WorldWideScience

Sample records for surface micromachining batch

  1. Stiction in surface micromachining

    NARCIS (Netherlands)

    Tas, Niels Roelof; Sonnenberg, A.H.; Jansen, Henricus V.; Legtenberg, R.; Legtenberg, Rob; Elwenspoek, Michael Curt

    1996-01-01

    Due to the smoothness of the surfaces in surface micromachining, large adhesion forces between fabricated structures and the substrate are encountered. Four major adhesion mechanisms have been analysed: capillary forces, hydrogen bridging, electrostatic forces and van der Waals forces. Once contact

  2. Integrated mold/surface-micromachining process

    Energy Technology Data Exchange (ETDEWEB)

    Barron, C.C.; Fleming, J.G.; Montague, S.; Sniegowski, J.J.; Hetherington, D.L.

    1996-03-01

    We detail a new monolithically integrated silicon mold/surface-micromachining process which makes possible the fabrication of stiff, high-aspect-ratio micromachined structures integrated with finely detailed, compliant structures. An important example, which we use here as our process demonstration vehicle, is that of an accelerometer with a large proof mass and compliant suspension. The proof mass is formed by etching a mold into the silicon substrate, lining the mold with oxide, filling it with mechanical polysilicon, and then planarizing back to the level of the substrate. The resulting molded structure is recessed into the substrate, forming a planar surface ideal for subsequent processing. We then add surface-micromachined springs and sense contacts. The principal advantage of this new monolithically integrated mold/surface-micromachining process is that it decouples the design of the different sections of the device: In the case of a sensitive accelerometer, it allows us to optimize independently the proof mass, which needs to be as large, stiff, and heavy as possible, and the suspension, which needs to be as delicate and compliant as possible. 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. We 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.

  3. Enhancing cavitation with micromachined surfaces

    Science.gov (United States)

    Fernandez Rivas, David; Stricker, Laura; Zijlstra, Aaldert G.; Gardeniers, Han; Lohse, Detlef; Prosperetti, Andrea; Mesoscale Chemical System Group Collaboration; Physics of Fluids Group Collaboration; Department of Mechanical Engineering Collaboration

    2012-11-01

    When a silicon surface with micromachined pits submerged in a liquid is exposed to continuous ultrasound at 200 kHz, bubbles are ejected from the air filled cavities. Depending on the pressure amplitude different scenarios are observed, as the bubbles ejected from the micropits interact in complex ways with each other, and with the silicon surface. We have determined the size distribution of bubbles ejected from one, two and three pits for three different electrical power settings, and correlated them with sonochemical OH* radical production. Numerical simulations of the sonochemical conversion reaction rates were obtained using the empirical bubble size distributions and are compared with experimental results. Experimental evidence of shock wave emission from the microbubble clusters, deformed microbubble shapes, jetting and surface erosion are also presented. Financially supported through the project 07391 of the Technology Foundation STW, The Netherlands.

  4. Tribological issues of polysilicon surface-micromachining

    Energy Technology Data Exchange (ETDEWEB)

    Sniegowski, J.J.

    1997-12-01

    Polysilicon surface-micromachining is a Micro-Electro-Mechanical Systems (MEMS) manufacturing technology where the infrastructure for manufacturing silicon integrated circuits is used to fabricate micro-miniature mechanical devices. This presentation describes a multi-level mechanical polysilicon surface-micromachining technology and includes a discussion of the issues which affect device manufacture and performance. The multi-level technology was developed and is employed primarily to fabricate microactuated mechanisms. The intricate and complex motion offered by these devices is naturally accompanied by various forms of fraction and wear in addition to the classical stiction phenomena associated with micromechanical device fabrication and usage.

  5. A batch process micromachined thermoelectric energy harvester: Fabrication and characterization

    NARCIS (Netherlands)

    Su, J.; Leonov, V.; Goedbloed, M.; Andel, Y. van; Nooijer, M.C.de; Elfrink, R.; Wang, Z.; Vullers, R.J.M.

    2010-01-01

    Micromachined thermopiles are considered as a cost-effective solution for energy harvesters working at a small temperature difference and weak heat flows typical for, e.g., the human body. They can be used for powering autonomous wireless sensor nodes in a body area network. In this paper, a

  6. Manufacturing microsystems-on-a-chip with 5-level surface micromachining technology

    Energy Technology Data Exchange (ETDEWEB)

    Sniegowski, J.; Rodgers, M.S.

    1998-05-01

    An agile microsystem manufacturing technology has been developed that provides unprecedented 5 levels of independent polysilicon surface-micromachine films for the designer. Typical surface-micromachining processes offer a maximum of 3 levels, making this the most complex surface-micromachining process technology developed to date. Leveraged from the extensive infrastructure present in the microelectronics industry, the manufacturing method of polysilicon surface-micromachining offers similar advantages of high-volume, high-reliability, and batch-fabrication to microelectromechanical systems (MEMS) as has been accomplished with integrated circuits (ICs). These systems, comprised of microscopic-sized mechanical elements, are laying the foundation for a rapidly expanding, multi-billion dollar industry 2 which impacts the automotive, consumer product, and medical industries to name only a few.

  7. Batch fabrication of scanning microscopy probes for thermal and magnetic imaging using standard micromachining

    NARCIS (Netherlands)

    Sarajlic, Edin; Vermeer, Rolf; Delalande, M.Y.; Siekman, Martin Herman; Huijink, R.; Fujita, H.; Abelmann, Leon

    2010-01-01

    We present a process for batch fabrication of a novel scanning microscopy probe for thermal and magnetic imaging using standard micromachining and conventional optical contact lithography. The probe features an AFM-type cantilever with a sharp pyramidal tip composed of four freestanding silicon

  8. Design of Surface Micromachined Compliant MEMS

    Energy Technology Data Exchange (ETDEWEB)

    Bradley, Joe Anthony [Iowa State Univ., Ames, IA (United States)

    2002-12-31

    The consideration of compliant mechanisms as Microelectromechanical Systems (MEMS) is the focus of this research endeavor. MEMS are micron to millimeter devices that combine electrical, mechanical, and information processing capabilities on the same device. These MEMS need some mechanical motion or parts that move relative to each other. This relative motion, using multiple parts, is not desired because of the assembly requirement and the friction introduced. Compliant devices limits or eliminates friction and the need for multi-component assembly. Compliant devices improve designs by creating single piece mechanisms. The purpose of this research is to validate surface micromachining as a viable fabrication process for compliant MEMS designs. Specifically, this research has sought to fabricate a micro-compliant gripper and a micro-compliant clamp to illustrate the process. While other researchers have created compliant MEMs, most have used comb-drive actuation methods and bulk micromachining processes. This research focused on fully-compliant devices that use device flexibility for motion and actuation. Validation of these compliant MEMS is achieved by structural optimization of device design and functional performance testing. This research contributes to the ongoing research in MEMS by evaluating the potential of using surface micromachining as a process for fabricating compliant micro-mechanisms.

  9. Design of Surface micromachined Compliant MEMS

    Energy Technology Data Exchange (ETDEWEB)

    Bradley, Joe Anthony [Iowa State Univ., Ames, IA (United States)

    2001-01-01

    The consideration of compliant mechanisms as Microelectromechanical Systems (MEMS) is the focus of this research endeavor. MEMS are micron to millimeter devices that combine electrical, mechanical, and information processing capabilities on the same device. These MEMS need some mechanical motion or parts that move relative to each other. This relative motion, using multiple parts, is not desired because of the assembly requirement and the friction introduced. Compliant devices limits or eliminates friction and the need for multi-component assembly. Compliant devices improve designs by creating single piece mechanisms. The purpose of this research is to validate surface micromachining as a viable fabrication process for compliant MEMS designs. Specifically, this research has sought to fabricate a micro-compliant gripper and a micro-compliant clamp to illustrate the process. While other researchers have created compliant MEMS, most have used comb-drive actuation methods and bulk micromachining processes. This research focuses on fully-compliant devices that use device flexibility for motion and actuation. Validation of these compliant MEMS is achieved by structural optimization of device design and functional performance testing. This research contributes to the ongoing research in MEMS by evaluating the potential of using surface micromachining as a process for fabricating compliant micro-mechanisms.

