Novel Technique For Fabrication Research Articles

MRI Modeling for 3D Printed Fabrication of Nasoalveolar Molding Appliance in Patients With Cleft Lip and Palate

Purpose: Present a novel technique for fabrication of nasoalveolar molding (NAM) appliances for neonates with cleft lip and palate (CLP) using magnetic resonance imaging (MRI). Study design: Proof-of-concept study. Setting/Participants: One patient with unilateral CLP was recruited for participation in this study at our institution. Interventions: This study employed 2 different methods for creating a NAM appliance, which is used in patients with CLP to improve anatomic positioning of the orofacial cleft in preparation for primary cheiloplasty. The patient underwent intraoral impression for traditional fabrication of a NAM appliance (PMMA-NAM) and also MRI of the face for digital fabrication of a NAM appliance (CAD-NAM). The 2 appliances were then compared using landmarks for measurements. Primary Outcome: Landmark measurements on NAM appliances; Clinical interchangeability of NAM appliances. Results: There was a statistically significant difference in the external arch width between the CAD-NAM and the PMMA-NAM. All other NAM measurements were statistically similar. Additionally, there was clinical success in the interchangeable fit of both appliances on both models. Conclusions: This technique could potentially eliminate the need for creation of an intraoral impression, as well as the adverse events associated with this, in the fabrication of NAM appliances. Larger studies are necessary to further define the efficacy of this novel approach and generalizability to other patients with CLP.

A novel technique for fabrication of rod-like shape zeolite LTA and hydroxysodalite by extrusion of bentonite powder: Effects of technical factors on structural characteristics

The current investigation proposes a novel method for the fabrication of zeolite-based packed beds by extrusion of a paste, containing Ca-bentonite, boehmite, and sodium hydroxide, as rod-like shape. The formed precursor was heated at 800 °C to reinforce the extrudates, aged at different times, 3–24 h, and converted to the zeolite structure by recrystallization in the hydrothermal condition, 3–9 h. The obtained results showed that aging, and recrystallization times affect the crystalline phase structure, morphology of particles, textural properties, and cation exchange capacity (CEC) as characterized by X-ray diffractometry, field emission electron microscopy, and N2 adsorption–desorption isotherms. The thermally treated extrudates could be converted to zeolite LTA, and or hydroxysodalite (HS), depending on aging, and recrystallization times. It is necessary to age the treated extrudates in 9 h, and control the recrystallization time within 3 h to achieve zeolite LTA with a proper CEC, 232 mg g−1. Contrarily, the choice of inverse conditions, leads to create a mesoporous HS with a broad pore size distribution, 2–50 nm.

A Novel Technique for Fabrication of Hollow Obturator for a Maxillary Defect: A Case Report

Prosthodontic rehabilitation following aggressive infections and malignancies is challenging. Surgical intervention may lead to anatomical defects resulting in oro-antral communication that causes difficulty in mastication, deglutition, impaired speech and facial disfigurement. The role of a Prosthodontist in maxillary defects is to restore these defects with the fabrication of obturators. However, the extent of the obturator into these large defects necessitate bulkier, heavy prosthesis which would likely be nonretentive and uncomfortable for the patient. Hollow bulb obturators are fabricated to reduce the weight of these prostheses. The method of fabrication of hollow bulb obturators with lost salt technique in the maxillary defect is described in this case report.

Novel technique for fabrication of n-type crystalline silicon selective emitter for solar cell processing

A new way of realizing crystalline silicon selective emitter by simultaneous formation of front side selective emitter as well as rear back surface field (BSF) layer in rear side diffusion step has been presented in this work. In this paper, we have demonstrated a novel technique to achieve a selective emitter having a highly diffused region with lower sheet resistance around 30–32 Ω sq−1 along with peak doping concentration 7.34 × 1019 atoms cm−3, junction depth around 0.97 μm and lightly diffused region with higher sheet resistance around 78–80 Ω sq−1 along with peak doping concentration 4.57 × 1019 atoms cm−3, junction depth around 0.64 μm. These results show that selective emitter has been formed in single diffusion process without any extra heat treatment and chemical etching process, thus this process becomes cost effective.

