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Articles 29071 - 29100 of 34711

Full-Text Articles in Physical Sciences and Mathematics

Impedance Measurements Of Polyester-Coated Galvanised Mild Steel In 10xacid Rainwater After An Accelerated Wet-Dry Test, İlyas Dehri̇ Jan 2000

Impedance Measurements Of Polyester-Coated Galvanised Mild Steel In 10xacid Rainwater After An Accelerated Wet-Dry Test, İlyas Dehri̇

Turkish Journal of Chemistry

The variation of defective polyester-coated performance with time in 10xacid rain solution was investigated using electrochemical impedance spectroscopy. Measurements were carried out on samples after an accelerated atmospheric corrosion test. The impedance diagrams (Nyquist plots) were simulated using the EQUIVCRT program which was elaborated by Boukamp and the semi-ellipse model which was developed by Erbil. It has been shown that the defective coating resistance changes with time for the samples subjected to acid rainwater. The corrosion rate of coated metal also changes with time.

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Synthesis Of A New Dihydropyridine Derivative Containing A Known Vasodilator Khellin, Gülgün Ayhan Kilcigi̇l, Meral Tunçbi̇lek, Rahmi̇ye Ertan, Kevser Erol, Engi̇n Yildirim Jan 2000

Synthesis Of A New Dihydropyridine Derivative Containing A Known Vasodilator Khellin, Gülgün Ayhan Kilcigi̇l, Meral Tunçbi̇lek, Rahmi̇ye Ertan, Kevser Erol, Engi̇n Yildirim

Turkish Journal of Chemistry

The synthesis and spasmolytic activity of a novel dihydropyridine derivative which contains a vasodilator furanochromone khellin at the 4^{th}$ position of the dihydropyridine ring via the Hantzsch method from khellin-2-carboxaldehyde is described.

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The Effect Of Acetone On Calomel Formation On A Mercury Film Electrode Surface In Chloride Medium, F. Ni̇l Ertaş, H. İsmet Gökçel, Hüseyi̇n Tural Jan 2000

The Effect Of Acetone On Calomel Formation On A Mercury Film Electrode Surface In Chloride Medium, F. Ni̇l Ertaş, H. İsmet Gökçel, Hüseyi̇n Tural

Turkish Journal of Chemistry

In the presence of chloride ions, calomel formation takes place on the mercury thin film electrodes under open-circuit conditions, which leads to high base currents and erratic performance in ASV meas- urements. This study describes the effect of chloride concentration on the calomel formation on the surface by following the cathodic peak on the anodic scan. The effect of acetone on the surface reaction and baseline stability was studied. Application of the method with a sea water sample is also given.

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Modification Of Polyester And Polyamide Fabrics By Different In Situ Plasma Polymerization Methods, T. Öktem, N. Seventeki̇n, H. Ayhan, Erhan Pi̇şki̇n Jan 2000

Modification Of Polyester And Polyamide Fabrics By Different In Situ Plasma Polymerization Methods, T. Öktem, N. Seventeki̇n, H. Ayhan, Erhan Pi̇şki̇n

Turkish Journal of Chemistry

In order to increase the hydrophilicities, and therefore to impart soil resistance and to improve dyeability, poly(ethylene terephthalate) (PET) and polyamide (PAm) fabrics were treated in low-temperature plasmas. Five different modification types were applied. Fabrics were directly treated in acrylic acid, water, air, O_2 and argon plasma. The plasma conditions (i.e., exposure time and discharge power) were changed to control the extent of plasma surface modification. Wettability, soil resistance and dyebility of PET fabrics were significantly improved by this method. More hydrophilic surfaces were created by all the methods.

