High resolution rotational spectra of ¹⁰BH₃CO, ¹¹BH₃CO, ¹¹BD₃CO, PH₂D and CD₃CN were studied to obtain information concerning the electronic and magnetic properties of these molecules. From the analysis of the hyperfine structure of the rotational spectra of the molecules the following constants were determined: rotational constants (B₀), nuclear quadrupole coupling constants (eOq [x], spin-spin constants D (X-Y) and spin rotation constants (C[x]). The two instruments used in these experiments were a Stark modulated microwave spectrometer and a molecular beam maser spectrometer. The J = 0 to 1, F₁ = 3 to 3 and F₁ = 3 to 4 transitions of ¹⁰BH₃CO were studied. The molecular constants in KHz which were derived from the spectral analysis were: B(,0) = 8980060.3 (+/-) 1.0, eQqₐₐ (¹⁰B) = 3463.- (+/-) 8.0, C(¹⁰B) = .2 (+/-) .2, D(¹⁰B-H) = -2.8 (+/-) .2, D(H-H) = -7.2 (+/-) .5 and C(H) = 0.0 (+/-) .7. All three of the F₁ components of the J = 0 to 1 rotational transition of ¹¹BH₃CO were observed. The molecular constants in KHz which were obtained from the data analysis were: B₀ = 8657333.8 (+/-) .6, eQqₐₐ (¹¹B) = 1661.9 (+/-) 2.3, C(¹¹B) = .7 (+/-) .3, D(¹¹B-H) = 8.3 (+/-) .4, D(H-H) = -6.8 (+/-) .2 and C(H) = .4 (+/-) .4. Only spectra of the J = 0 to 1, F₁ = 3/2 to 3/2 transition of ¹¹BD₃CO were obtained. From the analysis of the spectra the following molecular constants were derived: eQqₐₐ (D) = -48.5 (+/-) 2.3, eQq(,zz)(D) = 116.9 (+/-) 5.4, C(D) = 0.0 (+/-) .8 and D(¹¹B-H) = -1.2 (+OR-) .3. The investigation of the 4₀₄ to 4₁₄ and 1₁₁ to 1₀₁ rotational transitions of PH₂D was unsuccessful in determining any molecular parameters. The spectra of the 4₀₄ to 4₁₄ rotational transition were not amenable to analysis and no spectra were obtained for the 1₁₁ to 1₀₁ rotational transitions. The three components of the J = 0 to 1 rotational transitions of CD₃CN were studied with the maser in the two cavity configuration. The constants in KHz which were determined were: B₀ = 7857978.7 (+/-) .1, eQqₐₐ(N) = -4229.2 (+/-) .6, eQqₐₐ(D) = -55.1 (+/-) .4, eQq(,zz)(D) = 165.5 (+/-) 5.0, C(,N) = 1.7 (+/-) .1 and C(,D) = 0.0 (+/-) .03.

No description available.

Tsang Hing Wa = 梯度粒子系統的扭轉運動 / 曾慶華. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references (leaves 66-68). / Text in English; abstracts in English and Chinese. / Tsang Hing Wa = Ti du li zi xi tong de niu zhuan yun dong / Zeng Qinghua. / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Localization --- p.1 / Chapter 1.1.1 --- Localization by Potential Confinement --- p.1 / Chapter 1.1.2 --- Localization by Interference --- p.2 / Chapter 1.2 --- Graded Materials --- p.2 / Chapter 1.3 --- Rotational Motion --- p.3 / Chapter 2 --- Torsional Motion of Rotating Particles with Graded Couplings / Chapter 2.1 --- Linear Couplings --- p.5 / Chapter 2.1.1 --- Model and Formalism --- p.5 / Chapter 2.1.2 --- Gradient in Coupling Constant --- p.7 / Chapter 2.1.3 --- Gradient in Moment of Inertia --- p.8 / Chapter 2.1.4 --- Numerical Results --- p.9 / Chapter 2.1.5 --- Discussion and Conclusion --- p.14 / Chapter 2.2 --- Non-Linear Couplings --- p.14 / Chapter 2.2.1 --- Model and Formalism --- p.14 / Chapter 2.2.2 --- Gradient in Coupling Constant --- p.16 / Chapter 2.2.3 --- Gradient in Moment of Inertia --- p.16 / Chapter 2.2.4 --- Numerical Results --- p.17 / Chapter 2.2.5 --- Discussion and Conclusion --- p.29 / Chapter 3 --- Torsional Motion of Rotating Particles with graded potential --- p.30 / Chapter 3.1 --- Linear Interaction --- p.30 / Chapter 3.1.1 --- Model and Formalism --- p.30 / Chapter 3.1.2 --- Gradient in On-site Torsional Potential --- p.32 / Chapter 3.1.3 --- Numerical Results --- p.33 / Chapter 3.1.4 --- Discussion and Conclusion --- p.43 / Chapter 3.2 --- Non-linear Interaction --- p.43 / Chapter 3.2.1 --- Model and Formalism --- p.43 / Chapter 3.2.2 --- Numerical Results --- p.45 / Chapter 3.2.3 --- Chaotic Effect --- p.62 / Chapter 3.2.4 --- Discussion and Conclusion --- p.64 / Chapter 4 --- Conclusion --- p.65 / Bibliography --- p.66

Au Yuen-yee. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references (leaves 140-152). / Abstracts in English and Chinese. / Abstract --- p.iii / Acknowledgements --- p.v / Chapter Chapter One: --- General Background and Introduction --- p.1 / Chapter 1 -1 --- Introduction --- p.1 / Chapter 1-2 --- Three-Bond Coupling Constants (3J) --- p.1 / Chapter 1-2-1 --- Development of the Karplus Equation --- p.1 / Chapter 1-2-2 --- Application of3J in the Conformational Analysis of Nucleic Acid --- p.4 / Chapter 1-2-3 --- Problem of Accuracy for3 J Measurement --- p.7 / Chapter 1-3 --- Two-Bond Coupling Constants (2J) --- p.7 / Chapter 1-3-1 --- The Use of the Projection Method --- p.7 / Chapter 1-3-2 --- 2J Coupling Constant Involving Hydrogen Bonds --- p.8 / Chapter 1-4 --- One-Bond Coupling Constants (1J) --- p.10 / Chapter 1-5 --- Conclusion --- p.11 / Chapter Chapter Two: --- Experimental Section / Chapter 2-1 --- Introduction --- p.12 / Chapter 2-2 --- Heteronuclear Multiple-Quantum Coherence (HMQC) Experiment --- p.12 / Chapter 2-3 --- Experimental Section --- p.15 / Chapter 2-3-1 --- Sample Preparation --- p.15 / Chapter 2-3-2 --- NMR Spectroscopy --- p.16 / Chapter Chapter Three: --- Theory of Nuclear Spin-Spin Coupling Constants --- p.18 / Chapter 3-1 --- Introduction --- p.18 / Chapter 3-2 --- Application of Finite Perturbation Theory on Nuclear Spin-Spin Coupling --- p.18 / Chapter 3-3 --- Methodology --- p.22 / Chapter Chapter Four: --- DFT and NMR Study of1JCH Coupling Constants --- p.28 / Chapter 4-1 --- Introduction --- p.28 / Chapter 4-2 --- Nomenclature and Definition of Structural Parametersin DNA and RNA --- p.28 / Chapter 4-2-1 --- "Nomenclature, Symbols and Atomic Numbering Schemes" --- p.28 / Chapter 4-2-2 --- Definition of Torsion Angles and their Rangesin Nucleotides --- p.31 / Chapter 4-2-3 --- Description of the Furanose Ring --- p.31 / Chapter 4-3 --- Results and Discussion --- p.37 / Chapter 4-3-1 --- Basis Set Effect --- p.37 / Chapter 4-3-2 --- Relative Conformational Energy Profiles --- p.37 / Chapter 4-3-3 --- Comparison of the Dependence of 1JCH Coupling Constants on Conformational Changes With and Without the DNA Backbone --- p.40 / Chapter 4-3-4 --- Effect of Backbone 3'- and 5'-Phosphate --- p.42 / Chapter 4-3-5 --- Effect of Glycosidic Torsion Anglex --- p.49 / Chapter 4-3-6 --- Effect of Ring Conformation with Fixed Glycosidic Torsion Anglex --- p.52 / Chapter 4-3-7 --- Effect of Torsion Angle α --- p.52 / Chapter 4-3-8 --- Effect of Torsion Angle β --- p.53 / Chapter 4-3-9 --- Effect of Torsion Angle γ --- p.56 / Chapter 4-3-10 --- Effect of Torsion Angle ε --- p.59 / Chapter 4-3-11 --- Effect of Torsion Angle ζ --- p.61 / Chapter 4-3-12 --- Effect of Base Pairing --- p.65 / Chapter 4-3-13 --- Effect of Base Stacking from the (n-1) and (n+1) Base --- p.65 / Chapter 4-3-14 --- Comparison of Experimental and Theoretical Data --- p.68 / Chapter 4-4 --- Conclusion --- p.74 / Chapter Chapter Five: --- DFT