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Spectrochimica Acta. Part A, Molecular... Jun 2024This research entails the synthesis and catalytic exploration of bimetallic nanoparticles combining silver (Ag) and gold (Au). The Au concentration was systematically...
This research entails the synthesis and catalytic exploration of bimetallic nanoparticles combining silver (Ag) and gold (Au). The Au concentration was systematically varied (20%, 40%, 60%, and 80%), alongside the utilization of CTAB surfactant for nanoparticle stabilization. UV visible spectroscopic analysis confirmed the formation and stability of synthesized Au, Ag and bimetallic (Ag-Au) nanoparticles. FESEM further confirmed the formation of uniform sized Au and Ag nanoparticles. Integration of Au into Ag resulted in bimetallic (Ag-Au) alloy nanoparticles with smaller dimensions as compared to individual Au and Ag nanoparticles. EDX spectra and mapping verified the composition of each synthesized bimetallic nanoparticle variant. The catalytic potential of the synthesized nanoparticles was methodically explored using UV-visible spectroscopy. All the synthesized nanoparticles showcased excellent catalytic efficacy. The synergistic effect of the alloyed bimetallic nanoparticles was found promising. Assessment of dye toxicity pre- and post-degradation was conducted using the ECOSAR program, indicating a reduction in dye toxicity following degradation.
PubMed: 38936211
DOI: 10.1016/j.saa.2024.124705 -
Journal of the American Chemical Society Jun 2024Electrocatalytic semihydrogenation of alkynols presents a sustainable alternative to conventional thermal methodologies for the high-value production of alkenols. The...
Electrocatalytic semihydrogenation of alkynols presents a sustainable alternative to conventional thermal methodologies for the high-value production of alkenols. The design of efficient catalysts with superior catalytic and energy efficiency for semihydrogenation poses a significant challenge. Here, we present the application of an electron-divergent CuPd alloy-based heterojunction in promoting the electrocatalytic semihydrogenation of alkynols to alkenols using water as the proton source. The tunable electron divergence of Cu and Pd, modulated by rectifying contact with nitrogen-rich carbons, enables the concerted binding of active H species from the Volmer step of water dissociation and the C≡C bond of alkynols on Pd sites. Simultaneously, the pronounced electron divergence of CuPd facilitates the universal adsorption of OH species from the Volmer step and alkynols on the Cu sites. The electron-divergent dual-center substantially boosts water dissociation and inhibition of completing hydrogen evolution to give a turnover frequency of 2412 h, outperforming the reported electrocatalysts' value of 7.3. Moreover, the continuous production of alkenols at industrial-related current density (-200 mA cm) over the efficient and durable CuPd-based electrolyzer could achieve a cathodic energy efficiency of 45 mol kW·h, 1.7 times the bench-marked reactors, promising great potential for sustainable industrial synthesis.
PubMed: 38935866
DOI: 10.1021/jacs.4c03893 -
Journal of the American Chemical Society Jun 2024High-entropy alloy nanoparticles (HEA-NPs) show exceptional properties and great potential as a new generation of functional materials, yet a universal and facile...
High-entropy alloy nanoparticles (HEA-NPs) show exceptional properties and great potential as a new generation of functional materials, yet a universal and facile synthetic strategy in air toward nonoxidized and precisely controlled composition remains a huge challenge. Here we provide a laser scribing method to prepare single-phase solid solution HEA-NPs libraries in air with tunable composition at the atomic level, taking advantage of the laser-induced metastable thermodynamics and substrate-assisted confinement effect. The three-dimensional porous graphene substrate functions as a microreactor during the fast heating/cooling process, which is conductive to the generation of the pure alloy phase by effectively blocking the binding of oxygen and metals, but is also beneficial for realizing accurate composition control via microstructure confinement-endowed favorable vapor pressure. Furthermore, by combining an active learning approach based on an adaptive design strategy, we discover an optimal composition of quinary HEA-NP catalysts with an ultralow overpotential for Li-CO batteries. This method provides a simple, fast, and universal in-air route toward the controllable synthesis of HEA-NPs, potentially integrated with machine learning to accelerate the research on HEAs.
PubMed: 38935530
DOI: 10.1021/jacs.4c03658 -
Indian Journal of Dental Research :... Jan 2024The application of direct current can have a significant impact on the rate of tooth movement and surrounding periodontal ligament collagen turnover. This study aims to... (Comparative Study)
Comparative Study
An Immunohistochemical and Histological Study of the Animal Periodontal Ligament During Orthodontic Force Application with Concomitant Application of Electric Current - An Animal Study.
INTRODUCTION
The application of direct current can have a significant impact on the rate of tooth movement and surrounding periodontal ligament collagen turnover. This study aims to provide insight into the optimal characteristics of applied current to achieve enhanced tissue response.
