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Investigation Of The Surface Acidity Of A Bentonite Modified By Acid Activation And Thermal Treatment, Tülay Alemdaroğlu, Gülcan Akkuş, Müşerref Onal, Yüksel Sarikaya

Turkish Journal of Chemistry

The adsorption of n-butylamine from its solution in cyclohexane on acid-activated and thermally treated Kütahya/Turkey bentonite (KB) samples was followed using a UV-VIS spectrophotometric method. The experimental data were evaluated by the Langmuir adsorption equation and the total number of surface acid centers (n_{m/mol} g^{-1}) was determined. The variation in n_m values as a function of the mass percent of H_2SO_4 used in activation (10%-70%) and its correlation with variations in surface area (A) and pore volume (V) as a function of the mass percent of H_2SO_4 were investigated for acid- activated KB samples. The variation in n_m values as …

Isolation And Characterization Of A Smectite As A Micro-Mesoporous Material From A Bentonite, Müşerref Önal, Yüksel Sarikaya, Tülay Alemdaroğlu, İhsan Bozdoğan

Turkish Journal of Chemistry

A procedure was assessed for obtaining an optimum amount of a micro-mesoporous material known as smectite from Reşadiye (Tokat/Turkey) bentonite. The procedure, which will permit a better economic evaluation of the Reşadiye reserves, is based on successive settlements of bentonite suspensions during various time intervals. To characterize the original bentonite, its fractions and the high purity smectite product, X-ray diffraction, differential thermal analysis, thermogravimetric analysis, scanning electron microscopy and nitrogen adsorption-desorption techniques were used. The original bentonite contained 50% by mass sodium-rich smectite (NaS) and 10% by mass NaCa-smectite (NaCaS). It also contained illite, clinoptilolite, analcime, feldspar, calcite, dolomite, quartz …

Phenolic, Megastigmane, Nucleotide, Acetophenon And Monoterpene Glycosides From Phlomis Samia And P. Carica, Funda Nuray Yalçin, Tayfun Ersöz, Pinar Akbay, İhsan Çaliş, Ali̇ Arslan Dönmez, Otto Sticher

Turkish Journal of Chemistry

Phytochemical investigations on the aerial parts of Phlomis samia resulted in the isolation of a simple phenolic glucoside, 2,6-dimethoxy-4-hydroxyphenol-1-O-\beta -D-glucopyranoside (1); a megastigmane glucoside, phlomuroside (=3-hydroxy-5,6-epoxy-\beta -ionol-9-O-\beta -D-glucopyranoside) (2); and a nucleotide glycoside, uridine (3). From the aerial parts of P. carica, the same phenolic glucoside, 2,6-dimethoxy-4-hydroxyphenol-1-O-\beta -D-glucopyranoside (1); as well as an acetophenon glucoside, picein (4); and 2 monoterpenoid glucosides, - betulalbuside A (5) and 1-hydroxylinaloyl-6-O-\beta -D-glucopyranoside (6) - were isolated and identified. The structure elucidation of the isolates was based on spectroscopic evidence.

Application Of Ibx Method For The Synthesis Of Ketones From Carboxylic Acids, H. R. Ferhat Karabulut, Mesut Kaçan, Hasan Özyildirim

Turkish Journal of Chemistry

Methoxy phenyl propionic acid and some derivatives are converted to ketones using a new method. All classical methods to obtain ketones from carboxylic acids via acid halide consistently gave very low yields and regularly generated intermolecular cyclisation products or polymeric materials. However, high ketones yields are obtained by using the new IBX method.

Application Of Potassium Chromate-Diphenylcarbazide In The Quantitative Determination Of Ascorbic Acid By Spectrophotometry, Meissam Noroozifar, M. Khorasani Motlagh

Turkish Journal of Chemistry

A spectrophotometric procedure for the determination of ascorbic acid in pure form and in a number of pharmaceutical preparations and real samples has been developed that offers the advantages of simplicity, accuracy, precision and sensitivity over many other methods. The method is based on the oxidation of ascorbic acid by a known excess amount of potassium chromate followed by the estimation of the unreacted amount of chromate by reactions with sym-diphenylcarbazide. The reacted oxidant corresponds to the ascorbic content. At the maximum absorption of 548 nm, Beer's law is obeyed up to 5 \mu g/mL of ascorbic acid. Statistical treatment …

