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This work presents a 2D tellurium (Te)‐based diode that exploits the doping achieved by atomic layer deposited (ALD) Al2O3 to enhance its rectifying performance. The proposed device comprises a Schottky junction that is dielectric‐doped to significantly reduce the reverse bias current. A boosted current responsivity four times higher compared to that of undoped devices is achieved, maximizing the performance for radio frequency (RF) power detectors. The application measurement results demonstrate sensitivities as low as −45 dBm, and at −30 dBm RF input power outstanding tangential responsivities up to 6.5 kV W–1, 4.3 kV W–1, and 650 V W–1 at 0.5, 1, and 2.5 GHz, respectively, while reaching linear dynamic range (DR) of over 30 dB. These are the highest reported values for 2D‐based material devices by almost two orders of magnitude. Furthermore, the DR is ≈10 dB larger compared to state‐of‐the‐art power detectors based on bulk semiconductors. [ABSTRACT FROM AUTHOR]

In this paper, we investigate various graphene monolayer nanomesh structures (diodes) formed only by nanoholes, with a diameter of just 20 nm and etched from the graphene layer in different shapes (such as rhombus, bow tie, rectangle, trapezoid, and triangle), and their electrical properties targeting electromagnetic energy harvesting applications. In this respect, the main parameters characterizing any nonlinear device for energy harvesting are extracted from tens of measurements performed on a single chip containing the fabricated diodes. The best nano-perforated graphene structure is the triangle nanomesh structure, which exhibits remarkable performance in terms of its characteristic parameters, e.g., a 420 Ω differential resistance for optimal impedance matching to an antenna, a high responsivity greater than 103 V/W, and a low noise equivalent power of 847 pW/√Hz at 0 V. [ABSTRACT FROM AUTHOR]

Materials with tunable properties are often in the focus of materials science. Up to this point four different semiconducting materials and substitution variants have been found that are capable of switching between p‐ and n‐type conduction by a simple change in temperature. In this review, we illustrate previous findings of these pnp‐switching materials and current developments in functional implementations. While in the past decade, the scientific focus was primarily on discovering new materials that possess this intriguing switching effect, recently the first devices were successfully constructed and tested. Using the compounds, Ag18Cu3Te11Cl3 and AgCuS, that exhibit the pnp‐switching behaviour at approximately room temperature and 364 K, respectively, two single‐material diodes were developed and characterized. The approach for inducing this effect is denoted and the fundamental principles for realizing these devices are summarized. [ABSTRACT FROM AUTHOR]

Background: Ultra‐high‐dose‐rate (UHDR) electron beams have been commonly utilized in FLASH studies and the translation of FLASH Radiotherapy (RT) to the clinic. The EDGE diode detector has potential use for UHDR dosimetry albeit with a beam energy dependency observed. Purpose: The purpose is to present the electron beam response for an EDGE detector in dependence on beam energy, to characterize the EDGE detector's response under UHDR conditions, and to validate correction factors derived from the first detailed Monte Carlo model of the EDGE diode against measurements, particularly under UHDR conditions. Methods: Percentage depth doses (PDDs) for the UHDR Mobetron were measured with both EDGE detectors and films. A detailed Monte Carlo (MC) model of the EDGE detector has been configured according to the blueprint provided by the manufacturer under an NDA agreement. Water/silicon dose ratios of EDGE detector for a series of mono‐energetic electron beams have been calculated. The dependence of the water/silicon dose ratio on depth for a FLASH relevant electron beam was also studied. An analytical approach for the correction of PDD measured with EDGE detectors was established. Results: Water/silicon dose ratio decreased with decreasing electron beam energy. For the Mobetron 9 MeV UHDR electron beam, the ratio decreased from 1.09 to 1.03 in the build‐up region, maintained in range of 0.98–1.02 at the fall‐off region and raised to a plateau in value of 1.08 at the tail. By applying the corrections, good agreement between the PDDs measured by the EDGE detector and those measured with film was achieved. Conclusions: Electron beam response of an UHDR capable EDGE detector was derived from first principles utilizing a sophisticated MC model. An analytical approach was validated for the PDDs of UHDR electron beams. The results demonstrated the capability of EDGE detector in measuring PDDs of UHDR electron beams. [ABSTRACT FROM AUTHOR]

The study investigates high-voltage gradual p0–i–n0 junctions in solid solutions of AlxGa1 – xAs1 – ySby with y up to 15%, which are capable of absorbing radiation with a wavelength of 1064 nm, grown on GaAs substrates by liquid-phase epitaxy through self-doping with background impurities. The composition of the liquid phase and the temperature range of growth are selected so that the aluminum-compound content x decreased steadily from the specified values of about 34% to a few percent at the surface of the epitaxial layer, while the antimony-compound content y increased. In this case, the band-gap width gradually decreased from the substrate to the surface of the lightly doped layer, reaching the desired value of ~1.16 eV. By measuring the capacity–voltage characteristics and deep level transient spectroscopy in them, configurationally bistable DX centers associated with donor impurities Si and Se/Te are identified. The investigated heterophase epitaxial layers reveal the absence of deep energy levels associated with dislocations. The effective lifetime of minority charge carriers in the base layers of the AlxGa1 – xAs1 – ySby/GaAs diode is determined using reverse recovery of the diode. Assuming that the minority-carrier lifetime is mainly determined by the capture of holes by the acceptor-like deep level DX – of Si in the n0 layer of the material, the hole capture cross section on the DX – level is estimated. The capture cross section is found to be 6 × 10–15 cm2. [ABSTRACT FROM AUTHOR]

