Multi-Component Diffusion Coefficients in Nitrogen Plasma Under Thermal Equilibrium and Non-equilibrium Conditions

Multi-component diffusion coefficients are calculated for a seven species model of nitrogen plasma under thermal non-equilibrium following the first order perturbation technique of Chapman and Enskog. Binary, thermal, thermal ambipolar, general and general ambipolar diffusion coefficients are presented over electron temperatures ranging from 300 to 50,000 K and thermal non-equilibrium parameter (Te/Th) ranging from 1 to 5. Considering large volume of data, binary, general and general ambipolar diffusion coefficients are presented only for atmospheric pressure. Thermal and thermal ambipolar diffusion coefficients are presented for pressures ranging from 0.1 to 2 atm. The results are compared with published experimental and theoretical data. Necessary electronic levels, associated transition data and collision integrals are collected from recent literature. Details of behaviour of each of the coefficients are presented.     

The Role of Functional Moieties on Carbon Nanotube Surfaces in Solar Energy Conversion

An easily dispersible multiwalled carbon nanotube (MWCNT) derivative is prepared, and provides a platform for the synthesis of the phenyl butyric acid methyl ester (PCBM) analog. The carbene addition reaction of MWCNTs makes derivatives that are less soluble in organic solvents; by exploiting this differential solubility, PCBM analogs can be separated from the unreacted functionalized MWCNTs. Our experimental evidences indicate that it is the unique properties of the butyric acid methyl ester moiety that makes the acceptor material perform better in organic photovoltaics (OPVs). Studying the combination of the butyric acid methyl ester moiety and the deagglomerated functionalized MWCNT structures provides us an insight into nanoscale charge transfer and transportation inside the donor–acceptor domain. It is demonstrated that a strong structure–property relationship exists for the functionalized MWCNTs, which enables us to correlate the functionality on the carbon nanostructures with performance in OPVs.     

Solvent effect of aqueous media on properties of glycine: Significance of specific and bulk solvent effects,and geometry optimization in aqueous media

Geometries of the normal (N) and zwitterionic (Z) forms of glycine (gly) and their complexes gly.(H₂O)_n, n = 0–2, were fully optimized in gas phase and aqueous media, and transition states located between the corresponding N and Z forms. The geometry was also optimized and vibrational spectra calculated for the gly.(H₂O)₃ complex of Z glycine. Density functional theory at the B3LYP/AUG‐cc‐pVDZ level was employed for the geometry optimization calculations in gas phase and aqueous media while single point energy calculations were performed at the MP2/AUG‐cc‐pVDZ level in each case. Solvation in bulk water was treated using the polarizable continuum model (PCM). Zero‐point energy correction to total energy and thermal energy correction to enthalpy were obtained at the B3LYP/AUG‐cc‐pVDZ level of theory in both gas phase and bulk aqueous media and these corrections were also considered to be valid for the corresponding single point energy calculations performed at the MP2/AUG‐cc‐pVDZ level of theory. When geometries of the complexes of glycine with water molecules are optimized in aqueous media, the calculated properties are found to be appreciably modified with respect to those obtained by gas phase geometry optimization followed by solvation in aqueous media. For several vibrational frequencies, the agreement between the calculated and experimentally observed results is improved appreciably when both the specific and bulk solvent effects are considered in combination with full geometry optimization in aqueous media. For certain vibrational frequencies, mode assignments have also been modified. © 2007 Wiley Periodicals, Inc. Int J Quantum Chem, 2008     

One-pot, Simple, and Convenient Synthesis of 2-Thioxo-2,3-dihydroquinazolin-4(1 H )-ones

A simple and convenient method for the synthesis of diverse 2-thioxo-2,3-dihydroquinazolin-4(1H)-ones was developed as one-pot reaction of anthranilic acid esters, primary amines, and bis(benzotriazolyl)methanethione in presence of the amidine base DBU.     

One-pot,Simple, and Convenient Synthesis of 2-Thioxo-2,3-dihydroquinazolin-4(1<Emphasis Type="Italic">H</Emphasis>)-ones

Summary. A simple and convenient method for the synthesis of diverse 2-thioxo-2,3-dihydroquinazolin-4(1H)-ones was developed as one-pot reaction of anthranilic acid esters, primary amines, and bis(benzotriazolyl)methanethione in presence of the amidine base DBU.     

