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1.
Solution and solid-state properties of two new perfluoroalkyl end-substituted analogues of distyryl-bithiophene (CF3-DS2T and diCF3-DS2T) are presented. Vacuum deposited thin films were investigated by atomic force microscopy, X-ray diffraction, and implemented as active layers into organic thin film transistors. While physicochemical measurements in solution suggest a preferential hole injection and transport inside CF3-DS2T and diCF3-DS2T films, electrical measurements performed under high vacuum show that CF3-DS2T behaves as n-type semiconductor while no charge transport was measured in diCF3-DS2T. The results highlighted the importance of substituents on conjugated backbone and on the resulting fine ordering in solid state to control the charge transport.  相似文献   
2.
Let p be an odd prime number, and let Q p be the field of rational p-adic numbers.The aim of this work is the determination of the standard form of an Eisenstein polynomial defining a normal wildly ramified extension of Q p . We prove first the equivalence between normality and cyclicity, give some essential normality conditions for the general case (degree p n ), then we solve the problem completely for the case (degree p 2) also, we obtain that the normality depends on seven congruences modulo p m between the coefficients of the considered polynomial with just m = 2 or 3. Note that the case (degree p) was solved by Öystein Ore (see Math. Annalen 102 (1930), 283–304). Also examples are given.  相似文献   
3.
The study aimed to develop a new glutathione (GSH) oral formulation to enhance the delivery of GSH and counter the nephrotoxicity of the anticancer drug, cyclophosphamide (CP). A nanostructured lipid carrier glutathione formulation (GSH-NLCs) composed of glutathione (500 mg), stearic and oleic acid (300 mg, each), and Tween® 80 (2%, w/v) was prepared through the emulsification-solvent-evaporation technique, which exhibited a 452.4 ± 33.19 nm spheroidal-sized particulate material with narrow particle size distributions, −38.5 ± 1.4 mV zeta potential, and an entrapment efficiency of 79.8 ± 1.9%. The GSH formulation was orally delivered, and biologically tested to ameliorate the CP-induced renal toxicity in a rat model. Detailed renal morphology, before and after the GSH-NLCs administration, including the histopathological examinations, confirmed the ameliorating effects of the prepared glutathione formulation together with its safe oral delivery. CP-induced oxidative stress, superoxide dismutase depletion, elevation of malondialdehyde levels, depletion of Bcl-2 concentration levels, and upregulated NF-KB levels were observed and were controlled within the recommended and near normal/control levels. Additionally, the inflammatory mediator marker, IL-1β, serum levels were marginally normalized by delivery of the GHS-NLCs formulation. Oral administration of the pure glutathione did not exhibit any ameliorating effects on the renal tissues, which suggested that the pure glutathione is reactive and is chemically transformed during the oral delivery, which affected its pharmacological action at the renal site. The protective effects of the GSH-NLCs formulation through its antioxidant and anti-inflammatory effects suggested its prominent role in containing CP-induced renal toxicity and renal tissue damage, together with the possibility of administrating higher doses of the anticancer drug, cyclophosphamide, to achieve higher and effective anticancer action in combination with the GSH-NLCs formulation.  相似文献   
4.
Site‐selective functionalization of C?H bonds in small complex molecules is a long‐standing challenge in organic chemistry. Herein, we report a broadly applicable and site‐selective aromatic C?H dibenzothiophenylation reaction. The conceptual advantage of this transformation is further demonstrated through the two‐step C?H [18F]fluorination of a series of marketed small‐molecule drugs.  相似文献   
5.
This paper is focused on the dynamic formulation of mechanical joints using different approaches that lead to different models with different numbers of degrees of freedom. Some of these formulations allow for capturing the joint deformations using a discrete elastic model while the others are continuum-based and capture joint deformation modes that cannot be captured using the discrete elastic joint models. Specifically, three types of joint formulations are considered in this investigation; the ideal, compliant discrete element, and compliant continuum-based joint models. The ideal joint formulation, which does not allow for deformation degrees of freedom in the case of rigid body or small deformation analysis, requires introducing a set of algebraic constraint equations that can be handled in computational multibody system (MBS) algorithms using two fundamentally different approaches: constrained dynamics approach and penalty method. When the constrained dynamics approach is used, the constraint equations must be satisfied at the position, velocity, and acceleration levels. The penalty method, on the other hand, ensures that the algebraic equations are satisfied at the position level only. In the compliant discrete element joint formulation, no constraint conditions are used; instead the connectivity conditions between bodies are enforced using forces that can be defined in their most general form in MBS algorithms using bushing elements that allow for the definition of general nonlinear forces and moments. The new compliant continuum-based joint formulation, which is based on the finite element (FE) absolute nodal coordinate formulation (ANCF), has several advantages: (1) It captures modes of joint deformations that cannot be captured using the compliant discrete joint models; (2) It leads to linear connectivity conditions, thereby allowing for the elimination of the dependent variables at a preprocessing stage; (3) It leads to a constant inertia matrix in the case of chain like structure; and (4) It automatically captures the deformation of the bodies using distributed inertia and elasticity. The formulations of these three different joint models are compared in order to shed light on the fundamental differences between them. Numerical results of a detailed tracked vehicle model are presented in order to demonstrate the implementation of some of the formulations discussed in this investigation.  相似文献   
6.
7.
Several molecularly imprinted polymers (MIPs) were prepared in the present work, and their binding properties were evaluated in comparison with a nonimprinted polymer (NIP). An optimized MIP was selected and applied for selective extraction and analysis of haloperidol in rabbit brain tissue. A molecularly imprinted solid-phase extraction (MISPE) method was developed for cleanup and preconcentration of haloperidol in brain samples before HPLC-UV analysis. Selectivity of the MISPE procedure was investigated using haloperidol and some structurally different drugs with similar polarity that could exist simultaneously in brain tissue. The extraction and analytical process was calibrated in the range of 0.05–10 ppm. The recovery of haloperidol in this MISPE process was calculated between 79.9 and 90.4 %. The limit of detection (LOD) and the limit of quantification (LOQ) of the assay were 0.008 and 0.05 ppm, respectively. Intraday precision and interday precision values for haloperidol analysis were less than 5.86 and 7.63 %, respectively. The MISPE method could effectively extract and concentrate haloperidol from brain tissue in the presence of clozapine and imipramine. Finally, the imprinted polymer was successfully applied for the determination of haloperidol in a real rabbit brain sample after administration of a toxic dose. Therefore, the proposed MISPE method could be applied in the extraction and preconcentration before HPLC-UV analysis of haloperidol in rabbit brain tissue.  相似文献   
8.
We prove that the Quasi Differential of Bayoumi of maps between locally bounded F-spaces may not be Fréchet-Differential and vice versa. So a new concept has been discovered with rich applications (see [1–6]). Our F-spaces here are not necessarily locally convex  相似文献   
9.
Site-selective functionalization of C−H bonds in small complex molecules is a long-standing challenge in organic chemistry. Herein, we report a broadly applicable and site-selective aromatic C−H dibenzothiophenylation reaction. The conceptual advantage of this transformation is further demonstrated through the two-step C−H [18F]fluorination of a series of marketed small-molecule drugs.  相似文献   
10.
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