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微波除冰效率关键技术研究 被引量:41
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作者 焦生杰 唐相伟 +1 位作者 高子渝 王强 《中国公路学报》 EI CAS CSCD 北大核心 2008年第6期121-126,共6页
为了提高微波除冰效率,实现冬季道路快速微波除冰,对影响微波除冰效率的关键因素(微波频率和道路材料)进行了仿真和试验研究。通过对微波除冰效率的分析,提出了以冰层和路面结合处温度到达0℃所需的时间作为微波除冰效率的判定指... 为了提高微波除冰效率,实现冬季道路快速微波除冰,对影响微波除冰效率的关键因素(微波频率和道路材料)进行了仿真和试验研究。通过对微波除冰效率的分析,提出了以冰层和路面结合处温度到达0℃所需的时间作为微波除冰效率的判定指标。建立了微波除冰模型,运用CST、Matlab和ANSYS仿真软件,得出了微波除冰效率与微波频率、不同介质损耗角正切的道路材料关系,并通过试验验证了仿真结论的合理性。研究结果表明:相对于2.45GHz微波,5.8GHz微波能够提高微波除冰效率4~6倍;相对于普通沥青混凝土路面,使用铁磁性材料加铺层能够提高除冰效率3~5倍。 展开更多
关键词 机械工程 微波除冰 仿真和试验 关键技术 磁控管 道路养护
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磁控管的研究现状与发展趋势 被引量:26
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作者 吴群 《哈尔滨工业大学学报》 EI CAS CSCD 北大核心 2000年第5期9-12,共4页
磁控管是一种效率最高的大功率微波源 ,不仅在军事领域得到了广泛的应用 ,在民用领域也得到了广泛的应用 .实践证明 ,从输出功率、效率和可靠性的观点考虑 ,当前的微波半导体器件是难以胜任的 .在今后的相当长的一段时期内 ,磁控管仍将... 磁控管是一种效率最高的大功率微波源 ,不仅在军事领域得到了广泛的应用 ,在民用领域也得到了广泛的应用 .实践证明 ,从输出功率、效率和可靠性的观点考虑 ,当前的微波半导体器件是难以胜任的 .在今后的相当长的一段时期内 ,磁控管仍将在大功率和高频率应用中继续充当主要角色 .对磁控管研究中出现的新技术和新方法进行了总结 ,提出了高效率大功率磁控管研究中所面临的问题 ,并展望了未来的发展趋势 . 展开更多
关键词 磁控管 大功率微波源 微波器件 微波电子管
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Influence of the sputtering pressure on the properties of transparent conducting zirconium-doped zinc oxide films prepared by RF magnetron sputtering 被引量:16
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作者 刘汉法 张化福 +1 位作者 类成新 袁长坤 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2009年第2期17-20,共4页
Transparent conducting zirconium-doped zinc oxide films with high transparency and relatively low resistivity have been successfully prepared on water-cooled glass substrate by radio frequency magnetron sputtering at ... Transparent conducting zirconium-doped zinc oxide films with high transparency and relatively low resistivity have been successfully prepared on water-cooled glass substrate by radio frequency magnetron sputtering at room temperature. The Ar sputtering pressure was varied from 0.5 to 3 Pa. The crystallinity increases and the electrical resistivity decreases when the sputtering pressure increases from 0.5 to 2.5 Pa. The cystallinity decreases and the electrical resistivity increases when the sputtering pressure increases from 2.5 to 3 Pa. When the sputtering pressure is 2.5 Pa, it is obtained that the lowest resistivity is 2.03 x 10^-3Ω .cm with a very high transmittance of above 94%. The deposited films are polycrystalline with a hexagonal structure and a preferred orientation perpendicular to the substrate. 展开更多
关键词 zirconium-doped zinc oxide films transparent conducting films magnetron sputtering sputtering pressure
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变频微波炉电源用LLC谐振变换器 被引量:17
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作者 王春芳 徐勤超 《电工技术学报》 EI CSCD 北大核心 2012年第6期103-109,共7页
研制了一款专为变频微波炉中磁控管供电的高频软开关电源。采用倍压输出式LLC谐振变换器作为该电源的主电路,并用基波分析法建立了其稳态基波等效电路模型;对其直流增益、谐振电流及零电压导通条件等进行了分析,并对高频变压器的电压比... 研制了一款专为变频微波炉中磁控管供电的高频软开关电源。采用倍压输出式LLC谐振变换器作为该电源的主电路,并用基波分析法建立了其稳态基波等效电路模型;对其直流增益、谐振电流及零电压导通条件等进行了分析,并对高频变压器的电压比、品质因数、励磁电感、谐振电感及谐振电容等核心参数进行了优化设计。仿真和实验表明所建立的稳态电路模型及其理论分析是正确的,给出的谐振网络参数及其优化设计是正确的,这对于分析、研究和改进变频微波炉电源的设计及指导生产具有现实意义。 展开更多
关键词 微波炉 磁控管 LLC谐振变换器 零电压开关 基波分析法
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Preparation of Ti_2AlC MAX Phase Coating by DC Magnetron Sputtering Deposition and Vacuum Heat Treatment 被引量:11
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作者 Zongjian Feng Peiling Ke Aiying Wang 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2015年第12期1193-1197,共5页
