Chemical synthesis of NdFeB/Fe-Co nanocomposite with high magnetic energy product.

NdFeB is one of the most popular permanent magnets (PMs) possessing the best energy product (BH) among the common PM materials. However, exchange-coupled nanocomposite magnets fabricated by embedding nanostructures of soft-phase magnetic materials into a hard-phase magnetic matrix manifest higher remanence and a higher energy product. Here we present the fabrication of exchange coupled NdFeB/Fe-Co magnetic nanocomposites using gel-combustion and diffusion-reduction processes.

Anisotropic characteristics and improved magnetic performance of Ca-La-Co-substituted strontium hexaferrite nanomagnets.

Recent studies on next-generation permanent magnets have focused on filling in the gap between rare-earth magnets and rare-earth-free magnets, taking into account both the cost-effectiveness and magnetic performance of the magnetic materials. As an improved rare-earth-free magnet candidate, here, Ca-substituted M-type Sr-lean hexaferrite particles within a nano- to micro-scale regime, produced using an ultrasonic spray pyrolysis method, are investigated. Theoretically, the maximum coercivity (H) can be achieved in submicron Sr-ferrite crystals (i.

Exchange-Coupling Interaction in Zero- and One-Dimensional SmCo/FeCo Core-Shell Nanomagnets.

Rare-earth-based core-shell spring nanomagnets have been intensively studied in the permanent magnet industry. However, the inherent agglomeration characteristics of zero-dimensional (0-D) magnetic nanoparticles are an issue in practical fabrication of magnetic nanocomposites due to deterioration in exchange-coupling interactions, resulting in inferior magnetic performance. Here, with an aim to overcome the structural limitations, we report a new type of SmCo/FeCo core-shell nanomagnet with a well-dispersed one-dimensional (1-D) structure prepared by a combination of electrospinning and electroless plating processes.

Near theoretical ultra-high magnetic performance of rare-earth nanomagnets via the synergetic combination of calcium-reduction and chemoselective dissolution.

Rare earth permanent magnets with superior magnetic performance have been generally synthesized through many chemical methods incorporating calcium thermal reduction. However, a large challenge still exists with regard to the removal of remaining reductants, byproducts, and trace impurities generated during the purifying process, which serve as inhibiting intermediates, inducing productivity and purity losses, and a reduction in magnetic properties. Nevertheless, the importance of a post-calciothermic reduction process has never been seriously investigated.

Development of an Anti-Corrosion Conductive Nano Carbon Coating Layer on Metal Bipolar Plates.

For automotive applications of polymer electrolyte membrane fuel cells, the enhancement of the corrosion resistance of metal bipolar plates has been a critical issue with regard to the lifespan of fuel cell stacks. In this paper, we present a novel method for increasing the lifespan by means of a conductive carbon coating on bipolar plates. Conductive carbon films were plasma coated onto metal bipolar plates in a vacuum at various temperatures.

Synthesis of Samarium-Cobalt Sub-micron Fibers and Their Excellent Hard Magnetic Properties.

High-throughput synthesis of Samarium-Cobalt sub-micron fibers with controlled composition and dimension was demonstrated by combining electrospinning and reduction-diffusion processes. The composition of fibers was readily varied (8 < Sm < 20 at.%) by adjusting precursor composition whereas the diameter of fibers was precisely controlled by varying electrospinning parameters (e.

Low-level laser therapy affects osseointegration in titanium implants: resonance frequency, removal torque, and histomorphometric analysis in rabbits.

Objectives: The purpose of this study was to investigate the effects of low-level laser therapy (LLLT) with a diode gallium-aluminum-arsenide (Ga-Al-As) low-level laser device on the healing and attachment of titanium implants in bone.

Materials And Methods: Thirteen New Zealand white male rabbits weighing 3.0±0.

Synthesis and Magnetic Properties of τ-MnAlC Powders.

In order to improve the hard magnetic properties of MnAl alloy, it is critical to fabricate fine τ phase MnAl powders. In addition, a rapid cooling process and an addition of stabilization elements are required to fabricate a homogeneous phase because a τ phase is a metastable structure. In this study, τ-Mn54Al(46-x)C(x) (x = 0, 1, 2) powders were prepared by melt-spinning and subsequent annealing and milling processes.

