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201.
By solving time-dependent Schrödinger equation, the dependence of photoelectron energy spectra on the binding energy of targets, wavelength and intensity of laser pulse is exhibited and a scaling law of kinetic energy spectra of both the direct and the rescattered photoelectrons is concluded. The scaling law provides a convenient tool to determine the equivalent photoionization process of various atoms or molecules in various laser fields. The verification of the scaling law by independent methods provides an incontestable support to the validity of the scaling law. 相似文献
202.
四频激光陀螺和频与温度关系的研究 总被引:4,自引:1,他引:4
研究了四频激光陀螺和频与温度之间的关系。通过静态和动态实验 ,证明了和频与温度的线性关系 ,并得到了拟合直线表达式。结果表明 ,和频与温度具有较好的线性关系 ,和频可作为温度测量的计量 ,而且具有较好的重复性。由于测量频率的精度较高 ,故由和频测量温度具有很高的分辨率。 相似文献
203.
Thermal analysis has been employed to measure changes of the heat capacity of ferromagnetic materials such as alloys in the region of the Curie temperature. Thermal response for these materials is usually small in this region. The necessary increase in sensitivity was achieved by applying temperature modulation. Results obtained by this technique including temperature-modulated differential thermal analysis simultaneously with A.C. thermomagnetometry are presented. 相似文献
204.
205.
Jong-Ho Park 《Applied Surface Science》2010,256(17):5528-5532
Oxygen-selective adsorbents were prepared by two different methods, hydrothermal and sol-gel methods. The adsorption and desorption characteristics of these adsorbents were compared in terms of stability and sorption capacity. The sorbents prepared by the sol-gel method showed better cyclic stability and higher adsorption capacity than that prepared by the hydrothermal method because the sol-gel method entrapped well the barium peroxide.Relaxation time for adsorption ranged from 4 to 9 min depending on the preparation methods and that for desorption was 6 min regardless of the preparation methods. Breakthrough experiment with the sorbent prepared by the sol-gel method was performed. The adsorption breakthrough curves at 600 °C showed two plateau regions. One was at about 3.5%, and the other was 20%. The first plateau region is related to the sharp transition point of the oxygen adsorption isotherm. Though the relaxation time for adsorption was 6 min, the time required from the end of the first plateau to the beginning of the second plateau was just 2 min. During the desorption, a plateau region at 3.5% of oxygen concentration was observed regardless of the desorption flow rate. 相似文献
206.
D.Q. Peng 《Applied Surface Science》2010,256(24):7522-7529
Ammonia-gas nitriding of AISI 304 austenitic stainless steel was studied at temperatures higher than 800 °C using SEM and X-ray diffraction. The result showed that S-phase, an expanded austenite, was formed even at such high temperatures due to a high nitriding potential of ammonia gas. The equilibrium phase, CrN was formed through a decomposition of S-layer in two different modes; the one was through continuous precipitation of particles at the surface-side of S-layer due to a higher nitriding potential; the other through a discontinuous(-like) precipitation at the austenite interface-side, producing a fine lamellar structure of austenite and CrN. The γ-phase in the surface-side resulting from the precipitation of CrN particles subsequently transformed into Fe4N because of a fast enrichment of N atoms and a limited mobility of Cr atoms at the surface-side. A coarse lamellar structure made of austenite and Cr2N was developed in front of fine lamellae composed of austenite and CrN by the decomposition of supersaturated austenite through a discontinuous precipitation via grain boundary movement. 相似文献
207.
Yanli Qin 《Applied Surface Science》2010,257(3):817-822
Hydrogenated amorphous and microcrystalline silicon films were deposited by inductively coupled plasma chemical vapor deposition (ICP-CVD) at low substrate temperatures using H2-diluted SiH4 as a source gas. High-density plasma generated by inductively coupled excitation facilitates the crystallization of silicon films at low temperatures, and microcrystalline silicon films were obtained at the substrate temperature as low as 180 °C. The columnar structure of the films becomes more and more compact with an increase of their crystallinity. The reduction of hydrogen content in the films causes a narrowing of the optical bandgap and an enhancement of the absorption with increasing the substrate temperature. The microcrystalline silicon films show two electronic transport mechanisms: one is related to the density of state distribution in the temperature region near room temperature and the other is the variable range hopping between localized electronic states close to the Fermi level below 170 K. A reasonable explanation is presented for the dependence of the optoelectronic properties on the microstructure of the silicon films. The films prepared at a substrate temperature of 300 °C have highly crystalline and compact columnar structure, high optical absorption coefficient and electrical conductivity, and a low hydrogen content of 3.8%. 相似文献
208.
《Physics letters. A》2020,384(9):126186
The phase diagrams and magnetic properties of double perovskite have been studied by using Monte Carlo simulation based on the heat bath algorithm. The ground-state diagrams of the compound have been calculated for different combinations of system parameters. The diagrams obtained are very rich and they give an idea of all the most stable configurations. The effects of the exchange interactions and the crystal field on the phase diagrams and magnetic properties of the system have been examined. A number of interesting phenomena have been observed such as the compensation temperature, the first and second order phase transitions, the critical triple point and the terminal critical point. 相似文献
209.
介绍了一种新型的具有双参量测量功能的光纤布喇格光栅传感器.该传感器采用了特殊的结构,安装了两个不同中心波长的光纤布喇格光栅,可以实现两曲面之间狭小间隙的微小位移和温度的同时测量.实验表明,该传感器结构紧凑、体积小,具有良好的重复性和稳定性,位移测量误差不超过±10 μm,温度测量误差不超过±2℃. 相似文献
210.