A5052669726- Ferroelectric and Piezoelectric Materials
- Acoustic Wave Resonator Technologies
- Microwave Dielectric Ceramics Synthesis
- Multiferroics and related materials
- Dielectric materials and actuators
- Optical Polarization and Ellipsometry
- Molecular spectroscopy and chirality
- Electronic and Structural Properties of Oxides
- Streptococcal Infections and Treatments
- Liquid Crystal Research Advancements
- Nonlinear Optical Materials Research
- Atmospheric chemistry and aerosols
- Advanced Sensor and Energy Harvesting Materials
- Crystallization and Solubility Studies
- Air Quality and Health Impacts
- Photoreceptor and optogenetics research
- Spectroscopy and Quantum Chemical Studies
- Innovative Energy Harvesting Technologies
- Solid-state spectroscopy and crystallography
- Magnetic and transport properties of perovskites and related materials
- Photorefractive and Nonlinear Optics
- Advances in Oncology and Radiotherapy
- Advanced ceramic materials synthesis
- Air Quality Monitoring and Forecasting
- Optical and Acousto-Optic Technologies
Friedrich-Alexander-Universität Erlangen-Nürnberg
2017-2024
Nagoya Institute of Technology
2014-2024
Johns Hopkins University Applied Physics Laboratory
2024
New York University
2015-2023
Idaho National Laboratory
2023
Materials Science & Engineering
2021
IFP Énergies nouvelles
2020
Taiyo Yuden (Japan)
2017-2020
Tsinghua University
2020
Instituto Andaluz de Ciencias de la Tierra
2019
Brown carbon (BrC), which may include secondary organic aerosol (SOA), can be a significant climate-forcing agent via its optical absorption properties. However, the overall contribution of SOA to BrC remains poorly understood. Here, correlations between oxidation level and properties are examined. was generated in flow reactor absence NOx by OH gas-phase precursors used as surrogates for anthropogenic (naphthalene, tricyclo[5.2.1.0(2,6)]decane), biomass burning (guaiacol), biogenic...
Functionalization (oxygen addition) and fragmentation (carbon loss) reactions governing secondary organic aerosol (SOA) formation from the OH oxidation of alkane precursors were studied in a flow reactor absence NO(x). SOA n-decane (n-C10), n-pentadecane (n-C15), n-heptadecane (n-C17), tricyclo[5.2.1.0(2,6)]decane (JP-10), vapors diesel fuel Southern Louisiana crude oil. Aerosol mass spectra measured with high-resolution time-of-flight spectrometer, which normalized yields,...
The functional properties of piezoelectric ceramic materials, such as barium titanate, are highly dependent on grain size. Lead-free polycrystalline Ba0.85Ca0.15Zr0.1Ti0.9O3 (BCZT) samples were prepared with a combination the hydrothermal method and spark plasma sintering to achieve sizes from 100 nm 10 μm by varying maximum temperature. In this range, transition nearly linear dielectric ferroelectric response can be seen in macroscopic electromechanical measurements, demonstrating...
Optical activity measurements of isotropic media average orientational dependencies light matter interactions. Crystals in the lab and oriented molecules silico reveal essential chemical quantities fullness their three dimensions.
In this study, the macroscopic mechanical behavior was characterized as a function of temperature (−150 °C to 400 °C) for polycrystalline (Na0.5K0.5)NbO3 with three dopant concentrations. Dopants can improve certain electromechanical properties and, in case NKN and Li+, shift orthorhombic-to-tetragonal phase transition lower temperatures. undoped NKN, LNKN6 6 mol. % additional dopants compared dependent dielectric response crystal structure. During loading, samples showed nonlinear...
Formulas for modeling ellipsometric measurements of bianisotropic crystals assume perfectly coherent plane wave illumination. As such, the finite coherence typical spectroscopic ellipsometers renders such formulas invalid thicker than a few micrometers. Reflection thick crystalline slabs show depolarization. Researchers have proposed strategies full accounting multiply reflected incoherent waves in anisotropic, arbitrarily oriented [Appl. Opt.41, 2521...
