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The Infra-red Absorption Spectrogram of Ethylidene Fluoride
This thesis is a study of the near infra-red absorption spectrum of ethylidene fluoride.
An Application of the Reformatsky Reaction to the Thiophene Series of Compounds
In view of the increasing importance of thiophene derivatives as chemotherapeutic agents, it was considered of interest to apply the Reformatsky reaction to the synthesis of compounds containing the thiophene nucleus with the thought that these might serve as intermediates for further syntheses.
Acetophenone Derivatives; N-Diphenylmethyl and N-Fluorenyl Piperidines
This thesis is a study of α-(4-aminophenylsulfonyl)-acetophenone derivatives; n-diphenylmethyl and n-fluorenyl piperidines.
The Attempted Synthesis of some Heterocyclic Sulfones
This thesis describes two experiments: one related to antihistamines, and the other related to antitubercular compounds.
A Chemical Analysis of the Peanut
The object of this paper is to make an analysis of the mineral and food content of the peanut and to compare them with a balanced food.
Hydantoins as Anticonvulsants. II. 5-Substituted-Amino Derivatives of 5-Phenylhydantoin
This thesis is a study of 5-substituted-amino derivatives of 5-phenylhydantoin and anticonvulsant activity.
The Hydrolysis of α-(Benzenesulfonyl)-Acetophenone
In view of the unexpected behavior of α-(benzenesulfonyl)-acetophenone toward hydrolysis and because of the possible physiological importance of its derivatives it was deemed of interest to make a further study of the hydrolysis of this compound. It was decided to study both the acid and basic hydrolysis of this compound. The problem consisted of finding a satisfactory means of analyzing the hydrolysis products, and carrying out the hydrolysis under the different conditions.
Hydantoins as Anticonvulsants. III. 5-Alkoxy- and Aryloxymethyl-5-(2-Thienyl) Hydantoins
It has been shown in the case of a compound synthesized in this laboratory that substitution of the thienyl group for one of the phenyl groups in diphenyl hydantoin produces a compound with less toxicity and somewhat greater activity. It was considered of interest to carry out an analogous substitution in the series of 5-phenyl-5-alkoxymethylhydantions.
Hydantoins as Anticonvulsants. IV. The Synthesis of 5-Substituted-5-(2-Tetrahydropyranyl) Hydantoins
The project discussed in the paper consists of the substitution of another type of heterocycle, 2-tetrahydropyranyl, in position 5 of the hydantoin nucleus.
The Syntheses of Amino Substituted Salicylic Acids and Related Compounds
The introduction of the ether linkage into various compounds imparts physiological activity, hence the synthesis of various ether derivatives involving the phenol group seemed to be a possible route to tuberculostatic substances. The compounds reported in this work are to be tested for tuberculostatic properties by Parke, Davis and Company.
The Synthesis of N-(4-Nitrophenacyl)-4-Alkylpyridinium Halides and Reduction Products
The synthesis of several N-(4-nitrophenacyl)-4-alkylpyridinium halides and their reduction products, 1-(4-aminophenyl)-2-[1-(4-alkylpiperidyl)]ethanols, was undertaken because of structural analogies between these and other physiologically active compounds, such as chloroamphenicol (I), 4,4'-diaminodiphenyl sulfone (II), and 2,2-bis(p-aminophenyl)-1,1,1-trichloroethane (III).
The Mercury-Sensitized Photochemical Reactions of Cyclohexane
This study is about the mercury sensitized photochemical reactions of cyclohexane.
Synthesis of a-(p-Aminophenylsulfonyl)-Substitutedacetophenones
This thesis describes a procedure used to synthesize a-(p-Aminophenylsulfonyl)-p-methylacetophenone, a-(p-aminophenylsulfonyl)-p-bromoacetophenone, and a-(p-aminophenylsulfonyl)-p-methoxyacetophenone for study as possible new anti-tubercular agents.
