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71.
We propose a self-assembled and anisotropically metal loaded large area PS-b-P4VP diblock copolymer film as a medium with hyperbolic dispersion for application in superlensing and nanolithography. We obtained domain sizes from 30 to 100 nm with successful demonstration of metal loading inside the nano-templates. The separation between the individual nanorods and their radius was effectively controlled by varying the molecular weights and compositions of the polymers. We apply Maxwell–Garnett homogenization and FDTD simulations to show the sub-wavelength imaging and lithography potential of these hyperbolic metamaterials (HMMs). A proof of principle nanolithography result demonstrates sub-wavelength imaging and lithography using the proposed HMMs.  相似文献   
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73.
We have made an attempt to develop the quaternionic formulation of Yang–Mill’s field equations and octonion reformulation of quantum chromo dynamics (QCD). Starting with the Lagrangian density, we have discussed the field equations of SU(2) and SU(3) gauge fields for both cases of global and local gauge symmetries. It has been shown that the three quaternion units explain the structure of Yang–Mill’s field while the seven octonion units provide the consistent structure of SU(3) C gauge symmetry of quantum chromo dynamics.  相似文献   
74.
We perform two-photon coincidence subwavelength interference experiments from double slit using independent photons obtained from a pseudo-thermal light source produced by (i) slowly rotating ground glass (RGG) with turbid solution of a different density and (ii) RGG. The turbid solution is water solution containing 3 μm diameter polystyrene microspheres. It is found that the visibility of the obtained interference pattern decreases in first experiment with increasing the density of the turbid solution from N = 1010 spheres m−3 to N = 1014 spheres m−3. However, the results are reported here for the density of N = 1014 spheres m−3. The visibility obtained with RGG with turbid solution having N = 1014 spheres m−3is 23% which increases to 27% with RGG but the resolution decreases. The effect of coherence width of source in two-photon interference pattern is also studied with pseudo-thermal light obtained by RGG. It was observed that on increasing the coherence width the visibility of interference fringes increased and quality of the fringe reduced and when the coherence width was more then slit separation, in coincidence measurements, no interference pattern appeared. The results are used to explore the classical subwavelength interference nature with thermal light.  相似文献   
75.
In this paper, we give a counterexample to Lemma 2.2 proved by Song-il Ri (2016). Further, we improve the result of Song-il Ri by employing a proper setting.  相似文献   
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We have constructed some Regge trajectories for mesons and baryons by taking the 70 MeV spinless mass quanta as the ultimate building block for the light hadrons. In order to make masses integral multiples of seventy, small changes in masses has been made with due explanation. We have shown how a linear relationship between J and M 2 is maintained by considering quantized hadron masses, which is a direct consequence of the string model and gives a strong clue for quark confinement. It has also been established that mesons and baryons have different slopes and the slopes of baryons is less than the slope of the mesons. This clearly defies the concept of universality of slopes (α ≈ 1.1 GeV2) of hadrons, which can only be achieved if the strings joining the quarks have constant string tension α = 1/(2πσ) (where σ is the string tension).  相似文献   
78.
    
The ring‐opening polymerization of a monomer containing a free carboxylic acid group is reported for the first time. The monomer, 5‐methyl‐5‐carboxyl‐1,3‐dioxan‐2‐one (MCC), was copolymerized with trimethylene carbonate (TMC) in an enzymatic ring‐opening polymerization conducted in bulk at 80 °C. The low‐melting TMC comonomer also solubilized the high‐melting MCC monomer, allowing for solvent‐free polymerizations. Six commercially available lipases were screened, and Candida antarctica lipase‐B (Novozym‐435) and Pseudomonas cepacia lipase were selected to catalyze the copolymerization because of their higher monomer conversions. Higher molecular weight polymers (weight‐average molecular weight = 7800–9200) were prepared when Novozym‐435 was used, with less MCC incorporated into the copolymer than used in the monomer feed. However, Pseudomonas cepacia lipase showed good agreement between the molar feed ratios and the molar composition, but the molecular weights (weight‐average molecular weight = 3600–4800) were lower than those obtained when Novozym‐435 was used. 13C NMR spectral data were used for microstructural analysis, which suggested the formation of random, linear, and pendant carboxylic acid groups containing polycarbonates with hydroxyl groups at both chain ends. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 1267–1274, 2002  相似文献   
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Study of relativistic effects in the interaction of a spin-1/2 electric charge in the radial field of a spin less point like dyon has been undertaken using Dirac’s relativistic equation. Angular momentum and energy eigen values have been obtained. The deviations of the results from those of hydrogen atom like systems have been discussed.  相似文献   
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