Study of 2JCH and 3JCH Coupling Constants --- p.79 / Chapter 5-1 --- Introduction --- p.79 / Chapter 5-2 --- Results and Discussion on 2JCH Coupling Constants --- p.79 / Chapter 5-2-1 --- Effect of Backbone 3'- and 5'-Phosphate --- p.79 / Chapter 5-2-2 --- Effect of Ring Conformation with Fixed Glycosidic Torsion Anglex --- p.82 / Chapter 5-2-3 --- Effect of Glycosidic Torsion Anglex --- p.87 / Chapter 5-2-4 --- Effect of Torsion Angleγ --- p.87 / Chapter 5-2-5 --- Effect of Torsion Angle ε --- p.90 / Chapter 5-2-6 --- Effect of Base Pairing --- p.90 / Chapter 5-2-7 --- Effect of Base Stacking from the (n-1) and (n+1) Base --- p.90 / Chapter 5-3 --- Results and Discussion on 3JCH Coupling Constants --- p.95 / Chapter 5-3-1 --- Effect of Backbone 3'- and 5'-Phosphate --- p.95 / Chapter 5-3-2 --- Effect of Ring Conformation with Fixed Glycosidic Torsion Anglex --- p.95 / Chapter 5-3-3 --- "Effect of Different Torsion Angles (X,α,β,γ,ε,and ζ)" --- p.100 / Chapter 5-3-4 --- Effect of Base Pairing --- p.100 / Chapter 5-3-5 --- Effect of Base Stacking from the (n-1) and (n+1) Base --- p.105 / Chapter 5-4 --- Conclusion --- p.105 / Chapter Chapter Six: --- Conclusion --- p.111 / Appendix A Product Operator Formalism on HMQC Pulse Scheme --- p.113 / Appendix B Finite Perturbation Theory --- p.115 / Appendix C Supplementary Figures of Chapter Four --- p.118 / Appendix D Some of the NMR Spectra --- p.134 / References --- p.140

Thesis (M. Sc. (Chemistry)) --University of Limpopo, 2018 / The dissertation describes the use of 2-benzenesulfonyloxyquinoxaline as a good coupling partner for different amine substrates. The palladium-mediated cross- coupling of aryl electrophiles and amines has become a widely used method of constructing arylamine frameworks. The formation of carbon-nitrogen bonds was accomplished via palladium-catalysed Buchwald-Hartwig amination employing different amine substrates to yield substituted quinoxaline-2-amines compounds in good to moderate yields. Buchwald ligands (Xphos, tButylxphos and BrettPhos), were varied with different amine substrates in an attempt of improving the yields. Compounds 81a N-phenylquinoxalin-2-amine and 82b, N-benzylquinoxalin-2-amine were obtained with the yield over 70 % employing Xphos as the ligand. Significant attention has also been given to the application of cross coupling reaction protocols in substrates bearing electron withdrawing substituents. The presence of deactivating groups on the arylamine such as fluoro, nitro and iodo proved to be a challenge as only few compounds were synthesised in moderate yields. Compound 81b, N-(4-fluorophenyl)quinoxalin-2-amine which has electronegative atom attached, showed significant improvement when employing tButyl-Xphos ligand rather than XPhos since the yield improved from 10 % to 71 %. Furthermore, nucleophilic substitution on Buchwald-Hartwig coupled compounds by treating them with alkyl iodides was successful when using methyl and ethyl electrophiles on the N-H group of 81a 2-quinoxalineamine. The synthesised quinoxaline derivatives comprised 7 novel compounds. The in vitro analysis on anti-tubercular screening against H37RvMA strains of Mycobacterium tuberculosis was conducted on 9 compounds. The results revealed none of the compounds to have promising inhibition percentages against Mycobacterium tuberculosis when compared with rifampicin which was used as a positive control. Screening against malaria with chloroquine as the control also did not yield any active compounds.

