In this article,the legend for Fig.3 f&g was inadvertently mislabeled.The figure below shows the wrong one.The figure should have appeared as shown below.
Development of the telencephalon relies upon several signaling centers-localized cellular populations that supply secreted factors to pattern the cortical neuroepithelium.One such signaling center is the cortical hem,...Development of the telencephalon relies upon several signaling centers-localized cellular populations that supply secreted factors to pattern the cortical neuroepithelium.One such signaling center is the cortical hem,which arises during embryonic development at the telencephalic dorsal midline,adjacent to the choroid plexus and hippocampal primordium(Figure 1A).While the cortical hem has also been described in reptiles and birds,most of our knowledge about the developmental roles of the cortical hem is derived from the analysis in mice.The cortical hem produces several types of secreted molecules,including wingless-related integration site(Wnt)and bone morphogenetic(Bmp)proteins.The cortical hem is particularly important for the development of the hippocampus,which is involved in learning and memory,and the neocortex,which is the most complex brain region that mediates multiple types of behavior and higher cognitive functions(Mangale et al.,2008;Dal-Valle-Anton and Borrell,2022).展开更多
The neuromuscular junction(NMJ)is an essential synaptic structure composed of motor neurons,skeletal muscles,and glial cells that orchestrate the critical process of muscle contraction(Li et al.,2018).The typical NMJ ...The neuromuscular junction(NMJ)is an essential synaptic structure composed of motor neurons,skeletal muscles,and glial cells that orchestrate the critical process of muscle contraction(Li et al.,2018).The typical NMJ structure is classically described as having a“pretzel-like”shape in mice(Figure 1),whereas human NMJs have a smaller,fragmented structure throughout adulthood.Degenerated NMJs exhibit smaller or fragmented endplates,partial denervation,reduced numbers of synaptic vesicles,abnormal presynaptic mitochondria,and dysfunctional perisynaptic Schwann cells(Alhindi et al.,2022).展开更多
The metabolite lactate (L-lactate) can be generated and released by diverse brain cells,including neurons,astrocytes,and oligodendrocytes (Kann,2023;Rae et al.,2024).Lactate production usually requires the degradation...The metabolite lactate (L-lactate) can be generated and released by diverse brain cells,including neurons,astrocytes,and oligodendrocytes (Kann,2023;Rae et al.,2024).Lactate production usually requires the degradation of glucose (D-glucose)-and glycogen in astrocytes-to pyruvate by glycolysis and subsequent conversion of pyruvate to lactate by the enzyme lactate dehydrogenase(Figure 1A;Dienel,2019;Rae et al.,2024).展开更多
Manuscripts must generally be prepared according to the Publication Manual of the American Psychological Association.Formatting instructions for tables,figures,references,metrics,and abstracts appear in the APA Manual...Manuscripts must generally be prepared according to the Publication Manual of the American Psychological Association.Formatting instructions for tables,figures,references,metrics,and abstracts appear in the APA Manual.Guidance on APA Style is available on the APA Style website(http://www.apastyle.org/learn/tutorials/basics-tutorial.aspx).展开更多
Artificial intelligence(AI)can sometimes resolve difficulties that other advanced technologies and humans cannot.In medical diagnostics,AI has the advantage of processing figure recognition,especially for images with ...Artificial intelligence(AI)can sometimes resolve difficulties that other advanced technologies and humans cannot.In medical diagnostics,AI has the advantage of processing figure recognition,especially for images with similar characteristics that are difficult to distinguish with the naked eye.However,the mechanisms of this advanced technique should be well-addressed to elucidate clinical issues.In this letter,regarding an original study presented by Takayama et al,we suggest that the authors should effectively illustrate the mechanism and detailed procedure that artificial intelligence techniques processing the acquired images,including the recognition of non-obvious difference between the normal parts and pathological ones,which were impossible to be distinguished by naked eyes,such as the basic constitutional elements of pixels and grayscale,special molecules or even some metal ions which involved into the diseases occurrence.展开更多
