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A novel microwave absorption and dielectric spectrum detection technology in photoelectron dynamic study for solar cells
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作者 LI Xiaowei SUN Shuxu LAI Weidong ZHANG Rongxiang DAI Xiuhong JIANG Xiaoli 《Rare Metals》 SCIE EI CAS CSCD 2006年第z1期153-157,共5页
The photoelectron property is directly related to the light-energy conversion efficiency of solar cells. In this paper, the photoelectron dynamic of semiconductor was analyzed. The diffusion of electrons has influence... The photoelectron property is directly related to the light-energy conversion efficiency of solar cells. In this paper, the photoelectron dynamic of semiconductor was analyzed. The diffusion of electrons has influence on the dielectric function of the solar cell material. And the amplitude variance of the imaginary and real part of the dielectric function is in direct proportion to the dynamic process of free and shallow-trapped electrons. Based on the untouched detection technique, the method is present to detect the amplitude change of the microwave signal which is passing through the material whose dielectric function changes after exposure. A 35 GHz oscillator was used as a microwave source. The absorption and dispersion microwave signals, which contain the dynamic information of free and shallow-trapped electron signal, are split respectively with phase-sensitive instrument. The photoelectron character of n-type Si(100) thin film was investigated by the novel equipment, and the lifetime of different kinds of electrons with the resolution of 1 ns was obtained. The equipment can be directly used in the study of the optoelectronic conversion mechanism of solar cells. 展开更多
关键词 dye sensitization solar cells microwave absorption dielectric spectrum
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Spectrum FSY Microwave可抵御恶劣环境的发射塔用放大器
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《电子产品世界》 2004年第07B期27-27,共1页
关键词 spectrum FSY microwave公司 天线塔架 放大器 防雷保护 性能
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Crystal microstructure, infrared absorption, and microwave electromagnetic properties of (La_(1-x)Dy_x)_(2/3)Sr_(1/3)MnO_3 被引量:2
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作者 LIU Jian YUN Guohong SU Meiling 《Rare Metals》 SCIE EI CAS CSCD 2009年第5期494-499,共6页
The manganite perovskite polycrystal samples of (La1-xDyx)2/3Sr1/3MnO3 (x = 0, 0.1, 0.2, 0.35, and 0.5) doped with Dy were prepared by solid state reaction in atmosphere to measure their X-ray diffraction (XRD) ... The manganite perovskite polycrystal samples of (La1-xDyx)2/3Sr1/3MnO3 (x = 0, 0.1, 0.2, 0.35, and 0.5) doped with Dy were prepared by solid state reaction in atmosphere to measure their X-ray diffraction (XRD) patterns, scanning electric microscope (SEM) images, infrared absorption spectra, and microwave electromagnetic properties. The displacement of the XRD peaks of the samples was found, and the 2θ increases from 0.05o to 0.5o. The grains of undoped La2/3Sr1/3MnO3 not only have the greatest size, but also the most regular shape. The size of the grains decreases as the Dy doping content increases from 0 to 0.5. The infrared absorption spectra of all samples were measured at room temperature. An absorption peak corresponding to the stretching vibration mode of Mn-O bonds appears within the range of 591-629 cm-1. The absorption peak shifts from a higher frequency to a lower one with the decrease of the average ionic radius of A-site. The frequency de- pendence of microwave-absorbing properties, imaginary components of the complex magnetic permeability μ" and dielectric permeability ε" for all samples was measured at room temperature from 8 to 13 GHz. The results show that the loss of microwave absorption can be attrib- uted to both the magnetic and electric losses. The increase of Dy content not only enhances the microwave absorption but also causes the displacement of the absorption peaks. 展开更多
关键词 MANGANITE crystal microstructure infrared absorption spectrum microwave electromagnetic property DOPING rare earth
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Inspections of Mobile Phone Microwaves Effects on Proteins Secondary Structure by Means of Fourier Transform Infrared Spectroscopy 被引量:2
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作者 Emanuele Calabrò Salvatore Magazù 《Journal of Electromagnetic Analysis and Applications》 2010年第11期607-617,共11页
