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191.
Zinc aluminum hydrotalcite intercalated with molybdate (HTM) and modified by 3-glycidoxypropyltrimethoxysilane (HTM-GS) was prepared and incorporated into a waterborne epoxy coating. The synthesized HTM-GS was characterized by FTIR, XRD, SEM, and TEM. The inhibitive action of HTM-GS on carbon steel was evaluated using electrochemical measurement and SEM/EDX analysis. The corrosion protection of the waterborne epoxy coating containing HTM-GS was evaluated and compared to that of the pure waterborne epoxy coating and the waterborne epoxy coating containing HTM by salt spray test and adhesion measurement. It was shown that the molybdate was intercalated in the hydrotalcite structure and the molybdate contents in HTM and HTM-GS were 16.0 and 13.2 wt%, respectively. The polarization curves obtained on the carbon steel electrode showed that HTM and HTM-GS are anodic corrosion inhibitors, and their inhibition efficiencies at concentration of 3 g/l were 92.0 and 94.7%, respectively. Additionally, HTM and HTM-GS at concentration of 0.5 wt% improved corrosion resistance and adhesion of waterborne epoxy coatings. Surface modification by 3-glycidoxypropyltrimethoxysilane ameliorated the dispersion of HTM in epoxy matrix and the effect of HTM on protection properties of waterborne epoxy coating.  相似文献   
192.
Perovskite oxides like SrTiO3 at the nanoscale are of interest for emerging applications,including high-k dielectrics and sensors.However,their synthesis requires long calcination at the elevated temperature,which is a barrier of their application to flexible electronics.Here,an effective laser-assisted sol-gel method to patternably produce SrTiO3 nanoparticles (-100 nm) in selective areas on polyimide substrates (coated with ITO) is introduced.Importantly,the violet-laser power is just 1 W but sufficient to crystallize the material in a short period (a few seconds).Furthermore,developing a flexible device platform using carbon nanotubes (CNT) and SrTiO3 nanoparticles for detection of humidity changes at room temperature is proposed.The sensor platform has both capacitive and resistive sensing abilities.The resistive mode with a lower power usage (about 0.2 μW) is suitable for long monitoring of humidity in the range of 2% RH and above.The capacitive mode with higher sensitivity,faster response/recovery time (1-3 min),and lower detection limit (0.5% RH) can be used for calibration purposes.The performance of the flexible sensor is still maintained after 5000 bending cycles at 1.5-cm radius.Altogether,our synthesis method and the flexible sensor show chances for mass-producing perovskite oxides at low cost for wearable electronics.  相似文献   
193.
Compression creep tests (CCTs) have been widely used in phenomenological characterization of viscoelastic materials such as glasses. However, disturbed by specimen-tool interface friction, the real stress-strain data regarding the pure viscoelastic deformation are frequently misestimated in conventional CCTs, causing decreased accuracies of the derived viscoelastic parameters. This study proposes a comprehensive CCT-based approach to develop a viscoelastic model with weakened frictional disturbance and enhanced predictive accuracy. An integrated calculation procedure is first built to mathematically characterize the frictional and viscoelastic behaviors of glass during compression. Uniaxial CCTs of a typical borosilicate glass (L-BAL42) are then performed at varied frictional conditions. The quantified coefficients of interface friction indicate that a minor frictional disturbance is achieved when Nickel foils are used as interfacial layers, whereby a more realistic viscoelastic constitutive relation of the glass is derived. The obtained frictional and viscoelastic constants are further incorporated into computational modeling of the CCT and precision molding processes. The demonstrated consistencies between the simulated and measured results (creep displacement and molding force) suggest that, by technically slashing the interface friction and theoretically correcting the friction-involved stress in CCTs, the frictional disturbance to experimental stress-strain data can be effectively weakened, and a viscoelastic model of enhanced predictive accuracy can be thus developed.  相似文献   
194.
