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991.
The development of wide color gamut (WCG) liquid crystal display (LCD) plays an important role in the high‐quality television (TV) field. Nowadays, people want their TV or display devices to have the capability of showing vivid colors while keeping skin colors as natural as they remember. Therefore, it is necessary to develop color‐correction technologies for WCG LCD system. A new color‐correction method named “natural skin‐color mapping algorithm” (NSCMA) for WCG LCD is proposed in this study. It can solve the skin‐color contour problem in color‐corrected images with simple skin‐color detection. Its development is based on the concepts of performing color mapping between source hue colors and target hue colors on each hue page. The polynomial regression is also applied to calculate the color mapping conversion matrices. Two color mapping factors called template‐size factor and tone‐compression factor are designed in NSCMA. The template‐size factor is used to adjust target template sizes adequately. The tone‐compression factor is designed to control the degrees of image enhancement. For facial skin‐color pictures, the appropriate settings of template‐size factor and tone‐compression factor will get suitable color image rendering on the WCG LCD. It is demonstrated that the WCG LCD can be corrected to show vivid color pictures and keep facial skin colors as natural as possible when the proposed NSCMA is performed. © 2010 Wiley Periodicals, Inc. Col Res Appl, 2011  相似文献   
992.
The development of a novel TiN-reinforced silicon nitride/silicon oxynitride composite using an innovative in situ TiN-forming technique was investigated. Silicon powder compacts containing various amounts of TiO2 (anatase structure) and sintering additives were nitrided under N2 atmosphere and then further densified by hot pressing. The microstructure of the resultant composite was analyzed by X-ray diffraction, scanning electron microscopy, and solid-state nuclear magnetic resonance spectroscopy. The results of this study show that TiO2 can be successfully converted to TiN during the nitridation of Si + TiO2 mixture. The TiO2 content affects not only the microstructure of the matrix but also the composition of the intergranular phase. The type and amount of sintering additives also show a significant effect on the microstructural development of the composite.  相似文献   
993.
Poison ivy, Toxicodendron radicans, and poison oaks, T. diversilobum and T. pubescens, are perennial woody species of the Anacardiaceae and are poisonous, containing strong allergens named urushiols that cause allergic contact dermatitis. Poison ivy is a species distributed from North America to East Asia, while T. diversilobum and T. pubescens are distributed in western and eastern North America, respectively. Phylogreography and population structure of these species remain unclear. Here, we developed microsatellite markers, via constructing a magnetic enriched microsatellite library, from poison ivy. We designed 51 primer pairs, 42 of which successfully yielded products that were subsequently tested for polymorphism in poison oak, and three subspecies of poison ivy. Among the 42 loci, 38 are polymorphic, while 4 are monomorphic. The number of alleles and the expected heterozygosity ranged from 1 to 12 and from 0.10 to 0.87, respectively, in poison ivy, while varied from 2 to 8 and, from 0.26 to 0.83, respectively in poison oak. Genetic analysis revealed distinct differentiation between poison ivy and poison oak, whereas slight genetic differentiation was detected among three subspecies of poison ivy. These highly polymorphic microsatellite fingerprints enable biologists to explore the population genetics, phylogeography, and speciation in Toxicodendron.  相似文献   
994.

Abstract

The interactions between phonons and electrons induced by the dopants or the substrate of graphene in spectroscopic investigation reveal a rich source of interesting physics. Raman spectra and surface-enhanced Raman spectra of supported and suspended monolayer graphenes were measured and analyzed systemically with different approaches. The weak Raman signals are greatly enhanced by the ability of surface-enhanced Raman spectroscopy which has attracted considerable interests. The technique is regarded as wonderful and useful tool, but the dopants that are produced by depositing metallic nanoparticles may affect the electron scattering processes of graphene. Therefore, the doping and substrate influences on graphene are also important issues to be investigated. In this work, the peak positions of G peak and 2D peak, the I2D/IG ratios, and enhancements of G and 2D bands with suspended and supported graphene flakes were measured and analyzed. The peak shifts of G and 2D bands between the Raman and SERS signals demonstrate the doping effect induced by silver nanoparticles by n-doping. The I2D/IG ratio can provide a more sensitive method to carry out the doping effect on the graphene surface than the peak shifts of G and 2D bands. The enhancements of 2D band of suspended and supported graphenes reached 138, and those of G band reached at least 169. Their good enhancements are helpful to measure the optical properties of graphene. The different substrates that covered the graphene surface with doping effect are more sensitive to the enhancements of G band with respect to 2D band. It provides us a new method to distinguish the substrate and doping effect on graphene.

