In-plane tensile strain was reported to enhance the ferroelectricity of HfZrO thin films by promoting the formation of a polar orthorhombic (PO-) phase. However, its origin remains yet to be identified unambiguously, although a strain-related thermodynamic stability variation was reported. This work explores the kinetic effects that have been overlooked to provide a precise answer to the problem, supplementing the thermodynamic calculations.
View Article and Find Full Text PDFVarious sensor applications have been developed for protection against hazardous environments, and research on functional materials to enhance performance has also been pursued. The M13 bacteriophage (M13) has found utility in sensor applications like disease diagnosis and detection of harmful substances due to its potential for controlling interaction with target substances through adjustments in electrochemical and mechanical properties via genetic engineering technology. However, while optimizing reactivity or binding affinity between M13 and target materials is crucial for sensor performance enhancement, precise dynamic measurement methods for this were lacking.
View Article and Find Full Text PDFThe ligand engineering for single-atom catalysts (SACs) is considered a cutting-edge strategy to tailor their electrocatalytic activity. However, the fundamental reasons underlying the reaction mechanism and the contemplation for which the actual active site for the catalytic reaction depends on the pyrrolic and pyridinic N ligand structure remain to be fully understood. Herein, we first reveal the relationship between the oxygen reduction reaction (ORR) activity and the N ligand structure for the manganese (Mn) single atomic site by the precisely regulated pyrrolic and pyridinic N coordination environment.
View Article and Find Full Text PDFNeuromorphic computing promises an energy-efficient alternative to traditional digital processors in handling data-heavy tasks, primarily driven by the development of both volatile (neuronal) and nonvolatile (synaptic) resistive switches or memristors. However, despite their energy efficiency, memristor-based technologies presently lack functional tunability, thus limiting their competitiveness with arbitrarily programmable (general purpose) digital computers. This work introduces a two-terminal bilayer memristor, which can be tuned among neuronal, synaptic, and hybrid behaviors.
View Article and Find Full Text PDFThe nature of the conducting filament (CF) with a high concentration of oxygen vacancies (Vs) in oxide thin film-based resistive random access memory (RRAM) remains unclear. The Vs in the CF have been assumed to be positively charged (V) to explain the field-driven switching of RRAM, but V clusters in high concentration encounter Coulomb repulsion, rendering the CF unstable. Therefore, this study examined the oxidation state of Vs in the CF and their effects on the switching behavior density functional theory calculations using a Pt/TiO/Ti model system.
View Article and Find Full Text PDFBiosens Bioelectron
January 2024
Metabolome analysis has gained widespread application in disease diagnosis owing to its ability to provide comprehensive information, including disease phenotypes. In this study, we utilized 3D superstructures fabricated through evaporation-induced microprinting to analyze the metabolome for glaucoma diagnosis. 3D superstructures offer the following advantages: high hotspot density per unit volume of the structure extending from two to three dimensions, excellent signal repeatability due to the reproducibility and defect tolerance of 3D printing, and high thermal stability due to the PVP-enclosed capsule form.
View Article and Find Full Text PDFAlthough single-layer transition-metal dichalcogenides with novel valley functionalities are a promising candidate to realize valleytronic devices, the essential understanding of valley depolarization mechanisms is still incomplete. Based on pump-probe experiments performed for MoSe2 and WSe2 monolayers and corroborating analysis from density functional calculations, we demonstrate that coherent phonons at the K-point of the Brillouin zone can effectively mediate the valley transfer of electron carriers. In the MoSe2 monolayer case, we identify this mode as the flexural acoustic ZA(K) mode, which has broken inversion symmetry and thus can enable electron spin-flip during valley transfer.
View Article and Find Full Text PDFAnaerobic digestion is the preferred method for treating sewage sludge because of its ability to reduce sludge volume and produce biogas. However, conventional anaerobic digestion has a long retention time and low degradation rate. In recent years, hydrothermal treatment has been used to improve the hydrolysis of sewage sludge and biogas production.
View Article and Find Full Text PDFNanomaterials (Basel)
February 2020
Interfacial bubbles are unintentionally created during the transfer of atomically thin 2D layers, a required process in the fabrication of van der Waals heterostructures. By encapsulating a WSe monolayer in hBN, we study the differing photoluminescence (PL) properties of the structure resulting from bubble formation. Based on the differentiated absorption probabilities at the bubbles compared to the pristine areas, we demonstrate that the visibility of the bubbles in PL mapping is enhanced when the photoexcitation wavelength lies between the n = 1 and n = 2 resonances of the A-exciton.