Novel technique for fabrication of electrospun membranes with high hydrophobicity retention

In a bid to mitigate the problem of pore wetting in membrane distillation, a superhydrophobic membrane was prepared by in situ deposition of teflon oligomer microparticles on poly (vinylidenefluoride-co-hexafluoropropylene) nanofibers during electrospinning. This new approach relies on dusting in the chamber where the threads of polymer solution are spun in the zone of fiber transition between liquid to solid. In addition to distributing the particles across the electrospun mat, the novel technique allows bonding of the particles to the solidified fibers. The prepared membrane was characterized and tested in direct contact membrane distillation (DCMD). The results show that the membrane, which was about 30 μm thick, was superhydrophobic and displayed a water contact angle of 155 ± 1°. The membrane also supported a contact angle of 153 ± 1° for a 3 mM SDS solution having lower surface tension (49 mN/m) than water (72 mN/m). The membrane had nominal and maximum pore diameters of 0.57 μm and 1.93 μm respectively, and was about 91% porous. The membrane also supported a liquid entry pressure of about 22 psi. Furthermore, the membrane gave average permeate fluxes of 7 kg m−2 h−1, 10 kg m−2 h−1 when tested in DCMD at 60 °C and 70 °C feed temperatures respectively, with a salt rejection of 99.97%. Finally, the membrane supported a water contact angle of 140 ± 1° after it had been used in DCMD test, while the mean pore diameter, maximum pore diameter and porosity decreased to 0.32 μm, 0.83 μm and 86.5% respectively after test.

OSC12: Dual Stent to Stabilize Implant Hand Piece.

Introduction: The limited access and visibility, along with proximity of the mandibular canal or maxillary sinus in the posterior region of alveolar ridge makes it difficult to place the implant in ideal angulation. This may lead to imprecise prosthetic rehabilitation due to the extreme angulations and misalignments incurred in the arch of placement. Using a surgical stent designed based on the diagnostic wax up could eliminate most of the clinical and laboratory complications. Discussion: In this article we are describing a novel technique for fabrication of a stent with dual assembly which helps the implantologist to place implant in predetermined position and angulation in posterior inaccessible areas. This stent guides the head of the hand piece by which the determined path of osteotomy is maintained. Since it is a dual assembly it could be easily inserted in the patient’s with reduced oral orifices. Conclusion: This article provides a description about a technique which helps the implantologist to precisely position the implant effortlessly even in less accessible areas. The implant osteotomy in the posterior maxillary region becomes effortless and more precise using the dual assembly stent. The technique allows the hand piece to be stabilized throughout the osteotomy and hence positioning of the implant in the predetermined angulation without any error.

Novel laser-processed CsI:Tl detector for SPECT

The aim of this work is to demonstrate the feasibility of a novel technique for fabrication of high spatial resolution CsI:Tl scintillation detectors for single photon emission computed tomography systems. The scintillators are fabricated using laser-induced optical barriers technique to create optical microstructures (or optical barriers) inside the CsI:Tl crystal bulk. The laser-processed CsI:Tl crystals are 3, 5, and 10 mm in thickness. In this work, the authors focus on the simplest pattern of optical barriers in that the barriers are created in the crystal bulk to form pixel-like patterns resembling mechanically pixelated scintillators. The monolithic CsI:Tl scintillator samples are fabricated with optical barrier patterns with 1.0 × 1.0 mm(2) and 0.625 × 0.625 mm(2) pixels. Experiments were conducted to characterize the fabricated arrays in terms of pixel separation and energy resolution. A 4 × 4 array of multipixel photon counter was used to collect the scintillation light in all the experiments. The process yield for fabricating the CsI:Tl arrays is 100% with processing time under 50 min. From the flood maps of the fabricated detectors exposed to 122 keV gammas, peak-to-valley (P/V) ratios of greater than 2.3 are calculated. The P/V values suggest that regardless of the crystal thickness, the pixels can be resolved. The results suggest that optical barriers can be considered as a robust alternative to mechanically pixelated arrays and can provide high spatial resolution while maintaining the sensitivity in a high-throughput and cost-effective manner.