We present here the fabrication at the wafer level and the electrical performance of two types of graphene diodes: ballistic trapezoidal-shaped graphene diodes and lateral tunneling graphene diodes. In the case of the ballistic trapezoidal-shaped graphene diode, we observe a large DC current of 200 µA at a DC bias voltage of ±2 V and a large voltage responsivity of 2000 v/w, while in the case of the lateral tunneling graphene diodes, we obtain a DC current of 1.5 mA at a DC bias voltage of ±2 V, with a voltage responsivity of 3000 v/w. An extended analysis of the defects produced during the fabrication process and their influences on the graphene diode performance is also presented. [ABSTRACT FROM AUTHOR]

In‐memory computing significantly reduces workload and energy cost of data access in the traditional von Neumann computing architecture. Using various memristors, stateful logic is developed to realize in‐memory computing. However, memristors have encountered critical issues in terms of device variation and reliability, and therefore, fundamental device solutions are required to realize practical stateful logic. In this study, NAND, NOR, and half‐adder stateful logic operations of gated silicon diodes with a p+–n–p–n+ structure are demonstrated to achieve in‐memory computing. Gated diodes have bistable, steep switching, and quasi‐nonvolatile memory characteristics, enabling reliable stateful logic operation. The uniformity of their device characteristics overcomes the inherent stochastic characteristics of memristors that are widely researched for stateful logic. The sequential multiread logic operation simplifies the complex state logic scheme. In particular, a nondestructive half‐adder operation can be executed in five sequential steps using six parallel diodes. Thus, the stateful logic of gated diodes can be a potential building block for in‐memory computing. [ABSTRACT FROM AUTHOR]

A simple yet effective method for fabricating heterojunction diodes is presented in this study. It involves the deposition of Ni1-xCoxO thin films on n-Si substrates, taken in the stoichiometric ratio. Experiments have been carried out to investigate the electrical behavior of the diodes by varying the mixing ratios of CoO and NiO. The effect of the various stoichiometric ratio of CoO and NiO on the optical and electrical properties of the films was analyzed using UV-vis absorption spectra and two-probe resistivity measurements. The electrical properties of Ag/Ni1-xCoxO/n-Si diodes were found to be significantly affected by changes in the concentration of cobalt oxide and nickel oxide. All diodes exhibited rectification behavior as evidenced by their dark I-V characteristics. Important junction parameters such as the series resistance (Rs), the rectification ratio (RR), the ideality factor (n), and the barrier height (ΦB) were calculated by analyzing the I-V data. In addition, the capacitance-voltage (C-V) characteristics were measured over a frequency range from 10 kHz to 1 MHz. Our results show that the electrical properties of the Ag/Ni1-xCoxO/n-Si diodes can be tuned by varying the concentration ratios of cobalt oxide and nickel oxide. [ABSTRACT FROM AUTHOR]

This work presents the green synthesis of iron oxide nanoparticles (IONPs) using Baccharis salicifolia extract and their incorporation in mesoporous silica MCM-41, obtaining an MCM-41@IONP composite. The MCM-41@IONP composite was characterized by X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), nitrogen adsorption and desorption, scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS). The use of the natural reducing agent Baccharis salicifolia resulted in nanoparticles with an average size of 31 nm. Furthermore, we showcase the application of the MCM-41@IONP nanocomposite in a metal–insulator–semiconductor (MIS) diode, which was fabricated at room temperature. The current–voltage and capacitance–voltage curves of the MIS diode were carefully measured and subjected to detailed analysis. The results demonstrate the potential utility of MCM-41@IONP nanocomposite-based MIS diodes, suggesting their applicability in the design of biosensors or as discrete components in electronic devices. [ABSTRACT FROM AUTHOR]

Abstract This work presents a 2D tellurium (Te)‐based diode that exploits the doping achieved by atomic layer deposited (ALD) Al2O3 to enhance its rectifying performance. The proposed device comprises a Schottky junction that is dielectric‐doped to significantly reduce the reverse bias current. A boosted current responsivity four times higher compared to that of undoped devices is achieved, maximizing the performance for radio frequency (RF) power detectors. The application measurement results demonstrate sensitivities as low as −45 dBm, and at −30 dBm RF input power outstanding tangential responsivities up to 6.5 kV W–1, 4.3 kV W–1, and 650 V W–1 at 0.5, 1, and 2.5 GHz, respectively, while reaching linear dynamic range (DR) of over 30 dB. These are the highest reported values for 2D‐based material devices by almost two orders of magnitude. Furthermore, the DR is ≈10 dB larger compared to state‐of‐the‐art power detectors based on bulk semiconductors.

Abstract The potential of skyrmions as information carriers in spintronic devices has garnered significant attention. In this paper, the study investigates the current driven movement behavior of skyrmions in elliptical‐ring tracks (ERTs). The findings suggest that the curvature gradient of ERTs can either increase or decrease skyrmion velocity. The increase in velocity aids in transmitting skyrmions, while the decrease in velocity helps in intercepting them. Based on the transmission and interception of skyrmion controlled by the curvature gradient of the ERT, the study has designed diode, logic NOT, AND, and OR gates. The feasibility and robustness of these devices are demonstrated through micromagnetic simulations. The research provides valuable insights and recommendations for designing skyrmion‐based devices with curved geometries.

