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81.
82.
A new chromene derivative, 2-(4'',8''-dimethylnona-3''E,7''-dienyl)-8-hydroxy-2,6-dimethyl-2H-chromene (1) together with four known natural products, methylfarnesylquinone (2), isololiolide (3), pheophytin a (4), and β-carotene (5) were isolated from the brown alga Homoeostrichus formosana. The structure of 1 was determined by extensive 1D and 2D spectroscopic analyses. Acetylation of 1 yielded the monoacetylated derivative 2-(4'',8''-dimethylnona-3''E,7''-dienyl)-8-acetyl-2,6-dimethyl-2H-chromene (6). Compounds 1–6 exhibited various levels of cytotoxic, antibacterial, and anti-inflammatory activities. Compound 2 was found to display potent in vitro anti-inflammatory activity by inhibiting the generation of superoxide anion (IC50 0.22 ± 0.03 μg/mL) and elastase release (IC50 0.48 ± 0.11 μg/mL) in FMLP/CB-induced human neutrophils.  相似文献   
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84.
Torrefied almond shells and wood chips were incorporated into polypropylene as fillers to produce torrefied biomass‐polymer composites. The composites were prepared by extrusion and injection molding. Response surface methodology was used to examine the effects of filler concentration, filler size, and lignin factor (relative lignin to cellulose concentration) on the material properties of the composites. The heat distortion temperatures, thermal properties, and tensile properties of the composites were characterized by thermomechanical analysis, differential scanning calorimetry, and tensile tests, respectively. The torrefied biomass composites had heat distortion temperatures of 8–24°C higher than that of neat polypropylene. This was due to the torrefied biomass restricting mobility of polypropylene chains, leading to higher temperatures for deformation. The incorporation of torrefied biomass generally resulted in an increase in glass transition temperature, but did not affect melting temperature. Also, the composites had lower tensile strength and elongation at break values than those of neat polypropylene, indicating weak adhesion between torrefied biomass and polypropylene. However, scanning electron microscopy results did indicate some adhesion between torrefied biomass and polypropylene. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41582.  相似文献   
85.
A micromirror with large rotation angle and vertical displacement is proposed and developed. The proposed micromirror is actuated by newly developed prestress comb drive actuators, which exhibit no pull-in, no hysteresis, and large vertical displacement range characteristics. The micromirror was fabricated using commercially available PolyMUMPs. Experimental results indicated that the maximum rotation angle and vertical displacement of the device are 26 and 45 mum, respectively  相似文献   
86.
In this study, the electrochemical surface area (ESA) and specific activity are used to obtain a fair comparison of various activators used for electroless copper deposition (ECD). Different sizes (i.e., 27, 48, and 63 nm) of Pd nanocubes (NCs) enclosed by {1 0 0} facets were successfully synthesized for use as new activators. The results of an analysis based on mixed potential theory indicated that the specific activities in terms of deposition current densities for the 27, 48, and 63 nm NCs and 9 nm nanoparticles (NPs) were 0.31, 1.06, 0.93, and 0.13 mA cm?2ESA, respectively. From the results of electrochemical quartz crystal microbalance measurements, the specific activities calculated from the mean deposition rates of the 27, 48, and 63 nm NCs and 9 nm NPs were 29.62, 68.72, 54.77, and 9.72 μg cm?2 s?1, respectively. A specific activity order of 48 nm NC > 63 nm NC > 27 nm NC > 9 nm NP was obtained. The 48 nm Pd NCs exhibited the maximum activity towards the activation of the ECD bath.  相似文献   
87.
Many Fuzzy-PID controller schemes used in industry today are based on some sort of simplified fuzzy reasoning methods and PID parameters. We present a design for Fuzzy-PID controllers using a novel PSO-EP-based hybrid algorithm. We succeed in making mathematical calculations and in encouraging EP reproduction with PSO. The main advantage of our design is that the integration of the PSO-EP-based hybrid algorithm structure generates new parameters for the Fuzzy-PID control schemes. The proposed algorithm is an improved variant of PSO, a relatively recently introduced stochastic optimization strategy for Fuzzy-PID controllers that is investigated in this study. The function of Fuzzy-PID controllers is illustrated by means of a model of the induction motor control system and a higher-order numerical model.  相似文献   
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89.
This paper presents the application of a hybrid controller to the optimization of the movement of a mobile robot. Through hybrid controller processes, the optimal angle and velocity of a robot moving in a work space was determined. More effective movement resulted from these hybrid controller processes. The experimental scenarios involved a five-versus-five soccer game and a MATLAB simulation, where the proposed system dynamically assigned the robot to the target position. The hybrid controller was able to choose a better position according to the circumstances encountered. The hybrid controller that is proposed includes a support vector machine and a fuzzy logic controller. We used the method of generalized predictive control to predict the target position, and the support vector machine to determine the optimal angle and velocity required for the mobile robot to reach the goal. First, we used the generalized predictive control to predict the target position. Then, the support vector machine is used to classify the angle that must be followed by the mobile robot to reach the goal. Next, a fuzzy logic controller is designed to determine the velocity of the left and right wheels of the mobile robot. Thus generated, the velocity was optimized according to the measures obtained by the support vector machine. Finally, based on the optimal velocity of robot, the output membership function was modified. Consequently, the proposed hybrid controller allowed the robot to reach the goal quickly and effectively.  相似文献   
90.
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