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A systematic X-ray powder diffraction study of the Gd 2 O 3 -BaCO 3 -CuO system over the temperature range 920-980°C in ambient air is presented as a function of cation composition. In the pseudobinary regions the phases BaGd 2 O 4 , “Gd 2 Ba 4 O 7 ,” Gd 2 CuO 4 , and BaCuO 2 were observed. Mass balance data suggest that “Gd 2 Ba 4 O 7 ” is actually Gd 2 Ba 4 O 7 · CO 2 . In the pseudoternary region the phases Gd 2 BaCuO 5 , GdBa 3 Cu 2 O y , and GdBa 2 Cu 3 O 6.5+ x were identified. Although GdBa 2 Cu 3 O 6.5+ x exhibited minimal solid solution, GdBa 3 Cu 2 O y evidenced a significant solubility range. Lattice parameters are presented and from a phase analysis subsolidus relationships are constructed. The system is compared with related systems.

A systematic X-ray powder diffraction study of the Sm 2 O 3 BaCO 3 CuO system over the temperature range ∼920–980°C is presented as a function of cationic molar ratios. In the pseudobinary regions the phases BaSm 2 O 4 , Sm 2 CuO 4 , and BaCuO 2 were observed; in the pseudoternary region Sm 2 BaCuO 5 , SmBa 3 Cu 2 O z , Sm 3 Ba 3 Cu 6 O y , and SmBa 2 Cu 3 O y were identified. A solid solution region was found in the vicinity of SmBa 2 Cu 3 O y . Lattice parameters are presented for each compound detected. A pseudoternary phase diagram is presented: subsolidus relationships are indicated. This system is compared with related lanthanoid-barium-copper oxide systems; only the europium system exhibits comparable phases.

Systematic X-ray powder diffraction studies of the Nd{sub 2}O{sub 3}-BaCO{sub 3}-CuO and PrO{sub x}-BaCO{sub 3}-CuO systems at {approximately} 950{degree}C in air are presented as a function of cation molar ratios. In the pseudo-binary regions BaCuO{sub 2} was observed in both systems; Pr{sub 2}CuO{sub 4} and BaPrO{sub 3}, and Nd{sub 2}CuO{sub 4} and BaNd{sub 2}O{sub 4}, were observed in the Pr and Nd systems, respectively. BaPr{sub 2}O{sub 4} could be prepared only in a reducing atmosphere. In the pseudo-ternary regions the 123 and 336 phases were observed in the Pr system; the 123, 336, and 311 phases were observed in the Nd system. In the Pr system extensive solid-solution prevails between the 110, 123, and 336 phases and between the latter two phases and CuO. In the Nd system solid-solution was observed between 311, and 123, and 336 phases, and between the latter two phases and CuO.

The dehydration process of the fibrillar potassium, rubidium and cesium isopolytrimolybdates was investigated by thermogravimetry and X-ray diffractometry. The dehydration took place in one step and the trimolybdates of general formula X2Mo3O10 (whereX=K, Rb or Cs) were obtained.

The thermal transformations in solid nickel (II) hexaamminonitrate have been studied by the X-ray powder diffraction method. X-ray patterns between room temperature and 80 K are interpreted. It has been found that the compound exists in three modifications: I-cubic F, II-cubic P and III-orthorhombic. The mechanism of the transformations I→II and II→III is discussed. The phase transitions are reversible, showing hysteresis.

[(n—Bu)4N]3 W(CN)8 is investigated by X-ray powder and wide-line proton magnetic resonance methods. The temperature dependences of the lattice parameters and 1H second moment of the resonance lines are recorded in the range of 77 to 383 K. On ground of the dynamical model proposed for the crystal lattice of the compound an analysis of the experimental data is made. The reorientations of different groups of the cations are proved to be responsible for the observed effects.

Il existe deux transformations a basses temperatures, bien que la modification des cristaux du titre soit stable entre 77 et 383 K. Tous les cations sont equivalents d'un point de vue dynamique et occupent les sites de meme symetrie locale. La transition de phase du premier ordre n'est pas observee. Les transitions dans ces composes sont reliees aux differents etats dynamiques des cations qu'a un changement de stereochimie

Studies of the i.r. spectra, lattice parameters and the proton second moment in [n-Bu4N]3[Mo(CN)8] over the 77K to 383 K region are reported.1Hn.m.r. data provide evidence for different rotational processes which are discussed in some detail. Atca. 260 K and 295 K the compound exibits anomalous changes in i.r. spectra and lattice parameters. The results reveal the existence of polymorphism in solid tetrabutylammonium octacyanomolybdate(V).

A general purpose centrifuge method for measuring particle-size distribution of air-filter inlet, outlet and catch dust samples is demonstrated. Treatment and analysis of data to determine air-cleaner performance based on size distribution is shown for two types of air filters, a louver and a glass-fiber media filter. The advantages and limitations of the method and interpretations of results associated with the application of these procedures for arriving at efficiency versus particle-size performance curves, and for predicting filter efficiency for any given dust are discussed.Copyright © 1965 by ASME

Coronary flow per minute per 100 Gm. of heart with venous drainage into the coronary sinus as measured by the nitrous oxide procedure was compared in the dog with left coronary artery inflow per 100 Gm. of heart perfused by this artery as measured by the rotameter. The error arising from epicardial leak of nitrous oxide was prevented or quantitated by appropriate coverage of the heart. Extremes of the comparisons were +21 and -22 per cent, with an average variation of ±12.4 per cent. The nitrous oxide method is regarded as giving semiquantitative coronary flow values per 100 Gm. of left heart in the dog.

Tetra- n -butylammonium octacyanotungstate(V) has been found to exist in three phases at the temperature range 90–353 K. The IR and 1 H-NMR spectra as well as thermogravimetric and powder diffraction studies support these structural changes. The phase transitions were found in the temperature range 273–283 K (T 1 ) and 333–343 K (T 2 ).