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2002

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Length-At-Age In Juvenile Patagonian Toothfish (Dissostichus Eleginoides), J. Ashford, C. Jones, S. Bobko, I. Everson Jan 2002

Length-At-Age In Juvenile Patagonian Toothfish (Dissostichus Eleginoides), J. Ashford, C. Jones, S. Bobko, I. Everson

OES Faculty Publications

We used the otoliths from a sample of Dissostichus eleginoides pre-recruits, whose length density was distinctly polymodal, to see whether ages estimated by reading otoliths were congruent with the length modes observed. Length densities by age were compared graphically with the overall length density observed. Additionally, ages were predicted for each fish based on length, and compared with ages estimated from reading otoliths in a goodness-of-fit test. The majority of the otoliths (83.6%) were estimated to be from fish 1+ or 2+ years old, with mean total lengths of 32.5 cm and 41.3 cm respectively. No difference was found between …


The Transformation Of Iodate To Iodide In Marine Phytoplankton Cultures, George T. F. Wong, Ajcharaporn U. Piumsomboon, William M. Dunstan Jan 2002

The Transformation Of Iodate To Iodide In Marine Phytoplankton Cultures, George T. F. Wong, Ajcharaporn U. Piumsomboon, William M. Dunstan

OES Faculty Publications

Six species of phytoplankton, representing 6 major phylogenetic groups (2 oceanic species: a cyanobacteria, Synechococcus sp., and a coccolithophorid, Emiliania huxleyi; and 4 coastal species: a prasinophyte, Tetraselmis sp., the green algae Dunaliella tertiolecta, the diatom Skeletonema costatum and a dinoflagellate Amphidinium carterae) were tested for their ability to reduce iodate to iodide in batch cultures. They all did so to varying degrees. Thus, the reduction of iodate to iodide by phytoplankton may be a general phenomenon in the marine environment. At ambient concentrations of iodate, the rates of depletion of iodate and appearance of …


Synthesis Of Novel Acidic Mono Azo Dyes And An Investigation Of Their Use In The Textile Industry, Emel Yildiz, Hami̇t Boztepe Jan 2002

Synthesis Of Novel Acidic Mono Azo Dyes And An Investigation Of Their Use In The Textile Industry, Emel Yildiz, Hami̇t Boztepe

Turkish Journal of Chemistry

1,2-hydroxo phenyl azo,8-amino naphthalene, 3,6-disulfonic acid Mono sodium salt (HFANS) and its metal complex with chromium (III) salt (ligand metal ratio 1:1) were synthesized as H-acid derivatives. Having an acidic character these dyes are used for dyeing polyamide and protein fibers. Their properties such as dyeing, wash fastness and color classification were investigated according to international standard methods.


The Selective Protection And Deprotection Of Ambident Nucleophiles With Parent And Substituted Triarylmethyls, İbrahi̇m Demi̇rtaş, Bülent Büyükkidan, Mahfuz Elmastaş Jan 2002

The Selective Protection And Deprotection Of Ambident Nucleophiles With Parent And Substituted Triarylmethyls, İbrahi̇m Demi̇rtaş, Bülent Büyükkidan, Mahfuz Elmastaş

Turkish Journal of Chemistry

N-triphenylmethyl and N-4,4'-dimethoxytriphenylmethyl of o-aminophenol, m-aminophenol, and p-aminophenol compounds were easily prepared from triphenylmethyl chloride and 4,4'-dimethoxytriphenyl- methyl chloride. S-triphenylmethyl-2-mercapto ethanol was also selectively synthesized using the triphenylmethyl chloride and 2-mercapto ethanol. The reactivity of nitrogen and sulfur versus oxygen in the protection reactions was compared. In principle, the protection of aminophenols and 2-mercapto ethanol with triarylmethyls (trityls) may take place on the oxygen. However, in this framework, we discuss the different reactivities of oxygen, nitrogen and sulfur towards triphenylmethyl chloride (TrCl) and 4,4'-dimethoxytriphenylmethyl chloride (DMTrCl) and find that nitrogen and sulfur are more reactive than oxygen.


