scholarly journals The Stoichiometric Uniqueness of Multiple Chemical Reaction Systems in Chemical Thermodynamics, Kinetics and Catalysis – Contributions of Professor Ilie Fishtik

2020 ◽  
Vol 15 (2) ◽  
pp. 7-28
Author(s):  
Igor Povar
Keyword(s):  
Chemical Reactions ◽  
Chemical Species ◽  
Chemical Thermodynamics ◽  
Worcester Polytechnic Institute ◽  
University Of Iowa ◽  
Reaction Systems ◽  
Kinetic Mechanisms ◽  
New Type ◽  
Fundamental Equations ◽  
The University

The main scientific achievements of great significance accomplished by Professor Ilie Fishtik at the University of Iowa and the Worcester Polytechnic Institute, in several fields of the physical chemistry as chemical thermodynamics, kinetics and heterogeneous catalysis were revealed and briefly analysed. Fundamental equations of chemical thermodynamics within the De Donder (stoichiometric) approach were reformulated in terms of a special class of chemical reactions, called as response reactions. Using this approach, the unusual behaviour of chemical equilibrium systems, to interpret the apparent contradictions to Le Chatelier principle and to discover hitherto unnoticed thermodynamic identities, was rationalised. The stabilities of chemical species were formulated in terms of a certain class of stoichiometrically unique chemical reactions and their thermochemical characteristics. A completely new approach for the generation and simplification of kinetic mechanisms for complex reaction systems was developed and applied. Based on a new type of reaction networks, referred to as reaction route graphs, a systematic method of analysis and reduction of a microkinetic mechanism was established and employed.

Thermodynamics of chemical reactions

2005 ◽  
Author(s):  
Boris S. Bokstein ◽  
Mikhail I. Mendelev ◽  
David J. Srolovitz
Keyword(s):  
Free Energy ◽  
Gibbs Free Energy ◽  
Chemical Reactions ◽  
Chemical Reaction ◽  
Chemical Equilibrium ◽  
Chemical Species ◽  
Chemical Thermodynamics ◽  
Chemical Equation ◽  
Definition Of ◽  
The Right

This chapter is devoted to chemical equilibrium. We will use thermodynamics to answer two main questions: (1) ‘‘In which direction will a chemical reaction proceed?’’ and (2) ‘‘What is the composition of the system at equilibrium?’’ These are the oldest and most important questions in all of chemical thermodynamics for obvious reasons. The answers to these questions represent the foundation upon which all modern chemical technologies rest. Consider the following chemical reaction: . . . aA = bB ⇆ cC + dD. (5.1) . . . A, B, C, and D represent the chemical species participating in the reaction and a, b, c, and d are the stoichiometric coefficients of these species. We refer to the species on the left side of this chemical equation as reactants and those on the right as products. The reaction in Eq. (5.1) can either go forward, from left to right (reactants to products), or backward, from right to left (products to reactants). Therefore, we see that the definition of which we call reactants and which products is arbitrary. Assume that Eq. (5.1) occurs at constant temperature and pressure. Under these conditions, the direction of the reaction is determined by the sign of the change of the Gibbs free energy.

The consolidation of microscopy technology into a university research support facility: Reflections on the 1980's and projections for the 1990's at the university of iowa

1993 ◽  
Vol 51 ◽  
pp. 476-477
Author(s):  
Kenneth C. Moore
Keyword(s):  
Laser Scanning ◽  
Freeze Fracture ◽  
Freeze Substitution ◽  
Research Support ◽  
University Of Iowa ◽  
Staff Members ◽  
The Past ◽  
Research Grade ◽  
The University ◽  
Support Facility

The University of Iowa Central Electron Microscopy Research Facility(CEMRF) was established in 1981 to support all faculty, staff and students needing this technology. Initially the CEMRF was operated with one TEM, one SEM, three staff members and supported about 30 projects a year. During the past twelve years, the facility has replaced all instrumentation pre-dating 1981, and now includes 2 TEM's, 2 SEM's, 2 EDS systems, cryo-transfer specimen holders for both TEM and SEM, 2 parafin microtomes, 4 ultamicrotomes including cryoultramicrotomy, a Laser Scanning Confocal microscope, a research grade light microscope, an Ion Mill, film and print processing equipment, a rapid cryo-freezer, freeze substitution apparatus, a freeze-fracture/etching system, vacuum evaporators, sputter coaters, a plasma asher, and is currently evaluating scanning probe microscopes for acquisition. The facility presently consists of 10 staff members and supports over 150 projects annually from 44 departments in 5 Colleges and 10 industrial laboratories. One of the unique strengths of the CEMRF is that both Biomedical and Physical scientists use the facility.

Five Decades of Research Experience in Speech Anatomy and Physiology

2016 ◽  
Vol 1 (5) ◽  
pp. 4-12
Author(s):  
David P. Kuehn
Keyword(s):  
Ohio State University ◽  
State University ◽  
Research Experience ◽  
University Of Iowa ◽  
University Of Illinois ◽  
Anatomy And Physiology ◽  
The Ohio State University ◽  
Speech Science ◽  
The University ◽  
East Carolina University

This report highlights some of the major developments in the area of speech anatomy and physiology drawing from the author's own research experience during his years at the University of Iowa and the University of Illinois. He has benefited greatly from mentors including Professors James Curtis, Kenneth Moll, and Hughlett Morris at the University of Iowa and Professor Paul Lauterbur at the University of Illinois. Many colleagues have contributed to the author's work, especially Professors Jerald Moon at the University of Iowa, Bradley Sutton at the University of Illinois, Jamie Perry at East Carolina University, and Youkyung Bae at the Ohio State University. The strength of these researchers and their students bodes well for future advances in knowledge in this important area of speech science.

