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61.
A general technique for inverting spectral line profiles to obtain physical information about a semi-infinite plasma is described. The technique allows for distinct line and continuum source functions, the presence of both stochastic and systematic velocity fields, and permits all spectral lines in a multiplet to be inverted simultaneously. 相似文献
62.
Lauri J. Missio Hugo S. Braibante Mara E. F. Braibante 《Journal of heterocyclic chemistry》1996,33(4):1243-1245
The reactivity of the enamino compounds 4-amino-3-phenylamino(thio)carbonyl-3-penten-2-one 1 and 2 and ethyl 3-amino-2-phenylamino(thio)carbonyl-2-butyrate 7 and 8 was studied using the reaction with hydrazine hydrate and hydrazine hydrochloride to evaluate the 1,3 electrophilic center of the compounds by the formation of the pyrazole rings. The pyrazoles 3, 4, 5, 9, 11 and 13 were obtained depending on the reaction conditions employed. 相似文献
63.
Horacio Grinberg Julio Marañon Hector Vucetich 《Zeitschrift fur Physik C Particles and Fields》1983,20(2):147-149
The Kustaanheimo-Stiefel transformation as applied to the nonrelativistic hydrogen atom provides one of the rare examples of a free particle moving on a four-dimensional homogeneous space. 相似文献
64.
In the United States, researchers argue that proof is largely concentrated in the domain of high school geometry, thus providing students a distorted image of what proof entails, which is at odds with the central role that proof plays in mathematics. Despite the centrality of proof, there is a lack of studies addressing how to integrate proof into other mathematical domains. In this article, we discuss a teaching experiment designed to integrate algebra and proof in the high school curriculum. Algebraic proof was envisioned as the vehicle that would provide high school students the opportunity to learn not only about proof in a context other than geometry but also about aspects of algebra. Results from the experiment indicate that students meaningfully learned about aspects of both algebra and proof in that they produced algebraic proofs involving multiple variables and a single parameter, based on conjectures they themselves generated. 相似文献
65.
The variations in the chemical compositions of the metallic glasses reported in the literature, as well as the overall lack of experimental data concerning the inhomogeneous deformation behaviour of metallic glass, make the evaluation of the effects of shear band/fracture behaviour on the mechanical properties of metallic glasses difficult. Isolating the effect of local shear band formation on bulk inhomogeneous flow would appear to be a first step in approaching this problem. The mechanical behaviour of Vitreloy metallic glass at room temperature and at various strain rates in tension and compression was investigated. The formation of multiple shear bands was observed at high strain rates. An increase in strain rate leads to enhanced ductility in tension and compression. Some aspects of the deformation processes in tension and compression are discussed. 相似文献
66.
67.
Dr. Mara Beltrán-Gastélum Dr. Berta Esteban-Fernández de Ávila Dr. Hua Gong Dr. Pooyath Lekshmy Venugopalan Prof. Dr. Tibor Hianik Prof. Dr. Joseph Wang Veronika Subjakova 《Chemphyschem》2019,20(23):3177-3180
Herein, we report ultrasound-propelled graphene-oxide coated gold nanowire motors, functionalized with fluorescein-labeled DNA aptamers (FAM-AIB1-apt), for qualitative detection of overexpressed AIB1 oncoproteins in MCF-7 breast cancer cells. The movement of nanomotors under the ultrasound field facilitated intracellular uptake and resulted in a faster aptamer binding with the target protein and thus faster fluorescence recovery. The propulsion behavior of the aptamer functionalized nanomotors greatly enhanced the fluorescence intensity compared to static conditions. The new aptamer@nanomotor-based strategy offers considerable potential for further development of sensing methodologies towards diagnosis of breast cancer. 相似文献
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69.
Altıntas Yemliha Öztürk Esra Aksöz Sezen Keşlioğlu Kâzım Maraşlı Necmettin 《Journal of Thermal Analysis and Calorimetry》2015,122(1):65-72
Journal of Thermal Analysis and Calorimetry - The equilibrated grain boundary groove shapes for solid Bi (Bi–2.87 at.%Ag) in equilibrium with Bi–Ag eutectic liquid have been... 相似文献
70.