Terpenoids And Aromatic Compounds From Euphorbia Heteradena, Sevi̇l Öksüz, Ayhan Ulubelen, Asli Barla, Wolfgang Voelter Jan 2002

Terpenoids And Aromatic Compounds From Euphorbia Heteradena, Sevi̇l Öksüz, Ayhan Ulubelen, Asli Barla, Wolfgang Voelter

Turkish Journal of Chemistry

Euphorbia heteradena Jaub. & Spach (Euphorbiaceae), a plant endemic to Turkey, has not been investigated previously. The CH_{2}Cl_{2} extract of the aerial parts of Euphorbia heteradena yielded 24-methylenecycloartanol, cycloart-25-en-3\beta ,24-diol, cycloart-22-en-3\beta ,25-diol, vomifoliol, vomifoliol 9-O-\beta -D-glucopyranoside, 3,4,3'-tri-O-methoxy ellagic acid, syringic acid and scopoletin. The structures of the isolates were identified by high field spectroscopic methods including 1D and 2D NMR techniques.


Hplc Method For The Analysis Of Paracetamol, Caffeine And Dipyrone, M. Levent Altun Jan 2002

Hplc Method For The Analysis Of Paracetamol, Caffeine And Dipyrone, M. Levent Altun

Turkish Journal of Chemistry

An accurate, simple, reproducible and sensitive method for the determination of paracetamol, caffeine and dipyrone was developed and validated. Paracetamol, caffeine and dipyrone were separated using a \mu -Bondapack C _{8} column by isocratic elution with a flow rate of 1.0 ml/min. The mobile phase composition was 0.01 M KH_2PO_{4-} -methanol-acetonitrile-isopropyl alcohol (420: 20: 30: 30) (v/v/v/v) and spectrophotometric detection was carried out at 215 nm. The linear range of determination for paracetamol, caffeine and dipyrone were 0.409-400 \mu g/ml, 0.151-200 \mu g/ml and 0.233-600 \mu g/ml, respectively. The method was shown to be linear, reproducible, specific, sensitive and rugged.


Trypsin-Catalyzed Peptide Synthesis In Acetonitrile With Low Water Content, Yeşi̇m Yeşi̇loğlu, Ayten Sağiroğlu Jan 2002

Trypsin-Catalyzed Peptide Synthesis In Acetonitrile With Low Water Content, Yeşi̇m Yeşi̇loğlu, Ayten Sağiroğlu

Turkish Journal of Chemistry

Trypsin was immobilized to alumina by adsorption from its aqueous solutions. The activity of trypsin was increased by immobilization for peptide synthesis. With these immobilized enzymes Bz-Arg-Leu-NH_{2} dipeptide synthesis was carried out. Iso amylalcohol, tetrahydrofuran and acetonitrile were used as solvents giving the highest yield in the peptide formation reaction. The yield of the peptide was strongly dependent on water content in the reaction medium. The stability of alumina-immobilized trypsin is described.


Titrimetric And Spectrophotometric Determinations Of Some Phenothiazine Psychotropics Using Chloramine-T, Kanakapura Basavaiah, Javarappa Manjunathaswamy Jan 2002

Titrimetric And Spectrophotometric Determinations Of Some Phenothiazine Psychotropics Using Chloramine-T, Kanakapura Basavaiah, Javarappa Manjunathaswamy

Turkish Journal of Chemistry

A simple, convenient and accurate indirect titrimetric method and a rapid, sensitive and precise indirect spectrophotometric method for the determination of six phenothiazine drugs using chloramine-T as an oxidant are described. The titrimetric method is based on the oxidation of the drugs in sulphuric acid medium by a known excess of chloramine-T and iodometric determination of the unreacted chloramine-T. In the spectrophotometric method, the unreacted oxidant is made to react with metol in the presence of an aromatic amine to produce a purple-red product with the absorption maximum at 520 nm. The absorbance is found to decrease linearly with increasing …


Cover And Contents Jan 2002

Cover And Contents

Turkish Journal of Chemistry

No abstract provided.