The purpose of this paper is to present the results of investigations on quasi-one-dimensional organic crystals of tetrathiotetracene-tetracyanoquinodi- methane (TTT(TCNQ)<sub>2</sub>) from the prospective...The purpose of this paper is to present the results of investigations on quasi-one-dimensional organic crystals of tetrathiotetracene-tetracyanoquinodi- methane (TTT(TCNQ)<sub>2</sub>) from the prospective of thermoelectric applications. The calculations were performed after analytical expressions, obtained in the frame of a physical model, more detailed than the model presented earlier by authors. The main Hamiltonian of the model includes the electronic and phonon part, electron-phonon interactions and the impurity scattering term. In order to estimate the electric charge transport between the molecular chains, the physical model was upgraded to the so-called three-dimen- sional (3D) physical model. Numeric computations were performed to determine the electrical conductivity, Seebeck coefficient, thermal conductivity, thermoelectric power factor and thermoelectric figure-of-merit as a function on charge carrier concentrations, temperatures and impurity concentrations. A detailed analysis of charge-lattice interaction, consisting of the exploration of the Peierls structural transition in TCNQ molecular chains of TTT(TCNQ)<sub>2</sub> was performed. As result, the critical transition temperature was determined. The dispersion of renormalized phonons was examined in detail.展开更多
The fourth China International Consumer Products Expo,which was held from April 13 to 18,broke records for scale,as well as for numbers of new products,visitors and exhibited brands.A total of 4,019 brands from 71 cou...The fourth China International Consumer Products Expo,which was held from April 13 to 18,broke records for scale,as well as for numbers of new products,visitors and exhibited brands.A total of 4,019 brands from 71 countries and regions were presented at this year’s six-day expo in Haikou,the capital of south China’s Hainan Province,with those figures respectively increasing by 19 percent and 9 percent from last year,according to organizers.展开更多
This paper investigates the effects of pH on stability and thermal properties of copper oxide(CuO),graphene oxide(GO),and their hybrid nanofluid(HNF)at different mixing ratios.Initially,sol-gel and Hummer’s method wa...This paper investigates the effects of pH on stability and thermal properties of copper oxide(CuO),graphene oxide(GO),and their hybrid nanofluid(HNF)at different mixing ratios.Initially,sol-gel and Hummer’s method was employed for the synthesis of CuO and GO nanoparticles(NPs),and they are characterized with various techniques.The effects of two different surfactants were analyzed on nanofluid’s(NF’s)stability at different pH values.The properties like thermal conductivity(TC)and viscosity(VST)of NFs were measured at different volume concentration(0.1 vol%to 1.0 vol%)and temperature range of 30-60℃,respectively.The TC and VST of GO/CuO(50:50)HNF are higher than that of GO/CuO(20:80).The figure of merit(FOM)is determined for the studied HNFs.The correlations were presented to calculate the TC as well as VST of HNFs.Two modern novel machine learning-based ensemble approaches were employed for predictive model development for TC and VST of considered HNFs.The comparison of prognostic models with Taylor’s diagram revealed that Bayesian optimized support vector machine(BoASVM)was superior to Bayesian optimized boosted regression trees(BoA-BRT)for both TC and VST models.展开更多
Colorectal cancer(CRC)has become a major threat to human health.Recent years,improvements have been seen in the treatment of advanced CRC with immune checkpoint inhibitors(ICIs).Nonetheless,sensitivity to ICIs notably...Colorectal cancer(CRC)has become a major threat to human health.Recent years,improvements have been seen in the treatment of advanced CRC with immune checkpoint inhibitors(ICIs).Nonetheless,sensitivity to ICIs notably varies among patients,thus greatly limiting clinical applications of ICIs in CRC.Hence,the identification of biomarkers that can accurately distinguish between ICI-sensitive and drug-resistant patients is of utmost importance.Such biomarkers are essential for selecting appropriate treatment regimens and achieving precision therapy(Figure 1).The biomarkers discussed below provide insights into the advancements made in this field(Table 1).展开更多
