Article
Chemistry, Physical
N. N. Smirnova, A. V. Markin, S. S. Sologubov, S. A. Milenin, E. A. Tatarinova, A. M. Muzafarov
Summary: The study investigates the thermodynamic properties of a fourth-generation carbosilane dendrimer through determination and analysis of its heat capacity-temperature dependence, revealing anomalous changes and transitions within specific temperature ranges. Comparative analysis is also conducted on dendrimers with different molecular skeletons and terminal groups to understand their thermodynamic behaviors.
RUSSIAN JOURNAL OF PHYSICAL CHEMISTRY A
(2022)
Article
Biochemistry & Molecular Biology
Shunrou Tokonami, Yusuke Nakasone, Masahide Terazima
Summary: Blue-light sensor FLUF is a common domain found in many photosensor proteins. The study focused on understanding the stability of the oligomeric form of SyPixD and the impact of N- and C-terminal sequences. It was found that a few residues at the N-terminus can greatly affect decamer stability, while truncating C-terminal sequences also destabilizes the structure. The dissociation reaction dynamics were studied and showed that the C-terminus plays a role in the conformational change of the decamer.
Article
Geochemistry & Geophysics
Lidong Shi, Lidong Sun, Liang Yang, Jinshuang Xu, Changpeng Du, Fangwen Chen
Summary: This study evaluated the potential for oil and gas resources in the deep fault depression of the Northern Songliao Basin by examining shale samples from the fourth member of the Yingcheng Formation. The organic geochemical characteristics, hydrocarbon generation rates, and hydrocarbon generation periods of the shale were studied. The results showed that the high parts of the local structure in the South Shuangcheng Fault Depression are favorable areas for the exploration of shale oil and gas in the K(1)yc(4) layer.
Article
Materials Science, Multidisciplinary
A. Bezold, H. J. Stone, C. M. F. Rae, S. Neumeier
Summary: The lattice misfit between phases in nickel-based superalloys affects their microstructural evolution and mechanical properties. This study investigates the lattice misfit of highly alloyed Ru-containing 4th generation Ni-based superalloys using in situ X-ray diffraction at high temperatures. The results indicate a unique temperature dependence and show that the lattice misfit values become less negative above 900 degrees C.
METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE
(2022)
Article
Physics, Multidisciplinary
Alexey A. Polotsky, Anna S. Ivanova
Summary: This theoretical study investigates the adsorption of a single homopolymer chain with bending stiffness on a homogeneous planar surface using the lattice model and generating functions approach. The bending energy and stiffness parameter have non-monotonic effects on the adsorption transition temperature and the fraction of adsorbed units.
PHYSICA A-STATISTICAL MECHANICS AND ITS APPLICATIONS
(2021)
Article
Engineering, Chemical
Anastasia Penkova, Anna Kuzminova, Mariia E. Dmitrenko, Victoria A. Surkova, Vladislav P. Liamin, Denis A. Markelov, Andrei Komolkin, Daria Y. Poloneeva, Anastasia Laptenkova, Artem A. Selyutin, Anton S. Mazur, Alexei Emeline, Sabu Thomas, Sergey S. Ermakov
Summary: The study successfully developed highly methanol-permeable pervaporation membranes through modification of polymer membranes and preparation of supported membranes, achieving optimal industrial performance characteristics in the experiment.
SEPARATION AND PURIFICATION TECHNOLOGY
(2021)
Article
Chemistry, Physical
Leonid I. Klushin, Alexander M. Skvortsov, Alexey A. Polotsky, Anna S. Ivanova, Friederike Schmid
Summary: A novel class of responsive polymer brushes with controllable grafting density has been proposed in this study, using end-grafted polymer chains that have an affinity to the substrate. The dense layer and the outer brush can be seen as coexisting microphases, with the effective grafting density controlled by adsorption strength. Numerical self-consistent field calculations and scaling arguments demonstrate the reversible and controlled changes in grafting density in response to environmental parameters.
JOURNAL OF CHEMICAL PHYSICS
(2021)
Review
Polymer Science
Denis A. Markelov, Anna S. Semisalova, Mikhail A. Mazo
Summary: Dendrimers are tree-like symmetric macromolecules with unique properties, attracting researchers' interest. Differences in structure and conformation can be influenced by solvent selectivity and compatibility of terminal and core groups, leading to the formation of regions with lower polymer density inside the dendrimer.
MACROMOLECULAR CHEMISTRY AND PHYSICS
(2021)
Article
Materials Science, Multidisciplinary
Mariia Dmitrenko, Anna Kuzminova, Andrey Zolotarev, Vladislav Liamin, Denis Markelov, Konstantin Semenov, Tatiana Plisko, Alexandr Bildyukevich, Anastasia Penkova
Summary: The study focused on developing novel pervaporation membranes for dehydration, utilizing a blend of hydroxyethyl cellulose (HEC)/polyvinyl alcohol (PVA) and fullerene derivatives. The optimized cross-linked membrane showed promising transport properties in the pervaporation dehydration of isopropanol, with high water content in the permeate.
JOURNAL OF MATERIALS RESEARCH
(2021)
Article
Polymer Science
Nadezhda N. Sheveleva, Valeriy V. Bezrodnyi, Sofia E. Mikhtaniuk, Oleg Shavykin, Igor M. Neelov, Irina I. Tarasenko, Mikhail A. Vovk, Mariya E. Mikhailova, Anastasia Penkova, Denis A. Markelov
Summary: This study investigated the orientational mobility of collapsed and swollen dendrimers using NMR relaxation experiments and atomistic simulations, revealing that volume interactions suppress internal local mobility while reorientation occurs due to the rotation of the dendrimer as a whole. These findings suggest that considering segmental mobility is crucial for interpreting the mobility of CH2 groups observed in NMR experiments.
