WorldWideScience

Sample records for fabrication process diseno

  1. Design of the ME-I powder mixer. Report of the design and construction of the powder mixer, according to the safety requisites of the pellets fabrication process; Diseno de mezclador de polvo ME-I. Reporte del diseno y construccion del mezclador de polvos, de acuerdo a los requisitos de seguridad del proceso de fabricacion de pastillas

    Energy Technology Data Exchange (ETDEWEB)

    Mariano H, E

    1991-03-15

    In order to fulfill the requirements of preparation of powder of UO{sub 2}; according to procedure P-M-PP-01, rev. 0, for the process of production of pellets, it was designed and manufactured a powders mixer to incorporate the lubricant one (zinc stearate) to the powder of UO{sub 2}. This equipment allows to mix the powder of UO{sub 2} evenly with the one zinc stearate, without forming considerable quantities of fine of UO{sub 2}, besides a sure control for the operators of the process and an easy access to the mixer to inspect the mixture. (Author)

  2. Mask fabrication process

    Science.gov (United States)

    Cardinale, Gregory F.

    2000-01-01

    A method for fabricating masks and reticles useful for projection lithography systems. An absorber layer is conventionally patterned using a pattern and etch process. Following the step of patterning, the entire surface of the remaining top patterning photoresist layer as well as that portion of an underlying protective photoresist layer where absorber material has been etched away is exposed to UV radiation. The UV-exposed regions of the protective photoresist layer and the top patterning photoresist layer are then removed by solution development, thereby eliminating the need for an oxygen plasma etch and strip and chances for damaging the surface of the substrate or coatings.

  3. Quality in the fabrication process

    International Nuclear Information System (INIS)

    Romano, A.; Aguirre, F.

    2010-01-01

    Enusa commitment to quality in the manufacture process materializes in the application of the most advanced product quality control technologies such as not-destructive inspection techniques, like artificial vision, X-ray or UT inspection, or process parameter statistical control systems. Quality inspectors are trained and certified by the main National Quality Organizations and receive periodic training under a formal company training program that constantly updates their qualification. Fabrication quality control reliability is based on a strategy that prioritizes redundancy of critical inspection equipment's and inspection personnel knowledge polyvalence. Furthermore, improvement in fabrication quality is obtained by a systematic application of the six sigma methodology where added value is created in projects integrating crosscutting company knowledge, reinforcing the global company vision that the fuel business is based on quality. (Author)

  4. Experimental Setup to Characterize Bentonite Hydration Processes; Diseno experimental para la caracterizacion de los procesos de hidratacion de la bentonita

    Energy Technology Data Exchange (ETDEWEB)

    Bru, A.; Casero, D.; Pastor, J.M.

    2001-07-01

    We present an experimental setup to follow-up the hydration process of a bentonite. Clay samples, of 2 cm x 12 cm x 12 cm, were made and introduced in a Hele-Shaw cell with two PMM windows and two steel frames. In hydration experiments, a fluid enters by an orifice in the frame, located both at the top and the bottom of the cell, to perform hydration in both senses. To get a uniform hydration we place a diffuser near the orifice. Volume influxes in hydration cells are registered in time. The evolution of the developed interface was recorded on a videotape. The video cameras was fixed to a holder so that the vertical direction in the monitor was the same as the direction of the larger extension of the cell. (Author) 6 refs.

  5. Polymer micromold and fabrication process

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Abraham P. (1428 Whitecliff Way, Walnut Creek, CA 94596); Northrup, M. Allen (923 Creston Rd., Berkeley, CA 94708); Ahre, Paul E. (1299 Gonzaga Ct., Livermore, CA 94550); Dupuy, Peter C. (1736 Waldo Ct., Modesto, CA 95358)

    1997-01-01

    A mold assembly with micro-sized features in which the hollow portion thereof is fabricated from a sacrificial mandrel which is surface treated and then coated to form an outer shell. The sacrificial mandrel is then selectively etched away leaving the outer shell as the final product. The sacrificial mandrel is fabricated by a precision lathe, for example, so that when removed by etching the inner or hollow area has diameters as small as 10's of micros (.mu.m). Varying the inside diameter contours of the mold can be accomplished with specified ramping slopes formed on the outer surface of the sacrificial mandrel, with the inside or hollow section being, for example, 275 .mu.m in length up to 150 .mu.m in diameter within a 6 mm outside diameter (o.d.) mold assembly. The mold assembly itself can serve as a micronozzle or microneedle, and plastic parts, such as microballoons for angioplasty, polymer microparts, and microactuators, etc., may be formed within the mold assembly.

  6. Polymer micromold and fabrication process

    Energy Technology Data Exchange (ETDEWEB)

    Lee, A.P.; Northrup, M.A.; Ahre, P.E.; Dupuy, P.C.

    1997-08-19

    A mold assembly is disclosed with micro-sized features in which the hollow portion thereof is fabricated from a sacrificial mandrel which is surface treated and then coated to form an outer shell. The sacrificial mandrel is then selectively etched away leaving the outer shell as the final product. The sacrificial mandrel is fabricated by a precision lathe, for example, so that when removed by etching the inner or hollow area has diameters as small as 10`s of micros ({micro}m). Varying the inside diameter contours of the mold can be accomplished with specified ramping slopes formed on the outer surface of the sacrificial mandrel, with the inside or hollow section being, for example, 275 {micro}m in length up to 150 {micro}m in diameter within a 6 mm outside diameter (o.d.) mold assembly. The mold assembly itself can serve as a micronozzle or microneedle, and plastic parts, such as microballoons for angioplasty, polymer microparts, and microactuators, etc., may be formed within the mold assembly. 6 figs.

  7. Fabrication Process Development for Light Deformable Mirrors

    Data.gov (United States)

    National Aeronautics and Space Administration — The project objective is to develop robust, reproductibble fabrication processes to realize functional deformable membrane mirrors (DM) for a space mission in which...

  8. Micro and nano fabrication tools and processes

    CERN Document Server

    Gatzen, Hans H; Leuthold, Jürg

    2015-01-01

    For Microelectromechanical Systems (MEMS) and Nanoelectromechanical Systems (NEMS) production, each product requires a unique process technology. This book provides a comprehensive insight into the tools necessary for fabricating MEMS/NEMS and the process technologies applied. Besides, it describes enabling technologies which are necessary for a successful production, i.e., wafer planarization and bonding, as well as contamination control.

  9. Superconducting materials fabrication process and products obtained

    International Nuclear Information System (INIS)

    Dubois, B.; Odier, P.

    1989-01-01

    A fabrication process of a fine superconducting powder easy to sinter is claimed. It consists in thermal treatment of an aerosol containing an organic and/or inorganic salt and/or a hydroxide of a rare earth, an alkaline earth metal and a transition metal in a ratio corresponding to the stoichiometry of the superconducting materials [fr

  10. Simple process to fabricate nitride alloy powders

    International Nuclear Information System (INIS)

    Yang, Jae Ho; Kim, Dong-Joo; Kim, Keon Sik; Rhee, Young Woo; Oh, Jang-Soo; Kim, Jong Hun; Koo, Yang Hyun

    2013-01-01

    Uranium mono-nitride (UN) is considered as a fuel material [1] for accident-tolerant fuel to compensate for the loss of fissile fuel material caused by adopting a thickened cladding such as SiC composites. Uranium nitride powders can be fabricated by a carbothermic reduction of the oxide powders, or the nitriding of metal uranium. Among them, a direct nitriding process of metal is more attractive because it has advantages in the mass production of high-purity powders and the reusing of expensive 15 N 2 gas. However, since metal uranium is usually fabricated in the form of bulk ingots, it has a drawback in the fabrication of fine powders. The Korea Atomic Energy Research Institute (KAERI) has a centrifugal atomisation technique to fabricate uranium and uranium alloy powders. In this study, a simple reaction method was tested to fabricate nitride fuel powders directly from uranium metal alloy powders. Spherical powder and flake of uranium metal alloys were fabricated using a centrifugal atomisation method. The nitride powders were obtained by thermal treating the metal particles under nitrogen containing gas. The phase and morphology evolutions of powders were investigated during the nitriding process. A phase analysis of nitride powders was also part of the present work. KAERI has developed the centrifugal rotating disk atomisation process to fabricate spherical uranium metal alloy powders which are used as advanced fuel materials for research reactors. The rotating disk atomisation system involves the tasks of melting, atomising, and collecting. A nozzle in the bottom of melting crucible introduces melt at the center of a spinning disk. The centrifugal force carries the melt to the edge of the disk and throws the melt off the edge. Size and shape of droplets can be controlled by changing the nozzle size, the disk diameter and disk speed independently or simultaneously. By adjusting the processing parameters of the centrifugal atomiser, a spherical and flake shape

  11. Inverted process for graphene integrated circuits fabrication.

    Science.gov (United States)

    Lv, Hongming; Wu, Huaqiang; Liu, Jinbiao; Huang, Can; Li, Junfeng; Yu, Jiahan; Niu, Jiebin; Xu, Qiuxia; Yu, Zhiping; Qian, He

    2014-06-07

    CMOS compatible 200 mm two-layer-routing technology is employed to fabricate graphene field-effect transistors (GFETs) and monolithic graphene ICs. The process is inverse to traditional Si technology. Passive elements are fabricated in the first metal layer and GFETs are formed with buried gate/source/drain in the second metal layer. Gate dielectric of 3.1 nm in equivalent oxide thickness (EOT) is employed. 500 nm-gate-length GFETs feature a yield of 80% and fT/fmax = 17 GHz/15.2 GHz RF performance. A high-performance monolithic graphene frequency multiplier is demonstrated using the proposed process. Functionality was demonstrated up to 8 GHz input and 16 GHz output. The frequency multiplier features a 3 dB bandwidth of 4 GHz and conversion gain of -26 dB.

  12. Fabricating an S&OP Process

    DEFF Research Database (Denmark)

    Lichen, Alex Yu

    Inspired by Latour’s (2005a) notion of matters of concern and M.C. Escher’s Circle Limit III as a representation of the Poincaré Disk, this study follows how an S&OP process was fabricated in a large Swedish manufacturing company. The study claims that when actors are fabricating the S&OP process......, local actors create emergent, ongoing and multiple matters of concern around it. The group demand chain, the actor who is responsible for guiding the implementation of the process, delegates the attempts to close these matters of concern to local actors located in separate times and spaces. As a result......, constituents of the S&OP process are dispersed in diverse local times and spaces rather than being coordinated in a single time and space by the group demand chain. Accounting is a set of matters of concern. The S&OP process and its purpose of integration come from an “absolute nothingness” – its minimal...

  13. Development of the Direct Fabrication Process for Plutonium Immobilization

    Energy Technology Data Exchange (ETDEWEB)

    Congdon, J.W.

    2001-07-10

    The current baseline process for fabricating pucks for the Plutonium Immobilization Program includes granulation of the milled feed prior to compaction. A direct fabrication process was demonstrated that eliminates the need for granulation.

  14. A scalable fabrication process of polymer microneedles

    Directory of Open Access Journals (Sweden)

    Yang S

    2012-03-01

    Full Text Available Sixing Yang, Yan Feng, Lijun Zhang, Nixiang Chen, Weien Yuan, Tuo JinSchool of Pharmacy, Shanghai Jiao Tong University, Shanghai, People's Republic of ChinaAbstract: While polymer microneedles may easily be fabricated by casting a solution in a mold, either centrifugation or vacuumizing is needed to pull the viscous polymer solution into the microholes of the mold. We report a novel process to fabricate polymer microneedles with a one-sided vacuum using a ceramic mold that is breathable but water impermeable. A polymer solution containing polyvinyl alcohol and polysaccharide was cast in a ceramic mold and then pulled into the microholes by a vacuum applied to the opposite side of the mold. After cross-linking and solidification through freeze-thawing, the microneedle patch was detached from the mold and transferred with a specially designed instrument for the drying process, during which the patch shrank evenly to form an array of regular and uniform needles without deformation. Moreover, the shrinkage of the patches helped to reduce the needles' size to ease microfabrication of the male mold. The dried microneedle patches were finally punched to the desired sizes to achieve various properties, including sufficient strength to penetrate skin, microneedles-absorbed water-swelling ratios, and drug-release kinetics. The results showed that the microneedles were strong enough to penetrate pigskin and that their performance was satisfactory in terms of swelling and drug release.Keywords: polymer microneedles, ceramic mold, polyvinyl alcohol, swelling

  15. Industrial stacks design; Diseno de chimeneas industriales

    Energy Technology Data Exchange (ETDEWEB)

    Cacheux, Luis [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1986-12-31

    The Instituto de Investigaciones Electricas (IIE) though its Civil Works Department, develops, under contract with CFE`s Gerencia de Proyectos Termoelectricos (Management of Fossil Power Plant Projects), a series of methods for the design of stacks, which pretends to solve the a present day problem: the stack design of the fossil power plants that will go into operation during the next coming years in the country. [Espanol] El Instituto de Investigaciones Electricas (IIE), a traves del Departamento de Ingenieria Civil, desarrolla, bajo contrato con la Gerencia de Proyectos Termoelectricos, de la Comision Federal de Electricidad (CFE), un conjunto de metodos para el diseno de chimeneas, con el que se pretende resolver un problema inmediato: el diseno de las chimeneas de las centrales termoelectricas que entraran en operacion durante los proximos anos, en el pais.

  16. Adaptive Control of Freeze-Form Extrusion Fabrication Processes (Preprint)

    National Research Council Canada - National Science Library

    Zhao, Xiyue; Landers, Robert G; Leu, Ming C

    2008-01-01

    Freeze-form Extrusion Fabrication (FEF) is an additive manufacturing process that extrudes high solids loading aqueous ceramic pastes in a layer-by-layer fashion below the paste freezing temperature for component fabrication...

  17. DWDM DFB LD fabricated by nanoimprint process

    Science.gov (United States)

    Liu, Wen; Wang, Lei; Zhou, Ning; Zhang, Yiwen; Qiu, Fei; Xu, Zhimou

    2011-02-01

    DFB LDs are key components in DWDM optical network. Now they are very expensive because the feedback grating period has to be controlled with very high accuracy and EBL is currently the most popular solution. We propose a high throughput, low cost NIL process based on a large stamp fabricated by SFIL and soft stamp pattern transfer method. DFB chips on 30mm*30mm area were manufactured with both good uniformity and performance. 13 ITU channels from 1540nm to 1560nm of 200GHz space are made. Our results show NIL has high potential to become another popular technology for DFB LD production, this cost effective and high efficiency manufacture solution may yield a significant impact to the future optical communication industry development.

  18. Optimum processing parameters for the fabrication of twill flax fabric-reinforced polypropylene (PP) composites

    Science.gov (United States)

    Zuhudi, Nurul Zuhairah Mahmud; Minhat, Mulia; Shamsuddin, Mohd Hafizi; Isa, Mohd Dali; Nur, Nurhayati Mohd

    2017-12-01

    In recent years, natural fabric thermoplastic composites such as flax have received much attention due to its attractive capabilities for structural applications. It is crucial to study the processing of flax fabric materials in order to achieve good quality and cost-effectiveness in fibre reinforced composites. Though flax fabric has been widely utilized for several years in composite applications due to its high strength and abundance in nature, much work has been concentrated on short flax fibre and very little work focused on using flax fabric. The effectiveness of the flax fabric is expected to give higher strength performance due to its structure but the processing needs to be optimised. Flax fabric composites were fabricated using compression moulding due to its simplicity, gives good surface finish and relatively low cost in terms of labour and production. Further, the impregnation of the polymer into the fabric is easier in this process. As the fabric weave structure contributes to the impregnation quality which leads to the overall performance, the processing parameters of consolidation i.e. pressure, time, and weight fraction of fabric were optimized using the Taguchi method. This optimization enhances the consolidation quality of the composite by improving the composite mechanical properties, three main tests were conducted i.e. tensile, flexural and impact test. It is observed that the processing parameter significantly affected the consolidation and quality of composite.

  19. A Rapid Process for Fabricating Gas Sensors

    Directory of Open Access Journals (Sweden)

    Chun-Ching Hsiao

    2014-07-01

    Full Text Available Zinc oxide (ZnO is a low-toxicity and environmentally-friendly material applied on devices, sensors or actuators for “green” usage. A porous ZnO film deposited by a rapid process of aerosol deposition (AD was employed as the gas-sensitive material in a CO gas sensor to reduce both manufacturing cost and time, and to further extend the AD application for a large-scale production. The relative resistance change (△R/R of the ZnO gas sensor was used for gas measurement. The fabricated ZnO gas sensors were measured with operating temperatures ranging from 110 °C to 180 °C, and CO concentrations ranging from 100 ppm to 1000 ppm. The sensitivity and the response time presented good performance at increasing operating temperatures and CO concentrations. AD was successfully for applied for making ZnO gas sensors with great potential for achieving high deposition rates at low deposition temperatures, large-scale production and low cost.

  20. Decorative design of ceramic tiles adapted to inkjet printing employing digital image processing; Diseno decorativo de pavimentos ceramicos adaptado a inyeccion de tinta mediante tratamiento digital de imagen

    Energy Technology Data Exchange (ETDEWEB)

    Defez, B.; Santiago-Praderas, V.; Lluna, E.; Peris-Fajarnes, G.; Dunai, E.

    2013-09-01

    The ceramic tile sector is a very competitive industry. The designer's proficiency to offer new models of the decorated surface, adapted to the production means, plays a very important role in the competitiveness. In the present work, we analyze the evolution of the design process in the ceramic sector, as much as the changes experimented in parallel by the printing equipment. Afterwards, we present a new concept of ceramic design, based on digital image processing. This technique allows the generation of homogeneous and non-repetitive designs for large surfaces, especially thought for inkjet printing. With the programmed algorithms we have compiled a prototype software for the assistance of the ceramic design. This tool allows creating continuous designs for large surfaces saving developing time. (Author)

  1. FINAL PROCESS DEPENDENT DIMENSIONAL CHANGES OF DOUBLE KNIT FABRICS

    Directory of Open Access Journals (Sweden)

    Vedat ÖZYAZGAN

    2012-01-01

    Full Text Available In this paper Ne 30/1 cotton yarn obtained by using pure cotton fibers is employed. 1x1, 2x1 and 3x1 Rib fabrics were knitted with yarns at different gauges. During the knitting process, the tension was kept constant. In order to investigate the relaxation on the knitting process fabric samples were treated using three relaxation processes; dry, wet and full respectively. After each relaxation process, stitches dimensions were measured. As a result of these measurements, it is observed that as the relaxation increases the stitches length decreases while the stitches width increases. In rib knitting, As the fabric stretches increases the stitch length increases. As a result it is observed that as the stitch length increases, the width of the stitches increases linearly. In all rib fabrics, increase in the stitch density leads to an increase in the weight of the fabric.

  2. An improved fabrication process for Si-detector-compatible JFETs

    International Nuclear Information System (INIS)

    Piemonte, Claudio; Dalla Betta, Gian-Franco; Boscardin, Maurizio; Gregori, Paolo; Zorzi, Nicola; Ratti, Lodovico

    2006-01-01

    We report on JFET devices fabricated on high-resistivity silicon with a radiation detector technology. The problems affecting previous versions of these devices have been thoroughly investigated and solved by developing an improved fabrication process, which allows for a sizeable enhancement in the JFET performance. In this paper, the main features of the fabrication technology are presented and selected results from the electrical and noise characterization of transistors are discussed

  3. Streamlining CubeSat Solar Panel Fabrication Processes

    OpenAIRE

    Sandberg, Ariel; Smith, Timothy

    2016-01-01

    A critical facet of CubeSat fabrication is solar panel characterization and assembly. Though capable of producing flight quality solar subsystems, traditional methods of solar panel fabrication contain intrinsic inefficiencies and inconsistencies that compromise the subsystem’s overall reliability. Taking Michigan Exploration Laboratory’s (MXL) heritage solar panel procedures as a case study, this investigation sought to streamline the solar panel fabrication process to increase its yield, co...

  4. Design and fabrication of a mechanical alloying system for preparing intermetallic, nanocrystalline, amorphous and quasicrystalline compounds; Diseno y fabricacion de un sistema de aleado mecanico para preparar compuestos intermetalicos, nanocristalinos, amorfos y cuasicristalinos

    Energy Technology Data Exchange (ETDEWEB)

    Bonifacio M, J.; Iturbe G, J.L.; Castaneda J, G. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    2002-07-01

    In this work a grinding system was designed and fabricated which allowed to improve the operation conditions in time, frequency, temperature and selection of the grinding media and that allow the contamination decrease of the compounds. By means of this method of mechanical alloying new metallic compounds can be produced, starting from elemental powders, with fine and controlled microstructures. These compounds prepared by this method are going to be used as materials for the hydrogen storage. (Author)

  5. Process development and fabrication for sphere-pac fuel rods

    International Nuclear Information System (INIS)

    Welty, R.K.; Campbell, M.H.

    1981-06-01

    Uranium fuel rods containing sphere-pac fuel have been fabricated for in-reactor tests and demonstrations. A process for the development, qualification, and fabrication of acceptable sphere-pac fuel rods is described. Special equipment to control fuel contamination with moisture or air and the equipment layout needed for rod fabrication is described and tests for assuring the uniformity of the fuel column are discussed. Fuel retainers required for sphere-pac fuel column stability and instrumentation to measure fuel column smear density are described. Results of sphere-pac fuel rod fabrication campaigns are reviewed and recommended improvements for high throughput production are noted

  6. Fabrication process for a gradient index x-ray lens

    Science.gov (United States)

    Bionta, Richard M.; Makowiecki, Daniel M.; Skulina, Kenneth M.

    1995-01-01

    A process for fabricating high efficiency x-ray lenses that operate in the 0.5-4.0 keV region suitable for use in biological imaging, surface science, and x-ray lithography of integrated circuits. The gradient index x-ray optics fabrication process broadly involves co-sputtering multi-layers of film on a wire, followed by slicing and mounting on block, and then ion beam thinning to a thickness determined by periodic testing for efficiency. The process enables the fabrication of transmissive gradient index x-ray optics for the 0.5-4.0 keV energy range. This process allows the fabrication of optical elements for the next generation of imaging and x-ray lithography instruments m the soft x-ray region.

  7. U-10Mo Baseline Fuel Fabrication Process Description

    Energy Technology Data Exchange (ETDEWEB)

    Hubbard, Lance R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Arendt, Christina L. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Dye, Daniel F. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Clayton, Christopher K. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Lerchen, Megan E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Lombardo, Nicholas J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Lavender, Curt A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Zacher, Alan H. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2017-09-27

    This document provides a description of the U.S. High Power Research Reactor (USHPRR) low-enriched uranium (LEU) fuel fabrication process. This document is intended to be used in conjunction with the baseline process flow diagram (PFD) presented in Appendix A. The baseline PFD is used to document the fabrication process, communicate gaps in technology or manufacturing capabilities, convey alternatives under consideration, and as the basis for a dynamic simulation model of the fabrication process. The simulation model allows for the assessment of production rates, costs, and manufacturing requirements (manpower, fabrication space, numbers and types of equipment, etc.) throughout the lifecycle of the USHPRR program. This document, along with the accompanying PFD, is updated regularly

  8. Improvement on fabrication process of CANDU type reactor fuels

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Chang Bum; Chung, Sang Tae; Kim, Hyung Soo; Park, Choon Ho

    1993-05-01

    The study on fabrication of the nuclear fuel for heavy water cooled reactor is performed. Among the fabrication processes of nuclear fuel, welding thickness between fuel rod and end cap can occur a serious error in total fuel length. Therefore, for nuclear fuel design, the thickness of end cap and changed weight of zircaloy-4 tube must be measured accurately. For welding performance, microstructure of welding point is investigated successfully. The result of the study shows the possibility of cost reduction and quality improvement by simplification of fabrication process of nuclear fuel. (Author).

  9. Brazing process in nuclear fuel element fabrication

    International Nuclear Information System (INIS)

    Katam, K.; Sudarsono

    1982-01-01

    The purpose of the brazing process is to join the spacers and pads of fuel pins, so that the process is meant as a soldering technique and not only as a hardening or reinforcing process such as in common brazing purposes. There are some preliminary processes before executing the brazing process such as: materials preparation, sand blasting, brazing metal coating tack welding the spacers and pads on the fuel cladding. The metal brazing used is beryllium in strip form which will be evaporated in vacuum condition to coat the spacers and pads. The beryllium vapor and dust is very hazardous to the workers, so all the line process of brazing needs specials safety protection and equipment to protect the workers and the processing area. Coating process temperature is 2470 deg C with a vacuum pressure of 10 -5 mmHg. Brazing process temperature process is 1060 deg C with a vacuum pressure of 10 -6 mmHg. The brazing process with beryllium coating probably will give metallurgical structural change in the fuel cladding metal at the locations of spacers and pads. The quality of brazing is highly influenced by and is depending on the chemical composition of the metal and the brazing metal, materials preparations, temperature, vacuum pressure, time of coating and brazing process. The quality control of brazing could be performed with methods of visuality geometry, radiography and metallography. (author)

  10. Fabrication of Separator Demonstration Facility process vessel

    International Nuclear Information System (INIS)

    Oberst, E.F.

    1985-01-01

    The process vessel system is the central element in the Separator Development Facility (SDF). It houses the two major process components, i.e., the laser-beam folding optics and the separators pods. This major subsystem is the critical-path procurement for the SDF project. Details of the vaious parts of the process vessel are given

  11. Research on plant of metal fuel fabrication using casting process

    International Nuclear Information System (INIS)

    Senda, Yasuhide; Mori, Yukihide

    2003-12-01

    This document presents the plant concept of metal fuel fabrication system (38tHM/y) using casting process in electrolytic recycle, which based on recent studies of its equipment design and quality control system. And we estimate the cost of its construction and operation, including costs of maintenance, consumed hardware and management of waste. The content of this work is as follows. (1) Designing of fuel fabrication equipment: We make material flow diagrams of the fuel fabrication plant and rough designs of the injection casting furnace, demolder and inspection equipment. (2) Designing of resolution system of liquid waste, which comes from analytical process facility. Increased analytical items, we rearrange analytical process facility, estimate its chemicals and amount of waste. (3) Arrangement of equipments: We made a arrangement diagram of the metal fuel fabrication equipments in cells. (4) Estimation of cost data: We estimated cost to construct the facility and to operate it. (author)

  12. Process for fabricating continuous lengths of superconductor

    Science.gov (United States)

    Kroeger, Donald M.; List, III, Frederick A.

    1998-01-01

    A process for manufacturing a superconductor. The process is accomplished by depositing a superconductor precursor powder on a continuous length of a first substrate ribbon, overlaying a continuous length of a second substrate ribbon on said first substrate ribbon, and applying sufficient pressure to form a bound layered superconductor precursor between said first substrate ribbon and said second substrates ribbon. The layered superconductor precursor is then heat treated to form a super conductor layer.

  13. Molecular sieving silica membrane fabrication process

    Science.gov (United States)

    Raman, Narayan K.; Brinker, Charles Jeffrey

    1999-01-01

    A process for producing a molecular sieve silica membrane comprising depositing a hybrid organic-inorganic polymer comprising at least one organic constituent and at least one inorganic constituent on a porous substrate material and removing at least a portion of the at least one organic constituent of the hybrid organic-inorganic polymer, forming a porous film.

  14. Superconducting materials fabrication process and materials obtained

    International Nuclear Information System (INIS)

    Lafon, M.O.; Magnier, C.

    1989-01-01

    The preparation process of a fine powder of YBaCuO type superconductors of easy sintering comprises: mixing in presence of alcohol an aqueous solution of rare earth nitrate or acetate, alkaline earth nitrate or acetate and copper nitrate or acetate and an oxalic acid solution, the pH value of the mixture is comprised between 2 and 4, the obtained precipitate is separated, dried, calcined and eventually crushed [fr

  15. Design and fabrication of a chamber for the deposit of thin films by laser ablation; Diseno y fabricacion de una camara para el deposito de peliculas delgadas por ablacion laser

    Energy Technology Data Exchange (ETDEWEB)

    Chirino O, S.; Escobar A, I.; Camps C, E.; Garcia E, J.I. [Departamento de Fisica, ININ, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    2000-07-01

    The laser ablation technique is an alternative for the obtention of thin films which is less expensive, more reliable, efficient and with some advantages with respect to conventional processes. On of the most important components which forms a laser ablation system is the vacuum chamber, that has as general purposes the following: a) To carry out studies about plasma such as optical emission spectroscopy and measurements by deflectometry. b) To carry out an In situ monitoring about the film growth through the reflectivity measurements of the combination substrate-film. c) To deposit thin films of different materials such as oxides, carbon, metals, etc. In this work it is showed how the vacuum chamber was designed and made to perform the store of thin films by laser ablation and for characterising the formed plasma as a result of the ablation process. The chamber design was enough versatile that will allow to add it more accessory just making it simple modifications. Its cost was very cheap more or less one twentieth of a commercial chamber. (Author)

  16. Advanced Fabrication Processes for Superconducting Very Large Scale Integrated Circuits

    Science.gov (United States)

    2015-10-13

    Josephson junctions,” J. Appl. Phys., vol. 104, no. 2, July 2008, Art. ID 023909. [9] S.K. Tolpygo and D. Amparo , “Fabrication-process-induced...J. Appl. Phys., vol. 107, No. 7, 073906, Apr. 2010. [11] S.K. Tolpygo, D. Amparo , R.T. Hunt, J.A. Vivalda, and D.T. Yohannes, “Diffusion stop...June 2011. [12] D. Amparo and S.K. Tolpygo, “Investigation of the role of H in fabrication-process-induced variations of Nb/Al/AlOx/Nb Josephson

  17. Property-process relationships in nuclear fuel fabrication

    International Nuclear Information System (INIS)

    Tikare, V.

    2015-01-01

    Nuclear fuels are fabricated using many different techniques as they come in a large variety of shapes and compositions. The design and composition of nuclear fuels are predominantly dictated by the engineering requirements necessary for their function in reactors of various designs. Other engineering properties requirements originate from safety and security concerns, and the easy of handling, storing, transporting and disposing of the radioactive materials. In this chapter, the more common of these fuels will be briefly reviewed and the methods used to fabricate them will be presented. The fuels considered in this paper are oxide fuels used in LWRs and FRs, metal fuels in FRs and particulate fuels used in HTGRs. Fabrication of alternative fuel forms and use of standard fuels in alternative reactors will be discussed briefly. The primary motivation to advance fuel fabrication is to improve performance, reduce cost, reduce waste or enhance safety and security of the fuels. To achieve optimal performance, developing models to advance fuel fabrication has to be done in concert with developing fuel performance models. The specific properties and microstructures necessary for improved fuel performance must be identified using fuel performance models, while fuel fabrication models that can determine processing variables to give the desired microstructure and materials properties must be developed. (author)

  18. Current status of vibro-packed fuel fabrication process development

    International Nuclear Information System (INIS)

    Kihara, Yoshiyuki

    2004-01-01

    In the feasibility study of FBR cycle system, the concept of future commercialized fuel is 'low-decontaminated MA(minor actinide) fuel', which contains high radioactive rare earth elements and MAs. This fuel will optimize a positive feature of the fast reactor, which allows high impurities for the fuel. Therefore, this fuel should be fabricated not in a conventional glove-box but in a cell with remote handling. A vibro-packed fuel, like sphere-pac fuel or vipac fuel, is well-suited, and the development of fabrication procedure is in progress as a candidate for the commercialized fuel fabrication process. Results of the three topics are reported: 1) results of uranium dioxide particle fabrication with external gelation process containing samarium (Sm) as a representative element of rare earth impurities. 2) results of vibro-packing experiments using several simulated materials for the prediction of filling behavior during sphere-pac fuel fabrication and 3) results of evaluation on filling behavior of vipac fuel particles with getter (uranium metal) particles. (author)

  19. Process for fabrication of molybdenum-base wrought products

    International Nuclear Information System (INIS)

    1977-01-01

    A process for the fabrication of molybdenum-base wrought products is described comprising the steps of providing a molybdenum material containing at least 50% molybdenum in a substantially fully annealed condition, warming the said material to a temperature in the range of from 500 0 F to 1200 0 F, and deforming the warmed said material into a wrought product. (author)

  20. Progressive defects caused by crosstalk between mask fabrication processes

    Science.gov (United States)

    Oh, Jongkeun; Choi, Junyeol; Choi, Jaehyuck; Lee, Han-shin; Koh, Hyungho; Kim, Byunggook; Jeon, Chanuk

    2013-06-01

    Most of defects generated in mask fabrication processes have been mainly created during each unit process. It becomes more important to detect and remove smaller defects on mask as pattern nodes keep shrinking. Each unit processes are getting not only more challenging to sustain mask quality and defect level but also more influencing on other processes for smaller pattern nodes. New type of defects based on such influences (crosstalk) between different processes is starting to emerge, which is requesting for a revision of defect reduction strategy because dealing with crosstalk defects is directly related with quality and TAT of mask manufacturing. It is relatively difficult to properly understand root-cause or working mechanism of defects generated by crosstalk between different processes. This is because interaction between different processes from defect generation perspectives has hardly been studied. In this paper, we introduce emerging progressive defects created while etched masks are undergoing cleaning process or subsequent events of moving to next process or temporary storage. We will investigate how etch gas residues on mask surface remaining after etching process interact with cleaning chemicals or moisture from subsequent process or environment to trigger defect generation and its growth. We will also examine effects of POD outgassing on generation of crosstalk progressive defect. Based on this understanding, appropriate solutions to mitigate defects caused by crosstalk between mask fabrication processes will be proposed. It is believed that new type of progressive defects caused by crosstalk between different mask fabrication processes will be more flourishing in the near future where mask blank materials, mask manufacturing processes, and chemicals need to diversify in order to meet much tighter specifications of mask quality. Therefore, it is very crucial to have right understandings on the interactions between various processes and eradicate

  1. Bioclimatic analysis and its impact within the design methodology; Analisis bioclimatico y su impacto dentro de la metodologia de diseno

    Energy Technology Data Exchange (ETDEWEB)

    Fuentes Fleixanet, Victor A; Rodriguez Viqueira Manuel [Universidad Autonoma Metropolitana Azcapotzalco, Mexico, D.F(Mexico)

    2000-07-01

    This paper is a proposal for the systematization of the process of bioclimatic design, particularly in its analytical stage. It is based on the proposals of the classic researchers such as: Olgyay, Givoni and Szokolay, but also in new contributions like those of Yeang. Nevertheless, it is about a methodology adapted to the specific requirements of teaching and research that are carried out in the Bioclimatic Design Laboratory of the Universidad Autonoma Metropolitana, Azcapotzalco Unit. What is presented here is a part of a very ample research project that intends to develop or to structure a design methodology that incorporates the environmental variables related to man and architecture: of course, with the objective of facilitating the designer work so that the final architectonic product has a more harmonic response to the environment, offers conditions of integral well- being to its occupants and be is efficient in the handling of the resources. It also looks for the definition of the necessary analysis, design and evaluation tools, necessary in order that the application of the methodology is clear, simple and can be carried out by any designer, even if he does not have a wide knowledge of bioclimatic design. [Spanish] Este trabajo es una propuesta para la sistematizacion del proceso de diseno bioclimatico, particularmente en su etapa analitica. Se basa en las propuestas de los investigadores clasicos como: Olgyay, Givoni y Szokolay, pero tambien en nuevas aportaciones como las de Yeang. Sin embargo se trata de una metodologia adaptada a los requerimientos especificos de docencia e investigacion que se llevan a cabo en el Laboratorio de Diseno Bioclimatico de la Universidad Autonoma Metropolitana Unidad Azcapotzalco. Lo que aqui se presenta forma parte de un proyecto de investigacion muy amplio que pretende, desarrollar o estructurar una metodologia de diseno que incorpore las variables ambientales relacionadas con el hombre y la arquitectura: desde luego, con

  2. USHPRR FUEL FABRICATION PILLAR: FABRICATION STATUS, PROCESS OPTIMIZATIONS, AND FUTURE PLANS

    Energy Technology Data Exchange (ETDEWEB)

    Wight, Jared M.; Joshi, Vineet V.; Lavender, Curt A.

    2018-03-12

    The Fuel Fabrication (FF) Pillar, a project within the U.S. High Performance Research Reactor Conversion program of the National Nuclear Security Administration’s Office of Material Management and Minimization, is tasked with the scale-up and commercialization of high-density monolithic U-Mo fuel for the conversion of appropriate research reactors to use of low-enriched fuel. The FF Pillar has made significant steps to demonstrate and optimize the baseline co-rolling process using commercial-scale equipment at both the Y-12 National Security Complex (Y-12) and BWX Technologies (BWXT). These demonstrations include the fabrication of the next irradiation experiment, Mini-Plate 1 (MP-1), and casting optimizations at Y-12. The FF Pillar uses a detailed process flow diagram to identify potential gaps in processing knowledge or demonstration, which helps direct the strategic research agenda of the FF Pillar. This paper describes the significant progress made toward understanding the fuel characteristics, and models developed to make informed decisions, increase process yield, and decrease lifecycle waste and costs.

  3. Infra-red process for colour fixation on fabrics

    International Nuclear Information System (INIS)

    Raymond, D.J.; Biau, D.

    1983-01-01

    Infra-red radiations find wide application in industrial processes as heating, drying, stoving and forming. The results are often far better than those from the other techniques: convection oven, gas IR etc ... They come from the electric IR specific advantages: energy direct transmission, emitter and product spectral coupling, possible selectivity. That is the case in the Textile Industry, where experiments showed that infra-red process heating could be efficient for colour fixation on fabrics. Shorter production cycles and energy saving are the main results

  4. Process for the fabrication of nuclear fuel oxide pellets

    International Nuclear Information System (INIS)

    Francois, Bernard; Paradis, Yves.

    1977-01-01

    Process for the fabrication of nuclear fuel oxide pellets of the type for which particles charged with an organic binder -selected from the group that includes polyvinyl alcohol, carboxymethyl cellulose, polyvinyl compounds and methyl cellulose- are prepared from a powder of such an oxide, for instance uranium dioxide. These particles are then compressed into pellets which are then sintered. Under this process the binder charged particles are prepared by stirring the powder with a gas, spraying on to the stirred powder a solution or a suspension in a liquid of this organic binder in order to obtain these particles and then drying the particles so obtained with this gas [fr

  5. One-step electrodeposition process to fabricate cathodic superhydrophobic surface

    Energy Technology Data Exchange (ETDEWEB)

    Chen Zhi, E-mail: c2002z@nwpu.edu.cn [Department of Applied Physics, Northwestern Polytechnical University, Xi' an 710129 (China); Li Feng [Department of Applied Physics, Northwestern Polytechnical University, Xi' an 710129 (China); Hao Limei [Department of Applied Physics, Xi' an University of Science and Technology, Xi' an 710054 (China); Chen Anqi; Kong Youchao [Department of Applied Physics, Northwestern Polytechnical University, Xi' an 710129 (China)

    2011-12-01

    In this work, a rapid one-step process is developed to fabricate superhydrophobic cathodic surface by electrodepositing copper plate in an electrolyte solution containing manganese chloride (MnCl{sub 2}{center_dot}4H{sub 2}O), myristic acid (CH{sub 3}(CH{sub 2}){sub 12}COOH) and ethanol. The superhydrophobic surfaces were characterized by means of scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). The shortest electrolysis time for fabricating a superhydrophobic surface is about 1 min, the measured maximum contact angle is 163 Degree-Sign and rolling angle is less than 3 Degree-Sign . Furthermore, this method can be easily extended to other conductive materials. The approach is time-saving and cheap, and it is supposed to have a promising future in industrial fields.

  6. A solar module fabrication process for HALE solar electric UAVs

    Energy Technology Data Exchange (ETDEWEB)

    Carey, P.G.; Aceves, R.C.; Colella, N.J.; Williams, K.A. [Lawrence Livermore National Lab., CA (United States); Sinton, R.A. [Private Consultant, San Jose, CA (United States); Glenn, G.S. [Spectrolab, Inc., Sylmar, CA (United States)

    1994-12-12

    We describe a fabrication process used to manufacture high power-to-weight-ratio flexible solar array modules for use on high-altitude-long-endurance (HALE) solar-electric unmanned air vehicles (UAVs). These modules have achieved power-to-weight ratios of 315 and 396 W/kg for 150{mu}m-thick monofacial and 110{mu}m-thick bifacial silicon solar cells, respectively. These calculations reflect average module efficiencies of 15.3% (150{mu}m) and 14.7% (110{mu}m) obtained from electrical tests performed by Spectrolab, Inc. under AMO global conditions at 25{degrees}C, and include weight contributions from all module components (solar cells, lamination material, bypass diodes, interconnect wires, and adhesive tape used to attach the modules to the wing). The fabrication, testing, and performance of 32 m{sup 2} of these modules will be described.

  7. A new planetary structure fabrication process using phosphoric acid

    Science.gov (United States)

    Buchner, Christoph; Pawelke, Roland H.; Schlauf, Thomas; Reissner, Alexander; Makaya, Advenit

    2018-02-01

    Minimising the launch mass is an important aspect of exploration mission planning. In-situ resource utilisation (ISRU) can improve this by reducing the amount of terrestrial materials needed for planetary exploration activities. We report on a recently concluded investigation into the requirements and available technologies for creating hardware on extra-terrestrial bodies, using the limited resources available on site. A trade-off of ISRU technologies for hardware manufacturing was conducted. A new additive manufacturing process suitable for fabricating structures on the Moon or Mars was developed. The process uses planetary regolith as the base material and concentrated phosphoric acid as the liquid binder. Mixing the reagents creates a sticky construction paste that slowly solidifies into a hard, rock-like material. Prior to solidification, the paste is extruded in layers, creating the desired structures in a 3D printing process. We used Martian regolith simulant JSC-Mars-1A, but the process is not selective towards regolith composition. Samples were exposed to thermal cycles and were mechanically characterised. Reduced-scale demonstrator structures were printed to demonstrate structure fabrication using the developed process.

  8. Optical microdevices fabricated using femtosecond laser processing (Conference Presentation)

    Science.gov (United States)

    Otuka, Adriano J. G.; Tomázio, Nathália B.; Tribuzi, Vinicius; Ferreira, Paulo Henrique D.; De Boni, Leonardo; Mendonça, Cleber R.

    2017-02-01

    Femtosecond laser processing techniques have been widely employed to produce micro or nanodevices with special features. These devices can be selectively doped with organic dyes, biological agents, nanoparticles or carbon nanotubes, increasing the range of applications. Acrylate polymers can be easily doped with various compounds, and therefore, they are interesting materials for laser fabrication techniques. In this work, we use multiphoton absorption polymerization (MAP) and laser ablation to fabricate polymeric microdevices for optical applications. The polymeric sample used in this work is composed in equal proportions of two three-acrylate monomers; while tris(2-hydroxyethyl)isocyanurate triacrylate gives hardness to the structure, the ethoxylated(6) trimethyl-lolpropane triacrylate reduces the shrinkage tensions upon polymerization. These monomers are mixed with a photoinitiator, the 2,4,6-trimetilbenzoiletoxifenil phosphine oxide, enabling the sample polymerization after laser irradiation. Using MAP, we fabricate three-dimensional structures doped with fluorescent dyes. These structures can be used in several optical applications, such as, RGB fluorescent microdevices or microresonators. Using azo compounds like dopant in the host resin, we can apply these structures in optical data storage devices. Using laser ablation technique, we can fabricate periodic microstructures inside polymeric bulks doped with xanthene dyes and single-walled carbon nanotubes, aiming applications in random laser experiments. In structured bulks we observed multi-narrow emission peaks over the xanthene fluorescence emission. Furthermore, in comparison with non-structured bulks, we observed that the periodic structure decreased the degree of randomness, reducing the number of peaks, but defining their position.

  9. Fabrication process for the PEP II RF cavities

    Energy Technology Data Exchange (ETDEWEB)

    Franks, R.M.; Rimmer, R.A. [Lawrence Berkeley National Lab., CA (United States); Schwarz, H. [Stanford Linear Accelerator Center, Menlo Park, CA (United States)

    1997-06-05

    This paper presents the major steps used in the fabrication of the 26 RF Cavities required for the PEP-II B-factory. Several unique applications of conventional processes have been developed and successfully implemented: electron beam welding (EBW), with minimal porosity, of .75 inch (19 mm) copper cross-sections; extensive 5-axis milling of water channels; electroplating of .37 inch (10 mm) thick OFE copper; tuning of the cavity by profiling beam noses prior to final joining with the cavity body; and machining of the cavity interior, are described here.

  10. Information management data base for fusion target fabrication processes

    International Nuclear Information System (INIS)

    Reynolds, J.

    1983-01-01

    A computer-based data management system has been developed to handle data associated with target fabrication processes including glass microballoon characterization, gas filling, materials coating, and storage locations. The system provides automatic data storage and computation, flexible data entry procedures, fast access, automated report generation, and secure data transfer. It resides on a CDC CYBER 175 computer and is compatible with the CDC data base language Query Update, but is based on custom fortran software interacting directly with the CYBER's file management system. The described data base maintains detailed, accurate, and readily available records of fusion targets information

  11. Electrochemical/Pyrometallurgical Waste Stream Processing and Waste Form Fabrication

    Energy Technology Data Exchange (ETDEWEB)

    Steven Frank; Hwan Seo Park; Yung Zun Cho; William Ebert; Brian Riley

    2015-07-01

    This report summarizes treatment and waste form options being evaluated for waste streams resulting from the electrochemical/pyrometallurgical (pyro ) processing of used oxide nuclear fuel. The technologies that are described are South Korean (Republic of Korea – ROK) and United States of America (US) ‘centric’ in the approach to treating pyroprocessing wastes and are based on the decade long collaborations between US and ROK researchers. Some of the general and advanced technologies described in this report will be demonstrated during the Integrated Recycle Test (IRT) to be conducted as a part of the Joint Fuel Cycle Study (JFCS) collaboration between US Department of Energy (DOE) and ROK national laboratories. The JFCS means to specifically address and evaluated the technological, economic, and safe guard issues associated with the treatment of used nuclear fuel by pyroprocessing. The IRT will involve the processing of commercial, used oxide fuel to recover uranium and transuranics. The recovered transuranics will then be fabricated into metallic fuel and irradiated to transmutate, or burn the transuranic elements to shorter lived radionuclides. In addition, the various process streams will be evaluated and tested for fission product removal, electrolytic salt recycle, minimization of actinide loss to waste streams and waste form fabrication and characterization. This report specifically addresses the production and testing of those waste forms to demonstrate their compatibility with treatment options and suitability for disposal.

  12. Silicon Solar Cell Process Development, Fabrication and Analysis, Phase 1

    Science.gov (United States)

    Yoo, H. I.; Iles, P. A.; Tanner, D. P.

    1979-01-01

    Solar cells from RTR ribbons, EFG (RF and RH) ribbons, dendritic webs, Silso wafers, cast silicon by HEM, silicon on ceramic, and continuous Czochralski ingots were fabricated using a standard process typical of those used currently in the silicon solar cell industry. Back surface field (BSF) processing and other process modifications were included to give preliminary indications of possible improved performance. The parameters measured included open circuit voltage, short circuit current, curve fill factor, and conversion efficiency (all taken under AM0 illumination). Also measured for typical cells were spectral response, dark I-V characteristics, minority carrier diffusion length, and photoresponse by fine light spot scanning. the results were compared to the properties of cells made from conventional single crystalline Czochralski silicon with an emphasis on statistical evaluation. Limited efforts were made to identify growth defects which will influence solar cell performance.

  13. System for the design of electrical distribution substations; Sistema para el diseno de subestaciones electricas de distribucion

    Energy Technology Data Exchange (ETDEWEB)

    Zayas Perez, Benjamin Eddie; Islas Perez, Eduardo; Bahena Rada, Jessica Liliana; Romero Lima, Jesus [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico); Sierra Rodriguez, Benjamin; Moreno Diaz, Humberto [Comision Federal de Electricidad (Mexico)

    2011-07-01

    The physical design of electric substations involves a variety of activities, such as developing, reviewing and performing modifications to different design proposals, estimating costs and producing documents to be integrated into an executive project. These activities are usually conducted at the Distribution Divisions of the Federal Electric Commission (CFE) through two separate processes: the development of engineering plans with computer-aided design software (CAD) and volumetric calculations for the initial budget using conventional spreadsheets. The documents are manually developed on an individual basis, without the existence of any functions to allow for automatically updating the design modifications of any of the plans. The corresponding initial budget becomes a lengthy and laborious process with the likelihood of inconsistencies among the documents. In order to optimize the design process for the public and electromechanical works of electric substations (ES) in a three-dimensional (3D) graphic environment, the IIE's Management of Process Supervision, in coordination with the CFE Distribution Subdivision, developed the System for the Design of Electric Substation Distribution (SDESD). This system makes use of the advantages of CAD3D technology to develop detail engineering, cost engineering to calculate initial budgets and virtual reality for three-dimensional interactive navigation. It is worth mentioning that this system is currently in the implementation phase at the CFE Distribution Subdivision. This article briefly describes the main stages in the development of the project, as well as the functioning and principal components of the system. [Spanish] El diseno fisico de subestaciones electricas implica una variedad de actividades, tales como elaborar, revisar y efectuar modificaciones de diferentes propuestas de diseno, estimar costos y producir documentos, para integrarlos como parte de un proyecto ejecutivo. Estas actividades usualmente se

  14. Green, scalable, binderless fabrication of a single-walled carbon nanotube nonwoven fabric based on an ancient Japanese paper process.

    Science.gov (United States)

    Kobashi, Kazufumi; Hirabayashi, Tatsuya; Ata, Seisuke; Yamada, Takeo; Futaba, Don N; Hata, Kenji

    2013-12-11

    We propose a fabrication method for carbon nanotube (CNT) nonwoven fabrics based on an ancient Japanese papermaking process where paper is made from natural plant fibers. In our method, CNT nonwoven fabrics are made by a scalable process of filtering binder-free, aqueous suspensions of CNTs. The aqueous suspension of these entangled single-walled carbon nanotube (SWNT) aggregates enabled smooth filtration through a cellulose filter with large pores (8 μm). The "wet SWNT cakes," which were composed solely of SWNT and water and obtained after filtration, were press-dried to fabricate an SWNT nonwoven fabric. This environmentally friendly process employs water and the raw CNT material alone. Moreover, the scalability of this process was demonstrated by manufacturing a large area (A3, 30 × 42 cm; thickness: 40-150 μm), self-supporting SWNT nonwoven fabric with a density of 0.4 g/cm(3), a basis weight of 0.2 g/m(2) , a porosity of 63%, and a specific surface area of 740 m(2)/g. This SWNT nonwoven fabric is anticipated to find application as functional particle-supported sheets, electrode materials, and filters.

  15. A microelectromechanical accelerometer fabricated using printed circuit processing techniques

    International Nuclear Information System (INIS)

    Rogers, J E; Ramadoss, R; Ozmun, P M; Dean, R N

    2008-01-01

    A microelectromechanical systems (MEMS) capacitive-type accelerometer fabricated using printed circuit processing techniques is presented. A Kapton polymide film is used as the structural layer for fabricating the MEMS accelerometer. The accelerometer proof mass along with four suspension beams is defined in the Kapton polyimide film. The proof mass is suspended above a Teflon substrate using a spacer. The deflection of the proof mass is detected using a pair of capacitive sensing electrodes. The top electrode of the accelerometer is defined on the top surface of the Kapton film. The bottom electrode is defined in the metallization on the Teflon substrate. The initial gap height is determined by the distance between the bottom electrode and the Kapton film. For an applied external acceleration (normal to the proof mass), the proof mass deflects toward or away from the fixed bottom electrode due to inertial force. This deflection causes either a decrease or increase in the air-gap height thereby either increasing or decreasing the capacitance between the top and the bottom electrodes. An example PCB MEMS accelerometer with a square proof mass of membrane area 6.4 mm × 6.4 mm is reported. The measured resonant frequency is 375 Hz and the Q-factor in air is 0.52

  16. Quality control of CANDU6 fuel element in fabrication process

    International Nuclear Information System (INIS)

    Li Yinxie; Zhang Jie

    2012-01-01

    To enhance the fine control over all aspects of the production process, improve product quality, fuel element fabrication process for CANDU6 quality process control activities carried out by professional technical and management technology combined mode, the quality of the fuel elements formed around CANDU6 weak links - - end plug , and brazing processes and procedures associated with this aspect of strict control, in improving staff quality consciousness, strengthening equipment maintenance, improved tooling, fixtures, optimization process test, strengthen supervision, fine inspection operations, timely delivery carry out aspects of the quality of information and concerns the production environment, etc., to find the problem from the improvement of product quality and factors affecting the source, and resolved to form the active control, comprehensive and systematic analysis of the problem of the quality management concepts, effectively reducing the end plug weld microstructure after the failure times and number of defects zirconium alloys brazed, improved product quality, and created economic benefits expressly provided, while staff quality consciousness and attention to detail, collaboration department, communication has been greatly improved and achieved very good management effectiveness. (authors)

  17. Design and construction of a new furnace combustion pilot in IIE; Diseno y construccion de un nuevo horno experimental de combustion en el IIE

    Energy Technology Data Exchange (ETDEWEB)

    Martinez Flores, Marco Antonio; Tamayo Flores, G. A. [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)]. E-mail: mamf@iie.org.mx; gatamayo@iie.org.mx

    2010-11-15

    To expand the scope of studies and technological developments in the Laboratory of Combustion of the Thermal Process Management a new experimental furnace with a capacity of 1.5 MWt was designed and built. Spray design studies with real operational evaluation (comparison of emission of Combustion products and thermal behavior) as well as information on the behavior of the NO{sub x} emissions will be produced. An automatic control system using a water cooling jacket provides the cooling of the furnace. The furnace design is modular, consisting of six sections. Currently three trials to its maximum load of operation have been performed. The results show that the global energy balance of the furnace matches the design. The flue gas residence time and temperature also match those at the exit of steam generators of big capacity. [Spanish] Para ampliar las posibilidades de estudios y desarrollos tecnologicos del laboratorio de combustion de la Gerencia de Procesos Termicos, se diseno y construyo un nuevo horno experimental con capacidad maxima de 1.5 MegaWatts termicos (MWt). Este horno permitira realizar estudios de diseno de atomizadores con evaluacion de operacion real (comparacion de emision de productos de combustion y comportamiento termico), asi como ampliar la informacion que se tiene en el comportamiento de la emision de los oxidos de nitrogeno (NO{sub x}) que se producen en el horno. El diseno del horno es modular, compuesto por seis secciones, las cuales se enfrian de forma independiente a traves de un sistema de control automatico, empleando una chaqueta de enfriamiento por la cual circula agua. Actualmente se han realizado tres encendidos hasta alcanzar su carga maxima de operacion, los resultados obtenidos muestran que el balance de energia global del horno experimental es practicamente el de diseno y cumple con las caracteristicas de tiempo de residencia y temperatura de gases a la salida del horno de Generadores de Vapor de gran capacidad.

  18. Thermodynamic methodology for the design of solar dryers operated with flat solar collectors; Metodologia termodinamica para el diseno de secadores operados con calentadores solares planos

    Energy Technology Data Exchange (ETDEWEB)

    Torres Reyes, Ernestina; Navarrete Gonzalez, Jose L; Ibarra Salazar, Beatriz A; Picon Nunez, Martin [Instituto de Investigaciones Cientificas, Universidad de Guanajuato, Guanjuato, Guanajuato (Mexico)

    2000-07-01

    In this paper a thermal performance analysis of solar drying process at operating varying conditions is presented. It is described semi-empirical models to thermal characterization of an experimental device. A simulator of thermal performance for operating varying conditions was developed as a part of the procedure of thermal design of solar dryers. On the other hand, it is described a simplified method to design solar collectors based on the determination of minimum entropy generation during the thermal conversion of the solar device by using the thermal analysis procedure established and the method derived of the second law of the Thermodynamics are finally presented. [Spanish] En este trabajo se presenta el analisis termico del comportamiento del sistema -colector solar camara de secado-. Se describen los modelos semi-empiricos con los que se caracterizo termicamente un secador solar experimental del tipo indirecto. Se presenta tambien un procedimiento de diseno de equipo de secado que toma en cuenta las condiciones variables de operacion que presentan los dispositivos solares. Por otro lado se describe un procedimiento simplificado de diseno, basado en un analisis derivado de la segunda ley de la Termodinamica. Esta metodologia se fundamenta en la minima generacion de entropia durante la conversion termica de la energia solar, utilizando colectores solares planos. Finalmente se presentan los resultados del diseno preliminar de equipo de secado utilizando los dos procedimientos mencionados.

  19. Fabrication of Wireless Micro Pressure Sensor Using the CMOS Process

    Directory of Open Access Journals (Sweden)

    Chienliu Chang

    2009-10-01

    Full Text Available In this study, we fabricated a wireless micro FET (field effect transistor pressure sensor based on the commercial CMOS (complementary metal oxide semiconductor process and a post-process. The wireless micro pressure sensor is composed of a FET pressure sensor, an oscillator, an amplifier and an antenna. The oscillator is adopted to generate an ac signal, and the amplifier is used to amplify the sensing signal of the pressure sensor. The antenna is utilized to transmit the output voltage of the pressure sensor to a receiver. The pressure sensor is constructed by 16 sensing cells in parallel. Each sensing cell contains an MOS (metal oxide semiconductor and a suspended membrane, which the gate of the MOS is the suspended membrane. The postprocess employs etchants to etch the sacrificial layers in the pressure sensor for releasing the suspended membranes, and a LPCVD (low pressure chemical vapor deposition parylene is adopted to seal the etch holes in the pressure. Experimental results show that the pressure sensor has a sensitivity of 0.08 mV/kPa in the pressure range of 0–500 kPa and a wireless transmission distance of 10 cm.

  20. Wide-band Polarization Splitter and Rotator with Large Fabrication Tolerance and Simple Fabrication Process

    DEFF Research Database (Denmark)

    Ding, Yunhong; Ou, Haiyan; Peucheret, Christophe

    2013-01-01

    We demonstrate a polarization splitter and rotator built on the silicon-on-insulator platform. The device shows low insertion loss (0.6 dB), low polarization crosstalk (<-12 dB), wide bandwidth (~100 nm), and large fabrication tolerance (60 nm).......We demonstrate a polarization splitter and rotator built on the silicon-on-insulator platform. The device shows low insertion loss (0.6 dB), low polarization crosstalk (fabrication tolerance (60 nm)....

  1. Wideband polarization splitter and rotator with large fabrication tolerance and simple fabrication process

    DEFF Research Database (Denmark)

    Ding, Yunhong; Ou, Haiyan; Peucheret, Christophe

    2013-01-01

    We propose and demonstrate a polarization splitter and rotator (PSR) built on a silicon-on-insulator platform. The PSR is constructed with a tapered waveguide followed by a 2×2 multimode interferometer and can be simply fabricated in a single lithography and etching step. A low insertion loss (....5  dB with minimum insertion loss of 0.6 dB) and a low polarization crosstalk (fabrication tolerance (>50  nm) are experimentally demonstrated....

  2. Finite Element Models for Electron Beam Freeform Fabrication Process

    Science.gov (United States)

    Chandra, Umesh

    2012-01-01

    Electron beam freeform fabrication (EBF3) is a member of an emerging class of direct manufacturing processes known as solid freeform fabrication (SFF); another member of the class is the laser deposition process. Successful application of the EBF3 process requires precise control of a number of process parameters such as the EB power, speed, and metal feed rate in order to ensure thermal management; good fusion between the substrate and the first layer and between successive layers; minimize part distortion and residual stresses; and control the microstructure of the finished product. This is the only effort thus far that has addressed computer simulation of the EBF3 process. The models developed in this effort can assist in reducing the number of trials in the laboratory or on the shop floor while making high-quality parts. With some modifications, their use can be further extended to the simulation of laser, TIG (tungsten inert gas), and other deposition processes. A solid mechanics-based finite element code, ABAQUS, was chosen as the primary engine in developing these models whereas a computational fluid dynamics (CFD) code, Fluent, was used in a support role. Several innovative concepts were developed, some of which are highlighted below. These concepts were implemented in a number of new computer models either in the form of stand-alone programs or as user subroutines for ABAQUS and Fluent codes. A database of thermo-physical, mechanical, fluid, and metallurgical properties of stainless steel 304 was developed. Computing models for Gaussian and raster modes of the electron beam heat input were developed. Also, new schemes were devised to account for the heat sink effect during the deposition process. These innovations, and others, lead to improved models for thermal management and prediction of transient/residual stresses and distortions. Two approaches for the prediction of microstructure were pursued. The first was an empirical approach involving the

  3. LAF-Fabric : Data processing for Linguistic Annotation Framework

    NARCIS (Netherlands)

    Roorda, Dirk

    2014-01-01

    LAF-fabric is a Python tool for running Python notebooks with access to the information in a LAF resource. The selling point of LAF-fabric is performance, both in terms of speed and memory usage. The second goal is to make it really easy for you to write analytic notebooks straightforwardly in terms

  4. Methodology for bioclimatic design; Metodologia para el diseno bioclimatico

    Energy Technology Data Exchange (ETDEWEB)

    Morillon Galvez, David [Instituto de Ingenieria de la UNAM, Mexico, D.F. (Mexico)

    2000-07-01

    A methodology for natural air conditioning of buildings is presented; bioclimatic architecture, in order to contribute to the suitable use of components of the building (walls, ceilings, floors, orientations, etc.) that when interacting with the environment takes advantage of it, without deterioration of the same, obtaining energy efficient designs. As well as an analysis of the elements and factors that the architecture must have to be sustainable; an adequate design to the environment, saving and efficient use of energy, the use of alternating energies by means of ecotechnologies and the self-sufficiency. [Spanish] Se presenta una metodologia para la climatizacion natural de edificios; arquitectura bioclimatica, con el objetivo de aportar al uso adecuado de componentes del edificio (muros, techos, pisos, orientaciones, etc.) que al interactuar con el ambiente tome ventaja de el, sin deterioro del mismo, logrando disenos energeticamente eficientes. Asi como un analisis de los elementos y factores que debe tener la arquitectura para ser sustentable; un diseno adecuado al ambiente, ahorro y uso eficiente de la energia, el uso de energias alternas mediante ecotecnologias y la autosuficiencia.

  5. Specialized hybrid batch fabrication process for MEMS RF voltage sensors

    Science.gov (United States)

    Dittmer, Jan; Judaschke, Rolf; Büttgenbach, Stephanus

    2007-12-01

    RF voltage measurement based on electrostatic RMS voltage-to-force conversion is an alternative method in comparison to the classical thermal power dissipation method. It is based on a parallel-plate capacitor with one elastically hinged plate. By applying an AC voltage, a force proportional to its RMS value is generated between the plates, and consequently the movable plate swings to the equilibrium position between spring force and electrostatic force. For a theoretically adequate resolution and precision, the necessary geometrical dimensions of the sensor practically require the use of advanced micromachining techniques. In this contribution, we discuss a unique batch fabrication process to meet the challenge of having two very large plane-parallel surfaces separated by only a few microns. The basic design consists of an actuator made of silicon embedded between two glass wafers for electrical contacting and sealing. Each step of this hybrid process has been optimized to prevent residual liquids leading to stiction and breaking of the fragile parts of the micro-structures. Flat grooves in the silicon define the gap between the capacitor electrodes, and an anisotropic dry-etch step releases the actuator. A second glass wafer builds the top of the stack and is fixated using a patterned photo-resist. Bumpers on the bottom layer and ridges in the top wafer improve the robustness of the structure. In this paper, we present a detailed analysis of the production process, pointing out critical as well as alternative design steps towards the optimized sensor. Finally, results of working devices are shown.

  6. IMPROVING KNITTED FABRICS BY A STATISTICAL CONTROL OF DIMENSIONAL CHANGES AFTER THE DYEING PROCESS

    OpenAIRE

    LLINARES-BERENGUER Jorge; DIAZ-GARCÍA Pablo; MIRÓ-MARTÍNEZ Pau

    2017-01-01

    One of the most important problems that cotton knitted fabrics present during the manufacturing process is their dimensional instability, which needs to be minimised. Some of the variables that intervene in fabric shrinkage are related with its structural characteristics, use of fiber when producing yarn, the yarn count used or the dyeing process employed. Conducted under real factory conditions, the present study attempted to model the behaviour of a fabric structure after a dyeing process b...

  7. Process for fabricating device structures for real-time process control of silicon doping

    Science.gov (United States)

    Weiner, Kurt H.

    2001-01-01

    Silicon device structures designed to allow measurement of important doping process parameters immediately after the doping step has occurred. The test structures are processed through contact formation using standard semiconductor fabrication techniques. After the contacts have been formed, the structures are covered by an oxide layer and an aluminum layer. The aluminum layer is then patterned to expose the contact pads and selected regions of the silicon to be doped. Doping is then performed, and the whole structure is annealed with a pulsed excimer laser. But laser annealing, unlike standard annealing techniques, does not effect the aluminum contacts because the laser light is reflected by the aluminum. Once the annealing process is complete, the structures can be probed, using standard techniques, to ascertain data about the doping step. Analysis of the data can be used to determine probable yield reductions due to improper execution of the doping step and thus provide real-time feedback during integrated circuit fabrication.

  8. Time effectiveness of capillary effect improvement of ramie fabrics processed by RF glow discharging

    International Nuclear Information System (INIS)

    Wang Zhiwen; Wei Weixing; He Yanhe; Zhao Yuanqing; Pan Liyiji; Li Xuemei; Shi Shaodui; Li Guangxin

    2010-01-01

    The time effectiveness of capillary effect improvement of ramie fabrics processed by RF glow discharging was studied. The ramie fabrics were processed in fulfilling with different gas (O 2 , N 2 , Ar) by different parameters (such as pressure,power and time) plasma. The capillary effect of the ramie fabrics processed by RF glow discharging was tested at different time. The results indicate that the capillary effect of ramie fabrics processed by RF glow discharging has been improved, the improvement of the capillary effect firstly decrease rapidly, then slowly, and become stable after 15 day, it indicate that improvement of the ramie fabrics capillary has good time effectiveness, and the plasma parameter for the best capillary effect improvement of ramie fabric is 100 W and 40 Pa processed 20 min by oxygen plasma. (authors)

  9. Bioinspired superhydrophobic surfaces, fabricated through simple and scalable roll-to-roll processing

    Science.gov (United States)

    Park, Sung-Hoon; Lee, Sangeui; Moreira, David; Bandaru, Prabhakar R.; Han, Intaek; Yun, Dong-Jin

    2015-10-01

    A simple, scalable, non-lithographic, technique for fabricating durable superhydrophobic (SH) surfaces, based on the fingering instabilities associated with non-Newtonian flow and shear tearing, has been developed. The high viscosity of the nanotube/elastomer paste has been exploited for the fabrication. The fabricated SH surfaces had the appearance of bristled shark skin and were robust with respect to mechanical forces. While flow instability is regarded as adverse to roll-coating processes for fabricating uniform films, we especially use the effect to create the SH surface. Along with their durability and self-cleaning capabilities, we have demonstrated drag reduction effects of the fabricated films through dynamic flow measurements.

  10. Bioinspired superhydrophobic surfaces, fabricated through simple and scalable roll-to-roll processing.

    Science.gov (United States)

    Park, Sung-Hoon; Lee, Sangeui; Moreira, David; Bandaru, Prabhakar R; Han, InTaek; Yun, Dong-Jin

    2015-10-22

    A simple, scalable, non-lithographic, technique for fabricating durable superhydrophobic (SH) surfaces, based on the fingering instabilities associated with non-Newtonian flow and shear tearing, has been developed. The high viscosity of the nanotube/elastomer paste has been exploited for the fabrication. The fabricated SH surfaces had the appearance of bristled shark skin and were robust with respect to mechanical forces. While flow instability is regarded as adverse to roll-coating processes for fabricating uniform films, we especially use the effect to create the SH surface. Along with their durability and self-cleaning capabilities, we have demonstrated drag reduction effects of the fabricated films through dynamic flow measurements.

  11. Multi-Step Deep Reactive Ion Etching Fabrication Process for Silicon-Based Terahertz Components

    Science.gov (United States)

    Jung-Kubiak, Cecile (Inventor); Reck, Theodore (Inventor); Chattopadhyay, Goutam (Inventor); Perez, Jose Vicente Siles (Inventor); Lin, Robert H. (Inventor); Mehdi, Imran (Inventor); Lee, Choonsup (Inventor); Cooper, Ken B. (Inventor); Peralta, Alejandro (Inventor)

    2016-01-01

    A multi-step silicon etching process has been developed to fabricate silicon-based terahertz (THz) waveguide components. This technique provides precise dimensional control across multiple etch depths with batch processing capabilities. Nonlinear and passive components such as mixers and multipliers waveguides, hybrids, OMTs and twists have been fabricated and integrated into a small silicon package. This fabrication technique enables a wafer-stacking architecture to provide ultra-compact multi-pixel receiver front-ends in the THz range.

  12. Application of foams to the processing of fabrics. Final report, October 1, 1977-September 30, 1981

    Energy Technology Data Exchange (ETDEWEB)

    Namboodri, C.G.

    1981-10-01

    The primary objective of this project was to reduce the energy consumed in the wet processing of fabrics where wet processing encompasses those processes used to convert loomstate (greige) goods to finished textile products. This includes desizing, scouring, bleaching, dyeing, printing, and finishing of fabrics. The energy intensive step in most of these processes is drying the fabric. By having less water on the fabric as it enters a drying oven, proportionately less energy is consumed in drying the fabric. The specific route used in this project to accomplish this objective has been to use air to distribute the finish, dye or printing ink onto the fabric. Rather than saturating the fabric with a dilute finish formulation, a concentrated formulation is mechanically foamed, air serving as the diluting medium and the foam applied to the fabric. In this manner, the water content of the fabric as it enters the drying oven is reduced by as much as 80% thereby leading to a corresponding reduction in the energy required to dry the fabric. Details on the procedure are presented and experimental results are discussed. (MCW)

  13. Electrochromic Windows: Process and Fabrication Improvements for Lower Total Costs

    Energy Technology Data Exchange (ETDEWEB)

    Mark Burdis; Neil Sbar

    2007-03-31

    The overall goal with respect to the U.S. Department of Energy (DOE) is to achieve significant national energy savings through maximized penetration of EC windows into existing markets so that the largest cumulative energy reduction can be realized. The speed with which EC windows can be introduced and replace current IGU's (and current glazings) is clearly a strong function of cost. Therefore, the aim of this project was to investigate possible improvements to the SageGlass{reg_sign} EC glazing products to facilitate both process and fabrication improvements resulting in lower overall costs. The project was split into four major areas dealing with improvements to the electrochromic layer, the capping layer, defect elimination and general product improvements. Significant advancements have been made in each of the four areas. These can be summarized as follows: (1) Plasma assisted deposition for the electrochromic layer was pursued, and several improvements made to the technology for producing a plasma beam were made. Functional EC devices were produced using the new technology, but there are still questions to be answered regarding the intrinsic properties of the electrochromic films produced by this method. (2) The capping layer work was successfully implemented into the existing SageGlass{reg_sign} product, thereby providing a higher level of transparency and somewhat lower reflectivity than the 'standard' product. (3) Defect elimination is an ongoing effort, but this project spurred some major defect reduction programs, which led to significant improvements in yield, with all the implicit benefits afforded. In particular, major advances were made in the development of a new bus bar application process aimed at reducing the numbers of 'shorts' developed in the finished product, as well as making dramatic improvements in the methods used for tempering the glass, which had previously been seen to produce a defect which appeared as a

  14. State of the art in the process design of large sea water desalination plants; Estado del arte en el diseno del proceso de plantas desaladoras de agua de mar de gran capacidad

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez Sanchez, J. M.; Sanchez Castillo, N.; Sanchez Castillo, R.

    2008-07-01

    The desalination of seawater is used in commercial operations worldwide in order to obtain large quantities of proper water for population supply, irrigation or industrial uses. The designs of the processes which are involved in desalination are changing all the time. In this paper the evolution of the processes of seawater desalination plants will be discussed. It will focus on large Reverse Osmosis desalination plants: also it will discuss the reasons of this evolution. (Author) 8 refs.

  15. Optimization benefits analysis in production process of fabrication components

    Science.gov (United States)

    Prasetyani, R.; Rafsanjani, A. Y.; Rimantho, D.