A novel silicon carbide(SiC) trench metal–oxide–semiconductor field-effect transistor(MOSFET) with a dual shield gate(DSG) and optimized junction field-effect transistor(JFET) layer(ODSG-TMOS) is proposed. The combi...A novel silicon carbide(SiC) trench metal–oxide–semiconductor field-effect transistor(MOSFET) with a dual shield gate(DSG) and optimized junction field-effect transistor(JFET) layer(ODSG-TMOS) is proposed. The combination of the DSG and optimized JFET layer not only significantly improves the device’s dynamic performance but also greatly enhances the safe operating area(SOA). Numerical analysis is carried out with Silvaco TCAD to study the performance of the proposed structure. Simulation results show that comparing with the conventional asymmetric trench MOSFET(Con-ATMOS), the specific on-resistance(Ron,sp) is significantly reduced at almost the same avalanche breakdown voltage(BVav). Moreover, the DSG structure brings about much smaller reverse transfer capacitance(Crss) and input capacitance(Ciss), which helps to reduce the gate–drain charge(Qgd) and gate charge(Qg). Therefore, the high frequency figure of merit(HFFOM) of Ron,sp·Qgdand Ron,sp· Qgfor the proposed ODSG-TMOS are improved by 83.5% and 76.4%, respectively.The switching power loss of the proposed ODSG-TMOS is 77.0% lower than that of the Con-ATMOS. In addition, the SOA of the proposed device is also enhanced. The saturation drain current(Id,sat) at a gate voltage(Vgs) of 15 V for the ODSGTMOS is reduced by 17.2% owing to the JFET effect provided by the lower shield gate(SG) at a large drain voltage. With the reduced Id,sat, the short-circuit withstand time is improved by 87.5% compared with the Con-ATMOS. The large-current turn-off capability is also improved, which is important for the widely used inductive load applications.展开更多
Manuscripts must generally be prepared according to the Publication Manual of the American Psychological Association.Formatting instructions for tables,figures,references,metrics,and abstracts appear in the APA Manual...Manuscripts must generally be prepared according to the Publication Manual of the American Psychological Association.Formatting instructions for tables,figures,references,metrics,and abstracts appear in the APA Manual.Guidance on APA Style is available on the APA Style website(http://www.apastyle.org/learn/tutorials/basics-tutorial.aspx).展开更多
The surface flashover of epoxy resin(EP) composites is a pivotal problem in the field of highvoltage insulation.The regulation of the interface between the filler and matrix is an effective means to suppress flashover...The surface flashover of epoxy resin(EP) composites is a pivotal problem in the field of highvoltage insulation.The regulation of the interface between the filler and matrix is an effective means to suppress flashover.In this work,nano ZnO was fluorinated and grafted using lowtemperature plasma technology,and the fluorinated filler was doped into EP to study the DC surface flashover performance of the composite.The results show that plasma fluorination can effectively inhibit the agglomeration by grafting –CFxgroups onto the surface of nano-ZnO particles.The fluorine-containing groups at the interface provide higher charge binding traps and enhance the insulation strength at the interface.At the same time,the interface bond cooperation caused by plasma treatment also promoted the accelerating effect of nano ZnO on charge dissipation.The two effects synergistically improve the surface flashover performance of epoxy composites.When the concentration of fluorinated ZnO filler is 20%,the flashover voltage has the highest increase,which is 31.52% higher than that of pure EP.In addition,fluorinated ZnO can effectively reduce the dielectric constant and dielectric loss of epoxy composites.The interface interaction mechanism was further analyzed using molecular dynamics simulation and density functional theory simulation.展开更多
Manuscripts must generally be prepared according to the Publication Manual of the American Psychological Association.Formatting instructions for tables,figures,references,metrics,and abstracts appear in the APA Manual...Manuscripts must generally be prepared according to the Publication Manual of the American Psychological Association.Formatting instructions for tables,figures,references,metrics,and abstracts appear in the APA Manual.Guidance on APA Style is available on the APA Style website(http://www.apastyle.org/learn/tutorials/basics-tutorial.aspx).展开更多
Manuscripts must generally be prepared according to the Publication Manual of the American Psychological Association.Formatting instructions for tables,figures,references,metrics,and abstracts appear in the APA Manual...Manuscripts must generally be prepared according to the Publication Manual of the American Psychological Association.Formatting instructions for tables,figures,references,metrics,and abstracts appear in the APA Manual.Guidance on APA Style is available on the APA Style website(http://www.apastyle.org/learn/tutorials/basics-tutorial.aspx).展开更多
