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941.
Laser-radiation transfer in a Markov binary mixture is compared to transfer in an equivalent homogeneous medium. Within the
framework of a small-angle approximation a system of equations that describe the angular moments of the second order (angular
dispersion) for a laser beam and the equation for laser-beam intensity is obtained. The results of the calculations show a
significant effect of the stochastic nature of the medium on the intensity and the angular structure of the laser beam.
Deceased
Institute of Applied Optics, National Academy of Sciences of Belarus, 11, Belynitskii-Birulya St., Mogilev, 272793. Translated
from Zhurnal Prikladnoi Spektroskopii, Vol. 66, No. 1, pp. 36–42, January–February, 1999. 相似文献
942.
This paper describes the application of multiple beam shearing interferometry to a position magnifying sensor. A multiple beam shearing interferometer (MBSI) with a shear plate wedged in the vertical direction produces sharp multiple beam fringes. When the lateral displacement of a point source (which gives rise to the input beam of the MBSI) or its image occurs in the horizontal direction, these fringes move vertically in a magnified manner. This characteristic was used in a position magnifying sensor to detect the displacement of a point image. The advantages of the sensor include a large displacement magnification (more than a hundred times) and a large working distance. 相似文献
943.
944.
一台14.5GHz新型高磁场高电荷态ECR离子源 总被引:3,自引:1,他引:2
自行研制成功一台14.5GHz新型高磁场高电荷态电子回旋共振(ECR)离子源.描述了该离子源结构特点、参数优化及其磁场分布,并给出了调试测量结果.该离子源轴向磁镜场在轴线上的最高磁场可达1.5T,六极永磁体在弧腔内表面磁场可达1.0T.经初步调试,可得到07+140eμA,Ar11+185eμA,Xe26+50eμA.所得结果与1998年国际上最好的ECR离子源进行了比较. 相似文献
945.
946.
用薄透镜近似空间电荷相互作用的方法研究了强束流在周期场中的传输特性.通过计算可以说明束晕的形成.同时,也为研究比K–V分布更为复杂、真实的束流分布的传输特性提供了一种新的计算方法. 相似文献
947.
M. Mühlbauer H. Daniel F.J. Hartmann P. Hauser F. Kottmann C. Petitjean W. Schott D. Taqqu P. Wojciechowski 《Hyperfine Interactions》1999,119(1-4):305-310
The classical methods used in beam cooling are hard to be adapted for a beam of short-lived elementary particles. A novel
method, the so-called frictional cooling – that is cooling a beam of low-energy charged particles by moderation in matter
and acceleration in an electrostatic field – has been shown to be feasible. In our experiments performed in 1994/1995 a beam
of short-lived particles was cooled for the first time ever. Utilizing frictional cooling on a beam of slow negative muons
we observed increase in phase space density by about one order of magnitude.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
948.
The mass attenuation coefficient (μ
m) of 662 keV gamma rays have been measured in the extended media of bakelite and perspex under different collimation conditions.
The increase in attenuation coefficient is seen with increase in sample thickness as well as with collimator size due to the
contribution of multiple scattered photons in the uncollided beam of 662 keV gamma rays. 相似文献
949.
毫米波回旋速调管磁控注入电子枪模拟计算 总被引:2,自引:1,他引:1
介绍了毫米波回旋速调管磁控注入电子枪的结构与特点。电子枪提供的电子束流性能直接影响到回旋速调管的总体参数,为保证整管的效率和输出功率,利用电子枪模拟程序对电子轨迹进行模拟计算,研究了电极形状、磁场分布以及电子轨迹与电子注参量的影响,并为磁控注入电子枪的设计提供了理论依据。 相似文献
950.
A. Pillay Narrainen L. R. Hutchings W. J. Feast R. L. Thompson I. A. Ansari N. Clarke 《Macromolecular Symposia》2005,231(1):103-109
Fréchet-type poly(arylether) first and second generation (G1 and G2 respectively) dendrons were prepared from 1-(bromomethyl)-3,5-bis(trifluoromethyl)benzene. The latter and the brominated versions of the two dendrons were successfully employed in the copper mediated living radical polymerization (LRP) of styrene-d8 giving polymers of predictable molecular weights and narrow polydispersities. Contact angle measurements and ion beam analysis were used to explore the adsorption of these materials to the air-polymer surface in blended films with unfunctionalized hydrogenous polystyrene. Although contact angle analysis indicated only modest changes in the hydrophobicity and lipophobicity of the surface, ion beam analysis clearly showed the formation of an excess layer of dendron functionalized polymer at the exposed surface that increased with increasing fluorine content. 相似文献