatures. The CO conversion over the monolithic catalysts is higher than that over micro-reactor catalysts for WGS reaction in the reformed gases conditions, indicating that the monolithic macroporous catalysts is a potential new route for miniaturization of WGS reactor.
文摘Based on previous work, a novel Frequency Selective Surface (FSS) consisting of two metallic layers is proposed. The first layer is inductive-designed to generate the band-pass performance, while the second layer is capacitive-designed so that the miniaturization characteristic can be further improved. As a result, compared with the traditional single-layer structure, the profile of the FSS proposed is relatively small with the cell’s dimension only 0.0814λ × 0.0814λ. Moreover, the structure’s stability corresponding to waves of different polarizations and incident angles are also testified, which ensures the practicability of the proposed structure.
基金the financial support provided by the National Research Foundation (NRF), Prime Minister’s Office, Singapore, under its Campus for Research Excellence and Technological Enterprise (CREATE) programpartially funded by the National University of Singapore under its Flagship Green Energy Program (GEP), Agency for Science, Technology and Research (A*STAR) under its Low Carbon Energy Research Funding Initiative (LCER-FI)Chongqing Science and Technology Research and Development Base Construction Project (cstc2013gjhz0029)
文摘Since the discovery of mesoporous silica in 1990s,there have been numerous mesoporous silica-based nanomaterials developed for catalytic applications,aiming at enhanced catalytic activity and stability.Recently,there have also been considerable interests in endowing them with hierarchical porosities to overcome the diffusional limitation for those with long unimodal channels.Present processes of making mesoporous silica largely rely on chemical sources which are relatively expensive and impose environmental concerns on their processes.In this regard,it is desirable to develop hierarchical silica supports from natural minerals.Herein,we present a series of work on surface reconstruction,modification,and functionalization to produce diatomite-based catalysts with original morphology and macro-meso-micro porosities and to test their suitability as catalyst supports for both liquid-and gas-phase reactions.Two wet-chemical routes were developed to introduce mesoporosity to both amorphous and crystalline diatomites.Importantly,we have used computational modeling to affirm that the diatomite morphology can improve catalytic performance based on fluid dynamics simulations.Thus,one could obtain this type of catalysts from numerous natural diatoms that have inherently intricate morphologies and shapes in micrometer scale.In principle,such catalytic nanocomposites acting as miniaturized industrial catalysts could be employed in microfluidic reactors for process intensification.
基金supported by the 11th Five-Year Plan under Grant No. 11001030203
文摘An uncommon fractal construction method is applied in the microwave element design. A novel fractal defected ground structure (DGS) based on micro electro-mechanical system (MEMS) is proposed. The size of this novel fractal DGS can achieve 86% size reduction compared with the conventional dumbbell type DGS. This novel fractal DGS is used in the miniaturization design of L-band microstrip antenna array. The simulation result shows that this novel fractal DGS can effectively reduce the mutual coupling between the antenna elements, so it is helpful to the miniaturization of microstrip array, namely the approximately same gain value can be achieved with the shorter distance between elements.
文摘Miniaturization and compact printed planar monopole antenna coplanar Waveguide CPW/microstrip feed line three half semi-circular (3HSC) with similar ground plane is presented, design, simulation, fabrication and tested experimentally for Ultra-Wideband (UWB) eommnnication application especially for WLAN and HIPERLAN/2 WLAN. The antenna design has a far from the traditional antennas such as a rectangular, circular, elliptical etc. Generating original planar antenna has been investigated to be an effect the combine geometry shapes of the radiation element part with the same geometry shapes of the slots in the ground plane. The simulation and measuring results have a good agreement, large bandwidth and radiation pattern behavior an omni-directional with stable gain has been obtained.
文摘The miniaturization and endurance of wearable devices have been the research direction for a long time.With the development of nanotechnology and the emergence of microelectronics products,people have explored many new strategies that may be applied to wearable devices.In this overview,we will summarize the recent research of wearable devices in these two directions,and summarize some available related technologies.
基金supported by the Natural Science Fund of China(51762023)the JiangXi Association for Science and Technology,the Jiangxi Provincial Department of Education,and the Training Program of Outstanding Young Scientists in Jiangxi Province(20171BCB23070).