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Spectrophotometric Determination Of Selenium (Iv) Using Methdilazine Hydrochloride, Mahaveer B. Melwanki, Jaldappa Seetharamappa Jan 2000

Spectrophotometric Determination Of Selenium (Iv) Using Methdilazine Hydrochloride, Mahaveer B. Melwanki, Jaldappa Seetharamappa

Turkish Journal of Chemistry

Methdilazine hydrochloride is proposed as a selective and sensitive reagent for the spectrophotometric determination of selenium (IV). The reagent forms a red radical cation by selenimum (IV) in hydrochloric acid medium and exhibits an absorption maximum at 513 nm. Beer's law is valid over the concentration range 0.1-2.3 mg1^{-1} of selenium (IV). Sandell's sensitivity of the reaction is found to be 3.57 ng cm^{-2} and the molar extinction coefficient is 9.32 x 10^4 1 mol^{-1} cm^{-1} at 513 nm. The effects of acidity, reagent concentration, temperature and diverse ions upon the absorbance of the red species are critically assessed. The …

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Polarographic Determination Of Fluvoxamine Maleate In Tablets, Fi̇kri̇ye Elmali, Güzi̇n Alpdoğan, Sidika Sungur, Şule Aycan Jan 2000

Polarographic Determination Of Fluvoxamine Maleate In Tablets, Fi̇kri̇ye Elmali, Güzi̇n Alpdoğan, Sidika Sungur, Şule Aycan

Turkish Journal of Chemistry

The differential pulse polarographic (DPP) method was developed for the determination of fluvoxamine maleate (I). At pH = 3. 7, (I) give a peak at - 0. 73 V in aqueous solution. The developed method was applied to the assay of the drug substance in commercial tablet formulations. The results were statistically compared with those obtained by reference methods (HPLC and direct current polarographic method) using t- and F- tests at 95 % confidence level.

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Electroreduction Of Some Diazine And Triazine Pesticides At The Dropping Mercury Electrode, Petr Zuman, Marina Privman, Masami Shibata, Jiri Ludvik Jan 2000

Electroreduction Of Some Diazine And Triazine Pesticides At The Dropping Mercury Electrode, Petr Zuman, Marina Privman, Masami Shibata, Jiri Ludvik

Turkish Journal of Chemistry

Electroanalytical methods enable determination of electroactive species in nonhomogeneous systems, as limiting currents are little affected by the presence of solid and colloidal particles. An example of such applications of electrochemical methods are studies of binding of toxic substances, such as pesticides, on slightly soluble polymers, such as lignin. To successfully apply polarographic methods for following free pesticides in a slurry of lignin, it is first necessary in principle to elucidate the electrochemical processes involved. In aqueous buffered solutions the electron transfers, in which organic compounds participate, are in the majority of cases accompanied by chemical reactions. To elucidate the …

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Synthetic Metal Alloys: Preparation Of Polyaniline/Polypyrrole Alloys In Protic Medium, Fati̇h Köleli̇, Meltem Düdükcü, Yasemi̇n Arslan Jan 2000

Synthetic Metal Alloys: Preparation Of Polyaniline/Polypyrrole Alloys In Protic Medium, Fati̇h Köleli̇, Meltem Düdükcü, Yasemi̇n Arslan

Turkish Journal of Chemistry

Pyrrole and aniline solutions were mixed in different ratios and oxidized under anodic conditions on Pt surface in protic medium. The electrocopolymerization and electrochemical properties of these alloys were investigated. Current-potential diagrams of polyaniline (PA), polypyrrole (PP) and the resulting alloys were recorded and their electrochemical characterizations were identified. In-situ resistance measurements of synthesized alloys were carried out with a home-made apparatus. Conductivity of alloys showed changes depending on applied potential as intrinsic polymers. The electrochemical behaviour of homopolymers and alloys was studied at different temperatures.