Synthesis And Protection Of Some Amidines, Kadi̇r Dabak Jan 2002

Synthesis And Protection Of Some Amidines, Kadi̇r Dabak

Turkish Journal of Chemistry

A series of benzamidine derivatives were synthesized from substituted benzonitrile compounds and protected with the tert-butoxycarbonyl group.


Electrochemical Investigation Of 4'-Haloderivatives Of N,N-Dimethyl-4-Aminoazobenzene, Mustafa Uçar, Ali̇ Osman Solak, M. Levent Aksu, Mehmet Toy Jan 2002

Electrochemical Investigation Of 4'-Haloderivatives Of N,N-Dimethyl-4-Aminoazobenzene, Mustafa Uçar, Ali̇ Osman Solak, M. Levent Aksu, Mehmet Toy

Turkish Journal of Chemistry

In this study, the electrochemical behaviour of 4' -halogene-N,N-dimethyl-4-aminoazobenzene derivatives were investigated using various polarographic and voltammetric methods. The peak potentials of these derivatives were observed to shift towards negative values with increase in pH. The standard rate constants were determined with (Laviron technique) or without (Nicholson and Klingler-Kochi techniques) taking the adsorption phenomena into account. The diffusion coefficients were calculated from the cyclic voltammetric data using the method developed by Garrido. The amount of adsorbed substances (surface excess values) and transfer coefficients for the electron transfer were also determined. These compounds can be quantitatively determined between 1 x 10^{-5} …


Thermal Behaviour Of Copper(Ii), Nickel(Ii), Cobalt(Ii) And Palladium(Ii) Complexes Of N,N-Dimethyl-N'-Benzoylthiourea, Göktürk Avşar, Nevzat Külcü, Hakan Arslan Jan 2002

Thermal Behaviour Of Copper(Ii), Nickel(Ii), Cobalt(Ii) And Palladium(Ii) Complexes Of N,N-Dimethyl-N'-Benzoylthiourea, Göktürk Avşar, Nevzat Külcü, Hakan Arslan

Turkish Journal of Chemistry

N,N-dimethyl-N'-benzoylthiourea (DMBT) complexes of Ni(II), Cu(II), Co(II) and Pd(II) were synthesised. The thermal decomposition of these metal complexes was investigated by TG, DTG and DTA. A GC-MS combined system was used to identify the products during pyrolytic decomposition. The pyrolytic end-products were identified by X-ray powder diffraction. The thermoanalytical data of these complexes are presented in this communication. The kinetic analysis of the thermogravimetric data was performed by using the Coats-Redfern and Horowitz-Metzger methods. All the metal complexes except Cu(II) complex undergo decomposition in three stages and NiS, CoS, Pd, and Cu remained as end-products of the complexes.


Phenolic Compounds From Scutellaria Pontica, Tayfun Ersöz, Ü. Şebnem Harput, İclal Saracoğlu, İhsan Çaliş, Yukio Ogihara Jan 2002

Phenolic Compounds From Scutellaria Pontica, Tayfun Ersöz, Ü. Şebnem Harput, İclal Saracoğlu, İhsan Çaliş, Yukio Ogihara

Turkish Journal of Chemistry

From the aerial parts of Scutellaria pontica, a phenolic glucoside, 3,5-dihydroxyphenyl \beta -D-glucopyranoside (1); as well as a C-glucosyl flavon, isovitexin (2); flavones and flavone glycosides, 5-hydroxy-7,3',4'-trimethoxyflavone (3); apigenin (4); apigenin-7-O-\beta-D-glucopyranoside (5); and apigenin-7-O-\beta-D-glucopyranoside-4'-O-methylether (6) were isolated in addition to two phenylethanoid glycosides, martynoside (7) and verbascoside (= acteoside) (8). The structures of the isolated compounds were established on the basis of spectroscopic evidence.