文摘Magnetic,dielectric and DC conductive properties of Ni_(0.95-x)Zn_(x)Co_(0.05)Fe_(1.90)Mn_(0.02)O_(4)(with x=0-0.20 at an interval of 0.05)ferrite ceramics were studied,in order to develop magneto-dielectric materials with almost equal values of relative permeability and permittivity,for the miniaturization of HF(3-30 MHz)and VHF(30-90MHz and 100-300 MHz)antennas.The ferrite ceramics were prepared by using the conventional two-step sintering process.The real part of relative permeability is increased almost linearly with increasing concentration of Zn,while that of relative permittivity keeps nearly unchanged.It is found that promising magneto-dielectric materials,with close values of real permeability and permittivity over 30-90 MHz(VHF),can be obtained for the samples at Zn concentrations between x=0.05 and x=0.10.
基金financially supported by the National Natural Science Foundation of China(Nos.52172181 and22105017).
文摘Piezoelectric ceramics with high mechanical quality factor Q_(m) and large piezoelectric coefficient d_(33) are urgently required for advanced piezoelectric applications.However,obtaining both of these prop-erties simultaneously remains a difficult challenge due to their mutually restrictive relationship.Here 0.5Pb(Ni_(1/3)Nb_(2/3))O_(3)-0.5Pb(Zr_(0.3)Ti_(0.7))O_(3) piezoceramic with tetragonal(T)-rich MPB is designed as a matrix to construct the defect engineering by doping low-valent Mn ions.The strong coupling of defect dipole and T-rich phase can effectively hinder the rotation of P_(s),restrict domain wall motion and improve Q_(m).At the same time,the substituted Mn ions will introduce local random field,destroying the long-range or-dering of ferroelectric domain and reducing domain size.The miniaturized domain structure can increase poling efficiency and inhibit the reduction of d_(33).Guided by this strategy,Q_(m) has increased by more than 10 times and d_(33) has only decreased by about 25%.The optimized electromechanical performance with Q_(m)=822,d_(33)=502 pC/N,k_(p)=0.55 and tanδ=0.0069 can be obtained in the present study.
基金financially supported by the Sichuan Provincial Natural Science Foundation Project under Grant No.2023NSFSC0048.
文摘The miniaturized broadband detection module can be embedded into the microwave application system such as the front end of the transmitter to detect the power or other parameters in real time.It is highly prospective in military and scientific research.In this paper,a broadband power detection module operating at 26.5 GHz-40.0 GHz is designed by using low-barrier Schottky diode as the detector and a comparator for threshold output.This module can dynamically detect the power range between-10 dBm and 10 dBm with the detection accuracy of 0.1 dB.Further,the temperature compensation circuit is also applied to improve the measurement error.As a result,the resulted error low to±1 dB in the temperature range of -55℃ to +85℃ is achieved.The designed module is encapsulated by a Kovar alloy with a small volume of 9 mm×6 mm×3 mm.This endows the designed module the advantages of small size,easy integration,and low cost,and even it is applicable to high-reliability environments such as satellites.
基金supported by the National Natural Science Foundation of China,No. 81771228Shanghai Association of Science and Technology,Nos. 22WZ2501700 and 23WZ2504500 (all to LY)
文摘Bromodomain and plant homeodomain(PHD)finger containing protein 1(Brpf1)is an activator and scaffold protein of a multiunit complex that includes other components involving lysine acetyltransferase(KAT)6A/6B/7.Brpf1,KAT6A,and KAT6B mutations were identified as the causal genes of neurodevelopmental disorders leading to intellectual disability.Our previous work revealed strong and specific expression of Brpf1 in both the postnatal and adult forebrain,especially the hippocampus,which has essential roles in learning and memory.Here,we hypothesized that Brpf1 plays critical roles in the function of forebrain excitatory neurons,and that its deficiency leads to learning and memory deficits.To test this,we knocked out Brpf1 in forebrain excitatory neurons using CaMKIIa-Cre.We found that Brpf1 deficiency reduced the frequency of miniature excitatory postsynaptic currents and downregulated the expression of genes Pcdhgb1,Slc16a7,Robo3,and Rho,which are related to neural development,synapse function,and memory,thereby damaging spatial and fear memory in mice.These findings help explain the mechanisms of intellectual impairment in patients with BRPF1 mutation.
