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Improving the performance of solar cells by optimizing the interface of SnO2/perovskite layer using sodium citrate
Interface engineering is an important means of modifying perovskite solar cells (PSCs). In this paper, a strategy for modifying the SnO2/perovskite interface transport layer using sodium citrate (SC), an organic sodium salt, was proposed. The optimal power conversion efficiency was 22.55%, 9.3% higher than that of devices without SC modification. The open circuit voltage (Voc) reaches a respectable 1.20 V. This method enhances the conductivity of thin SnO2 films with inert photocatalytic performance, improves the crystallinity of perovskite, and increases the grain size, thereby meliorating the performance and stability of PSCs.
Early life stress, kangaroo care, parenting behavior and secure attachment predict executive functioning in 2 year olds born preterm
Thermal conductivity of AlN thin films deposited by reactive DC magnetron sputtering on different substrates using ultra-fast transient hot strip technique
In the frame of this work, we report a profound insight into the thermal conductivity (k) of aluminum nitride (AlN) thin films deposited on AlN-molecular beam epitaxy (MBE)/Si(111) and AlN-Kyma/Si(111) substrates at low temperatures (<200 °C) using reactive direct current magnetron sputtering (DCMS). Our concern is not on the thermal properties at the nanoscale, but rather on relating thermal macroscopic properties to the microstructure for submicronic to micronic AlN films. As the mean free path for AlN material is about 100 nm, the thickness of our films lies between 400 nm and 2 μm. The k measurements were conducted using the ultra-fast transient hot strip technique. It was found that the k values of the deposited films change depending on both the substrate type and the film thickness. For the 500 nm AlN thick film, k value was about 250 W m−1 K−1 for AlN-DCMS films grown on 10 nm AlN-MBE/Si against 90 W m−1 K−1 for those deposited on 200 nm AlN-Kyma/Si. The thermal boundary resistance has been computed equal to (0.25 ± 0.08) × 10−9 K m2 W−1 on 10 nm AlN-MBE/Si against (3.56 ± 1.50) × 10−9 K m2 W−1 on 200 nm AlN-Kyma/Si. Additionally, both pole figures and high resolution transmission electron microscopy confirm k results. In fact, pole figures confirm the good crystal quality of the film on both substrates, but HR-TEM analyses show that the AlN films grown on 10 nm AlN-MBE/Si template exhibit good crystalline quality with an epitaxial regrowth and abrupt interface compared to those obtained for 200 nm AlN-Kyma/Si. It also appears that the thermal boundary resistance plays a major role in the thermal properties of AlN films.
Comparative effective dose of ciprofol and propofol in suppressing cardiovascular responses to tracheal intubation
Abstract Ciprofol, a novel γ-aminobutyric acid receptor agonist, outperforms propofol with minimal cardiovascular effects, higher potency, reduced injection pain, and a broader safety margin. Despite these advantages, ciprofol’s clinical research is still emerging. This study compares the median effective dose (ED 50 ) and adverse reactions of ciprofol and propofol, in conjunction with sufentanil, for suppressing cardiovascular responses during tracheal intubation. Fifty-three adult patients scheduled for tracheal intubation under general anesthesia were enrolled and randomly assigned to receive either ciprofol (Group C) or propofol (Group P), according to a random number table. Tracheal intubation was performed using a standardized laryngoscope and endotracheal tube. The Dixon’s up-and-down method was employed to determine the ED 50 and 95% effective dose (ED 95 ) of ciprofol and propofol in inhibiting cardiovascular responses during tracheal intubation. Based on the pilot study, the initial dose for ciprofol was set at 0.35 mg/kg (with a 0.01 mg/kg increment) and for propofol at 2.0 mg/kg (with a 0.1 mg/kg increment). Probit analysis was applied to derive dose-response curves, while adverse reactions were continuously monitored. A total of 54 participants were included, with 24 in group C (1 excluded) and 30 in group P. Probit analysis revealed that the ED 50 of ciprofol for inhibiting cardiovascular responses to tracheal intubation were 0.326 mg/kg (95% CI 0.304–0.337 mg/kg), and for propofol, 1.541 mg/kg (95% CI 1.481–1.599 mg/kg). The heart rate in group P was significantly higher than the group C at 1 minute ( p = 0.026) and 3 minutes ( p = 0.016) post-intubation. Systolic and diastolic blood pressures (SBP and DBP) decreased significantly before and after intubation compared to baseline values in both groups ( p < 0.05). Group C experienced significantly less injection pain ( p = 0.001), although the incidence of other adverse effects was not statistically different between groups ( p > 0.05). Clinical Trial Registration : hppts://ClinicalTrials.gov; Identifier: NCT06095570(18/10/2023).