METHOD
Eighteen male Wistar rats were divided into three groups (I, II, and III). Split mouth design was used, and each side was allocated into an experimental group or control group. Experimental sides of groups I, II, and III received 20, 10, and 15 μA of current (15 min, twice daily for 3 days). Both the experimental and control groups receive an orthodontic force via the NiTi closed coil spring. The amount of tooth movement was determined daily. Immunohistochemistry slides were scored using the immunoreactive scoring (IRS) system for collagen types I and III. One-way Analysis of Variance (ANOVA) and Tukey post hoc test were used to analyse the rate of tooth movement, while Mann-Whitney test was used to analyse IRS distribution between control and experimental groups.
RESULTS
Compared with the control group, there was a statistically significant difference in tooth movement in all the experimental groups, with group 3 showing the maximum rate on days 2 and 3. This was supported by immunoreactive scores for both collagen types I and III.
CONCLUSIONS
After 72 hours, the expression of collagen types 1 and 3 increased significantly for group III. This finding was in harmony with the rate of tooth movement, which was maximum for group 3 (15 μA) as compared to other groups.
Topics: Periodontal Ligament; Animals; Rats, Wistar; Tooth Movement Techniques; Male; Rats; Collagen Type I; Immunohistochemistry; Collagen Type III; Orthodontic Wires; Dental Alloys; Nickel; Stress, Mechanical; Titanium
PubMed: 38934753
DOI: 10.4103/ijdr.ijdr_905_22 -
Small (Weinheim An Der Bergstrasse,... Jun 2024Industrial urea synthesis production uses NH from the Haber-Bosch method, followed by the reaction of NH with CO, which is an energy-consuming technique. More thorough... (Review)
Review
Industrial urea synthesis production uses NH from the Haber-Bosch method, followed by the reaction of NH with CO, which is an energy-consuming technique. More thorough evaluations of the electrocatalytic C-N coupling reaction are needed for the urea synthesis development process, catalyst design, and the underlying reaction mechanisms. However, challenges of adsorption and activation of reactant and suppression of side reactions still hinder its development, making the systematic review necessary. This review meticulously outlines the progress in electrochemical urea synthesis by utilizing different nitrogen (NO , N, NO , and NO) and carbon (CO and CO) sources. Additionally, it delves into advanced methods in materials design, such as doping, facet engineering, alloying, and vacancy introduction. Furthermore, the existing classes of urea synthesis catalysts are clearly defined, which include 2D nanomaterials, materials with Mott-Schottky structure, materials with artificially frustrated Lewis pairs, single-atom catalysts (SACs), and heteronuclear dual-atom catalysts (HDACs). A comprehensive analysis of the benefits, drawbacks, and latest developments in modern urea detection techniques is discussed. It is aspired that this review will serve as a valuable reference for subsequent designs of highly efficient electrocatalysts and the development of strategies to enhance the performance of electrochemical urea synthesis.
PubMed: 38934550
DOI: 10.1002/smll.202403412 -
Archivio Italiano Di Urologia,... Jun 2024The retention of foreign bodies inside the body during ludic/sexual procedures or for traumatism represents one of the causes of visits to accident and emergency...
BACKGROUND
The retention of foreign bodies inside the body during ludic/sexual procedures or for traumatism represents one of the causes of visits to accident and emergency departments that often requires surgical removal of the foreign body. However, there are cases where the discovery of such foreign bodies takes place after many years, as in patients that are slightly compromised from a neuro-sociological point of view.
CASE PRESENTATION
A 76-year-old male presented to an outpatient urological examination due to an increase in scrotal volume. At the ultrasound check, an acoustic interference from a solid object was detected, for which computed tomography was requested. The computed tomography scan revealed the presence of an elongated metal body in the perineum. The removal of the foreign body in the operating theatre was then scheduled. A 10 cm long stainless-steel nail located within an abscessed foreign body granuloma was identified and removed via a scrotal access. Four days later, a new surgical toilet was performed due to minimal necrosis of the skin flaps. The patient then performed three more dressings in the operating theatre during the following week. Healing took place by secondary intention until a perfect healing of the surgical wound was obtained.
CONCLUSIONS
Removal of foreign bodies from the perineum in case of infection can be challenging. Careful attention and postoperative dressings are crucial for the success of the case.
Topics: Humans; Male; Aged; Foreign Bodies; Scrotum; Stainless Steel; Nails; Tomography, X-Ray Computed
PubMed: 38934526
DOI: 10.4081/aiua.2024.12363 -
ACS Applied Materials & Interfaces Jun 2024Femtosecond laser ablation of CuZn targets in ethanol led to the formation of periodic surface nanostructures and crystalline CuZn alloy nanoparticles with defects,...
