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81.
In this paper, the graybody radiation phenomena has been handled with the help of fractional calculus. Fractional definition of graybody spectrum has been written in terms of Mittag‐Leffler function. The obtained data from fractional calculus approximation for nearly 2.87 × 107 K have been compared with literature values and standard blackbody radiation.  相似文献   
82.
A DNA probe that was based on methylene blue (MB) imprinted polyvinyl pyridine polymer (MIP) modified carbon paste electrodes were developed for the first time for electrochemical monitoring of DNA. Probes were built up by adsorbing MB onto modified electrodes prior to DNA immobilization. It was shown that DNA strongly immobilizes on MIP modified electrodes when MB was adsorbed in advance of DNA immobilization. The performance of the MB imprinted polymer modified carbon paste electrodes (MIP‐CPE) to rebind the template molecule (MB) were compared to those of control polymer modified (non‐imprinted polymer NIP‐CPE) and bare (CPE) electrodes. Electrochemical signal resulting from the oxidation of guanine moiety of the immobilized probe DNA was high enough on the constructed platform, implicating that probes of this kind could be favorably used for DNA analysis. These probes exhibited high selectivity for its complementary DNA sequences (target). HBV‐DNA hybridization was studied to evaluate the selectivity of the probes for complementary, non‐complementary and mismatch sequences. The detection limit of the probe for the target DNA was 8.72 µg/mL (1.38 µM), which was better than those attained by some earlier DNA sensor studies.  相似文献   
83.
The double emulsion technology has a potential effect on the development of diversity and quality of functional foods by means of decreasing oil or salt concentration, encapsulating and controlling release of valuable components. In this study, it was aimed to formulate stable double emulsions to be used in food systems. W1/O ratios of primary emulsions, stabilized by polyglycerol polyricinoleate (PGPR), were designed as 2:8 and 4:6, and (W1/O)/W2 ratios of the double emulsions were used as 2:8 and 4:6. W/O/W phase ratios, homogenization methods applied to primary emulsion (high-speed homogenization, ultrasonic homogenization), and emulsifier types used in W2 phase [sodium caseinate (SC), xanthan gum, lecithin-whey protein concentrate] were used as independent variables. Particle size and distributions, stability, encapsulation efficiency (EE), rheological properties, long-term stability, and morphological properties of the double emulsions were investigated.

The double emulsions prepared with SC and (W1/O)/W2 ratio of 4:6, were found to have the higher stability values, higher apparent viscosity, and lower particle size. High-speed homogenization applied to primary emulsion reduced particle size of the double emulsion and increased apparent viscosity, but did not affect stability and EE of the double emulsions, significantly.  相似文献   
84.
In this study, it was aimed to investigate octavinyl‐polyhedral oligomeric silsesquioxane (OV‐POSS) incorporation into natural rubber (NR)/butadiene rubber (BR) elastomer blends as a potential compatibilizer. The effects of OV‐POSS loading levels on the thermal, mechanical, morphological, and dynamic‐mechanical properties of elastomer blends were explored. Fourier‐Transform Infrared Spectrometer (FTIR), Temperature Scanning Stress Relaxation (TSSR), and Differential Scanning Calorimetry (DSC) results revealed the conceivable effect of OV‐POSS nanoparticles in the vulcanization through reacting with sulfur and/or elastomers. Scanning Electron Microscope (SEM), X‐Ray Diffraction (XRD), and tensile test measurements supported the improvement of mechanical properties due to homogeneous dispersion at low loading levels. On the other hand, high amount of OV‐POSS incorporation (7 and 10 phr) resulted in a decrease in mechanical properties, owing to the agglomeration of nanoparticles. According to contact angle and Dynamic mechanical analysis (DMA) results, it could be concluded that OV‐POSS nanoparticles were localized at the interface of the elastomers and enabled the compatibilization of immiscible NR/BR blends.  相似文献   
85.
The use of two dibenzo[a,c]phenazine derivatives, 10,13‐bis(2,3‐dihydrothieno[3,4‐b][1,4]dioxin‐5‐yl)dibenzo[a,c]phenazine and 10,13‐bis(4‐hexylthiophen‐2‐yl)dibenzo[a,c]phenazine are reported as photosensitizers for diaryliodonium salt photoinitiators. Novel dyes based on the dibenzo[a,c]phenazine skeleton are shown to be efficient in carrying out the cationic photopolymerizations. Representative examples of different types of monomers including epoxide, and vinyl monomers are polymerized in the presence of the photosensitizers and diphenyliodonium hexafluorophosphate (Ph2I+PF). Polymerizations are initiated at room temperature using long wavelength UV and visible light, and monitored by optical pyrometry. The photopolymerization of an epoxide monomer via solar irradiation is also demonstrated. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011  相似文献   
86.
Kose MM  Yesilbag G  Sanyal A 《Organic letters》2008,10(12):2353-2356
Segment block dendrimers consisting of polyester and polyaryl ether dendrons were synthesized using reagent free Diels-Alder cycloaddition reactions. Three generations of furan functionalized polyaryl ether dendrons were reacted with maleimide functionalized polyester dendrons of the same generation to obtain segment block dendrimers in good yields. The thermoreversible nature of these macromolecules was investigated by subjecting them to elevated temperatures in the presence of anthracene as a scavenger diene.  相似文献   
87.
In this paper, we establish some new inequalities of Hermite-Hadamard type whose derivatives in absolute value are s-convex in the second sense. Finally some applications to special means of positive real numbers are given.  相似文献   
88.
Mathematical Programming - In this paper, we study the strength of Chvátal–Gomory (CG) cuts and more generally aggregation cuts for packing and covering integer programs (IPs)....  相似文献   
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