Modeling Transition Metal Chemistry for Catalytic Functionalization of Molecules
The diversity of transition metal complexes allows for a wide range of chemical processes to be mediated by the metal, from catalysis to surface chemistry. Investigations into the structure and electronic configuration of transition metal complexes allow for tuning of desired species by modifications to the ligands and/or metals to achieve more efficient thermodynamics and kinetics for the process of interest. Transition metals, often used in catalysts for a number of important processes, require detailed descriptions of intermediates, transition states and products to fully characterize a reaction mechanism(s) in order to design more active and efficient catalysts. Computational investigations into inorganic catalysts are explored with the aim of understanding the activity of each species and how modifications of supporting ligands, co-ligands and metals vary the interaction along the reaction pathway. Reported results give important insight into the development of the most active complexes in addition to determining the least active complexes to aid experimental development. This report first investigates the mechanisms of two unique transfer reactions: 1) formation of low coordinate nickel-nitrene ((P~P)Ni=NR; P~P = 1,2-bis(dihydrophosphino)-ethane or 1,2-bis(difluoromethylphosphino)-ethane) complexes as catalysts for nitrogen atom transfer and 2) oxidation of a triphosphorus niobium complex, [(η2-P3SnPh3)Nb(OMe)3], for the transfer of the phosphorus synthon, Ph3SnP3. These reactions have utility in the synthesis of nitrogen and phosphorus containing molecules, respectively, and the results presented provide mechanistic insight into the synthesis of the organometallic intermediates. Additionally, a computational approach towards rational catalyst design was performed on the ruthenium based hydroarylation catalyst TpRu(CO)(Ph) [Tp = hydrido-tris(pyrazolyl)borate]. Targeted modifications at the Tp, metal and co-ligand (CO) sites were studied in order to tune the electronics and sterics of the catalyst. Modifications, through computational methods, provided a more cost- and time-efficient way to study the impact of modifications, which provided direct input into attractive synthetic targets. The research …
Chirped-Pulse Fourier Transform Microwave Spectroscopy of Fluoroiodoacetonitrile and Chloropentafluoroacetone
This work focuses on finding the complete iodine and nitrogen nuclear electric quadrupole coupling tensors for fluoroiodoacetonitrile using chirped-pulse Fourier transform microwave spectroscopy. Fluoroiodoacetonitrile contains two hyperfine nuclei, iodine (I=5/2) and nitrogen (I=1) and the spectra were observed with great resolution. A total of 499 transitions were observed for this molecule. The a, b and c rotational constants were obtained. A study of chloropentafluoroacetone was also done using chirped-pulse Fourier transform microwave spectroscopy. The two chlorine isotopes for this molecule, Cl-35 and Cl-37 were observed and 326 and 170 transitions were recorded, respectively.
Design and Development of Soft Landing Ion Mobility: A Novel Instrument for Preparative Material Development
The design and fabrication of a novel soft landing instrument Soft Landing Ion Mobility (SLIM) is described here. Topics covered include history of soft landing, gas phase mobility theory, the design and fabrication of SLIM, as well as applications pertaining to soft landing. Principle applications devised for this instrument involved the gas phase separation and selection of an ionized component from a multicomponent gas phase mixture as combing technique to optimize coatings, catalyst, and a variety of alternative application in the sciences.
Photophysics and Photochemistry of Copper(I) Phosphine and Collidine Complexes: An Experimental/Theoretical Investigation
Copper(I) complexes have been studied through both experimental and computational means in the presented work. Overall, the work focuses on photophysical and photochemical properties of copper(I) complexes. Photophysical and photochemical properties are found to be dependent on the geometries of the copper(I) complexes. One of the geometric properties that are important for both photochemical and photophysical properties is coordination number. Coordination numbers have been observed to be dependent on both ligand size and recrystallization conditions. The complexes geometric structure, as well as the electronic effects of the coordination ligands, is shown both computationally as well as experimentally to affect the emission energies. Two-coordinate complexes are seen to have only weak emission at liquid nitrogen temperature (77 K), while at room temperature (298 K) the two-coordinate complexes are not observed to be luminescent. Three-coordinate complexes are observed to be luminescent at liquid nitrogen temperature as well as at room temperature. The three-coordinate complexes have a Y-shaped ground (S0) state that distorts towards a T-shape upon photoexcitation to the lowest lying phosphorescent state (T1). The geometric distortion is tunable by size of the coordinating ligand. Luminescence is controllable by limiting the amount of non-radiative emission. One manner by which non-radiative emission is controlled is the amount of geometric distortion that occurs as the complex undergoes photoexcitation. Bulky ligands allow for less distortion than smaller ligands, leading to higher emission energies (blue shifted energies) with higher quantum efficiency. Tuning emission and increasing quantum efficiencies can be used to create highly efficient, white emitting materials for use in white OLEDS.