This work presents the green synthesis of iron oxide nanoparticles (IONPs) using Baccharis salicifolia extract and their incorporation in mesoporous silica MCM-41, obtaining an MCM-41@IONP composite. The MCM-41@IONP composite was characterized by X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), nitrogen adsorption and desorption, scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS). The use of the natural reducing agent Baccharis salicifolia resulted in nanoparticles with an average size of 31 nm. Furthermore, we showcase the application of the MCM-41@IONP nanocomposite in a metal–insulator–semiconductor (MIS) diode, which was fabricated at room temperature. The current–voltage and capacitance–voltage curves of the MIS diode were carefully measured and subjected to detailed analysis. The results demonstrate the potential utility of MCM-41@IONP nanocomposite-based MIS diodes, suggesting their applicability in the design of biosensors or as discrete components in electronic devices.

Highlights Engineering MXene into electrospun nanofibers can effectively enhance its thermal emissivity and conductance, and the unidirectional water transport of the wettability-gradient-induced-diode (WGID) membrane displayed diode-like properties with wettability gradient by tailoring the water contact angle of each single layer. The WGID membrane could achieve a cooling temperature of 1.5 °C in the “dry” state, and 7.1 °C in the “wet” state, with high emissivity of 96.40% in the MIR range, superior thermal conductivity of 0.3349 W m−1 K−1. Zero-energy-consumption for personal cooling management via multiple heat dissipation pathways, including thermal radiation, conduction, and evaporation.

This study involved direct doping of In2O3 into silicon carbide (SiC) powder, resulting in 8.0 at% In-doped SiC powder. Subsequently, heating at 500 °C was performed to form a target, followed by the utilization of electron beam (e-beam) technology to deposit the In-doped SiC thin films with the thickness of approximately 189.8 nm. The first breakthrough of this research was the successful deposition of using e-beam technology. The second breakthrough involved utilizing various tools to analyze the physical and electrical properties of In-doped SiC thin films. Hall effect measurement was used to measure the resistivity, mobility, and carrier concentration and confirm its n-type semiconductor nature. The uniform dispersion of In ions in SiC was as confirmed by electron microscopy energy-dispersive spectroscopy and secondary ion mass spectrometry analyses. The Tauc Plot method was employed to determine the Eg values of pure SiC and In-doped SiC thin films. Semiconductor parameter analyzer was used to measure the conductivity and the I-V characteristics of devices in In-doped SiC thin films. Furthermore, the third finding demonstrated that In2O3-doped SiC thin films exhibited remarkable current density. X-ray photoelectron spectroscopy and Gaussian-resolved spectra further confirmed a significant relationship between conductivity and oxygen vacancy concentration. Lastly, depositing these In-doped SiC thin films onto p-type silicon substrates etched with buffered oxide etchant resulted in the formation of heterojunction p-n junction. This junction exhibited the rectifying characteristics of a diode, with sample current values in the vicinity of 102 mA, breakdown voltage at approximately −5.23 V, and open-circuit voltage around 1.56 V. This underscores the potential of In-doped SiC thin films for various semiconductor devices. [ABSTRACT FROM AUTHOR]

The electrical characterization and ammonia vapor (NH3) response of a p‐Si/n‐poly[benzimidazobenzophenanthroline] (n‐BBL) thin‐film junction diode are reported. The presence of a depletion layer at the n‐BBL/p‐Si interface is verified via capacitance–voltage measurements, and the built‐in potential is ≈1.8 V. Using the standard diode equation for data analysis, the turn‐on voltage, rectification ratio, and ideality parameter are found to be 2 V, 16, and 6, respectively. The diode is also tested in the presence of NH3 vapor where it retained its asymmetric J–V behavior with increased currents and an insignificant change in device parameters. NH3 is believed to interact with the adsorbed O2− species on the n‐BBL surface liberating electrons that enhance the diode current. The response time, recovery time, and sensitivity of the diode are 65 s, 121 s, and 52%, respectively. The removal of the gas restores the diode characteristics to their near original shape making it reusable. The diode is also electrically characterized as a function of temperature and is found to retain its rectifying behavior down to 150 K. The rectifying and gas‐sensing features make the diode multifunctional, which expands the range of applications of this ladder‐type conducting polymer. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate and compare the clinical efficacy of diode laser and ozone gas in the treatment of dentin hypersensitivity (DHS). One hundred thirty-two teeth from 44 patients with moderate DHS were randomized into 3 groups according to a split-mouth design. In the diode laser group, the operator irradiated the superficial dentin exposed with an 808-nm wavelength and incremental power from 0.2 to 0.6 W with a 20-second interval. In the ozone gas group, the operator applied a high dose of ozone (32 g/m3) for 30 seconds using a silicon cup. In the placebo group, no therapy was applied. The dentin sensitivity level was evaluated upon enrollment (T0), immediately after treatment (T1), 3 months post-treatment (T2), and 6 months post-treatment (T3) with a cold air blast challenge and tactile stimuli. The pain severity was quantified according to the visual analogue scale. The Wilcoxon signed rank test was used to scrutinize potential statistical disparities among the treatments. Statistical significance was predetermined at P <.05. A significant decrease of DHS was observed in the ozone gas group and the 'diode laser group immediately after treatment and after 3 and 6 months of the therapy. After 6 months from the therapy, the sensitivity values in the teeth treated with ozone gas remained statistically lower than those treated with diode lasers (P <.05). A laser diode and ozone gas are both efficient as dentin sensitivity treatment. Ozone maintains an invariable effectiveness after 6 months. [ABSTRACT FROM AUTHOR]