Due to the excellent corrosion resistance and high irradiation damage resistance,Ti 2AlC MAX phase is considered as a candidate for applications as corrosion resistant and irradiation resistant protective coating.MAX ... Due to the excellent corrosion resistance and high irradiation damage resistance,Ti 2AlC MAX phase is considered as a candidate for applications as corrosion resistant and irradiation resistant protective coating.MAX phase coatings can be fabricated through firstly depositing a coating containing the three elements M,A,and X close to stoichiometry of the MAX phases using physical vapor deposition,followed by heat treatment in vacuum.In this work,Ti-Al-C coating was prepared on austenitic stainless steels by reactive DC magnetron sputtering with a compound Ti (50)Al (50) target,and CH4 used as the reactive gas.It was found that the as-deposited coating is mainly composed of Ti 3AlC antiperovskite phase with supersaturated solid solution of Al.Additionally,the ratio of Ti/Al remained the same as that of the target composition.Nevertheless,a thicker thermally grown Ti 2AlC MAX phase coating was obtained after being annealed at 800℃ in vacuum for 1 h.Meanwhile,the ratio of Ti/Al became close to stoichiometry of Ti 2AlC MAX phases.It can be understood that owing to the higher activity of Al,it diffused quickly into the substrate during annealing,and then more stable Ti 2AlC MAX phases transformed from the Ti 3AlC antiperovskite phase. 展开更多
关键词 TI2ALC MAX phase COATING magnetron sputtering Microstructure
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Synthesis and properties of Cr-Al-Si-N films deposited by hybrid coating system with high power impulse magnetron sputtering (HIPIMS) and DC pulse sputtering 被引量:11
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作者 Min Su KANG Tie-gang WANG +2 位作者 Jung Ho SHIN Roman NOWAK Kwang Ho KIM 《中国有色金属学会会刊:英文版》 CSCD 2012年第S3期729-734,共6页
The CrN and Cr-Al-Si-N films were deposited on Si wafer and SUS 304 substrates by a hybrid coating system with high power impulse magnetron sputtering (HIPIMS) and a DC pulse sputtering using Cr and AlSi targets under... The CrN and Cr-Al-Si-N films were deposited on Si wafer and SUS 304 substrates by a hybrid coating system with high power impulse magnetron sputtering (HIPIMS) and a DC pulse sputtering using Cr and AlSi targets under N2/Ar atmosphere.By varying the sputtering current of the AlSi target in the range of 0-2.5 A,both the Al and Si contents in the films increased gradually from 0 to 19.1% and 11.1% (mole fraction),respectively.The influences of the AlSi cathode DC pulse current on the microstructure,phase constituents,mechanical properties,and oxidation behaviors of the Cr-Al-Si-N films were investigated systematically.The results indicate that the as-deposited Cr-Al-Si-N films possess the typical nanocomposite structure,namely the face centered cubic (Cr,Al)N nano-crystallites are embedded in the amorphous Si3N4 matrix.With increasing the Al and Si contents,the hardness of the film first increases from 20.8 GPa for the CrN film to the peak value of 29.4 GPa for the Cr0.23Al0.14Si0.07 N film,and then decreases gradually.In the meanwhile,the Cr0.23Al0.14Si0.07N film also possesses excellent high-temperature oxidation resistance that is much better than that of the CrN film at 900 or 1000 °C. 展开更多
关键词 Cr-Al-Si-N film high power IMPULSE magnetron SPUTTERING DC pulsed SPUTTERING high-temperature oxidation resistance
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Influences of working pressure on properties for TiO_2 films deposited by DC pulse magnetron sputtering 被引量:11
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作者 ZHANG Can DING Wanyu +2 位作者 WANG Hualin CHAI Weiping JU Dongying 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2009年第6期741-744,共4页
