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21.
Journal of Thermal Analysis and Calorimetry - In the present studies, the thermal behaviour of NaUO2BO3 has been investigated. This compound is a potential product of interaction between the...  相似文献   
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The title compound, cadmium bismuth dioxide chloride, CdBiO2Cl, was obtained as a white powder by reaction of solid BiOCl with CdO at 973 K. Ab initio crystal structure determination was carried out using X-ray powder diffraction techniques, including direct methods for atom location and Rietveld fitting for the final refinement. Being monoclinic, the crystal structure can be related to tetragonal Sillen layered phases. The main structural elements present are CdBiO2+ pleated metal–oxy­gen layers alternating with Cl layers along the c axis, whereas along the b axis, all atoms are on mirror planes. The formation of a strong Cd—Cl bond draws the layers together, causing layer deformation and a monoclinic distortion in the layer arrangement.  相似文献   
24.
Primary phosphines readily react with elemental sulfur and alkali metal hydroxides (MOH, M = Na, K, Cs) in the molar ratio 1:3:2 under mild conditions (70 °C, 0.5 h, ethanol) to afford alkali metal trithiophosphonates in good to high yields (72-90%).  相似文献   
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We review our study aimed at the creation of a unipolar laser with the efficient suppression of nonradiative relaxation between the laser subbands owing to strongly asymmetric-in-height barriers surrounding an active element. The asymmetry of the barriers causes the existence of a lower laser subband only within a narrow region of in-plane momenta. In such a way, one-phonon relaxation between the laser subbands can be significantly suppressed.  相似文献   
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The electron impact mass spectra of Be4O(CHal3CO2)6 (Hal = F, Cl) are reported. The compounds give two series of fragment ions, [Be4OLx]+ and [Be4OL+]+, where L is an intact ligand or its fragmentation product. The major ligand dissociation path is the elimination of CHal2CO2 with halogen transfer to the metal. Other processes of importance are the loss of acid anhydride fragments, CF2 with fluorine shift to the carboxyl group carbon atom, and halogens. Trinuclear ions also undergo decarboxylation, e.g. to give [Be2O(CHal3CO2)2(CHal3)]+. Both spectra contain comparatively intense peaks of double-charged ions. The fragmentation patterns are rationalized by stereochemical considerations.  相似文献   
27.
In the title hydrated adduct, 1,4,10,13‐tetraoxa‐7,16‐diazo­nia­cyclo­octa­decane bis(4‐amino­benzene­sulfonate) dihydrate, C12H28N2O42+·2C6H6NO3S·2H2O, formed between 7,16‐di­aza‐18‐crown‐6 and the dihydrate of 4‐amino­benzene­sulfonic acid, the macrocyclic cations lie across centres of inversion in the orthorhombic space group Pbca. The anions alone form zigzag chains, and the cations and anions together form sheets that are linked via water mol­ecules and anions to form a three‐dimensional grid.  相似文献   
28.
The crystal structure of [C10N2H10]2[P2Mo5O21(OH)2] · 2H2O, contains the heteropolyanion, [P2Mo5O21(OH)2]4—, together with diprotonated 4, 4′‐bipyridine. The heteropolyanion is built up from five MoO6 octahedra sharing four common edges and one common corner, capped by two PO3(OH) tetrahedra. The structure is stabilized by hydrogen bonds involving the hydrogen atoms of the 4, 4′‐bipyridine, water molecules and the oxygen atoms of the pentamolybdatobisphosphate. This is the first example that this kind of cluster could be isolated in the presence of a poly‐functional aromatic molecule ion. Crystal data: triclinic, P1¯ (No. 2), a = 9.983(2)Å, b = 11.269(2)Å, c = 17.604(4)Å, α = 73.50(3)°, β = 84.07(3)°, γ = 67.96(3)°; V = 1760.0(6)Å3; Z = 2; R1 = 0.037 and wR2 = 0.081, for 9138 reflections [I > 2σ(I)].  相似文献   
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The covalent functionalization of exfoliated hexagonal boron nitride (h-BN) nanosheets by nitrene addition is described. Integration of functionalized h-BN nanosheets within a polycarbonate matrix is demonstrated and was found to afford significant increases in mechanical properties. This integration methodology was further extended by the covalent modification of the h-BN nanosheets with polymer chains of a polycarbonate analogue, and the integration of the polymer modified h-BN within the polymer matrix.  相似文献   
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