  10. Surface Micromachined Arrays of Transition-Edge Detectors, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — An innovative surface micromachining technique is described for the fabrication of closely-packed arrays of transition edge sensor (TES) x-ray microcalorimeters....

  11. Multi-layer enhancement to polysilicon surface-micromachining technology

    Energy Technology Data Exchange (ETDEWEB)

    Sniegowski, J.J.; Rodgers, M.S. [Sandia National Labs., Albuquerque, NM (United States). Intelligent Micromachine Dept.

    1997-10-01

    A multi-level polysilicon surface-micromachining technology consisting of 5 layers of polysilicon is presented. Surface topography and film mechanical stress are the major impediments encountered in the development of a multilayer surface-micromachining process. However, excellent mechanical film characteristics have been obtained through the use of chemical-mechanical polishing for planarization of topography and by proper sequencing of film deposition with thermal anneals. Examples of operating microactuators, geared power-transfer mechanisms, and optical elements demonstrate the mechanical advantages of construction with 5 polysilicon layers.

  12. Condensation of sodium on a micromachined surface for AMTEC

    International Nuclear Information System (INIS)

    Crowley, C.J.; Izenson, M.G.

    1993-01-01

    A novel condenser component is being developed to enable Alkali Metal Thermal to Electric Conversion (AMTEC) technology to achieve two critical goals: (1) optimization of conversion efficiency and (2) microgravity fluid management. The first goal is achieved by minimizing parasitic radiation heat transfer losses for condensers with a large view factor to the high-temperature β double-prime-alumina surface. The condenser geometry includes a specially designed, micromachined surface where large capillary forces are used to manage the fluid distribution to accomplish the second goal. We present and discuss the results of separate effects experiments investigating the wetting and condensation behavior of sodium on this capillary surface. Test results show that the micromachined surface maintains a smooth, high reflective film of liquid sodium on the surface, which implies reduced parasitic losses and increased conversion efficiencies in AMTEC cells. Accomplishing this in an adverse gravity gradient demonstrates the potential for management of the fluid even under spacecraft acceleration conditions

  13. Surface micromachined counter-meshing gears discrimination device

    International Nuclear Information System (INIS)

    Polosky, M.A.; Garcia, E.J.; Allen, J.J.

    1998-01-01

    This paper discusses the design, fabrication and testing of a surface micromachined Counter-Meshing Gears (CMG) discrimination device which functions as a mechanically coded lock, A 24 bit code is input to unlock the device. Once unlocked, the device provides a path for an energy or information signal to pass through the device. The device is designed to immediately lock up if any portion of the 24 bit code is incorrect. The motivation for the development of this device is based on occurrences referred to as High Consequence Events, A High Consequence Event is an event where an inadvertent operation of a system could result in the catastrophic loss of life, property, or damage to the environment

  14. Macrodesign for microdevices: Polysilicon surface-micromachining technology, applications and issues

    Energy Technology Data Exchange (ETDEWEB)

    Sniegowski, J.J. [Sandia National Labs., Albuquerque, NM (United States). Intelligent Micromachine Dept.

    1997-05-01

    The intent of this tutorial is to overview the technology of multi-level polysilicon surface micromachining, to present examples of devices which fully utilize this level of complexity, and to discuss what they believe to be significant issues which are not fully resolved. Following this intent, the tutorial consists of four sections. The first is an introduction and description of multi-level polysilicon surface micromachining and its potential benefits. Specifically, the inclusion of a third deposited layer of mechanical polysilicon greatly extends the degree of complexity available for micromechanism design. The second section introduces wafer planarization by CMP as a process tool for surface micromachining. The third section presents examples of actuated geared micromechanisms which require the multi-level fabrication process. Demonstration of actuation mechanisms coupled to external devices are illustrated. Finally, polysilicon surface micromachining fabrication technology has reached a level where many device designs, for the most part, can be embodied in the technology to produce a mechanical construct which provides the desired function. When designed properly, the fabricated mechanical element, if free to operate, will produce the desired function. However, one set of issues which can hinder or prevent operation are related to the post-fabricated device surfaces. These surface issues; namely, stiction, friction, and wear, are emphasized in the final section as a major hindrance to realizing the full potential of surface micromachined devices.

  15. Optical micro-metrology of structured surfaces micro-machined by jet-ECM

    DEFF Research Database (Denmark)

    Quagliotti, Danilo; Tosello, Guido; Islam, Aminul

    2015-01-01

    A procedure for statistical analysis and uncertainty evaluation is presented with regards to measurements of step height and surface texture. Measurements have been performed with a focus-variation microscope over jet electrochemical micro-machined surfaces. Traceability has been achieved using...

  16. First reliability test of a surface micromachined microengine using SHiMMeR

    Energy Technology Data Exchange (ETDEWEB)

    Tanner, D.M.; Smith, N.F.; Bowman, D.J. [and others

    1997-08-01

    The first-ever reliability stress test on surface micromachined microengines developed at Sandia National Laboratories (SNL) has been completed. We stressed 41 microengines at 36,000 RPM and inspected the functionality at 60 RPM. We have observed an infant mortality region, a region of low failure rate (useful life), and no signs of wearout in the data. The reliability data are presented and interpreted using standard reliability methods. Failure analysis results on the stressed microengines are presented. In our effort to study the reliability of MEMS, we need to observe the failures of large numbers of parts to determine the failure modes. To facilitate testing of large numbers of micromachines. The Sandia High Volume Measurement of Micromachine Reliability (SHiMMeR) system has computer controlled positioning and the capability to inspect moving parts. The development of this parallel testing system is discussed in detail.

  17. Fabrication of surface micromachined ain piezoelectric microstructures and its potential apllication to rf resonators

    NARCIS (Netherlands)

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

    2005-01-01

    We report on a novel microfabrication method to fabricate aluminum nitride (AlN) piezoelectric microstructures down to 2 microns size by a surface micromachining process. Highly c-axis oriented AlN thin films are deposited between thin Cr electrodes on polysilicon structural layers by rf reactive

  18. Surface micromachined fabrication of piezoelectric ain unimorph suspension devices for rf resonator applications

    NARCIS (Netherlands)

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

    We report a surface micromachining process for aluminum nitride (AlN) thin films to fabricate piezoelectric unimorph suspension devices for actuator applications. Polysilicon is used as a structural layer. Highly c-axis oriented AlN thin films 1 /spl mu/m thick are deposited by rf reactive

  19. A manufacturing method for multi-layer polysilicon surface-micromachining technology

    Energy Technology Data Exchange (ETDEWEB)

    Sniegowski, J.J.; Rodgers, M.S.

    1998-01-01

    An advanced manufacturing technology which provides multi-layered polysilicon surface micromachining technology for advanced weapon systems is presented. Specifically, the addition of another design layer to a 4 levels process to create a 5 levels process allows consideration of fundamentally new architecture in designs for weapon advanced surety components.

  20. Thermal simulation of surface micromachined polysilicon hot plates of low power consumption

    NARCIS (Netherlands)

    Dumitrescu, Marius; Cobianu, Cornel; Lungu, Dan; Pascu, Adrian; Kolev, Spas; van den Berg, Albert

    1999-01-01

    A simple, IC compatible, surface micromachined polysilicon membrane was technologically designed and thermally simulated by 3D finite element ‘COSMOS' program in order to investigate its capability to work as a micro hot plate for a gas sensing test structure of low power consumption. For an

  1. Effect of fluorocarbon self-assembled monolayer films on sidewall adhesion and friction of surface micromachines with impacting and sliding contact interfaces

    International Nuclear Information System (INIS)

    Xiang, H.; Komvopoulos, K.