PACS

78.67.Wj (optical properties of graphene); 74.25.nd (Raman and optical spectroscopy); 63.22.Rc (phonons in graphene)  相似文献   
995.
The measurement of particle size distributions using electrical mobility can be accelerated significantly by an alternate mode of operating mobility instruments. Rather than changing the electric field in discrete steps to select particles in a given mobility range, the electric field can be scanned continuously. The particles are classified in a time-varying electric field, but for an exponential ramp in the field strength there remains a one-to-one correspondence between the time a particle enters the classifier and the time it leaves. By this method, complete scans of mobility with as many as 100 mobility measurements have been made in 30 seconds using a differential mobility classifier with a condensation nuclei counter as a detector.  相似文献   
996.
The thermal conductivity of Cu/Al2O3 bilayers prepared by a direct-bonding technique was determined. The direct-bonding process started with the pre-oxidation treatment of a Cu plate at a temperature less than 600 °C. Though a thin oxide layer was located on the surface of the plate after treatment, the oxygen solutes began to diffuse into the interior of Cu plate prior to bonding. Bonding occurred by a eutectic liquid formed at 1075 °C. No reaction interphase was observed at the Cu–Al2O3 interface. The thermal resistance of the Cu/Al2O3 interface is very low. The extremely low thermal resistance can be related to the clean interface between the two materials.  相似文献   
997.
This study proposes a novel ejector‐pins compression system (EPCS) to improve the mechanical strength of weld lines that are formed in the injection molding process. Weld lines are significant defects that affect injection molding quality, causing the poor appearance and low mechanical strength of injection‐molded parts. In this experiment, several ejector pins are placed intentionally near the weld lines appearing, and are initially sunken beneath the cavity surface to form a reflow trap such that some of the molten plastics are allowed to flow into it during the filling process. These molten plastics are then compressed by the arisen ejector pins. Accordingly, the compressed molten plastics reflow through the weld lines, disordering the molecular orientation. Experimental verification revealed that the use of an EPCS can efficiently eliminate the orientation of the molecules parallel to the weld line. The specimens' impact strength of using EPCS can increase to between one and two times than that of conventionally injection‐molded. Therefore, this simple and novel method is feasible for greatly improving the mechanical strength of weld lines. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2013  相似文献   
998.
We describe the preparation of vinyl‐terminated benzoxazine‐functionalized graphene using free radical grafting. The resulting functionalized graphene (f‐graphene) was incorporated into bis(3‐allyl‐3,4‐dihydro‐2H‐1,3‐benzoxazinyl)methane (V‐BF‐a) monomer in order that nanocomposites could be prepared. Results of scanning electron microscopy and transmission electron microscopy revealed that the sheets of f‐graphene were well dispersed throughout the matrix, and there was a strong interfacial interaction between the f‐graphene and polyV‐BF‐a. The inclusion of f‐graphene into the nanocomposites resulted in a material with a high thermal stability and a low coefficient of thermal expansion (CTE); increasing the content of f‐graphene reduced the CTE significantly more. A reduction in the CTE of up to 48% was produced by adding just 1 wt% of f‐graphene; this corresponded to an increase of 12 °C in the glass transition temperature. These results suggest that f‐graphene nanocomposites can be ‘tuned’ to give materials with both a low CTE and a high thermal stability, and that graphene composites of this type can thus be manufactured to withstand a wider range of temperatures.  相似文献   
999.
Monoethanolamine (MEA)-complexed cupric ion solution was used as a non-ammoniacal solution for copper etching on printed circuit boards (PCB). The copper dissolution behaviour of this MEA-complexed cupric solution containing 1 M CuCl2 and 3.3 to 10 M MEA was studied by the potentiodynamic method at various temperatures (25–55 °C) and pH values (10–6.5). The effects of these factors on dissolution rate and etching factor of the copper patterns of PCBs were discussed. It was found that the highest corrosion current density (i corr) was obtained with MEA concentration at about 5 M. Activation energies (E a) of MEA-complexed cupric solutions were measured and the heat of adsorption (H ads), which accounts for the chemisorption of the MEA ligands on the copper surface was calculated. H ads was found to increase with solution containing excess MEA ([MEA] > 5 M), indicating the inhibition behaviour of MEA. Hence with lower pH, i corr increased because the concentration of MEA ligands decreased due to acid reaction. The etching factor of copper patterns of PCBs with 75 m/75 m, line/space (L/S), were also tested by spray etching method. A high etching factor can be achieved for etchants containing high MEA concentration, which means MEA affects the etching factor since the inhibitive property of MEA reduces the undercut. Although the etching rate of MEA-complexed cupric etchant is still much lower than the ammoniacal etchant, the etching factor of the forward etchant (>3) is better than the latter (<2).  相似文献   
1000.
This study examined ethylene–vinyl acetate (EVA)‐toughened polystyrene (PS). EVA is well‐known to be incompatible with PS; thus, the PS graft to the EVA backbone (EVA‐g‐PS) was used as a compatibilizer and provided good adhesion at the interface of PS and EVA. In addition, the mechanical properties and impact resistance of the PS matrix were obviously improved by EVA‐g‐PS and by EVA itself. Meanwhile, differential scanning calorimetry results showed that the grafted PS chain influenced the crystallization of EVA; for example, the melting temperature, the crystallization temperature, and the percentage crystallinity related to EVA were reduced. Moreover, the addition of 10% EVA increased the impact strength by a factor of five but reduced the modulus by the same factor. Additionally, a lower number‐average molecular weight EVA delayed phase inversion and resulted in poor mechanical properties. A fracture surface photograph revealed that the major mechanism of EVA‐toughened PS was craze and local matrix deformation. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 699–705, 2003  相似文献   
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