A Method for Precise Reduction of Facial Bone Fractures Using Intraoperative Ultrasound With a Solid Gel Pad as a Coupling Medium.

This study introduces a method to overcome technical challenges in using intraoperative ultrasound for the closed reduction of nasal bone and zygomatic arch fractures. The curvature of the face makes it difficult to apply an ultrasound probe to the facial area. We used a solid gel pad as a coupling medium during surgery to improve the scanning of facial bone fractures. The results show that the fracture sites observed on preoperative computed tomography scans can be easily visualized using intraoperative ultrasound, and real-time manipulation confirms successful reduction. The solid gel pad is light, malleable, easy to use, and provides accurate images. Overall, the use of ultrasound with a solid gel pad enhances the accuracy of closed reduction in facial bone fracture surgeries, confirming fracture patterns and ensuring precise reduction.

Surface-Modified Carbon Nanotubes with Ultrathin Co3O4 Layer for Enhanced Oxygen Evolution Reaction.

Alkaline water electrolysis is a vital technology for sustainable and efficient hydrogen production. However, the oxygen evolution reaction (OER) at the anode suffers from sluggish kinetics, requiring overpotential. Precious metal-based electrocatalysts are commonly used but face limitations in cost and availability. Carbon nanostructures, such as carbon nanotubes (CNTs), offer promising alternatives due to their abundant active sites and efficient charge-transfer properties. Surface modification of CNTs through techniques such as pulsed laser ablation in liquid media (PLAL) can enhance their catalytic performance. In this study, we investigate the role of surface-modified carbon (SMC) as a support to increase the active sites of transition metal-based electrocatalysts and its impact on electrocatalytic performance for the OER. We focus on Co3O4@SMC heterostructures, where an ultrathin layer of Co3O4 is deposited onto SMCs using a combination of PLAL and atomic layer deposition. A comparative analysis with aggregated Co3O4 and Co3O4@pristine CNTs reveals the superior OER performance of Co3O4@SMC. The optimized Co3O4@SMC exhibits a 25.6% reduction in overpotential, a lower Tafel slope, and a significantly higher turnover frequency (TOF) in alkaline water splitting. The experimental results, combined with density functional theory (DFT) calculations, indicate that these improvements can be attributed to the high electrocatalytic activity of Co3O4 as active sites achieved through the homogeneous distribution on SMCs. The experimental methodology, morphology, composition, and their correlation with activity and stability of Co3O4@SMC for the OER in alkaline media are discussed in detail. This study contributes to the understanding of SMC-based heterostructures and their potential for enhancing electrocatalytic performance in alkaline water electrolysis.

Removal of an intraosseous hemangioma of the frontal bone through an anterior hairline incision: a case report.

An intraosseous hemangioma of the frontal bone is typically removed via a coronal incision. This procedure, while effective, can be lengthy and may result in complications such as a prominent scar and hair loss. An alternative approach involves a direct incision in the forehead, which leaves a less noticeable scar and allows a quicker recovery. However, in this specific case, the patient declined both coronal surgery and surgery through a direct forehead incision due to cosmetic concerns. Therefore, we proposed an anterior hairline incision. A 35-year-old woman presented with a firm, non-mobile, palpable mass on her right forehead. Preoperative non-contrast computed tomography revealed a heterogeneous osteolytic lesion. We performed an excisional biopsy through the anterior hairline. Postoperative non-contrast computed tomography was conducted 2 and 6 months after surgery. The wound was clean and free of complications, and there was no local recurrence. Partial resection can reduce scarring for patients who are concerned about cosmetic outcomes. However, the potential for recurrence remains a significant concern. We present this case of an anterior hairline incision for a hemangioma located in the forehead, evaluated using serial computed tomography for both preoperative and postoperative imaging.

Colossal Dielectric Perovskites of Calcium Copper Titanate (CaCu3 Ti4 O12 ) with Low-Iridium Dopants Enables Ultrahigh Mass Activity for the Acidic Oxygen Evolution Reaction.