Enhancement of the Remanence Value of Bulk Strontium Ferrite by the Addition of AlNiCo.

Increasing the remanence value of bulk permanent magnets is a critical issue to increase their maximum energy product ((BH)(max)) value. Currently, the enhancement of magnetic alignment is known to come close to the engineering limit. In this study, we investigated the effect of a magnetic layered structure on the remanence value using strontium ferrite and AlNiCo.

Effects of Different Salts on Salt-Assisted Ultrasonic Spray Pyrolysis (SA-USP) Calcination for the Synthesis of Strontium Ferrite.

Strontium ferrite (hexaferrite), SrFe12O19, was successfully fabricated in sizes ranging from hundreds of nanometers to several micrometers by salt-assisted ultrasonic spray pyrolysis-calcination using different salt media. All samples were single phases of SrFe12O19 without the intermediate phase, α-Fe2O3, and their morphology was hexagonal. As calcination temperature increased, the size of as-calcined samples and saturation magnetization, Ms, increased while coercivity decreased.

Stability of Le Fort I Osteotomy With Propeller Graft for Canting Correction in Facial Asymmetry.

The aim of this study was to evaluate the maxillary stability in patients who had undergone Le Fort I osteotomy with propeller graft and mandibular sagittal split ramus osteotomy for correction of maxillary asymmetry. This was a retrospective study on 15 facial asymmetry patients (7 men, 8 women: 22.2 years) requiring surgical correction at the preoperative (T0), immediately postoperative (T1) and 6 months after surgery (T2) stages.

Stability of unilateral sagittal split ramus osteotomy for correction of facial asymmetry: long-term case series and literature review.

Bilateral sagittal split ramus osteotomy is considered a standard technique in mandibular orthognathic surgeries to reduce unexpected bilateral stress in the temporomandibular joints. Unilateral sagittal split ramus osteotomy (USSO) was recently introduced to correct facial asymmetry caused by asymmetric mandibular prognathism and has shown favorable outcomes. If unilateral surgery could guarantee long-term postoperative stability as well as favorable results, operation time and the incidence of postoperative complications could be reduced compared to those in bilateral surgery.

Human umbilical cord blood-derived CD34-positive endothelial progenitor cells stimulate osteoblastic differentiation of cultured human periosteal-derived osteoblasts.

The aim of this study was to examine the effects of human umbilical cord blood-derived CD34-positive endothelial progenitor cells (CD34+ EPCs) on osteoblastic differentiation of cultured human periosteal-derived osteoblasts (POs). CD34+ cells from human umbilical cord blood were sorted to purify more EPCs in characterization. These sorted cells showed CD31, VE-cadherin, and KDR expression as well as CD34 expression and formed typical tubes in Matrigel.

JNK signaling plays an important role in the effects of TNF-α and IL-1β on in vitro osteoblastic differentiation of cultured human periosteal-derived cells.

The purpose of this study was to examine the effects of TNF-α and IL-1β on in vitro osteoblastic differentiation of cultured human periosteal-derived cells. To examine the effects of TNF-α and IL-1β on in vitro osteoblastic differentiation of cultured human periosteal-derived cells, the cells cultured in the osteogenic induction medium were treated with 0.1-10 ng/ml TNF-α and 0.

New bimaxillary orthognathic surgery planning and model surgery based on the concept of six degrees of freedom.

The aim of this paper was to propose a new method of bimaxillary orthognathic surgery planning and model surgery based on the concept of 6 degrees of freedom (DOF). A 22-year-old man with Class III malocclusion was referred to our clinic with complaints of facial deformity and chewing difficulty. To correct a prognathic mandible, facial asymmetry, flat occlusal plane angle, labioversion of the maxillary central incisors, and concavity of the facial profile, bimaxillary orthognathic surgery was planned.

Generation of osteogenic construct using periosteal-derived osteoblasts and polydioxanone/pluronic F127 scaffold with periosteal-derived CD146 positive endothelial-like cells.

The purpose of this study was to generate tissue-engineered bone using human periosteal-derived osteoblasts (PO) and polydioxanone/pluronic F127 (PDO/pluronic F127) scaffold with preseeded human periosteal-derived CD146 positive endothelial-like cells (PE). PE were purified from the periosteal cell population by cell sorting. One of the important factors to consider in generating tissue-engineered bone using osteoprecursor and endothelial cells and a specific scaffold is whether the function of osteoprecursor and endothelial cells can be maintained in originally different culture medium conditions.

