Article
Chemistry, Physical
Mingquan Xu, De-Liang Bao, Aowen Li, Meng Gao, Dongqian Meng, Ang Li, Shixuan Du, Gang Su, Stephen J. Pennycook, Sokrates T. Pantelides, Wu Zhou
Summary: By improving the stability and sensitivity of the instrument, we have successfully observed the specific vibrational signals between substitutional impurities and neighboring carbon atoms in monolayer graphene. This work allows for the direct observation of local phonon modes with chemical-bonding sensitivity, providing more insights into defect-induced physics in graphene.
Article
Chemistry, Multidisciplinary
Chen Lei, Andreas Erlebach, Federico Brivio, Lukas Grajciar, Zdenek Tosner, Christopher J. Heard, Petr Nachtigall
Summary: Solid state (ss-) Al-27 NMR is a valuable tool for characterizing zeolites, but its interpretation is complex and aluminum distributions are difficult to determine. Computational modeling has become popular to support experimental characterization, but simplifying assumptions are often made without justification. This study evaluates the effects of different models on the prediction of Al-27 NMR chemical shifts in zeolites and highlights the importance of operando modeling and considering factors like water loading, temperature, and cation characteristics. Machine learning regression is used to develop a relationship between chemical shifts and structural parameters, allowing for accurate prediction from dynamic simulations.
Article
Chemistry, Analytical
Pavel Krasnov, Victoria Ivanova, Darya Klyamer, Aleksandr Fedorov, Tamara Basova
Summary: Quantum chemical calculations were used to investigate the interaction between carbon nanotubes and zinc phthalocyanine molecules with ammonia. The results revealed that the sensor response of the hybrid materials to ammonia depends on the number of substituents in the phthalocyanine macrocycle and the interaction between ammonia and phthalocyanine molecules. The presence of an impurity band in the carbon nanotube's band gap was found to be the key feature determining the sensor response. Ammonia adsorption led to a decrease in the energy of this impurity band, resulting in lower electrical conductivity of the hybrid materials.
Article
Chemistry, Multidisciplinary
Juan Carlos Fuentes-Monteverde, Markus Noll, Akhi Das, Stefan Immel, Michael Reggelin, Christian Griesinger, Nilamoni Nath
Summary: Anisotropic NMR spectroscopy is a powerful tool for determining the configurations of synthetic and complex natural compounds. In addition to the relative configuration, the deduction of the absolute configuration is also an important goal. Investigating the enantiodiscriminating capabilities of chiral alignment media becomes essential. This study demonstrates the measurement of residual chemical shift anisotropies in chiral liquid crystals, providing valuable insights for determining the configurations of chiral analytes.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Optics
Sunita Joshi
Summary: A new coumarin-fused quinoline push-pull fluorescent probe was designed, synthesized and characterized. The ground-state and excited-state dipole moments were calculated and compared using DFT calculations. Both experimental and computational studies showed higher excited-state dipole moment values than corresponding ground-state value.
EUROPEAN PHYSICAL JOURNAL D
(2021)
Article
Materials Science, Multidisciplinary
Johan Tidholm, Ferenc Tasnadi, Igor A. Abrikosov
Summary: Using ab initio molecular dynamics simulations, the elastic properties of Ti0.5Al0.5N at high temperatures were studied, showing an increase in elastic anisotropy with temperature. Comparisons with TiN were made, and it was suggested that the symmetry imposed force constants approach combined with the temperature-dependent effective potential method is accurate for the hard coating material class Ti(1-x)AlxN.
Article
Biochemical Research Methods
David A. Nyenhuis, Charles D. Schwieters, Nico Tjandra
Summary: Paramagnetic NMR experiments, including the pseudocontact shift experiment, have become increasingly popular due to the development of new probes and labeling strategies. The pseudocontact shift experiment can provide valuable information about distances and orientations within or between molecules. However, the use of 1H/13C or 1H/15N PCS data in structure calculations is currently complicated by the contribution of residual chemical shift anisotropy. In this study, a corrected PCS energy term for the Xplor-NIH software package is presented, along with its suitability for refining the structure of ubiquitin labeled at residue 57 with a Tm-M8-SPy tag. The corrected energy term improves the quality of the fit for the 15N dataset, making it comparable to the 1H dataset.