Synthesis And Analgesic And Anti-Inflammatory Activity Of New Pyridazinones, Deni̇z S. Doğruer, M. Fethi̇ Şahi̇n, Esra Küpeli̇, Erdem Yeşi̇lada

Turkish Journal of Chemistry

A new series of 2-(6-oxo-3,5-diphenyl-6H-pyridazin-1-yl)- acetamides and 3-[6-oxo-3,5-diphenyl-6H-pyridazin-1-yl)-propanamides were synthesized and evaluated in terms of their analgesic and anti-inflammatory activities. All compounds except for 7g were more potent than aspirin in a p-benzoquinone--induced writhing test at 100 mg/kg dose. Compounds 7b, 7c and 7e had the highest anti-inflammatory activity; compound 7e was the most potent in terms of analgesic and anti-inflammatory activities and had no ulcerogenic side effects.

Chemical Constituents Of Campanula Lactiflora, Nuretti̇n Yayli, Nuri̇ Yildirim, Asu Usta, Serpi̇l Özkurt, Vi̇ldan Akgün

Turkish Journal of Chemistry

A new flavonoid glycoside, 4'-O-(p-hydroxybenzoyl)-isorhamnetin-3,7- di-O-\beta-D-glucopyranoside (1), and 4 known compounds, sitosterol \beta-D-glucoside (2), bis(2-ethylhexyl) adipate (3), p-hydroxybenzoic acid (4) and ethyl docosanoate (5), were isolated for the first time from Campanula lactiflora and their structures were deduced by high field 1D and 2D NMR and (+) FAB and EI mass spectra.

Synthesis And Evaluation Of Antimicrobial Activity Of New 3-Hydroxy-6-Methyl-4-Oxo-4h-Pyran-2- Carboxamide Derivatives, Mutlu Di̇lsi̇z Aytemi̇r, Di̇lek Demi̇r Erol, Robert Charles Hider, Meral Özalp

Turkish Journal of Chemistry

The synthesis of a range of 3-hydroxy-4-oxo-4H-pyran-2- carboxamide with antimicrobial activity is described. Amide derivatives of pyranone were synthesised using TBTU [2-(1H-benzotriazol-1-yl)-1,1,3,3-tetramethyluronium tetrafluoroborate] as a coupling agent and NMM (N-methylmorpholine) as a base. Antimicrobial activities were determined as MIC values using the microdilution broth method against Staphylococcus aureus, Entrococcus faecalis, Escherichia coli and Pseudomonas aeruginosa for bacteria and Candida albicans, C. krusei and C. parapsilosis for fungi. 3-Hydroxy-6-methyl-4-oxo-4H-pyran-2-[N-(4'-methylcoumarin-7-yl) carboxamide] (8c) exhibited higher antibacterial activity against S. aureus, E. faecalis and E. coli than the other compounds. In addition, 8c was more active against C. krusei than the other synthesised compounds.

6-O-\Alpha-L-Rhamnopyranosylcatalpol Derivative Iridoids From Verbascum Cilicicum, İ. İrem Tatli, Zeli̇ha Ş. Akdemi̇r, Erdal Bedi̇r, Ikhlas A. Khan

Turkish Journal of Chemistry

From the aerial parts of Verbascum cilicicum Boiss., 6 iridoid glycosides, namely catalpol (1), verbaspinoside [= 6-O-(2'' -O-trans-cinnamoyl)-\alpha-L-rhamnopyranosylcatalpol] (2), 6-O-(3''-O-trans-cinna\-moyl)-\alpha-L-rhamnopyranosylcatalpol (3), 6-O-(4''-O-trans-cinnamoyl)-\alpha -L-rhamnopyranosylcatalpol (4), saccatoside [= 6-O-(2''-O-trans-p-coumaroyl)-\alpha-L-rhamnopyranosylcatalpol] (5), and 6-O-(3''-O-trans-p-coumaroyl)-\alpha-L-rhamnopyranosylcatalpol (6), were isolated. The structures of the compounds were elucidated by means of 1 and 2 dimensional (DQF-COSY, HMQC and HMBC) NMR techniques and LC-ESIMS.

