ECSim2.0 package and simulation of X-ray emulsion chamber experiments

The ECSim 2.0 package is being developed on the basis of the ECSim software package to simulate the development of nuclear-electromagnetic cascades initiated by different particles in a layered medium. Some characteristics of ECSim 2.0 and the results obtained using this package in simulation of the passage of electrons and γ rays through the gamma block of X-ray emulsion chambers in the Pamir Collaboration experiment are discussed. The results obtained are compared with the data of other researchers.     

A novel chelatofore functionalized spiropyran of the 2‐oxaindane series

A novel chelatofore functionalized spiropyran of the 2‐oxaindane series, namely 8‐formyl‐7‐hydroxy‐3′,3′‐dimethylspiro[2H‐chromene‐2,1′(3′H)‐2‐benzofuran], C₁₉H₁₆O₄, is reported. In the crystalline state, dimers are formed as a result of the π–π stacking of aromatic groups of the 2H‐chromene part of the molecule and C—H...O interactions. The C_spiro—O bond length in the pyran ring is 1.4558 (10) Å, which is longer than or equal to the bond length in thermo‐ and photochromic 2‐oxaindane spiropyrans synthesized previously, except for the 7,8‐benzo/6‐NO₂ derivative, in which this bond length is 1.465 (2) Å.     

Transition metal complexes based on 2,4-dihydroxyisophthalic anhydride and its functionalized derivative

Oligomeric complex compounds of Cu(II), Ni(II), Mn(II), Zn(II), and Cd(II) with 2,4-dihydroxyisophthalic aldehyde and its bis-hydrazone on the basis of 4-pyridinecarboxylic acid hydrazide are prepared. Probable structures of the complexes are proposed, based on the results of physico-chemical investigations by the methods of IR and ¹H NMR spectroscopy, magnetochemistry and molecular weight determining by Rast’s method.     

Crystal structure of the polycyclic oxidation product of 1′-phthalazinylhydrazone of 2-formylpyrrole

Phthalazinylhydrazone of 2-formylpyrrole is synthesized, the values of ionization constants are determined, and quantum chemical calculation of the geometry and total energy of possible tautomers is performed. The structure of the cyclic oxidation product of hydrazone 3-(1H-pyrrolyl-2)-[1,2,4]-triazolo(3,4-a)phthalazine existing in the crystal in the form of dimers linked by two hydrogen bonds is described.     

Reversible sorption of hydrogen on the novel hybrid material based on mesoporous chromium(<Emphasis Type="SmallCaps">iii</Emphasis>) terephthalate with included rhenium clusters

The interaction of mesoporous chromium(iii) terephthalate [Cr₃O(C₈H₄O₄)₃F(H₂O)₂] (MIL-101) with an aqueous solution of the anionic cluster [Re₄S₄F₁₂]⁴⁻ ({Re₄}) afforded a novel hybrid material {Re₄}@MIL-101. According to the elemental analysis data, one cavity of the nanoporous framework contains up to two-three tetranuclear rhenium clusters. The hybrid sorbent obtained reversibly absorbs up to 3.7 wt.% hydrogen at 77 K and 30 atm.     

Determination of the number of active sites in the metathesis reactions of 1-hexene and cyclopentene on the WC16 -Sn(CH3)4 catalytic system by an isotope method

Conclusion The percentages of primary carbene sites in the metathesis of 1-hexene and polymerization of cyclopentene on the WCl₆-Sn(CH₃)₄ catalytic system, as indicated by a radioisotope method, are 1.3 and 1.4%, respectively, relative to starting WCl₆. The Sn(CH₃)₄ methyl groups which participate in the formation of the starting active complexes enter the reaction products.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 12, pp. 2805–2807, December, 1986.     

Elastic moduli of vortex lattices within nonlocal London model

Vortex lattice (VL) elastic response is analyzed within the nonlocal London model which holds for high-kappa clean superconductors. The squash modulus vanishes at the field H( square) where VL undergoes a square-to-rhombus transition. For H>H( square), where the square VL is stable, the rotation modulus turns zero at H = H(r), indicating VL instability to rotations. The shear modulus depends on the shear direction; the dependence is strong in the vicinity of H( square) where the square VL is soft with respect to the shear along [110]. The H dependences of the moduli are evaluated for LuNi(2)B(2)C.     

Wave scattering through classically chaotic cavities in the presence of absorption: An information-theoretic model

We propose an information-theoretic model for the transport of waves through a chaotic cavity in the presence of absorption. The entropy of the S-matrix statistical distribution is maximized, with the constraint