文摘Tunable Airy beams with controllable propagation trajectories have sparked interest in various fields,such as optical manipulation and laser fabrication.Existing research approaches encounter challenges related to insufficient compactness and integration feasibility,or they require enhanced tunability to enable real-time dynamic manipulation of the propagation trajectory.In this work,we present a novel method that utilizes a dual metasurface system to surpass these limitations,significantly enhancing the practical potential of the Airy beam.Our approach involves encoding a cubic phase profile and two off-axis Fresnel lens phase profiles across the two metasurfaces.The validity of the proposed strategy has been confirmed through simulation and experimental results.The proposed meta-device addresses the existing limitations and lays the foundation for broadening the applicability of Airy beams across diverse domains,encompassing light-sheet microscopy,laser fabrication,optical tweezers,etc.
基金financially supported by the Research Impact Fund (project no. R4015-21)Research Fellow Scheme (project no. RFS2122-4S03)+3 种基金Strategic Topics Grant (project no. STG1/E-401/23- N) from the Hong Kong Research Grants Council (RGC)the CUHK internal grantsthe support from Multi-Scale Medical Robotics Centre (MRC),InnoHK, at the Hong Kong Science Parkthe SIAT–CUHK Joint Laboratory of Robotics and Intelligent Systems
文摘Miniature devices comprising stimulus-responsive hydrogels with high environmental adaptability are now considered competitive candidates in the fields of biomedicine,precise sensors,and tunable optics.Reliable and advanced fabricationmethods are critical formaximizing the application capabilities ofminiature devices.Light-based three-dimensional(3D)printing technology offers the advantages of a wide range of applicable materials,high processing accuracy,and strong 3D fabrication capability,which is suitable for the development of miniature devices with various functions.This paper summarizes and highlights the recent advances in light-based 3D-printed miniaturized devices,with a focus on the latest breakthroughs in lightbased fabrication technologies,smart stimulus-responsive hydrogels,and tunable miniature devices for the fields of miniature cargo manipulation,targeted drug and cell delivery,active scaffolds,environmental sensing,and optical imaging.Finally,the challenges in the transition of tunable miniaturized devices from the laboratory to practical engineering applications are presented.Future opportunities that will promote the development of tunable microdevices are elaborated,contributing to their improved understanding of these miniature devices and further realizing their practical applications in various fields.
基金Special Scientific Research Project of Laboratory Animals,Grant/Award Number:SYDW[2018]14,SYDW[2020]01 and SYDW-KY[2021]03。
文摘Background:To explore potential biomarkers for early diagnosis of atherosclerosis(AS)and provide basic data for further research on AS,the characteristics of serum metabolomics during the progression of AS in mini-pigs were observed dynamically.Methods:An AS model in Bama miniature pigs was established by a high-cholesterol and high-fat diet.Fasting serum samples were collected monthly for metabolomics and serum lipid detection.At the end of the treatment period,pathological analysis of the abdominal aorta and coronary artery was performed to evaluate the lesions of AS,thereby distinguishing the susceptibility of mini-pigs to AS.The metabolomics was de-tected using a high-resolution untargeted metabolomic approach.Statistical analysis was used to identify metabolites associated with AS susceptibility.Results:Based on pathological analysis,mini-pigs were divided into two groups:a susceptible group(n=3)and a non-susceptible group(n=6).A total of 1318 metabo-lites were identified,with significant shifting of metabolic profiles over time in both groups.Dynamic monitoring analysis highlighted 57 metabolites that exhibited an ob-vious trend of differential changes between two groups with the advance of time.The KEGG(Kyoto Encyclopedia of Genes and Genomes)pathway enrichment analysis in-dicated significant disorders in cholesterol metabolism,primary bile acid metabolism,histidine metabolism,as well as taurine and hypotaurine metabolism.Conclusions:During the progression of AS in mini-pigs induced by high-cholesterol/high-fat diet,the alterations in serum metabolic profile exhibited a time-dependent pattern,accompanied by notable disturbances in lipid metabolism,cholesterol me-tabolism,and amino acid metabolism.These metabolites may become potential bio-markers for early diagnosis of AS.