The goal of this project was to study the deliquescence kinetics of aerosol particles of atmospheric significance. In the course of this work a novel experimental method was developed, which utilizes the measurement of the water vapor loss in laminar aerosol flow to determine vapor uptake on the aerosol surface. The newly designed flow tube apparatus uses a system of Nafion based dryers and humidifiers, which greatly simplifies the optimization and control of the relative humidity in the aerosol flow. The design, which also utilizes a movable inlet, enables easy variation of the aerosol residence time in the deliquescence reactor, while keeping other experimental conditions constant. In this study, a numerical retrieval procedure was used to characterize aerosols in situ from their IR extinction spectra. The procedure allows that the aerosol size, number distribution, phase and composition be determined, provided the optical constants of all the components (materials) comprising the aerosol are known. For the purpose of studying the deliquescence kinetics of ammonium sulfate aerosol and monitoring their evolution from solid to liquid (state), we have acquired a set of optical constants for a range of (NH4)2SO4 compositions. A set of experiments in a somewhat modified flow tube set up was performed to produce AMS aerosols of known composition, including solid, saturated (water) solution (40 % wt.) and a series of diluted solutions with composition ranging between 40 and 10 % wt. in 5 % increments. The IR spectra of these model aerosols were used to derive the optical constants, using an inversion method proposed by Clapp. The derived refractive indices, which cover the spectral range from 590 to 5990 cm-1 with 2 cm-1 resolution, were compared with those already available in the literature. Using various examples to compare the quality of fittings to experimental spectra, we demonstrated that our optical constants present an improvement relative to those previously reported by B. Toon’s (for crystalline AMS) and S. Martin’s (for AMS solution). The suitability of applying this procedure to ammonium sulfate aerosols and its sensitivity to spectral range was also investigated and discussed. As a preparatory step for the deliquescence kinetics study, our new flow tube apparatus and the tools for the characterization of aerosol were verified in a standard deliquescence experiment performed on (NH4)2SO4 aerosols. The deliquescence process of an equilibrated aerosol flow was monitored as a function of increasing humidity and the deliquescence relative humidity (DRH) determined to be 79.6 ± 0.85 % which is, within experimental uncertainty, in an excellent agreement with the results reported by other research groups. In the kinetic experiment, a flow of solid (NH4)2SO4 aerosols is pre-humidified to a humidity close to, but enough below DRH that there is no detectable amount of liquid aerosols in the system. Such an equilibrated aerosol flow was introduced to the deliquescence reactor where it is further humidified in a controllable manner, by varying the position of the movable inlet. The amount of water transferred to the aerosol through the Nafion membrane was closely monitored, as well as the resulting increase in the water content in the aerosol flow (both gaseous and liquid). This was achieved by measuring the RHs and flow rates of the aerosol and humidification flow, and the characterization of aerosol composition and concentration using their IR spectra. The experimental conditions and aerosol residence times in the reactor where chosen such that no other diluted solution except for saturated (NH4)2SO4 droplets were produced in the process. The number distribution of deliquesced aerosols and the corresponding change in the water content in the aerosol flow were used by a newly developed kinetic model to determine the kinetics of the deliquescence process. Assuming fully developed laminar flow conditions, the water vapor concentration in the flow and its depletion in the presence of aerosol was modeled, to retrieve the value of the water vapor uptake. In the case of micron-sized ammonium sulfate aerosols, which were used in this study, the uptake coefficient,, was determined to be 0.0072 ± 6.54x10-3. The uncertainty associated with this value, as well as the suggested improvements to the experimental procedure and the kinetic model in order to reduce the uncertainty were discussed.

