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1.
火花—AES法测定中低合金钢中14种少量元素   总被引:1,自引:0,他引:1  
本文所叙述的方法是将固体中低合金钢样品在车床或铣床上打平。或在磨片机上磨成理想的平面。然后用选好的最佳仪器测量条件,用铁元素做内标,按照自编的分析程序在多基体火花发射台的氩气氢气中激发,进行火花原子发射光谱法测定。此法简便,快速,所得分析结果与推荐的标准值基本一致,其相对标准偏差RSD≤10%,测试结果令人满意。  相似文献   

2.
本文所叙述的方法是将固体钢铁样品在车床、铣床上打平,或在磨片机上磨成平面。然后用选好的最佳仪器测量条件,用铁元素做内标,按照自编的分析程序在MBS火花发射台的氩气气氛中激发,进行火花原子发射光谱法测定。此法简单、快速,所得分析结果与推荐的标准值基本一致,其相对标准偏差RSD≤10%,测试结果令人满意。  相似文献   

3.
本文叙述的方法是将固体铝合金样品在车床或铣床上加工成平面,然后以选好的仪器测量条件,用铝元素做内标,按照自编分析程序在MBS火花台上氩气气氛中激发,进行火花-原子发射光谱法测定。此方法快速、简便,标准样品所得分析结果基本与标称值吻合,3次测定结果相对偏差≤20%。在重复性实验中,不同时间内测定同一样品10次,10个被测元素结果的相对标准偏差RSD≤10%。  相似文献   

4.
本文所叙述的方法是将固体工业纯铁在车床或铣床上打平,然后以选好的仪器测量条件,用铁元素作内标,按照自编分析程序在MBS火花发射台的氩气气氛中激发,进行火花原子发射光谱法测定,此法快速、简便,所得分析结果基本与标准值相同,其相对标准偏差RSD≤10%,结果令人满意。  相似文献   

5.
火花发射光谱分析钢中单一夹杂物的研究已有文献报导,但用火花光谱分析钢中复合夹杂物一直是个难题.钢中复合夹杂物是一种单一夹杂物包裹另外一种单一夹杂物组成的复合体,或由两个及以上单一夹杂物紧密相邻结合体.如何区分材料中同时存在但不相邻的两种单一夹杂物和二者复合夹杂物,用火花发射光谱技术难于实现.该工作采用火花光谱原位统计分...  相似文献   

6.
伪火花放电开关的陶瓷表面放电触发研究   总被引:6,自引:4,他引:2       下载免费PDF全文
 设计了伪火花开关的陶瓷材料表面放电触发器,该触发器体积小,结构简单,可焙烧。经大量实验表明,较传统的表面放电触发器可靠性提高,寿命延长,用它触发的伪火花开关(放电电压30~2kV)具有稳定的放电时延(50~340ns)和时延抖动(15~40ns)。由于触发电流大,因此可在极低的开关电压下触发开关,对耐受电压30kV的伪火花开关,其最低可触发开关电压可至600V。  相似文献   

7.
采用固体径迹火花自动计数器测量弱中子场下狭小空间内的中子。固体径迹火花自动计数器用贫化铀和浓缩铀电镀片作为转换靶,采用电镀法制备浓缩铀镀片和贫化铀镀片。  相似文献   

8.
本文介绍利用溶液法和粉末法进行合金钢光谱分析的方法,以克服制备标准样品的困难和消除样品组织结构和物理状态的影响。将钢样溶解于酸制成的溶液,滴在平头碳电极上用火花激发,或将钢样制成氧化物粉末,填于碳孔中,用交流电弧激发。初步结果指出,这些方法可以满足一般分析要求。  相似文献   

9.
 在赝火花放电过程中观察到异常加速的高能粒子,利用分析磁铁证实了这一物理现象。对照超快激光打靶产生的数百MeV量级的脉冲离子束,以及类星体涡旋结构产生超高能准直宇宙射线等现象,作者提出用涡旋动力学产生的挠场轴向加速来解释这些发生在不同物质运动层次的异常加速现象。阐述了集体场或尾场加速理论在解释这种理论时的不足之处。  相似文献   

10.
火花熔蚀-电感耦合等离子体光谱法(SA-ICP)用于测量锆石中铪-锆比值和锰铁矿瘤中的铈、钴、铁、铅、镍和磷。用信背比和信噪比的序贯单纯形优化法建立了用于高压火花和氩气ICP系统的六个操作参数。将磨细的样品与铜压成饼,并从样品中熔蚀出的分析物和基体元素的原子发射信号的时间相关性给出一种用火花来作选择取样的方法。测量锆石中的铪、锆浓度比的精密度为4%(相对标准偏差)。对于锰铁矿瘤,根据分析线对锰(Ⅱ)257.610纳米线强度比的光谱测定结果达到分析精密度范围为7-14%(相标准偏差)。分析的准确度用参比物USGS诺得(Nod)P-1的标准物加入法来决定,而与锰浓度的测量无关。  相似文献   

11.
几种超弹性多次碰撞的讨论   总被引:1,自引:0,他引:1  
本文分析了几种超弹性碰撞多次连续碰撞的过程,以期对照弹性碰撞的进一步理解.实现这些物理过程对物理教学是相当有趣的.  相似文献   

12.
WU Ning   《理论物理通讯》2007,48(9):469-472
In general relativity, the equation of motion of the spin is given by the equation of parallel transport, which is a result of the space-time geometry. Any result of the space-time geometry cannot be directly applied to gauge theory of gravity. In gauge theory of gravity, based on the viewpoint of the coupling between the spin and gravitational field,an equation of motion of the spin is deduced. In the post Newtonian approximation, it is proved that this equation gives the same result as that of the equation of parallel transport. So, in the post Newtonian approximation, gauge theory of gravity gives out the same prediction on the precession of orbiting gyroscope as that of general relativity.  相似文献   