Self-powered ultraviolet position-sensitive detectors based on PrNiO3/Nb-doped SrTiO3 p–n junctions
Position-sensitive detectors based on the lateral photovoltaic effect have been widely used in optical engineering for the measurement of position, distance, and angles. However, self-powered ultraviolet position-sensitive detectors with high sensitivity and fast response are still lacking due to the difficulty associated with the fabrication of p-type wide bandgap semiconductors, which hinders their further design and enhancement. Here, the influence of band structures and interfacial transport properties on the performance of self-powered ultraviolet position-sensitive detectors based on PrNiO3/Nb:SrTiO3p–n junctions is systematically investigated. Large position sensitivity and fast relaxation time of the lateral photovoltaic effect were observed up to 400 K in the perovskite-based ultraviolet position-sensitive detectors. Hall effect measurements revealed that the transport of photoexcited carriers occurs mainly through the interface of the PrNiO3/Nb:SrTiO3 junctions, resulting in a fast response and a stable photovoltaic effect. This study presents insights and avenues for designing self-powered perovskite oxide ultraviolet position-sensitive detectors with enhanced photoelectric performance.
Nematode controlling effects and safety tests of Duddingtonia flagrans biological preparation in sheep
High mobility crystallized stacked-channel thin-film transistors induced by low-temperature thermal annealing
A high mobility crystallized stacked-channel thin-film transistor (TFT) was fabricated and characterized. The stacked IGO/IGZO channel film consisting of an In-rich IGO layer and a conventional IGZO layer was fabricated by atomic layer deposition technology, where the upper layer of amorphous IGZO is induced into nanocrystals by the lower layer of preferentially oriented polycrystalline IGO during thermal annealing at a low temperature of 300 °C. The preferential growth of nanocrystalline IGZO with matched crystal structure in the channel favors the transport of electrons. In addition, the accumulation of a large number of electrons at the heterojunction due to energy band bending provides a strong guarantee for high mobility. The crystallized stacked IGO/IGZO TFT exhibits a superior field effect mobility of 95.7 cm2 V−1 s−1, which is 55.9% higher than that of single-layer IGO TFT. At the same time, the stability of the device was also dramatically improved. The proposed strategy is a simple and promising approach to prepare high performance TFTs for future display and semiconductor applications.
Uniform impact on individual megakaryocytes is essential for efficient in vitro platelet production
Size effect on Raman measured stress and strain induced phonon shifts in ultra-thin silicon film
The fabrication of complex nano-scale structures, which is a crucial step in the scaling of (nano)electronic devices, often leads to residual stress in the different layers present. This stress gradient can change many of the material properties, leading to changes in device performance, especially in the active part of the transistor, the channel. Measuring, understanding, and, ultimately, controlling the stress fields is hence crucial for many design steps. The level of stress can in principle be measured by micro-Raman spectroscopy. This, however, requires a priori knowledge of the mechanical properties of the material. However, mechanical properties start to deviate from the bulk values when film dimensions become thinner than 5 nm. If this effect is ignored, errors of up to 400% can be introduced in the extracted stress profile. In this work, we illustrate this effect for a range of Si (001) slabs with different silicon film thicknesses, ranging from 5 to 0.7 nm and provide best practices for the proper interpretation of micro-Raman stress measurements.
Transcription factor FOXD1 and miRNA-204-5p play a major role in B4GALNT2 downregulation in colon cancer
Lowering the skyrmion depinning current in synthetic antiferromagnetic systems
Magnetic skyrmions, as topological spin textures, offer great potential for next-generation spintronic applications. Skyrmions in artificially synthesized antiferromagnets (SAFs) are particularly promising due to their ability to suppress the skyrmion Hall effect and achieve faster dynamics, making them highly attractive for spintronic devices. However, the critical current density required to drive SAF skyrmions using spin-transfer torque is significantly higher than in conventional ferromagnetic systems. In this work, we analytically and numerically demonstrate that the critical current density for SAF skyrmions can be significantly reduced by applying distinct currents to different layers within the system. This approach can be applied to periodically pinned skyrmions in SAFs, offering the dual benefits of a suppressed Hall effect and a reduced critical current density. Our findings pave the way for more efficient manipulation of SAF skyrmions in spintronic device architectures.
