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1.
With the increase of industrialization and urbanization, humankind faces massive oil-based pollution due to tanker accidents, human error, and natural disasters. For this, hydrophobic sorbents are fabricated and their applications for the removal of oil from polluted water sources are investigated. These hydrophobic sorbents are prepared by the condensation reaction of poly(dimethylsiloxane) and tris[3-(trimethoxysilyl)propyl]isocyanurate cross-linker via bulk polymerization. The obtained sorbents exhibit high oil sorption capacity, fast absorption–desorption kinetics, and great reusability. Moreover, they can selectively absorb oil from the water surface, thus making them practical for water clean-up applications.  相似文献   
2.
The nave of Santa Maria Novella, a Dominican church in Florence Italy is representative of a Florentine Gothic system of construction. This system, consisting of domical rib vaults on square nave bays, high side aisles, and crypto-buttressing, differs substantially from the French high Gothic system of even-level-crown rib vaults on rectangular bays, with flying buttresses over relatively low aisles. An investigation into the structural aspects of the Florentine Gothic construction system reveals that the domical vaults increase the longitudinal thrust and reduce the transverse thrust, which may require additional precautions to be taken during construction, but entails a less elaborate buttressing system. The domical vaults are found to perform well structurally, with an absence of tensile stresses, and are more suitable for a square bay. In general, the structural system of the nave of Santa Maria Novella is found to be the product of carefully considered structural design, which may be accepted as an alternative to the French Gothic construction system.  相似文献   
3.
Nonalcoholic fatty liver disease (NAFLD) is strongly associated to the features of metabolic syndrome which can progress to cirrhosis, liver failure and hepatocellular carcinoma. However, the most common cause of mortality in people with NAFLD is not liver-related but stems from atherosclerotic cardiovascular disease (CVD). The prevalence of NAFLD is on the rise, mainly as a consequence of its close association with two major worldwide epidemics, obesity and type 2 diabetes (T2D). The exact pathogenesis of NAFLD and especially the mechanisms leading to disease progression and CVD have not been completely elucidated. Human fetuin-A (alpha-2-Heremans Schmid glycoprotein), a glycoprotein produced by the liver and abundantly secreted into the circulation appears to play a role in insulin resistance, metabolic syndrome and inflammation. This review discusses the links between NAFLD and CVD by specifically focusing on fetuin-A’s function in the pathogenesis of NAFLD and atherosclerotic CVD.  相似文献   
4.
In this study, polyvinyl alcohol/organically modified montmorillonite (HDA/MMT; organoclay) composite was prepared for the intercalation processes. Firstly, the rheological behavior of aqueous montmorillonite dispersions was investigated as a function of solid content. Hexadecylamine (HDA) was added to the montmorillonite dispersion (2%, w/w) in different concentrations in the range of 5 × 10?4 – 9 × 10?3 mmol/L. The basal spacing of the organoclay (OMMT) was studied by X‐ray diffraction. The FTIR spectra are obtained from the modified montmorillonite products, which revealed the characteristic absorbencies after treatment with HDA. HDA/MMT/PVA composite, which was produced by the reaction of 1 wt % PVA solution with organoclay complex, is characterized by the rheology, electrokinetic, XRD, FTIR, and SEM techniques. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102:2315–2323, 2006  相似文献   
5.
In this study, an Artificial Bee Colony Algorithm (ABCA) is used to obtain the optimal size and location of viscous dampers in planar buildings to reduce the damage to the frame systems during an earthquake. The transfer function amplitude of the top displacement and the elastic base shear force evaluated at the first natural circular frequency of structures are chosen as objective functions. The damper coefficients of the added viscous dampers are taken into consideration as design variables in a planar building frame. Transfer function amplitude of the top displacement and the amplitude of the elastic base shear force at the fundamental natural frequency are minimized under an active constraint on sum of the damper coefficients of the added dampers. According to two specified objective functions, an optimization algorithm based on the ABCA is proposed. The proposed method is verified by a gradient-based algorithm; steepest direction search algorithm (SDSA). The proposed ABCA and the SDSA are applied to find the optimal damper distribution for a nine-storey planar building then the optimal damper allocation obtained from the ABCA is investigated to rehabilitate models of irregular planar buildings. The validity of the proposed method was demonstrated through a time history analysis of the optimal damper designs, which were determined based on the frequency domain using the ABCA. The numerical results of the proposed optimal damper design method show that the use of the ABCA can be a practical and powerful tool to determine the optimal damper allocation in planar building structures.  相似文献   
6.
In this study, the rheologic and colloidal characterizations of sodium montmorillonite (NaMMT) were examined. Hexadecylamine (CH3(CH2)15NH2, HDA) was added to the bentonite water dispersion (2%, w/w) in different concentrations in the range 5.6 × 10−4−9.4 × 10−3 mmol/l. The rheological and electrokinetic behaviour of aqueous montmorillonite dispersions was investigated as a function of solid content and HDA concentration. The basal spacings of the HDA/NaMMT composites were studied by X-ray diffraction. The FTIR spectra were obtained from the modified bentonite products, which revealed the characteristic absorbances after treatment with HDA.  相似文献   
7.
Modeling of hysteresis and power losses in transformer laminations   总被引:1,自引:0,他引:1  
In this paper, a method for the representation of hysteresis and power losses in the laminations of power transformers is proposed. The developed model is based on data supplied from steel manufacturer and able to predict hysteresis and eddy current losses.  相似文献   
8.
Polymer Bulletin - Drug carrier, poly(maleic anhydride-co-vinyl acetate) (MAVA or poly[MA-co-VA]) copolymer, was traditionally synthesized by free radical chain polymerization reaction, in methyl...  相似文献   
9.
Multimedia Tools and Applications - The increase in the number of social media users and smartphone usage has a positive relationship with the diversity of applications. People use mobile...  相似文献   
10.
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