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Migration and plugging laws of plugging-selection balls in fine profile control process of layered waterflooding wells
Clinical features, pathological characteristics, and prognosis of patients with IgA nephropathy complicated with nephrotic syndrome
Suppression of autocorrelation artifacts in PS-OCT images based on spectral phase interpolation
Polarization-maintaining (PM) fiber-based polarization-sensitive optical coherence tomography (PS-OCT) system has high stability and portability. However, PM fibers may introduce different kinds of artifacts. A spectral phase interpolation method is proposed to suppress the autocorrelation artifacts in this Letter, in which the reference phase is calculated based on each A-scan signal, and the calculated reference phase is used to perform phase interpolation in the original interference signal. Experimental results from the ex vivo porcine eye demonstrate that autocorrelation artifacts in PS-OCT images can be effectively eliminated and the original image information is perfectly recovered at artifacts.
Modeling of CO2 solubility and partial pressure in blended diisopropanolamine and 2-amino-2-methylpropanol solutions via response surface methodology and artificial neural network
Field-free ultrafast magnetization reversal of a nanodevice by a chirped current pulse via spin-orbit torque
We investigate the magnetization reversal of a perpendicularly magnetized nanodevice using a chirped current pulse (CCP) via spin-orbit torques (SOTs). Our numerically simulated findings demonstrate that both the field-like (FL) and damping-like (DL) components of SOT in CCP can be efficiently utilized to induce ultrafast magnetization reversal without any symmetry-breaking means. For a wide frequency range of the CCP, the minimal current density is significantly smaller compared to the current density of conventional SOT-reversal. This ultrafast reversal is achieved due to the CCP triggering enhanced energy absorption (emission) of the magnetization from (to) the FL- and DL-components of SOT before (after) crossing over the energy barrier. We also verify the robustness of the CCP-driven magnetization reversal at room temperature. Moreover, this strategy is applicable also to induce field-free ultrafast and efficient switching of perpendicular synthetic antiferromagnetic and ferrimagnetic (SFi) nanodevices. The minimal current density of deterministic switching of the SFi system decreases significantly with the reduction of one layer's magnetization, mainly because the SOT amplitude is inversely proportional to the saturation magnetization. Therefore, this study enriches the basic understanding of field-free SOT-reversal and provides a way to realize ultrafast SOT-MRAM devices with various free layer designs.
Dietary Chia (Salvia hispanica L.) seeds oil supplementation augments growth performance and gut microbial composition in Labeo rohita fingerlings
Non-monotonic fluctuation of structural heterogeneity in metallic glass due to cyclic rapid heat treatment
Flash-annealing (FA) of metallic glasses (MGs) allows one to modulate their disordered structure. Here, we have flash-annealed a CuZr-based MG below the glass transition temperature at different cycles and generated MGs with various heterogeneous structures. We quantified the glassy structure via the relaxation enthalpy, ΔrelH, which did not significantly change for MGs flash-annealed at a low number of cycles. Their hardness monotonically reduced. However, when more than ten FA cycles were applied, ΔrelH, perceivably decreased, while corresponding hardness increased. High-energy x-ray diffraction analysis revealed that the medium-range ordering of the corresponding structure initially rose and then decreased with an increasing number of FA cycles. This structural change is accompanied by first a hardness decrease followed by an increase. Molecular dynamics simulations showed that throughout the shift from low to high cycles, the structural non-uniformity changed from being non-uniform to more uniform. Through a combination of experiments and simulations, we have shown the non-monotonic relationship between the structural heterogeneity of MGs and cyclic treatments, contributing to a better understanding of the relationship between structural control techniques, microstructure, and properties.
Action inflexibility and compulsive-like behavior accompany neurobiological alterations in the anterior orbitofrontal cortex and associated striatal nuclei
Quantum mode-locked Faraday laser
We report an external-cavity mode-locked semiconductor laser that uses a Faraday atomic filter as a saturable absorber (SA), termed as the quantum mode-locked Faraday laser. The unique SA exhibits nonlinear transmission characteristics exclusively in the vicinity of the atomic quantum transition frequency, which narrows down the spectral bandwidth of the mode-locked pulses to the gigahertz level and results in a central wavelength of the mode-locked pulses corresponding to the 87Rb (F=2) component of the D2 quantum transition line. Simultaneously, influenced by the slow-light effect of rubidium-dispersive vapor in the SA configuration, the fundamental repetition rate of the mode locking can vary between 261 and 228 MHz. Pulse delay tests conducted outside the resonator provide conclusive evidence of a gigahertz-bandwidth slow light within the Faraday laser. The mode-locking technique presented here can be applied to pulsed light sources of other quantum transition lines by setting appropriate atomic filter parameters. In addition, this narrow-spectrum mode-locked laser, with a tunable repetition rate and a central wavelength corresponding to a quantum transition line, has potential applications in the fields of atomic precision spectroscopy and quantum precision metrology.