    2017-12-01

    The determination of an optimal number of product combinations is important. The main problem at part and service department in PT. United Tractors Pandu Engineering (shortened to PT.UTPE) Is the optimization of the combination of fabrication component products (known as Liner Plate) which influence to the profit that will be obtained by the company. Liner Plate is a fabrication component that serves as a protector of core structure for heavy duty attachment, such as HD Vessel, HD Bucket, HD Shovel, and HD Blade. The graph of liner plate sales from January to December 2016 has fluctuated and there is no direct conclusion about the optimization of production of such fabrication components. The optimal product combination can be achieved by calculating and plotting the amount of production output and input appropriately. The method that used in this study is linear programming methods with primal, dual, and sensitivity analysis using QM software for Windows to obtain optimal fabrication components. In the optimal combination of components, PT. UTPE provide the profit increase of Rp. 105,285,000.00 for a total of Rp. 3,046,525,000.00 per month and the production of a total combination of 71 units per unit variance per month.

  16. Obtention process of phosphorus 32 starting from commercial sulfur and design and construction of the radiochemical separation prototype; Proceso de obtencion de fosforo-32 a partir de azufre comercial y diseno y construccion del prototipo de separacion radioquimica

    Energy Technology Data Exchange (ETDEWEB)

    Duarte A, C.; Alanis M, J.; Gutierrez R, C. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    2002-07-01

    In this work an obtention process of phosphorus 32 ({sup 32} P) in orthophosphoric acid form (H{sub 3}{sup 32}PO{sub 4}) is described starting from commercial sulfur. Also the design and construction of the experimental prototype used in the radiochemical separation and their results in three tests carried out is reported. (Author)

  17. Design and energy analysis of a electrolytic hydrogen production process by means of a high temperature nuclear reactor; Diseno y analisis energetico de un proceso de produccion de hidrogeno electrolitico por medio de un reactor nuclear de alta temperatura

    Energy Technology Data Exchange (ETDEWEB)

    Valle H, J.; Morales S, J. B. [UNAM, DEPFI Campus Morelos, Jiutepec, Morelos (Mexico)]. e-mail: julfi_jg@yahoo.com.mx

    2008-07-01

    In this work an energy analysis to a process of production of hydrogen by means of electrolysis of high temperature is realized. This electrolysis type, unlike conventional electrolysis allows us to reach efficiencies of up to 60% because when increasing the temperature of the water, providing to its thermal energy, diminishes the demand of electrical energy required to separate the molecule of the water. Nevertheless, to obtain these efficiencies it is needed to have superheated aqueous vapor to but of 850 centigrade degrees, temperatures that can be reached about high temperature reactor; HTGR. In the present work it is mentioned to introduction way the importance of the hydrogen like energy vector and the advantages of obtaining it by means of nuclear energy. The electrolysis process of high temperature is described and a design is realized of this from its coupling to a nuclear power plant PBMR. The technological advances on which it counts the PBMR; efficiencies of 48% for optimized plants, their modular design and the thermodynamic cycle recuperative Brayton where upon operate; make the short term ideal candidate for the production of hydrogen. The thermodynamic analysis of optimized plant PBMR appears in another work, here the results of the balance of mass and energy involved in the process appear of hydrogen generation and the complete analysis of this. The result is a complete model of generation of hydrogen by electrolysis of high temperature coupled to an optimized plant PBMR that will be implemented for its dynamic simulation later. (Author)

  18. Process and device for fabricating nuclear fuel assembly grids

    International Nuclear Information System (INIS)

    Thiebaut, B.; Duthoo, D.; Germanaz, J.J.; Angilbert, B.

    1991-01-01

    The method for fabricating PWR fuel assembly grids consists to place the grid of which the constituent parts are held firmly in place within a frame into a sealed chamber full of inert gas. This chamber can rotate about an axis. The welding on one face at a time is carried out with a laser beam orthogonal to the axis orientation of the device. The laser source is outside of the chamber and the beam penetrates via a transparent view port

  19. Novel magnetic wire fabrication process by way of nanoimprint lithography for current induced magnetization switching

    Directory of Open Access Journals (Sweden)

    Tsukasa Asari

    2017-05-01

    Full Text Available Nanoimprint lithography (NIL is an effective method to fabricate nanowire because it does not need expensive systems and this process is easier than conventional processes. In this letter, we report the Current Induced Magnetization Switching (CIMS in perpendicularly magnetized Tb-Co alloy nanowire fabricated by NIL. The CIMS in Tb-Co alloy wire was observed by using current pulse under in-plane external magnetic field (HL. We successfully observed the CIMS in Tb-Co wire fabricated by NIL. Additionally, we found that the critical current density (Jc for the CIMS in the Tb-Co wire fabricated by NIL is 4 times smaller than that fabricated by conventional lift-off process under HL = 200Oe. These results indicate that the NIL is effective method for the CIMS.

  20. Novel magnetic wire fabrication process by way of nanoimprint lithography for current induced magnetization switching

    Science.gov (United States)

    Asari, Tsukasa; Shibata, Ryosuke; Awano, Hiroyuki

    2017-05-01

    Nanoimprint lithography (NIL) is an effective method to fabricate nanowire because it does not need expensive systems and this process is easier than conventional processes. In this letter, we report the Current Induced Magnetization Switching (CIMS) in perpendicularly magnetized Tb-Co alloy nanowire fabricated by NIL. The CIMS in Tb-Co alloy wire was observed by using current pulse under in-plane external magnetic field (HL). We successfully observed the CIMS in Tb-Co wire fabricated by NIL. Additionally, we found that the critical current density (Jc) for the CIMS in the Tb-Co wire fabricated by NIL is 4 times smaller than that fabricated by conventional lift-off process under HL = 200Oe. These results indicate that the NIL is effective method for the CIMS.

  1. Methodology Einstein for energy audit and design of solar heat systems in industrial processes; Metodologia Einstein para auditoria energetica y diseno de sistemas de calor solar en procesos industriales

    Energy Technology Data Exchange (ETDEWEB)

    Schweiger, H.; Vannoni, C.; Danov, S.; Facci, E.

    2008-07-01

    Estimates show that 57% of the total industrial heat demand in EU countries is required at low (up to 100 degree centigrade) and medium temperature (up to 400 degree centigrade). An important part of this thermal energy demand can be covered by solar thermal energy. In the framework of the European project EINSTEIN (Expert-system for an Intelligent Supply of Thermal Energy in Industry), an expert system is being developed, where process optimisation, heat recovery, intelligent cold supply and renewable energy are integrated into a holistic energy audit methodology with the objective of reducing energy consumption in the industrial sector. EINSTEIN is being developed as a free and open source software project. (Author)

  2. Refabrication of spent fuel pins provided with instrumentation by means of the FABRICE process

    International Nuclear Information System (INIS)

    Garcia, A.; Malard, J.P.; Mery, M.; Vouillot, M.

    1986-05-01

    The Fabrice ''hot cell refabrication'' process for small pins from very long irradiated fuel elements was developed at the CEA to allow parametic studies of the irradiation behavior of pins from nuclear power plants. The present note describes the adaptation of techniques to the fabrication of pins provided with important instrumentations [fr

  3. Processing and characterization of multilayers for energy device fabrication (invited)

    DEFF Research Database (Denmark)

    Kaiser, Andreas; Kiebach, Wolff-Ragnar; Gurauskis, Jonas

    /catalytic layers.  Optical dilatometry has proven to be a powerful and fast tool to optimize the co-sintering of planar, asymmetric multilayers, consisting of a porous support and a dense membrane layer. The monitoring of dimensional changes and distortions in single and multilayers during de-binding and sintering......The performance of asymmetric multilayer structures in solid oxide fuel cells (SOFC)/solid oxide electrolysis cells (SOEC), tubular oxygen transport membranes (OTM) and similar high temperature energy devices is often determined by the ceramic fabrication (for given materials and design). A good...

  4. Lithium zirconate elements fabricated by industrial scale processes

    International Nuclear Information System (INIS)

    Roux, N.

    1991-01-01

    Lithium metazirconate Li 2 ZrO 3 is one of the leading tritium breeding ceramics contemplated in solid blanket concepts for fusion reactors. Among its merits are fair physical properties, satisfactory compatibility with structural materials and beryllium, satisfactory mechanical strength, excellent irradiation behaviour as shown by a comparative irradiation of ceramics in the EBR II reactor, and very good tritium release performance as evidenced in the MOZART and EXOTIC neutron irradiations. Pechiney and the CEA are jointly involved in developing industrial fabrication of Li 2 ZrO 3 elements to the microstructural and geometrical specifications required for their use in the solid blankets as conceived in the European Program

  5. IMPROVING KNITTED FABRICS BY A STATISTICAL CONTROL OF DIMENSIONAL CHANGES AFTER THE DYEING PROCESS

    Directory of Open Access Journals (Sweden)

    LLINARES-BERENGUER Jorge

    2017-05-01

    Full Text Available One of the most important problems that cotton knitted fabrics present during the manufacturing process is their dimensional instability, which needs to be minimised. Some of the variables that intervene in fabric shrinkage are related with its structural characteristics, use of fiber when producing yarn, the yarn count used or the dyeing process employed. Conducted under real factory conditions, the present study attempted to model the behaviour of a fabric structure after a dyeing process by contributing several algorithms that calculate dyed fabric stability after the first wash cycle. Small-diameter circular machines are used to produce garments with no side seams. This is the reason why a list of machines that produce the same fabrics for different widths needs to be made available to produce all the sizes of a given garment. Two relaxation states were distingued for interlock fabric: dyed and dry relaxation, and dyed and wash relaxation. The linear density of the yarn employed to produce sample fabric was combed cotton Ne 30. The machines used for optic bleaching were Overflow. To obtain knitting structures with optimum dimensional stability, different statistical tools were used to help us to evaluate all the production process variables (raw material, machines and process responsible for this variation. This allowed to guarantee product quality without creating costs and losses.

  6. Application of the Pinch analysis for the design of a cogeneration system in a paper mill; Aplicacion del analisis Pinch para el diseno de un sistema de cogeneracion en una industria papelera

    Energy Technology Data Exchange (ETDEWEB)

    Mani Gonzalez, A. G.; Arriola Medellin, A. [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1997-12-31

    The Pinch Analysis is a set of principles, tools and rules for the design that allow the engineer find the best way to configure the elements of a process. In the last ten years it has been utilized for the design of new processes as well as in the energy optimization of existing processes. In this paper the tools utilized for the integration of a cogeneration system in a process for the production of paper is presented. It is also presented how the combined treatment of the Pinch Analysis and the exergy concept allows to define, before the detailed design, the cogeneration potential, the fuel consumption and the amount of pollutant emissions for different cogeneration schemes. [Espanol] El analisis Pinch es un conjunto de principios, herramientas y reglas de diseno que permiten al ingeniero encontrar la mejor manera de configurar los elementos de un proceso. En los ultimos diez anos se ha utilizado para el diseno de procesos nuevos asi como en la optimacion energetica de procesos existentes. En el presente articulo se presentan las herramientas utilizadas para la integracion de un sistema de cogeneracion en un proceso de produccion de papel. Se muestra tambien como el tratamiento combinado del analisis Pinch y el concepto de energia permite definir, antes del diseno detallado, el potencial de cogeneracion, el consumo de combustible y la cantidad de emisiones contaminantes para diferentes esquemas de cogeneracion.

  7. Fabrication Process and Reliability Evaluation of Shape Memory Alloy Composite

    International Nuclear Information System (INIS)

    Lee, Jin Kyung; Choi, Il Kook; Park, Young Chul; Lee, Kyu Chang; Lee, Joon Hyun

    2001-01-01

    Shape memory alloy has been used to improve the tensile strength of composite by the occurrence of compressive residual stress in matrix using its shape memory effect. In order to fabricate shape memory alloy composite, TiNi alloy and A16061 were used as reinforcing material and mix, respectively. In this study, TiNi/A16061 shape memory alloy composite was made by using hot press method. However, the specimen fabricated by this method had the bonding problem at the boundary between TiNi fiber and Al matrix when the load was applied to it. A cold rolling was imposed to the specimen to improve the bonding effect. It was found that tensile strength of specimen subjected to cold rolling was more increased than that of specimen which did not underwent cold rolling. In addition, acoustic emission technique was used to quantify the microscopic damage behavior of cold rolled TiNi/A16061 shape memory alloy composite at high temperature

  8. Closed-Loop Process Control for Electron Beam Freeform Fabrication and Deposition Processes

    Science.gov (United States)

    Taminger, Karen M. (Inventor); Hafley, Robert A. (Inventor); Martin, Richard E. (Inventor); Hofmeister, William H. (Inventor)

    2013-01-01

    A closed-loop control method for an electron beam freeform fabrication (EBF(sup 3)) process includes detecting a feature of interest during the process using a sensor(s), continuously evaluating the feature of interest to determine, in real time, a change occurring therein, and automatically modifying control parameters to control the EBF(sup 3) process. An apparatus provides closed-loop control method of the process, and includes an electron gun for generating an electron beam, a wire feeder for feeding a wire toward a substrate, wherein the wire is melted and progressively deposited in layers onto the substrate, a sensor(s), and a host machine. The sensor(s) measure the feature of interest during the process, and the host machine continuously evaluates the feature of interest to determine, in real time, a change occurring therein. The host machine automatically modifies control parameters to the EBF(sup 3) apparatus to control the EBF(sup 3) process in a closed-loop manner.

  9. Process chain for fabrication of anisotropic optical functional surfaces on polymer components

    DEFF Research Database (Denmark)

    Li, Dongya; Zhang, Yang; Regi, Francesco

    2017-01-01

    This paper aims to introduce a process chain for fabrication of anisotropic optical functional surfaces on polymer products. Thesurface features under investigation are composed of micro serrated ridges. The scope was to maximize the visible contrast betweenhorizontally orthogonal textured surfaces...

  10. Biomimetic architectures by plasma processing fabrication and applications

    CERN Document Server

    Chattopadhyay, Surojit

    2014-01-01

    Photonic structures in the animal kingdom: valuable inspirations for bio-mimetic applications. Moth eye-type anti-reflecting nanostructures by an electron cyclotron resonance plasma. Plasma-processed biomimetic nano/microstructures. Wetting properties of natural and plasma processed biomimetic surfaces. Biomimetic superhydrophobic surface by plasma processing. Biomimetic interfaces of plasma modified titanium alloy.

  11. Application of foams to the processing of fabrics. Interim report, October 1, 1977-March 31, 1979

    Energy Technology Data Exchange (ETDEWEB)

    Duke, M.W.

    1979-04-01

    The primary objective of this project is to reduce the energy requirements for finishing fabrics by drastically reducing the water required to wet process the fabrics. Since less water is used, less energy is consumed in the evaporation of water. This is accomplished by replacing much of the water with air, making a foam and using it as the application medium. In the first six months of the project the practicality of foam fabric finishing on a commercial basis had been established. Limited yardage of fabrics equivalent in performance to conventionally wet finished fabrics were processed. In these mill trials, a range of foam fabric finishes including softeners, hand builders, durable press and shrink-resistant types were applied to cotton sheeting, corduroy and polyester/cellulosic blends, etc. In all cases, substantial energy savings were realized. Since the issuance of the first and second interim reports, commercial practice of foam fabric finishing continues to grow with cumulative total estimated as approaching 200,000,000 yards. A number of companies are currently using foam fabric finishing as a commercial production process. Additionally, the pilot range has been used to demonstrate foam fabric finishing to over twenty companies. The range has been used to demonstrate the foam acid dyeing of nylon carpets to several companies in this specialized area of textile processing. Active work still continues with these companies since the foam dyeing of carpets involves only about 1/5 the water used in the normal continuous dyeing of carpets. At the time of writing two carpet companies are actively working to evaluate foam dyeing on a mill scale. (LCL)

  12. A full description of a simple and scalable fabrication process for electrowetting displays

    International Nuclear Information System (INIS)

    Zhou, K; Heikenfeld, J; Dean, K A; Howard, E M; Johnson, M R

    2009-01-01

    Electrowetting displays provide a high white state reflectance of >50% and have attracted substantial world-wide interest, yet are primarily an industrially led effort with few details on preferred materials and fabrication processes. Reported herein is the first complete description of the electrowetting display fabrication process. The description includes materials selection, purification and all fabrication steps from substrate selection to sealing. Challenging materials and fabrication processes include dielectric optimization, fluoropolymer selection, hydrophilic grid patterning, liquid dosing, dye purification and liquid ionic content. The process described herein has produced pixel arrays that were switched at 2 . The majority of fabrication processes can conform to liquid-crystal style manufacturing equipment, and therefore can be readily adopted by many display practitioners. Also presented are additional tips and techniques, such as controlling the onset of oil film break-up in an electrowetting display. This paper should enable anyone skilled in displays or microfabrication to quickly and successfully set up research and fabrication of electrowetting displays

  13. Screen printing of a capacitive cantilever-based motion sensor on fabric using a novel sacrificial layer process for smart fabric applications

    International Nuclear Information System (INIS)

    Wei, Yang; Torah, Russel; Yang, Kai; Beeby, Steve; Tudor, John

    2013-01-01

    Free-standing cantilevers have been fabricated by screen printing sacrificial and structural layers onto a standard polyester cotton fabric. By printing additional conductive layers, a complete capacitive motion sensor on fabric using only screen printing has been fabricated. This type of free-standing structure cannot currently be fabricated using conventional fabric manufacturing processes. In addition, compared to conventional smart fabric fabrication processes (e.g. weaving and knitting), screen printing offers the advantages of geometric design flexibility and the ability to simultaneously print multiple devices of the same or different designs. Furthermore, a range of active inks exists from the printed electronics industry which can potentially be applied to create many types of smart fabric. Four cantilevers with different lengths have been printed on fabric using a five-layer structure with a sacrificial material underneath the cantilever. The sacrificial layer is subsequently removed at 160 °C for 30 min to achieve a freestanding cantilever above the fabric. Two silver electrodes, one on top of the cantilever and the other on top of the fabric, are used to capacitively detect the movement of the cantilever. In this way, an entirely printed motion sensor is produced on a standard fabric. The motion sensor was initially tested on an electromechanical shaker rig at a low frequency range to examine the linearity and the sensitivity of each design. Then, these sensors were individually attached to a moving human forearm to evaluate more representative results. A commercial accelerometer (Microstrain G-link) was mounted alongside for comparison. The printed sensors have a similar motion response to the commercial accelerometer, demonstrating the potential of a printed smart fabric motion sensor for use in intelligent clothing applications. (paper)

  14. Screen printing of a capacitive cantilever-based motion sensor on fabric using a novel sacrificial layer process for smart fabric applications

    Science.gov (United States)

    Wei, Yang; Torah, Russel; Yang, Kai; Beeby, Steve; Tudor, John

    2013-07-01

    Free-standing cantilevers have been fabricated by screen printing sacrificial and structural layers onto a standard polyester cotton fabric. By printing additional conductive layers, a complete capacitive motion sensor on fabric using only screen printing has been fabricated. This type of free-standing structure cannot currently be fabricated using conventional fabric manufacturing processes. In addition, compared to conventional smart fabric fabrication processes (e.g. weaving and knitting), screen printing offers the advantages of geometric design flexibility and the ability to simultaneously print multiple devices of the same or different designs. Furthermore, a range of active inks exists from the printed electronics industry which can potentially be applied to create many types of smart fabric. Four cantilevers with different lengths have been printed on fabric using a five-layer structure with a sacrificial material underneath the cantilever. The sacrificial layer is subsequently removed at 160 °C for 30 min to achieve a freestanding cantilever above the fabric. Two silver electrodes, one on top of the cantilever and the other on top of the fabric, are used to capacitively detect the movement of the cantilever. In this way, an entirely printed motion sensor is produced on a standard fabric. The motion sensor was initially tested on an electromechanical shaker rig at a low frequency range to examine the linearity and the sensitivity of each design. Then, these sensors were individually attached to a moving human forearm to evaluate more representative results. A commercial accelerometer (Microstrain G-link) was mounted alongside for comparison. The printed sensors have a similar motion response to the commercial accelerometer, demonstrating the potential of a printed smart fabric motion sensor for use in intelligent clothing applications.

  15. Enhanced fabrication process of zinc oxide nanowires for optoelectronics

    Energy Technology Data Exchange (ETDEWEB)

    García Núñez, C., E-mail: carlos.garcia@uam.es [Grupo de Electrónica y Semiconductores, Departamento de Física Aplicada, Universidad Autónoma de Madrid, 28049 Madrid (Spain); Pau, J.L.; Ruíz, E.; García Marín, A.; García, B.J.; Piqueras, J. [Grupo de Electrónica y Semiconductores, Departamento de Física Aplicada, Universidad Autónoma de Madrid, 28049 Madrid (Spain); Shen, G.; Wilbert, D.S.; Kim, S.M.; Kung, P. [Department of Electrical and Computer Engineering, the University of Alabama, Tuscaloosa, AL 35487 (United States)

    2014-03-31

    Zinc oxide (ZnO) nanowires (NWs) based ultraviolet (UV) sensors have been fabricated using different assembly techniques to form functional structures, aiming at the improvement of the performance of NW-based sensors for optoelectronic applications. NWs with diameters and lengths varying between 90–870 nm and 2–20 μm, respectively, were synthesized by controlling the growth conditions in a chemical vapor transport system. Optical properties of NWs were studied by means of transmission spectroscopy. Electrical properties of single ZnO NW-based sensors were analyzed in dark and under UV illumination (at photon wavelength of λ < 370 nm) as a function of the NW diameter. Results of the study indicate that reduction of the NW diameter below 200 nm leads to an improvement of the photocurrent (at λ < 370 nm) up to 10{sup 2} μA and a decrease of the decay time around 150 s. These enhancements may help to improve the performance of ZnO-based optoelectronic devices. - Highlights: • ZnO nanowires (NWs) with diameters 90–870 nm were grown by chemical vapor transport. • ZnO NWs showed strong absorption in the UV range. • Different assembly techniques were tested for preparing ZnO NW-based UV sensors. • Sensor photoresponses were around 10{sup 3} A/W. • Reducing NW diameter below 200 nm improved sensor photosensitivity.

  16. Fission product behaviors in spent fuel materials during DUPIC fuel fabrication process

    International Nuclear Information System (INIS)

    Kim, J. H.; Na, S. H.; Lee, J. H.; Yang, M. S.

    2002-01-01

    In order to obtain the fundamental data for the analysis of fission product behaviors during DUPIC fuel fabrication process, which is to convert spent PWR fuel into CANDU reactor fuel, the measurement system of radioactivity in spent fuel materials by gamma spectrometry technique was installed in IMEF M6 hot cell,and the preliminary analysis on the release behaviors of fission gas during the DUPIC fuel fabrication process were conducted. Based on the radioactivity measurement for the spent oxidized powder, green pellet and the sintered pellet produced from DUPIC fabrication process, it was found that little Cs-137 was released during OREOX process, but almost 99% of Cs-137 was released during sintering process. The release rate of both Zr-95 and Ru-103 was not so high during sintering process

  17. Thermal and radiation process for nano-/micro-fabrication of crosslinked PTFE

    International Nuclear Information System (INIS)

    Kobayashi, Akinobu; Oshima, Akihiro; Okubo, Satoshi; Tsubokura, Hidehiro; Takahashi, Tomohiro; Oyama, Tomoko Gowa; Tagawa, Seiichi; Washio, Masakazu

    2013-01-01

    Nano-/micro-fabrication process of crosslinked poly(tetrafluoroethylene) (RX-PTFE) is proposed as a novel method using combined process which is thermal and radiation process for fabrication of RX-PTFE (TRaf process). Nano- and micro-scale patterns of silicon wafers fabricated by EB lithography were used as the molds for TRaf process. Poly(tetrafluoroethylene) (PTFE) dispersion was dropped on the fabricated molds, and then PTFE was crosslinked with doses from 105 kGy to 1500 kGy in its molten state at 340 °C in nitrogen atmosphere. The obtained nano- and micro-structures by TRaf process were compared with those by the conventional thermal fabrication process. Average surface roughness (R a ) of obtained structures was evaluated with atomic force microscope (AFM) and scanning electron microscope (SEM). R a of obtained structures with the crosslinking dose of 600 kGy showed less than 1.2 nm. The fine nano-/micro-structures of crosslinked PTFE were successfully obtained by TRaf process

  18. Intelligent buildings vs. bioclimatic design; Edificios inteligentes vs. diseno bioclimatico

    Energy Technology Data Exchange (ETDEWEB)

    Aguayo Gonzalez, Ricardo [Tecnologico de Monterrey (Mexico)

    2006-10-15

    Present the form of intelligent buildings designing is the article purpose. Those kinds of edifications take advantage of climatic conditions which allow the users comfort and the efficient electric power use, avoiding the polluting agents. It also shows the four next following stages to design an intelligent building to know: the dry weather and relative dampness schedule variations during a year in the building location; the predominant winds direction, intensity and schedule frequency; the cloudiness, rain, etc and how to use the Givoni diagram to obtain the natural air-conditioning strategies and reach the thermal comfort. [Spanish] El proposito de este articulo es presentar la forma de disenar edificios Inteligentes, los cuales aprovechan las condiciones climaticas que permiten el confort de los usuarios y el uso eficiente de la energia electrica, evitando asi la emision de agentes contaminantes. Tambien menciona los siguientes cuatro pasos para el diseno de un edificio inteligente: conocer las variaciones horarias de temperatura seca y humedad relativa durante un ano en el lugar donde estara el edificio, saber la direccion, intensidad y frecuencia horaria de los vientos dominantes, tener conocimiento de la nubosidad, lluvia, etc. y utilizar el diagrama de Givoni para obtener las estrategias de climatizacion natural para obtener el confort termico.

  19. Comparison of Color and Fabric Presentation Options in the Design Process

    OpenAIRE

    Jackson, Reneé Susan

    2000-01-01

    The purpose of this research was to assess the current (manual) and future (automated) presentation options for fabric and color in the design process. Current and future presentation options were assessed for viability and identification of relationships between reported sufficiency levels and recommended use responses. This exploration was used to identify new and future technologies for presentation of fabric and color that could potentially aid in increasing product manufacturing competit...

  20. More steps towards process automation for optical fabrication

    Science.gov (United States)

    Walker, David; Yu, Guoyu; Beaucamp, Anthony; Bibby, Matt; Li, Hongyu; McCluskey, Lee; Petrovic, Sanja; Reynolds, Christina

    2017-06-01

    In the context of Industrie 4.0, we have previously described the roles of robots in optical processing, and their complementarity with classical CNC machines, providing both processing and automation functions. After having demonstrated robotic moving of parts between a CNC polisher and metrology station, and auto-fringe-acquisition, we have moved on to automate the wash-down operation. This is part of a wider strategy we describe in this paper, leading towards automating the decision-making operations required before and throughout an optical manufacturing cycle.

  1. Impact of process temperature on GaSb metal-oxide-semiconductor interface properties fabricated by ex-situ process

    Science.gov (United States)

    Yokoyama, Masafumi; Asakura, Yuji; Yokoyama, Haruki; Takenaka, Mitsuru; Takagi, Shinichi

    2014-06-01

    We have studied the impact of process temperature on interface properties of GaSb metal-oxide-semiconductor (MOS) structures fabricated by an ex-situ atomic-layer-deposition (ALD) process. We have found that the ALD temperature strongly affects the Al2O3/GaSb MOS interface properties. The Al2O3/GaSb MOS interfaces fabricated at the low ALD temperature of 150 °C have the minimum interface-trap density (Dit) of ˜4.5 × 1013 cm-2 eV-1. We have also found that the post-metalization annealing at temperature higher than 200 °C degrades the Al2O3/GaSb MOS interface properties. The low-temperature process is preferable in fabricating GaSb MOS interfaces in the ex-situ ALD process to avoid the high-temperature-induced degradations.

  2. Relationship between single-event upset immunity and fabrication processes of recent memories

    International Nuclear Information System (INIS)

    Nemoto, N.; Shindou, H.; Kuboyama, S.; Matsuda, S.; Itoh, H.; Okada, S.; Nashiyama, I.

    1999-01-01

    Single-Event upset (SEU) immunity for commercial devices were evaluated by irradiation tests using high-energy heavy ions. We show test results and describe the relationship between observed SEU and structures/fabrication processes. We have evaluated single-even upset (SEU) tolerance of recent commercial memory devices using high energy heavy ions in order to find relationship between SEU rate and their fabrication process. It was revealed that the change of the process parameter gives much effect for the SEU rate of the devices. (authors)

  3. Silicon Nano fabrication by Atomic Force Microscopy-Based Mechanical Processing

    International Nuclear Information System (INIS)

    Miyake, Sh.; Wang, M.; Kim, J.

    2014-01-01

    This paper reviews silicon nano fabrication processes using atomic force microscopy (AFM). In particular, it summarizes recent results obtained in our research group regarding AFM-based silicon nano fabrication through mechanochemical local oxidation by diamond tip sliding, as well as mechanical, electrical, and electromechanical processing using an electrically conductive diamond tip. Microscopic three-dimensional manufacturing mainly relies on etching, deposition, and lithography. Therefore, a special emphasis was placed on nano mechanical processes, mechanochemical reaction by potassium hydroxide solution etching, and mechanical and electrical approaches. Several important surface characterization techniques consisting of scanning tunneling microscopy and related techniques, such as scanning probe microscopy and AFM, were also discussed.

  4. Re-qualification of MTR-type fuel plates fabrication process

    International Nuclear Information System (INIS)

    Elseaidy, I.M.; Ghoneim, M.M.

    2010-01-01

    The fabricability issues with increased uranium loading due to use low enrichment of uranium (LEU), i.e. less than 20 % of U 235 , increase the problems which occur during compact manufacturing, roll bonding of the fuel plates, potential difficulty in forming during rolling process, mechanical integrity of the core during fabrication, potential difficulty in meat homogeneity, and the ability to fabricate plates with thicker core as a means of increasing total uranium loading. To produce MTR- type fuel plates with high uranium loading (HUL) and keep the required quality of these plates, many of qualification process must be done in the commissioning step of fuel fabrication plant. After that any changing of the fabrication parameters, for example changing of any of the raw materials, devises, operators, and etc., a re- qualification process should be done in order to keep the quality of produced plates. Objective of the present work is the general description of the activities to be accomplished for re-qualification of manufacturing MTR- type nuclear fuel plates. For each process to be re-qualified, a detailed of re-qualification process were established. (author)

  5. TOWARD LOW-COST FABRICATION OF MICROCHANNEL PROCESS TECHNOLOGIES - COST MODELING FOR MANUFACTURING DEVELOPMENT

    Energy Technology Data Exchange (ETDEWEB)

    Leith, Steven D.; King, Dale A.; Paul, Brian

    2010-11-07

    Chemical and energy conversion systems based on microchannel process technology (MPT) demonstrate high performance in applications in which rates are controlled by diffusive heat and mass transfer flux. The performance of MPT-based heat exchangers, absorbers/desorbers and chemical reactors all benefit from process intensification and have been used in a variety of mobile energy conversion systems including fuel reformers/converters, heat pumps and waste heat scavenging technologies. The service environments typical of MPTs often require the devices to be fabricated from metals such as aluminum, titanium, stainless steel or high temperature super alloys. Flow channels and associated critical dimensions in these devices can be as small as 50 um, but generally range from 100 to 1000 um in width and height with characteristic flow channel lengths normally in the mm to cm range. High surface area architectures (e.g. wicks or textured surfaces) are often included in the flow channels as well for enhanced mass transfer and/or catalytic functionality. Fabrication of MPT devices has historically been performed using a stacked-shim approach in which individual metal sheets are first patterned with micro- and meso-scale flow channels and subsequently bonded in a stack to create an array of miniaturized, parallel flow paths. Typical proof-of-concept fabrication efforts have utilized photo chemical machining (PCM) for shim patterning and diffusion bonding or diffusion brazing for joining of shim stacks. While flexible and capable of supporting technology demonstration, however, these techniques can be expensive at prototyping volumes. The high fabrication cost associated with these prototyping processes has contributed to a perception that MPT technology is expensive and will be relegated to a small application space. Recent work at the Microproducts Breakthrough Institute (MBI) has focused on exploring the cost structure of high volume manufacturing of MPT devices in effort to

  6. A New Fabrication Process for Thin-Film Multijunction Thermal Converters

    Energy Technology Data Exchange (ETDEWEB)

    WUNSCH,THOMAS F.; KINARD,J.R.; MANGINELL,RONALD P.; SOLOMON JR.,OTIS M.; LIPE,T.E.; JUNGLING,KENNETH CORNEAL

    2000-12-08

    Advanced thin film processing and packaging technologies are employed in the fabrication of new planar thin-film multifunction thermal converters. The processing, packaging, and design features build on experience gained from prior NIST demonstrations of thin-film converters and are optimized for improved sensitivity, bandwidth, manufacturability, and reliability.

  7. Development of automated welding process for field fabrication of thick walled pressure vessels

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, U A

    1981-01-01

    Research on automatic welding processes for the fabrication of thick-walled pressure vessels continued. A literature review on the subject was completed. A laboratory study of criteria for judging acceptable root parameters continued. Equipment for a demonstration facility to test the components and processes of the automated welding system has been specified and is being obtained. (LCL)

  8. Standard format and content of license applications for plutonium processing and fuel fabrication plants

    International Nuclear Information System (INIS)

    1976-01-01

    The standard format suggested for use in applications for licenses to possess and use special nuclear materials in Pu processing and fuel fabrication plants is presented. It covers general description of the plant, summary safety assessment, site characteristics, principal design criteria, plant design, process systems, waste confinement and management, radiation protection, accident safety analysis, conduct of operations, operating controls and limits, and quality assurance

  9. Investigation of small scale sphere-pac fuel fabrication plant with external gelation process

    International Nuclear Information System (INIS)

    Maekawa, Kazuhiko; Yoshimura, Tadahiro; Kikuchi, Toshiaki; Hoshino, Yasushi; Munekata, Hideki; Shimizu, Makoto

    2005-02-01

    In feasibility studies on commercialized FBR cycle system, comprehensive system investigation and properties evaluation for candidate FBR cycle systems have been implemented through view point of safety, economics, environmental burden reduction, non-proliferation resistivity, etc. As part of these studies, an investigation of small scale sphere-pac fuel fabrication plant with external gelation process was conducted. Until last fiscal year, equipment layout in cells and overall layout design of the 200t-HM/y scale fuel fabrication plant were conducted as well as schematical design studies on main equipments in gelation and reagent recovery processes of the plant. System property data concerning economics and environmental burden reduction of fuel fabrication plant was also acquired. In this fiscal year, the processes from vibropacking to fuel assemblies storage were added to the investigation range, and a conceptual design of whole fuel fabrication plant was studied as well as deepening the design study on main equipments. The conceptual design study was mainly conducted for small 50t-HM/y scale plant and a revising investigation was done for 200t-HM/y scale plant. Taking the planed comparative evaluation with pellet fuel fabrication system into account, design of equipments which should be equivalent with pellet system, especially in post-vibropacking processes, were standardized in each system. Based on these design studies, system properties data concerning economics and environmental burden reduction of the plant was also acquired. In comparison with existing design, the cell height was lowered on condition that plug type pneumatic system was adopted and fuel fabrication building was downsized by applying rationalized layout design of pellet system to post-vibropacking processes. Reduction of reagent usage at gelation process and rationalization of sintering and O/M controlling processes etc., are foremost tasks. (author)

  10. Laser Control of Self-Organization Process in Microscopic Region and Fabrication of Fine Microporous Structure

    Directory of Open Access Journals (Sweden)

    Yukimasa Matsumura

    2012-01-01

    Full Text Available We present a controlling technique of microporous structure by laser irradiation during self-organization process. Self-organization process is fabrication method of microstructure. Polymer solution was dropped on the substrate at high humid condition. Water in air appears dropping air temperature below the dew point. The honeycomb structure with regularly aligned pores on the film was fabricated by attaching water droplets onto the solution surface. We demonstrate that it was possible to prevent forming pores at the region of laser irradiation and flat surface was fabricated. We also demonstrated that a combination structure with two pore sizes and flat surface was produced by a single laser-pulse irradiation. Our method is a unique microfabrication processing technique that combines the advantages of bottom-up and top-down techniques. This method is a promising technique that can be applied to produce for photonic crystals, biological cell culturing, surface science and electronics fields, and so forth.

  11. Porous Gold Films Fabricated by Wet-Chemistry Processes

    Directory of Open Access Journals (Sweden)

    Aymeric Pastre

    2016-01-01

    Full Text Available Porous gold films presented in this paper are formed by combining gold electroless deposition and polystyrene beads templating methods. This original approach allows the formation of conductive films (2 × 106 (Ω·cm−1 with tailored and interconnected porosity. The porous gold film was deposited up to 1.2 μm on the silicon substrate without delamination. An original zirconia gel matrix containing gold nanoparticles deposited on the substrate acts both as an adhesion layer through the creation of covalent bonds and as a seed layer for the metallic gold film growth. Dip-coating parameters and gold electroless deposition kinetics have been optimized in order to create a three-dimensional network of 20 nm wide pores separated by 20 nm thick continuous gold layers. The resulting porous gold films were characterized by GIXRD, SEM, krypton adsorption-desorption, and 4-point probes method. The process is adaptable to different pore sizes and based on wet-chemistry. Consequently, the porous gold films presented in this paper can be used in a wide range of applications such as sensing, catalysis, optics, or electronics.

  12. Wear Process Analysis of the Polytetrafluoroethylene/Kevlar Twill Fabric Based on the Components’ Distribution Characteristics

    Directory of Open Access Journals (Sweden)

    Gu Dapeng

    2017-12-01

    Full Text Available Polytetrafluoroethylene (PTFE/Kevlar fabric or fabric composites with excellent tribological properties have been considered as important materials used in bearings and bushing, for years. The components’ (PTFE, Kevlar, and the gap between PTFE and Kevlar distribution of the PTFE/Kevlar fabric is uneven due to the textile structure controlling the wear process and behavior. The components’ area ratio on the worn surface varying with the wear depth was analyzed not only by the wear experiment, but also by the theoretical calculations with our previous wear geometry model. The wear process and behavior of the PTFE/Kevlar twill fabric were investigated under dry sliding conditions against AISI 1045 steel by using a ring-on-plate tribometer. The morphologies of the worn surface were observed by the confocal laser scanning microscopy (CLSM. The wear process of the PTFE/Kevlar twill fabric was divided into five layers according to the distribution characteristics of Kevlar. It showed that the friction coefficients and wear rates changed with the wear depth, the order of the antiwear performance of the previous three layers was Layer III>Layer II>Layer I due to the area ratio variation of PTFE and Kevlar with the wear depth.

  13. Modeling of an improved chemical vapor infiltration process for ceramic composites fabrication

    International Nuclear Information System (INIS)

    Tai, N.H.; Chou, T.W.

    1990-01-01

    A quasi-steady-state approach is applied to model the pressure-driven, temperature-gradient chemical vapor infiltration (improved CVI process) for ceramic matrix composites fabrication. The deposited matrix in this study is SiC which is converted from the thermal decomposition of methyltrichlorosilane gas under excess hydrogen. A three-dimensional unit cell is adopted to simulate the spatial arrangements of reinforcements in discontinuous fiber mats and three-dimensionally woven fabrics. The objectives of this paper are to predict the temperature and density distributions in a fibrous preform during processing, the advancement of the solidified front, the total fabrication period, and the vapor inlet pressure variation for maintaining a constant flow rate

  14. Fabrication of Vacuum-Sealed Capacitive Micromachined Ultrasonic Transducer Arrays Using Glass Reflow Process

    Directory of Open Access Journals (Sweden)

    Nguyen Van Toan

    2016-04-01

    Full Text Available This paper presents a process for the fabrication of vacuum-sealed capacitive micromachined ultrasonic transducer (CMUT arrays using glass reflow and anodic bonding techniques. Silicon through-wafer interconnects have been investigated by the glass reflow process. Then, the patterned silicon-glass reflow wafer is anodically bonded to an SOI (silicon-on-insulator wafer for the fabrication of CMUT devices. The CMUT 5 × 5 array has been successfully fabricated. The resonant frequency of the CMUT array with a one-cell radius of 100 µm and sensing gap of 3.2 µm (distance between top and bottom electrodes is observed at 2.84 MHz. The Q factor is approximately 1300 at pressure of 0.01 Pa.

  15. Application of foams to the processing of fabrics. Final report, October 1, 1977-September 30, 1979

    Energy Technology Data Exchange (ETDEWEB)

    Duke, M.W.

    1979-12-01

    In mill trials, a range of foam fabric finishes including softeners, hand builders, and durable-press and shrink-resistant types were applied to cotton sheeting, corduroy, and polyester/cellulosic blends, etc. In all cases, substantial energy savings were realized. A number of companies are currently using foam fabric finishing as a commercial production process. Additionally, the pilot range has been used to demonstrate foam fabric finishing to over twenty companies. The range has been used to demonstrate the foam acid dyeing of nylon carpets to several companies in this specialized area of textile processing. Active work still continues with these companies since the foam dyeing of carpets involves only about 1/5 the water used in the normal continuous dyeing of carpets. Energy conservation is realized both from reduced steam consumption in steaming colors and less heat used for drying.

  16. Literature on fabrication of tungsten for application in pyrochemical processing of spent nuclear fuels

    International Nuclear Information System (INIS)

    Edstrom, C.M.; Phillips, A.G.; Johnson, L.D.; Corle, R.R.

    1980-01-01

    The pyrochemical processing of nuclear fuels requires crucibles, stirrers, and transfer tubing that will withstand the temperature and the chemical attack from molten salts and metals used in the process. This report summarizes the literature that pertains to fabrication (joining, chemical vapor deposition, plasma spraying, forming, and spinning) is the main theme. This report also summarizes a sampling of literature on molbdenum and the work previously performed at Argonne National Laboratory on other container materials used for pyrochemical processing of spent nuclear fuels

  17. Additive advantage in characteristics of MIMCAPs on flexible silicon (100) fabric with release-first process

    KAUST Repository

    Ghoneim, Mohamed T.

    2013-11-20

    We report the inherent increase in capacitance per unit planar area of state-of-the art high-κ integrated metal/insulator/metal capacitors (MIMCAPs) fabricated on flexible silicon fabric with release-first process. We methodically study and show that our approach to transform bulk silicon (100) into a flexible fabric adds an inherent advantage of enabling higher integration density dynamic random access memory (DRAM) on the same chip area. Our approach is to release an ultra-thin silicon (100) fabric (25 μm thick) from the bulk silicon wafer, then build MIMCAPs using sputtered aluminium electrodes and successive atomic layer depositions (ALD) without break-ing the vacuum of a high-κ aluminium oxide sandwiched between two tantalum nitride layers. This result shows that we can obtain flexible electronics on silicon without sacrificing the high density integration aspects and also utilize the non-planar geometry associated with fabrication process to obtain a higher integration density compared to bulk silicon integration due to an increased normalized capacitance per unit planar area. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Effect of the preform fabrication process on the properties of all-silica optical fibres

    Science.gov (United States)

    Grishchenko, A. B.

    2017-12-01

    In this paper, we present a detailed comparison of technical capabilities of processes for the fabrication of all-silica optical fibre preforms with the use of an atmospheric pressure radio frequency plasma (POVD process) and low-pressure microwave plasma (PCVD process) and analyse the origin of the difference in optical properties between fibres produced by these methods. It is shown that the higher temperature of the core material and the higher oxygen partial pressure in preform fabrication by the POVD process lead to an increase in optical losses in the visible and UV spectral regions in the silica fibres with low hydroxyl (OH) content and a decrease in the solarisation resistance of the fibres with high OH content, i.e. to a more rapid increase in background losses in response to UV irradiation. No such drawbacks are detected in the case of the growth of reflective layers by the PCVD process.

  19. Mutual diffusion process for continuous fabrication of graded-index plastic rod lenses

    Science.gov (United States)

    Uozu, Yoshihiro; Horie, Kazuyuki

    2003-11-01

    We propose a new process for fabrication of plastic rod lenses based on the traditional method of fiber extrusion. The process consists of the following steps: multilayer conjugate extrusion, monomer diffusion between adjacent layers, and photopolymerization of an uncured strand fiber. We call this process a mutual diffusion process for continuous plastic rod lens fabrication. Characteristics of this process are as follows: fast production speed (~100 cm/min), precision control of refractive-index distribution, high angular aperture, and long-term reliability. The optical resolution of the rod-lens array is 300 dpi, which is high enough for application to G3 facsimiles with transmission time of less than 1 min and monochromatic scanners.

  20. Solar Energy: Materials, Materials Handling, and Fabrication Processes: Student Material. First Edition.

    Science.gov (United States)

    Bolin, William Everet; Orsak, Charles G., Jr.

    Designed for student use in "Materials, Materials Handling, and Fabrication Processes," one of 11 courses in a 2-year associate degree program in solar technology, this manual provides readings, exercises, worksheets, bibliographies, and illustrations for 13 course modules. The manual, which corresponds to an instructor guide for the…

  1. Shape distortions in fabric reinforced composite products due to processing induced fibre reorientation

    NARCIS (Netherlands)

    Lamers, E.A.D.

    2004-01-01

    Woven fabric reinforced composite materials are typically applied in plate or shell structures, such as ribs, stiffeners and skins. Products of these types can be produced with several production processes. A few examples are diaphragm forming, matched metal die forming and rubber press forming.

  2. All polymer, injection molded nanoslits, fabricated through two-level UV-LIGA processes

    DEFF Research Database (Denmark)

    Østergaard, Peter Friis; Matteucci, Marco; Marie, Rodolphe

    2012-01-01

    in the micro- and nanoregime is required. To obtain this, injection molding is included in the research process for making several chips (100-1000) with the same layout. The time it takes for the individual chip to be fabricated in this way is much shorter than with conventional cleanroom methods...

  3. Towards Polarization Diversity on the SOI Platform With Simple Fabrication Process

    DEFF Research Database (Denmark)

    Ding, Yunhong; Liu, Liu; Peucheret, Christophe

    2011-01-01

    We present a polarization diversity circuit built on the silicon-on-insulator (SOI) platform, which can be fabricated by a simple process. The polarization diversity is based on two identical air-clad asymmetrical directional couplers, which simultaneously play the roles of polarization splitter...

  4. Fabrication of long REBCO coated conductors by PLD process in China

    Energy Technology Data Exchange (ETDEWEB)

    Li, Yijie, E-mail: yjli@sjtu.edu.cn [Key Laboratory of Artificial Structure and Quantum Control, Ministry of Education, Department of Physics and Astronomy, Shanghai Jiao Tong University, 800 Dong Chuan Road, Shanghai 20040 (China); Shanghai Superconductor Technology Corporation, Ltd, 28 Jiang Chuan Road, Shanghai 200240 (China); Liu, Linfei; Wu, Xiang [Key Laboratory of Artificial Structure and Quantum Control, Ministry of Education, Department of Physics and Astronomy, Shanghai Jiao Tong University, 800 Dong Chuan Road, Shanghai 20040 (China)

    2015-11-15

    Highlights: • SJTU fabricated 100 m long class CC tapes with over 300 A/cm on RABiTS tapes in 2011. • 100 m long CC tapes with 500 A/cm have been routinely fabricated on IBAD-MgO tapes. • The process optimization for kilometer long coated conductor tapes is underway. - Abstract: In China, the First National Key Project on CC Program started in 2009, which was focused on developing hundred meter long class CC tapes based on PLD/RABiTS processes. In this project, SJTU mainly worked on all of functional layer deposition process development. Northwest Institute for Non-ferrous Metal Research worked on RABiTS tape fabrication. At the end of the project in 2011, SJTU successfully fabricated hundred meter long CC tapes with over 300 A/cm (at 77 K, self field) on RABiTS tapes. To develop high performance CC tapes by PLD/IBAD-MgO processes, a pilot CC fabrication line was set up at Shanghai Superconductor Technology Corporation, Ltd. in 2013. High quality long REBCO coated conductors have been successfully fabricated on flexible polycrystalline metal tapes by PLD plus magnetron sputter and IBAD processes. Under optimized conditions, the IBAD-MgO layers showed pure (0 0 1) orientation and excellent in-plane texture. The in-plane phi-scan rocking curve is 4–6 degrees. AFM observation showed MgO layer had very smooth surface. The RMS is less 1 nm. On the textured MgO layer, sputter deposited single cerium oxide cap-layer showed pure (0 0 1) orientation and excellent in-plane texture of 4–6 degree. Reel-to-reel PLD process with high deposition rate was already scaled up to 100 m/h tape speed. Hundred meters long coated conductor tapes with over 500 A/cm performance have been routinely fabricated. And now, the process optimization for kilometer long coated conductor tapes is underway.

  5. Structures and Techniques For Implementing and Packaging Complex, Large Scale Microelectromechanical Systems Using Foundry Fabrication Processes.

    Science.gov (United States)

    1996-06-01

    torsion suspensions. Perhaps the best example of a torsional actuator is the Texas Instruments Digital Micromirror Device™ (DMD™). Figure 3-5...Array Design 5-57 5.2.2.3.3 Cover Plate Design 5-60 5.2.2.3.4 Fabrication Results 5-62 in Table of Contents (Cont.) Page 5.2.2.3.5 Micromirror and...electrostatic micromirror 2-33 Figure 2-20. Photograph of test die fabricated in the MUMPS4 process 2-35 Figure 2-21. Etch gauge from MUMPS3 2-37

  6. Comparison of Jacket Production Processes Designed by Fabric Materials and Leather

    Directory of Open Access Journals (Sweden)

    Emine Utkun

    2011-02-01

    Full Text Available Leather and leather products industry has shown a significant improvement in export area, as a result of intensive shuttle trades and demand that comes from crumbling Eastern Bloc countries in 1990's. This development has caused capacity increasing and thus makes large investments in this sector. Leather garment industry differs from woven or fabrics industry at various points. Differantation seems in raw materials features such as size, thickness, biological, chemical or physical homogenity. Due to the natural structure, leather shows different attributes in different regions. This study examines the diversity of production processes of leather and fabric designed jacket.

  7. Material control in nuclear fuel fabrication facilities. Part I. Fuel descriptions and fabrication processes, P.O. 1236909 Final report

    International Nuclear Information System (INIS)

    Borgonovi, G.M.; McCartin, T.J.; Miller, C.L.

    1978-12-01

    The report presents information on foreign nuclear fuel fabrication facilities. Fuel descriptions and fuel fabrication information for three basic reactor types are presented: The information presented for LWRs assumes that Pu--U Mixed Oxide Fuel (MOX) will be used as fuel

  8. Material control in nuclear fuel fabrication facilities. Part I. Fuel descriptions and fabrication processes, P. O. 1236909 Final report

    Energy Technology Data Exchange (ETDEWEB)

    Borgonovi, G.M.; McCartin, T.J.; Miller, C.L.

    1978-12-01

    The report presents information on foreign nuclear fuel fabrication facilities. Fuel descriptions and fuel fabrication information for three basic reactor types are presented: The information presented for LWRs assumes that Pu--U Mixed Oxide Fuel (MOX) will be used as fuel.

  9. Oxide-confined VCSELs fabricated with a simple self-aligned process flow

    Science.gov (United States)

    Marigo-Lombart, L.; Calvez, S.; Arnoult, A.; Thienpont, H.; Panajotov, K.; Almuneau, G.

    2017-12-01

    We propose a simplified and easier fabrication process flow for the manufacturing of AlO x -confined vertical-cavity surface-emitting lasers (VCSELs) based on combining the oxidation step with a self-aligned process, allowing the mesa etching and two successive lift-off steps based on a single lithography step. The electro-optical confinement achieved by standard lateral oxidation enables a low threshold and a single mode behavior for the VCSEL. This simplified process can largely improve VCSEL manufacturing by reducing the processing time and costs compared to the standard VCSEL process.

  10. Stereogeneous construction – fabric-formed concrete as material and process

    DEFF Research Database (Denmark)

    Manelius, Anne-Mette

    2012-01-01

    På engelsk: This paper contributes to studies of architectural potentials of fabric formwork for concrete by seeking to establish a theoretical concept that evaluates qualities of materials and principles of construction as well as aspects of the expression of concrete construction. Through...... for concrete means, however, that a discussion of the qualities of formwork principles and construc¬tion procedures have yet to be combined with the expression of construction to discuss the unseen potentials for making architectural space and place in architectural concrete constructions. The paper discusses....... The word describes concrete as material and process. Fabric Formwork is the pivotal formwork-tectonic topic of investigation in the experimental and analytical parts of the thesis work on which this paper is based. The youth of the architectural application of construction methods for fabric formwork...

  11. A miniature rigid/flex salinity measurement device fabricated using printed circuit processing techniques

    International Nuclear Information System (INIS)

    Broadbent, H A; Ketterl, T P; Reid, C S

    2010-01-01

    The design, fabrication and initial performance of a single substrate, miniature, low-cost conductivity, temperature, depth (CTD) sensor board with interconnects are presented. In combination these sensors measure ocean salinity. The miniature CTD device board was designed and fabricated as the main component of a 50 mm × 25 mm × 25 mm animal-attached biologger. The board was fabricated using printed circuit processes and consists of two distinct regions on a continuous single liquid crystal polymer substrate: an 18 mm × 28 mm rigid multi-metal sensor section and a 72 mm long flexible interconnect section. The 95% confidence intervals for the conductivity, temperature and pressure sensors were demonstrated to be ±0.083 mS cm −1 , 0.01 °C, and ±0.135 dbar, respectively.

  12. Robotic-Controlled, Autonomous Friction Stir Welding Processes for In-Situ Fabrication, Maintenance, and Repair

    Science.gov (United States)

    Zhou, W.

    NASA s new vision of human and robotic missions to the Moon Mars and beyond will demand large and permanent infrastructures on the Moon and other planets including power plants communication towers human and biomass habitats launch and landing facilities fabrication and repair workshops and research facilities so that material utilization and product development can be carried out and subsisted in-situ The conventional approach of transporting pre-constructed fabricated structures from earth to the Moon planets will no longer be feasible due to limited lifting capacity and extremely high transportation costs associated with long duration space travel To minimize transport of pre-made large structures between earth and the Moon planets minimize crew time for the fabrication and assembly of infrastructures on the Moon planets and to assure crew safety and maintain quality during the operation there is a strong need for robotic capabilities for in-situ fabrication maintenance and repair Clearly development of innovative autonomous in-situ fabrication maintenance and repair technologies is crucial to the success of both NASA s unmanned preparation missions and manned exploration missions In-space material joining is not new to NASA Many lessons were learned from NASA s International Space Welding Experiment which employed the Electron Beam Welding process for space welding experiments Significant safety concerns related to high-energy beams arcing spatter elecromagnetic fields and molten particles were

  13. A simplified fabrication process of Fresnel zone plates with controlling proximity effect correction.

    Science.gov (United States)

    Jeon, Sang Chul; Kim, Deuk Su; Kim, Ki Nam; Kim, Kyung Min; Seo, Chang Ho; Yoo, Jung Jae; Lee, Dong Kyu

    2011-01-01

    Fresnel zone plates (FZPs) for soft X-ray microscopy with an energy range of 284 eV to 540 eV are designed and fabricated in a simple method. An adequate aspect ratio of the resist mold for electroplating was obtained by the proximity effect correction technology for an incident electron beam on a single thick layer resist. Without additional complicated reactive ion etching, a sufficient electro plating mold for nickel structures was fabricated. The overall fabrication procedures which involve a mix-and-match overlay technique for electron beam lithography and an optic exposure system that centers the membrane on the nanostructures, and hybrid silicon etching technology in junction with deep anisotropy and a KOH wet method in order to release the backside Si substrates of the Si3N4 membranes with no deformation of FZPs are introduced. High quality nanostructures with minimum outermost zone widths of 50 nm and diameters of 120 microm were fabricated with simplified fabrication process and with cost-effective.

  14. A Scalable Fabrication Process for Liquid Crystal Based Uncooled Thermal Imagers

    Science.gov (United States)

    2016-02-12

    compatible with CMOS microfabrication. Figure 5 shows photographs of the jig specially fabricated for this process. This was an in-situ, wafer-scale...dimension of several nanometers in height and width on the surface. A 200-mm wafer was held in place on a lapping jig and was submerged in...Alignment lapping jig for mechanical diamond lapping process. a) 200-mm wafer held in jig , submerged in DI. b) 500-nm grit diamond lapping film mounted to

  15. A process for the fabrication of ceramic fibre reinforced titanium aluminide

    OpenAIRE

    Horsfall, Ian; Cundy, S. J.

    1992-01-01

    This paper describes initial work on a novel process for the production of titanium aluminide matrix composites reinforced with short alumina fibers. The processing route involves an adaption of existing metal matrix composite (MMC) fabrication technology used to produce hybrid particulate/short fiber composites. A preform is produced which contains alumina fibers and titanium metal powder with a fiber content of around 10% by volume and approximately 50% porosity. This preform is then infilt...

  16. Investigation of heat treatment conditions of structural material for blanket fabrication process

    International Nuclear Information System (INIS)

    Hirose, Takanori; Suzuki, Satoshi; Akiba, Masato; Shiba, Kiyoyuki; Sawai, Tomotsugu; Jitsukawa, Shiro

    2004-01-01

    This paper presents recent results of thermal hysteresis effects on ceramic breeder blanket structural material. Reduced activation ferritic/martensitic (RAF) steel is the leading candidates for the first wall structural materials of breeding blankets. RAF steel demonstrates superior resistance to high dose neutron irradiation, because the steel has tempered martensite structure which contains the number of sink site for radiation defects. This microstructure obtained by two-step heat treatment, first is normalizing at temperature above 1200 K and the second is tempering at temperature below 1100 K. Recent study revealed the thermal hysteresis has significant impacts on the post-irradiation mechanical properties. The breeding blanket has complicated structure, which consists of tungsten armor and thin first wall with cooling pipe. The blanket fabrication requires some high temperature joining processes. Especially hot isostatic pressing (HIP) is examined as a near-net-shape fabrication process for this structure. The process consists of heating above 1300 K and isostatic pressing at the pressure above 150 MPa followed by tempering. Moreover ceramics pebbles are packed into blanket module and the module is to be seamed by welding followed by post weld heat treatment in the final assemble process. Therefore the final microstructural features of RAFs strongly depend on the blanket fabrication process. The objective of this work is to evaluate the effects of thermal hysteresis corresponding to blanket fabrication process on RAFs microstructure in order to establish appropriate blanket fabrication process. Japanese RAFs F82H (Fe-0.1C-8Cr-2W-0.2V-0.05Ta) was investigated by metallurgical method after isochronal heat treatment up to 1473 K simulating high temperature bonding process. Although F82H showed significant grain growth after conventional solid HIP conditions (1313 K x 2 hr.), this coarse grained microstructure was refined by the post HIP normalizing at

  17. Silicon solar cell process development, fabrication and analysis. Third quarterly report, January 1-March 31, 1979

    Energy Technology Data Exchange (ETDEWEB)

    Yoo, H.I.; Iles, P.A.; Tanner, D.P.

    1979-01-01

    The objective of this program is to investigate, develop, and utilize technologies appropriate and necessary for improving the efficiency of solar cells made from various unconventional silicon sheets. Work has progressed in fabrication and characterization of solar cells from cast silicon by heat exchanger method (Crystal Systems), EFG (RH) ribbon (Mobil Tyco) and silicon on ceramic (Honeywell). Silicon blanks (2 x 2 cm) were prepared from the HEM cast silicon and EFG ribbon, using conventional slicing techniques, and fabricated using a standard process typical of those used currently in the silicon solar cell industry. Also a back surface field (BSF) process and other process modifications were included in processing additional slices. Relatively large area (about 15 cm/sup 2/) solar cells were fabricated from silicon on ceramic substrates using a standard process that can be easily adapted to these substrates. Evaluation of the SOC solar cells has not been completed in this reporting period. The performance parameters measured included open circuit voltage, short circuit current, curve fill factor, and conversion efficiency (all taken under AMO illumination). Also measured for typical cells were spectral response, dark I-V characteristics, minority carrier diffusion length, and photoresponse by fine light scanning. The results were compared to the properties of cells made from the conventional single crystalline Czochralski silicon with an emphasis on statistical evaluation. Limited efforts were made to identify defects which will influence solar cell performance.

  18. THE DYEING PROCESS OF KNITTED FABRICS AT DIFFERENT TEMPERATURES USING ULTRASOUND

    Directory of Open Access Journals (Sweden)

    MITIC Jelena

    2014-05-01

    Full Text Available The dyeing of knitted fabrics made from 100 % cellulose using on-line procedure vinyl sulfonic reactive dye, with or without ultrasound energy, is carried out in this paper. The impact of temperature has been observed. The dye exhaustion is monitored using the method of absorption spectrophotometry, and the quality control of the coloration is monitored using color measurements. The acting of ultrasound on coloration consistency, as well as on some mechanical characteristics has also been examined. All examples of the ultrasound dyeing process show greater dye exhaustion in comparison to the conventional procedure. In addition, all the samples, which have been dyed with the ultrasound energy at 40°C, are significantly darker and have deeper color in comparison with the referent sample. The temperature has a great influence on kinetic energy of the dye molecules, and therefore on the diffusion processes in the dyeing system. The exhaustion chart indicates that when the temperature is lower the exhaustion degree drops. However, all the samples dyed with the ultrasound energy have bigger exhaustion. Besides that, ultrasound energy contributes to warming up the processing environment, so the additional warm up with the electricity is unnecessary, unlike the conventional way of dyeing. Since the reactive dyes chemically connect themselves with the cellulose substrate and in that way form covalent connection, the dyed fabrics have good washing consistency. Analysis results indicate that the consistencies are identical regardless the applied dyeing procedure. In other words, the dyeing method using the ultrasound energy produces the dyed fabric of the same quality. After analyzing the results of breaking force and elongation at break of knitted fabrics, it is noticeable that there is no degradation of previously mentioned knitted fabrics features (horizontally and vertically during the ultrasound wave’s activity.

  19. Computer electric design of synchronous generators; Diseno electrico de generadores sincronos por computadora

    Energy Technology Data Exchange (ETDEWEB)

    Patlan Frausto, Jose O.; Acosta Aradillas, Juan [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1986-12-31

    In this article are presented, in a conceptual manner the main elements that participate in the electric design of synchronous generators. Also, other options are presented for computers utilization as a design support. Afterwards, a computer program developed by the Instituto de Investigaciones Electricas (IIE) for the electric design of projecting poles generators is presented, oriented towards obtaining their electro-magnetic dimensioning. Finally, with the purpose of validating this program, the results obtained in a specific case, are presented. [Espanol] En este articulo se presentan, de manera conceptual, los principales elementos que participan en el proceso de diseno electrico de generadores sincronos. Tambien se plantean otras opciones para utilizar las computadoras como apoyo de diseno. Posteriormente, se describe un programa de computo desarrollado en el Instituto de Investigaciones Electricas (IIE) para el diseno electrico de generadores de polos salientes, orientado a obtener su dimensionamiento electromagnetico. Por ultimo, con el proposito de validar este programa, se presentan los resultados obtenidos en un caso particular.

  20. Impact of process temperature on GaSb metal-oxide-semiconductor interface properties fabricated by ex-situ process

    Energy Technology Data Exchange (ETDEWEB)

    Yokoyama, Masafumi, E-mail: yokoyama@mosfet.t.u-tokyo.ac.jp; Takenaka, Mitsuru; Takagi, Shinichi [Department of Electrical Engineering and Information Systems, The University of Tokyo, Yayoi 2-11-16, Bunkyo, Tokyo 113-0032 (Japan); JST-CREST, Yayoi 2-11-16, Bunkyo, Tokyo 113-0032 (Japan); Asakura, Yuji [Department of Electrical Engineering and Information Systems, The University of Tokyo, Yayoi 2-11-16, Bunkyo, Tokyo 113-0032 (Japan); Yokoyama, Haruki [NTT Photonics Laboratories, NTT Corporation, Atsugi 243-0198 (Japan)

    2014-06-30

    We have studied the impact of process temperature on interface properties of GaSb metal-oxide-semiconductor (MOS) structures fabricated by an ex-situ atomic-layer-deposition (ALD) process. We have found that the ALD temperature strongly affects the Al{sub 2}O{sub 3}/GaSb MOS interface properties. The Al{sub 2}O{sub 3}/GaSb MOS interfaces fabricated at the low ALD temperature of 150 °C have the minimum interface-trap density (D{sub it}) of ∼4.5 × 10{sup 13 }cm{sup −2} eV{sup −1}. We have also found that the post-metalization annealing at temperature higher than 200 °C degrades the Al{sub 2}O{sub 3}/GaSb MOS interface properties. The low-temperature process is preferable in fabricating GaSb MOS interfaces in the ex-situ ALD process to avoid the high-temperature-induced degradations.

  1. Statistical methods to assess and control processes and products during nuclear fuel fabrication

    International Nuclear Information System (INIS)

    Weidinger, H.

    1999-01-01

    Very good statistical tools and techniques are available today to access the quality and the reliability of fabrication process as the original sources for a good and reliable quality of the fabricated processes. Quality control charts of different types play a key role and the high capability of modern electronic data acquisition technologies proved, at least potentially, a high efficiency in the more or less online application of these methods. These techniques focus mainly on stability and the reliability of the fabrication process. In addition, relatively simple statistical tolls are available to access the capability of fabrication process, assuming they are stable, to fulfill the product specifications. All these techniques can only result in as good a product as the product design is able to describe the product requirements necessary for good performance. Therefore it is essential that product design is strictly and closely performance oriented. However, performance orientation is only successful through an open and effective cooperation with the customer who uses or applies those products. During the last one to two decades in the west, a multi-vendor strategy has been developed by the utility, sometimes leading to three different fuel vendors for one reactor core. This development resulted in better economic conditions for the user but did not necessarily increase an open attitude with the vendor toward the using utility. The responsibility of the utility increased considerably to ensure an adequate quality of the fuel they received. As a matter of fact, sometimes the utilities had to pay a high price because of unexpected performance problems. Thus the utilities are now learning that they need to increase their knowledge and experience in the area of nuclear fuel quality management and technology. This process started some time ago in the west. However, it now also reaches the utilities in the eastern countries. (author)

  2. A Novel Continuous Extrusion Process to Fabricate Wedge-Shaped Light Guide Plates

    Directory of Open Access Journals (Sweden)

    Wen-Tse Hsiao

    2013-01-01

    Full Text Available Backlight modules are key components in thin-film transistor liquid crystal displays (TFT-LCD. Among the components of a backlight module, the light guide plate (LGP plays the most important role controlling the light projected to the eyes of users. A wedge-shaped LGP, with its asymmetrical structure, is usually fabricated by an injection proces, but the fabrication time of this process is long. This study proposes a continuous extrusion process to fabricate wedge-shaped LGPs. This continuous process has advantages for mass production. Besides a T-die and rollers, this system also has an in situ monitor of the melt-bank that forms during the extrusion process, helping control the plate thickness. Results show that the melt bank has a close relationship with the plate thickness. The temperature of the bottom heater and roller was adjusted to reduce the surface deformation of the wedge-shaped plate. This continuous extrusion system can successfully manufacture wedge-shaped LGPs for mass production.

  3. Materials Selection And Fabrication Practices For Food Processing Equipment Manufacturers In Uganda

    Directory of Open Access Journals (Sweden)

    John Baptist Kirabira

    2017-08-01

    Full Text Available The food processing industry is one of the fast-growing sub-sectors in Uganda. The industry which is majorly composed of medium and small scale firms depends on the locally developed food processing equipment. Due to lack of effective materials selection practices employed by the equipment manufacturers the materials normally selected for most designs are not the most appropriate ones hence compromising the quality of the equipment produced. This has not only led to poor quality food products due to contamination but could also turn out health hazardous to the consumers of the food products. This study involved the assessment of the current materials selection and fabrication procedures used by the food processing equipment manufacturers with a view of devising best practices that can be used to improve the quality of the food products processed by the locally fabricated equipment. Results of the study show that designers experience biasness and desire to minimize cost compromise the materials selection procedure. In addition to failing to choose the best material for a given application most equipment manufacturers are commonly fabricating equipment with inadequate surface finish and improper weldments. This hinders the equipments ability to meet food hygiene standards.

  4. Investigation of a thermoplastic-powder metallurgy process for the fabrication of porous niobium rods

    International Nuclear Information System (INIS)

    Nordin, D.R.

    1978-06-01

    The feasibility of using a thermoplastic-powder metallurgy technique for the fabrication of porous niobium rods was investigated. Some early problems were overcome to successfully extrude the polymer coated niobium powder into long lengths. The effects of certain process variables were investigated. Residual porosity and extrusion pressure were found to be regulated by the polymer fraction. The procedures for taking the extruded polystyrene--niobium rods through the heat treatments to the final, tin infiltrated stage are explained

  5. Characterization of high-purity niobium structures fabricated using the electron beam melting process

    Science.gov (United States)

    Terrazas Najera, Cesar Adrian

    Additive Manufacturing (AM) refers to the varied set of technologies utilized for the fabrication of complex 3D components from digital data in a layer-by-layer fashion. The use of these technologies promises to revolutionize the manufacturing industry. The electron beam melting (EBM) process has been utilized for the fabrication of fully dense near-net-shape components from various metallic materials. This process, catalogued as a powder bed fusion technology, consists of the deposition of thin layers (50 - 120microm) of metallic powder particles which are fused by the use of a high energy electron beam and has been commercialized by Swedish company Arcam AB. Superconducting radio frequency (SRF) cavities are key components that are used in linear accelerators and other light sources for studies of elemental physics. Currently, cavity fabrication is done by employing different forming processes including deep-drawing and spinning. In both of the latter techniques, a feedstock high-purity niobium sheet with a thickness ranging from 3-4 mm is mechanically deformed and shaped into the desired geometry. In this manner, half cavities are formed that are later joined by electron beam welding (EBW). The welding step causes variability in the shape of the cavity and can also introduce impurities at the surface of the weld interface. The processing route and the purity of niobium are also of utmost importance since the presence of impurities such as inclusions or defects can be detrimental for the SRF properties of cavities. The focus of this research was the use of the EBM process in the manufacture of high purity niobium parts with potential SRF applications. Reactor grade niobium was plasma atomized and used as the precursor material for fabrication using EBM. An Arcam A2 system was utilized for the fabrication. The system had all internal components of the fabrication chamber replaced and was cleaned to prevent contamination of niobium powder. A mini-vat, developed at

  6. Improvement of the process for immobilization of silver nanoparticles onto cotton and peco fabrics to prepare antibacterial fabrics

    International Nuclear Information System (INIS)

    Truong Thi Hanh; Nguyen Thi Thu; Dang Van Phu; Le Anh Quoc; Nguyen Quoc Hien

    2015-01-01

    Silver nanoparticles (AgNPs) with diameter about 11.6 ± 0.7 nm in chitosan solution were synthesized by γ-irradiation at the dose of 17.6 kGy, and then immobilized onto fabrics. The Ag-NPs contents onto cotton and peco fabrics were about 1700 and 140 mg/kg for the initial AgNPs concentrations of 1000 and 100 ppm, respectively. The AgNPs colloidal solution was characterized by UV-Vis spectroscopy and TEM image. The AgNPs size has been estimated by using Debye-Scherrer formula from X ray diffraction pattern. The presence of AgNPs on fabrics was confirmed from scanning electron microscopy (SEM) images. The antibacterial activity of AgNPs cotton and peco fabrics after 60 washings against Staphylococcus aureus and Klebsiella pneumonia was found to be > 99.40%. Effects of AgNPs on multidrug-resistant pathogens from the clinical specimens were also tested. In addition, the AgNPs fabrics were innoxious to the skin (k=0) by skin-irritation testing to animal (rabbit). (author)

  7. Development of a Multi-User Polyimide-MEMS Fabrication Process and its Application to MicroHotplates

    KAUST Repository

    Lizardo, Ernesto B.

    2013-05-08

    Micro-electro-mechanical systems (MEMS) became possible thanks to the silicon based technology used to fabricate integrated circuits. Originally, MEMS fabrication was limited to silicon based techniques and materials, but the expansion of MEMS applications brought the need of a wider catalog of materials, including polymers, now being used to fabricate MEMS. Polyimide is a very attractive polymer for MEMS fabrication due to its high temperature stability compared to other polymers, low coefficient of thermal expansion, low film stress and low cost. The goal of this thesis is to expand the Polyimide usage as structural material for MEMS by the development of a multi-user fabrication process for the integration of this polymer along with multiple metal layers on a silicon substrate. The process also integrates amorphous silicon as sacrificial layer to create free-standing structures. Dry etching is used to release the devices and avoid stiction phenomena. The developed process is used to fabricate platforms for micro-hotplate gas sensors. The fabrication steps for the platforms are described in detail, explaining the process specifics and capabilities. An initial testing of the micro-hotplate is presented. As the process was also used as educational tool, some designs made by students and fabricated with the Polyimide-MEMS process are also presented.