    2013-01-01

    A self-assembled monolayer film consisting of fluoro-octyltrichlorosilane (FOTS) was vapor-phase deposited on Si(100) substrates and polycrystalline silicon (polysilicon) surface micromachines. The hydrophobic behavior and structural composition of the FOTS film deposited on Si(100) were investigated by goniometry and X-ray photoelectron spectroscopy, respectively. The effects of contact pressure, relative humidity, temperature, and impact/sliding cycles on the adhesive and friction behavior of uncoated and FOTS-coated polysilicon micromachines (referred to as the Si and FOTS/Si micromachines, respectively) were investigated under controlled loading and environmental conditions. FOTS/Si micromachines demonstrated much lower and stable adhesion than Si micromachines due to the highly hydrophobic and conformal FOTS film. Contrary to Si micromachines, sidewall adhesion of FOTS/Si micromachines demonstrated a weak dependence on relative humidity, temperature, and impact cycles. In addition, FOTS/Si micromachines showed low and stable adhesion and low static friction for significantly more sliding cycles than Si micromachines. The adhesive and static friction characteristics of Si and FOTS/Si micromachines are interpreted in the context of physicochemical surface changes, resulting in the increase of the real area of contact and a hydrophobic-to-hydrophilic transition of the surface chemical characteristics caused by nanoscale surface smoothening and the removal of the organic residue (Si micromachines) or the FOTS film (FOTS/Si micromachines) during repetitive impact and oscillatory sliding of the sidewall surfaces.

  2. Enhancing structural integrity of adhesive bonds through pulsed laser surface micro-machining

    KAUST Repository

    Diaz, Edwin Hernandez

    2015-06-01

    Enhancing the effective peel resistance of plastically deforming adhesive joints through laser-based surface micro-machining Edwin Hernandez Diaz Inspired by adhesion examples commonly found in nature, we reached out to examine the effect of different kinds of heterogeneous surface properties that may replicate this behavior and the mechanisms at work. In order to do this, we used pulsed laser ablation on copper substrates (CuZn40) aiming to increase adhesion for bonding. A Yb-fiber laser was used for surface preparation of the substrates, which were probed with a Scanning Electron Microscope (SEM) and X-ray Photoelectron Spectroscopy (XPS). Heterogeneous surface properties were devised through the use of simplified laser micromachined patterns which may induce sequential events of crack arrest propagation, thereby having a leveraging effect on dissipation. The me- chanical performance of copper/epoxy joints with homogeneous and heterogeneous laser micromachined interfaces was then analyzed using the T-peel test. Fractured surfaces were analyzed using SEM to resolve the mechanism of failure and adhesive penetration within induced surface asperities from the treatment. Results confirm positive modifications of the surface morphology and chemistry from laser ablation that enable mechanical interlocking and cohesive failure within the adhesive layer. Remarkable improvements of apparent peel energy, bond toughness, and effective peel force were appreciated with respect to sanded substrates as control samples.

  3. Micromachined silicon seismic transducers

    Energy Technology Data Exchange (ETDEWEB)

    Barron, C.C.; Fleming, J.G.; Sniegowski, J.J.; Armour, D.L.; Fleming, R.P.

    1995-08-01

    Batch-fabricated silicon seismic transducers could revolutionize the discipline of CTBT monitoring by providing inexpensive, easily depolyable sensor arrays. Although our goal is to fabricate seismic sensors that provide the same performance level as the current state-of-the-art ``macro`` systems, if necessary one could deploy a larger number of these small sensors at closer proximity to the location being monitored in order to compensate for lower performance. We have chosen a modified pendulum design and are manufacturing prototypes in two different silicon micromachining fabrication technologies. The first set of prototypes, fabricated in our advanced surface- micromachining technology, are currently being packaged for testing in servo circuits -- we anticipate that these devices, which have masses in the 1--10 {mu}g range, will resolve sub-mG signals. Concurrently, we are developing a novel ``mold`` micromachining technology that promises to make proof masses in the 1--10 mg range possible -- our calculations indicate that devices made in this new technology will resolve down to at least sub-{mu}G signals, and may even approach to 10{sup {minus}10} G/{radical}Hz acceleration levels found in the low-earth-noise model.

  4. Development of a Surface Micromachined On-Chip Flat Disk Micropump

    Directory of Open Access Journals (Sweden)

    M. I. KILANI

    2009-08-01

    Full Text Available The paper presents research progress in the development of a surface micromachined flat disk micropump which employs the viscous and centrifugal effects acting on a layer of fluid sandwiched between a rotating flat disk and a stationary plate. The pump is fabricated monolithically on-chip using Sandia’s Ultraplanar Multilevel MEMS Technology (SUMMiT™ where an electrostatic comb-drive Torsional Ratcheting Actuator (TRA drives the flat disk through a geared transmission. The paper reviews available analytical models for flow geometries similar to that of the described pump, and presents a set of experiments which depict its performance and possible failure modes. Those experiments highlight future research directions in the development of electrostatically-actuated, CMOS-compatible, surface micromachined pumps.

  5. A wafer mapping technique for residual stress in surface micromachined films

    International Nuclear Information System (INIS)

    Schiavone, G; Murray, J; Smith, S; Walton, A J; Desmulliez, M P Y; Mount, A R

    2016-01-01

    The design of MEMS devices employing movable structures is crucially dependant on the mechanical behaviour of the deposited materials. It is therefore important to be able to fully characterize the micromachined films and predict with confidence the mechanical properties of patterned structures. This paper presents a characterization technique that enables the residual stress in MEMS films to be mapped at the wafer level by using microstructures released by surface micromachining. These dedicated MEMS test structures and the associated measurement techniques are used to extract localized information on the strain and Young’s modulus of the film under investigation. The residual stress is then determined by numerically coupling this data with a finite element analysis of the structure. This paper illustrates the measurement routine and demonstrates it with a case study using electrochemically deposited alloys of nickel and iron, particularly prone to develop high levels of residual stress. The results show that the technique enables wafer mapping of film non-uniformities and identifies wafer-to-wafer differences. A comparison between the results obtained from the mapping technique and conventional wafer bow measurements highlights the benefits of using a procedure tailored to films that are non-uniform, patterned and surface-micromachined, as opposed to simple standard stress extraction methods. The presented technique reveals detailed information that is generally unexplored when using conventional stress extraction methods such as wafer bow measurements. (paper)

  6. Fibroblast adhesion and activation onto micro-machined titanium surfaces.

    Science.gov (United States)

    Guillem-Marti, J; Delgado, L; Godoy-Gallardo, M; Pegueroles, M; Herrero, M; Gil, F J

    2013-07-01

    Surface modifications performed at the neck of dental implants, in the manner of micro-grooved surfaces, can reduce fibrous tissue encapsulation and prevent bacterial colonization, thereby improving fibrointegration and the formation of a biological seal. However, the applied procedures are technically complex and/or time consuming methods. The aim of this study was to analyse the fibroblast behaviour on modified titanium surfaces obtained, applying a simple and low-cost method. An array of titanium surfaces was obtained using a commercial computerized numerical control lathe, modifying the feed rate and the cutting depth. To elucidate the potential ability of the generated surfaces to activate connective tissue cells, a thorough gene (by real time - qPCR) and protein (by western blot or zymography) expression and cellular response characterization (cell morphology, cell adhesion and cell activation by secreting extracellular matrix (ECM) components and their enzyme regulators) was performed. Micro-grooved surfaces have statistically significant differences in the groove's width (approximately 10, 50 and 100 μm) depending on the applied advancing fixed speed. Field emission scanning electron microscopy images showed that fibroblasts oriented along the generated grooves, but they were only entirely accommodated on the wider grooves (≥50 μm). Micro-grooved surfaces exhibited an earlier cell attachment and activation, as seen by collagen Iα1 and fibronectin deposition and activation of ECM remodelling enzymes, compared with the other surfaces. However, fibroblasts could remain in an activated state on narrower surfaces (micro-grooved surfaces could improve implant integration at the gingival site with respect to polished surfaces. Micro-grooved surfaces enhance early fibroblast adhesion and activation, which could be critical for the formation of a biological seal and finally promote tissue integration. Surfaces with wider grooves (≥50 μm) seem to be more

  7. Effects of Micromachining Processes on Electro-Osmotic Flow Mobility of Glass Surfaces

    Directory of Open Access Journals (Sweden)

    Norihisa Miki

    2013-03-01

    Full Text Available Silica glass is frequently used as a device material for micro/nano fluidic devices due to its excellent properties, such as transparency and chemical resistance. Wet etching by hydrofluoric acid and dry etching by neutral loop discharge (NLD plasma etching are currently used to micromachine glass to form micro/nano fluidic channels. Electro-osmotic flow (EOF is one of the most effective methods to drive liquids into the channels. EOF mobility is affected by a property of the micromachined glass surfaces, which includes surface roughness that is determined by the manufacturing processes. In this paper, we investigate the effect of micromaching processes on the glass surface topography and the EOF mobility. We prepared glass surfaces by either wet etching or by NLD plasma etching, investigated the surface topography using atomic force microscopy, and attempted to correlate it with EOF generated in the micro-channels of the machined glass. Experiments revealed that the EOF mobility strongly depends on the surface roughness, and therefore upon the fabrication process used. A particularly strong dependency was observed when the surface roughness was on the order of the electric double layer thickness or below. We believe that the correlation described in this paper can be of great help in the design of micro/nano fluidic devices.

