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Articles 2161 - 2190 of 2555
Full-Text Articles in Physical Sciences and Mathematics
Using Spatial Systems To Establish Priorities For Catchment Management, David Deeley, David Weaver, J Hick
Using Spatial Systems To Establish Priorities For Catchment Management, David Deeley, David Weaver, J Hick
Conference papers and presentations
Priorities for catchment management can be established based on either, an objective assessment of relative priorities throughout the catchment, or by simply responding to crises associated with particular land uses and their sectional interests. While the latter method can have advantages in terms of establishing community good will, team cohesion, and a sense of achievement for particular sectional interests, it may have shortcomings in terms of a more objective and rational assessment of the relative magnitude and hence priority of land management problems. Spatial modelling using GIS can form the basis for developing a catchment-wide understanding of the relative importance …
Surface Resistance Measurements Of Superconducting Niobium Samples With A Triaxial Cavity, Paul Martin Boccard
Surface Resistance Measurements Of Superconducting Niobium Samples With A Triaxial Cavity, Paul Martin Boccard
Physics Theses & Dissertations
This experimental study has revealed and investigated many of the physical issues that affect accurate measurement of the surface resistance for small samples consisting of superconducting niobium films on copper substrates. It is believed that this work provides the groundwork for future research directed towards solving this important problem. Accurate measurement of surface resistance for such samples is needed to allow the rapid evaluation and optimization of the deposition parameters necessary for manufacturing low-loss superconducting niobium films.
A superconducting niobium triaxial cavity was investigated to determine its suitability for measuring the residual surface resistance of copper samples that were sputter-coated …
Chemistry Of Maceral And Groundmass Density Fractions Of Torbanite And Cannel Coal, Zhiwen Han, Michael A. Kruge
Chemistry Of Maceral And Groundmass Density Fractions Of Torbanite And Cannel Coal, Zhiwen Han, Michael A. Kruge
Department of Earth and Environmental Studies Faculty Scholarship and Creative Works
Microscopically, torbanite and cannel coal are composed of coarser macerals set in a fine-grained to amorphous groundmass. It is often assumed that the amorphous groundmass is genetically related to the distinct macerals. The separation of macerals and groundmass from 14 late Paleozoic torbanite, cannel, and humic coals permits the analysis of individual constituents using elemental analysis and flash pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS). Cluster and principal component analyses of the Py-GC/MS data further reveal the chemical similarities and differences between the various constituents. Pyrolyzates of Botryococcus-related alginites are characterized by an abundance of normal alkadienes, alkenes, and alkanes. Even their …
A Comparison Of Observations And Model Simulations Of NoX/NoY In The Lower Stratosphere, R. S. Gao, D. W. Fahey, L. A. Del Negro, Stephen G. Donnelly Ph.D., E. R. Keim, J. A. Neuman, E. Teverovskaia, P. O. Wennberg, T. F. Hanisco, E. J. Lanzendorf, M. H. Proffitt, J. J. Margitan, J. C. Wilson, J. W. Elkins, R. M. Stimpfle, R. C. Cohen, C. T. Mcelroy, T. P. Bui, R. J. Salawitch, S. S. Brown, A. R. Ravishankara, R. W. Portmann, M. K.W. Ko, D. K. Weisenstein, P. A. Newman
A Comparison Of Observations And Model Simulations Of NoX/NoY In The Lower Stratosphere, R. S. Gao, D. W. Fahey, L. A. Del Negro, Stephen G. Donnelly Ph.D., E. R. Keim, J. A. Neuman, E. Teverovskaia, P. O. Wennberg, T. F. Hanisco, E. J. Lanzendorf, M. H. Proffitt, J. J. Margitan, J. C. Wilson, J. W. Elkins, R. M. Stimpfle, R. C. Cohen, C. T. Mcelroy, T. P. Bui, R. J. Salawitch, S. S. Brown, A. R. Ravishankara, R. W. Portmann, M. K.W. Ko, D. K. Weisenstein, P. A. Newman
Chemistry Faculty Publications