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A Convenient Synthesis Of Some 4-(Alkylamino)-4,5-Dihydro-1h-1,2,4-Triazol-5-Ones, Bahi̇tti̇n Kahveci̇, Aykut İki̇zler Jan 2000

A Convenient Synthesis Of Some 4-(Alkylamino)-4,5-Dihydro-1h-1,2,4-Triazol-5-Ones, Bahi̇tti̇n Kahveci̇, Aykut İki̇zler

Turkish Journal of Chemistry

A series of 3-alkyl-4-(arylidenamino)-4,5-dihydro-1H-1,2,4-triazol-5-ones, {\bfseries 6-10,} was obtained from the reaction of the corresponding 3-alkyl-4-amino-4,5-dihydro-1H-1,2,4-triazol-5-ones, {\bfseries 1,} with the appropriate aldehydes. 3-alkyl-4-(alkylamino)-4,5-dihydro-1H-1,2,4-triazol-5-ones of type {\bfseries 11-16} were synthesized from the selective reduction of compounds {\bfseries 5-10} with NaBH$_{4}$ in diglyme or DMSO medium as a general and convenient method.

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Ion-Selective Membrane Electrode For The Determination Of A Novel Phenylpiperazine Antidepressant, Nefazodone, Arzum Erdem, Di̇lşat Özkan, Kağan Kerman, Burcu Meri̇ç, Tayfun Dalbasti, Mehmet Özsöz Jan 2000

Ion-Selective Membrane Electrode For The Determination Of A Novel Phenylpiperazine Antidepressant, Nefazodone, Arzum Erdem, Di̇lşat Özkan, Kağan Kerman, Burcu Meri̇ç, Tayfun Dalbasti, Mehmet Özsöz

Turkish Journal of Chemistry

The construction and performance characteristics of ion-selective membrane electrodes for a newly found phenylpiperazine antidepressant, Nefazodone (NFN), based on its ion-pair complexes with phosphotungstate (PT), tetraphenylborate (TPB), tungstosilicate (TS) and reineckate (RN) in a poly(vinyl chloride) (PVC) matrix are described. The best ion-selective electrode for determination of NFN contains NFN-PT as the active material. This electrode exhibits a Nernstian response (62.6 ± 0.4 mV per decade) in the range 1.5 x 10$^{-5}$ to 1.0 x 10^{-2} M NFN.HCl in solutions. The selectivity of this electrode to NFN in the presence of a number of sugar molecules, cations and drugs is …

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Investigation Of The Synthesis Of Some Dehydroalanine Derivatives, Si̇bel Süzen, John Michael Williams Jan 2000

Investigation Of The Synthesis Of Some Dehydroalanine Derivatives, Si̇bel Süzen, John Michael Williams

Turkish Journal of Chemistry

Dehydroamino acids represent an important class of compound as they are key intermediates in unusual amino acid and in the design of peptides and are constituents of a variety of naturally occurring antibiotic and phytotoxic peptides. In view of the importance of proteins and peptides containing hydroxyamino acids and the problems associated with their synthesis and dehydration, an investigation was performed on model compounds in order to examine the difficulties of the dehydration reactions. The preparation and properties of the model dehydroalanine derivatives have been studied.

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Hplc/Hydride Generation Aas Coupling For The Speciation Of Sb(Iii) And Sb(V) In Wastewaters, Nuray Şatiroğlu, Sema Bektaş, Ömer Genç, Haydar Hazel Jan 2000

Hplc/Hydride Generation Aas Coupling For The Speciation Of Sb(Iii) And Sb(V) In Wastewaters, Nuray Şatiroğlu, Sema Bektaş, Ömer Genç, Haydar Hazel

Turkish Journal of Chemistry

A comparative study was made with two HPLC columns of different lengths (PRP-X 100, 250 mm \( \times \) 4.1 mm id and PRP-X 100, 100 mm \( \times \) 4.1 mm id) coupled to HGAAS for the speciation of inorganic Sb(III) and Sb(V) species. The effects of eluent concentration and pH on the retention times of Sb species in both columns were investigated. The separation of Sb species was realized by using 50 mmol/L citrate solution at pH 4.0 as the eluent. The retention times were 2.0 min and 10.0 min in the 250 mm column, and 1.4 min …