Surface coating technology is an effective way to solve the interface insulation problem of DC GIS/GIL basin insulators, but the performance of the coating will change greatly, and the insulation strength will be comp...Surface coating technology is an effective way to solve the interface insulation problem of DC GIS/GIL basin insulators, but the performance of the coating will change greatly, and the insulation strength will be completely lost, after long-term use in the extreme conditions of corona erosion. In this research, the multi-needle-plate electrode platform was constructed to explore the long-term use performance of Si C-doped nanocomposite exposed to corona discharge in SF6gas. Samples with a high Si C content have advantages in maintaining physical and chemical properties such as elemental composition, erosion depth, surface roughness and mass loss. The nanocomposite doped with 6 wt.% Si C has prominent surface insulation strength after long term exposure to corona, and the others are close to losing, or have completely lost,their insulating properties. Furthermore, the degradation mechanism of physicochemical properties of composite exposed to corona discharge was investigated with the proposed Reax FF MD model of energetic particles from SF6decomposition bombarding the epoxy surface. The reaction process of SF particles and F particles with the cross-linked epoxy resin, and the Si C nanoparticles providing shelter to the surrounding polymer and mitigating their suffering direct bombardment, have been established. The damage propagation depth, mass loss and surface roughness change of nanocomposite material bombarded by SF6decomposition products is reproduced in this simulation. Finally, the deterioration mechanism of insulation properties for the Si C-doped composite was elucidated with DFT analysis. The band gap of the molecule containing S drops directly from the initial 7.785 e V to 1.875 e V, which causes the deterioration of surface electric properties.展开更多
This work deals with the experimental study of a surface dielectric-barrier discharge,as a part of the ongoing interest in the control of plasma induced electro-fluid dynamic effects(e.g.plasma actuators).The discharg...This work deals with the experimental study of a surface dielectric-barrier discharge,as a part of the ongoing interest in the control of plasma induced electro-fluid dynamic effects(e.g.plasma actuators).The discharge is generated using a plasma reactor consisting of a fused silica plate which is sandwiched between two printed circuit boards where the electrodes are developed.The reactor is driven by narrow high voltage square pulses of asymmetric rising(25 ns)and falling(2.5μs)parts,while the discharge evolution is considered in a temporarily and spatially resolved manner over these pulses.That is,conventional electrical and optical emission analyzes are combined with high resolution optical emission spectroscopy and ns-resolved imaging,unveiling main characteristics of the discharge with a special focus on its propagation along the dielectric-barrier surface.The voltage rising part leads to cathode-directed ionization waves,which propagate with a speed up to 105m s~(-1).The voltage falling part leads to cathode sheath formation on the driven electrode.Τhe polarization of the dielectric barrier appears critical for the discharge dynamics.展开更多
A radio-frequency(RF) inductively coupled negative hydrogen ion source(NHIS) has been adopted in the China Fusion Engineering Test Reactor(CFETR) to generate negative hydrogen ions.By incorporating the level-lumping m...A radio-frequency(RF) inductively coupled negative hydrogen ion source(NHIS) has been adopted in the China Fusion Engineering Test Reactor(CFETR) to generate negative hydrogen ions.By incorporating the level-lumping method into a three-dimensional fluid model,the volume production and transportation of H^(-) in the NHIS,which consists of a cylindrical driver region and a rectangular expansion chamber,are investigated self-consistently at a large input power(40 k W) and different pressures(0.3–2.0 Pa).The results indicate that with the increase of pressure,the H^(-) density at the bottom of the expansion region first increases and then decreases.In addition,the effect of the magnetic filter is examined.It is noteworthy that a significant increase in the H^(-) density is observed when the magnetic filter is introduced.As the permanent magnets move towards the driver region,the H^(-) density decreases monotonically and the asymmetry is enhanced.This study contributes to the understanding of H-distribution under various conditions and facilitates the optimization of volume production of negative hydrogen ions in the NHIS.展开更多
