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Vladimír Vrkoslav Barbora Rumlov Timotej Strme Josef Cva
ka 《Journal of separation science》2020,43(13):2579-2588
A new capillary high‐performance liquid chromatography method with atmospheric pressure chemical ionization mass spectrometry was developed for the analysis of fatty acid methyl esters and long‐chain alcohols. The chromatographic separation was achieved using a Zorbax SB‐C18 HPLC column (0.3 × 150 mm, 3.5 μm) with a mobile phase composed of acetonitrile and formic acid and delivered isocratically at a flow rate of 10 μL/min. The column temperature was programmed simply, using a common column oven. Good reproducibility of the temperature profile and retention times were achieved. The temperature programming during the isocratic high‐performance liquid chromatography run had a similar effect as a solvent gradient; it reduced retention times of later eluting analytes and improved their detection limits. Two atmospheric pressure chemical ionization sources of the mass spectrometry detector were compared: an enclosed conventional ion source and an in‐house made ion source with a glass microchip nebulizer. The enclosed source provided better detectability of saturated fatty acid methyl esters and made it possible to determine the double bond positions using acetonitrile‐related adducts, while the open chip‐based source provided better analytical figures of merit for unsaturated fatty acid methyl esters. Temperature‐programmed capillary high‐performance liquid chromatography is a promising method for analyzing neutral lipids in lipidomics and other applications. 相似文献
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We present wavelength- and temperature-dependent refractive index equations for 5% MgO-doped congruent PPLN and for 1% MgO-doped
stoichiometric PPLN crystals valid for a wide spectral and temperature range. The dispersion equations were derived from quasi-phase-matched
nonlinear interactions with these two crystal compositions in the near and mid-infrared. The results show a good agreement
with previously published frequency conversion experiments.
PACS 42.65.Ky; 42.65.Yj; 42.70.Mp 相似文献
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Beyond eliminating the critical slowing down, multigrid algorithms can also eliminate the need to produce many independent fine-grid configurations for averaging out their statistical deviations, by averaging over the many samples produced in coarse grids during the multigrid cycle. Thermodynamic limits can be calculated to accuracy in justO(-2) computer operations. Examples described in detail and with results of numerical tests are the calculation of the susceptibility, the -susceptibility, and the average energy in Gaussian models, and also the determination of the susceptibility and the critical temperature in a two-dimensional Ising spin model. Extension to more advanced models is outlined. 相似文献
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Hribar Rok Hrga Timotej Papa Gregor Petelin Gašper Povh Janez Pržulj Nataša Vukašinović Vida 《Journal of Global Optimization》2022,82(2):283-312
Journal of Global Optimization - In this paper, we consider the symmetric multi-type non-negative matrix tri-factorization problem (SNMTF), which attempts to factorize several symmetric... 相似文献
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Smole Andreja Jagrič Timotej Bokal Drago 《Central European Journal of Operations Research》2021,29(3):791-808
Central European Journal of Operations Research - Our novel game-theoretic Principal/Two-Agent model ensures that the Principal has a reliable internal signal about the Agents’ invested work... 相似文献
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Matija Gatalo Marjan Bele Francisco Ruiz‐Zepeda Ervin est Martin ala Ana Rebeka Kamek Nik Maselj Timotej Galun Primo Jovanovi
Nejc Hodnik Miran Gaber
ek 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(38):13400-13404
Preparation of large quantities of high‐performance supported Pt‐alloy electrocatalysts is crucial for the faster development and implementation of low‐temperature proton exchange membrane fuel cells (PEMFCs). One of the prospective nanofabrication synthesis methods is based on the galvanic displacement (GD) reaction. A facile, highly reproducible, gram scale, water‐based double passivation GD method is now presented for the synthesis of carbon‐supported Pt‐M nanoparticles (M=Cu, Ni, Co). It offers great flexibility over the catalyst design, such as the choice of the sacrificial metal (M), variation of the chemical composition of alloy, variation of total metal loading (Pt+M) on carbon support, or even variation of the carbon support itself. The obtained Pt‐alloy catalysts are several times more active compared to a Pt reference and exhibits better stability during accelerated degradation tests performed at 60 °C. 相似文献
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The synthesis of 1-benzyl-2-methyl-5-methoxyindole-3-oxyacetic acid ( 11 ) and of 1-benzyl-2-methylindole-3-oxyacetic acid ( 17 ) was undertaken in the course of a study aimed at the preparation of potential anti-inflammatory agents. 相似文献