Showing papers by "University of Wisconsin–Eau Claire published in 1997"
TL;DR: In this paper, the authors demonstrate that under certain positive ion mode electrospray-mass spectrometry (ES-MS) conditions, solution pH may be decreased significantly (by at least 4 pH units) as a result of the electrolytic oxidation of water in ES-MS.
200 citations
TL;DR: The authors compared the ethical beliefs, preferred ethical ideology and degree of Machiavellianism of US versus Egyptian consumers and found that while US consumers appear generally less likely to accept various questionable consumer practices than Egyptian consumers, they are more likely to reject moral absolutes.
Abstract: In recent years, business ethics has drawn increased interest from business and marketing practitioners as well as from academicians. Despite the repeated call in the literature for cross‐cultural research in this age of globalization, virtually no studies have examined the ethical beliefs and ideologies of foreign consumers and compared them to those of US consumers. Investigates the ethical beliefs, preferred ethical ideology and degree of Machiavellianism of US versus Egyptian consumers. Concludes that while US consumers appear generally less likely to accept various questionable consumer practices than Egyptian consumers, they are more likely to reject moral absolutes.
183 citations
TL;DR: In this paper, ground-penetrating radar (GPR) was used to image the internal structural of the gravelly Peyto Creek delta in Banff National Park, Alberta, Canada.
81 citations
TL;DR: In this article, it was shown that two different types of spectral emission are generally produced in gamma-ray bursts and that both types of emission are common in many bursts, demonstrating that a single source object is capable of generating both of them.
Abstract: It is shown in this study that two different types of spectral emission are generally produced in gamma-ray bursts A subset of bursts is identified that exhibits a marked lack of fluence above 300 keV, and these bursts are shown to have luminosities about an order of magnitude lower than bursts with significant fluence above 300 keV The bursts lacking emission above 300 keV exhibit an effectively homogeneous intensity distribution In addition, it is shown that both types of emission are common in many bursts, demonstrating that a single source object is capable of generating both of them These results strongly favor a gamma-ray burst source object that produces two different types of emission with varying degrees of superposition The impact of this behavior is strong enough that it affects the properties of the burst intensity distribution, as well as the burst spectral characteristics
74 citations
TL;DR: In this article, two empirical models are used to implement the arbitrage pricing theory: the factor loading model (FLM) and the macrovariable model (MVM) to explain real estate returns using equity REIT returns as a proxy.
Abstract: Two empirical models are used to implement the arbitrage pricing theory: the factor loading model (FLM) and the macrovariable model (MVM). This study compares the ability of these two models to explain real estate returns using equity REIT returns as a proxy. Two tests are performed: a comparison of crosssectional adjusted-R2's and the Davidson and Mackinnon test. The results show that while the two models perform equally well during the period 1974–1979, the MVM outperforms the FLM over the periods 1980–1985 and 1986–1991. In addition, both models suggest superior financial performance for EREITs relative to other investments in the market during the period 1980–1985.
73 citations
TL;DR: For instance, the authors argued that race fulfilled Europe's ideological needs by creating the illusion that human difference was biologically ordained, and pointed out that non-Europeans were not the sole inventors of race.
Abstract: SCHOLARS WORKING ON THE HISTORY OF RACE AS AN IDEA assume that Europeans were the sole inventors of it. 1 Undeniably, race (the belief that people can be categorized by observable physical differences such as skin color) flourished with the early modern European slave trade. Sometime in the eighteenth century, race outpaced the older categories of Christian and pagan to become the primary justification for expropriating the land and labor of others. As a system of categorizing people, race fulfilled Europe's ideological needs by creating the illusion that human difference was biologically ordained.2 But, as Europeans spun their web of racial hierarchies, what were non-Europeans thinking about race? Historians have yet to tackle this question in depth, instead focusing on how whites constructed images of others.3 This approach to the historical emergence of race as a system for categorizing people replicates what it purports to critique, since the emphasis on European image-making consigns American Indians and other non-white peoples to a passive role in the construction of knowledge. They exist only as the objects of white observation, and the power to label or name resides with Europeans. One example of this tendency is the standard explanation for how Indians got to be "red": European explorers saw that Indians wore red paint and so called them
70 citations
TL;DR: Differences in effectiveness existed between the IT and PMR groups; the pain and distress scores were lower in the PMR group.