  8. A novel hybrid surface micromachined segmented mirror for large aperture laser applications

    Science.gov (United States)

    Li, Jie; Chen, Haiqing; Yu, Hongbin

    2006-07-01

    A novel hybrid surface micromachined segmented mirror array is described. This device is capable of scaling to large apertures for correcting time-varying aberrations in laser applications. Each mirror is composed of bottom electrode, support part, and mirror plate, in which a T-shaped beam structure is used to support the mirror plate. It can provide mirror with vertical movement and rotation around two horizontal axes. The test results show that the maximum deflection along the vertical direction of the mirror plate is 2 microns, while the rotation angles around x and y axes are +-2.3 deg. and +-1.45 deg., respectively.

  9. Micromachined silicon seismic accelerometer development

    Energy Technology Data Exchange (ETDEWEB)

    Barron, C.C.; Fleming, J.G.; Montague, S. [and others

    1996-08-01

    Batch-fabricated silicon seismic transducers could revolutionize the discipline of seismic monitoring by providing inexpensive, easily deployable sensor arrays. Our ultimate goal is to fabricate seismic sensors with sensitivity and noise performance comparable to short-period seismometers in common use. We expect several phases of development will be required to accomplish that level of performance. Traditional silicon micromachining techniques are not ideally suited to the simultaneous fabrication of a large proof mass and soft suspension, such as one needs to achieve the extreme sensitivities required for seismic measurements. We have therefore developed a novel {open_quotes}mold{close_quotes} micromachining technology that promises to make larger proof masses (in the 1-10 mg range) possible. We have successfully integrated this micromolding capability with our surface-micromachining process, which enables the formation of soft suspension springs. Our calculations indicate that devices made in this new integrated technology will resolve down to at least sub-{mu}G signals, and may even approach the 10{sup -10} G/{radical}Hz acceleration levels found in the low-earth-noise model.

  10. 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

  11. Dependence of capillary forces on relative humidity and the surface properties of femtosecond laser micromachined titanium.

    Science.gov (United States)

    Lehr, Jorge; Kietzig, Anne-Marie

    2015-06-15

    Capillary forces were measured with colloidal atomic force microscopy at different levels of relative humidity on femtosecond laser micromachined titanium surfaces. After laser machining at different intensity levels, the titanium surfaces show a nanoscale ripple topology or microscopic bumpy structures. Different machining environments were chosen to influence the surface chemistry in addition to topology: while machining in pure oxygen and water resulted in surfaces consisting of TiO2, a composite surface of TiO2 and TiN was obtained after machining in pure nitrogen. All samples were subsequently exposed to pure oxygen, carbon dioxide or water, and showed different levels of wettability and capillary force. We have introduced the concept of humidity sensitivity as the relative increase of the capillary force with respect to the measured force at 0% humidity. We report that samples with a nanoscale ripple topology machined in pure oxygen exhibit the lowest level of capillary force and the lowest sensitivity towards humidity in the environment. Surfaces with low sensitivity towards changes of the relative humidity are good candidates for technical applications, where capillary forces have to be controlled. This study contributes to the development of such surfaces, to a better understanding of how capillary bridges are formed on rough surfaces and ultimately to the exploration of the relationship between surface wettability and capillary forces. Copyright © 2015 Elsevier Inc. All rights reserved.

  12. The Development of Micromachined Gyroscope Structure and Circuitry Technology

    OpenAIRE

    Dunzhu Xia; Cheng Yu; Lun Kong

    2014-01-01

    This review surveys micromachined gyroscope structure and circuitry technology. The principle of micromachined gyroscopes is first introduced. Then, different kinds of MEMS gyroscope structures, materials and fabrication technologies are illustrated. Micromachined gyroscopes are mainly categorized into micromachined vibrating gyroscopes (MVGs), piezoelectric vibrating gyroscopes (PVGs), surface acoustic wave (SAW) gyroscopes, bulk acoustic wave (BAW) gyroscopes, micromachined electrostati...

  13. The Effect of Humidity on the Reliability of a Surface Micromachined Microengine

    Energy Technology Data Exchange (ETDEWEB)

    Dugger, M.T.; Eaton, W.P.; Irwin, L.W.; Miller, S.L.; Miller, W.M.; Smith, N.F.; Tanner, D.M.; Walraven, J.A.

    1999-02-02

    Humidity is shown to be a strong factor in the wear of rubbing surfaces in polysilicon micromachines. We demonstrate that very low humidity can lead to very high wear without a significant change in reliability. We show that the volume of wear debris generated is a function of the humidity in an air environment. As the humidity decreases, the wear debris generated increases. For the higher humidity levels, the formation of surface hydroxides may act as a lubricant. The dominant failure mechanism has been identified as wear. The wear debris has been identified as amorphous oxidized silicon. Large slivers (approximately 1 micron in length) of debris observed at the low humidity level were also amorphous oxidized silicon. Using transmission electron microscopy, we observed that the wear debris forms spherical and rod-like shapes. We compared two surface treatment processes: a fluorinated si- lane chain, (FITl) and supercritical C02 dried (SCC02). The microengines using the SCC02 process were found to be less reliable than those released with the FIX process under two humidity levels.

  14. Linkage design effect on the reliability of surface micromachined microengines driving a load

    Energy Technology Data Exchange (ETDEWEB)

    Tanner, D.M.; Peterson, K.A.; Irwin, L.W.; Tangyunyong, P.; Miller, W.M.; Eaton, W.P.; Smith, N.F.; Rodgers, M.S.

    1998-08-01

    The reliability of microengines is a function of the design of the mechanical linkage used to connect the electrostatic actuator to the drive. The authors have completed a series of reliability stress tests on surface micromachined microengines driving an inertial load. In these experiments, the authors used microengines that had pin mechanisms with guides connecting the drive arms to the electrostatic actuators. Comparing this data to previous results using flexure linkages revealed that the pin linkage design was less reliable. The devices were stressed to failure at eight frequencies, both above and below the measured resonance frequency of the microengine. Significant amounts of wear debris were observed both around the hub and pin joint of the drive gear. Additionally, wear tracks were observed in the area where the moving shuttle rubbed against the guides of the pin linkage. At each frequency, they analyzed the statistical data yielding a lifetime (t{sub 50}) for median cycles to failure and {sigma}, the shape parameter of the distribution. A model was developed to describe the failure data based on fundamental wear mechanisms and forces exhibited in mechanical resonant systems. The comparison to the model will be discussed.

  15. Surface Micromachining Process for the Integration of AlN Piezoelectric Microstructures

    NARCIS (Netherlands)

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

    2004-01-01

    We report a novel micromachining process to fabricate AlN (Aluminum Nitride) piezoelectric microstructures for actuator applications. Piezoelectric AlN thin films can be grown with (002) preferential orientation by means of RF reactive sputtering on various substrates. For this study, AlN was

  16. Inhibition of Sulfide Mineral Oxidation by Surface Coating Agents: Batch

    Science.gov (United States)

    Choi, J.; Ji, M. K.; Yun, H. S.; Park, Y. T.; Gee, E. D.; Lee, W. R.; Jeon, B.-H.