Article
Engineering, Chemical
Mariia Dmitrenko, Anna Kuzminova, Andrey Zolotarev, Denis Markelov, Andrei Komolkin, Evgeniia Loginova, Tatiana Plisko, Katsiaryna Burts, Alexandr Bildyukevich, Anastasia Penkova
Summary: This study focuses on improving the performance of polyacrylonitrile (PAN) membranes in ultrafiltration through the introduction of TiO2 particles. Different methods of TiO2 immobilization have varying effects on the structure and performance of PAN membranes.
SEPARATION AND PURIFICATION TECHNOLOGY
(2022)
Article
Biochemistry & Molecular Biology
Nadezhda N. Sheveleva, Irina I. Tarasenko, Mikhail A. Vovk, Mariya E. Mikhailova, Igor M. Neelov, Denis A. Markelov
Summary: This paper studies two lysine-based peptide dendrimers with Lys-His-Arg and Lys-Arg-His repeating units and terminal lysine groups. The combination of histidine and arginine in these dendrimers could be important for biomedical applications, such as preventing dendrimer aggregation and facilitating dendrimer penetration through cell membranes. The synthesis of these dendrimers is described, and their structure is confirmed using 1D and 2D Nuclear Magnetic Resonance (NMR) spectroscopy. NMR spectroscopy and relaxation are used to investigate the structural and dynamic properties of these dendrimers and compare them with previously studied dendrimers with Lys-2Arg and Lys-2His repeating units. The results show that both Lys-His-Arg and Lys-Arg-His dendrimers exhibit pH-sensitive conformation and dynamics. The Lys-His-Arg dendrimer, which has a similar conformation to the more hydrophobic Lys-2His dendrimer, could be a more suitable candidate as a pH-sensitive nanocontainer for drug delivery compared to Lys-2His and Lys-Arg-His dendrimers.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2023)
Article
Polymer Science
Nadezhda N. Sheveleva, Andrei V. Komolkin, Denis A. Markelov
Summary: In this study, the shear-stress relaxation of second generation PAMAM and PPI dendrimer melts was investigated through atomistic molecular dynamics simulation. The time dependences of relaxation modulus G(t) and the frequency dependences of storage G'(omega) and loss G''(omega) moduli were obtained and compared with a similar dendrimer of the same generation. The results showed that the chemical structure of the dendrimer segments strongly influenced their mechanical relaxation, with hydrogen bonding in PAMAM dendrimers leading to entanglement of macromolecules and slowing down of mechanical relaxation and rotational diffusion.
Article
Polymer Science
Anna Kuzminova, Mariia Dmitrenko, Andrey Zolotarev, Denis Markelov, Andrei Komolkin, Roman Dubovenko, Artem Selyutin, Jiangjiexing Wu, Rongxin Su, Anastasia Penkova
Summary: Membrane technology is actively developing in modern societies, allowing for the separation of various mixtures in industrial tasks. This study focuses on the development of effective membranes based on PVDF by modifying it with different nanoparticles. Two types of membranes were developed: dense membranes for pervaporation and porous membranes for ultrafiltration. The optimal nanoparticle content in the PVDF matrix was determined. The properties of these membranes were studied using various techniques, and the transport properties of the membranes were evaluated.
Article
Chemistry, Physical
Vladimir Y. Bazaikin, Andrei Komolkin, Denis A. Markelov
Summary: By modifying polymer membranes with special nanoparticles, the transport properties can be improved, resulting in higher efficiency in the separation and purification of mixtures.
JOURNAL OF MOLECULAR LIQUIDS
(2023)
Article
Chemistry, Physical
Naira R. Khusnutdinova, Denis A. Markelov
Summary: The translation mobility of poly(butylcarbosilane) dendrimers in a chloroform solution is studied using molecular dynamics simulations. Traditional methods for calculating the diffusion coefficient and hydrodynamic radius (Rh) of dendrimers often face difficulties and yield incorrect results. By considering rotational diffusion, an Rh similar to experimental data is obtained, which is practically independent of simulation parameters.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Chemistry, Physical
Naira R. Khusnutdinova, Denis A. Markelov
Summary: In this study, the translational mobility of poly(butylcarbosilane) dendrimers in chloroform solution was investigated using molecular dynamics simulations. Different methods for estimating the hydrodynamic radius (Rh) of dendrimers were discussed, and it was found that considering rotational diffusion provides accurate results independent of simulation box size and other parameters.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Chemistry, Physical
Nadezhda N. Sheveleva, Maxim Dolgushev, Erkki Lahderanta, Denis A. Markelov
Summary: Functionalizing the internal structure of dendrimers can result in changes in their properties. This study investigates the rheological behavior of functionalized dendrimer melts and finds that functionalized dendrimers behave like colloidal particles in crowded environments.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2022)
Article
Chemistry, Physical
Artyom D. Glova, Sofya D. Melnikova, Anna A. Mercurieva, Sergey V. Larin, Victor M. Nazarychev, Alexey A. Polotsky, Sergey V. Lyulin
Summary: The study found that the free branches of the branched oligolactide (OLA) chains tend to fold back towards the cellulose nanoparticles (CNPs) due to dipole-dipole interactions, but there was no significant difference in the effectiveness of covering the filler surface with grafted branched or linear OLA chains. In terms of the expelling ability of the grafted chains and the interaction between polylactide (PLA) and CNP or OLA, linear chains performed better than branched chains in intermediate or dense grafting scenarios.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2021)