Advancements in Instrumentation for Fourier Transform Microwave Spectroscopy
The efforts of my research have led to the successful construction of several instruments that have helped expand the field of microwave spectroscopy. The classic Balle-Flygare spectrometer has been modified to include two different sets of antenna to operate in the frequency ranges 6-18 GHz and 18-26 GHz, allowing it to function for a large range without having to break vacuum. This modified FTMW instrument houses two low noise amplifiers in the vacuum chamber to allow for the LNAs to be as close to the antenna as physically possible, improving sensitivity. A new innovative Balle-Flygare type spectrometer, the efficient low frequency FTMW, was conceived and built to operate at frequencies as low as 500 MHz through the use of highly curved mirrors. This is new for FTMW techniques that normally operate at 4 GHz or higher with only a few exceptions around 2 GHz. The chirped pulse FTMW spectrometer uses horn antennas to observe spectra that span 2 GHz versus the standard 1 MHz of a cavity technique. This instrument decreases the amount of time to obtain a large spectral region of relative correct intensity molecular transitions. A Nd:YAG laser ablation apparatus was attached to the classic Balle-Flygare and chirped pulse FTMW spectrometers. This allowed the study of heavy metal containing compounds. The instruments I constructed and the techniques I used have allowed the discovery of further insights into molecular chemistry. I have seen the effects of fluorinating an alkyl halide by determining the geometry of the carbon backbone of trans-1-iodoperfluoropropane and observing a ΔJ = 3 forbidden transition caused by a strong quadrupole coupling constant on this heavy molecule. The quadrupole coupling tensors of butyronitrile, a molecule observed in space, have been improved. The nuclear quadrupole coupling tensor of difluoroiodomethane was added to a list of variably fluorinated methyl …
Cu Electrodeposition on Ru-Ta and Corrosion of Plasma Treated Cu in Post Etch Cleaning Solution
In this work, the possibility of Cu electrodeposition on Ru-Ta alloy thin films is explored. Ru and Ta were sputter deposited on Si substrate with different composition verified by RBS. Four point probe, XRD, TEM and AFM were used to study the properties of Ru-Ta thin films such as sheet resistance, crystallinity, grain size, etc. Cyclic voltammetry is used to study the Cu electrodeposition characteristics on Ru-Ta after various surface pretreatments. The results provide insights on the removal of Ta oxide such that it enables better Cu nucleation and adhesion. Bimetallic corrosion of Cu on modified Ru-Ta surface was studied in CMP related chemicals. In Cu interconnect fabrication process, the making of trenches and vias on low-k dielectric films involves the application of fluorocarbon plasma etch gases. Cu microdots deposited on Ru and Ta substrate were treated by fluorocarbon plasma etch gases such as CF4, CF4+O2, CH2F2, C4F8 and SF6 and investigated by using x-ray photoelectron spectroscopy, contact angle measurement and electrochemical techniques. Micropattern corrosion screening technique was used to measure the corrosion rate of plasma treated Cu. XPS results revealed different surface chemistry on Cu after treating with plasma etching. The fluorine/carbon ratio of the etching gases results in different extent of fluorocarbon polymer residues and affects the cleaning efficiency and Cu corrosion trends.
Computational Investigation of Molecular Optoelectronic and Biological Systems
The scope of work in this dissertation has comprised several major investigations on applications and theoretical studies of ab initio quantum mechanics and density functional theory where those techniques were applied to the following: (i) investigation of the performance of density functionals for the computations of molecular properties of 3d transition metal containing systems; (ii) guidance for experimental groups for rational design of macrometallocyclic multinuclear complexes with superior π-acidity and π-basicity that are most suitable for p- and n-type semiconductors of metal-organic molecules and nanomaterials; (iii) investigation of the metallo-aromaticity of multi-nuclear metal complexes; (iv) investigation of the kinetics and thermodynamics of copper-mediated nitrene insertion into C-H and H-H bond; and (v) accurate computations of dissociation energies of hydrogen-bonded DNA duplex moieties utilizing the resolution of identity correlation consistent composite approach (RI-ccCA).
