Article
Food Science & Technology
Sixu Chen, Pengyang Wang, Lingling Wu, Marleny D. A. Saldana, Yang Gao, Wenxiu Sun
Summary: In this study, an antibacterial PBF film was prepared to effectively extend the shelf life of Mongolian cheese. The microbial diversity of cheese was also analyzed using high-throughput DNA sequencing.
FOOD PACKAGING AND SHELF LIFE
(2023)
Article
Chemistry, Multidisciplinary
Marc Alias-Rodriguez, Coen de Graaf, Miquel Huix-Rotllant
Summary: Research shows that xanthone undergoes rapid transitions in a very short period of time, with a sequential mechanism of internal conversion and intersystem crossing processes.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Article
Nanoscience & Nanotechnology
Farahnaz Maleki, Giovanni Di Liberto, Gianfranco Pacchioni
Summary: In this work, the pH- and facet-dependent surface chemistry of TiO2/water interfaces was studied using ab initio molecular dynamics simulations. Acid-base equilibrium constants were determined at the interface, allowing for estimation of the pH at the point of zero charge, an important experimental observable. The amount of H+, OH-, and adsorbed H2O species on the surfaces was predicted based on simulated equilibrium constants, providing insights into water splitting semi-reactions. The complex morphology of TiO2 particles was approximated by considering different surfaces.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Energy & Fuels
Renate Zapf-Gottwick, Matthias Zorn, Jessica Nover, Michael Koch, Carolin Feifel, Juergen H. Werner
Summary: The stability of CdTe depends on the pH of water-based solutions, the particle size and surface treatment of CdTe particles. Smaller particles lead to faster leaching. Chemical treatments can modify the surface of CdTe particles and their leaching behavior.
Article
Chemistry, Inorganic & Nuclear
Shi-Hui Li
Summary: A new Cd(II) polymer, [Cd(btc)(4,4'-bipyridine)](n) 1, was synthesized under hydrothermal conditions. The compound forms a three-dimensional network with 4,4'-bipyridine ligands and btc(4-) anions. The elemental analyses, infrared spectroscopy, thermogravimetric analysis, and powder X-ray diffraction properties of 1 were also investigated.
INORGANIC AND NANO-METAL CHEMISTRY
(2022)
Article
Polymer Science
Taijun Jiang, Jun Peng, Jin Wang, Jun Yang, Guangsheng Zeng
Summary: The aim of this study was to prepare copolyimide films with low thermal expansion coefficient by incorporating PMDA into the polymer backbones. The results showed that adding PMDA increased the glass transition temperature of the polymers but narrowed the service temperature range.
POLYMER SCIENCE SERIES A
(2022)
Article
Chemistry, Physical
Vincent J. Ovalle, Matthias M. Waegele
Summary: Understanding the effects of solution pH on multiproton/electron transfer reactions at aqueous electrolyte/electrode interfaces has been a longstanding research focus. Recent interest has been driven by observations of how reaction selectivity and rates of electrocatalytic processes can change with electrolyte pH. pH gradients near electrodes, combined with electrode surface chemistry dependence on pH, can result in complex feedback between catalyzed reactions and local pH conditions.
JOURNAL OF PHYSICAL CHEMISTRY C
(2021)
Article
Biochemistry & Molecular Biology
Olga Kravchenko, Todd C. Sutherland, Belinda Heyne
Summary: This study highlighted the importance of buffer specific effects on both the photobleaching and the singlet oxygen quantum yields of a dye in aqueous environments. The results show that specific buffer effects cannot be neglected, as different chemical buffers significantly impact the photoproduct of the dye.
PHOTOCHEMISTRY AND PHOTOBIOLOGY
(2022)
Article
Chemistry, Multidisciplinary
Hossam N. Akl, Dina Salah, Hesham S. Abdel-Samad, Ayman A. Abdel Aziz, Ayman A. Abdel-Shafi
Summary: The photophysical characteristics of homoleptic ruthenium(II) phenanthroline derivatives in aqueous medium were investigated. The lifetimes of the studied complexes' excited 3MLCT state were highly sensitive to the substituents on the phenanthroline ligand and varied from 0.96 ms to 2.97 ms. The quenching of the complexes' excited states by molecular oxygen was studied, with quenching rate constants ranging from 1.02 to 4.83 x 10(9) M-1 s(-1). The singlet oxygen quantum yields and corresponding efficiencies were also determined.