View Article and Find Full Text PDFWe report a cavity-dumped optical parametric oscillator (OPO) with a ring-type cavity configuration, which is based on periodically poled lithium niobate gain synchronously pumped by a mode-locked Ti:sapphire laser. Because of reduced cavity loss and group velocity dispersion inherent to ring-cavity employment, a wide wavelength tuning capability from 1.02 to 1.
View Article and Find Full Text PDFFrequency-dependent dielectric constant dispersion of monolayer WSe, ε(ω)=ε(ω)+i ε(ω), was obtained from simultaneously measured transmittance and reflectance spectra. Optical transitions of the trion as well as A-, B-, and C-excitons are clearly resolved in the ε spectrum. A consistent Kramers-Kronig transformation between the ε and ε spectra support the validity of the applied analysis.
View Article and Find Full Text PDFWe report surface plasmon (SP) lasing in metal/semiconductor nanostructures, where one-dimensional periodic silver slit gratings are placed on top of an InGaAsP layer. The SP nature of the lasing is confirmed from the emission wavelength governed by the grating period, polarization analysis, spatial coherence, and comparison with the linear transmission. The excellent performance of the device as an SP source is demonstrated by its tunable emission in the 400-nm-wide telecom wavelength band at room temperature.
View Article and Find Full Text PDFInelastic electron tunneling spectroscopy is a powerful technique for investigating lattice dynamics of nanoscale systems including graphene and small molecules, but establishing a stable tunnel junction is considered as a major hurdle in expanding the scope of tunneling experiments. Hexagonal boron nitride is a pivotal component in two-dimensional Van der Waals heterostructures as a high-quality insulating material due to its large energy gap and chemical-mechanical stability. Here we present planar graphene/h-BN-heterostructure tunneling devices utilizing thin h-BN as a tunneling insulator.
View Article and Find Full Text PDFAn optical parametric oscillator (OPO) based on magnesium-oxide-doped periodically poled lithium niobate (MgO:PPLN) is demonstrated to deliver visible femtosecond pulses, which were created through the intra-cavity nonlinear interactions within the PPLN itself. The signal from the OPO produces femtosecond pulses in the near-infrared region tunable from 1050 to 1600 nm. Visible femtosecond pulses in the range of 522-800 nm and those of 455-540 nm, respectively, were generated via second-harmonic generation (SHG) of signal photons and through sum-frequency generation (SFG) of pump and signal photons.
View Article and Find Full Text PDFWe demonstrate strong modulation of the transmission around the surface plasmon polariton (SPP) resonance in metal/semiconductor hybrid nanostructures based on Ag film on top of InGaAs. The change in the real and imaginary parts of the refractive index due to photoexcited carriers in InGaAs generates a shift in the SPP resonance and enhanced transmission near the SPP resonance. Temporal evolution of the complex refractive index was traced by comparing the transient transmission with finite-difference time-domain (FDTD) simulations.
View Article and Find Full Text PDFThe precipitation reaction between the orthophosphate and Fe2+ ions was studied to describe the optimum condition for the removal of orthophosphate from the aqueous solution. The effects of pH, Fe:P molar ratio, and alkalinity were evaluated for the initial orthophosphate concentrations in the range from 1.55 to 31.
View Article and Find Full Text PDFEthnopharmacological Relevance: Along with increase of herbal medicine use worldwide, the safety of traditional herbal medicines frequently becomes a medical issue.
Aim Of The Study: This study aimed to investigate the incidence of herbal medicine-induced adverse effects on liver functions.
Subjects And Methods: A prospective study was performed with 313 inpatients (87 male and 226 female) receiving herbal prescriptions during hospitalization.
Background: Non-small cell lung cancer (NSCLC) stages over IIIb still remain as an intractable disease. Survival rate of NSCLC stages over IIIb could be increased through chemotherapy and radiation, but results are not satisfactory. Oriental medicine herbal formula, HangAm-Dan (HAD) has been developed for anti-tumor purpose and several previous studies have already reported its effects.
View Article and Find Full Text PDFJ Acupunct Meridian Stud
September 2010
This experimental study was performed to investigate the antitumor effect of skin of venenum bufonis (SVB) in NCI-H460 human lung cancer cell xenografted nude mice. NCI-H460 cell lines were cultured and then xenografted into nude mice. Mice were divided into four groups: SVB (0.
View Article and Find Full Text PDFThe effect of chemical oxygen demand/sulfate (COD/SO(4)(2-)) ratio on fermentative hydrogen production using enriched mixed microflora has been studied. The chemostat system maintained with a substrate (glucose) concentration of 15 g COD L(-1) exhibited stable H(2) production at inlet sulfate concentrations of 0-20 g L(-1) during 282 days. The tested COD/SO(4)(2-) ratios ranged from 150 to 0.
View Article and Find Full Text PDF