  8. Pressure analysis in the fabrication process of TRISO UO2-coated fuel particle

    International Nuclear Information System (INIS)

    Liu Malin; Shao Youlin; Liu Bing

    2012-01-01

    Highlights: ► The pressure signals during the real TRISO UO2-coated fuel particle fabrication process. ► A new relationship about the pressure drop change and the coated fuel particles properties. ► The proposed relationship is validated by experimental results during successive coating. ► A convenient method for monitoring the fluidized state during coating process. - Abstract: The pressure signals in the coating furnace are obtained experimentally from the TRISO UO 2 -coated fuel particle fabrication process. The pressure signals during the coating process are analyzed and a simplified relationship about the pressure drop change due to the coated layer is proposed based on the spouted bed hydrodynamics. The change of pressure drop is found to be consistent with the change of the combination factor about particle density, bed density, particle diameter and static bed height, during the successive coating process of the buffer PyC, IPyC, SiC and OPyC layer. The newly proposed relationship is validated by the experimental values. Based on this relationship, a convenient method is proposed for real-time monitoring the fluidized state of the particles in a high-temperature coating process in the spouted bed. It can be found that the pressure signals analysis is an effective method to monitor the fluidized state on-line in the coating process at high temperature up to 1600 °C.

  9. Evaluation of microplastic release caused by textile washing processes of synthetic fabrics.

    Science.gov (United States)

    De Falco, Francesca; Gullo, Maria Pia; Gentile, Gennaro; Di Pace, Emilia; Cocca, Mariacristina; Gelabert, Laura; Brouta-Agnésa, Marolda; Rovira, Angels; Escudero, Rosa; Villalba, Raquel; Mossotti, Raffaella; Montarsolo, Alessio; Gavignano, Sara; Tonin, Claudio; Avella, Maurizio

    2018-05-01

    A new and more alarming source of marine contamination has been recently identified in micro and nanosized plastic fragments. Microplastics are difficult to see with the naked eye and to biodegrade in marine environment, representing a problem since they can be ingested by plankton or other marine organisms, potentially entering the food web. An important source of microplastics appears to be through sewage contaminated by synthetic fibres from washing clothes. Since this phenomenon still lacks of a comprehensive analysis, the objective of this contribution was to investigate the role of washing processes of synthetic textiles on microplastic release. In particular, an analytical protocol was set up, based on the filtration of the washing water of synthetic fabrics and on the analysis of the filters by scanning electron microscopy. The quantification of the microfibre shedding from three different synthetic fabric types, woven polyester, knitted polyester, and woven polypropylene, during washing trials simulating domestic conditions, was achieved and statistically analysed. The highest release of microplastics was recorded for the wash of woven polyester and this phenomenon was correlated to the fabric characteristics. Moreover, the extent of microfibre release from woven polyester fabrics due to different detergents, washing parameters and industrial washes was evaluated. The number of microfibres released from a typical 5 kg wash load of polyester fabrics was estimated to be over 6,000,000 depending on the type of detergent used. The usage of a softener during washes reduces the number of microfibres released of more than 35%. The amount and size of the released microfibres confirm that they could not be totally retained by wastewater treatments plants, and potentially affect the aquatic environment. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Fabrication of uranium–americium mixed oxide pellet from microsphere precursors: Application of CRMP process

    Energy Technology Data Exchange (ETDEWEB)

    Remy, E. [Radiochemistry and Processes Department, CEA, Nuclear Energy Division, F-30207 Bagnols-sur-Cèze (France); Picart, S., E-mail: sebastien.picart@cea.fr [Radiochemistry and Processes Department, CEA, Nuclear Energy Division, F-30207 Bagnols-sur-Cèze (France); Delahaye, T. [Fuel Cycle Technology Department, CEA, Nuclear Energy Division, F-30207 Bagnols-sur-Cèze (France); Jobelin, I. [Radiochemistry and Processes Department, CEA, Nuclear Energy Division, F-30207 Bagnols-sur-Cèze (France); Lebreton, F.; Horlait, D. [Fuel Cycle Technology Department, CEA, Nuclear Energy Division, F-30207 Bagnols-sur-Cèze (France); Bisel, I. [Radiochemistry and Processes Department, CEA, Nuclear Energy Division, F-30207 Bagnols-sur-Cèze (France); Blanchart, P. [Heterogeneous Materials Research Group, Centre Européen de la Céramique, F-87068 Limoges (France); Ayral, A. [Institut Européen des Membranes, CNRS-ENSCM-UM2, CC47, University Montpellier 2, F-34095 Montpellier cedex 5 (France)

    2014-10-15

    Highlights: • Dust free process for (U,Am)O{sub 2} transmutation target fabrication. • Synthesis of U{sub 0.9}Am{sub 0.1}O{sub 2} mixed oxide microspheres from ion exchange resin. • Fabrication of dense U{sub 0.9}Am{sub 0.1}O{sub 2} pellet with 95% TD from mixed oxide microspheres. - Abstract: Mixed uranium–americium oxides are one of the materials envisaged for Americium Bearing Blankets dedicated to transmutation in fast neutron reactors. Recently, several processes have been developed in order to validate fabrication flowchart in terms of material specifications such as density and homogeneity but also to suggest simplifications for lowering industrial costs and hazards linked to dust generation of highly contaminating and irradiating compounds. This study deals with the application of an innovative route using mixed oxide microspheres obtained from metal loaded resin bead calcination, called Calcined Resin Microsphere Pelletization (CRMP). The synthesis of mixed oxide microsphere precursor of U{sub 0.9}Am{sub 0.1}O{sub 2±δ} is described as well as its characterisation. The use of this free-flowing precursor allows the pressing and sintering of one pellet of U{sub 0.9}Am{sub 0.1}O{sub 2±δ}. The ceramic obtained was characterised and results showed that its microstructure is dense and homogeneous and its density attains 95% of the theoretical density. This study validates the scientific feasibility of the CRMP process applied to the fabrication of uranium and americium-containing materials.

  11. Printing Outside the Box: Additive Manufacturing Processes for Fabrication of Large Aerospace Structures

    Science.gov (United States)

    Babai, Majid; Peters, Warren

    2015-01-01

    To achieve NASA's mission of space exploration, innovative manufacturing processes are being applied to the fabrication of propulsion elements. Liquid rocket engines (LREs) are comprised of a thrust chamber and nozzle extension as illustrated in figure 1 for the J2X upper stage engine. Development of the J2X engine, designed for the Ares I launch vehicle, is currently being incorporated on the Space Launch System. A nozzle extension is attached to the combustion chamber to obtain the expansion ratio needed to increase specific impulse. If the nozzle extension could be printed as one piece using free-form additive manufacturing (AM) processes, rather than the current method of forming welded parts, a considerable time savings could be realized. Not only would this provide a more homogenous microstructure than a welded structure, but could also greatly shorten the overall fabrication time. The main objective of this study is to fabricate test specimens using a pulsed arc source and solid wire as shown in figure 2. The mechanical properties of these specimens will be compared with those fabricated using the powder bed, selective laser melting technology at NASA Marshall Space Flight Center. As printed components become larger, maintaining a constant temperature during the build process becomes critical. This predictive capability will require modeling of the moving heat source as illustrated in figure 3. Predictive understanding of the heat profile will allow a constant temperature to be maintained as a function of height from substrate while printing complex shapes. In addition, to avoid slumping, this will also allow better control of the microstructural development and hence the properties. Figure 4 shows a preliminary comparison of the mechanical properties obtained.

  12. Progress in high-efficient solution process organic photovoltaic devices fundamentals, materials, devices and fabrication

    CERN Document Server

    Li, Gang

    2015-01-01

    This book presents an important technique to process organic photovoltaic devices. The basics, materials aspects and manufacturing of photovoltaic devices with solution processing are explained. Solution processable organic solar cells - polymer or solution processable small molecules - have the potential to significantly reduce the costs for solar electricity and energy payback time due to the low material costs for the cells, low cost and fast fabrication processes (ambient, roll-to-roll), high material utilization etc. In addition, organic photovoltaics (OPV) also provides attractive properties like flexibility, colorful displays and transparency which could open new market opportunities. The material and device innovations lead to improved efficiency by 8% for organic photovoltaic solar cells, compared to 4% in 2005. Both academic and industry research have significant interest in the development of this technology. This book gives an overview of the booming technology, focusing on the solution process fo...

  13. Fabrication, properties and microstructure of the YBCO superconductor prepared by the powder melting process

    International Nuclear Information System (INIS)

    Lian, Zhou; Pingxiang, Zhang; Keguang, Wang; Jingrong, Wang; Zehua, Du; Ping, Ji

    1992-01-01

    Many studies of critical current density (Jc) from the point of view of application in liquid nitrogen have been made since the discovery of 90K YBa 2 Cu 3 O y (YBCO) superconductor. It is believed that the weak links between grains are responsible for the low Jc of sintered YBCO at magnetic fields. In this work, the authors propose a new approach -- the powder melting process (PMP) -- through which high Jc YBCO conductor have been fabricated using precursor powders of 211 and Ba-Cu-O phase, instead of 123 phase, as starting materials. The current density of PMP YBCO sample has been over 71000A/cm 2 at 1T, 77K without quench. The SEM and TEM study revealed the microstructural characteristics of PMP YBCO sample, well distributed fine 211 phase particles, microcracks-free, very clean grain boundaries and high density of crystal defects, which are believed to be responsible for its high Jc(B) values. Another direction to develop PMP is to reduce the melting temperature, which is essential for the fabrication of YBCO tape with metal substrate. A discussion is given of effects of processing parameters and microstructure on the technological advantages of this method. The YBCO conductors were fabricated via the continuously partial melting and unidirectional resolidification steps of the process using precursor powders of Y 2 BaCuO 5 and Ba-Cu-O phase as starting materials. Since the process enables the liquid phase to react fully with the fine 211 particles during the peritectic, no CuO and BaCuO 2 phase remained in 123 matrix. Strong flux pinning effect was introduced by the fine well-dispersive 211 particles via the very dense crystal defects induced around them. This new approach has potential for the fabrication of oxide conductor with metal substrates since its melting temperature is lower than that of other melting process by 50-70 degrees C. The authors have fabricated YBCO/Ag tape via PMP in N 2 atmosphere

  14. Numerical study on fabricating rectangle microchannel in microfluidic chips by glass molding process

    Science.gov (United States)

    Wang, Tao; Chen, Jing; Zhou, Tianfeng

    2017-09-01

    This paper studied the glass molding process (GMP) for fabricating a typical microstructure of glass microfluidic chips, i. e., rectangle microchannel, on soda-lime glass by finite element method. More than 100 models were established on the platform of Abaqus/Standard. The influence of parameters, i. e., temperature, aspect ratio, side wall angle and friction coefficient on deformation were studied, and the predicted morphology of the molded microchannel were presented as well. The research could provide fundamental experience for optimizing GMP process in the future.

  15. Ceramic matrix composite article and process of fabricating a ceramic matrix composite article

    Science.gov (United States)

    Cairo, Ronald Robert; DiMascio, Paul Stephen; Parolini, Jason Robert

    2016-01-12

    A ceramic matrix composite article and a process of fabricating a ceramic matrix composite are disclosed. The ceramic matrix composite article includes a matrix distribution pattern formed by a manifold and ceramic matrix composite plies laid up on the matrix distribution pattern, includes the manifold, or a combination thereof. The manifold includes one or more matrix distribution channels operably connected to a delivery interface, the delivery interface configured for providing matrix material to one or more of the ceramic matrix composite plies. The process includes providing the manifold, forming the matrix distribution pattern by transporting the matrix material through the manifold, and contacting the ceramic matrix composite plies with the matrix material.

  16. Analysis of fabrication process for AP1000 passive residual heat removal heat exchanger

    International Nuclear Information System (INIS)

    Gao Yongjun

    2011-01-01

    This paper introduces the design parameters of the passive residual heat removal heat exchanger for American advanced passive pressurized water reactor (AP1000), describes the fabrication process for the head, tubesheet, heat exchange tube, corrugated plate and support frame assembly of the heat exchanger, mainly in terms of material, forging, welding, and heat treatment, and also analyzes the crucial steps for the support frame assembling, tubesheet plate welding, tube penetration welding of C tube bundle, closure/head welding, heat treatment, hydraulic (pressure) test, and etc. in the process of heat exchanger assembling. (author)

  17. Low cost fabrication and assembly process for re-usable 3D polydimethylsiloxane (PDMS) microfluidic networks

    CSIR Research Space (South Africa)

    Land, K

    2011-09-01

    Full Text Available for a PDMS device of a day is greatly reduced. III. CONCLUSION A low cost, convenient fabrication process for PDMS casting and assembly has been shown. The casting process reduces PDMS usage by casting only the functional part and pro- duces parts.... Scherer, and S. R. Quake, Science 288, 113 (2000). 12F. J. Blanco, M. Agirregabiria, J. Garcia, J. Berganzo, M. Tijero, M. T. Arroyo, J. M. Ruano, I. Aramburu, and K. May- ora, J. Micromech. Microeng. 14, 1047 (2004). 13J. R. Anderson, D. T. Chiu, R. J...

  18. Innovative fabrication processing of advanced composite materials concepts for primary aircraft structures

    Science.gov (United States)

    Kassapoglou, Christos; Dinicola, Al J.; Chou, Jack C.

    1992-01-01

    The autoclave based THERM-X(sub R) process was evaluated by cocuring complex curved panels with frames and stiffeners. The process was shown to result in composite parts of high quality with good compaction at sharp radius regions and corners of intersecting parts. The structural properties of the postbuckled panels fabricated were found to be equivalent to those of conventionally tooled hand laid-up parts. Significant savings in bagging time over conventional tooling were documented. Structural details such as cocured shear ties and embedded stiffener flanges in the skin were found to suppress failure modes such as failure at corners of intersecting members and skin stiffeners separation.

  19. The Application of Friction Stir Processing to the Fabrication of Magnesium-Based Foams

    Directory of Open Access Journals (Sweden)

    Azizieh M.

    2017-12-01

    Full Text Available In the present paper, friction stir processing (FSP is used to fabricate magnesium-based nanocomposite foams. The effects of the number of FSP passes, TiH2 to Al2O3 weight ratio, and foaming temperature; on the pore distribution and porosity are described. The results indicate that a minimum TiH2 to Al2O3 weight ratio is necessary to provide the best pore distribution and porosity. Closed-cell porous magnesium with a porosity of about 17.5% was successfully fabricated using 4-pass FSP at 800 rpm, by adding 5 mass% TiH2 and 3.5 mass% Al2O3; at a holding temperature of 858 K, and a holding time of 45 min.

  20. FABRICE process for the refrabrication of experimental pins in a hot cell, from pins pre-irradiated in power reactors

    International Nuclear Information System (INIS)

    Vignesoult, N.; Atabek, R.; Ducas, S.

    1982-06-01

    The Fabrice ''hot cell refabrication'' process for small pins from very long irradiated fuel elements was developed at the CEA to allow parametric studies of the irradiation behavior of pins from nuclear power plants. Since this operation required complete assurance of the validity of the process, qualification of the fabrication was performed on test pins, refabricated in the hot cell, as well as irradiation qualification. The latter qualification was intended to demonstrate that, in identical experimental irradiation conditions, the refabricated Fabrice pins behaved in the same way as whole pins with the same initial characteristics. This qualification of the Fabrice process, dealing with more than twenty pins at different burnups, showed that fabrication did not alter: the inherent characteristics of the sampled fuel element and the irradiation behavior of the sampled fuel element [fr

  1. Fabrication of Li2TiO3 pebbles by a freeze drying process

    International Nuclear Information System (INIS)

    Lee, Sang-Jin; Park, Yi-Hyun; Yu, Min-Woo

    2013-01-01

    Li 2 TiO 3 pebbles were successfully fabricated by using a freeze drying process. The Li 2 TiO 3 slurry was prepared using a commercial powder of particle size 0.5–1.5 μm and the pebble pre-form was prepared by dropping the slurry into liquid nitrogen through a syringe needle. The droplets were rapidly frozen, changing their morphology to spherical pebbles. The frozen pebbles were dried at −10 °C in vacuum. To make crack-free pebbles, some glycerin was employed in the slurry, and long drying time and a low vacuum condition were applied in the freeze drying process. In the process, the solid content in the slurry influenced the spheroidicity of the pebble green body. The dried pebbles were sintered at 1200 °C in an air atmosphere. The sintered pebbles showed almost 40% shrinkage. The sintered pebbles revealed a porous microstructure with a uniform pore distribution and the sintered pebbles were crushed under an average load of 50 N in a compressive strength test. In the present study, a freeze drying process for fabrication of spherical Li 2 TiO 3 pebbles is introduced. The processing parameters, such as solid content in the slurry and the conditions of freeze drying and sintering, are also examined

  2. Engineering structure design and fabrication process of small sized China helium-cooled solid breeder test blanket module

    International Nuclear Information System (INIS)

    Wang Zeming; Chen Lu; Hu Gang

    2014-01-01

    Preliminary design and analysis for china helium-cooled solid breeder (CHHC-SB) test blanket module (TBM) have been carried out recently. As partial verification that the original size module was reasonable and the development process was feasible, fabrication work of a small sized module was to be carried out targetedly. In this paper, detailed design and structure analysis of small sized TBM was carried out based on preliminary design work, fabrication process and integrated assembly process was proposed, so a fabrication for the trial engineering of TBM was layed successfully. (authors)

  3. Fabrication process optimization for improved mechanical properties of Al 7075/SiCp metal matrix composites

    Directory of Open Access Journals (Sweden)

    Dipti Kanta Das

    2016-04-01

    Full Text Available Two sets of nine different silicon carbide particulate (SiCp reinforced Al 7075 Metal Matrix Composites (MMCs were fabricated using liquid metallurgy stir casting process. Mean particle size and weight percentage of the reinforcement were varied according to Taguchi L9 Design of Experiments (DOE. One set of the cast composites were then heat treated to T6 condition. Optical micrographs of the MMCs reveal consistent dispersion of reinforcements in the matrix phase. Mechanical properties were determined for both as-cast and heat treated MMCs for comparison of the experimental results. Linear regression models were developed for mechanical properties of the heat treated MMCs using list square method of regression analysis. The fabrication process parameters were then optimized using Taguchi based grey relational analysis for the multiple mechanical properties of the heat treated MMCs. The largest value of mean grey relational grade was obtained for the composite with mean particle size 6.18 µm and 25 weight % of reinforcement. The optimal combination of process parameters were then verified through confirmation experiments, which resulted 42% of improvement in the grey relational grade. Finally, the percentage of contribution of each process parameter on the multiple performance characteristics was calculated through Analysis of Variance (ANOVA.

  4. Progresses in cMUT device fabrication using low temperature processes

    Science.gov (United States)

    Bahette, E.; Michaud, J. F.; Certon, D.; Gross, D.; Alquier, D.

    2014-04-01

    In this paper, we present an original fabrication process of capacitive micromachined ultrasonic transducers (cMUTs) using a low temperature method for high frequency medical imaging applications. The process, which is limited to 400 °C, is based on surface micromachining. The material choices are adapted in order to respect the thermal specifications allowing monolithic integration. Thus, we have found alternative methods to replace the usual high temperature steps in cMUT elaboration. In this way, a nickel silicide layer, presenting good physical and electrical characteristics, is used as a bottom electrode. The membrane, silicon nitride, is deposited using a 200 °C PECVD process. Then, a metallic layer is chosen as a sacrificial layer, in order to achieve the cavity. For that, nickel has been chosen due to its low roughness and its high etching selectivity during the excavation. After their fabrication, the transducers have been tested to verify their functionality and, thus, to validate this low temperature process. Device physical properties have been determined by electrical and optical measurement in air. We evaluated resonance frequency, collapse voltage and electromechanical coupling coefficient in accordance with the simulation. Eventually, low charging effects and low initial deflections can predict good long-term use and ageing of the cMUTs.

  5. Progresses in cMUT device fabrication using low temperature processes

    International Nuclear Information System (INIS)

    Bahette, E; Michaud, J F; Certon, D; Gross, D; Alquier, D

    2014-01-01

    In this paper, we present an original fabrication process of capacitive micromachined ultrasonic transducers (cMUTs) using a low temperature method for high frequency medical imaging applications. The process, which is limited to 400 °C, is based on surface micromachining. The material choices are adapted in order to respect the thermal specifications allowing monolithic integration. Thus, we have found alternative methods to replace the usual high temperature steps in cMUT elaboration. In this way, a nickel silicide layer, presenting good physical and electrical characteristics, is used as a bottom electrode. The membrane, silicon nitride, is deposited using a 200 °C PECVD process. Then, a metallic layer is chosen as a sacrificial layer, in order to achieve the cavity. For that, nickel has been chosen due to its low roughness and its high etching selectivity during the excavation. After their fabrication, the transducers have been tested to verify their functionality and, thus, to validate this low temperature process. Device physical properties have been determined by electrical and optical measurement in air. We evaluated resonance frequency, collapse voltage and electromechanical coupling coefficient in accordance with the simulation. Eventually, low charging effects and low initial deflections can predict good long-term use and ageing of the cMUTs. (paper)

  6. Influence of Fabricating Process on Gas Sensing Properties of ZnO Nanofiber-Based Sensors

    Science.gov (United States)

    Xu, Lei; Wang, Rui; Liu, Yong; Dong, Liang

    2011-04-01

    ZnO nanofibers are synthesized by an electrospinning method and characterized by x-ray diffraction (XRD) and scanning electron microscopy (SEM). Two types of gas sensors are fabricated by loading these nanofibers as the sensing materials and their performances are investigated in detail. Compared with the sensors based on traditional ceramic tubes with Au electrodes (traditional sensors), the sensors fabricated by spinning ZnO nanofibers on ceramic planes with Ag-Pd electrodes (plane sensors) exhibit much higher sensing properties. The sensitivity for the plane sensors is about 30 to 100 ppm ethanol at 300°C, while the value is only 13 for the traditional sensors. The response and recovery times are about 2 and 3s for the plane sensors and are 3 and 6s for the traditional sensors, respectively. Lower minimum-detection-limit is also found for the plane sensors. These improvements are explained by considering the morphological damage in the fabricating process for traditional sensors. The results suggest that the plane sensors are more suitable to sensing investigation for higher veracity.

  7. Rapsodie first core manufacture. 1. part: processing plant; Fabrication du premier coeur de rapsodie. Premiere partie: l'atelier de fabrication

    Energy Technology Data Exchange (ETDEWEB)

    Masselot, Y.; Bataller, S.; Ganivet, M.; Guillet, H.; Robillard, A.; Stosskopf, F. [Commissariat a l' Energie Atomique, Cadarache (France). Centre d' Etudes Nucleaires

    1968-07-01

    This report is the first in a series of three describing the processes, results and peculiar technical problems related to the manufacture of the first core of the fast reactor Rapsodie. A detailed study of manufacturing processes(pellets, pins, fissile sub-assemblies), the associated testings (raw materials, processed pellets and pins, sub-assemblies before delivery), manufacturing facilities and improvements for a second campaign are described. (author) [French] Ce rapport est le premier d'une serie de trois qui decrivent les procedes, les resultats et les problemes techniques particuliers de la fabrication du du premier coeur de la pile a neutrons rapides Rapsodie. Il comporte une etude detaillee des procedes de fabrication (pastilles, aiguilles, assemblages combustibles) et des methodes de controle associees (matieres premieres, pastilles et aiguilles en cours de fabrication, assemblages fissiles avant livraison), ainsi qu'une decription complete des installations de l'atelier de fabrication et les modifications apportees pour une deuxieme campagne. (auteur)

  8. A casting based process to fabricate 3D alginate scaffolds and to investigate the influence of heat transfer on pore architecture during fabrication

    International Nuclear Information System (INIS)

    Parks, W.M.; Guo, Y.B.

    2008-01-01

    The fabrication of 3-dimensional (3D) tissue scaffolds is a competitive approach to engineered tissues. An ideal tissue scaffold must be highly porous, biocompatible, biodegradable, easily processed and cost-effective, and have adequate mechanical properties. A casting based process has been developed in this study to fabricate 3D alginate tissue scaffolds. The alginate/calcium gluconate hydrogel was quenched in a glass mold and freeze dried to form a highly porous tissue scaffold whose tiny pores retain the shape of the ice crystals during quenching. Knowing that the water in the alginate hydrogel would form ice crystals if frozen and that different cooling conditions may dramatically influence the pore architecture, the speed and direction of the heat transfer in freeze drying hydrogel were examined with regard to pore size and orientation. The pore architecture at the different locations of the fabricated scaffolds was characterized using scanning electron microscopy. The fabricated scaffolds consist of pores that are highly interconnected, with a diameter about 200 μm (average diameter of a capillary) to permit blood vessel penetration. It also has been found that the pore size, orientation, and uniformity are significantly affected by the condition of heat transfer during freeze drying. Tailoring the pore architecture of the scaffolds is feasible by controlling heat transfer. This study provides an insight on pore architecture formation and control by altered process parameters

  9. Integral system for computer aided design of power line transmission towers; Sistema integral para el diseno asistido por computadora de torres de transmision

    Energy Technology Data Exchange (ETDEWEB)

    Nagore, Gabriel [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1986-12-31

    The profitable use of the advantages offered by the computer aided design, through the integral system for the structural design of power transmission towers (SIDETT) will contribute to facilitate and improve the design of the structures that link the electric power generation centers with the consumers. [Espanol] El aprovechamiento de las ventajas que ofrece el diseno asistido por computadora, a traves del sistema integral para el diseno estructural de torres de transmision (SIDETT), contribuira a agilizar y mejorar el diseno de las estructuras que enlazan los centros de generacion de energia electrica con los consumidores.

  10. Objective measure of thread characteristics in non-closely woven fabrics by image processing

    Science.gov (United States)

    Escofet, Jaume; Ralló, Miquel; Tàpias, Montserrat

    2009-08-01

    A digital image processing approach to develop an automatic method for the objective measure of some thread parameters in a non closely-woven fabric is presented. The parameters addressed by this method are thickness, periodicity, regularity, area of holes between threads and cover factor. Applied techniques range from image thresholding for the segmentation of the threads from the background, to morphological operations such as skeletonization and non-lineal filters. They are successfully applied to segment vertical and horizontal lines describing the geometry of the threads. The mentioned parameters are derived from further labeling of the skeletonized images.

  11. Cliché fabrication method using precise roll printing process with 5 um pattern width

    Science.gov (United States)

    Shin, Yejin; Kim, Inyoung; Oh, Dong-Ho; Lee, Taik-Min

    2016-09-01

    Among the printing processes for printed electronic devices, gravure offset and reverse offset method have drawn attention for its fine pattern printing possibility. These printing methods use cliché, which has critical effect on the final product precision and quality. In this research, a novel precise cliché replica method is proposed. It consists of copper sputtering, precise mask pattern printing with 5 um width using reverse offset printing, Ni electroplating, lift-off, etching, and DLC coating. We finally compare the fabricated replica cliché with the original one and print out precise patterns using the replica cliché.

  12. Information-management data base for fusion-target fabrication processes

    International Nuclear Information System (INIS)

    Reynolds, J.

    1982-01-01

    A computer-based data-management system has been developed to handle data associated with target-fabrication processes including glass microballoon characterization, gas filling, materials coating, and storage locations. The system provides automatic data storage and computation, flexible data-entry procedures, fast access, automated report generation, and secure data transfer. It resides on a CDC CYBER 175 computer and is compatible with the CDC data-base-language Query Update, but is based on custom FORTRAN software interacting directly with the CYBER's file-management system. The described data base maintains detailed, accurate, and readily available records of fusion targets information

  13. Experimental and Numerical Simulation Research on Micro-Gears Fabrication by Laser Shock Punching Process

    OpenAIRE

    Huixia Liu; Jianwen Li; Zongbao Shen; Qing Qian; Hongfeng Zhang; Xiao Wang

    2015-01-01

    The aim of this paper is to fabricate micro-gears via laser shock punching with Spitlight 2000 Nd-YAG Laser, and to discuss effects of process parameters namely laser energy, soft punch properties and blank-holder on the quality of micro-gears deeply. Results show that dimensional accuracy is the best shocked at 1690 mJ. Tensile fracture instead of shear fracture is the main fracture mode under low laser energy. The soft punch might cause damage to punching quality when too high energy is emp...

  14. Evaluation of Three Different Processing Techniques in the Fabrication of Complete Dentures

    Science.gov (United States)

    Chintalacheruvu, Vamsi Krishna; Balraj, Rajasekaran Uttukuli; Putchala, Lavanya Sireesha; Pachalla, Sreelekha

    2017-01-01

    Aims and Objectives: The objective of the present study is to compare the effectiveness of three different processing techniques and to find out the accuracy of processing techniques through number of occlusal interferences and increase in vertical dimension after denture processing. Materials and Methods: A cross-sectional study was conducted on a sample of 18 patients indicated for complete denture fabrication was selected for the study and they were divided into three subgroups. Three processing techniques, compression molding and injection molding using prepolymerized resin and unpolymerized resin, were used to fabricate dentures for each of the groups. After processing, laboratory-remounted dentures were evaluated for number of occlusal interferences in centric and eccentric relations and change in vertical dimension through vertical pin rise in articulator. Data were analyzed using statistical test ANOVA and SPSS software version 19.0 by IBM was used. Results: Data obtained from three groups were subjected to one-way ANOVA test. After ANOVA test, results with significant variations were subjected to post hoc test. Number of occlusal interferences with compression molding technique was reported to be more in both centric and eccentric positions as compared to the two injection molding techniques with statistical significance in centric, protrusive, right lateral nonworking, and left lateral working positions (P < 0.05). Mean vertical pin rise (0.52 mm) was reported to more in compression molding technique as compared to injection molding techniques, which is statistically significant (P < 0.001). Conclusions: Within the limitations of this study, injection molding techniques exhibited less processing errors as compared to compression molding technique with statistical significance. There was no statistically significant difference in processing errors reported within two injection molding systems. PMID:28713763

  15. Design of experiment characterization of microneedle fabrication processes based on dry silicon etching

    Science.gov (United States)

    Held, J.; Gaspar, J.; Ruther, P.; Hagner, M.; Cismak, A.; Heilmann, A.; Paul, O.

    2010-02-01

    This paper reports on the characterization of dry etching-based processes for the fabrication of silicon microneedles using a design of experiment (DoE) approach. The possibility of using such microneedles as protruding microelectrodes able to electroporate adherently growing cells and record intracellular potentials motivates the systematic analysis of the influence of etching parameters on the needle shape. Two processes are characterized: a fully isotropic etch process and a three-step etching approach. In the first case, the shape of the microneedles is defined by a single etch step. For the stepped method, the structures are realized using the following sequence: a first, isotropic step defines the tip; this is followed by anisotropic etching that increases the height of the needle; a final isotropic procedure thins the microneedle and sharpens its tip. From the various process parameters tested, it is concluded that the isotropic fabrication is influenced mostly by four process parameters, whereas six parameters dominantly govern the outcome of the stepped etching technique. The dependence of the needle shape on the etch mask diameter is also investigated. Microneedles with diameters down to the sub-micrometer range and heights below 10 µm are obtained. The experimental design is performed using the D-optimal method. The resulting geometry, i.e. heights, diameters and radii of curvature measured at different positions, is extracted from scanning electron micrographs of needle cross-sections obtained from cuts by focused ion beam. The process parameters are used as inputs and the geometry features of the microneedles as outputs for the analysis of the process.

  16. Design of experiment characterization of microneedle fabrication processes based on dry silicon etching

    International Nuclear Information System (INIS)

    Held, J; Gaspar, J; Ruther, P; Paul, O; Hagner, M; Cismak, A; Heilmann, A

    2010-01-01

    This paper reports on the characterization of dry etching-based processes for the fabrication of silicon microneedles using a design of experiment (DoE) approach. The possibility of using such microneedles as protruding microelectrodes able to electroporate adherently growing cells and record intracellular potentials motivates the systematic analysis of the influence of etching parameters on the needle shape. Two processes are characterized: a fully isotropic etch process and a three-step etching approach. In the first case, the shape of the microneedles is defined by a single etch step. For the stepped method, the structures are realized using the following sequence: a first, isotropic step defines the tip; this is followed by anisotropic etching that increases the height of the needle; a final isotropic procedure thins the microneedle and sharpens its tip. From the various process parameters tested, it is concluded that the isotropic fabrication is influenced mostly by four process parameters, whereas six parameters dominantly govern the outcome of the stepped etching technique. The dependence of the needle shape on the etch mask diameter is also investigated. Microneedles with diameters down to the sub-micrometer range and heights below 10 µm are obtained. The experimental design is performed using the D-optimal method. The resulting geometry, i.e. heights, diameters and radii of curvature measured at different positions, is extracted from scanning electron micrographs of needle cross-sections obtained from cuts by focused ion beam. The process parameters are used as inputs and the geometry features of the microneedles as outputs for the analysis of the process.

  17. Nanosized-Particle Dispersion-Strengthened Al Matrix Composites Fabricated by the Double Mechanical Alloying Process.

    Science.gov (United States)

    Kim, Chungseok

    2018-03-01

    The objective of this study was to fabricate an Al metal matrix composite strengthened by nanosized Al3Ti particles via double mechanical alloying process. Several Al-xTi alloys were fabricated, including Al-12%Ti, Al-15%Ti, and Al-12%Ti-1%Y2O3. The lattice parameter of as-milled state was calculated to be 4.0485 Å; after a milling time of 540 min, it was 4.0401 Å. This decrease was induced by Ti solutionizing into the Al matrix. The equivalent size of a coarse Al3Ti particle was 200-500 nm after the heat treatment; however, the particles were uniformly distributed and were refined through the MA2 process. The particle size of a Al3Ti phase was 30 nm or less, and the particles were uniformly distributed. These particles remained in a fine state in the matrix without growth and coarsening, even after the hot extrusion process. The microstructure of hot extruded alloys consisted of a uniform distribution of Al3Ti particles and other dispersoids in the Al matrix.

  18. System programs design of motors; Sistema de programas de diseno de motores

    Energy Technology Data Exchange (ETDEWEB)

    Diaz Gonzalez Palomas, Oscar; Ciprian Avila, Fernando [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1988-12-31

    This paper describes the objective of creating the program system for induction motors design SIPRODIMO, its scope, its general characteristics, its structure and the results obtained with its application, as well as the service capacity developed by the Motors Area of the Instituto de Investigaciones Elctricas. [Espanol] En este articulo se describe el objetivo de crear el sistema de programas de diseno de motores de induccion, Siprodimo, su alcance, sus caracteristicas generales, su estructura y los resultados obtenidos con su aplicacion, asi como la capacidad de servicio desarrollada por el area de motores, del Instituto de Investigaciones Electricas.

  19. Feed-water heaters alternative design comparison; Comparacion de disenos alternativos de calentadores

    Energy Technology Data Exchange (ETDEWEB)

    Torres Toledano, Gerardo [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1988-12-31

    A procedure is presented for the alternative design comparison of feed water heaters, based in the failure records of damaged tubes during operation. The procedure is used for cases in which non-continuous or random inspections are made to the feed-water heaters. [Espanol] Se presenta un procedimiento para comparar disenos alternativos de calentadores, basandose en los registros de fallas de los tubos rotos acumuladas durante su operacion. El procedimiento se emplea para casos en los que se realizan inspecciones a los calentadores no continuas, ya sea periodicas o al azar.

  20. Design, fabrication, and application of a directional thermal processing system for controlled devitrification of metallic glasses

    Science.gov (United States)

    Meyer, Megan Anne Lamb

    The potential of using metallic glass as a pathway to obtaining novel morphologies and metastable phases has been garnering attention since their discovery. Several rapid solidification techniques; such as gas atomization, melt spinning, laser melting, and splat quenching produce amorphous alloys. A directional thermal processing system (DTPS) was designed, fabricated and characterized for the use of zone processing or gradient-zone processing of materials. Melt-spun CuZr metallic glass alloy was subjected to the DTPS and the relaxation and crystallization responses of the metallic glass were characterized. A range of processing parameters were developed and analyzed that would allow for devitrification to occur. The relaxation and crystallization responses were compared with traditional heat treatment methods of metallic glasses. The new processing method accessed equilibrium and non-equilibrium phases of the alloy and the structures were found to be controllable and sensitive to processing conditions. Crystallized fraction, crystallization onset temperature, and structural relaxation were controlled through adjusting the processing conditions, such as the hot zone temperature and sample velocity. Reaction rates computed from isothermal (TTT) transformation data were not found to be reliable, suggesting that the reaction kinetics are not additive. This new processing method allows for future studying of the thermal history effects of metallic glasses.

  1. Design, construction and characterization of a rural solar furnace; Diseno, construccion y caracterizacion de un horno solar rural

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez Luna, Gabriela

    2001-06-15

    centigrade, followed of the condition using 6 liters of oil, in which a maximum temperature of 115 centigrade was obtained and in the tests with 6 liters of water as load a maximum temperature of 95 centigrade was registered. In these tests the temperature of the oil surpasses 60 centigrade during an approximate period of 7 hours and is higher than 80 centigrade by a lapse of 5 hours. The water temperature is higher than 60 centigrade for a period of more than 5 hours and during 3 hours is higher than 80 centigrade. These results are satisfactory, because they assure the accomplishment of the process of baking inside the furnace. A calculation program was elaborated to implement the theoretical model of the concentration. This program reads the data of radiation intensity in the horizontal plane supplied by the weather station of the CIE and determines the incident radiation in the furnace collector. The theoretical model of the thermal behavior was implemented in another computer program; this program reads the data of the incident radiation in the collector of the furnace and the data of room temperature and calculates the temperature of the furnace as a time function. The model overestimates the temperature reached in the furnace, nevertheless reproduces qualitatively the thermal behavior of the same. In spite of the limitations of the theoretical model, this can be of utility in achieving the reproduction of the temperature of the load experimentally registered, through an effective coefficient of heat losses and an effective coefficient of heat capacity, characteristic of each one of the conditions of the test. [Spanish] Esta tesis presenta el diseno, construccion y caracterizacion de un horno solar tipo caja para su uso en comunidades rurales en la zona intertropical. El trabajo presentado en esta tesis parte del diseno opto-geometrico de un horno solar tipo caja propuesto por un entusiasta grupo de jovenes estudiantes (Acosta et al., 1996, Vazquez et al., 1998

  2. Antimicrobial nano-silver non-woven polyethylene terephthalate fabric via an atmospheric pressure plasma deposition process

    Science.gov (United States)

    Deng, Xiaolong; Yu Nikiforov, Anton; Coenye, Tom; Cools, Pieter; Aziz, Gaelle; Morent, Rino; de Geyter, Nathalie; Leys, Christophe

    2015-05-01

    An antimicrobial nano-silver non-woven polyethylene terephthalate (PET) fabric has been prepared in a three step process. The fabrics were first pretreated by depositing a layer of organosilicon thin film using an atmospheric pressure plasma system, then silver nano-particles (AgNPs) were incorporated into the fabrics by a dipping-dry process, and finally the nano-particles were covered by a second organosilicon layer of 10-50 nm, which acts as a barrier layer. Different surface characterization techniques like SEM and XPS have been implemented to study the morphology and the chemical composition of the nano-silver fabrics. Based on these techniques, a uniform immobilization of AgNPs in the PET matrix has been observed. The antimicrobial activity of the treated fabrics has also been tested using P. aeruginosa, S. aureus and C. albicans. It reveals that the thickness of the barrier layer has a strong effect on the bacterial reduction of the fabrics. The durability and stability of the AgNPs on the fabrics has also been investigated in a washing process. By doing so, it is confirmed that the barrier layer can effectively prevent the release of AgNPs and that the thickness of the barrier layer is an important parameter to control the silver ions release.

  3. Fabrication of Coupling Structure and Composite Properties by Electro-brush Plating and Laser Processing

    Directory of Open Access Journals (Sweden)

    LI Jing

    2016-12-01

    Full Text Available To obtain a superhydrophobic aluminum alloy surface, a kind of special coupling structure was fabricated on the aluminum alloy surface by a couple ways which was electro-brush plating combined with laser processing. The surface has excellent anti-adhesion and corrosion resistance property. The contact angle can reach as high as 155.1°, while the sliding angle less than 5.6°. The morphological feature, chemical structures, and wettability of resultant surfaces were characterized by scanning electronic microscope (SEM, X-ray diffraction (XRD and water contact angle measurements. The surface corrosion resistance was researched by a corrosion resistance experiment. The results show that surface consists of micro-scale grooves and like-cauliflower mastoids, the grooves in a regular arrangement with mastoid structures for a coupling structure on the surface. The special coupling structure makes the surface already have superhydrophobicity. The wettability of the surface changes from hydrophilicity to superhydrophobicity. There have no peaks from other phases can be detected between electro-brush plating surface and aluminum alloy substrates. The peak intensity is changed by laser processing, and the organization structure of the material is further refined. The corrosion resistance of the surface that is fabricated by couple ways improves.

  4. Solution-Processed Metal Coating to Nonwoven Fabrics for Wearable Rechargeable Batteries.

    Science.gov (United States)

    Lee, Kyulin; Choi, Jin Hyeok; Lee, Hye Moon; Kim, Ki Jae; Choi, Jang Wook

    2017-12-27

    Wearable rechargeable batteries require electrode platforms that can withstand various physical motions, such as bending, folding, and twisting. To this end, conductive textiles and paper have been highlighted, as their porous structures can accommodate the stress built during various physical motions. However, fabrics with plain weaves or knit structures have been mostly adopted without exploration of nonwoven counterparts. Also, the integration of conductive materials, such as carbon or metal nanomaterials, to achieve sufficient conductivity as current collectors is not well-aligned with large-scale processing in terms of cost and quality control. Here, the superiority of nonwoven fabrics is reported in electrochemical performance and bending capability compared to currently dominant woven counterparts, due to smooth morphology near the fiber intersections and the homogeneous distribution of fibers. Moreover, solution-processed electroless deposition of aluminum and nickel-copper composite is adopted for cathodes and anodes, respectively, demonstrating the large-scale feasibility of conductive nonwoven platforms for wearable rechargeable batteries. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Manufacturing processes in the textile industry. Expert Systems for fabrics production

    Directory of Open Access Journals (Sweden)

    Juan BULLON

    2017-03-01

    Full Text Available The textile industry is characterized by the economic activity whose objective is the production of fibres, yarns, fabrics, clothing and textile goods for home and decoration,as well as technical and industrial purposes. Within manufacturing, the Textile is one of the oldest and most complex sectors which includes a large number of sub-sectors covering the entire production cycle, from raw materials and intermediate products, to the production of final products. Textile industry activities present different subdivisions, each with its own traits. The length of the textile process and the variety of its technical processes lead to the coexistence of different sub-sectors in regards to their business structure and integration. The textile industry is developing expert systems applications to increase production, improve quality and reduce costs. The analysis of textile designs or structures includes the use of mathematical models to simulate the behavior of the textile structures (yarns, fabrics and knitting. The Finite Element Method (FEM has largely facilitated the prediction of the behavior of that textile structure under mechanical loads. For classification problems Artificial Neural Networks (ANNs haveproved to be a very effective tool as a quick and accurate solution. The Case-Based Reasoning (CBR method proposed in this study complements the results of the finite element simulation, mathematical modeling and neural networks methods.

  6. Fabrication of uranium-americium mixed oxide pellet from microsphere precursors: Application of CRMP process

    Science.gov (United States)

    Remy, E.; Picart, S.; Delahaye, T.; Jobelin, I.; Lebreton, F.; Horlait, D.; Bisel, I.; Blanchart, P.; Ayral, A.

    2014-10-01

    Mixed uranium-americium oxides are one of the materials envisaged for Americium Bearing Blankets dedicated to transmutation in fast neutron reactors. Recently, several processes have been developed in order to validate fabrication flowchart in terms of material specifications such as density and homogeneity but also to suggest simplifications for lowering industrial costs and hazards linked to dust generation of highly contaminating and irradiating compounds. This study deals with the application of an innovative route using mixed oxide microspheres obtained from metal loaded resin bead calcination, called Calcined Resin Microsphere Pelletization (CRMP). The synthesis of mixed oxide microsphere precursor of U0.9Am0.1O2±δ is described as well as its characterisation. The use of this free-flowing precursor allows the pressing and sintering of one pellet of U0.9Am0.1O2±δ. The ceramic obtained was characterised and results showed that its microstructure is dense and homogeneous and its density attains 95% of the theoretical density. This study validates the scientific feasibility of the CRMP process applied to the fabrication of uranium and americium-containing materials.

  7. Effects of atmosphere composition on fabrication process of hollow glass microspheres in drop-tower furnace

    International Nuclear Information System (INIS)

    Qi Xiaobo; Wei Sheng; Zhang Zhanwen; Li Bo; Chen Sufen; Shi Tao

    2010-01-01

    To fabricate high quality hollow glass microspheres (HGMs) for inertial confinement fusion (ICF) targets by solgel technology, effects of furnace atmosphere composition on the transformation process from gel particles to HGMs and the resulting quality of HGMs were investigated by numerical simulation and experiments. The results show that the furnace atmosphere composition significantly affects the heat and mass transfer process between particles/microspheres and furnace atmosphere, but the falling velocity of the particles/microspheres in drop-tower furnace changes only slightly with the furnace atmosphere compositions. The heating-up rate of gel particles in heat-absorbing stage increases remarkably with the increase of the content of helium in the furnace atmosphere and increasing the helium content accelerates effectively the encapsulation of gel particles. Consequently, higher helium content in furnace atmosphere will result in higher HGM yield with high quality and larger HGM aspect ratio. However, maintaining a proper proportion of helium in the furnace atmosphere is necessary to improve HGM surface smoothness. With the volume percentage of helium ranging from 50% to 80%, HGMs with high sphericity, concentricity and surface smoothness can be fabricated with high yield. (authors)

  8. Research on plant of metal fuel fabrication using casting process (2)

    International Nuclear Information System (INIS)

    Senda, Yasuhide; Yamada, Seiya

    2005-02-01

    In this research work for the metal fuel fabrication system (38 tHM/y), the studies of the concept of the main process equipments were performed based on the previous studies on the process design and the quality control system design. In this study the handling equipment of the products were also designed, according to these designs the handling periods were evaluated. Consequently the numbers of the equipments were assessed taking into account for the method of the blending the fuel composition. (1) Structural concept design of the major equipments, the fuel handling machine and the gravimetries in the main fabrication process. The structural concept were designed for the fuel composition blending equipment, the fuel pin assembling equipment, the sodium bonding equipment, the handling equipment for fuel slug palettes, the handling equipment for fuel pins and the gravimetries. (2) Re-assessment of the numbers of the equipments taking account of the handling periods. Based on the results of item (1) the periods were evaluated for the fuel slug and pin handling. Processing time of demolder is short, then the number of it is increased to two. Three vehicles are also added to transfer the slugs and a heel smoothly. (3) Design of the buffer storages. The buffer storages among the equipments were designed through the comparison of the process speed between the equipments taking into account for the handling periods. The required amount of the structural parts (for example cladding materials) was assessed for the buffer in the same manner and the amount of the buffer facilities were optimized. (author)

  9. CNEA developments in U-Mo-ZrY-4 mini plates and plates fabrication process

    International Nuclear Information System (INIS)

    López, M.; Picchetti, B.; Gonzalez, A.; Taboada, H.

    2013-01-01

    The Uranium Molybdenum alloy was the material chosen to develop the fabrication of high density nuclear fuel, due to its excellent behaviour under irradiation –a consequence of the metastable bcc crystalline structure-. At present, the study is focused on the application of this alloy to monolithic fuel plate development, which fuel core is a thin U-Mo layer. The Zircalloy-4 (Zry-4) alloy used as cladding material is extensively known in the nuclear industry due to its low neutron capture section efficiency and excellent mechanical and corrosion resistance properties. Miniplates fabrication process involves a welded compact made of two Zry-4 covers and a frame surrounding a monolithic U-Mo core, which is co rolled under high temperature. Molybdenum contains of 7% to 10% (mass) in U Mo alloys guarantees the presence of meta-stable bcc gamma phase and, at the same time, does not penalize the neutron economy due to Mo98 presence. In the case of U Mo monolithic miniplates relevant parameters of fabrication, considering the behaviour of the U-Mo alloys reported in many work and in order to optimize the o-rolling process, have been revised: co-rolling temperature, compressive stress and presence of gap. Under this experimental conditions can be studied the the interdiffusion layer, the binding between materials and the Dog Bone. The experimental results shows that 650ºC is an optimal co-rolling temperature; at higher temperatures not only a bigger interdiffusion layer is observed –this phenomenon can lead to a region enriched in Molybdenum- but also a bigger Dog Bone is obtained. Working at higher compressive stress has the same effect in relation to the interdiffusion layer. In addition, the absence of gases in the core is essential for the correct binding of the materials. Concerning the monolithic U-Mo plates fabrication, involved in the ALT FUTURE experiment a new workshop has been conditioned. The aim is to use all the valuable information collected during

  10. Wet-Lay Process - A Novel Approach to Scalable Fabrication of Tissue Scaffolds and Reinforcement Membranes

    Science.gov (United States)

    Wood, Andrew

    Fibrous materials received a great deal of interest in the fields of tissue engineering and regenerative medicine due to the beneficial cell-interactions and tunable properties for various biomedical applications. These materials are highly advantageous as they provide a large surface area for cellular attachment, proliferation, high porosity values for cellular in-growth, and the ability to modify the membrane to achieve desired responses to both mechanical loading as well as environmental stimuli. A prominent method currently used to fabricate such membranes is electrospinning which uses electrostatic forces to produce fibers on the range of nanometers giving them high morphological saliency to the native extra cellular matrix (ECM). These fibers are also advantageous mechanically with strength and flexibility due to their larger aspect ratio when compared to larger diameter micro/macro fibers. While this spinning technique has many advantages and has seen the most quantity of research in recent years, it does have its own set of drawbacks. Among them is the use cytotoxic solvents during processing which must be fully removed before implantation. In addition, since the fiber produced have smaller diameters, the resulting average pore-size of the scaffold is decreased which in turn hinders cellular penetration into the bulk scaffold. In this work, we have proposed and characterized a novel method called wet-lay process for the rapid fabrication of fibrous membranes for tissue scaffolds. Wet-laying is a method common to textiles and paper industry but unexplored for tissue scaffolds. Short fibers are first suspended in an aqueous bath and homogeneously dispersed using shear force. After draining away the aqueous solution, a nonwoven fibro-porous membrane is deposited onto the draining screen. The implementation of wet-laid membranes into weak hydrogel matrices has shown a reinforcement effect for the composite. Further analyses were carried out to determine the

  11. Fabrication of metal matrix composite by semi-solid powder processing

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Yufeng [Iowa State Univ., Ames, IA (United States)

    2011-01-01

    Various metal matrix composites (MMCs) are widely used in the automotive, aerospace and electrical industries due to their capability and flexibility in improving the mechanical, thermal and electrical properties of a component. However, current manufacturing technologies may suffer from insufficient process stability and reliability and inadequate economic efficiency and may not be able to satisfy the increasing demands placed on MMCs. Semi-solid powder processing (SPP), a technology that combines traditional powder metallurgy and semi-solid forming methods, has potential to produce MMCs with low cost and high efficiency. In this work, the analytical study and experimental investigation of SPP on the fabrication of MMCs were explored. An analytical model was developed to understand the deformation mechanism of the powder compact in the semi-solid state. The densification behavior of the Al6061 and SiC powder mixtures was investigated with different liquid fractions and SiC volume fractions. The limits of SPP were analyzed in terms of reinforcement phase loading and its impact on the composite microstructure. To explore adoption of new materials, carbon nanotube (CNT) was investigated as a reinforcing material in aluminum matrix using SPP. The process was successfully modeled for the mono-phase powder (Al6061) compaction and the density and density distribution were predicted. The deformation mechanism at low and high liquid fractions was discussed. In addition, the compaction behavior of the ceramic-metal powder mixture was understood, and the SiC loading limit was identified by parametric study. For the fabrication of CNT reinforced Al6061 composite, the mechanical alloying of Al6061-CNT powders was first investigated. A mathematical model was developed to predict the CNT length change during the mechanical alloying process. The effects of mechanical alloying time and processing temperature during SPP were studied on the mechanical, microstructural and

  12. Fabrication and characterization of solution processed vertically aligned ZnO microrods

    Energy Technology Data Exchange (ETDEWEB)

    Gadallah, A.-S., E-mail: agadallah@niles.edu.eg [Laboratoire de Nanotechnologie et d’Instrumentation Optique, Institut Charles Delaunay, CNRS UMR 6279, Université de Technologie de Troyes, 12 rue Marie Curie, BP 2060, 10010 Troyes Cedex (France); Department of Laser Sciences and Interactions, National Institute of Laser Enhanced Sciences, Cairo University, 12613 Giza (Egypt)

    2014-08-30

    Simple and effective cost high quality vertically aligned densely packed ZnO microrods have been prepared using solution processed two-step deposition process, specifically sol–gel spin coating combined with chemical bath deposition. X-ray diffraction pattern and scanning electron microscope show that there has been preferential crystal orientation along c-axis and the growth of the microrods has occurred normal to the glass substrate and the facets of the these microrods are hexagons. Photoluminescence measurements showed an emission band in the UV region and another weak band in the visible region with the emission intensity of UV band grows superlinearly with the excitation intensity. The film shows an electrical resistivity of 136 Ω cm as evaluated from four-point probe method. The fabricated film has been used as UV detector through Au/SiO{sub 2}/ZnO structure on glass substrate as the structure shows higher current under illumination compared to without illumination.

  13. Dielectric microwave absorbing material processed by impregnation of carbon fiber fabric with polyaniline

    Directory of Open Access Journals (Sweden)

    Luiza de Castro Folgueras

    2007-03-01

    Full Text Available It is a known fact that the adequate combination of components and experimental conditions may produce materials with specific requirements. This study presents the effect of carbon fiber fabric impregnation with polyaniline conducting polymer aiming at the radar absorbing material processing. The experiments consider the sample preparation with one and two impregnations. The prepared samples were evaluated by reflectivity measurements, in the frequency range of 8-12 GHz and scanning electron microscopy analyses. The correlation of the results shows that the quantity of impregnated material influences the performance of the processed microwave absorber. This study shows that the proposed experimental route provides flexible absorbers with absorption values of the incident radiation close to 87%.

  14. Dynamic compression of aluminum foam processed by a freeform fabrication technique

    International Nuclear Information System (INIS)

    Dannemann, Kathryn A.; Lankford, James Jr.; Nicholls, Arthur E.; Vaidyanathan, Ranji; Green, Catherine

    2004-01-01

    The compressive deformation behavior of a new type of aluminum foam was assessed under static and dynamic loading conditions. The aluminum foam investigated was processed by Advanced Ceramics Research using an extrusion freeform fabrication technique. The foam contained approximately 50 to 60% porosity. The dynamic compression response was evaluated in air using a split Hopkinson pressure bar (SHPB) system with aluminum bars, and strain rates ranging from 600 s-1 to 2000 s-1. Compression tests were also conducted at lower strain rates (10-3 s-1 to 4 s-1) to determine the extent of strain rate strengthening. The low strain rate tests were performed with a servo-controlled hydraulic test machine. The results were analyzed as a function of foam density, structure, and process conditions

  15. Concurrent engineering solution for the design of ship and offshore bracket parts and fabrication process

    Directory of Open Access Journals (Sweden)

    Tae-Won Kim

    2013-09-01

    Full Text Available Brackets in ships and offshore structures are added structures that can endure stress concentrations. In this study, a concurrent engineering solution was proposed, and a high strength low carbon cast steel alloy applicable to offshore structures was designed and developed. The yield strength and ultimate tensile strength of the designed steel were 480 and 600 MPa, respectively. The carbon equivalent of the steel was 0.446 with a weld crack susceptibility index of 0.219. The optimal structural design of the brackets for offshore structures was evaluated using ANSYS commercial software. The possibility of replacing an assembly of conventional built-up brackets with a single casting bulb bracket was verified. The casting process was simulated using MAGMAsoft commercial software, and a casting fabrication process was designed. For the proposed bulb bracket, it was possible to reduce the size and weight by approximately 30% and 50%, respectively, compared to the conventional type of bracket.

  16. Functional Circuitry on Commercial Fabric via Textile-Compatible Nanoscale Film Coating Process for Fibertronics.

    Science.gov (United States)

    Bae, Hagyoul; Jang, Byung Chul; Park, Hongkeun; Jung, Soo-Ho; Lee, Hye Moon; Park, Jun-Young; Jeon, Seung-Bae; Son, Gyeongho; Tcho, Il-Woong; Yu, Kyoungsik; Im, Sung Gap; Choi, Sung-Yool; Choi, Yang-Kyu

    2017-10-11

    Fabric-based electronic textiles (e-textiles) are the fundamental components of wearable electronic systems, which can provide convenient hand-free access to computer and electronics applications. However, e-textile technologies presently face significant technical challenges. These challenges include difficulties of fabrication due to the delicate nature of the materials, and limited operating time, a consequence of the conventional normally on computing architecture, with volatile power-hungry electronic components, and modest battery storage. Here, we report a novel poly(ethylene glycol dimethacrylate) (pEGDMA)-textile memristive nonvolatile logic-in-memory circuit, enabling normally off computing, that can overcome those challenges. To form the metal electrode and resistive switching layer, strands of cotton yarn were coated with aluminum (Al) using a solution dip coating method, and the pEGDMA was conformally applied using an initiated chemical vapor deposition process. The intersection of two Al/pEGDMA coated yarns becomes a unit memristor in the lattice structure. The pEGDMA-Textile Memristor (ETM), a form of crossbar array, was interwoven using a grid of Al/pEGDMA coated yarns and untreated yarns. The former were employed in the active memristor and the latter suppressed cell-to-cell disturbance. We experimentally demonstrated for the first time that the basic Boolean functions, including a half adder as well as NOT, NOR, OR, AND, and NAND logic gates, are successfully implemented with the ETM crossbar array on a fabric substrate. This research may represent a breakthrough development for practical wearable and smart fibertronics.

  17. Binder Jetting: A Novel Solid Oxide Fuel-Cell Fabrication Process and Evaluation

    Science.gov (United States)

    Manogharan, Guha; Kioko, Meshack; Linkous, Clovis

    2015-03-01

    With an ever-growing concern to find a more efficient and less polluting means of producing electricity, fuel cells have constantly been of great interest. Fuel cells electrochemically convert chemical energy directly into electricity and heat without resorting to combustion/mechanical cycling. This article studies the solid oxide fuel cell (SOFC), which is a high-temperature (100°C to 1000°C) ceramic cell made from all solid-state components and can operate under a wide range of fuel sources such as hydrogen, methanol, gasoline, diesel, and gasified coal. Traditionally, SOFCs are fabricated using processes such as tape casting, calendaring, extrusion, and warm pressing for substrate support, followed by screen printing, slurry coating, spray techniques, vapor deposition, and sputter techniques, which have limited control in substrate microstructure. In this article, the feasibility of engineering the porosity and configuration of an SOFC via an additive manufacturing (AM) method known as binder jet printing was explored. The anode, cathode and oxygen ion-conducting electrolyte layers were fabricated through AM sequentially as a complete fuel cell unit. The cell performance was measured in two modes: (I) as an electrolytic oxygen pump and (II) as a galvanic electricity generator using hydrogen gas as the fuel. An analysis on influence of porosity was performed through SEM studies and permeability testing. An additional study on fuel cell material composition was conducted to verify the effects of binder jetting through SEM-EDS. Electrical discharge of the AM fabricated SOFC and nonlinearity of permeability tests show that, with additional work, the porosity of the cell can be modified for optimal performance at operating flow and temperature conditions.

  18. La falta de financiacion publica hipoteca el futuro del acelerador de protones valenciano. La Universidad de Valencia tiene avanzado el diseno de este dispositivo de alta tecnologia

    CERN Document Server

    Jatvia, J M

    2002-01-01

    "La Universidad de Valencia tiene avanzado el diseno de un acelerador lineal de protones, cuya culminacion depende del compromiso del Consell en sufragar la plantilla que necesitaria el centro para estar operativo" (1 page).

  19. Preparation of highly hydrophobic cotton fabrics by modification with bifunctional silsesquioxanes in the sol-gel process

    Energy Technology Data Exchange (ETDEWEB)

    Przybylak, Marcin, E-mail: marcin.przybylak@ppnt.poznan.pl [Poznań Science and Technology Park, Adam Mickiewicz University Foundation, Rubież 46, 61-612 Poznań (Poland); Maciejewski, Hieronim, E-mail: maciejm@amu.edu.pl [Poznań Science and Technology Park, Adam Mickiewicz University Foundation, Rubież 46, 61-612 Poznań (Poland); Faculty of Chemistry, Adam Mickiewicz University, Umultowska 89b, 61-614 Poznań (Poland); Dutkiewicz, Agnieszka, E-mail: agdut@interia.pl [Poznań Science and Technology Park, Adam Mickiewicz University Foundation, Rubież 46, 61-612 Poznań (Poland)

    2016-11-30

    Highlights: • Fabric hydrophobization process using bifunctional silsesquioxanes was studied. • Superhydrophobic fabric was produced using fluorofunctional silsesquioxanes. • Surface of modified fabrics was analyzed using different techniques. - Abstract: The surface modification of cotton fabrics was carried out using two types of bifunctional fluorinated silsesquioxanes with different ratios of functional groups. The modification was performed either by one- or two-step process. Two methods, the sol-gel and the dip coating method were used in different configurations. The heat treatment and the washing process were applied after modification. The wettability of cotton fabric was evaluated by measuring water contact angles (WCA). Changes in the surface morphology were examined by scanning electron microscopy (SEM, SEM-LFD) and atomic force microscopy (AFM). Moreover, the modified fabrics were subjected to analysis of elemental composition of the applied coatings using SEM-EDS techniques. Highly hydrophobic textiles were obtained in all cases studied and one of the modifications resulted in imparting superhydrophobic properties. Most of impregnated textiles remained hydrophobic even after multiple washing process which shows that the studied modification is durable.

  20. Preparation of highly hydrophobic cotton fabrics by modification with bifunctional silsesquioxanes in the sol-gel process

    International Nuclear Information System (INIS)

    Przybylak, Marcin; Maciejewski, Hieronim; Dutkiewicz, Agnieszka

    2016-01-01

    Highlights: • Fabric hydrophobization process using bifunctional silsesquioxanes was studied. • Superhydrophobic fabric was produced using fluorofunctional silsesquioxanes. • Surface of modified fabrics was analyzed using different techniques. - Abstract: The surface modification of cotton fabrics was carried out using two types of bifunctional fluorinated silsesquioxanes with different ratios of functional groups. The modification was performed either by one- or two-step process. Two methods, the sol-gel and the dip coating method were used in different configurations. The heat treatment and the washing process were applied after modification. The wettability of cotton fabric was evaluated by measuring water contact angles (WCA). Changes in the surface morphology were examined by scanning electron microscopy (SEM, SEM-LFD) and atomic force microscopy (AFM). Moreover, the modified fabrics were subjected to analysis of elemental composition of the applied coatings using SEM-EDS techniques. Highly hydrophobic textiles were obtained in all cases studied and one of the modifications resulted in imparting superhydrophobic properties. Most of impregnated textiles remained hydrophobic even after multiple washing process which shows that the studied modification is durable.

  1. Fully Solution-Processable Fabrication of Multi-Layered Circuits on a Flexible Substrate Using Laser Processing

    Directory of Open Access Journals (Sweden)

    Seok Young Ji

    2018-02-01

    Full Text Available The development of printing technologies has enabled the realization of electric circuit fabrication on a flexible substrate. However, the current technique remains restricted to single-layer patterning. In this paper, we demonstrate a fully solution-processable patterning approach for multi-layer circuits using a combined method of laser sintering and ablation. Selective laser sintering of silver (Ag nanoparticle-based ink is applied to make conductive patterns on a heat-sensitive substrate and insulating layer. The laser beam path and irradiation fluence are controlled to create circuit patterns for flexible electronics. Microvia drilling using femtosecond laser through the polyvinylphenol-film insulating layer by laser ablation, as well as sequential coating of Ag ink and laser sintering, achieves an interlayer interconnection between multi-layer circuits. The dimension of microvia is determined by a sophisticated adjustment of the laser focal position and intensity. Based on these methods, a flexible electronic circuit with chip-size-package light-emitting diodes was successfully fabricated and demonstrated to have functional operations.

  2. Hybrid imprinting process to fabricate a multi-layer compound eye for multispectral imaging.

    Science.gov (United States)

    Chen, Jianwei; Lee, Hiu Hung; Wang, Dongping; Di, Si; Chen, Shih-Chi

    2017-02-20

    We present a high-precision hybrid imprinting method to fabricate multi-layer micro-optical structures on nonplanar substrates using a custom-built vacuum imprinting system; with the application of kinematic couplings that align the flexible stamps in all six degrees of freedom, a cross-layer pattern registration precision of 400 nm has been achieved on nonplanar substrates. To demonstrate the precision and feasibility of the new process and instrument, we have designed and fabricated a multi-layer artificial compound eye (ACE) for multispectral imaging. The shapes and sizes of all 12 micro-lenses on the ACE are optimized and integrated with different color filers (red, green and blue) so that the light from different channels and of different spectral contents will focus to the same plane, where the photodetector is located. Next, the multi-layer ACE is installed in a portable optical system for simultaneous multispectral imaging, i.e., to perform pattern detection by looking at specific frequency windows. Imaging experiments are devised and performed on (1) color blindness test cards, (2) space image, and (3) breast and gastric tumor samples. The results confirm the system's capabilities of frequency separation, extraction of hidden information, and tumor identification.

  3. Sub-micron period metal lattices fabricated by interfering ultraviolet femtosecond laser processing

    Science.gov (United States)

    Nakata, Yoshiki; Matsuba, Yoshiki; Miyanaga, Noriaki

    2016-05-01

    The interference pattern of a femtosecond laser has been utilized to fabricate nanostructures in the lattice. In this paper, SH (second-harmonic) waves (λ = 392.5 {{nm}}) of a femtosecond laser were applied to four beams interfering laser processing using a demagnification system as a beam correlator. The lattice constant of the resultant matrix was shortened to 760 nm. The unit structures fabricated on gold thin films were nanoholes, nanobumps, nanodrops or nanowhiskers, and their unit size was minimized compared to the case with a greater lattice constant formed by fundamental wavelengths. The radius of a nanoball on top of a nanodrop was between 42 and 76 nm, and the radius of metallic hole arrays (MHA) was 220 nm. The energy efficiency of the laser increased by 4.79 times due to better absorption coefficient of gold at ultraviolet wavelengths. In addition, the smallest lattice constant was estimated with the use of a commercial plano-convex fused-silica lens and a NIR (near-infrared) achromatic lens.

  4. Fabrication and Microstructure of Hydroxyapatite Coatings on Zirconia by Room Temperature Spray Process.

    Science.gov (United States)

    Seo, Dong Seok; Chae, Hak Cheol; Lee, Jong Kook

    2015-08-01

    Hydroxyapatite coatings were fabricated on zirconia substrates by a room temperature spray process and were investigated with regards to their microstructure, composition and dissolution in water. An initial hydroxyapatite powder was prepared by heat treatment of bovine-bone derived powder at 1100 °C for 2 h, while dense zirconia substrates were fabricated by pressing 3Y-TZP powder and sintering it at 1350 °C for 2 h. Room temperature spray coating was performed using a slit nozzle in a low pressure-chamber with a controlled coating time. The phase composition of the resultant hydroxyapatite coatings was similar to that of the starting powder, however, the grain size of the hydroxyapatite particles was reduced to about 100 nm due to their formation by particle impaction and fracture. All areas of the coating had a similar morphology, consisting of reticulated structure with a high surface roughness. The hydroxyapatite coating layer exhibited biostability in a stimulated body fluid, with no severe dissolution being observed during in vitro experimentation.

  5. Environmental psychology in the bioclimatic design; La psicologia ambiental en el diseno bioclimatico

    Energy Technology Data Exchange (ETDEWEB)

    Cubillas Talamante, Lorena Gpe [Facultad de Arquitectura, Universidad Autonoma de Baja California, Mexicali, Baja California (Mexico)

    2005-07-01

    The bioclimatic design profits of the natural resources for the improvement of the construction quality as well as the user's life. The combination of these two concepts within the architectonic design generates an interesting duality to consider within the understanding of the user's physical and psychological environment and the obtaining of a correlation of reality and dreams. Environmental psychology is focused on the researching of the psychological effects of the architectonic environment on the human experience and behavior. Human behavior works under parameters established during its development. Through the habits and styles of life practiced in childhood those parameters establish themselves to later on obtain satisfiers in the search of the life quality of human beings. [Spanish] El diseno bioclimatico aprovecha los recursos naturales para el mejoramiento de la calidad de la construccion y vida del usuario. La combinacion de estos dos conceptos dentro del diseno arquitectonico, genera dualidad interesante de entender el medio ambiente fisico y psicologico de los usuarios y obtener una identificacion entre la realidad y los suenos. La psicologia ambiental se ha enfocado a investigar sobre la relacion de los efectos psicologicos del ambiente construido o arquitectonico sobre la conducta y la experiencia humana. La conducta humana trabaja bajo parametros establecidos durante el desarrollo del mismo, a traves de los habitos y estilos de vida desde su infancia van marcando esos parametros que despues sirven para lograr satisfactores en la busqueda de la calidad de vida de los seres humanos.

  6. Design and fabrication of a glovebox for the Plasma Hearth Process radioactive bench-scale system

    International Nuclear Information System (INIS)

    Wahlquist, D.R.

    1996-01-01

    This paper presents some of the design considerations and fabrication techniques for building a glovebox for the Plasma Hearth Process (PHP) radioactive bench-scale system. The PHP radioactive bench-scale system uses a plasma torch to process a variety of radioactive materials into a final vitrified waste form. The processed waste will contain plutonium and trace amounts of other radioactive materials. The glovebox used in this system is located directly below the plasma chamber and is called the Hearth Handling Enclosure (HHE). The HHE is designed to maintain a confinement boundary between the processed waste and the operator. Operations that take place inside the HHE include raising and lowering the hearth using a hydraulic lift table, transporting the hearth within the HHE using an overhead monorail and hoist system, sampling and disassembly of the processed waste and hearth, weighing the hearth, rebuilding a hearth, and sampling HEPA filters. The PHP radioactive bench-scale system is located at the TREAT facility at Argonne National Laboratory-West in Idaho Falls, Idaho

  7. Adhesion enhancement between electroless nickel and polyester fabric by a palladium-free process

    Energy Technology Data Exchange (ETDEWEB)

    Lu Yinxiang, E-mail: yxlu@fudan.edu.cn [Department of Materials Science, Fudan University, 220 Handan Road, Shanghai 200433 (China); Xue Longlong; Li Feng [Department of Materials Science, Fudan University, 220 Handan Road, Shanghai 200433 (China)

    2011-01-15

    A new, efficient, palladium- and etchant-free process for the electroless nickel plating of poly(ethylene terephthalate) (PET) fabric has been developed. PET electroless plating can be prepared in three steps, namely: (i) the grafting of thiol group onto PET, (ii) the silver Ag{sup 0} seeding of the PET surface, and (iii) the nickel metallization using electroless plating bath. Scanning electron microscopy (SEM), energy dispersive X-ray (EDX) analysis, X-ray photoelectron spectroscopy (XPS), Raman spectrometer, X-ray diffraction (XRD), and thermogravimetric analysis (TG) were used to characterize the samples in the process, and the nickel loading was quantified by weighing. This process successfully compares with the traditional one based on KMnO{sub 4}/H{sub 2}SO{sub 4} etching and palladium-based seed layer. The nickel coating obtained in this palladium-free process can pass through ultrasonic washing challenge, and shows excellent adhesion with the PET substrate. However, the sample with Pd catalyst via traditional process was damaged during the testing experiment.