Determination Of Linear Alkylbenzene Sulphonates And Their Biodegradation Intermediates By Isocratic Rp-Hplc, Mehmet Akyüz, David J. Roberts Jan 2002

Determination Of Linear Alkylbenzene Sulphonates And Their Biodegradation Intermediates By Isocratic Rp-Hplc, Mehmet Akyüz, David J. Roberts

Turkish Journal of Chemistry

An HPLC method was developed to determine linear alkylbenzene sulphonates (LASs) and their biotransformation products sulphophenyl carboxylates by isocratic chromatography using two C_{18} columns in series. Solid-phase extraction with a (C_{18}) cartridge was employed to isolate LAS from sediment and sewage effluent samples. Sodium perchlorate and ammonium perchlorate were used as ion pair agents. The recovery of the compounds was 94% \pm 2 and 98% \pm 2 respectively for sediment and sewage effluent. It was demonstrated that it is possible to separate LAS compounds and their isomers and homologues using this system.


Molecular Dynamics Simulation Of Phase Transitions In Binary Lj Clusters, Adem Teki̇n, Mi̇ne Yurtsever Jan 2002

Molecular Dynamics Simulation Of Phase Transitions In Binary Lj Clusters, Adem Teki̇n, Mi̇ne Yurtsever

Turkish Journal of Chemistry

The structures of small clusters are studied extensively by classical simulation methods because of their interesting thermodynamic behavior. In this work, we study the thermodynamic properties of binary mixtures of noble gas atoms. Interatomic interactions are defined by 6-12 Lennard-Jones (LJ) potential. Starting from the global minimum of the potential energy surfaces, the systems are heated by increasing the total energy until melting occurs. The melting is observed by monitoring the Lindemann factor. The effects of the relative sizes of A and B atoms and the interaction strength of A-A, A-B, and B-B on the melting temperature of clusters containing …


Base Hydrolysis Kinetics Of Cobalt(Iii) Spiro-Octaamine Dimer, Yakup Baran, Geoffrey Lawrence Jan 2002

Base Hydrolysis Kinetics Of Cobalt(Iii) Spiro-Octaamine Dimer, Yakup Baran, Geoffrey Lawrence

Turkish Journal of Chemistry

The preparation and characterisation of a cobalt (III) complex of octaaza ligand, 5, 5'-bis(4-amino-2-azabutyl)-1,9-diamino-3,7-diazanonane (octaam) is described. The base hydrolysis kinetics of bis cobalt(III) of octaam has been studied spectrophotometrically by the stopped-flow technique. A consequent reaction is observed in the base hydrolysis of the spiro-octaamine with the fast reaction having k_{OH} = 3.55 M^{-1}s^{-1} and the slower reaction k_{OH} = 0.72 M^{-1}s^-1} at 298 K with \Delta H^{\#} = 89 kJ/mol for the fast stage and \Delta H^{\#} = 102 kJ/mol for the slow stage (I = 0.4 M NaClO_4). The fast reaction is assigned to the hydrolysis of …


The Use Of Chloranilic Acid For The Spectrophotometric Determination Of Three Antihistamines, Kanakapura Basavaiah, V. S. Charan Jan 2002

The Use Of Chloranilic Acid For The Spectrophotometric Determination Of Three Antihistamines, Kanakapura Basavaiah, V. S. Charan

Turkish Journal of Chemistry

Cyproheptadine hydrochloride (CPH), methdilazine hydrochloride (MDH) and promethazine theoclate (PMT) were determined in their pure state and in pharmaceutical formulations by a simple spectrophotometric method. The determination was based on the formation of a charge-transfer complex between chloranilic acid as a \pi-acceptor and the studied drugs as n-donors in an acetonitrile-chloroform mixture. The spectra, various experimental parameters, the stoichiometry and the stability of the complexes formed were investigated. The complexes formed were found to absorb at 520 nm. Beer's law is obeyed in the concentration ranges 25-125, 20-100 and 25-150 \mu g ml^{-1}, for CPH, MDH and PMT respectively. The …


Determination Of Calcium, Magnesium And Aluminium In Magmatic Rocks After Ultrasonic Leaching By Flame Aas, M. Hi̇kmet Özkan, Mehmet Akçay Jan 2002

