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171.
Pelin Pocan Esmanur Ilhan Mecit Halil Oztop 《Magnetic resonance in chemistry : MRC》2019,57(9):661-673
Confectionary gels are considered as composite gel systems composed of high amount of sugar and gelling agent such as gelatin or starch. d -Psicose is classified as a type of rare sugar, which is a C-3 epimer of fructose and has 70% of the sweetness of sucrose with a caloric value of 0.39 kcal/g. Utilization of d -psicose in food products is gaining particular interest due to its low caloric value. In this study, gelatin-based soft candies were formulated, and the effect of d -psicose substitution was explored on the quality of the products. For characterization of the soft candies, moisture content, water activity, color, hardness, and glass transition temperature of samples were investigated. X-ray diffraction analysis was also performed to explain the crystallization tendency of jelly candies. Results showed that, the softest sample with the highest moisture content and the smallest crystallization tendency was the sample that included the highest amount of d -psicose. Time domain (TD) NMR relaxometry experiments were also conducted on gel samples, and three distinct proton populations were observed in the relaxation spectrum for all formulations. Spin–lattice relaxation times obtained through monoexponential fitting (T1) were also obtained to explain some quality parameters. 相似文献
172.
173.
Yakan Hasan Cakmak Sukriye Kutuk Halil Yenigun Semiha Ozen Tevfik 《Research on Chemical Intermediates》2020,46(5):2767-2787
Research on Chemical Intermediates - We performed a series of novel benzamide compounds which were synthesized starting from 2,3-dimethoxybenzoic acid or 3-acetoxy-2-methylbenzoic acid and amine... 相似文献
174.
Dr. Genoa R. Warner Dr. Yogesh Somasundar Cindy Weng Mete H. Akin Prof. Dr. Alexander D. Ryabov Prof. Dr. Terrence J. Collins 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(34):7631-7637
Bis-sulfonamide bis-amide TAML activator [Fe{4-NO2C6H3-1,2-(NCOCMe2NSO2)2CHMe}]− ( 2 ) catalyzes oxidative degradation of the oxidation-resistant neonicotinoid insecticide, imidacloprid (IMI), by H2O2 at pH 7 and 25 °C, whereas the tetrakis-amide TAML [Fe{4-NO2C6H3-1,2-(NCOCMe2NCO)2CF2}]− ( 1 ), previously regarded as the most catalytically active TAML, is inactive under the same conditions. At ultra-low concentrations of both imidacloprid and 2 , 62 % of the insecticide was oxidized in 2 h, at which time the catalyst is inactivated; oxidation resumes on addition of a succeeding aliquot of 2 . Acetate and oxamate were detected by ion chromatography, suggesting deep oxidation of imidacloprid. Explored at concentrations [ 2 ]≥[IMI], the reaction kinetics revealed unusually low kinetic order in 2 (0.164±0.006), which is observed alongside the first order in imidacloprid and an ascending hyperbolic dependence in [H2O2]. Actual independence of the reaction rate on the catalyst concentration is accounted for in terms of a reversible noncovalent binding between a substrate and a catalyst, which usually results in substrate inhibition when [catalyst]≪[substrate] but explains the zero order in the catalyst when [ 2 ]>[IMI]. A plausible mechanism of the TAML-catalyzed oxidations of imidacloprid is briefly discussed. Similar zero-order catalysis is presented for the oxidation of 3-methyl-4-nitrophenol by H2O2, catalyzed by the TAML analogue of 1 without a NO2-group in the aromatic ring. 相似文献
175.
Mete Kaan Ekmekçi Mustafa İlhan Arzu Ege Mehmet Ayvacıklı 《Journal of fluorescence》2017,27(3):973-979
Undoped and different concentration Nd3+ doped SrNb2O6 powders with columbite structure were synthesized by molten salt process using a mixture of strontium nitrate and niobium (V) oxide and NaCl-KCl salt mixture as a flux under relatively low calcining temperature. X-ray diffraction analysis results indicated that SrNb2O6 phases found to be orthorhombic columbite single phase for undoped, 0.5 and 3 mol% Nd3+ doping concentrations. Phase composition of the powders was examined by SEM-EDS analyses. Radioluminescence properties of Nd3+ doped samples from UV to near-IR spectral region were studied. The emissions increased with the doping concentration of up to 3 mol%, and then decreased due to concentration quenching effect. There is a sharp emission peak around 880 nm associated with 4F5/2 → 4I9/2 transition in the Nd3+ ion between 300 and 1100 nm. The broad emission band intensity was observed from 400 to 650 nm where the peak intensities increased by increasing Nd3+ doping concentration. All the measurements were taken under the room temperature. 相似文献
176.