In this study the effects of microwaves on the secondary structure of three typical proteins have been investigated. A set of samples of lysozyme, bovine serum albumin and myoglobin in D2O solutions were exposed for 8... In this study the effects of microwaves on the secondary structure of three typical proteins have been investigated. A set of samples of lysozyme, bovine serum albumin and myoglobin in D2O solutions were exposed for 8 hours to mobile phone microwaves at 900 MHz at a magnetic field intensity around 16 mA/m. The relative effects on the secondary structure of the proteins were studied by means of Fourier Transform Infrared Spectroscopy. An increase of the amide I band intensity in the secondary structure of the proteins was observed after the microwaves exposure. Furthermore, a weak shift of the amide I mode of bovine serum albumin and a heavier shift of the amide I of myoglobin occurred after the exposure. In addition, a clear increasing of the β-sheet components with respect to the α-helix content was observed in the spectra of bovine serum albumin and myoglobin after the exposure, suggesting the hypothesis of the formation of aggregates. 展开更多
关键词 Mobile PHONE microwaves PROTEIN Infrared spectrum SECONDARY Structure AMIDE I
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Time-resolved Microwave Conductivity Studies on the Chemical Treatment of the Nanocrystalline Porous TiO2 Films
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作者 YuanLIN XuRuiXIAO +3 位作者 WeiYingLI XuePingLI WeiBoWANG imgVongCHENG 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第7期734-736,共3页
Effect of Ti(iso-C3H7O)4 treatment on the photoinduced charge carrier kinetics of nanocrystalline porous TiO2 films is studied by time-resolved microwave conductivity measurements. Analysis of the transient photocond... Effect of Ti(iso-C3H7O)4 treatment on the photoinduced charge carrier kinetics of nanocrystalline porous TiO2 films is studied by time-resolved microwave conductivity measurements. Analysis of the transient photoconductivity decays indicates that Ti(iso-C3H7O)4 treatment leads to an increased concentration of photogenerated charge carriers and a fast interfacial transfer rate of holes via the surface modification of the freshly growing TiO2 nanocrystallites. 展开更多
关键词 Nanocrystalline porous TiO2 films chemical treatment transient photoconductivity charge carrier kinetics time-resolved microwave conductivity.
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Recent Advances in Short-Range Microwave Imaging in Europe
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作者 Matteo Pastorino (Department of Biophysical and Electronic Engineering, University of Genova, Italy) 《Advances in Manufacturing》 SCIE CAS 1998年第1期4-17,共14页
This paper reports the content of a lecture presented at the 1995 International Conference and Exhibition on Electronic Measurement and Instrumentation, held in Shanghai, China in 1995. The paper presents(thanks to th... This paper reports the content of a lecture presented at the 1995 International Conference and Exhibition on Electronic Measurement and Instrumentation, held in Shanghai, China in 1995. The paper presents(thanks to the courtesy of several scientists) some of the most significant results recently obtained in the field of short range microwave imaging. The overview concerns the research activity carried out in Europe and is focused on microwave imaging for non destructive testing, civil engineering, and scientific and medical applications. This type of imaging is characterized by a relatively short distance between the object to be detected and the probes. 展开更多
关键词 microwave imaging inverse scattering spectrum domain method space domain method
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Flexible regulation engineering of titanium nitride nanofibrous membranes for efficient electromagnetic microwave absorption in wide temperature spectrum 被引量:6
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作者 Cuiping Li Lu Zhang +5 位作者 Shuai Zhang Qiqi Yu Dan Li Lei Zhang Chunhong Gong Jingwei Zhang 《Nano Research》 SCIE EI CSCD 2024年第3期1666-1675,共10页
Simultaneous development of well impedance matching and strong loss capability has become a mainstream method for achieving outstanding electromagnetic microwave absorption(EMWA)performances over wide temperature rang... Simultaneous development of well impedance matching and strong loss capability has become a mainstream method for achieving outstanding electromagnetic microwave absorption(EMWA)performances over wide temperature range.However,it is difficult to pursue both due to the mutual restraint of relationship between impedance matching and loss capability about temperature.Here,we propose a flexible regulation engineering of titanium nitride(TiN)nanofibrous membranes(NMs,TNMs),which could be distributed uniformly in the polydimethylsiloxane(PDMS)matrix and contributed