Extensive airborne measurements of the reactive nitrogen reservoir (NOy) and its component nitric oxide (NO) have been made in the lower stratosphere. Box model simulations that are constrained by observations of radical and long-lived species and which include heterogeneous chemistry systematically underpredict the NOx (= NO + NO2) to NOy ratio. The model agreement is substantially improved if newly measured rate coefficients for the OH + NO2 and OH + HNO3 reactions are used. When included in 2-D models, the new rate coefficients significantly increase the calculated ozone loss due to NOx and modestly change the calculated ozone abundances in …
No(Y) Partitioning From Measurements Of Nitrogen And Hydrogen Radicals In The Upper Troposphere, E. R. Keim, S. A. Mckeen, R. S. Gao, Stephen G. Donnelly Ph.D., R. C. Wamsley, L. A. Del Negro, D. W. Fahey, T. F. Hanisco, E. J. Lanzendorf, M. H. Proffitt, J. J. Margitan, E. J. Hintsa, L. Jaeglé, C. R. Webster, R. D. May, D. C. Scott, R. J. Salawitch, J. C. Wilson, C. T. Mcelroy, E. L. Atlas, F. Flocke, T. P. Bui
No(Y) Partitioning From Measurements Of Nitrogen And Hydrogen Radicals In The Upper Troposphere, E. R. Keim, S. A. Mckeen, R. S. Gao, Stephen G. Donnelly Ph.D., R. C. Wamsley, L. A. Del Negro, D. W. Fahey, T. F. Hanisco, E. J. Lanzendorf, M. H. Proffitt, J. J. Margitan, E. J. Hintsa, L. Jaeglé, C. R. Webster, R. D. May, D. C. Scott, R. J. Salawitch, J. C. Wilson, C. T. Mcelroy, E. L. Atlas, F. Flocke, T. P. Bui
Chemistry Faculty Publications
Recent studies using NO, NO(y), OH and HO2 (HO(X)) observations have postulated acetone and convection of peroxides as significant sources of HO(X) in the upper troposphere (UT). This work focuses on the effect these additional HO(X) sources have on the modeled NO(y) partitioning and comparisons of the modeled NO(x)/NO(y) ratio to observations. The measured NO(x)/NO(y) ratio is usually much higher than predicted regardless of the presence of acetone in the model. The exception occurs for air parcels having low NO(y) and O3 values. For these air parcels the measured NO(x)/NO(y) ratio is much lower than the calculated ratio unless acetone …
Avon And Upper Hotham Region Natural Resource Atlas, Sarah Weaving, Jason Batory
Avon And Upper Hotham Region Natural Resource Atlas, Sarah Weaving, Jason Batory
All other publications
The Avon and Upper Hotham Region Atlas is one of a series of Natural Resource Atlases covering the agricultural region of Western Australia. The purpose of the Atlas is to provide data for local people who manage or have an interest in natural resources. This includes the members of Land Conservation District Committees (LCDC), catchment groups, local government, non-government organisations, conservation groups, schools and libraries.
The aim of this publication is to bring together land and natural resource information from a number of sources and present it in a clear and accessible way. The data covers a number of topics …
Neural Networks In The Analysis Of Water-Soluble Sulfonylurea Herbicides Using An Lc/Ms, Joseph Michael Pompano
Neural Networks In The Analysis Of Water-Soluble Sulfonylurea Herbicides Using An Lc/Ms, Joseph Michael Pompano
Theses and Dissertations
In this research, a hidden node pruning algorithm was developed for an artificial neural network (ANN) that automatically determined a more efficient size of the hidden layer, caused the ANN to resize itself, and then continued to train using a standard back-propagation algorithm. The hidden-node pruning algorithm was based on determining the number of significant eigenvalues present in the matrix of values produced by the hidden layer, starting with an excessive number of hidden nodes.
Eight sulfonylurea herbicides were used as the target analytes in this study. The ability of an ANN to simplify the sample preparation needed for analysis …
Exclusive Disjunctions In Indefinite And Maybe Information In Relational Databases, Taflan İ. Gündem
Exclusive Disjunctions In Indefinite And Maybe Information In Relational Databases, Taflan İ. Gündem
Turkish Journal of Electrical Engineering and Computer Sciences
Incorporating indefinite information into databases has been studied extensively. In this paper, we propose a structure called an E-table to represent maybe information and inclusive and exclusive disjunctions. We define the type of redundancies in E-tables and show how to eliminate them. Also we present an extended relational algebra to operate on E-tables. In this paper we expand the concepts and operations defined by Lin and Sunderraman [1] in order to accommodate exclusive disjunctions in relational databases.