In this work, the growth of CdZnNiPO (CZNP) thin films on glass and p-Si substrates using the sol–gel spin coating method was successfully achieved. The structure, and morphology of the CZNP films were analyzed using XRD and FE-SEM. The optical absorbance behavior, energy gap, refractive indices, optical dielectric, optical conductivity, and optical electronegativity of the films were studied using the UV–Vis optical spectroscopy technique. XRD analysis shows that zinc phosphate accommodates cadmium ions by replacing zinc ions in the unit cell, resulting in oxygen vacancies that maintain charge neutrality. Scanning electron microscope images reveal the presence of a highly interconnected and well-organized nano CZNP framework. The optical absorption studies of CZNP films were conducted in the wavelength range of 190–2500 nm. The results show both direct and indirect energy band gaps of 1.69 and 2.89 eV, respectively, were employed in the prepared system. The current–voltage-temperature (I-V-T) characteristics of the CZNP/p-Si junction was analyzed in dark mode. The device transport ideality factor, barrier height, and series resistance were identified. [ABSTRACT FROM AUTHOR]

Highlights: Engineering MXene into electrospun nanofibers can effectively enhance its thermal emissivity and conductance, and the unidirectional water transport of the wettability-gradient-induced-diode (WGID) membrane displayed diode-like properties with wettability gradient by tailoring the water contact angle of each single layer. The WGID membrane could achieve a cooling temperature of 1.5 °C in the "dry" state, and 7.1 °C in the "wet" state, with high emissivity of 96.40% in the MIR range, superior thermal conductivity of 0.3349 W m−1 K−1. Zero-energy-consumption for personal cooling management via multiple heat dissipation pathways, including thermal radiation, conduction, and evaporation. Thermoregulatory textiles, leveraging high-emissivity structural materials, have arisen as a promising candidate for personal cooling management; however, their advancement has been hindered by the underperformed water moisture transportation capacity, which impacts on their thermophysiological comfort. Herein, we designed a wettability-gradient-induced-diode (WGID) membrane achieving by MXene-engineered electrospun technology, which could facilitate heat dissipation and moisture-wicking transportation. As a result, the obtained WGID membrane could obtain a cooling temperature of 1.5 °C in the "dry" state, and 7.1 °C in the "wet" state, which was ascribed to its high emissivity of 96.40% in the MIR range, superior thermal conductivity of 0.3349 W m−1 K−1 (based on radiation- and conduction-controlled mechanisms), and unidirectional moisture transportation property. The proposed design offers an approach for meticulously engineering electrospun membranes with enhanced heat dissipation and moisture transportation, thereby paving the way for developing more efficient and comfortable thermoregulatory textiles in a high-humidity microenvironment. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Medical Imaging & Radiation Sciences is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract In‐memory computing significantly reduces workload and energy cost of data access in the traditional von Neumann computing architecture. Using various memristors, stateful logic is developed to realize in‐memory computing. However, memristors have encountered critical issues in terms of device variation and reliability, and therefore, fundamental device solutions are required to realize practical stateful logic. In this study, NAND, NOR, and half‐adder stateful logic operations of gated silicon diodes with a p+–n–p–n+ structure are demonstrated to achieve in‐memory computing. Gated diodes have bistable, steep switching, and quasi‐nonvolatile memory characteristics, enabling reliable stateful logic operation. The uniformity of their device characteristics overcomes the inherent stochastic characteristics of memristors that are widely researched for stateful logic. The sequential multiread logic operation simplifies the complex state logic scheme. In particular, a nondestructive half‐adder operation can be executed in five sequential steps using six parallel diodes. Thus, the stateful logic of gated diodes can be a potential building block for in‐memory computing.

The miniaturized broadband detection module can be embedded into the microwave application system such as the front end of the transmitter to detect the power or other parameters in real time. It is highly prospective in military and scientific research. In this paper, a broadband power detection module operating at 26.5 ​GHz–40.0 ​GHz is designed by using low-barrier Schottky diode as the detector and a comparator for threshold output. This module can dynamically detect the power range between −10 ​dBm and 10 ​dBm with the detection accuracy of 0.1 ​dB. Further, the temperature compensation circuit is also applied to improve the measurement error. As a result, the resulted error low to ±1 ​dB in the temperature range of −55 ​°C to +85 ​°C is achieved. The designed module is encapsulated by a Kovar alloy with a small volume of 9 ​mm ​× ​6 ​mm ​× ​3 ​mm. This endows the designed module the advantages of small size, easy integration, and low cost, and even it is applicable to high-reliability environments such as satellites.

An improved EEHEMT nonlinear model with noise model has been developed in this paper. Empirical formulas of bias dependent noise model parameters are given. A four-stage 120–160 GHz monolithic low-noise amplifier (LNA) fabricated with the 70nm InAlAs/InGaAs/InP HEMT technology. The simulated results of S-parameters and noise figure show the good agreement with measured data to verify the accuracy of the proposed model.