to the formation of abundant local conductive networks,generating the local conductive loss and enhancing the loss ability of EMWs.Moreover,when the TNMs are used as functional units and dispersed in the matrix,the corresponding composites exhibit an outstanding anti-reflection effect on microwaves.As hoped,under the precondition of good impedance matching,local conductive loss and polarization loss together improve the loss capacity at room temperature,and polarization loss can compensate the local conductive loss to acquire effective dielectric response at elevated temperature.Benefiting from the reasonably synergistic loss ability caused by flexible regulation engineering,the corresponding composites exhibit the perfect EMWA performances in a wide temperature range from 298 to 573 K.This work not only elaborates the ponderable insights of independent membrane in the composition-structure-function connection,but also provides a feasible tactic for resolving coexistence of well impedance matching and strong loss capability issues in wide temperature spectrum. 展开更多
关键词 flexible titanium nitride nanofibrous membranes local conductive loss dielectric loss electromagnetic microwave absorption wide temperature spectrum
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Recent progress of parameter-adjustable high-power photonic microwave generation based on wide-bandgap photoconductive semiconductors
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作者 荀涛 牛昕玥 +7 位作者 王朗宁 张斌 姚金妹 易木俣 杨汉武 侯静 刘金亮 张建徳 《Chinese Optics Letters》 SCIE EI CAS CSCD 2024年第1期113-122,共10页
Radio frequency/microwave-directed energy sources using wide bandgap SiC photoconductive semiconductors have attracted much attention due to their unique advantages of high-power output and multi-parameter adjustable ... Radio frequency/microwave-directed energy sources using wide bandgap SiC photoconductive semiconductors have attracted much attention due to their unique advantages of high-power output and multi-parameter adjustable ability.Over the past several years,benefitting from the sustainable innovations in laser technology and the significant progress in materials technology,megawatt-class output power electrical pulses with a flexible frequency in the P and L microwave wavebands have been achieved by photoconductive semiconductor devices.Here,we mainly summarize and review the recent progress of the high-power photonic microwave generation based on the SiC photoconductive semiconductor devices in the linear modulation mode,including the mechanism,system architecture,critical technology,and experimental demonstration of the proposed high-power photonic microwave sources.The outlooks and challenges for the future of multi-channel power synthesis development of higher power photonic microwave using wide bandgap photoconductors are also discussed. 展开更多
关键词 high-power photonic microwave wide bandgap photoconductive semiconductor devices linear modulation multi-parameter adjustable microwave generation multi-channel power synthesis
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Retrieving capillary-gravity wave spectrum from polarimetric microwave radiation of ocean surface
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作者 YIN XiaoBin WANG ZhenZhan LIU YuGuang 《Science China Earth Sciences》 SCIE EI CAS 2010年第6期901-910,共10页
A new simple two-scale model on the polarimetric microwave emission of ocean surface is derived at first, which can be ex-pressed as an integral of weighting functions (M0 and M2) and ocean surface curvature spectrum ... A new simple two-scale model on the polarimetric microwave emission of ocean surface is derived at first, which can be ex-pressed as an integral of weighting functions (M0 and M2) and ocean surface curvature spectrum coefficients (C0 and C2). This provides a simple way to investigate the effect of curvature spectrum on ocean emission. It is found that ocean waves with wavelengths both comparable to and much greater than the electromagnetic wavelength can contribute to the harmonics of ocean surface microwave emission, depending on the magnitude of the ocean surface spectrum in these length scales. Bright-ness temperature predictions differ significantly due to present diverse spectrum models, and thus a study on wave spectrum obtained inversely from brightness temperature measurements is necessary. From the ocean surface radiation data measured by polarimetric microwave radiometer, we derived an ocean wave spectrum with a wider wave number range, using the proposed two-scale model and constrained linear least-squares method. The derived ocean wave spectrum is useful for comparing with present diverse models. 展开更多
