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1.
Crystallography Reports - Facets are formed at the periphery of the conical part of GaAs single crystals grown by the Czochralski method when the melt is supercooled at the crystal periphery. The... 相似文献
2.
Lyubimov S. E. Pavlova L. A. Sokolovskaya M. V. Korlyukov A. A. Davankov V. A. 《Russian Chemical Bulletin》2019,68(8):1599-1602
Russian Chemical Bulletin - The sorption of cadaverine from the air on hypercrosslinked polystyrene sorbents was investigated. An available technique for the introduction of iron oxide into the... 相似文献
3.
Natalia Shevchenko Galina Pankova Boris Shabsels Vadim Baigildin Alexander Khoshkin Timofei Ukleev 《Journal of Dispersion Science and Technology》2019,40(6):802-810
Monodisperse dye-containing crosslinked particles are promising for application in novel optical chemical sensors due to their intrinsic sensitivity. However, preparation of these particles in aqueous media still remains a challenge, since luminophores inhibit radical processes or else cannot embed into polymer chains because of difference in monomer reactivity ratios. In this work, novel dye-containing monodisperse crosslinked particles were prepared and characterized. In order to obtain dye-containing monodisperse crosslinked particles, we studied seed copolymerization of styrene in the presence of divinylbenzene. The influence of nature and concentration of the used comonomers and co-solvents on shape, size distributions and surface characteristics of the particles formed was investigated. Shapes and diameters of the particles were analyzed by DLS, TEM and SEM. The data of SEM and optical spectroscopy studies demonstrated that the synthesized particles were able to self-assemble into thin-film three-dimensional ordered structures. Finally, the structures under study are promising for development of sensor devices with optical response to acetone. 相似文献
4.
5.
Domino Staudinger/aza‐Wittig/Mannich Reaction: An Approach to Diversity of Di‐ and Tetrahydropyrrole Scaffolds 下载免费PDF全文
Dr. Anna S. Pavlova Dr. Olga A. Ivanova Dr. Alexey O. Chagarovskiy Nikolay S. Stebunov Dr. Nikolay V. Orlov Dr. Alexey N. Shumsky Dr. Ekaterina M. Budynina Dr. Victor B. Rybakov Prof. Dr. Igor V. Trushkov 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(50):17967-17971
A highly efficient and selective domino reaction producing valuable di‐ and tetrahydropyrrole‐based skeletons from azidoethyl‐substituted CH‐acids and (thio)carbonyl compounds has been developed. By involving the additional functional groups in starting compounds into the domino reaction or postmodification of the primary reaction products, the simple construction of the pharmaceutically relevant three‐ and polycyclic azaheterocyclic scaffolds was demonstrated. 相似文献
6.
V. S. Zhigalov L. E. Bykova V. G. Myagkov A. N. Pavlova M. N. Volochaev A. A. Matsynin G. S. Patrin 《Journal of Surface Investigation: X-ray, Synchrotron and Neutron Techniques》2020,14(1):47-53
The structure and magnetic properties of CoPt–Al2O3 nanocomposite films synthesized by the annealing of Al/(Co3O4 + Pt) bilayers on a MgO(001) substrate at 650°C in vacuum are investigated. The synthesized composite films contain ferromagnetic CoPt grains with an average size of 25–45 nm enclosed in a nonconducting Al2O3 matrix. The saturation magnetization (Ms ~ 330 G) and coercivity (Hc ≈ 6 kOe) of the films are measured in the film plane and perpendicular to it. The obtained films are characterized by a spatial rotational magnetic anisotropy, which makes it possible to arbitrarily set the easy magnetization axis in the film plane or perpendicular to it using a magnetic field stronger than the coercivity (H > Hc). 相似文献
7.
Prof. Dr. Frank Heinrich Aria Salyapongse Akari Kumagai Dr. Fernando G. Dupuy Karpur Shukla Dr. Anja Penk Prof. Dr. Daniel Huster Prof. Dr. Robert K. Ernst Dr. Anna Pavlova Prof. Dr. James C. Gumbart Prof. Dr. Berthony Deslouches Prof. Dr. Y. Peter Di Prof. Dr. Stephanie Tristram-Nagle 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(28):6247-6256
In the quest for new antibiotics, two novel engineered cationic antimicrobial peptides (eCAPs) have been rationally designed. WLBU2 and D8 (all 8 valines are the d -enantiomer) efficiently kill both Gram-negative and -positive bacteria, but WLBU2 is toxic and D8 nontoxic to eukaryotic cells. We explore protein secondary structure, location of peptides in six lipid model membranes, changes in membrane structure and pore evidence. We suggest that protein secondary structure is not a critical determinant of bactericidal activity, but that membrane thinning and dual location of WLBU2 and D8 in the membrane headgroup and hydrocarbon region may be important. While neither peptide thins the Gram-negative lipopolysaccharide outer membrane model, both locate deep into its hydrocarbon region where they are primed for self-promoted uptake into the periplasm. The partially α-helical secondary structure of WLBU2 in a red blood cell (RBC) membrane model containing 50 % cholesterol, could play a role in destabilizing this RBC membrane model causing pore formation that is not observed with the D8 random coil, which correlates with RBC hemolysis caused by WLBU2 but not by D8. 相似文献
8.