Nanopatterning of Suspended Graphene Films by Local Catalytic Etching Using Atomic Force Microscopy Equipped with an Ag-Coated Probe

We have developed a novel technique for fabrication of nanopores in suspended graphene (SG) films using atomic force microscopy (AFM) equipped with a catalytic Ag-coated probe. By applying voltages between an Ag-coated tip and SG films in tapping mode AFM under ambient conditions at room temperature, Ag nanoparticles on the tip contact to the graphene surface, and simultaneously local Joule heating is generated at the tip–Ag nanoparticle–graphene contact. As a result, the SG films can be etched via oxidation assisted by the heated Ag catalytic nanoparticles, forming a nanopore. Because the hole shape and size on the SG films depend on the shape of the AFM tip, we can regulate the patterns on the graphene films by optional AFM tips.

Electrodiffusion Method of Near-Wall Flow Diagnostics in Microfluidic Systems

The electrodiffusion technique has been mostly used for the near-wall flow diagnostics on large scales. A novel technique for fabrication of plastic microfluidic systems with integrated metal microelectrodes (called technique of sacrificed substrate) enables us to produce microfluidic devices with precisely shaped sensors for wall shear stress measurements. Several micrometer thick gold sensors, which are built-in a plastic substrate, exhibit good mechanical resistance and smoothness. Proper functioning of prepared chips with microsensors has been first tested in various calibration experiments (polarization curve, sensor response to polarization set-up, steady flow calibration, temperature dependence of diffusivity). Our first results obtained for separating/reattaching flow behind a backward-facing step and for gas-liquid Taylor flow in microchannels then demonstrate its applicability for the detection of near-wall flow reversal, the delimitation of flow - recirculation zones, and the determination of wall shear stress response to moving bubbles. Other applications of these sensors in microfluidics (e.g. characterization of liquid films, capillary waves, bubbles or drops) can be also envisaged.

Modified Friction Stir Channeling: A Novel Technique for Fabrication of Friction Stir Channel

Friction stir channeling (FSC) is a simple method for fabrication of a continuous, integral channel in a monolithic plate, which is carried out in a single pass. The fabricated channels can be applied in heat exchanger industry. In this study, a novel technique was introduced to produce channels in 6061 aluminum alloy which is named as Modified Friction Stir Channeling (MFSC). This technique is derived from Friction stir processing. In this technique, the tool profile and position of tool pin against work piece were designed differently from FSC process. Channels were fabricated with a very regular shape such as rectangular. Comparison between MFSC and FSC showed that fabricated channels, using MFSC process, had better properties relative to fabricated channels by FSC.

Resistance Heated Pressing (RHP): A Novel Technique for Fabrication of Titanium Alloys

A novel powder metallurgical technique for the fabrication of titanium alloys has been developed by utilizing a pressure-assisted, resistance-heating sintering technique. In this technique, the high electrical resistance of oxide layers present on the surface of powder particles has been exploited to ensure effective resistance heating of green compacts. Ti-6Al-4V pre-alloyed powders of 100 µm size were compressed while being heated under a variety of conditions of sintering temperature, pressure and time. The outcomes of our experiments have proven that resistance heating can be a very effective means of heating during powder consolidation. The results have indicated that the required sintering time and temperature in the new resistance-heated sintering technique are much reduced in compared to sinter-press and/or hot isostatic pressing techniques, resulting in a refined microstructure with a concomitant improvement in mechanical properties.

A novel technique for fabrication of micro- and nanofluidic device with embedded single carbon nanotube

This paper describes a novel technique for fabrication of micro- and nanofluidic device that consists of a carbon nanotube (CNT) and a polydimethylsiloxane (PDMS) microchannel. Single CNT was placed at desired locations using dielectrophoresis (DEP) and PDMS microchannel was constructed on the aligned CNT via photolithography and soft lithography techniques. This technique enables a CNT to be seamlessly embedded in a PDMS microchannel. Moreover, controlling the PDMS curing condition enables the construction of the device with or without a CNT (the device without CNT has a trace nanochannel in PDMS). Preliminary flow tests such as capillary effect and pressure-driven flow were performed with the fabricated devices. In the capillary effect tests, the flow stopped at the nanochannel in both devices. In the pressure-driven flow lower flow resistance was observed in the device with a CNT.