关键词 microwave radiation of OCEAN surface TWO-SCALE model OCEAN wave CURVATURE spectrum
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Characterisation of a microwave induced plasma torch for glass surface modification 被引量:3
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作者 Adam BENNETT Nan YU +4 位作者 Fengzhou FANG Marco CASTELLI Guoda CHEN Alessio BALLERI Takuya URAYAMA 《Frontiers of Mechanical Engineering》 SCIE CSCD 2021年第1期122-132,共11页
Microwave induced plasma torches find wide applications in material and chemical analysis.Investigation of a coaxial electrode microwave induced plasma(CE–MIP)torch is conducted in this study,making it available for ... Microwave induced plasma torches find wide applications in material and chemical analysis.Investigation of a coaxial electrode microwave induced plasma(CE–MIP)torch is conducted in this study,making it available for glass surface modification and polishing.A dedicated nozzle is designed to inject secondary gases into the main plasma jet.This study details the adaptation of a characterisation process for CE–MIP technology.Microwave spectrum analysis is used to create a polar plot of the microwave energy being emitted from the coaxial electrode,where the microwave energy couples with the gas to generate the plasma jet.Optical emission spectroscopy analysis is also employed to create spatial maps of the photonic intensity distribution within the plasma jet when different additional gases are injected into it.The CE–MIP torch is experimentally tested for surface energy modification on glass where it creates a super-hydrophilic surface. 展开更多
关键词 microwave induced plasma spectrum analysis surface modification
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Application of time reversal mirror technique in microwave-induced thermo-acoustic tomography system 被引量:4
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作者 CHEN GuoPing ZHAO ZhiQin +2 位作者 ZHENG WenJun NIE ZaiPing LIU QingHuo 《Science China(Technological Sciences)》 SCIE EI CAS 2009年第7期2087-2095,共9页
Microwave-induced thermo-acoustic tomography (MITAT) is a promising technique with great potential in biomedical imaging. It has both the high contrast of the microwave imaging and the high resolution of the ultrasoun... Microwave-induced thermo-acoustic tomography (MITAT) is a promising technique with great potential in biomedical imaging. It has both the high contrast of the microwave imaging and the high resolution of the ultrasound imaging. In this paper, the proportional relationship between the absorbed microwave energy distribution and the induced ultrasound source distribution is derived. Further, the time reversal mirror (TRM) technique based on the pseudo-spectral time domain (PSTD) method is applied to MITAT system. The simulation results show that high contrast and resolution can be achieved by the TRM technique based on PSTD method even for the received signals with very low signal-to-noise ratio (SNR) and the model parameter with random fluctuation. 展开更多
关键词 microwave-induced thermo-acoustic tomography (MITAT) TIME REVERSAL MIRROR (TRM) pseudo–spectrum TIME domain (PSTD)
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Mssbauer Study of Coal Desulfurization by Microwave Irradiation Combined With Manetic-Separation and Chemical Acid-Leaching
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作者 翁斯灏 王杰 《Science China Chemistry》 SCIE EI CAS 1993年第11期1289-1299,共11页
^(57)Fe Mssbauer spectroscopy was used to study the mechanism and regularity of coal desulfurization by microwave irradiation combined with magnetic-separation and with chemical acid-leaching. The results of phase ana... ^(57)Fe Mssbauer spectroscopy was used to study the mechanism and regularity of coal desulfurization by microwave irradiation combined with magnetic-separation and with chemical acid-leaching. The results of phase analyses show that the decomposing reaction of pyrite intrinsic in coal, caused by the selective dielectric heating of microwave electromagnetic energy, FeS_2→Fe_(1-x)S→FeS, consecutively progresses towards the right-hand side with increased irradiation time. The whole process of microwave desulfurization of raw coal consists of the initiation, the promotion, and the saturation stages. The optimum desulfurization efficiency for microwave irradiation combined with magnetic-separation treatment and with chemical acid-leaching treatment can be attained by appropriately controlling the irradiation time to enable the corresponding microwave treatment to lie in the promotion stage and the saturation stage, respectively. 展开更多
关键词 coal DESULFURIZATION microwave IRRADIATION magnetic-separation CHEMICAL aeid-leaching MSSBAUER spectrum.
