nonstoichiometric


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nonstoichiometric

(ˌnɒnˌstɔɪkɪəˈmɛtrɪk)
adj
(Chemistry) chem (of a solid compound) having a composition in which the ratio of the atoms present is not a simple integer
References in periodicals archive ?
"Enamel resembles a layer of natural inorganic crystalline mineral and is primarily composed of nonstoichiometric fluoridated carbonate apatite crystals that are tightly packed with well-defined orientations to ensure striking hardness," said Dr.
Usually, the necessary oxygen vacancy concentration in the metal oxide films for the memristor devices is achieved either by deposition of the nonstoichiometric oxide films or by the postdeposition vacuum annealing.
Nevertheless, as the activity of these species is poorer under heating process within humidity, the Cu oxide films were nonstoichiometric.
The EDS analysis indicates sulfur-rich sulfides (nonstoichiometric FeS) in the crystalline region depicted in Figure 6(f).
Ti[O.sub.2] usually presents oxygen vacancies; these defects can be controlled experimentally based on nonstoichiometric conditions of synthesis (Ti excess or oxygen deficiency) or by heating the sample in a vacuum at 900 K [37-39].
Ciucci, "Nonstoichiometric oxides as low-cost and highly-efficient oxygen reduction/evolution catalysts for low-temperature electrochemical devices," Chemical Reviews, vol.
Kiridena, "Ti[O.sub.2] and W[O.sub.3] semiconductor particles in contact: photochemical reduction of W[O.sub.3] to the nonstoichiometric blue form," Semiconductor Science and Technology, vol.
For nonstoichiometric formulations with excess of epoxy monomer, the epoxy rings could, in principle, react with these hydroxyl groups, but this secondary reaction will not contribute to the reduction of the number of hydrophilic OH groups [24, 25].
A number of reports have been published for the synthesis of g-[C.sub.3][N.sub.4] and even other graphitic forms with nonstoichiometric compositions on the basis of various techniques such as CVD [8-10], solid reaction [11-17], solvothermal method [18-22], and thermal decomposition of compounds [23-26].
This relatively high value can be associated with the severe plastic deformations, which introduces different types of defects such as dislocations, grain boundaries, gaps, and stacking faults and it can be also explained by the formation of a nonstoichiometric composition of the austenite phase.
Sakka, "Calibration-free analysis of immersed brass alloys using long-ns-duration pulse laser-induced breakdown spectroscopy with and without correction for nonstoichiometric ablation," Spectrochimica Acta Part B: Atomic Spectroscopy, vol.
Consequently, the nitride phases are nonstoichiometric compounds, and nanograins contain a large number of additional sites at the locations of nitrogen atoms.