Abstract: The purpose of this study was to determine if Therapeutic Touch (TT) decreased pain in elders with degenerative arthritis, compared with routine treatment and progressive muscle relaxation (PMR). Eighty-two noninstitutionalized subjects, age 55 or older, were randomly assigned to TT or PMR treatments. Subjects served as their own controls for 4 weeks and then received six treatments at 1-week intervals. Visual analogue scales (VAS) for pain intensity and distress were used. Significant differences from baseline to postsixth treatment were found within groups. TT decreased pain (t(46) = 7.60, p = < .001) and distress (t(44) = 7.08, p = < .001). PMR decreased pain (t(36) = 6.58, p = .005) and distress (t(36) = 6.90, p = < .001). Differences in effectiveness existed between the TT and PMR groups; the pain and distress scores were lower in the PMR group. The differences approached significance for pain, F(2, 76) = 2.8, p = .06, and were significant for distress, F(2, 75) = 5.6, p = .005.
64 citations
TL;DR: In this article, the ground state of the lithium atom has been studied for high precision calculations and the following properties are considered: upper and lower bounds to the nonrelativistic ground state energy, the specific mass shift, the transition isotope shift, relativistic corrections to the ground states energy, Lamb shift, ionization potential, electron affinity, hyperfine coupling constant, the nuclear magnetic shielding constant, diamagnetic susceptibility, several polarizability factors, shielding constants, oscillator strength sums, the electron density and spin density, intracule functions, moments �
Abstract: Progress on high precision calculations for the ground state of atomic lithium is reviewed. The following properties are considered: upper and lower bounds to the nonrelativistic ground state energy, the specific mass shift, the transition isotope shift, relativistic corrections to the ground state energy, the Lamb shift, the ionization potential, the electron affinity, the hyperfine coupling constant, the nuclear magnetic shielding constant, the diamagnetic susceptibility, several polarizability factors, shielding constants, oscillator strength sums, the electron density and spin density, intracule functions, moments 〈rin〉 and 〈rijn〉 and form factors. A discussion is also given on some convergence considerations as they apply to high precision calculations on the lithium atom.
59 citations
TL;DR: In this article, the photocatalytic deposition of silver from ethanol solution on TiO2 nanoparticles prepared with a chemisorbed surface alkoxide layer has been examined in real time by picosecond-resolved transient absorption spectroscopy.
Abstract: The photocatalytic deposition of silver from ethanol solution on TiO2 nanoparticles prepared with a chemisorbed surface alkoxide layer has been examined in real time by picosecond-resolved transient absorption spectroscopy. This photocatalyst formation of surface-trapped photoelectron states, hypothesized to be Ti(III), can be followed on the time scale of the experiment (≤10 ns). Loss of these electrons to recombination is inconsequential, presumably owing to sacrificial hole trapping by the surface alkoxide states. Silver deposition occurs on the same time scale, and the pseudo-first-order rate constant for growth of the silver(0) transient absorption is the same as for the disappearance of the Ti(III) states under these conditions. We infer that one-electron, inner sphere reduction of Ag(I) by Ti(III) is rate determining in the formation of the colloidal silver deposit. These particles must accordingly grow by a sequence of alternating electronic and ionic events analogous to those hypothesized to be i...
58 citations
TL;DR: Consideration of the differences to be expected in the internal strains of the various possible conformations of the two oxidation states leads to the hypothesis that these Cu(II/I) systems may actually involve a three-rung ladder mechanism rather than a simple square scheme, although it is doubtful that more than two rungs will ever be experimentally observable.
Abstract: Variable-temperature slow- and rapid-scan cyclic voltammetry has been applied in a solvent system of 80% methanol−20% water (w/w) to both the Cu(II) and Cu(I) complexes formed with a series of five...