Rheometers, Bioreactors, and Vocalization Forces: Using Basic Science Investigations to Help the Voices of Teachers

2008 ◽  
Vol 18 (3) ◽  
pp. 119-125
Author(s):  
Sarah Klemuk
Keyword(s):  
Basic Science ◽  
Tissue Growth ◽  
University Of Iowa ◽  
Support Cell ◽  
Rest Periods ◽  
Collaborative Studies ◽  
Professional Voice Users ◽  
The University ◽  
Science Investigations ◽  
Professional Voice

Abstract Collaborative studies at the University of Iowa and the National Center for Voice and Speech aim to help the voices of teachers. Investigators study how cells and tissues respond to vibration doses simulating typical vocalization patterns of teachers. A commercially manufactured instrument is uniquely modified to support cell and tissue growth, to subject tissues to vocalization-like forces, and to measure viscoelastic properties of tissues. Through this basic science approach, steps toward safety limits for vocalization and habilitating rest periods for professional voice users will be achieved.

The Kontakte Multimedia Project at The University of Iowa

2013 ◽  
Vol 17 (1) ◽  
pp. 25-42 ◽  
Author(s):  
James P. Pusack
Keyword(s):  
University Of Iowa ◽  
The University

Evaluation of positive and negative symptoms in schizophrenia

1986 ◽  
Vol 1 (2) ◽  
pp. 108-122 ◽  
Author(s):  
Nancy C. Andreasen ◽  
William M. Grove
Keyword(s):  
Negative Symptoms ◽  
The United States ◽  
Psychotic Symptoms ◽  
Positive Symptoms ◽  
University Of Iowa ◽  
Normal Functions ◽  
Subsequent Investigation ◽  
The University ◽  
The Relationship ◽  
Positive And Negative Symptoms

SummaryMost investigators concur that schizophrenia is probably a heterogeneous group of disorders that share the common features of psychotic symptoms, partial response to neuroleptics, and a relatively poor outcome. The subdivision of schizophrenia into two subtypes, positive versus negative, has achieved wide acceptance throughout the world during recent years. This distinction has heuristic and theoretical appeal because it unites phenomenology, pathophysiology, and etiology into a single comprehensive hypothesis.In spite of its wide appeal, the distinction has a number of problems. These include the failure to distinguish between symptom syndromes and diseases; failure to deal with the mixed patient; failure to take longitudinal course into account; and failure to address conceptually and methodologically the distinction between positive and negative symptoms.This paper focuses primarily on the conceptual basis for two instruments designed to measure positive and negative symptoms, the Scale for the Assessment of Negative Symptoms (SANS) and the Scale for the Assessment of Positive Symptoms (SAPS), originally described in 1982. Since their description, these scales have been used in a variety of other centers. These scales are based on the hypothesis that negative symptoms represent a deficit or diminution in normal psychological functions wliile positive symptoms represent an excess or distortion of normal functions. Reliability data are now available from Italy, Spain, and Japan which suggest that these scales can be used reliably in cultural settings outside the United States. The results of these studies are summarized in this paper. In addition, a replication study involving a new sample of 117 schizophrenics collected at the University of Iowa is described. In this second study of the SANS and SAPS, internal consistency is found to be quite high in the SANS. Thus negative symptoms appear to be more internally correlated with one another than are positive symptoms. The implications of this result are discussed. A principal components analysis is used to explore the relationship between positive and negative symptoms. While the study reported in 1982 suggested that positive and negative symptoms are negatively correlated, in the present study they appear to be uncorrelated. Overall, the results suggest that the SANS and SAPS are useful comprehensive instruments for the evaluation of positive and negative symptoms. The relationship between these symptoms and external validators such as cognitive functioning or CT scan abnormalities will be reported in a subsequent investigation.

scholarly journals Chemical and biochemical thermodynamics reunification (IUPAC Technical Report)

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Antonio Sabatini ◽  
Marco Borsari ◽  
Gerard P. Moss ◽  
Stefano Iotti
Keyword(s):  
Chemical Reactions ◽  
Atp Hydrolysis ◽  
Joint Commission ◽  
Chemical Thermodynamics ◽  
Thermodynamic Quantities ◽  
Biochemical Reactions ◽  
Mathematical Transformation ◽  
Biochemical Nomenclature ◽  
Thermodynamic Potentials ◽  
Technical Report

AbstractAccording to the 1994 IUBMB-IUPAC Joint Commission on Biochemical Nomenclature (JCBN) on chemical and biochemical reactions, two categories of thermodynamics, based on different concepts and different formalisms, are established: (i) chemical thermodynamics, which employ conventional thermodynamic potentials to deal with chemical reactions [1], [2], [3]; and (ii) biochemical thermodynamics, which employ transformed thermodynamic quantities to deal with biochemical reactions based on the formalism proposed by Alberty [4], [5], [6], [7]. We showed that the two worlds of chemical and biochemical thermodynamics, which so far have been treated separately, can be reunified within the same thermodynamic framework. The thermodynamics of chemical reactions, in which all species are explicitly considered with their atoms and charge balanced, are compared with the transformed thermodynamics generally used to treat biochemical reactions where atoms and charges are not balanced. The transformed thermodynamic quantities suggested by Alberty are obtained by a mathematical transformation of the usual thermodynamic quantities. The present analysis demonstrates that the transformed values for ΔrG′0 and ΔrH′0 can be obtained directly, without performing any transformation, by simply writing the chemical reactions with all the pseudoisomers explicitly included and the elements and charges balanced. The appropriate procedures for computing the stoichiometric coefficients for the pseudoisomers are fully explained by means of an example calculation for the biochemical ATP hydrolysis reaction. It is concluded that the analysis reunifies the “two separate worlds” of conventional thermodynamics and transformed thermodynamics.

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