Review
Physics, Atomic, Molecular & Chemical
Joerg Matysik, Yonghong Ding, Yunmi Kim, Patrick Kurle, Alexandra Yurkovskaya, Konstantin Ivanov, A. Alia
Summary: Photo-CIDNP is a phenomenon of nuclear polarization created by the spin-chemical evolution of spin-correlated radical pairs, which can occur in gases, liquids, and solids. The solid-state photo-CIDNP effect observed under magic-angle spinning has led to the development of photo-CIDNP MAS NMR as an analytical method.
APPLIED MAGNETIC RESONANCE
(2022)
Article
Physics, Atomic, Molecular & Chemical
Konstantin L. Ivanov, Alexandra V. Yurkovskya, Natalya N. Fishman, Aleksey S. Kiryutin, Renad Z. Sagdeev, Hans-Martin Vieth
Summary: CIDNP is a method used to study spin-dependent radical reactions by analyzing NMR signals of their products, with coherent polarization transfer commonly occurring in low magnetic fields. This polarization transfer can efficiently polarize spins that do not acquire CIDNP directly.
APPLIED MAGNETIC RESONANCE
(2022)
Article
Chemistry, Physical
Natalya N. Fishman, Olga B. Morozova, Hans- Martin Vieth, Alexandra V. Yurkovskaya
Summary: This study investigated the reduction of short-lived thymine radicals by tryptophan and N-acetyl tryptophan in aqueous solution across a wide pH range. The results provide insights into the chemical DNA repair process and reveal the reaction kinetics of the reduction reactions.
JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY
(2022)
Article
Chemistry, Physical
Vitaly P. Kozienko, Alexey S. Kiryutin, Alexandra V. Yurkovskaya
Summary: Parahydrogen induced polarization (PHIP) is a powerful tool for enhancing weak nuclear magnetic resonance signals. This study proposes a facile route to increase the performance of PHIP transfer in experiments by optimizing the field sweep. The optimization allows for increased polarization of C-13 in complex spin systems.
JOURNAL OF CHEMICAL PHYSICS
(2022)
Article
Chemistry, Inorganic & Nuclear
V. V. Garaeva, K. A. Spiridonov, I. A. Nikovskii, A. S. Peregudov, A. S. Kiryutin, A. Yurkovskaya, A. A. Polezhaev, V. V. Novikov
Summary: A possibility to generate spin polarization of F-19 nuclei in counterions that do not form covalent bonds with the metal center is shown for the first time in newly synthesized iridium complexes through reversible binding with the substrate and parahydrogen.
RUSSIAN JOURNAL OF COORDINATION CHEMISTRY
(2022)
Article
Biochemistry & Molecular Biology
Veronika V. V. Zlobina, Alexey S. S. Kiryutin, Igor A. A. Nikovskiy, Oleg I. I. Artyushin, Vitaly P. P. Kozinenko, Alexander S. S. Peregudov, Alexandra V. V. Yurkovskaya, Valentin V. V. Novikov
Summary: Parahydrogen-induced nuclear polarization significantly enhances the sensitivity of NMR spectroscopy for medical diagnostics and enables the creation of new probes for magnetic resonance imaging. In this study, unsaturated derivatives of phosphoric acid, propargyl, and allyl phosphates, are proposed as precursors for biocompatible hyperpolarized probes. The polarization transfer to H-1 and P-31 nuclei of their hydrogenation products using ALTADENA, PASADENA, and the PH-ECHO-INEPT+ pulse sequence of NMR spectroscopy resulted in a highly amplified signal, which is among the largest for parahydrogen-induced nuclear polarization transfer to the P-31 nucleus.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2023)
Article
Biochemistry & Molecular Biology
Anton. L. L. Popov, Irina. V. V. Savintseva, Taisiya. O. O. Kozlova, Olga. S. S. Ivanova, Ivan. V. V. Zhukov, Alexander. E. E. Baranchikov, Alexandra. V. V. Yurkovskaya, Andrey. A. A. Savelov, Artem. M. M. Ermakov, Nelli. R. R. Popova, Konstantin. L. L. Ivanov, Vladimir. K. K. Ivanov
Summary: Recently, there has been a lot of interest in using human mesenchymal stem cells (hMSCs) as potential therapies for socially significant diseases. However, the biological mechanisms of hMSC action after transplantation are still not well understood. This study reports on the use of heavily gadolinium-doped cerium oxide nanoparticles as a non-toxic and effective theranostic tool for tracking hMSCs using magnetic resonance imaging (MRI).
