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Water Resources Management - The original version of this article unfortunately contains mistake introduced during the publishing process. The author name “M. Fayzul” should be deleted...  相似文献   
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The growth and metastasis of solid tumors is dependent on angiogenesis. The vascular endothelial growth factor (VEGF) and its cell surface receptor in human KDR (kinase domain containing receptor or VEGFR-2) have particular interest because of their importance in angiogenesis. The development of novel inhibitors of VEGFR-2 would be helpful to check the growth of tumors. Quantitative structure activity relationship (QSAR) analyses used to understand the structural factors affecting inhibitory potency of thiazole-substituted pyrazolone derivatives. Several pharmacophore-based models indicated the importance of steric, hydrophobic and hydrogen bond acceptor groups to inhibitory activity. The comparative molecular field analyses (CoMFA) and comparative molecular similarity indices analyses (CoMSIA) based 3D-QSAR models were derived using pharmacophore-based alignment. Both CoMFA (q2 = 0.70, r2 = 0.97 and ) and CoMSIA (q2 = 0.54, r2 = 0.82 and ) gave reasonable results. The molecular docking (receptor-guided technique) with a recently reported receptor structure (PDB = 1YWN) were performed. The docked alignment was subsequently used for 3D-QSAR (CoMFA; q2 = 0.56, r2 = 0.97, , CoMSIA; q2 = 0.58 r2 = 0.91, ). The overall both studies were indicated, steric, electrostatic and hydrogen bond acceptor effects contribute to the inhibitory activity. CoMFA and CoMSIA models suggested that a positive bulk with hydrophobic effect is desirable around position 4 and 5 and hydrogen bond acceptor groups around pyrazolones ring will be helpful.  相似文献   
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The study compared diagnostic potential of magnetocardiography (MCG), electrocardiography (ECG) and echocardiography (echo-CG) in 18 patients with arterial hypertension (AH). 32 healthy males served as control. Elements of MCG from normal subjects have been analyzed morphologically in 36 points of precordial leads. Left ventricular hypertrophy was registered at echo-CG, MCG, ECG in 11 (61%), 16 (84%) and 7 (34%) of the AH patients, respectively. Left atrial hypertrophy was discovered primarily by echo-CG and MCG. Defects in ventricular repolarization were recorded by MCg in 7 (39%) patients basing on MCG, echo-CG and rarely ECG signs of left ventricular hypertrophy. MCG is recommended as an effective tool in diagnosis of "hypertensive heart".  相似文献   
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Chemistry and Technology of Fuels and Oils - The sorption properties of native and modified petroleum asphaltenes with respect to phenol were studied under static conditions. The asphaltenes were...  相似文献   
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Rigorous non-linear models of elasto-plastic contact deformation are time-consuming in numerical calculations for the distinct element method (DEM) and quite often unnecessary to represent the actual contact deformation of common particulate systems. In this work a simple linear elasto-plastic and adhesive contact model for spherical particles is proposed. Plastic deformation of contacts during loading and elastic unloading, accompanied by adhesion are considered, for which the pull-off force increases with plastic deformation. Considering the collision of a spherical cohesive body with a rigid flat target, the critical sticking velocity and coefficient of restitution in the proposed model are found to be very similar to those of Thornton and Ning’s model. Sensitivity analyses of the model parameters such as plastic, elastic, plastic-adhesive stiffnesses and pull-off force on work of compaction are carried out. It is found that by increasing the ratio of elastic to plastic stiffness, the plastic component of the total work increases and the elastic component decreases. By increasing the interface energy, the plastic work increases, but the elastic work does not change. The model can be used to efficiently represent the force-displacement of a wide range of particles, thus enabling fast numerical simulations of particle assemblies by the DEM.  相似文献   
8.
Reactions between aqueous solutions of aluminum salts and ammonium terephthalate at pH 6–8 lead to the formation of a previously unknown, weakly ordered phase. It has signs of a layered compound with a unit cell parameter of 1.072–1.073 nm. Its empirical composition can be represented by the formula Al2O3 · xC8H6O4 · yH2O · δ(NH3), where x = 0.7–1.2, y = 4.4–6.0, and δ = 0–0.4. It has good structural order across the layers, whereas the order along the layers is weaker and depends on synthesis conditions. Calcination at 120°C leads to partial dehydration and changes the order along the layers, whereas the order across the layers changes little, with a slight increase in lattice strain. Heat treatment at 400°C leads to almost complete dehydration and fully eliminates the order along the layers, whereas the order across the layers is partially retained. Firing at 800°C leads to the formation of γ-Al2O3. A structural model has been proposed for the new phase.  相似文献   
9.
Novel flexible dielectric composites composed of polyvinyl alcohol (PVA), polyethylene glycol (PEG), and graphene oxide (GO) with high dielectric constant and low dielectric loss have been developed using facile and eco-friendly colloidal processing technique. The structure and morphology of the PVA/PEG/GO composites were evaluated using Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, UV-vis spectroscopy (UV-vis), X-ray diffraction (XRD), scanning electron microscopy (SEM), and atomic force microscopy (AFM). The dielectric behavior of PVA/PEG/GO composites was investigated in the wide range of frequencies from 50 Hz to 20 MHz and temperature in the range 40 to 150 °C using impedance spectroscopy. The dielectric constant for PVA and PVA/PEG (50/50) blend film was found to be 10.71 (50 Hz, 150 °C) and 31.22 (50 Hz, 150 °C), respectively. The dielectric constant for PVA/PEG/GO composite with 3 wt% GO was found to be 644.39 (50 Hz, 150 °C) which is 60 times greater than the dielectric constant of PVA and 20 times greater than the dielectric constant of PVA/PEG (50/50) blend film. The PVA/PEG/GO composites not only show high dielectric constant but also show low dielectric loss which is highly attractive for practical applications. These findings underline the possibilities of using PVA/PEG/GO composites as a flexible dielectric material for high-performance energy storage applications such as embedded capacitors.  相似文献   
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ABSTRACT

Polyvinylchloride (PVC)/nickel oxide (NiO)/tungsten oxide (WO3) nanocomposite films were prepared via solution casting technique. The crystallinity, morphology, and the analysis of dispersion state of PVC/NiO/WO3 nanocomposite was carried out using X-ray diffraction (XRD) and scanning electron microscopy (SEM). The dielectric studies of nanocomposite films were investigated and a maximum dielectric constant of 2.3 with dielectric loss (tan δ) of 2.4 was attained. The EMI shielding studies were carried out in the X and Ku-band frequency range (8 GHz-18 GHz). The maximum SE of 15.78 dB in X-band and 12.05 dB in Ku-band was achieved for 75/20/5 compositions of the PVC/NiO/WO3 nanocomposite.  相似文献   
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