50 citations
TL;DR: For instance, the authors found that women with high leuels of sexual guilttend to perceive less sexual arousal, resulting in less enjoyment from their sexual encounters, while women with low levels of sexual arousal perceived less sexual satisfaction.
Abstract: First sexual intercourse is often viewed as a rite of passage to adulthood. While one's initial coital experience may lead to affirmation of self identity, it is disappointing for many, resulting an feelings of guilt and shame. If guilt feelings do emerge, the likelihood of future sexual dissatisfaction is greatly increased. In particular, women with high leuels of sexual guilttend to perceive less sexual arousal, resulting in less enjoyment from their sexual encounters. The purposes of this investigation were to identify those factors crrelated with feeling guilty about first sexual intercourse and to examine the injuence of guilt about first intercourse on current sexual satisfaction. An anonymous questionnaire was administered to never–married collegewomen, with the subsample for this investigation consisting of 570 women. Significant variables correlated with guilt at first sexual intercourse include uncommunicative mother and father figures, overstrict father figures, uncomfortabkness with s...
TL;DR: This paper argued that social welfare programs promote or suppress ethnic organizations depending on how they affect an ethnic community's institutional completeness and contrasted with ethnic competition and resource mobilization explanations for the formation of ethnic organizations.
Abstract: The expansion of the welfare state during the 20th century has altered the conditions shaping the formation of ethnic organizations. Drawing upon research in the divergent fields of social policy, immigrant communities, and social movements, this article argues that social welfare programs promote or suppress ethnic organizations depending on how they affect an ethnic community's institutional completeness. This welfare state channeling theory is contrasted with ethnic competition and resource mobilization explanations for the formation of ethnic organizations. An analysis of 800 Indochinese refugee associations finds that public assistance has no effect on the prevalence of these organizations, but that privatization of federal social service expenditures does, thus partially supporting the welfare state channeling theory.
TL;DR: Fluorescence quantum yields and emission lifetimes have been measured at room temperature for a series of thiacarbocyanine dyes in various alcohol solvents as mentioned in this paper, and all radiationless deactivation events ar
Abstract: Fluorescence quantum yields and emission lifetimes have been measured at room temperature for a series of thiacarbocyanine dyes in various alcohol solvents. All radiationless deactivation events ar...
TL;DR: Fossil cryptospore dyads consistent with published descriptions of Dyadospora murusattenuata fall into two general categories when examined with the TEM as discussed by the authors, and have a wall consisting of an outer homogeneous layer that is present on non-contact surfaces, but absent in large part over the contact surface, a middle layer composed of plate-shaped units, and an innermost granular layer.
TL;DR: In this paper, ground penetrating radar (GPR) reflection paterns from the modern and avulsed channel are used to reconstruct and interpret the fluvial architecture of the Avulsed Channel deposits.
Abstract: Near Aoste, France, an avulsion shifted the Rhone River from a southwesterly course through the valley of the Marais des Avenieres to its present northwesterly course in the Basses Terres. Ground penetrating radar (GPR) reflection paterns from the modern and avulsed channel are used to reconstruct and interpret the fluvial architecture of the avulsed channel deposits.
A grid of GPR lines was run across and along the avulsed course of the Rhone. The radar reflections have impressive continuity and, for the most part, horizontal to gentle dips (1–2°); although, in places, the reflections have steeper dips (averaging 6°), which are often accompanied by mound-like reflection patterns. Draped over or stacked adjacent to the mounds are packages of dipping reflections which form an en echelon stacking pattern, which is interpreted as being produced by the downstream growth of gravel bars. The cross-valley profiles are composed of stacked concave reflections which are laterally continuous with dips that vary from 1° to a maximum of 8° along the flanks of the concavities. The complete assemblage of these multistoried concave reflection patterns is interpreted as a suite of complete or partial channel fills.
The coarse-grained sediments of the pre-avulsion Rhone probably represents a transitional phase between a coarse-grained, chute-modified meandering depositional system and a wandering gravel-bed river depositional style. © 1997 by John Wiley & Sons, Ltd.