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A NUMERICAL STUDY FOR MICROWAVE BACKSCATTERING CROSS-SECTION OF SEA SURFACE
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作者 LIU Zhi-liang HU Dun-xin +1 位作者 TIAN Ji-wei QIN Zheng-cai 《Journal of Hydrodynamics》 SCIE EI CSCD 2005年第5期546-551,共6页
Based on Tian et al. 's theoretical model of microwave scattering, by using the wind wave spectrum suggested by Fung et al. , numerical results of polarized back-scattering were calculated. The quantitative relations... Based on Tian et al. 's theoretical model of microwave scattering, by using the wind wave spectrum suggested by Fung et al. , numerical results of polarized back-scattering were calculated. The quantitative relationships between the calculated backscattering cross section and the environmental parameters, such as wind speeds, azimuthal angles and incidence angles, were studied. Compared with the traditional two-scale scattering model, the results are much more coincident with the observations under the condition of moderate incidence angles, which is very useful to make up for the two-scale model. To make the new calculation model to be used conveniently in the practice, its simplified form was proposed. 展开更多
关键词 microwave scattering model backscattering cross section of sea surface wind-wave spectrum white caps
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Measurement Quantization Describes History of Universe—Quantum Inflation, Transition to Expansion, CMB Power Spectrum
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作者 Jody A. Geiger 《Journal of High Energy Physics, Gravitation and Cosmology》 2020年第2期186-224,共39页
Developing a comprehensive model of the early universe that describes events and conditions prior to recombination has proved difficult. Using a new approach, we express Heisenberg’s uncertainty principle in terms of... Developing a comprehensive model of the early universe that describes events and conditions prior to recombination has proved difficult. Using a new approach, we express Heisenberg’s uncertainty principle in terms of measures and counts of those measures to resolve an expression consisting entirely of counts. The description allows us to resolve explicit values for discrete measures. With these values, we present new expressions describing the earliest epoch and the transition event that initiates expansion. We determine the quantity, age, density, and temperature of the cosmic microwave background (CMB). Moreover, we approach the CMB power spectrum anew, describing each mass/energy distribution, its physical significance, its peak temperature, and the effects of relativity. We do not engage in fitting or modification of the existing laws of physics. The approach is classical and correlates both quantum and cosmological phenomena with descriptive expressions that are measurable, verifiable, and falsifiable. 展开更多
