Browsing Chemistry Faculty Research, Publications and Presentations by Title
Now showing items 114-133 of 233
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Low thermal conductivity of the negative thermal expansion material, HfMo2O8
The thermal conductivity of the cubic polymorph of hafnium molybdate, HfMo2O8, was determined over the temperature range of 2-400 K. The values of thermal conductivity were low (0.64 +/- 0.15 W m(-1) K-1 at T=300 K for a ... -
Measuring the Geometric Component of the Transition-Probability in a 2-Level System
We describe the measurement of a component of the nonadiabatic transition probability in a two-level system that depends only on the path through parameter space followed by the Hamiltonian, and not on how fast the path ... -
Mechanical–Structural Investigation of Ion-Exchanged Lithium Silicate Glass using Micro-Raman Spectroscopy
Micro-Raman spectroscopy was used to determine the structural modifications occurring in a simple ion-exchanged glass. The base lithium silicate composition 30Li2O–70SiO2 was studied as it underwent ion exchange, Li+ ↔ K+, ... -
Microwave-accelerated synthesis of benzyl 3,5-dimethyl-pyrrole-2-carboxylate
Benzyl 3,5-dimethyl-pyrrole-2-carboxylate, a very useful pyrrole in porphyrin and dipyrromethene synthesis, can be synthesized via the Knorr-type reaction, but in low yield. Alternative routes to benzyl 3,5-dimethyl-pyrr ... -
Microwave-assisted reduction of F-BODIPYs and dipyrrins to generate dipyrromethanes
The reduction of BODIPYs and dipyrrins to dipyrromethanes, via a reaction involving ethylene glycol and sodium methoxide, is reported. When benzyl alcohol is used in place of ethylene glycol, the addition of 2,4-dinitrop ... -
Mixed Transition Metal Titanate and Vanadate Negative Electrode Materials for Na-Ion Batteries (Preprint)
Sodium-ion batteries have the potential to be a low cost, sustainable replacement for lithium-ion batteries in large scale energy storage. The lack of practical negative electrode materials limit the development of Na-ion ... -
Mössbauer and Electrochemical Investigations of Carbon-Rich Fe1-xCx Films (Preprint)
A thin film binary library of carbon-rich Fe1-xCx (0.47 ≤ x ≤ 0.97) alloys was prepared by combinatorial sputtering of carbon and iron. The sputtered library was characterized by X-ray diffraction and room temperature 57Fe ... -
Nanoindentation Study of the Surface of Ion-Exchanged Lithium Silicate Glass
Variations in mechanical properties (stiffness and hardness) were measured as a function of case depth in ion-exchange glasses using nanoindentation. A simple silicate composition, 30Li2O–70Si2O, was exchanged (Li+ ↔ K+) ... -
The nature of ammonium ion disorder in ammonium tetrafluoroaluminate, NH4AlF4.
To clarify previous conflicting reports concerning the existence of an order-disorder phase transition in NH4AlF4 at T ?150 K, the heat capacity of this compd. was measured from T = 15 to 305 K, by adiabatic calorimetry. ... -
NixSi1-x Alloys Prepared by Mechanical Milling as Negative Electrode Materials for Lithium Ion Batteries
NixSi1-x (0 ≤ x ≤ 0.5, x = 0.05) alloys were prepared by ball milling and studied as anode materials for lithium ion batteries. Nanocrystalline Si/NiSi2 phases were formed for x ≤ 0.25. The NiSi phase was observed for ... -
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Phase transitions in M(ClO4)2.6H2O (M = magnesium, zinc). Investigations by adiabatic calorimetry and infrared spectroscopy.
IR spectra of Mg(ClO4)2.6H2O at 10 K indicate a complex structure contg. at least 16 distinct types of H2O protons. At 107.9 K this structure transforms sharply to a much simpler disordered form (?Strans = 7.754 J K-1 ... -
Phase transitions in metal perchlorate hydrates: the supposed hydrate-to-pseudohydrate transformations.
A polemic. The hydrate-to-pseudohydrate transformations in metal perchlorate hydrates reported by M. B. Patel and H. D. Brist (ibid. 1983, 79, 4489) and Solid State Commun. (48, 139 (1983)) as well as the suggested ...