Accuracy and Efficiency in Computational Chemistry: The Correlation Consistent Composite Approach
One of the central concerns of computational chemistry is that of efficiency (i.e. the development of methodologies which will yield increased accuracy of prediction without requiring additional computational resources – RAM, disk space, computing time). Though the equations of quantum mechanics are known, the solutions to these equations often require a great deal of computing power. This dissertation primarily concerns the theme of improved computational efficiency (i.e. the achievement of greater accuracy with reduced computational cost). Improvements in the efficiency of computational chemistry are explored first in terms of the correlation consistent composite approach (ccCA). The ccCA methodology was modified and this enhanced ccCA methodology was tested against the diverse G3/05 set of 454 energetic properties. As computational efficiency improves, molecules of increasing size may be studied and this dissertation explored the issues (differential correlation and size extensivity effects) associated with obtaining chemically accurate (within 1 kcal mol-1) enthalpies of formation for hydrocarbon molecules of escalating size. Two applied projects are also described; these projects concerned the theoretical prediction of a novel rare gas compound, FKrOH, and the mechanism of human glutathione synthetase’s (hGS) negative cooperativity. The final work examined the prospect for the parameterization of the modified embedded atom method (MEAM) potential using first principles calculations of dimer and trimer energies of nickel and carbon systems. This method of parameterization holds promise for increasing the accuracy of simulations for bulk properties within the field of materials science.
Boron Nitride by Atomic Layer Deposition: A Template for Graphene Growth
The growth of single and multilayer BN films on several substrates was investigated. A typical atomic layer deposition (ALD) process was demonstrated on Si(111) substrate with a growth rate of 1.1 Å/cycle which showed good agreement with the literature value and a near stoichiometric B/N ratio. Boron nitride films were also deposited by ALD on Cu poly crystal and Cu(111) single crystal substrates for the first time, and a growth rate of ~1ML/ALD cycle was obtained with a B/N ratio of ~2. The realization of a h-BN/Cu heterojunction was the first step towards a graphene/h-BN/Cu structure which has potential application in gateable interconnects.
The Mercury-Sensitized Photochemical Reactions of Isopropyl Benzene and Methylcyclohexane
This thesis describes the theoretical results of mercury-sensitized photochemical reactions of isopropyl benzene and methylcyclohexane. The reactions are carried out and the results are analyzed.
Barbituric Acids as Anticonvulsants. IV. 5-Substituted-Mercapto Derivatives of 5-Phenylbarbituric Acids.
This study involves compounds of the barbituric acid series are well known for their use as anesthetics and sedatives.
A Study of Substituted Diphenylacetic Acids
This thesis describes the creation of substituted diphenylacetic acids and their results.
A Comparison of the Achievements of Science and Non-Science Majors Enrolled in General Chemistry at North Texas State College
It is the specific purpose of this investigation to determine the difference, if any, in the amount of practical, everyday chemistry learned by the science majors as opposed to the non-science majors enrolled in general chemistry at the North Texas State College during the school year 1950-1951.
Derivatives of Sulfonamide
This thesis describes experiments in creating derivatives of sulfonamide. The derivatives were then submitted for testing for anti-tubercular activity.
Preparation of Pyridinium Derivatives of 2,3-Dichloro-5(8?)-Nitro-1,4-Naphthoquinone
This paper describes the preparation of pyridine derivatives of 2,3-dichloro-5(8?)-nitro-1,4-naphthoquinone. A method for the nitration of 2,3-dichloro-1,4-naphthoquinone is also described. Certain 4-n-alkyl, 3,4-dialkyl, and 4-cycloalkyl pyridine derivatives are caused to undergo condensation reactions with the nitrated naphthoquinone, giving rise to a series of compounds of the preceding type (X). All of the compounds prepared will be tested for anti-tubercular activity by Parke-Davis and Company.
Hydantoins as Anticonvulsants. VI. 5-Substituted-Mercapto Derivatives of 5-Phenylhydantoin
This thesis describes the process of synthesizing 5-substituted-mercapto derivatives of hydantoin in which the sulfur of the side chain is attached directly to the hydantoin nucleus.