关键词 COSMIC microwave Background Earliest EPOCH INFLATION Power spectrum EXPANSION QUANTUM Singularity
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Influence of Re-ions with different ionic radius in Ba_(12)ReNb_(9)O_(36) on crystal structure and microwave dielectric properties
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作者 Pengcheng Zhang Hao Li +4 位作者 Xiaoqing Chen Xing Zhang Hongcheng Yang Canbing Li Shuren Zhang 《Journal of Materiomics》 SCIE 2022年第1期104-112,共9页
The Ba_(12)ReNb_(9)O_(36)(Re=Yb,Ce,Tm,Er,Y,Ho,Dy,Gd)ceramics are synthesized by solid-phase reaction method.The phase composition,crystal structure,microstructure,and microwave dielectric properties of the ceramics ar... The Ba_(12)ReNb_(9)O_(36)(Re=Yb,Ce,Tm,Er,Y,Ho,Dy,Gd)ceramics are synthesized by solid-phase reaction method.The phase composition,crystal structure,microstructure,and microwave dielectric properties of the ceramics are investigated by X-ray diffraction,X-ray photoelectron spectroscopy,Scanning electron microscopy and Raman spectrum.The optimal microwave dielectric properties(ε_(r)=37.23,Q×f=36600 GHz,andτ_(f)=34 ppm/℃)are obtained for Ba_(12)YbNb_(9)O_(36) ceramic sintered at 1420℃for 6 h.In this system,the variation of dielectric constant is dominated by polarizability.The Q×f is mainly affected by internal strain/fluctuation of d-spacing.The variation of τ_(f) is related to the temperature coefficient of dielectric constant and the oxygen octahedron distortion.Furthermore,the reduction of Ce^(4+) ions,the relative density,linear thermal expansion coefficient,and the second phase are also important factors affecting microwave dielectric properties. 展开更多
关键词 microwave dielectric ceramic Ba_(12)ReNb_(9)O_(36) POLARIZABILITY Raman spectrum
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中法海洋卫星产品体系及风浪数据精度综述
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作者 孙从容 刁宁辉 +1 位作者 徐莹 郎姝燕 《海洋气象学报》 2024年第4期1-11,共11页
中法海洋卫星(China-France Oceanography SATellite,CFOSAT)由中国和法国联合研制,于2018年发射并已在轨运行5年多,星上的载荷包括SWIM(Surface Waves Investigation and Monitoring)波谱仪和扇形波束旋转扫描微波散射计(CFOSAT SCATte... 中法海洋卫星(China-France Oceanography SATellite,CFOSAT)由中国和法国联合研制,于2018年发射并已在轨运行5年多,星上的载荷包括SWIM(Surface Waves Investigation and Monitoring)波谱仪和扇形波束旋转扫描微波散射计(CFOSAT SCATterometer,CSCAT),提供了全球海面风场和海浪谱的大面积联合遥感观测资料。中法海洋卫星1—4级数据产品包括后向散射系数、沿轨海面风场和海浪谱、全球网格化风场和海浪谱、宽刈幅海浪、极地海冰、多星融合风场和有效波高等,为海洋环境预报、海洋灾害监测、全球气候变化研究等提供了新的数据源。文中具体介绍了中法海洋卫星产品体系以及国内外学者和机构对海风、海浪数据精度的评估结果。 展开更多
关键词 中法海洋卫星(CFOSAT) SWIM波谱仪 扇形波束旋转扫描微波散射计 海浪谱 海面风场
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多源地基遥感资料在郑州强飑线天气预警中的应用
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作者 崔慧慧 李娜 +3 位作者 李荣 王丽 张若玉 吴洁 《河南科学》 2024年第10期1505-1513,共9页
基于风廓线雷达、毫米波云雷达、微波辐射计、雨滴谱等地基遥感探测资料和常规探测资料,研究多源探测资料在郑州强飑线天气预警中的应用.结果表明:①风廓线雷达资料精细地呈现了飑线过程中冷暖平流及垂直风切变的演变,特别是监测到飑线... 基于风廓线雷达、毫米波云雷达、微波辐射计、雨滴谱等地基遥感探测资料和常规探测资料,研究多源探测资料在郑州强飑线天气预警中的应用.结果表明:①风廓线雷达资料精细地呈现了飑线过程中冷暖平流及垂直风切变的演变,特别是监测到飑线形成前1 h对流层中低层西南急流形成并增厚,深层垂直风切变增强,利于飑线的形成和组织化.②毫米波云雷达产品显示,随着飑线系统移近,云系增多增厚并向下、向上扩展,云中的含水量增大,强反射率因子接地指示降水产生.③微波辐射计反演的温度、湿度及大气不稳定指数在对流发生前后变化特征显著,在飑线临近预警中有一定的参考价值.④雨滴谱数据显示直径2 mm以下的雨滴是此次飑线降水的主要贡献者. 展开更多