Oxygen evolution reaction (OER) under acidic conditions becomes of significant importance for the practical use of a proton exchange membrane (PEM) water electrolyzer. In particular, maximizing the mass activity of iridium (Ir) is one of the maiden issues. Herein, the authors discover that the Ir-doped calcium copper titanate (CaCu3Ti4O12, CCTO) perovskite exhibits ultrahigh mass activity up to 1000 A gIr -1 for the acidic OER, which is 66 times higher than that of the benchmark catalyst, IrO2 . By substituting Ti with Ir in CCTO, metal-oxygen (M-O) covalency can be significantly increased leading to the reduced energy barrier for charge transfer. Further, highly polarizable CCTO perovskite referred to as "colossal dielectric", possesses low defect formation energy for oxygen vacancy inducing a high number of oxygen vacancies in Ir-doped CCTO (Ir-CCTO). Electron transfer occurs from the oxygen vacancies and Ti to the substituted Ir consequentially resulting in the electron-rich Ir and -deficient Ti sites. Thus, favorable adsorptions of oxygen intermediates can take place at Ti sites while the Ir ensures efficient charge supplies during OER, taking a top position of the volcano plot. Simultaneously, the introduced Ir dopants form nanoclusters at the surface of Ir-CCTO, which can boost catalytic activity for the acidic OER.

Pulsed Laser Confinement of Single Atomic Catalysts on Carbon Nanotube Matrix for Enhanced Oxygen Evolution Reaction.

The design of atomically dispersed single atom catalysts (SACs) must consider high metal-atom loading amount, effective confinement, and strong interactions with matrix, which can maximize their catalytic performance. Here reported is a promising method to synthesize SACs on highly conductive multiwall carbon nanotube (MWCNT) supports using pulsed laser confinement (PLC) process in liquid. Atomic cobalt (Co) and phosphorus (P) with a high loading density are homogeneously incorporated on the outer wall of the MWCNT (Co-P SAC MWCNT). Density functional theory (DFT) calculations in combination with systematic control experiments found that the incorporated Co and P adatoms act as an adsorption energy optimizer and a charge transfer promoter, respectively. Hence, favorable kinetics and thermodynamics in Co-P SAC MWCNT can be simultaneously achieved for water oxidation resulting in a superior catalytic performance than the benchmark RuO2 catalyst. Crucially, total processing time for assembling Co-P SAC MWCNT via PLC process is less than 60 min, shedding light on the promising practical applications of our SAC design strategy.

One-step synthesis of sulfur-incorporated graphene quantum dots using pulsed laser ablation for enhancing optical properties.

To tune the electronic and optoelectronic properties of graphene quantum dots (GQDs), heteroatom doping (e.g., nitrogen (N), boron (B), and sulfur (S)) is an effective method. However, it is difficult to incorporate S into the carbon framework of GQDs because the atomic size of S is much larger than that of C atoms, compared to N and B. In this study, we report a simple and one-step method for the synthesis of sulfur-doped GQDs (S-GQDs) via the pulsed laser ablation in liquid (PLAL) process. The as-prepared S-GQDs exhibited enhanced fluorescence quantum yields (0.8% → 3.89%) with a huge improved absorption band in ultraviolet (UV) region (200 ∼ 400 nm) and excellent photo stability under the UV radiation at 360 nm. In addition, XPS results revealed that the PLAL process can effectively facilitate the incorporation of S into the carbon framework compared to those produced by the chemical exfoliation method (e.g., hydrothermal method). And also, the mechanisms related with the optical properties of S-GQDs was investigated by time-resolved photoluminescence (TRPL) spectroscopy. We believe that the PLAL process proposed in this study will serve as a simple and one-step route for designing S-GQDs and opens up to opportunities for their potential applications.

Fundamental Understanding of the Formation Mechanism for Graphene Quantum Dots Fabricated by Pulsed Laser Fragmentation in Liquid: Experimental and Theoretical Insight.