    2012-04-01

    Mining activities and mineral industries have impacted on rapid oxidation of sulfide minerals such as pyrite (FeS2) which leads to Acid Mine Drainage (AMD) formation. Some of the abandoned mines discharge polluted water without proper environmental remediation treatments, largely because of financial constraints in treating AMD. Magnitude of the problem is considerable, especially in countries with a long history of mining. As metal sulfides become oxidized during mining activities, the aqueous environment becomes acid and rich in many metals, including iron, lead, mercury, arsenic and many others. The toxic heavy metals are responsible for the environmental deterioration of stream, groundwater and soils. Several strategies to remediate AMD contaminated sites have been proposed. Among the source inhibition and prevention technologies, microencapsulation (coating) has been considered as a promising technology. The encapsulation is based on inhibition of O2 diffusion by surface coating agent and is expected to control the oxidation of pyrite for a long time. Potential of several surface coating agents for preventing oxidation of metal sulfide minerals from both Young-Dong coal mine and Il-Gwang gold mine were examined by conducting batch experiments and field tests. Powdered pyrite as a standard sulfide mineral and rock samples from two mine outcrops were mixed with six coating agents (KH2PO4, MgO and KMnO4 as chemical agents, and apatite, cement and manganite as mineral agents) and incubated with oxidizing agents (H2O2 or NaClO). Batch experiments with Young-Dong coal mine samples showed least SO42- production in presence of KMnO4 (16% sulfate production compared to no surface coating agents) or cement (4%) within 8 days. In the case of Il-Gwang mine samples, least SO42- production was observed in presence of KH2PO4 (8%) or cement (2%) within 8 days. Field-scale pilot tests at Il-Gwang site also showed that addition of KH2PO4 decreased sulfate production from 200 to

  17. Micro-machining.

    Science.gov (United States)

    Brinksmeier, Ekkard; Preuss, Werner

    2012-08-28

    Manipulating bulk material at the atomic level is considered to be the domain of physics, chemistry and nanotechnology. However, precision engineering, especially micro-machining, has become a powerful tool for controlling the surface properties and sub-surface integrity of the optical, electronic and mechanical functional parts in a regime where continuum mechanics is left behind and the quantum nature of matter comes into play. The surprising subtlety of micro-machining results from the extraordinary precision of tools, machines and controls expanding into the nanometre range-a hundred times more precise than the wavelength of light. In this paper, we will outline the development of precision engineering, highlight modern achievements of ultra-precision machining and discuss the necessity of a deeper physical understanding of micro-machining.

  18. Safety and security monitoring of dams using nano-micromachined-based surface acoustic wave (SAW) sensors

    Science.gov (United States)

    Ross, Wayne, Jr.; Saafi, Mohamed; Romine, Peter; Xiao, Zhigang; Pett, Dave

    2006-03-01

    Concerns about the safety of concrete dams have increased during recent years, partly because the population at risk in locations downstream of major dams continues to expand and also because these old dams are experiencing long-term damage and the seismic design concepts used to build them were inadequate. Reliable techniques for continuous monitoring of certain key parameters affecting the dams' integrity are currently nonexistent and this is because of the lack of sensing technology capable to function in a hostile environment such as low temperatures and high moisture level. This paper presents new low cost, passive and wireless micro-machined SAW-based sensors to monitor the safety and security of dams. These SAW sensors are composed of MEMS transducers, Nano-polymer actuators and an antenna, and are deposited on a thin film substrate. The sensors are passive, do not require power on-board and can be interrogated wireless using a radar. When embedded into concrete dams, the devices will be able to detect and locate internal cracks and measure certain key parameters affecting the durability of dams such as temperature, moisture, pH, chloride and carbon dioxide.

  19. A row-column addressed micromachined ultrasonic transducer array for surface scanning applications.

    Science.gov (United States)

    Wong, Lawrence L P; Chen, Albert I H; Li, Zhenhao; Logan, Andrew S; Yeow, John T W

    2014-12-01

    Row-column addressed arrays for ultrasonic non-destructive testing (NDT) applications are analyzed and demonstrated in this paper. Simulation and experimental results of a row-column addressed 32 by 32 capacitive micromachined ultrasonic transducer (CMUT) array are presented. The CMUT array, which was designed for medical imaging applications, has a center frequency of 5.3MHz. The CMUT array was used to perform C-scans on test objects with holes that have diameters of 1.0mm and 0.5mm. The array transducer has an aperture size of 4.8mm by 4.8mm, and it was used to scan an area of 4.0mm by 4.0mm. Compared to an N by N fully addressed 2-D array, a row-column addressed array of the same number of elements requires fewer (N instead of N(2)) pairs of interconnection and supporting electronic components such as pulsers and amplifiers. Even though the resulting field of view is limit by the aperture size, row-column addressed arrays and the row-column addressing scheme can be an alternative option of 2-D arrays for NDT applications. Copyright © 2014 Elsevier B.V. All rights reserved.

  20. Surface-micromachined magnetic undulator with period length between 10μm and 1 mm for advanced light sources

    Science.gov (United States)

    Harrison, Jere; Joshi, Abhijeet; Lake, Jonathan; Candler, Rob; Musumeci, Pietro

    2012-07-01

    A technological gap exists between the μm-scale wiggling periods achieved using electromagnetic waves of high intensity laser pulses and the mm scale of permanent-magnet and superconducting undulators. In the sub-mm range, surface-micromachined soft-magnetic micro-electro-mechanical system inductors with integrated solenoidal coils have already experimentally demonstrated 100 to 500 mT field amplitude across air gaps as large as 15μm. Simulations indicate that magnetic fields as large as 1.5 T across 50μm inductor gaps are feasible. A simple rearranging of the yoke and pole geometry allows for fabrication of 10+ cm long undulator structures with period lengths between 12.5μm and 1 mm. Such undulators find application both in high average power spontaneous emission sources and, if used in combination with ultrahigh-brightness electron beams, could lead to the realization of low energy compact free-electron lasers. Challenges include electron energy broadening due to wakefields and Joule heating in the electromagnet.

  1. Surface-Micromachined Neural Sensors with Integrated Double Side Recordings on Dry-Etch Benzocyclobutene(BCB) Substrate.

    Science.gov (United States)

    Zhu, Haixin; He, Jiping; Kim, Bruce

    2005-01-01

    a neural sensor with novel structure and capable of double side recordings has been designed and fabricated using surface micromachining technique. Dry-etch Benzocyclobutene (BCB) was selected as the substrate and packaging material for its excellent electrical, mechanical and thermal properties. Positive photoresist (AZ4620) was used as the sacrificial layer during the formation of backside recording sites, and the lift-off process combined with BCB dry etch technique was developed to open the recording sites on the backside. The finished device has intracortical recording sites on both sides, and also epidural recording sites on the front side. The total channel number doubled compared to that of single side electrode structure. Three dry-etch BCB layers were applied to insulate the front side conduction traces from the backside trace layer, and package the entire devices. The developed process shows reliable and high fabrication yield, and results suggest that this newly developed neural sensor could improve the performance and efficiency of neural recording.

  2. Optimization of micropipette fabrication by laser micromachining for application in an ultrafine atmospheric pressure plasma jet using response surface methodology

    International Nuclear Information System (INIS)

    Wang, Tao; Liu, Jingquan; Yang, Bin; Chen, Xiang; Wang, Xiaolin; Yang, Chunsheng

    2016-01-01

    The optimization of the laser micromachining process for special tapered micropipettes was investigated using response surface methodology. Three process parameters for the CO 2 laser-based micropipette puller (P-2000, Sutter Instrument) were chosen as variables, namely heat, velocity and pull. The targeted length L TVS of the tapered variant section with a tip diameter of 10 μ m was taken as a response. The optimum process parameters with L TVS of 7.3 mm were determined by analyzing the response surface three-dimension surface plots. The central composite design was selected to optimize the process variables, and the experimental data were fitted into a reduced cubic polynomial model. The high R 2 value (99.66%) and low coefficient of variation (0.73%) indicated the statistical significance of the model and good precision for the experiment. The optimization result showed that the best parameters were with the heat, velocity and pull values of 850, 53 and 170, respectively. The result was verified by a CO 2 laser-based micropipette puller three times with length L TVS at 7.26 mm, 7.35 mm and 7.36 mm with the same optimized parameters. Then, the application to the ultrafine atmospheric pressure He/O 2 plasma jets was carried out and micro-hole etching of the parylene-C film was realized with length L TVS at 6.29 mm, 7.35 mm and 8.02 mm. The results showed that the micro-plasma jet with an L TVS of 7.35 mm had the minimum applied voltage of 12.7 kV and the minimum micro-etching diameter of 45 μ m with the deepest etching depth of 2.8 μ m. (paper)

  3. Development of batch producible hot embossing 3D nanostructured surface-enhanced Raman scattering chip technology

    Science.gov (United States)

    Huang, Chu-Yu; Tsai, Ming-Shiuan

    2017-09-01

    The main purpose of this study is to develop a batch producible hot embossing 3D nanostructured surface-enhanced Raman chip technology for high sensitivity label-free plasticizer detection. This study utilizing the AAO self-assembled uniform nano-hemispherical array barrier layer as a template to create a durable nanostructured nickel mold. With the hot embossing technique and the durable nanostructured nickel mold, we are able to batch produce the 3D Nanostructured Surface-enhanced Raman Scattering Chip with consistent quality. In addition, because of our SERS chip can be fabricated by batch processing, the fabrication cost is low. Therefore, the developed method is very promising to be widespread and extensively used in rapid chemical and biomolecular detection applications.