Determination Of The Lep Centre-Of-Mass Energy From Zγ Events, R. Barate, Manoj Thulasidas
Determination Of The Lep Centre-Of-Mass Energy From Zγ Events, R. Barate, Manoj Thulasidas
Research Collection School Of Computing and Information Systems
A study of events with photons and missing energy has been performed with the data sample obtained with the ALEPH detector at centre-of-mass energies from 161 to 184 GeV, corresponding to a total integrated luminosity of about 80 pb−1. The measured distributions are in agreement with Standard Model predictions, leading to constraints on WWγ gauge coupling parameters ∆κγ and λγ. The results from the fit to the cross sections and to the energy and angular distributions of the photons are: ∆κγ = 0.05+1.15 −1.10(stat)±0.25(syst) λγ = −0.05+1.55 −1.45(stat)±0.30(syst).
Measurement Of W-Pair Production In E+E- Collisions At 183 Gev, R. Barate, Manoj Thulasidas
Measurement Of W-Pair Production In E+E- Collisions At 183 Gev, R. Barate, Manoj Thulasidas
Research Collection School Of Computing and Information Systems
The production of W+W− pairs is analysed in a data sample collected by ALEPH at a mean centre-of-mass energy of 182.7 GeV, corresponding to an integrated luminosity of 57 pb−1 . Cross sections are given for different topologies of W decays into leptons or hadrons. Under Standard Model assumptions for the W-pair production and decay, the W-pair cross section is measured to be 15.57 ± 0.62(stat.) ± 0.29(syst.) pb. Using also the W-pair data samples collected by ALEPH at lower centre-of-mass energies, the decay branching ratio of the W boson into hadrons is measured to be B(W → hadrons) = …
Monitoring The Stability Of The Aleph Vertex Detector, G. Sguazzoni, Manoj Thulasidas
Monitoring The Stability Of The Aleph Vertex Detector, G. Sguazzoni, Manoj Thulasidas
Research Collection School Of Computing and Information Systems
The ALEPH Silicon Vertex Detector features an optical fibre laser system to monitor its mechanical stability. The operating principle and the general performance of the laser system are described. The experience obtained during 1997 and 1998 operations confirms the important role that such a system can have with respect to the detector alignment requirements. In particular, the laser system has been used to monitor short-term temperature-related effects and long-term movements. These results and a description of the laser-based alignment correction applied to the 1998 data are presented.
Search For Invisible Higgs Boson Decays In E+E- Collisions At Centre-Of-Mass Energies Up To 184 Gev, R. Barate, Manoj Thulasidas
Search For Invisible Higgs Boson Decays In E+E- Collisions At Centre-Of-Mass Energies Up To 184 Gev, R. Barate, Manoj Thulasidas
Research Collection School Of Computing and Information Systems
In a data sample of 78.3 pb−1 collected in 1996 and 1997 by the ALEPH detector at centre-of-mass energies from 161 to 184 GeV, invisible decays of a Higgs boson have been searched for in the reaction e+e− → hZ, where the Z can decay into e+e−, µ+µ− or q¯q. No evidence for a signal is found and limits on the production cross section are derived as a function of the Higgs boson mass. These results are combined with those obtained in an update of the analyses of the ALEPH data taken at LEP 1. For a production cross section …
Measurement Of The W Mass In E+E- Collisions At 183 Gev, Barate, R.; Et Al., M. Thulasidas
Measurement Of The W Mass In E+E- Collisions At 183 Gev, Barate, R.; Et Al., M. Thulasidas
Research Collection School Of Computing and Information Systems
The mass of the W boson is obtained from reconstructed invariant mass distributions in W-pair events. The sample of W pairs is selected from 57 pb−1 collected with the ALEPH detector in 1997 at a centre-of-mass energy of 183 GeV.
Search For Charged Higgs Bosons In E+E- Collisions At √S = 181-184 Gev, Barate, R.; Et Al., M. Thulasidas
Search For Charged Higgs Bosons In E+E- Collisions At √S = 181-184 Gev, Barate, R.; Et Al., M. Thulasidas
Research Collection School Of Computing and Information Systems
No abstract provided.