The study focuses on analysing the high-level carrier lifetime ( $\tau _{\mathrm {HL}}$ ) in 4H silicon carbide (4H-SiC) PiN diodes under varying temperatures and proton implantation doses. The objective is to identify an empirical law applicable in technology computer-aided design (TCAD) modelling for SiC devices, describing the dependence of carrier lifetime on temperature to gain insights into how irradiation dose may influence the $\tau _{\mathrm {HL}}$ . We electrically characterize diodes of different diameters subjected to different proton irradiation doses and examine the variations in current-voltage (I-V) and ideality factor (n) curves under various irradiation conditions. The effects of proton irradiation on the epitaxial layer are analysed through capacitance-voltage (C-V) measurements. We correlate the observed effects on I-V, n, and C-V curves to the hypothesis of formation of acceptor-type defects related to carbon vacancies, specifically the Z $_{\mathrm {1/2}}$ defects generated during the irradiation process. The impact of irradiation on carrier lifetime is investigated by measuring $\tau _{\mathrm {HL}}$ using the open circuit voltage decay (OCVD) technique at different temperatures on diodes exposed to various H+ irradiation doses with constant ion energy. This investigation reveals the presence of a proportional relationship between 1/ $\tau _{\mathrm {HL}}$ and the dose of irradiated protons: the proportionality coefficient, referred to as the damage coefficient (K $_{\mathrm {T}}$ ), exhibits an Arrhenius-type dependence on temperature. OCVD-measured lifetime on the various diodes demonstrates a power-law dependence of lifetime on temperature. The exponent of this dependence varies with the irradiation dose, notably showing an increase in temperature dependence at the highest H+ ion dose. This suggests a threshold-like dependence on H+ irradiation dose in the $\tau _{\mathrm {HL}}$ -temperature relationship.

Capacitance-voltage (C-V) measurements play a crucial role in evaluating semiconductor device performance by revealing vital parameters such as doping levels and charge carrier behavior. This study specifically investigates the impact of mesa structures on C-V measurements in 4H-SiC PiN vertical diodes. Our analysis uncovers distinct capacitance values per unit area among diodes with varying diameters within the same diode family. These findings underscore the limitations of conventional capacitance equations formulated for planar devices when extended to mesa-structured devices. To separate the capacitance portion dependent solely on the PN junction’s area from the overall depletion capacitance, which is influenced by the device’s geometry, we applied a methodology involving multiple C-V measurements across diodes with differing diameters and validated the experimental outcomes through rigorous calculations. This enables the utilization of standard capacitance equations. Neglecting the impact of device geometry has the potential to introduce significant inaccuracies in critical device parameters. The proposed methodology addresses these limitations, offering valuable insights to enhance the accuracy of extracted quantities from C-V measurements. Furthermore, it provides guidance for interpreting experimental data obtained from devices incorporating mesa structures.

In this paper, we investigate various graphene monolayer nanomesh structures (diodes) formed only by nanoholes, with a diameter of just 20 nm and etched from the graphene layer in different shapes (such as rhombus, bow tie, rectangle, trapezoid, and triangle), and their electrical properties targeting electromagnetic energy harvesting applications. In this respect, the main parameters characterizing any nonlinear device for energy harvesting are extracted from tens of measurements performed on a single chip containing the fabricated diodes. The best nano-perforated graphene structure is the triangle nanomesh structure, which exhibits remarkable performance in terms of its characteristic parameters, e.g., a 420 Ω differential resistance for optimal impedance matching to an antenna, a high responsivity greater than 103 V/W, and a low noise equivalent power of 847 pW/√Hz at 0 V.

Objective: This article presents technical guidelines for perio‐restorative esthetic crown lengthening, along with a discussion of the biologic rationale. A classification system is proposed to assist in treatment planning and sequencing the surgical and restorative phases. Clinical Considerations: When esthetic crown lengthening is performed as an adjunct to restorative therapy, the surgical approach must be determined by the anticipated position of the restorative margins. The removal of sufficient bone to achieve the desired clinical crown length and preserve the supracrestal gingival tissue dimensions is facilitated by the use of a surgical guide fabricated according to the design of the restorations. A staged approach allows sequencing the provisional restoration to minimize unesthetic sequelae during the healing period. Inadequate bone resection and/or alteration of the soft tissue dimensions results in delayed healing, leading to coronal gingival rebound and biologic width impingement. Conclusion: The identification and preservation of appropriate restorative and biologic landmarks is essential for success in pre‐prosthetic esthetic crown lengthening treatment. A staged approach improves the esthetic management during the postsurgical healing and maturation period. Clinical Significance: A restorative driven classification system for sequencing and staging adjunctive esthetic crown lengthening procedures is presented. Technical guidelines to enhance gingival margin predictability are suggested, accompanied by relevant evidence. In addition, wound healing timelines following gingival and osseous resection are provided. [ABSTRACT FROM AUTHOR]

Copyright of Revista Española de Cirugía Oral y Maxilofacial is the property of Sociedad Espanola de Cirugia Oral y Maxilofacial (SECOM) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The study of the parameters of the recombination centers created by various additives attracts the attention of research scientists. Transition elements such as nickel, tungsten, titanium, etc. are used in their manufacturing technology to improve the parameters of silicon devices and increase the percentage of availability. When the p-n junction is obtained, as a result of high-temperature operation, thermoacceptors are formed in the volume of silicon, and additives that create deep levels within it diffuse, as a result of which the lifetime is significantly reduced. Lifetime varies between 10-9÷10-5 seconds in p-n junction devices. The lifetime of nonmain carriers in thermally treated silicon can be increased by nickel. Therefore, nickel is widely used in the preparation of silicon p-n junctions. However, the mechanism of action of nickel has not been fully clarified and its recombination properties have been partially studied at temperatures above the operating limit of silicon devices (T=4900 K) in nickel-doped samples, recombination again occurs in the centers located in the middle of the band gap (ΔEt=0.54ev). [ABSTRACT FROM AUTHOR]