Determination Of Calcium, Magnesium And Aluminium In Magmatic Rocks After Ultrasonic Leaching By Flame Aas, M. Hi̇kmet Özkan, Mehmet Akçay

Turkish Journal of Chemistry

A method of ultrasonic leaching has been developed for the destructive analysis of magmatic rock samples^1. This method was applied to determine three new elements, Ca, Mg and Al, in magmatic rock samples. The accuracy of the ultrasonic leaching method (C_{ULM}) was tested using standard reference materials (SRMs) and the recovery ratio as K_1 = C_{ULM}/C_{SRM} was defined. Another recovery ratio, K_2, was also defined from the results of the conventional dissolution method (CDM), that is K_2 = C_{ULM}/C_{CDM}. The accuracy and precision of the method are comparable with those of conventional methods. The following recovery ratios were obtained for …


Anatomy Of A Coupling Query In A Web Warehouse, Sourav S. Bhowmick, Sanjay Kumar Madria, Wee-Keong Ng, Ee Peng Lim Jan 2002

Anatomy Of A Coupling Query In A Web Warehouse, Sourav S. Bhowmick, Sanjay Kumar Madria, Wee-Keong Ng, Ee Peng Lim

Research Collection School Of Computing and Information Systems

To populate a data warehouse specifically designed for Web data, i.e. web warehouse, it is imperative to harness relevant documents from the Web. In this paper, we describe a query mechanism called coupling query to glean relevant Web data in the context of our web warehousing system called Warehouse Of Web Data (WHOWEDA). Coupling query may be used for querying both HTML and XML documents. Some of the important features of our query mechanism are ability to query metadata, content, internal and external (hyperlink) structure of Web documents based on partial knowledge, ability to express constraints on tag attributes and …


School Choice: Perceptions Of Magnet Schools And Charter School Principals And Parents In Georgia, Mark Lee Boyd Jan 2002

School Choice: Perceptions Of Magnet Schools And Charter School Principals And Parents In Georgia, Mark Lee Boyd

College of Graduate Studies: Theses & Dissertations (1964–2006)

The purpose of this study was to examine perceptions of parents and administrators in selected magnet schools and charter schools in Georgia. The intent was to give administrators of schools in Georgia an understanding of which parents in Georgia are most apt to make a school choice. Additionally, the study was aimed at providing administrators with an understanding of the factors parents considered when selecting a school for their children and what sources of information the parents utilized to find information necessary to make a choice.

To collect data, a survey was distributed to parents and administrators in six magnet …


The Motivational Stories Of How Women Become Scientists: A Hermeneutic Phenomenological Inquiry, Sandra White Watson Jan 2002

The Motivational Stories Of How Women Become Scientists: A Hermeneutic Phenomenological Inquiry, Sandra White Watson

College of Graduate Studies: Theses & Dissertations (1964–2006)

The under-representation of women in science careers is well documented (Astin, Green, Kom, & Riggs, 1991; Felder, Felder, Mauny, Hamrin, & Dietz, 1995; Green, 1989; National Science Foundation, 1996, 1998; Seymour & Hewitt, 1997; Strenta, Elliot, Adair, Scott, & Matier, 1994; Tobias, 1990, 1992). While important information has been published concerning various factors that influenced women to pursue science careers (American Association of University Women, 1992; Debacker & Nelson, 2000; Samuels, 1999), very few research projects have allowed women scientists to share their personal experiences ofwhat motivated them to become scientists in their own voices.

The purpose of this inquiry …


Superintendents' Perceptions Regarding The Impact Of Class Size Reduction On School Facility Planning In Georgia, Andrea Jones Williams Jan 2002

Superintendents' Perceptions Regarding The Impact Of Class Size Reduction On School Facility Planning In Georgia, Andrea Jones Williams

College of Graduate Studies: Theses & Dissertations (1964–2006)

During the 2000 legislative session, Georgia lawmakers felt there was a need to improve education in Georgia. The A-Plus Education Reform Act of 2000 was passed in response to their concerns. One section of this act mandated that public schools reduce class sizes. This mandated reduction in class size has had different impacts on Georgia school systems. Successful implementation has been a daunting task for some school systems. School systems have reported different experiences and challenges during the initial phases of implementation. Problem areas have ranged from a lack of classroom space to teacher availability. These problems hav e been …


Faculty Handbook, Georgia Southern University Jan 2002

Faculty Handbook, Georgia Southern University

Faculty Handbooks

Faculty Handbook for Georgia Southern University for the 2002-2003 academic year. The Faculty Handbook is published online by the Office of the Vice President for Academic Affairs and archived in Digital Commons@Georgia Southern.