A Study of the Reduction Products of N-(4-Nitrophenacyl)-4-(1-Hexyl)pyridinium Bromide
Because of the structural analogies between these compounds and several other physiologically active compounds, such as chloroamphenicol, 4,4'-diaminodiphenyl sulfone, and 2,2-bis-(p-aminophenyl)-1,1,1-trichloroethane, a more complete study of the reduction products and the sequence of catalytic reduction of N-(4-nitrophenacyl)-4-(1-hexyl)pyridinium bromide was made in this investigation.
Stereoisomerism of Dimethyl Muconate
The acid which is analogous to the next member of the diphenylpolyenes, 1,4-diphenylbutadiene, is muconic acid. This acid has been chosen to be investigated in an effort to isolate all the stereoisomers of a set containing more than two isomers.
Nitrogen Derivatives of I-phenylazimidoquinone
A series of analogous reactions employing as a nucleus I-phenylazimidoquinone has been investigated.
Interfacial Electrochemistry of Copper and Spectro-Electrochemical Characterization of Oxygen Reduction Reaction
The first part of this dissertation highlights the contents of the electrochemical characterization of Cu and its electroplating on Ru-based substrates. The growth of Ru native oxide does diminish the efficiency of Cu plating on Ru surface. However, the electrochemical formed irreversible Ru hydrate dioxide (RuOxHy) shows better coverage of Cu UPD. The conductive Ru oxides are directly plateable liner materials as potential diffusion barriers for the IC fabrication. The part II of this dissertation demonstrates the development of a new rapid corrosion screening methodology for effective characterization Cu bimetallic corrosion in CMP and post-CMP environments. The corrosion inhibitors and antioxidants were studied in this dissertation. In part III, a new SEC methodology was developed to study the ORR catalysts. This novel SEC cell can offer cheap, rapid optical screening results, which helps the efficient development of a better ORR catalyst. Also, the SEC method is capable for identifying the poisoning of electrocatalysts. Our data show that the RuOxHy processes several outstanding properties of ORR such as high tolerance of sulfation, high kinetic current limitation and low percentage of hydrogen peroxide.
Molecular Structure Analyses of Asymmetric Hydrocarbon Liquid Compounds in the Gas Phase Using Chirped-pulse Fourier Transform Microwave Spectroscopy: Acyl Chlorides and Perfluorinated Acyl Chlorides
Examinations of the effects of (a.) alkyl carbon chain length and (b.) perfluorination of acyl chlorides; propionyl chloride, butyryl chloride, valeroyl chloride, and perfluorinated acyl chlorides; perfluoropropionyl chloride and perfluorobutyryl chloride, are reported and compared using CP-FTMW spectroscopy. All of these molecules are already published in various journals except for valeroyl chloride. The chapters are organized by molecule alkyl chain length and include some background theory. Conformational stability, internal rotation, helicity, and ionic character of the C-Cl bond via the nuclear electric quadrupole coupling constant (χzz) are analyzed. Results show syn, syn-anti/syn-gauche, and syn-anti-anti/syn-gauche-anti stable conformations. Internal rotation was only seen in propionyl chloride. Helicity was not observed. (χzz) was observed to be inert to alkyl chain length, ~ 60 MHz and ~ 65 MHz for the nonfluorinated and fluorinated acyl chlorides. Partial fluorination and varying functional groups are recommended.
Electrochemical Quartz Crystal Microbalance Study Of Bismuth Underpotential Deposition On Ruthenium And On Electrochemically Formed Ruthenium Oxide
Kinetics and thermodynamics of bismuth (Bi) underpotential deposition (UPD) on ruthenium (Ru) and on electrochemically formed Ru oxide are studied using electrochemical quartz crystal microbalance technique. The Bi UPD and Bi bulk deposition are observed both on Ru and on electrochemically formed Ru oxide electrodes. The anodic peak potential of Bi UPD shifts slightly to positive potential as the scan rate increases. The peak current ratio (IAnode/ICathode) of Bi UPD and Bi bulk increases as the scan rate increases. Bi monolayer coverage calculated from mass (MLMass) and from charge (MLCharge) with scan rates dependent are compared both in Bi UPD region and in Bi bulk region. Stability and oxidation time effects are also investigated. Bi UPD on Ru and on electrochemically formed Ru oxide are quasi-reversible, scan rate independent, oxidation time dependent, and have higher plating efficiency on Ru. However, Bi bulk deposition on Ru and on electrochemically formed Ru oxide are quasi-reversible, scan rate dependent, oxidation time independent, and have higher plating efficiency on electrochemically formed Ru oxide. Both Bi UPD adatoms and Bi bulk are unstable in 0.5M H2SO4.