One-Prong Τ Decays With Kaons, R. Barate, M. Thulasidas
One-Prong Τ Decays With Kaons, R. Barate, M. Thulasidas
Research Collection School Of Computing and Information Systems
One-prong ττ decays into final states involving kaons are studied with about 161 000 τ+τ−τ+τ− events collected by the ALEPH detector from 1991 to 1995. Charged kaons are identified by dE/dx measurement, while K0LKL0's are detected through their interaction in calorimeters. Branching ratios are measured for the inclusive mode, B(τ−→K−Xντ)=(1.52±0.04±0.04)%B(τ−→K−Xντ)=(1.52±0.04±0.04)%, where X can be any system of neutral particles, and for the exclusive modesB(τ−→K−ντ)=(6.96±0.25±0.14)×10−3,B(τ−→K−π0ντ)=(4.44±0.26±0.24)×10−3,B(τ−→K−π0π0ντ)=(0.56±0.20±0.15)×10−3,B(τ−→K−π0π0π0ντ)=(0.37±0.21±0.11)×10−3,B(τ−→K−K0ντ)=(1.62±0.21±0.11)×10−3,B(τ−→K−K0π0ντ)=(1.43±0.25±0.15)×10−3,B(τ−→K0¯¯¯¯¯¯¯π−ντ)=(9.28±0.45±0.34)×10−3,B(τ−→K0¯¯¯¯¯¯¯π−π0ντ)=(3.47±0.53±0.37)×10−3,B(τ−→K−ντ)=(6.96±0.25±0.14)×10−3,B(τ−→K−π0ντ)=(4.44±0.26±0.24)×10−3,B(τ−→K−π0π0ντ)=(0.56±0.20±0.15)×10−3,B(τ−→K−π0π0π0ντ)=(0.37±0.21±0.11)×10−3,B(τ−→K−K0ντ)=(1.62±0.21±0.11)×10−3,B(τ−→K−K0π0ντ)=(1.43±0.25±0.15)×10−3,B(τ−→K0¯π−ντ)=(9.28±0.45±0.34)×10−3,B(τ−→K0¯π−π0ντ)=(3.47±0.53±0.37)×10−3,where the first error is statistical and the second is systematical. Upper limits for B(τ−→K0¯¯¯¯¯¯¯π−π0π0ντ)B(τ−→K0¯π−π0π0ντ) and B(τ−→K−K0π0π0ντ)B(τ−→K−K0π0π0ντ) are also obtained. Mass spectra in the final states are investigated in order to study the relevant dynamics.
Impedance Characteristics Of Conducting Polypyrrole-Poly(Ethylvinylether) Graft Films, E. Kalaycioğlu, Levent Toppare, T. Grchev, M. Cvetkovska, Y. Yağci
Impedance Characteristics Of Conducting Polypyrrole-Poly(Ethylvinylether) Graft Films, E. Kalaycioğlu, Levent Toppare, T. Grchev, M. Cvetkovska, Y. Yağci
Turkish Journal of Chemistry
Impedance characterization of graft copolymers of poly(2-(N-pyrrolyl)ethylvinylether) and polypyrrole (doped with BF_4^-) was elucidated in comparison with pure polypyrrole doped with BF_4^-.
^{13}C-And ^{31}P-Nmr Study Of Tetracarbonylbis(Diphenylphosphino)Alkanemetal(0) Complexes Of The Group 6 Elements, Zahi̇de Özer, Sai̇m Özkar
^{13}C-And ^{31}P-Nmr Study Of Tetracarbonylbis(Diphenylphosphino)Alkanemetal(0) Complexes Of The Group 6 Elements, Zahi̇de Özer, Sai̇m Özkar
Turkish Journal of Chemistry
Tetracarbonylbis(diphenylphosphino)alkanemetal(0) complexes of the general formula M(CO)_4[(C_6H_5)_2P (CH_2)_nP(C_6H_5)_2] (M: Cr, Mo, W; n: 1, 2, 3) were synthesized from the reaction of M(CO)_4(\eta^{2:2}-1,5-cyclooctadiene) with the appropriate ligand and characterized by means of IR and NMR (^{13}C and ^{31}P) spectroscopy. Spectroscopic data shows that two phosphorus atoms in the complexes are identical and occupy two cis-coordiantion sites in a pseudo-octahedral coordination sphere of the metal. The comparative study of the coordination shift and the ^{31}P-^{13}C coupling constant reveals that two carbonyl groups trans to one of two phosphorus atoms in the diphosphine ligand are shifted toward the lower magnetic field more …
Chemical Constituents Of Centaurea Cuneifolia, Ümi̇t Aslan, Sevi̇l Öksüz
Chemical Constituents Of Centaurea Cuneifolia, Ümi̇t Aslan, Sevi̇l Öksüz
Turkish Journal of Chemistry
The whole plant material fo Centaurea cuneifolia Sm. afforded three sesquiterpene lactones; cnicin (1), dehydromelitensin (2) and dehydromelitensin-8-[(2^{'}-\alpha-hydroxy-\beta- hydroxyethyl)-acryloyl)] (3), the lignan; (-)-arctigenin (4), flavonoids; salvigenin (5), eupatilin (6), jaceosidin (7), acacetin (8), kaemferol (9), 5,7,4^{'}-trihydroxy-3-methylether (10), 5-hydroxy-3^{'},^{'},6,7-tetramethoxyflavone (11) and 5-hydroxy-3^{'},4^{'},7,8-tetramet hoxyflavone (12), a triterpene; \alpha-amyrin and a sterol; \beta-sitosterol. The structures of the isolates were determined by IR, UV, ^1H and ^{13}C NMR and MS spectroscopy.