  8. CMOS compatible fabrication process of MEMS resonator for timing reference and sensing application

    Science.gov (United States)

    Huynh, Duc H.; Nguyen, Phuong D.; Nguyen, Thanh C.; Skafidas, Stan; Evans, Robin

    2015-12-01

    Frequency reference and timing control devices are ubiquitous in electronic applications. There is at least one resonator required for each of this device. Currently electromechanical resonators such as crystal resonator, ceramic resonator are the ultimate choices. This tendency will probably keep going for many more years. However, current market demands for small size, low power consumption, cheap and reliable products, has divulged many limitations of this type of resonators. They cannot be integrated into standard CMOS (Complement metaloxide- semiconductor) IC (Integrated Circuit) due to material and fabrication process incompatibility. Currently, these devices are off-chip and they require external circuitries to interface with the ICs. This configuration significantly increases the overall size and cost of the entire electronic system. In addition, extra external connection, especially at high frequency, will potentially create negative impacts on the performance of the entire system due to signal degradation and parasitic effects. Furthermore, due to off-chip packaging nature, these devices are quite expensive, particularly for high frequency and high quality factor devices. To address these issues, researchers have been intensively studying on an alternative for type of resonator by utilizing the new emerging MEMS (Micro-electro-mechanical systems) technology. Recent progress in this field has demonstrated a MEMS resonator with resonant frequency of 2.97 GHz and quality factor (measured in vacuum) of 42900. Despite this great achievement, this prototype is still far from being fully integrated into CMOS system due to incompatibility in fabrication process and its high series motional impedance. On the other hand, fully integrated MEMS resonator had been demonstrated but at lower frequency and quality factor. We propose a design and fabrication process for a low cost, high frequency and a high quality MEMS resonator, which can be integrated into a standard

  9. Electro-Physical Technique for Post-Fabrication Measurements of CMOS Process Layer Thicknesses.

    Science.gov (United States)

    Marshall, Janet C; Vernier, P Thomas

    2007-01-01

    This paper presents a combined physical and electrical post-fabrication method for determining the thicknesses of the various layers in a commercial 1.5 μm complementary-metal-oxide-semiconductor (CMOS) foundry process available through MOSIS. Forty-two thickness values are obtained from physical step-height measurements performed on thickness test structures and from electrical measurements of capacitances, sheet resistances, and resistivities. Appropriate expressions, numeric values, and uncertainties for each layer of thickness are presented, along with a systematic nomenclature for interconnect and dielectric thicknesses. However, apparent inconsistencies between several of the physical and electrical results for film thickness suggest that further uncertainty analysis is required and the effects of several assumptions need to be quantified.

  10. Fabrication of Carbon Nanofibers/A356 Nanocomposites by High-Intensity Ultrasonic Processing

    Science.gov (United States)

    Wu, Qing-Jie; Yan, Hong

    2018-03-01

    A356 alloy reinforced with carbon nanofibers (CNFs) was fabricated by high-intensity ultrasonic vibration processing. The microstructure and mechanical properties were investigated. The distribution of CNFs became more and more uniform with the increase of ultrasonic power, and the mechanical properties of nanocomposites were significantly enhanced accordingly. The yield strength (YS), ultimate tensile strength (UTS), and microhardness of the nanocomposite increased by 38.3, 21.9, and 43.2 pct, respectively, at a CNF content of 0.9 wt pct compared with the matrix without CNF addition. The improvement in mechanical properties was the effect of CNFs on the thermal expansion mismatch strengthening of the nanocomposite, the grain refinement of the nanocomposite, and the load transfer from the matrix to the nanofibers.

  11. Optimizing the fabrication process of a high-efficiency blazed grating through diamond scribing and molding

    International Nuclear Information System (INIS)

    Lee, ChaBum; Woo, Do-Kyun; Lee, Sun-Kyu; Kuriyagawa, Tsunemoto

    2010-01-01

    This paper presents the experimental investigation of an optimal hot embossing process to prevent the nanoscale thermal deformation of microstructures replicated from the electroless Ni mold fabricated by the diamond tool-interfered scribing method. A polymer-based PMMA was replicated from the mold with the blazed profile: period 2.0 µm and depth 0.2 µm. The molding conditions, the applying pressure (P m ), molding temperature (T m ) and demolding temperature (T d ) were chosen as experiment parameters. In terms of the quality of surface smoothness, profile, sharp edge, surface roughness and optical performance of the replica, the conditions, P m = 0.9 MPa, T m = 150 °C and T d = 20 °C, showed a best results. From optical testing, diffraction efficiency of the replica was measured, 87.6%, and the replica molded in other conditions showed a noticeable efficiency drop due to the molding error.

  12. Height Control and Deposition Measurement for the Electron Beam Free Form Fabrication (EBF3) Process

    Science.gov (United States)

    Seufzer, William J. (Inventor); Hafley, Robert A. (Inventor)

    2017-01-01

    A method of controlling a height of an electron beam gun and wire feeder during an electron freeform fabrication process includes utilizing a camera to generate an image of the molten pool of material. The image generated by the camera is utilized to determine a measured height of the electron beam gun relative to the surface of the molten pool. The method further includes ensuring that the measured height is within the range of acceptable heights of the electron beam gun relative to the surface of the molten pool. The present invention also provides for measuring a height of a solid metal deposit formed upon cooling of a molten pool. The height of a single point can be measured, or a plurality of points can be measured to provide 2D or 3D surface height measurements.

  13. Fabrication of superhydrophobic wood surfaces via a solution-immersion process

    Science.gov (United States)

    Liu, Changyu; Wang, Shuliang; Shi, Junyou; Wang, Chengyu

    2011-11-01

    Superhydrophobic wood surfaces were fabricated from potassium methyl siliconate (PMS) through a convenient solution-immersion method. The reaction involves a hydrogen bond assembly and a polycondensation process. The silanol was formed by reacting PMS aqueous solution with CO2, which was assembled on the wood surface via hydrogen bonds with the wood surface -OH groups. The polymethylsilsesquioxane coating was obtained through the polycondensation reaction of the hydroxyl between wood and silanol. The morphology of products were characterized using a scanning electron microscope (SEM), the surface chemical composition was determined using energy dispersive X-ray analysis (EDXA), Fourier transform infrared spectroscopy (FT-IR), thermogravimetry (TGA) and contact angle measurement. Analytical results revealed that rough protuberances uniformly covered the wood surface, thus transforming the wood surface from hydrophilic to superhydrophobic. The water contact angle of the superhydrophobic wood surface was about 153° and a sliding angle was 4.6°.

  14. Tunable biphasic drug release from ethyl cellulose nanofibers fabricated using a modified coaxial electrospinning process

    Science.gov (United States)

    2014-01-01

    This manuscript reports a new type of drug-loaded core-shell nanofibers that provide tunable biphasic release of quercetin. The nanofibers were fabricated using a modified coaxial electrospinning process, in which a polyvinyl chloride (PVC)-coated concentric spinneret was employed. Poly (vinyl pyrrolidone) (PVP) and ethyl cellulose (EC) were used as the polymer matrices to form the shell and core parts of the nanofibers, respectively. Scanning and transmission electron microscopy demonstrated that the nanofibers had linear morphologies and core-shell structures. The quercetin was found to be present in the nanofibers in the amorphous physical status, on the basis of X-ray diffraction results. In vitro release profiles showed that the PVP shell very rapidly freed its drug cargo into the solution, while the EC core provided the succedent sustained release. Variation of the drug loading permitted the release profiles to be tuned. PMID:24940180

  15. Alternative Post-Processing on a CMOS Chip to Fabricate a Planar Microelectrode Array

    Science.gov (United States)

    López-Huerta, Francisco; Herrera-May, Agustín L.; Estrada-López, Johan J.; Zuñiga-Islas, Carlos; Cervantes-Sanchez, Blanca; Soto, Enrique; Soto-Cruz, Blanca S.

    2011-01-01

    We present an alternative post-processing on a CMOS chip to release a planar microelectrode array (pMEA) integrated with its signal readout circuit, which can be used for monitoring the neuronal activity of vestibular ganglion neurons in newborn Wistar strain rats. This chip is fabricated through a 0.6 μm CMOS standard process and it has 12 pMEA through a 4 × 3 electrodes matrix. The alternative CMOS post-process includes the development of masks to protect the readout circuit and the power supply pads. A wet etching process eliminates the aluminum located on the surface of the p+-type silicon. This silicon is used as transducer for recording the neuronal activity and as interface between the readout circuit and neurons. The readout circuit is composed of an amplifier and tunable bandpass filter, which is placed on a 0.015 mm2 silicon area. The tunable bandpass filter has a bandwidth of 98 kHz and a common mode rejection ratio (CMRR) of 87 dB. These characteristics of the readout circuit are appropriate for neuronal recording applications. PMID:22346681

  16. Study on properties of CFRP fabricated by VA-RTM process

    Science.gov (United States)

    Jeoung, Sun Kyoung; Hwang, Ye Jin; Lee, Hyun Wook; Son, Soon Keun; Kim, Hyung Sik; Ha, Jin Uk

    2016-03-01

    Carbon fiber reinforced plastics (CFRP) have a lot of attention from industry and academia due to its excellent mechanical property. It has been used for aircraft, automotive and so on, since it can replace metallic materials and reduce total weight with increased physical properties. However, the manufacturing process and the material cost are still challenging to be commercialized in the automotive market. Therefore, many researchers are trying to minimize materials and process cost for broadening their applications. In this study, thermoset epoxy resins were used for binder of CFRP. Epoxy resins were investigated in order to figure out optimized curing speed under vacuum assisted resin transfer molding (VARTM) processing condition. Mechanical properties of CFRP with different carbon fiber orientation and woven carbon fiber were compared to mathematically simulated results. In order to develop the application of automobile component, reliability tests of CFRP were carried out. Tensile strength of CFRP is increased when the orientation angle between fiber and axis of load was decreased (90°→ 0°). It is considered that epoxy and carbon fiber absorbed the tensile energy because the orientation of fiber and the load bearing are matched with axis direction. In addition, the CFRP automobile engine hood was fabricated by VARTM process. Drop weight impact tests (20kg & 100kg weight) were carried out in order to simulate crash performance of CFRP engine hoods.

  17. Fabrication of protein microarrays for alpha fetoprotein detection by using a rapid photo-immobilization process

    Directory of Open Access Journals (Sweden)

    Sirasa Yodmongkol

    2016-03-01

    Full Text Available In this study, protein microarrays based on sandwich immunoassays are generated to quantify the amount of alpha fetoprotein (AFP in blood serum. For chip generation a mixture of capture antibody and a photoactive copolymer consisting of N,N-dimethylacrylamide (DMAA, methacryloyloxy benzophenone (MaBP, and Na-4-styrenesulfonate (SSNa was spotted onto unmodified polymethyl methacrylate (PMMA substrates. Subsequently to printing of the microarray, the polymer and protein were photochemically cross-linked and the forming, biofunctionalized hydrogels simultaneously bound to the chip surface by short UV- irradiation. The obtained biochip was incubated with AFP antigen, followed by biotinylated AFP antibody and streptavidin-Cy5 and the fluorescence signal read-out. The developed microarray biochip covers the range of AFP in serum samples such as maternal serum in the range of 5 and 100 ng/ml. The chip production process is based on a fast and simple immobilization process, which can be applied to conventional plastic surfaces. Therefore, this protein microarray production process is a promising method to fabricate biochips for AFP screening processes. Keywords: Photo-immobilization, Protein microarray, Alpha fetoprotein, Hydrogel, 3D surface, Down syndrome

  18. Cellulose based cationic adsorbent fabricated via radiation grafting process for treatment of dyes waste water.

    Science.gov (United States)

    Goel, Narender Kumar; Kumar, Virendra; Misra, Nilanjal; Varshney, Lalit

    2015-11-05

    A cationized adsorbent was prepared from cellulosic cotton fabric waste via a single step-green-radiation grafting process using gamma radiation source, wherein poly[2-(methacryloyloxy) ethyl]trimethylammonium chloride (PMAETC) was covalently attached to cotton cellulose substrate. Radiation grafted (PMAETC-g-cellulose) adsorbent was investigated for removal of acid dyes from aqueous solutions using two model dyes: Acid Blue 25 (AB25) and Acid Blue 74 (AB74). The equilibrium adsorption data was analyzed by Langmuir and Freundlich isotherms, whereas kinetic data was analyzed by pseudo first order, pseudo second order, intra particle diffusion and Boyd's models. The PMAETC-g-cellulose adsorbent with 25% grafting yield exhibited equilibrium adsorption capacities of ∼ 540.0mg/g and ∼ 340.0mg/g for AB25 and AB74, respectively. Linear and nonlinear fitting of adsorption data suggested that the equilibrium adsorption process followed Langmuir adsorption isotherm model, whereas, the kinetic adsorption process followed pseudo-second order model. The multi-linearities observed in the intra-particle kinetic plots suggested that the intraparticle diffusion was not the only rate-controlling process in the adsorption of acid dyes on the adsorbent, which was further supported by Boyd's model. The adsorbent could be regenerated by eluting the adsorbed dye from the adsorbent and could be repeatedly used. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Fabrication of Surface Level Cu/Si Cp Nano composites by Friction Stir Processing Route

    International Nuclear Information System (INIS)

    Srinivasan, R. C.; Karunanithi, M.

    2015-01-01

    Friction stir processing (FSP) technique has been successfully employed as low energy consumption route to prepare copper based surface level nano composites reinforced with nano sized silicon carbide particles (Si Cp). The effect of FSP parameters such as tool rotational speed, processing speed, and tool tilt angle on microstructure and microhardness was investigated. Single pass FSP was performed based on Box-Behnken design at three factors in three levels. A cluster of blind holes 2 mm in diameter and 3 mm in depth was used as particulate deposition technique in order to reduce the agglomeration problem during composite fabrication. K-type thermocouples were used to measure temperature histories during FSP. The results suggest that the heat generation during FSP plays a significant role in deciding the microstructure and microhardness of the surface composites. Microstructural observations revealed a uniform dispersion of nano sized Si Cp without any agglomeration problem and well bonded with copper matrix at different process parameter combinations. X-ray diffraction study shows that no intermetallic compound was produced after processing. The microhardness of nano composites was remarkably enhanced and about 95% more than that of copper matrix

  20. Fabrication of Surface Level Cu/SiCp Nanocomposites by Friction Stir Processing Route

    Directory of Open Access Journals (Sweden)

    Cartigueyen Srinivasan

    2015-01-01

    Full Text Available Friction stir processing (FSP technique has been successfully employed as low energy consumption route to prepare copper based surface level nanocomposites reinforced with nanosized silicon carbide particles (SiCp. The effect of FSP parameters such as tool rotational speed, processing speed, and tool tilt angle on microstructure and microhardness was investigated. Single pass FSP was performed based on Box-Behnken design at three factors in three levels. A cluster of blind holes 2 mm in diameter and 3 mm in depth was used as particulate deposition technique in order to reduce the agglomeration problem during composite fabrication. K-type thermocouples were used to measure temperature histories during FSP. The results suggest that the heat generation during FSP plays a significant role in deciding the microstructure and microhardness of the surface composites. Microstructural observations revealed a uniform dispersion of nanosized SiCp without any agglomeration problem and well bonded with copper matrix at different process parameter combinations. X-ray diffraction study shows that no intermetallic compound was produced after processing. The microhardness of nanocomposites was remarkably enhanced and about 95% more than that of copper matrix.

  1. Consumable Process Development for Chemical Mechanical Planarization of Bit Patterned Media for Magnetic Storage Fabrication

    Science.gov (United States)

    Bonivel, Joseph T., Jr.

    2010-09-01

    As the superparamagnetic limit is reached, the magnetic storage industry looks to circumvent the barrier by implementing patterned media (PM) as a viable means to store and access data. Chemical mechanical polishing (CMP) is a semiconductor fabrication technique used to planarize surfaces and is investigated as a method to ensure that the PM is polished to surface roughness parameters that allow the magnetic read/write head to move seamlessly across the PM. Results from this research have implications in feasibility studies of utilizing CMP as the main planarization technique for PM fabrication. Benchmark data on the output parameters of the CMP process, for bit patterned media (BPM), based on the machine process parameters, pad properties, and slurry characteristics are optimized. The research was conducted in a systematic manner in which the optimized parameters for each phase are utilized in future phases. The optimum results from each of the phases provide an overall optimum characterization for BPM CMP. Results on the CMP machine input parameters indicate that for optimal surface roughness and material removal, low polish pressures and high velocities should be used on the BPM. Pad characteristics were monitored by non destructive technique and results indicate much faster deterioration of all padcharacteristics versus polish time of BPM when compared to IC CMP. The optimum pad for PM polishing was the IC 1400 dual layer Suba V pad with a shore hardness of 57, and a k-groove pattern. The final phase of polishing evaluated the slurry polishing properties and novel nanodiamond (ND) slurry was created and benchmarked on BPM. The resulting CMP output parameters were monitored and neither the ND slurry nor the thermally responsive polymer slurry performed better than the commercially available Cabot iCue slurry for MRR or surface roughness. Research results indicate CMP is a feasible planarization technique for PM fabrication, but successful implementation of CMP

  2. On-Demand Gas-to-Liquid Process To Fabricate Thermoresponsive Antimicrobial Nanocomposites and Coatings.

    Science.gov (United States)

    Poudel, Bijay Kumar; Park, Jae Hong; Byeon, Jeong Hoon

    2017-05-10

    Antimicrobial material is emerging as a major component of the mitigation strategy against microbial growth on abiotic surfaces. In this work, a newly designed process is proposed to fabricate thermoresponsive antimicrobial nanocomposites (TANs) and coatings (TACs) as an on-demand system. Thermoresponsive polymer (TRP)-incorporated silver (Ag) nanocomposites with silica nanoparticles (SNPs) or carbon nanotubes (CNTs; Ag-SNP@TRP or Ag-CNT@TRP) were produced by a single-pass gas-to-liquid process. The SNPs or CNTs were first produced by spark ablation and successively injected for dispersal in a liquid cell containing polydimethylsiloxane, poly(N-isopropylacrylamide), and silver nitrate under ultrasound irradiation. Suspensions of Ag-SNP@TRP or Ag-CNT@TRP nanocomposites were then deposited on a touch screen panel (TSP) protection film via electrohydrodynamic spray to form transparent antibacterial coatings. Fundamental antibacterial activities of TANs were evaluated against Escherichia coli and Staphylococcus epidermidis. The TANs showed stronger antibacterial activities at the higher temperature for all testing conditions. Lower minimum inhibitory concentrations of Ag-SNP@TRP and Ag-CNT@TRP nanocomposites were required against the two bacteria at 37 °C compared to those at 27 °C. The TACs on display showed elevated antimicrobial activity when the panel was turned on (38.1 °C) compared with when the panel was turned off (23.8 °C). This work provides a utilizable concept to continuously fabricate TANs and TACs, and it specifically offers stimuli-sensitive control of antimicrobial activity on TSPs, including other frequently touched surfaces.

  3. Design and fabrication of a 30 T superconducting solenoid using overpressure processed Bi2212 round wire

    Energy Technology Data Exchange (ETDEWEB)

    Flanagan, Gene [Muons, Inc., Batavia, IL (United States); Johnson, Rolland [Muons, Inc., Batavia, IL (United States)

    2016-02-18

    High field superconducting magnets are used in particle colliders, fusion energy devices, and spectrometers for medical imaging and advanced materials research. Magnets capable of generating fields of 20-30 T are needed by future accelerator facilities. A 20-30 T magnet will require the use of high-temperature superconductors (HTS) and therefore the challenges of high field HTS magnet development need to be addressed. Superconducting Bi2Sr2CaCu2Ox (Bi2212) conductors fabricated by the oxide-powder-in-tube (OPIT) technique have demonstrated the capability to carry large critical current density of 105 A/cm2 at 4.2 K and in magnetic fields up to 45 T. Available in round wire multi-filamentary form, Bi2212 may allow fabrication of 20-50 T superconducting magnets. Until recently the performance of Bi2212 has been limited by challenges in realizing high current densities (Jc ) in long lengths. This problem now is solved by the National High Magnetic Field Lab using an overpressure (OP) processing technique, which uses external pressure to process the conductor. OP processing also helps remove the ceramic leakage that results when Bi-2212 liquid leaks out from the sheath material and reacts with insulation, coil forms, and flanges. Significant advances have also been achieved in developing novel insulation materials (TiO2 coating) and Ag-Al sheath materials that have higher mechanical strengths than Ag-0.2wt.% Mg, developing heat treatment approaches to broadening the maximum process temperature window, and developing high-strength, mechanical reinforced Bi-2212 cables. In the Phase I work, we leveraged these new opportunities to prototype overpressure processed solenoids and test them in background fields of up to 14 T. Additionally a design of a fully superconducting 30 T solenoid was produced. This work in conjunction with the future path outlined in the Phase II proposal would

  4. A novel surface micromachining process to fabricate AlN unimorph suspensions and its application for RF resonators

    NARCIS (Netherlands)

    Saravanan, S.; Saravanan, S.; Berenschot, Johan W.; Krijnen, Gijsbertus J.M.; Elwenspoek, Michael Curt

    2006-01-01

    A novel surface micromachining process is reported for aluminum nitride (AlN) thin films to fabricate piezoelectric unimorph suspension devices for micro actuator applications. Wet anisotropic etching of AlN thin film is used with a Cr metal mask layer in the microfabrication process. Tetra methyl

  5. Fabrication process for tall, sharp, hollow, high aspect ratio polymer microneedles on a platform

    International Nuclear Information System (INIS)

    Ceyssens, Frederik; Chaudhri, Buddhadev Paul; Van Hoof, Chris; Puers, Robert

    2013-01-01

    This paper reports on a new lithographic process for fabricating arrays of tall, high aspect ratio (defined as height/wall thickness), hollow, polymer microneedles on a platform. The microneedles feature a high sharpness (down to 3 µm tip radius) and aspect ratio (>65) which is a factor 2 and 4 better than the state of the art, respectively. The maximum achievable needle shaft length is over 1 mm. The improved performance was obtained by using an anisotropically patterned silicon substrate covered with an antireflective layer as mold for the needle tip and an optimized SU-8 lithographic process. Furthermore, a platform containing liquid feedthroughs holding an arbitrary number of needles out of plane can be manufactured with only one additional process step. The high aspect ratio microneedles undergo failure at the critical load of around 230 mN in the case of 1 mm long hollow needles with triangular cross section and a base of 175 µm. Penetration into human skin is demonstrated as well. (paper)

  6. A novel filtration method for cord blood processing using a polyester fabric filter.

    Science.gov (United States)

    Shima, T; Forraz, N; Sato, N; Yamauchi, T; Iwasaki, H; Takenaka, K; Akashi, K; McGuckin, C; Teshima, T

    2013-08-01

    Cord blood (CB) is being increasingly used as a source of hematopoietic stem cells for transplantation to treat diseases of the blood and immune systems, and there is an urgent need to expand CB banking worldwide. CB processing requires costly machinery or a clean room that hampers wider application of CBT particularly in the developing countries. We developed a novel filtration system using a nonchemical-coated and nonwoven polyester fabric filter, which traps cells through affinity and does not require centrifugation or potentially toxic chemicals. Cell processing with the device resulted in minimum cell loss of total cells and CD34⁺ cells, without impairing the ability of CD34⁺ cells to engraft and differentiate both in vivo and in vitro. CB processing with this device is simple, cost-effective, and nontoxic without requiring costly equipment will thus facilitate international CB banking, which helps in meeting the increasing worldwide demand for CB for allogeneic hematopoietic stem cell transplantation. © 2012 John Wiley & Sons Ltd.

  7. Ergonomic Design Measures on Work Process and Workplace Layout in the Selected Structural and Fabrication Shops

    Directory of Open Access Journals (Sweden)

    Suzette M. Mercado

    2015-11-01

    Full Text Available The study aimed to analyze the process and workplace layout in the selected structural and fabrication shops located in Batangas, Philippines thus provide improvements using the results of Ergonomic Design Measures. These shops generally focused on preparation, cutting, welding, grinding and assembly using multi-functioning machines and many aspects of human work. Using different Ergonomic Assessment Checklist, Rapid Entire Body Assessment (REBA, Rapid Upper Limb Assessment (RULA and Ovako Working Posture Assessment System (OWAS, and with direct observations, it was found out that existing design of the work processes and workplace layout does not match the ergonomic requirements. The study exposed the presence of Musculoskeletal Disorder (MSD risks due to awkward posture, forceful exertion and fatigue; position of workers is dangerous to themselves due to inappropriate measurement of facilities which is in need of change. The researcher recommended ergonomically based actions to address the health, comfort, and well-being of employees such as changing the workstation surface height, integration of safeguarding; application of Group Technology to reduce the production lead time and material handling and offered smooth workflow in production line. Furthermore, the researcher developed a proposed workstation and workplace design as part of the ergonomic-based actions. The effectiveness of the proposed design alternatives were measured with the use of Trade-off Analysis technique, such as, Standard Weighted Sum Method, MAXIMIN decision and Analytic Hierarchy Process.

  8. Combined Macroscopic and Microscopic Thermo-Elasto-Plastic Stresses of Functionally Graded Palte Considering Fabrication Process

    Science.gov (United States)

    Shabana, Yasser Mohamed; Noda, Naotake; Tohgo, Keiichiro

    Functionally Graded Material (FGM) is a heterogeneous composite material that consists of a gradient compositional variation of the constituent materials from one surface of the material to the other. These continuous changes result in gradient material properties. Since ceramic has good heat resistance and metal has high strength, FGM made by ceramic and metal can work at super high temperatures or under a high-temperature-difference field. It is a primary to reduce thermal stress by selection of different effective material properties for the intermediate composition of the EGM and to prevent destruction by thermal stress. FGM is manufactured at a high temperature and then residual thermal stresses are produced during cooling to room temperature. In this paper, the elastic-plastic thermal stresses induced in a ceramic-metal FGM plate (FGP) taking the fabrication process into consideration are discussed. The region near the heat resistant surface is produced by metal particle reinforced ceramic while the region near the cooling surface is vice versa. As the metal and the ceramic near the middle region of the FGM are perfectly mixed, it is impossible to consider the particle-reinforced material. In this study, the FGP is divided into three regions. First, the region near the cooling surface is metal rich and then the metal is considered as a matrix while the ceramic is considered as particles. Second, the region near the heat resistant surface is ceramic rich so that the ceramic is considered as a matrix while the metal is considered as particles. Third, in the middle part between the previous two regions the metal and ceramic are perfectly mixed. In the third region macroscopic analysis is considered because the difference between the volume fractions of the ceramic and the metal is small and it is difficult to consider one of them as a matrix or particles. The effects of the distribution parameter of the composition and the fabrication temperature on the thermal

  9. Density match during fabrication process of poly (α-methylstyrene) mandrels by microencapsulation

    International Nuclear Information System (INIS)

    Chen Sufen; Su Lin; Liu Yiyang; Li Bo; Qi Xiaobo; Zhang Zhanwen; Liu Meifang

    2012-01-01

    During the curing process of double emulsions for fabricating poly (α-methylstyrene) (PAMS) capsules by microencapsulation technology, the match of density between the water in oil compound droplet and the outer water phase is vital to the sphericity of PAMS capsules. To investigate the effects of density mismatch on the sphericity of the resulting PAMS capsules, the densities of compound droplets with different inner diameters and polymer oil layer thicknesses were calculated theoretically and measured experimentally during the curing process. Also, the polymer concentrations of the oil phase in the compound droplets during the curing process were further studied. The results show that, the density mismatch between the compound droplets and the outer water phase can be quantitatively controlled by adjusting the compositions of the outer water phase. The curing stage with the polymer concentration of the oil phase increasing from 20% to 60% is the key phase of the curing process. When the density mismatch between the compound droplets and the outer water phase lowering from 0.00495 g/cm 3 to 0.00002 g/cm 3 , the number percentage of PAMS capsules with out of round (OOR) value less than 10 μm in batches can be increased from 14.3% to 93.3%. Thus for the compound droplets with different inner diameters and polymer oil layer thicknesses, the sphericity of the resulting PAMS capsules can be significantly improved, through reducing the density mismatch between the compound droplets and the outer water phase in the key phase of the curing process. (authors)

  10. Protective Coatings for Space System Components Fabricated Using Ionic Self Assembled Monolayer Processes

    National Research Council Canada - National Science Library

    Miler, Mike

    1997-01-01

    Self-assembled multilayer thin film fabrication methods offer unique opportunities to incorporate multiple functionalities into coatings for space system materials and structures as well as consumer products...

  11. Cost-benefit of energy saving in bioclimatic designs; Costo-beneficio del ahorro de energia en los disenos bioclimatios

    Energy Technology Data Exchange (ETDEWEB)

    Lopez P, J. Manuel A. [Doble dos soluciones de Negocios (Mexico); Morillon G, David; Rdriguez V, Luis [Universidad Autonoma de Mexico (Mexico)

    2001-06-01

    Tools and criteria for Cost-Benefit Analysis (ACB) of energy saving in bioclimatic designs (DB) are presented, for which a reference project is established. Based on the traditional design of air conditioning of a building and with the support of this one, the estimation of costs and benefits of the same building is made; but with passive systems. The tools used consider related resources such as time and money. Criteria are used such as: Present value (VP), Equivalent Annual Cost (EAC) and the Cost of the conserved Energy (CEC). The costs related to the construction, maintenance and operation of the design are taken into consideration. The differences between the design of reference and the Bioclimatic Design, established from the application of these criteria, allow evaluating the economic margin as far as operation and maintenance. Finally, the cost of the conserved energy of the bioclimatic measures is evaluated as an initiative for energy saving and calculates the present value from them in all of the period of useful life of the bioclimatic design. [Spanish] Se presentan herramientas y criterios para el analisis Costo-Beneficio (ACB) del ahorro de energia en los disenos bioclimaticos (DB), para lo cual se establece un proyecto de referencia. Basado en el diseno tradicional de la climatizacion de un edificio y con apoyo en este, se realiza la estimacion de costos y beneficios del mismo edificio; pero con sistema pasivos. Las herramientas usadas consideran recursos relacionados como son tiempo y dinero. Se usan criterios tales como: Valor Presente (VP), Costo Anual Equivalente (CAE) y el Costo de la Energia conservada (CEC). Se toman en consideracion los costos relacionados con la construccion, mantenimiento y operacion del diseno. Las diferencias entre el diseno de referencia y el Diseno Bioclimatico, establecidas a partir de la aplicacion de estos criterios, permiten evaluar el margen economico en cuanto a la operacion y el mantenimiento. Finalmente, se

  12. Binder Jetting: A Novel NdFeB Bonded Magnet Fabrication Process

    Science.gov (United States)

    Paranthaman, M. Parans; Shafer, Christopher S.; Elliott, Amy M.; Siddel, Derek H.; McGuire, Michael A.; Springfield, Robert M.; Martin, Josh; Fredette, Robert; Ormerod, John

    2016-07-01

    The goal of this research is to fabricate near-net-shape isotropic (Nd)2Fe14B-based (NdFeB) bonded magnets using a three dimensional printing process to compete with conventional injection molding techniques used for bonded magnets. Additive manufacturing minimizes the waste of critical materials and allows for the creation of complex shapes and sizes. The binder jetting process works similarly to an inkjet printer. A print-head passes over a bed of NdFeB powder and deposits a polymer binding agent to bind the layer of particles together. The bound powder is then coated with another layer of powder, building the desired shape in successive layers of bonded powder. Upon completion, the green part and surrounding powders are placed in an oven at temperatures between 100°C and 150°C for 4-6 h to cure the binder. After curing, the excess powder can be brushed away to reveal the completed "green" part. Green magnet parts were then infiltrated with a clear urethane resin to achieve the measured density of the magnet of 3.47 g/cm3 close to 46% relative to the NdFeB single crystal density of 7.6 g/cm3. Magnetic measurements indicate that there is no degradation in the magnetic properties. This study provides a new pathway for preparing near-net-shape bonded magnets for various magnetic applications.

  13. Fabrication of biomimetic hydrophobic films with corrosion resistance on magnesium alloy by immersion process

    International Nuclear Information System (INIS)

    Liu Yan; Lu Guolong; Liu Jindan; Han Zhiwu; Liu Zhenning

    2013-01-01

    Highlights: ► We have developed a facile and simple method of creating a hydrophobic surface on a magnesium alloy by an immersion process at room temperature. ► The distribution of the micro-structure and the roughness of the surface play critical roles in transforming from hydrophilic to hydrophobic. ► The hydrophobic coatings possess better corrosion resistance than magnesium alloy matrix. - Abstract: Biomimetic hydrophobic films of crystalline CeO 2 were prepared on magnesium alloy by an immersion process with cerium nitrate solution and then modified with DTS (CH 3 (CH 2 ) 11 Si(OCH 3 ) 3 ). The CeO 2 films fabricated with 20-min immersion yield a water contact angle of 137.5 ± 2°, while 20-min DTS treatment on top of CeO 2 can further enhance the water contact angle to 146.7 ± 2°. Then corrosion-resistant property of these prepared films against NaCl solution was investigated and elucidated using electrochemical measurements.

  14. Fabrication of Fe-Cr-Mo powder metallurgy steel via a mechanical-alloying process

    Science.gov (United States)

    Park, Jooyoung; Jeong, Gowoon; Kang, Singon; Lee, Seok-Jae; Choi, Hyunjoo

    2015-11-01

    In this study, we employed a mechanical-alloying process to manufacture low-alloy CrL and CrM steel powders that have similar specifications to their water-atomized counterparts. X-ray diffraction showed that Mo and Cr are alloyed in Fe after four cycles of planetary milling for 1 h at 150 RPM with 15-min pauses between the cycles (designated as P2C4 process). Furthermore, the measured powder size was found to be similar to that of the water-atomized counterparts according to both scanning electron microscope images and laser particle size analysis. The samples were sintered at 1120 °C, after which the P2C4-milled CrL showed similar hardness to that of water-atomized CrL, whereas the P2C4-milled CrM showed about 45% lower hardness than that of its water-atomized counterpart. Water-atomized CrM consists of a well-developed lathtype microstructure (bainite or martensite), while a higher fraction of polygonal ferrite is observed in P2C4-milled CrM. This phase difference causes the reduction of hardness in the P2C4-milled CrM, implying that the phase transformation behavior of specimens produced via powder metallurgy is influenced by the powder fabrication method.

  15. Fabrication of UO/sub 2/ microspheres by the hydrolysis process

    Energy Technology Data Exchange (ETDEWEB)

    Abdel-Halim, A.S.; Afifi, Y.K.; El-Adham, K.A.

    1987-10-01

    The application of the hydrolysis process to the fabrication of UO/sub 2/ microspheres is described. The process consists of successive steps, such as feed preparation, drop formation and gelation, washing and soaking, drying, reduction and sintering. The effect of washing and soaking conditions on the properties of UO/sub 2/ gel microspheres was investigated. The influence of reduction conditions, such as H/sub 2/ or NH/sub 3/ atmosphere and temperature, on the reduced density of UO/sub 2/ microspheres was studied. The sintering behaviour of UO/sub 2/ microspheres prepared under different conditions of washing and soaking was studied in an atmosphere of Ar or NH/sub 3/ at relatively low temperatures (1100...1400/sup 0/C). It was found that washing with ammonia solution and soaking in ammonia solution before washing result in good sinterable microspheres with a high specific surface area (10...12 m/sup 2//g) and small crystallite size (85...110 A). Dense UO/sub 2/ microspheres (> 95% th.d.) can be prepared by sintering in Ar at 1100/sup 0/C for 2 h.

  16. High Temperature Oxidation Property of SiC Coating Layer Fabricated by Aerosol Deposition Process

    Directory of Open Access Journals (Sweden)

    Ham G.-S.

    2017-06-01

    Full Text Available This study investigated the high temperature oxidation property of SiC coated layer fabricated by aerosol deposition process. SiC coated layer could be successfully manufactured by using pure SiC powders and aerosol deposition on the Zr based alloy in an optimal process condition. The thickness of manufactured SiC coated layer was measured about 5 μm, and coating layer represented high density structure. SiC coated layer consisted of α-SiC and β-SiC phases, the same as the initial powder. The initial powder was shown to have been crushed to the extent and was deposited in the form of extremely fine particles. To examine the high temperature oxidation properties, oxidized weight gain was obtained for one hour at 1000°C by using TGA. The SiC coated layer showed superior oxidation resistance property than that of Zr alloy (substrate. The high temperature oxidation mechanism of SiC coated layer on Zr alloy was suggested. And then, the application of aerosol deposited SiC coated layer was also discussed.

  17. Effects of heat treatment process for blanket fabrication on mechanical properties of F82H

    International Nuclear Information System (INIS)

    Hirose, T.; Shiba, K.; Sawai, T.; Jitsukawa, S.; Akiba, M.

    2004-01-01

    The objectives of this work are to evaluate the effects of thermal history corresponding to a blanket fabrication process on Reduced Activation Ferritic/Martensitic steel (RAF/Ms) microstructure, and to establish appropriate Hot Isostatic Pressing (HIP) conditions without degradation in the microstructures. One of RAF/Ms F82H and its modified versions were investigated by metallurgical methods after isochronal heat treatments up to 1473 K simulating HIP thermal history. Although conventional F82H showed significant grain growth after conventional solid HIP conditions, F82H with 0.1 wt% tantalum maintained a fine grain structure after the same heat treatment. It is considered that the grain coarsening was caused by dissolution of tantalum-carbide which immobilizes grain boundaries. On the other hands, conventional RAF/Ms with coarse grains were recovered by post HIP normalizing at temperatures below the TaC solvus temperature. This process can refine the grain size of F82H to more than ASTM grain size number 7

  18. Critical current property in YBCO coated conductor fabricated by improved TFA-MOD process

    Energy Technology Data Exchange (ETDEWEB)

    Inoue, M., E-mail: inoue@ees.kyushu-u.ac.j [Department of EESE, Kyushu University, Moto-oka 744, NIshi-ku, Fukuoka 819-0395 (Japan); Kiss, T.; Motoyama, K. [Department of EESE, Kyushu University, Moto-oka 744, NIshi-ku, Fukuoka 819-0395 (Japan); Awaji, S.; Watanabe, K. [Institute for Materials, Tohoku University, Sendai 980-8577 (Japan); Yoshizumi, M.; Yamada, Y.; Izumi, T.; Shiohara, Y. [Superconductivity Research Laboratory, Tokyo 135-0062 (Japan)

    2009-10-15

    We have investigated critical current property in YBa{sub 2}Cu{sub 3}O{sub 7-d}elta (YBCO) coated conductor fabricated by improved metal organic deposition using trifluoroacetates (TFA-MOD) process optimizing conditions such as solution compositions. The electric field vs. current density (E-J) characteristic measurement was carried out at wide range of temperature, T, and magnetic field, B. Critical current density, J{sub c}, reached 3.8 x 10{sup 10} A/m{sup 2} at 77 K in self-field for 1.2 mum thick YBCO layer. In-field J{sub c} is also improved by this new process. From the analysis of E-J characteristics, we have found out that the shape of statistical distribution of J{sub c} in the new process becomes sharper than that of the previous one. These results indicate that the uniformity of YBCO layer is improved by the new process. Furthermore, analytical expression of E-J characteristics, which is based on a percolation model and a scaling law of the pinning force density, shows good agreement with the experimental results. This allows us to predict the critical current property at arbitrary conditions of T and B even if we could not have measured data. For example, it is predicted that J{sub c} could be about 1 x 10{sup 10} A/m{sup 2} at 4.2 K and 30 T parallel to the c-axis.

  19. Introduction of the new process and quality control methods in fuel fabrication at Siemens/ANF

    International Nuclear Information System (INIS)

    Rogge, K.T.; Fickers, H.H.; Doerr, W.

    2000-01-01

    The central point of ANFs quality philosophy is the process of continuous improvements. With respect to the causes of defects and the efforts needed for elimination, the importance of continuous improvements is evident. In most of the cases, defects are caused in the initial stages of a product but the majority of the problems will be only detected during fabrication and inspection and in the worst case when the product is already in use. Goal of the improvement process is to assure a high product quality. Therefore, the efforts are focused on robust and centered processes. A reasonable quality planning is the basis for achieving and maintaining the quality targets. Quality planning includes prefabrication studies, in-process inspections and final inspections. The inspections provide a large amount of various quality data, process parameters as well as product proper-ties. Key data will be defined and subjected to a statistical analysis. In view of the effectiveness of the analysis, it is important, that the process parameters which influence the characteristics of the product are well known and that appropriate methods for data evaluation and visualization will be used. Main approach of the data visualization is to obtain a tighter control of the product properties and to improve the process robustness by implementation of defined improvements. With respect to the fuel safety and fuel performance, the presentation shows for typical product quality characteristics some examples of visualized quality data. The examples includes the integrity of the pellet column (rod scanner results), the spring force of PWR spacers (critical characteristic with regard to rod fretting) and the spacer intersection weld size (thermo-hydraulic fuel bundle behaviour). The presentation also includes an example for the statistical process control, the in-line surveillance of the fuel rod weld parameters which assures the integrity of the welds within tight tolerance ranges. The quality

  20. All polymer, injection molded nanoslits, fabricated through two-level UV-LIGA processes

    DEFF Research Database (Denmark)

    Østergaard, Peter Friis; Matteucci, Marco; Marie, Rodolphe

    2012-01-01

    Micro- and nanofluidic systems fabricated in silicon and glass substrates are expensive and have long production cycles. To minimize the time used by researchers to fabricate their systems, rather than using them, medium to high volume throughput of specific chips, containing fluidic channels...... in the polymer with the use of chips in different colors....

  1. Improvement of the obtention process of {sup 131} I of ININ through studies of equipment design and process parameters fitting in the simulator; Perfeccionamiento del proceso de obtencion del {sup 131} I del ININ mediante estudios de diseno del equipo y ajustes de parametros del proceso en el simulador

    Energy Technology Data Exchange (ETDEWEB)

    Zepeda M, M.C

    2006-07-01

    The main objective of the work was to achieve a high yield of the reaction that happens among the vapors of {sup 131} I and the NaOH to obtain sodium iodide (Na{sup 131} I) in solution optimizing the contact time of the molecules in gaseous state of {sup 131} I with the NaOH molecules through the bubbling velocity of the {sup 131} I in the solution of NaOH 0.1 N, as well as the operation temperature during the distillation process by dry via starting from tellurium dioxide (TeO{sub 2}) with the purpose of that the {sup 131} I that is obtained in the form of Na{sup 131} I solution presents the necessary quality that allows to distribute it in the market. The particular objectives were: a) To improve the distillation equipment used for the obtaining of {sup 131} I starting from irradiated tellurium dioxide redrawing the dilution system with the purpose of recovering the {sup 131} I in a minimum volume of sodium hydroxide (NaOH). b) To achieve a bigger time of contact among the molecules of {sup 131} I in gaseous state with the molecules of NaOH in solution through the bubbling velocity and of the redrawing of the dilution system. c) To implement the production of {sup 131} I by dry distillation via starting from tellurium dioxide, obtaining it with a high radionuclide and radiochemical purity. d) To obtain {sup 131} I with the necessary specifications that it marks the pharmacopoeia and it can be used with medical ends. (Author)

  2. Design of earth network in electric substations; Diseno de redes de tierra en subestaciones electricas

    Energy Technology Data Exchange (ETDEWEB)

    Raull-Martin, J. [Universidad Nacional Autonoma de Mexico, Mexico, D.F. (Mexico)

    2000-09-01

    The purpose of this paper is to present a summarized version of the different types of construction of grounding systems, as web as their materials and formulas, which are necessary and useful for the design and building of a grounding network for medium to high voltage facilities. A description is also made of how to determine the electrical resistivity of subsoil layers with different physical characteristics. Several illustrative examples are also solved in the paper. [Spanish] El proposito de este articulo es presentar de manera resumida los diferentes tipos de construccion de los sistemas de tierra, asi como sus materiales y formulas, los cuales son necesarios y utiles para el diseno y edificacion de una red de tierra para instalaciones de mediana y alta tension. Se describe tambien la obtencion de las diferentes resistividades que presentan los terrenos con diversas caracteristicas fisicas. Asi mismo, se solucionan ejercicios ilustrativos a lo largo del articulo.

  3. Substations grounding systems design; Diseno de sistemas de conexion a tierra en subestaciones

    Energy Technology Data Exchange (ETDEWEB)

    Velazquez Sanchez, Raul [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1986-12-31

    The grounding systems have been the object of a great number of analytical and experimental studies in the past 15 years, that have given rise to research reports on the several aspects involved in this technique. In this work are briefly reviewed various aspects that is necessary to take into account for its design, analysis and put in operation. [Espanol] Los sistemas de conexion a tierra han sido objeto de gran cantidad de estudios analiticos y experimentales en los pasados quince anos, que han dado origen a informes de investigacion sobre los diversos aspectos que involucra esta tecnica. En este trabajo se revisan brevemente diversos aspectos que es necesario considerar para su diseno, analisis y puesta en operacion.

  4. Voltage controller design for air conditioning; Diseno de controlador de voltaje para aire acondicionado

    Energy Technology Data Exchange (ETDEWEB)

    Garcia Andrade, R; Lopez Villalobos, J.J; Valderrama Chairez, J; Ramirez, R.L. [Instituto Tecnologico de Nuevo Leon, Guadalupe, Nuevo Leon (Mexico)]. E-mails: roxana_garciaandrade@yahoo.com; xe2n@yahoo.com.mx; jose.valderrama@ieee.org

    2013-03-15

    This paper discusses the design of a voltage controller for an air conditioning system in order to generate additional power in activation or startup of the system, for which as a first stage is presented the modeling power generation of electric current through alternative means, such as solar energy. The results of this study will be the basis for development of the physical prototype of this system controller. [Spanish] El presente trabajo trata sobre el diseno de un controlador de voltaje para un sistema de aire acondicionado con el fin de generar energia adicional en la activacion o arranque de dicho sistema, para lo cual como primer fase se presenta el modelado de la generacion de corriente electrica mediante medios alternos, como lo es la energia solar. Los resultados de este trabajo seran la base para desarrollo del prototipo fisico de este sistema controlador.

  5. Development of Impregnated Agglomerate Pelletization (IAP) process for fabrication of (Th,U)O 2 mixed oxide pellets

    Science.gov (United States)

    Khot, P. M.; Nehete, Y. G.; Fulzele, A. K.; Baghra, Chetan; Mishra, A. K.; Afzal, Mohd.; Panakkal, J. P.; Kamath, H. S.

    2012-01-01

    Impregnated Agglomerate Pelletization (IAP) technique has been developed at Advanced Fuel Fabrication Facility (AFFF), BARC, Tarapur, for manufacturing (Th, 233U)O 2 mixed oxide fuel pellets, which are remotely fabricated in hot cell or shielded glove box facilities to reduce man-rem problem associated with 232U daughter radionuclides. This technique is being investigated to fabricate the fuel for Indian Advanced Heavy Water Reactor (AHWR). In the IAP process, ThO 2 is converted to free flowing spheroids by powder extrusion route in an unshielded facility which are then coated with uranyl nitrate solution in a shielded facility. The dried coated agglomerate is finally compacted and then sintered in oxidizing/reducing atmosphere to obtain high density (Th,U)O 2 pellets. In this study, fabrication of (Th,U)O 2 mixed oxide pellets containing 3-5 wt.% UO 2 was carried out by IAP process. The pellets obtained were characterized using optical microscopy, XRD and alpha autoradiography. The results obtained were compared with the results for the pellets fabricated by other routes such as Coated Agglomerate Pelletization (CAP) and Powder Oxide Pelletization (POP) route.

  6. Planar silicon fabrication process for high-aspect-ratio micromachined parts

    Energy Technology Data Exchange (ETDEWEB)

    Barron, C.C.; Fleming, J.G. [Sandia National Labs., Albuquerque, NM (United States). Microelectronics Development Lab.

    1997-09-01

    Surface-micromachined silicon inertial sensors are limited to relatively high-G applications in part because of the fundamental limitations on proof mass imposed by the manufacturing technology. At the same time, traditional micromolding technologies such as LIGA do not lend themselves to integration with electronics, a capability which is equally necessary for high-performance inertial sensors. The silicon micromolding processes described in this report promise to offer both larger proof masses and integrability with on-chip electronics. In Sandia`s silicon micromolding process, the proof mass is formed using a mold which is first recessed into the substrate using a deep silicon trench etch, then lined with a sacrificial or etch-stop layer, and filled with mechanical polysilicon. Since the mold is recessed into the substrate, the whole micromechanical structure can be formed, planarized, and integrated with standard silicon microelectronic circuits before the release etch. In addition, unlike surface-micromachined parts, the thickness of the molded parts is limited by the depth of the trench etch (typically 10--50 {micro}m) rather than the thickness of deposited polysilicon (typically 2 {micro}m). The fact that the high-aspect-ratio section of the device is embedded in the substrate enables the monolithic integration of high-aspect-ratio parts with surface-micromachined mechanical parts, and, in the future, also electronics. The authors anticipate that such an integrated mold/surface micromachining/electronics process will offer versatile high-aspect-ratio micromachined structures that can be batch-fabricated and monolithically integrated into complex microelectromechanical systems including high-performance inertial sensing systems.

  7. Development and demonstration of manufacturing processes for fabricating graphite/Larc-160 polyimide structural elements, part 4, paragraph C

    Science.gov (United States)

    1981-01-01

    Progress in the development of processes for production of Celion/LARC-160 graphite-polyimide materials, quality control methods, and the fabrication of Space Shuttle composite structure components is reported. The formulation and processing limits for three batches of resin are presented. Process improvements for simplification of the imidizing and autoclave cure cycles are described. Imidized and autoclave cured test panels were prepared. Celion/LARC-160 cure process verification and the fabrication of honeycomb sandwich panel elements and skin/stringer panels are described. C-scans of laminates imidized at 163 C to 218 C for periods from 30 to 180 minutes, and of process verification laminates made from different batches of prepreg are presented. Failure modes and load/strain characteristics of sandwich elements and C-scans of stringer to skin bond joints are also given.

  8. Evaluation of mechanical properties for spherical magnetic regenerator materials fabricated by rapid solidification process

    International Nuclear Information System (INIS)

    Okamura, M.; Sori, N.; Saito, A.

    1997-01-01

    Various magnetic regenerator materials, such as Er 3 Ni, Er 3 Co and ErNi, are fabricated in the form of a spherical particle by a rapid solidification process. 4 K level refrigeration has been obtained by a GM refrigerator using these materials. However, the magnetic regenerator materials are considered brittle, as they are intermetallic compounds. It is important to evaluate the mechanical properties of these materials to confirm reliability as a regenerator material. In this paper, experimental results of compression and vibration tests for magnetic regenerator materials are described. The technical point of this study is to use spherical particles as test samples. The compressive stress of 20 MPa was applied to these spherical particles and no fractured spheres were observed. Similarly, no fractured spheres were found after the vibration test, in which the maximum acceleration was 30 X 9.8 m/s 2 and the number of vibration times was 1 X 10 6 , insofar as there was no room to stir spherical particles in a regenerator. In practice, the reliability of magnetic regenerator materials has been confirmed by a long-run test of 7,000 h in a usual GM refrigerator

  9. Fabrication of micro-hollow fiber by electrospinning process in near-critical carbon dioxide

    International Nuclear Information System (INIS)

    Okamoto, Koichi; Wahyudiono,; Kanda, Hideki; Goto, Motonobu; Machmudah, Siti; Okubayashi, Satoko; Fukuzato, Ryuichi

    2014-01-01

    Electrospinning is a simple technique that has gained much attention because of its capability and feasibility in the fabrication of large quantities of fibers from polymer with diameters ranging in nano-microscale. These fibers provided high surface area to volume ratios, and it was of considerable interest for many applications, such as nanoparticle carriers in controlled release, scaffolds in tissue engineering, wound dressings, military wear with chemical and biological toxin-resistance, nanofibrous membranes or filters, and electronic sensors. Recently there has been a great deal of progress in the potential applications of hollow fibers in microfluids, photonics, and energy storage. In this work, electrospinning was conducted under high-pressure carbon dioxide (CO 2 ) to reduce the viscosity of polymer solution. The experiments were conducted at 313 K and ∼8.0 MPa. Polymer solution containing 5 wt% polymers which prepared in dichloromethane (DCM) with polyvinylpyrrolidone (PVP) to poly-L-lactic acid (PLLA) ratio 80:20 was used as a feed solution. The applied voltage was 15 kV and the distance of nozzle and collector was 8 cm. The morphology and structure of the fibers produced were observed using scanning electron microscopy (SEM). Under pressurized CO 2 , PVP electrospun was produced without bead formation with diameter ranges of 608.50 - 7943.19 nm. These behaviors hold the potential to considerably improve devolatilization electrospinning processes

  10. Highly Magneto-Responsive Elastomeric Films Created by a Two-Step Fabrication Process

    KAUST Repository

    Marchi, Sophie

    2015-08-24

    An innovative method for the preparation of elastomeric magnetic films with increased magneto-responsivity is presented. Polymeric films containing aligned magnetic microchains throughout their thickness are formed upon the magnetophoretic transport and assembly of microparticles during polymer curing. The obtained films are subsequently magnetized at a high magnetic field of 3 T directed parallel to the orientation of the microchains. We prove that the combination of both alignment of the particles along a favorable direction during curing and the subsequent magnetization of the solid films induces an impressive increase of the films’ deflection. Specifically, the displacements reach few millimeters, up to 85 times higher than those of the nontreated films with the same particle concentration. Such a process can improve the performance of the magnetic films without increasing the amount of magnetic fillers and, thus, without compromising the mechanical properties of the resulting composites. The proposed method can be used for the fabrication of magnetic films suitable as components in systems in which large displacements at relatively low magnetic fields are required, such as sensors and drug delivery or microfluidic systems, especially where remote control of valves is requested to achieve appropriate flow and mixing of liquids.

  11. Fabrication process and electromagnetic wave absorption characterization of a CNT/Ni/epoxy nanocomposite.

    Science.gov (United States)

    Ryu, Seongwoo; Mo, Chan Bin; Lee, Haeshin; Hong, Soon Hyung

    2013-11-01

    Since carbon nanotube (CNT) was first discovered in 1991, it has been considered as a viable type of conductive filler for electromagnetic wave absorption materials in the GHz range. In this paper, pearl-necklace-structure CNT/Ni nano-powders were fabricated by a polyol process as conductive fillers. Compared to synthesized CNT, pearl-necklace Ni-decorated CNT increased the electrical conductivity by an order of 1 due to the enhancement of the Ni-conductive network. Moreover, the decorated Ni particles prevented the agglomeration of CNTs by counterbalancing the Van der Walls interaction between the CNTs. A CNT/Ni nanocomposite showed a homogeneous dispersion in an epoxy-based matrix. This enhanced physical morphology and electrical properties lead to an increase in the loss tangent and reflection loss in the CNT/Ni/Epoxy nanocomposite compared to these characteristics of a CNT/Epoxy nanocomposite in range of 8-12 GHz. The electromagnetic wave absorption properties of CNT/Ni/epoxy nanocomposites will provide enormous opportunities for electronic applications where lightweight EMI shielding or electro-magnetic wave absorption properties are necessary.

  12. Fast-dissolving core-shell composite microparticles of quercetin fabricated using a coaxial electrospray process.

    Directory of Open Access Journals (Sweden)

    Chen Li

    Full Text Available This study reports on novel fast-dissolving core-shell composite microparticles of quercetin fabricated using coaxial electrospraying. A PVC-coated concentric spinneret was developed to conduct the electrospray process. A series of analyses were undertaken to characterize the resultant particles in terms of their morphology, the physical form of their components, and their functional performance. Scanning and transmission electron microscopies revealed that the microparticles had spherical morphologies with clear core-shell structure visible. Differential scanning calorimetry and X-ray diffraction verified that the quercetin active ingredient in the core and sucralose and sodium dodecyl sulfate (SDS excipients in the shell existed in the amorphous state. This is believed to be a result of second-order interactions between the components; these could be observed by Fourier transform infrared spectroscopy. In vitro dissolution and permeation studies showed that the microparticles rapidly released the incorporated quercetin within one minute, and had permeation rates across the sublingual mucosa around 10 times faster than raw quercetin.

  13. A novel fabrication method of carbon electrodes using 3D printing and chemical modification process.

    Science.gov (United States)

    Tian, Pan; Chen, Chaoyang; Hu, Jie; Qi, Jin; Wang, Qianghua; Chen, Jimmy Ching-Ming; Cavanaugh, John; Peng, Yinghong; Cheng, Mark Ming-Cheng

    2017-11-23

    Three-dimensional (3D) printing is an emerging technique in the field of biomedical engineering and electronics. This paper presents a novel biofabrication method of implantable carbon electrodes with several advantages including fast prototyping, patient-specific and miniaturization without expensive cleanroom. The method combines stereolithography in additive manufacturing and chemical modification processes to fabricate electrically conductive carbon electrodes. The stereolithography allows the structures to be 3D printed with very fine resolution and desired shapes. The resin is then chemically modified to carbon using pyrolysis to enhance electrochemical performance. The electrochemical characteristics of 3D printing carbon electrodes are assessed by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The specific capacitance of 3D printing carbon electrodes is much higher than the same sized platinum (Pt) electrode. In-vivo electromyography (EMG) recording, 3D printing carbon electrodes exhibit much higher signal-to-noise ratio (40.63 ± 7.73) than Pt electrodes (14.26 ± 6.83). The proposed biofabrication method is envisioned to enable 3D printing in many emerging applications in biomedical engineering and electronics.

  14. Experimental and Numerical Simulation Research on Micro-Gears Fabrication by Laser Shock Punching Process

    Directory of Open Access Journals (Sweden)

    Huixia Liu

    2015-07-01

    Full Text Available The aim of this paper is to fabricate micro-gears via laser shock punching with Spitlight 2000 Nd-YAG Laser, and to discuss effects of process parameters namely laser energy, soft punch properties and blank-holder on the quality of micro-gears deeply. Results show that dimensional accuracy is the best shocked at 1690 mJ. Tensile fracture instead of shear fracture is the main fracture mode under low laser energy. The soft punch might cause damage to punching quality when too high energy is employed. Appropriate thickness and hardness of soft punch is necessary. Silica gel with 200 µm in thickness is beneficial to not only homogenize energy but also propagate the shock wave. Polyurethane films need more energy than silica gel with the same thickness. In addition, blank-holders with different weight levels are used. A heavier blank-holder is more beneficial to improve the cutting quality. Furthermore, the simulation is conducted to reveal typical stages and the different deformation behavior under high and low pulse energy. The simulation results show that the fracture mode changes under lower energy.

  15. Permeability Tests of Fiber Fabrics in the Vacuum Assisted Resin Transfer Molding Process

    Science.gov (United States)

    Changchun, Wang; Guanghui, Bai; Yang, Wang; Boming, Zhang; Lijian, Pan

    2015-08-01

    A special device is designed to measure the in-plane and through-thickness permeability of a preform for the vacuum assisted resin transfer molding (VARTM) process. The device is composed of pressure control module, aluminum experimental platform, thickness test module, and pressure test module, which is controlled by a computer. Two kinds of experiments were conducted for carbon fiber noncrimp biaxial fabrics to verify the reliability of the new device based on constant pressure injection. The two experiments are composed of: (1) testing of in-plane permeability for 1, 5, 10 and 20 layers with the method of the line injection by comparing the two conventional methods; (2) testing of the through-thickness permeability for the laminate denoted as [±45] 20 with the central injection method. The results show: (1) the in-plane permeability decrease with the increase of layer number and the permeability for 20 layers is only 62 % of the one layer; (2) the in-plane permeability is an order of magnitude greater than through-thickness permeability based on experimental results of laminate denoted as [±45] 20. A good agreement obtained between the device and two comparison methods proves the validity of the device.

  16. Fabrication of nano-sized magnetic tunnel junctions using lift-off process assisted by atomic force probe tip.

    Science.gov (United States)

    Jung, Ku Youl; Min, Byoung-Chul; Ahn, Chiyui; Choi, Gyung-Min; Shin, Il-Jae; Park, Seung-Young; Rhie, Kungwon; Shin, Kyung-Ho

    2013-09-01

    We present a fabrication method for nano-scale magnetic tunnel junctions (MTJs), employing e-beam lithography and lift-off process assisted by the probe tip of atomic force microscope (AFM). It is challenging to fabricate nano-sized MTJs on small substrates because it is difficult to use chemical mechanical planarization (CMP) process. The AFM-assisted lift-off process enables us to fabricate nano-sized MTJs on small substrates (12.5 mm x 12.5 mm) without CMP process. The e-beam patterning has been done using bi-layer resist, the poly methyl methacrylate (PMMA)/ hydrogen silsesquioxane (HSQ). The PMMA/HSQ resist patterns are used for both the etch mask for ion milling and the self-aligned mask for top contact formation after passivation. The self-aligned mask buried inside a passivation oxide layer, is readily lifted-off by the force exerted by the probe tip. The nano-MTJs (160 nm x 90 nm) fabricated by this method show clear current-induced magnetization switching with a reasonable TMR and critical switching current density.

  17. Fabrication of Copper-Rich Cu-Al Alloy Using the Wire-Arc Additive Manufacturing Process

    Science.gov (United States)

    Dong, Bosheng; Pan, Zengxi; Shen, Chen; Ma, Yan; Li, Huijun

    2017-12-01

    An innovative wire-arc additive manufacturing (WAAM) process is used to fabricate Cu-9 at. pct Al on pure copper plates in situ, through separate feeding of pure Cu and Al wires into a molten pool, which is generated by the gas tungsten arc welding (GTAW) process. After overcoming several processing problems, such as opening the deposition molten pool on the extremely high-thermal conductive copper plate and conducting the Al wire into the molten pool with low feed speed, the copper-rich Cu-Al alloy was successfully produced with constant predesigned Al content above the dilution-affected area. Also, in order to homogenize the as-fabricated material and improve the mechanical properties, two further homogenization heat treatments at 1073 K (800 °C) and 1173 K (900 °C) were applied. The material and mechanical properties of as-fabricated and heat-treated samples were compared and analyzed in detail. With increased annealing temperatures, the content of precipitate phases decreased and the samples showed gradual improvements in both strength and ductility with little variation in microstructures. The present research opened a gate for in-situ fabrication of Cu-Al alloy with target chemical composition and full density using the additive manufacturing process.

  18. Energy savings in buildings through the architectonic design; Ahorro de energa en edificaciones a traves de diseno arquitectonico

    Energy Technology Data Exchange (ETDEWEB)

    Figueroa Castrejon, A. [Universidad Autnoma Metropolitana-Azcapotzalco, Division de Ciencias y Artes para el Diseno, Laboratorio de Arquitectura Bioclimatica (Mexico)

    1997-12-31

    This paper points out the problems the existing buildings have in its architectonic design and alternatives presented to improve their habitability and energy consumption, making reference to national cases and to the social-economic environment of our country. [Espanol] El presente trabajo senala los problemas que tienen las edificaciones actuales en su diseno arquitectonico y las alternativas que se presentan para mejorar su habitabilidad y consumo energetico, haciendo referencia a los casos nacionales y al entorno socioeconmico de nuestro pas.

  19. Fabricating process of hollow out-of-plane Ni microneedle arrays and properties of the integrated microfluidic device

    Science.gov (United States)

    Zhu, Jun; Cao, Ying; Wang, Hong; Li, Yigui; Chen, Xiang; Chen, Di

    2013-07-01

    Although microfluidic devices that integrate microfluidic chips with hollow out-of-plane microneedle arrays have many advantages in transdermal drug delivery applications, difficulties exist in their fabrication due to the special three-dimensional structures of hollow out-of-plane microneedles. A new, cost-effective process for the fabrication of a hollow out-of-plane Ni microneedle array is presented. The integration of PDMS microchips with the Ni hollow microneedle array and the properties of microfluidic devices are also presented. The integrated microfluidic devices provide a new approach for transdermal drug delivery.

  20. Novel silicon fabrication process for high-aspect-ratio micromachined parts

    Energy Technology Data Exchange (ETDEWEB)

    Fleming, J.G.; Barron, C.C.

    1995-08-01

    Bulk micromachining generally refers to processes involving wet chemical etching of structures formed out of the silicon substrate and so is limited to fairly large, crude structures. Surface micromachining allows intricate patterning of thin films of polysilicon and other materials to form essentially two-dimensional layered parts (since the thickness of the parts is limited by the thickness of the deposited films). There is a third type of micromachining in which the part is formed by filling a mold which was defined by photolithographic means. Historically micromachining molds have been formed in some sort of photopolymer, be it with x-ray lithography (``LIGA``) or more conventional UV lithography, with the aim of producing piece parts. Recently, however, several groups including ours at Sandia have independently come up with the idea of forming the mold for mechanical parts by etching into the silicon substrate itself. In Sandia`s mold process, the mold is recessed into the substrate using a deep silicon trench etch, lined with a sacrificial or etch-stop layer, and then filled with any of a number of mechanical materials. The completed structures are not ejected from the mold to be used as piece parts rather, the mold is dissolved from around selected movable segments of the parts, leaving the parts anchored to the substrate. Since the mold is recessed into the substrate, the whole micromechanical structure can be formed, planarized, and integrated with standard silicon microelectronic circuits before the release etch. In addition, unlike surface-micromachined parts, the thickness of the molded parts is limited by the depth of the trench etch (typically 10--50 {mu}m) rather than the thickness of deposited polysilicon (typically 2 {mu}m). The capability of fabricating thicker (and therefore much stiffer and more massive) parts is critical for motion-sensing structures involving large gimballed platforms, proof masses, etc.

  1. Solution processed Al doped ZnO film fabrication through electrohydrodynamic atomization

    International Nuclear Information System (INIS)

    Muhammad, Nauman Malik; Duraisamy, Navaneethan; Dang, Hyun-Woo; Jo, Jeongdai; Choi, Kyung-Hyun

    2012-01-01

    In this study, highly transparent, 250 nm thick films of Aluminum doped Zinc-oxide (ZnO:Al) are achieved on glass substrates at ambient conditions through a solution processing technique called electrohydrodynamic atomization. A 10 wt.% monodispersed solution containing 6% ZnO:Al nanoparticles (ZnO/Al 2 O 3 ) in ethanol has been synthesized first and then used in the deposition process as the working solution. Pure and uniform transparent films with an average transmittance of 93% have been deposited with crystal structure exhibiting both zincite and gahnite phases. Surface composition purity has been confirmed using X-ray photoelectron spectroscopy technique and the clear indication of Zn-2p and Al-2p peaks confirms surface integrity. Fourier Transform Infrared analysis further confirms the presence of aluminum in the samples. The electrical properties are studied by recording and analyzing the current–voltage (I–V) measurements and the resistivity has been estimated from the slope of the IV-curve which is approximately 25 mΩ.cm. The layer roughness has been characterized using atomic force microscopy. - Highlights: ►Aluminum doped Zinc oxide (ZnO:Al) films are made via electrohydrodynamic atomization. ►ZnO:Al nano-particle ink is used to form thin films in single step at room conditions. ►Scanning electron and atomic force microscopes confirm fine layer characteristics. ►X-ray photoelectron and Fourier Transform-Infrared spectroscope confirm film purity. ►Transparent and conductive films have been fabricated with wurtzite structure.

  2. Influence of Stored Strain on Fabricating of Al/SiC Nanocomposite by Friction Stir Processing

    Science.gov (United States)

    Khorrami, M. Sarkari; Kazeminezhad, M.; Kokabi, A. H.

    2015-05-01

    In this work, 1050 aluminum (Al) sheets were annealed and severely deformed by 1, 2, and 3 passes of constrained groove pressing process to obtain the various initial stored strain values of 0, 1.16, 2.32, and 3.48, respectively. Friction stir processing (FSP) was then applied using SiC nanoparticles to fabricate Al/SiC nanocomposite with approximately 1.5 vol pct reinforced particles. Microstructural examinations revealed that an increase in the initial stored strain of the base metal led to the formation of finer grain structure after 1 pass of FSP. The finer grain structure occurred in the stir zone where a sufficient amount of nanoparticles with a relatively proper distribution existed. However, the initial stored strain value had a contrary influence in the regions with low volume fraction of nanoparticles. In fact, more stored strain in the base metal provided more driving force for both nucleation and grain growth of newly recrystallized grains at the stir zone. Pinning effect of well-distributed nanoparticles could effectively retard grain growth leading to the formation of very fine grain structure. Also it was observed that the initial stored strain values did not have impressive rule in the microstructural evolutions at the stir zone during the second and third FSP passes signifying that all of the stored energy in the base metal would be released after 1 pass of FSP. The results obtained with microhardness measurement at the stir zone were fairly in agreement with those achieved by the microstructure assessments.

  3. Enhanced Fabrication Processes Development for High Actuator Count Deformable Mirrors, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose to design and fabricate a MEMS micromirror array consisting of 1021 ultra-flat, close-packed hexagonal mirror elements, each capable of 6mrad of tip and...

  4. Fabrication Process for Machined and Shrink-Fitted Impactor-Type Liners for the LOS Alamos Hedp Program

    Science.gov (United States)

    Randolph, B.

    2004-11-01

    Composite liners have been fabricated for the Los Alamos liner-driven High Energy Density Physics (HEDP) experiments using impactors formed by physical vapor deposition, and by machining and shrink fitting. Chemical vapor deposition has been proposed for some ATLAS liner applications. This paper describes the processes used to fabricate machined and shrink-fitted impactors; these processes have been used for copper impactors in 1100 aluminum liners and for 6061 T-6 aluminum impactors in 1100 aluminum liners. The most successful processes have been largely empirically developed and rely upon a combination of shrink-fitting and light press fitting. The processes used to date will be described along with some considerations for future composite liners for the HEDP Program.

  5. High-throughput fabrication of micrometer-sized compound parabolic mirror arrays by using parallel laser direct-write processing

    International Nuclear Information System (INIS)

    Yan, Wensheng; Gu, Min; Cumming, Benjamin P

    2015-01-01

    Micrometer-sized parabolic mirror arrays have significant applications in both light emitting diodes and solar cells. However, low fabrication throughput has been identified as major obstacle for the mirror arrays towards large-scale applications due to the serial nature of the conventional method. Here, the mirror arrays are fabricated by using a parallel laser direct-write processing, which addresses this barrier. In addition, it is demonstrated that the parallel writing is able to fabricate complex arrays besides simple arrays and thus offers wider applications. Optical measurements show that each single mirror confines the full-width at half-maximum value to as small as 17.8 μm at the height of 150 μm whilst providing a transmittance of up to 68.3% at a wavelength of 633 nm in good agreement with the calculation values. (paper)

  6. Process Optimization of Eco-Friendly Flame Retardant Finish for Cotton Fabric: a Response Surface Methodology Approach

    Science.gov (United States)

    Yasin, Sohail; Curti, Massimo; Behary, Nemeshwaree; Perwuelz, Anne; Giraud, Stephane; Rovero, Giorgio; Guan, Jinping; Chen, Guoqiang

    The n-methylol dimethyl phosphono propionamide (MDPA) flame retardant compounds are predominantly used for cotton fabric treatments with trimethylol melamine (TMM) to obtain better crosslinking and enhanced flame retardant properties. Nevertheless, such treatments are associated with a toxic issue of cancer-causing formaldehyde release. An eco-friendly finishing was used to get formaldehyde-free fixation of flame retardant to the cotton fabric. Citric acid as a crosslinking agent along with the sodium hypophosphite as a catalyst in the treatment was utilized. The process parameters of the treatment were enhanced for optimized flame retardant properties, in addition, low mechanical loss to the fabric by response surface methodology using Box-Behnken statistical design experiment methodology was achieved. The effects of concentrations on the fabric’s properties (flame retardancy and mechanical properties) were evaluated. The regression equations for the prediction of concentrations and mechanical properties of the fabric were also obtained for the eco-friendly treatment. The R-squared values of all the responses were above 0.95 for the reagents used, indicating the degree of relationship between the predicted values by the Box-Behnken design and the actual experimental results. It was also found that the concentration parameters (crosslinking reagents and catalysts) in the treatment formulation have a prime role in the overall performance of flame retardant cotton fabrics.

