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A study was conducted on the radio frequency power dependence of large area YBCO thin films on LaAlO3 substrates. A coplanar waveguide resonator method was employed in determining the changes of inductance and loss vs circulating microwave currents. Correlations were observed between the radio frequency power dependence and penetration depth, crystal structures and other film properties.

We propose a method for the determination of boron in aliphatic and aromatic trifluoroborates (including perfluorinated ones), ethers, and organoboron compounds containing dioxoborolane fragments, pyridine, and pyrazole rings, and triple bonds. The substances were decomposed by the oxygen flask combustion method. Boron was determined on an Agilent 4100 microwave plasma-atomic emission spectrometer. A number of organic compounds were analyzed, and the mass fraction of boron was determined with an error less than [+ or -]0.3 abs. %. Keywords: boron-containing organic compounds, sample preparation, microwave plasma atomic emission spectrometry, Various boron compounds are used as dopants in metallurgy, for the preparation of corrosion- and heat-resistant alloys, in glass making, production of boron plastics, luminophores, semiconductor materials, and propellent fuels. [...]

The potential energy curves of the low-lying doublet electronic states in the representation [sup.2s+1][Λ.sup.(+/-)] of the SrF molecule have been investigated by using the complete active space self-consistent field with multireference configuration interaction and multireference Rayleigh-Schrodinger perturbation theory methods. The harmonic frequency, [ω.sub.e]; the internuclear distance, [R.sub.e]; the dipole moment; and the electronic energy with respect to the ground state, [T.sub.e], have been calculated for the considered electronic states. The eigenvalues, [E.sub.v]; the rotational constants, [B.sub.v]; and the abscissas of the turning points, [R.sub.min] and [R.sub.max], have been investigated using the canonical functions approach. The comparison between the values of the present work and those available in the literature for several electronic states shows very good agreement. Nine new electronic states have been investigated here for the first time. PACS Nos.: 31.15.Ar, 31.25.Nj, 31.50.Df, 33.20.Vq. Les courbes d'energie potentielle des etats electroniques de basse energie dans la representation [sup.2s+1][Λ.sup.(+/-)] de la molecule de SrF sont etudiees ici a l'aide de la methode du champ auto-coherent de l'espace actif complet, additionnee de l'interaction de configurations multi reference et de la theorie des perturbations de Rayleigh-Schrodinger multi reference. Nous calculons pour les etats electroniques vises, la frequence harmonique, [ω.sub.e], la distance internucleaire, [R.sub.e], le moment dipolaire et l'energie electronique, [T.sub.e], mesuree par rapport au fondamental. Dans l'approche des fonctions canoniques, nous etudions les valeurs propres, [E.sub.v], les constantes rotationnelles, [B.sub.v], etles abscisses des points de retour, [R.sub.min] et [R.sub.max]. Nous observons un tres bon accord entre nos valeurs et celles deja publiees dans la litterature. Neuf nouveaux etats electroniques sont ici etudies pour la premiere fois. [Traduit par la Redaction], 1. Introduction The alkaline earth monohalide molecules (MX) have received considerable attention [1-4]. The bonding in these molecules is almost entirely ionic so their electronic structure can be pictured as [...]