Femtosecond laser ablation of CuZn targets in ethanol led to the formation of periodic surface nanostructures and crystalline CuZn alloy nanoparticles with defects, low-coordinated surface sites, and, controlled by the applied laser fluence, different sizes and elemental composition. The Cu/Zn ratio of the nanoparticles was determined by energy dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, and selected area electron diffraction. The CuZn nanoparticles were about 2-3 nm in size, and Cu-rich, varying between 70 and 95%. Increasing the laser fluence from 1.6 to 3.2 J cm yielded larger particles, more stacking fault defects, and repeated nanotwinning, as evident from high-resolution transmission electron microscopy, aided by (inverse) fast Fourier transform analysis. This is due to the higher plasma temperature, leading to increased random collisions/diffusion of primary nanoparticles and their incomplete ordering due to immediate solidification typical of ultrashort pulses. The femtosecond laser-synthesized often nanotwinned CuZn nanoparticles were supported on highly oriented pyrolytic graphite and applied for ethylene hydrogenation, demonstrating their promising potential as model catalysts. Nanoparticles produced at 3.2 J cm exhibited lower catalytic activity than those made at 2.7 J cm. Presumably, agglomeration/aggregation of especially 2-3 nm sized nanoparticles, as observed by postreaction analysis, resulted in a decrease in the surface area to volume ratio and thus in the number of low-coordinated active sites.
PubMed: 38934369
DOI: 10.1021/acsami.4c07766 -
Small (Weinheim An Der Bergstrasse,... Jun 2024Tin-halide perovskites (THP) are emerging materials for photovoltaics with optoelectronic properties potentially rivaling lead-based analoges. Their efficiencies in...
Tin-halide perovskites (THP) are emerging materials for photovoltaics with optoelectronic properties potentially rivaling lead-based analoges. Their efficiencies in solar cells are, however, severely limited by the high sensitivity of tin to oxygen and the heavy p-doping natively present in the material. While the effects of oxygen can be mitigated by using reducing agents upon the synthesis and by encapsulating the device, the native p-doping caused by the high density of acceptor defects remains a challenge to be further addressed for prolonging carrier lifetimes and, consequently, device efficiency. In this work, potential compositional engineering strategies aimed at reducing the p-doping of this class of materials and increasing their efficiency in solar cells are investigated. Based on density functional theory simulations it is demonstrated that THP doping with ds trivalent ions effectively decreases the hole background density and the density of the deep defects responsible for the non-radiative recombination in these materials. This effect is enhanced by alloying iodide with small fractions of bromide, up to 33%. Higher bromide fractions, instead, are detrimental due to the increased non-radiative recombination. These results may provide useful guidelines to experimentalists for improving the optoelectronic quality of THPs and consequently of the ensuing devices.
PubMed: 38934357
DOI: 10.1002/smll.202403413 -
Small (Weinheim An Der Bergstrasse,... Jun 2024Electrocatalysis is a crucial method for achieving global carbon neutrality, serving as an essential means of energy conversion, and electrocatalyst is crucial in the... (Review)
Review
Electrocatalysis is a crucial method for achieving global carbon neutrality, serving as an essential means of energy conversion, and electrocatalyst is crucial in the process of electrocatalysis. Because of the abundant active sites, the multi-component synergistic effect of high-entropy materials has a wide application prospect in the field of electrocatalysis. Moreover, due to the special structure of high-entropy materials, it is possible to obtain almost continuous adsorption energy distribution by regulating the composition, which has attracted extensive attention of researchers. This paper reviews the properties and types of high-entropy materials, including alloys and compounds. The synthesis strategies of high-entropy materials are systematically introduced, and the solid phase synthesis, liquid-phase synthesis, and gas-phase synthesis are classified and summarized. The application of high-entropy materials in electrocatalysis is summarized, and the promotion effect of high-entropy strategy in various catalytic reaction processes is summarized. Finally, the current progress of high-entropy materials, the problems encountered, and the future development direction are reviewed. It is emphasized that the strategy of high flux density functional theory calculation guiding high-entropy catalyst design will be of great significance to electrocatalysis.
PubMed: 38934346
DOI: 10.1002/smll.202403162 -
Small Methods Jun 2024The evolutions of chip thermal management and micro energy harvesting put forward urgent need for micro thermoelectric devices. Nevertheless, low-performance...
The evolutions of chip thermal management and micro energy harvesting put forward urgent need for micro thermoelectric devices. Nevertheless, low-performance thermoelectric thick films as well as the complicated precision cutting process for hundred-micron thermoelectric legs still remain the bottleneck hindering the advancement of micro thermoelectric devices. In this work, an innovative direct melt-calendaring manufacturing technology is first proposed with specially designed and assembled equipment, that enables direct, rapid, and cost-effective continuous manufacturing of BiTe-based films with thickness of hundred microns. Based on the strain engineering with external glass coating confinement and controlled calendaring deformation degree, enhanced thermoelectric performance has been achieved for (Bi,Sb)Te thick films with highly textured nanocrystals, which can promote carrier mobility over 182.6 cm V s and bring out a record-high zT value of 0.96 and 1.16 for n-type and p-type (Bi,Sb)Te thick films, respectively. The nanoscale interfaces also further improve the mechanical strength with excellent elastic modules (over 42.0 GPa) and hardness (over 1.7 GPa), even superior to the commercial zone-melting ingots and comparable to the hot-extrusion (Bi,Sb)Te alloys. This new fabrication strategy is versatile to a wide range of inorganic thermoelectric thick films, which lays a solid foundation for the development of micro thermoelectric devices.
PubMed: 38934342
DOI: 10.1002/smtd.202400589