Energy harvesters provide excellent solutions for the power supply problem of wireless sensor nodes (WSNs), and energy harvesters with a wider bandwidth will clearly better serve WSNs and assist in the construction of Industry 4.0. However, the bearing of rectifiers on the load bandwidth of energy harvesters has rarely been investigated. This paper focuses on the impact of diverse rectifiers on the load electrical response of an electromagnetic energy harvester in the sweep mode of experiments, especially on the load bandwidth. The rectifiers were set as a half-wave rectifier and a full-bridge rectifier, respectively, and two different rectifier diodes were adopted in the experiment. The experimental results suggest that the half-wave rectifier exhibited certain advantages especially in the bandwidth field. If a full-bridge rectifier using high-speed switching diodes is replaced with a half-wave rectifier using Schottky diodes under the load resistance of 100 Ω, the load bandwidth will increase by almost 1.9 times. A preliminary analysis of the experimental results is provided at length. [ABSTRACT FROM AUTHOR]

In this study, a reconfigurable double-sided meander line dipole antenna (RMLA) incorporated with a tapered balun was developed to function at 0.9 GHz, 2.4 GHz, and 3.7 GHz. Furthermore, the suggests antenna functions at three modes at different frequency bands with pattern reconfiguration. Two positive-intrinsic-negative (PIN) diodes were embedded in the two rectangular defected ground structures to accomplish frequency and pattern reconfigurability. With excellent impedance matching, the return loss in each of these bands keeps beneath -10 dB. The suggested antenna was designed using computer simulation technology 2020 and constructed on a FR-4 substrate with a thickness of 1.6 mm, and dielectric constant of 4.3 mm respectively. Additionally, for antenna size reduction, meander line technique was embedded. The fundamental working mechanism of this reconfigurable antenna is accomplished by changing the status of a radio frequency (RF) switches, which is carried out in on or off mode. For the three resonant bands, the suggested antenna has a voltage standing waves ratio (VSWR) < 2. Up to 80%, the suggested structure radiation efficiency and gain (1-2.8) dBi are calculated. The suggested antenna is well suitable for global system mobile, wireless fidelity (WiFi) and C-band applications because of its notable features of high efficiency, good gain and frequency reconfigurability. [ABSTRACT FROM AUTHOR]

In modern electronics, the ionic charges have not occupied the same role as the electrons mainly because of their relatively low mobilities. However, these "slow" charge carriers contribute to brain computing with high efficiency and extremely low power consumption. Inspired by the "ionic" life, iontronic components have recently attracted considerable attention. In this review, we first introduce the progress of iontronic devices operating with the involvement of water, specifically, two types of systems—nanofluidic and hydrogels. Next, the issues and challenges within these liquid-state ionic devices are summarized. To avoid the negative impact of water, we also propose two solid-state materials—ionogels and charged metal nanoparticles—to construct several basic ionic devices such as diodes and transistors. Finally, we summarize this review and outlook the promising directions for the further developments of iontronic devices. [ABSTRACT FROM AUTHOR]

LED (light-emitting diode) drivers with the non-resonant DC-DC converters produce higher current and voltage ripple than the resonant converters. The resonant converter-based LED drivers provide low cost, high efficiency, enhanced soft switching capabilities, and simple construction. Therefore, this research work is motivated to propose a hybrid resonant converter to power the LED. The proposed modified hybrid resonant with valley-fill converter is built by removing the capacitors across the switches and the output diode is replaced with a valley-fill circuit in the conventional hybrid resonant converter. With the valley-fill circuit, the switches and the diode are subjected to reduced stress, reduced flicker, and improved efficiency. The modified Hybrid resonant converter with valley-fill circuit LED driver’s performance parameters are compared with existing resonant converter topologies in terms of component count, current stress, voltage stress across the switch and output diode, LED voltage ripple, current ripple, and efficiency. A 10 W, 24 V laboratory prototype of modified Hybrid resonant converter with valley-fill circuit LED driver is developed, and the simulation results are validated.

We present here the fabrication at the wafer level and the electrical performance of two types of graphene diodes: ballistic trapezoidal-shaped graphene diodes and lateral tunneling graphene diodes. In the case of the ballistic trapezoidal-shaped graphene diode, we observe a large DC current of 200 µA at a DC bias voltage of ±2 V and a large voltage responsivity of 2000 v/w, while in the case of the lateral tunneling graphene diodes, we obtain a DC current of 1.5 mA at a DC bias voltage of ±2 V, with a voltage responsivity of 3000 v/w. An extended analysis of the defects produced during the fabrication process and their influences on the graphene diode performance is also presented.

In hydraulic and pneumatic systems, due to the many factors of their operation, pressure and flow fluctuations inevitably occur. Such fluctuations are formed during the operation of gas-liquid aggregates, during the passage of resistance flow, and their appearance is influenced by the material of manufacture (its rigidity) of the system. As a rule, such phenomena in systems are undesirable and lead to changes in the performance characteristics of the system relative to the calculated data. Thus, there are various mechanisms to "smooth out" the fluctuations of the systems. In hydraulic systems, in particular in lifting machines, I often use special devices for this — dampers. In this paper, it is proposed to use a hydrodiode as a damper. Having a different flow rate in the forward and reverse direction, it provides a different flow-drop characteristic when lifting and lowering the boom. This effect allows you to improve the positioning of the crane boom when lifting and lowering the boom.