TiO2 films were deposited at room temperature by DC pulse magnetron sputtering system.The crystalline structures,morphological features and photocatalytic activity of TiO2 films were systematically investigated by X-r... TiO2 films were deposited at room temperature by DC pulse magnetron sputtering system.The crystalline structures,morphological features and photocatalytic activity of TiO2 films were systematically investigated by X-ray diffraction(XRD),atomic force microscopy(AFM) and ultraviolet spectrophotometer,respectively.The results indicated that working pressure was the key deposition parameter in?uencing the TiO2 film phase composition at room temperature,which directly affected its photocatalytic activity.With increasing working pressure,the target self-bias decreases monotonously.Therefore,low temperature TiO2 phase(anatase) could be deposited with high working pressure.The anatase TiO2 films deposited with 1.4 Pa working pressure displayed the highest photocatalytic activity by the decomposition of Methyl Orange solution,which the degradation rate reached the maximum(35%) after irradiation by ultraviolet light for 1 h. 展开更多
关键词 TiO2 film ANATASE UV induced photocatalysis DC pulse magnetron sputtering
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Mechanical,Microstructural and Tribological Properties of Reactive Magnetron Sputtered Cr-Mo-N Films 被引量:11
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作者 Dongli Qi Hao Lei +3 位作者 Tiegang Wang Zhiliang Pei Jun Gong Chao Sun 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2015年第1期55-64,共10页
The Cr-Mo-N films were deposited on high speed steel(HSS) substrates by a DC reactive magnetron sputtering equipment coupled with two horizontal magnetron sources.The effects of substrate negative bias voltage(Vb)... The Cr-Mo-N films were deposited on high speed steel(HSS) substrates by a DC reactive magnetron sputtering equipment coupled with two horizontal magnetron sources.The effects of substrate negative bias voltage(Vb),substrate temperature(Ts) and gas flow ratio(R= N2/(N2+ Ar)) on the microstructure,morphology,as well as the mechanical and tribological properties of the Cr-Mo-N films were investigated by virtue of X-ray diffraction(XRD) analysis,X-ray photoelectron spectroscopy(XPS),field emission scanning electron microscopy(FESEM),atomic force microscopy(AFM),nano-indentation test,ball-on-disk tribometer,and Rockwell indenter et al.With increasing Vbto-100 V,the preferred orientation of the films changed from(111) to(200) and their mechanical and tribological properties were improved gradually,too.It was also found that Tsgave a significant effect on mechanical property enhancement.When the Tsreached 300 ℃,the film obtained the highest hardness and effective elastic modulus of approximately 30.1 and 420.5 GPa,respectively and its critical load increased to about 54 N.With increasing R,the phase transformation from body-centered-cubic(bcc) Cr and hexagonal CrMoNxmultiphase to single face-centered-cubic(fcc) solid solution phase was observed.The correlations between values of hardness(H),effective elastic modulus(E*),HIE*,H3/E*2,elastic recovery(1/14) and tribological properties of the films were also investigated.The results showed that the elastic recovery played an important role in the tribological behavior. 展开更多
关键词 Cr-Mo-N films DC magnetron sputtering Hardness CRI
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Influence and determinative factors of ion-to-atom arrival ratio in unbalanced magnetron sputtering systems 被引量:8
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作者 Jun Zhou Zhe Wu Zhanhe Liu 《Journal of University of Science and Technology Beijing》 CSCD 2008年第6期775-781,共7页