The potential energy curves of the low-lying electronic states of the LaH molecule are reported via the CASSCF method with multireference calculations (single and double excitations with Davidson corrections). Twenty-four low-lying electronic states of the LaH molecule in the representation [sup.2s+1][Λ.sup.(+/-)] below 20 000 [cm.sup.-1] were investigated along with five lower electronic states in the Ω representation. The harmonic frequency [ω.sub.e], the equilibrium internuclear distance [R.sub.e], the rotational constants [B.sub.e], and the electronic energy with respect to the ground state [T.sub.e] were calculated for these states. Twelve new electronic states are investigated in the present work for the first time that have not yet been observed experimentally. Using the canonical functions approach, the eigenvalues [E.sub.v], the rotational constants [B.sub.v], the centrifugal distortion constants [D.sub.v], and the abscissas of the turning points [R.sub.min] and [R.sub.max] were calculated for the investigated electronic states up to vibrational level v = 43. Key words: ab initio calculation, spectroscopic constants, potential energy curves, rovibrational calculation. Les courbes d'energie potentielle des bas etats excites de la molecule LaH ont ete tracees a l'aide la methode CASSCF et de calculs multireferentiels (excitations simples et doubles et corrections de Davidson). Vingt-quatre bas etats electroniques de la molecule LaH dans la representation [sup.2s+1][Λ.sup.(+/-)] en dessous de 20 000 [cm.sup.-1] et cinq etats electroniques les plus bas dans la representation Ω ont ete etudies. La frequence harmonique [ω.sub.e], la distance internucleaire d'equilibre [R.sub.e], les constantes de rotation [B.sub.e] et l'energie electronique liees a l'etat fondamental [T.sub.e] ont ete calculees pour ces etats. Douze nouveaux etats electroniques, encore jamais observes experimentalement, sont pour la premiere fois analyses dans la presente etude. A l'aide de l'approche des fonctions canoniques, les valeurs propres [E.sub.v], les constantes de rotation [B.sub.v], les constantes de distorsion centrifuge [D.sub.v] et les abscisses des points d'inflexion [R.sub.min] et [R.sub.max] ont ete calculees pour les etats electroniques etudies jusqu'au niveau vibrationnel v = 43. [Traduit par la Redaction] Mots-cles: calcul ab initio, constantes spectroscopiques, courbes d'energie potentielle, calcul ro-vibrationnel., Introduction The transition metal monohydrides and monohalides have been extensively studied over several decades because they are of considerable interest in various fields such as astrophysics, catalytic chemistry, high-temperature chemistry, [...]

Changes in the amount of conjugation in the biphenyl system upon torsion have been investigated with quantum chemistry computations. For the unsubstituted biphenyl and its radical cation, the change in the energy for the first electronic transition as determined from time-dependent density functional theory, specifically TD-B3LYP, upon an imposed change in torsion angle appears to provide a good general measure of the delocalization of the π-electrons. Upon substitution, though, a relationship could not be established between the excitation energy and the twist across the C-C bond connecting the two phenyl rings. In contrast, the π-interaction energy, i.e., the π-π interaction across the central C-C bond, determined from a natural bond orbital analysis, provides a uniform description of conjugation in the electronically different systems, for an imposed twist as well as upon substitution. Substituent effects are found to be larger and more varied for the biphenyl radical cations. Of particular interest is the introduction of the oxidizable substituents OCH3 (methoxyl) and SCH3 (methylthio), as this leads to the smallest changes in torsion angle in the biphenyl unit upon removal of an electron from the molecule. The findings of this work could ultimately prove useful for the rational design of conductive polymer materials. Key words: biphenyl, conjugation, substituent effect, electronic excitation, π-interaction energy. Des calculs de chimie quantique, utilisant la theeorie de la fonctionnelle de la densite dependante du temps, specifiquement TD-B3LYP, ont ete effectues afin d'evaluer les variations de conjugaison dans le systeme biphenyle en fonction de sa torsion. Pour le biphenyle non substitue et son cation radicalaire, l'energie correspondant a la premiere transition electronique suivant la torsion imposee semble fournir une mesure adequate de la delocalisation des electrons π. Par contre, pour les biphenyles substitues, il n'est pas possible d'etablir une relation entre l'energie d'excitation et l'angle de torsion au niveau de la liaison C-C qui relie les deux phenyles. Toutefois, l'energie d'interaction π, c'est-a-dire l'interaction π-π le long de la liaison C-C centrale, telle que determinee par une analyse des orbitales naturelles de liaison, fournit une description uniforme de la conjugaison dans des systemes electroniquement differents, que ce soit par torsion imposee ou par substitution. De plus, les effets de substitution sur la conjugaison sont plus prononces et plus varies pour les cations radicalaires des biphenyles. Il est particulierement interessant de noter que l'introduction de substituants oxydables, tels que OCH3 (methoxyle) ou SCH3 (methylthio), entraine la plus faible variation de l'angle de torsion de l'unite biphenyle lorsqu'elle perd un electron. Les resultats de ces travaux pourraient eeventuellement aider a mieux predire les proprietes de nouveaux materiaux a base de polymeres conducteurs. Mots-cles: biphenyle, conjugaison, effet de substituant, excitation electronique, eenergie d'interaction π., Introduction Conjugation, the delocalization of π-electrons, is related to important chemical and physical phenomena, such as aromaticity, spectral shifts, and electronic conductivity. Conductive polymers, especially oligo- and poly-paraphenylenes, have found [...]