Effects Of Ozonation On Cod Elimination Of Substituted Aromatic Compounds In Aqueus Solution, Şermi̇n Gül, Osman Seri̇ndağ, Hami̇t Boztepe
Effects Of Ozonation On Cod Elimination Of Substituted Aromatic Compounds In Aqueus Solution, Şermi̇n Gül, Osman Seri̇ndağ, Hami̇t Boztepe
Turkish Journal of Chemistry
The chemical oxygen demand (COD) change of various substituted aromatic compounds, namely benzoic acid, p-aminobenzoic acid, p-toluenesulfonic acid, sulfanilic acid, nitro benzene, resorcinol, p-cresol, o- cresol, o-toluidine, aniline and 8-hydroxyquinoline were investigated at ozone doses of 5, 10, 15 and 20 mg O_{3}\cdotmin^{-1}, respectively. Percent COD removal of initial compounds after ozonation was compared with reported biodegradation results. The pH change and percent removal of selected compounds were also evaluated in ozone does of 20 mg O_{3}\cdotmin^{-1} up to 80 min. ozonation. The results showed that high ozone doses are needed to obtain better elimination of initial compounds and also …
An Efficient Acetylation Of Primary And Secondary Aliphatic Alcohols With Acetic Anhydride In The Presence Of Graphite Bisulphate, Hasan Seçen, A. Hami̇t Kalpar
An Efficient Acetylation Of Primary And Secondary Aliphatic Alcohols With Acetic Anhydride In The Presence Of Graphite Bisulphate, Hasan Seçen, A. Hami̇t Kalpar
Turkish Journal of Chemistry
In cyclohexane, thirteen examples of primary and secondary aliphatic alcohols were easily converted to the corresponding acetate derivatives within a short time, ranging from 5 min to 2.5 h, and in good yields close to 90%, using acetic anhydride as reagent and graphite bisulphate as an efficient catalyst.
Thermodynamics Of The Dissociation Of Chromium Soap Solutions In Benzene-Dimethyl Formamide, Hüseyi̇n Topallar, Yüksel Bayrak
Thermodynamics Of The Dissociation Of Chromium Soap Solutions In Benzene-Dimethyl Formamide, Hüseyi̇n Topallar, Yüksel Bayrak
Turkish Journal of Chemistry
Critical micelle concentrations and dissociation constants for chromium soaps (myristate, palmitate and stearate) in a mixture of benzene and dimethyl formamide (7:3, vol/vol) were determined by means of conductivity measurements. These soaps behave as simple moderate electrolytes in dilute solutions. Critical micelle concentrations and dissociation constants decreased with increasing numbers of carbon atoms in the soap molecules. Thermodynamic parameters such as heat of dissociation, \DeltaH_d, change in free energy, \DeltaG_d, and entropy, \DeltaS_d, per mole for the dissociation process were also evaluated.