Development of a model for detection and analysis of inclusions in tomographic images of iron castings using decision trees
High-strength elastomer separator for high-current-density-charging lithium metal batteries
Utilizing lithium metal as an anode in batteries has been expected to replace conventional lithium-ion batteries. However, the mechanical properties and electrochemical performance of current separators do not meet the requirements for practical applications of lithium metal batteries (LMBs). Here, we report an elastomer separator with an interconnected structure of plastic-crystal-embedded and garnet-conductor-regulated thermoplastic polystyrene-b-poly(ethylene-r-butylene)-b-polystyrene elastomer integrated with the polyethylene matrix. The 14-micron-thick elastomer separators show a combination of excellent elongation of ∼115.2% and sufficiently high tensile strength of ∼56 MPa. The elastomer separators accommodate volume changes and block dendrites for high-current-density cycling of LMBs. As a demonstration, the elastomer separators enable stable operation of LMBs under stringent conditions, a practical high loading of 18 mg cm−2 LiNi0.8Co0.1Mn0.1O2 (NCM811) cathode at an extremely high charging/discharging current density of 1.8 mA cm−2, delivering a high reversible capacity of 164 mAh g−1 and capacity retention of 88% after 140 cycles.
Purification of arsenic-contaminated drinking water by Fe-Al-CO3 layered double hydroxide derived from secondary aluminum dross: adsorption and stabilization studies
Spin transfer torque switching in double magnetic tunnel junctions based on dual MgO layers
We report fabrication and characterization of double magnetic tunnel junction (DMTJ) magneto-resistive random access memory cells that exhibit characteristic about 2X reduction of switching current compared to single reference layer junctions, but maintain high tunneling magnetoresistance ratio exceeding 120 %, high coercive fields of the free layer of more than 2 kOe for 65 nm cells, and magnetically stable reference layers with pinning fields above 6 kOe. Switching analysis performed for two different relative magnetization orientations of the reference layers shows that the net switching current is the result of combined spin transfer torque effects of the individual reference layers, with tunneling and spin-valve-like contributions adding constructively. Our work shows that efficient reduction of switching current can be achieved in double magnetic tunnel junctions with dual MgO layers where one of the layers has significantly lower resistance-area product to enable high magnetoresistance ratio.
Bending behavior and influence parameter optimization of connection joints of disc-buckle type formwork support
Multi-functional terahertz nano-metasurface for beam-splitting and nonlinear resonance frequency shifting
The emergence of terahertz (THz) nanoscale resonance metasurface devices represents an innovative method for modulating THz waves by utilizing the intense, high-frequency alternating electric field in THz radiation. However, compared to traditional modulation methods that employ electrical, optical, and other techniques, the potential of these devices still necessitates further exploration. In this work, we achieved THz beam-splitting and field-induced nonlinear frequency shifting functions within a single THz nano-metasurface device. The device consists of single split-ring resonators (s-SRRs) with a nanogap on GaAs substrate. The pattern design based on the Pancharatnam–Berry (P-B) phase principle can split the incident wave into three beams. Meanwhile, its frequency shifting capability, which varies with the E-field, has been thoroughly investigated. The device performance was experimentally evaluated by an angle-resolved THz time-domain spectroscopy (THz-TDS) system and a strong-field THz-TDS system. This device could serve as a promising research platform for integrating THz with nano-optics and holds the potential for ultrafast modulation, offering application prospects in radar, wireless communication, and electromagnetic protection.
High throughput method for simultaneous screening of membrane permeability and toxicity for discovery of new cryoprotective agents
Enhanced perovskite crystallinity via short-term ultraviolet irradiation
Despite the recent rapid development in the organic–inorganic halide perovskite solar cells (PSCs), the crystalline stability of the perovskite (PVK) material, particularly of the MAPbI3, remains a significant impediment to PSC applications. We proposed that short-term ultraviolet (UV) irradiation under air conditions can stabilize the PVK phase and increases the film crystallinity. Detailed investigations indicated that the electrons can be released from the bridging hydroxyls (OHB) bonds under UV irradiation to generate a small amount of active oxygen (O2−) on the TiO2 film surface, forming stable Pb–O bonds and α phase PVK. A 25% increases in photovoltaic conversion efficiency with a considerable stability, and the device maintains over 90% efficiency after 400 h of storage in N2. This study provides a simple and effective method to produce efficient and stable PSC devices at low cost.
Research on spatial prediction technology for mitigating tunnel inrush disasters under complex geological conditions in China’s Hengduan Mountain Range
Boosting thermoelectric properties of n-type PbS across a broad temperature range through doping with trace amounts of InBi
Lead sulfide (PbS) is a promising thermoelectric material due to its high availability, thermal stability, and cost-efficiency, with research predominantly aiming to enhance its carrier concentration through heavy doping for optimal ZT values at high temperatures. However, this approach often results in suboptimal performance at ambient temperature, significantly constraining its applicability in thermoelectric cooling technologies. In this work, the carrier concentration of n-type PbS is optimized by incorporating trace amounts of InBi. Due to the low carrier concentration, PbS retains a high Seebeck coefficient and carrier mobility, resulting in a high average power factor (PFave) of 15.4 μW·cm−1·K−2 within the temperature range from 300 to 773 K. In addition, the introduction of In/Bi interstitial atoms and dislocation defects enhances phonon scattering, effectively reducing the lattice thermal conductivity of PbS. The peak ZT value of Pb0.999(InBi)0.001S at 773 K reaches ∼1.0, while an average ZT value (ZTave) of ∼0.6 is achieved between 300 and 773 K in Pb0.9995(InBi)0.0005S. This study demonstrates that trace element doping is an effective strategy for optimizing the thermoelectric performance of PbS across a wide temperature range, which is vital in the thermoelectric power generation and refrigeration application.