The pulsed laser fragmentation in liquid (PLFL) process is a promising technique for the synthesis of carbon-based functional materials. In particular, there has been considerable attention on graphene quantum dots (GQDs) derived from multiwalled carbon nanotubes (MWCNTs) by the PLFL process, owing to the low cost and rapid processing time involved. However, a fundamental deep understanding of the formation of GQDs from MWCNTs by PLFL has still not been achieved despite the high demand. In this work, a mechanism for the formation of GQDs from MWCNTs by the PLFL process is reported, through the combination of experimental and theoretical studies. Both the experimental and computational results demonstrate that the formation of GQDs strongly depends on the pulse laser energy. Both methods demonstrate that the critical energy point, where a plasma plume is generated on the surface of the MWCNTs, should be precisely maintained to produce GQDs; otherwise, an amorphous carbon structure is favorably formed from the scattered carbons.

Publisher Correction: Graphene Oxide Quantum Dots Derived from Coal for Bioimaging: Facile and Green Approach.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Graphene Oxide Quantum Dots Derived from Coal for Bioimaging: Facile and Green Approach.

Graphene oxide quantum dots (GOQDs) are usually prepared using expensive carbon precursors such as carbon nanotubes (CNT) or graphene under the strong acidic condition, which requires an additional purifying process. Here, we first develop a facile pulsed laser ablation in liquid (PLAL) technique for preparing GOQDs using earth-abundant and low-cost coal as a precursor. Only ethanol and coal are used to produce GOQDs with excellent optical properties. The prepared GOQDs exhibit excellent optoelectronic properties which can be successfully utilized in bioimaging applications.

Laser wavelength modulated pulsed laser ablation for selective and efficient production of graphene quantum dots.

Graphene quantum dots (GQDs) and graphene oxide quantum dots (GOQDs) can be used in different applications such as optoelectronic and biomedical applications, respectively. Hence, the selective synthesis of GQDs and GOQDs is highly desirable but challenging. Here, we present GQDs and GOQDs selectively prepared by an easy and simple pulsed laser ablation in liquid (PLAL) method by controlling the laser wavelength. The obtained GQDs and GOQDs showed a significantly different optoelectronic nature mainly due to the existence of surface oxygen-rich functional groups (e.g. carboxyl or hydroxy groups). Also, we described a possible mechanism for the formation of oxygen functional groups during the PLAL process based on the Coulomb explosion model, which can give further insight for designing functional carbon materials.

Fabrication of Ti-0.48Al Alloy by Centrifugal Casting.

Many of the unique properties of TiAl alloys that make are attractive for use in high-temperature structural applications also make it challenging to process them into useful products. Cast TiAl is rapidly nearing commercialization, particularly in the vehicle industry, owing to its low production cost. In this study, the centrifugal casting of a TiAl (Ti-48%Al, mole fraction) turbocharger was simulated and an experimental casting was created in vacuum using an induction melting furnace coupled to a ceramic composite mold. Numerical simulation results agreed with the experiment. The crystal structure, microstructure, and chemical composition of the TiAl prepared by centrifugal casting were studied by X-ray diffractometry, optical microscopy, field emission scanning electron microscopy (FE-SEM) and energy dispersive spectroscopy (EDS). FE-SEM and EDS examinations of the TiAl casting revealed that the thickness of the oxide layer (α-case) was typically less than 35 µm.

The Effect of Precursor Composition on the Structural Properties of Nanocrystalline Diamond Films.

Nanocrystalline diamond (NCD) films were grown by hot filament CVD and the precursor composition dependence of the structural properties was examined. Films grown at 1 and 2 CH4 Vol% were found to be NCD layers with grain sizes of ~23-25 nm while films grown at 3-5 Vol% were identified as the mixtures of microcrystalline diamond and graphitic phase. The sp2/sp3 bonded carbon ratio in the grown films increased as the CH4 content increased up to 3 Vol% and then decreased beyond 4 Vol%. Microstructure and deposition rate were also found to be affected by the precursor composition and the NCD film grown at 1 CH4 Vol% showed a very dense microstructure and the highest deposition rate of ~3 nm/min.