  7. Fabrication of nanostructured metal oxide films with supercritical carbon dioxide: Processing and applications

    Science.gov (United States)

    You, Eunyoung

    Nanostructured metal oxide films have many applications in catalysis, microelectronics, microfluidics, photovoltaics and other fields. Since the performance of a device depends greatly on the structure of the material, the development of methodologies that enable prescriptive control of morphology are of great interest. The focus of this work is to control the structure and properties of the nanostructured metal oxide films using novel synthetic schemes in supercritical fluids and to use those films as key building components in alternative energy applications. A supercritical fluid is a substance at a temperature and pressure above its critical point. It typically exhibits gas-like transport properties and liquid-like densities. Supercritical fluid deposition (SFD) utilizes these properties of supercritical CO2 (scCO2) to deposit chemically pure metal, oxides and alloys of metal films. SFD is a chemical vapor deposition (CVD)-like process in the sense that it uses similar metal organic precursors and deposits films at elevated temperatures. Instead of vaporizing or subliming the precursors, they are dissolved in supercritical fluids. SFD has typically shown to exhibit higher precursor concentrations, lower deposition temperatures, conformal deposition of films on high aspect ratio features as compared to CVD. In2 O3, ZnO and SnO2 are attractive materials because they are used in transparent conductors. SFD of these materials were studied and In2 O3 deposition kinetics using tris(2,2,6,6-tetramethyl-3,5-heptanedionato) In (III) as precursor were determined. Growth rate dependence on the deposition temperature and the precursor concentrations were studied and the physicochemical and optical properties of In2 O3 films were characterized. Metal oxide nanochannels that can potentially be used for microfluidics have been fabricated by sequentially performing nanoimprint lithography (NIL) and SFD. NIL was used to pattern photoresist grating on substrates and SFD of TiO2

  8. Deep x-ray lithography processing for batch fabrication of thick polymer-based antenna structures

    Science.gov (United States)

    Rashidian, Atabak; Klymyshyn, David M.; Boerner, Martin; Mohr, Jürgen

    2010-02-01

    Deep x-ray lithography is applied for the first time to fabricate polymer-based antenna structures with different portions of ceramic contents. To produce successful and viable antenna structures, three different methods are proposed using positive and negative tone resists. In the first method the structures are lithographically fabricated avoiding an intermediate molding step using SU-8 as a photosensitive resist filled with fine ceramic powder with particles in the submicron range. In the second and third methods a polymethylmethacrylate (PMMA) mold is first fabricated by x-ray lithography, and then SU-8/MMA mixed with the high ceramic powder content is injected into the mold. In these methods a final step of crosslinking for SU-8 and polymerization for MMA is also required. Optimized fabrication parameters allow the production of high quality antenna structures as thick as 2.3 mm. X-ray lithography capabilities in fabrication of antennas and other passive microwave components with special features reinforce the idea of fabricating integrated passive microwave circuits along with active circuits using this emerging technology.

  9. Polymer Microfluidics: Simple, Low-Cost Fabrication Process Bridging Academic Lab Research to Commercialized Production

    Directory of Open Access Journals (Sweden)

    Chia-Wen Tsao

    2016-12-01

    Full Text Available Using polymer materials to fabricate microfluidic devices provides simple, cost effective, and disposal advantages for both lab-on-a-chip (LOC devices and micro total analysis systems (μTAS. Polydimethylsiloxane (PDMS elastomer and thermoplastics are the two major polymer materials used in microfluidics. The fabrication of PDMS and thermoplastic microfluidic device can be categorized as front-end polymer microchannel fabrication and post-end microfluidic bonding procedures, respectively. PDMS and thermoplastic materials each have unique advantages and their use is indispensable in polymer microfluidics. Therefore, the proper selection of polymer microfabrication is necessary for the successful application of microfluidics. In this paper, we give a short overview of polymer microfabrication methods for microfluidics and discuss current challenges and future opportunities for research in polymer microfluidics fabrication. We summarize standard approaches, as well as state-of-art polymer microfluidic fabrication methods. Currently, the polymer microfluidic device is at the stage of technology transition from research labs to commercial production. Thus, critical consideration is also required with respect to the commercialization aspects of fabricating polymer microfluidics. This article provides easy-to-understand illustrations and targets to assist the research community in selecting proper polymer microfabrication strategies in microfluidics.

  10. Development and demonstration of manufacturing processes for fabricating graphite/Larc-160 polyimide structural elements, part 4, paragraph B

    Science.gov (United States)

    1981-01-01

    Progress in the development of processes for production of Celion/LARC-160 graphite-polyimide materials, quality control, and the fabrication of Space Shuttle composite structure components is reported. Liquid chromatographic analyses of three repeatibility batches were performed and are compared to previous Hexcel standard production and to variables study LARC-160 intermediate resins. Development of processes for chopped fiber molding are described and flexural strength, elastic modulus, and other physical and mechanical properties of the molding are presented.

  11. 3D printed electromagnetic transmission and electronic structures fabricated on a single platform using advanced process integration techniques

    Science.gov (United States)

    Deffenbaugh, Paul Issac

    3D printing has garnered immense attention from many fields including in-office rapid prototyping of mechanical parts, outer-space satellite replication, garage functional firearm manufacture, and NASA rocket engine component fabrication. 3D printing allows increased design flexibility in the fabrication of electronics, microwave circuits and wireless antennas and has reached a level of maturity which allows functional parts to be printed. Much more work is necessary in order to perfect the processes of 3D printed electronics especially in the area of automation. Chapter 1 shows several finished prototypes of 3D printed electronics as well as newly developed techniques in fabrication. Little is known about the RF and microwave properties and applications of the standard materials which have been developed for 3D printing. Measurement of a wide variety of materials over a broad spectrum of frequencies up to 10 GHz using a variety of well-established measurement methods is performed throughout chapter 2. Several types of high frequency RF transmission lines are fabricated and valuable model-matched data is gathered and provided in chapter 3 for future designers' use. Of particular note is a fully 3D printed stripline which was automatically fabricated in one process on one machine. Some core advantages of 3D printing RF/microwave components include rapid manufacturing of complex, dimensionally sensitive circuits (such as antennas and filters which are often iteratively tuned) and the ability to create new devices that cannot be made using standard fabrication techniques. Chapter 4 describes an exemplary fully 3D printed curved inverted-F antenna.

  12. Fabrication of micro- and nano-structured materials using mask-less processes

    International Nuclear Information System (INIS)

    Roy, Sudipta

    2007-01-01

    Micro- and nano-scale devices are used in electronics, micro-electro- mechanical, bio-analytical and medical components. An essential step for the fabrication of such small scale devices is photolithography. Photolithography requires a master mask to transfer micrometre or sub-micrometre scale patterns onto a substrate. The requirement of a physical, rigid mask can impede progress in applications which require rapid prototyping, flexible substrates, multiple alignment and 3D fabrication. Alternative technologies, which do not require the use of a physical mask, are suitable for these applications. In this paper mask-less methods of micro- and nano-scale fabrication have been discussed. The most common technique, which is the laser direct imaging (LDI), technique has been applied to fabricate micrometre scale structures on printed circuit boards, glass and epoxy. LDI can be combined with chemical methods to deposit metals, inorganic materials as well as some organic entities at the micrometre scale. Inkjet technology can be used to fabricate micrometre patterns of etch resists, organic transistors as well as arrays for bioanalysis. Electrohydrodynamic atomisation is used to fabricate micrometre scale ceramic features. Electrochemical methodologies offer a variety of technical solutions for micro- and nano-fabrication owing to the fact that electron charge transfer can be constrained to a solid-liquid interface. Electrochemical printing is an adaptation of inkjet printing which can be used for rapid prototyping of metallic circuits. Micro-machining using nano-second voltage pulses have been used to fabricate high precision features on metals and semiconductors. Optimisation of reactor, electrochemistry and fluid flow (EnFACE) has also been employed to transfer micrometre scale patterns on a copper substrate. Nano-scale features have been fabricated by using specialised tools such as scanning tunnelling microscopy, atomic force microscopy and focused ion beam. The

  13. DEVELOPMENT OF A FABRICATION PROCESS FOR SOL-GEL/METAL HYDRIDE COMPOSITE GRANULES

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, E; Eric Frickey, E; Leung Heung, L

    2004-02-23

    An external gelation process was developed to produce spherical granules that contain metal hydride particles in a sol-gel matrix. Dimensionally stable granules containing metal hydrides are needed for applications such as hydrogen separation and hydrogen purification that require columns containing metal hydrides. Gases must readily flow through the metal hydride beds in the columns. Metal hydrides reversibly absorb and desorb hydrogen and hydrogen isotopes. This is accompanied by significant volume changes that cause the metal hydride to break apart or decrepitate. Repeated cycling results in very fine metal hydride particles that are difficult to handle and contain. Fine particles tend to settle and pack making it more difficult to flow gases through a metal hydride bed. Furthermore, the metal hydrides can exert a significant force on the containment vessel as they expand. These problems associated with metal hydrides can be eliminated with the granulation process described in this report. Small agglomerates of metal hydride particles and abietic acid (a pore former) were produced and dispersed in a colloidal silica/water suspension to form the feed slurry. Fumed silica was added to increase the viscosity of the feed slurry which helped to keep the agglomerates in suspension. Drops of the feed slurry were injected into a 27-foot tall column of hot ({approx}70 C), medium viscosity ({approx}3000 centistokes) silicone oil. Water was slowly evaporated from the drops as they settled. The drops gelled and eventually solidified to form spherical granules. This process is referred to as external gelation. Testing was completed to optimize the design of the column, the feed system, the feed slurry composition, and the operating parameters of the column. The critical process parameters can be controlled resulting in a reproducible fabrication technique. The residual silicone oil on the surface of the granules was removed by washing in mineral spirits. The granules were

  14. Simulation and optimization of a micromachined gyroscope using high-aspect-ratio micromachining fabrication process

    Science.gov (United States)

    Ruan, Aiwu Y.; Tse, Man S.; Chong, Gang Y.

    2001-11-01

    Micromachined gyroscopes rely on tuned vibration mode frequencies to measure rotation rates and typically have complex modes of vibration for the mechanical microstructures. Although there are many reports on how to exactly tune the drive and sense modes of vibration to maximize sensitivity of micromachined gyroscope, there are only few reports on the detailed analysis of modes of vibration. Modes of vibration are strongly dependent on the design parameters of the mechanical structure of the gyroscope including the dimension of the proof mass, types and dimensions of the suspension, and residual mechanical stress of the high aspect-ratio polysilicon film used to form the microstructures of the micromachined gyroscope. In this paper, an electrostatic drive and capacitive sense in-plane decoupled gyroscope for measuring vertical angular velocity is proposed to study the effects of the geometrical variables on modes of vibration. Finite-element analysis (FEA) simulation was performed on simplifiedmodel of the in-plane decoupled micromachined gyroscope microstructure. For optimal result the drive-mode and sense-mode suspensions of the micromachined gyroscope should be fabricated from thick polysilicon microstructure to give large aspect ratio suspension systems for the in-plane decoupled micromachined gyroscope. Folded-beam suspension design is recommended for the drive-mode suspension in order to relieve the residual stress of the thick polysilicon film for high aspect-ratio micromachine dgyroscope. It is critical to control the process variations of the suspension beam dimension, especially the beam width variation in order to achieve the goal of accurately control resonant frequencies of micromachined gyrocope.

  15. A fully integrated electrochemical biosensor platform fabrication process for cytokines detection.

    Science.gov (United States)

    Baraket, Abdoullatif; Lee, Michael; Zine, Nadia; Sigaud, Monique; Bausells, Joan; Errachid, Abdelhamid

    2017-07-15

    Interleukin-1b (IL-1b) and interleukin-10 (IL-10) biomarkers are one of many antigens that are secreted in acute stages of inflammation after left ventricle assisted device (LVAD) implantation for patients suffering from heart failure (HF). In the present study, we have developed a fully integrated electrochemical biosensor platform for cytokine detection at minute concentrations. Using eight gold working microelectrodes (WEs) the design will increase the sensitivity of detection, decrease the time of measurements, and allow a simultaneous detection of varying cytokine biomarkers. The biosensor platform was fabricated onto silicon substrates using silicon technology. Monoclonal antibodies (mAb) of anti-human IL-1b and anti-human IL-10 were electroaddressed onto the gold WEs through functionalization with 4-carboxymethyl aryl diazonium (CMA). Cyclic voltammetry (CV) was applied during the WE functionalization process to characterize the gold WE surface properties. Finally, electrochemical impedance spectroscopy (EIS) characterized the modified gold WE. The biosensor platform was highly sensitive to the corresponding cytokines and no interference with other cytokines was observed. Both cytokines: IL-10 and IL-1b were detected within the range of 1pgmL -1 to 15pgmL -1 . The present electrochemical biosensor platform is very promising for multi-detection of biomolecules which can dramatically decrease the time of analysis. This can provide data to clinicians and doctors concerning cytokines secretion at minute concentrations and the prediction of the first signs of inflammation after LVAD implantation. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. A three-mask process for fabricating vacuum-sealed capacitive micromachined ultrasonic transducers using anodic bonding.

    Science.gov (United States)

    Yamaner, F Yalçın; Zhang, Xiao; Oralkan, Ömer

    2015-05-01

    This paper introduces a simplified fabrication method for vacuum-sealed capacitive micromachined ultrasonic transducer (CMUT) arrays using anodic bonding. Anodic bonding provides the established advantages of wafer-bondingbased CMUT fabrication processes, including process simplicity, control over plate thickness and properties, high fill factor, and ability to implement large vibrating cells. In addition to these, compared with fusion bonding, anodic bonding can be performed at lower processing temperatures, i.e., 350°C as opposed to 1100°C; surface roughness requirement for anodic bonding is more than 10 times more relaxed, i.e., 5-nm rootmean- square (RMS) roughness as opposed to 0.5 nm for fusion bonding; anodic bonding can be performed on smaller contact area and hence improves the fill factor for CMUTs. Although anodic bonding has been previously used for CMUT fabrication, a CMUT with a vacuum cavity could not have been achieved, mainly because gas is trapped inside the cavities during anodic bonding. In the approach we present in this paper, the vacuum cavity is achieved by opening a channel in the plate structure to evacuate the trapped gas and subsequently sealing this channel by conformal silicon nitride deposition in the vacuum environment. The plate structure of the fabricated CMUT consists of the single-crystal silicon device layer of a silicon-on-insulator wafer and a thin silicon nitride insulation layer. The presented fabrication approach employs only three photolithographic steps and combines the advantages of anodic bonding with the advantages of a patterned metal bottom electrode on an insulating substrate, specifically low parasitic series resistance and low parasitic shunt capacitance. In this paper, the developed fabrication scheme is described in detail, including process recipes. The fabricated transducers are characterized using electrical input impedance measurements in air and hydrophone measurements in immersion. A representative

  17. Comparative Study of Laboratory-Scale and Prototypic Production-Scale Fuel Fabrication Processes and Product Characteristics

    International Nuclear Information System (INIS)

    Marshall, Douglas W.

    2014-01-01

    An objective of the High Temperature Gas Reactor fuel development and qualification program for the United States Department of Energy has been to qualify fuel fabricated in prototypic production-scale equipment. The quality and characteristics of the tristructural isotropic (TRISO) coatings on fuel kernels are influenced by the equipment scale and processing parameters. The standard deviations of some TRISO layer characteristics were diminished while others have become more significant in the larger processing equipment. The impact on statistical variability of the processes and the products, as equipment was scaled, are discussed. The prototypic production-scale processes produce test fuels meeting all fuel quality specifications. (author)

  18. Characterization of a fabrication process for the integration of superconducting qubits and rapid-single-flux-quantum circuits

    International Nuclear Information System (INIS)

    Castellano, Maria Gabriella; Groenberg, Leif; Carelli, Pasquale; Chiarello, Fabio; Cosmelli, Carlo; Leoni, Roberto; Poletto, Stefano; Torrioli, Guido; Hassel, Juha; Helistoe, Panu

    2006-01-01

    In order to integrate superconducting qubits with rapid-single-flux-quantum (RSFQ) control circuitry, it is necessary to develop a fabrication process that simultaneously fulfils the requirements of both elements: low critical current density, very low operating temperature (tens of millikelvin) and reduced dissipation on the qubit side; high operation frequency, large stability margins, low dissipated power on the RSFQ side. For this purpose, VTT has developed a fabrication process based on Nb trilayer technology, which allows the on-chip integration of superconducting qubits and RSFQ circuits even at very low temperature. Here we present the characterization (at 4.2 K) of the process from the point of view of the Josephson devices and show that they are suitable to build integrated superconducting qubits

  19. Praxis educativa ecopacifista de enriquecimiento curricular: Conceptuacion, diseno y divulgacion

    Science.gov (United States)

    Osorio, Carlos Agustin Muniz

    A general consensus exists that the present worldwide state of the natural environment is in crisis. Tied to this crisis, the social dimension presents a discouraging picture in aspects like violence and poverty. The predominant neoliberal economic system---ecocidal and genocidal---just as the production system that sustains it, affects this crisis. Puerto Rico, in its political and economic relationship with the United States of America, is not exempt of this situation. Education arises as an alternative to transform this reality. Science education has the potential to address these socio-environmental problems in a creative way. From a scientific educational framework, we conceptualized, designed and disseminated diverse approaches and tools that integrate socio-ecological and environmental aspects, as well as issues related to violence, conflict and peace. The central research questions were: At present, what are some of the main characteristics of the social-ecological and environmental global and local (glocal) issues and what relation do they have with formal education?; What is the ethical responsibility of science education when, facing social-ecological and environmental situations and issues concerning peace?; What educational foundations justify the "Praxis Educativa Ecopacifista de Enriquecimiento Curricular" as an alternative to the situations and issues considered?; What didactic tools do we propose?; What curricular design and revision processes do we propose? What dissemination processes do we propose? The nature of our methodology is qualitative and is centered around curricular design. It includes a research-theoretical dimension, a practical-research dimension, and systematizing of learning elements. We emphasize the conceptualization of the theoretical-philosophical and methodological dimensions of the ecopacifist approach and its fundamental principles. We highlight the praxis, integrating creativity, intelligence and talent development

  20. Rapid method for design and fabrication of passive micromixers in microfluidic devices using a direct-printing process.

    Science.gov (United States)

    Liu, Ai-Lin; He, Feng-yun; Wang, Kang; Zhou, Ting; Lu, Yu; Xia, Xing-hua

    2005-09-01

    We developed a facile and rapid one-step technique for design and fabrication of passive micromixers in microfluidic devices using a direct-printing process. A laser printing mechanism was dexterously adopted to pattern the microchannels with different gray levels using vector graphic software. With the present method, periodically ordered specific bas-relief microstructures can be easily fabricated on transparencies by a simple printing process. The size and shape of the resultant microstructures are determined by the gray level of the graphic software and the resolution of the laser printer. Patterns of specific bas-relief microstructures on the floor of a channel act as obstacles in the flow path for advection mixing, which can be used as efficient mixing elements. The mixing effect of the resultant micromixer in microfluidic devices was evaluated using CCD fluorescence spectroscopy. We found that the mixing performance depends strongly on the gray level values. Under optimal conditions, fast passive mixing with our periodic ordered patterns in microfluidic devices has been achieved at the very early stages of the laminar flow. In addition, fabrication of micromixers using the present versatile technique requires less than an hour. The present method is promising for fabrication of micromixers in microfluidic devices at low cost and without complicated devices and environment, providing a simple solution to mixing problems in the micro-total-analysis-systems field.

  1. Design and fuel fabrication processes for the AC-3 mixed-carbide irradiation test

    International Nuclear Information System (INIS)

    Latimer, T.W.; Chidester, K.M.; Stratton, R.W.; Ledergerber, G.; Ingold, F.

    1992-01-01

    The AC-3 test was a cooperative U.S./Swiss irradiation test of 91 wire-wrapped helium-bonded U-20% Pu carbide fuel pins irradiated to 8.3 at % peak burnup in the Fast Flux Test Facility. The test consisted of 25 pins that contained spherepac fuel fabricated by the Paul Scherrer Institute (PSI) and 66 pins that contained pelletized fuel fabricated by the Los Alamos National Laboratory. Design of AC-3 by LANL and PSI was begun in 1981, the fuel pins were fabricated from 1983 to 1985, and the test was irradiated from 1986 to 1988. The principal objective of the AC-3 test was to compare the irradiation performance of mixed-carbide fuel pins that contained either pelletized or sphere-pac fuel at prototypic fluence and burnup levels for a fast breeder reactor

  2. Examining the Roles of Emulsion Droplet Size and Surfactant in the Interfacial Instability-Based Fabrication Process of Micellar Nanocrystals

    Science.gov (United States)

    Sun, Yuxiang; Mei, Ling; Han, Ning; Ding, Xinyi; Yu, Caihao; Yang, Wenjuan; Ruan, Gang

    2017-06-01

    The interfacial instability process is an emerging general method to fabricate nanocrystal-encapsulated micelles (also called micellar nanocrystals) for biological detection, imaging, and therapy. The present work utilized fluorescent semiconductor nanocrystals (quantum dots or QDs) as the model nanocrystals to investigate the interfacial instability-based fabrication process of nanocrystal-encapsulated micelles. Our experimental results suggest intricate and intertwined roles of the emulsion droplet size and the surfactant poly (vinyl alcohol) (PVA) used in the fabrication process of QD-encapsulated poly (styrene-b-ethylene glycol) (PS-PEG) micelles. When no PVA is used, no emulsion droplet and thus no micelle is successfully formed; Emulsion droplets with large sizes ( 25 μm) result in two types of QD-encapsulated micelles, one of which is colloidally stable QD-encapsulated PS-PEG micelles while the other of which is colloidally unstable QD-encapsulated PVA micelles; In contrast, emulsion droplets with small sizes ( 3 μm or smaller) result in only colloidally stable QD-encapsulated PS-PEG micelles. The results obtained in this work not only help to optimize the quality of nanocrystal-encapsulated micelles prepared by the interfacial instability method for biological applications but also offer helpful new knowledge on the interfacial instability process in particular and self-assembly in general.

  3. Pilot-scale demonstration of the modified direct denitration process to prepare uranium oxide for fuel fabrication evaluation

    International Nuclear Information System (INIS)

    Kitts, F.G.

    1994-04-01

    The Uranium-Atomic Vapor Laser Isotope Separation (U-AVLIS) Program has the objective of developing a cost-competitive enrichment process that will ultimately replace the gaseous diffusion process used in the United States. Current nuclear fuel fabricators are set up to process only the UF 6 product from gaseous diffusion enrichment. Enriched uranium-iron alloy from the U-AVLIS separator system must be chemically converted into an oxide form acceptable to these fabricators to make fuel pellets that meet American Society for Testing and Materials (ASTM) and utility company specifications. A critical step in this conversion is the modified direct denitration (MDD) that has been selected and presented in the AVLIS Conceptual Design for converting purified uranyl nitrate to UO 3 to be shipped to fabricators for making UO 2 pellets for power reactor fuel. This report describes the MDD process, the equipment used, and the experimental work done to demonstrate the conversion of AVLIS product to ceramic-grade UO 3 suitable for making reactor-grade fuel pellets

  4. Effect of fabrication processes on mechanical properties of glass fiber reinforced polymer composites for 49 meter (160 foot recreational yachts

    Directory of Open Access Journals (Sweden)

    Dave (Dae-Wook Kim

    2010-03-01

    Full Text Available Polymer composite materials offer high strength and stiffness to weight ratio, corrosion resistance, and total life cost reductions that appeal to the marine industry. The advantages of composite construction have led to their incorporation in U.S. yacht hull structures over 46 meters (150 feet in length. In order to construct even larger hull structures, higher quality composites with lower cost production techniques need to be developed. In this study, the effect of composite hull fabrication processes on mechanical properties of glass fiber reinforced plastic (GFRP composites is presented. Fabrication techniques investigated during this study are hand lay-up (HL, vacuum infusion (VI, and hybrid (HL + VI processes. Mechanical property testing includes: tensile, compressive, and ignition loss sample analysis. Results demonstrate that the vacuum pressure implemented during composite fabrication has an effect on mechanical properties. The VI processed GFRP yields improved mechanical properties in tension/compression strengths and tensile modulus. The hybrid GFRP composites, however, failed in a sequential manor, due to dissimilar failure modes in the HL and VI processed sides. Fractography analysis was conducted to validate the mechanical property testing results.

  5. Woven Apparel Fabrics

    OpenAIRE

    Redmore, Nicola

    2012-01-01

    This chapter considers the different woven manufacturing\\ud processes used in the production of apparel fabrics. It details the mainapparel fabric types and looks at the key performance requirements of those fabrics, in relation to both the weave structure and the fibre type. The chapter then goes on to briefly describe important considerations in the design process and the various end uses for woven fabric. Application examples detailed towards the end of the chapter include fabrics that are...

  6. Comparison between Zr-Rh amorphous alloys fabricated by different processes

    International Nuclear Information System (INIS)

    Missell, F.P.

    1984-01-01

    It has been considered Zr-Rh amorphous alloys fabricated by sputtering and melt-spinning. For these materials, it was compared the superconducting transition temperatures T c , the superior critical field H c2 , the states density at Fermi energy N*, the dependence of T c with the hydrostatic pressure and results of differential thermic analysis. (A.C.A.S.) [pt

  7. Developments of steel fabrication processes for castings and ingots for forgings

    International Nuclear Information System (INIS)

    Fernandez, S.

    1980-01-01

    This chapter deals with a series of technological developments in the manufacture of steels which have occurred during the last years, in particular reporting the results obtained in Reinosa with some of these methods in the fabrication of castings as well as forgings and rolled products. (author)

  8. Processing and Electromagnetic Shielding Properties of Multifunctional Metal Composite Knitted Fabric used as Socks

    Directory of Open Access Journals (Sweden)

    Yu Zhicai

    2016-01-01

    Full Text Available In this research, a type of bamboo charcoal polyester (BC-PET/antibacterial nylon(AN/stainless steel wire (SSW metal composite yarn was prepared with a hollow spindle spinning machine, which using the SSW as the core material, the BC-PET and AN as the outer and inner wrapped yarns, respectively. The wrapping numbers was set at 8.0turns/cm for the produced metal composite yarns. Furthermore, a type of plated knitted fabric was designed and produced by using the automatic jacquard knitting machine. The plated knitted fabric presents the BC-PET/AN/SSW metal composite yarn on the knitted fabric face and the crisscross-section polyester (CSP on the knit back. The effect of lamination numbers and angles on the electromagnetic shielding effectiveness (EMSE were discussed in this study. EMSE measurement showed that the lamination angles will influence the EMSE, but not affect the air permeability. Finally, a novel EM shielding socks was designed with the produced plated knitted fabric. Finally, the performance of thermal resistance and evaporation resistance was also test usingThe sweating guarded hot plate apparatus.

  9. Fabrication of combined-scale nano- and microfluidic polymer systems using a multilevel dry etching, electroplating and molding process

    DEFF Research Database (Denmark)

    Tanzi, Simone; Østergaard, Peter Friis; Matteucci, Marco

    2012-01-01

    Microfabricated single-cell capture and DNA stretching devices have been produced by injection molding. The fabrication scheme employed deep reactive ion etching in a silicon substrate, electroplating in nickel and molding in cyclic olefin polymer. This work proposes technical solutions to fabric......Microfabricated single-cell capture and DNA stretching devices have been produced by injection molding. The fabrication scheme employed deep reactive ion etching in a silicon substrate, electroplating in nickel and molding in cyclic olefin polymer. This work proposes technical solutions...... to fabrication challenges associated with chip sealing and demolding of polymer high-volume replication methods. UV-assisted thermal bonding was found to ensure a strong seal of the microstructures in the molded part without altering the geometry of the channels. In the DNA stretching device, a low aspect ratio...... nanoslit (1/200) connecting two larger micro-channels was used to stretch a 168.5 kbp DNA molecule, while in the other device single-HeLa cells were captured against a micro-aperture connecting two larger microfluidic channels. Different dry etching processes have been investigated for the master...

  10. Fabrication of CoZn alloy nanowire arrays: Significant improvement in magnetic properties by annealing process

    International Nuclear Information System (INIS)

    Koohbor, M.; Soltanian, S.; Najafi, M.; Servati, P.

    2012-01-01

    Highlights: ► Increasing the Zn concentration changes the structure of NWs from hcp to amorphous. ► Increasing the Zn concentration significantly reduces the Hc value of NWs. ► Magnetic properties of CoZn NWs can be significantly enhanced by appropriate annealing. ► The pH of electrolyte has no significant effect on the properties of the NW arrays. ► Deposition frequency has considerable effects on the magnetic properties of NWs. - Abstract: Highly ordered arrays of Co 1−x Zn x (0 ≤ x ≤ 0.74) nanowires (NWs) with diameters of ∼35 nm and high length-to-diameter ratios (up to 150) were fabricated by co-electrodeposition of Co and Zn into pores of anodized aluminum oxide (AAO) templates. The Co and Zn contents of the NWs were adjusted by varying the ratio of Zn and Co ion concentrations in the electrolyte. The effect of the Zn content, electrodeposition conditions (frequency and pH) and annealing on the structural and magnetic properties (e.g., coercivity (Hc) and squareness (Sq)) of NW arrays were investigated using X-ray diffraction (XRD), scanning electron microscopy, electron diffraction, and alternating gradient force magnetometer (AGFM). XRD patterns reveal that an increase in the concentration of Zn ions of the electrolyte forces the hcp crystal structure of Co NWs to change into an amorphous phase, resulting in a significant reduction in Hc. It was found that the magnetic properties of NWs can be significantly improved by appropriate annealing process. The highest values for Hc (2050 Oe) and Sq (0.98) were obtained for NWs electrodeposited using 0.95/0.05 Co:Zn concentrations at 200 Hz and annealed at 575 °C. While the pH of electrolyte is found to have no significant effect on the structural and magnetic properties of the NW arrays, the electrodeposition frequency has considerable effects on the magnetic properties of the NW arrays. The changes in magnetic property of NWs are rooted in a competition between shape anisotropy and

  11. Fabrication of CoZn alloy nanowire arrays: Significant improvement in magnetic properties by annealing process

    Energy Technology Data Exchange (ETDEWEB)

    Koohbor, M. [Department of Physics, University of Kurdistan, Sanandaj (Iran, Islamic Republic of); Soltanian, S., E-mail: s.soltanian@gmail.com [Department of Physics, University of Kurdistan, Sanandaj (Iran, Islamic Republic of); Department of Electrical and Computer Engineering, University of British Columbia, Vancouver (Canada); Najafi, M. [Department of Physics, University of Kurdistan, Sanandaj (Iran, Islamic Republic of); Department of Physics, Hamadan University of Technology, Hamadan (Iran, Islamic Republic of); Servati, P. [Department of Electrical and Computer Engineering, University of British Columbia, Vancouver (Canada)

    2012-01-05

    Highlights: Black-Right-Pointing-Pointer Increasing the Zn concentration changes the structure of NWs from hcp to amorphous. Black-Right-Pointing-Pointer Increasing the Zn concentration significantly reduces the Hc value of NWs. Black-Right-Pointing-Pointer Magnetic properties of CoZn NWs can be significantly enhanced by appropriate annealing. Black-Right-Pointing-Pointer The pH of electrolyte has no significant effect on the properties of the NW arrays. Black-Right-Pointing-Pointer Deposition frequency has considerable effects on the magnetic properties of NWs. - Abstract: Highly ordered arrays of Co{sub 1-x}Zn{sub x} (0 {<=} x {<=} 0.74) nanowires (NWs) with diameters of {approx}35 nm and high length-to-diameter ratios (up to 150) were fabricated by co-electrodeposition of Co and Zn into pores of anodized aluminum oxide (AAO) templates. The Co and Zn contents of the NWs were adjusted by varying the ratio of Zn and Co ion concentrations in the electrolyte. The effect of the Zn content, electrodeposition conditions (frequency and pH) and annealing on the structural and magnetic properties (e.g., coercivity (Hc) and squareness (Sq)) of NW arrays were investigated using X-ray diffraction (XRD), scanning electron microscopy, electron diffraction, and alternating gradient force magnetometer (AGFM). XRD patterns reveal that an increase in the concentration of Zn ions of the electrolyte forces the hcp crystal structure of Co NWs to change into an amorphous phase, resulting in a significant reduction in Hc. It was found that the magnetic properties of NWs can be significantly improved by appropriate annealing process. The highest values for Hc (2050 Oe) and Sq (0.98) were obtained for NWs electrodeposited using 0.95/0.05 Co:Zn concentrations at 200 Hz and annealed at 575 Degree-Sign C. While the pH of electrolyte is found to have no significant effect on the structural and magnetic properties of the NW arrays, the electrodeposition frequency has considerable effects on

  12. Design and fabrication of substrates with microstructures for bio-applications through the modified optical disc process

    Science.gov (United States)

    Chiu, Kuo-Chi; Chang, Sheng-Li; Huang, Chu-Yu; Guan, Hann-Wen

    2011-05-01

    The modified optical disc process has been investigated and demonstrated to enable fast prototyping in fabricating molds and replicating substrates with various microstructures including micro-chambers and micro-channels. A disc-like microfluidic device was created and the testing results showed good performance in bonding and packaging. The switching of the nozzle-like micro-valve was also validated to work well. Furthermore, the relevant procedures of liquid samples loading, separating and mixing were also accomplished through food experiments.

  13. Direct-write PVDF nonwoven fiber fabric energy harvesters via the hollow cylindrical near-field electrospinning process

    Science.gov (United States)

    Liu, Z. H.; Pan, C. T.; Lin, L. W.; Huang, J. C.; Ou, Z. Y.

    2014-02-01

    One-dimensional piezoelectric nanomaterials have attracted great attention in recent years for their possible applications in mechanical energy scavenging devices. However, it is difficult to control the structural diameter, length, and density of these fibers fabricated by micro/nano-technologies. This work presents a hollow cylindrical near-field electrospinning (HCNFES) process to address production and performance issues encountered previously in either far-field electrospinning (FFES) or near-field electrospinning (NFES) processes. Oriented polyvinylidene fluoride (PVDF) fibers in the form of nonwoven fabric have been directly written on a glass tube for aligned piezoelectricity. Under a high in situ electrical poling field and strong mechanical stretching (the tangential speed on the glass tube collector is about 1989.3 mm s-1), the HCNFES process is able to uniformly deposit large arrays of PVDF fibers with good concentrations of piezoelectric β-phase. The nonwoven fiber fabric (NFF) is transferred onto a polyethylene terephthalate (PET) substrate and fixed at both ends using copper foil electrodes as a flexible textile-fiber-based PVDF energy harvester. Repeated stretching and releasing of PVDF NFF with a strain of 0.05% at 7 Hz produces a maximum peak voltage and current at 76 mV and 39 nA, respectively.

  14. Direct-write PVDF nonwoven fiber fabric energy harvesters via the hollow cylindrical near-field electrospinning process

    International Nuclear Information System (INIS)

    Liu, Z H; Pan, C T; Ou, Z Y; Lin, L W; Huang, J C

    2014-01-01

    One-dimensional piezoelectric nanomaterials have attracted great attention in recent years for their possible applications in mechanical energy scavenging devices. However, it is difficult to control the structural diameter, length, and density of these fibers fabricated by micro/nano-technologies. This work presents a hollow cylindrical near-field electrospinning (HCNFES) process to address production and performance issues encountered previously in either far-field electrospinning (FFES) or near-field electrospinning (NFES) processes. Oriented polyvinylidene fluoride (PVDF) fibers in the form of nonwoven fabric have been directly written on a glass tube for aligned piezoelectricity. Under a high in situ electrical poling field and strong mechanical stretching (the tangential speed on the glass tube collector is about 1989.3 mm s −1 ), the HCNFES process is able to uniformly deposit large arrays of PVDF fibers with good concentrations of piezoelectric β-phase. The nonwoven fiber fabric (NFF) is transferred onto a polyethylene terephthalate (PET) substrate and fixed at both ends using copper foil electrodes as a flexible textile-fiber-based PVDF energy harvester. Repeated stretching and releasing of PVDF NFF with a strain of 0.05% at 7 Hz produces a maximum peak voltage and current at 76 mV and 39 nA, respectively. (paper)

  15. A Review of the Effect of Processing Variables on the Fabrication of Electro spun Nano fibers for Drug Delivery Applications

    International Nuclear Information System (INIS)

    Pillay, V.; Dott, C.; Choonara, Y.E.; Tyagi, Ch.; Tomar, L.; Kumar, P.; Toit, L.C.D.; Ndesendo, V.M.K.

    2013-01-01

    Electro spinning is a fast emerging technique for producing ultrafine fibers by utilizing electrostatic repulsive forces. The technique has gathered much attention due to the emergence of nano technology that sparked worldwide research interest in nano materials for their preparation and application in biomedicine and drug delivery. Electro spinning is a simple, adaptable, cost-effective, and versatile technique for producing nano fibers. For effective and efficient use of the technique, several processing parameters need to be optimized for fabricating polymeric nano fibers. The nano fiber morphology, size, porosity, surface area, and topography can be refined by varying these parameters. Such flexibility and diversity in nano fiber fabrication by electro spinning has broadened the horizons for widespread application of nano fibers in the areas of drug and gene delivery, wound dressing, and tissue engineering. Drug-loaded electro spun nano fibers have been used in implants, transdermal systems, wound dressings, and as devices for aiding the prevention of post surgical abdominal adhesions and infection. They show great promise for use in drug delivery provided that one can confidently control the processing variables during fabrication. This paper provides a concise incursion into the application of electro spun nano fibers in drug delivery and cites pertinent processing parameters that may influence the performance of the nano fibers when applied to drug delivery.

  16. Density improvement of Li{sub 2}TiO{sub 3} pebbles fabricated by wet process

    Energy Technology Data Exchange (ETDEWEB)

    Tsuchiya, K.; Kawamura, H. [Japan Atomic Energy Research Inst., Oarai, Ibaraki (Japan). Oarai Research Establishment; Fuchinoue, K.; Sawada, H.; Watarumi, K.

    1998-03-01

    Lithium titanate (Li{sub 2}TiO{sub 3}) has attracted the attention of many researchers from a point of tritium recovery at low temperature, chemical stability, etc.. The application of small Li{sub 2}TiO{sub 3} sphere has been proposed in some designs of fusion blanket. On the other hand, the wet process is most advantageous as the fabrication method of Li{sub 2}TiO{sub 3} pebbles from a point of mass production, and of reprocessing necessary for effective use of resources and reduction of radioactive wastes. In the preliminary fabrication test, density of Li{sub 2}TiO{sub 3} pebbles was about 40%T.D.. Therefore, in this study, density improvement tests and preliminary characterization of Li{sub 2}TiO{sub 3} pebbles by wet process were performed, noting the aging condition and sintering condition in the fabrication process of the gel-spheres. This study yielded Li{sub 2}TiO{sub 3} pebbles in target range of 80-85%T.D.. (author)

  17. Fabrication of AZ31/MWCNTs Surface Metal Matrix Composites by Friction Stir Processing: Investigation of Microstructure and Mechanical Properties

    Science.gov (United States)

    Arab, Seyed Mohammad; Zebarjad, Seyed Mojtaba; Jahromi, Seyed Ahmad Jenabali

    2017-11-01

    The surface metal matrix composites of AZ31 Mg alloy reinforced with multiwall carbon nanotubes (MWCNTs) have been fabricated through the friction stir processing by a conventional and two stepped tools. The microstructure and mechanical properties of fabricated composites were studied by optical and electron microscopy, microhardness and tensile tests, respectively. The processing has developed a fine-grain structure along with good distribution of reinforcements. The hardness and tensile strength of fabricated MWCNT/AZ31 composites are generally higher than as-received and FSPed samples. The accumulative effect of grain refinement and reinforcing nanotubes is assumed to be the reason for increasing the ductility after friction stir processing. The hardness is nearly doubled for FSPed samples and some more for nanocomposites compared with the as-received sample. The elongation of nanocomposites is about two times greater than that of the as-rolled sample. The speed ratio, pass number and CNT amount are three important factors influencing the resulting microstructure and mechanical properties. The stepped tools also give a more uniform distribution of reinforcement and higher grain refinement.

  18. Microstructures and mechanical properties of Co-29Cr-6Mo alloy fabricated by selective laser melting process for dental applications.

    Science.gov (United States)

    Takaichi, Atsushi; Suyalatu; Nakamoto, Takayuki; Joko, Natsuka; Nomura, Naoyuki; Tsutsumi, Yusuke; Migita, Satoshi; Doi, Hisashi; Kurosu, Shingo; Chiba, Akihiko; Wakabayashi, Noriyuki; Igarashi, Yoshimasa; Hanawa, Takao

    2013-05-01

    The selective laser melting (SLM) process was applied to a Co-29Cr-6Mo alloy, and its microstructure, mechanical properties, and metal elution were investigated to determine whether the fabrication process is suitable for dental applications. The microstructure was evaluated using scanning electron microscopy with energy-dispersed X-ray spectroscopy (SEM-EDS), X-ray diffractometry (XRD), and electron back-scattered diffraction pattern analysis. The mechanical properties were evaluated using a tensile test. Dense builds were obtained when the input energy of the laser scan was higher than 400 J mm⁻³, whereas porous builds were formed when the input energy was lower than 150 J mm⁻³. The microstructure obtained was unique with fine cellular dendrites in the elongated grains parallel to the building direction. The γ phase was dominant in the build and its preferential orientation was confirmed along the building direction, which was clearly observed for the builds fabricated at lower input energy. Although the mechanical anisotropy was confirmed in the SLM builds due to the unique microstructure, the yield strength, UTS, and elongation were higher than those of the as-cast alloy and satisfied the type 5 criteria in ISO22764. Metal elution from the SLM build was smaller than that of the as-cast alloy, and thus, the SLM process for the Co-29Cr-6Mo alloy is a promising candidate for fabricating dental devices. Copyright © 2013 Elsevier Ltd. All rights reserved.

  19. [Energy dispersive spectrum analysis of surface compositions of selective laser melting cobalt-chromium alloy fabricated by different processing parameters].

    Science.gov (United States)

    Qian, Liang; Zeng, Li; Wei, Bin; Gong, Yao

    2015-06-01

    To fabricate selective laser melting cobalt-chromium alloy samples by different processing parameters, and to analyze the changes of energy dispersive spectrum(EDS) on their surface. Nine groups were set up by orthogonal experimental design according to different laser powers,scanning speeds and powder feeding rates(laser power:2500-3000 W, scanning speed: 5-15 mm/s, powder feeding rate: 3-6 r/min). Three cylinder specimens(10 mm in diameter and 3 mm in thickness) were fabricated in each group through Rofin DL 035Q laser cladding system using cobalt-chromium alloy powders which were developed independently by our group.Their surface compositions were then measured by EDS analysis. Results of EDS analysis of the 9 groups fabricated by different processing parameters(Co:62.98%-67.13%,Cr:25.56%-28.50%,Si:0.49%-1.23%) were obtained. They were similar to the compositions of cobalt-chromium alloy used in dental practice. According to EDS results, the surface compositions of the selective laser melting cobalt-chromium alloy samples are stable and controllable, which help us gain a preliminary sight into the range of SLM processing parameters. Supported by "973" Program (2012CB910401) and Research Fund of Science and Technology Committee of Shanghai Municipality (12441903001 and 13140902701).

  20. Control structures design for fossil power station units; Diseno de estructuras de control para unidades termoelectricas

    Energy Technology Data Exchange (ETDEWEB)

    Palomares Gonzalez, Daniel; Ricano Castillo, Juan Manuel [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1989-12-31

    In this paper are designed an analyzed the control ties of a 300MW fossil unit at different operation levels. The design and analysis were developed on an operation range of 50% to 100% load. The main control ties were studied among which are the feedwater flow, the superheating zone temperatures and the generated output. The technique used for the design is the decomposition in singular values (DSV) of the plant transference matrix. This is a recent technique that permits finding the most important interactions among output-input variables, over a significative frequencies range for the transference matrix of the plant. For this purpose utilizes the control properties of the transference matrix, such as: control effort, output-input interaction and ruggedness with respect to uncertainties. The control structures obtained were tested in a digital model of a fossil plant unit. A comparison study of both structures (original and modified) showed enhancement in the performance of the power plant with modified structure. [Espanol] En este trabajo se disenan y analizan los lazos de control de una unidad termoelectrica de 300 MW, a diferentes niveles de operacion. El diseno y analisis se desarrollo sobre un rango de operacion de 50 a 100 por ciento de carga. Se estudiaron los principales lazos de control entre los que se encuentran el flujo de agua de alimentacion, las temperaturas de la zona de sobrecalentamiento y la potencia generada. La tecnica utilizada para el diseno es la descomposicion en valores singulares (DVS) de la matriz de transferencia de la planta. Esta es una tecnica reciente que permite encontrar las interacciones mas importantes entre variables entrada-salida, sobre un rango de frecuencias significativas para la matriz de transferencia de la planta. Utiliza para ello las propiedades de control de la matriz de transferencia, como son: esfuerzo de control, interaccion entrada-salida y robustez con respecto a incertidumbres. Las estructuras de control

  1. Restart of the chemical preparation process for the fabrication of ZnO varistors for ferroelectric neutron generator power supplies

    International Nuclear Information System (INIS)

    Lockwood, Steven John

    2005-01-01

    To date, all varistors used in ferroelectric neutron generators have been supplied from a single, proprietary source, General Electric Corporate Research and Development (GE CR and D). To protect against the vulnerability of a single source, Sandia initiated a program in the early 1980's to develop a second source for this material. A chemical preparation process for making homogeneous, high purity ZnO-based varistor powder was generated, scaled to production quantities, and transferred to external suppliers. In 1992, the chem-prep varistor program was suspended when it appeared there was sufficient inventory of GE CR and D material to supply ferroelectric neutron generator production for many years. In 1999, neutron generator production schedules increased substantially, resulting in a predicted exhaustion of the existing supply of varistor material within five years. The chem-prep program was restarted in January, 2000. The goals of the program were to (1) duplicate the chem-prep powder synthesis process that had been qualified for WR production, (2) demonstrate sintered billets from the chem-prep powder met requirements, (3) develop a process for rod fabrication and demonstrate that all component specifications could be met, and (4) optimize the process from powder synthesis through component fabrication for full-scale production. The first three of these goals have been met and are discussed in this report. A facility for the fabrication of production quantities of chem-prep powder has been established. All batches since the restart have met compositional requirements, but differences in sintering behavior between the original process and the restarted process were noted. Investigation into the equipment, precipitant stoichiometry, and powder processing procedures were not able to resolve the discrepancies. It was determined that the restarted process, which incorporated Na doping for electrical stability (a process that was not introduced until the end of the

  2. Development of Unified Fabrication Process and Testing of MEMS Based Comb and Crab Type Capacitive Accelerometers for Navigational Applications

    Directory of Open Access Journals (Sweden)

    R. K. Bhan

    2016-08-01

    Full Text Available MEMS based accelerometers have already penetrated defense programs including navigation control in addition to their usual deployment in automotive, consumer and industrial markets because of their improved reliability, accuracy and excellent price performance. This paper discussed about the fabrication and testing of single axis capacitive accelerometer structures based on change in area (comb-type and change in gap (Crab type sensing principles. The accelerometers are designed for ±30 g acceleration range. A common fabrication process flow is designed for the fabrication of both types of accelerometers that are fabricated by using a three mask dissolved wafer process (DWP. Both the accelerometers showed a scale factor sensitivity of >60 mV/g at ±1 g flip test. Vibration and sensitivity testing at higher frequency was conducted on shaker table using a half sine wave shock (HSWS of 2 ms. Using HSWS test, a sensitivity in the range of ~60 mV/g was obtained for both comb or crab type structures in the 0-30 g range. It can be further tuned upto 100 mV/g by increasing the gain of the capacitance Read Out Integrated Circuit (ROIC. However, performance of the comb type of accelerometers gets affected in – 30 g to – 0 g range due to deep boron diffusion induced residual stress. The crab accelerometers showed almost linear (nonlinearity:<3 % FS behavior in the whole ±30 g range. Other tests like bias stability, bandwidth, bias temperature coefficient etc. indicate that devices are fully functional. All these observations validate our design and unified process.

  3. Luminescence and scintillation enhancement of Y2O3:Tm transparent ceramic through post-fabrication thermal processing

    International Nuclear Information System (INIS)

    Chapman, M.G.; Marchewka, M.R.; Roberts, S.A.; Schmitt, J.M.; McMillen, C.; Kucera, C.J.; DeVol, T.A.; Ballato, J.; Jacobsohn, L.G.

    2015-01-01

    The effects of post-fabrication thermal processing in O 2 flux on the luminescence and scintillation of a Y 2 O 3 :Tm transparent ceramic were investigated. The results showed that the strategy of post-fabrication processing can be beneficial to the performance of the ceramics, depending on the cumulative processing time. After the first hour of processing, about 40% enhancement in the luminescence output together with about 20% enhancement in the scintillation light yield were obtained. The enhancements were tentatively assigned to the incorporation of oxygen into vacancy sites. Longer cumulative processing times lead to the incorporation of oxygen as interstitials that is detrimental to scintillation light yield but not to luminescence output. This work also revealed that thermoluminescence measurements are a useful tool to predict scintillation light yield of Y 2 O 3 :Tm. - Highlights: • Scintillation and PL enhancement of transparent ceramics through thermal processing. • First thermoluminescence measurements of Y 2 O 3 :Tm above room temperature. • Observation of correlation between TL and scintillation light yield results

  4. Fabrication process for CMUT arrays with polysilicon electrodes, nanometre precision cavity gaps and through-silicon vias

    Science.gov (United States)

    Due-Hansen, J.; Midtbø, K.; Poppe, E.; Summanwar, A.; Jensen, G. U.; Breivik, L.; Wang, D. T.; Schjølberg-Henriksen, K.

    2012-07-01

    Capacitive micromachined ultrasound transducers (CMUTs) can be used to realize miniature ultrasound probes. Through-silicon vias (TSVs) allow for close integration of the CMUT and read-out electronics. A fabrication process enabling the realization of a CMUT array with TSVs is being developed. The integrated process requires the formation of highly doped polysilicon electrodes with low surface roughness. A process for polysilicon film deposition, doping, CMP, RIE and thermal annealing that resulted in a film with sheet resistance of 4.0 Ω/□ and a surface roughness of 1 nm rms has been developed. The surface roughness of the polysilicon film was found to increase with higher phosphorus concentrations. The surface roughness also increased when oxygen was present in the thermal annealing ambient. The RIE process for etching CMUT cavities in the doped polysilicon gave a mean etch depth of 59.2 ± 3.9 nm and a uniformity across the wafer ranging from 1.0 to 4.7%. The two presented processes are key processes that enable the fabrication of CMUT arrays suitable for applications in for instance intravascular cardiology and gastrointestinal imaging.

  5. Fabrication process for CMUT arrays with polysilicon electrodes, nanometre precision cavity gaps and through-silicon vias

    International Nuclear Information System (INIS)

    Due-Hansen, J; Poppe, E; Summanwar, A; Jensen, G U; Breivik, L; Wang, D T; Schjølberg-Henriksen, K; Midtbø, K

    2012-01-01

    Capacitive micromachined ultrasound transducers (CMUTs) can be used to realize miniature ultrasound probes. Through-silicon vias (TSVs) allow for close integration of the CMUT and read-out electronics. A fabrication process enabling the realization of a CMUT array with TSVs is being developed. The integrated process requires the formation of highly doped polysilicon electrodes with low surface roughness. A process for polysilicon film deposition, doping, CMP, RIE and thermal annealing that resulted in a film with sheet resistance of 4.0 Ω/□ and a surface roughness of 1 nm rms has been developed. The surface roughness of the polysilicon film was found to increase with higher phosphorus concentrations. The surface roughness also increased when oxygen was present in the thermal annealing ambient. The RIE process for etching CMUT cavities in the doped polysilicon gave a mean etch depth of 59.2 ± 3.9 nm and a uniformity across the wafer ranging from 1.0 to 4.7%. The two presented processes are key processes that enable the fabrication of CMUT arrays suitable for applications in for instance intravascular cardiology and gastrointestinal imaging. (paper)

  6. Fabrication of polycrystalline diamond refractive X-ray lens by femtosecond laser processing

    Energy Technology Data Exchange (ETDEWEB)

    Kononenko, T.V.; Ralchenko, V.G.; Ashkinazi, E.E.; Konov, V.I. [General Physics Institute of Russian Academy of Sciences, Moscow (Russian Federation); National Research Nuclear University ' ' MEPhI' ' , Moscow (Russian Federation); Polikarpov, M.; Ershov, P. [Immanuel Kant Baltic Federal University, Functional Nanomaterials, Kaliningrad (Russian Federation); Kuznetsov, S.; Yunkin, V. [Institute of Microelectronics Technology RAS, Chernogolovka, Moscow region (Russian Federation); Snigireva, I. [European Synchrotron Radiation Facility, Grenoble (France)

    2016-03-15

    X-ray planar compound refractive lenses were fabricated from a polycrystalline diamond plate grown by chemical vapor deposition, by precise through cutting with femtosecond laser pulses. The lens geometry and the surface morphology were investigated with optical and scanning electron microscopy, while the material structure modification was analyzed by Raman spectroscopy. The results of the preliminary lens test at 9.25-keV X-rays are presented. (orig.)

  7. Continuous process of powder production for MOX fuel fabrication according to ''granat'' technology

    International Nuclear Information System (INIS)

    Morkovnikov, V.E.; Raginskiy, L.S.; Pavlinov, A.P.; Chernov, V.A.; Revyakin, V.V.; Varykhanov, V.S.; Revnov, V.N.

    2000-01-01

    During last years the problem of commercial MOX fuel fabrication for nuclear reactors in Russia was solved in a number of directions. The paper deals with the solution of the problem of creating a continuous pilot plant for the production of MOX fuel powders on the basis of the home technology 'Granat', that was tested before on a small-scale pilot-commercial batch-operated plant of the same name and confirmed good results. (authors)

  8. Fabrication of polycrystalline diamond refractive X-ray lens by femtosecond laser processing

    International Nuclear Information System (INIS)

    Kononenko, T.V.; Ralchenko, V.G.; Ashkinazi, E.E.; Konov, V.I.; Polikarpov, M.; Ershov, P.; Kuznetsov, S.; Yunkin, V.; Snigireva, I.

    2016-01-01

    X-ray planar compound refractive lenses were fabricated from a polycrystalline diamond plate grown by chemical vapor deposition, by precise through cutting with femtosecond laser pulses. The lens geometry and the surface morphology were investigated with optical and scanning electron microscopy, while the material structure modification was analyzed by Raman spectroscopy. The results of the preliminary lens test at 9.25-keV X-rays are presented. (orig.)

  9. Photonic properties of hybrid colloidal crystals fabricated by a rapid dip-coating process.

    Science.gov (United States)

    Deleuze, C; Sarrat, B; Ehrenfeld, F; Perquis, S; Derail, C; Billon, L

    2011-06-14

    The enhancement of the capillarity fabrication of well-ordered two-dimensional (2D) and three-dimensional (3D) opal photonic crystal is described herein. The quality enhancement and the reduction of the fabrication time are improved by using core@soft adhesive shell (Silica@PolyButylAcrylate) particles dispersed in an organic solvent with a high boiling point. The hybridization by an elastomeric corona polymer, grafted from the SiO(2) surface, has offered adhesive properties naturally tunable by changing the polymer state from a solvated to a dry one. Such properties involve drastic changes of the self-assembly behavior and qualities. Their use, as elementary building blocks, for colloidal crystal fabrication have required a high withdrawal rate (up to 4000 μm s(-1)), i.e. involving a three order of magnitude reduction in time compared to a classic vertical deposition method (1 to 10 μm s(-1)) and a good control/prediction of the coating thickness can be tuned by varying the withdrawal rate and the particle concentration. In addition, an analysis of the 2D synthetic iridescence of the hybrid photonic crystal was performed under white light, revealing the adhesive shell bridge influence on the dissipation energy of cracks linked to the crystal quality and the photonic properties. This journal is © the Owner Societies 2011

  10. Large-scale fabrication of In2S3 porous films via one-step hydrothermal process.

    Science.gov (United States)

    Chen, Fei; Deng, Dan; Lei, Yinlin

    2013-10-01

    Large-scale indium sulfide (In2S3) porous films were fabricated via a facile one-step and non-template hydrothermal process using L-cysteine as a capping agent. The impact of reaction conditions such as reaction time, temperatures, and capping agents on the synthesis of the In2S3 porous films were studied. The morphology, structure, and phase composition of In2S3 porous films were characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), and transmission electron microscopy (TEM). The formation process and the optical property of the In2S3 porous films were also evaluated.

  11. 3D Viscoelastic Finite Element Modelling of Polymer Flow in the Fiber Drawing Process for Microstructured Polymer Optical Fiber Fabrication

    DEFF Research Database (Denmark)

    Fasano, Andrea; Rasmussen, Henrik K.; Marín, J. M. R.

    2015-01-01

    The process of drawing an optical fiber from a polymer preform is still not completely understood,although it represents one of the most critical steps in the process chain for the fabrication of microstructuredpolymer optical fibers (mPOFs). Here we present a new approach for the numerical...... modelling of the fiber drawingprocess using a fully three-dimensional and time-dependent finite element method, giving significant insightinto this widely spread mPOF production technique. Our computational predictions are physically based on theviscoelastic fluid dynamics of polymers. Until now...

  12. Fabrication of a Sludge-Conditioning System for processing legacy wastes from the Gunite and Associated Tanks

    International Nuclear Information System (INIS)

    Randolph, J.D.; Lewis, B.E.; Farmer, J.R.; Johnson, M.A.

    2000-01-01

    The Sludge Conditioning System (SCS) for the Gunite and Associated Tanks (GAATs) is designed to receive, monitor, characterize and process legacy waste materials from the South Tank Farm tanks in preparation for final transfer of the wastes to the Melton Valley Storage Tanks (MVSTs), which are located at Oak Ridge National Laboratory. The SCS includes (1) a Primary Conditioning System (PCS) Enclosure for sampling and particle size classification, (2) a Solids Monitoring Test Loop (SMTL) for slurry characterization, (3) a Waste Transfer Pump to retrieve and transfer waste materials from GAAT consolidation tank W-9 to the MVSTs, (4) a PulsAir Mixing System to provide mixing of consolidated sludges for ease of retrieval, and (5) the interconnecting piping and valving. This report presents the design, fabrication, cost, and fabrication schedule information for the SCS

  13. ''Fabrice'' process for reconstituting experimental rods in a hot cell from pre-irradiated rods in power reactors

    International Nuclear Information System (INIS)

    Houdaille, B.; Vignesoult, N.; Atabek, R.

    1981-11-01

    The Fabrice process for the ''hot cell refabrication'' of small rods from very long irradiated fuel elements was developed by the CEA, particularly to enable parametric studies to be carried out on the behaviour under irradiation of rods from power stations. This technique, although requiring intricate operations in a hot cell with specially adapted equipment and a very experienced personnel, enables (1) a significant saving to be made compared with the pre-irradiation of new rods and (2) affords a virtually unlimited choice of rod sections irradiated in a power reactor for parametric irradiations. Tests have shown that the initial characteristics of the sample rod are not modified and that the behaviour under irradiation of whole non-refabricated rods and Fabrice rods with the same initial characteristics is identical, for a local specific burn-up under 40,000 MWd/t, vis-a-vis the fuel cladding interaction phenomenon [fr

  14. The fabrication process of ceramic grade UO2 powder via fluorid system AUC and the treatment on AUC precipitation filtrate

    International Nuclear Information System (INIS)

    Liu Jinhong; Xu Kui; Li Zhiwan; Yi Wei; Tang Yueming; Li Guangrong; Lei Maolin; Cui Chuanjiang

    2006-10-01

    It is described about the technology of fabricating AUC powder by Circum-fluence Precipitation Reactor with Gas (CPRG) from UF 6 hydrolyzed liquid, manufacturing nuclear pure ceramic grade UO 2 powder via fluorid system AUC process with fluidized bed method, recovering U(VI) with ion exchange resin, depositing fluorin in an outflow of effusion wastewater from the ion exchange using calces. The primary control parameters on the fabricating AUC powder is study, it is discussed to character difference of AUC powder between fluorid system and nitrate. Result show that the composing the manufacture AUC powder is invariable by CORG, and that the AUC quality is consistent, and that by decomposition and reduction of AUC and stabilization of UO 2 powder with fluidized bed, through optimum technological parameters, the excellent UO 2 powder is obtained on the quality. (authors)

  15. Design and simulation of a process of seawater desalination (MED) using the residual heat of a PBMR nuclear power plant; Diseno y simulacion de un proceso de desalinizacion de agua de mar (MED) utilizando el calor residual de una planta nucleoelectrica PBMR

    Energy Technology Data Exchange (ETDEWEB)

    Valle H, Julio; Morales S, J.B. [UNAM, DEPFI Campus Morelos, Jiutepec, Morelos (Mexico)]. e-mail: jms0620@yahoo.com

    2008-07-01

    In the present work it is demonstrated as the thermodynamic recuperative Brayton cycle with which operates a nuclear power plant type PBMR (Pebble Bed Modular Reactor) it allows to use the residual heat, removed in the coolers of the compression stage of the system, to produce vapor and to desalt seawater. The desalination process selected, starting from its operation characteristics and the derived advantages of them using nuclear heat, it the one of Multi-Effect Distillation, MED for its abbreviations in English, which described and it is justified to detail. This distillation process widely studied, allows us to use water vapor pressurized to temperatures between 70 and 110 C like energy source to evaporate the seawater in the first stage or effect of the process. The relatively low temperatures with which the vapor takes place of feeding to the process is it makes to the plant PBMR ideal for desalination of seawater, since does not require majors modifications to its design its operation, and on the contrary it allows to use the heat that previously was rejected, to produce the vapor. In this work an unit MED of six effects is designed, which undergoes a successive fall of pressure in each of them. Once obtained the agreed design to the conditions of operation of PBMR plant, it was model mathematically the MED process, including the coupling stage with the reactor coolers. The mathematical model was obtained by means of differential equations of mass balance and energy in the system, and with this it was implemented in SIMULINK a model equivalent to the MED process which is interconnected to the simulator coolers of the PBMR plant, constructed previously. One ran the program being obtained the results that are reported at the end of this article. (Author)

  16. Holographic Read-Only Memory Fabricated by Deposition of Reflector after Writing Process with Aromatic Photopolymer Recording Layer

    Science.gov (United States)

    Ando, Toshio; Masaki, Kazuyoshi; Shimizu, Takehiro

    2010-08-01

    The deposition of reflector after writing (DRAW) process has been proposed for the fabrication of reflective-type holographic read-only memories. In the DRAW process, a reflector is deposited on a recording medium after signal writing, resulting in the reduction of noise holograms written by reflected beams from a reflector in the write process. Significant improvements are experimentally confirmed in read and write (R/W) performances in DRAW-processed holographic media. The combination of the DRAW process and an aromatic photopolymer recording material realizes low noise, high signal-to-noise ratio, and low symbol error rate characteristics at large multiplexing numbers up to 1020. In conventional reflective-type holographic media, ghost noise is superimposed on the readout signal, causing deterioration in R/W characteristics. The wave vector analyses clarify the mechanism by which the noise holograms are written and ghost noise is superimposed on the signal beam in the conventional media.

  17. Scalable processes for fabricating non-volatile memory devices using self-assembled 2D arrays of gold nanoparticles as charge storage nodes.

    Science.gov (United States)

    Muralidharan, Girish; Bhat, Navakanta; Santhanam, Venugopal

    2011-11-01

    We propose robust and scalable processes for the fabrication of floating gate devices using ordered arrays of 7 nm size gold nanoparticles as charge storage nodes. The proposed strategy can be readily adapted for fabricating next generation (sub-20 nm node) non-volatile memory devices.

  18. Developing and verifying design and operational criteria for the active sludge process involving staggered feed with the elimination of nitrogen; Desarrollo y verificacion de criterios de diseno y oporacion para el proceso de fangos activos de alimentacion escalonada con eliminacion de nitrogeno

    Energy Technology Data Exchange (ETDEWEB)

    Larrea, L.; Larrea, A.; Ayesa, E.; Rodrigo, J. C.

    2000-07-01

    This study focused on the staggered feed process with three denitrification-nitrification reactor phases. In the first place, criteria for the optimum selection of design parameters were developed using simulations based on mathematical models of the process and efficient operational strategies were suggested. The results of the simulation were then verified by means of tests in a pilot plant. In regard to the design parameters, the simulation studies showed that the optimum in-flow to the three anoxic reactors lies within the range 40-40-20% to 33-33-34%, depending on the characteristics of the waste water and the requirements of the effluent. These latter two conditions and, therefore, the distribution of the inflow, determine the volumes of the aerobic and anoxic reactors. The operating strategy proposed consists in reducing the concentration of dissolved oxygen in the first two aerobic reactors and using optional areas in the last D-N stage of the process. The experimental results obtained confirmed the validity of the design and operational criteria that had been developed. Finally, it was found that if IWA model no. 1 is appropriately calibrated, it has a great capacity for predicting the behaviour of the staggered feed process. (Author) 12 refs.

  19. Influence of the fabrication process parameters on microstructures and mechanical properties of 10Cr-1Mo ODS steel

    International Nuclear Information System (INIS)

    Jin, Hyun Ju; Kim, Ki Baik; Choi, Byoung Kwon; Kang, Suk Hoon; Noh, Sang Hoon; Kim, Ga Eon; Kim, Tae Kyu

    2016-01-01

    Oxide dispersion strengthened (ODS) FM steels have been developed as the most promising core structural material for high- temperature components operating in severe environments such as nuclear fusion and fission systems owing to its excellent elevated temperature strength and radiation resistance stemming from the addition of extremely thermally stable oxide particles dispersed in a ferritic/martensitic matrix. To realize the structural components such as plates, sheets and tubes in SFR, the development of manufacturing processes is an essential issue for the ODS FM steel. While the ODS steel has superior radiation resistance and high temperature strength, in comparison with the existing commercial steels, it is difficult for the ODS steel to obtain sufficient workability for the fabrication due to high hardness and low ductility at room temperature, meaning that the manufacturing of the ODS plate including cladding tube can be complicated by the low cold workability. In order to prevent the ODS steel from any damage during the manufacturing process, thus, the introduction of intermediate heat treatments between cold rolling processes is necessary. This study investigates effects of the fabrication process parameters such as the cold working ratio, the intermediate and final heat treatments on the microstructure and mechanical properties of 10Cr-1Mo ODS steel. In an effort to optimize the manufacturing route of the ODS FM steel, the microstructural and mechanical evolutions for the ODS plate manufactured by a control of the fabrication process parameters were evaluated in the present study. In the present study, the effect of a cold rolling and intermediate heat treatments on microstructures and mechanical properties of 10Cr-1Mo FM ODS steel were investigated. During the manufacturing route the hardness measurements remained below the critical value of 400 Hv. Intermediate heat treatment with slow cooling led to a softened ferritic structures which can be further

  20. Comparative Study of Laboratory-Scale and Prototypic Production-Scale Fuel Fabrication Processes and Product Characteristics

    International Nuclear Information System (INIS)

    2014-01-01

    An objective of the High Temperature Gas Reactor fuel development and qualification program for the United States Department of Energy has been to qualify fuel fabricated in prototypic production-scale equipment. The quality and characteristics of the tristructural isotropic coatings on fuel kernels are influenced by the equipment scale and processing parameters. Some characteristics affecting product quality were suppressed while others have become more significant in the larger equipment. Changes to the composition and method of producing resinated graphite matrix material has eliminated the use of hazardous, flammable liquids and enabled it to be procured as a vendor-supplied feed stock. A new method of overcoating TRISO particles with the resinated graphite matrix eliminates the use of hazardous, flammable liquids, produces highly spherical particles with a narrow size distribution, and attains product yields in excess of 99%. Compact fabrication processes have been scaled-up and automated with relatively minor changes to compact quality to manual laboratory-scale processes. The impact on statistical variability of the processes and the products as equipment was scaled are discussed. The prototypic production-scale processes produce test fuels that meet fuel quality specifications.

  1. Fabrication of Li{sub 2}TiO{sub 3} pebbles by a freeze drying process

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Sang-Jin, E-mail: lee@mokpo.ac.kr [Department of Advanced Materials Science and Engineering, Mokpo National University, Muan 534-729 (Korea, Republic of); Park, Yi-Hyun [National Fusion Research Institute, Daejeon 305-806 (Korea, Republic of); Yu, Min-Woo [Department of Advanced Materials Science and Engineering, Mokpo National University, Muan 534-729 (Korea, Republic of)

    2013-11-15

    Li{sub 2}TiO{sub 3} pebbles were successfully fabricated by using a freeze drying process. The Li{sub 2}TiO{sub 3} slurry was prepared using a commercial powder of particle size 0.5–1.5 μm and the pebble pre-form was prepared by dropping the slurry into liquid nitrogen through a syringe needle. The droplets were rapidly frozen, changing their morphology to spherical pebbles. The frozen pebbles were dried at −10 °C in vacuum. To make crack-free pebbles, some glycerin was employed in the slurry, and long drying time and a low vacuum condition were applied in the freeze drying process. In the process, the solid content in the slurry influenced the spheroidicity of the pebble green body. The dried pebbles were sintered at 1200 °C in an air atmosphere. The sintered pebbles showed almost 40% shrinkage. The sintered pebbles revealed a porous microstructure with a uniform pore distribution and the sintered pebbles were crushed under an average load of 50 N in a compressive strength test. In the present study, a freeze drying process for fabrication of spherical Li{sub 2}TiO{sub 3} pebbles is introduced. The processing parameters, such as solid content in the slurry and the conditions of freeze drying and sintering, are also examined.

  2. Comparative Study of Laboratory-Scale and Prototypic Production-Scale Fuel Fabrication Processes and Product Characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Douglas W. Marshall

    2014-10-01

    An objective of the High Temperature Gas Reactor fuel development and qualification program for the United States Department of Energy has been to qualify fuel fabricated in prototypic production-scale equipment. The quality and characteristics of the tristructural isotropic coatings on fuel kernels are influenced by the equipment scale and processing parameters. Some characteristics affecting product quality were suppressed while others have become more significant in the larger equipment. Changes to the composition and method of producing resinated graphite matrix material has eliminated the use of hazardous, flammable liquids and enabled it to be procured as a vendor-supplied feed stock. A new method of overcoating TRISO particles with the resinated graphite matrix eliminates the use of hazardous, flammable liquids, produces highly spherical particles with a narrow size distribution, and attains product yields in excess of 99%. Compact fabrication processes have been scaled-up and automated with relatively minor changes to compact quality to manual laboratory-scale processes. The impact on statistical variability of the processes and the products as equipment was scaled are discussed. The prototypic production-scale processes produce test fuels that meet fuel quality specifications.

  3. Characterization and property evaluation of (Th–3.75U)O{sub 2+x} fuel pellets fabricated by impregnated agglomerate pelletization (IAP) process

    Energy Technology Data Exchange (ETDEWEB)

    Baghra, C.; Sathe, D.B.; Prakash, A.; Mishra, A.K.; Afzal, Mohd [Advanced Fuel Fabrication Facility (AFFF), Bhabha Atomic Research Center (BARC), Tarapur Complex 401502, Maharashtra (India); Panakkal, J.P., E-mail: panakkal@barctara.gov.in [Advanced Fuel Fabrication Facility (AFFF), Bhabha Atomic Research Center (BARC), Tarapur Complex 401502, Maharashtra (India); Kamath, H.S. [Advanced Fuel Fabrication Facility (AFFF), Bhabha Atomic Research Center (BARC), Tarapur Complex 401502, Maharashtra (India)

    2013-06-15

    Highlights: ► Characterization of (Th–3.75%U)O{sub 2+x} pellet fabricated by a new technique i.e., impregnated agglomerate pelletization (IAP). ► Comparison with pellets fabricated by powder to pellet (POP) and coated agglomerate pelletization processes. ► Solid solution was more complete in POP and IAP pellets. ► Uranium distribution was less uniform in the pellets fabricated by the CAP route. -- Abstract: Impregnated agglomerate pelletization (IAP) process has been developed by Advanced Fuel Fabrication Facility (AFFF), Tarapur for the fabrication of (Th–3.75U)O{sub 2+x} mixed oxide fuel for Indian advanced heavy water reactors (AHWR). In this process, ThO{sub 2} spheroids were impregnated with uranyl nitrate solution and the resultant mixture was compacted to form green pellets which were sintered in the oxidizing atmosphere to obtain high density (Th–3.75%U)O{sub 2+x} pellets. An attempt has been made in this paper to characterize the pellets fabricated by IAP route. The characterization of the sintered IAP pellets was made by X-ray diffraction, EPMA, alpha autoradiography, chemical analysis, O/M ratio, immersion density and optical microscopy. The characteristics of (Th–U)O{sub 2} pellets fabricated by impregnated agglomerate pelletization (IAP) were also compared with those fabricated by coated agglomerate pelletization (CAP), and conventional powder pellet (POP) processes. In case of pellets fabricated by IAP route, XRD data showed the presence of single fluorite phase. The uranium concentration and grain size distribution were found to be uniform throughout the pellet. These phase characteristics were also found to be more uniform in pellets made by both IAP and POP processes as compared to pellets fabricated using the CAP process.