In this paper, the concept of lacunary equi-statistical convergence is introduced and it is shown that lacunary equi-statistical
convergence lies between lacunary statistical pointwise and lacunary statistical uniform convergence. Inclusion relations
between equi-statistical and lacunary equi-statistical convergence are investigated and it is proved that, under some conditions,
lacunary equi-statistical convergence and equi-statistical convergence are equivalent to each other. A Korovkin type approximation
theorem via lacunary equi-statistical convergence is proved. Moreover it is shown that our Korovkin type approximation theorem
is a non-trivial extension of some well-known Korovkin type approximation theorems. Finally the rates of lacunary equi-statistical
convergence by the help of modulus of continuity of positive linear operators are studied.
相似文献
177.
Halil Berberoglu Pedro S. Gomez Laurent Pilon 《Journal of Quantitative Spectroscopy & Radiative Transfer》2009,110(17):1879-1893
This paper reports experimental measurements of the radiation characteristics of green algae used for carbon dioxide fixation via photosynthesis. The generated biomass can be used to produce not only biofuels but also feed for animal and food supplements for human consumptions. Particular attention was paid to three widely used species namely Botryococcus braunii, Chlorella sp., and Chlorococcum littorale. Their extinction and absorption coefficients were obtained from normal–normal and normal–hemispherical transmittance measurements over the spectral range from 400 to 800 nm. Moreover, a polar nephelometer was used to measure the scattering phase function of the microorganisms at 632.8 nm. It was observed that for all strains, scattering dominates over absorption. The magnitudes of the extinction and scattering cross-section are functions of the size, shape, and chlorophyll content of each strain in a non-trivial manner. Absorption peaks at 435, 475, and 676 nm corresponding to chlorophyll a and chlorophyll b. The results can be used for scaling and optimization of CO2 fixation in ponds or photobioreactors as well as in the development of controlled ecological life support systems. 相似文献
178.
Propagation of circular and elliptical anomalous hollow beams in a turbulent atmosphere is investigated in detail. Based on the extended Huygens–Fresnel integral, analytical formulae for the average irradiance of circular and elliptical anomalous hollow beams propagating in a turbulent atmosphere are derived. The irradiance and spreading properties of circular and elliptical anomalous hollow beams in a turbulent atmosphere and in free space are studied numerically. It is found that circular and elliptical anomalous hollow beams at short propagation distance in turbulent atmosphere have similar propagation properties to those of free space, while at long propagation distance, circular and elliptical anomalous hollow beams eventually become circular Gaussian beams in a turbulent atmosphere, which is much different from their propagation properties in free space. The conversion from an anomalous hollow beam to a circular Gaussian beam becomes quicker and the beam spot spreads more rapidly for a larger structure constant, a shorter wavelength and a smaller waist size of the initial beam. 相似文献
179.
Propagation and coherence properties of higher order partially coherent dark hollow beams in turbulence 总被引:3,自引:1,他引:2
Halil Tanyer Eyyubolu 《Optics & Laser Technology》2008,40(1):156-166
We formulate and evaluate in terms of graphical outputs, source and receiver plane expressions, the complex degree of coherence, beam size variation and power in bucket performance for higher order partially coherent dark hollow beams propagating in turbulent atmosphere. Our formulation is able to cover square, rectangular, circular, elliptical geometries for dark hollow and flat-topped beams in one single expression. From the graphical outputs of the receiver plane, it is observed that higher order partially coherent dark hollow beams will initially develop an outer ring around a central lobe, but will eventually evolve towards a Gaussian shape as the propagation distance is extended. It is further observed that stronger turbulence levels and greater partial coherence have similar effects on beam profile. During propagation, modulus of complex degree of coherence of partially coherent dark hollow beams appears to rise above that of the source plane values, reaching as high as near unity. Beam size analysis shows that, among the types examined, (nearly) flat-topped beam experiences the least beam expansion. Power in bucket analysis indicates that lowest order square fully coherent dark beam offers the best power capturing. 相似文献
180.
Propagation of modified Bessel-Gaussian beams in turbulence 总被引:2,自引:0,他引:2
We investigate the propagation characteristics of modified Bessel-Gaussian beams traveling in a turbulent atmosphere. The source beam formulation comprises a Gaussian exponential and the summation of modified Bessel functions. Based on an extended Huygens–Fresnel principle, the receiver plane intensity is formulated and solved down to a double integral stage. Source beam illustrations show that modified Bessel-Gaussian beams, except the lowest order case, will have well-like shapes. Modified Bessel-Gaussian beams with summations will experience lobe slicing and will display more or less the same profile regardless of order content. After propagating in turbulent atmosphere, it is observed that a modified Bessel-Gaussian beam will transform into a Bessel-Gaussian beam. Furthermore it is seen that modified Bessel-Gaussian beams with different Bessel function combinations, but possessing nearly the same profile, will differentiate during propagation. Increasing turbulence strength is found to accelerate the beam transformation toward the eventual Gaussian shape. 相似文献