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21.
C. A. Rinaldi J. C. Ferrero S. I. Lane E. V. Oexler 《Journal of Chemical Sciences》1991,103(3):465-469
The IR multiphoton dissociation of CF3I has been studied in the presence of isobutane and with isobutane and Ar and CO2 as inert gases. The dependence of the reaction probability P(Φ) with fluence (ϕ) is confirmed. Modeling of the experimental results shows that for the energy transfer processes the average energy transferred
per collision 〈†E〉d varies with (ϕ). 相似文献
22.
Ciara Lane Martin Stynes John O'Donoghue 《International Journal of Mathematical Education in Science & Technology》2016,47(7):1009-1027
A questionnaire survey was carried out as part of a PhD research study to investigate the image of mathematics held by post-primary students in Ireland. The study focused on students in fifth year of post-primary education studying ordinary level mathematics for the Irish Leaving Certificate examination – the final examination for students in second-level or post-primary education. At the time this study was conducted, ordinary level mathematics students constituted approximately 72% of Leaving Certificate students. Students were aged between 15 and 18 years. A definition for ‘image of mathematics’ was adapted from Lim and Wilson, with image of mathematics hypothesized as comprising attitudes, beliefs, self-concept, motivation, emotions and past experiences of mathematics. A questionnaire was composed incorporating 84 fixed-response items chosen from eight pre-established scales by Aiken, Fennema and Sherman, Gourgey and Schoenfeld. This paper focuses on the findings from the questionnaire survey. Students’ images of mathematics are compared with regard to gender, type of post-primary school attended and prior mathematical achievement. 相似文献
23.
The preceding paper Strong statements of analysisby A. R. D. Mathias defends a so-called full-blooded set theorywithout full detail [3]. He again objects to a weak set theorywhich he calls Mac, in which the usual ZermeloFraenkelseparation scheme is required only for formulas with suitablyrestricted quantifiers. I had proposed that suchseparation is adequate for all standard uses of set theory inmathematics. But Mathias has not produced any counter examplesof actual mathematics which requires the use of a stronger separation. 相似文献
24.
Thin films of SnSb2S4 have been prepared on glass substrate by using thermal evaporation techniques. The films were annealed in argon gas at low pressure in sealed glass ampoules at 85 °C, 150 °C, 275 °C and 325 °C. XRD of the films reveal that the low temperature annealed films are poly crystalline while the as deposited films and high annealed films are in amorphous states. There is no adequate variation in the photoconductivity response of the amorphous and crystalline phases. The transmittance of the films is low and having no transmittance below 740 nm. The band gap calculated by ellipsometry technique is in the range of 1.82–3.1 eV. The films have n-type conductivity but the film annealed at 325 °C show p-type conductivity. 相似文献
25.
26.
A single fully automated generic microbore liquid chromatography electrospray time-of-flight protocol has been developed for the analysis of single beads, single beads with analytical constructs, and isotopically labelled dialkylamine hard tags. The protocol relies upon the incorporation of an isotopic signature into the linker and/or derivatising molecule to give a specific isotopic ratio together with an accurate isotopic difference. These properties facilitate highly specific and sensitive analysis of beads and hard tags using accurate isotopic difference analysis (AIDA) without prior knowledge of the molecular weight. Three open access methods with automated processing have been developed around a core generic approach. 相似文献
27.
Pattison LK Cullen DM Smith JF Fletcher AM Walker PM El-Masri HM Podolyák Z Wood RJ Scholey C Wheldon C Mukherjee G Balabanski D Djongolov M Dalsgaard T Thisgaard H Sletten G Kondev F Jenkins D Lane GJ Lee IY Macchiavelli AO Frauendorf S Almehed D 《Physical review letters》2003,91(18):182501
Evidence is presented for multiphonon excitations based on a high-spin (25 Planck) intrinsic state in the deformed nucleus 182 Os. Angular momentum generation by this mode competes with collective rotation. The experimental data are compared with tilted-axis cranking calculations, supporting the vibrational interpretation. However, the lower experimental energies provide evidence that more complex interactions of states are playing a role. 相似文献
28.
Trout AL Prasad R Coffin D DiMartini A Lane T Blessum C Khatter N Landers JP 《Electrophoresis》2000,21(12):2376-2383
Transferrin, an iron transport protein found in serum and cerebrospinal fluid, is known to be microheterogeneous with respect to its carbohydrate and sialic acid content. The forms of transferrin deficient in sialic acid and/or carbohydrate, termed carbohydrate-deficient transferrin (CDT), have been of clinical interest for almost two decades as a result of the initial finding that elevated CDT concentrations are associated with chronic, excessive alcohol abuse. We demonstrate the utility of capillary electrophoresis for examining the CDT sialoform profile via the direct electrophoresis of serum. The need for negligible preelectrophoresis sample preparation and absence of postelectrophoresis processing dramatically decreases analysis time compared to slab gel-based separations. Using a fluorocarbon-coated capillary containing a hydroxyethyl cellulose/borate buffer, the high resolution separation of serum components is effected in less than 30 min. Under these conditions, the beta region proteins (including transferrin) are well resolved from the alpha-2 and gamma zone proteins in a window where the individual transferrin sialoforms can be detected. The usefulness of this method is demonstrated with the electrophoresis of serum from subjects known to be either non-alcoholic and alcoholic. 相似文献
29.
Rower JE Bushman LR Hammond KP Kadam RS Aquilante CL 《Biomedical chromatography : BMC》2010,24(12):1300-1308
Gemfibrozil, a fibric acid hypolipidemic agent, is increasingly being used in clinical drug–drug interaction studies as an inhibitor of drug metabolizing enzymes and drug transporters. The validation of a fast, accurate and precise LC/MS method is described for the quantitative determination of gemfibrozil in an EDTA‐anticoagulated human plasma matrix. Briefly, gemfibrozil was extracted from human plasma by an acetonitrile protein precipitation method. The assay was reproducible with intra‐assay precision between 1.6 and 10.7%, and inter‐assay precision ranging from 4.4 to 7.8%. The assay also showed good accuracy, with intra‐assay concentrations within 85.6–108.7% of the expected value, and inter‐assay concentrations within 89.4–104.0% of the expected value. The linear concentration range was between 0.5 and 50 µg/mL with a lower limit of quantitation of 0.5 µg/mL when 125 µL of plasma were extracted. This LC/MS method yielded a quick, simple and reliable protocol for determining gemfibrozil concentrations in plasma and is applicable to clinical pharmacokinetic studies. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
30.
Sharpless KE Lindstrom RM Nelson BC Phinney KW Rimmer CA Sander LC Schantz MM Spatz RO Thomas JB Turk GC Wise SA Wood LJ Yen JH 《Journal of AOAC International》2010,93(4):1262-1274
Standard Reference Material (SRM) 1849 Infant/Adult Nutritional Formula has been issued by the National Institute of Standards and Technology (NIST) as a replacement for SRM 1846 Infant Formula, issued in 1996. Extraction characteristics of SRM 1846 have changed over time, as have NIST's analytical capabilities. While certified mass fraction values were provided for five constituents in SRM 1846 (four vitamins plus iodine), certified mass fraction values for 43 constituents are provided in SRM 1849 (fatty acids, elements, and vitamins) and reference mass fraction values are provided for an additional 43 constituents including amino acids and nucleotides, making it the most extensively characterized food-matrix SRM available from NIST. 相似文献