Studies of phosphazenes. 28. Reactions of pentachloro- and pentafluoro(triphenylphosphazenyl)cyclotriphosphazenes with sodium methoxide. Mechanistic aspects and their implications for nucleophilic displacement at a tetrahedral phosphorus(V) center

Abstract is not available.

Studies on crystalline complexes involving amino acids. V. The structure of L-serine-L-ascorbic acid

L-Serine-L-ascorbic acid, C3HTNOa. C6HsO6, a 1:1 complex between the amino acid serine and the vitamin ascorbic acid, crystallizes in the orthorhombic space group P2~2~2~ with four formula units in a cell of dimensions a = 5.335(3), b = 8.769(2), c = 25.782 (5) A. The structure was solved by direct methods and refined by full-matrix least squares to an R of 0.036 for 951 observed reflections. Both molecules are neutral in the structure. The conformation of the serine molecule is different from that observed in the crystal structures of L-serine, DL-serine and L-serine monohydrate. The enediol group in the ascorbic acid molecule is planar, whereas significant departures from planarity are observed in the lactone group. The conformation of this molecule is similar to that observed in arginine ascorbate. The unlike molecules aggregate into separate columns in the crystal structure. The columns are held together by hydrogen bonds. Among these, a pair of hydrogen bonds between the enediol group of ascorbic acid and the carboxylate group of serine provides a possible model for a specific interaction between ascorbic acid and a carboxylate ion.

Influence of Band Non-Parabolicity on Few Ballistic Properties of III-V Quantum Wire Field Effect Transistors Under Strong Inversion

A simplified yet analytical approach on few ballistic properties of III-V quantum wire transistor has been presented by considering the band non-parabolicity of the electrons in accordance with Kane's energy band model using the Bohr-Sommerfeld's technique. The confinement of the electrons in the vertical and lateral directions are modeled by an infinite triangular and square well potentials respectively, giving rise to a two dimensional electron confinement. It has been shown that the quantum gate capacitance, the drain currents and the channel conductance in such systems are oscillatory functions of the applied gate and drain voltages at the strong inversion regime. The formation of subbands due to the electrical and structural quantization leads to the discreetness in the characteristics of such 1D ballistic transistors. A comparison has also been sought out between the self-consistent solution of the Poisson's-Schrodinger's equations using numerical techniques and analytical results using Bohr-Sommerfeld's method. The results as derived in this paper for all the energy band models gets simplified to the well known results under certain limiting conditions which forms the mathematical compatibility of our generalized theoretical formalism.

Gurs: 'Stamps' from the concentration camp,q-v.

The designs are drawn in the miniature style of postage stamps and include mock postage prices. Presumably this method was inspired by the shortage of paper at the camp in Gurs, Southern France, where these works were done; but specially this format is also used to stress the irony of the content, especially in the trio of design marked "Liberte-Egalite-Fraternite", aside from one marked "Avion de Gurs", all others are labelled simply " Gurs ", at the bottom as if this were the country of origin of a postal system.

Plan U.S.R.R. Melitopol'skogo okruga Genicheskogo raiona poluostrova Chongar vymezhevannogo v poriadke chastichnogo izmeneniia ustroistva kolfonda s ustroistvom poselkov, razbivkoiu na polia sevooborota, gony soglasno nakazu N.K.Z dnia 1927, n 52-2825. Izmerenie v nature proizvedeno i plan etot sostovlen X. partieiu po ustroistvu kolfondov

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Skhematicheskii plan uchastkov pereselencheskogo fonda v Krymu

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Sostoianie posevov v raionakh evreiskogo zemledeliia na 15-oe iiunia 1927 goda

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Meditsinskie uchastki v evreiskikh koloniiakh Khersonskogo u Kr.Rozhskogo raionov

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Vykopirovka plana Melitopol'skogo okruga Genicheskovo raiona poluostrova Chongar otgranichennogo v poriadke ustroistva Kolfonda s obrazovaniem posëlkov i rozbivkoiu na polia sevooborota goni, sogliasno plana zemleustraitelnykh rabot po 1925-1926 gg.; plan sostavlen 9 partiei po ustroistvu kolfonda

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Proekt otvoda zemli "Komzetu" po Sary-Bulatskoi dachi razverstaniia Evpatoriiskogo raiona v 1930 godu

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Vykopirovka iz obshchego plana Biiuk-Onlarskoi dachi razverstaniia na uchastok, otvedennyi KOMZET-u pri der. Lenindorf, vkliuchennyi v obshchii sevooborotom s der. Ochka-Boiliar

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Vykopirovka s plana Seĭtlerskoĭ dachi razverstani︠ia︡ Kr.A.S.SD.R., na uchastok zemli otvedennyĭ KOMZET'u (Beǐs-Lekhem), pri provedenii rabot po zemreforme v 1930 g.

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Vykopirovka s plana Seĭtlerskoĭ dachi razverstani︠ia︡, Kr.A.S.SD.R., na uchastok zemli otvedennyĭ KOMZET'u (s -Kh. ART. "Rabotnik" - Aranda), pri provedenii rabot po zemreforme v 1930 g.

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