Few-layered metallic 1T-MoS2/TiO2 with exposed (001) facets: two-dimensional nanocomposites for enhanced photocatalytic activities.

Titanium dioxide (TiO2) with exposed (001) facets (TiO2(001)) has attractive photocatalytic properties. However, the high recombination rate of the photo-excited charge carriers on this surface often limits its application. Here, we report that a few-layered 1T-MoS2 coating on TiO2(001) nanosheets (abbreviated as MST) can be a promising candidate that overcomes some of the challenges of TiO2(001). Computational and experimental results demonstrate that MST as a photocatalyst exhibits a significantly low-charge recombination rate as well as excellent long-term durability. The synthesized MST 2D nanocomposites show a 31.9% increase in photocatalytic activity for hydrogen (H2) production relative to the counterpart TiO2(001). MST offers a new route for further improvement of the photocatalytic activity of TiO2 with exposed high energy facets.

Ultrafast Method for Selective Design of Graphene Quantum Dots with Highly Efficient Blue Emission.

Graphene quantum dots (GQDs) have attractive properties and potential applications. However, their various applications are limited by a current synthetic method which requires long processing time. Here, we report a facile and remarkably rapid method for production of GQDs exhibiting excellent optoelectronic properties. We employed the pulsed laser ablation (PLA) technique to exfoliate GQDs from multi-wall carbon nanotube (MWCNTs), which can be referred to as a pulsed laser exfoliation (PLE) process. Strikingly, it takes only 6 min to transform all MWCNTs precursors to GQDs by using PLE process. Furthermore, we could selectively produce either GQDs or graphene oxide quantum dots (GOQDs) by simply changing the organic solvents utilized in the PLE processing. The synthesized GQDs show distinct blue photoluminescence (PL) with excellent quantum yield (QY) up to 12% as well as sufficient brightness and resolution to be suitable for optoelectronic applications. We believe that the PLE process proposed in this work will further open up new routes for the preparation of different optoelectronic nanomaterials.

Pulsed Laser Synthesis of Er3+/Yb3+ Co-Doped CaMoO4 Colloidal Nanocrystal and Its Upconversion Luminescence.

We report a novel synthetic route for Er3+Yb3+ co-doped calcium molybdate (CaMoO4) nanoparticles by pulsed laser ablation in ethanol. The crystalline phase, particle morphology, laser ablation mechanism and upconversion (UC) luminescent properties are investigated. Stable colloidal suspensions consisting of well-dispersed Er3+/Yb3+ co-doped CaMoO4 nanoparticles could be obtained without any surfactant. Under 980 nm excitation, Er3+/Yb3+ co-doped nanocolloidal CaMoO4 suspension had a weak red emission near 670 nm and strong green UC emissions at 530 and 550 nm, corresponding to the intra 4f transitions of Er3+ (4F(9/2), 2H(11/2), 4S(3/2)) --> Er3+ (4I(15/2)). The Er3+/Yb3+ co-doped nanocrystalline CaMoO4 suspension exhibited strong green emission visible to the naked eyes and a possible UC mechanism depending on the pump power dependence is discussed in detail.

Quasi-intrinsic colossal permittivity in Nb and In co-doped rutile TiO2 nanoceramics synthesized through a oxalate chemical-solution route combined with spark plasma sintering.

Nb and In co-doped rutile TiO2 nanoceramics (n-NITO) were successfully synthesized through a chemical-solution route combined with a low temperature spark plasma sintering (SPS) technique. The particle morphology and the microstructure of n-NITO compounds were nanometric in size. Various techniques such as X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), thermogravimetric (TG)/differential thermal analysis (DTA), Fourier transform infrared (FTIR), and Raman spectroscopy were used for the structural and compositional characterization of the synthesized compound. The results indicated that the as-synthesized n-NITO oxalate as well as sintered ceramic have a co-doped single phase of titanyl oxalate and rutile TiO2, respectively. Broadband impedance spectroscopy revealed that novel colossal permittivity (CP) was achieved in n-NITO ceramics exhibiting excellent temperature-frequency stable CP (up to 10(4)) as well as low dielectric loss (∼5%). Most importantly, detailed impedance data analyses of n-NITO compared to microcrystalline NITO (µ-NITO) demonstrated that the origin of CP in NITO bulk nanoceramics might be related with the pinned electrons in defect clusters and not to extrinsic interfacial effects.

