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71.
72.
We examine using Monte Carlo simulations, photon transport in optically ‘thin’ slabs whose thickness L is only a few times the transport mean free path l*, with particles of different scattering anisotropies. The confined geometry causes an auto-selection of only photons with
looping paths to remain within the slab. The results of the Monte Carlo simulations are borne out by our analytical treatment
that incorporates directional persistence by the use of the Ornstein-Uhlenbeck process, which interpolates between the short
time ballistic and long time diffusive regimes. 相似文献
73.
Obliquely propagating altra-low-frequency dust-electromagnetic waves in a self-gravitating, warm, magnetized, two fluid dusty
plasma system have been investigated. Two special cases, namely, dust-Alfvén mode propagating parallel to the external magnetic
field and dustmagnetosonic mode propagating perpendicular to the external magnetic field have also been considered. It has
been shown that effects of self-gravitational field, dust fluid temperature, and obliqueness significantly modify the dispersion
properties of these ultra-low-frequency dust-electromagnetic modes. It is also found that in parallel propagating dust-Alfvén
mode these effects play no role, but in obliquely propagating dust-Alfvén mode or perpendicular propagating dust-magnetosonic
mode the effect of self-gravitational field plays destabilizing role whereas the effect of dust/ion fluid temperature plays
stabilizing role. 相似文献
74.
Lisa Diab Jean‐Claude Daran Maryse Gouygou Eric Manoury Martine Urrutigoïty 《Acta Crystallographica. Section C, Structural Chemistry》2008,64(1):m43-m45
Two enantiopure palladium(II) complexes, viz. [1,1′‐(butane‐1,3‐diyl)‐3,3′,4,4′‐tetramethyl‐5,5′‐diphenyl‐2,2′‐biphosphole]dichloridopalladium(II) dichloromethane solvate [systematic name: dichlorido(1,2,5,10,11‐pentamethyl‐3,9‐diphenylperhydrodicyclopenta[a,c][1,4]diphosphepine‐κ2P,P′)palladium(II) dichloromethane solvate], [PdCl2(C28H30P2)]·CH2Cl2, have been synthesized from stereodynamic diphosphines derived from 2,2′‐biphosphole through a metal kinetic dynamic resolution. In both structures, the coordination around the metal atom is square planar, with a cis arrangement of the ligands that drastically reduces the dihedral angle between the two phosphole rings compared with the free ligand. The structural determination of both enantiomers unambiguously establishes the absolute configuration of both central and axial elements of chirality of the 2,2′‐biphosphole framework and indicates that the original carbon chirality of the backbone controls the chiralities of the 2,2′‐biphosphole framework. 相似文献
75.
76.
77.
A.M. Ahmed N.M. Megahid M.M. Wakkad A.K. Diab 《Journal of Physics and Chemistry of Solids》2005,66(7):1274-1280
Chalcogenide bulk alloys of Agx (As0.4Se0.6) 100−x (x=5, 7.5, 10, 12.5, 15 and 17.5) system were prepared by the conventional melt-quench technique. The d.c. electrical conductivity (σ) and thermoelectric power (TEP) measurements were carried out in the temperature range from 83 to 373 K and from 253 to 373 K, respectively. Variations of both σ and TEP with ambient temperature proved the p-type semiconducting behaviour of these materials. The current density-electric field characteristics were found to be linear. The activation energies, calculated from both the electrical conductivity Eσ and thermoelectric power Es, were found to be dependent on composition. 相似文献
78.
79.
Evin AHN SADIK Hamdi Melih SARAOLU lke GÜROL Mehmet Ali EBEOLU Fatma Emel KOAK 《Turkish Journal of Chemistry》2020,44(5):1293
Determining the blood glucose level is important for the prevention and treatment of diabetes mellitus. We developed a sensor system using Quartz Crystal Microbalance (QCM) to determine the blood glucose level from human blood serum. This study consists of two experimental stages: artificial glucose/pure water solution tests and human blood serum tests. In the first stage of the study, the QCM sensor with the highest performance was identified using artificial glucose solution concentrations. In the second stage of the study, human blood serum measurements were performed using QCM to determine blood glucose levels. QCM sensors were coated with phthalocyanines (Pcs) by jet spray method. The blood glucose values of 96 volunteers, which ranged from 71 mg/dL to 329 mg/dL, were recorded. As a result of the study, human glucose values were determined with an average error of 3.25%. 相似文献
80.
A study of environmental radioactivity along the northwestern coast of Egypt was performed by the Central Laboratory for Environmental Radioactivity Measurements Inter-comparison and Training within the framework of the research project: Radiological Studies/Measurements of Natural and Man-made Radionuclides in the Environment. The present paper contains important conclusions, correlations and interpretations of the environmental measurements. The samples collection and measurements were conducted according to the Egyptian Atomic Energy Authority monitoring plan for locations along the northwestern coast of Egypt and its main tributaries of interest. The specific activities of 226Ra (238U series), 228Ra (232Th series), 40K and 137Cs (Bq/kg dry weight) were measured using gamma-ray spectrometers based on hyper-pure germanium detectors. The absorbed radiation dose rates in air (nGy/h) due to natural radionuclides in shore sediment and radium equivalent activity index (Bq/kg) were calculated. The specific activity ratios of 228Ra/226Ra were calculated for evaluation of the geo-chemical behavior of these radionuclides. Samples textures and CaCO3 and total organic matter contents of sediments were also determined while the pH, major cations and anions such as Na+, K+, Ca++, Mg++and Cl?, SO4 – and HCO3, respectively were also determined in water samples. 相似文献