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191.
采用APPLEⅡ微机控制9W测微光密度计,实现对谱板自动化测量。论述了该系统的工作原理、主要功能和特性。给出了使用该系统所测得的实际光谱谱图。  相似文献   
192.
We consider different definitions of the correlation dimension and find some relationships between them and other characteristics of dimension type such as Hausdorff dimension, box dimension, etc. We also introduce different ways to define and study the generalized spectrum for dimensions—a one-parameter family of characteristics of dimension type.  相似文献   
193.
The spectral and luminescence characteristics of water and water–ethanol solutions of dyes have been investigated. The efficiency of the process of association of dye molecules and the structure of the complexes formed depending on their concentration and the solvent composition have been established. The presence of inhomogeneities in the distribution of dissolved complex molecules in the water matrix which determine the high efficiency of the association processes in water solutions as compared with other solvents is shown. The characteristic sizes of these inhomogeneities have been estimated.  相似文献   
194.
The potassium lithium niobate crystals have been grown up. The shapes of solid-melt interfaces which maintaining the steady growth of the potassium lithium niobate crystals have been described. The optical transmission spectrum of the crystal has been surveyed. The perfected crystals showed good Second Harmonic Generation properties.  相似文献   
195.
在“星光Ⅱ”激光装置上对Mg/Al混合材料埋点靶进行三倍频激光打靶实验,用空间分辨晶体谱仪测量靶材料发射的X光光谱,获取了示踪离子谱线实验数据。采用多组态Dirac-Fock方法计算所需原子参数,并在局域热动平衡条件下建立了双示踪离子谱线强度比随电子温度的变化关系。在此基础上由双示踪元素等电子谱线法确定了Mg/Al混合材料埋点靶激光等离子体电子温度空间分布。  相似文献   
196.
Nanozymes can be used as favorable substitutes for natural enzymes because of their strong catalytic activity and good stability. At the same time, research on single-atom catalysts (SACs) with isolated metal atoms as active centers is also in full swing, showing excellent performance in a variety of catalytic reactions. With the in-depth study of SACs, people have a comprehensive understanding of them and put forward the concept of single-atom nanozymes (SAzymes) by combining nanozymes with SACs. As a new type of nanomaterial, SAzymes have attracted great interest due to their remarkable catalytic activity and rapid energy conversion. However, most applications of SAzymes are mainly in the fields of biomedicine and biosensing, and less research has been done in the field of the environment. Based on the amazing ability of nanozymes to detect and degrade pollutants, SAzymes are also used in the environmental field, and even they will show better capabilities. This review mainly analyses common transition metal-based SAzymes and describes their applications in the field of environmental pollutants.  相似文献   
197.
In this paper, an ultra-wideband Janus metastructure (MS) utilizing anapole mode for detector in the terahertz (THz) range by graphene is proposed. Specifically, when Fermi level (Ef) is set to 0.9 eV, the MS demonstrates ultra-broadband absorption exceeding 0.9 from 0.754 to 5 THz in the −z-direction with a relative bandwidth of 147.6 %, in which perfect absorption of over 98% develops from 3.24 to 5 THz. In the case of the +z-direction, the absorptivity maintains around 0.6 within the 0.745 ∼ 5 THz range. As Ef equals 0 eV, the difference in absorption between the −z-direction and +z-direction exceeds 0.9 from 4.49 to 4.76 THz. The study also explores the MS for refractive index sensing near 3.71 THz by a unique difference detection, measuring two refractive index ranges: 1.2 ∼ 2.6 and 4.5 ∼ 4.7, with corresponding sensitivities of 0.0450 and 0.0304, respectively. Owing to its highly symmetrical structure, the MS is insensitive to the polarization state of the electromagnetic (EM) waves, performing remarkable angular stability as the incident angle varies from 0 to 60 degrees in the −z-direction. These splendid properties make the design a good candidate for biomedical sensing, EM cloaking, and full-space EM wave control.  相似文献   
198.
在欧姆加热和低混杂波电流驱动条件下,利用磺化汞半导体探测器和碘化钠和探测器测出了HL-1M装置的X射线能谱,研究了器壁硅化前后电子速率分布和电子温度变化的特点,给出了X射线辐射强度与LHCD能量沉积的关系。  相似文献   
199.
拉曼光谱在宝玉石鉴定中的应用   总被引:3,自引:1,他引:3  
:利用拉曼光谱鉴定宝石越来越受到宝石学界的关注。本文测定了许多宝石的拉曼光谱 ,其中包括宝石、玉石、人造宝石和一些贵重宝石的代用品。这些谱图可以作为宝石鉴定的标准对照谱。文中还讨论了宝石拉曼光谱鉴定的一些特点  相似文献   
200.
The distinctive features of the atomic and electronic structure of thin surface layers of substances in the process of formation of epitaxial silicon films on silicon are studied using the procedures of reflection and scattering of ultrasoft x-ray radiation. The angular distribution of the scattered x-ray radiation (the scattering indicatrices) and the near fine structure of SiL2,3 spectra of reflection are investigated. The assumption of the sensitivity of the observed peak of anomalous scattering (the Yoneda peak) of x-ray radiation to the presence, in the surface regions of the materials, of extended double-boundary defects, the defects of packing, grain boundaries, dislocations, etc. is made. It is shown that the experimental procedure used makes it possible to obtain information on the surface layers of substances. Translated from Zhurnal Priklaldnoi Spektroskopii, Vol. 67, No. 4, pp. 496–498, July–August, 2000.  相似文献   
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