Low pressure sputtering with a controlled ratio of ion flux to deposited atom flux at the condensing surface is one of the main directions of development of magnetron sputtering methods. Unbalanced magnetron sputterin... Low pressure sputtering with a controlled ratio of ion flux to deposited atom flux at the condensing surface is one of the main directions of development of magnetron sputtering methods. Unbalanced magnetron sputtering, by producing dense secondary plasma around the substrate, provides a high ion current density. The closed-field unbalanced magnetron sputtering system (CFUBMS) has been established as a versatile technique for high-rate deposition high-quality metal, alloy, and ceramic thin films. The'key factor in the CFUBMS system is the ability to transport high ion currents to the substrate, which can enhance the formation of full dense coatings at relatively low value homologous temperature. The investigation shows that the energy of ions incidenced at the substrate and the ratio of the flux of these ions to the flux of condensing atoms are the fundamental parameters in determining the structure and properties of films produced by ion-assisted deposition processes. Increasing ion bombardment during deposition combined with increasing mobility of the condensing atoms favors the formation of a dense microstructure and a smooth surface. 展开更多
关键词 magnetron sputtering closed-field unbalanced magnetron sputtering system (CFUBMS) ion-to-atom ratio unbalancedmagnetron sputtering
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LLC谐振式磁控管供电电源的研究 被引量:12
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作者 徐勤超 王春芳 李从洋 《电力电子技术》 CSCD 北大核心 2010年第10期106-108,共3页
研制了一台零电压软开关电源,其目的是代替微波炉中工频变压器和半波倍压整流电路,为磁控管供电。用LLC谐振变换器作为电源主电路,以dsPIC单片机为核心设计了电源的控制系统,并通过改变主电路开关变频率控制法实现了电源输出电压和输出... 研制了一台零电压软开关电源,其目的是代替微波炉中工频变压器和半波倍压整流电路,为磁控管供电。用LLC谐振变换器作为电源主电路,以dsPIC单片机为核心设计了电源的控制系统,并通过改变主电路开关变频率控制法实现了电源输出电压和输出功率的调节。实验结果表明开关频率变动范围内,该电源可安全可靠地实现软开关控制,输出电压完全满足磁控管运行需求,磁控管输出功率可实现连续可调。 展开更多
关键词 谐振变换器 磁控管 单片机 变频调制
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Influence of Nitrogen Flow Ratio on the Microstructure, Composition, and Mechanical Properties of DC Magnetron Sputtered Zr-B-O-N Films 被引量:10
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作者 Tie-Gang Wang Yanmei Liu +2 位作者 Tengfei Zhang Doo-In Kim KwanKHo Kim 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2012年第11期981-991,共11页
Nanocrystalline ZrB2 film and nanocomposite Zr-B-O-N films were prepared by non-reactive as well as re- active magnetron sputtering techniques, respectively. By means of X-ray diffraction analysis, electron probe micr... Nanocrystalline ZrB2 film and nanocomposite Zr-B-O-N films were prepared by non-reactive as well as re- active magnetron sputtering techniques, respectively. By means of X-ray diffraction analysis, electron probe microanalysis, X-ray photoelectron spectroscopy, and scanning electron microscopy, the influence of nitrogen flow ratio on the film microstructure and characteristics were investigated systematically, including the depo- sition rate, chemical compositions, phase constituents, grain size, chemical bonding, as well as cross-sectional morphologies. Meanwhile, the hardness and adhesion of above films were also evaluated by micro-indentation method and a scratch tester. With increasing the nitrogen flow ratio, the deposition rate of above films de- creased approximately linearly, whereas the contents of N and O in the films increased gradually and tended to saturation. Moreover, the film microstructure was also altered gradually from a fine columnar microstructure to a featureless glass-structure. As the nitrogen flow ratio was 11.7%, the Zr-B-O-N film possessed an typical nanocomposite structure and presented good mechanical properties. During the process of reactive sputtering of metal borides, the introduction of nitrogen can show a pronounced suppression of columnar grain growth and strong nanocomposite structure forming ability. 展开更多