The goal of this project was to study the deliquescence kinetics of aerosol particles of atmospheric significance. In the course of this work a novel experimental method was developed, which utilizes the measurement of the water vapor loss in laminar aerosol flow to determine vapor uptake on the aerosol surface. The newly designed flow tube apparatus uses a system of Nafion based dryers and humidifiers, which greatly simplifies the optimization and control of the relative humidity in the aerosol flow. The design, which also utilizes a movable inlet, enables easy variation of the aerosol residence time in the deliquescence reactor, while keeping other experimental conditions constant. In this study, a numerical retrieval procedure was used to characterize aerosols in situ from their IR extinction spectra. The procedure allows that the aerosol size, number distribution, phase and composition be determined, provided the optical constants of all the components (materials) comprising the aerosol are known. For the purpose of studying the deliquescence kinetics of ammonium sulfate aerosol and monitoring their evolution from solid to liquid (state), we have acquired a set of optical constants for a range of (NH4)2SO4 compositions. A set of experiments in a somewhat modified flow tube set up was performed to produce AMS aerosols of known composition, including solid, saturated (water) solution (40 % wt.) and a series of diluted solutions with composition ranging between 40 and 10 % wt. in 5 % increments. The IR spectra of these model aerosols were used to derive the optical constants, using an inversion method proposed by Clapp. The derived refractive indices, which cover the spectral range from 590 to 5990 cm-1 with 2 cm-1 resolution, were compared with those already available in the literature. Using various examples to compare the quality of fittings to experimental spectra, we demonstrated that our optical constants present an improvement relative to those previously reported by B. Toon’s (for crystalline AMS) and S. Martin’s (for AMS solution). The suitability of applying this procedure to ammonium sulfate aerosols and its sensitivity to spectral range was also investigated and discussed. As a preparatory step for the deliquescence kinetics study, our new flow tube apparatus and the tools for the characterization of aerosol were verified in a standard deliquescence experiment performed on (NH4)2SO4 aerosols. The deliquescence process of an equilibrated aerosol flow was monitored as a function of increasing humidity and the deliquescence relative humidity (DRH) determined to be 79.6 ± 0.85 % which is, within experimental uncertainty, in an excellent agreement with the results reported by other research groups. In the kinetic experiment, a flow of solid (NH4)2SO4 aerosols is pre-humidified to a humidity close to, but enough below DRH that there is no detectable amount of liquid aerosols in the system. Such an equilibrated aerosol flow was introduced to the deliquescence reactor where it is further humidified in a controllable manner, by varying the position of the movable inlet. The amount of water transferred to the aerosol through the Nafion membrane was closely monitored, as well as the resulting increase in the water content in the aerosol flow (both gaseous and liquid). This was achieved by measuring the RHs and flow rates of the aerosol and humidification flow, and the characterization of aerosol composition and concentration using their IR spectra. The experimental conditions and aerosol residence times in the reactor where chosen such that no other diluted solution except for saturated (NH4)2SO4 droplets were produced in the process. The number distribution of deliquesced aerosols and the corresponding change in the water content in the aerosol flow were used by a newly developed kinetic model to determine the kinetics of the deliquescence process. Assuming fully developed laminar flow conditions, the water vapor concentration in the flow and its depletion in the presence of aerosol was modeled, to retrieve the value of the water vapor uptake. In the case of micron-sized ammonium sulfate aerosols, which were used in this study, the uptake coefficient,, was determined to be 0.0072 ± 6.54x10-3. The uncertainty associated with this value, as well as the suggested improvements to the experimental procedure and the kinetic model in order to reduce the uncertainty were discussed.

ABSTRACT Hydrophobic organic pollutants (HOPs) are in general characterized by high toxicity, long environmental half-life and high bio-accumulation factors. Due to their hydrophobicity, HOPs tend to sorb onto particles in environment. The influence of the dissolved organic matters (DOMs) on the sorption partition coefficient is observed because of their interactions with HOPs. This binding between DOM and HOPs increases apparent solubility and mobility of the HOPs in natural aquatic system. On the purpose of obtaining data closer to the real world, many aquatic factors, such as the concentration and types of DOM, pH value and ionic strength, are studied intensively recently. There are many studies about the mechanisms in the association of DOM and HOPs. Most of them assume achievement of equilibrium in their measurement. Recently, it was reported (Engebretson and von Wandruszka, 1998) that slow, revering, and even oscillating kinetics are observed. It is great concern and interest to those related studies in literatures. Complicated kinetic may in fact be a cause of the reproducibility problems for measurements of HOPs associated with both humic acid and metals. As such, by monitoring fluorescence intensity, we investigate the equilibrium kinetic of pyrene in HA solutions. In this study, results show that there are two stages of the fluorescence intensity after pyrene spiked into HA solutions: First, the fluorescence intensity decreases steeply due to the first dispersion of pyrene and the reaction of pyrene and HA (the front is dominance). Secound, fluorescence intensity decreases gently because of wall-effect. The dispersion rate of pyrene in HA solutions is difference with HA molecular size and quantity. As the ionic strength rising, cations reacting with specific binding sites on HA, the molecules¡¦ configuration of HA is changed, and less obstruct for dispersing of pyrene. It works as well as little molecular quantity. For second stage when ionic strength rising, wall- associations is less because of the hydrophobic-binding of pyrene and LHA is more stronger. Furthermore, it is not observed the ¡§migration¡¨ of Mg2+ within the LHA molecular structure as described by Engebretson and von Wandruszka .The reasons that make different results may depend on the species of humic acid. Therefore, the observations of Engebretson and von Wandruszka could not be used directly questioning those results in literatures. In addition, the effects of various cations (Mg2+, Ca2+and Sr2+) on Kdom are studied. It is believed different cation reacts with different specific binding sites on HA. As such, both charge density and affinity of cation with specific binding sites on HA should be considered in discussing the effects of metal ionic on the binding constants between PAHs and DOM.

