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71.
Ternary phases in the Al-rich region of the Al-Mn-Ni alloy system were studied at 950, 850 and 750 °C. Two new ternary intermetallic compounds were revealed: the φ-phase (Al5Co2-type, hP26, P63/mmc: a = 0.76632(16) and c = 0.78296(15) nm) and the κ-phase (κ-Al14.4Cr3.4Nil.1-type, hP227, P63/m: a = 1.7625(10) and c = 1.2516(10) nm). The formation of the O-phase (Pmmn; oP650; O-Al77Cr14Pd9-type; a = 2.3316(16), b = 1.2424(15) and c = 3.2648(14) nm) was confirmed and its chemical composition as well as thermodynamic stability was specified. 相似文献
72.
《Drug development and industrial pharmacy》2013,39(10):1547-1554
Context: Mixtures made of oil, water and surfactants give rise to a wide range of structure with different characteristics and phase manifestations.Objective: Aim of this paper is to build up and understand the phase diagram of a model ternary system (Water, Polysorbate 80 and isopropyl myristate) by the use of common techniques such as thermal analysis and rheology, in comparison with visual assessment and polarized light microscopy.Methods: Different ternary systems were prepared and analyzed by means of DSC and rheology in order to highlight the state of water (free, interphasal, bound water) and the samples structural characteristics.Results: The resultant phase diagram is divided into four different zones. Bound water zone is predominant at elevated surfactant/oil ratios, while as the surfactant/oil ratio decreases, DSC reveals the presence of free water. Interphasal water prevails at intermediate water and surfactant content which corresponds with gels systems. Mechanical spectra allow to discern between cubic (true gel) and lamellar mesophases (weak gel), while flow curves allow to distinguish among microemulsions, emulsions or lamellar mesophases.Discussion: A deeper characterization of a model ternary phase diagram is possible, with respect to the simple visual inspection, by the use of thermal analysis and rheology. The state of water molecules and the viscoelastic characteristics of the system allow to obtain important structural considerations.Conclusions: In conclusion, the knowledge of the state of water and of the viscoelastic characteristics of the systems allow a deeper understanding of the structural features of the ternary phase diagram. 相似文献
73.
V. S. Zenkov 《Powder Metallurgy and Metal Ceramics》2006,45(5-6):279-282
Kinetic features of adsorption-desorption processes for a nitrogen and oxygen mixture of gases, nitrogen and water vapor at
the surface of finely-dispersed amorphous powders of brown and black boron used to synthesize metal borides are studied. The
different adsorption-chemical activity of amorphous brown and black boron powders towards the main components of an air atmosphere
is determined. It is shown that the original boron, apart from hard impurity compounds, may carry at the surface gaseous constituents
with a capacity to change the physicochemical parameters of the system in the reaction zone, and to affect the phase composition
and quality of the product obtained.
__________
Translated from Poroshkovaya Metallurgiya, Nos. 5–6(449), pp. 79–84, May–June, 2006. 相似文献
74.
Jouyban-Gharamaleki A Clark BJ Acree WE 《Drug development and industrial pharmacy》2000,26(9):971-973
Applicability of the combined, nearly ideal, binary solvent/Redlich-Kister equation for calculating drug solubility in ternary mixtures is presented. The advantages of the proposed model are discussed and compared with a recently published equation that calculates the solute solubility in ternary solvent mixtures based on the mixture response methodology. 相似文献
75.
本文对铜(Ⅰ)-2,2′-联喹林与四溴、四碘、四氯四碘荧光素所形成的三元缔合配合物的萃取光度性质进行了较全面的研究。因离子对的等色性、缔合物的增敏效应以及向氯仿萃取液中加入乙醇或丙酮的增敏作用,大大提高了测定的灵敏度(ε>10~5)。本萃取光度体系又因保留了Cu(Ⅰ)专属试剂的螯合反应,从而具备良好的选择性。 相似文献
76.
Ternary sequences have been searched earlier with good merit factor or alternatively good discrimination as the search criterion.
When one of these measures is a search criterion, the other measure takes generally a poor value. As both of them are quantifications
of the abstract notion of a sequence with peaky autocorrelation, it is better to look for sequences with good values of merit
factor and discrimination simultaneously, without optimizing either measure. This is called Simonization. Simonized ternary
sequences are listed. 相似文献
77.
A ternary blend system of polystyrene (aPS), poly(α-methyl styrene) (PαMS), and poly(4-methyl styrene) (P4MS) (blends of three styrenic homopolymers of similar molecular structures) was investigated by using differential scanning calorimetry (DSC), polarized-light optical microscopy (POM), scanning electron microscopy (SEM), and solid-state 13C cross-polarization/magic angle spinning nuclear magnetic resonance (CP/MAS NMR). This ternary system of aPS/PαMS/P4MS exhibits a small miscibility loop only at relatively high percentages of PαMS (≥80%), while most of the aPS/PαMS/P4MS compositions exhibit two coexisting aPS/PαMS and aPS/P4MS phases in the immiscibility loop. In the immiscible loop, SEM measurements revealed evidence in contrasting with DSC for criteria of miscibility. DSC characterization revealed a single Tg for most ternary blend compositions; however, SEM graphs apparently indicated sub-micron phase domains, except for several PαMS-rich compositions (>80%). The and techniques using NMR were found to resolve the dilemma between the conventional thermal analysis and microscopy results, and indeed supported that the ternary blends at above 80% PαMS are completely homogeneous on the molecular level. Attempts have been made to resolve the seemingly contradictory interpretations on the complex ternary phase structures and domains from the DSC, and microscopy results. 相似文献
78.
三元复合硼化物基新型硬质合金 总被引:1,自引:0,他引:1
反应硼化烧结法制备的三元复合硼化物基新型硬质合金,具有优良的物理、化学、力学性能.本文就反应硼化烧结法的理念,新型硬质合金的种类、性能和应用做综述. 相似文献
79.
Microstructural characterization of Mg-Al-Sr alloys 总被引:1,自引:0,他引:1
The microstructural details of fourteen Mg-Al-Sr alloys were investigated in the as-cast form by a combination of scanning electron microscopy/energy dispersive spectrometer (SEM/EDS) analysis and quantitative electron probe microanalysis (EPMA). The heat transfer method coupled with the DSC measurement has been utilized to determine the solidification curves of the alloys. The morphology and the chemical composition of the phases were characterized. The microstructure of the alloys is primarily dominated by (Mg) and (Al4Sr). In the present investigation, ternary solid solubility of three binary compounds extended into the ternary system has been reported and denoted as: (Al4Sr), (Mg17Sr2) and (Mg38Sr9). The (Al4Sr) phase is a substitutional solid solution represented by MgxAl4−xSr and has a plate-like structure. The maximum solubility of Al in Mg17Sr2 was found to be 21.3 at%. It was also observed that Mg38Sr9 dissolved 12.5 at% Al. 相似文献
80.