Highly ordered SBA‐16 silica mesoporous materials were synthesised hydro‐solvothermally under the acidic medium using SiO2/F127/BuOH/HCl/H2O gel. Pure SiO2 powders were prepared from inexpensive and environmentally friendly silica source of rice husk. The pore size of the materials could be optimised by using a blend of P123 and F127 templates. Sn‐substituted SBA‐16 mesoporous materials were yielded via the direct injection of stannic chloride into the fixed gel in acidic medium. X‐ray diffraction, N2 adsorption, scanning electron microscope/transmission electron microscope results suggest that tin ions were incorporated into the Si‐SBA‐16 framework by isomorphous substitution between Sn and Si ions. Elemental analysis indicates that tin can be substituted in the range of Si/Sn = 21.4–10.5. UV–vis, XPS, TPR‐H2, TPD‐NH3 results reveal that tin atoms are highly dispersed in 4+ oxidation state and mostly occupy in the silica framework. The degree of tin incorporation into silica framework can easily be controlled by a simply adjustment of the H2O and HCl molar ratios. The mesoporous Sn‐SBA‐16 materials were an active benzylation catalyst with almost 100% selectivity to monoalkylated product in alkylation of aromatics with benzyl chloride. © 2011 Canadian Society for Chemical Engineering  相似文献   
195.
The hypothalamic arcuate nucleus (Arc) is a central unit that controls the appetite through the integration of metabolic, hormonal, and neuronal afferent inputs. Agouti-related protein (AgRP), proopiomelanocortin (POMC), and dopaminergic neurons in the Arc differentially regulate feeding behaviors in response to hunger, satiety, and appetite, respectively. At the time of writing, the anatomical and electrophysiological characterization of these three neurons has not yet been intensively explored. Here, we interrogated the overall characterization of AgRP, POMC, and dopaminergic neurons using genetic mouse models, immunohistochemistry, and whole-cell patch recordings. We identified the distinct geographical location and intrinsic properties of each neuron in the Arc with the transgenic lines labelled with cell-specific reporter proteins. Moreover, AgRP, POMC, and dopaminergic neurons had different firing activities to ghrelin and leptin treatments. Ghrelin led to the increased firing rate of dopaminergic and AgRP neurons, and the decreased firing rate of POMC. In sharp contrast, leptin resulted in the decreased firing rate of AgRP neurons and the increased firing rate of POMC neurons, while it did not change the firing rate of dopaminergic neurons in Arc. These findings demonstrate the anatomical and physiological uniqueness of three hypothalamic Arc neurons to appetite control.  相似文献   
196.
Tristetraprolin (TTP), an RNA-binding protein, controls the stability of RNA by capturing AU-rich elements on their target genes. It has recently been identified that TTP serves as an anti-inflammatory protein by guiding the unstable mRNAs of pro-inflammatory proteins in multiple cells. However, it has not yet been investigated whether TTP affects the inflammatory responses in the hypothalamus. Since hypothalamic inflammation is tightly coupled to the disturbance of energy homeostasis, we designed the current study to investigate whether TTP regulates hypothalamic inflammation and thereby affects energy metabolism by utilizing TTP-deficient mice. We observed that deficiency of TTP led to enhanced hypothalamic inflammation via stimulation of a variety of pro-inflammatory genes. In addition, microglial activation occurred in the hypothalamus, which was accompanied by an enhanced inflammatory response. In line with these molecular and cellular observations, we finally confirmed that deficiency of TTP results in elevated core body temperature and energy expenditure. Taken together, our findings unmask novel roles of hypothalamic TTP on energy metabolism, which is linked to inflammatory responses in hypothalamic microglial cells.  相似文献   
197.
Wireless Personal Communications - Content Addressable Memory (CAM) is used in high speed searching applications and also in data compression. Recently in the network computing era, fast lookup...  相似文献   
198.
Multimedia Tools and Applications - Data partition with high confidence is one of the main concentration of researchers in Soft Computing for many years. It is known that there may be some data...  相似文献   
199.
200.
Supplier selection is a vital part of the supply chain and is also a current issue that concerns businesses today as supplier quality directly affects the operations of the organization. Choosing the right supplier can help businesses increase productivity, competitiveness in the market, and profits without having to lower the quality of the products. However, choosing a supplier is not a simple matter, it requires businesses to consider many aspects about their suppliers. Therefore, the goal of this study is to propose an integrated model consisting of two models: Fuzzy Analytics Network Process (Fuzzy-ANP) model and Weighted Aggregated Sum Product Assessment (WASPAS) to solve the problem above. The Fuzzy-ANP model was developed to evaluate the weightings of the supplier selection criteria, and the WASPAS Model was used to rank the suppliers. An example of supplier selection in the coffee industry in Vietnam was studied to validate the model, namely 5 main criteria, with 16 sub-criteria, and 7 suppliers. The model test results show that the Fuzzy ANP and WASPAS integration model was suitable. In future, these developing models can apply to other industries or integrate with other models.  相似文献   
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