  4. Characterization and property evaluation of (Th–3.75U)O2+x fuel pellets fabricated by impregnated agglomerate pelletization (IAP) process

    International Nuclear Information System (INIS)

    Baghra, C.; Sathe, D.B.; Prakash, A.; Mishra, A.K.; Afzal, Mohd; Panakkal, J.P.; Kamath, H.S.

    2013-01-01

    Highlights: ► Characterization of (Th–3.75%U)O 2+x pellet fabricated by a new technique i.e., impregnated agglomerate pelletization (IAP). ► Comparison with pellets fabricated by powder to pellet (POP) and coated agglomerate pelletization processes. ► Solid solution was more complete in POP and IAP pellets. ► Uranium distribution was less uniform in the pellets fabricated by the CAP route. -- Abstract: Impregnated agglomerate pelletization (IAP) process has been developed by Advanced Fuel Fabrication Facility (AFFF), Tarapur for the fabrication of (Th–3.75U)O 2+x mixed oxide fuel for Indian advanced heavy water reactors (AHWR). In this process, ThO 2 spheroids were impregnated with uranyl nitrate solution and the resultant mixture was compacted to form green pellets which were sintered in the oxidizing atmosphere to obtain high density (Th–3.75%U)O 2+x pellets. An attempt has been made in this paper to characterize the pellets fabricated by IAP route. The characterization of the sintered IAP pellets was made by X-ray diffraction, EPMA, alpha autoradiography, chemical analysis, O/M ratio, immersion density and optical microscopy. The characteristics of (Th–U)O 2 pellets fabricated by impregnated agglomerate pelletization (IAP) were also compared with those fabricated by coated agglomerate pelletization (CAP), and conventional powder pellet (POP) processes. In case of pellets fabricated by IAP route, XRD data showed the presence of single fluorite phase. The uranium concentration and grain size distribution were found to be uniform throughout the pellet. These phase characteristics were also found to be more uniform in pellets made by both IAP and POP processes as compared to pellets fabricated using the CAP process

  5. Fabrication of 4H-SiC PiN diodes without bipolar degradation by improved device processes

    Science.gov (United States)

    Bu, Yuan; Yoshimoto, Hiroyuki; Watanabe, Naoki; Shima, Akio

    2017-12-01

    We developed a simple technology for fabricating bipolar degradation-free 6.5 kV SiC PiN diodes on the basal plane dislocation (BPD)-free areas of commercially available 4H-SiC wafers. In order to suppress process-induced basal plane dislocation, we first investigated the causes of BPD generation during fabrication and then improved the processes. We found that no BPD was induced on a flat Si-face, but a large number of BPDs were concentrated in the mesa edge after high-dose Al ions were implanted [p++ ion implantation (I. I.)] at room temperature (RT) followed by activation annealing. Therefore, we examined new technologies in device processes including (I) long-term high-temperature oxidation after the mesa process to remove etching damage in the mesa edge and (II) reducing the Al dose (p+ I. I.) in the mesa edge to suppress BPD generation. We investigated the effect of the Al dose in the mesa edge on BPD generation and bipolar degradation. The results indicated that no BPD appeared when the dose was lower than 1 × 1015 atoms/cm2 and when long-term high-temperature oxidation was applied after the mesa process. As a result, we successfully fabricated 6.5 kV PiN diodes without bipolar degradation on BPD-free areas. Moreover, the diodes are very stable when applying 270 A/cm2 for over 100 h. Photoluminescence (PL) observation indicated that no BPD was generated during the improved fabrication processes. Besides, the Ir-Vr measurements showed that the breakdown voltage was over 8 kV at RT. The leakage currents are as low as 7.6 × 10-5 mA/cm2 (25 °C) and 6.3 × 10-4 mA/cm2 (150 °C) at 6.5 kV. Moreover, this result is applicable not only for PiN diodes but also for MOSFETs (body diode), IGBTs, thyristors, etc.

  6. [Effect of fluoride concentration on the corrosion behavior of cobalt-chromium alloy fabricated by two different technology processes].

    Science.gov (United States)

    Qiuxia, Yang; Ying, Yang; Han, Xu; Di, Wu; Ke, Guo

    2016-02-01

    This study aims to determine the effect of fluoride concentration on the corrosion behavior of cobalt-chromium alloy fabricated by two different technology processes in a simulated oral environment. A total of 15 specimens were employed with selective laser melting (SLM) and another 15 for traditional casting (Cast) in cobalt-chromium alloy powders and blocks with the same material composition. The corrosion behavior of the specimens was studied by potentiodynamic polarization test under different oral environments with varying solubilities of fluorine (0, 0.05%, and 0.20% for each) in acid artificial saliva (pH = 5.0). The specimens were soaked in fluorine for 24 h, and the surface microstructure was observed under a field emission scanning electron microscope after immersing the specimens in the test solution at constant temperature. The corrosion potential (Ecorr) value of the cobalt-chromium alloy cast decreased with increasing fluoride concentration in acidic artificial saliva. The Ecorr, Icorr, and Rp values of the cobalt-chromium alloy fabricated by two different technology processes changed significantly when the fluoride concentration was 0.20% (P technology processes exhibited a statistically significant difference. The Icorr value of the cobalt-chromium alloy cast was higher than that in the SLM group cobalt-chromium alloy when the fluoride concentration was 0.20% (P technology processes. The corrosion resistance of the cobalt-chromium alloy cast was worse than that of the SLM group cobalt-chromium alloy when the fluoride concentration was 0.20%.

  7. Simple Fabrication Process for 2D ZnO Nanowalls and Their Potential Application as a Methane Sensor

    Directory of Open Access Journals (Sweden)

    Zhan-Shuo Hu

    2013-03-01

    Full Text Available Two-dimensional (2D ZnO nanowalls were prepared on a glass substrate by a low-temperature thermal evaporation method, in which the fabrication process did not use a metal catalyst or the pre-deposition of a ZnO seed layer on the substrate. The nanowalls were characterized for their surface morphology, and the structural and optical properties were investigated using scanning electron microscopy (SEM, X-ray diffraction (XRD, transmission electron microscopy (TEM, and photoluminescence (PL. The fabricated ZnO nanowalls have many advantages, such as low growth temperature and good crystal quality, while being fast, low cost, and easy to fabricate. Methane sensor measurements of the ZnO nanowalls show a high sensitivity to methane gas, and rapid response and recovery times. These unique characteristics are attributed to the high surface-to-volume ratio of the ZnO nanowalls. Thus, the ZnO nanowall methane sensor is a potential gas sensor candidate owing to its good performance.

  8. Design and optimization of the production process of radiopharmaceutical {sup 177}Lu-DOTA-Nal{sup 3}-Octreotide for the treatment of gastro-entero-pancreatic tumors; Diseno y optimizacion del proceso de produccion del radiofarmaco {sup 177}Lu-DOTA-Nal{sup 3}-Octreotido para el tratamiento de tumores gastroenteropancreaticos

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez G, M. F.

    2013-07-01

    The radiolabel peptides are molecules of interest in nuclear medicine for their therapeutic and diagnostic application in cancer. Among an impressing group of relevant peptides, those similar of the somatostatin, as the Nal{sup 3}-Octreotide (NOC), have established as potential radiopharmaceuticals when presenting significant affinity for the receptors of this peptide hormone that are over expressed and broadly distributed in tumors of neuroendocrine origin, as the gastro-entero-pancreatic tumors. On the other hand, the Lutetium-177 ({sup 177}Lu) is an ideal candidate for the peptides radiolabel and has favorable characteristics to be used in radionuclide therapy. The objective of this work was designing, optimizing and to document the production process of the radiopharmaceutical {sup 177}Lu-DOTA-Nal{sup 3}-Octreotide ({sup 177}Lu-DOTANOC) for the solicitude of its sanitary registration before the Comision Federal contra Riesgos Sanitarios (COFEPRIS). For the optimization of the production process a factorial design of three variables was evaluated with mixed levels (18 combinations), where the dependent variable is the radiochemical purity and the analytic method used to determine this parameter (High Performance Liquid Chromatography) was validated. Later on, by means of the production of 3 lots of the optimized formula of the radiopharmaceutical {sup 177}Lu-DOTANOC the production process was validated and the stability long term study to determine the period of useful life was carried out. The following pharmaceutical formulation was adopted as good: 1.85 GBq (0.5μg) of {sup 177}Lu, 250 μg of DOTANOC and 150 μL of acetates Buffer 1 M ph 5 in 5 m L of the medium. The analytic method used to determine the radiochemical purity of the formulation satisfied the requirements for the wished analytic application. We can conclude that the 3 validation lots prepared under protocols of Good Production Practices, in the Plant of Radiopharmaceuticals Production of the

  9. Evaluation on microscopic damage and fabrication process of shape memory alloy

    International Nuclear Information System (INIS)

    Lee, Jin Kyung; Choi, Il Kook; Park, Young Chul; Lee, Kyu Chang; Lee, Jun Hyun

    2002-01-01

    Shape memory alloy has been used to improve the tensile strength of composite by the occurrence of compressive residual stress in matrix using its shape memory effect. In order to fabricate shape memory alloy composite, TiNi alloy and Al6061 were used as reinforcing material and matrix, respectively. In this study, TiNi/Al6061 shape memory alloy composite was made by using hot press method. However, the specimen fabricated by this method had the bonding problem at tile boundary between TiNi fiber anti Al matrix when the load was applied to it. A cold rolling was imposed to the specimen to improve the bonding effort. It was found that tensile strength of specimen subjected to cold rolling was more increased than that of specimen which did not underwent cold rolling. In addition, acoustic emission technique was used to quantify the microscopic damage behavior of cold rolled TiNi/Al6061 shape memory alloy composite at high temperature.

  10. Self-fabrication of void array in fused silica by femtosecond laser processing

    International Nuclear Information System (INIS)

    Toratani, Eiji; Kamata, Masanao; Obara, Minoru

    2005-01-01

    We demonstrate self-fabrication of a submicrometer-sized void array in fused silica using a 100 fs 0.2-3 μJ Ti:Sapphire femtosecond laser and a high 0.9 numerical aperture (NA) objective lens. The effect of the focusing conditions of NA, laser energy, and pulse number on the shape of the fabricated void was investigated. The void has a linearly drawn shape in the direction of the laser irradiation when a single pulse is irradiated and an increasing number of incident pulses resulted in the break up of the long void into multiple spherical ones, leading to a periodically aligned void array. The void shape also varied with the depth of the focus point beneath the fused silica surface, because the amount of self-focusing has a significant effect on the generation of the voids. The void shape was narrower and longer when the laser pulse was focused with the higher NA (up to 0.9) objective lens in the deeper position (up to 70 μm) in the fused silica

  11. Fabrication of superhydrophobic polymethylsilsesquioxane nanostructures on cotton textiles by a solution-immersion process.

    Science.gov (United States)

    Shirgholami, Mohammad A; Khalil-Abad, Mohammad Shateri; Khajavi, Ramin; Yazdanshenas, Mohammad E

    2011-07-15

    Superhydrophobic cotton textiles are prepared by a simple, one-step and inexpensive phase separation method under ambient conditions by which a layer of polymethylsilsesquioxane (PMSQ) nanostructures is covered onto the cellulose fibers. By changing the silane precursor concentration, PMSQ nanostructures with various shapes, morphologies and sizes were fabricated. Nanostructures were characterized using SEM, EDS, and attenuated total reflectance FTIR. The wettability of the modified cellulose surfaces was characterized with contact-angle goniometry and sliding angle technique, respectively. The water contact angle of modified cotton is measured to be higher than 150°, which is high enough to exhibit the lotus effect as a result of the superhydrophobicity. Tunable water-repellent properties of the fabric are also demonstrated, with sliding contact angles varying from "sticky" to "slippery" depending upon different nanostructures on the surface of the fibers. It is expected that this simple technique will accelerate the large-scale production of superhydrophobic cellulosic materials with new industrial applications. Copyright © 2011 Elsevier Inc. All rights reserved.

  12. Design and simulation of an automation system of a production process and fractionation of {sup 131}I, using strategies of advanced control; Diseno y simulacion de un sistema de automatizacion del proceso de produccion y fraccionamiento de {sup 131}I, utilizando estrategias de control avanzado

    Energy Technology Data Exchange (ETDEWEB)

    Paez, Jose; Arias, Pablo; Miranda, Jesus, E-mail: jpaez@jpen.gob.pe, E-mail: parias@ipen.gob.pe, E-mail: jmiranda@ipen.gob.pe [Instituto Peruano de Energia Nuclear (lPEN), Lima (Peru). Direccion de Servicios. Division de Instrumentacion Nuclear

    2013-10-01

    In this report, the results are obtained in the design and simulation of a control system using advanced strategies in a production cell in the Plant Production of Radioisotopes of IPEN. The results demonstrate that the temperature of the coalition oven is stabilized after 30 minutes, being constituted in an advantage to obtain the maximum yield of the cell production of {sup 131}I; also, an integral good controller has been designed that allows to obtain a mathematical model that reproduces with enough accuracy the behavior of the process. With the final simulation it has been to demonstrate that the System Control of Temperature of the Cell Production of {sup 131}I is a controllable system and allows to carry out the respective sequence with other variables of control of the production cell. (author)

  13. Instrumental set up for the study of water erosion processes to different scales in the upper Barranc de Carraixet water basin; Diseno instrumental para el estudio de los procesos de erosion hidrica a distintas escalas en la cuenca alta del Barranc del Carraixet

    Energy Technology Data Exchange (ETDEWEB)

    Rubio, J. L.; Pascual-Aguilar, J. A.; Andreu, V.

    2009-07-01

    As a result of the rainfall conversion into overland flow, two major fluxes are established, the water flow and the associated erosion flow. The process complexity and heterogeneity together with the numerous factor that interact recommend the use of multi-scale approaches for a better understanding. Thus the methodological approach established in this work focus on a hierarchical instrumental implementation at different spatial scales within the same watershed, the Barranc the Carraixet Head Waters, in the vicinity of the city of Valencia, spain. For the instrumentation setting up, four data gathering structures have been designed, from the micro plot scale to the medium size drainage basin of several square kilometres. (Author) 5 refs.

  14. Biological implications of lab-on-a-chip devices fabricated using multi-jet modelling and stereolithography processes

    Science.gov (United States)

    Zhu, Feng; Macdonald, Niall; Skommer, Joanna; Wlodkowic, Donald

    2015-06-01

    Current microfabrication methods are often restricted to two-dimensional (2D) or two and a half dimensional (2.5D) structures. Those fabrication issues can be potentially addressed by emerging additive manufacturing technologies. Despite rapid growth of additive manufacturing technologies in tissue engineering, microfluidics has seen relatively little developments with regards to adopting 3D printing for rapid fabrication of complex chip-based devices. This has been due to two major factors: lack of sufficient resolution of current rapid-prototyping methods (usually >100 μm ) and optical transparency of polymers to allow in vitro imaging of specimens. We postulate that adopting innovative fabrication processes can provide effective solutions for prototyping and manufacturing of chip-based devices with high-aspect ratios (i.e. above ration of 20:1). This work provides a comprehensive investigation of commercially available additive manufacturing technologies as an alternative for rapid prototyping of complex monolithic Lab-on-a-Chip devices for biological applications. We explored both multi-jet modelling (MJM) and several stereolithography (SLA) processes with five different 3D printing resins. Compared with other rapid prototyping technologies such as PDMS soft lithography and infrared laser micromachining, we demonstrated that selected SLA technologies had superior resolution and feature quality. We also for the first time optimised the post-processing protocols and demonstrated polymer features under scanning electronic microscope (SEM). Finally we demonstrate that selected SLA polymers have optical properties enabling high-resolution biological imaging. A caution should be, however, exercised as more work is needed to develop fully bio-compatible and non-toxic polymer chemistries.

  15. FABRIC QUALITY CONTROL SYSTEMS

    Directory of Open Access Journals (Sweden)

    Özlem KISAOĞLU

    2006-02-01

    Full Text Available Woven fabric quality depends on yarn properties at first, then weaving preparation and weaving processes. Defect control of grey and finished fabric is done manually on the lighted tables or automatically. Fabrics can be controlled by the help of the image analysis method. In image system the image of fabrics can be digitized by video camera and after storing controlled by the various processing. Recently neural networks, fuzzy logic, best wavelet packet model on automatic fabric inspection are developed. In this study the advantages and disadvantages of manual and automatic, on-line fabric inspection systems are given comparatively.

  16. One step phase separation process to fabricate superhydrophobic PVC films and its corrosion prevention for AZ91D magnesium alloy

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Na; Li, Jicheng; Bai, Ningning; Xu, Lan; Li, Qing, E-mail: liqingswu@163.com

    2016-07-15

    Graphical abstract: - Highlights: • Independent superhydrophobic polyvinyl chloride (PVC) film was prepared by phase separation process. • The superhydrophobic PVC film showed excellent stability in acid, alkali and salt corrosive solutions. • This film was prepared on magnesium surface protecting it from corrosion. • This method was simple and universal. - Abstract: A one step, simple fabrication method to prepare independent superhydrophobic polyvinyl chloride (PVC) coating is reported in this paper. The rough surface structure and low surface energy could be simply obtained only by a phase separation process. The independent PVC superhydrophobic film was also applied on AZ91D magnesium alloy. Scanning electron microscopy (SEM), water contact angle measurements, electrochemical test and adhesion tests have been performed to characterize the surface morphology, wettability, anti-corrosion and adhesion strength of independent PVC film and superhydrophobic magnesium alloy respectively. The results indicated that whether it was the PVC film or superhydrophobic magnesium, they show static contact angles higher than 150°, excellent anti-corrosion effect and adhesion strength. We believed that the presented method could provide a straightforward and simple route to fabricate low-cost and anti-corrosion coating on various substrate materials. Moreover, this one step process may find potential application in the field of industry because of its simplicity and universality.

  17. Hybrid fabrication process of additive manufacturing and direct writing for a 4 X 4 mm matrix flexible tactile sensor

    Energy Technology Data Exchange (ETDEWEB)

    Woo, Sang Gu; Lee, In Hwan [Chungbuk National University, Chungju (Korea, Republic of); Lee, Kyong Chang [Pukyong National University, Busan (Korea, Republic of)

    2015-09-15

    Various machines require data from their external environments for safety and/or accuracy. In this respect, many sensors that mimic the human sensory system have been investigated. Among these, tactile sensors may be useful for obtaining data on the roughness of, and external forces acting upon, an object. Several tactile sensors have been developed; however, these are typically fabricated via a series of complex processes, and hence are unsuitable for volume manufacturing. In this paper, we report a fabrication process for a 4 X 4 mm matrix flexible sensor element using layered manufacturing and direct-write technology. A composite composed of photocurable resin and Multi-walled carbon nanotubes (MWCNTs) was used as the sensing material. The MWCNTs were mixed with the photocurable resin using ultrasonic dispersion, and the liquid mixture exhibited excellent piezoresistive properties following curing using ultraviolet light. The used photocurable resin is flexible and elastic after curing. Therefore, the composite material can be bent and deformed. To use this composite material with the flexible sensor, dispensing characteristics were examined using direct-write technology. For the acquisition of sensor data, a commercial pin-header was inserted and photocurable resin was filled up to the height of pin-header and cured . Then, the composite material was dispensed onto the pin-header as a sensing material. Using this process, a flexible sensor with piezoresistive properties was formed.

  18. Considerations on a sol-gel type process as a fuel fabrication route for the actinide recycle

    International Nuclear Information System (INIS)

    Facchini, A.G.; Gallone, S.; Zamorani, E.

    1980-01-01

    The technology based on the powder pelletizing faces relevant difficulties, when used to fabricate both targets and fuels containing transplutonium elements. The applicability of the Gel-Supported Precipitation process (GSP) as an alternative, has been examined on the ground of the know-how gained in producing U-Pu mixed oxide microspheres or granules suitable for pressing. The applicability of the process has been examined on the basis of the following factors: - the properties of the actinide solutions obtained through the HAW partitioning; - the target and fuel element composition and geometry which must be met in order to perform a homogeneous or a heterogeneous recycle in the FBR's and in the LWR's; - the actinide radiolytical effects on the compounds used to produce either microspheres or granules; - the criticality aspects. This paper shall be considered as a first attempt only; how ever, it can be useful in evaluating the different alternatives from the GSP fabrication standpoint. Moreover, some areas for further experimental research are indicated to confirm the applicability of the GSP process

  19. Sub wavelength Microstructures Fabrication by Self-Organization Processes in Photopolymerizable Nano composite

    International Nuclear Information System (INIS)

    Denisyuk, I.Yu.; Sobeshuk, N.O.; Burunkova, J.A.; Vorzobova, N.D.

    2012-01-01

    This paper describes our research results on nanometers sizes sub wavelength nano structure fabrication by UV curing of special nano composite material with self-organization and light self-focusing effects. For this purpose, special UV curable nano composite material with a set of effects was developing: light self-focusing in the photo polymer with positive refractive index change, self-organization based on photo-induced nanoparticles transportation, and oxygen-based polymerization threshold. Both holographic and projection lithography writing methods application for microstructure making shows geometrical optical laws perturbation as result of nano composite self-organization effects with formation of nanometers-sized high-aspect-ratio structures. Obtained results will be useful for diffraction limit overcoming in projection lithography as well as for deep lithography technique.

  20. Hydrophobic and hydrophilic surface nano-modification of PET fabric by plasma process.

    Science.gov (United States)

    Paosawatyanyong, B; Kamlangkla, K; Hodak, S K

    2010-11-01

    Polyethylene terephthalate (PET) fabrics were treated by radio frequency inductively coupled plasma (RF-ICP) to modify their hydrophobic and hydrophilic properties. Types of gases which were SF6, O2, N2 and Ar, treatment time, pressure and RF power were varied systematically. The water droplet contact angle measurements showed that, treating with SF6 plasma would result in the increase of hydrophobicity of PET samples while treating with O2, N2 and Ar plasmas would yield hydrophilic properties. In both hydrophobic and hydrophilic cases, the surface morphology of PET fibers was roughened after exposed to plasma. Hence, it is not obvious that these surface roughness induced by plasma is sufficient to yield the increase in hydrophobicity by the well known lotus effect.

  1. Process for fabricating polycrystalline semiconductor thin-film solar cells, and cells produced thereby

    Science.gov (United States)

    Wu, Xuanzhi; Sheldon, Peter

    2000-01-01

    A novel, simplified method for fabricating a thin-film semiconductor heterojunction photovoltaic device includes initial steps of depositing a layer of cadmium stannate and a layer of zinc stannate on a transparent substrate, both by radio frequency sputtering at ambient temperature, followed by the depositing of dissimilar layers of semiconductors such as cadmium sulfide and cadmium telluride, and heat treatment to convert the cadmium stannate to a substantially single-phase material of a spinel crystal structure. Preferably, the cadmium sulfide layer is also deposited by radio frequency sputtering at ambient temperature, and the cadmium telluride layer is deposited by close space sublimation at an elevated temperature effective to convert the amorphous cadmium stannate to the polycrystalline cadmium stannate with single-phase spinel structure.

  2. Effects of thermal budget in n-type bifacial solar cell fabrication processes on effective lifetime of crystalline silicon

    Directory of Open Access Journals (Sweden)

    Tomihisa Tachibana

    2017-04-01

    Full Text Available The effects of residual C on cell properties are investigated from the view point of thermal budget in the n-type bifacial cell processes. Implied Voc obtained from wafers with same Oi concentration depend on the thermal budgets decreases as the Cs concentration increases. The Voc values vary depending on the wafer with different growth cooling rate. To analyze the effect of thermal budget correspond to solar cell fabrication process, CZ wafers with almost the same Oi concentrations are prepared. One of the wafers with relatively high residual Cs concentration shows the longer lifetime than the initial value after the 950 oC annealing step. On the other hand, the lifetime of a wafer with relatively low Cs concentration dramatically decreased by the same process due to the O segregation. These results suggest that it is important to choose appropriate wafer specification, starting with feedstock material, for increasing the solar cell efficiency.

  3. Microstructure of Semi-Solid 6063 Alloy Fabricated by Radial Forging Combined with Unidirectional Compression Recrystallization and Partial Melting Process

    Directory of Open Access Journals (Sweden)

    Wang Yongfei

    2017-01-01

    Full Text Available Radial forging combined with unidirectional compression (RFCUM is introduced in recrystallization and partial melting (RAP to fabricate semi-solid 6063 aluminum alloy, which can be defined as a process of RFCUM-RAP. In this study, the microstructures of semi-solid 6063 alloy prepared by semi-solid isothermal treatment (SSIT and RFCUM-RAP processes are investigated. The results show that, the solid grains of semi-solid alloy prepared by SSIT are large and irregular. However, solid grains of semi-solid billet prepared by RFCUC-RAP are fine and spherical. Additionally, during RFCUC-RAP process, with the increase of isothermal holding time, the shape of solid grain is more and more spherical, but the size of solid grain is gradually increased. To obtain ideal semi-solid microstructure, the optimal isothermal holding temperature and time are 630 °C and 5~10 min, respectively.

  4. PLC and SCADA based automation of injection casting process for casting of uranium-zirconium blanket fuel slugs for metallic fuel fabrication

    International Nuclear Information System (INIS)

    Yathish Kumar, G.; Jagadeeschandran, J.; Avvaru, Prafulla Kumar; Yadaw, Abhishek Kumar; Lavakumar, R.; Prabhu, T.V.; Muralidharan, P.; Anthonysamy, S.

    2016-01-01

    Fabrication of metallic (U-6wt.%Zr) slugs involves melting of binary alloy under vacuum and injection casting into quartz moulds at high pressure. Injection casting system housed inside glove box comprises of high vacuum, induction melting, high pressure control, motion control, mould preheating, chamber cooling, crucible handling and glove box pressure control systems. The technology development for process automation of injection casting system and process optimisation for fabrication of metallic (U-6%Zr) slugs is outlined in this paper. (author)

  5. Tech-X Corporation releases simulation code for solving complex problems in plasma physics : VORPAL code provides a robust environment for simulating plasma processes in high-energy physics, IC fabrications and material processing applications

    CERN Multimedia

    2005-01-01

    Tech-X Corporation releases simulation code for solving complex problems in plasma physics : VORPAL code provides a robust environment for simulating plasma processes in high-energy physics, IC fabrications and material processing applications

  6. Development of fabrication process of upper nozzle BIBLIS type of PWR fuel element

    International Nuclear Information System (INIS)

    Miranda, O.; Lorenzo, D.F.R.

    1982-01-01

    Process and parameters of milling and welding of a upper nozzle BIBLIS type prototype are presented. Milling process, cutting tools studies, production devices and inspection were developed and researched. (author) [pt

  7. Water-soluble cellulose acetate from waste cotton fabrics and the aqueous processing of all-cellulose composites.

    Science.gov (United States)

    Cao, Jie; Sun, Xunwen; Lu, Canhui; Zhou, Zehang; Zhang, Xinxing; Yuan, Guiping

    2016-09-20

    The objective of this study is to explore the possibility of using waste cotton fabrics (WCFs) as low cost feedstock for the production of value-added products. Our previous study (Tian et al., 2014) demonstrated that acidic ionic liquids (ILs) can be highly efficient catalysts for controllable synthesis of cellulose acetate (CA) due to their dual function of swelling and catalyzing. In this study, an optimized "quasi-homogeneous" process which required a small amount of acidic ILs as catalyst was developed to synthesize water-soluble CA from WCFs. The process was optimized by varying the amounts of ILs and the reaction time. The highest conversion of water-soluble CA from WCFs reached 90.8%. The structure of the obtained water-soluble CA was characterized and compared with the original WCFs. Moreover, we demonstrate for the first time that fully bio-based and transparent all-cellulose composites can be fabricated by simple aqueous blending of the obtained water-soluble CA and two kinds of nanocelluloses (cellulose nanocrystals and cellulose nanofibrils), which is attractive for the applications in disposable packaging materials, sheet coating and binders, etc. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Fabrication and Characterization of Porous MgAl2O4 Ceramics via a Novel Aqueous Gel-Casting Process

    Directory of Open Access Journals (Sweden)

    Lei Yuan

    2017-11-01

    Full Text Available A novel and aqueous gel-casting process has been successfully developed to fabricate porous MgAl2O4 ceramics by using hydratable alumina and MgO powders as raw materials and deionized water as hydration agent. The effects of different amounts of deionized water on the hydration properties, apparent porosity, bulk density, microstructure, pore size distribution and compressive strength of the samples were investigated. The results indicated that the porosity and the microstructure of porous MgAl2O4 ceramics were governed by the amounts of deionized water added. The porous structure was formed by the liberation of physisorbed water and the decomposition of hydration products such as bayerite, brucite and boehmite. After determining the addition amounts of deionized water, the fabricated porous MgAl2O4 ceramics had a high apparent porosity (52.5–65.8%, a small average pore size structure (around 1–3 μm and a relatively high compressive strength (12–28 MPa. The novel aqueous gel-casting process with easy access is expected to be a promising candidate for the preparation of Al2O3-based porous ceramics.

  9. Understanding the Thermal Properties of Precursor-Ionomers to Optimize Fabrication Processes for Ionic Polymer-Metal Composites (IPMCs

    Directory of Open Access Journals (Sweden)

    Sarah Trabia

    2018-04-01

    Full Text Available Ionic polymer-metal composites (IPMCs are one of many smart materials and have ionomer bases with a noble metal plated on the surface. The ionomer is usually Nafion, but recently Aquivion has been shown to be a promising alternative. Ionomers are available in the form of precursor pellets. This is an un-activated form that is able to melt, unlike the activated form. However, there is little study on the thermal characteristics of these precursor ionomers. This lack of knowledge causes issues when trying to fabricate ionomer shapes using methods such as extrusion, hot-pressing, and more recently, injection molding and 3D printing. To understand the two precursor-ionomers, a set of tests were conducted to measure the thermal degradation temperature, viscosity, melting temperature, and glass transition. The results have shown that the precursor Aquivion has a higher melting temperature (240 °C than precursor Nafion (200 °C and a larger glass transition range (32–65°C compared with 21–45 °C. The two have the same thermal degradation temperature (~400 °C. Precursor Aquivion is more viscous than precursor Nafion as temperature increases. Based on the results gathered, it seems that the precursor Aquivion is more stable as temperature increases, facilitating the manufacturing processes. This paper presents the data collected to assist researchers in thermal-based fabrication processes.

  10. Rack-Scale Storage Fabric: A Practical Way to Build Best-Fit Infrastructure for High-Performance Data Processing

    Directory of Open Access Journals (Sweden)

    Ding Ruiquan

    2016-01-01

    Full Text Available This paper is to address the resource utilization problem for high-performance data processing applications in a large IDC (Internet Data Center environment. On one hand, each application calls for a best-fit infrastructure with a specific compute-storage ratio, to achieve the highest resource utilization while meeting its performance requirement. And such a ratio varies among applications. On the other hand, IDCs have always been trying to unify the infrastructures for lower TCO (Total Cost of Ownership. Therefore, it’s getting harder and harder to adapt infrastructures to application needs. This issue results in significant waste of investment in large IDCs. Furthermore, the high-performance data processing applications always require the infrastructure to offer as high compute-storage performance as a DAS (Direct Attached Storage server, which remains as a great challenge when addressing the resource utilization problem. This paper, as part of Baidu-Intel joint research program, first evaluates the state-of-the-art solutions, and then introduces a more practical infrastructure, the core of which is rack-scale storage fabric. This infrastructure disaggregates compute units and storage units by a SAS (Serial Attached SCSI fabric, and allows to compose logical servers with arbitrary computer-storage ratios within a rack. And the experiments in Baidu’s research environment show that the logical servers exhibit the similar throughput/IOPS as DAS servers, and also their compute-storage ratios can best-fit the needs of different Hadoop applications.

  11. Hot Isostatic Press Manufacturing Process Development for Fabrication of RERTR Monolithic Fuel Plates

    Energy Technology Data Exchange (ETDEWEB)

    Crapps, Justin M. [Los Alamos National Laboratory; Clarke, Kester D. [Los Alamos National Laboratory; Katz, Joel D. [Los Alamos National Laboratory; Alexander, David J. [Los Alamos National Laboratory; Aikin, Beverly [Los Alamos National Laboratory; Vargas, Victor D. [Los Alamos National Laboratory; Montalvo, Joel D. [Los Alamos National Laboratory; Dombrowski, David E. [Los Alamos National Laboratory; Mihaila, Bogdan [Los Alamos National Laboratory

    2012-06-06

    We use experimentation and finite element modeling to study a Hot Isostatic Press (HIP) manufacturing process for U-10Mo Monolithic Fuel Plates. Finite element simulations are used to identify the material properties affecting the process and improve the process geometry. Accounting for the high temperature material properties and plasticity is important to obtain qualitative agreement between model and experimental results. The model allows us to improve the process geometry and provide guidance on selection of material and finish conditions for the process strongbacks. We conclude that the HIP can must be fully filled to provide uniform normal stress across the bonding interface.

  12. Proposed method for the hydraulic design of ski-jump energy dissipators in dam spillways considering the occurrence of scour holes downstream of the structure; Metodo propuesto para el diseno hidraulico de trampolines empleados como disipadores de energia en aliviaderos para presas, considerando la ocurrencia del cono de socavacion al pie del mismo

    Energy Technology Data Exchange (ETDEWEB)

    Pardo-Gomez, Rafael [Centro de Investigaciones Hidraulicas (Cuba)

    2008-04-15

    Ski-jump energy dissipators are widely used in hydraulic engineering because of their well-known effectiveness. Nevertheless, some uncertainty exits associated with the dimensions of the scour hole appearing downstream of the structure. This paper presents a new method for solving this problem. This method includes spillway stability checking as part of the design process and also stability checking of any other construction near the energy dissipation zone. [Spanish] Los disipadores de energia tipo trampolin tienen amplia utilizacion en la practica de la ingenieria hidraulica por su probada eficacia; sin embargo, su diseno esta sujeto a cierto grado de incertidumbre en cuanto a la prediccion de las dimensiones del cono de socavacion que habra de producirse aguas abajo de la estructura. En el presente trabajo se muestra un metodo novedoso, mediante el cual el autor soluciona el aspecto antes referido, toda vez que se incluye como parte del proceso de diseno la comprobacion de la estabilidad del propio aliviadero o de cualquier otra obra cercana a la zona de disipacion de energia.

  13. Luminescent antireflective coatings with disordered surface nanostructures fabricated by liquid processes.

    Science.gov (United States)

    Tanaka, Sota; Fujihara, Shinobu

    2011-03-15

    Antireflective phosphor coatings having disordered surface nanostructures were fabricated by a sol-gel dip coating method and a subsequent hot water treatment. Thin films of a Bi(3+),Eu(3+)-codoped YVO4 red phosphor were first prepared and effects of the addition of an aluminum source to precursor solutions on their microstructure and optical properties were examined. Optical transmittance of the YVO4:Bi(3+),Eu(3+) film was lower than that of a bare quartz glass substrate due to a higher refractive index of YVO4. The addition of the aluminum source and the hot water treatment resulted in a considerable increase of transmittance and its smaller angular dependence, which could generate an antireflective effect by the phosphor thin films. Observation of the microstructure revealed that the hot water treatment brought a remarkable change in the surface as well as the cross-section structure in the aluminum-added YVO4:Bi(3+),Eu(3+) film. The film density and hence the refractive index were gradually changed like a pseudo moth-eye structure, which explained the occurrence of the antireflective effect. The microstructural change was attributed to the dissolution of alumina present in the film and the reprecipitation of boehmite on the film surface during the hot water treatment. Photoluminescence of the YVO4:Bi(3+),Eu(3+) film could also be enhanced by the antireflective effect due to the suppression of surface Fresnel reflection of incident light and total internal reflection of emitted light.

  14. Efficient OLEDs Fabricated by Solution Process Based on Carbazole and Thienopyrrolediones Derivatives

    Directory of Open Access Journals (Sweden)

    Luis-Abraham Lozano-Hernández

    2018-01-01

    Full Text Available Four low molecular weight compounds—three of them new, two of them with carbazole (Cz as functional group and the other two with thienopyrroledione (TPD group—were used as emitting materials in organic light emitting diodes (OLEDs. Devices were fabricated with the configuration ITO/PEDOT:PSS/emitting material/LiF/Al. The hole injector layer (HIL and the emitting sheet were deposited by spin coating; LiF and Al were thermally evaporated. OLEDs based on carbazole derivatives show luminances up to 4130 cd/m2, large current efficiencies about 20 cd/A and, cautiously, a very impressive External Quantum Efficiency (EQE up to 9.5%, with electroluminescence peaks located around 490 nm (greenish blue region. Whereas, devices manufactured with TPD derivatives, present luminance up to 1729 cd/m2, current efficiencies about 4.5 cd/A and EQE of 1.5%. These results are very competitive regarding previous reported materials/devices.

  15. One-step electrodeposition process to fabricate corrosion-resistant superhydrophobic surface on magnesium alloy.

    Science.gov (United States)

    Liu, Qin; Chen, Dexin; Kang, Zhixin

    2015-01-28

    A simple, one-step method has been developed to construct a superhydrophobic surface by electrodepositing Mg-Mn-Ce magnesium plate in an ethanol solution containing cerium nitrate hexahydrate and myristic acid. Scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, and Fourier transform infrared spectroscopy were employed to characterize the surfaces. The shortest electrodeposition time to obtain a superhydrophobic surface was about 1 min, and the as-prepared superhydrophobic surfaces had a maximum contact angle of 159.8° and a sliding angle of less than 2°. Potentiodynamic polarization and electrochemical impedance spectroscopy measurements demonstrated that the superhydrophobic surface greatly improved the corrosion properties of magnesium alloy in 3.5 wt % aqueous solutions of NaCl, Na2SO4, NaClO3, and NaNO3. Besides, the chemical stability and mechanical durability of the as-prepared superhydrophobic surface were also examined. The presented method is rapid, low-cost, and environmentally friendly and thus should be of significant value for the industrial fabrication of anticorrosive superhydrophobic surfaces and should have a promising future in expanding the applications of magnesium alloys.

  16. Fabrication of 3D fine scale PZT components by ink-jet prototyping process

    Science.gov (United States)

    Noguera, R.; Dossou-Yovo, C.; Lejeune, M.; Chartier, T.

    2005-09-01

    Different investigations have been carried out to optimize an ink-jet printing technique, devoted to the fabrication of 3D fine scale PZT parts, by adjustment of the fluid properties of the ceramic suspensions and by controlling the ejection and impact phenomena. A 10 vol% PZT loaded suspension characterized by a Newtonian behavior, corresponding to a viscosity of 10mPa.s and to a ratio Re/We1/2 of 5.98 has been selected. The ejection and impact phenomena strongly depend on the driving parameters of the printing head, in particular the formation of the droplet, with satellite or not, as well as its velocity and volume which are function of the pulse amplitude. Moreover, the conditions of ejection (droplet velocity and volume) control the characteristics of the deposit (definition, spreading, thickness uniformity). Sintered PZT pillar array has been achieved by ink-jet printing with a definition equal to 50μm. These structures could be very useful to improve the performances of 1-3 ceramic polymer composites for imaging probes or more generally for ultrasonic transducers and also of micro-deformable mirrors for optical adaptive systems.

  17. Processing conditions in pulsed laser ablation of gold in liquid for fabrication of nanowire networks

    Energy Technology Data Exchange (ETDEWEB)

    Nikolov, A.S., E-mail: anastas_nikolov@abv.bg [Institute of Electronics, Bulgarian Academy of Sciences, Tsarigradsko Chaussee 72, Sofia 1784 (Bulgaria); Nedyalkov, N.N.; Nikov, R.G.; Dimitrov, I.G.; Atanasov, P.A. [Institute of Electronics, Bulgarian Academy of Sciences, Tsarigradsko Chaussee 72, Sofia 1784 (Bulgaria); Maximova, K.; Delaporte, Ph.; Kabashin, A. [Aix-Marseille University, CNRS, LP3 Laboratory, Marseille 13288 (France); Alexandrov, M.T. [Institute of Experimental Pathology and Parasitology, Bulgarian Academy of Sciences, G. Bonchev Street, bl. 25, Sofia 1113 (Bulgaria); Karashanova, D.B. [Institute of Optical Materials and Technologies, Bulgarian Academy of Sciences, G. Bonchev Street, bl. 109, Sofia 1113 (Bulgaria)

    2014-05-01

    The experimental conditions were investigated enabling one to fabricate Au nanowire networks by pulsed laser ablation in water. The study revealed that it is possible to produce alternatively nanoparticles (or aggregates) or nanowire networks at certain wavelengths depending on the laser fluence. An Au disc immersed in double-distilled water was used as a target. The second (λ{sub SHG} = 532 nm) and the third (λ{sub THG} = 355 nm) harmonics of a Nd:YAG laser system were utilized to produce different Au colloids. The values of the laser fluence for both wavelengths under the experimental conditions chosen were varied from several J/cm{sup 2} to tens of J/cm{sup 2}. The optical extinction spectra of the colloids in the UV/vis region were obtained to evaluate the structure of the dispersed Au phase. Transmission electron microscopy (TEM) was applied to visualize the size and morphology of the colloidal particles. Their structure and phase composition were studied by high-resolution transmission electron microscopy (HRTEM) and selected area electron diffraction (SAED) and used to make an assumption on how they had been formed.

  18. Fabrication of a metallic roll stamp with low internal stress and high hardness for large area display applications by a pulse reverse current electroforming process

    International Nuclear Information System (INIS)

    Kim, Joongeok; Han, Jungjin; Kim, Taekyung; Kang, Shinill

    2014-01-01

    With the increasing demand for large scale micro/nano components in the fields of display, energy and electrical devices, etc, the establishment of a roll imprinting process has become a priority. The fabrication of a roll stamp with high dimensional accuracy and uniformity is one of the key issues in the roll imprinting process, because the roll stamp determines the properties of the replicated micro/nano structures. In this study, a method to fabricate a metallic roll stamp with low internal stress, high flatness, and high hardness was proposed by a pulse reverse current (PRC) electroforming process. The effects of PRC electroforming processes on the internal stress, hardness, and grain size of the electroformed stamp were examined, and the optimum process conditions were suggested. As a practical example of the proposed method, various micro-patterns for electronic circuits were fabricated via the roll imprinting process using a PRC electroformed stamp. (paper)

  19. An Acetone Microsensor with a Ring Oscillator Circuit Fabricated Using the Commercial 0.18 μm CMOS Process

    Directory of Open Access Journals (Sweden)

    Ming-Zhi Yang

    2014-07-01

    Full Text Available This study investigates the fabrication and characterization of an acetone microsensor with a ring oscillator circuit using the commercial 0.18 μm complementary metal oxide semiconductor (CMOS process. The acetone microsensor contains a sensitive material, interdigitated electrodes and a polysilicon heater. The sensitive material is α-Fe2O3 synthesized by the hydrothermal method. The sensor requires a post-process to remove the sacrificial oxide layer between the interdigitated electrodes and to coat the α-Fe2O3 on the electrodes. When the sensitive material adsorbs acetone vapor, the sensor produces a change in capacitance. The ring oscillator circuit converts the capacitance of the sensor into the oscillation frequency output. The experimental results show that the output frequency of the acetone sensor changes from 128 to 100 MHz as the acetone concentration increases 1 to 70 ppm.

  20. An acetone microsensor with a ring oscillator circuit fabricated using the commercial 0.18 μm CMOS process.

    Science.gov (United States)

    Yang, Ming-Zhi; Dai, Ching-Liang; Shih, Po-Jen

    2014-07-17

    This study investigates the fabrication and characterization of an acetone microsensor with a ring oscillator circuit using the commercial 0.18 μm complementary metal oxide semiconductor (CMOS) process. The acetone microsensor contains a sensitive material, interdigitated electrodes and a polysilicon heater. The sensitive material is α-Fe2O3 synthesized by the hydrothermal method. The sensor requires a post-process to remove the sacrificial oxide layer between the interdigitated electrodes and to coat the α-Fe2O3 on the electrodes. When the sensitive material adsorbs acetone vapor, the sensor produces a change in capacitance. The ring oscillator circuit converts the capacitance of the sensor into the oscillation frequency output. The experimental results show that the output frequency of the acetone sensor changes from 128 to 100 MHz as the acetone concentration increases 1 to 70 ppm.

  1. Micro ethanol sensors with a heater fabricated using the commercial 0.18 μm CMOS process.

    Science.gov (United States)

    Liao, Wei-Zhen; Dai, Ching-Liang; Yang, Ming-Zhi

    2013-09-25

    The study investigates the fabrication and characterization of an ethanol microsensor equipped with a heater. The ethanol sensor is manufactured using the commercial 0.18 µm complementary metal oxide semiconductor (CMOS) process. The sensor consists of a sensitive film, a heater and interdigitated electrodes. The sensitive film is zinc oxide prepared by the sol-gel method, and it is coated on the interdigitated electrodes. The heater is located under the interdigitated electrodes, and it is used to supply a working temperature to the sensitive film. The sensor needs a post-processing step to remove the sacrificial oxide layer, and to coat zinc oxide on the interdigitated electrodes. When the sensitive film senses ethanol gas, the resistance of the sensor generates a change. An inverting amplifier circuit is utilized to convert the resistance variation of the sensor into the output voltage. Experiments show that the sensitivity of the ethanol sensor is 0.35 mV/ppm.

  2. Fabrication of Mutilayered Microgear Using a Vertically Modularized and Sectioned Micromold System by X-ray Micromachining Process

    Science.gov (United States)

    Kim, Jong Hyun; Chang, Suk Sang; Lim, Geunbae; Lee, Bong-Kee

    2011-06-01

    In the present study, a vertically modularized and sectioned micromold system (v-MSMS) is proposed and developed by synchrotron X-ray micromachining process. The developed v-MSMS is a novel concept of constructing a micromold system by stacking several micromold modules. As one representative application of the present v-MSMS, micromold system with several kinds of spur gear patterns was fabricated using deep X-ray lithography and a subsequent nickel electroforming process. Then, the usefulness of v-MSMS was demonstrated by casting the microgear with multiple layers. The proposed technique can be a useful tool for the mass replication of multilayered mechanical components, various micro parts, complicated microstructures, and so on.

  3. Considerations of metal joining processes for space fabrication, construction and repair

    Science.gov (United States)

    Russell, C.; Poorman, R.; Jones, C.; Nunes, A.; Hoffman, D.

    1991-01-01

    A comprehensive evaluation is conducted of candidate processes for metalworking in orbital (vacuum-microgravity) conditions. Attention is given to electron-beam welding, brazing, gas-tungsten arc welding, laser welding, plasma arc welding, and gas-metal arc welding. It is established that several of these processes will be required to cover all foreseeable requirements. Microgravity effects are considered minor, and efforts are being concentrated on problems associated with vacuum conditions and with process-operator safety.

  4. Stress-strain effects in alumina-Cu reinforced Nb3Sn wires fabricated by the tube process

    International Nuclear Information System (INIS)

    Murase, Satoru; Nakayama, Shigeo; Masegi, Tamaki; Koyanagi, Kei; Nomura, Shunji; Shiga, Noriyuki; Kobayashi, Norio; Watanabe, Kazuo.

    1997-01-01

    In order to fabricate a large-bore, high-field magnet which achieves a low coil weight and volume, a high strength compound superconducting wire is required. For those demands we have developed the reinforced Nb 3 Sn wire using alumina dispersion strengthened copper (alumina-Cu) as a reinforcement material and the tube process of the Nb 3 Sn wire fabrication. The ductility study of the composites which consisted of the reinforcement, Nb tube, Cu, and Cu clad Sn brought a 1 km long alumina-Cu reinforced Nb 3 Sn wire successfully. Using fabricated wires measurements and evaluations of critical current density as parameters of magnetic field, tensile stress, tensile strain, and transverse compressive stress, and those of stress-strain curves at 4.2 K were performed. They showed superior performance such as high 0.3% proof stress (240 MPa at 0.3% strain) and high maximum tolerance stress (320 MPa) which were two times as large as those of conventional Cu matrix Nb 3 Sn wire. The strain sensitivity parameters were obtained for the reinforced Nb 3 Sn wire and the Cu matrix one using the scaling law. Residual stress of the component materials caused by cooling down to 4.2 K from heat-treatment temperature was calculated using equivalent Young's modulus, equivalent yield strength, thermal expansion coefficient and other mechanical parameters. Calculated stress-strain curves at 4.2 K for the reinforced Nb 3 Sn wire and the Cu matrix one based on calculation of residual stress, had good agreement with the experimental values. (author)

  5. Fabrication mechanism of FeSe superconductors with high-energy ball milling aided sintering process

    International Nuclear Information System (INIS)

    Zhang, Shengnan; Liu, Jixing; Feng, Jianqing; Wang, Yao; Ma, Xiaobo; Li, Chengshan; Zhang, Pingxiang

    2015-01-01

    FeSe Superconducting bulks with high content of superconducting PbO-type β-FeSe phase were prepared with high-energy ball milling (HEBM) aided sintering process. During this process, precursor powders with certain Fe/Se ratio were ball milled first then sintered. The influences of HEBM process as well as initial Fe/Se ratio on the phase evolution process were systematically discussed. With HEBM process and proper initial Fe/Se ratio, the formation of non-superconducting hexagonal δ-FeSe phase were effectively avoided. FeSe bulk with the critical temperature of 9.0 K was obtained through a simple one-step sintering process with lower sintering temperature. Meanwhile, the phase evolution mechanism of the HEBM precursor powders during sintering was deduced based on both the thermodynamic analysis and step-by-step sintering results. The key function of the HEBM process was to provide a high uniformity of chemical composition distribution, thus to successfully avoide the formation of intermediate product during sintering, including FeSe 2 and Fe 7 Se 8 . Therefore, the fundamental principal for the synthesis of FeSe superconductors were concluded as: HEBM aided sintering process, with the sintering temperature of >635 °C and a slow cooling process. - Highlights: • A novel synthesis technique was developed for FeSe based superconductors. • FeSe bulks with high Tc and high β-FeSe phase content has been obtained. • Phase evolution process for the HEBM aided sintering process was proposed

  6. The flashcal process for the fabrication of fuel-metal oxides using the whiteshell roto-spray calciner

    International Nuclear Information System (INIS)

    Sridhar, T.S.

    1988-01-01

    A one-step, continuous, thermochemical calcination process, called the FLASHCAL (Flash Calcination) process has been developed for the production of single- and mixed-oxide powders of fuel metals (uranium, thorium and plutonium) from the respective nitrate solutions using the Whiteshell Roto-Spray Calciner (RSC). The metal-nitrate feed solution, either by itself or mixed with a suitable chemical reactant or additive, is converted to its oxide powder in the RSC at temperatures between 300 and 600 0 C. Rapid denitration takes place in the calciner, yielding the metal-oxide powders while simultaneously destroying any excess chemical additive and reaction by-products. In the production of precursor oxide powders suitable for fuel fabrication, the FLASHCAL process has advantages over batch calcination and other processes that involve precipitation and filtration steps because fewer processing and handling operations are needed. Results obtained with thorium nitrate and uranium nitrate-thorium nitrate mixtures indicate that some measure of control over the size distribution and morphology of the oxide product powders is possible in this process with the proper selection of chemical additive, as well as the operating parameters of the calciner

  7. Electrospun pH-sensitive core-shell polymer nanocomposites fabricated using a tri-axial process.

    Science.gov (United States)

    Yang, Chen; Yu, Deng-Guang; Pan, Deng; Liu, Xin-Kuan; Wang, Xia; Bligh, S W Annie; Williams, Gareth R

    2016-04-15

    A modified tri-axial electrospinning process was developed for the generation of a new type of pH-sensitive polymer/lipid nanocomposite. The systems produced are able to promote both dissolution and permeation of a model poorly water-soluble drug. First, we show that it is possible to run a tri-axial process with only one of the three fluids being electrospinnable. Using an electrospinnable middle fluid of Eudragit S100 (ES100) with pure ethanol as the outer solvent and an unspinnable lecithin-diclofenac sodium (PL-DS) core solution, nanofibers with linear morphology and clear core/shell structures can be fabricated continuously and smoothly. X-ray diffraction proved that these nanofibers are structural nanocomposites with the drug present in an amorphous state. In vitro dissolution tests demonstrated that the formulations could preclude release in acidic conditions, and that the drug was released from the fibers in two successive steps at neutral pH. The first step is the dissolution of the shell ES100 and the conversion of the core PL-DS into sub-micron sized particles. This frees some DS into solution, and later the remaining DS is gradually released from the PL-DS particles through diffusion. Ex vivo permeation results showed that the composite nanofibers give a more than twofold uplift in the amount of DS passing through the colonic membrane as compared to pure DS; 74% of the transmitted drug was in the form of PL-DS particles. The new tri-axial electrospinning process developed in this work provides a platform to fabricate structural nanomaterials, and the core-shell polymer-PL nanocomposites we have produced have significant potential applications for oral colon-targeted drug delivery. A modified tri-axial electrospinning is demonstrated to create a new type of core-shell pH-sensitive polymer/lipid nanocomposites, in which an electrospinnable middle fluid is exploited to support the un-spinnable outer and inner fluids. The structural nanocomposites are able

  8. Optimized Compositional Design and Processing-Fabrication Paths for Larger Heats of Nanostructured Ferritic Alloys

    Energy Technology Data Exchange (ETDEWEB)

    Odette, G. Robert [Univ. of California, Santa Barbara, CA (United States)

    2017-02-06

    The objective of this work was to characterize the alloy 14YWT-PM2, which is an extruded and cross-rolled precursor alloy to a large heat of 14YWT being produced using an alternative processing path that incorporates Y during gas atomization process.

  9. Process chain for fabrication of anisotropic optical functional surfaces on polymer components

    DEFF Research Database (Denmark)

    Li, Dongya; Zhang, Yang; Regi, Francesco

    2017-01-01

    from a certain viewing angle. The process chain comprised three steps: tooling, replicationand quality assurance. Tooling was achieved by precision micro milling. Replication processes such as injection moulding, hotembossing, blow moulding, etc. were employed according to the specific type of product...

  10. High performance poly(etherketoneketone) (PEKK) composite parts fabricated using Big Area Additive Manufacturing (BAAM) processes

    Energy Technology Data Exchange (ETDEWEB)

    Kunc, Vlastimil [ORNL; Kishore, Vidya [ORNL; Chen, Xun [ORNL; Ajinjeru, Christine [ORNL; Duty, Chad [University of Tennessee (UTK) and Oak Ridge National Laboratory (ORNL); Hassen, Ahmed A [ORNL

    2016-09-01

    ORNL collaborated with Arkema Inc. to investigate poly(etherketoneketone) (PEKK) and its composites as potential feedstock material for Big Area Additive Manufacturing (BAAM) system. In this work thermal and rheological properties were investigated and characterized in order to identify suitable processing conditions and material flow behavior for BAAM process.

  11. Decolorization and degradation of reactive dye during the dyed cotton fabric rinsing process.

    Science.gov (United States)

    Luo, Deng-Hong; Zheng, Qing-Kang; Chen, Sheng; Liu, Qing-Shu; Wang, Xiu-Xing; Guan, Yu; Pu, Zong-Yao

    2010-01-01

    Dyeing process of textile consumes large quantities of water, which results in huge amounts of colored wastewater. Most of the dye wastewater treating methods focused on the treatment of wastewater after the rinsing process of dyed textile. In this paper, tetraacetylethylenediamine/hydrogen peroxide (TAED/H₂O₂) active oxidation (AO) system was developed to rinse dyed textile and decolorize the rinsing wastewater simultaneously. The results indicated that the decolorization ratio of the rinse effluent obtained by AO method were in the range of 51.72%-84.15% according to different dyes and the COD value decreased more than 30% compared with that of traditional rinsing process. The decolorization kinetics investigation showed that the decolorization of dyes during AO rinsing process followed the law of pseudo-first order kinetics. The result of UV-Vis and UPLC-MS analysis demonstrated that the dye was degraded into colorless organic molecular fragments and partly mineralized during the AO rinsing process.

  12. Perception Of The Nurse In The Process Of Donation Of Organs And Fabrics For Transplantation

    Directory of Open Access Journals (Sweden)

    Vanessa Vargas

    2017-06-01

    Full Text Available Objective: to know the nurses' perception in the process of organ and tissue donation for transplants. Methods: qualitative research with data collection performed through a semistructured interview with 16 nurses from a hospital. The data were submitted to Bardin content analysis. Results: categories emerged after content analysis were as follows: Organ donation process: nurses' experience; Nursing care for potential donors; Family approach; Main difficulties in the donation process. Conclusion: the research demonstrated the real difficulties of the professionals during the donation process, such as lack of human resources, extensive protocols, and lack of awareness of the society to understand the donation process and the family approach. Keywords: Transplantation of Organs; Obtaining Tissues and Organs; Nursing care.

  13. Thermal processing of strained silicon-on-insulator for atomically precise silicon device fabrication

    International Nuclear Information System (INIS)

    Lee, W.C.T.; Bishop, N.; Thompson, D.L.; Xue, K.; Scappucci, G.; Cederberg, J.G.; Gray, J.K.; Han, S.M.; Celler, G.K.; Carroll, M.S.; Simmons, M.Y.

    2013-01-01

    Highlights: ► Strained silicon-on-insulator (sSOI) samples were flash-annealed at high temperature under ultra-high vacuum conditions. ► The extend of surface strain relaxation depends on the annealing temperature with no strain relaxation observed below 1020 °C. ► A 2 × 1 reconstructed surface with low defect density can be achieved. ► The annealed sSOI surface shows enhanced step undulations due to the unique energetics caused by surface strain. - Abstract: We investigate the ability to reconstruct strained silicon-on-insulator (sSOI) substrates in ultra-high vacuum for use in atomic scale device fabrication. Characterisation of the starting sSOI substrate using μRaman shows an average tensile strain of 0.8%, with clear strain modulation in a crosshatch pattern across the surface. The surfaces were heated in ultra-high vacuum from temperatures of 900 °C to 1100 °C and subsequently imaged using scanning tunnelling microscopy (STM). The initial strain modulation on the surface is observed to promote silicon migration and the formation of crosshatched surface features whose height and pitch increases with increasing annealing temperature. STM images reveal alternating narrow straight S A steps and triangular wavy S B steps attributed to the spontaneous faceting of S B and preferential adatom attachment on S B under biaxial tensile strain. Raman spectroscopy shows that despite these high temperature anneals no strain relaxation of the substrate is observed up to temperatures of 1020 °C. Above 1100 °C, strain relaxation is evident but is confined to the surface.

  14. Fabrication and processing of polymer solar cells: A review of printing and coating techniques

    DEFF Research Database (Denmark)

    Krebs, Frederik C

    2009-01-01

    Polymer solar cells are reviewed in the context of the processing techniques leading to complete devices. A distinction is made between the film-forming techniques that are used currently such as spincoating, doctor blading and casting and the, from a processing point of view, more desirable film...... suited, but little explored in the context of polymer solar cells. A further distinction is made between printing and coating when a film is formed. The entire process leading to polymer solar cells is broken down into the individual steps and the available techniques and materials for each step...

  15. CHARACTERIZATION OF MICRO/NANO POROUS HOLLOW GLASS MICROSPHERES FABRICATED THROUGH VARIOUS CHEMICAL ETCHING PROCESSE FOR USE IN SMART COATINGS

    Directory of Open Access Journals (Sweden)

    T. Ebrahimi Sadrabadi

    2016-12-01

    Full Text Available Porous hollow glass microspheres have many uses, including encapsulation of active materials. In this paper a fast and facile method for fabricating porous hollow glass-microspheres was demonstrated by etching them using dilute hydrofluoric acid. Then, a highly reactive amine was infiltrated into the etched glass microspheres. Scanning electron microscopy was conducted for the hollow glass microspheres prior and post etching process. With regards to the porous hollow glass spherical sample, the spherical nature, morphology, pore diameter and the porosity were studied using scanning electron microscopy. Formation of the intact hollow glass microspheres with an open through wall porosities following phase separation and etching of the boron oxide rich phase was demonstrated using reciprocating shaker as the most suitable agitation method. The BET results indicated that the surface of the porous microspheres contained nano-pores. It is believed that the simplicity of the reported fabrication technique of micro/nano porous structure has the potential to scaling up for large scale production

  16. An assessment of the process of Self-propagating High-Temperature Synthesis for the fabrication of porous copper composite

    International Nuclear Information System (INIS)

    Moloodi, A.; Raiszadeh, R.; Vahdati-Khaki, J.; Babakhani, A.

    2009-01-01

    The present article describes the process of Self-propagating High-temperature Synthesis (SHS) that is employed for fabricating open cell copper-alumina composite foam. This foam was fabricated by the reactions between the powders of CuO, Al and C. The gas released during these reactions as well as the initial porosity of the green powder compact were suggested to be the sources of the produced pores. Further, the effect of C content and the precursor compressing pressure on the porosity content and morphology of the SHS product was determined. Optical microscopy (OM), scanning electron microscopy (SEM), and X-ray diffraction (XRD) were utilized to characterize the porous samples. The optimum weight fractions for blending the initial powders were determined to be 84 wt.% CuO, 9.5 wt.% Al, and 6.5 wt.% C, and the SHS reaction was sustainable only if the initial compacting pressure of the powders was between 100 and 300 MPa.

  17. "Fabrication of arbitrarily shaped carbonate apatite foam based on the interlocking process of dicalcium hydrogen phosphate dihydrate".

    Science.gov (United States)

    Sugiura, Yuki; Tsuru, Kanji; Ishikawa, Kunio

    2017-08-01

    Carbonate apatite (CO 3 Ap) foam with an interconnected porous structure is highly attractive as a scaffold for bone replacement. In this study, arbitrarily shaped CO 3 Ap foam was formed from α-tricalcium phosphate (α-TCP) foam granules via a two-step process involving treatment with acidic calcium phosphate solution followed by hydrothermal treatment with NaHCO 3 . The treatment with acidic calcium phosphate solution, which is key to fabricating arbitrarily shaped CO 3 Ap foam, enables dicalcium hydrogen phosphate dihydrate (DCPD) crystals to form on the α-TCP foam granules. The generated DCPD crystals cause the α-TCP granules to interlock with each other, inducing an α-TCP/DCPD foam. The interlocking structure containing DCPD crystals can survive hydrothermal treatment with NaHCO 3 . The arbitrarily shaped CO 3 Ap foam was fabricated from the α-TCP/DCPD foam via hydrothermal treatment at 200 °C for 24 h in the presence of a large amount of NaHCO 3 .

  18. Fabrication of a 77 GHz Rotman Lens on a High Resistivity Silicon Wafer Using Lift-Off Process

    Directory of Open Access Journals (Sweden)

    Ali Attaran

    2014-01-01

    Full Text Available Fabrication of a high resistivity silicon based microstrip Rotman lens using a lift-off process has been presented. The lens features 3 beam ports, 5 array ports, 16 dummy ports, and beam steering angles of ±10 degrees. The lens was fabricated on a 200 μm thick high resistivity silicon wafer and has a footprint area of 19.7 mm × 15.6 mm. The lens was tested as an integral part of a 77 GHz radar where a tunable X band source along with an 8 times multiplier was used as the RF source and the resulting millimeter wave signal centered at 77 GHz was radiated through a lens-antenna combination. A horn antenna with a downconverter harmonic mixer was used to receive the radiated signal and display the received signal in an Advantest R3271A spectrum analyzer. The superimposed transmit and receive signal in the spectrum analyzer showed the proper radar operation confirming the Rotman lens design.

  19. Characterization of the high density plasma etching process of CCTO thin films for the fabrication of very high density capacitors

    Energy Technology Data Exchange (ETDEWEB)

    Altamore, C; Tringali, C; Sparta' , N; Marco, S Di; Grasso, A; Ravesi, S [STMicroelectronics, Industial and Multi-segment Sector R and D, Catania (Italy)

    2010-02-15

    In this work the feasibility of CCTO (Calcium Copper Titanate) patterning by etching process is demonstrated and fully characterized in a hard to etch materials etcher. CCTO sintered in powder shows a giant relative dielectric constant (10{sup 5}) measured at 1 MHz at room temperature. This feature is furthermore coupled with stability from 10{sup 1} Hz to 10{sup 6} Hz in a wide temperature range (100K - 600K). In principle, this property can allow to fabricate very high capacitance density condenser. Due to its perovskite multi-component structure, CCTO can be considered a hard to etch material. For high density capacitor fabrication, CCTO anisotropic etching is requested by using high density plasma. The behavior of etched CCTO was studied in a HRe- (High Density Reflected electron) plasma etcher using Cl{sub 2}/Ar chemistry. The relationship between the etch rate and the Cl{sub 2}/Ar ratio was also studied. The effects of RF MHz, KHz Power and pressure variation, the impact of HBr addiction to the Cl{sub 2}/Ar chemistry on the CCTO etch rate and on its selectivity to Pt and photo resist was investigated.

  20. Feasibility investigations on multi-cutter milling process: A novel fabrication method for microreactors with multiple microchannels

    Science.gov (United States)

    Pan, Minqiang; Zeng, Dehuai; Tang, Yong

    A novel multi-cutter milling process for multiple parallel microchannels with manifolds is proposed to address the challenge of mass manufacture as required for cost-effective commercial applications. Several slotting cutters are stacked together to form a composite tool for machining microchannels simultaneously. The feasibility of this new fabrication process is experimentally investigated under different machining conditions and reaction characteristics of methanol steam reforming for hydrogen production. The influences of cutting parameters and the composite tool on the microchannel qualities and burr formation are analyzed. Experimental results indicate that larger cutting speed, smaller feed rate and cutting depth are in favor of obtaining relatively good microchannel qualities and small burrs. Of all the cutting parameters considered in these experiments, 94.2 m min -1 cutting speed, 23.5 mm min -1 feed rate and 0.5 mm cutting depth are found to be the optimum value. According to the comparisons of experimental results of multi-cutter milling process and estimated one of other alternative methods, it is found that multi-cutter milling process shows much shorter machining time and higher work removal rate than that of other alternative methods. Reaction characteristics of methanol steam reforming in microchannels also indicate that multi-cutter milling process is probably suitable for a commercial application.

  1. Machine learning and predictive data analytics enabling metrology and process control in IC fabrication

    Science.gov (United States)

    Rana, Narender; Zhang, Yunlin; Wall, Donald; Dirahoui, Bachir; Bailey, Todd C.

    2015-03-01

    Integrate circuit (IC) technology is going through multiple changes in terms of patterning techniques (multiple patterning, EUV and DSA), device architectures (FinFET, nanowire, graphene) and patterning scale (few nanometers). These changes require tight controls on processes and measurements to achieve the required device performance, and challenge the metrology and process control in terms of capability and quality. Multivariate data with complex nonlinear trends and correlations generally cannot be described well by mathematical or parametric models but can be relatively easily learned by computing machines and used to predict or extrapolate. This paper introduces the predictive metrology approach which has been applied to three different applications. Machine learning and predictive analytics have been leveraged to accurately predict dimensions of EUV resist patterns down to 18 nm half pitch leveraging resist shrinkage patterns. These patterns could not be directly and accurately measured due to metrology tool limitations. Machine learning has also been applied to predict the electrical performance early in the process pipeline for deep trench capacitance and metal line resistance. As the wafer goes through various processes its associated cost multiplies. It may take days to weeks to get the electrical performance readout. Predicting the electrical performance early on can be very valuable in enabling timely actionable decision such as rework, scrap, feedforward, feedback predicted information or information derived from prediction to improve or monitor processes. This paper provides a general overview of machine learning and advanced analytics application in the advanced semiconductor development and manufacturing.

  2. A sustainable and green process for scouring of cotton fabrics using xylano-pectinolytic synergism: switching from noxious chemicals to eco-friendly catalysts.

    Science.gov (United States)

    Singh, Avtar; Kaur, Amanjot; Patra, Arun Kumar; Mahajan, Ritu

    2018-04-01

    The objective of this research was to develop an appropriate, eco-friendly, cost-effective bioscouring methodology for removing natural impurities from cotton fabric. Maximum bioscouring was achieved using 5.0 IU xylanase and 4.0 IU pectinase with material to liquid ratio of 1:15 in a 50 mM buffer (glycine-NaOH buffer, 1.0 mM EDTA and 1% Tween-80, pH 8.5) with a treatment time of 60 min at 50 °C and an agitation speed of 60 rpm. The bioscoured cotton fabrics showed a gain of 1.17% in whiteness, 3.23% in brightness and a reduction of 4.18% in yellowness in comparison to fabric scoured with an alkaline scouring method. Further, after bleaching, the whiteness, brightness and tensile strength of the bioscoured fabrics were increased by 2.18, 2.33 and 11.74% along with a decrease of 4.61% in yellowness of bioscoured plus bleached fabrics in comparison to chemically scoured plus bleached fabrics. From the results, it is clear that bioscouring is more efficient, energy saving and an eco-friendly process and has the potential to replace the environment-damaging scouring process with the xylano-pectinolytic bioscouring process.

  3. Development of Cotton Fabrics with Durable UV Protective and Self-cleaning Property by Deposition of Low TiO2Levels through Sol-gel Process.

    Science.gov (United States)

    Mishra, Anu; Butola, Bhupendra Singh

    2018-01-19

    In this article, the deposition of TiO 2 on cotton fabric using sol-gel technique has been described. Various process routes (pad-dry-cure, pad-dry-hydrothermal and pad-dry-solvothermal) were examined to impart a stable coating of TiO 2 on fabric. The role of precursor concentration, process temperature and time of treatment were studied to aim at a wash durable, UV protective and self-cleaning property in the treated fabric. EDX and ICP-MS techniques were used to examine the add-on percentage of TiO 2 on cotton fabrics treated via different routes. It has been found that the TiO 2 remains largely amorphous and nondurable if it is given a short thermal treatment. To convert the deposited TiO 2 to its anatase crystal form, a prolonged hydrothermal treatment for at least 3 h needs to be given. TiO 2 deposition levels of less than 0.1% were found to be effective in imparting reasonable degree of UV protection and self-cleaning property to the cotton fabric. The self-cleaning ability of the treated fabric against coffee stain was also studied and was found to be related to the process route and the deposition levels of TiO 2 . © 2018 The American Society of Photobiology.

  4. The analysis of the wax foundry models fabrication process for the CPX3000 device

    Directory of Open Access Journals (Sweden)

    G. Budzik

    2011-04-01

    Full Text Available The paper presents possibilities of creating wax founding models by means of CPX3000 device. The device is used for Rapid Prototypingof models made of foundry wax in an incremental process. The paper also presents problems connected with choosing technologicalparameters for incremental shaping which influence the accuracy of created models. Issues connected with post-processing are alsodescribed. This process is of great importance for obtaining geometrically correct models. The analysis of parameters of cleaning models from supporting material is also presented. At present CPX3000 printer is the first used in Poland device by 3D Systems firm for creating wax models. The printer is at The Faculty of Mechanical Engineering at Rzeszów University of Technology.

  5. Analysis and prediction of dimensions and cost of laser micro-machining internal channel fabrication process

    Directory of Open Access Journals (Sweden)

    Brabazon D.

    2010-06-01

    Full Text Available This paper presents the utilisation of Response Surface Methodology (RSM as the prediction tool for the laser micro-machining process. Laser internal microchannels machined using pulsed Nd:YVO4 laser in polycarbonate were investigated. The experiments were carried out according to 33 factorial Design of Experiment (DoE. In this work the three input process set as control parameters were laser power, P; pulse repetition frequency, PRF; and sample translation speed, U. Measured responses were the channel width and the micro-machining operating cost per metre of produced microchannels. The responses were sufficiently predicted within the set micro-machining parameters limits. Two factorial interaction (2FI and quadratic polynomial regression equations for both responses were constructed. It is proposed that the developed prediction equations can be used to find locally optimal micro-machining process parameters under experimental and operational conditions.