This thesis presents a modeling program to obtain equilibrium information for a fluorescent system. Determining accurate dissociation constants for equilibrium processes involving a fluorescent mechanism can prove to be quite challenging. Typically, titration curves and non-linear least squares fitting of the data using computer programs are employed to obtain such constants. However, these approaches only consider the total fluorescence signal and often ignore other energy transfer processes within the system. The current model considers the impact on fluorescence from equilibrium binding (viz., metal-ligand, ligand-substrate, etc.), quenching and resonance energy transfer. This model should provide more accurate binding constants as well as insights into other photonic processes. The equations developed for this model are discussed and are fit to experimental data from titrimetric experiments. Since the experimental data are generally in excess of the number of parameters that are needed to define the system, fitting is operated in an overdetermined mode and employs error minimization (either absolute or relative) to define goodness of fit. Examples of how changes in certain parameters affect the shape of the titrimetric curve are also presented. The detection of metal ions is very important, causing a need for the development of a metal ion sensor that provides selectivity, sensitivity, real-time in situ monitoring, and a flexible design. In order to be able to perform in situ monitoring of trace metal ions, FRET-pair labeled peptides were attached to a Tentagel[trademark] resin surface. After soaking in nonmetal and metal solutions (pH = 7.5), the resin beads gave an enhanced response in the presence of Hg²⁺ and Zn²⁺. Using a t-test, the signals of the beads that were soaked in a solution of each of these metal ions (and that of Cd²⁺) were determined to be significantly different from beads soaked in a solution without metal. However, the standard deviation between a set the beads was too large in order to differentiate a bead that was soaked in nonmetal solution versus one soaked in a metal containing solution. / text

This thesis is an investigation of the relative differences of acid ionization constants and ion mobility in D2O versus H2O under hydrothermal conditions, for acetic acid and phosphoric acid. Values of specific conductivity were measured for each acid in H2O and D2O, as well as for a series of strong electrolytes using a high-temperature high-pressure AC conductivity flow cell that was originally designed at the University of Delaware. The Fuoss-Hsai-Fernández-Prini (FHFP) equation was fitted to the experimental values of molar conductivity, Λ, to obtain molar conductivities at infinite dilution, Λo. The molar conductivities at infinite dilution for each acid were used to calculate degrees of dissociation and ionization constants in D2O versus H2O from 298 K to 571 K. Measured values of differences in pKaq in D2O vs H2O, ΔpKaq = [pKaq,D2O – pKaq,H2O], become relatively independent of temperature above 423 K, with values of: ΔpKaq 0.45 for acetic acid and ΔpKaq 0.35 for phosphoric acid. The Density Model was then fitted to the values of pKaq in H2O and D2O to represent their temperature dependence to a precision of ± 0.01 in ΔpKaq. Comparisons of the molar conductivities and ionic molar conductivities at infinite dilution for the strong electrolytes in H2O and D2O as a function of temperature have also been made, based on Walden’s rule correlations, (λ°•η)D2O / (λ°•η)H2O. Changes in values of (λ°•η)D2O / (λ°•η)H2O as a function of temperature are consistent with a change in the relative hydration behavior of ions, where the effective Stokes’ radii of the ions in D2O versus H2O changes at temperatures above ~ 450 K. Changes in values of (λ°•η)D2O / (λ°•η)H2O for D+/H+ and OD-/OH- suggest that proton hopping “Grotthuss” mechanisms become more efficient in D2O versus H2O with increasing temperature. / University Network of Excellence in Nuclear Engineering, Ontario Power Generation Ltd, Natural Science and Engineering Research Council of Canada