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1.
The main properties of the first- and second-order moments of polarized hydrogen lines, forming in the presence of stationary electric and magnetic fields, are reviewed. The analytical results presented here apply directly to the case of optically-thin emission lines in the LTE regime. Some applications of such results to electric- and magnetic-field diagnostics in (solar) plasmas are then briefly considered.On leave from the Dipartimento di Astronomia e Scienza dello Spazio, Università di Firenze, Largo E. Fermi 5, I-50125 Firenze, Italy  相似文献   
2.
张开莲  郑学娟 《矿物岩石》1990,10(1):110-113
本法采用氯酸钾-王水分解样品,选用硝酸镍作基体改进剂,提高了灰化温度。使用石墨杯原子化器,Zeeman效应扣除背景,实现了用石墨炉原子吸收法直接测定硅酸盐中微量砷。快速、简便,其绝对灵敏度达5.7×10~(-11)(g/l%),变动系数小于8%。  相似文献   
3.
铷原子频标中微波功率频移的研究及其控制方法   总被引:1,自引:0,他引:1  
针对铷原子频标中微波功率频移的传统解释与实验现象不相符合的矛盾,曾提出以ACZeeman效应为核心的新解释.本文以实验检验了该解释,尤其是ACZeeman效应频移公式的正确性,实验结果与理论相符合;最后探讨了控制微波功率频移的方法。  相似文献   
4.
Magnetic field strengths and directions can be estimated using many different observational techniques that span a wide range of wavelengths. Each observational method favours different regimes of scale size, density and other physical conditions. The available techniques and their ranges of applicability are briefly described and the current status of observations is reviewed, with particular emphasis on high-resolution observations of star-forming regions.  相似文献   
5.
Observations of AGNs and microquasars by ASCA, RXTE, Chandra and XMM-Newton indicate the existence of broad X-ray emission lines of ionized heavy elements in their spectra. Such spectral lines were discovered also in X-ray spectra of neutron stars and X-ray afterglows of GRBs. Recently, Zakharov et al. [MNRAS 342 (2003) 1325] described a procedure to estimate an upper limit of the magnetic fields in regions from which X-ray photons are emitted. The authors simulated typical profiles of the iron Kα line in the presence of magnetic field and compared them with observational data in the framework of the widely accepted accretion disk model. Here we further consider typical Zeeman splitting in the framework of a model of non-flat accretion flows, which is a generalization of previous consideration into non-equatorial plane motion of particles emitting X-ray photons. Using perspective facilities of space borne instruments (e.g., Constellation-X mission) a better resolution of the blue peak structure of iron Kα line will allow to evaluate the magnetic fields with higher accuracy.  相似文献   
6.
对塞曼效应石墨炉原子吸收法对地质样中痕量银的测定进行了研究。简化了样品处理过程。对地质标样及实际样品分析获得了满意的结果加标回收率为96.2%-103.5%,相对标准偏差为3.04%-4.77%所采用的方法快速、简便,准确。  相似文献   
7.
本文根据偏振辐射转移方程组就形成于有磁场的恒星大气中的Stokes轮廓的一些特征量与磁场强度大小的关系从理论上进行了探讨。结果表明:在强场情形下,L,Q,U,V的绝对值在非常靠近Zeeman分裂量±Δλ_H处达到极大;Hale的测量方法给出了总的场强的很好量度。最后用合成轮廓作出了相应的检验。  相似文献   
8.
Summary The Sun provides us with a unique astrophysics laboratory for exploring the fundamental processes of interaction between a turbulent, gravitationally stratified plasma and magnetic fields. Although the magnetic structures and their evolution can be observed in considerable detail through the use of the Zeeman effect in photospheric spectral lines, a major obstacle has been that all magnetic structures on the Sun, excluding sunspots, are smaller than what can be resolved by present-day instruments. This has led to the development of indirect, spectral techniques (combinations of two or more polarized spectral lines), which overcome the resolution obstacle and have revealed unexpected properties of the small-scale magnetic structures. Indirect empirical and theoretical estimates of the sizes of the flux elements indicate that they may be within reach of planned new telescopes, and that we are on the verge of a unified understanding of the diverse phenomena of solar and stellar activity.In the present review we describe the observational properties of the smallscale field structures (while indicating the diagnostic methods used), and relate these properties to the theoretical concepts of formation, equilibrium structure, and origin of the surface magnetic flux.On leave from Institute of Astronomy, ETH-Zentrum, CH-8092 Zürich, SwitzerlandThe National Center for Atmospheric Research is sponsored by the National Science Foundation  相似文献   
9.
XG-7Z塞曼测汞仪介绍及痕量汞的分析方法   总被引:1,自引:0,他引:1  
汞蒸气及其化合物在地质构造、金属矿床、污染源及古墓和古遗址等处相对富集形成汞气晕,利用汞的特性,进行汞量测量,开展地质构造、矿产勘查、污染源的圈定等方面的研究,使其在工农业生产中得到更广泛的应用。笔者对方法、仪器原理进行简单的介绍,并详细讨论各种样品中痕量微量汞含量测试方法及应用效果。针对汞分析前处理操作繁琐、重现性差的问题,提出了直接测汞法测定固体粉末样品中汞,该法样品无须进行处理,含汞废气经吸收剂无害化处理后排放。分析速度快,准确度高,且不需任何化学试剂,对人体无伤害。  相似文献   
10.
塞曼原子吸收法测定多金属结核中高含量铁锰的研究   总被引:2,自引:0,他引:2  
利用日立偏振塞曼原子吸收分光光度计更换低灵敏度共振吸收线的方法,研究高含量Fe、Mn测定的最佳工作条件,在一份溶液中测定大洋多金属结核中Fe和Mn。对于wB在1% ̄36%的Fe和Mn分析的相对标准偏差(n=10)分别为0.6% ̄1.0%和0.7% ̄1.1%。经国家标准样品分析验证,方法可靠,与不同分析方法对比,结果满意。方法用于新研制的多金属结核中Fe、Mn定值分析,结果与初定值基本符合。  相似文献   
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