Book•
01 Jan 1997TL;DR: Romines as mentioned in this paper explores the relationship between mother and daughter working as collaborative authors and calls into question our assumptions about plot, juvenile fiction, and constructions of gender on the nineteenth-century frontier and in the Depression years when the Little House books were written.
Abstract: With more than thirty-five million copies in print, the Little House series, written in the 1930s and 1940s by Laura Ingalls Wilder and her daughter, Rose Wilder Lane, has been a spectacular commercial success. What is it about this eight-volume serial novel for children that accounts for its enduring power? And what does the popularity of these books tell us about the currents of American culture? Ann Romines interweaves personal observation with scholarly analysis to address these questions. Writing from a feminist perspective and drawing on the resources of gender studies, cultural studies, and new historicist reading, she examines both the content of the novels and the process of their creation. She explores the relationship between mother and daughter working as collaborative authors and calls into question our assumptions about plot, juvenile fiction, and constructions of gender on the nineteenth-century frontier and in the Depression years when the Little House books were written. This is a book that will appeal both to scholars and to general readers who might welcome an engaging and accessible companion volume to the Little House novels.
TL;DR: The MENC (1990) Future Directions Statement directs music educators to ''increase the amount and quality of music education in preschools, day care centers, and kindergartens'' as discussed by the authors.
Abstract: During the past ten years, increasing interest in the welfare of the preschool child has led music education organizations and teachers to examine their own philosophies and practices concerning music in the life of the young child. The MENC (1990) Future Directions Statement directs music educators to \"increase the amount and quality of music education in preschools, day care centers, and kindergartens.\" Implicit in this goal is the assumption that the amount and quality of music in such settings are known. During this same decade, early childhood organizations have acknowledged the importance of music in defining developmentally appropriate practice for young children as that which includes experience in singing, listening to music of various cultures, and moving and engaging in rhythmic play with simple rhythm instruments (Bredenkamp, 1987). These recommendations take the form of policy when articulated as accredited standards to address curriculum and selection of activities emphasizing \"creative expression and appreciation for the arts\" (National Association for the Education of Young Children, 1991, p. 23). The extent to which these policies are considered or
TL;DR: Modifications in the structure and composition of the 105Rh-thia macrocycle complexes produce significant differences in their uptake and retention in both the liver and kidneys, demonstrating less kidney retention and decreased retention of activity in the kidneys.
TL;DR: In this article, the second-order rate constants k12(obsd) measured at 25 °C in acetonitrile by stopped-flow for 47 electron transfer (ET) reactions among ten tetraalkylhydrazines, four ferrocene derivatives, and three p-phenylenediamine derivatives are discussed.
Abstract: Second-order rate constants k12(obsd) measured at 25 °C in acetonitrile by stopped-flow for 47 electron transfer (ET) reactions among ten tetraalkylhydrazines, four ferrocene derivatives, and three p-phenylenediamine derivatives are discussed. Marcus's adiabatic cross rate formula k12(calcd) = (k11 k22 k12 f12)1/2, ln f12 = (ln K12)2/4 ln(k11k22/Z2) works well to correlate these data. When all k12(obsd) values are simultaneously fitted to this relationship, best-fit self-exchange rate constants, kii(fit), are obtained that allow remarkably accurate calculation of k12(obsd); k12(obsd)/k12‘(calcd) is in the range of 0.55−1.94 for all 47 reactions. The average ΔΔGij between observed activation free energy and that calculated using kii(fit) is 0.13 kcal/mol. Simulations using Jortner vibronic coupling theory to calculate k12 using parameters which produce the wide range of kii values observed predict that Marcus's formula should be followed even when V is as low as 0.1 kcal/mol, in the weakly nonadiabatic region. Tetracyclohexylhydrazine has a higher kii than tetraisopropylhydrazine by a factor of ca. 10. Replacing the dimethylamino groups of tetramethyl-p-phenylenediamine by 9-azabicyclo[3.3.1]nonyl groups has little effect on kii, demonstrating that conformations which have high intermolecular aromatic ring overlap are not necessary for large ET rate constants. Replacing a γ CH2 group of a 9-azabicyclo[3.3.1]nonyl group by a carbonyl group lowers kii by a factor of 17 for the doubly substituted hydrazine and by considerably less for the doubly substituted p-phenylenediamine.