Objective: This research compares the clinical outcomes of gingival depigmentation procedures with conventional scalpel, ceramic trimmer bur, and diode laser techniques. Materials and methods: Twenty-four individuals with physiologic gingival hyperpigmentation received random allocation to one of three treatment groups: scalpel, ceramic bur, or diode laser. Pain score, operation time, bleeding index, degree of epithelialization, wound healing, Dummett-Gupta Oral Pigmentation Index (DOPI), and Takashi Index score changes were all investigated at different time points. Results: At 12-h follow-up, significant variations in pain scores were seen between the laser and scalpel groups (p = 0.003) but not between the laser and ceramic bur groups. The diode laser group completed the procedure significantly quicker than the scalpel and ceramic bur groups (p = 0.004 and p = 0.001, respectively). The ceramic trimmer bur and diode laser groups showed significantly less bleeding tendency than the scalpel group. Wound healing and the degree of epithelialization were similar in all groups. DOPI and Takashi indices significantly decreased compared to baseline in all groups, with no significant difference recorded between all groups. Conclusion: While diode lasers are a safe and effective treatment option for gingival hyperpigmentation, providing optimal aesthetics with reduced discomfort to patients, a ceramic trimmer bur can also be used as a simple and affordable alternative to a laser in gingival depigmentation procedures. Clinical relevance: Gingival hyperpigmentation is a major aesthetic issue for many individuals. Laser and ceramic trimmer bur treatments produce equivalent aesthetic outcomes for gingival hyperpigmentation. [ABSTRACT FROM AUTHOR]

Low-level laser therapy (LLLT) is known for its ability to induce a photochemical process, primarily targeting mitochondria, a process referred to as photobiomodulation (PBM). Recently, its use has been attributed as an adjunct in obesity treatment, to stimulate lipolysis and apoptosis. However, the pathway of stimulation remains uncertain. Thus, the objective of this study was to understand whether mitochondrial stimulation occurs in adipose tissue cells after PBM therapy, which could lead to the processes of lipolysis and apoptosis. A non-randomized clinical trial was conducted using a split abdomen design in obese women who received red and infrared LED photobiomodulation therapy (PBMT). The patients underwent bariatric surgery, and adipose tissue samples were collected for immunohistochemical analysis with primary mitochondrial antibodies. Adipose tissue samples subjected to LED intervention exhibited positivity in mitochondrial antibodies for cAMP, DRP1, FAS, FIS1, MFN2, and OPA1 (p<0.001) compared to the control group. In conclusion, we observed that PBMT was capable of generating mitochondrial stimulation in adipose tissue cells, as evidenced by the positive antibody signals. This finding suggests that mitochondrial stimulation could be the mechanism and action underlying adipose tissue lipolysis and apoptosis. [ABSTRACT FROM AUTHOR]

Background and Purpose: Rose is one of the most well-known ornamental cut flowers all over the world and high quality cut roses production in greenhouses is very important. Rose flower is a light-loving plant among ornamental flowers, and providing adequate light during the cultivation period is one of the important measures in increasing the yield and quality of greenhouse roses, in low light and cloudy days. Increasing the light available to roses in greenhouse cultivation is done by using supplementary light sources. During the last few years, the use of new supplementary lights as an alternative to old light sources in improving the growth and development conditions of ornamental plants has received much attention. For this purpose, the present study was conducted with the aim of investigating the effect of supplementary light source on the morphological and physiological indicators of ‘Jumilia’ rose. New supplementary lights, including combined light emitting diode (LED), were compared to conventional and old light sources such as metal halide (MH) and high-pressure sodium (HPS) to determine the optimal supplementary light source for the production of ‘Jumilia’ cut roses by hydroponic method, and natural sunlight during the cold season was used as control. Materials and Methods: This experiment was conducted in the form of a completely randomized design with four light treatment groups including metal vapor supplementary lights, sodium high pressure, combined light emitting diodes and control (natural sunlight without supplementary exposure) in three replications and each replication includes four plants. The experiment was carried out in the specialized rose greenhouse located in the research greenhouse of the Faculty of Agriculture of Isfahan University of Technology in 1399-1400. In this research, morphological and physiological traits including bud length, flower stem diameter, calyx diameter, number of leaves at the time of flowering, number of flowers, amount of leaf chlorophylls a and b, relative leaf water content, leaf protein and leaf chlorophyll fluorescence of ‘Jumilia’ rose was measured. Results: Based on the obtained results, the effect of supplementary light treatments on the morphogenesis, morphological and physiological traits of ‘Jumilia’ cut roses were significant. Compared to the control treatment, the treatment of combined light diodes had the greatest effect on the indicators of bud length, diameter of flower stalk and diameter of calyx; A similar result was obtained in increasing the number of leaves and the number of flower branches. Also, the accumulation of leaf photosynthetic pigments, including chlorophylls, showed the greatest increase in light treatment with combined diodes. Growth light diodes were able to increase the relative water content of leaves significantly compared to other treatments. The amount of protein measured in rose leaf tissue treated with combined light diodes was higher than other treatments. By examining the chlorophyll fluorescence index, it was found that light diodes provided more suitable growing conditions for the growth of rose bushes. Among the investigated treatments, the highest quantity and quality of ‘Jumilia’ cut roses were created by combined light emitting diode treatments compared to other supplementary light treatments as well as the control treatment. Conclusion: Considering the favorable effects of combined light diode treatments on the quantitative and qualitative characteristics of ‘Jumilia’ rose and considering the higher energy efficiency and economic efficiency in a longer period of time in greenhouse cultivation, the use of combined light diodes in lighting supplementation of intensive crops is a priority. Combined diode supplementary lights are recommended due to their significant superiority over the control and their positive role in improving the growth and development of ‘Jumilia’ roses; Also, the complementary light of combined diodes is recommended as an alternative to metal vapor and high pressure sodium. [ABSTRACT FROM AUTHOR]