Synthesis of air stable iron nanopowders with various methods.

Magnetic properties and microstructures of iron-based nanopowders fabricated by several methods, such as sol-gel, thermal decomposition, and self-propagating combustion methods, were investigated. During a subsequent reduction annealing, added aluminum atoms formed coherent oxide shells with a hercynite structure around iron cores in all the nanopowders. In particular, the nanopowders synthesized by the self-propagating combustion method showed the highest saturation magnetization of 175.

Tissue-engineered bone formation using periosteal-derived cells and polydioxanone/pluronic F127 scaffold with pre-seeded adipose tissue-derived CD146 positive endothelial-like cells.

The aim of this study was to generate tissue-engineered bone formation using periosteal-derived cells seeded into a polydioxanone/pluronic F127 (PDO/Pluronic F127) scaffold with adipose tissue-derived CD146 positive endothelial-like cells. Considering the hematopoietic and mesenchymal phenotypes of adipose tissue-derived cells cultured in EBM-2 medium, CD146 positive adipose tissue-derived cells was sorted to purify more endothelial cells in characterization. These sorted cells were referred to as adipose tissue-derived CD146 positive endothelial-like cells.

Three-dimensional analysis of midfacial soft tissue changes according to maxillary superior movement after horizontal osteotomy of the maxilla.

Three-dimensional diagnostic and treatment planning is a promising means of improving orthognathic surgical results from the standpoint of facial aesthetics. In such planning, cone-beam computed tomography is a useful tool. The purpose of the present study was to evaluate three-dimensional soft tissue changes in the midfacial region, with specific reference to post-Le Fort I osteotomy maxillary superior movement.

Vascular endothelial growth factor stimulates osteoblastic differentiation of cultured human periosteal-derived cells expressing vascular endothelial growth factor receptors.

Angiogenesis plays an important role in bone development and postnatal bone fracture repair. Vascular endothelial growth factor (VEGF) and vascular endothelial growth factor receptors (VEGFRs) are primarily involved in angiogenesis. This study investigated the expression of VEGF isoforms, VEGFR-1, and VEGFR-2 during the osteoblastic differentiation of cultured human periosteal-derived cells.

Osteogenic differentiation of human periosteal-derived cells in a three-dimensional collagen scaffold.

This study examined the osteogenic differentiation of cultured human periosteal-derived cells grown in a three dimensional collagen-based scaffold. Periosteal explants with the appropriate dimensions were harvested from the mandible during surgical extraction of lower impacted third molar. Periosteal-derived cells were introduced into cell culture.

In vitro osteogenic differentiation of cultured human dental papilla-derived cells.

Purpose: This study examined the osteogenic phenotypes and mineralization of cultured human dental papilla-derived cells.

Materials And Methods: Dental papillae were harvested from mandibles during surgical extraction of lower impacted third molars from 3 patients aged 13 to 15 years. The dental papilla-derived cells were introduced into the cell culture.

Expression of receptor activator of nuclear factor -kappaB ligand, receptor activator of nuclear factor -kappaB, and osteoprotegerin, following low-level laser treatment on deproteinized bovine bone graft in rats.

The aim of this study was to investigate by immunohistochemistry the effects of low-level laser (LLL) irradiation on the expression of the receptor activator of nuclear factor -kappaB ligand (RANKL), osteoprotegerin (OPG), and the receptor activator of nuclear factor -kappaB (RANK) in deproteinized bovine bone grafts in rats. Twenty-four male Sprague-Dawley rats aged 15 weeks were allocated to either an experimental group that underwent LLL irradiation during bone healing at the bone graft sites of the rats' calvarial bone defects or a control group. In the experimental group, gallium-aluminum-arsenide (Ga-Al-As) diode LLL (wavelength 808 nm; output 96 mW) was used to irradiate three areas on and around bone defects.

Vascular endothelial growth factor expression in cultured periosteal-derived cells.

The purpose of this study was to examine the expression of vascular endothelial growth factor (VEGF) during osteoblastic differentiation of cultured human periosteal-derived cells. Periosteal tissues were obtained from mandible during surgical extraction of lower impacted third molars. Periosteal-derived cells were introduced into cell culture.