Metal electrodes in plastic microfluidic systems

We have developed a novel technique for fabrication of plastic microfluidic systems with integrated metal microelectrodes. This technique includes: (i) optical lithography in the ma-P1275 photoresist previously coated on a metal substrate, (ii) electroplating of gold or copper, (iii) photoresist stripping, (iv) embedding of the metal structures in the UV curable resin Acrifix 192 ®, (v) UV curing of the resin, (vi) removal of the metal substrate – by peeling off or etching, and (vii) thermal bonding of the embedded electrodes to a mate with fluidic structures. Relatively high thickness of the metal structures built-in in the curable resin provides for a high mechanical stability of such structures. The fabrication procedure was successfully tested in the fabrication of microfluidic devices for three different applications: (i) an electrochemical microfluidic system called “electrolyte diode”, (ii) A microfluidic system with an embedded cation exchange membrane, and (iii) AC and DC electroosmotic micropumps with arrays of metal electrodes.

Fabrication of novel anisotropic magnetic microparticles

We report a novel technique for fabrication of magnetically anisotropic microparticles based on “arresting” of the alignment of oleic acid coated magnetite nanoparticles (OCMNs) dispersed within the oil drops of a polymerisable oil-in-water emulsion. This was achieved by polymerising the oil drops after gelling the continuous aqueous phase in the presence of an external magnetic field. This approach allowed us to produce magnetic Janus particles with anisotropic optical and magnetic properties which form unusual zig-zag chains and structures when exposed to an external magnetic field. We studied the magnetic properties of these novel microparticles and showed that they retained remanence magnetisation with high coercivity values indicative of ferromagnetic behaviour. This indicates that the composite polymeric Janus microparticles posses a net magnetic dipole and behave like micromagnets due to the “arrested” orientation of the OCMNs in their polymeric matrix. Utilizing the same technique, magnetic Janus microparticles have been prepared based on emulsions stabilised only by OCMNs without the use of surfactants, and the effect of pH of continuous aqueous phase on the morphology of these microparticles has been investigated.

Fabrication of Novel Magnetic Janus Microparticles

ABSTRACTWe have designed a novel technique for fabrication of magnetic Janus microparticles based on “trapping” the alignment of magnetite nanoparticles dispersed within the oil drops of polymerizable oil-in-water emulsion. We polymerized the oil drops after gelling the continuous aqueous phase in the presence of an external magnetic filed. This allowed us to produce magnetic Janus particles with optical and magnetic anisotropy which form unusual zigzag chains and structures when an external magnetic field is applied to a suspension of such particles. These novel microparticles retain high remanence magnetization and coercivity values indicative of ferromagnetic behavior, which indicates that the composite polymeric Janus microparticles posses a net magnetic dipole and behave like micro-magnets due to the “trapped” orientation of the magnetite nanoparticles in their polymeric matrix.

Novel Technique for Fabrication of Nanoparticle Structures in KNbO3–TeO2 Glass for Photonic Integrated Circuits

We succeeded in fabricating novel nanoparticle structures on KNbO3–TeO2 glass induced by ultraviolet (UV) laser irradiation and found that the size and size distribution could be controlled by the conditions of laser irradiation, such as fluence, pulse repetition rate, and the temperature of the glass specimen by heat assistance (HA). Nano-sized particles are an interesting new material, because they will be able to open the door to the invention of photonic circuits of extremely small size, which transfer optical signals through optical near-field energy operating by a completely different principle. The particle diameters may be controlled from approximately 200 nm up to 500 nm by modifications of UV laser fluence and the repetition rate of pulses. When using HA with a glass specimen during laser irradiation, it has been found that nanoparticle formation is activated and particle size increased as the temperature of the glass increased, and the uniformity of particle size is markedly improved by HA treatment. The standard deviation of particle size is 20 nm at 100 °C. A 60% improvement in the size variation of particles is possible in comparison with laser irradiation without HA. These results suggest that heat is involved in nanoparticle formation during UV laser irradiation, which means that the overall history of heating with pulsed laser irradiation is critically important to control the form of the particles. Furthermore, periodic structures with an 800 nm pitch constructed by lines of ordered nanoparticles with diameters of approximately 150–300 nm were successfully fabricated by laser irradiation through a phase mask. This is a significant advancement towards the realization of nanophotonic circuits.

