807 research outputs found

    Cooperative effects in surfactant adsorption layers at water/alkane interfaces

    No full text
    In the present work, the properties of dodecyl dimethyl phosphine oxide (C12DMPO) at the water/decane interface are studied and compared with those obtained earlier at the interface to hexane. To simulate the interfacial behavior, a two-component thermodynamic model is proposed, which combines the equation of state and Frumkin isotherm for decane with the reorientation model involving the intrinsic compressibility for the surfactant. In this approach, the surface activity of decane is governed by its interaction with C12DMPO. The theory predicts the influence of decane on the decrease of the surface tension at a very low surfactant concentration for realistic values of the ratio of the adsorbed amounts of decane and surfactant. The surfactantrsquo;s distribution coefficient between the aqueous and decane phases is determined. Two types of adsorption systems were used: a decane drop immersed into the C12DMPO aqueous solution, and a water drop immersed into the C12DMPO solution in decane. To determine the distribution coefficient, a method based on the analysis of the transfer of C12DMPO between water and decane is also employed

    Concurrent papillary thyroid cancer and parathyroid adenoma as a rare condition: A case report

    Get PDF
    Although the pathological relationship between parathyroid and thyroid diseases is common, an association between parathyroid adenoma and thyroid cancer is rare. Concomitant thyroid cancer in patients with primary hyperparathyroidism (pHPT) has been reported at varying frequencies. WE present here a 23-year-old man who had papillary thyroid carcinoma in the right thyroid lobe and a parathyroid adenoma in the left thyroid lobe, which were confirmed surgically. Copyright © 2012 Via Medica

    Comparison of technetium-99m IgG with technetium-99m red blood cells labeling in cardiac blood-pool scintigraphy: A preliminary study

    Get PDF
    This first clinical prospective study was conducted to use of technetium-99m immunoglobulin G (99mTc-IgG) as compared with autologous 99mTc-red blood cells (RBC) in gated blood pool ventriculography. We studied 12 patients who referred to us for a possible diagnosis of liver hemangioma or infection. Six patients underwent gated planar blood pool (GPBP) acquisition using 99mTc-RBC and 6 GPBP acquisition using 99mTc-IgG. The use of 99mTc-IgG in cardiac blood pool studies provided comparable images to 99mTc-RBC. In conclusion, 99mTc-IgG, which is readily available and needs only a single injection, may be an attractive alternative to 99mTc-RBC for the estimation of various cardiac function parameters like left ventricular function

    Efficient out-coupling of high-purity single photons from a coherent quantum dot in a photonic-crystal cavity

    Get PDF
    We demonstrate a single-photon collection efficiency of (44.3±2.1)%(44.3\pm2.1)\% from a quantum dot in a low-Q mode of a photonic-crystal cavity with a single-photon purity of g(2)(0)=(4±5)%g^{(2)}(0)=(4\pm5)\% recorded above the saturation power. The high efficiency is directly confirmed by detecting up to 962±46962\pm46 kilocounts per second on a single-photon detector on another quantum dot coupled to the cavity mode. The high collection efficiency is found to be broadband, as is explained by detailed numerical simulations. Cavity-enhanced efficient excitation of quantum dots is obtained through phonon-mediated excitation and under these conditions, single-photon indistinguishability measurements reveal long coherence times reaching 0.77±0.190.77\pm0.19 ns in a weak-excitation regime. Our work demonstrates that photonic crystals provide a very promising platform for highly integrated generation of coherent single photons including the efficient out-coupling of the photons from the photonic chip.Comment: 13 pages, 8 figures, submitte

    Grazing Effects on Some Soil Characteristics in Lar Rangelands

    Get PDF
    Heavy grazing pressures jeopardise the sustainability of the ecosystem by reducing soil fertility (Dormaar et al., 1998). Different results have been reported of grazing intensities on soil chemical properties, which stem from climate, soil, vegetation, management and kind of animal (Dormaar et al., 1998; Javadi, 2003; Sanadgool, 2002)
    corecore