Article
Chemistry, Physical
Olga B. Morozova, Natalya N. Fishman, Alexandra V. Yurkovskaya
Summary: This study describes the application of time-resolved chemically induced dynamic nuclear polarization (TR CIDNP) in determining the bimolecular rate constants of triplet quenching. A known quenching rate constant was used as a reference to calculate the desired rate constants. The experiment focused on the quenching reaction of the triplet excited photosensitizer TCBP by histidine-containing compounds.
Article
Chemistry, Physical
Bogdan A. Rodin, Vineeth Thalakottoor, Mathieu Baudin, Nicolas Birilirakis, Geoffrey Bodenhausen, Alexandra V. Yurkovskaya, Daniel Abergel
Summary: Dynamical nuclear polarization (DNP) is a powerful method for polarizing spin-bearing nuclei through transferring electron polarization via microwave irradiation. In this study, the effects of energy transfer and spin temperature between proton (H) and deuterium (D) nuclei in DNP experiments were investigated using protonated or deuterated TEMPOL radicals as polarizing agents. The kinetic parameters and heat capacities of different reservoirs were analyzed to predict the behavior of heteronuclei. Experimental results also provided insights into the hidden spins that are not directly observable due to their proximity to the radicals.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Chemistry, Physical
Olga B. Morozova, Alexandra V. Yurkovskaya
Summary: This study investigated the reduction of carnosine radicals in neutral and basic aqueous solutions by l-tryptophan, N-acetyl tryptophan, and the Trp-Gly peptide using time-resolved chemically induced dynamic nuclear polarization (TR CIDNP). The reduction reaction rate constants were found to be influenced by the protonation state of the non-reacting β-alanine residue of carnosine radicals. Clear differences were observed compared to the reduction of histidine and N-acetyl histidine radicals, as well as the reduction of radicals derived from Gly-His, a homologue of carnosine.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Chemistry, Physical
Olga B. Morozova, Maksim P. Geniman, Mikhail S. Panov, Natalya N. Fishman, Alexandra V. Yurkovskaya, Peter S. Sherin
Summary: This work investigates the sites of H/H+ transfer within kynurenic acid (KNA) using the time-resolved chemically induced dynamic nuclear polarization (TR CIDNP) method. Density functional theory (DFT) calculations reveal that the KNA anion radical exists in two tautomeric forms, with H/H+ transfer to the carbonyl oxygen of the keto- or oxo-quinolinate forms, and without any significant H/H+ transfer to the nitrogen of the enol form.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2022)
Review
Chemistry, Multidisciplinary
Gerd Buntkowsky, Franziska Theiss, Jonas Lins, Yuliya A. Miloslavina, Laura Wienands, Alexey Kiryutin, Alexandra Yurkovskaya
Summary: Nuclear Magnetic Resonance (NMR) spectroscopy and Magnetic Resonance Imaging (MRI) are essential analytical and diagnostic tools with a wide range of applications. However, the low sensitivity of magnetic resonance poses a major challenge in various fields. Parahydrogen induced polarization (PHIP) is a cost-effective method to enhance signal by utilizing chemical reactions. This article provides an overview of PHIP techniques and reviews current literature on method developments and applications.