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41.
Nina Bergman Denys Shevchenko Jonas Bergquist 《Analytical and bioanalytical chemistry》2014,406(1):49-61
This review summarizes various approaches for the analysis of low molecular weight (LMW) compounds by different laser desorption/ionization mass spectrometry techniques (LDI-MS). It is common to use an agent to assist the ionization, and small molecules are normally difficult to analyze by, e.g., matrix assisted laser desorption/ionization mass spectrometry (MALDI-MS) using the common matrices available today, because the latter are generally small organic compounds themselves. This often results in severe suppression of analyte peaks, or interference of the matrix and analyte signals in the low mass region. However, intrinsic properties of several LDI techniques such as high sensitivity, low sample consumption, high tolerance towards salts and solid particles, and rapid analysis have stimulated scientists to develop methods to circumvent matrix-related issues in the analysis of LMW molecules. Recent developments within this field as well as historical considerations and future prospects are presented in this review. 相似文献
42.
Dvornikova I. A. Buravlev E. V. Shevchenko O. G. Chukicheva I. Yu. Kutchin A. V. 《Russian Chemical Bulletin》2021,70(11):2185-2188
Some new derivatives based on 2,6-diisobornylphenol and containing amine moieties of the pinane structure at the para-position relative to the phenolic hydroxy group were synthesized. The antioxidant properties of the obtained compounds were estimated using various in vitro models. The introduction of diamine moiety into a starting molecule led to a significant increase in the radical scavenging activity and the ability to chelate Fe2+ ions.
相似文献43.
Byelikov A Adachi T Fujita H Fujita K Fujita Y Hatanaka K Heger A Kalmykov Y Kawase K Langanke K Martínez-Pinedo G Nakanishi K von Neumann-Cosel P Neveling R Richter A Sakamoto N Sakemi Y Shevchenko A Shimbara Y Shimizu Y Smit FD Tameshige Y Tamii A Woosley SE Yosoi M 《Physical review letters》2007,98(8):082501
The Gamow-Teller strength distributions below the particle threshold in 138La and 180Ta, deduced from high-resolution measurements of the (3He,t) reaction at 0 degrees, allow us to evaluate the role of charged-current reactions for the production of these extremely rare nuclides in neutrino-nucleosynthesis models. The analysis suggests that essentially all 138La in the Universe can be made that way. Neutrino nucleosynthesis also contributes significantly to the abundance of 180Ta but the magnitude depends on the unknown branching ratio for population of the long-lived isomer. 相似文献
44.
V. E. Shishkin E. V. Mednikov Yu. V. Popov M. A. Shevchenko O. V. Anishchenko E. V. Gurba 《Russian Journal of General Chemistry》2014,84(6):1130-1132
Reactions of sodium derivatives of C-phosphorylated acetamidines with benzenesulfonyl chloride were studied. The reactions proceed selectively to form benzenesulfonyl-containing acetamidine derivatives. A convenient method for the synthesis of a new type of C-phosphorylated acetamidines was developed utilizing CH-acid properties. 相似文献
45.
Kuznetsov N. M. Shevchenko V. G. Belousov S. I. Chvalun S. N. 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2020,94(2):376-381
Russian Journal of Physical Chemistry A - The frequency dependences of electrical conductivity with both real and imaginary components of a dielectric permittivity of polydimethylsiloxane oil... 相似文献
46.
47.
V. A. Beloshenko V. N. Varyukhin V. Yu. Dmitrenko Yu. I. Nepochatykh V. Z. Spuskanyuk A. N. Cherkasov B. A. Shevchenko 《Technical Physics》2009,54(12):1790-1794
The structure and magnetic properties of Cu-Fe fiber composites prepared by packet hydrostatic extrusion are studied. The
number of armco-iron fibers in the copper matrix attained n ∼ 8 × 1010, and rated diameter d of fibers varied from 2 mm to 3 nm. A correlation is observed between the magnetization hysteresis curves and low-frequency
magnetic susceptibility obtained on samples with various values of d. It is shown that the magnetic properties of composites in the submicrometer range of d values are satisfactorily described in the magnetization reversal theory for small ferromagnetic particles. 相似文献
48.
49.
Vladimir Ya Shevchenko 《Structural chemistry》2012,23(4):943-944
There is a special collection of contribution in the August 2012 issue of Structural Chemistry honoring the Swedish crystallographer Sten Andersson. This Encomium emphasizes the exemplary characteristics of his oeuvre. 相似文献
50.