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31.
P. A. Loboda V. A. Lykov V. Yu. Politov J. Nilsen 《Applied physics. B, Lasers and optics》1993,57(5):325-329
We propose using the Ti XXI He- emission line to resonantly photo-pump Li-like Mo (Z=42) and produce lasing on several n=5 n=4 transitions near 24 Å. The continuum emission from Ti photoionizes the Mo to the Li-like isoelectronic sequence. Gains of 1–2 cm–1 are calculated on these lines before the inclusion of Stark broadening which lowers the gain by as much as a factor of two. 相似文献
32.
The energy levels of 123I and 125I have been studied in the 122, 124Te(3He, d)123, 125I reactions at 24 MeV bombarding energy. The reaction products were analysed with an Enge split-pole magnetic spectrograph. A total of 57 levels below 3.3 MeV in 123I and 79 levels below 4.1 MeV in 125I were observed. Angular distributions were measured and compared with DWBA calculations to obtain orbital angular momentum transfers and spectroscopic strengths. The results were compared to previous radioactive decay studies and to theoretical energy level calculations. 相似文献
33.
Véronique Morisson-Iveson Harry Wadsworth Joanna Passmore Amanda Ewan Sondre Nilsen Mikkel Thaning William Trigg 《Tetrahedron letters》2014
[18F]GE-180 has been demonstrated to be a promising new positron emission tomography radiotracer for targeting translocator protein. PET imaging of TSPO will enable measurement of neuroinflammation and microglia activity in vivo. The synthetic route used in the initial discovery of GE-180, whilst enabling the rapid evaluation of the structure–activity relationships (SAR) in this molecular class, was not high yielding and not suitable for scale-up. Here we present an optimised route towards GE-180 and the radiolabelling precursor of [18F]GE-180 with significantly improved yields due to a strategy which improves the regioselectivity of the key indole formation step of the synthesis. 相似文献
34.
Per Arild Kjølseth Andresen Xiaoli Yang Johan Sjöblom Harald Linga Finn P. Nilsen 《Journal of Dispersion Science and Technology》2013,34(1-2):187-196
The droplet size distribution (DSD) of unstable water/oil dispersions has been studied with a new technique. The technique is based on a fast dilution of the dispersion injected into an analysis vessel where the DSD is analyzed with a video camera and a image analyzing tool. Dispersions generated with no pressure drop in the flow rig were compared to those generated with a pressure drop over a needle valve. The latter dispersion showed a much narrower DSD and a lower average droplet diameter. The results are from preliminary experiments in order to evaluate the method. 相似文献
35.
Kleivdal H Kristiansen SI Nilsen MV Goksøyr A Briggs L Holland P McNabb P 《Journal of AOAC International》2007,90(4):1011-1027
A collaborative study was conducted on the Biosense amnesic shellfish poisoning (ASP) enzyme-linked immunosorbent assay (ELISA) for the determination of domoic acid (DA) toxins in shellfish in order to obtain interlaboratory validation data for the method. In addition, a method comparison study was performed to evaluate the ASP ELISA as an alternative to the current liquid chromatography (LC) reference method for DA determination. The study material comprised 16 shellfish samples, including blue mussels, Pacific oysters, and king scallops, spiked with contaminated mussel homogenates to contain 0.1-20 mg DA/kg shellfish flesh. The shellfish samples were extracted with 50% aqueous methanol, and the supernatants were directly analyzed. Sixteen participating laboratories in 10 countries reported data from the ASP ELISA, and 4 of these laboratories also reported data from instrumental LC analysis. The participating laboratories achieved interlaboratory precision estimates for the 8 Youden paired shellfish samples in the range of 10-20% for RSD(r) (mean 14.8 +/- 4%), and 13-29% for RSDR (mean 22.7 +/- 6%). The precision estimates for the ELISA data did not show a strong dependence on the DA concentration in the study samples, and the overall precision achieved was within the acceptable range of the Horwitz guideline with HorRat values ranging from 1.1 to 2.4 (mean HorRat 1.7 +/- 0.5). The analysis of shellfish samples spiked with certified reference material (CRM)-ASP-MUS-b gave recoveries in the range of 88-122%, with an average recovery of 104 +/- 10%. The estimate on method accuracy was supported by a correlation slope of 1.015 (R2 = 0.992) for the determined versus the expected DA values. Furthermore, the correlation of the ASP ELISA results with those for the instrumental LC analyses of the same sample extracts gave a correlation slope of 1.29 (R2 = 0.984). This indicates some overestimation of DA levels in shellfish by the ELISA, but it is also a result of apparent low recoveries for the LC methods. This interlaboratory study demonstrates that the ASP ELISA is suitable for the routine determination and monitoring of DA toxins in shellfish, and that it offers a rapid and cost-effective methodology with high sample throughput. 相似文献
36.