Abstract Ethylenediammonium sulfate (EDS) crystals were grown from aqueous solution and cleaved into thin (100–500 micron) plates. The 422 point group of EDS was confirmed by X‐ray diffraction. constitutive relations determined through generalized ellipsometry with an instrument that uses four photoelastic modulators (4PEM). optical rotation at 500 nm, for example, + 22.9°/mm along the optic axis − 12.1°/mm perpendicular to P 4 1 2 crystals. Enantiomorphous twins frequently form across (001)...
The influence of uniaxial compressive stress on small-signal relative permittivity and direct piezoelectric coefficient polycrystalline Li-modified (K0.5Na0.5)NbO3 (0, 2, 4 mol. % Li) was characterized as a function temperature from 25 to 450 °C. These data reveal corresponding anomalies in both the dielectric properties near well-known structural phase transitions (KxNa1 − x)NbO3. In particular, increasing found shift orthorhombic–tetragonal (TO−T) tetragonal–cubic (TC) boundaries higher...
Optical activity (OA) along the optic axis of crystalline benzil has been measured by many over past 150 years. However, OA anisotropy remains uncharacterized due to difficulties in sample preparation as well competition with linear birefringence (LB). The challenges associated measuring low-symmetry directions crystals have too often left scientists only average values nonresonant solution, i.e., specific rotations, which continue resist interpretation terms structure. Measuring facilitated...
In presenting a study of 1,438 children with rheumatic heart disease whom I have had the privilege to observe at three convalescent homes outside New York City over period twenty years, am mindful pitfalls one encounters in analysis records and figures realize that any conclusions arrived must be suggestive rather than final. Figures can often misleading but if properly evaluated may suggest trends help set up an index for formulation criteria. My hope is this intensive specialized care two...
This work presents the fabrication of dense polycrystalline barium titanate (BaTiO 3 , BT) for electromechanical transduction using robocasting and cold isostatic pressing (CIP). The use CIP as post‐treatment is proposed to eliminate defects increase density robocasted parts improve piezoelectric performance. For robocasting, pastes containing 50 52 vol% are developed; resulting green CIPed at 100 150 MPa. Using this technique, samples with BT52 MPa display a relative ≈98%, comparable...
Circular birefringence (CB) is generally responsible for only a small perturbation to the state of light polarization in crystals that also exhibit linear (LB). As such, magnetoelectric tensor gyration, which gives rise CB and optical activity, less well determined than electric permittivity models Mueller matrix. To visualize effect on polarimetric measurements, reported here are experimental mappings matrix new chiral crystal with accidental null LB at an accessible frequency. Single...
In this work, the creep behavior of (Na1/2Bi1/2)TiO3-0.07BaTiO3 was characterized as a function bias stress up to −500 MPa, revealing time-dependence stress-induced relaxor-to-ferroelectric long-range order transformation. Creep strain observed across range applied compressive levels, in particular at stresses approximately 50% above critical coercive stress, indicating significant transformation on ferroelectric order. The macroscopic is discussed conjunction with ex situ piezoresponse...
Optical crystallography of precipitated hot supersaturated solutions calcium sulphate shows oriented attachment gypsum crystals at homochiral facets.
The effect of uniaxial compressive stress on the crystal structure a 6 mol. % Li-doped (K,Na)NbO3 (LKNN6a) ceramic was investigated using in situ synchrotron X-ray diffraction, revealing stress-induced relative change monoclinic Pm and tetragonal P4mm phases. As such, phase transformations, addition to lattice deformation domain switching, are contributing factors for observed macroscopic mechanical behavior LKNN6a. stress-dependent diffraction data also demonstrates method mechanically...
The unipolar fatigue behavior of undoped Li0.06Na0.52K0.42NbO3 (LNKN6-a) and the same compound with additives (LNKN6-b) were observed. Unipolar cycling was performed between room temperature 150°C under a high electric field 4 kV/mm. LNKN6-a fatigued crack formation throughout examined range. switchable polarization 2Pr decreased for 20% (=2 µC/cm2) at 150°C. In contrast, mechanical degradation not observed in LNKN6-b. LNKN6-b 15% (=3.2 It should be noted that 50°C, fatigue-free over least...