A comprehensive behavioral investigation of gain and noise figure (NF) at different erbium doped fiber amplifier (EDFA) configurations is proposed. Configurations such as single pass (SP), single pass with filt...A comprehensive behavioral investigation of gain and noise figure (NF) at different erbium doped fiber amplifier (EDFA) configurations is proposed. Configurations such as single pass (SP), single pass with filter (SPF), double pass (DP) and double pass with filter (DPF) are designed, investigated and compared. A continuous increasing of gain value is recorded by changing the configuration from SP to SPF to DP then to DPF. The NF value shows different behaviors at different configurations.展开更多
The magnetic property of soft magnetic metals and alloys depends strongly on the crystallo-graphic orientation. In automated equipment for orientation research, the intensity for drawing up the pole figure is measured...The magnetic property of soft magnetic metals and alloys depends strongly on the crystallo-graphic orientation. In automated equipment for orientation research, the intensity for drawing up the pole figure is measured in detail. The present research shows that the accurate pole figure can be drawn up without measuring concretely the intensity. For directional Si steel sheet the measuring step may be 4~5 degrees. In this paper the experimental equation for defo-cusing correction was derived from the experimental data in different specimens with random orientation.展开更多
基金Supported by the National Natural Science Foundation of China (Nos. 42061134020, 32070380)the Natural Science Foundation of Shandong Province (No. ZR2019ZD17)
文摘In this article,the legend for Fig.3 f&g was inadvertently mislabeled.The figure below shows the wrong one.The figure should have appeared as shown below.
基金supported by R01 NS093009 grant from NIH(to VVC).
文摘Development of the telencephalon relies upon several signaling centers-localized cellular populations that supply secreted factors to pattern the cortical neuroepithelium.One such signaling center is the cortical hem,which arises during embryonic development at the telencephalic dorsal midline,adjacent to the choroid plexus and hippocampal primordium(Figure 1A).While the cortical hem has also been described in reptiles and birds,most of our knowledge about the developmental roles of the cortical hem is derived from the analysis in mice.The cortical hem produces several types of secreted molecules,including wingless-related integration site(Wnt)and bone morphogenetic(Bmp)proteins.The cortical hem is particularly important for the development of the hippocampus,which is involved in learning and memory,and the neocortex,which is the most complex brain region that mediates multiple types of behavior and higher cognitive functions(Mangale et al.,2008;Dal-Valle-Anton and Borrell,2022).
基金funded by the Japan Society for the Promotion of Science,JSPS,23K07290(to MF).
文摘The neuromuscular junction(NMJ)is an essential synaptic structure composed of motor neurons,skeletal muscles,and glial cells that orchestrate the critical process of muscle contraction(Li et al.,2018).The typical NMJ structure is classically described as having a“pretzel-like”shape in mice(Figure 1),whereas human NMJs have a smaller,fragmented structure throughout adulthood.Degenerated NMJs exhibit smaller or fragmented endplates,partial denervation,reduced numbers of synaptic vesicles,abnormal presynaptic mitochondria,and dysfunctional perisynaptic Schwann cells(Alhindi et al.,2022).
文摘The metabolite lactate (L-lactate) can be generated and released by diverse brain cells,including neurons,astrocytes,and oligodendrocytes (Kann,2023;Rae et al.,2024).Lactate production usually requires the degradation of glucose (D-glucose)-and glycogen in astrocytes-to pyruvate by glycolysis and subsequent conversion of pyruvate to lactate by the enzyme lactate dehydrogenase(Figure 1A;Dienel,2019;Rae et al.,2024).
文摘Manuscripts must generally be prepared according to the Publication Manual of the American Psychological Association.Formatting instructions for tables,figures,references,metrics,and abstracts appear in the APA Manual.Guidance on APA Style is available on the APA Style website(http://www.apastyle.org/learn/tutorials/basics-tutorial.aspx).
基金Supported by the Dean Responsible Project of Gansu Medical College,No.GY-2023FZZ01University Teachers Innovation Fund Project of Gansu Province,No.2023A-182and Key Research Project of Pingliang Science and Technology,No.PL-STK-2021A-004.
