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111.
Pramod K. Shanavas S. Ansari Shahid H. Ali Javed 《Journal of Sol-Gel Science and Technology》2012,61(1):161-168
Nanodroplets can be considered as those nano/microemulsions in which the oil itself forms the active agent and the droplet
size ambits in the nanometer range. Eugenol is an anti-inflammatory agent and its nanodroplet gel (NDG) has immense potential
for topical use. Topical gels oblige some rheological characteristics to nail down the demands of proper application, stability
and storage. Thus, the purpose of our study was to comprehend the effect of eugenol on the sol–gel tranisition properties
of its NDGs. Towards this goal nanodroplets of eugenol were prepared and evaluated and the three selected nanodroplet formulations
with 5, 10 and 5% v/v eugenol were converted into topical gel formulation using 1% w/w Carbopol 940. The NDGs were characterized
using frequency sweep, creep recovery and thixotropy. All these tests pointed out that eugenol concentration has significant
effect on the sol–gel behavior of NDGs. The NDGs exhibited more viscous (sol) properties than elastic (gel) properties as
observed from the frequency sweep studies. The thixotropy of the NDGs was found to decrease with increase in eugenol concentration.
Efforts have been made to explain the study results using mechanistic approach. The outcomes of our research studies could
be of great use in future endeavors towards development of a topical NDG of eugenol with tailored sol–gel behavior. 相似文献
112.
113.
Mysore Srinivas Pramod Tao Yang Kanhaiya Pandey Massimo Giudici David Wilkowski 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2014,68(7):1-5
Injection locking is a well known and commonly used method for coherent light amplification. Usually injection locking is obtained on a single-mode laser injected by a single-frequency seeding beam. In this work we show that selective injection locking of a single-frequency may also be achieved on a multi-mode semiconductor laser injected by a multi-frequency seeding beam, if the slave laser provides sufficient frequency filtering. This selective injection locking condition depends critically on the frequency detuning between the free-running slave emission frequency and each injected frequency component. Stable selective injection locking to a set of three seeding components separated by 1.2 GHz is obtained. This system provides an amplification up to 37 dB of each component. This result suggests that, using distinct slave lasers for each frequency line, a set of mutually coherent high-power radiation modes can be tuned in the GHz frequency domain. 相似文献
114.
We propose a simple phenomenological model which is able to account for the various twist grain boundary (TGB) phases, including the recently discovered undulating twist grain boundary-C* (UTGBC*) phase. In the UTGBC* phase, the smectic C* (SmC*)-like blocks and the grain boundaries separating them undulate to form a two-dimensional square lattice perpendicular to the TGB helix axis. We treat the grain boundaries separating adjacent smectic blocks as interfaces with an anisotropic interfacial tension. At moderate chiral strengths we find a TGBA-TGBC-SmC* sequence. As the chiral strength is increased this goes to the sequence TGBA-UTGBC*-SmC*. Such sequences have been observed experimentally. 相似文献
115.
116.
Environmentally benign conditions have been developed for the synthesis of 2-amino-4-(2-oxo-2H-chromen-3-yl)thiophene-3-carbonitriles (3) starting from 3-acetyl-2H-chromen-2-one (1) through the intermediacy of 2-(1-(2-oxo-2H-chromen-3-yl)ethylidene)malononitrile (2) using the Knoevenagel condensation followed by the Gewald reaction. Alternatively, 3 could also be prepared in a one pot method by treating equimolar amounts of 1, malononitrile, and elemental sulfur. The merits of this preparation are mild reaction conditions, easy work-up procedure, and good yields. 相似文献
117.
Anderson NL Vedula RP Schultz PA Van Ginhoven RM Strachan A 《Physical review letters》2011,106(20):206402
We show that oxygen vacancies are not necessary for the formation of E' centers in amorphous SiO? and that a single O deficiency can lead to two charge traps. Employing molecular dynamics with a reactive potential and density functional theory, we generate an ensemble of stoichiometric and oxygen-deficient amorphous SiO? atomic structures and identify low-energy network defects. Three-coordinated Si atoms appear in several low-energy defects both in stoichiometric and O-deficient samples where, in addition to the neutral oxygen vacancy, they appear as isolated defects. 相似文献
118.
This Letter proposes a method to estimate phase derivatives of arbitrary order in digital holographic interferometry. Based on the desired order, the generalized complex-lag distribution is computed from the reconstructed interference field. Subsequently, the phase derivative is estimated by tracing the peak of the distribution. Simulation and experimental results are presented to validate the method's potential. 相似文献
119.
Bon Ki Ku Gregory J. Deye Pramod Kulkarni Paul A. Baron 《Journal of Electrostatics》2011,69(6):641-647
Recent studies have raised concerns over applicability of the conventional charging theories to non-spherical particles such as soot aggregates and single-walled carbon nanotube aerosols of complex shape and morphology. It is expected that the role of particle structure and shape on particle diffusion charging characteristics may be significant in the submicron size range for carbon nanotubes (CNTs) and nanofibers (CNFs). In this study, we report experimental data on equilibrium charging characteristics of high-aspect ratio aerosol particles such as CNFs and multi-walled CNTs (MWCNTs) when exposed to a bipolar ion atmosphere. A neutral fraction was measured, i.e., the fraction of particles carrying no electrical charge. A differential mobility analyzer (DMA) was used to classify aerosols, leaving a bipolar radioactive charger to infer the bipolar charging characteristics at different mobility diameters in the submicron size range. The measured neutral fractions for CNF aerosol particles were lower than the corresponding Boltzmann values by 24.4%, 42.0%, and 45.8% for mobility diameters of 400 nm, 600 nm, and 700 nm, respectively, while the neutral fractions for measured aerodynamic diameters of 221 nm, 242 nm, and 254 nm were much lower than those expected by Boltzmann charge distribution, by 43.8%, 63.1%, and 67.3%, respectively. Neutral fractions of spherical particles of polystyrene latex (PSL) and diethylhexyl sebacate (DEHS) particles, measured under identical experimental conditions and procedure, agreed well with the Boltzmann charge distribution. The measured neutral fractions for MWCNT aerosol particles were lower than the corresponding Boltzmann values by 22.3%–25.0% for mobility diameters in the size range from 279 nm to 594 nm. Charging-equivalent diameters of CNF particles correlated well with either mobility diameter or equal-area diameter, which were found to be larger than their mobility or equal-area diameters by up to a factor of 5 in the size range of 400 nm–700 nm, while those of MWCNT particles were larger than the corresponding diameters by a factor of 2 in the size range of 279 nm–594 nm. 相似文献
120.
Cu(acac)2 activates aryl boronic acids for the reaction with NH2-phenylurea without additional ligand and heating. The procedure is simple, general, ligand-free, milder than the palladium-catalyzed arylation, and avoids the use of toxic phosphine ligands. 相似文献