Plasticiser Effect On Water Vapour Permeability Properties Of Locust Bean Gum--Based Edible Films, Özgür Altan Bozdemi̇r, Mehmet Tutaş

Turkish Journal of Chemistry

The barrier properties of edible films prepared from polysaccharide polymer (locust bean gum) and various plasticisers (glycerol, propylene glycol, sorbitol, and polyethylene glycol 200) together with hydrophobic modifiers (stearopten and beeswax) were examined. It was determined that the films containing polyethylene glycol 200 (PEG 200) and sorbitol have the lowest water vapour permeability values and the films containing glycerol have the highest WVP values. It was found that the most reasonable of the studied plasticisers was PEG 200. Polysaccharide--based edible films have higher WVP values than those of lipid-- and protein--based edible films. In order to reduce the WVP of …

Cover And Contents

Turkish Journal of Chemistry

No abstract provided.

Crafting A Research Paper, Ronan Fitzpatrick, Kevin O'Donnell

Conference papers

Writing research papers presents numerous different challenges, which vary from how to layout the various pages and format the text to what to include in the different sections that make up the paper. In order to clarify these issues this paper sets out guidelines and best practice approaches and demonstrates their use in the style of this paper.

Anisotropy And Its Relation To Liquefaction Resistance Of Granular Material, Isao Ishibashi, Omer F. Capar

Civil & Environmental Engineering Faculty Publications

This research establishes quantitative relationships between soil's anisotropy and liquefaction resistance for granular materials. Uniform medium density (D_r = 50%) sand specimens were prepared using three different sample preparation techniques (air pluviated (AP), moist tamped (NIT), and moist vibrated (MV)) to create different initial soil fabrics. Undrained cyclic triaxial tests were then performed to determine the liquefaction resistance of each soil specimen. On the same specimens in the triaxial cell, vertical and horizontal compression wave velocities and vertical shear wave velocity (V_s) were measured using piezoelectric bender elements. Anisotropic (transversely isotropic) elastic constants of the soil specimens were …

Agent Chameleons: Agent Minds And Bodies, Brian Duffy, Gregory O'Hare, Alan Martin, John Bradley, Bianca Schoen-Phelan

Conference papers

Agent design has to date concerned itself with the issues pertaining to a single body embedded in a single environment, whether virtual or real. This paper discusses the notion of an agent capable of migrating between information spaces (physical worlds, virtual reality, and digital information spaces). An architecture is presented that facilitates agent migration and mutation within such environments. This will in turn support agent

evolution the ultimate in agent adaptivity

Filter Selection For Spectral Estimation Using A Trichrmatic Camera, David C. Day

Theses

Current imaging practices are based on exploiting metamerism to record and reproduce images. As a result, the data obtained in these images are dependent on the viewing conditions and the observer. While these methods produce acceptable results for day to day use, they often do not exhibit the type of accuracy and control required for scientific purposes such as art conservation. As a solution, many research institutions are now advocating the use of multispectral imaging to record the objects fundamental spectral properties to remove the data's dependency on the observer and viewing environment. The research described in this thesis involved …

New Evidence For Enhanced Ocean Primary Production Triggered By Tropical Cyclone, I. Lin, W. Timothy Liu, Chun-Chieh Wu, George T. F. Wong, Chuanmin Hu, Zhiqiang Chen, Wen-Der Liang, Yih Yang, Kon-Kee Liu

OES Faculty Publications

[1] New evidence based on recent satellite data is presented to provide a rare opportunity in quantifying the long-speculated contribution of tropical cyclones to enhance ocean primary production. In July 2000, moderate cyclone Kai-Tak passed over the South China Sea (SCS). During its short 3-day stay, Kai-Tak triggered an average 30-fold increase in surface chlorophyll-a concentration. The estimated carbon fixation resulting from this event alone is 0.8 Mt, or 2-4% of SCS's annual new production. Given an average of 14 cyclones passing over the SCS annually, we suggest the long-neglected contribution of tropical cyclones to SCS's annual new production may …

Sources Of Sediment Found In Sea Ice From The Western Arctic Ocean, New Insights Into Processes Of Entrainment And Drift Patterns, Dennis A. Darby

OES Faculty Publications

The geochemical fingerprint of entrained Fe oxide mineral grains in Arctic Ocean sea ice is used to determine precise sources of this sediment. This approach substantiates the importance of the Laptev Sea as a source of sea ice and even the presence of Russian ice in the Beaufort Sea off Alaska. Fe oxide grains from the Laptev Sea were found in floes in the Beaufort Sea, Chukchi Borderland, and central Arctic Ocean, demonstrating the importance of sea ice in distributing itself throughout the Arctic Ocean and the potential of transporting sediment from Russian rivers to North American shelves. Banks Island …