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Zinc Determination In Pleural Fluid, Nazan Demi̇r, Yaşar Demi̇r, Ebubeki̇r Bakan, İrfan Küfrevi̇oğlu Jan 2000

Zinc Determination In Pleural Fluid, Nazan Demi̇r, Yaşar Demi̇r, Ebubeki̇r Bakan, İrfan Küfrevi̇oğlu

Turkish Journal of Chemistry

In this study, an enzymatic zinc determination method was applied to pleural fluid, the basis of which was the regaining of the activity of apo carbonic anhydrase by the zinc present in the sample. The method was used for pleural fluid zinc determination in order to show the application to body fluids other than serum. For this purpose, pleural fluids were obtained from 20 patients and zinc concentrations were determined. Carbonic anhydrase was purified by affinity chromatography from bovine erythrocytes. The zinc present in its structure was removed by dialysis against dipicolinic acid, resulting in apoenzyme obtained at a ratio …

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X-Ray Powder Diffraction And Ir Study Of Calcium Borophosphate Cabpo_5, A. Baykal, G. Gözel, Meral Kizilyalli, M. Toprak, R. Kniep Jan 2000

X-Ray Powder Diffraction And Ir Study Of Calcium Borophosphate Cabpo_5, A. Baykal, G. Gözel, Meral Kizilyalli, M. Toprak, R. Kniep

Turkish Journal of Chemistry

In this study, CaBPO_5 was synthesized by different solid state reactions than reported before and its X-ray powder diffraction and IR data were reported. In one of these solid state reactions BPO_4 was used as a phosphating agent. The examination of the X-ray powder diffraction data showed that this compound crystallized in a hexagonal system and the refined unit cell parameters were a = 6.684, c = 6.616(2) \AA, with Z=3 as reported before. From the observed reflections, the space group was determined as P3_121, and its density was found to be 3.15 g/cc. The X-ray powder diffraction and IR …

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All Solid-State Contact Lead(Ii) Ion-Selective Pvc Membrane Electrode Using Dimethylene Bis(4-Methylpiperidinedithiocarbamate) Neutral Ionophore, İbrahi̇m Işildak Jan 2000

All Solid-State Contact Lead(Ii) Ion-Selective Pvc Membrane Electrode Using Dimethylene Bis(4-Methylpiperidinedithiocarbamate) Neutral Ionophore, İbrahi̇m Işildak

Turkish Journal of Chemistry

All solid-state contact PVC membrane electrodes for lead(II) ion were developed by using dimethylene bis(4-methylpiperidinedithiocarbamate) as neutral carrier and nitrophenyloctyl ether or dioctylsebacate as plasticizers. Response properties of the all solid-state contact PVC membrane electrode prepared with nitrophenyloctyl ether were better than those of the membrane electrode prepared with dioctylsebacate. The nitrophenyloctyl ether plasticized the all solid-state contact PVC membrane electrode and exhibited a good linear response of 30 mV/decade for lead(II) ion within the concentration ranges \( 0.1-5\times10^{-6} \) mol dm\( ^{-3} \) lead(II) nitrate, good selectivity over alkali, alkali-earth and transition metal ions including copper(II) ion by a …

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Computerised Evaluation Of Cognitive And Motor Function, B. Kisačanin, G. C. Agarwal, J. Taber, D. (Daniel) Hier Jan 2000

Computerised Evaluation Of Cognitive And Motor Function, B. Kisačanin, G. C. Agarwal, J. Taber, D. (Daniel) Hier

Chemistry Faculty Research & Creative Works

In This Paper, We Present a Clinical Study of Computerized Tracking in the Evaluation of Cognitive and Motor Function. We Investigate its Use in the Assessment of Effectiveness of Antiepileptic Drugs (AEDs) as Well as in the Process of Following the Progress of Alzheimer's Disease (AD). to Simplify the Experiments, We Introduce Real-Time Adaptation of the Target Speed. in the Study with Epileptic Patients, Three Result Groups Are Compared: Blood Levels of AEDs, Scores on Standard Neuropsychological Tests, and Scores on Computerized Tracking and Reaction Time Tests. It is Found that the Computerized Tests Are Repeatable, Reliable and Sensitive and …

