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101.
Establishment of the frequency of analysis for discontinuous measurements in process control.Application of sampling theory to industrial chemical processes involves special problems arising from the peculiarities of the processes and of the analytical work. Apart from in the process itself, it is necessary to consider the statistical error of the correlation function caused by the finite length of the observed signal. Knowledge of the correlation time of the stochastic signal makes it possible to estimate the optimal time-difference between two analyses, depending on the variance of the process and the allowed analytical tolerance. 相似文献
102.
Brundermann E Bergner A Petrat F Schiwon R Wollny G Kopf I De Groot H Havenith M 《The Analyst》2004,129(10):893-896
We have set up a near-infrared microscope using a tuneable diode laser in the range from 1530 to 1570 nm. This spectral range is close to the peak of the water overtone absorption. We used this new microscope to study liver cells, hepatocytes, showing that quantitative information of the intracellular water concentration in living cells can be extracted. 相似文献
103.
Kowalski P Chmielewska A Konieczna L Oledzka I Zarzycki PK Lamparczyk H 《Biomedical chromatography : BMC》2004,18(5):311-317
A simple and robust analytical method for rapid separation and sensitive quantification of baclofen in human plasma by capillary electrophoresis technique was developed. Electrophoretic separation was optimized and successfully performed using simple sodium tetraborate aqueous solution. Observed detection limit in biological material was 10 ng. Using UV detection at 200 nm excellent linearity (r = 0.999) was observed over the concentration range from 0.025 to 1.0 microg mL(-1). The described method has been validated and applied to the quantitative determination of baclofen in human plasma. The bioavailability of Baclofen (Polpharma) and Lioresal (Novartis) in 18 healthy volunteers was investigated. The results indicate bioequivalence of the reference and Baclofen preparations. 相似文献
104.
Alla Zablotskaya Izolda Segal Anatoly Mishnev Mikhail Maiorov Elmars Blums Irina Shestakova Ilona Domracheva 《应用有机金属化学》2013,27(12):716-722
Superparamagnetic iron oxide/oleic acid nanoparticles bearing lipid‐like organosilicon N‐(2‐hydroxyethyl)‐1,2,3,4‐tetrahydroisoquinoline derivatives have been synthesized with the aim of their potential biomedical application. X‐ray diffraction analysis, Dynamic light‐scattering measurements, method of magnetogranulometry and some others have been employed to investigate the morphology and properties of the nanoparticles synthesized. The magnetic core diameter of mixed covered nanoparticles ranged between 4.8 and 9.6 nm. The magnetization analyses showed that the particles are superparamagnetic at room temperature. In vitro cell cytotoxicity and intracellular NO generation caused by the water magnetic solution of nanoparticles possessing cytotoxic organosilicon heterocyclic choline analogue, namely N‐(2‐dimethyl‐n‐hexadecylsiloxyethyl)‐N‐methyl‐1,2,3,4‐tetrahydroisoquinolinium iodide, was examined in relation to monolayer human fibrosarcoma (HT‐1080) and mouse hepatoma (MG‐22A) tumour cell lines and normal mouse fibroblasts (NIH 3T3). The biological studies have revealed its selective cytotoxicity in tumour cells and strong effect on MG‐22A cell morphology. Incorporation of the synthesized nanoparticles into cells was observed. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
105.
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107.
Sepioł J Grabowska A Borowicz P Kijak M Broquier M Jouvet Ch Dedonder-Lardeux C Zehnacker-Rentien A 《The Journal of chemical physics》2011,135(3):034307
Excited-state intramolecular proton transfer (ESIPT) reaction has been studied in a molecule showing dual fluorescence, the 2,5-bis(2-benzoxazolyl)-4-methoxyphenol (BBMP), and its isotopomers, where the methoxy, and alternatively, the OH group has been deuterated. Attention is focused on the influence of electron donating OCH(3) substituent on fast excited state reaction. Comparison between the resonance-enhanced multiphoton ionization spectrum and the laser-induced excitation of the primary and phototautomeric emissions has been done. The geometry, electron density distribution, vibrational structure as well as the potential energy profiles in the S(0) and S(1) states of four possible rotameric forms of BBMP were calculated with application of the density functional theory (DFT). It allowed identifying the most probable conformer and assessing the role of low-frequency motions for the ESIPT efficiency. 相似文献
108.
Smriti Singh Ilona Zilkowski Andrea Ewald Tobias Maurell‐Lopez Krystyna Albrecht Martin Möller Jürgen Groll 《Macromolecular bioscience》2013,13(4):470-482
Nanogels consist of three dimensionally cross‐linked hydrophilic polymer chains and can thus be easily modified through functionalization of the polymeric building blocks, for example to yield stimuli‐sensitive materials. For drug transport and intracellular release, redox‐sensitive systems are especially of interest, as the intracellular space is reductive. In this study, parameters that allow preparation of nanogels with tunable size between 150 and 350 nm are systematically evaluated and identified. Most importantly, a new and mild oxidation catalyst, alloxan, is introduced for the preparation of the nanogels. This broadens the range of possible payloads to more‐sensitive molecules. Particle stability, degradation in cytosolic conditions, and cytocompatibility in concentrations up to 10 mg · mL?1 are demonstrated.
109.
Structural Chemistry - Increasing research interests have been paid to developing efficient multifunctional material systems (MFMS) by using various composite materials, owing to their useful... 相似文献
110.
Leite Irena Andrianov Victor Zelencova-Gopejenko Diana Loza Einars Kazhoka-Lapsa Iveta Domracheva Ilona Stoyak Marta Chlopicki Stefan Kalvins Ivars 《Chemistry of Heterocyclic Compounds》2021,57(11):1086-1106
Chemistry of Heterocyclic Compounds - Acyl derivatives of aziridine-2-carboxylic acid have been synthesized and tested as PDIA1 inhibitors. Calculations of charge value and distribution in... 相似文献