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161.
镱的原子吸收分析进展 总被引:1,自引:0,他引:1
米瑞华 《光谱学与光谱分析》1992,12(2):105-110
本文对近些年来用电热原子吸收和火焰原子吸收测定镱时,为提高镱的灵敏度而采用的各种方法进行总结评述。 相似文献
162.
以目前国际上极为活跃开展的暗物质探测、无中微子双 衰变研究为例,评述了高纯锗探测器的重要性及其广泛的应用前景。介绍了己开展的高纯锗单晶、探测器制备的关键技术研究进展:合作单位已研制出了用于高纯锗单晶材料制备的区熔炉、单晶炉;并制备出直径为20 50 cm、纯度为12N(< 41011 atoms/cm3)、位错< 5000 atoms/cm2 的锗单晶;掌握了高纯锗探测器(平面型、同轴型)制备的关键技术,用进口高纯锗单晶材料制备出的同轴型高纯锗探测器对射线的能量分辨率及探测效率均达到进口产品指标,使用自制的12N 高纯锗单晶材料己制备出平面型高纯锗探测器。呼吁加速高纯锗研制的自主创新步伐,尽早实现其国产化目标。The article reviews importance and wide applications of HPGe detector, especially the application on the dark matter search experiment and double beta decay experiment. The research progress on the Highpurity germanium single crystal and HPGe detector in China has been introduced. The cooperation partner developed new type zone-refining furnace and single crystal furnace. The ultra-purity germanium single crystal with 20~50 cm, purity up to 12N(net impurity concentration is less than 41011 atoms/cm3), and dislocation less than 5 000 /cm3 was prepared. The key technologies for preparing planar and coaxial HPGe detector were mastered. The coaxial detector, which has been made of imported ultra-purity germanium single crystal has excellent energy resolution and efficiency as the imported commercial detector. The planar detector using selfmade germanium single crystal was also successfully manufactured. The research group appeals for speeding up the pace of independent innovation on the high-purity germanium, and achieving the high-purity germanium localization as soon as possible. 相似文献
163.
164.
165.
针对传统云水含量传感器体积大,功耗大等问题,本文基于可调谐半导体激光器吸收光谱技术,研制了一种云水含量检测系统.采用1 368.6nm分布式反馈半导体激光器作为检测光源,设计了基于TLC7528芯片的正交锁相放大器,提高了测量的稳定性和抑制噪声的能力;单板实现了激光器驱动、谐波信号处理、浓度反演功能.系统在不同浓度,不同温度下进行在线检测,实验结果表明,系统响应时间为10s左右,水含量在0~16g/m3范围内误差小于5%,在-55^+60℃条件下可正常工作.该系统体积小,检测精度高,响应速度快,性能不受温度影响,很好地满足了机载云层探测需要. 相似文献
166.
167.
Marek Augustyniak Bolesław Augustyniak Leszek Piotrowski Marek Chmielewski Wojciech Sadowski 《Journal of magnetism and magnetic materials》2006
Experimental results are shown of magneto-acoustic emission (MAE) and Barkhausen effect (BE) for two ferritic steel plates of different dimensions. The paper presents preliminary results of modelling the MAE, based on the finite element method (FEM), taking into account the key role of the eddy currents. Explanations are suggested as to the effects of MAE peak maximum growth, shift, as well as the characteristic BE profiles at the bottom of the large plates. 相似文献
168.
M. Sadowski A. Szydlowski M. Jaskola T. CzyzewskiA. P. Kobzev 《Radiation measurements》1997,28(1-6):207-210
Samples made of the CR-39 and PM-355 plastic nuclear track detectors (NTDs) as well as of the CN films were irradiated with quasi-monoenergetic beams of protons, alphas, N+-, and O+-ions produced by various accelerators. For different samples an energy value of the particle beams was changed from several hundreds keV to 3 or 4.5 MeV. After irradiation the detector samples were etched chemically under controlled conditions during periods lasting from 2 hrs to 20 hrs. Every 2 hrs track diameters were measured by means of an optical microscope. Differences in the crater diameters in the detectors etched in steps, and those etched continously, have been found to be smaller than 10 percent. The paper results detailed calibration diagrams showing a dependence of track diameters on the ion energy value for different etching times. 相似文献
169.
Grzegorz ?ukaszewicz Witold Sadowski 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》2004,15(1):247-257
We investigate the flow of a magneto-micropolar fluid in
an arbitrary unbounded domain on which the Poincaré inequality
holds. Assuming homogeneous boundary conditions and the external
fields to be almost periodic in time we prove the existence of the
uniform attractor by using the energy method [10] which we
generalize to nonautonomous systems. We consider the problem in an
abstract setting that allows to include also other hydrodynamical
models. In particular, we extend the result of R. Rosa [12]
from autonomous to nonautonomous Navier-Stokes equations in
unbounded domains. 相似文献
170.
The stability constantsK
1=3.6 andK
2=1 of Nd(MeOH)
x
NO
3
2+
and Nd(MeOH)
x
(NO3)
2
+
complexes were determined spectrophotometrically. On the basis of an analysis of the stepwise stability constants ratio it was found that these are inner sphere complexes.
Untersuchungen zon Nd-Nitratokomplexen in wäßrig-methanolischen Lösungen
Zusammenfassung Es wurden die StabilitätskonstantenK 1=3.6 undK 2=1 der Komplexe Nd(MeOH) x NO 3 2+ und Nd(MeOH) x (NO3) 2 + spektrophotometrisch bestimmt. Basierend auf einer Analyse der stufenweisen Stabilitätskonstanten wurde festgestellt, daß es sich um Komplexe der inneren Sphäre handelt.相似文献