基金supported by the National Natural Science Foundation of China(Grant Nos.22275092,52102107 and 52372084)the Fundamental Research Funds for the Central Universities(Grant No.30923010920)。
文摘Energetic Semiconductor bridge(ESCB)based on reactive multilayered films(RMFs)has a promising application in the miniature and intelligence of initiator and pyrotechnics device.Understanding the ignition enhancement mechanism of RMFs on semiconductor bridge(SCB)during the ignition process is crucial for the engineering and practical application of advanced initiator and pyrotechnics devices.In this study,a one-dimensional(1D)gas-solid two-phase flow ignition model was established to study the ignition process of ESCB to charge particles based on the reactivity of Al/MoO_(3) RMFs.In order to fully consider the coupled exothermic between the RMFs and the SCB plasma during the ignition process,the heat release of chemical reaction in RMFs was used as an internal heat source in this model.It is found that the exothermal reaction in RMFs improved the ignition performance of SCB.In the process of plasma rapid condensation with heat release,the product of RMFs enhanced the heat transfer process between the gas phase and the solid charge particle,which accelerated the expansion of hot plasma,and heated the solid charge particle as well as gas phase region with low temperature.In addition,it made up for pressure loss in the gas phase.During the plasma dissipation process,the exothermal chemical reaction in RMFs acted as the main heating source to heat the charge particle,making the surface temperature of the charge particle,gas pressure,and gas temperature rise continuously.This result may yield significant advantages in providing a universal ignition model for miniaturized ignition devices.
文摘Pig models are widely used in otological research. The establishment of common pig and miniature pig animal models has opened up new fields in otological research and is also an ideal large otological animal model. This article introduces the applications, current status, progress, advantages, and issues of using pigs as otologic animal models. It summarizes current research on pigs in the fields of hearing disorders, otitis, vertigo, cochlea, gene editing, and tissue engineering, among other otologic and audiological areas. These models are valuable for translating basic medical science into clinical applications. Based on this, platforms have been established for studying deafness and vertigo, cochlear implantation experiments, stem cell and gene therapy, and tissue engineering. These serve as ideal experimental models for the prevention and treatment of ear diseases, pointing toward new directions. This will bolster the promotion and application of pig models in the fields of tissue engineering and gene editing in the future.
基金The Bureau of Health of Jiangsu Province supported this study(H200939)the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD,2014-37)
文摘The putative causes of bruxism are multifactorial and there are no definite measures for bruxism management.The aim of this study was to evaluate the efficacy of biofeedback therapy on sleep bruxism,compared with occlusal splint.Twenty-four volunteers with sleep bruxism were divided into two groups:the GTB group that were treated with biofeedback therapy(n 512) and the GTO group that were treated with occlusal splint(n 512).A mini pressure sensor integrated with a monitoring circuit by use of a maxillary biofeedback splint was fabricated.To foster the relaxation of the masticatory muscles and the nervous system,the wireless device received signals from bruxism events and vibrations alerted the bruxer when the threshold was exceeded.Total episodes and average duration of bruxism events during8 hours of sleep were analyzed with the monitoring program(TRMY1.0).After 6 and 12 weeks,the episodes(P 50.001) and duration(P,0.05) in the GTB group declined dramatically.In contrast,there were no significant differences in the GTO group after the treatment(P.0.05).Furthermore,the episodes had significant differences between the GTB group and the GTO group after the same period of treatment(P 5 0.000).The results suggest that biofeedback therapy may be an effective and convenient measure for mild bruxers,when compared with occlusal splint therapy.The mini wireless biofeedback method may be of value for the diagnosis and management of bruxism in the future.
文摘Electrical sensing systems, such as those involving eutectic salt, are mostly used in connection to leakage from existing airborne high-temperature air-conducting pipelines. Such complex structured systems are susceptible to external interferences and, thus, cannot meet the increasingly strict monitoring needs of a complex air-conducting pipeline system of an aircraft. In view of this point, this paper studies an alternative sensor system based on a dense array fiber grating. To obtain a compact and light-weight airborne signal processing system, a field programmable gate array is used as the main control core that controls the output of the light source. The functions of pulse modulation, analog-to-digital conversion,data buffering and transmission are integrated into a single system, while the linear sensing monitoring is obtained by detecting the time-division and wavelength-division wavelength drift signals of the fiber Bragg grating array. Our experiments show that the spatial resolution of the linear sensing system approaches 5 cm, the temperature measurement accuracy reaches 2 ℃, the temperature measurement range is between 0–250 ℃, and the response time is within 4 s. Compared with the existing electrical monitoring systems, various monitoring indicators have been greatly improved and have broad application prospects.