  6. Micro-EDM process modeling and machining approaches for minimum tool electrode wear for fabrication of biocompatible micro-components

    DEFF Research Database (Denmark)

    Puthumana, Govindan

    2017-01-01

    Micro-electrical discharge machining (micro-EDM) is a potential non-contact method for fabrication of biocompatible micro devices. This paper presents an attempt to model the tool electrode wear in micro-EDM process using multiple linear regression analysis (MLRA) and artificial neural networks...... linear regression model was developed for prediction of TWR in ten steps at a significance level of 90%. The optimum architecture of the ANN was obtained with 7 hidden layers at an R-sq value of 0.98. The predicted values of TWR using ANN matched well with the practically measured and calculated values...... (ANN). The governing micro-EDM factors chosen for this investigation were: voltage (V), current (I), pulse on time (Ton) and pulse frequency (f). The proposed predictive models generate a functional correlation between the tool electrode wear rate (TWR) and the governing micro-EDM factors. A multiple...

  7. Effects of furnace atmosphere pressure on fabrication process of hollow glass microspheres in drop-tower furnace

    International Nuclear Information System (INIS)

    Qi Xiaobo; Li Bo; Chen Sufen; Zhang Zhanwen; Shi Tao

    2010-01-01

    To fabricate high quality hollow glass microspheres (HGMs)by sol-gel technology for inertial confinement fusion (ICF), the effects of furnace atmosphere pressure on the transformation process from gel particles to HGMs and the resulting quality of HGMs were investigated by numerical simulation and experiments. The results show that decreasing of furnace atmosphere pressure can increase diameter of HGMs and decrease wall thickness of HGMs. Decreasing furnace atmosphere pressure can extend the refining time of liquid HGMs, however, the heat transfer coefficient between liquid and furnace atmosphere pressure decreases significantly with the decreasing of furnace atmosphere pressure. As a result, the refining degree and the quality of HGMs descend quickly with furnace atmosphere pressure. When the furnace atmosphere pressure is lower than 0.5 x 10 5 Pa, the sphericity, concentricity and surface finish can not satisfy the restrict requirements of ICF targets. (authors)

  8. Split CV mobility at low temperature operation of Ge pFinFETs fabricated with STI first and last processes

    Science.gov (United States)

    Oliveira, A. V.; Simoen, E.; Agopian, P. G. D.; Martino, J. A.; Mitard, J.; Witters, L.; Langer, R.; Collaert, N.; Thean, A.; Claeys, C.

    2016-11-01

    The effective hole mobility of long strained Ge pFinFETs, fabricated with shallow trench isolation (STI) first and last approaches, is systematically evaluated from room temperature down to 77 K, from planar-like (100 nm) to narrow (20 nm) devices. The goal is to identify the dominant scattering mechanism. Here, the split capacitance-voltage (CV) technique has been applied, based on combined current-voltage (I-V) and CV measurements. It is shown that even at 77 K, the phonon scattering mechanism dominates the STI last process, while the Coulomb scattering strongly affects the STI first approach. On the other hand, the latter shows slightly higher hole mobility compared to the STI last counterpart.

  9. Fabrication of mesoporous silica/polymer composites through solvent evaporation process and investigation of their excellent low thermal expansion property.

    Science.gov (United States)

    Suzuki, Norihiro; Kiba, Shosuke; Yamauchi, Yusuke

    2011-03-21

    We fabricate mesoporous silica/epoxy polymer composites through a solvent evaporation process. The easy penetration of the epoxy polymers into mesopores is achieved by using a diluted polymer solution including a volatile organic solvent. After the complete solvent evaporation, around 90% of the mesopores are estimated to be filled with the epoxy polymer chains. Here we carefully investigate the thermal expansion behavior of the obtained mesoporous silica/polymer composites. Thermal mechanical analysis (TMA) charts revealed that coefficient of linear thermal expansion (CTE) gradually decreases, as the amount of the doped mesoporous silica increases. Compared with spherical silica particle without mesopores, mesoporous silica particles show a greater effect on lowering the CTE values. Interestingly, it is found that the CTE values are proportionally decreased with the decrease of the total amount of the polymers outside the mesopores. These data demonstrate that polymers embedded inside the mesopores become thermally stable, and do not greatly contribute to the thermal expansion behavior of the composites.

  10. Problems in the development of high-energy radiation processing of woven and knitted fabrics

    International Nuclear Information System (INIS)

    Ihme, B.; Maeder, E.; Mally, S.

    1983-01-01

    The modification of hygienic properties of garments made of polyamide and polyester planar structures has been investigated. The results underline the fact that radiation-induced modification aimed at increasing the serviceability of textile planar structures is a relatively complicated process of textile finishing resulting in the need of additional chemicals, facilities, manpower, and energy. (author)

  11. Fabrication and simulation of glass micromachining using CO2 laser processing with PDMS protection

    Science.gov (United States)

    Chung, C. K.; Lin, S. L.; Wang, H. Y.; Tan, T. K.; Tu, K. Z.; Lung, H. F.

    2013-11-01

    Traditional glass micromachining using laser processing in air would produce many kinds of defects, such as bulges, debris, micro-cracks and scorches. In this article, a poly-dimethylsiloxane (PDMS) protection processing has been presented to reduce the temperature gradient and heat-affected zone (HAZ) to achieve crack-free Pyrex glass machining. A good quality of etched surface which is a clear and much-reduced bulge without crack and scorch is achieved using CO2 laser micromachining at 150 μm thick PDMS protection layer and the laser powers of 10-15 W and scanning speeds of 228-342 mm/s for five passes. The PDMS cover layer benefits feature size and bulge height reduction. The alpha-step measured profile shows that the much reduced bulge height around the rims of channel was about 1.2 μm at 150 μm thick PDMS about 13 times smaller than that in air. The ANSYS software was used to analyze the temperature distribution and thermal stress field of glass micromachining in air without and with PDMS cover layer. The smaller temperature gradient observed in PDMS protection processing has the smaller HAZ and diminishes the crack formation during the laser processing.

  12. A simulated RTM process for fabricating polyimide (AMB-21) carbon fiber composites

    Science.gov (United States)

    Avva, V. Sarma; Sadler, Robert L.; Thomas, Shanon

    1995-01-01

    An experimental polyimide matrix, AMB-21 - supplied by NASA/LeRC, was especially formulated to be non-carcinogenic. It was also expected to be amenable to a Resin Transfer Molding Process (RTM). AMB-21 is a solid at room temperature and must be heated to a very high temperature to obtain a fluid state. However, even after heating it to a realistic high temperature, it was found to be too viscous for use in a RTM process. As a result, a promising approach was experimented leading to the introduction of the resin into a solvent solution in order to obtain a viscosity suitable for RTM. A mixture of methanol and tetrahydroferone was found to be a suitable solvent mixture. The matrix solution was introduced into carbon-fiber preform using two techniques: (1) injection of matrix into a Resin Transfer Mold after positioning the preform into the 'mold cavity', and (2) infiltration of matrix into the preform using the 'autoclave through-the-thickness transfer process'. After completing the resin transfer (infiltration) process, the 'filled' preform was heated to 300 F for one hour to reduce the solvent content. The temperature was then increased to 400 F under a vacuum to complete the solvent evaporation and to remove volatile products of the polyimide imidization. The impregnated preform was removed from the mold and press-cured at 200 psi and 600 FF for two hours. The resulting panel was found to be of reasonably good quality. This observation was based on the results obtained from short beam shear strength (700-8000 psi) tests and microscopic examination of the cross-section indicating a very low level of porosity. Further, the flash around the molded panels from the compression molding was free of porosity indicating the removal of volatiles, solvents, and other imidization products. Based on these studies, a new RTM mold containing a diaphragm capable of applying 200 psi at 600 F has been designed and constructed with the expectation that it will allow the

  13. Microstructure and Mechanical Properties of Ultra-Fine Grain Al-Zr Alloy Fabricated by Mechanical Alloying Process.

    Science.gov (United States)

    Kim, Chung Seok; Kim, Il-Ho

    2015-08-01

    The ultra-fine grain Al-4Zr alloy has been successfully fabricated by a mechanical alloying process. The intermetallic Al3Zr phases strongly enhance the mechanical properties of Al-based alloy and prevent grain growth of alloy. The phase stability and transformation during mechanical alloying process have been investigated. The ultra-fine grain alloy has been successfully obtained. The thin film of Al-4Zr alloy has been observed by a transmission electron microscope. The equivalent grain size of as-milling specimen is 55 nm. After milling process, the specimens were heat treated at 350 °C to 650 °C. The equivalent grain size of heat treated specimens were 80 nm at 350 °C and 130 nm at 650 °C. Some of Zr atoms were dissolved into the Al matrix and most of them reacted with hydrogen produced by decomposition of PCA to form ZrH2 during mechanical alloying process. These ZrH2 hydrides decomposed gradually after the heat treatment. Stable A13Zr with a D023 structure was formed by heat treatment at temperature of 550 °C.

  14. The fabrication of a process heat exchanger for a SO3 decomposer using surface-modified hastelloy X materials

    International Nuclear Information System (INIS)

    Park, Jae Won; Kim, Hyung Jin; Kim Yong Wan

    2008-01-01

    This study investigates the surface modification of a Hastelloy X plate and diffusion bonding in the assembly of surface modified plates. These types of plates are involved in the key processes in the fabrication of a Process Heat Exchanger (PHE) for a SO 3 decomposer. Strong adhesion of a SiC film deposited onto Hastelloy X can be achieved by a thin SiC film deposition and a subsequent N ion beam bombardment followed by an additional deposition of a thicker film that prevents the Hastelloy X surface from becoming exposed to a corrosive environment through the pores. This process not only produces higher corrosion resistance as proved by electrolytic etching but also exhibits higher endurance against thermal stress above 900 .deg. C. A process for a good bonding between Hastelloy X sheets, which is essential for a good heat exchanger, was developed by diffusion bonding. The diffusion bonding was done by mechanically clamping the sheets under a heat treatment at 900 .deg. C. When the clamping jig consisted of materials with a thermal expansion coefficient that was equal to or less than that of the Hastelloy X, sound bonding was achieved

  15. A rapid process of Yba2Cu3O7-δ thin film fabrication using trifluoroacetate metal-organic deposition with polyethylene glycol additive

    DEFF Research Database (Denmark)

    Wu, Wei; Feng, Feng; Shi, Kai

    2013-01-01

    Trifluoroacetate metal-organic deposition (TFA-MOD) is a promising technique to fabricate YBa2Cu3O7-δ (YBCO) superconducting films. However, its slow pyrolysis process, which usually takes more than 10 h, constitutes a barrier for industrial production. In this study, polyethylene glycol (PEG...... and oxygenation processes, mass percentage and molecular weight of PEG additive, YBCO thin films with Jc of about 4.5 MA cm-2 (77 K, self-field) could be routinely fabricated using (20-30) wt% PEG(1000-2000) additive with a total treatment time of about 2 h including the 15 min pyrolysis process time. The effects...

  16. Process Development And Simulation For Cold Fabrication Of Doubly Curved Metal Plate By Using Line Array Roll Set

    Science.gov (United States)

    Shim, D. S.; Jung, C. G.; Seong, D. Y.; Yang, D. Y.; Han, J. M.; Han, M. S.

    2007-05-01

    For effective manufacturing of a doubly curved sheet metal, a novel sheet metal forming process is proposed. The suggested process uses a Line Array Roll Set (LARS) composed of a pair of upper and lower roll assemblies in a symmetric manner. The process offers flexibility as compared with the conventional manufacturing processes, because it does not require any complex-shaped die and loss of material by blank-holding is minimized. LARS allows flexibility of the incremental forming process and adopts the principle of bending deformation, resulting in a slight deformation in thickness. Rolls composed of line array roll sets are divided into a driving roll row and two idle roll rows. The arrayed rolls in the central lines of the upper and lower roll assemblies are motor-driven so that they deform and transfer the sheet metal using friction between the rolls and the sheet metal. The remaining rolls are idle rolls, generating bending deformation with driving rolls. Furthermore, all the rolls are movable in any direction so that they are adaptable to any size or shape of the desired three-dimensional configuration. In the process, the sheet is deformed incrementally as deformation proceeds simultaneously in rolling and transverse directions step by step. Consequently, it can be applied to the fabrication of doubly curved ship hull plates by undergoing several passes. In this work, FEM simulations are carried out for verification of the proposed incremental forming system using the chosen design parameters. Based on the results of the simulation, the relationship between the roll set configuration and the curvature of a sheet metal is determined. The process information such as the forming loads and torques acting on every roll is analyzed as important data for the design and development of the manufacturing system.

  17. Process Development And Simulation For Cold Fabrication Of Doubly Curved Metal Plate By Using Line Array Roll Set

    International Nuclear Information System (INIS)

    Shim, D. S.; Jung, C. G.; Seong, D. Y.; Yang, D. Y.; Han, J. M.; Han, M. S.

    2007-01-01

    For effective manufacturing of a doubly curved sheet metal, a novel sheet metal forming process is proposed. The suggested process uses a Line Array Roll Set (LARS) composed of a pair of upper and lower roll assemblies in a symmetric manner. The process offers flexibility as compared with the conventional manufacturing processes, because it does not require any complex-shaped die and loss of material by blank-holding is minimized. LARS allows flexibility of the incremental forming process and adopts the principle of bending deformation, resulting in a slight deformation in thickness. Rolls composed of line array roll sets are divided into a driving roll row and two idle roll rows. The arrayed rolls in the central lines of the upper and lower roll assemblies are motor-driven so that they deform and transfer the sheet metal using friction between the rolls and the sheet metal. The remaining rolls are idle rolls, generating bending deformation with driving rolls. Furthermore, all the rolls are movable in any direction so that they are adaptable to any size or shape of the desired three-dimensional configuration. In the process, the sheet is deformed incrementally as deformation proceeds simultaneously in rolling and transverse directions step by step. Consequently, it can be applied to the fabrication of doubly curved ship hull plates by undergoing several passes. In this work, FEM simulations are carried out for verification of the proposed incremental forming system using the chosen design parameters. Based on the results of the simulation, the relationship between the roll set configuration and the curvature of a sheet metal is determined. The process information such as the forming loads and torques acting on every roll is analyzed as important data for the design and development of the manufacturing system

  18. Crystalline Ceramic Waste Forms: Comparison Of Reference Process For Ceramic Waste Form Fabrication

    Energy Technology Data Exchange (ETDEWEB)

    Brinkman, K. S. [Savannah River National Laboratory; Marra, J. C. [Savannah River National Laboratory; Amoroso, J. [Savannah River National Laboratory; Tang, M. [Los Alamos National Laboratory

    2013-08-22

    The research conducted in this work package is aimed at taking advantage of the long term thermodynamic stability of crystalline ceramics to create more durable waste forms (as compared to high level waste glass) in order to reduce the reliance on engineered and natural barrier systems. Durable ceramic waste forms that incorporate a wide range of radionuclides have the potential to broaden the available disposal options and to lower the storage and disposal costs associated with advanced fuel cycles. Assemblages of several titanate phases have been successfully demonstrated to incorporate radioactive waste elements, and the multiphase nature of these materials allows them to accommodate variation in the waste composition. Recent work has shown that they can be produced from a melting and crystallization process. The objective of this report is to explore the phase formation and microstructural differences between lab scale melt processing in varying gas environments with alternative densification processes such as Hot Pressing (HP) and Spark Plasma Sintering (SPS). The waste stream used as the basis for the development and testing is a simulant derived from a combination of the projected Cs/Sr separated stream, the Trivalent Actinide - Lanthanide Separation by Phosphorous reagent Extraction from Aqueous Komplexes (TALSPEAK) waste stream consisting of lanthanide fission products, the transition metal fission product waste stream resulting from the transuranic extraction (TRUEX) process, and a high molybdenum concentration with relatively low noble metal concentrations. Melt processing as well as solid state sintering routes SPS and HP demonstrated the formation of the targeted phases; however differences in microstructure and elemental partitioning were observed. In SPS and HP samples, hollandite, pervoskite/pyrochlore, zirconolite, metallic alloy and TiO{sub 2} and Al{sub 2}O{sub 3} were observed distributed in a network of fine grains with small residual pores

  19. Dynamic metrology and data processing for precision freeform optics fabrication and testing

    Science.gov (United States)

    Aftab, Maham; Trumper, Isaac; Huang, Lei; Choi, Heejoo; Zhao, Wenchuan; Graves, Logan; Oh, Chang Jin; Kim, Dae Wook

    2017-06-01

    Dynamic metrology holds the key to overcoming several challenging limitations of conventional optical metrology, especially with regards to precision freeform optical elements. We present two dynamic metrology systems: 1) adaptive interferometric null testing; and 2) instantaneous phase shifting deflectometry, along with an overview of a gradient data processing and surface reconstruction technique. The adaptive null testing method, utilizing a deformable mirror, adopts a stochastic parallel gradient descent search algorithm in order to dynamically create a null testing condition for unknown freeform optics. The single-shot deflectometry system implemented on an iPhone uses a multiplexed display pattern to enable dynamic measurements of time-varying optical components or optics in vibration. Experimental data, measurement accuracy / precision, and data processing algorithms are discussed.

  20. Thixo forging process of wrought aluminum alloy fabricated by rotational helical shape stirrer

    International Nuclear Information System (INIS)

    Lee, S. M.; Han, S. H.; Kang, C. G.

    2007-01-01

    The manufacture of rheology materials from wrought and casting aluminum alloys using controlling solid fraction and crystal grain is demonstrated in this paper. The equipment to form the rheology material was designed so that shear force and applied pressure could be carefully and simultaneously applied using a mechanical stirrer. The problems caused by using this method with the thixo forging process were studied by investigating the mechanical properties of a sample that had a controlled solid fraction of 45-50 %

  1. Laser process and corresponding structures for fabrication of solar cells with shunt prevention dielectric

    Energy Technology Data Exchange (ETDEWEB)

    Harley, Gabriel; Smith, David D.; Dennis, Tim; Waldhauer, Ann; Kim, Taeseok; Cousins, Peter John

    2017-11-28

    Contact holes of solar cells are formed by laser ablation to accommodate various solar cell designs. Use of a laser to form the contact holes is facilitated by replacing films formed on the diffusion regions with a film that has substantially uniform thickness. Contact holes may be formed to deep diffusion regions to increase the laser ablation process margins. The laser configuration may be tailored to form contact holes through dielectric films of varying thicknesses.

  2. Tube with helical grooves for heat transfer and its fabrication process

    International Nuclear Information System (INIS)

    Yampolsky, J.S.

    1977-01-01

    The invention suggests a thermal transfer tube for use in a heat exchanger. The wall of the tube includes a certain number of spiral or helical, internal and external, grooves for the flow of the heat exchange fluids along the tube. The grooves extend for the full length of the tube. They are uniform in design and mark the internal and external spiral hollows and crests. A process for the manufacture of the heat transfer tube is also included in the invention [fr

  3. Process and structures for fabrication of solar cells with laser ablation steps to form contact holes

    Science.gov (United States)

    Harley, Gabriel; Smith, David D; Dennis, Tim; Waldhauer, Ann; Kim, Taeseok; Cousins, Peter John

    2013-11-19

    Contact holes of solar cells are formed by laser ablation to accomodate various solar cell designs. Use of a laser to form the contact holes is facilitated by replacing films formed on the diffusion regions with a film that has substantially uniform thickness. Contact holes may be formed to deep diffusion regions to increase the laser ablation process margins. The laser configuration may be tailored to form contact holes through dielectric films of varying thickness.

  4. Social and environmental impact of the bioclimatic design; Impacto social y ambiental del diseno bioclimatico

    Energy Technology Data Exchange (ETDEWEB)

    Lopez P, J. Manuel A; Morrillon G, David; Rodriguez V, Luis [Instituto de Ingenieria de la UNAM, Mexico, D.F. (Mexico)

    2000-07-01

    This article is about two important scopes of the Bioclimatical Design (BD), the Social scope and the environmental scope. As an introduction, it is justified the importance of this topic through the association of the BD in the context of sustainability with our country's economic model. The analysis is done under the perspective of effects of the BD on social and environmental scopes. In social scope is used the Cost and Benefit Analysis according to social evaluation. In environmental scope, effects in water, air and ground are studied, but the measurement is done according to the emissions reduction of CO{sub 2} on atmosphere because of the earn on energy consumption. The results of the measurement of this effects are related with economical costs and benefits, which may show a general view about economical, social and environmental scopes. As conclusions, interest results are show and this is proposed to incorporate them in the economical politics. [Spanish] En este articulo se tocan dos aspectos importantes del Diseno Bioclimatico (DB), el Impacto Social y el Impacto Ambiental. En la introduccion se justifica la importancia del tema, asociando el DB en el contexto de la sustentabilidad, con el modelo economico que se ha imperado en nuestro pais. El estudio se realiza bajo la perspectiva de los impactos que el DB tiene en el aspecto social y en el ambiental. En lo social, se recurre a la metodologia del Analisis Costo-Beneficio para evaluacion Social, en lo ambiental, aunque se tocan los puntos de impacto en aire, agua y uso de suelo, la medicion del impacto se realiza con base en la disminucion de emisiones de CO{sub 2} a la atmosfera por el ahorro en el consumo de energia electrica. Los resultados de la medicion de impactos se cruzan con los costos y beneficios economicos, para presentar un panorama completo en cuanto a aspectos economicos, sociales y ambientales. En las conclusiones se rescatan los resultados de interes y se proponen las inserciones de

  5. An Open-Source Building System with Digitally Fabricated Components : A design- and production process that makes optimal use of the predicted next industrial revolution

    NARCIS (Netherlands)

    Stoutjesdijk, P.M.M.

    2013-01-01

    With digital fabrication, our hardware is starting to bear greater resemblance to software. This paper explores the potential of processes used in the development of open-source software for the field of Architecture. The developed design process is connected to a building system that provides new

  6. Development and evaluation of omeprazole pellets fabricated by sieving-spheronization and extrusion - spheronization process.

    Science.gov (United States)

    Karim, Sabiha; Baie, Saringat H; Hay, Yuen Kah; Bukhari, Nadeem Irfan

    2014-05-01

    Pelletized dosage forms can be prepared by different methods which, in general, are time consuming and labor intensive. The current study was carried out to investigate the feasibility of preparing the spherical pellets of omeprazole by sieving-spheronization. An optimized formulation was also prepared by extrusion-spheronization process to compare the physical parameters between these two methods. The omeprazole pellets were consisted of microcrystalline cellulose, polyvinylpyrrolidone K 30, sodium lauryl sulphate and polyethylene glycol 6000. The omeprazole delay release system was developed by coating the prepared pellets with aqueous dispersion of Kollicoat 30 DP. The moisture content, spheronization speed and residence time found to influence the final properties of omeprazole pellets prepared by extrusion-spheronization and sieving-spheronization. The Mann-Whitney test revealed that both methods produced closely similar characteristics of the pellets in terms of, friability (p=0.553), flowability (p=0.677), hardness (p=0.103) and density (bulk, p=0.514, tapped, p=0.149) except particle size distribution (p=0.004). The percent drug release from the coated formulation prepared by sieving-spheronization and extrusion spheronization was observed to be 84.12 ± 1.10% and 82.67 ± 0.96%, respectively. Dissolution profiles of both formulations were similar as indicated by values of f1 and f2, 1.52 and 89.38, respectively. The coated formulation prepared by sieving-spheronization and commercial reference product, Zimore ® also showed similar dissolution profiles (f1=1.22, f2=91.52). The pellets could be prepared using sieving-spheronization. The process is simple, easy, less time- and labor-consuming and economical as compared to extrusion-spheronization process.

  7. Synthesis and growth mechanisms of ZrC whiskers fabricated by a VLS process

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Dongju [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of). Nuclear Materials Development Division; Song, Sung Ho [Kongju National Univ., Chungnam (Korea, Republic of). Division of Advanced Materials Engineering

    2017-08-15

    The mechanisms of nano-sized ZrC whisker formation by a vapor-liquid-solid process (VLS) are investigated, which produces a very high purity, single crystal whisker. Rectangular ZrC whiskers with a cross-sectional diameter of 100-200 nm and lengths up to tens of microns are formed under the catalytic effect of nickel. The ZrC whiskers are characterized using scanning electron microscopy, transmission electron microscopy, and X-ray diffraction. ZrC whiskers can be used as a potential reinforcing and strengthening phase for ceramic composites.

  8. Monolithic DSSC/CIGS tandem solar cell fabricated by a solution process.

    Science.gov (United States)

    Moon, Sung Hwan; Park, Se Jin; Kim, Sang Hoon; Lee, Min Woo; Han, Jisu; Kim, Jin Young; Kim, Honggon; Hwang, Yun Jeong; Lee, Doh-Kwon; Min, Byoung Koun

    2015-03-11

    Tandem architecture between organic (dye-sensitized solar cell, DSSC) and inorganic (CuInGaSe2 thin film solar cell, CIGS) single-junction solar cells was constructed particularly based on a solution process. Arc-plasma deposition was employed for the Pt interfacial layer to minimize the damage to the layers of the CIGS bottom cell. Solar cell efficiency of 13% was achieved, which is significant progress from individual single-junction solar cells (e.g., 7.25 and 6.2% for DSSC and CIGS, respectively).

  9. Silicon solar cell process development, fabrication and analysis. Phase II. Annual report, 1 July 1979-30 June 1980

    Energy Technology Data Exchange (ETDEWEB)

    Yoo, H.I.; Iles, P.A.; Ho, F.F.; Leung, D.C.

    1980-01-01

    Solar cells were fabricated from EFG (RH) ribbons from multiple dies, silicon on ceramic (SOC), dendritic web, cast silicon by HEM, and semi-continuous CZ from both VARIAN and HAMCO. Baseline and improved solar cells were made from the sheets. Baseline solar cells processed in both Phase I and Phase II, involving cells from EFG, SOC, dendritic web, and HEM, indicated that no significant improvement in silicon sheet quality has been achieved in Phase II. Solar cells from semi-continuous CZ showed cell performance close to the conventional CZ control cells, although the cells from the semi-continuous CZ have shown wider performance range because of variation in crystalline perfection. Generally, process upgrading provided improvement in cell performance, the improvement depending on the process used and the quality of the sheet silicon. Study of the effect of grain size on solar cell performance suggested that the minimum grain size to make solar cells of 10% AMO efficiency is about 500 ..mu..m, which is expected to provide minimum module efficiency of 10% AMI. If other harmful impurities are added in the process of sheet growth, the minimum grain size must be increased. The BSF study showed that the higher the resistivity of the starting substrates, the greater the relative improvement in cell performance, probably because of greater shift in Fermi levels at the back L/H junction (pp+) and also because of the higher initial values of minority carrier diffusion length. This study also suggested that proper control of the back-surface field (BSF) process could minimize the junction shunting problems often introduced by the BSF processing.

  10. Hybrid deburring process assisted by a large pulsed electron beam (LPEB) for laser-fabricated patterned metal masks

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jisoo; Park, Hyung Wook, E-mail: hwpark@unist.ac.kr

    2015-12-01

    Highlights: • Patterned metal masks made of AISI 304 stainless steel were fabricated by fiber-laser. • Abrasive deburring alone, large pulsed electron beam (LPEB) deburring alone, and hybrid deburring process assisted by LPEB were performed. • A numerical heat transfer model for LPEB irradiation approximately predicted the melting depths and experimental studies revealed the limitation on eliminating burr size of LPEB irradiation alone. • The size of remaining burrs after the hybrid deburring process was reduced to7.2 μm. • The surface roughness (Ra) following the hybrid deburring process was reduced from 640 nm to 121 nm indicating a relatively uniform surface texture. - Abstract: The quality of pixels on displays and semiconductors is directly related to the surface quality of the patterned metal mask used. Burrs generated on the patterned metal mask can degrade the quality of pixels on microelectronic devices during the deposition process. In this study, experimental observations of abrasive deburring along with large pulsed electron beam (LPEB) irradiation were performed to evaluate the deburring effects on patterned metal masks. Numerical modeling of LPEB irradiation approximately predicted melting depths and the experimental studies revealed limitations in the size of burrs removed by LPEB irradiation. Thus a LPEB-assisted hybrid deburring process was developed to eliminate burrs of metal masks regardless of their size. The size of burrs remaining after the LPEB-assisted hybrid deburring process was reduced to approximately 7.2 μm which was much less than the results of abrasive deburring alone (38.01 μm). The burr size distribution was reduced by 85% and surface roughness (Ra) was decreased from 640 nm to 121 nm, indicating a uniform surface texture.

  11. Fabrication of Al5083/B4C surface composite by friction stir processing and its tribological characterization

    Directory of Open Access Journals (Sweden)

    Narayana Yuvaraj

    2015-10-01

    Full Text Available Improved surface properties with the retainment of bulk properties are necessary for a component for enhanced wear characteristics. Friction stir processing (FSP is used to produce such surface composites. Fabrication of 5083 aluminum alloy with reinforced layers of boron carbide (B4C through FSP was carried out. Micro and nano sized B4C particles were used as reinforcements. The friction processed surface composite layer was analyzed through optical and scanning electron microscopical studies. The number of passes and the size of reinforcement play a vital role in the development of surface composites by FSP. Mechanical properties of the friction stir processed surface composites were evaluated through micro hardness and universal tensile tests. The results were compared with the properties of the base metal. The role of reinforcement and number of passes on properties were also evaluated. Tribological performance of the surface composites is tested through pin on disk test. The surface composite layer resulted in three passes with nano particle reinforcement exhibited better properties in hardness, tensile behavior and wear resistance compared to the behavior of the base metal.

  12. Fabrication of Aligned Nanofibers by Manipulated Rotating Drum Method and Studying the Effective Parameters on Fibers Alignment by Image Processing

    Directory of Open Access Journals (Sweden)

    Zohreh Hadi

    2013-01-01

    Full Text Available Electrospinning is a known process to produce nanofibers through electrostatic forces. In a typical process, an electrical potential is applied between droplets of polymer solution or melt, held through a syringe needle and a grounded target. In general electrospinning fibers are collected on the grounded target as a random oriented web of nanofiber. Various research projects are attempted to obtain aligned electrospun fibers. This modified electrospinning method can be developed and used in a variety of nanofiber-based applications such as making of nanofibrous scaffolds for tissue engineering. In this study, an effective method has been developed to fabricate aligned nanofibers by manipulation of electrospinning system using two nozzles with opposite charges. Moreover, the effect of some parameters including take-up velocity, applied voltage and polymer solution concentration on alignment of produced nanofibers is investigated. The comparison of fibers alignment was carried out by programming and image processing in MATLAB. It is shown that take-up velocity and polymer solution concentration have significant effect on increasing the fibers alignment. Also, the alignment is increased with applied voltage at first and then, it is decreased. The analytical results and optical microscopic images are clear evidence of showing the maximum alignment of nanofibers obtained at 15% polymer solution concentration with take-up velocity of 600 rpm and 11 kV voltage.

  13. Antimicrobial Effectiveness of Cellulose based Fabrics treated with Silver Nitrate Solution using Plasma Processes

    Directory of Open Access Journals (Sweden)

    Jelena Peran

    2017-12-01

    Full Text Available In order to obtain antibacterial properties, the possibility of deposition of silver particles from silver nitrate (AgNO3 solutions by plasma deposition process using argon as a carrier gas (PDP-Ar was explored. Hexamethyldisiloxane and acrylic acid were used as precursors and were deposited by plasma enhanced-chemical vapor deposition (PE-CVD. The processes were carried out on lyocell and modal fbrics and antimicrobial efficacy was determined on E. coli and S. aureus using time kill assay method. The results of minimal inhibitory concentration (MIC show that higher antimicrobial efficacy on E. coli is exhibited by the solution of (AgNO3 in ethylene-glycol (0.066 μg/ml rather than in absolute ethanol (0.265 μg/ml. For S. aureus, minimal inhibitory concentrations of AgNO3 solutions in both absolute ethanol and ethylene-glycol as solvents are obtained at the same value (0.132 μg/ml. Overall, the best antibacterial eff ect for both modal and lyocell samples has been achieved against E. coli using treatments with precursors (AAC and HMDSO and Ag-NO3 in ethylene-glycol as solvent, with prolonged incubation time.

  14. Optimal condition for fabricating superhydrophobic Aluminum surfaces with controlled anodizing processes

    Science.gov (United States)

    Saffari, Hamid; Sohrabi, Beheshteh; Noori, Mohammad Reza; Bahrami, Hamid Reza Talesh

    2018-03-01

    A single step anodizing process is used to produce micro-nano structures on Aluminum (1050) substrates with sulfuric acid as electrolyte. Therefore, surface energy of the anodized layer is reduced using stearic acid modification. Undoubtedly, effects of different parameters including anodizing time, electrical current, and type and concentration of electrolyte on the final contact angle are systemically studied and optimized. Results show that anodizing current of 0.41 A, electrolyte (sulfuric acid) concentration of 15 wt.% and anodizing time of 90 min are optimal conditions which give contact angle as high as 159.2° and sliding angle lower than 5°. Moreover, the study reveals that adding oxalic acid to the sulfuric acid cannot enhance superhydrophobicity of the samples. Also, scanning electron microscopy images of samples show that irregular (bird's nest) structures present on the surface instead of high-ordered honeycomb structures expecting from normal anodizing process. Additionally, X-ray diffraction analysis of the samples shows that only amorphous structures present on the surface. The Brunauer-Emmett-Teller (BET) specific surface area of the anodized layer is 2.55 m2 g-1 in optimal condition. Ultimately, the surface keeps its hydrophobicity in air and deionized water (DIW) after one week and 12 weeks, respectively.

  15. Fabrication of TiO2/PU Superhydrophobic Film by Nanoparticle Assisted Cast Micromolding Process.

    Science.gov (United States)

    Li, Jie; Zheng, Jianyong; Zhang, Jing; Feng, Jie

    2016-06-01

    Lotus-like surfaces have attracted great attentions in recent years for their wide applications in water repellency, anti-fog and self-cleaning. This paper introduced a novel process, nanoparticle assisted cast micromolding, to create polymer film with superhydrophobic surface. Briefly, waterborne polyurethane (WPU) sol and nano TiO2/WPU sol were each cast onto the featured surfaces of the poly(dimethylsiloxane) (PDMS) stamps replicated from fresh lotus leaves. After being dried and peeled off from the stamps, PU and TiO2/WPU replica films were created respectively. To the former, only high hydrophobic property was observed with static water contact angle (WCA) at 142.5 degrees. While to the later, superhydrophobic property was obtained with WCA more than 150 degrees and slide angle less than 3 degrees. Scanning electron microscopy (SEM) imaging showed that the PU replica film only had the micro-papillas and the TiO2/PU replica film not only had micro papillas but also had a large number of nano structures distributed on and between the micro-papillas. Such nano and micro hierarchical structures were very similar with those on the natural lotus leaf surface, thus was the main reason for causing superhydrophobic property. Although an elastic PDMS stamp from lotus leaf was used in herein process, hard molds may also be used in theory. This study supplied an alternative technique for large scale production of polymeric films with superhydrophobic.

  16. Fabrication of amine-functionalized magnetite nanoparticles for water treatment processes

    International Nuclear Information System (INIS)

    Chan, Candace C. P.; Gallard, Hervé; Majewski, Peter

    2012-01-01

    Amine-functionalized magnetite nanoparticles are synthesized by a one pot water based process using N-[3-(trimethoxysilyl)propyl]diethylenetriamine (TRIS) as surfactant. The prepared functionalised nanoparticles are characterised by BET surface area measurements, X-ray diffraction, zeta potential measurement, and X-ray photoelectron spectrometry (XPS). The results clearly show the presence of TRIS on the surface of the nanoparticles. XPS analysis indicates the presence of very small amounts of maghemite on the surface of the magnetite nanoparticles. Water treatment test shows that the prepared nanoparticles are capable to remove natural organic matter (NOM) from natural water samples. The removal of NOM by the prepared particles is characterized by analysing the dissolved organic carbon (DOC) content and UV absorbance at 254 nm (UV 254 ) after the treatment of the water samples at various doses and treatment times.

  17. Simulation Analysis of a Fabrication Process of a Tannery: Case Study of a Latin American Company

    Directory of Open Access Journals (Sweden)

    Carolina Pirachicán-Mayorga

    2017-12-01

    Full Text Available A large number of real-life optimization problems in economics and business are complex and difficult to solve. Among the solutions techniques available in the Management Sciences, Discrete-Event computer Simulation (DES can be considered as one of the most preferred by practitioners. DES has been used as an analysis tool to evaluate new production system concepts, and has also been used in the operation and planning of manufacturing facilities. In this paper, we propose to apply DES for the analysis of a tannery manufacturing facility. The objective is to analyze the current performance of the production system in order to propose alternatives for improvement, as well as optimum parameters for production. Results obtained showed the advantages of using such a quantitative decision-aid technique by capturing most of the complexity characteristics of the production process.

  18. Effect of fabrication process on physical and mechanical properties of tungsten carbide - cobalt composite: A review

    Science.gov (United States)

    Mahaidin, Ahmad Aswad; Jaafar, Talib Ria; Selamat, Mohd Asri; Budin, Salina; Sulaiman, Zaim Syazwan; Hamid, Mohamad Hasnan Abdul

    2017-12-01

    WC-Co, which is also known as cemented carbide, is widely used in metal cutting industry and wear related application due to their excellent mechanical properties. Manufacturing industries are focusing on improving productivity and reducing operational cost with machining operation is considered as one of the factors. Thus, machining conditions are becoming more severe and required better cutting tool bit with improved mechanical properties to withstand high temperature operation. Numerous studies have been made over the generation for further improvement of cemented carbide properties to meet the constant increase in demand. However, the results of these studies vary due to different process parameters and manufacturing technology. This paper summarizes the studies to improve the properties of WC-Co composite using different consolidation (powder size, mixing method, formulation, etc) and sintering parameters (temperature, time, atmosphere, etc).

  19. Fabricating Super-hydrophobic Polydimethylsiloxane Surfaces by a Simple Filler-Dissolved Process

    Science.gov (United States)

    Lin, Yung-Tsan; Chou, Jung-Hua

    2010-12-01

    The self-cleaning effect of super-hydrophobic surfaces has attracted the attention of researchers. Typical ways of manufacturing super-hydrophobic surfaces include the use of either dedicated equipment or a complex chemical process. In this study, a simple innovative filler-dissolved method is developed using mainly powder salt and rinsing to form hydrophobic surfaces. This method can produce large super-hydrophobic surfaces with porous and micro rib surface structures. It can also be applied to curved surfaces, including flexible membranes. The contact angle of the manufactured artificial hydrophobic surface is about 160°. Furthermore, water droplets roll off the surface readily at a sliding angle of less than 5°, resembling the nonwetting lotus like effect.

  20. Unified planar process for fabricating heterojunction bipolar transistors and buried-heterostructure lasers utilizing impurity-induced disordering

    Energy Technology Data Exchange (ETDEWEB)

    Thornton, R.L.; Mosby, W.J.; Chung, H.F.

    1988-12-26

    We describe results on a novel geometry of heterojunction bipolar transistor that has been realized by impurity-induced disordering. This structure is fabricated by a method that is compatible with techniques for the fabrication of low threshold current buried-heterostructure lasers. We have demonstrated this compatibility by fabricating a hybrid laser/transistor structure that operates as a laser with a threshold current of 6 mA at room temperature, and as a transistor with a current gain of 5.

  1. Composite film fabricated on biomedical material with corona streamer plasma processing to mitigate bacterial adhesion

    Science.gov (United States)

    Alhamarneh, Ibrahim; Pedrow, Patrick; Eskhan, Asma; Abu-Lail, Nehal

    2011-10-01

    Composite films might control bacterial adhesion and concomitant biofouling that afflicts biomedical materials. Different size molecules of polyethylene glycol (PEG) with nominal molecular weights 600, 2000, and 20000 g/mol were used to synthesize composite films with plasma processing and dip-coating procedures on surgical-grade 316L stainless steel. Before dip-coating, the substrate was pre-coated with plasma-polymerized di(ethylene glycol) vinyl ether (pp-EO2V) in an atmospheric pressure corona streamer plasma reactor. The PEG dip-coating step followed immediately in the same chamber due to the finite lifetime of radicals associated with freshly deposited pp-EO2V. Morphology of the composite film was investigated with an ESEM. FTIR confirmed incorporation of pp-EO2V and PEG species into the composite film. More investigations on the composite film were conducted by XPS measurements. Adhesion of the composite film was evaluated with a standard peel-off test. Stability of the composite film in buffer solution was evaluated by AFM. AFM was also used to measure the film roughness and thickness. Polar and non-polar contact angle measurements were included.

  2. Inorganic metallodielectric materials fabricated using two single-step methods based on the Tollen's process.

    Science.gov (United States)

    Peterson, Molly S M; Bouwman, Jason; Chen, Aiqing; Deutsch, Miriam

    2007-02-01

    Two methods for preparing polycrystalline silver shells on colloidal silica spheres are reported. These do not include the use of organic ligands or metal seeding steps and are based on the Tollen's process for silvering glass. Reaction parameters such as temperature and reactant concentrations are adjusted to slow the reaction kinetics, which we find leads to preferential silver growth on the spheres. The resulting shells are polycrystalline and granular, showing highly uniform sphere coverage. Surface morphologies range from sparsely interconnected grains for shells approximately 20 nm thick, to complete (yet porous) shells of interconnected silver clusters which are up to approximately 140 nm in thickness. The extinction spectra of the core-shell materials are markedly different from those of smooth continuous shells, showing clear evidence that the granular shell geometry influences the plasmon resonance of the composite system. Spheres coated with shells 20-40 nm thick are also suitable for colloidal crystallization. Monolayers of self-assembled spheres with long-range ordering are demonstrated.

  3. Development of medical tube fabrication process from RVNRL: optimization and extrusion device at low temperature

    International Nuclear Information System (INIS)

    Collantes, Hugo David Chirinos

    1999-01-01

    The natural rubber latex was formulated, irradiation vulcanized and stabilized (GAMATEX) to make rubber goods for medical purpose. When the latex was vulcanized by gamma rays the effectiveness crosslinking of GAMATEX relationship between the concentration ratio of sensitizer system (x 1 =[n-BA]/[KOH]) and the vulcanization dose (x 2 ), showing high interaction grade. The RVNRL process was optimized for low vulcanization doses and high concentrations of n-BA. The resistance to radiolytic oxidation of rubber obtained from GAMATEX was attained when one antioxidants mixture (45% BANOX S + 55% TNPP) was added. This mixture exhibited synergetic effect. The latex showed pseudoplastic rheological behavior and the yield stress occurrence. The irreversible destabilization rate of latex was direct proportional to [n-BA] and indirect proportional to [KOH]. The post-irradiation effects or reversible destabilization of latex occurred because there is a residual concentration of [n-BA] that it was not reacted. The colloidal stability of GAMATEX improved with irradiation, showing showing the increase of thixotropic behavior and the tendency to Newtonian behavior flow besides the relationship between the viscosity index (k) and the pseudoplastic index (n). This fact allows the higher storage time of GAMATEX. The relative viscosity of latex was relationship between the temperature and the total dry rubber content according to the mathematical model: log ηrel = 0,18+1,09r w , where r w is the ratio (BS/100-BS). The radiation vulcanized latex coagulated at -10 deg C into the projected freezing system. (author)

  4. Fabrication of Elemental Copper by Intense Pulsed Light Processing of a Copper Nitrate Hydroxide Ink.

    Science.gov (United States)

    Draper, Gabriel L; Dharmadasa, Ruvini; Staats, Meghan E; Lavery, Brandon W; Druffel, Thad

    2015-08-05

    Printed electronics and renewable energy technologies have shown a growing demand for scalable copper and copper precursor inks. An alternative copper precursor ink of copper nitrate hydroxide, Cu2(OH)3NO3, was aqueously synthesized under ambient conditions with copper nitrate and potassium hydroxide reagents. Films were deposited by screen-printing and subsequently processed with intense pulsed light. The Cu2(OH)3NO3 quickly transformed in less than 100 s using 40 (2 ms, 12.8 J cm(-2)) pulses into CuO. At higher energy densities, the sintering improved the bulk film quality. The direct formation of Cu from the Cu2(OH)3NO3 requires a reducing agent; therefore, fructose and glucose were added to the inks. Rather than oxidizing, the thermal decomposition of the sugars led to a reducing environment and direct conversion of the films into elemental copper. The chemical and physical transformations were studied with XRD, SEM, FTIR and UV-vis.

  5. Toward practical all-solid-state lithium-ion batteries with high energy density and safety: Comparative study for electrodes fabricated by dry- and slurry-mixing processes

    Science.gov (United States)

    Nam, Young Jin; Oh, Dae Yang; Jung, Sung Hoo; Jung, Yoon Seok

    2018-01-01

    Owing to their potential for greater safety, higher energy density, and scalable fabrication, bulk-type all-solid-state lithium-ion batteries (ASLBs) employing deformable sulfide superionic conductors are considered highly promising for applications in battery electric vehicles. While fabrication of sheet-type electrodes is imperative from the practical point of view, reports on relevant research are scarce. This might be attributable to issues that complicate the slurry-based fabrication process and/or issues with ionic contacts and percolation. In this work, we systematically investigate the electrochemical performance of conventional dry-mixed electrodes and wet-slurry fabricated electrodes for ASLBs, by varying the different fractions of solid electrolytes and the mass loading. This information calls for a need to develop well-designed electrodes with better ionic contacts and to improve the ionic conductivity of solid electrolytes. As a scalable proof-of-concept to achieve better ionic contacts, a premixing process for active materials and solid electrolytes is demonstrated to significantly improve electrochemical performance. Pouch-type 80 × 60 mm2 all-solid-state LiNi0·6Co0·2Mn0·2O2/graphite full-cells fabricated by the slurry process show high cell-based energy density (184 W h kg-1 and 432 W h L-1). For the first time, their excellent safety is also demonstrated by simple tests (cutting with scissors and heating at 110 °C).

  6. Physical properties and microstructure study of 316L SS fabricated by metal injection moulding process

    Science.gov (United States)

    Dandang, Nur Aidah Nabihah; Harun, Wan Sharuzi Wan; Khalil, Nur Zalikha; Ismail, Muhammad Hussain; Ibrahim, Rosdi

    2017-12-01

    Metal injection moulding (MIM) has been practised to process alloy powders to become components with significant physical and mechanical properties. Dissimilar than other methods, MIM focuses on the production of high volume, a small, and complex shape of products. The performance of the compacts depends on the suitable sintering parameters that governs their strengths in the final phase which determines the excellent properties of the sintered compacts. Three different sintering temperatures were utilised; 1100, 1200, and 1300 °C with two different soaking times; 1 and 3 hours at 10 °C/min heating rate to study their effect on the physical properties and microstructure analysis of 316L SS alloy compacts. The shrinkage measurement, surface roughness, and density measurement had been conducted for physical properties study. Different sintering temperatures give an effect to the physical properties of the sintered compacts. The shrinkage measurement at 1300 °C and 3-hour sintering condition demonstrated the highest percentage reading which was 10.1 % compared to the lowest percentage reading of 6.4 % at 1100 °C and 1-hour sintering conditions. Whereas, the minimum percentage of density measurement can be found at sintering conditions of 1100 °C and 1-hour which is 83.9 % and the highest percentage is at 1300 °C and 3-hour sintering condition which is about 89.51 %. Therefore, it has been determined that there could be a significant relationship between sintering temperature and physical properties in which it can be found from the porosity of the compact based on the microstructure studies.

  7. A database of wavefront measurements for laser system modeling, optical component development and fabrication process qualification

    International Nuclear Information System (INIS)

    Wolfe, C.R.; Lawson, J.K.; Aikens, D.M.; English, R.E.

    1995-01-01

    In the second half of the 1990's, LLNL and others anticipate designing and beginning construction of the National Ignition Facility (NIF). The NIF will be capable of producing the worlds first laboratory scale fusion ignition and bum reaction by imploding a small target. The NIF will utilize approximately 192 simultaneous laser beams for this purpose. The laser will be capable of producing a shaped energy pulse of at least 1.8 million joules (MJ) with peak power of at least 500 trillion watts (TV). In total, the facility will require more than 7,000 large optical components. The performance of a high power laser of this kind can be seriously degraded by the presence of low amplitude, periodic modulations in the surface and transmitted wavefronts of the optics used. At high peak power, these phase modulations can convert into large intensity modulations by non-linear optical processes. This in turn can lead to loss in energy on target via many well known mechanisms. In some cases laser damage to the optics downstream of the source of the phase modulation can occur. The database described here contains wavefront phase maps of early prototype optical components for the NIF. It has only recently become possible to map the wavefront of these large aperture components with high spatial resolution. Modem large aperture static fringe and phase shifting interferometers equipped with large area solid state detectors have made this possible. In a series of measurements with these instruments, wide spatial bandwidth can be detected in the wavefront

  8. Fabrication and Characterization of ZnO Nano-Clips by the Polyol-Mediated Process.

    Science.gov (United States)

    Wang, Mei; Li, Ai-Dong; Kong, Ji-Zhou; Gong, You-Pin; Zhao, Chao; Tang, Yue-Feng; Wu, Di

    2018-02-09

    ZnO nano-clips with better monodispersion were prepared successfully using zinc acetate hydrate (Zn(OAc) 2 ·nH 2 O) as Zn source and ethylene glycol (EG) as solvent by a simple solution-based route-polyol process. The effect of solution concentration on the formation of ZnO nano-clips has been investigated deeply. We first prove that the 0.01 M Zn(OAc) 2 ·nH 2 O can react with EG without added water or alkaline, producing ZnO nano-clips with polycrystalline wurtzite structure at 170 °C. As-synthesized ZnO nano-clips contain a lot of aggregated nanocrystals (~ 5 to 15 nm) with high specific surface area of 88 m 2 /g. The shapes of ZnO nano-clips basically keep constant with improved crystallinity after annealing at 400-600 °C. The lower solution concentration and slight amount of H 2 O play a decisive role in ZnO nano-clip formation. When the solution concentration is ≤ 0.0125 M, the complexing and polymerization reactions between Zn(OAc) 2 ·nH 2 O and EG predominate, mainly elaborating ZnO nano-clips. When the solution concentration is ≥ 0.015 M, the alcoholysis and polycondensation reactions of Zn(OAc) 2 ·nH 2 O and EG become dominant, leading to ZnO particle formation with spherical and elliptical shapes. The possible growth mechanism based on a competition between complexing and alcoholysis of Zn(OAc) 2 ·nH 2 O and EG has been proposed.

  9. Microstructure and sliding wear characterization of Cu/TiB2 copper matrix composites fabricated via friction stir processing

    Directory of Open Access Journals (Sweden)

    I. Dinaharan

    2017-09-01

    Full Text Available The poor wear performance of copper is improved by reinforcing hard ceramic particles. The present work reports the fabrication of Cu/TiB2 (0, 6, 12, 18 vol.% copper matrix composites (CMCs using friction stir processing (FSP. TiB2 particles were initially packed together into a machined groove and were subjected to FSP under a constant set of process parameters. The microstructure was observed using optical, scanning and transmission electron microscopy. The wear behavior was examined using a pin-on-disc apparatus. The micrographs showed a homogeneous distribution of TiB2 particles without aggregation and segregation. The distribution of TiB2 particles was closely persistent across the stir zone. TiB2 particles were well bonded with the copper matrix without any interfacial reaction. Many TiB2 particles fractured during FSP. The grains in the composite were extensively refined because of dynamic recrystallization and pinning effect of TiB2 particles. The wear behavior under dry sliding condition was presented in detail.

  10. Fabrication and heat treatment of high strength Al-Cu-Mg alloy processed using selective laser melting

    Science.gov (United States)

    Zhang, Hu; Zhu, Haihong; Nie, Xiaojia; Qi, Ting; Hu, Zhiheng; Zeng, Xiaoyan

    2016-04-01

    The proposed paper illustrates the fabrication and heat treatment of high strength Al-Cu-Mg alloy produced by selective laser melting (SLM) process. Al-Cu-Mg alloy is one of the heat treatable aluminum alloys regarded as difficult to fusion weld. SLM is an additive manufacturing technique through which components are built by selectively melting powder layers with a focused laser beam. The process is characterized by short laser-powder interaction times and localized high heat input, which leads to steep thermal gradients, rapid solidification and fast cooling. In this research, 3D Al-Cu-Mg parts with relative high density of 99.8% are produced by SLM from gas atomized powders. Room temperature tensile tests reveal a remarkable mechanical behavior: the samples show yield and tensile strengths of about 276 MPa and 402 MPa, respectively, along with fracture strain of 6%. The effect of solution treatment on microstructure and related tensile properties is examined and the results demonstrate that the mechanical behavior of the SLMed Al-Cu-Mg samples can be greatly enhanced through proper heat treatment. After T4 solution treatment at 540°C, under the effect of precipitation strengthening, the tensile strength and the yield strength increase to 532 MPa and 338 MPa, respectively, and the elongation increases to 13%.

  11. Supportability of a High-Yield-Stress Slurry in a New Stereolithography-Based Ceramic Fabrication Process

    Science.gov (United States)

    He, Li; Song, Xuan

    2018-03-01

    In recent years, ceramic fabrication using stereolithography (SLA) has gained in popularity because of its high accuracy and density that can be achieved in the final part of production. One of the key challenges in ceramic SLA is that support structures are required for building overhanging features, whereas removing these support structures without damaging the components is difficult. In this research, a suspension-enclosing projection-stereolithography process is developed to overcome this challenge. This process uses a high-yield-stress ceramic slurry as the feedstock material and exploits the elastic force of the material to support overhanging features without the need for building additional support structures. Ceramic slurries with different solid loadings are studied to identify the rheological properties most suitable for supporting overhanging features. An analytical model of a double doctor-blade module is established to obtain uniform and thin recoating layers from a high-yield-stress slurry. Several test cases highlight the feasibility of using a high-yield-stress slurry to support overhanging features in SLA.

  12. Slit-surface electrospinning: a novel process developed for high-throughput fabrication of core-sheath fibers.

    Directory of Open Access Journals (Sweden)

    Xuri Yan

    Full Text Available In this work, we report on the development of slit-surface electrospinning--a process that co-localizes two solutions along a slit surface to spontaneously emit multiple core-sheath cone-jets at rates of up to 1 L/h. To the best of our knowledge, this is the first time that production of electrospun core-sheath fibers has been scaled to this magnitude. Fibers produced in this study were defect-free (i.e. non-beaded and core-sheath geometry was visually confirmed under scanning electron microscopy. The versatility of our system was demonstrated by fabrication of (1 fibers encapsulating a drug, (2 bicomponent fibers, (3 hollow fibers, and (4 fibers from a polymer that is not normally electrospinnable. Additionally, we demonstrate control of the process by modulating parameters such as flow rate, solution viscosity, and fixture design. The technological achievements demonstrated in this work significantly advance core-sheath electrospinning towards commercial and manufacturing viability.

  13. Slit-Surface Electrospinning: A Novel Process Developed for High-Throughput Fabrication of Core-Sheath Fibers

    Science.gov (United States)

    Yan, Xuri; Marini, John; Mulligan, Robert; Deleault, Abby; Sharma, Upma; Brenner, Michael P.; Rutledge, Gregory C.; Freyman, Toby; Pham, Quynh P.

    2015-01-01

    In this work, we report on the development of slit-surface electrospinning – a process that co-localizes two solutions along a slit surface to spontaneously emit multiple core-sheath cone-jets at rates of up to 1 L/h. To the best of our knowledge, this is the first time that production of electrospun core-sheath fibers has been scaled to this magnitude. Fibers produced in this study were defect-free (i.e. non-beaded) and core-sheath geometry was visually confirmed under scanning electron microscopy. The versatility of our system was demonstrated by fabrication of (1) fibers encapsulating a drug, (2) bicomponent fibers, (3) hollow fibers, and (4) fibers from a polymer that is not normally electrospinnable. Additionally, we demonstrate control of the process by modulating parameters such as flow rate, solution viscosity, and fixture design. The technological achievements demonstrated in this work significantly advance core-sheath electrospinning towards commercial and manufacturing viability. PMID:25938411

  14. Fabrication and processing of next-generation oxygen carrier materials for chemical looping combustion

    Energy Technology Data Exchange (ETDEWEB)

    Nadarajah, Arunan [Univ. of Toledo, OH (United States)

    2017-04-26

    Among numerous methods of controlling the global warming effect, Chemical Looping Combustion is known to be the most viable option currently. A key factor to a successful chemical looping process is the presence of highly effective oxygen carriers that enable fuel combustion by going through oxidation and reduction in the presence of air and fuel respectively. In this study, CaMnO3-δ was used as the base material and doped on the A-site (Sr or La) and B-site (Fe, Ti, Zn and Al) by 10 mol % of dopants. Solid state reaction followed by mechanical extrusion (optimized paste formula) was used as the preparation method A series of novel doped perovskite-type oxygen carrier particles (CaxLa (Or Sa)1-x Mn1-yByO3-δ (B-site = Fe, Ti, Al, or Zr)) were synthesized by the proposed extrusion formula. The produced samples were characterized with XRD, SEM, BET and TGA techniques. According to the results obtained from TGA analysis, the oxygen capacity of the samples ranged between 1.2 for CLMZ and 1.75 for CSMF. Reactivity and oxygen uncoupling behaviors of the prepared samples were also evaluated using a fluidized bed chemical looping reactor using methane as the fuel at four different temperatures (800, 850, 900, 950 °C). All of the oxygen carriers showed oxygen uncoupling behavior and they were able to capture and release oxygen. Mass-based conversion of the perovskites was calculated and temperature increase proved to increase the mass-based conversion rate in all of the samples under study. Gas yield was calculated at 950 °C as well, and results showed that CLMZ, CM and CSMF showed 100% gas yields and CLMF and CSMZ showed approximately 85% yield in fluidized bed reactor, which is a high and acceptable quantity. Based on extended reactor tests the modified calcium manganese perovskite structures (CSMF) can be a good candidate for future pilot tests.

  15. The climatic change and the new demands in dwelling design; El cambio climatico y las nuevas exigencias en el diseno de la vivienda

    Energy Technology Data Exchange (ETDEWEB)

    Tardan Waltz, Jenny [Asociacion de Empresas para el Ahorro de la Energia en la Edificacion, A.C. (Mexico)

    2007-10-15

    In Mexico, the culture of energy saving began more than one decade ago, but the benefits are not yet concrete. The Mexican society, requires new designs of dwellings adapted to its needs and in addition modifies the present systems of construction that do not include criteria of design for the thermal comfort, the energy saving and the sustainability. It is urgent to reconsider the urbanism of the cities, as well as the promotion of the concept of sustainable development in all the branches of human activity. The design of dwellings must significantly integrate the energy and environmental components to reduce to the power consumption and the CO{sub 2} emissions. [Spanish] En Mexico, la cultura de ahorro de energia se inicio hace mas de una decada, pero los beneficios aun no son palpables. La sociedad mexicana, requiere de nuevos disenos de viviendas que se adapten a sus necesidades y que ademas modifiquen los sistemas de construccion actuales que no incluyen criterios de diseno para el confort termico, el ahorro de energia y la sustentabilidad. Es urgente reconsiderar el urbanismo de las ciudades, asi como la promocion del concepto de desarrollo sustentable en todas las ramas de la actividad humana. El diseno de la vivienda debe integrar los componentes energeticos y medioambientales, para reducir significativamente el consumo de energia y las emisiones de CO{sub 2}.

  16. Hybrid 95: Software for the design of hybrid systems, Potrerillo of Santa Teresa; Hybrid 95: Software de diseno de sistemas hibridos, Potrerillo de Santa Teresa

    Energy Technology Data Exchange (ETDEWEB)

    Casaravilla, G.; Chaer, R. [Instituto de Ingenieria Electrica, Facultad de Ingenieria, Universidad de la Republica, Montevideo (Uruguay)

    1997-12-31

    This paper describes the software Hybrid 95 and how it is used for the design of hybrid systems. As an application example some of the design stages are looked over (determination of the wind resource, simulations for sizing generation/storage and topology) of the Potrerillo installation. Taking into account the site clear ecological connotations, during the design consideration is made of the visual impact that represents the possible wind-generator, therefore several locations and wind-generator heights are studied, even arriving to the wind-generation elimination. [Espanol] Este trabajo describe el software Hybrid 95 y como se utiliza a los efectos del diseno de sistemas hibridos. Como ejemplo de aplicacion se recorren algunas de las etapas del diseno (determinacion del recurso eolico, simulaciones para el dimensionado de generacion/acumulacion y topologia) de la instalacion de Potrerillo. Teniendo en cuenta las claras connotaciones ecologistas del lugar, durante el diseno se tiene presente el impacto visual que representa el eventual aerogenerador por lo que se estudian diversas ubicaciones y alturas de aerogenerador, llegandose incluso a estudiar la eliminacion de la generacion eolica.

  17. Evaluation of the impact of two flow field designs with bipolar plate flow on the performance of a PEM fuel cell; Evaluacion del impacto de dos disenos de campo de flujo de placa bipolar en el desempeno de una celda de combustible tipo PEM

    Energy Technology Data Exchange (ETDEWEB)

    Loyola-Morales, F.; Cano-Castillo, U. [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)]. E-mail: feloyola@yahoo.com.mx

    2009-09-15

    The flow field (FF) designs of bipolar plates play a fundamental role in the performance of a set of PEM fuel cells. The FF is directly related with diverse processes that occur inside the cells, such as: feeding and uniform distribution of reactant gases and the handling of water produced by the overall electrochemical reaction. Therefore, a FF design that promotes each one of those processes in an optimal manner is of utmost importance to attain the best performance of a set of fuel cells. The present work evaluated the impact of two different FF on the performance of a fuel cell. The FF designs evaluated were 4 serpentine and parallels (4SP) and 2 serpentine counter flow (SC). The stability tests for the operation of the cell applied to each of the flow fields were: flood tolerance, dehydration tolerance conditions and stoichiometry performance of 1.1, 1.3, 1.5 and 2.5. The 4SP design showed high performance stability during operation with a gradual process of flooding the system and operating at different stoichiometries. Only for the test with dehydration conditions was there a gradual decrease in its performance, of up to 27%. Compared to these results, the SC design showed a rapid fall of 45% in its performance when operating under gradual flooding of the system, a constant fall in its performance (also around 45%) with stoichiometries of 1.1, 1.3 and 1.5 due to accumulation of water, and only with a stoichiometry of 2.5 did it have highly stable performance as a result of good water handling. In the test of operations under dehydration conditions, the performance of the SC design dropped to 40% and remained at this value during the rest of the test. According to these results, the performance of the 4SP design was more stable than the SC design for all of the tests implemented. [Spanish] Los disenos de campo de flujo (CF) de las placas bipolares tienen un papel fundamental en el desempeno de un conjunto de celdas de combustible tipo PEM. Los CF tienen una

  18. The development of in-process inventory walk-through examination system in the process at borrowing inspection between LEU fuel fabrication plants

    International Nuclear Information System (INIS)

    Nakamura, Norihito; Namekawa, Masaru; Owada, Isao; Kikuchi, Masaru; Kodani, Yoshiki; Nozawa, Yukio

    2005-01-01

    Since the Nuclear Material Control Center (NMCC) was designed the safeguards inspection organization by Ministry of Education, Culture, Sports, Science and Technology (MEXT) in December 1999, the NMCC has been performing safeguards inspection for the Nuclear Facilities in Japan. The NMCC has carried out the safeguards inspections to LEU Fuel Fabrication Plants (FFPs) and the NMCC has improved the method of safeguards inspection as it has changed over to the integrated safeguards from the year of 2005. Concerning the Borrowing inspection between LEU FFPs, which is the precondition to change over to the integrated safeguards, it is needed to estimate the entire inventory in the facility within the limited time. Therefore, the NMCC has developed the system called IWES (In-process inventory Walk-through Examination System) to examine the inventory in process smoothly, quickly and correctly at borrowing inspection, check the entire inventory quantity and evaluate them. This report describes how IWES aiming at effective/efficient confirmation of in-process inventory has been developed and how it is applied to the borrowing inspection activities. (author)

  19. Fabrication of extremely thermal-stable GaN template on Mo substrate using double bonding and step annealing process

    Science.gov (United States)

    Qing, Wang; Yang, Liu; Yongjian, Sun; Yuzhen, Tong; Guoyi, Zhang

    2016-08-01

    A new layer transfer technique which comprised double bonding and a step annealing process was utilized to transfer the GaN epilayer from a sapphire substrate to a Mo substrate. Combined with the application of the thermal-stable bonding medium, the resulting two-inch-diameter GaN template showed extremely good stability under high temperature and low stress state. Moreover, no cracks and winkles were observed. The transferred GaN template was suitable for homogeneous epitaxial, thus could be used for the direct fabrication of vertical LED chips as well as power electron devices. It has been confirmed that the double bonding and step annealing technique together with the thermal-stable bonding layer could significantly improve the bonding strength and stress relief, finally enhancing the thermal stability of the transferred GaN template. Project supported by the Guangdong Innovative Research Team Program (No. 2009010044), the China Postdoctoral Science Foundation (No. 2014M562233), the National Natural Science Foundation of Guangdong, China (No. 2015A030312011), and the Opened Fund of the State Key Laboratory on Integrated Optoelectronics (No. IOSKL2014KF17).

  20. Microstructure and mechanical properties of Cu/SiC metal matrix composite fabricated via friction stir processing

    International Nuclear Information System (INIS)

    Akramifard, H.R.; Shamanian, M.; Sabbaghian, M.; Esmailzadeh, M.

    2014-01-01

    Highlights: • Designing a net hole was effective to achieve uniform distribution SiC particles and prevent agglomeration of them. • SZ has fine and equiaxed grains and distribution of SiC particles in the matrix is almost uniform. • No intermetallic compound was formed after FSP. • In comparison to pure Cu, Cu/SiC composite shows higher hardness and better wear behavior. - Abstract: In the present investigation, pure Cu sheets were reinforced with 25 μm SiC particles to fabricate a composite surface layer by friction stir processing (FSP). In order to improve distribution of reinforcing SiC particles, a net of holes were designed by drill on the surface of pure Cu sheet. For evaluation of microstructure, Optical Microscope (OM) and Scanning Electron Microscope (SEM) were used. Microstructural observation confirmed fine and equiaxed grains in the stir zone (SZ) and showed that SiC particles act as heterogeneous nucleation sites in the dynamic recrystallization of Cu grains. Moreover, agglomeration of particles was not observed and fine particles had a good distribution in SZ. In the SEM micrographs, porosities were detected as microstructure defects. Microhardness measurements showed that surface hardness was two times as high as that of substrate. The rotational wear tests demonstrated that use of SiC particles enhanced wear resistance and increased average friction coefficient of pure Cu. No intermetallic compound was found in Cu/SiC composite as revealed by XRD analysis

  1. Fabrication and evaluation of a microspring contact array using a reel-to-reel continuous fiber process

    Science.gov (United States)

    Khumpuang, S.; Ohtomo, A.; Miyake, K.; Itoh, T.

    2011-10-01

    In this work a novel patterning technique for fabrication of a conductive microspring array as an electrical contact structure directly on fiber substrate is introduced. Using low-temperature compression from the nanoimprinting technique to generate a gradient depth on the desired pattern, PEDOT: PSS film, the hair-like structures are released as bimorph microspring cantilevers. The microspring is in the form of a stress-engineered cantilever arranged in rows. The microspring contact array is employed in composing the electrical circuit through a large area of woven textile, and functions as the electrical contact between weft ribbon and warp ribbon. The spring itself has a contact resistance of 480 Ω to the plain PEDOT:PSS-coated ribbon, which shows a promising electrical transfer ability within the limitations of materials employed for reel-to-reel continuous processes. The microspring contact structures enhanced the durability, flexibility and stability of electrical contact in the woven textile better than those of the ribbons without the microspring. The contact experiment was repeated over 500 times, losing only 20 Ω of the resistance. Furthermore, to realize the spring structure, CYTOP is used as the releasing layer due to its low adhesive force to the fiber substrate. Moreover the first result of patternable CYTOP using nano-imprinting lithography is included.

  2. Effect of sintering temperature on physical properties & hardness of CoCrMo alloys fabricated by metal injection moulding process

    Science.gov (United States)

    Ridhwan Abdullah, Ahmad; Aidah Nabihah Dandang, Nur; Zalikha Khalil, Nur; Harun, Wan Sharuzi Wan

    2017-10-01

    Metal Injection Moulding (MIM) process is one of the Powder Metallurgy manufacturing techniques utilised to produce Cobalt Chromium Molybdenum (CoCrMo) compacts. The objective of this study is to determine physical properties and hardness of CoCrMo alloy compact sintered at three different sintering temperature at the similar soaking time. At the beginning, sample were fabricated by using Injection Moulding machine. Cobalt Chrome Molybdenum (CoCrMo) metal powder was selected for this study. A morphological study was conducted using optical microscope (OM) and micro-Vickers hardness testing. From the result obtained, it shows upward trend either on the hardness or physical properties of the samples. CoCrMo sintered compact become harder and volume of pores on surface become less due to the increase on sintering temperature. However, effect of increasing sintering temperature shows significant shrinkage of the sample, beginning losses in dimensional accuracy. It is discovered that a little change in sintering temperature gives significant impact on the microstructure, physical, mechanical of the alloy.

  3. Photocatalytic evaluation of self-assembled porous network structure of ferric oxide film fabricated by dry deposition process

    Energy Technology Data Exchange (ETDEWEB)

    Park, Yunchan; Kim, Hyungsub; Lee, Geon-Yong; Pawar, Rajendra C.; Lee, Jai-Sung; Lee, Caroline Sunyong, E-mail: sunyonglee@hanyang.ac.kr

    2016-09-15

    Ferric oxide powder in the alpha phase (α-Fe{sub 2}O{sub 3}) was deposited on an aluminum oxide (Al{sub 2}O{sub 3}) substrate by a nanoparticle deposition system using the dry deposition method. X-ray diffraction (XRD) images confirmed that the phase of the deposited α-Fe{sub 2}O{sub 3} did not change. The deposited α-Fe{sub 2}O{sub 3} was characterized in terms of its microstructure using scanning electron microscopy (SEM). A porous network microstructure formed when small agglomerates of Fe{sub 2}O{sub 3} (SAF) were deposited. The deposition and formation mechanism of the microstructure were investigated using SEM and three-dimensional (3D) profile analysis. First, a dense coating layer formed when the film was thinner than the particle size. After that, as the film thickness increased to over 5 μm, the porous network structure formed by excavating the surface of the coating layer as it was bombarded by particles. Rhodamine B (RhB) was degraded after 6 h of exposure to the Fe{sub 2}O{sub 3} coating layer with SAF, which has good photocatalytic activity and a high porous network structure. The kinetic rate constants of the SAF and large agglomerates of Fe{sub 2}O{sub 3} (LAF) were calculated to be 0.197(h{sup −1}) and 0.128(h{sup −1}), respectively, based on the absorbance results. Using linear sweep voltammetry, we confirmed that the photoelectric effect occurred in the coating layer by measuring the resulting current under illuminated and dark conditions. - Graphical abstract: Self-assembled porous photocatalytic film fabricated by dry deposition method for water purification. - Highlights: • Different sizes of Fe{sub 2}O{sub 3} agglomerates were used to form porous network structure. • Fe{sub 2}O{sub 3} agglomerate particles were deposited using solvent-free process. • Self-assembled porous network microstructure formed better with small agglomerates of Fe{sub 2}O{sub 3}. • Fabricated porous network structure showed its potential to be used

  4. SAMBA RECEPTION DESK: COMPROMISING AESTHETICS, FABRICATION AND STRUCTURAL PERFORMANCE WITH THE USE OF VIRTUAL AND PHYSICAL MODELS IN THE DESIGN PROCESS

    Directory of Open Access Journals (Sweden)

    Wilson Barbosa Neto

    2014-12-01

    Full Text Available The present paper describes an integrative design experiment in which different types of models were used in order to achieve a design that compromises aesthetics, lightness, fabrication, assembly and structural performance. It shows how an integrative aproach, through the use of both virtual and physical models, can provide valuable feedback in different phases of the design and fabrication process. It was possible to conclude that the design method used allowed solving many problems and had a significant impact in the resulting object.