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Application Of Electron-Attachment Reactions To Enhance Selectivity Of Electron-Capture Detector For Nitroaromatic Explosives, Mark Gehrke, Shubhender Kapila, V. J. Flanigan Jan 2000

Application Of Electron-Attachment Reactions To Enhance Selectivity Of Electron-Capture Detector For Nitroaromatic Explosives, Mark Gehrke, Shubhender Kapila, V. J. Flanigan

Chemistry Faculty Research & Creative Works

The differences in the extent of electron-attachment reactions between thermal electrons and selected classes of organic molecules with high electron affinities were investigated. the investigations showed that interactions of thermal electrons with nitroaromatic compounds lead to the formation of neutral products with very low electron affinities. by contrast, a number of other analytes with high electron affinities such as polyhalogenated organic compounds, lead to products with high electron affinities. This difference was exploited to differentiate between nitroaromatic and polychlorinated organic compounds with a tandem arrangement consisting of two electron-capture detectors connected in series with an electron-attachment reactor.

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Dynamics Of Interfacial Polymers In Composites, Frank D. Blum, Wuu-Yung Lin Jan 2000

Dynamics Of Interfacial Polymers In Composites, Frank D. Blum, Wuu-Yung Lin

Chemistry Faculty Research & Creative Works

Much experimental and theoretical work has been done on the behavior of adsorbed polymers. However, not much work has focused on the dynamics, especially segmental dynamics, of the adsorbed polymers. This is especially true of filled polymer or composite systems as the interfacial layers in these systems are difficult to study with most techniques. NMR is not restricted to use in optically clear samples and its use in the characterization in the surface polymers has been reviewed. In our laboratory, we have found that deuterium NMR could be used to probe the segmental dynamics of adsorbed polymers. The position of …

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Pyrolysis-Mass Spectrometry For Rapid Classification Of Oysters According To Rearing Area, J. Krupcík, P. Oswald, I. Spánik, P. Májek, M. Bajdichová, P. Sandra, Daniel W. Armstrong Jan 2000

Pyrolysis-Mass Spectrometry For Rapid Classification Of Oysters According To Rearing Area, J. Krupcík, P. Oswald, I. Spánik, P. Májek, M. Bajdichová, P. Sandra, Daniel W. Armstrong

Chemistry Faculty Research & Creative Works

Current concern for the safety and traceability of food, as well as the desire of oyster farmers, for marketing reason, to emphasize the geographical origin of their production, requires new methods to make possible a real product identification. In this study, 181 oyster samples were analyzed to determine their origin area. These samples were collected in nine French rearing areas at four different times of the year (spring, summer, and the beginning and end of autumn) and from four to eight sites in each area to provide a variability parameter. Analysis of fingerprints after Curie point pyrolysis-mass spectrometry, by an …

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Bismuth(Iii) Oxide Perchlorate Promoted Rearrangement Of Epoxides To Aldehydes And Ketones, Ram Mohan, Andrew Anderson, Jesse Blazek, Parie Garg, Brian Payne Jan 2000

Bismuth(Iii) Oxide Perchlorate Promoted Rearrangement Of Epoxides To Aldehydes And Ketones, Ram Mohan, Andrew Anderson, Jesse Blazek, Parie Garg, Brian Payne

Scholarship

Aryl-substituted epoxides and aliphatic epoxides with a tertiary epoxide carbon undergo smooth rearrangement in the presence of 10–50 mol% bismuth(III) oxide perchlorate, BiOClO4•xH2O, to give carbonyl compounds. The rearrangement is regioselective with aryl substituted epoxides and a single carbonyl compound arising from cleavage of benzylic C―O bond is formed. BiOClO4•xH2O is relatively non-toxic, insensitive to air and inexpensive, making this catalyst an attractive alternative to more corrosive and toxic Lewis acids such as BF3•Et2O or InCl3 currently used to effect epoxide rearrangements.