关键词 强飑线 风廓线雷达 毫米波云雷达 微波辐射计 雨滴谱
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Ultra-Wideband Electromagnetic Radiation from GaAs Photoconductive Switches 被引量:2
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作者 施卫 贾婉丽 纪卫莉 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2005年第1期11-15,共5页
The experiment results of ultrawide band electromagnetic radiation with DC biased GaAs photoconductive semiconductor switch combining double ridge horn antenna triggered by high repeat frequency femto-second laser pul... The experiment results of ultrawide band electromagnetic radiation with DC biased GaAs photoconductive semiconductor switch combining double ridge horn antenna triggered by high repeat frequency femto-second laser pulse are reported.The GaAs switches are insulated by solid multi-layer transparent dielectrics and the distance of two electrodes is 3mm.The electrode material of the switch is ohmic contact through alloy technics with definite proportion of Au/Ge/Ni.This switch and double ridge horn antenna are integrated and the receive antenna is connected with the test instrument.From receiving antenna,ultra fast electrical pulse of 200ps rise time and 500ps pulse width is obtained,the repetition rate of the pulse is about 82MHz and the frequency spectrum is in the range of 4.7MHz~14GHz.The radiation characteristic of the ultrafast electrical pulse is analyzed. 展开更多
关键词 GaAs photoconductive switch ultra-wideband microwave femto-second laser pulse
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基于单比特压缩感知的光子辅助微波频谱检测方法
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作者 高嘉威 方金鹏 +2 位作者 江利中 黄勇 陈阳 《制导与引信》 2024年第3期39-45,60,共8页
提出一种基于单比特压缩感知的光子辅助微波频谱检测方法。该方法利用受激布里渊散射效应构建与未知信号频率相关的光陷波滤波器,并将构建的光陷波滤波器作用于光频梳信号产生频谱空穴,随后利用光子辅助的随机解调器对频谱空穴位置信息... 提出一种基于单比特压缩感知的光子辅助微波频谱检测方法。该方法利用受激布里渊散射效应构建与未知信号频率相关的光陷波滤波器,并将构建的光陷波滤波器作用于光频梳信号产生频谱空穴,随后利用光子辅助的随机解调器对频谱空穴位置信息进行高概率重构以实现对待测信号的频谱估计。将光子辅助的压缩感知技术应用于频谱检测,避免了对高速模数转换器的使用。此外,单比特量化的使用大幅降低了量化比特位数,减少了采样数据量,降低了后续数据的存储难度。仿真结果表明:通过控制电频梳的频率间隔,采用所提方法可以实现误差小于20 MHz的微波信号的频谱检测。 展开更多
关键词 单比特压缩感知 频谱检测 微波光子学 受激布里渊散射
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石墨炉原子吸收光谱法检测牡蛎中镉元素含量
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作者 李超男 曹振 《现代食品》 2024年第17期203-206,共4页
目的:建立石墨炉原子吸收光谱法检测牡蛎中镉元素含量的方法。方法:采用微波消解法对牡蛎进行前处理,利用石墨炉原子吸收光谱法测定,通过优化基体改进剂、灰化温度等工作参数,确定最佳的分析方法,同时加标回收验证方法的准确性和稳定性... 目的:建立石墨炉原子吸收光谱法检测牡蛎中镉元素含量的方法。方法:采用微波消解法对牡蛎进行前处理,利用石墨炉原子吸收光谱法测定,通过优化基体改进剂、灰化温度等工作参数,确定最佳的分析方法,同时加标回收验证方法的准确性和稳定性。结果:在0~2.0µg·L^(-1),方法的线性关系良好,相关系数为0.9974,检出限为0.002 mg·kg^(-1),定量限为0.004 mg·kg^(-1),加标回收率为91.0%~99.3%,相对标准偏差为0.13%~0.16%。结论:该方法操作便捷、准确、实用,精密度良好,非常适用于牡蛎中镉元素的测定。 展开更多
关键词 石墨炉原子吸收光谱法 牡蛎 微波消解
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