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111.
Sylwia Studzińska Sandra Mounicou Joanna Szpunar Ryszard Łobiński Bogusław Buszewski 《Analytica chimica acta》2015
This text presents a novel method for the separation and detection of phosphorothioate oligonucleotides with the use of ion pair ultra high performance liquid chromatography coupled with inductively coupled plasma mass spectrometry The research showed that hexafluoroisopropanol/triethylamine based mobile phases may be successfully used when liquid chromatography is coupled with such elemental detection. However, the concentration of both HFIP and TEA influences the final result. The lower concentration of HFIP, the lower the background in ICP-MS and the greater the sensitivity. The method applied for the analysis of serum samples was based on high resolution inductively coupled plasma mass spectrometry. Utilization of this method allows determination of fifty times lower quantity of phosphorothioate oligonucleotides than in the case of quadrupole mass analyzer. Monitoring of 31P may be used to quantify these compounds at the level of 80 μg L−1, while simultaneous determination of sulfur is very useful for qualitative analysis. Moreover, the results presented in this paper demonstrate the practical applicability of coupling LC with ICP-MS in determining phosphorothioate oligonucleotides and their metabolites in serum within 7 min with a very good sensitivity. The method was linear in the concentration range between 0.2 and 3 mg L−1. The limit of detection was in the range of 0.07 and 0.13 mg L−1. Accuracy varied with concentration, but was in the range of 3%. 相似文献
112.
Łukasz Sadowski 《Aequationes Mathematicae》2017,91(6):1001-1007
We provide two new characterizations of the Takagi function as the unique bounded solution of some systems of two functional equations. The results are independent of those obtained by Kairies (Wy? Szko? Ped Krakow Rocznik Nauk Dydakt Prace Mat 196:73–82, 1998), Kairies (Aequ Math 53:207–241, 1997), Kairies (Aequ Math 58:183–191, 1999) and Kairies et al. (Rad Mat 4:361–374, 1989; Errata, Rad Mat 5:179–180, 1989). 相似文献
113.
E. Wierzbicki Cz. Woźniak L. Łacińska 《Archive of Applied Mechanics (Ingenieur Archiv)》2005,74(9):618-628
Two problems will be studied in this contribution. First, we analyse some phenomena which take place in a laminated solid and are caused by a fluctuation of time-dependent boundary tractions. Second, we investigate the transient effect of initial displacement fluctuations on the behaviour of a laminate. To solve the above problems we propose a new macroscopic 3D model for investigations of initial-boundary value problems in elastodynamics of a laminated medium. 相似文献
114.
115.
Two ordinary green light-emitting diodes used as light emitter and detector coupled with simple voltmeter form a complete,
cost-effective prototype of a photometric hemoglobinometer. The device has been optimized for cuvette assays of total hemoglobin
(Hb) in diluted blood using three different chemical methods recommended for the needs of clinical analysis (namely Drabkin,
lauryl sulfate, and dithionite methods). The utility of developed device for real analytics has been validated by the assays
of total Hb content in human blood. The results of analysis are fully compatible with those obtained using clinically recommended
method and clinical analyzer. 相似文献
116.
Albrecht Ł Jiang H Jørgensen KA 《Angewandte Chemie (International ed. in English)》2011,50(37):8492-8509
Asymmetric organocatalysis has been successfully incorporated in many multistep one-pot sequences to provide simple access to structurally complex target molecules in a highly stereoselective fashion. The key feature behind this success is the ability of organocatalyzed reactions to proceed efficiently in the presence of large amounts of spectator reagents. Additionally, owing to their organic nature and substoichiometric presence, organocatalysts are also expected to become innocent bystanders in subsequent transformations. In this Minireview, an easy-to-use classification and nomenclatural system that is capable of systematically and informatively describing each one-pot reaction is introduced, and selected important contributions within the field of organocatalytic one-pot reactions are reviewed according to this new system. Finally, future developments and perspectives in the field are discussed. 相似文献
117.
Dr. Iwona Olejniczak Dr. Andrzej Łapiński Prof. Roman Świetlik Dr. Jean Olivier Dr. Stéphane Golhen Dr. Lahcène Ouahab 《Chemphyschem》2011,12(11):2124-2130
The room‐temperature infrared and Raman spectra of a series of four isostructural polymeric salts of 2,3,6,7‐tetrakis(2‐cyanoethylthio)‐tetrathiafulvalene (TCE‐TTF) with paramagnetic (CoII, MnII) and diamagnetic (ZnII, CdII) ions, together with BF4? or ClO4? anions are reported. Infrared and Raman‐active modes are identified and assigned based on theoretical calculations for neutral and ionized TCE‐TTF using density functional theory (DFT) methods. It is confirmed that the TCE‐TTF molecules in all the materials investigated are fully ionized and interact in the crystal structure through cyanoethylthio groups. The vibrational modes related to the C?C stretching vibrations of TCE‐TTF are analyzed assuming the occurrence of electron–molecular vibration coupling (EMV). The presence of the antisymmetric C?C dimeric mode provides evidence that charge transfer takes place between TCE‐TTF molecules belonging to neighboring polymeric networks. 相似文献
118.
Łukasz Kosiński 《Journal of Geometric Analysis》2011,21(4):902-919
We give a characterization of non-hyperbolic pseudoconvex Reinhardt domains in ℂ2 for which the answer to the Serre problem is positive. Moreover, all non-hyperbolic pseudoconvex Reinhardt domains in ℂ2 with non-compact automorphism group are explicitly described. 相似文献
119.
Martowicz Adam Kantor Sławomir Pieczonka Łukasz Bryła Jakub Roemer Jakub 《Meccanica》2021,56(4):841-854
Meccanica - The work is devoted to the numerical aspects of the modeling tool elaborated to simulate the phenomenon of solid phase transformation in shape memory alloys. Particularly, a nonlocal... 相似文献
120.
KATARZYNA BUCIOR ANDRZEJ PATRYKIEJEW OREST PIZIO STEFAN SOKOŁOWSKI ZOFIA SOKOŁOWSKA 《Molecular physics》2013,111(6):721-731
We investigate the fluid—fluid demixing transitions in the case of adsorption of so-called symmetric binary mixtures in slit-like pores at temperatures higher than the bulk gas—liquid critical temperature. The aim of the study is to determine how the demixing of such mixtures in the pores depends on the bulk phase composition and on the parameters characterizing the pore. The calculations have been carried out by means of a density functional theory. In the case of an equimolar bulk mixture, the demixing transition inside the pore occurs only when the adsorption potentials of both species are identical. The occurrence of this transition is manifested by a cusp in the adsorption isotherm. For nonequimolar bulk phase compositions, the transition can also take place if the adsorption energies of both components are different. However, the difference in the adsorption energies should be small enough, otherwise a continuous demixing takes place. For non-equimolar compositions two branches of the grand canonical potential intersect, whereas for equimolar bulk composition they meet tangentially. We have determined phase behaviour for several model systems. 相似文献