The synthesis of the nanosized multifunctional thin film provides new solutions for many technological issues and consider a great step for miniaturized technology. Toward these goals, AgSbTe 2 semi-nanocrystalline thin films of different thicknesses were synthesized by the thermal evaporation technique. The structural features were investigated by X-ray diffraction, and selected area electron diffraction (SAED) yielding a semi-nanocrystalline thin film of grain size ranging from 9.98 to 21.38 nm. The energy-dispersive X-ray spectroscopy (EDAX) verified the high purity and stoichiometry of the deposited films. For optoelectronic application, many optical parameters, including band gap (E g), Urbach energy (E u), Refractive index (n), dispersion energy (E d), electronic polarizability (α e), and interband transition strength (J CV) were extensively discussed. The optical band gap reduced from 1.41 to 1.04 eV upon increasing the thickness from 150 to 550 nm. The temperature dependence of the electrical resistivity (ρ) of nanosized thin film was measured and the activation energy was estimated and it was found that the resistivity increased up to 450 K asserting the semiconductor behavior of the films. As for diode application, The Ag/2D-MoS 2 /p-AgSbTe 2 (550 nm)/n-Si/Al heterostructure diode was constructed by thermal evaporation and all the diode parameters alongside conduction mechanism were studied in detail. AgSbTe 2 -based diode showed a low rectification ratio; however, the ideality factor (n) and zero bias barrier height (Φ b) had optimal values of about 1.40 and 0.75 at room temperature, respectively. [ABSTRACT FROM AUTHOR]

Due to the variety of benefits over traditional cutting techniques, the usage of laser cutting technology has risen substantially in recent years. The attributes of laser technology for leather cutting include adaptability, mass production, capability of cutting complicated patterns, ease of producing tailored components, and reduction in leather waste. In the present study, vegetable chrome-tanned buffalo leather specimens were cut using a 20 W laser diode with conventional and pulse width control in a photodiode-assisted laser cutting process. Emission rate, kerf width, carbonization, and material removal rate were considered as quality indicators. The higher power density associated with the pulse width approach reduces the interaction with the specimen, which results in a better emission rate and material removal rate, along with a lesser kerf width and carbonization. Using the MOORA approach, the optimal parameters of the present study were found to be a stand-off distance of 22 mm, a feed rate of 200 mm/min, a duty cycle of 75%, and a frequency of 20 kHz. The duty cycle can effectively control the pulse width at which the energy has been dissipated across the cutting zone. [ABSTRACT FROM AUTHOR]

This study aims to exploit the distinctive properties of carbon nanotube materials, which are particularly pronounced at the microscopic scale, by deploying fabrication techniques that allow their features to be observed macroscopically. Specifically, we aim to create a semiconductor device that exhibits flexibility and the ability to modulate its electromagnetic wave absorption frequency by means of biasing. Initially, we fabricate a sheet of carbon nanotubes through a vacuum filtration process. Subsequently, phosphorus and boron elements are separately doped into the nanotube sheet, enabling it to embody the characteristics of a PN diode. Measurements indicate that, in addition to the fundamental diode's current–voltage relationship, the device also demonstrates intriguing transmission properties under the TEM mode of electromagnetic waves. It exhibits a frequency shift of approximately 2.3125 GHz for each volt of bias change. The final result is a lightweight and flexible carbon-based semiconductor microwave filter, which can conform to curved surfaces. This feat underscores the potential of such materials for innovative and effective electromagnetic wave manipulation. [ABSTRACT FROM AUTHOR]

Implantable central venous (CV) ports are widely used for chemotherapy and parenteral nutrition. Generally, CV ports are used safely; however, some patients suffer from drug leakage around the port septum due to mispuncture. Therefore, we developed a CV port that is visible under the skin. We created a prototype of a CV port using a 3D printer. Three red light-emitting diodes (LEDs) were attached around the septum that made the puncture site visible by applying wireless energy transmission technology using electromagnetic resonance. The CV port was implanted under the skin of pork rose meat. The thickness of the skin of pork loin was measured. Fifteen medical doctors participated in the study to visually confirm the lighted CV port. The visibility of the center of the septum with and without lights was scored 0 as non-diagnostic; 1, slightly visible; 2, well visible; and 3, obviously visible. The visibility with or without lights was assessed. The relationship between the years of experience and the visibility score was assessed. The Wilcoxon test was used for statistical analysis. LEDs were easily transmitted through the skin of pork rose meat. The median visibility scores with or without lights were 2 (range, 1–3) and 3 (range, 1–3), respectively (p = 0.005). No significant relationship was found between experience and visibility score (p = 0.289). CV ports with LEDs can be easily recognized compared with those without LEDs. This technique may contribute to medical safety by improving its visibility to avoid mispuncture. [ABSTRACT FROM AUTHOR]

We have designed a passive spintronic diode based on a single skyrmion stabilized in a magnetic tunnel junction and studied its dynamics induced by voltage-controlled magnetic anisotropy (VCMA) and Dzyaloshinskii–Moriya interaction (VDMI). We have demonstrated that the sensitivity (rectified output voltage over input microwave power) with realistic physical parameters and geometry can be larger than 10 kV W−1 which is one order of magnitude larger than diodes employing a uniform ferromagnetic state. Our numerical and analytical results on the VCMA and VDMI-driven resonant excitation of skyrmions beyond the linear regime reveal a frequency dependence on the amplitude and no efficient parametric resonance. Skyrmions with a smaller radius produced higher sensitivities, demonstrating the efficient scalability of skyrmion-based spintronic diodes. These results pave the way for designing passive ultra-sensitive and energy efficient skyrmion-based microwave detectors. [ABSTRACT FROM AUTHOR]