  5. Fabrication of Al5083 surface composites reinforced by CNTs and cerium oxide nano particles via friction stir processing

    Energy Technology Data Exchange (ETDEWEB)

    Hosseini, S.A. [Department of Materials Science and Engineering, Faculty of Engineering, Shahid Chamran University of Ahvaz (Iran, Islamic Republic of); Ranjbar, Khalil, E-mail: k_ranjbar@scu.ac.ir [Department of Materials Science and Engineering, Faculty of Engineering, Shahid Chamran University of Ahvaz (Iran, Islamic Republic of); Dehmolaei, R. [Department of Materials Science and Engineering, Faculty of Engineering, Shahid Chamran University of Ahvaz (Iran, Islamic Republic of); Amirani, A.R. [12th Ghaem Street, Bld. Hashemzadeh, Shahrak Golestan, Tehran (Iran, Islamic Republic of)

    2015-02-15

    Highlights: • Using friction stir processing, an effect of CNTs and CeO{sub 2} reinforcements on mechanical and corrosion properties of Al5083 alloy is reported. • The strength of Al5083 was increased by 42%, its matrix grain size reduced five times, and hardness was doubled by the incorporation of CNTs-CeO{sub 2} mixture in the volume ratio of 75-25 respectively. • Unlike the CNTs, incorporation of nanosized CeO{sub 2} particles resulted in remarkable increase in pitting resistance of the alloy. - Abstract: In the present investigation, friction stir processing (FSP) was utilized to incorporate Multi Walled Carbon Nano Tubes (MWCNT) and nanosized cerium oxide particles into the matrix of Al5083 alloy to form surface reinforced composites. The effect of these nanosized reinforcements either separately or in the combined form, on microstructural modification, mechanical properties and corrosion resistance of FSPed Al5083 surface composites was studied. A threaded cylindrical hardened steel tool was used with the rotation speeds of 600 and 800 rpm and travel speeds of 35 and 45 mm/min and a tilt angle of 5°. Mechanical properties and corrosion resistance of FSPed samples were evaluated and compared with the base alloy. The maximum tensile strength and hardness value were achieved for the hybrid composite containing a mixture of CNTs and cerium oxide in the volume ratio of 75-25, respectively, whereas a significant increase in pitting resistance of the base alloy was obtained when cerium oxide alone was incorporated. The corrosion behavior of the samples was investigated by potentiodynamic polarization tests and assessed in term of pitting potential and passivation range. Microstructural analysis carried out by using optical and electron microscopes showed that reinforcements are well dispersed inside the nugget zone (NZ), and remarkable grain refinement is gained. The study was aimed to fabricate surface composites with improved mechanical properties and

  6. Characterization of Aluminum-Based-Surface Matrix Composites with Iron and Iron Oxide Fabricated by Friction Stir Processing

    Science.gov (United States)

    Mahmoud, Essam R. I.; Tash, Mahmoud M.

    2016-01-01

    Surface composite layers were successfully fabricated on an A 1050-H24 aluminum plate by dispersed iron (Fe) and magnetite (Fe3O4) particles through friction stir processing (FSP). Fe and Fe3O4 powders were packed into a groove of 3 mm in width and 1.5 mm in depth, cut on the aluminum plate, and covered with an aluminum sheet that was 2-mm thick. A friction stir processing (FSP) tool of square probe shape, rotated at a rate of 1000–2000 rpm, was plunged into the plate through the cover sheet and the groove, and moved along the groove at a travelling speed of 1.66 mm/s. Double and triple passes were applied. As a result, it is found that the Fe particles were homogenously distributed in the whole nugget zone at a rotation speed of 1000 rpm after triple FSP passes. Limited interfacial reactions occurred between the Fe particles and the aluminum matrix. On the other hand, the lower rotation speed (1000 rpm) was not enough to form a sound nugget when the dispersed particles were changed to the larger Fe3O4. The Fe3O4 particles were dispersed homogenously in a sound nugget zone when the rotation speed was increased to 1500 rpm. No reaction products could be detected between the Fe3O4 particles and the aluminum matrix. The saturation magnetization (Ms) of the Fe-dispersed nugget zone was higher than that of the Fe3O4-dispersed nugget zone. Moreover, there were good agreement between the obtained saturation magnetization values relative to that of pure Fe and Fe3O4 materials and the volume content of the dispersed particles in the nugget zone. PMID:28773629

  7. Teflon/SiO₂ Bilayer Passivation for Improving the Electrical Reliability of Oxide TFTs Fabricated Using a New Two-Photomask Self-Alignment Process.

    Science.gov (United States)

    Fan, Ching-Lin; Shang, Ming-Chi; Li, Bo-Jyun; Lin, Yu-Zuo; Wang, Shea-Jue; Lee, Win-Der; Hung, Bohr-Ran

    2015-04-13

    This study proposes a two-photomask process for fabricating amorphous indium-gallium-zinc oxide (a-IGZO) thin-film transistors (TFTs) that exhibit a self-aligned structure. The fabricated TFTs, which lack etching-stop (ES) layers, have undamaged a-IGZO active layers that facilitate superior performance. In addition, we demonstrate a bilayer passivation method that uses a polytetrafluoroethylene (Teflon) and SiO₂ combination layer for improving the electrical reliability of the fabricated TFTs. Teflon was deposited as a buffer layer through thermal evaporation. The Teflon layer exhibited favorable compatibility with the underlying IGZO channel layer and effectively protected the a-IGZO TFTs from plasma damage during SiO₂ deposition, resulting in a negligible initial performance drop in the a-IGZO TFTs. Compared with passivation-free a-IGZO TFTs, passivated TFTs exhibited superior stability even after 168 h of aging under ambient air at 95% relative humidity.

  8. Electrohydrodynamic jet process for pore-structure-controlled 3D fibrous architecture as a tissue regenerative material: fabrication and cellular activities.

    Science.gov (United States)

    Kim, Min Seong; Kim, GeunHyung

    2014-07-22

    In this study, we propose a new scaffold fabrication method, "direct electro-hydrodynamic jet process," using the initial jet of an electrospinning process and ethanol media as a target. The fabricated three-dimensional (3D) fibrous structure was configured with multilayered microsized struts consisting of randomly entangled micro/nanofibrous architecture, similar to that of native extracellular matrixes. The fabrication of the structure was highly dependent on various processing parameters, such as the surface tension of the target media, and the flow rate and weight fraction of the polymer solution. As a tissue regenerative material, the 3D fibrous scaffold was cultured with preosteoblasts to observe the initial cellular activities in comparison with a solid-freeform fabricated 3D scaffold sharing a similar structural geometry. The cell-culture results showed that the newly developed scaffold provided outstanding microcellular environmental conditions to the seeded cells (about 3.5-fold better initial cell attachment and 2.1-fold better cell proliferation).

  9. Control of Y-211 content in bulk YBCO superconductors fabricated by a buffer-aided, top seeded infiltration and growth melt process

    International Nuclear Information System (INIS)

    Namburi, Devendra K; Shi, Yunhua; Palmer, Kysen G; Dennis, Anthony R; Durrell, John H; Cardwell, David A

    2016-01-01

    Bulk (RE)–Ba–Cu–O ((RE)BCO, where RE stands for rare-earth), single grain superconductors can trap magnetic fields of several tesla at low temperatures and therefore can function potentially as high field magnets. Although top seeded melt growth (TSMG) is an established process for fabricating relatively high quality single grains of (RE)BCO for high field applications, this technique suffers from inherent problems such as sample shrinkage, a large intrinsic porosity and the presence of (RE) 2 BaCuO 5 (RE-211)-free regions in the single grain microstructure. Seeded infiltration and growth (SIG), therefore, has emerged as a practical alternative to TSMG that overcomes many of these problems. Until now, however, the superconducting properties of bulk materials processed by SIG have been inferior to those fabricated using the TSMG technique. In this study, we identify that the inferior properties of SIG processed bulk superconductors are related to the presence of a relatively large Y-211 content (∼41.8%) in the single grain microstructure. Controlling the RE-211 content in SIG bulk samples is particularly challenging because it is difficult to regulate the entry of the liquid phase into the solid RE-211 preform during the infiltration process. In an attempt to solve this issue, we have investigated the effect of careful control of both the infiltration temperature and the quantity of liquid phase powder present in the sample preforms prior to processing. We conclude that careful control of the infiltration temperature is the most promising of these two process variables. Using this knowledge, we have fabricated successfully a YBCO bulk single grain using the SIG process of diameter 25 mm that exhibits a trapped field of 0.69 T at 77 K, which is the largest value reported to date for a sample fabricated by the SIG technique. (paper)

  10. Fabrication and characterization of silver/titanium dioxide composite nanoparticles in ethylene glycol with alkaline solution through sonochemical process.

    Science.gov (United States)

    Jhuang, Ya-Yi; Cheng, Wen-Tung

    2016-01-01

    This paper aims to study fabrication and characterization of silver/titanium oxide composite nanoparticle through sonochemical process in the presence of ethylene glycol with alkaline solution. By using ultrasonic irradiation of a mixture of silver nitrate, the dispersed TiO2 nanoparticle in ethylene glycol associated with aqueous solution of sodium oxide yields Ag/TiO2 composite nanoparticle with shell/core-type geometry. The powder X-ray diffraction (XRD) of the Ag/TiO2 composites showed additional diffraction peaks corresponding to the face-centered cubic (fcc) structure of silver crystallization phase, apart from the signals from the cores of TiO2. Transmission electron microscopy (TEM) images of Ag/TiO2 composites, which average particle size is roughly 80 nm, reveal that the titanium oxide coated by Ag nanoparticle with a grain size of about 2-5 nm. Additionally, the formation of silver nanoparticles on TiO2 was monitored by ultraviolet visible light spectrophotometer (UV-Vis). As measured the optical absorption spectra of as-synthesized Ag nanoparticle varying with time, the mechanism of surface formatting silver shell on the cores of TiO2 could be explored by autocatalytic reaction; the conversion of Ag particle from silver ion is 98% for the reaction time of 1000 s; and the activity energy of synthesizing Ag nanoparticles on TiO2 is 40 kJ/mol at temperature ranging from 5 to 25°C. Hopefully, this preliminary investigation could be used for mass production of composite nanoparticles assisted by ultrasonic chemistry in the future. Copyright © 2015 Elsevier B.V. All rights reserved.

  11. Vanadium Dioxide and Vanadium Sesquioxide Thin Films Fabricated on (0001) or (1010)Al2O3 by Reactive RF-Magnetron Sputter Deposition and Subsequent Annealing Processes

    Science.gov (United States)

    Yun, Sun Jin; Lim, Jung Wook; Noh, Jong-Su; Kim, Bong-Jun; Kim, Hyun-Tak

    2009-04-01

    Vanadium dioxide (VO2) and vanadium sesquioxide (V2O3) thin films showing an abrupt metal-insulator transition near their typical critical temperature (TC) were successfully fabricated by reactive RF magnetron sputter deposition and subsequent annealing processes. The annealing processes for preparing VO2 and V2O3 films were carried out in 30 mTorr O2 ambient and at a very low pressure (2 ×10-6 Torr), respectively. V2O3 films could be fabricated by the one-step annealing of as-deposited VOx films in contrast to the V2O3 fabrication by the two-step annealing of sol-gel V2O5 films. The annealing temperature for preparing V2O3 films (≥550 °C) was much lower than those reported in earlier works. The dependence of TC on the surface orientation of a single crystalline Al2O3 substrate was also shown for VO2 and V2O3 films. The films fabricated on (1010)-plane Al2O3 substrate showed superior characteristics to those on (0001)-Al2O3.

  12. An Experimental Study on Fabricating an Inverted Mesa-Type Quartz Crystal Resonator Using a Cheap Wet Etching Process

    Directory of Open Access Journals (Sweden)

    Xuefeng Li

    2013-09-01

    Full Text Available In this study, a miniaturized high fundamental frequency quartz crystal microbalance (QCM is fabricated for sensor applications using a wet etching technique. The vibration area is reduced in the fabrication of the high frequency QCM with an inverted mesa structure. To reduce the complexity of the side wall profile that results from anisotropic quartz etching, a rectangular vibration area is used instead of the conventional circular structure. QCMs with high Q values exceeding 25,000 at 47 MHz, 27,000 at 60 MHz, 24,000 at 73 MHz and 25,000 at 84 MHz are fabricated on 4 × 4 mm2 chips with small vibration areas of 1.2 × 1.4 mm2. A PMMA-based flow cell is designed and manufactured to characterize the behavior of the fabricated QCM chip in a liquid. Q values as high as 1,006 at 47 MHz, 904 at 62 MHz, 867 at 71 MHz and 747 at 84 MHz are obtained when one side of the chip is exposed to pure water. These results show that fabricated QCM chips can be used for bio- and chemical sensor applications in liquids.

  13. Fabrication Facilities

    Data.gov (United States)

    Federal Laboratory Consortium — The Fabrication Facilities are a direct result of years of testing support. Through years of experience, the three fabrication facilities (Fort Hood, Fort Lewis, and...

  14. Fused deposition of ceramics: A comprehensive experimental, analytical and computational study of material behavior, fabrication process and equipment design

    Science.gov (United States)

    Bellini, Anna

    Customer-driven product customization and continued demand for cost and time savings have generated a renewed interest in agile manufacturing based on improvements on Rapid Prototyping (RP) technologies. The advantages of RP technologies are: (1) ability to shorten the product design and development time, (2) suitability for automation and decrease in the level of human intervention, (3) ability to build many geometrically complex shapes. A shift from "prototyping" to "manufacturing" necessitates the following improvements: (1) Flexibility in choice of materials; (2) Part integrity and built-in characteristics to meet performance requirements; (3) Dimensional stability and tolerances; (4) Improved surface finish. A project funded by ONR has been undertaken to develop an agile manufacturing technology for fabrication of ceramic and multi-component parts to meet various needs of the Navy, such as transducers, etc. The project is based on adaptation of a layered manufacturing concept since the program required that the new technology be developed based on a commercially available RP technology. Among various RP technologies available today, Fused Deposition Modeling (FDM) has been identified as the focus of this research because of its potential versatility in the choice of materials and deposition configuration. This innovative approach allows for designing and implementing highly complex internal architectures into parts through deposition of different materials in a variety of configurations in such a way that the finished product exhibit characteristics to meet the performance requirements. This implies that, in principle, one can tailor-make the assemble of materials and structures as per specifications of an optimum design. The program objectives can be achieved only through accurate process modeling and modeling of material behavior. Oftentimes, process modeling is based on some type of computational approach where as modeling of material behavior is based on

  15. Dimensional accuracy of internal cooling channel made by selective laser melting (SLM And direct metal laser sintering (DMLS processes in fabrication of internally cooled cutting tools

    Directory of Open Access Journals (Sweden)

    Ghani S. A. C.

    2017-01-01

    Full Text Available Selective laser melting(SLM and direct metal laser sintering(DMLS are preferred additive manufacturing processes in producing complex physical products directly from CAD computer data, nowadays. The advancement of additive manufacturing promotes the design of internally cooled cutting tool for effectively used in removing generated heat in metal machining. Despite the utilisation of SLM and DMLS in a fabrication of internally cooled cutting tool, the level of accuracy of the parts produced remains uncertain. This paper aims at comparing the dimensional accuracy of SLM and DMLS in machining internally cooled cutting tool with a special focus on geometrical dimensions such as hole diameter. The surface roughness produced by the two processes are measured with contact perthometer. To achieve the objectives, geometrical dimensions of identical tool holders for internally cooled cutting tools fabricated by SLM and DMLS have been determined by using digital vernier calliper and various magnification of a portable microscope. In the current study, comparing internally cooled cutting tools made of SLM and DMLS showed that generally the higher degree of accuracy could be obtained with DMLS process. However, the observed differences in surface roughness between SLM and DMLS in this study were not significant. The most obvious finding to emerge from this study is that the additive manufacturing processes selected for fabricating the tool holders for internally cooled cutting tool in this research are capable of producing the desired internal channel shape of internally cooled cutting tool.

  16. Low temperature processing of single domain YBa 2Cu 3O y thick films from Y 2O 3 fabrics on Ag-Pd alloy substrates

    Science.gov (United States)

    Reddy, E. S.; Goodilin, E. A.; Tarka, M.; Zeisberger, M.; Schmitz, G. J.

    2002-08-01

    Single domain YBa 2Cu 3O y (Y123) thick films (∼100 μm) were fabricated on untextured Ag12 wt.%Pd alloy substrates from Y 2O 3 cloths by an infiltration and growth process. The process involves the infiltration of Y 2O 3 cloths placed on metallic substrates by barium cuprates and copper oxide liquids at 970 °C. The infiltrated Y 2O 3 cloth is subsequently transformed into single domain Y123 during a slow cooling schedule in the presence of a c-axis oriented Nd123 seed crystal placed at the top center of the fabric. The solidification window for single domain growth is lowered to 970-950 °C using liquid phases containing up 10 wt.% Ag and small amounts of BaF 2.

  17. Design of a hydraulic microturbine type Michell-Banki; Diseno de una microturbina hidraulica tipo Michell-Banki

    Energy Technology Data Exchange (ETDEWEB)

    Lopez Luiz, Norberto; Rodriguez Bautista, Jose; Verduzco Figueroa, Hilario; Gudino Lau, Jorge; Galindo Granados, Miguel angel [Universidad de Colima, Facultad de Ingenieria Electromecanica, Manzanillo, Colima (Mexico)]. E-mail: norberto_lopez@ucol.mx

    2010-11-15

    The aim of this paper is to present the design of a hydraulic microturbine (MTH), which may be installed in areas where supplies are not available for electric power transmission lines, but possessing hydroelectric. MTH's role is to convert hydraulic energy into mechanical work, is coupled to an electric generator, whose function is to convert the mechanical energy into electrical energy. The turbine generator set will produce more electric power the greater the hydroelectric of the area. In southern Mexico, we have great hydroelectric potential, as the case of the states of Veracruz, Chiapas and Oaxaca, which have small causes of rivers where the MTH could be installed and put into operation. [Spanish] El objetivo de este articulo es presentar el diseno de una microturbina hidraulica (MTH), la cual podra ser instalada en zonas donde no se cuente con suministro de energia electrica por medio de lineas de transmision, pero que posean aprovechamientos hidroelectricos. La funcion de la MTH es convertir la energia hidraulica en trabajo mecanico, estara acoplada a un generador electrico, cuya funcion es convertir dicha energia mecanica en energia electrica. El conjunto turbina generador producira mas potencia electrica mientras mayor sea el aprovechamiento hidroelectrico de la zona. En el sur de Mexico contamos con un gran potencial hidroelectrico, como el caso de los estados de Veracruz, Chiapas y Oaxaca, que cuentan con pequenos causes de rios donde las MTH podrian ser instaladas y puestas en operacion.

  18. Process development for fabrication of Ag-15% In-5% Cd alloys and rods for the control rods of IPEN critical unit

    International Nuclear Information System (INIS)

    Figueredo, A.M. de.

    1985-12-01

    The development of two process at the Nuclear and Energetic Research Institute (IPEN-Brazil) are described. - the production of Ag-15% In-5%. Cd alloys with nuclear grade. The fabrication of rods from Ag-15% In-5% Cd alloy for use at the critical unit. The methods for quality control of alloy and rod are presented, and main problems are identified. (C.G.C.)

  19. Comparison of microstructure and mechanical properties of A356 aluminum alloy/Al2O3 composites fabricated by stir and compo-casting processes

    International Nuclear Information System (INIS)

    Sajjadi, S.A.; Ezatpour, H.R.; Torabi Parizi, M.

    2012-01-01

    Highlights: → Nano and micro-composites (A356/Al 2 O 3 ) were fabricated by stir-casting and compo-casting. → Uniform distribution, grain refinement and low porosity in the composites were attained. → Addition of alumina led to the improvement in yield, ultimate tensile and compression strength. → Nano-alumina particles and compo-casting process obtained the best mechanical properties. -- Abstract: Metal-matrix composites (MMCs), as light and strong materials, are very attractive for application in different industries. In the present work, nano and micro-composites (A356/Al 2 O 3 ) with different weight percent of particles were fabricated by two melt techniques such as stir-casting and compo-casting. Microstructural characterization was investigated by optical (OP) and scanning electron microscopy (SEM). Tensile, hardness and compression tests were carried out in order to identify mechanical properties of the composites. The results of microstructural study revealed uniform distribution, grain refinement and low porosity in micro and nano-composite specimens. The mechanical results showed that the addition of alumina (micro and nano) led to the improvement in yield strength, ultimate tensile strength, compression strength and hardness. It was indicated that type of fabrication process and particle size were the effective factors influencing on the mechanical properties. Decreasing alumina particle size and using compo-casting process obtained the best mechanical properties.

  20. Design optimization of the Laguna Verde nuclear power station fuel recharge; Optimacion del diseno de recargas de combustible para la Central Laguna Verde

    Energy Technology Data Exchange (ETDEWEB)

    Cortes Campos, Carlos Cristobal [Instituto de Investigaciones Electricas, Cuernavaca (Mexico); Montes Tadeo, Jose Luis [Instituto Nacional de Investigaciones Nucleares (ININ), Salazar (Mexico)

    1991-12-31

    It is described, in general terms, the procedure that is followed to accomplish the optimization of the recharge design, and an example is shown where this procedure was applied for the analysis of the type BWR reactor of Unit No. 1 of the Laguna Verde Nuclear Power Station. [Espanol] Se describe en terminos generales el procedimiento que se sigue para realizar la optimacion del diseno de recargas, y se muestra un ejemplo en el que se utilizo dicho procedimiento para el analisis del reactor tipo BWR de la unidad 1, de la Central Laguna Verde (CLV).

  1. Fabricating nuclear components

    International Nuclear Information System (INIS)

    Anon.

    1977-01-01

    Activities of the Nuclear Engineering Division of Vickers Ltd., particularly fabrication of long slim tubular components for power reactors and the construction of irradiation loops and rigs, are outlined. The processes include hydraulic forming for fabrication of various types of tubes and outer cases of fuel transfer buckets, various specialised welding operations including some applications of the TIG process, and induction brazing of specialised assemblies. (U.K.)

  2. Photocatalytic Graphene-TiO2 Thin Films Fabricated by Low-Temperature Ultrasonic Vibration-Assisted Spin and Spray Coating in a Sol-Gel Process

    Directory of Open Access Journals (Sweden)

    Fatemeh Zabihi

    2017-05-01

    Full Text Available In this work, we communicate a facile and low temperature synthesis process for the fabrication of graphene-TiO2 photocatalytic composite thin films. A sol-gel chemical route is used to synthesize TiO2 from the precursor solutions and spin and spray coating are used to deposit the films. Excitation of the wet films during the casting process by ultrasonic vibration favorably influences both the sol-gel route and the deposition process, through the following mechanisms. The ultrasound energy imparted to the wet film breaks down the physical bonds of the gel phase. As a result, only a low-temperature post annealing process is required to eliminate the residues to complete the conversion of precursors to TiO2. In addition, ultrasonic vibration creates a nanoscale agitating motion or microstreaming in the liquid film that facilitates mixing of TiO2 and graphene nanosheets. The films made based on the above-mentioned ultrasonic vibration-assisted method and annealed at 150 °C contain both rutile and anatase phases of TiO2, which is the most favorable configuration for photocatalytic applications. The photoinduced and photocatalytic experiments demonstrate effective photocurrent generation and elimination of pollutants by graphene-TiO2 composite thin films fabricated via scalable spray coating and mild temperature processing, the results of which are comparable with those made using lab-scale and energy-intensive processes.

  3. Luminescence and scintillation enhancement of Y{sub 2}O{sub 3}:Tm transparent ceramic through post-fabrication thermal processing

    Energy Technology Data Exchange (ETDEWEB)

    Chapman, M.G.; Marchewka, M.R. [Department of Materials Science and Engineering, Clemson University, Clemson, SC 29634 (United States); Roberts, S.A.; Schmitt, J.M. [COMSET – Center for Optical Materials Science and Engineering Technologies, Clemson University, Anderson, SC 29625 (United States); McMillen, C. [Department of Chemistry, Clemson University, Clemson, SC 29634 (United States); Kucera, C.J. [COMSET – Center for Optical Materials Science and Engineering Technologies, Clemson University, Anderson, SC 29625 (United States); DeVol, T.A. [Environmental Engineering and Earth Sciences Department, Clemson University, Clemson, SC 29625 (United States); Ballato, J. [Department of Materials Science and Engineering, Clemson University, Clemson, SC 29634 (United States); COMSET – Center for Optical Materials Science and Engineering Technologies, Clemson University, Anderson, SC 29625 (United States); Jacobsohn, L.G., E-mail: luiz@clemson.edu [Department of Materials Science and Engineering, Clemson University, Clemson, SC 29634 (United States); COMSET – Center for Optical Materials Science and Engineering Technologies, Clemson University, Anderson, SC 29625 (United States)

    2015-09-15

    The effects of post-fabrication thermal processing in O{sub 2} flux on the luminescence and scintillation of a Y{sub 2}O{sub 3}:Tm transparent ceramic were investigated. The results showed that the strategy of post-fabrication processing can be beneficial to the performance of the ceramics, depending on the cumulative processing time. After the first hour of processing, about 40% enhancement in the luminescence output together with about 20% enhancement in the scintillation light yield were obtained. The enhancements were tentatively assigned to the incorporation of oxygen into vacancy sites. Longer cumulative processing times lead to the incorporation of oxygen as interstitials that is detrimental to scintillation light yield but not to luminescence output. This work also revealed that thermoluminescence measurements are a useful tool to predict scintillation light yield of Y{sub 2}O{sub 3}:Tm. - Highlights: • Scintillation and PL enhancement of transparent ceramics through thermal processing. • First thermoluminescence measurements of Y{sub 2}O{sub 3}:Tm above room temperature. • Observation of correlation between TL and scintillation light yield results.

  4. Fabrication of highly nonlinear germano-silicate glass optical fiber incorporated with PbTe semiconductor quantum dots using atomization doping process and its optical nonlinearity.

    Science.gov (United States)

    Ju, Seongmin; Watekar, Pramod R; Han, Won-Taek

    2011-01-31

    Germano-silicate glass optical fiber incorporated with PbTe semiconductor quantum dots (SQDs) in the core was fabricated by using the atomization process in modified chemical vapor deposition (MCVD) process. The absorption bands attributed to PbTe semiconductor quantum dots in the fiber core were found to appear at around 687 nm and 1055 nm. The nonlinear refractive index measured by the long-period fiber grating (LPG) pair method upon pumping with laser diode at 976.4 nm was estimated to be ~1.5 × 10(-16) m2/W.

  5. Fabrication of metallic nanostructures of sub-20 nm with an optimized process of E-beam lithography and lift-off

    KAUST Repository

    Yue, Weisheng

    2012-01-01

    A process consisting of e-beam lithography and lift-off was optimized to fabricate metallic nanostructures. This optimized process successfully produced gold and aluminum nanostructures with features size less than 20 nm. These structures range from simple parallel lines to complex photonic structures. Optical properties of gold split ring resonators (SRRs) were characterized with Raman spectroscopy. Surface-Enhanced Raman Scattering (SERS) on SRRs was observed with 4-mercaptopyridine (4-MPy) as molecular probe and greatly enhanced Raman scattering was observed. Copyright © 2012 American Scientific Publishers.

  6. Influence of Al2O3 particles on the microstructure and mechanical properties of copper surface composites fabricated by friction stir processing

    Directory of Open Access Journals (Sweden)

    L. Suvarna Raju

    2014-12-01

    Full Text Available The influence of three factors, such as volume percentage of reinforcement particles (i.e. Al2O3, tool tilt angle and concave angle of shoulder, on the mechanical properties of Cu–Al2O3 surface composites fabricated via friction stir processing was studied. Taguchi method was used to optimize these factors for maximizing the mechanical properties of surface composites. The fabricated surface composites were examined by optical microscope for dispersion of reinforcement particles. It was found that Al2O3 particles are uniformly dispersed in the stir zone. The tensile properties of the surface composites increased with the increase in the volume percentage of the Al2O3 reinforcement particles. This is due to the addition of the reinforcement particles which increases the temperature of recrystallization by pinning the grain boundaries of the copper matrix and blocking the movement of the dislocations. The observed mechanical properties are correlated with microstructure and fracture features.

  7. Photoconductivity and surface chemical analysis of ZnO thin films deposited by solution-processing techniques for nano and microstructure fabrication

    International Nuclear Information System (INIS)

    Dwivedi, V. K.; Prakash, G. Vijaya; Srivastava, P.

    2013-01-01

    The fabrication of zinc oxide (ZnO) from inexpensive solution-processing techniques, namely, electrochemical deposition and electrospinning were explored on various conducting and mesoporous semiconducting surfaces. Optimised conditions were derived for template- and self-assisted nano/micro structures and composites. ZnO thin films were annealed at a fixed temperature under ambient conditions and characterised using physical and optical techniques. The photocurrent response in the UV region shows a fast rise and double decay behaviour with a fast component followed by a slow oscillatory decay. Photocurrent results were correlated with surface chemical analysis from X-ray photoelectron spectroscopy. Various characterisation details reveal the importance of fabrication parameter optimisation for useful low-cost optoelectronic applications. (semiconductor materials)

  8. True and intentionally fabricated memories

    OpenAIRE

    Justice, L.V.; Morrison, C.M.; Conway, M. A.

    2012-01-01

    The aim of the experiment reported here was to investigate the processes underlying the construction of truthful and deliberately fabricated memories. Properties of memories created to be intentionally false - fabricated memories - were compared to properties of memories believed to be true - true memories. Participants recalled and then wrote or spoke true memories and fabricated memories of everyday events. It was found that true memories were reliably more vivid than fabricated memories an...

  9. Processing parameters investigation for the fabrication of self-supported and freeform polymeric microstructures using ultraviolet-assisted three-dimensional printing

    International Nuclear Information System (INIS)

    Farahani, R D; Lebel, L L; Therriault, D

    2014-01-01

    Ultraviolet-assisted three-dimensional (3D) printing (UV-3DP) was used to manufacture photopolymer-based microdevices with 3D self-supported and freeform features. The UV-3DP technique consists of the robotized deposition of extruded filaments, which are rapidly photopolymerized under UV illumination during the deposition process. This paper systematically studies the processing parameters of the UV-3DP technique using two photo-curable polymers and their associated nanocomposite materials. The main processing parameters including materials' rheological behavior, deposition speed and extrusion pressure, and UV illumination conditions were thoroughly investigated. A processing map was then defined in order to help choosing the proper parameters for the UV-3DP of microstructures with various geometries. Compared to self-supported features, the accurate fabrication of 3D freeform structures was found to take place in a narrower processing region since a higher rigidity of the extruded filament was required for structural stability. Finally, various 3D self-supported and freeform microstructures with high potential in micro electromechanical systems, micro-systems and organic electronics were fabricated to show the capability of the technique. (paper)

  10. Implementation of the design attendent by computers (CAD) for the location of structures of power transmission lines; Implementacion del diseno asistido por computadora para la localizacion de estructuras de lineas de transmision

    Energy Technology Data Exchange (ETDEWEB)

    Vega Ortiz, Miguel; Gutierrez Arriola, Gustavo [Instituto de Investigaciones Electricas, Temixco, Morelos (Mexico)

    2000-07-01

    In order that the tools of CAD (Design Attended by Computer) that are offered in the market are really useful, they must combine the criteria and experiences of the expert designers with the specifications and practices established in the electrical company. This includes, from the introduction to the information system of the available input data and its design criteria, to obtaining the required output information. In the present work the methodology developed by the Instituto de Investigaciones Electricas (IIE) in the design of power transmission lines that integrates the Comision Federal de Electricidad (CFE) requirements in the design of its transmission power lines is an advanced computer tool that results in obtaining better designs. Some of the most important aspects are the reduction of the used working time, the cost of the designed line, its reliability, the flexibility in the information handling and the quality of presentation. [Spanish] Para que las herramientas de diseno asistido por computadora que se ofrecen en el mercado sean realmente utiles deben conjuntar los criterios y experiencias de los disenadores expertos con las especificaciones y practicas establecidas en la empresa electrica. Esto incluye desde la introduccion al sistema de la informacion de datos de entrada de la que se dispone y de sus criterios de diseno hasta la obtencion de la informacion de salida que se requiere. En el presente trabajo se resume la metodologia desarrollada por el Instituto de Investigaciones Electricas (IIE) en el diseno de lineas de transmision, que integra los requerimientos de la Comision Federal de Electricidad (CFE) en el diseno de sus lineas de transmision en una herramienta de computo avanzada y que redunda en la obtencion de mejores disenos. Algunos de los aspectos mas importantes son la reduccion del tiempo de trabajo empleado, el costo de la linea disenada, su confiabilidad, la flexibilidad en el manejo de informacion y la calidad de presentacion.

  11. Software for the design of acoustical steam silencers of the reaction-absorption type; Software para el diseno de silenciadores acusticos de vapor del tipo reaccion-absorcion

    Energy Technology Data Exchange (ETDEWEB)

    Buendia Dominguez, Eduardo H.; Alvarez Chavez, Jose M. [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1989-12-31

    This paper describes the computer program named SILRA, that determines the outline dimensions of an acoustic steam silencer of the reaction-absorption type. These silencers are employed in the geothermoelectric power plants to lower the high levels of pressure and sound caused by the steam discharge to the surrounding atmosphere. The program has the capacity of predicting the noise level generated by the discharge without silencer depending on the emitting source. On SIRLA was successfully coupled the theory described in specialized literature with optimization techniques and experiences acquired in former designs. SIRLA is a powerful tool that allows the designer to optimize the equipment as well as the design time. [Espanol] En este trabajo se describe el programa de computo SILRA, que determina las dimensiones generales de un silenciador acustico de vapor tipo reaccion-absorcion, estos silenciadores se emplean en las centrales geotermoelectricas para abatir los altos niveles de presion de sonido provocados por la descarga del vapor a la atmosfera. El programa tiene la capacidad de predecir el nivel de ruido que genera la descarga sin silenciador, dependiendo de la fuente emisora. En SILRA se acoplaron con exito la teoria descrita en la literatura especializada con tecnicas de optimacion y experiencias adquiridas en disenos anteriores. SILRA es una poderosa herramienta que permite al disenador optimar tanto el equipo como el tiempo de diseno.

  12. Diseno de una Actividad de Aprendizaje Basada en la Argumentacion Dialogica en un curso Virtual de Biotecnologia y su Incidencia en el Desarrollo de Competencias Cientificas

    Science.gov (United States)

    Ortiz Benavides, Fedra Lorena

    El proposito de la investigacion fue evaluar la efectividad de una actividad de aprendizaje basado en la argumentacion dialogica en linea y su incidencia en el desarrollo de competencias cientificas. Se fundamenta en la teoria del aprendizaje socio cultural de Vigotsky (1984), los principios del diseno instruccional de la cognicion situada por Hung y Der-Thang (2001) y como estrategia se aplico la argumentacion dialogica utilizando el Modelo Argumentativo de Toulmin MAT (1984). El diseno experimental comparo dos grupos de estudiantes A y B en el curso virtual de Biotecnologia. El grupo A (experimental) desarrollo la discusion a partir de la estrategia disenada para este estudio y el grupo B (control) realizo la discusion desde las actividades tradicionales. El desarrollo de la competencia argumentativa se valoro con el instrumento de evaluacion para argumentacion dialogica en linea propuesta por Clark y Sampson (2008). La evaluacion de las competencias cientificas se realizo a partir de una postprueba. Los datos fueron analizados con pruebas estadisticas no parametricas. Los resultados de la investigacion, indicaron diferencias significativas en el nivel de la competencia argumental en el grupo experimental en comparacion al grupo control. Igualmente se demostro que existe una relacion positiva entre el nivel de desarrollo de la competencia argumentativa y el nivel de desarrollo de las competencias cientificas.

  13. A novel micro/nano fabrication process based on the combined use of dielectrophoresis, electroosmotic flow, and electrodeposition for surface patterning

    Science.gov (United States)

    Perez-Gonzalez, Victor H.; Ho, Vinh; Vazquez-Pinon, Matias; Martinez-Chapa, Sergio O.; Kulinsky, Lawrence

    2015-11-01

    In this work, a novel application of electrokinetic forces is presented. Employing a gold interdigitated electrode array (IDEA), dielectrophoresis (a force acting on polarizable material) and electroosmosis (a force acting on ionic fluids) were utilized as microfabrication tools. Through electroosmotic flow, particles were dragged toward dielectrophoretic trapping zones, where they were held. Then polypyrrole, an electroconductive material with good mechanical and electrical properties, wide electrochemical window, and ease of fabrication, was electrodeposited onto the gold IDEA surface, permanently entrapping the microparticles within the structure. The process was tested employing organic (polystyrene), inorganic (silicon), and biologic (yeast cells) microparticles, all of which were successfully trapped. Computational models were developed to predict the electrokinetic response of the microparticles and compared to experimental observations. It was demonstrated that this process can be used to produce hierarchical structures through sequential repetition of entrapment cycles. Additionally, it is compatible with the Carbon-MEMS process. The fabrication process presented in this paper opens a wide range of applications that include: energy storage devices, scaffolds for cell culture, biomedical devices, electrochemical sensors, electrokinetic devices, among many others.

  14. Effects of Process Parameters on the Characteristics of Mixed-Halide Perovskite Solar Cells Fabricated by One-Step and Two-Step Sequential Coating.

    Science.gov (United States)

    Ahmadian-Yazdi, Mohammad Reza; Zabihi, Fatemeh; Habibi, Mehran; Eslamian, Morteza

    2016-12-01

    In this paper, two-step sequential spin-dip and spin-spin coating, as well as one-step spin coating, methods are used to fabricate methylammonium lead mixed-halide perovskites to study the effect of process parameters, including the choice of the solvent, annealing temperature, spin velocity, and dipping time on the characteristics of the perovskite film. Our results show that using a mixture of DMF and DMSO, with volume ratio of 1:1, as the organic solvents for PbCl2 results in the best mixed-halide perovskite because of the effective coordination between DMSO and PbCl2. Surface dewetting due to two effects, i.e., crystallization and thin liquid film instability, is observed and discussed, where an intermediate spin velocity of about 4000 rpm is found suitable to suppress dewetting. The perovskite film fabricated using the one-step method followed by anti-solvent treatment shows the best perovskite conversion in XRD patterns, and the planar device fabricated using the same method exhibited the highest efficiency among the employed methods. The perovskite layer made by sequential spin-dip coating is found thicker with higher absorbance, but the device shows a lower efficiency because of the challenges associated with perovskite conversion in the sequential method. The one-step deposition method is found easier to control and more promising than the sequential deposition methods.

  15. Surface processing and ageing behavior of silk fabrics treated with atmospheric-pressure plasma for pigment-based ink-jet printing

    Science.gov (United States)

    Zhang, Chunming; Wang, Libing; Yu, Miao; Qu, Lijun; Men, Yajing; Zhang, Xiangwu

    2018-03-01

    Pigment inkjet printing has highlighted the advantages of cost-effective, short production cycle and environment-friendly. However, patterns directly printed with pigment inks usually have low color yields and blurry images which are caused by bleeding phenomenon. This work presents an atmospheric-pressure plasma method for improving the pigment-based ink-jet printing performance of silk fabrics. The effects of surface changes induced are discussed, with data derived from morphological study by atomic force microscopy (AFM), chemical analysis using X-ray photoelectron spectroscopy (XPS) and contact angle measurement. Ink-jet printing experiments were conducted to study the influence of measured changes on anti-bleeding property and color strength of treated and original samples. The ageing experiment indicates that the modified silk fabrics should be printed within 24 h after plasma processing for maximum color yields. This study explores an effective approach for the atmospheric-pressure plasma, which can provide its significant use in improving the surface properties and ink-jet printing performance of fabrics.

  16. Fabrication of low-cost beta-type Ti-Mn alloys for biomedical applications by metal injection molding process and their mechanical properties.

    Science.gov (United States)

    Santos, Pedro Fernandes; Niinomi, Mitsuo; Liu, Huihong; Cho, Ken; Nakai, Masaaki; Itoh, Yoshinori; Narushima, Takayuki; Ikeda, Masahiko

    2016-06-01

    Titanium and its alloys are suitable for biomedical applications owing to their good mechanical properties and biocompatibility. Beta-type Ti-Mn alloys (8-17 mass% Mn) were fabricated by metal injection molding (MIM) as a potential low cost material for use in biomedical applications. The microstructures and mechanical properties of the alloys were evaluated. For up to 13 mass% Mn, the tensile strength (1162-938MPa) and hardness (308-294HV) of the MIM fabricated alloys are comparable to those of Ti-Mn alloys fabricated by cold crucible levitation melting. Ti-9Mn exhibits the best balance of ultimate tensile strength (1046MPa) and elongation (4.7%) among the tested alloys, and has a Young's modulus of 89GPa. The observed low elongation of the alloys is attributed to the combined effects of high oxygen content, with the presence of interconnected pores and titanium carbides, the formation of which is due to carbon pickup during the debinding process. The elongation and tensile strength of the alloys decrease with increasing Mn content. The Ti-Mn alloys show good compressive properties, with Ti-17Mn showing a compressive 0.2% proof stress of 1034MPa, and a compressive strain of 50%. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Design and analysis of an intelligent public FV lighting system; Diseno y analisis de un alumbrado publico FV inteligente

    Energy Technology Data Exchange (ETDEWEB)

    Hanessian D, Ana V.; Gordon, Manuel [Universidad Autonoma Metropolitana, Unidad Azcapotzalco, Mexico, D.F. (Mexico)

    2009-07-01

    In the Mexico's National Energy Balance of 2008, it is considered that of the total of the electrical power consumption in our country, 18% is dedicated to lighting. Conscious of the necessity of saving energy in public lighting in this article is presented the design, construction and analysis of the power consumption of a public light fed with electricity of photovoltaic cells and the control of intensity on the light in inverse way of the natural light. A lamp constructed based in light emitting diodes (LEDs) is used. This has the quality of consuming very little energy that could be provided by the sun and be stored to use it at night. With this system, proven at scale, energy savings are obtained superior to 50% of the conventional one and, in relation to the commercial photovoltaic (FV) luminaries up to 30%. [Spanish] Del Balance Nacional de Energia, de Mexico, de 2008, se considera que del total del consumo de energia electrica en nuestro pais, el 18% esta dedicado a la iluminacion. Conscientes de la necesidad de ahorrar energia en alumbrado publico, en este articulo se presenta el diseno de construccion y analisis del consumo energetico de una luminaria publica alimentada con electricidad de celdas fotovoltaicas y el control de intensidad de la luz de manera inversa a la luz natural. Se utiliza un foco construido a base a los diodos emisores de luz (LEDs, por sus siglas en ingles). Estos tienen la cualidad de consumir muy poca energia que podra ser suministrada por el sol y almacenada para utilizarla en la noche. Con este sistema, probado a escala, se logran ahorros de energia superiores al 50% del convencional y, en relacion a las luminarias fotovoltaicas (FV) comerciales, hasa el 30%.

  18. Fabrication of ultrathin MIL-96(Al) films and study of CO2adsorption/desorption processes using quartz crystal microbalance.

    Science.gov (United States)

    Andrés, Miguel A; Benzaqui, M; Serre, C; Steunou, N; Gascón, I

    2018-06-01

    This contribution reports the fabrication and characterization of ultrathin films of nanoparticles of the water stable microporous Al tricarboxylate metal organic framework MIL-96(Al). The preparation of MOF dispersions in chloroform has been optimized to obtain dense monolayer films of good quality, without nanoparticle agglomeration, at the air-water interface that can be deposited onto solid substrates of different nature without any previous substrate functionalization. The MOF studied shows great interest for CO 2 capture because it presents Al 3+ Lewis centers and hydroxyl groups that strongly interact with CO 2 molecules. A comparative CO 2 adsorption study on drop-cast, Langmuir-Blodgett (LB) and Langmuir-Schaefer (LS) films using a Quartz Crystal Microbalance-based setup (QCM) has revealed that the CO 2 uptake depends strongly on the film fabrication procedure and the storage conditions. Noteworthy the CO 2 adsorption capacity of LB films is increased by 30% using a simple and green treatment (immersion of the film into water during 12 h just after film preparation). Finally, the stability of LB MOF monolayers upon several CO 2 adsorption/desorption cycles has been demonstrated, showing that CO 2 can be easily desorbed from the films at 303 K by flowing an inert gas (He). These results show that MOF LB monolayers can be of great interest for the development of MOF-based devices that require the use of very small MOF quantities, especially gas sensors. Copyright © 2018 Elsevier Inc. All rights reserved.

  19. Effects of the fabrication process on the grain-boundary resistance in BaZr0.9Y0.1O3-δ

    DEFF Research Database (Denmark)

    Ricote, Sandrine; Bonanos, Nikolaos; Manerbino, A.

    2014-01-01

    This paper reports on the effect of the fabrication process on the conductivity of BZY10 (BaZr0.9Y0.1O3-δ). The dense specimens were prepared by four methods: (1) solid-state reactive sintering (SSRS), (2) conventional sintering using powder prepared by solid-state reaction and NiO as sintering aid...... measured by impedance spectroscopy in moist reducing atmosphere from 600 to 200° C; the grain boundary and bulk contributions were distinguished by the analysis of the low-temperature spectra. The grain-boundaries of the sample prepared by solid-state reactive sintering exhibited a resistance typical...

  20. Study of microstructure, texture and mechanical properties of Zr–2.5Nb alloy pressure tubes fabricated with different processing routes

    International Nuclear Information System (INIS)

    Saibaba, N.; Vaibhaw, Kumar; Neogy, S.; Mani Krishna, K.V.; Jha, S.K.; Phani Babu, C.; Ramana Rao, S.V.; Srivastava, D.; Dey, G.K.

    2013-01-01

    Different fabrication trials involving the variation in three important stages of Zr–2.5Nb pressure tube were undertaken. The variations were with respect to the mode of breaking the cast structure of the ingot (forging vs extrusion), the hot extrusion ratio and the number of subsequent cold work stages to produce the finished tube. It was observed that the forging process resulted in superior performance in breaking the cast structure. Higher extrusion ratios resulted in more favorable texture and microstructure. More continuity of the beta phase was observed in the final microstructure for the route involving the single cold work step subsequent to hot extrusion

  1. Trivalued Memory Circuit Using Metal-Oxide-Semiconductor Field-Effect Transistor Bipolar-Junction-Transistor Negative-Differential-Resistance Circuits Fabricated by Standard SiGe Process

    Science.gov (United States)

    Gan, Kwang-Jow; Tsai, Cher-Shiung; Liang, Dong-Shong; Wen, Chun-Ming; Chen, Yaw-Hwang

    2006-09-01

    A trivalued memory circuit based on two cascoded metal-oxide-semiconductor field-effect transistor bipolar-junction-transistor negative-differential-resistance (MOS-BJT-NDR) devices is investigated. The MOS-BJT-NDR device is made of MOS and BJT devices, but it can show the NDR current-voltage characteristic by suitably arranging the MOS parameters. We demonstrate a trivalued memory circuit using the two-peak MOS-BJT-NDR circuit as the driver and a resistor as the load. The MOS-BJT-NDR devices and memory circuits are fabricated by the standard 0.35 μm SiGe process.

  2. Fabrication and Characterization of 3D-Printed Highly-Porous 3D LiFePO4 Electrodes by Low Temperature Direct Writing Process

    Science.gov (United States)

    Cheng, Xingxing; Li, Bohan; Chen, Zhangwei; Mi, Shengli; Lao, Changshi

    2017-01-01

    LiFePO4 (LFP) is a promising cathode material for lithium-ion batteries. In this study, low temperature direct writing (LTDW)-based 3D printing was used to fabricate three-dimensional (3D) LFP electrodes for the first time. LFP inks were deposited into a low temperature chamber and solidified to maintain the shape and mechanical integrity of the printed features. The printed LFP electrodes were then freeze-dried to remove the solvents so that highly-porous architectures in the electrodes were obtained. LFP inks capable of freezing at low temperature was developed by adding 1,4 dioxane as a freezing agent. The rheological behavior of the prepared LFP inks was measured and appropriate compositions and ratios were selected. A LTDW machine was developed to print the electrodes. The printing parameters were optimized and the printing accuracy was characterized. Results showed that LTDW can effectively maintain the shape and mechanical integrity during the printing process. The microstructure, pore size and distribution of the printed LFP electrodes was characterized. In comparison with conventional room temperature direct ink writing process, improved pore volume and porosity can be obtained using the LTDW process. The electrochemical performance of LTDW-fabricated LFP electrodes and conventional roller-coated electrodes were conducted and compared. Results showed that the porous structure that existed in the printed electrodes can greatly improve the rate performance of LFP electrodes. PMID:28796182

  3. Fabrication and Characterization of 3D-Printed Highly-Porous 3D LiFePO4 Electrodes by Low Temperature Direct Writing Process

    Directory of Open Access Journals (Sweden)

    Changyong Liu

    2017-08-01

    Full Text Available LiFePO4 (LFP is a promising cathode material for lithium-ion batteries. In this study, low temperature direct writing (LTDW-based 3D printing was used to fabricate three-dimensional (3D LFP electrodes for the first time. LFP inks were deposited into a low temperature chamber and solidified to maintain the shape and mechanical integrity of the printed features. The printed LFP electrodes were then freeze-dried to remove the solvents so that highly-porous architectures in the electrodes were obtained. LFP inks capable of freezing at low temperature was developed by adding 1,4 dioxane as a freezing agent. The rheological behavior of the prepared LFP inks was measured and appropriate compositions and ratios were selected. A LTDW machine was developed to print the electrodes. The printing parameters were optimized and the printing accuracy was characterized. Results showed that LTDW can effectively maintain the shape and mechanical integrity during the printing process. The microstructure, pore size and distribution of the printed LFP electrodes was characterized. In comparison with conventional room temperature direct ink writing process, improved pore volume and porosity can be obtained using the LTDW process. The electrochemical performance of LTDW-fabricated LFP electrodes and conventional roller-coated electrodes were conducted and compared. Results showed that the porous structure that existed in the printed electrodes can greatly improve the rate performance of LFP electrodes.

  4. Properties of grain boundaries in bulk, melt processed Y-Ba-Cu-O fabricated using bridge-shaped seeds

    Science.gov (United States)

    Shi, Y.-H.; Durrell, J. H.; Dennis, A. R.; Babu, N. Hari; Mancini, C. E.; Cardwell, D. A.

    2012-04-01

    Single grain RE-Ba-Cu-O ((RE)BCO, where RE is a rare earth element or yttrium) bulk superconducting materials have significant potential for a variety of engineering applications due to their ability to trap high magnetic fields. However, it is well known that the presence of grain boundaries coupled with a high angle of misorientation (typically 5°) significantly reduces the critical current density, Jc, in all forms of high temperature superconducting materials. It is of considerable fundamental and technological interest, therefore, to investigate the grain boundary properties of bulk, film and tape (RE)BCO. We report a successful multi-seeding technique for the fabrication of fully aligned, artificial (0° misalignment) grain boundaries within large grain YBCO bulk superconductors using bridge-shaped seeds. The microstructure and critical current densities of the grain boundaries produced by this technique have been studied in detail.

  5. Properties of grain boundaries in bulk, melt processed Y–Ba–Cu–O fabricated using bridge-shaped seeds

    International Nuclear Information System (INIS)

    Shi, Y-H; Durrell, J H; Dennis, A R; Mancini, C E; Cardwell, D A; Hari Babu, N

    2012-01-01

    Single grain RE–Ba–Cu–O ((RE)BCO, where RE is a rare earth element or yttrium) bulk superconducting materials have significant potential for a variety of engineering applications due to their ability to trap high magnetic fields. However, it is well known that the presence of grain boundaries coupled with a high angle of misorientation (typically 5°) significantly reduces the critical current density, J c , in all forms of high temperature superconducting materials. It is of considerable fundamental and technological interest, therefore, to investigate the grain boundary properties of bulk, film and tape (RE)BCO. We report a successful multi-seeding technique for the fabrication of fully aligned, artificial (0° misalignment) grain boundaries within large grain YBCO bulk superconductors using bridge-shaped seeds. The microstructure and critical current densities of the grain boundaries produced by this technique have been studied in detail. (paper)

  6. Digital fabrication

    CERN Document Server

    2012-01-01

    The Winter 2012 (vol. 14 no. 3) issue of the Nexus Network Journal features seven original papers dedicated to the theme “Digital Fabrication”. Digital fabrication is changing architecture in fundamental ways in every phase, from concept to artifact. Projects growing out of research in digital fabrication are dependent on software that is entirely surface-oriented in its underlying mathematics. Decisions made during design, prototyping, fabrication and assembly rely on codes, scripts, parameters, operating systems and software, creating the need for teams with multidisciplinary expertise and different skills, from IT to architecture, design, material engineering, and mathematics, among others The papers grew out of a Lisbon symposium hosted by the ISCTE-Instituto Universitario de Lisboa entitled “Digital Fabrication – A State of the Art”. The issue is completed with four other research papers which address different mathematical instruments applied to architecture, including geometric tracing system...

  7. SU-E-T-61: A Practical Process for Fabricating Passive Scatter Proton Beam Modulation Compensation Filters Using 3D Printing

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, T; Drzymala, R [Washington University School of Medicine, St. Louis, MO (United States)

    2015-06-15

    Purpose: The purpose of this project was to devise a practical fabrication process for passive scatter proton beam compensation filters (CF) that is competitive in time, cost and effort using 3D printing. Methods: DICOM compensator filter files for a proton beam were generated by our Eclipse (Varian, Inc.) treatment planning system. The compensator thickness specifications were extracted with in-house software written in Matlab (MathWorks, Inc.) code and written to a text file which could be read by the Rhinoceros 5, computer-aided design (CAD) package (Robert McNeel and Associates), which subsequently generated a smoothed model in a STereoLithographic also known as a Standard Tesselation Language file (STL). The model in the STL file was subsequently refined using Netfabb software and then converted to printing instructions using Cura. version 15.02.1. for our 3D printer. The Airwolf3D, model HD2x, fused filament fabrication (FFF) 3D printer (Airwolf3D.com) was used for our fabrication system with a print speed of 150mm per second. It can print in over 22 different plastic filament materials in a build volume of 11” x 8” x 12”. We choose ABS plastic to print the 3D model of the imprint for our CFs. Results: Prints of the CF could be performed at a print speed of 70mm per second. The time to print the 3D topology for the CF for the 14 cm diameter snout of our Mevion 250 proton accelerator was less than 3 hours. The printed model is intended to subsequently be used as a mold to imprint a molten wax cylindrical to form the compensation after cooling. The whole process should be performed for a typical 3 beam treatment plan within a day. Conclusion: Use of 3D printing is practical and can be used to print a 3D model of a CF within a few hours.

  8. SU-E-T-61: A Practical Process for Fabricating Passive Scatter Proton Beam Modulation Compensation Filters Using 3D Printing

    International Nuclear Information System (INIS)

    Zhao, T; Drzymala, R

    2015-01-01

    Purpose: The purpose of this project was to devise a practical fabrication process for passive scatter proton beam compensation filters (CF) that is competitive in time, cost and effort using 3D printing. Methods: DICOM compensator filter files for a proton beam were generated by our Eclipse (Varian, Inc.) treatment planning system. The compensator thickness specifications were extracted with in-house software written in Matlab (MathWorks, Inc.) code and written to a text file which could be read by the Rhinoceros 5, computer-aided design (CAD) package (Robert McNeel and Associates), which subsequently generated a smoothed model in a STereoLithographic also known as a Standard Tesselation Language file (STL). The model in the STL file was subsequently refined using Netfabb software and then converted to printing instructions using Cura. version 15.02.1. for our 3D printer. The Airwolf3D, model HD2x, fused filament fabrication (FFF) 3D printer (Airwolf3D.com) was used for our fabrication system with a print speed of 150mm per second. It can print in over 22 different plastic filament materials in a build volume of 11” x 8” x 12”. We choose ABS plastic to print the 3D model of the imprint for our CFs. Results: Prints of the CF could be performed at a print speed of 70mm per second. The time to print the 3D topology for the CF for the 14 cm diameter snout of our Mevion 250 proton accelerator was less than 3 hours. The printed model is intended to subsequently be used as a mold to imprint a molten wax cylindrical to form the compensation after cooling. The whole process should be performed for a typical 3 beam treatment plan within a day. Conclusion: Use of 3D printing is practical and can be used to print a 3D model of a CF within a few hours

  9. High-Rate Fabrication of a-Si-Based Thin-Film Solar Cells Using Large-Area VHF PECVD Processes

    Energy Technology Data Exchange (ETDEWEB)

    Deng, Xunming [University of Toledo; Fan, Qi Hua

    2011-12-31

    The University of Toledo (UT), working in concert with it’s a-Si-based PV industry partner Xunlight Corporation (Xunlight), has conducted a comprehensive study to develop a large-area (3ft x 3ft) VHF PECVD system for high rate uniform fabrication of silicon absorber layers, and the large-area VHF PECVD processes to achieve high performance a-Si/a-SiGe or a-Si/nc-Si tandem junction solar cells during the period of July 1, 2008 to Dec. 31, 2011, under DOE Award No. DE-FG36-08GO18073. The project had two primary goals: (i) to develop and improve a large area (3 ft × 3 ft) VHF PECVD system for high rate fabrication of > = 8 Å/s a-Si and >= 20 Å/s nc-Si or 4 Å/s a-SiGe absorber layers with high uniformity in film thicknesses and in material structures. (ii) to develop and optimize the large-area VHF PECVD processes to achieve high-performance a-Si/nc-Si or a-Si/a-SiGe tandem-junction solar cells with >= 10% stable efficiency. Our work has met the goals and is summarized in “Accomplishments versus goals and objectives”.

  10. Fabrication of organic FETs based on printing techniques and the improvement of FET properties by the insertion of solution-processable buffer layers

    Science.gov (United States)

    Itoh, Eiji; Kanamori, Akira

    2016-04-01

    In this study, we developed multilayer deposition and patterning processes that can be used to fabricate all-printed, organic field-effect transistors (OFETs) on the basis of vacuum-free, solution-processable soft-lithography techniques. We have used regioregular poly(3-hexylthiophene) (P3HT) as a soluble p-type polymer semiconductor and (6,6)-phenyl C61 butyric acid methyl ester (PCBM) as a soluble n-type semiconductor, and cross-linked poly(vinyl phenol) (CL-PVP) as a low-temperature (OFETs with multiwalled carbon nanotubes (MWCNTs), silver nanoparticles (NPs), and their composites (or multilayers) as printed source-drain (S-D) electrodes in order to fabricate vacuum-free, all-printed OFETs. The P3HT-OFETs with MWCNT S-D electrodes exhibited higher hole mobility and on/off ratios than the devices with Ag NP S-D electrodes owing to better contact at the MWCNT/P3HT interface. On the other hand, Ag/molybdenum oxide (MoO3) S-D electrodes considerably enhanced the hole injection and caused the reduction in the on/off ratio and the difficulty in turning off the devices. The PCBM-OFETs with MWCNT S-D electrodes also exhibited higher electron mobility that is almost comparable to that of P3HT-OFETs and lower threshold voltage, which was considered to be due to the enhanced electron injection at the electrode interface.

  11. Fabrication of silicon-carbide continuous fiber reinforced carbon (SiC/C) composites using hot press process and the effects of fiber forms on the strength

    International Nuclear Information System (INIS)

    Chang, Tong-Shik; Okura, Akimitsu

    1988-01-01

    Silicon-carbide continuous fiber reinforced carbon (SiC/C) composites was fabricated using a simple hot press process. Three forms of SiC fiber reinforcement, that is, cloth, mat and unidirectional long fibers (UD fibers) were employed. Fine pulverized coke mixed with carbonaceous bulk mesophase (BM) was used as matrix. In this process, SiC fibers were laminated alternately with the matrix admixture in a die, and then heated to 600deg C under a pressure of 49 MPa. The results were as follows: (1) The maximum strengths of the composites were the greatest for the UD fiber reinforcements at 121.5 MPa while the cloth and mat reinforcements showed appreciably lower strengths. (2) After secondary heat treatments at 800deg C to 1500deg C, the composite reinforced with UD fibers showed excellent strengths above 106 MPa which were greater than that of an as-fabricated commercial C/C composite. The strengths of the composites reinforced with cloth and mat, however, were significantly reduced by the heat treatments. (author)

  12. Evaluation and Optimization of a Hybrid Manufacturing Process Combining Wire Arc Additive Manufacturing with Milling for the Fabrication of Stiffened Panels

    Directory of Open Access Journals (Sweden)

    Fang Li

    2017-11-01

    Full Text Available This paper proposes a hybrid WAAM (wire arc additive manufacturing and milling process (HWMP, and highlights its application in the fabrication of stiffened panels that have wide applications in aviation, aerospace, and automotive industries, etc. due to their light weight and strong load-bearing capability. In contrast to existing joining or machining methods, HWMP only deposits stiffeners layer-by-layer onto an existing thin plate, followed by minor milling of the irregular surfaces, which provides the possibility to significantly improve material utilization and efficiency without any loss of surface quality. In this paper, the key performances of HWMP in terms of surface quality, material utilization and efficiency are evaluated systematically, which are the results of the comprehensive effects of the deposition parameters (e.g., travel speed, wire-feed rate and the milling parameters (e.g., spindle speed, tool-feed rate. In order to maximize its performances, the optimization is also performed to find the best combination of the deposition and the milling parameters. The case study shows that HWMP with the optimal process parameters improves the material utilization by 57% and the efficiency by 32% compared against the traditional machining method. Thus, HWMP is believed to be a more environmental friendly and sustainable method for the fabrication of stiffened panels or other similar structures.

  13. Efficient and stable CH3NH3PbI3-x(SCN)x planar perovskite solar cells fabricated in ambient air with low-temperature process

    Science.gov (United States)

    Zhang, Zongbao; Zhou, Yang; Cai, Yangyang; Liu, Hui; Qin, Qiqi; Lu, Xubing; Gao, Xingsen; Shui, Lingling; Wu, Sujuan; Liu, Jun-Ming

    2018-02-01

    Planar perovskite solar cells (PSCs) based on CH3NH3PbI3-x(SCN)x (SCN: thiocyanate) active layer and low-temperature processed TiO2 films are fabricated by a sequential two-step method in ambient air. Here, alkali thiocyanates (NaSCN, KSCN) are added into Pb(SCN)2 precursor to improve the microstructure of CH3NH3PbI3-x(SCN)x perovskite layers and performance of the as-prepared PSCs. At the optimum concentrations of alkali thiocyanates as additives, the as-prepared NaSCN-modified and KSCN-modified PSCs demonstrate the efficiencies of 16.59% and 15.63% respectively, being much higher than 12.73% of the reference PSCs without additives. This improvement is primarily ascribed to the enhanced electron transport, reduced recombination rates and much improved microstructures with large grain size and low defect density at grain boundaries. Importantly, it is revealed that the modified PSCs at the optimized concentrations of alkali thiocyanates additives exhibit remarkably improved stability than the reference PSCs against humid circumstance, and a continuous exposure to humid air without encapsulation over 45 days only records about 5% degradation of the efficiency. These findings provide a facile approach to fabricate efficient and stable PSCs by low processing temperature in ambient air, both of which are highly preferred for future practical applications of PSCs.

  14. Fabrication of solution processed carbon nanotube embedded polyvinyl alcohol composite film for non-volatile memory device.

    Science.gov (United States)

    Kishore, S Chandra; Pandurangan, A

    2014-03-01

    Carbon nanotubes (CNTs) were synthesized by chemical vapor deposition using nickel coated stainless steel prepared by electrophoretic deposition. CNTs were embedded in polyvinyl alcohol (PVA) which acts as an organic insulator to fabricate Si/PVA/CNT/PVA/Al Metal-Insulator-Semiconductor type memory devices. The effect of CNT content in the charge storage capacity of PVA-CNT composite film was investigated. The hysteresis obtained from the capacitance-voltage (CV) measurement resulted in a memory window of 1.9 V with 3% CNT loading with the gate voltage sweep of +/- 6 V at 1 MHz under room temperature. The memory window of the devices was due to electron injection into the CNT charge storage elements from the top electrode through PVA. The extensive pi-conjugation along the CNT axis traps the electrons in the CNT network. The ON/OFF state current ratio of Si/Al/PVA-CNT/AI device with 3% CNT in PVA demonstrated significantly a lower turn-on voltage of -1 V and a higher ON/OFF state current ratio of 10(7). The non-volatile and reprogrammable switching behavior of the device demonstrated the characteristic of a rewritable memory.

  15. Collaboration Patterns and Processes Between Dentists and Dental Laboratories When Planning and Fabricating Implant-Supported Restorations.

    Science.gov (United States)

    Harel, Noga; Meirowitz, Avi; Block, Jonathan; Palti, Ady; Matalon, Shlomo; Ormianer, Zeev

    2017-06-01

    The success of implant-supported restorations is dependent on proper treatment planning, effective communication within the clinical team, and the use of appropriate methods and materials in the dental laboratory. The objective of this study was to determine collaboration trends between dentists and laboratories and to assess the common methods and materials involved in fabricating implant-supported restorations. Questionnaires were distributed to dental laboratories and technicians. Seventy questionnaires were answered and were included in the data analyses. Most of the impressions (87%) were taken using an individual custom-made open tray. In 83% of impressions, screw-retained transfer units were used, and in 61% of cases, the units were splinted. Bite registration was recorded in 91% of the cases. In 80% of cases, articulator setup was done. When matching the shade of a restoration in the anterior, 57% of the technicians do so in collaboration with the dentist, and 39% match the shade independently. Type of restoration and abutment selection were done mainly by the technicians. Abutment selection was reported to be carried out by 72% of the technicians. Generally, dentists and technicians follow the standards recommended in the contemporary literature, especially, in major procedures such as impression taking, bite registration, and articulator setup. However, principal decisions, such as abutment and color shade are done mainly by technicians.

  16. Magnetic Properties of (Nia-ZnbX Cu1-X Ferrite Nanoparticle Fabricated by Sol-Gel Process

    Directory of Open Access Journals (Sweden)

    Yang S.

    2017-06-01

    Full Text Available In future, more mobile devices with different frequencies will be used at the same time. Therefore, it is expected that the trouble caused by wave interference between devices will be further intensified. In order to prevent this trouble, investigation of selective frequency transmission or absorption material is required. In this paper, magnetic properties of nickel-zinc-copper ferrite nano powder was researched as wave absorber. (Nia-ZnbxCu1-xFe2O4(NZCF nanoparticles were fabricated by the sol-gel method. The influence of copper substitution on lattice parameter change was analyzed by X-ray diffraction (XRD, particle size was analyzed by scanning electron microscopy (SEM, and Magnetic properties analyzed by vibrating sample magnetometer (VSM. The NZCF and Nickel-zinc ferrite (NZF lattice parameter difference was 0.028 Å and particle size was calculated as 30 nm with the XRD peak. The VSM results of (Ni0.3-Zn0.30.6Cu1-0.6Fe2O4 annealed sample at 700°C for 3hous were 58.5 emu/g (Ms, 22.8 Oe (Hc. It was the most suitable magnetic properties for wave absorber in this investigation.

  17. Three-dimensional simulation of fabrication process-dependent effects on single event effects of SiGe heterojunction bipolar transistor

    International Nuclear Information System (INIS)

    Zhang Jin-Xin; Guo Bao-Long; Wu Xian-Xiang; He Chao-Hui; Li Pei; Guo Hong-Xia

    2017-01-01

    The fabrication process dependent effects on single event effects (SEEs) are investigated in a commercial silicon–germanium heterojunction bipolar transistor (SiGe HBT) using three-dimensional (3D) TCAD simulations. The influences of device structure and doping concentration on SEEs are discussed via analysis of current transient and charge collection induced by ions strike. The results show that the SEEs representation of current transient is different from representation of the charge collection for the same process parameters. To be specific, the area of C/S junction is the key parameter that affects charge collection of SEE. Both current transient and charge collection are dependent on the doping of collector and substrate. The base doping slightly influences transient currents of base, emitter, and collector terminals. However, the SEEs of SiGe HBT are hardly affected by the doping of epitaxial base and the content of Ge. (paper)

  18. Fabrication and characterization of Bi2Sr2CaCu2O8+δ stacks by self-planarizing process

    International Nuclear Information System (INIS)

    Okanoue, K.; Ishida, H.; Funabiki, H.; Hamasaki, K.; Shimakage, N.; Kawakami, A.; Wang, Z.; Abe, H.

    2005-01-01

    We developed a new fabrication process of stacked intrinsic Josephson junctions using superconducting Bi 2 Sr 2 CaCu 2 O 8+δ (Bi-2212) single crystals. In the proposed self-planarizing process, the Bi-2212 crystal around the junction window was modified to insulator by soaking into the solution of dilute (0.05-0.2%) hydrochloric acid for 5 s. Energy dispersive X-ray (EDX) spectroscopy revealed that the acid-treated Bi-2212 exhibited the decrease of Cu and Sr contents in the crystals. The current-voltage characteristic of the stacks showed distinct resistive branches with large hysteresis at 77 K. The number of intrinsic junctions in the stacks linearly decreased with decreasing the concentration of the solution. The well controllability of the number of junctions in the self-planarized stacks may be useful for electronic device applications

  19. Strength of PLA Components Fabricated with Fused Deposition Technology Using a Desktop 3D Printer as a Function of Geometrical Parameters of the Process

    Directory of Open Access Journals (Sweden)

    Vladimir E. Kuznetsov

    2018-03-01

    Full Text Available The current paper studies the influence of geometrical parameters of the fused deposition modeling (FDM—fused filament fabrication (FFF 3D printing process on printed part strength for open source desktop 3D printers and the most popular material used for that purpose—i.e., polylactic acid (PLA. The study was conducted using a set of different nozzles (0.4, 0.6, and 0.8 mm and a range of layer heights from the minimum to maximum physical limits of the machine. To assess print strength, a novel assessment method is proposed. A tubular sample is loaded in the weakest direction (across layers in a three-point bending fixture. Mesostructure evaluation through scanning electronic microscopy (SEM scans of the samples was used to explain the obtained results. We detected a significant influence of geometric process parameters on sample mesostructure, and consequently, on sample strength.

  20. Cost-Benefit of the energy saving in the bioclimatic designs; Costo-Beneficio del ahorro de energia en los disenos bioclimaticos

    Energy Technology Data Exchange (ETDEWEB)

    Lopez P, J. Manuel A. [Doble Dos Soluciones de Negocios, S.A. de C.V., Mexico, D.F. (Mexico); Morillon G, David; Rodriguez V, Luis [Instituto de Ingenieria de la UNAM, Mexico, D.F. (Mexico)

    1999-07-01

    Tools and criteria for the Cost-Benefit analysis from the energy saving in bioclimatic designs (BD) are presented, for which, a reference project is established and the costs and benefits of energy saving in BD with base in that project are evaluated. A case study is presented taking as reference the traditional design of the air conditioning of a building and with this base the estimation of cost-benefit of the same building is made, but with passive systems. The tools used are those that allow to consider related resources such as time and money; in that sense, are used criteria such as: Present value (PV), Equivalent Annual Cost (EAC) and the Cost of the Conserved Energy (CCE). The costs related to the construction, maintenance and operation of the design are taken into account. The differences between the reference design and the BD, established from the application of these criteria, allow to evaluate the economic margin of the BD as far as operation and maintenance is concerned. Finally the CCE of the bioclimatic measures is evaluated as an initiative of energy saving and the present value is calculated of the energy saving in the entire useful life of a bioclimatic design. [Spanish] Se presentan herramientas y criterios para el analisis Costo-Beneficio del ahorro de energia en disenos bioclimaticos (DB), para lo cual, se establece un proyecto de referencia y se evaluan los costos y beneficios del ahorro de energia en DB con base en ese proyecto. Se presenta el estudio de un caso tomando como referencia el dise tradicional de la climatizacion de un edificio y con base en este, se realiza la estimacion de costos y beneficios del mismo edificio, pero con sistemas pasivos. Las herramientas usadas, son aquellas que permiten considerar recursos relacionados como son tiempo y dinero; en ese sentido, se usan criterios como: Valor Presente (VP), Costo Anual Equivalente (CAE) y el Costo de la Energia Conservada (CEC). Se toman en consideracion los costos relacionados