  4. Surface Nano Structures Manufacture Using Batch Chemical Processing Methods for Tooling Applications

    DEFF Research Database (Denmark)

    Tosello, Guido; Calaon, Matteo; Gavillet, J.

    2011-01-01

    The patterning of large surface areas with nano structures by using chemical batch processes to avoid using highenergy intensive nano machining processes was investigated. The capability of different surface treatment methods of creating micro and nano structured adaptable mould inserts...... for subsequent polymer replication by injection moulding was analyzed. New tooling solutions to produce nano structured mould surfaces were investigated. Experiments based on three different chemical-based-batch techniques to establish surface nano (i.e. sub-μm) structures on large areas were performed. Three...... approaches were selected: (1) using Ø500 nm nano beads deposition for direct patterning of a 4” silicon wafer; (2) using Ø500 nm nano beads deposition as mask for 4” silicon wafer etching and subsequent nickel electroplating; (3) using the anodizing process to produce Ø500 nm structures on a 30x80 mm2...

  5. Surface micromachined MEMS deformable mirror based on hexagonal parallel-plate electrostatic actuator

    Science.gov (United States)

    Ma, Wenying; Ma, Changwei; Wang, Weimin

    2018-03-01

    Deformable mirrors (DM) based on microelectromechanical system (MEMS) technology are being applied in adaptive optics (AO) system for astronomical telescopes and human eyes more and more. In this paper a MEMS DM with hexagonal actuator is proposed and designed. The relationship between structural design and performance parameters, mainly actuator coupling, is analyzed carefully and calculated. The optimum value of actuator coupling is obtained. A 7-element DM prototype is fabricated using a commercial available standard three-layer polysilicon surface multi-user-MEMS-processes (PolyMUMPs). Some key performances, including surface figure and voltage-displacement curve, are measured through a 3D white light profiler. The measured performances are very consistent with the theoretical values. The proposed DM will benefit the miniaturization of AO systems and lower their cost.

  6. The development of micromachined gyroscope structure and circuitry technology.

    Science.gov (United States)

    Xia, Dunzhu; Yu, Cheng; Kong, Lun

    2014-01-14

    This review surveys micromachined gyroscope structure and circuitry technology. The principle of micromachined gyroscopes is first introduced. Then, different kinds of MEMS gyroscope structures, materials and fabrication technologies are illustrated. Micromachined gyroscopes are mainly categorized into micromachined vibrating gyroscopes (MVGs), piezoelectric vibrating gyroscopes (PVGs), surface acoustic wave (SAW) gyroscopes, bulk acoustic wave (BAW) gyroscopes, micromachined electrostatically suspended gyroscopes (MESGs), magnetically suspended gyroscopes (MSGs), micro fiber optic gyroscopes (MFOGs), micro fluid gyroscopes (MFGs), micro atom gyroscopes (MAGs), and special micromachined gyroscopes. Next, the control electronics of micromachined gyroscopes are analyzed. The control circuits are categorized into typical circuitry and special circuitry technologies. The typical circuitry technologies include typical analog circuitry and digital circuitry, while the special circuitry consists of sigma delta, mode matching, temperature/quadrature compensation and novel special technologies. Finally, the characteristics of various typical gyroscopes and their development tendency are discussed and investigated in detail.

  7. The Development of Micromachined Gyroscope Structure and Circuitry Technology

    Directory of Open Access Journals (Sweden)

    Dunzhu Xia

    2014-01-01

    Full Text Available This review surveys micromachined gyroscope structure and circuitry technology. The principle of micromachined gyroscopes is first introduced. Then, different kinds of MEMS gyroscope structures, materials and fabrication technologies are illustrated. Micromachined gyroscopes are mainly categorized into micromachined vibrating gyroscopes (MVGs, piezoelectric vibrating gyroscopes (PVGs, surface acoustic wave (SAW gyroscopes, bulk acoustic wave (BAW gyroscopes, micromachined electrostatically suspended gyroscopes (MESGs, magnetically suspended gyroscopes (MSGs, micro fiber optic gyroscopes (MFOGs, micro fluid gyroscopes (MFGs, micro atom gyroscopes (MAGs, and special micromachined gyroscopes. Next, the control electronics of micromachined gyroscopes are analyzed. The control circuits are categorized into typical circuitry and special circuitry technologies. The typical circuitry technologies include typical analog circuitry and digital circuitry, while the special circuitry consists of sigma delta, mode matching, temperature/quadrature compensation and novel special technologies. Finally, the characteristics of various typical gyroscopes and their development tendency are discussed and investigated in detail.

  8. The integration of surface micromachined devices with optoelectronics: Technology and applications

    Energy Technology Data Exchange (ETDEWEB)

    Warren, M.E.; Blum, O.; Sullivan, C.T.; Shul, R.J.; Rodgers, M.S.; Sniegowski, J.J.

    1998-04-01

    Sandia National Laboratories has a substantial effort in development of microelectromechanical system (MEMS) technologies. This miniaturization capability can lead to low-cost, small, high-performance systems-on-a-chip, and have many applications ranging from advanced military systems to large-volume commercial markets like automobiles, rf or land-based communications networks and equipment, or commercial electronics. One of the key challenges in realization of the microsystem is integration of several technologies including digital electronics; analog and rf electronics, optoelectronics, sensors and actuators, and advanced packaging technologies. In this work they describe efforts in integrating MEMS and optoelectronic or photonic functions and the fabrication constraints on both system components. the MEMS technology used in this work are silicon surface-machined systems fabricated using the SUMMiT (Sandia Ultraplanar Multilevel MEMS Technology) process developed at Sandia. This process includes chemical-mechanical polishing as an intermediate planarization step to allow the use of 4 or 5 levels of polysilicon.

  9. 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.

  10. Effect of glutamic acid on copper sorption onto kaolinite. Batch experiments and surface complexation modeling

    International Nuclear Information System (INIS)

    Karimzadeh, Lotfallah; Barthen, Robert; Gruendig, Marion; Franke, Karsten; Lippmann-Pipke, Johanna; Stockmann, Madlen

    2017-01-01

    In this work, we study the mobility behavior of Cu(II) under conditions related to an alternative, neutrophile biohydrometallurgical Cu(II) leaching approach. Sorption of copper onto kaolinite influenced by glutamic acid (Glu) was investigated in the presence of 0.01 M NaClO 4 by means of binary and ternary batch adsorption measurements over a pH range of 4 to 9 and surface complexation modeling.

  11. Effect of glutamic acid on copper sorption onto kaolinite. Batch experiments and surface complexation modeling

    Energy Technology Data Exchange (ETDEWEB)

    Karimzadeh, Lotfallah; Barthen, Robert; Gruendig, Marion; Franke, Karsten; Lippmann-Pipke, Johanna [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Reactive Transport; Stockmann, Madlen [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Surface Processes

    2017-06-01

    In this work, we study the mobility behavior of Cu(II) under conditions related to an alternative, neutrophile biohydrometallurgical Cu(II) leaching approach. Sorption of copper onto kaolinite influenced by glutamic acid (Glu) was investigated in the presence of 0.01 M NaClO{sub 4} by means of binary and ternary batch adsorption measurements over a pH range of 4 to 9 and surface complexation modeling.

  12. Acceleration of dormant storage effects to address the reliability of silicon surface micromachined Micro-Electro-Mechanical Systems (MEMS).