Tatyana Kovshova Nadezhda Osipova Anna Alekseeva Julia Malinovskaya Alexey Belov Andrey Budko Galina Pavlova Olga Maksimenko Shakti Nagpal Svenja Braner Harshvardhan Modh Vadim Balabanyan Matthias G. Wacker Svetlana Gelperina 《Molecules (Basel, Switzerland)》2021,26(4)
Targeted delivery of doxorubicin still poses a challenge with regards to the quantities reaching the target site as well as the specificity of the uptake. In the present approach, two colloidal nanocarrier systems, NanoCore-6.4 and NanoCore-7.4, loaded with doxorubicin and characterized by different drug release behaviors were evaluated in vitro and in vivo. The nanoparticles utilize a specific surface design to modulate the lipid corona by attracting blood-borne apolipoproteins involved in the endogenous transport of chylomicrons across the blood–brain barrier. When applying this strategy, the fine balance between drug release and carrier accumulation is responsible for targeted delivery. Drug release experiments in an aqueous medium resulted in a difference in drug release of approximately 20%, while a 10% difference was found in human serum. This difference affected the partitioning of doxorubicin in human blood and was reflected by the outcome of the pharmacokinetic study in rats. For the fast-releasing formulation NanoCore-6.4, the AUC0→1h was significantly lower (2999.1 ng × h/mL) than the one of NanoCore-7.4 (3589.5 ng × h/mL). A compartmental analysis using the physiologically-based nanocarrier biopharmaceutics model indicated a significant difference in the release behavior and targeting capability. A fraction of approximately 7.310–7.615% of NanoCore-7.4 was available for drug targeting, while for NanoCore-6.4 only 5.740–6.057% of the injected doxorubicin was accumulated. Although the targeting capabilities indicate bioequivalent behavior, they provide evidence for the quality-by-design approach followed in formulation development. 相似文献
9.
Olga L. Mezentseva Galina B. Slepchenko Elena V. Dorozhko Eugenia S. Moiseeva Vladimir P. Kryukovskiy Nikolay K. Zaycev 《Electroanalysis》2023,35(4):e202200252
A highly sensitive electrochemical sensor based on arenediazonium tosylates was designed to detect meldonium in urine. The effect of the concentration of ArN2+OTs− arenediazonium tosylate modifier and various substituents was studied. Basic operating parameters for voltammetric meldonium detection were established and the procedure for urine sample preparation was developed. The following values were obtained: limit of detection (LOD) 0.005 mg ⋅ L−1 (P=0.95) and limit of quantification (LOQ) 0.01 mg ⋅ L−1. The relationship between the analytical signal and meldonium concentration in the solution ranging from 0.01 to 400 mg ⋅ L−1 was described by a linear function. The meldonium concentration error did not exceed 18 %. The analysis time for a single urine sample was reduced to 15 minutes. 相似文献
10.
Elena V. Dorozhko Nikita A. Lunev Elena I. Korotkova Galina B. Slepchenko Olga I. Lipskikh Ekaterina I. Mikhnevich 《Electroanalysis》2023,35(9):e202300054
In this work two strategies for the synthesis of peroxidase silver conjugates for the qualitative and quantitative determination of immunoglobulins (IgG) to ixodid tick-borne borreliosis (ITBB) (Lyme disease) in human serum were proposed. The first approach for Ab-HRP@AgNP conjugate synthesis involved silver nanoparticles (Ag NPs) capped with a commercial peroxidase conjugate (Ab-HRP) by passive adsorption. The second strategy was based on the initial coupling of Ag NPs with human anti-species antibodies (Ab) by passive adsorption followed by the introduction of horseradish peroxidase (HRP) enzyme into the reaction mixture as a blocking reagent for Ab@AgNP@HRP conjugate synthesis. The formation of peroxidase silver conjugates was proved by UV/Vis spectroscopy and Transmission Electron Microscopy (TEM). The catalytic activity of Ab-HRP@AgNP and Ab@AgNP@HRP conjugates was evaluated by Michaelis-Menten kinetics. A commercially available 96-well microtiter plate with recombinant antigens to ITBB was used as a platform for immobilization of analyzed IgG. The HRP in Ab-HRP@AgNP conjugate was found to retain a sufficient level of activity for interaction with the H2O2 substrate to form an intensely colored reaction product. Therefore Ab-HRP@AgNP conjugate can be used in enzyme-linked immunosorbent assay (ELISA) with spectrophotometric detection of 3,3’,5,5’-Tetramethylbenzidine (TMB Ox) for quantitative determination of IgG to ITBB in human serum in the concentration range 12.5–800 ng ml−1 with LOD 2 ng ml−1. Ab@AgNP@HRP conjugate is recommended for the electrochemical determination of IgG to ITBB in human serum at LOD 3 ng ml−1 with registration of silver oxidation by linear sweep anodic stripping voltammetry (LSASV). Ag NPs in Ab-HRP@AgNP and Ab@AgNP@HRP conjugates do not change electrochemical activity during storage and can be used as an electrochemical label in LSASV method in case of HRP inactivation. The immunoassay based on peroxidase silver conjugates expands the analytical potential for the determination of IgG to ITBB especially during the period of increasing incidence. 相似文献