Growth of Er3+/Yb3+ co-doped CaMoO4 thin film by a spray coating and its upconverting luminescence.

Polycrystalline Er3+/Yb3+ co-doped CaMoO4 (CaMoO4:Er3+/Yb3+) film was successfully fabricated by a spray coating method. Crystal structure, surface morphology and upconversion (UC) luminescent properties were investigated. Under 980-nm excitation, CaMoO4:Er3+/Yb3+ film exhibited strong green UC emissions at 530 and 550 nm (2H,11/2 --> 4S3/2 - 4I15/2) visible to the naked eye with a weak red emission near 660 nm (4F9/2 --> 4I15/2) corresponding to the intra 4f transitions of Er3+. A possible UC mechanism related to the pump-power dependence is discussed in detail.

Synthesis and photoluminescence of novel Ba9Y2Si6O24:Eu2+ green phosphor.

Novel (Ba1_xEu(x))9Y2Si6O24 green phosphors were successfully prepared by a solid-state reaction method. The prepared (Ba1_xEu(x))9Y2Si6O24 green phosphors showed a single intense broadband emission in a range from 502 to 510 nm. The effects of the Eu2+ doping concentration on the optical properties were discussed under consideration of concentration quenching. The experimental results clearly indicates that the prepared (Ba1_xEu(x))9Y2Si6O24 green phosphors have great potentials as a down-conversion green phosphor for white light emitting diodes (LEDs) utilizing blue LEDs as the primary light source.

Green lighting upconversion luminescence of Yb3+, Er3+ co-doped BaMoO4.

A green lighting upconversion (UC) system was successfully achieved from Er3+/Yb3+ co-doped BaMoO4 synthesized by the complex citrate-gel method. Under 980 nm laser excitation, the Er3+/Yb3+ co-doped BaMoO4 emitted strong green luminescence around 530 and 550 nm and weak red luminescence near 660 nm, which corresponded to the intra 4f-4f transitions in Er3+. Optimal doping concentrations of Er3+/Yb3+ into the BaMoO4 matrix were investigated. Moreover, based on excitation power dependence, the UC luminescent mechanism in the Er3+/Yb3+ co-doped BaMoO4 was presented in detail.

Pulsed-Laser-Induced Simple Synthetic Route for Tb(3)Al(5)O(12):Ce Colloidal Nanocrystals and Their Luminescent Properties.

Cerium-doped Tb(3)Al(5)O(12) (TAG:Ce(3+)) colloidal nanocrystals were synthesized by pulsed laser ablation (PLA) in de-ionized water and lauryl dimethylaminoacetic acid betain (LDA) aqueous solution for luminescent bio-labeling application. The influence of LDA molecules on the crystallinity, crystal morphology, crystallite size, and luminescent properties of the prepared TAG:Ce(3+) colloidal nanocrystals was investigated in detail. When the LDA solution was used, smaller average crystallite size, narrower size distribution, and enhanced luminescence were observed. These characteristics were explained by the effective role of occupying the oxygen defects on the surface of TAG:Ce(3+) colloidal nanocrystal because the amphoteric LDA molecules were attached by positively charged TAG:Ce(3+) colloidal nanocrystals. The blue-shifted phenomena found in luminescent spectra of the TAG:Ce(3+) colloidal nanocrystals could not be explained by previous crystal field theory. We discuss the 5d energy level of Ce(3+) with decreased crystal size with a phenomenological model that explains the relationship between bond distance with 5d energy level of Ce(3+) based on the concept of crystal field theory modified by covalency contribution.