    Energy Technology Data Exchange (ETDEWEB)

    Cox, James V.; Candelaria, Sam A.; Dugger, Michael Thomas; Duesterhaus, Michelle Ann; Tanner, Danelle Mary; Timpe, Shannon J.; Ohlhausen, James Anthony; Skousen, Troy J.; Jenkins, Mark W.; Jokiel, Bernhard, Jr.; Walraven, Jeremy Allen; Parson, Ted Blair

    2006-06-01

    Qualification of microsystems for weapon applications is critically dependent on our ability to build confidence in their performance, by predicting the evolution of their behavior over time in the stockpile. The objective of this work was to accelerate aging mechanisms operative in surface micromachined silicon microelectromechanical systems (MEMS) with contacting surfaces that are stored for many years prior to use, to determine the effects of aging on reliability, and relate those effects to changes in the behavior of interfaces. Hence the main focus was on 'dormant' storage effects on the reliability of devices having mechanical contacts, the first time they must move. A large number ({approx}1000) of modules containing prototype devices and diagnostic structures were packaged using the best available processes for simple electromechanical devices. The packaging processes evolved during the project to better protect surfaces from exposure to contaminants and water vapor. Packages were subjected to accelerated aging and stress tests to explore dormancy and operational environment effects on reliability and performance. Functional tests and quantitative measurements of adhesion and friction demonstrated that the main failure mechanism during dormant storage is change in adhesion and friction, precipitated by loss of the fluorinated monolayer applied after fabrication. The data indicate that damage to the monolayer can occur at water vapor concentrations as low as 500 ppm inside the package. The most common type of failure was attributed to surfaces that were in direct contact during aging. The application of quantitative methods for monolayer lubricant analysis showed that even though the coverage of vapor-deposited monolayers is generally very uniform, even on hidden surfaces, locations of intimate contact can be significantly depleted in initial concentration of lubricating molecules. These areas represent defects in the film prone to adsorption of

  13. Extracting surface diffusion coefficients from batch adsorption measurement data: application of the classic Langmuir kinetics model.

    Science.gov (United States)

    Chu, Khim Hoong

    2017-11-09

    Surface diffusion coefficients may be estimated by fitting solutions of a diffusion model to batch kinetic data. For non-linear systems, a numerical solution of the diffusion model's governing equations is generally required. We report here the application of the classic Langmuir kinetics model to extract surface diffusion coefficients from batch kinetic data. The use of the Langmuir kinetics model in lieu of the conventional surface diffusion model allows derivation of an analytical expression. The parameter estimation procedure requires determining the Langmuir rate coefficient from which the pertinent surface diffusion coefficient is calculated. Surface diffusion coefficients within the 10 -9 to 10 -6  cm 2 /s range obtained by fitting the Langmuir kinetics model to experimental kinetic data taken from the literature are found to be consistent with the corresponding values obtained from the traditional surface diffusion model. The virtue of this simplified parameter estimation method is that it reduces the computational complexity as the analytical expression involves only an algebraic equation in closed form which is easily evaluated by spreadsheet computation.

  14. Surface micromachined scanning mirrors

    DEFF Research Database (Denmark)

    Mattsson, Kent Erik

    1992-01-01

    Both aluminum cantilever and torsional scanning mirrors have been fabricated and their static and dynamic properties are studied experimentally and theoretically. The experiments showed resonance frequencies in the range of 163 k-Hz - 632 kHz for cantilever beams with Q values between 5 and 11....... Torsional mirrors showed resonance frequencies in the range of 410 kHz - 667 kHz with Q values of 10 - 17. All measurements performed at atmospheric pressure. Both types of mechanical structures were deflected electrostatically at large angles (± 5°) more than 1011 times without breaking and without any...

  15. Micromachined Precision Inertial Instruments

    National Research Council Canada - National Science Library

    Najafi, Khalil

    2003-01-01

    This program focuses on developing inertial-grade micromachined accelerometers and gyroscopes and their associated electronics and packaging for use in a variety of military and commercial applications...

  16. Micromachined electrode array

    Science.gov (United States)

    Okandan, Murat; Wessendorf, Kurt O.

    2007-12-11

    An electrode array is disclosed which has applications for neural stimulation and sensing. The electrode array, in certain embodiments, can include a plurality of electrodes each of which is flexibly attached to a common substrate using a plurality of springs to allow the electrodes to move independently. In other embodiments of the electrode array, the electrodes can be fixed to the substrate. The electrode array can be formed from a combination of bulk and surface micromachining, and can include electrode tips having an electroplated metal (e.g. platinum, iridium, gold or titanium) or a metal oxide (e.g. iridium oxide) for biocompatibility. The electrode array can be used to form a part of a neural prosthesis, and is particularly well adapted for use in an implantable retinal prosthesis.

  17. Micromachined droplet ejector arrays

    Science.gov (United States)

    Perçin, Gökhan; Yaralioglu, Göksenin G.; Khuri-Yakub, Butrus T.

    2002-12-01

    In this article we present a micromachined flextensional droplet ejector array used to eject liquids. By placing a fluid behind one face of a vibrating circular plate that has an orifice at its center, we achieve continuous ejection of the fluid. We present results of ejection of water and isopropanol. The ejector is harmless to sensitive fluids and can be used to eject fuels, organic polymers, photoresists, low-k dielectrics, adhesives, and chemical and biological samples. Micromachined two-dimensional array flextensional droplet ejectors were realized using planar silicon micromachining techniques. Typical resonant frequency of the micromachined device ranges from 400 kHz to 4.5 MHz. The ejections of water through a 4 μm diameter orifice at 3.45 MHz and a 10 μm diameter orifice at 2.15 MHz were demonstrated by using the developed micromachined two-dimensional array ejectors.

  18. Micromachined patch-clamp apparatus

    Science.gov (United States)

    Okandan, Murat

    2012-12-04

    A micromachined patch-clamp apparatus is disclosed for holding one or more cells and providing electrical, chemical, or mechanical stimulation to the cells during analysis with the patch-clamp technique for studying ion channels in cell membranes. The apparatus formed on a silicon substrate utilizes a lower chamber formed from silicon nitride using surface micromachining and an upper chamber formed from a molded polymer material. An opening in a common wall between the chambers is used to trap and hold a cell for analysis using the patch-clamp technique with sensing electrodes on each side of the cell. Some embodiments of the present invention utilize one or more electrostatic actuators formed on the substrate to provide mechanical stimulation to the cell being analyzed, or to provide information about mechanical movement of the cell in response to electrical or chemical stimulation.

  19. Omega-X micromachining system

    International Nuclear Information System (INIS)

    Miller, D.M.

    1978-01-01

    A micromachining tool system with X- and omega-axes is used to machine spherical, aspherical, and irregular surfaces with a maximum contour error of 100 nonometers (nm) and surface waviness of no more than 0.8 nm RMS. The omega axis, named for the angular measurement of the rotation of an eccentric mechanism supporting one end of a tool bar, enables the pulse increments of the tool toward the workpiece to be as little as 0 to 4.4 nm. A dedicated computer coordinates motion in the two axes to produce the workpiece contour. Inertia is reduced by reducing the mass pulsed toward the workpiece to about one-fifth of its former value. The tool system includes calibration instruments to calibrate the micromachining tool system. Backlash is reduced and flexing decreased by using a rotary table and servomotor to pulse the tool in the omega-axis instead of a ball screw mechanism. A thermally-stabilized spindle roates the workpiece and is driven by a motor not mounted on the micromachining tool base through a torque-smoothing pulley and vibrationless rotary coupling. Abbe offset errors are almost eliminated by tool setting and calibration at spindle center height. Tool contour and workpiece contour are gaged on the machine; this enables the source of machining errors to be determined more readily, because the workpiece is gaged before its shape can be changed by removal from the machine

  20. Micro-machined resonator oscillator

    Science.gov (United States)

    Koehler, Dale R.; Sniegowski, Jeffry J.; Bivens, Hugh M.; Wessendorf, Kurt O.

    1994-01-01

    A micro-miniature resonator-oscillator is disclosed. Due to the miniaturization of the resonator-oscillator, oscillation frequencies of one MHz and higher are utilized. A thickness-mode quartz resonator housed in a micro-machined silicon package and operated as a "telemetered sensor beacon" that is, a digital, self-powered, remote, parameter measuring-transmitter in the FM-band. The resonator design uses trapped energy principles and temperature dependence methodology through crystal orientation control, with operation in the 20-100 MHz range. High volume batch-processing manufacturing is utilized, with package and resonator assembly at the wafer level. Unique design features include squeeze-film damping for robust vibration and shock performance, capacitive coupling through micro-machined diaphragms allowing resonator excitation at the package exterior, circuit integration and extremely small (0.1 in. square) dimensioning. A family of micro-miniature sensor beacons is also disclosed with widespread applications as bio-medical sensors, vehicle status monitors and high-volume animal identification and health sensors. The sensor family allows measurement of temperatures, chemicals, acceleration and pressure. A microphone and clock realization is also available.