JOURNAL OF MAGNETIC RESONANCE
(2022)
Article
Radiology, Nuclear Medicine & Medical Imaging
D. B. Berry, V. L. Galinsky, E. B. Hutchinson, J. P. Galons, S. R. Ward, L. R. Frank
Summary: This study investigates the sensitivity of double pulsed field gradient diffusion MRI to key features of muscle microstructure. Through simulations and experimental scans on a rat model of muscle hypertrophy, the study demonstrates that diffusion tensor subspace imaging analysis can accurately predict important microstructural features related to muscle function. The scalar value of spherical anisotropy (SA) shows a wider dynamic range compared to fractional anisotropy, making it more sensitive to changes in tissue microstructure.
MAGNETIC RESONANCE IN MEDICINE
(2023)
Article
Chemistry, Physical
Yifan Zhang, Xianwei Hu, Fengguo Liu, Jiaxin Yang, Liyu Chen, Wenju Tao, Aimin Liu, Zhongning Shi, Zhaowen Wang
Summary: In this study, the reaction process and reaction mechanism of the aluminothermic reduction of NaVO3 to prepare aluminum-vanadium intermediate alloy were investigated by experimental analysis and quantum chemical calculations. The study found that the reduction process of NaVO3 was a multi-step process and temperature played a critical role. The results showed that aluminum first interacted with NaVO3 to form an intermediate complex through electrostatic interaction, leading to the formation of aluminum-vanadium intermediate alloy.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Chemistry, Physical
Lekhan Lodhi, Jai Prakash Yadav, Toshio Yamazaki, Nghia Tuan Duong, Srinivasa L. Poojary, Krishna Kishor Dey, Yusuke Nishiyama, Manasi Ghosh
Summary: In this study, the structure and dynamics of quinine and its quasienantiomer quinidine were investigated using solid-state NMR measurements. The results showed significant variations in isotropic chemical shift, spin-lattice relaxation time, and CSA parameters for the three independent molecules of quinine. Quinidine exhibited distinct differences in its 13C CP-MAS SSNMR spectrum compared to quinine, and significant changes in the structure and dynamics of the quasienantiomers were observed.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Chemistry, Physical
Nisha Bamola, Mohit Bansal, Ramesh Ramachandran
Summary: Quantifying the NMR spectra of spin I=1/2 nuclei coupled to quadrupolar spins has been difficult in solid-state magic angle spinning (MAS) NMR experiments. Extracting chemical shift anisotropy (CSA) tensors from line-shapes of these nuclei has remained challenging due to the presence of both heteronuclear dipolar and quadrupolar interactions. A quantitative theory based on effective fields is proposed to deduce the optimal conditions for experiments involving recoupling and decoupling of heteronuclear dipolar interactions, and the derived analytic expressions provide a fast and beneficial approach for quantifying such experiments.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Nanoscience & Nanotechnology
Yilun Huang, Mouyi Weng, Qianming Gong, Kai Du, Dazhi Wang, Shijun Zhang, Changjiang Wu, Ming Zhao, Daming Zhuang, Hongwei Zhu, Ce-wen Nan
Summary: The study investigated the negative effects of decay of key structural components on the aging of SCs. It was found that the interaction between the electrode and separator could accelerate aging, especially under high charge-discharge current density. The research also revealed the intrinsic chemical aging mechanism of SCs through various analyses of fresh and aged key components.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Chemistry, Multidisciplinary
Krishna Kishor Dey, Lekhan Lodhi, Manasi Ghosh
Summary: Significant changes in the spin-lattice time and chemical shift anisotropy parameters have been observed in two independent molecules of atorvastatin calcium, indicating the coexistence of two different kinds of motional degrees of freedom. These changes enhance the solubility and bioavailability of the drug molecule. The use of solid-state NMR methodology quantifies for the first time the molecular dynamics of the two independent molecules in an asymmetric unit of atorvastatin calcium.
Article
Materials Science, Multidisciplinary
Xiaofan Du, Zhao Qian, Xiangfa Liu
Summary: In this study, Al-doped beta-SiC particles were synthesized in situ in Al-20Si-5C alloys using a liquid-solid multiphase reaction method. The morphological evolution of the particles and the influence of Al doping on the properties of the composites were investigated. Density functional theory calculations showed that the chemical bonding and mechanical properties of the doped SiC particles decreased with increased Al doping content. This work provides a new approach to improve the properties of aluminum matrix composites for potential lightweight applications.
RESULTS IN PHYSICS
(2022)
Article
Chemistry, Physical
Evgeniia E. E. Ondar, Mikhail V. V. Polynski, Valentine P. P. Ananikov
Summary: Water-soluble Pt complexes are critical in medicinal chemistry and catalysis, with cisplatin family drugs and hydrosylilation catalysts being notable examples. Understanding the activity mechanisms of these complexes requires reliable approaches for correlating structure with Pt-195 chemical shifts, which is currently challenging. In this study, a new workflow combining semiempirical calculations and machine learning was developed to predict Pt-195 chemical shifts of water-soluble Pt(II) and Pt(IV) complexes.
