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1.
Mustafa Çelebier Ertan Şahin Nilgün Ancın Nurşen Altuntaş Öztaş Selma Gül Öztaş 《应用有机金属化学》2007,21(10):viii-viii
The article referenced above was first published online on 30 August 2007 with incorrect pagination; the pagination has now been corrected online and in print. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
2.
Summary The relative X-ray fluorescence (XRF) intensities for annular source and various annular specimen are measured with a Ge-Li
detection system and calculated by the Monte Carlo numerical techniques (MCNT).Kα X-ray intensities of annular specimens with different radii prepared from a pure-molybdenum foil are measured and it is
seen that the measured values are in good agreement with the values calculated by MCNT. The variation of the fluorescence
intensity due to the collimator radius is also studied. The differences between the MCNT and experimental results are discussed
in terms of the possible sources of errors. 相似文献
3.
4.
Y. Şahin R. Durak Y. Kurucu S. Erzeneoğlu 《Journal of Radioanalytical and Nuclear Chemistry》1994,177(2):403-413
Two analytical shape functions representing the shapes of - and characteristic X-ray photopeak sides obtained with a Ge(Li) detector are described. The photopeak centroid is accurately determined by using these functions. Energy dependence of photopeak tailing at the lower energy side of the photopeaks are obtained by the least-squares fitting method. The present method can be used for the analysis of partly overlapped photopeaks, one side of which is well resolved, with a sufficient accuracy. 相似文献
5.
A. Baştuğ Ö. Söğüt Y. Şahin M. Ertuğrul 《Journal of Radioanalytical and Nuclear Chemistry》2002,251(2):323-327
La and Lb X-ray fluorescence cross sections in Er, Ta, W and Au at excitation energies of 16.896, 22.581, 25.770, 32.890, 38.184, 43.949, 50.214 and 59.5 keV were investigated. Measurements were made using a low energy Si(Li) detector coupled to a model 4096 computerized multi-channel analyser. The experimental results were compared with the theoretically calculated values of L X-rays fluorescence cross sections and other experimental results. Good agreement was observed between experimental and theoretical values. 相似文献
6.
Ingeborg Csöregh Mátyás Czugler Anne Ertan Edwin Weber Jochen Ahrendt 《Journal of inclusion phenomena and macrocyclic chemistry》1990,8(3):275-287
The crystal structures of four dimethyl sulphoxide (DMSO) inclusion compounds with different carboxylic acid hosts,1–4, have been studied by single crystal X-ray analysis. Crystals of thetrans-9,10-dihydro-9,10-ethanoanthracene-11,12-dicarboxylic acid inclusion compound (1a), [1 · DMSO (1: 1)] show monoclinic (P21/n) symmetry with the unit cell dimensionsa = 11.522(4),b = 18.658(2),c = 8.709(1) Å and = 98.92(2)°. The clathrate of the 9,10-dihydro-9,10-ethanoanthracene-11,12-dicarboxylic acid (2a), [2 · DMSO (1: 2)] is triclinic (P) with the cell dimensionsa = 15.043(7),b =9.657(4),c = 8.118(7) Å, = 101.81(5), = 96.05(4) and = 100.04(4)°. Triclinic (P) symmetry is shown also by the inclusion compound of 9,10-dihydro-9,10-ethanoanthracene-11-monocarboxylic acid (3a) [3 · DMSO (1:1)] with the cell dimensionsa=6.3132(1),b=7.9846(2),c=17.5314(4) Å, = 96.46(2), = 87.08(2) and = 106.02(2)°. The 9,9-bianthryl-2-monocarboxylic acid clathrate (4a) [4 · DMSO (1:1)] is monoclinic (P21/n) and the cell dimensions area = 19.625(18),b = 8.817(1),c = 14.076(8) Å and = 97.92(6)°. In all these structures, the hosts show the same basic recognition pattern for the DMSO guest, involving a strong O-H ... O bond from the COON to the S=O group, and a possible C-H ... O type interaction between the carbonyl O atom of the host and a CH3 group of the guest. The crystals consist of discrete host-guest aggregates which are mainly held together by weak intermolecular interactions of the Van der Waals' type. The stoichiometries of the aggregates are, however, different. 相似文献
7.
8.
Seed oils of 12 Salvia species collected from different regions in Turkey (S. Albimaculata Hedge & Hub.-Mor., S. Candidisima Vahl., S. Cedronella Boiss., S. Cryptantha Montbret & Aucher ex Bentham, S. Forskahlei L., S. Fruticosa Miller (Sin. S. Triloba L. Fil), S. Halophila Hedge, S. Hypargeia Fisch. & Mey., S. Sclarea L., S. Tomentosa Miller, S. Tchihatcheffii (Fisch. & Mey.) Boiss., S. Virgata Jacq.) were obtained by Soxhlet apparatus using hexane. The oil yields were found to be between 2.0% and 20.9%. Fatty acids in the oils were converted to methyl esters and determined by GC/MS in methyl ester form. The main fatty acid components of S. halophila, S. Hypargeia, and S. Sclarea are unsaturated oleic, linoleic, and linolenic acids. In others except S. Candidissima, the dominant acids are oleic, linoleic and palmitic acids. 相似文献
9.
Chiral capillary electrophoresis: facts and fiction on the reproducibility of resolution with randomly substituted cyclodextrins 总被引:1,自引:0,他引:1
Comparative enantioseparation of the enantiomers of 1,1'-binaphthyl-2,2'-diyl hydrogen phosphate was performed with cyclodextrin (CD)-modified capillary electrophoresis (CE). Two single isomers, beta-CD, heptakis(2,3,6-tri-O-methyl)-beta-CD (TM-beta-CD), and heptakis(2,6-di-O-methyl)-beta-CD (DM-beta-CD) of 98% purity as well as heptakis(2,3-di-O-acetyl)-beta-CD were used and compared in terms of resolution power to randomly methylated and corresponding acetylated beta-CDs, which were synthesized in our laboratory. The methylated ones were characterized by means of matrix-assisted laser desorption/ionization-time of flight-(MALDI-TOF) mass spectrometry. By testing defined mixtures of single isomers and comparing their resolution power to randomly substituted CDs of similar degree of substitution we could show, that a simple characterization by the average molecular degree of substitution (DS) is not sufficient. In order to get reproducible results, a clearly defined substitution pattern is necessary, which is not given using randomly substituted CDs. Taken together, a validation of a chiral separation with "undefined" CD derivatives is almost impossible. 相似文献
10.
Karolina Kiebasa ahin Bayar Esin Apaydin Varol Joanna Srescek-Nazzal Monika Bosacka Piotr Midlicki Jarosaw Serafin Rafa J. Wrbel Beata Michalkiewicz 《Molecules (Basel, Switzerland)》2022,27(21)
Cost-effective activated carbons for CO2 adsorption were developed from molasses using H2SO4, H3PO4, HCl, NaOH, and KOH as activating agents. At the temperature of 0 °C and a pressure of 1 bar, CO2 adsorption equal to 5.18 mmol/g was achieved over activated carbon obtained by KOH activation. The excellent CO2 adsorption of M-KOH can be attributed to its high microporosity. However, activated carbon prepared using HCl showed quite high CO2 adsorption while having very low microporosity. The absence of acid species on the surface promotes CO2 adsorption over M-HCl. The pore size ranges that are important for CO2 adsorption at different temperatures were estimated. The higher the adsorption temperature, the more crucial smaller pores were. For 1 bar pressure and temperatures of 0, 10, 20, and 30 °C, the most important were pores equal and below: 0.733, 0.733, 0.679, and 0.536 nm, respectively. 相似文献