文摘Artificial intelligence(AI)can sometimes resolve difficulties that other advanced technologies and humans cannot.In medical diagnostics,AI has the advantage of processing figure recognition,especially for images with similar characteristics that are difficult to distinguish with the naked eye.However,the mechanisms of this advanced technique should be well-addressed to elucidate clinical issues.In this letter,regarding an original study presented by Takayama et al,we suggest that the authors should effectively illustrate the mechanism and detailed procedure that artificial intelligence techniques processing the acquired images,including the recognition of non-obvious difference between the normal parts and pathological ones,which were impossible to be distinguished by naked eyes,such as the basic constitutional elements of pixels and grayscale,special molecules or even some metal ions which involved into the diseases occurrence.
文摘The purpose of this paper is to present the results of investigations on quasi-one-dimensional organic crystals of tetrathiotetracene-tetracyanoquinodi- methane (TTT(TCNQ)<sub>2</sub>) from the prospective of thermoelectric applications. The calculations were performed after analytical expressions, obtained in the frame of a physical model, more detailed than the model presented earlier by authors. The main Hamiltonian of the model includes the electronic and phonon part, electron-phonon interactions and the impurity scattering term. In order to estimate the electric charge transport between the molecular chains, the physical model was upgraded to the so-called three-dimen- sional (3D) physical model. Numeric computations were performed to determine the electrical conductivity, Seebeck coefficient, thermal conductivity, thermoelectric power factor and thermoelectric figure-of-merit as a function on charge carrier concentrations, temperatures and impurity concentrations. A detailed analysis of charge-lattice interaction, consisting of the exploration of the Peierls structural transition in TCNQ molecular chains of TTT(TCNQ)<sub>2</sub> was performed. As result, the critical transition temperature was determined. The dispersion of renormalized phonons was examined in detail.
文摘The fourth China International Consumer Products Expo,which was held from April 13 to 18,broke records for scale,as well as for numbers of new products,visitors and exhibited brands.A total of 4,019 brands from 71 countries and regions were presented at this year’s six-day expo in Haikou,the capital of south China’s Hainan Province,with those figures respectively increasing by 19 percent and 9 percent from last year,according to organizers.
文摘This paper investigates the effects of pH on stability and thermal properties of copper oxide(CuO),graphene oxide(GO),and their hybrid nanofluid(HNF)at different mixing ratios.Initially,sol-gel and Hummer’s method was employed for the synthesis of CuO and GO nanoparticles(NPs),and they are characterized with various techniques.The effects of two different surfactants were analyzed on nanofluid’s(NF’s)stability at different pH values.The properties like thermal conductivity(TC)and viscosity(VST)of NFs were measured at different volume concentration(0.1 vol%to 1.0 vol%)and temperature range of 30-60℃,respectively.The TC and VST of GO/CuO(50:50)HNF are higher than that of GO/CuO(20:80).The figure of merit(FOM)is determined for the studied HNFs.The correlations were presented to calculate the TC as well as VST of HNFs.Two modern novel machine learning-based ensemble approaches were employed for predictive model development for TC and VST of considered HNFs.The comparison of prognostic models with Taylor’s diagram revealed that Bayesian optimized support vector machine(BoASVM)was superior to Bayesian optimized boosted regression trees(BoA-BRT)for both TC and VST models.
基金supported by the National Natural Science Foundation of China(Grant No.82272841).
文摘Colorectal cancer(CRC)has become a major threat to human health.Recent years,improvements have been seen in the treatment of advanced CRC with immune checkpoint inhibitors(ICIs).Nonetheless,sensitivity to ICIs notably varies among patients,thus greatly limiting clinical applications of ICIs in CRC.Hence,the identification of biomarkers that can accurately distinguish between ICI-sensitive and drug-resistant patients is of utmost importance.Such biomarkers are essential for selecting appropriate treatment regimens and achieving precision therapy(Figure 1).The biomarkers discussed below provide insights into the advancements made in this field(Table 1).