关键词 FILMS DC magnetron sputtering NANOCOMPOSITE MICROHARDNESS ADHESION
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Effects of substrate temperature and deposition time on the morphology and corrosion resistance of FeCoCrNiMo0.3 high-entropy alloy coating fabricated by magnetron sputtering 被引量:11
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作者 Chun-duo Dai Yu Fu +1 位作者 Jia-xiang Guo Cui-wei Du 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2020年第10期1388-1397,共10页
The effects of substrate temperature and deposition time on the morphology and corrosion resistance of FeCoCrNiMo0.3 coating fabricated by magnetron sputtering were investigated by scanning electron microscopy and ele... The effects of substrate temperature and deposition time on the morphology and corrosion resistance of FeCoCrNiMo0.3 coating fabricated by magnetron sputtering were investigated by scanning electron microscopy and electrochemical tests.The FeCoCrNiMo0.3 coating was mainly composed of the face-centered cubic phase.High substrate temperature promoted the densification of the coating,and the pitting resistance and protective ability of the coating in 3.5wt%NaCl solution was thus improved.When the deposition time was prolonged at 500℃,the thickness of the coating remarkably increased.Meanwhile,the pitting resistance improved as the deposition time increased from 1 to 3 h;however,further improvement could not be obtained for the coating sputtered for 5 h.Overall,the pitting resistance of the FeCoCrNiMo0.3 coating sputtered at 500℃for 3 h exceeds those of most of the reported high-entropy alloy coatings. 展开更多
关键词 high-entropy alloy coating magnetron sputtering MICROSTRUCTURE CORROSION
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Effect of oxygen flow rate on the properties of SiO_x films deposited by reactive magnetron sputtering 被引量:7
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作者 赖发春 李明 +2 位作者 王海千 姜友松 宋亦周 《Chinese Optics Letters》 SCIE EI CAS CSCD 2005年第8期490-493,共4页
SiOx (x = 0-2) films were deposited on BK-7 substrates by a low frequency reactive magnetron sputtering system with the oxygen flow rate (OFR) changing from 0 to 30 sccm. The samples were characterized by atomic f... SiOx (x = 0-2) films were deposited on BK-7 substrates by a low frequency reactive magnetron sputtering system with the oxygen flow rate (OFR) changing from 0 to 30 sccm. The samples were characterized by atomic force microscopy, spectrophotometer, and X-ray photoelectron spectroscopy. The extinction coefficient and refractive index decrease, while the optical transmittance increases with the increase of OFR from 0 to 17 sccm. The root mean square surface roughness has a maximum at 10 sccm OFR. The highest deposition rate is at 15 sccm OFR. Our results show that the films deposited at 20 sccm OFR are stoichiometric silica with relatively high deposition rate, low extinction coefficient, and low surface roughness. Therefore, a precise control of OFR is very important to obtain high quality films for optical applications. 展开更多
关键词 Atomic force microscopy Light extinction magnetron sputtering OPACITY Oxygen Refractive index SILICA Silicon compounds SPECTROPHOTOMETERS Surface roughness X ray photoelectron spectroscopy
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Preparation and properties of tungsten-doped indium oxide thin films 被引量:9