Article
Chemistry, Physical
Rongchun Zhang, Kamal H. Mroue, Ayyalusamy Ramamoorthy
JOURNAL OF CHEMICAL PHYSICS
(2015)
Article
Medicine, Research & Experimental
Ana K. Chattah, Rongchun Zhang, Kamal H. Mroue, Laura Y. Pfund, Marcela R. Longhi, Ayyalusamy Ramamoorthy, Claudia Garnero
MOLECULAR PHARMACEUTICS
(2015)
Article
Multidisciplinary Sciences
Anirban Ghosh, Bhisma Narayan Ratha, Nilanjan Gayen, Kamal H. Mroue, Rajiv K. Kar, Atin K. Mandal, Anirban Bhunia
Article
Multidisciplinary Sciences
Kamal H. Mroue, Yusuke Nishiyama, Manoj Kumar Pandey, Bo Gong, Erin McNerny, David H. Kohn, Michael D. Morris, Ayyalusamy Ramamoorthy
SCIENTIFIC REPORTS
(2015)
Article
Multidisciplinary Sciences
Aritreyee Datta, Anirban Ghosh, Cristina Airoldi, Paola Sperandeo, Kamal H. Mroue, Jesus Jimenez-Barbero, Pallob Kundu, Ayyalusamy Ramamoorthy, Anirban Bhunia
SCIENTIFIC REPORTS
(2015)
Article
Biochemistry & Molecular Biology
Rajiv K. Kar, Zuzana Gazova, Zuzana Bednarikova, Kamal H. Mroue, Anirban Ghosh, Ruiyan Zhang, Katarina Ulicna, Hans-Christian Siebert, Nikolay E. Nifantiev, Anirban Bhunia
Article
Biochemical Research Methods
Rongchun Zhang, Kamal H. Mroue, Ayyalusamy Ramamoorthy
JOURNAL OF MAGNETIC RESONANCE
(2016)
Article
Chemistry, Physical
Rajiv K. Kar, Kamal H. Mroue, Dinesh Kumar, Bimo A. Tejo, Anirban Bhunia
JOURNAL OF PHYSICAL CHEMISTRY B
(2016)
Article
Chemistry, Physical
Kamal H. Mroue, Jiadi Xu, Peizhi Zhu, Michael D. Morris, Ayyalusamy Ramamoorthy
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2016)
Article
Chemistry, Physical
Joshua T. Damron, Kortney M. Kersten, Manoj Kumar Pandey, Kamal H. Mroue, Jayasubba Reddy Yarava, Yusuke Nishiyama, Adam J. Matzger, Ayyalusamy Ramamoorthy
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2017)
Article
Chemistry, Physical
Shruti Mukherjee, Rajiv K. Kar, Ravi Prakash Reddy Nanga, Kamal H. Mroue, Ayyalusamy Ramamoorthy, Anirban Bhunia
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2017)
Article
Biochemical Research Methods
Kamal H. Mroue, Rongchun Zhang, Peizhi Zhu, Erin McNerny, David H. Kohn, Michael D. Morris, Ayyalusamy Ramamoorthy
JOURNAL OF MAGNETIC RESONANCE
(2014)
Article
Immunology
Mohamed H. M. Ali, Salman M. Toor, Fazle Rakib, Raghvendra Mall, Ehsan Ullah, Kamal Mroue, Prasanna R. Kolatkar, Khalid Al-Saad, Eyad Elkord
Article
Biochemistry & Molecular Biology
Olfa Khalifa, Kamal H. Mroue, Raghvendra Mall, Ehsan Ullah, Nayla S. Al-Akl, Abdelilah Arredouani
Summary: This study investigated the biochemical changes in a steatosis cell model treated or not with the GLP-1R agonist Exendin-4 using Fourier transform infrared (FTIR) spectroscopy and chemometric analyses. The results showed that Exendin-4 significantly reduces lipid accumulation in NAFLD cells and restores the biochemical alterations caused by oxidative stress. FTIR spectroscopy combined with chemometric analyses may offer new approaches for investigating the mechanisms of NAFLD.
Review
Chemistry, Multidisciplinary
Rongchun Zhang, Kamal H. Mroue, Ayyalusamy Ramamoorthy
ACCOUNTS OF CHEMICAL RESEARCH
(2017)