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Moradi  Marjan  Rastakhiz  Nahid  Ghaedi  Mehrorang  Zhiani  Rahele 《Catalysis Letters》2021,151(6):1653-1662
Catalysis Letters - Nitro-aromatic pollution in industrial waste streams threat wellbeing of water resources. This study investigates the performance of a copper-based nano catalyst to reduce...  相似文献   
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Catalysis Letters - Industrial Cu/ZnO/Al2O3 or novel rate catalysts, prepared with a photochemical deposition method, were studied under functional CH3OH synthesis conditions at the set temperature...  相似文献   
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The effect of multi-ions (Mg2+, SiO44-, Zn2+, Cu2+) doping on the properties of carbonated hydroxyapatite (CHA) prepared by a wet chemical method has been investigated. Different combinations of ions were doped into the CHA and the as-synthesized compacts were sintered at 900?°C prior to body characterization. It was found that regardless of ions doping, the lattice structure of the CHA was not disrupted. In addition, secondary phases were not detected for all the multi-ions doped samples. The XRD and FTIR results further confirmed the presences of a B-Type CHA in the sintered samples. The XRD analysis revealed that the lattice parameters (c/a ratio) increased with dopant addition and resulted in a smaller crystallite size. The FESEM examination also showed the presences of smaller grain size for the multi-ions doped CHA samples thus indicating that the doping was beneficial in suppressing grain coarsening in carbonated hydroxyapatite.  相似文献   
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Framework-based development is currently regarded as one of the most promising software development approaches when it comes to improvements in lead time, productivity and quality. However, many frameworks and projects based on frameworks still report failures, which indicate that there are problems related to both frameworks technology and frameworks usage. The objective of our research was to examine the major drivers that have an impact on a framework’s acceptance and a framework’s success. We used the technology acceptance model (TAM) and Seddon’s information systems success model as our underlying theory. Data collected from an online survey of 389 active framework users was used to test hypothesized models. Data analysis was performed via structural equation modeling. Our findings support the post-adoption version of TAM and the relationship between continuous use and the successful use of systems, where more use also means more net benefits. We found that the successful use of frameworks is mainly dependent on two factors: continuous framework usage intention and the perceived usefulness of the framework. Several practical and theoretical implications can be foreseen including advances in framework development guidelines and insight into the relationship between the acceptance and success of frameworks.  相似文献   
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Biology is inherently parallel. Models of biological systems and bio-inspired algorithms also share this parallelism, although most are simulated on serial computers. Previous work created the systemic computer – a new model of computation designed to exploit many natural properties observed in biological systems, including parallelism. The approach has been proven through two existing implementations and many biological models and visualizations. However to date the systemic computer implementations have all been sequential simulations that do not exploit the true potential of the model. In this paper the first ever parallel implementation of systemic computation is introduced. The GPU Systemic Computation Architecture is the first implementation that enables parallel systemic computation by exploiting the multiple cores available in graphics processors. Comparisons with the serial implementation when running two programs at different scales show that as the number of systems increases, the parallel architecture is several hundred times faster than the existing implementations, making it feasible to investigate systemic models of more complex biological systems.  相似文献   
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Polyaniline‐graft‐Poly(N‐isopropylacrylamide) copolymers were synthesized by atom‐transfer radical polymerization (ATRP) of N‐isopropylacrylamide using polyaniline macro‐initiators. Polyaniline‐chloroacetylchloride and polyaniline‐chloropropionylchloride macroinitiators were obtained by the reaction of amine nitrogens of polyaniline with chloroacetyl chloride and 2‐choloropropionyl choloride, respectively. Both macroinitiators and graft copolymers were characterized by FT‐IR and 1H‐NMR spectroscopy. The cyclic voltammetry (CV) and UV‐Vis spectroscopy studies showed that these copolymers are electroactive. The solubility test revealed that the polyaniline‐graft‐poly (N‐isopropylacrylamide) copolymers are water soluble or water/methanol soluble. The Atomic Force Microscopy (AFM) and Scanning Electron Microscopy (SEM) images showed the growing of poly (N‐isopropylacrylamide) chains on polyaniline backbone. Investigation of thermal behavior of graft copolymers by thermal gravimetry analysis (TGA) confirmed the results obtained from AFM and SEM images. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   
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The aim was to investigate mechanisms contributing to quercetin's previously described effects on cell-proliferation and -differentiation, which contradicted its proposed anticarcinogenic potency. In a 10-day experiment, 40 microM quercetin stabilized by 1 mM ascorbate reduced Caco-2 differentiation up to 50% (p < 0.001). Caco-2 RNA from days 5 and 10, hybridized on HG-U133A2.0 Affymetrix GeneChips(R), showed 1,743 affected genes on both days (p < 0.01). All 14 Caco-2 differentiation-associated genes showed decreased expression (p < 0.01), including intestinal alkaline phosphatase, that was confirmed technically (qRT-PCR) and functionally (enzyme-activity). The 1,743 genes contributed to 27 pathways (p < 0.05) categorized under six gene ontology (GO) processes, including apoptosis and cell-cycle. Genes within these GO-processes showed fold changes that suggest increased cell-survival and -proliferation. Furthermore, quercetin down-regulated expression of genes involved in tumor-suppression and phase II metabolism, and up-regulated oncogenes. Gene expression changes mediated by ascorbate-stabilized quercetin were concordant with those occurring in human colorectal carcinogenesis ( approximately 80-90%), but were opposite to those previously described for Caco-2 cells exposed to quercetin without ascorbate ( approximately 75-90%). In conclusion, gene expression among Caco-2 cells exposed to ascorbate-stabilized quercetin showed mechanisms contrary to what is expected for a cancer-preventive agent. Whether this unexpected in vitro effect is relevant in vivo, remains to be elucidated.  相似文献   
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Developing a Pt-based electrocatalytic material able to selectively catalyze hydrogen oxidation (HOR) while supressing oxygen reduction (ORR) is beneficial for durability of the fuel cells. Namely, degradation of carbon supported Pt particles is dramatically influenced by the unwanted ORR enrolling at the anode due to the air penetration during start-up/shut-down events. We present an organic matrix tris(aza)pentacene (TAP), which belongs to π-functional materials with ladder-like conjugated nitrogen-containing units, as the support for Pt to form a “smart” fuel cell anode able to selectively catalyze HOR and to suppress ORR. “Switching-on/off” of the composite material activity is provided by reversible reduction/oxidation of the TAP in the low potential region which provokes TAP - HxTAP transition. Conductivity of the reduced HxTAP enables supported Pt particles to effectively run HOR. In contrast, restricted conductivity of oxidized TAP analogue leads to the substantial drop in the ORR activity with respect to benchmark Pt/C catalyst.  相似文献   
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