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11.
Supaporn Kradtap Hartwell Alison Kehling Somchai Lapanantnoppakhun 《Chromatographia》2014,77(13-14):883-891
The use of a small guard column (5-mm length) as a miniature analytical column in low-pressure liquid chromatography based on a sequential injection with lab-on-valve system was demonstrated. A strong initial mobile phase was used to rapidly deliver the sample zone to the column prior to simultaneous separation of analytes with weaker mobile phase. Separation of methyl-, ethyl-, propyl-, and butyl-4-hydroxybenzoates (MP, EP, PP, and BP) was achieved within about 120 s with sufficient peak resolution (all higher than 1.3) using 2,500 µL of mobile phase (composed of 1,087 µL of MeOH) per run. Detection limits were found to be 6.5, 8.0, 0.5, and 0.6 μmol L?1 for MP, EP, PP, and BP, respectively. The system was tested with common commercially available skin lotions and wet wipe products. The analysis results were in good agreement with those obtained from the high-performance liquid chromatography with a 10-cm-length packed column. 相似文献
12.
J. K. Hartwell P. L. Winston D. J. Marts L. D. Moore-McAteer S. C. Taylor 《Journal of Radioanalytical and Nuclear Chemistry》2005,264(1):127-132
Summary Some United States Department of Energy-owned spent fuel elements from foreign research reactors (FRRs) are presently being shipped from the reactor location to the US for storage at the Idaho National Engineering and Environmental Laboratory (INEEL). Two cadmium zinc telluride detector-based gamma-ray spectrometers have been developed to confirm the irradiation status of these fuels. One spectrometer is configured to operate underwater in the spent fuel pool of the shipping location, while the other is configured to interrogate elements on receipt in the dry transfer cell at the INEEL’s Interim Fuel Storage Facility (IFSF) Both units have been operationally tested at the INEEL. 相似文献
13.
Kornauth Wilh Bersch A. Philips Christ. Kob und Co. Donner Louise H. Weller C. Schweitzer Ch. L. Penny Ed. van Melckebeke H. J. Wheeler B. Hartwell Knorr W. Büttner Barthé W. Jerwitz C. F. Parker Gust Christ Ferdinand Kryz J. Katz H. Göckel R. Jabota J. J. L. von Rijn F. Baum Joseph Nerking A. E. Taylor J. Gadamer C. Th. L. Hagemann und C. A. Neufeld 《Fresenius' Journal of Analytical Chemistry》1902,41(11):686-695
Ohne Zusammenfassung 相似文献
14.
Kornauth Wilh Bersch A. Philips Donner Dr. Louise H. Weller C. Schweitzer Ch. L. Penny Ed. van Melckebeke H. J. Wheeler B. Hartwell Knorr W. Büttner Barthé W. Jerwitz C. F. Parker Gust Christ Ferdinand Kryz J. Katz H. Göckel R. Jabota J. J. L. von Rijn F. Baum Joseph Nerking A. E. Taylor J. Gadamer C. Th. L. Hagemann C. A. Neufeld Christ. Kob und Co. 《Analytical and bioanalytical chemistry》1902,41(11):686-695
15.
In this paper an alternative approach for measurement of στ product for 4
F
3/2→4
I
11/2 transition of Nd3+ doped YVO4 crystal is reported. In this method a microchip laser is formed by keeping a small piece of the sample in plane-plane resonator
and a diode laser (808 nm) is used for pumping. The pump power induced thermal lensing effect is used to make the cavity stable.
The cavity mode area is estimated by measuring the thermal lens focal length at the threshold and the average pump area is
measured by Gaussian fit to the intensity profiles of the pump beam. The value of στ product of Nd:YVO4 crystal obtained by this method is within 10% of the reported values. The advantage of this method is that it is a simple
method for direct measurement of στ product of laser crystals. 相似文献
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17.
Summary Gamma-ray spectrometry combined with acceptable knowledge (GSAK) is a technique for the characterization of certain remote-handled transuranic (RH-TRU) wastes. GSAK uses gamma-ray spectrometry to quantify a portion of the fission product inventory of RH-TRU wastes. These fission product results are then coupled with calculated inventories derived from acceptable process knowledge to characterize the radionuclide content of the assayed wastes. GSAK has been evaluated and tested through several test exercises. This paper describes these tests and their results; while the former paper in this issue presents the methodology, equipment and techniques. 相似文献
18.
Thalassemia involves gene mutation that causes the production of an insufficient amount of normal structure globin chains while Hb variant involves gene mutation that causes the change in type or number of amino acid of the globin chain. It has been reported that some 200 million people worldwide had hemoglobinopathies of some sort. Attempts to develop effective and economical techniques for screening and analysis of thalassemia and Hb variants have become very important. In this review, we report the different techniques available, ranging from initial screening to extensive analysis, comparing advantages and disadvantages. Some indirect studies related to thalassemia indication and treatment follow-up are also included. We hope that information on these various techniques would be useful for some scientists who are working on development of a new technique or improving the existing ones. 相似文献
19.
The dielectric relaxation phenomena of rigid polar liquid molecules chloral and ethyltrichloroacetate (j) in benzene, n-hexane and n-heptane (i) under 4.2, 9.8 and 24.6 GHz electric fields at 30°C are studied to show the possible existence of double relaxation times τ 2 and τ 1 for rotations of the whole and the flexible parts of molecules. The probability of showing double relaxation is more in aliphatic solvents indicating their nonrigidity. The symmetric and asymmetric distribution parameters γ and δ are obtained from X ij ′ /X 0ij and X ij ″ /X 0ij and w j →0 where X ij ′ and X ij ″ are real and imaginary parts of the complex orientational susceptibility X i * and X 0ij is the low frequency susceptibility which is real. X ij ’s are involved with the measured dielectric relative permittivities ε ij ′ , ε in ″ , ε 0ij and ε ∞ij of solutions. The theoretical weighted contributions c 1 and c 2 towards dielectric dispersions by Fröhlich’s method are compared with the experimental ones obtained from the graphical variation of X ij ′ /X 0ij and X ij ″ /X 0ij with weight fractions w j ’s at w j → 0. The measured dipole moments μ 2 and μ 1 of the whole and the flexible part of a polar molecule in terms of the linear coefficients β’s of X ij ′ ’s with w j ’s and the estimated τ 2 and τ 1 reveal their associations with aliphatic solvents. The theoretical dipole moments μ theo’s from the available bond angles and bond moments of the substituent polar groups of the molecules with the estimated μ’s suggest the mesomeric, inductive and electromeric effects in them under GHz electric field. 相似文献
20.