TL;DR: In this article, the authors developed the necessary weighting for the line detection probability for each spectrum spanning the burst, and identified the bursts in which lines are most likely to be detected.
Abstract: The physical importance of the apparent discrepancy between the detections by pre-BATSE missions of absorption lines in gamma-ray burst spectra and the absence of a BATSE line detection necessitates a statistical analysis of this discrepancy. This analysis requires a calculation of the probability that a line, if present, will be detected in a given burst. However, the connection between the detectability of a line in a spectrum and in a burst requires a model for the occurrence of a line within a burst. We have developed the necessary weighting for the line detection probability for each spectrum spanning the burst. The resulting calculations require a description of each spectrum in the BATSE database. With these tools, we identify the bursts in which lines are most likely to be detected. Also, by assuming a small frequency with which lines occur, we calculate the approximate number of BATSE bursts in which lines of various types could be detected. Lines similar to the Ginga detections can be detected in relatively few BATSE bursts; for example, in only ~20 bursts are lines similar to the GB 880205 pair of lines detectable. Ginga reported lines at ~20 and ~40 keV, whereas the low-energy cutoff of the BATSE spectra is typically above 20 keV; hence BATSE's sensitivity to lines is less than that of Ginga below 40 keV, and greater above. Therefore, the probability that the GB 880205 lines would be detected in a Ginga burst rather than a BATSE burst is ~0.2. Finally, we adopt a more appropriate test of the significance of a line feature.
TL;DR: Describing the level of religious well-being and selected characteristics of religiosity in a sample of 114 non-institutionalized, largely rural elderly women and identified that religious beliefs become increasingly important with age will strengthen the scope of health care practice for elderly women.
Abstract: Spirituality is recognized as an important component of health care practice with elderly people. Yet, discussion of the role it plays in elderly women on a day‐to‐day basis is minimal, and it is frequently not addressed in quality‐of‐life studies in this population. The purposes of this study were to describe the level of religious well‐being and selected characteristics of religiosity in a sample of 114 non‐institutionalized, largely rural elderly women (Mdn age = 75), as well as to identify the relationship between selected factors and the level of religious well‐being. Descriptive research revealed a high level of religious well‐being among the participants and significant positive correlation between religious well‐being and the variables of social support and hope (p < .001). Through stepwise multiple regression, hope emerged as the single significant predictor of religious well‐being (p < .001), explaining 31% of the variance in the dependent variable. The majority of respondents reported regularly...
TL;DR: A caring, health-promotion philosophy of practice, rather than an institutional philosophy of cure and treatment, may more actively support and enhance clients' hope among noninstitutionalized elderly.
TL;DR: In this article, the authors developed the necessary weighting for the line detection probability for each spectrum spanning the burst, and identified the bursts in which lines are most likely to be detected.
Abstract: The physical importance of the apparent discrepancy between the detections by pre-BATSE missions of absorption lines in gamma-ray burst spectra and the absence of a BATSE line detection necessitates a statistical analysis of this discrepancy. This analysis requires a calculation of the probability that a line, if present, will be detected in a given burst. However, the connection between the detectability of a line in a spectrum and in a burst requires a model for the occurrence of a line within a burst. We have developed the necessary weighting for the line detection probability for each spectrum spanning the burst. The resulting calculations require a description of each spectrum in the BATSE database. With these tools we identify the bursts in which lines are most likely to be detected. Also, by assuming a small frequency with which lines occur, we calculate the approximate number of BATSE bursts in which lines of various types could be detected. Lines similar to the Ginga detections can be detected in relatively few BATSE bursts; for example, in only ~20 bursts are lines similar to the GB 880205 pair of lines detectable. Ginga reported lines at ~20 and ~40 keV whereas the low energy cutoff of the BATSE spectra is typically above 20 keV; hence BATSE's sensitivity to lines is less than that of Ginga below 40 keV, and greater above. Therefore the probability that the GB 880205 lines would be detected in a Ginga burst rather than a BATSE burst is ~0.2. Finally, we adopted a more appropriate test of the significance of a line feature.