Attenuation of progressive surface gravity waves by floating spheres
High-temperature performance of metal/n-Ga2O3/p-diamond heterojunction diode fabricated by ALD method
A metal/n-Ga2O3/p-diamond heterojunction diode with superior high-temperature performance was demonstrated in this work. The p-type diamond was lightly boron doped, and the Ga2O3 film was grown via atomic layer deposition without intentional doping. The forward current density increased with temperature, while the reverse current decreased at elevated temperatures. This behavior was attributed to the distinct carrier ionization dynamics across varying temperature ranges. Under high reverse voltage stress, the reverse current remained relatively stable, with no breakdown occurring up to 498 K. An avalanche breakdown voltage of 186 V at 498 K indicates the diode's robust high-voltage endurance capability. These findings underscore the potential of the metal/n-Ga2O3/p-diamond heterojunction diode for high-temperature and high-voltage applications.
The role of impulsivity and emotional dysregulation in smartphone overdependence explored through network analysis
Synergistic physical and chemical effects of MOF-derived porous Fe3C–NC to boost the performance of Li–S batteries
Lithium–sulfur (Li–S) batteries are one of the key objects of next-generation energy storage systems due to their high energy density and low-cost characteristics. However, the slow reaction kinetics and serious shuttle effect of lithium polysulfides (LiPSs) have hindered their practical application. In this work, metal-organic framework-derived Fe3C decorated nitrogen-doped carbon matrix (Fe3C–NC) composites were prepared to modify the separator to promote the reaction kinetics of Li–S batteries. The porous and conductive NC facilitates the trapping of LiPSs, rapid transfer of charge, and alleviated volume expansion, while the Fe3C–NC with optimum Fe3C content can significantly reduce the energy barrier of the electrochemical conversion reaction, accelerate the transport of lithium ions, and enhance the reaction kinetics of LiPSs, which are conducive to inhibit the shuttle effect through synergistic physical and chemical interactions. The Li–S battery with Fe3C–NC separator exhibits excellent cycle stability with an initial discharge specific capacity of 1099.19 mAh g−1 at 1 C and a low-capacity decay of 0.068% per cycle over 500 cycles. Even at a high S loading of 5.93 mg cm−2, it still delivers reliable cyclic stability with an initial discharge specific capacity of 903.65 mAh g−1 at 0.1 C. This work provides a convenient and effective method for the application of metallic materials combined with nitrogen-doped carbon matrix in high-performance Li–S batteries.
Green synthesized FeNPs ameliorate drought stress in Spinacia oleracea L. through improved photosynthetic capacity, redox balance, and antioxidant defense
Spin injection and detection using perpendicularly magnetized Mn/Co bilayers grown on GaAs via all electrical methods
The electrical spin injection and detection in perpendicularly magnetized Mn/Co/n-GaAs junction was investigated using a non-local method. Clear non-local spin-valve signals and Hanle effect signals were observed at 77 K, providing direct evidence of the injection and detection of perpendicularly polarized spins through all electrical methods. The magnitude of the spin-valve signal was one order of magnitude smaller than that observed in a reference sample with an in-plane magnetized CoFe due to the low spin polarization of the ultrathin Mn/Co electrodes. It was found that the spin polarization at the interface between Mn/Co electrode and n+-GaAs had a relatively weak bias-current dependence in contrast to that at CoFe/n+-GaAs interface. The estimated spin lifetime of perpendicular spins injected from the Mn/Co bilayer into n-GaAs was approximately 1.9 ns at 77 K. This value is similar to that of in-plane spins injected from CoFe, indicating that the spin lifetime was not strongly dependent on the spin orientation in the bulk GaAs channel.
Biocompatible autonomous self-healing PVA-CS/TA hydrogels based on hydrogen bonding and electrostatic interaction
First-principles study on electronic and optical properties of perovskite light-emitting diodes CsPb(Br1<b>−</b> <i>x</i>I<i>x</i>)3
CsPb(Br1−xIx)3, a mixed-halide all-inorganic perovskite, is a promising light-emitting diode (LED) material due to its impressive performance. It has been demonstrated that the mixing parameter x of halogen composition significantly influences the luminescence efficiency of CsPb(Br1−xIx)3. However, the underlying microscopic mechanisms remain unclear. Using first-principles calculations, we investigate the effects of anion mixing on the radiative and non-radiative recombination properties of perovskite materials. Simulations on the carrier mobility, exciton binding energy, affinity energy, and defect formation energy of the materials in the CsPb(Br1−xIx)3 system collaboratively revealed that a high ratio off Br is associated with enhanced luminescence efficiency. Specifically, CsPb(Br1−xIx)3 exhibits optimal luminescent performance with a 2:1 bromine-to-iodine ratio, while it shows the performance degradation with a 1:1 ratio. The results demonstrate that the ratio of halogen atoms (Br and I) has a significant influence on the LED properties of cesium-based all-inorganic perovskites CsPb(Br1−xIx)3, providing a valuable guide for the experimental preparation of cesium-based all-inorganic perovskites.