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作者 Li, Yuan Wang, Wenwen +1 位作者 Zhang, Junying Wang, Rongming 《Rare Metals》 SCIE EI CAS CSCD 2012年第2期158-163,共6页
Tungsten-doped indium oxide (IWO) thin films were deposited on glass substrate by DC reactive magnetron sputtering. The effects of sputtering power and growth temperature on the structure, surface morphology, optical ... Tungsten-doped indium oxide (IWO) thin films were deposited on glass substrate by DC reactive magnetron sputtering. The effects of sputtering power and growth temperature on the structure, surface morphology, optical and electrical properties of IWO thin films were investigated. The thickness and surface morphology of the films are both closely dependent on the sputtering power and the substrate temperature. The transparency of the films decreases with the increase of the sputtering power but is not seriously influenced by substrate temperature. All the IWO thin film samples have high transmittance in near-infrared spectral range. With either the sputtering power or the growth temperature increases, the resistivity of the film decreases at the beginning and increases after the optimum parameters. The as-deposited IWO films with minimum resistivity of 6.4 10 4 cm were obtained at a growth temperature of225 C and sputteringpower of 40 W, with carrier mobility of 33.0 cm 2 V 1 s 1 and carrier concentration of 2.8 10 20 cm 3 and the average transmittance of about 81% in near-infrared region and about 87% in visible region. 展开更多
关键词 In 2 O 3 : W thin film DC magnetron sputtering substrate temperature sputtering current optical and electrical properties
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A stretchable,asymmetric,coaxial fiber-shaped supercapacitor for wearable electronics 被引量:10
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作者 Hua Yuan Guang Wang +3 位作者 Yuxing Zhao Yang Liu Yang Wu Yuegang Zhang 《Nano Research》 SCIE EI CAS CSCD 2020年第6期1686-1692,共7页
Nano Research volume 13,pages1686–1692(2020)Cite this article 210 Accesses 1 Citations Metrics details Abstract Fiber-shaped supercapacitors(FSCs),owing to their high-power density and feasibility to be integrated in... Nano Research volume 13,pages1686–1692(2020)Cite this article 210 Accesses 1 Citations Metrics details Abstract Fiber-shaped supercapacitors(FSCs),owing to their high-power density and feasibility to be integrated into woven clothes,have drawn tremendous attentions as a key device for flexible energy storage.However,how to store more energy while withstanding various types of mechanical deformation is still a challenge for FSCs.Here,based on a magnetron sputtering method,different pseudocapacitive materials are conformally coated on self-supported carbon nanotube aligned films.This fabrication approach enables a stretchable,asymmetric,coaxial fiber-shaped supercapacitors with high performance.The asymmetric electrode configuration that consists of CNT@NiO@MnOx cathode and CNT@Fe2O3 anode successfully extends the FSC’s electrochemical window to 1.8 V in an aqueous electrolyte.As a result,a high specific capacitance of 10.4 F·cm^−3 is achieved at a current density of 30 mA·cm^−3 corresponding to a high energy density of 4.7 mWh·cm^−3.The mechanical stability of the stretchable FSC is demonstrated with a sustainable performance under strains up to 75%and a capacitance retention of 95%after 2,000 cycles under 75%strain. 展开更多
关键词 fiber SUPERCAPACITOR asymmetric configuration coaxial magnetron sputtering pseudocapacitive material
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粒子模拟软件吸收边界的研究 被引量:6
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作者 胡旻 祝大军 +2 位作者 刘大刚 周俊 刘盛纲 《强激光与粒子束》 EI CAS CSCD 北大核心 2006年第8期1315-1318,共4页