TL;DR: In this article, the electron transfer reactions of five copper(II/I) complexes involving ligands in which either a benzene or a cyclohexane ring, or both, have been substituted into the ligand backbone of the 14-membered tetrathiamacrocycle [14]aneS4.
Abstract: Kinetic studies have been conducted in acetonitrile on the electron-transfer reactions of five copper(II/I) complexes involving ligands in which either a benzene or a cyclohexane ring, or both, have been substituted into the ligand backbone of the 14-membered tetrathiamacrocycle [14]aneS4. The specific ligands utilized in this work include 2,3-benzo-1,4,8,11-tetrathiacyclotetradecane (bz-[14]aneS4), 2,3-trans-cyclohexano-1,4,8,11-tetrathiacyclotetradecane (trans-cyhx-[14]aneS4), 2,3-benzo-9,10-trans-cyclohexano-1,4,8,11-tetrathiacyclotetradecane (bz,trans-cyhx-[14]aneS4), 2,3-benzo-9,10-cis-cyclohexano-1,4,8,11-tetrathiacyclotetradecane (bz,cis-cyhx-[14]aneS4), and 2,3-cis-9,10-trans-dicyclohexano-1,4,8,11-tetrathiacyclotetradecane (cis, trans-dicyhx-[14]aneS4). Each CuII/IL system has been reacted with three separate reducing agents and three separate oxidizing agents to examine the effect of driving force upon the kinetic parameters. The Marcus relationship has been applied to each cross-reaction rate c...
TL;DR: Cost and caring are both dimensions of holistic nursing practice; nurses need to examine the specific embedded assumptions of cost and caring; measure each; and demonstrate their inter-relationship and effects on patient outcomes.
Abstract: Cost and caring are both dimensions of holistic nursing practice. Each is a term that is complex and ambiguous yet assumed to be simple and well understood. Nurses need to examine the specific embedded assumptions of cost and caring; measure each; and demonstrate their inter-relationship and effects on patient outcomes. Integral to caring is "professional vigilance," which cannot be delegated; attempts to do so may incur future hidden costs. Nurses are urged to be alert to cost-shifting that affects caring and quality. Advocacy for cost-effective caring practices is urged through participation in governance structures.
TL;DR: This article found that interpersonal conflicts in the workplace frequently involve conversations with coworkers and outsiders as a means of making sense of the conflict situation, but little is known about the de facto co-occurrence of these conversations.
Abstract: Interpersonal conflicts in the workplace frequently involve conversations with coworkers and outsiders as a means of making sense of the conflict situation. However, little is known about the facto...
TL;DR: There is sufficient evidence for the creation of a new role: advanced practice nurse in palliative care, and the author maintains that the field of nursing would be diminished if the need were ignored.
Abstract: The terminally ill are emerging as a specialized patient population that needs the expanded skills and knowledge of advanced practice nurses. These nurses can follow patients across a variety of settings in an integrated system of health care and over the continuum of living and dying. This paper addresses the concept of palliative care and the advantages of advanced practice nurse leadership in this area. Four major criteria for the establishment of a new advanced practice nursing area (American Nurses Association, 1995) serve as a framework. These criteria are: the area lies within the scope of nursing practice; a documented need exists; there is a body of knowledge upon which to base the practice; and the field of nursing would be diminished if the need were ignored. The author maintains that there is sufficient evidence for the creation of a new role: advanced practice nurse in palliative care.
TL;DR: Investigating the impact of a growers' application of an insecticide upon populations of aphids and their arthropod predators in a plantation in western Wisconsin indicates that insecticide treatment of the shoot-feeding stages (fundatrigenia and sexuparae) can reduce numbers of aphid and their predators in the current and subsequent year, but will not necessarily reduce needle damage.