基金Project supported by the China Postdoctoral Science Foundation (Grant No. 2020M682607)。
文摘A novel silicon carbide(SiC) trench metal–oxide–semiconductor field-effect transistor(MOSFET) with a dual shield gate(DSG) and optimized junction field-effect transistor(JFET) layer(ODSG-TMOS) is proposed. The combination of the DSG and optimized JFET layer not only significantly improves the device’s dynamic performance but also greatly enhances the safe operating area(SOA). Numerical analysis is carried out with Silvaco TCAD to study the performance of the proposed structure. Simulation results show that comparing with the conventional asymmetric trench MOSFET(Con-ATMOS), the specific on-resistance(Ron,sp) is significantly reduced at almost the same avalanche breakdown voltage(BVav). Moreover, the DSG structure brings about much smaller reverse transfer capacitance(Crss) and input capacitance(Ciss), which helps to reduce the gate–drain charge(Qgd) and gate charge(Qg). Therefore, the high frequency figure of merit(HFFOM) of Ron,sp·Qgdand Ron,sp· Qgfor the proposed ODSG-TMOS are improved by 83.5% and 76.4%, respectively.The switching power loss of the proposed ODSG-TMOS is 77.0% lower than that of the Con-ATMOS. In addition, the SOA of the proposed device is also enhanced. The saturation drain current(Id,sat) at a gate voltage(Vgs) of 15 V for the ODSGTMOS is reduced by 17.2% owing to the JFET effect provided by the lower shield gate(SG) at a large drain voltage. With the reduced Id,sat, the short-circuit withstand time is improved by 87.5% compared with the Con-ATMOS. The large-current turn-off capability is also improved, which is important for the widely used inductive load applications.
文摘Manuscripts must generally be prepared according to the Publication Manual of the American Psychological Association.Formatting instructions for tables,figures,references,metrics,and abstracts appear in the APA Manual.Guidance on APA Style is available on the APA Style website(http://www.apastyle.org/learn/tutorials/basics-tutorial.aspx).
基金supported by Beijing Natural Science Foundation (No. 3222057)National Natural Science Foundation of China (Nos. 52277147 and 52007065)。
文摘The surface flashover of epoxy resin(EP) composites is a pivotal problem in the field of highvoltage insulation.The regulation of the interface between the filler and matrix is an effective means to suppress flashover.In this work,nano ZnO was fluorinated and grafted using lowtemperature plasma technology,and the fluorinated filler was doped into EP to study the DC surface flashover performance of the composite.The results show that plasma fluorination can effectively inhibit the agglomeration by grafting –CFxgroups onto the surface of nano-ZnO particles.The fluorine-containing groups at the interface provide higher charge binding traps and enhance the insulation strength at the interface.At the same time,the interface bond cooperation caused by plasma treatment also promoted the accelerating effect of nano ZnO on charge dissipation.The two effects synergistically improve the surface flashover performance of epoxy composites.When the concentration of fluorinated ZnO filler is 20%,the flashover voltage has the highest increase,which is 31.52% higher than that of pure EP.In addition,fluorinated ZnO can effectively reduce the dielectric constant and dielectric loss of epoxy composites.The interface interaction mechanism was further analyzed using molecular dynamics simulation and density functional theory simulation.
文摘Manuscripts must generally be prepared according to the Publication Manual of the American Psychological Association.Formatting instructions for tables,figures,references,metrics,and abstracts appear in the APA Manual.Guidance on APA Style is available on the APA Style website(http://www.apastyle.org/learn/tutorials/basics-tutorial.aspx).
文摘Manuscripts must generally be prepared according to the Publication Manual of the American Psychological Association.Formatting instructions for tables,figures,references,metrics,and abstracts appear in the APA Manual.Guidance on APA Style is available on the APA Style website(http://www.apastyle.org/learn/tutorials/basics-tutorial.aspx).