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The Discovery-Oriented Approach To Organic Chemistry. 3. Boron-Trifluoride Catalyzed Rearrangement Of Cis- And Trans-Stilbene Oxides. An Exercise In 1H Nmr Spectroscopy For Sophomore Organic Laboratories, Ram Mohan, Erik Sgariglia, Regina Schopp, Kostas Gavardinas Jan 2000

The Discovery-Oriented Approach To Organic Chemistry. 3. Boron-Trifluoride Catalyzed Rearrangement Of Cis- And Trans-Stilbene Oxides. An Exercise In 1H Nmr Spectroscopy For Sophomore Organic Laboratories, Ram Mohan, Erik Sgariglia, Regina Schopp, Kostas Gavardinas

Scholarship

Epoxides, or oxiranes, are among the most versatile intermediates in organic synthesis. Yet very few examples of laboratory experiments involving reactions of epoxides are to be found in lab texts. We have developed a discovery-oriented laboratory experiment that involves the rearrangement of both cis- and trans-stilbene oxides with boron trifluoride etherate. The identity of the product can be easily determined by 1H NMR spectroscopy and, in case of the trans isomer, by preparation of the semicarbazone derivative as well. In spite of the simplicity of the experiment, the element of discovery ensures that student interest and enthusiasm are retained.

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Microhollow Cathode Discharge Excimer Lamps, Karl H. Schoenbach, Ahmed El-Habachi, Mohamed M. Moselhy, Wenhui Shi, Robert H. Stark Jan 2000

Microhollow Cathode Discharge Excimer Lamps, Karl H. Schoenbach, Ahmed El-Habachi, Mohamed M. Moselhy, Wenhui Shi, Robert H. Stark

Bioelectrics Publications

Microhollow cathode discharges are high-pressure, nonequilibrium gas discharges between a hollow cathode and a planar or hollow anode with electrode dimensions in the 100 μm range. The large concentration of high-energy electrons, in combination with the high-gas density favors excimer formation. Excimer emission was observed in xenon and argon, at wavelengths of 128 and 172 nm, respectively, and in argon fluoride and xenon chloride, at 193 and 308 nm. The radiant emittance of the excimer radiation was found to increase monotonically with pressure. However, due to the decrease in source size with pressure, the efficiency (ratio of excimer radiant power …

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On-Road Remote Sensing Of Automobile Emissions In The Chicago Area: Year 3, Sajal S. Pokharel, Gary A. Bishop, Donald H. Stedman Jan 2000

On-Road Remote Sensing Of Automobile Emissions In The Chicago Area: Year 3, Sajal S. Pokharel, Gary A. Bishop, Donald H. Stedman

Fuel Efficiency Automobile Test Publications

No abstract provided.

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The Effects Of Substituting Iron For Manganese In Smmn₆Ge₆: Magnetic And Crystallographic Properties, J. Han, William B. Yelon, Naushad Ali, I. Dubenko, G. K. Marasinghe, Ph. I'Héritier, William Joseph James Jan 2000

The Effects Of Substituting Iron For Manganese In Smmn₆Ge₆: Magnetic And Crystallographic Properties, J. Han, William B. Yelon, Naushad Ali, I. Dubenko, G. K. Marasinghe, Ph. I'Héritier, William Joseph James

Physics Faculty Research & Creative Works

No abstract provided.

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The Puzolana Obsidian Source: Locating The Geologic Source Of Ayacucho Type Obsidian, Richard L. Burger, Michael D. Glascock Jan 2000

The Puzolana Obsidian Source: Locating The Geologic Source Of Ayacucho Type Obsidian, Richard L. Burger, Michael D. Glascock

Andean Past

No abstract provided.