The Effect Of Phosphate Ions (Po^{3-}_4) On The Corrosion Of Iron In Sulphat Solutions, Günay Kilinççeker, B. Yazici, M. Erbi̇l, H. Gali̇p
The Effect Of Phosphate Ions (Po^{3-}_4) On The Corrosion Of Iron In Sulphat Solutions, Günay Kilinççeker, B. Yazici, M. Erbi̇l, H. Gali̇p
Turkish Journal of Chemistry
The effect of phosphate ions on the corrosion of iron in sulphate solutions at different temperatures (293 K, 313 K, 333 K and 353 K) and at different pH (pH=2.1, 7.2 and 12.3) values was investigated. The electrochemical three-electrode technique was employed. The cathodic and anodic current-potential curves were obtained by strating from the corrosion potential measured against SCE and polarizing it first in cathodic and then in anodic direction. The results obtained indicate that at high pH (pH=7.2 and 12.3) SO^{2-}_{4}+PO^{3-}_{4}ions together reduce the corrosion rate of iron to a greater extent than SO^{2-}_{4} alone. At low pH (pH=2.1), …
The Role Of Electrolytically Co-Deposited Platinum-Palladium Electrodes On The Electrooxidation Of D. Glucose In Alkaline Medium: A Synergistic Effect, İpek Beceri̇k
Turkish Journal of Chemistry
The electrooxidation of D. glucose was investigated on platinum-palladium alloy electrodes of different compositions in alkaline aqueous solutions. The surface characteristics of the alloys in contact with electrolytic solution were studied using cyclic voltammetry. In particular, a surface enrichment in platinum due to a preferential dissolution of palladium was shown. Enhanced electrocatalytic activity at about 37 at. % in Pd was obtained when compared to pure metals, thus leading to a synergistic effect. The electrocatalytic activity of different alloys for D. glucose oxidation has been chacterized by exchange current densities obtained from extrapolation of Tafel lines to calculated equilibrium potential. …
Synthesis And Spectral Characterisation Of Novel Azo-Azomethine Dyes, Hati̇ce Karaer, İsmai̇l E. Gümrükçüoğlu
Synthesis And Spectral Characterisation Of Novel Azo-Azomethine Dyes, Hati̇ce Karaer, İsmai̇l E. Gümrükçüoğlu
Turkish Journal of Chemistry
The synthesis of novel azo-azomethine dye derivatives of substituted Schiff bases were carried out by the reaction of substituted 1-naphtylamine with 4-nitro and 2-chloro benzenediazonium tetraflouroborate salts as a coupling component. These compounds were identified by IR, UV-Vis and ^1H-NMR spectroscopic techniques, and elemental analysis.
Electrooxidation Of Linear Alkyl Benzene Sulfonate (Las) On Pt Electrodes, Bi̇rgül Yazici, Si̇bel Zor
Electrooxidation Of Linear Alkyl Benzene Sulfonate (Las) On Pt Electrodes, Bi̇rgül Yazici, Si̇bel Zor
Turkish Journal of Chemistry
The electrochemical behaviour of linear alklybenzene sulfonate (LAS) on Pt electrodes was investigated in 0.05M Na_2SO_4 and in 0.1M NaCl at pH=8 by the potentiokinetic method and by electrolysis. The anodic and cathodic semilogarithmic current-potential curves were obtained between -1.6V - +1.6V. The experimental discharge potentials were determined by means of current-potential-curves obtained by electrolysis between 0-3V. The percentages of surface active material remaining in the solution after specified periods (0-6hrs) were determined for different initial concentrations of LAS (30, 150, 300 ppm) by using a potentiostat at +1.6V and by applying a potential of 20V via a direct current …
The Application Of A Scanning Electron Microscope With An Energy Dispersive X-Ray Analyser (Sem/Edxa) For Gunshot Residue Determination On Hands For Some Cartridges Commonly Used In Turkey, Kezban Gökdemi̇r, Ertan Seven, Yüksel Sarikaya
The Application Of A Scanning Electron Microscope With An Energy Dispersive X-Ray Analyser (Sem/Edxa) For Gunshot Residue Determination On Hands For Some Cartridges Commonly Used In Turkey, Kezban Gökdemi̇r, Ertan Seven, Yüksel Sarikaya
Turkish Journal of Chemistry