基金supported by National Natural Science Foundation of China(Nos.51737005,51929701,52177147 and 52127812)。
文摘Surface coating technology is an effective way to solve the interface insulation problem of DC GIS/GIL basin insulators, but the performance of the coating will change greatly, and the insulation strength will be completely lost, after long-term use in the extreme conditions of corona erosion. In this research, the multi-needle-plate electrode platform was constructed to explore the long-term use performance of Si C-doped nanocomposite exposed to corona discharge in SF6gas. Samples with a high Si C content have advantages in maintaining physical and chemical properties such as elemental composition, erosion depth, surface roughness and mass loss. The nanocomposite doped with 6 wt.% Si C has prominent surface insulation strength after long term exposure to corona, and the others are close to losing, or have completely lost,their insulating properties. Furthermore, the degradation mechanism of physicochemical properties of composite exposed to corona discharge was investigated with the proposed Reax FF MD model of energetic particles from SF6decomposition bombarding the epoxy surface. The reaction process of SF particles and F particles with the cross-linked epoxy resin, and the Si C nanoparticles providing shelter to the surrounding polymer and mitigating their suffering direct bombardment, have been established. The damage propagation depth, mass loss and surface roughness change of nanocomposite material bombarded by SF6decomposition products is reproduced in this simulation. Finally, the deterioration mechanism of insulation properties for the Si C-doped composite was elucidated with DFT analysis. The band gap of the molecule containing S drops directly from the initial 7.785 e V to 1.875 e V, which causes the deterioration of surface electric properties.
文摘This work deals with the experimental study of a surface dielectric-barrier discharge,as a part of the ongoing interest in the control of plasma induced electro-fluid dynamic effects(e.g.plasma actuators).The discharge is generated using a plasma reactor consisting of a fused silica plate which is sandwiched between two printed circuit boards where the electrodes are developed.The reactor is driven by narrow high voltage square pulses of asymmetric rising(25 ns)and falling(2.5μs)parts,while the discharge evolution is considered in a temporarily and spatially resolved manner over these pulses.That is,conventional electrical and optical emission analyzes are combined with high resolution optical emission spectroscopy and ns-resolved imaging,unveiling main characteristics of the discharge with a special focus on its propagation along the dielectric-barrier surface.The voltage rising part leads to cathode-directed ionization waves,which propagate with a speed up to 105m s~(-1).The voltage falling part leads to cathode sheath formation on the driven electrode.Τhe polarization of the dielectric barrier appears critical for the discharge dynamics.
基金supported by the National Key R&D Program of China (No. 2017YFE0300106)National Natural Science Foundation of China (Nos. 11935005 and 12075049)the Fundamental Research Funds for the Central Universities(Nos. DUT21TD104 and DUT21LAB110)。
文摘A radio-frequency(RF) inductively coupled negative hydrogen ion source(NHIS) has been adopted in the China Fusion Engineering Test Reactor(CFETR) to generate negative hydrogen ions.By incorporating the level-lumping method into a three-dimensional fluid model,the volume production and transportation of H^(-) in the NHIS,which consists of a cylindrical driver region and a rectangular expansion chamber,are investigated self-consistently at a large input power(40 k W) and different pressures(0.3–2.0 Pa).The results indicate that with the increase of pressure,the H^(-) density at the bottom of the expansion region first increases and then decreases.In addition,the effect of the magnetic filter is examined.It is noteworthy that a significant increase in the H^(-) density is observed when the magnetic filter is introduced.As the permanent magnets move towards the driver region,the H^(-) density decreases monotonically and the asymmetry is enhanced.This study contributes to the understanding of H-distribution under various conditions and facilitates the optimization of volume production of negative hydrogen ions in the NHIS.
基金MMU and KFUPM/HBCC for their support in providing the various facilities utilized in the presentation of this paper
文摘A comprehensive behavioral investigation of gain and noise figure (NF) at different erbium doped fiber amplifier (EDFA) configurations is proposed. Configurations such as single pass (SP), single pass with filter (SPF), double pass (DP) and double pass with filter (DPF) are designed, investigated and compared. A continuous increasing of gain value is recorded by changing the configuration from SP to SPF to DP then to DPF. The NF value shows different behaviors at different configurations.
文摘The magnetic property of soft magnetic metals and alloys depends strongly on the crystallo-graphic orientation. In automated equipment for orientation research, the intensity for drawing up the pole figure is measured in detail. The present research shows that the accurate pole figure can be drawn up without measuring concretely the intensity. For directional Si steel sheet the measuring step may be 4~5 degrees. In this paper the experimental equation for defo-cusing correction was derived from the experimental data in different specimens with random orientation.