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231.
Seven mixed-ligand complexes of cobalt(II), nickel(II) and copper(II) containing benzoylacetone andL-proline (HL1), 2-pyrrolidone-5-carboxylic acid (HL2) orL-thioproline (HL3) were prepared and characterized by means of elemental analysis, IR, electronic spectra, magnetic moment measurements and molar conductance. Both HL1 and HL2 coordinate with these metal ions in a neutral zwitterionic form (-NH2-CH-COO), whereas HL3 coordinates as a monobasic chelating agent (O/N). The continuous thermochromism of the nickel(II) complex of HL1 (2) was attributed to a geometry change; it was investigated by DTA, TG, electronic spectra and X-ray powder diffraction techniques.  相似文献   
232.
International Journal of Theoretical Physics - Recently, the Mth coherent state (Mth CS) has been defined to be the resultant state of applying the number operator M times on the coherent state...  相似文献   
233.
Journal of Russian Laser Research - We propose a MXene Ti3C2Tx thin-film and demonstrate as saturable absorber (SA) to generate mode-locked laser pulses. In constructing the SA, titanium carbide...  相似文献   
234.
Fluorinated smectic liquid crystals each with a biphenyl benzoate rigid core are investigated. Molecular structures of the studied compounds have difference only in fluorine position and the length of the carbon chain. Dielectric relaxation study and electro-optical measurements are carried out with the classical SSFLC geometry. The field-induced phase transitions are studied and the(E,T) phase diagram is established.  相似文献   
235.
Miniature optical fiber sensors with thin films as sensitive elements could open new fields for optical fiber sensor applications. Thin films work as sensitive elements and a transducer to get response and feedback from environments, in which optical fibers act as a signal carrier. A novel Ag coated intensity modulated optical fiber sensor based on refractive index changes using IR and UV-Vis(UV-visible) light sources is proposed. The sensor with an IR light source has higher sensitivity compared to a UV-Vis source. When the refractive index is enhanced to 1.38, the normalized intensity of IR and UV-Vis light diminishes to 0.2 and 0.8, respectively.  相似文献   
236.

In this article, we propose a new kind of quantum states based on acting the number operator M times \( {\hat{n}}^M \) on the coherent state. We term this state the Mth coherent state, based on the value of the power M. We find that it is strongly similar to the coherent state as the analysis of the photonic statistical distributions and the overlap with the coherent state illustrate. Also, we find that it asymptotically reaches the minimum uncertainty and has a localized behavior in the Husimi function. However, in contrast to coherent state, the Mth coherent state has strong nonclassical features such as antibunching and squeezing for a relatively long range. Other parameters and measurements are discussed and studied. Finally, we highlight the similarity between the higher orders of the near coherent states and the Mth coherent states in order to potentially generate our proposed state.

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238.
Coumarins are the phytochemicals, which belong to the family of benzopyrone, that display interesting pharmacological properties. Several natural, synthetic and semisynthetic coumarin derivatives have been discovered in decades for their applicability as lead structures as drugs. Coumarin based conjugates have been described as potential AChE, BuChE, MAO and β-amyloid inhibitors. Therefore, the objective of this review is to focus on the construction of these pharmacologically important coumarin analogues with anti-Alzheimer’s activities, highlight their docking studies and structure–activity relationships based on their substitution pattern with respect to the selected positions on the chromen ring by emphasising on the research reports conducted in between year 1968 to 2017.
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240.
For a ring extension is called a universally catenarian pair if every domain , is universally catenarian. When R is a field it is shown that the only universally catenarian pairs are those satisfying . For several satisfactory results are given. The second purpose of this paper is to study going-down pairs (Definition 5.1). We characterize these pairs of rings and we establish a relationship between universally catenarian, going-down and residually algebraic pairs. Received: 1 July 1999; in final form: 5 June 2000 / Published online: 17 May 2001  相似文献   
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