Emergence of Visible-Light Water Oxidation Upon Hexaniobate-Ligand Entrapment of Quantum-Confined Copper-Oxide Cores

The formation of small 1 to 3 nm organic-ligand free metal-oxide nanocrystals (NCs) is essential to utilization of their attractive size-dependent properties in electronic devices and catalysis. We now report that hexaniobate cluster-anions, [Nb₆O₁₉]⁸⁻, can arrest the growth of metal-oxide NCs and stabilize them as water-soluble complexes. This is exemplified by formation of hexaniobate-complexed 2.4-nm monoclinic-phase CuO NCs ( 1 ), whose ca. 350 Cu-atom cores feature quantum-confinement effects that impart an unprecedented ability to catalyze visible-light water oxidation with no added photosensitizers or applied potentials, and at rates exceeding those of hematite NCs. The findings point to polyoxoniobate-ligand entrapment as a potentially general method for harnessing the size-dependent properties of very small semiconductor NCs as the cores of versatile, entirely-inorganic complexes.     

Temperature-induced phase separation in pseudoternary mixtures of Triton X-100–butanol–kerosene–water

The transparent Winsor IV domain in the phase diagram of the mixtures of emulsifier (Triton X-100 and butanol), oil (kerosene), and water is found to be 34% of the total phase diagram in presence of emulsifier with surfactant:cosurfactant::1:1, and is water dominant. Increase in cosurfactant/surfactant ratio inverts the Winsor IV domain to become oil rich. The plot of conductance of the microemulsions prepared by substituting water by brine against water content depicts the existence of three distinct phases like oil-in-water, bicontinuous, and water-in-oil microemulsion in the phase diagram. The phase contrast micrographs of the mixtures of different compositions in these three different phases reveal the existence of microdroplets of oil dispersed in water and water dispersed in oil. Further, the dynamic light scattering studies of these solutions reveal an inhomogeneity in the size distribution of the droplets. A temperature-induced clouding in the microemulsion domain leading to phase separation has been observed. Additives like glucose, sucrose, and sodium chloride decrease the cloud point (CP), while addition of ammonium thiocyanate increases it. A quantitative relationship of the clouding temperature with the composition of the microemulsion has been established. With increase in oil and emulsifier, the cloud point of the microemulsion increases. The separated phases after the clouding have been used for preconcentration of water-soluble metal ions as well as oil-soluble dyes. The turbid systems on heating led to separation into three isotropic phases which are found to be stable at ambient temperature. The stability of these phases is ascribed to the formation of stable microemulsions by mass transfer from one phase to other.     

Measurement of linear attenuation coefficients of normal and malignant breast tissues using synchrotron radiation

The linear attenuation coefficients of normal and malignant breast tissues have been measured in the energy range of 8–18 keV using Indus‐2 synchrotron source. The intensity of the incident as well as transmitted X‐ray photons in normal and malignant breast tissues is measured with AXUV 100GX silicon photodiode detector. Using these intensities, the linear attenuation coefficients of normal and malignant breast tissues have been measured. The measured linear attenuation coefficient values of cancer tissue are found to be higher than that of normal tissue throughout measured energy region. Copyright © 2016 John Wiley & Sons, Ltd.     

Arens regularity of projective tensor products

For completely contractive Banach algebras A and B (respectively operator algebras A and B), the necessary and sufficient conditions for the operator space projective tensor product \({A\widehat{\otimes}B}\) (respectively the Haagerup tensor product \({A\otimes^{h}B}\)) to be Arens regular are obtained. Using the non-commutative Grothendieck inequality, we show that, for C*-algebras A and B, \({A\otimes^{\gamma} B}\) is Arens regular if \({A\widehat{\otimes}B}\) and \({A\widehat{\otimes}B^{op}}\) are Arens regular whereas \({A\widehat{\otimes}B}\) is Arens regular if and only if \({A\otimes^{h}B}\) and \({B\otimes^{h}A}\) are, where \({\otimes^h}\), \({\otimes^{\gamma}}\), and \({\widehat{\otimes}}\) are the Haagerup, the Banach space projective tensor norm, and the operator space projective tensor norm, respectively.     

Use of enantiomerically pure 7-azabicyclo[2.2.1]heptan-2-ol as a chiral template for the synthesis of aminocyclitols

Using enantiopure 7-azabicyclo[2.2.1]heptane-2-ol, the synthesis of cis- as well as trans-2-aminocyclohexanols, dihydroconduramine E-1, and ent-conduramine F-1 has been described.