Sodium Ion Self-Diffusion in Molten Mixtures
This work is an extension of Yin's work studying the diffusion of Na ion in the PbCl2-NaCl system, but at more dilute compositions of NaCl.
A Study of Asymmetric Syntheses in Coordination Chemistry
Since only one example of an asymmetric synthesis which involved an intermediate containing an optically active ligand has been reported, two questions immediately arise: "Is this type of asymmetric synthesis an isolated example, or is it a stepping stone toward a generalized trend for Co (III) which may be extended to include levo rotatory, as well as dextro rotatory molecules?" In addition, asymmetric synthesis affords a new avenue for synthesizing resolved neutral complexes.
Diffusion of Na²² in the Molten PbCl₂-NaCl System
The object of this thesis is to establish the diffusion coefficient of Na ion in PbCl2-NaCl mixtures and to compare its relationship to the other species.
Reductions of 3,6-diphenyl-s-tetrazines
In the course of attempting to prepare 3,6-bis(hydroxy-methyl)-s-tetrazine via the reduction of 3,6-bis(carboxy)-s-tetrazine with lithium aluminum hydride, it became apparent that the tetrazine ring was cleaved.
Preparation of Styrl Derivatives of 2,3-dimethyl-4,9-dioxo-1(2-propyl)-naphth[2,3-d]
A series of compounds were prepared by condensing 2,3-dimethyl-4,9-dioxo-1-(2-propyl)-naphth[2,3-d] imidazolium iodide with various aromatic aldehydes.
An Infrared Study of some Ω-Phenyl and Ω-Benzoyl Alkanoic Acids
There is no available information in the literature on interaction between carboxyl hydrogen and ω-phenyl groups. Consequently, it was of interest to seek such interactions. Some form of interaction is evident from the study of the spectra of some phenylalkanoic acids and benzoyalkanoic acids.
Synthesis and Infrared Spectra of Substituted Phthalimidines
A number of N-substituted-3-hydroxy-3-phenylphthal-imidines and some of the isomeric amides have been prepared in order to study changes in the infrared spectra of these compounds due to structural changes in the molecule, particularly with reference to a hydroxyl band at 3.0µ and a carbonyl band at 5.75µ.
Infrared Studies of Anions of Organic Acids
The present work is a part of a systematic investigation of the frequency shifts in infrared absorption produced by changing to the anions carbonyl containing acidic compounds.
Intermediates for Paracyclophane Synthesis
It is proposed in this thesis that the imperfect systems of Cram and of Schubert be combined with some modifications.
The Exchange of Bismuth Tetra-Iodide and Bismuth Ions in an Ion-Precipitate System
This paper is a study of the exchange of bismuth tetra-iodide and bismuth ions in an ion-precipitate system.
Pyridinium Derivatives of 9,10-Endo-o-Phenylene-9,10-Dihydro-1,4-Anthraquinone
The compounds reported here were prepared for the purpose of determining the effects of active groups on the pyridine ring, and to determine the effects of substituted methyl groups on the nucleus. These compounds are to be tested for tuberculostatic activity.
Photochemistry of Isopropyl Alcohol
This study discusses the effects of the photochemistry of isopropyl alcohol.
Diffusion of Pb210 and Cl36 in the Molten PbCl2-NaCl System
Since 1955 research has been conducted at North Texas State College on diffusion in molten salts. The object of this work was a continuation of the diffusion studies, specifically the diffusion of Pb210 and Cl36 in molten PbCl2-NaCl mixtures.
The Turbidimetric Determination of Lead
The turbidimetric method for the determination of lead ion developed in this work is not intended as a replacement for standard analytical procedures, but is presented solely as a laboratory exercise for courses in elementary instructional analysis.
Infrared Studies of Anions of Barbituric Acids
As long ago as 1881, it was realized that a functional group of atoms in a molecule would cause an absorption band to appear at a particular frequency in the infrared spectrum of the molecule. In more recent years, the concept of characteristic group frequencies has become firmly established and has resulted in the present widespread use of infrared spectroscopy. There appear to have been relatively few studies of infrared absorption of organic acids as compared with their salts.
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