2002 Aasu Men's Basketball Guide, Armstrong State University Jan 2002

2002 Aasu Men's Basketball Guide, Armstrong State University

Armstrong Athletics: Men's Basketball Records (Archived)

No abstract provided.


2002 Aasu Tennis Guide, Armstrong State University Jan 2002

2002 Aasu Tennis Guide, Armstrong State University

Armstrong Athletics: Men's Tennis Records (Archived)

No abstract provided.


2002 Aasu Women's Basketball Guide, Armstrong State University Jan 2002

2002 Aasu Women's Basketball Guide, Armstrong State University

Armstrong Athletics: Women's Basketball Records (Archived)

No abstract provided.


2002 Aasu Softball Guide, Armstrong State University Jan 2002

2002 Aasu Softball Guide, Armstrong State University

Armstrong Athletics: Women's Softball Records (Archived)

No abstract provided.


An Empirical Analysis Of Takeover Predictions In The Uk: Application Of Artificial Neural Networks And Logistic Regression, Asim Yuzbasioglu Jan 2002

An Empirical Analysis Of Takeover Predictions In The Uk: Application Of Artificial Neural Networks And Logistic Regression, Asim Yuzbasioglu

Plymouth Business School Theses

This study undertakes an empirical analysis of takeover predictions in the UK. The objectives of this research are twofold. First, whether it is possible to predict or identity takeover targets before they receive any takeover bid. Second, to test whether it is possible to improve prediction outcome by extending firm specific characteristics such as corporate governance variables as well as employing a different technique that has started becoming an established analytical tool by its extensive application in corporate finance field. In order to test the first objective, Logistic Regression (LR) and Artificial Neural Networks (ANNs) have been applied as modelling …


They Did Not Teach: Veterans' Experiences In A Mid-Career Transition Program At An Urban University, Joseph Franklyn Shipes Jan 2002

They Did Not Teach: Veterans' Experiences In A Mid-Career Transition Program At An Urban University, Joseph Franklyn Shipes

Theses and Dissertations in Urban Services - Urban Education

This descriptive phenomenology examines the lived experiences of veterans who attempted a mid-career transition into teaching. The study identifies and describes experiences that led to the outcome decisions of 22 men who enrolled in a Military Career Transition Program (MCTP), completed a Master's Degree in Education, but did not become public school teachers. Self-descriptions of their experience were collected in multiple, open-ended interviews and analyzed using Moustakas's (1994) protocols.

Participants described a transition in four stages (a) preliminary conditions for change, (b) socialization and adjustment, (c) refocusing career goals, and (d) reflective assessment. Planning for career change began with ideal …


Performance Modeling And Prediction For The Scalable Solution Of Partial Differential Equations On Unstructured Grids, Dinesh Kumar Kaushik Jan 2002

Performance Modeling And Prediction For The Scalable Solution Of Partial Differential Equations On Unstructured Grids, Dinesh Kumar Kaushik

Computer Science Theses & Dissertations

This dissertation studies the sources of poor performance in scientific computing codes based on partial differential equations (PDEs), which typically perform at a computational rate well below other scientific simulations (e.g., those with dense linear algebra or N-body kernels) on modern architectures with deep memory hierarchies. We identify that the primary factors responsible for this relatively poor performance are: insufficient available memory bandwidth, low ratio of work to data size (good algorithmic efficiency), and nonscaling cost of synchronization and gather/scatter operations (for a fixed problem size scaling). This dissertation also illustrates how to reuse the legacy scientific and engineering software …