The primers of the 10 commonly used cartridges in Turkey, MKE MP5, GECO Luger, FC Luger, WIN Luger, S&B Luger, WRA Luger, FNB Luger, P Luger, KF 80 Luger and SINTOX ACTION Luger were first examined with a SEM/EDXA. Then these cartridges used in test firings and the GSR on the hands of the test shooters was collected using adhesive-coated sample stubs and examined with a SEM/EDXA. Samples were scanned by viewing the BSE (Backscattered electron) image and, brighter and spherical particles were located, and then analysed with an EDXA. The elemental compositions of the GSR of the studied cartridges …
Nepetalactones And Other Constituents Of Nepeta Nuda Ssp. Albiflora, Gamze Kökdi̇l, Sabi̇ha M. Yalçin, Gülaçti Topçu
Nepetalactones And Other Constituents Of Nepeta Nuda Ssp. Albiflora, Gamze Kökdi̇l, Sabi̇ha M. Yalçin, Gülaçti Topçu
Turkish Journal of Chemistry
The hexane extract of Nepeta nuda ssp. albiflora led to the isolation of six known monoterpene nepetalactones, 4a\alpha,7\alpha,7a\alpha-nepetalactone (1), 4a\alpha,7\alpha,7a\beta-nepetalactone (2), 4a\beta,7\alpha,7a\beta-nepetalactone (3), 4a\beta,7\alpha,7a\alpha-nepetalactone (4), 4a\alpha,7\beta,7a\beta-nepetalactone (5), 3\alpha-hydroxy-4a\alpha,7\alpha,7a\alpha-dihydron\-epe\-tal\-actone (=nepetalic acid) (6) and a dimeric 5,9-dehydronepetalactone (7) along with two known steroids \beta-sitosterol and sitosterol 3-one and a triterpene betulinic acid. The acetone extract of the same plant afforded compound 7 in a higher yield in addition to compounds 2 and 6, and sesquiterpene caryophyllene oxide, the iridoid glucoside 1,5,9-epideoxyloganic acid, the triterpenoids oleanolic, ursolic and betulinic acids, and sitosterol 3\beta-glucoside.
Nonyl-And Dodecylamines Intercalated Bentonite And Illite From Turkey, Gülten Akçay, M. Kadi̇r Yurdakoç
Nonyl-And Dodecylamines Intercalated Bentonite And Illite From Turkey, Gülten Akçay, M. Kadi̇r Yurdakoç
Turkish Journal of Chemistry
Bentonite and illite were interacted with nonyl- and dodecylammonium salt solutions to see how the alkylammonium ions became attached and oriented within the interlamellar space of the clays. X-ray diffraction analyses were carried out to obtain information on the interlamellar organization and orientation of the adsorbed alkylammonium compounds. Thermogravimetric analysis (TG, DTG) and Fourier Transform Infrared Analyses (FTIR) were performed to characterize the samples and to determine the amounts adsorbed by the clay samples. The modification process was effective in nonyl- and dodecylammonium bentonites. Alkylammonium ions were adsorbed in the interlamellar space of the clays. Regarding the orientation of the …
Transition Metal Compound Mediated Reduction Of \Alpha-Amino Acids To 1,2-Amino Alcohols With Nabh_4 In Water, Ayhan S. Demi̇r, İdris M. Akhmedov, Özge Şeşenoğlu
Transition Metal Compound Mediated Reduction Of \Alpha-Amino Acids To 1,2-Amino Alcohols With Nabh_4 In Water, Ayhan S. Demi̇r, İdris M. Akhmedov, Özge Şeşenoğlu
Turkish Journal of Chemistry
A new efficient and cost-effective method for the preparation of 1,2-amino alcohols is described. The reactions of amino acids with NaBH_4 in the presence of NiCl_2 or MoO_3 in water give 1,2-amino alcohols in high yield. When optically pure amino acids were used, optically pure 1,2-amino alcohols were obtained.
Synthesis And Properties Of The Phthalocyanines Containing Eugenol (4-Allyl-2-Methoxyphenol), Erbi̇l Ağar, Selami̇ Şaşmaz, Ayşen Ağar
Synthesis And Properties Of The Phthalocyanines Containing Eugenol (4-Allyl-2-Methoxyphenol), Erbi̇l Ağar, Selami̇ Şaşmaz, Ayşen Ağar
Turkish Journal of Chemistry
New metal-free and metallophthalocyanines (M=Cu(II), Ni(II), Co(II), Zn(II) and Fe(II)) substituted with eugenol (4-allyl-2-methoxyphenol) from 1,2-dicyano-4-nitrobenzen are described. Cyclotetramerization of the substituted phthalonitrile leads to a product very soluble in common organic solvents. The characterization of the compounds was accomplished by elemental analysis, ^1H NMR, ^{13}C NMR, IR and UV-VIS spectral data.