Abstract: The balsam twig aphid, Mindarus abietinus Koch, is a pest of balsam fir, Abies balsamea (L.) Mill., and Fraser fir, Abies fraseri (Pursh) Poir., Christmas trees. This study evaluated the impact of a growers' application of an insecticide (Phosphamidon-8) upon populations of aphids and their arthropod predators (Coccinellidae larvae and adults, Syrphidae larvae, Chrysopidae and Hemerobiidae larvae) in a plantation in western Wisconsin. Spraying occurred on 27 May 1994 as a result of aphids (fundatrigenia and sexuparae) visibly damaging Christmas trees targeted for December 1994 sales. Aphids and predators were sampled by visual counts of infested shoots before and after insecticide treatment. Percentages of treated aphid-infested shoots significantly decreased from 86% prespray to 3% postspray, whereas percentages of untreated infested shoots increased from 75-88%. Two weeks postspray, percentages of both sprayed and unsprayed infested shoots were 5%. Numbers of aphidophagous predators significantly decreased on sprayed trees and significantly increased on unsprayed trees. Spiders increased on all trees. Assessment of needle damage 9 mo after treatment revealed no significant differences in the mean number of damaged shoots between sprayed and unsprayed trees. However, during the following growing season, treated trees contained significantly less numbers of aphids and predators than did unsprayed trees. This indicates that insecticide treatment of the shoot-feeding stages (fundatrigenia and sexuparae) can reduce numbers of aphids and their predators in the current and subsequent year, but will not necessarily reduce needle damage.
TL;DR: Application of the Marcus relationship to the experimentally determined cross-reaction rate constants yielded self-exchange rate constants for all four Cu(II/I)L acyclic systems which were relatively constant for both oxidation and reduction under a wide range of conditions.
Abstract: The kinetics of a series of Cu(II/I)-acyclic tetrathiaether complexes reacting with several oxidizing and reducing reagents have been examined in aqueous solution at 25 degrees C. This investigation has included a re-examination of Cu(II/I)(Me(2)-2,3,2-S(4)) (Me(2)-2,3,2-S(4) = 2,5,9,12-tetrathiatridecane = L12a), containing the ethylene-trimethylene-ethylene bridging sequence, plus three newly synthesized ligands containing an alternate bridging sequence of trimethylene-ethylene-trimethylene: 2,6,9,13-tetrathiatetradecane (Me(2)-3,2,3-S(4) = L12b) and two cyclohexanediyl-substituted derivatives, viz., cis-1,2-bis[(3-methylthiopropyl)thio]cyclohexane (cis-cyhx-Me(2)-3,2,3-S(4) = L14) and trans-1,2-bis[(3-methylthiopropyl)thio]cyclohexane (trans-cyhx-Me(2)-3,2,3-S(4) = L15). The corresponding phenylene derivative, 1,2-bis[(3-(methylthio)propyl)thio]benzene (bz-Me(2)-3,2,3-S(4) = L13), was also synthesized but did not form a measurable copper complex. The conditional stability constants for Cu(II)L (K(Cu)()II(L)(')) and Cu(I)L (K(Cu)()I(L)(')) and the Cu(II/I)L formal redox potentials (E(f)) vs NHE at 25 degrees C (generally at m = 0.10 (NaClO(4))) are as follows: for L12b, 15 M(-)(1), 1.0 x 10(13) M(-)(1), 0.83 V; for L14, 2.8 x 10(2) M(-)(1), 0.9(5) x 10(13) M(-)(1), 0.75 V; for L15, 8.8 x 10(2) M(-)(1), 6.(3) x 10(13) M(-)(1), 0.77 V. Application of the Marcus relationship to the experimentally determined cross-reaction rate constants yielded self-exchange rate constants for all four Cu(II/I)L acyclic systems which were relatively constant for both oxidation and reduction under a wide range of conditions. This contrasts sharply with previous results obtained for corresponding macrocyclic ligand systems.