The theoretical electronic structure of the LuF molecule is investigated, using the Complete Active-Space Self- Consistent Field CASSCF and the MultiReference Configuration Interaction MRCI methods. These methods are performed for 26 electronic states in the representation [sup.2s+1][[DELTA[].sup.(+/-)], neglecting spin-orbit effects. Spectroscopic constants including the harmonic vibrational wave number [ω.sub.e]([cm.sup.-1]), the relative electronic energy [T.sub.e]([cm.sup.-1]) referred to the ground state and the equilibrium internuclear distance [R.sub.e] (Å) are predicted for all the singlet and triplet electronic states situated below 50 000 [cm.sup.-1]. Calculated potential energy curves are also reported. PACS No: 31.15.Ar Nous avons fait une etude theorique de la structure electronique de la molecule LuF en utlisant la methode du champ self-consistent dans un espace actif complet d'eetats (CASSCF) et la methode d'interaction multi-reference entre configurations. Ces methodes ont ete utilises pour 26 etats electroniques dans la representation [sup.2s+1][Λ.sup.(+/-)] (negligeant les effets spin-orbite). Nous presenteras les courbes d'energie calculees. Nous pouvons predire les constantes spectroscopiques, incluant le nombre d'onde de vibration harmonique [ω.sub.e] ([cm.sup.-1]), l'energie electronique relative [T.sub.e] par rapport au fondamental et la distance d'equilibre internucleeaire [R.sub.e] (Å) et ce pour tous les etats singlets et triplets situes sous les 50 000 [cm.sup.-1]. [Traduit par la Redaction], 1. Introduction The quantum chemistry studies of molecules containing lanthanide elements such lutetium have received significant interest in many areas [1-17]. These kinds of molecules, which are produced in the [...]

Objective: We hypothesized that low serum selenium was associated with anemia in humans. Subjects: A total of 2092 adults aged 65 and older, in the third National Nutrition Examination Survey, Phase 2 (1991-1994) (NHANES III). Methods: Examination of the relationship between serum selenium and hematological indices in NHANES III. Results: Anemia, defined by World Health Organization criteria, was present in 12.9%. Mean serum selenium among non-anemic and anemic adults was 1.60 and 1.51 [micro][moll.sup.-1] (P = 0.0003). The prevalence of anemia among adults in the lowest to highest quartiles of serum selenium was 18.3, 9.5, 9.7 and 6.9%, respectively (P = 0.0005). The proportion of adults in the lowest quartile of selenium among those who were non-anemic or who had anemia due to nutritional causes, chronic inflammation, renal disease or unexplained anemia was 9.9, 27.5, 17.5, 24.0 and 15.4%, respectively. An increase in [log.sub.e] selenium was associated with a reduced risk of anemia (odds ratio per one standard deviation increase 0.75, 95% confidence interval 0.58-0.97, P = 0.03), adjusting for age, race, education, body mass index and chronic diseases. Conclusion: Low serum selenium is independently associated with anemia among older men and women in the United States. European Journal of Clinical Nutrition (2009) 63, 93-99; doi:10.1038/sj.ejcn.1602889; published online 5 September 2007 Keywords: aging; anemia; inflammation; hemoglobin; selenium, Introduction Anemia is common in older adults, and the prevalence of anemia increases with advancing age (Beghe et al., 2004; Woodman et al., 2005). Among older adults, anemia has been [...]

Abstract: Cu-[(pyridine).sub.n] (n = 1, 2) complexes are prepared in a pulsed laser ablation cluster source and identified using laser photoionization time-of-flight mass spectrometry. High-resolution electron spectra of these complexes [...]

Abstract The effect of Nigella sativa (NS) L. oil (blackseed oil) on the fibrinolytic system of the human umbilical vein (HUV) and human uterine arterial (HUA) endothelial cells (ECs) in [...]

Even when there seems to be consensus that school change is needed and even when dedicated and well-intentioned people are trying to bring it about, issues and problems arise that [...]

Byline: G. Paul, P. Sood, B. Paul, S. Puri Antihistamines are easily available over-the-counter medications, which are frequently involved in overdoses. The usual course is accompanied by the anticholinergic effects [...]