实现了时域有限差分法的Gedney完全匹配层吸收边界条件,并进行了数值验证和参数优化。从结果可以看出其有较低的反射,性能优良;对吸收媒质厚度和电导率分布阶数的参数优化结果与Gedney经验值基本一致。将此吸收边界模块加入到国产粒子... 实现了时域有限差分法的Gedney完全匹配层吸收边界条件,并进行了数值验证和参数优化。从结果可以看出其有较低的反射,性能优良;对吸收媒质厚度和电导率分布阶数的参数优化结果与Gedney经验值基本一致。将此吸收边界模块加入到国产粒子模拟软件CHIPIC中,同美国商业粒子模拟软件MAGIC相比有更好的吸收效果。通过对2维极坐标下磁控管的模拟,证明了此吸收边界具有实际应用价值。 展开更多
关键词 吸收边界 完全匹配层(PML) PIC模拟 磁控管
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微波法大功率稳定快速沉积CVD金刚石膜 被引量:6
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作者 黄建良 汪建华 《武汉工程大学学报》 CAS 2007年第4期63-66,共4页
为了提高微波等离子体化学气相沉积CVD金刚石膜的速率,通过对微波源的磁控管、装置的冷却系统及真空密封技术三方面的改进,当微波频率为2.45 GHz、输出有效功率为6.0 kW以上时,装置能够长期稳定地运行;并在微波输入功率4.5 kW、CH4质量... 为了提高微波等离子体化学气相沉积CVD金刚石膜的速率,通过对微波源的磁控管、装置的冷却系统及真空密封技术三方面的改进,当微波频率为2.45 GHz、输出有效功率为6.0 kW以上时,装置能够长期稳定地运行;并在微波输入功率4.5 kW、CH4质量分数1.2%、气体流量150 SCCM、沉积气压9.5 kPa、基片温度(900±10)°C、沉积时间240 h的沉积工艺条件下(衬底上加上-150 V偏压),成功地在硅片上快速沉积出了厚度为500μm的金刚石厚膜,平均沉积速率为2.1μm/h,沉积膜的拉曼光谱图和SEM照片表明沉积出金刚石膜的质量很好. 展开更多
关键词 金刚石膜 微波 化学气相沉积 装置 磁控管
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基于自激振荡器模型的辐射源个体识别方法 被引量:9
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作者 许丹 徐海源 +1 位作者 卢启中 周一宇 《信号处理》 CSCD 北大核心 2008年第1期122-126,共5页
辐射源指纹识别也称为特定辐射源识别(SEI),是指通过对接收信号进行特征测量,确定产生信号的辐射源个体,是电子战、电磁环境监视等领域的关键技术之一。本文针对自激振荡类型的发射机,从射频振荡器的等效电路模型出发。提出了一种模型... 辐射源指纹识别也称为特定辐射源识别(SEI),是指通过对接收信号进行特征测量,确定产生信号的辐射源个体,是电子战、电磁环境监视等领域的关键技术之一。本文针对自激振荡类型的发射机,从射频振荡器的等效电路模型出发。提出了一种模型化的辐射源个体识别方法。仿真结果表明,该模型化方法扩展了传统的特征定义,集成信号瞬时频率、瞬时带宽的相关信息,具有良好的分类能力。在调制电压发生较大变化时,该方法能弥补传统上升沿、下降沿时延测量方法的不足。 展开更多
关键词 特定辐射源识别 无意调制 辐射源指纹 磁控管 频推效应
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Corrosion and wear resistance of AZ31 Mg alloy treated by duplex process of magnetron sputtering and plasma electrolytic oxidation 被引量:10
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作者 Bing-jian WEI Yu-lin CHENG +2 位作者 Yuan-yuan LIU Zhun-da ZHU Ying-liang CHENG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2021年第8期2287-2306,共20页
In order to improve the wear and corrosion resistance of AZ31 magnesium alloy,a magnetron-sputtered Al layer with a thickness of 11μm was firstly applied on the alloy,and then treated by plasma electrolytic oxidation... In order to improve the wear and corrosion resistance of AZ31 magnesium alloy,a magnetron-sputtered Al layer with a thickness of 11μm was firstly applied on the alloy,and then treated by plasma electrolytic oxidation(PEO)in an aluminate and silicate electrolytes,respectively.The performance of PEO coatings was investigated by dry sliding wear and electrochemical corrosion tests.The aluminate coating exhibits excellent wear resistance under both 10 and 20 N loads.The silicate coating only shows low wear rate under 10 N,but it was destroyed under 20 N.Corrosion tests show that the Al layer after magnetron sputtering treatment alone cannot afford good protection to the Mg substrate.However,the duplex layer of PEO/Al can significantly improve the corrosion resistance of AZ31 alloy.Electrochemical tests show that the aluminate and silicate coatings have corrosion current densities of-1.6×10^(-6) and-1.1×10^(-6) A/cm^(2),respectively,which are two orders lower than that of the un-coated AZ31 alloy.However,immersion tests and electrochemical impedance spectroscopy(EIS)show that the aluminate coating exhibits better long-term corrosion protection than silicate coating. 展开更多
关键词 AZ31 magnesium alloy magnetron sputtering plasma electrolytic oxidation dry sliding wear CORROSION
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医用直线加速器磁控管更换技术探讨 被引量:9
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作者 万久庆 《医疗卫生装备》 CAS 2006年第10期46-47,共2页
在医用直线加速器中通常都采用磁控管作为微波功率源。叙述了医用直线加速器中磁控管的结构及工作原理,并重点介绍在更换磁控管过程中需要注意的技术细节和对相关参数的调整。
关键词 磁控管 医用直线加速器 微波源
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