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Editor's Preface Andean Past 6, Monica Barnes Jan 2000

Editor's Preface Andean Past 6, Monica Barnes

Andean Past

No abstract provided.

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Photochemical Processes And Accumulation Of Solar Energy In Oil Luminophors, A. P. Mamedov, M. I. Rustamov, R. A. Dzhafarova, Ch. K. Salmanova Jan 2000

Photochemical Processes And Accumulation Of Solar Energy In Oil Luminophors, A. P. Mamedov, M. I. Rustamov, R. A. Dzhafarova, Ch. K. Salmanova

Turkish Journal of Chemistry

Using the methods of absorption spectroscopy, luminescence and EPR there has been studied the mechanism of solar energy accumulation by high boiling products of oil refining and by luminophors prepared on their basis within wide temperature range (77-550 K). The photochemical processes with participation of all main components of oil products and luminophors have been considered. The mechanisms of accumulation of solar energy of the studied products and luminophors have been considered. The mechanism of accumulation of solar energy of the studied products prior and above their pour points have been found to differ significantly. The light energy accumulation and …

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Auxiliary Controlled Intramolecular 1,3-Dipolar Cycloaddition Reactions Of Chiral Azomethine Ylides, Özdemi̇r Doğan, Philip P. Garner Jan 2000

Auxiliary Controlled Intramolecular 1,3-Dipolar Cycloaddition Reactions Of Chiral Azomethine Ylides, Özdemi̇r Doğan, Philip P. Garner

Turkish Journal of Chemistry

Intramolecular 1,3-dipolar cycloaddition reactions of chiral azomethine ylides obtained by thermal ring opening of chiral aziridines 7a, b and 8a, b are investigated. Synthesis of these aziridines 7a, b and 8a, b is described.

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Effect Of Non-Ionic Reagent Adsorption On Zeta Potential Of Fine Coal Particles, Zeki̇ Aktaş Jan 2000

Effect Of Non-Ionic Reagent Adsorption On Zeta Potential Of Fine Coal Particles, Zeki̇ Aktaş

Turkish Journal of Chemistry

The -5 \mum size fractions of two low rank British coals were used in zeta potential measurements. The electrophoretic behaviour was described by the Helmholtz-Smoluchowski equation. The non-ionic reagents used for the adsorption tests were of diacetone alcohol and 2-ethyl hexanol. Zeta potentials of both coals at various pHs were significantly different in the absence of the non-ionic reagents. Negligible variations were observed on the zeta potential curves of both coal particles in the presence of the non-ionic reagents used. It was concluded that the pH of coal particles in slurry is a principle parameter controlling the value of zeta …

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An Efficient Synthesis Of (1 S , 2 R )-1-Amino-2-Indanol, A Key Intermediate Of Hiv Protease Inhibitor, Indinavir, Ayhan S. Demi̇r, Hi̇lal Aksoy-Cam, Nuretti̇n Camketen, Haluk Hamamci, Fatoş Doğanel Jan 2000

An Efficient Synthesis Of (1 S , 2 R )-1-Amino-2-Indanol, A Key Intermediate Of Hiv Protease Inhibitor, Indinavir, Ayhan S. Demi̇r, Hi̇lal Aksoy-Cam, Nuretti̇n Camketen, Haluk Hamamci, Fatoş Doğanel

Turkish Journal of Chemistry

(1S,2R)-1-amino-2-indanol, a key component of an HIV protease inhibitor is synthesized in four steps starting from indanone. The Mn(OAC)_3 mediated acetoxylation of indanone followed by fungus catalyzed hydrolysis of acetoxyindanone furnished optically pure \alpha-hydroxy indanone. Formation and enantioselective reduction of oxime ether of 2-hydroxyindanone afforded (1S, 2R)-1-amino-2-indanol in 97% {\it cis} selectivity.

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