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小型线形可变滤光片分光的可见成像光谱仪及其特性研究   总被引:7,自引:1,他引:6  
本文设计了一种使用线形可变干涉滤光片的小型成像光谱仪。使用CCD摄像头作图像传感器,通过微动平台带动线形可变干涉滤光片,横向扫描通过面阵CCD的每个像元,每扫描一步所得到的总体图像中不同列的像元是由不同波长的单色部分像元组成,随着扫描步进,这些单色部分像元的波长随之变化,最后采用图像重构的文教是到一系列单色图像(或见光波段400-700mm)。扫描间隔由所需的单色图像的光谱分辨率和各单色图像间的波长间隔来确定。经过试验证明,此成像光谱仪充分利用了线型干涉滤光片的性能,其光谱分辨率为16nm,同后者的光谱带宽相差无几,仪器的空间分辨率由成像系统和CCD来确定,论仪器装置具有结构简单,高空间分辨率,较主光谱分辨率,扫描速度快等特点,通过一个伪装识别试验,验证了仪器的性能指标。  相似文献
2.
实际应用时燃料电池的运行条件会随时间不断地变化,因此是一个非稳态过程.本文研究了在不同的加湿条件以及反应气流量下电池的启动特性.结果表明:随着气体流量的增大,电池启动速度加快;对电池加湿有利于提高电池的启动性能.  相似文献
3.
本文采用数值模拟和实验测量相结合的方法,以叶顶间隙流的非定常流场特征为切入点,系统地研究了畸变情况下轴流压气机旋转失速的触发机理.研究结果表明:畸变影响区内叶片负载明显高于非畸变影响区;畸变影响区内逆压梯度的增大使得叶顶泄漏涡轨迹前移,当节流到一定程度时,叶顶泄漏流溢出,形成类尖脉冲扰动,类尖脉冲扰动的间歇性发展,最终诱发旋转失速.  相似文献
4.
本文自行设计了轴流压气机旋转进口畸变发生装置.基于M-G模型,建立了轴流压气机旋转畸变模型.采用数值模拟和实验测量相结合的方法研究了轴流压气机在发生旋转进口畸变情况下的失速过程.试图通过分析畸变扰动与旋转失速之间关联性来探索压气机失稳的触发机理.研究结果表明:在旋转畸变条件下,压气机旋转失速总是始发于畸变扰动位置.  相似文献
5.
The hardening of the buried oxide (BOX) layer of separation by implanted oxygen (SIMOX) silicon-on-insulator (SOI) wafers against total-dose irradiation was investigated by implanting ions into the BOX layers. The tolerance to total-dose irradiation of the BOX layers was characterized by the comparison of the transfer characteristics of SOI NMOS transistors before and after irradiation to a total dose of 2.7 Mrad(SiO2). The experimental results show that the implantation of silicon ions into the BOX layer can improve the tolerance of the BOX layers to total-dose irradiation. The investigation of the mechanism of the improvement suggests that the deep electron traps introduced by silicon implantation play an important role in the remarkable improvement in radiation hardness of SIMOX SOI wafers.  相似文献
6.
@@@@采用分子动力学方法研究了Pb液滴在Ni(100)晶面、(110)晶面和(111)晶面的铺展润湿行为。结果表明:Pb液滴在Ni(100)及(111)基底上的润湿铺展现象呈各向同性,而在Ni(110)基底上的润湿铺展现象呈明显的各向异性,且这种各向异性源于Ni(110)晶面点阵结构上Pb原子沿不同晶向的扩散机制及速度的明显差异;Pb液滴在Ni(111)晶面上铺展时,未发生表面合金化,液滴铺展动力学描述近似满足R2∝t,而液滴在(100)晶面和(110)晶面上铺展时表面产生合金化现象,铺展动力学关系近似满足R4∝t,且液滴在(100)晶面上的铺展速度高于(110)晶面上的铺展速度。  相似文献
7.
Under the condition of 60?°C and 20?min at pH 6.12, chlorpromazine hydrochloride (CPZ) could react with fluorescein isothiocyanate (FITC) to produce FITC-CPZ, which increased the π-electron density (δ) of carbon atom in FITC conjugated system and the room temperature phosphorescence (RTP) intensity of FITC. Thus, a new solid substrate room temperature phosphorimetry (SSRTP) for the determination of residual CPZ was established. The regression equation of working curve was ΔI (p)?=?4.254?+?7.906 m(CPZ) (ag spot(-1)) with the correlation coefficient (r) of 0.9990 in the range of 0.036-9.6 ag spot(-1) (corresponding concentration: 0.090-24?fg?ml(-1), sample volume: 0.40?μl spot(-1)), and the detection limit (LD) was 0.018 ag spot(-1) (corresponding concentration: 4.5?×?10(-17)?g?ml(-1)). This method with wide linear range and high sensitivity was not only used to diagnose human disease based on the correlation between the residual quantity and lethal dose of CPZ in human serum, but also used to determine residual CPZ in biological samples with the results consisting with those obtained by gas chromatography (GC), showing good accuracy. The constituent of FITC-CPZ was analyzed by GC-MS (mass spectrometry) and the reaction mechanism of SSRTP for the determination of trace CPZ was also discussed.  相似文献
8.
The photoionization and photodissociation of 1,4-dioxane have been investigated with a reflectron time-of-flight photoionization mass spectrometry and a tunable vacuum ultraviolet synchrotron radiation in the energy region of 8.0-15.5 eV. Parent ion and fragment ions at m/z 88, 87, 58, 57, 45, 44, 43, 41, 31, 30, 29, 28 and 15 are detected under supersonic conditions. The ionization energy of DX as well as the appearance energies of its fragment ions C4H7O2+, C3H6O+, C3H5O+, C2H5O+, C2H4O+, C2H3O+, C3H5+, CH3O+, C2H6+, C2H5+/CHO+, C2H4+ and CH3+ was determined from their photoionization efficiency curves. The optimized structures for the neutrals, cations, transition states and intermediates related to photodissociation of DX are characterized at the B3LYP/6-31+G(d,p) level and their energies are obtained by G3B3 method. Possible dissociative channels of the DX are proposed based on comparison of experimental AE values and theoretical predicted ones. Intramolecular hydrogen migrations are found to be the dominant processes in most of the fragmentation pathways of 1,4-dioxane.  相似文献
9.
A Wigner crystal formed with trapped ions can undergo a structural phase transition, which is determined only by the mechanical conditions on a classical level. Instead of this classical result, we show that through consideration of quantum and thermal fluctuation, a structural phase transition can be driven solely by a change in the system's temperature. We determine a finite-temperature phase diagram for trapped ions using the renormalization group method and the path integral formalism, and propose an experimental scheme to observe the predicted temperature-driven structural phase transition, which is well within the reach of the current ion trap technology.  相似文献
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