Schmidt F Strozynski M Salus SS Nilsen H Thiede B 《Rapid communications in mass spectrometry : RCM》2007,21(23):3919-3926
Stable isotope labeling with amino acids in cell culture (SILAC) has evolved to be a major technique for quantitative proteomics using cell cultures. We developed a rapid method to follow and determine the incorporation of arginine and lysine. Analysis of the heavy state is required to avoid quantification errors. Moreover, the mixture of light and heavy states can be exploited to normalize the protein amount for subsequent relative quantification experiments. Therefore, peptides from different cell lines were extracted with 0.1% trifluoroacetic acid and analyzed by matrix-assisted laser desorption/ionization tandem time-of-flight (MALDI-TOF/TOF) mass spectrometry (MS). This analysis was highly reproducible and was performed in less than 2 h, significantly faster than other methods for the same purpose. Similar peptide mass profiles were obtained for human EBV-transformed B, Jurkat T, and HeLa cells as well as for mouse embryonic fibroblasts. Proteolytic fragments of 27 human proteins were identified with 56 peptides by MALDI-MS/MS and can be used as a database for these kinds of experiments. Sequencing revealed that the peptides were predominantly amino- and carboxy-terminal protein fragments displaying a specificity characteristic of the acidic proteases cathepsin D and E. Many of the identified peptides contained arginine and/or lysine, allowing determination of the incorporation rate of these amino acids. Furthermore, the rate of conversion of arginine into proline could be monitored easily. 相似文献
37.
A thermopile has been constructed for detecting heat of reaction during the individual steps taking place in the growth cycles
of atomic layer deposition (ALD). The thermopile sensor consists of 64 junctions of thermocouple type K. It has successfully
been applied to characterize ALD growth of Al2O3 from Al(CH3)3 (TMA) and H2O, and has furthermore been applied to explore energetics of ALD growth for the following combinations of precursors: TMA + O3, TMA + O2, TMA + hydroquinone, TiCl4 + H2O, and Zn(CH3CH2)2 + H2O. The thermopile clearly identifies exo/endothermal reaction steps, the effect of surface temperature on exposure to precursors
from cold sources as well as variation in the flow of gases, and allows setting up of experiments where variations in precursors
and pulsing parameters may provide mechanistic insight into the ALD growth. The sensor represents a new and complementary
tool for in situ characterization of thin film growth by ALD. 相似文献
38.
Ritucci A Tomassetti G Reale A Arrizza L Zuppella P Reale L Palladino L Flora F Bonfigli F Faenov A Pikuz T Kaiser J Nilsen J Jankowski AF 《Optics letters》2006,31(1):68-70
We applied a 0.3 mJ, 1.7 ns, 46.9 nm soft-x-ray argon laser to ablate the surface of large bandgap dielectrics: CaF2 and LiF crystals. We studied the ablation versus the fluence of the soft-x-ray beam, varying the fluence in the range 0.05-3 J/cm2. Ablation thresholds of 0.06 and 0.1 J/cm2 and ablation depths of 14 and 20 nm were found for CaF2 and LiF, respectively. These results define new ablation conditions for these large bandgap dielectrics that can be of interest for the fine processing of these materials. 相似文献
39.
DC magnetization, neutron depolarization and neutron diffraction (with both polarized and unpolarized neutrons) measurements
have been reported for the Co1.1−x
Zn
x
Ge0.1Fe1.2O1 spinels with x=0.5, 0.6 and 0.7. Neutron depolarization and neutron diffraction measurements confirm the presence of a long range ferrimagnetic
ordering of the local canted spins in these ferrite samples. The observed features of low field magnetization have been explained
under the framework of thermally activated domain wall movement of ferrimagnetic arrangement of local canted spins. An important
role of magnetic anisotropy (due to the presence of Co2+ ions) in establishing the magnetic ordering and domain kinetics in these ferrites has been observed. 相似文献
40.
A holographic interferometer senses vapor-induced optical path length changes in polymer or other chemically sensitive films. The interferometer is inherently sensitive to changes in chemical vapor content, self-compensates for drifts, and accommodates a large array of sensor elements. A sniff-locked-loop synchronous detection method takes advantage of the interferometer's rapid response to achieve vapor concentration sensitivity in the parts-per-billion (ppb, parts in 10(9)) range. We demonstrate, for example, 40 ppb sensitivity to ethyl alcohol using poly(N-vinyl pyrrolidone) with a measurement time of 5 s. 相似文献