A new fabrication process for a flexible skin with temperature sensor array and its applications

This paper reports a novel technique for fabrication of a flexible skin with a temperature sensor array (40×1 sensors). A simplified MEMS technology using platinum resistors as sensing materials, which are sandwiched between two polyimide layers as flexible substrates is developed. The two polyimide layers are deposited on top of a thin aluminum layer, which serves as a sacrificial layer such that the flexible skin can be released by metal etching and peeled off easily. The flexible skin with a temperature sensor array has a high mechanical flexibility and can be handily attached on a highly curved surface to detect tiny temperature distribution inside a small area. The sensor array shows a linear output and has a sensitivity of 7.5 mV/°C (prior to amplifiers) at a drive current of 1 mA. To demonstrate its applications, two examples have been demonstrated, including measurement of temperature distribution around a micro heater of a micro PCR (polymerase chain reaction) chip for DNA amplification and detection of separation point for flow over a circular cylinder. The development of the flexible skin with a temperature sensor array may be crucial for measuring temperature distribution on any curved surface in the fields of aerodynamics, space exploration, auto making and biomedical applications etc.

A novel technique for fabrication of near-net-shape CMCs

A sol-gel vacuum infiltration technique has been developed for the fabrication of near-net-shape ceramic matrix composites (CMCs) using discontinuous mullite fibre preform with 15 vol.% of fibre content and ZrO2.10 wt.% Y2O3 sol as the infiltrant. Effect of sol viscosity, number of infiltration and calcination temperature on physico-mechanical properties of fabricated CMCs were examined. Characterization of the fibre preform, matrix material (in the form of ceramic specimen without fibre) and the developed CMCs were performed by X-ray diffraction (XRD) and scanning electron microscopy (SEM). XRD indicated the presence of cubic (c) and tetragonal (t) zirconia in both the CMCs and the ceramic specimens calcined even at 1400°C. Flexural strength of the CMCs and the ceramic specimens (calcined at 1400°C), determined by the three-point bending test, was found to be about 14 mPa and 1.40 mPa, respectively. SEM indicated multiple fracture of the matrix which gave rise to pseudo elasticity. This is also evident from the load-displacement curve of the three-point bend test. SEM studies also indicated fibre pull-out in the fracture surface of the CMCs.

Large-scale synthesis of ultrafine Si nanoparticles by ball milling

Si nanoparticles have been synthesized by ball-milling of graphite and SiO 2 powders. The solid-phase reaction, C(graphite)+SiO 2→Si+CO 2, was found to be a novel technique for fabrication of ultrafine Si particles. The reduced Si in the powder assembled as nanoparticles with a wide range of diameters. Multiple-peak structures were observed in the photoluminescence spectra of the Si nanoparticles at room temperature. The peak energies were found to coincide with the PL peak pinning energies previously reported in porous Si. Thus, the fine structures of luminescence spectra could be attributed to the size quantization of the Si nanoparticles formed via solid-phase reaction during ball-milling.

Formation of Silver Nanowires by a Novel Solid−Liquid Phase Arc Discharge Method

A novel technique for fabrication of silver nanowires was successfully developed via a so-called solid−liquid phase arc discharge method (SLPAD). It was found that the aging time following the SLPAD method has a significant effect on the formation and growth of silver nanowires. The possible formation process of the silver nanowires was proposed. The present technique may be extended for preparation of other metal nanowires.