基金Project supported by the National Natural Sciences Foundation of China (No. 50536040), the China Postdoctoral Science Foundation(No. 2005038280), and the Natural Sciences Foundation of ZhejiangProvince (No. Y104326), China
文摘A miniature thermoacoustic prime mover, consuming heat to radiate sound, may be considered as a potential way of heat management in microcircuits because of its simplicity and stability. A prototype with variable resonant tube length of 10 to 25 cm was built, and experiments were carried out to observe its performance, such as onset temperature, oscillation amplitude and operating frequency. The results with atmospheric air showed that proper structures and operating conditions can make the system start an oscillation at a temperature lower than 100 ℃, which proves the feasibility of potential usage in electronic units. The influences of stack position, heat input power or tube inclination on the oscillation amplitude, onset temperature and operating frequency are also presented.
文摘Due to the further intense human urbanization and industrialization,the environmental problems and climate changes became global issues that we have to face today.Like increasing environmental pollutants,ocean eutrophication,red-tide and acidification are causing irrevocably damages to the marine ecological environment.As an important part of marine ecosystem,macrobenthos plays an essential role in energy flow and substance circulation in the marine ecosystem.Therefore,the study of macrobenthic community structures and diversities were necessary,meanwhile the protection of macrobenthic diversity was also a tough problem.In recent years,many researches were mainly focus on Jiaozhou Bay of the Yellow Sea,the Yangtze Estuary,the coastal of Zhejiang and Fujian Provinces,while seldom on benthic organisms in the Bohai Sea.In this paper,the community structures and diversities of the common macrobenthos in the Bohai Sea were introduced and the macrobenthic response to environmental changes and environmental pollution caused by the construction of the Bohai Sea were also mentioned.The results showed that the large benthic fauna in th Bohai Sea was relatively simple compared to other China seas.There were about 400 species of large benthic organisms.The dominant species were low temperature and wide salt warm water.In the last five years,the annual average biomass was 23.82 g/m^2 and the annual average density was 1498 ind/m^2.The seasonal variation of average habitat density was usually summer autumn spring winter,and the average biomass was usually autumn spring summer winter.Original communities were destroyed and the dominant species appeared to be miniaturized caused by abuse of marine resources.Since the 21st century,the number of crustacean arthropods,bivalve molluscs,and echinoderms have decreased rapidly,but the number of polychaetes and small molluscs increased gradually.With the development of the comprehensive ecological management of the Bohai Sea,the ecological environment and habitat status in the studied area were remedied and improved.Afterwards,the trend of miniaturization was also suppressed.The results of this study presented some existed problems about marine ecological survey and provided some reasonable suggestions for the rational utilization and protection of marine resources.
基金supported by the DFG(German Research Foundation)Priority Program Nano Security,Project MemCrypto(Projektnummer 439827659/funding id DU 1896/2–1,PO 1220/15–1)the funding by the Fraunhofer Internal Programs under Grant No.Attract 600768。
文摘Emerging memristive devices offer enormous advantages for applications such as non-volatile memories and inmemory computing(IMC),but there is a rising interest in using memristive technologies for security applications in the era of internet of things(IoT).In this review article,for achieving secure hardware systems in IoT,lowpower design techniques based on emerging memristive technology for hardware security primitives/systems are presented.By reviewing the state-of-the-art in three highlighted memristive application areas,i.e.memristive non-volatile memory,memristive reconfigurable logic computing and memristive artificial intelligent computing,their application-level impacts on the novel implementations of secret key generation,crypto functions and machine learning attacks are explored,respectively.For the low-power security applications in IoT,it is essential to understand how to best realize cryptographic circuitry using memristive circuitries,and to assess the implications of memristive crypto implementations on security and to develop novel computing paradigms that will enhance their security.This review article aims to help researchers to explore security solutions,to analyze new possible threats and to develop corresponding protections for the secure hardware systems based on low-cost memristive circuit designs.