Extracellular Enzyme Activity And Uptake Of Carbon And Nitrogen Along An Estuarine Salinity And Nutrient Gradient, Margaret R. Mulholland, Cindy Lee, Patricia M. Gilbert

OES Faculty Publications

Amino acid oxidation (AAO) and peptide hydrolysis (PH) are processes affecting the recycling of organic material and nutrients. We compared extracellular AAO and PH rates to C and N uptake rates along estuarine gradients of salinity, nutrients and productivity in the Pocomoke River, a subestuary of the Chesapeake Bay. This estuary is seasonally depleted in inorganic N, and rich in dissolved organic material (DOM) throughout the year. AAO, PH, and N uptake rates measured in 1999 and 2000 were not limited to particular size fractions measured, or to auto- or heterotrophic groups of organisms. At a station near the turbidity …

The Role Of Physical, Chemical, And Microbial Heterogeneity On The Field-Scale Transport And Attachment Of Bacteria, Brian J. Mailloux, Mark E. Fuller, Tullis C. Onstott, James Hall, Hailiang Dong, Mary F. Deflaun, Sheryl H. Streger, Randi K. Rothmel, Maria Green, Donald J. P. Swift, Jon Radke

OES Faculty Publications

A field-scale bacterial transport experiment was conducted at the Narrow Channel Focus Area of the South Oyster field site located in Oyster, Virginia. The goal of the field experiment was to determine the relative influence of subsurface heterogeneity and microbial population parameters on flow direction, velocity, and attachment of bacteria at the field scale. The field results were compared with results from laboratory-scale column experiments to develop a method for predicting field-scale bacterial transport. The field site is a shallow, sandy, unconfined, aerobic aquifer that has been characterized by geophysical, sedimentological, and hydrogeological methods. Comamonas sp. strain DA001 and a …

The Composition Of Fatty Acids In Hypericum Scabrum, H. Scabroides And H. Amblysepalum, Hasan Çeti̇n Özen, Mehmet Başhan

Turkish Journal of Chemistry

The chemical composition of the fatty acid methyl esters (FAMEs) of flowering tops of Hypericum scabrum, H. scabroides and H. amblysepalum were identified by gas chromatography. In this work 5 FAMEs for H. scabrum, 9 FAMEs for H. scabroides and 8 FAMEs for H. amblysepalum were identified. The major components were alpha-linolenic (48.60%), linoleic (32.53%) and oleic (11.45%) acids in H. scabrum. Alpha-linolenic (29.84%), palmitic (27.90%) and oleic (16.49%) acids were present in H. scabroides and alpha linolenic (41.79%) and palmitic acids (32.28%) were found in H. amblysepalum.

Neolignan, Flavonoid, Phenylethanoid And Iridoid Glycosides From Phlomis Integrifolia, İclal Saracoğlu, Mehtap Varel, İhsan Çaliş, Ali̇ Arslan Dönmez

Turkish Journal of Chemistry

From the aerial parts of Phlomis integrifolia Hub.-Mor. (Lamiaceae) were isolated a neolignan glucoside, dehyrodiconiferyl alcohol-4-O-\beta -D-glucopyranoside (1), an ester flavone glycoside, chrysoeriol 7-O-(3''-O-trans-p-coumaroyl)-\beta -D-glucopyranoside (2), four phenylethanoid glycosides, forsythoside B (3), verbascoside (=acteoside) (4), leucosceptoside A (5) and martynoside (6) along with an iridoid glucoside, lamiide (7). The structure elucidation of the isolated compounds was carried out by spectroscopic (UV, IR, 1D- and 2D-NMR) methods. The isolation of neolignan glucoside dehyrodiconiferyl alcohol-4-O-\beta -D-glucopyranoside (1) is reported for the first time from a Phlomis species as well as for the family Lamiaceae.

An Efficient Synthesis Of Alnustone, A Naturally Occurring Compound, Süleyman Göksu, Hülya Çeli̇k, Hasan Seçen

Turkish Journal of Chemistry

Alnustone, 4(E),6(E)-1,7-diphenyl-hepta-4,6-dien-3-one, was synthesized starting from benzaldehyde in three steps with an overall yield of 57%. The condensation of benzaldehyde with acetone gave benzalacetone. The Pd-C catalyzed hydrogenation of benzalacetone afforded benzylacetone. The in situ enamination of benzylacetone with pyrrolidine and acetic acid followed by cinnamaldehyde treatment gave alnustone.