13.
夏上达 《发光学报》2007,28(4):465-478
简述了近20多年以来我们在稀土发光和光谱理论方面所做的主要工作、取得的进展和成果。包括:(1)关于(4f)N组态内单光子跃迁强度:推广Judd-Ofelt三参量公式,在其中计入"J混合"(偶宇称晶场成分造成的)导致的修正;澄清了国际上关于Judd-Ofelt全参量公式中"静力学项"和"动力学项"相对正负号的争论(仍为负号)。(2)关于(4f)N组态内双光子过程强度:提出直接计算强度方法(放弃缔合近似,利用Ce3+的5d和左邻RE3+的(4f)N能级-波函资料,近似模拟出最重要的虚中间组态(4f)N-15d的能级-波函结构)来讨论和改进Judd-Ofelt缔合近似。(3)固体中声子辅助的稀土离子间能量传输理论:发现HLO理论关于单声子过程中的"干涉相消"实际只适合于对角过程,而非对角过程则是"干涉相加",因而,后者首要的是单声子而非双声子过程;同时,用"晶体格波模"取代"Debye模"描述能量传输中的声子,给出了新模型下计算对角和非对角过程速率等物理量的整套公式。并由之看出:波矢q=0和对应色散曲线扁平段的光学声子对单声子非对角过程速率有完全不能忽略的贡献,这些都不同于或超出于HLO理论。(4)提出和发展了分析指认4f-5d跃迁光谱的简单理论模型,用能量和跃迁强度同时进行近似拟合,成功地分析指认了从(4f)3到(4f)13离子在几种基质中的4f→5d吸收(激发)谱,也成功用于若干5d→4f辐射谱。(5)对跃迁的初末晶场态同时引用有效自旋哈密顿描述稀土离子间超交换作用,成功地解释了低温10 K时立方结构的纯稀土冰晶石晶体Cs2NaLnCl6(Ln=Er,Yb)等的吸收谱中0声子线(量级为几个cm-1)的精细分裂。  相似文献   

14.
迈克尔逊干涉仪实验中的三个问题   总被引:5,自引:0,他引:5  
郭立群  赵英 《大学物理实验》2002,15(2):40-41,45
本文对在大学物理实验迈克尔逊干涉仪调节和使用题目中被教师忽略却常被学生提出的三个问题进行了细致分析和讨论,并给出了解决建议。  相似文献   

15.
The luminescence spectra of AgCl microcrystals were measured in two different regimes: in the regime of excitation of stationary luminescence and in the regime of photostimulated burst of luminescence. Differences between the spectra of stationary luminescence and the spectra of photostimulated-luminescence burst in the range between 430 and 590 nm have been found. The luminescence spectra are complex; the ratio of intensities for elementary components changes with the technique of excitation. Differences in the form and composition of complex luminescence bands obtained under different conditions of registration are attributed to the recombination interaction of the luminescence centers. It is shown that analysis of the dependences of intensity ratios for the elementary components of a complex luminescence band on the exciting-radiation intensity allows one to evaluate the mechanism of recombination in elementary bands provided that the mechanism is known for at least one luminescence band.__________Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 72, No. 1, pp. 85–89. January–February, 2005.  相似文献   

16.
Astronomers have two approaches to trying to determine the age of the Universe. They can estimate the ages of individual objects in the Universe and specifically in our Galaxy. These estimates use either the observed properties of stars and theoretical ideas concerning stellar evolution or the abundances of long-lived radioactive isotopes and their decay products. Alternatively they can use cosmological theories and observations to try to determine the age of the entire Universe. Obviously the Universe must be older than its component parts but neither of the above methods is sufficiently reliable that this is true of the deduced ages. As a result, it is from time to time reported that some object in the Universe is older than the Universe itself. In this article we discuss the methods that are currently being used to determine the age and we emphasize the problems in obtaining reliable results. It is not at present possible to provide a definite value for the age of the Universe.  相似文献   

17.
对理论力学教材中角动量定理的各种不同表达式进行了归纳、比较、讨论、明确了它们之间的区别、联系及其适用条件。  相似文献   

18.
H. Dandache 《Il Nuovo Cimento D》1989,11(10):1501-1506
Summary The semi-empirical Hugoniot equation of state is obtained by using the third-order tangency between the isentropic and the Hugoniot curves at the origin of coordinates. The results of this model are in good agreement with Carter’s experimental data for fourteen elements from the lanthanides series in the lower phase only. Due to postal troubles with Lebanon, it was impossible to send proffs to the author as he requested.  相似文献   

19.
 利用计算机高级语言提供的伪随机数发生器,通过“高斯筛选”和“求平均值”两种方法,开发出满足正态分布的随机数发生器。将其应用于分析大型激光装置光路稳定性的模拟软件中,成功地完成了对“神光Ⅲ原型装置四程放大器”的光路稳定性分析。  相似文献   

20.
WU Ning 《理论物理通讯》2007,48(3):469-472
In general relativity, the equation of motion of the spin is given by the equation of parallel transport, which is a result of the space-time geometry. Any result of the space-time geometry cannog be directly applied to gauge theory of gravity. In gauge theory of gravity, based on the viewpoint of the coupling between the spin and gravitational field, an equation of motlon of the spin is deduced. In the post Newtonian approximation, it is proved that this equation gives the same result as that of the equation of parallel transport. So, in the post Newtonian approximation, gauge theory of gravity gives out the same prediction on the precession of orbiting gyroscope as that of general relativity.  相似文献   

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