A5019299205- Advanced Thermoelectric Materials and Devices
- Pancreatic and Hepatic Oncology Research
- 2D Materials and Applications
- Heusler alloys: electronic and magnetic properties
- Topological Materials and Phenomena
- Graphene research and applications
- X-ray Diffraction in Crystallography
- Gallbladder and Bile Duct Disorders
- Rare-earth and actinide compounds
- Physics of Superconductivity and Magnetism
- Phase-change materials and chalcogenides
- Quantum and electron transport phenomena
- Advanced Radiotherapy Techniques
- Semiconductor materials and interfaces
- Renal cell carcinoma treatment
- Cancer Genomics and Diagnostics
- Advanced Condensed Matter Physics
- Effects of Radiation Exposure
- Pancreatitis Pathology and Treatment
- Intermetallics and Advanced Alloy Properties
- Lung Cancer Diagnosis and Treatment
- Thermal properties of materials
- Quantum many-body systems
- Bariatric Surgery and Outcomes
- Surgical site infection prevention
University Hospitals of North Midlands NHS Trust
2023-2024
Thomas Jefferson University
2022-2023
Royal Stoke University Hospital
2022-2023
Texas A&M University
2015-2021
Louisiana State University
2021
University of Houston
2020
University of Electronic Science and Technology of China
2020
Harbin Institute of Technology
2020
College Station Medical Center
2018
Sharif University of Technology
2015
We report $^{125}\mathrm{Te}$ NMR measurements of the topological quantum material ${\mathrm{ZrTe}}_{5}$. Spin-lattice relaxation results, well explained by a theoretical model Dirac electron systems, reveal that characteristic ${\mathrm{ZrTe}}_{5}$ is $T$ dependent, changing from weak insulator to strong as temperature increases. Electronic structure calculations confirm this ordering, reverse what has been proposed. results demonstrate gapless semimetal state occurring at Lifshitz...
We present a 63Cu and 65Cu NMR study of Cu12Sb4S13, the basis for tetrahedrite thermoelectric materials. In addition to electronic changes observed at Tc = 88 K metal–insulator transition, we find that locally there are significant structural occurring as temperature extends above Tc, which associate with Cu atom displacements away from symmetry positions. Spin-lattice relaxation rates (1/T1) dominated by quadrupolar process indicating anharmonic vibrational dynamics both below Tc. used...
We apply $^{125}\mathrm{Te}$ nuclear magnetic resonance (NMR) spectroscopy to investigate the Dirac semimetal ${\mathrm{ZrTe}}_{5}$. With NMR field parallel $b$ axis, we observe significant quantum effects. These include an abrupt drop at 150 K in spin-lattice relaxation rate. This corresponds a gap-opening transition carriers, likely indicating onset of excitonic pairing. Below 50 K, see more negative shift for ${\mathrm{Te}}_{z}$ bridging site, repopulation levels with spin polarized...
In this work, we report nuclear magnetic resonance (NMR) combined with density functional theory studies of the transition metal dichalcogenide ${\mathrm{ZrTe}}_{2}$. The measured NMR shift anisotropy reveals a quasi-two-dimensional behavior connected to topological nodal line close Fermi level. With field perpendicular ${\mathrm{ZrTe}}_{2}$ layers, can be well-fitted by combination enhanced diamagnetism and spin due high-mobility Dirac electrons. spin-lattice relaxation rates external both...
To investigate the electronic behavior and magnetic properties of NbFeSb, we have performed 93Nb NMR, specific heat measurements on NbFeSb samples treated at high temperatures. Magnetic combined with an observed Schottky anomaly changes in NMR line width indicate presence a 0.2% concentrated native defect stoichiometric samples. The origin these defects is believed to be due Fe antisites Nb sites. In addition, shift spin-lattice relaxation results below 200 K reveal Korringa-like response...
We report $^{59}$Co, $^{93}$Nb, and $^{121}$Sb nuclear magnetic resonance (NMR) measurements combined with density functional theory (DFT) calculations on a series of half-Heusler semiconductors, including NbCoSn, ZrCoSb, TaFeSb NbFeSb, to better understand their electronic properties general composition-dependent trends. These materials are interest as potentially high efficiency thermoelectric materials. Compared the other materials, we find that ZrCoSb tends have relatively large amount...
We report $^{59}\mathrm{Co}$ NMR and transport measurements on $n$-type filled skutterudites ${\mathrm{Ba}}_{x}{\mathrm{Yb}}_{y}{\mathrm{Co}}_{4}{\mathrm{Sb}}_{12}$ ${A}_{x}{\mathrm{Co}}_{4}{\mathrm{Sb}}_{12}\phantom{\rule{4pt}{0ex}}(A=\mathrm{Ba}$ or Sr), promising thermoelectric materials. The results demonstrate consistently that a shallow defect level near the conduction-band minimum dominates electronic behavior, in contrast to behavior of unfilled ${\mathrm{CoSb}}_{3}$. To analyze...
Abstract Aim Admissions in surgery is one of the most important part patient care pathway and sets trajectory for rest their stay. Without good documentation, decisions made can be missed out this will eventually lead to deficiency patient’s management. In audit we aim analyse documentation during admissions look at ways improve them. Method A retrospective review done admission 50 random upper gastrointestinal was assessed using principles from Take Ten Shine Toolkit. Change implemented...
$^{63}$Cu NMR measurements are reported for the Cu-rich phase of \ch{Cu_{12+x}Sb4S13} ($x \lesssim 2$) and compared to \ch{Cu12Sb4S13}. We identify signatures segregation into Cu-poor \approx 0$) phases, with metal-insulator transition observed in \ch{Cu12Sb4S13} suppressed phase. Based on $T_1$ $T_2$ measurements, results demonstrate Cu-ion hopping below room temperature an activation energy $\sim$150 meV phase, consistent superionic behavior. The also effects mobility but a larger barrier....
The Kondo-necklace model can describe magnetic low-energy limit of strongly correlated heavy fermion materials. There exist multiple energy scales in this corresponding to each phase the system. Here, we study quantum transition between Kondo-singlet and antiferromagnetic long-range ordered phase, show effect anisotropies terms information properties vanishing gap. We employ 'perturbative continuous unitary transformations' approach calculate gap spin-spin correlations for thermodynamic one,...
We present Cu NMR measurements of Ni-, Zn-, Mn-, and Te-substituted tetrahedrites, which show exceptionally low thermal conductivity high thermoelectric efficiency. The collective shift behavior demonstrates a common electronic for substituted materials distinct from that the insulating phase unsubstituted tetrahedrite, Cu12Sb4S13. results establish importance native defects in reducing residual carrier densities partially compensated compositions. In addition, quadrupolar T1–1 relaxation...