Changes In Chlorophyll-Carotenoid Contents, Antioxidant Enzyme Activities And Lipid Peroxidation Levels In Zn-Stressed Mentha Pulegium, Ni̇lgün Candan, Leman Tarhan

Turkish Journal of Chemistry

The relationships between chlorophyll-carotenoid contents, the antioxidant enzyme activities, such as superoxide dismutase (SOD), catalase (CAT), ascorbate-dependent peroxidase (AsA-dep POD) and guaiacol-dependent peroxidase (Gua-dep POD), and lipid peroxidation (LPO) levels were investigated in leaves at different positions of M. pulegium grown in nutrient medium containing 0-1 \mu M Zn. The maximum chlorophyll-carotenoid content's SOD and CAT activities and the minimum LPO level were observed in leaf 6 at 7.6 10^{-2} \mu M Zn (as control). While chlorophyll-carotenoid contents in the absence of Zn were lower than those of the control, SOD and CAT activities significantly increased with decreasing Zn concentration. …

Determination Of H_{2}O_{2} Content Of Various Water Samples Using A Chemiluminescence Technique, Tuğba Tüğsüz, Elmas Gök, Serdar Ateş

Turkish Journal of Chemistry

Hydrogen peroxide (H_{2}O_{2}) plays an important role in natural water samples. In this study H_{2}O_{2} concentrations were quantified in different water samples by chemiluminescence detection. This method was chosen because of its high sensitivity and suitability for determining low concentrations of H_{2}O_{2}. H_{2}O_{2} is introduced to the oxidation reaction of alkaline luminol solutions in the presence of Co^{2 + } ion catalyst. When these components are mixed, blue light (\lambda = 440 nm) is emitted. Maximum chemiluminescence intensity occurs within 2 s after mixing and is continuous for up to a few minutes, permitting accurate measurements at selected delay times. …

Trading Agents Competing: Performance, Progress And Market Effectiveness, Michael P. Wellman, Shih-Fen Cheng, Daniel M. Reeves, Kevin M. Lochner

Research Collection School Of Computing and Information Systems

The annual trading agent competition offers agent designers a forum for evaluating programmed trading techniques in a challenging market scenario. TAC aims to spur research by enabling researchers to compare techniques on a common problem and build on each other's ideas. A fixed set of assumptions and environment settings facilitates communication of methods and results. As a multiyear event, TAC lets researchers observe trading agents' progress over time, in effect accelerating the evolution of an adapted population of traders. Given all the participant effort invested, it is incumbent on us to learn as much from the experience as possible. After …

A Study Of Elementary Teachers' Abilities, Attitudes, And Beliefs About Problem Solving, Nancy Mullins Brown

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

Problem solving has been alternately viewed as the justification for the study of mathematics or as the impetus and means for studying mathematics. This study examines characteristics—attitudes toward problem solving, beliefs about problem solving, and abilities to solve problems—of elementary teachers of grades three, four, and five that relate to problem solving.

Participants completed a two-part survey to quantify their attitudes and beliefs and a problem-solving activity which quantified their problem-solving abilities. Four participants were subsequently interviewed. Analyses showed that these teachers had generally positive attitudes toward problem solving, generally positive beliefs about problem solving, and generally poor problem-solving abilities. …

An Inquiry Into Gardner's Theory Of Multiple Intelligences And Strengths Of Students Placed In Special Education Under Mildly Disabled Categories, Kathryn Sandiford Harrell

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

This study explored the strengths displayed by 4th-5th grade students placed in special education under mildly disabled categories as compared to the intelligences defined by Howard Gardner in his Theory of Multiple Intelligences (Gardner, 1983, 1999). These categories consist of Specific Learning Disabilities (SLD) and Mildly Intellectually Disabled (MUD). Critics maintain that special education has been focused on the weaknesses of students while overlooking their strengths (Miller, 1993; Armstrong, 2000). Under new legislation and new performance goals for special education, the time has come to focus on students' strengths and equal opportunities for students to learn the curriculum mandated by …

Faculty Senate Librarian's Report-2003, Georgia Southern University

Faculty Senate: Librarian's Reports

No abstract provided.

Georgia Southern University Fact Book, Georgia Southern University

Georgia Southern Fact Books (1976-2022)

No abstract provided.

Advances In Mobile Commerce Technologies, Ee Peng Lim, Keng Siau

Research Collection School Of Computing and Information Systems

No abstract provided.