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1.
Cellulose dissolved in ionic liquid (1‐(carboxymethyl)pyridinium chloride)/water (60/40 w/w) mixture is regenerated in various non‐solvents, namely water, ethanol, methanol and acetone, to gain more insight into the contribution of non‐solvent medium to the morphology of regenerated cellulose. To this end, the initial and regenerated celluloses were characterized with respect to crystallinity, thermal stability, chemical structure and surface morphology using wide‐angle X‐ray diffraction, thermogravimetric analysis, Fourier transform infrared spectroscopy and scanning electron microscopy. According to the results, regardless of non‐solvent type, all regenerated samples have the same chemical structure and lower crystallinity in comparison to the initial cellulose, making them a promising candidate for efficient biofuel production based on enzymatic hydrolysis of cellulose. The reduction in crystallinity of regenerated samples is explained based on the potential of the non‐solvent to break the hydrogen bonds between cellulose chains and ionic liquid molecules as well as the affinity of water and non‐solvent which can be evaluated based on Hansen solubility parameter. The latter also determines the phase‐separation mechanism during the regeneration process, which in turn affects surface morphology of the regenerated cellulose. The pivotal effect of regenerated cellulose crystallinity on its thermal stability is also demonstrated. Regenerated cellulose with lower crystallinity is more susceptible to molecular rearrangement during heating and hence exhibits enhanced thermal stability. © 2019 Society of Chemical Industry  相似文献   
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To diminish heart failure development after acute myocardial infarction (AMI), several preclinical studies have focused on influencing the inflammatory processes in the healing response post-AMI. The initial purpose of this healing response is to clear cell debris of the injured cardiac tissue and to eventually resolve inflammation and support scar tissue formation. This is a well-balanced reaction. However, excess inflammation can lead to infarct expansion, adverse ventricular remodeling and thereby propagate heart failure development. Different macrophage subtypes are centrally involved in both the promotion and resolution phase of inflammation. Modulation of macrophage subset polarization has been described to greatly affect the quality and outcome of healing after AMI. Therefore, it is of great interest to reveal the process of macrophage polarization to support the development of therapeutic targets. The current review summarizes (pre)clinical studies that demonstrate essential molecules involved in macrophage polarization that can be modulated and influence cardiac healing after AMI.  相似文献   
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A group of drugs used in intra-arterial chemotherapy (IAC) have intrinsic ionic properties, which can be used for filtering excessive drugs from blood in order to reduce systemic toxicity. The ion-exchange mechanism is utilized in an endovascular Chemofilter device which can be deployed during the IAC for capturing ionic drugs after they have had their effect on the tumor. In this study, the concentrated solution theory is used to account for the effect of electrochemical forces on the drug transport and adsorption by introducing an effective diffusion coefficient in the advection–diffusion–reaction equation. Consequently, a multi-physics model coupling hemodynamic and electrochemical forces is developed and applied to simulations of the transport and binding of doxorubicine in the Chemofilter device. A comparison of drug adsorption predicted by the computations to that measured in animal studies demonstrated the benefits of using the concentrated solution theory over the Nernst–Plank relations for modeling drug binding.  相似文献   
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In this paper, a numerically comprehensive investigation have been performed in order to propose a high-κ spacer triple-gate junctionless FinFET (HKS  相似文献   
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It is well-known that polymer nanocomposites can bring about superior mechanical, thermal, optical, physical, and chemical properties in comparison with pure polymers. In this study, different contents of unmodified silica nanoparticles (Si-Un), surface modified nano-silica by octylsilane (Si-OS), and surface modified nano-silica by polydimethylsiloxane (Si-PDMS) are added to the polyurethane (PU) matrix and their effects on the physical properties of the polymer examined. The experimental results indicate that most of the nanocomposites have a higher tensile strength and elongation. In addition, hyperelastic energy function models have been used to model the stress-strain relation of the nanocomposites. In this study, Mooney-Rivlin, neo-Hookean, Rivlin general polynomial, and Davies-De Thomas (DDT) models have been investigated, possessing respectively, two, one, eight, and three constants to be determined. The differential evolution (DE) optimization method, a strong heuristic optimization algorithm, has been used to find the constants; in which the absolute summation of the differences between the models’ predictions and experimental data is taken into account as the objective function and the models’ constants are considered as the decision variables. Moreover, equation constants are found by using regression, an indicator of DE optimization superiority. The results show that even though the Rivlin general polynomial model provides the most accurate prediction, the DDT model, consisting of three constants, can be considered as the most acceptable one.  相似文献   
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In spite of the classic approaches of solution of dynamic facility layout problem, which only material handling and rearrangement costs are considered as objective function, these problems are the multi-objective problems. In this paper, a mixed integer linear programming formulation is presented for multi-objective dynamic facility layout problem concerning flexible bay structure. In addition, three current objectives in dynamic facility layout problems including minimizing material handling and rearrangement costs, maximizing adjacency rate, and minimizing shape ratio difference have been considered. Also, for solving this problem, two methods including the GAMS software and proposed parallel variable neighborhood search (PVNS) algorithm are used. So, it is worth mentioning that four test problems are solved by them, and the results show that the proposed PVNS algorithm is more efficient than the GAMS software.  相似文献   
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There is a paucity of data in respect of the nutritional quality of complementary foods for infants and young children aged between 6 and 12 months. The primary objective of this study was to examine nutritive values of such complementary infant food on the UK market in order to ascertain their suitability relative to dietary guidelines for the 6–9 months age group. Quantitative analyses were conducted on eight different products representing four popular brands (meat and vegetable based) currently on sale in the UK. Eight major mineral and trace elements, namely: calcium, copper, magnesium, iron, zinc, potassium, sodium and selenium were measured by ICP–OES and ICP–MS. The results of these studies were referenced to the Recommended Nutrient Intake (RNI) values for 6–9 months old children, and a menu of entire daily intake of minerals and trace elements was composed taking into consideration the nutrient and energy intake from milk consumption. Based on these comparisons, all the food samples studied in this work contained less essential minerals than expected from the RNI values except for potassium in meat and vegetable based recipes. These results suggest that commercial complementary infant foods on the UK market may not contain the minimum levels of minerals required for the labelling declaration of micronutrient content (Commission Directive 2006/125/EC). This provides opportunities and scope for product optimisation to improve their nutritive value.  相似文献   
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