Structures and constants of the products of nitration of 1-acetyl-1,2,3,4-tetrahydroquinolin-4-one

1,2, 3,4-Tetrahydroquinolin-4-one and its 1-acetyl derivative were nitrated, and it was established that mixtures of nitroquinolones are formed. 6-Nitro-1,2,3,4-tetrahydroquinolin-4-one, 6,8-dinitro-l,2,3,4-tetrahydroquinolin-4-one, 8-nitroquinolin-4-one, and 6,8-dinitroquinolin-4-one were isolated by means of preparative chromatography and characterized.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 671–673, May, 1982.     

Nanostructured Crystals of Fluorite Phases Sr1 – xRxF2 + x (R Are Rare-Earth Elements) and Their Ordering. 14: Concentration Dependence of the Defect Structure of Nonstoichiometric Phases Sr1 – xNdxF2 + x As Grown (x = 0.10, 0.25, 0.40, 0.50)

Crystallography Reports - The defect structure of as grown Sr1 – xNdxF2 + x (x = 0.10–0.50) crystals grown from a melt by...     

Nanostructured Crystals of Fluorite Phases Sr1 – xRxF2 + x (R Are Rare-Earth Elements) and Their Ordering. 13: Crystal Structure of SrF2 and Concentration Dependence of the Defect Structure of Nonstoichiometric Phase Sr1 – xLaxF2 + x As Grown (x = 0.11, 0.20, 0.32, 0.37, 0.47)

Crystallography Reports - The defect structure of as-grown SrF2 and nonstoichiometric phases Sr1 – xLaxF2 + x (x = 0.11, 0.20, 0.32, 0.37, 0.47) single...     

A study by the method of circular dichroism of the influence of various denaturing agents on cottonseed gossypulin (11S)

The structure of the reserve plant globulins is the main factor determining the functional properties of food proteins obtained from them. Under the action of various denaturing agents on cottonseed gossypulin, the main reserve protein, conformational changes take place which, in a number of cases affect both the secondary and the tertiary structures. Ten samples of gossypulin obtained under the action of acid, alkali, heat, and urea on the native molecule have been studied by the method of CD spectroscopy. The new protein products are systems relatively ordered with respect to their secondary structure but with a modified tertiary structure.Deceased.Institute of Chemistry of Plant Substances of the Uzbek SSR Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 234–241, March–April, 1990.     

Refinement of the twinned structure of cymrite from the Ruby Creek deposit (Alaska)

The mineral cymrite from the Ruby Creek deposit (Alaska) was reinvestigated by X-ray diffraction in a pseudo-orthorhombic unit cell with a = 5.3350(1) Å, b = 36.9258(8) Å, c = 7.6934(1) Å, β = 90.00(1)°. A twin law corresponding to a sixfold axis was revealed for the first time. The structure was refined in the monoclinic space group P12₁1 to the R factor of 5.4%. The Al and Si atoms are assumed to be ordered within a double layer. The rotation of the cation sublattice by 60° around the c axis leads to the disorder of the T sites in the crystal structure (T = Al, Si).     

Nadezhda Borisovna Bolotina (On the occasion of her 60th birthday)

Crystallography Reports -     

Shrinkage of epoxy cements during hardening

The authors give the results of measurements of the densities of two types of epoxy resin binders during setting from the initial liquid to the final state at room temperature. They assess the role of thermal shrinkage in the overall shrinkage deformation. They show that the coefficient of shrinkage relative to the state of lowest density is greater than the values given in the literature.Moscow Power Institute. Translated from Mekhanika Polimerov, No. 1, pp. 178–181, January–February, 1972.     

Isotropic lazurite: A cubic single crystal with an incommensurate three-dimensional modulation of the structure

The incommensurately modulated structure of the isotropic lazurite Na_6.41Ca_1.36K_0.04(Si_6.09Al_5.91)O₂₄(SO₄)_1.73Cl_0.17 from the Ba?kal region is solved in the (3 + 3)-dimensional symmetry group P23(γγ0) [where γ = 0.2154(1)] with the basic unit cell parameter a = 9.077(1) Å. The structure is refined to R ₀ = 0.04 for the main reflections and R ₁ = 0.15 for the satellite reflections. Six modulation waves are directed along the side diagonals of the unit cell. The structural model under investigation is compared with the twin model previously proposed for the same crystal. The structural data obtained are used to construct fragments of the modulated structure. Considering the constructed fragments of the modulated structure, it has become possible for the first time to reproduce and describe the three-dimensional modulation of the framework and to reveal its relation to modulations of intraframework atoms.