  1. A level set methodology for predicting the effect of mask wear on surface evolution of features in abrasive jet micro-machining

    International Nuclear Information System (INIS)

    Burzynski, T; Papini, M

    2012-01-01

    A previous implementation of narrow-band level set methodology developed by the authors was extended to allow for the modelling of mask erosive wear in abrasive jet micro-machining (AJM). The model permits the prediction of the surface evolution of both the mask and the target simultaneously, by representing them as a hybrid and continuous mask–target surface. The model also accounts for the change in abrasive mass flux incident to both the target surface and, for the first time, the eroding mask edge, that is brought about by the presence of the mask edge itself. The predictions of the channel surface and eroded mask profiles were compared with measurements on channels machined in both glass and poly-methyl-methacrylate (PMMA) targets at both normal and oblique incidence, using tempered steel and elastomeric masks. A much better agreement between the predicted and measured profiles was found when mask wear was taken into account. Mask wear generally resulted in wider and deeper glass target profiles and wider PMMA target profiles, respectively, when compared to cases where no mask wear was present. This work has important implications for the AJM of complex MEMS and microfluidic devices that require longer machining times. (paper)

  2. Micromachined sensor and actuator research at Sandia`s Microelectronics Development Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Smith, J.H.

    1996-11-01

    An overview of the surface micromachining program at the Microelectronics Development Laboratory of Sandia National Laboratories is presented. Development efforts are underway for a variety of surface micromachined sensors and actuators for both defense and commercial applications. A technology that embeds micromechanical devices below the surface of the wafer prior to microelectronics fabrication has been developed for integrating microelectronics with surface-micromachined micromechanical devices. The application of chemical-mechanical polishing to increase the manufacturability of micromechanical devices is also presented.

  3. Estimating surface turbulent heat fluxes from land surface temperature and soil moisture using the particle batch smoother

    Science.gov (United States)

    Lu, Yang; Dong, Jianzhi; Steele-Dunne, Susan; van de Giesen, Nick

    2016-04-01

    This study is focused on estimating surface sensible and latent heat fluxes from land surface temperature (LST) time series and soil moisture observations. Surface turbulent heat fluxes interact with the overlying atmosphere and play a crucial role in meteorology, hydrology and other climate-related fields, but in-situ measurements are costly and difficult. It has been demonstrated that the time series of LST contains information of energy partitioning and that surface turbulent heat fluxes can be determined from assimilation of LST. These studies are mainly based on two assumptions: (1) a monthly value of bulk heat transfer coefficient under neutral conditions (CHN) which scales the sum of the fluxes, and (2) an evaporation fraction (EF) which stays constant during the near-peak hours of the day. Previous studies have applied variational and ensemble approaches to this problem. Here the newly developed particle batch smoother (PBS) algorithm is adopted to test its capability in this application. The PBS can be seen as an extension of the standard particle filter (PF) in which the states and parameters within a fix window are updated in a batch using all observations in the window. The aim of this study is two-fold. First, the PBS is used to assimilate only LST time series into the force-restore model to estimate fluxes. Second, a simple soil water transfer scheme is introduced to evaluate the benefit of assimilating soil moisture observations simultaneously. The experiments are implemented using the First ISLSCP (International Satellite Land Surface Climatology Project) (FIFE) data. It is shown that the restored LST time series using PBS agrees very well with observations, and that assimilating LST significantly improved the flux estimation at both daily and half-hourly time scales. When soil moisture is introduced to further constrain EF, the accuracy of estimated EF is greatly improved. Furthermore, the RMSEs of retrieved fluxes are effectively reduced at both

  4. Surface-micromachined magnetic undulator with period length between 10  μm and 1 mm for advanced light sources

    Directory of Open Access Journals (Sweden)

    Jere Harrison

    2012-07-01

    Full Text Available A technological gap exists between the μm-scale wiggling periods achieved using electromagnetic waves of high intensity laser pulses and the mm scale of permanent-magnet and superconducting undulators. In the sub-mm range, surface-micromachined soft-magnetic micro-electro-mechanical system inductors with integrated solenoidal coils have already experimentally demonstrated 100 to 500 mT field amplitude across air gaps as large as 15  μm. Simulations indicate that magnetic fields as large as 1.5 T across 50  μm inductor gaps are feasible. A simple rearranging of the yoke and pole geometry allows for fabrication of 10+ cm long undulator structures with period lengths between 12.5  μm and 1 mm. Such undulators find application both in high average power spontaneous emission sources and, if used in combination with ultrahigh-brightness electron beams, could lead to the realization of low energy compact free-electron lasers. Challenges include electron energy broadening due to wakefields and Joule heating in the electromagnet.

  5. Effect of glutamic acid on copper sorption onto kaolinite - Batch experiments and surface complexation modeling.

    Science.gov (United States)

    Karimzadeh, Lotfollah; Barthen, Robert; Stockmann, Madlen; Gruendig, Marion; Franke, Karsten; Lippmann-Pipke, Johanna

    2017-07-01

    High carbonate content of the European Kupferschiefer ore deposits is a challenge for acid copper leaching (pH ≤ 2). Therefore investigating the mobility behavior of Cu(II) under conditions related to an alternative, neutrophil biohydrometallurgical Cu(II) leaching approach is of interest. As glutamic acid (Glu) might be present as a component in the growth media, we studied its effects on the adsorption of Cu(II) onto kaolinite. The binary and ternary batch sorption measurements of Cu(II) and Glu onto kaolinite were performed in the presence of 10 mM NaClO 4 as background electrolyte and at a pH range from 4 to 9. Sorption experiments were modeled by the charge-distribution multi-site ion complexation (CD-MUSIC) model by using single sorption site (≡SOH) and monodentate surface complexation reactions. Glu sorption on kaolinite is weak (kaolinite mimics the Freundlich model. The proposed CD-MUSIC model provides a close fit to the experimental data and predicts the sorption of Cu(II), Cu(II)-Glu and Glu onto kaolinite as well as the effect of Glu on Cu(II) mobility. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Micromachining with copper lasers

    Science.gov (United States)

    Knowles, Martyn R. H.; Bell, Andy; Foster-Turner, Gideon; Rutterford, Graham; Chudzicki, J.; Kearsley, Andrew J.

    1997-04-01

    In recent years the copper laser has undergone extensive development and has emerged as a leading and unique laser for micromachining. The copper laser is a high average power (10 - 250 W), high pulse repetition rate (2 - 32 kHz), visible laser (511 nm and 578 nm) that produces high peak power (typically 200 kW), short pulses (30 ns) and very good beam quality (diffraction limited). This unique set of laser parameters results in exceptional micro-machining in a wide variety of materials. Typical examples of the capabilities of the copper laser include the drilling of small holes (10 - 200 micrometer diameter) in materials as diverse as steel, ceramic, diamond and polyimide with micron precision and low taper (less than 1 degree) cutting and profiling of diamond. Application of the copper laser covers the electronic, aerospace, automotive, nuclear, medical and precision engineering industries.

  7. The micromachined logo of Atomki

    International Nuclear Information System (INIS)

    Rajta, I.; Szilasi, S.Z.

    2006-01-01

    Complete text of publication follows. Proton Beam Micromachining, also known as P-beam Writing, is a direct write 3- dimensional lithographic technique. Conventional resist types are PMMA (polymethylmethacrylate), and SU-8 (of MicroChem Corp.); they are positive and negative resists, respectively. In this work we used SU-8, the most common negative resist material. SU-8 was spun on a flat surface, typically Silicon or glass. A direct write proton beam was scanned over an arbitary structure (the Atomki logo can be replaced by any other structure), which produces chain scissioning in the polymer. Post exposure bake (PEB) is usually needed in case of conventional optical lithography, but using protons this bake is done in situ as the ions heat up the sample in vacuum. Subsequently chemical etching takes place, the solvent is available at MicroChem Corp. The schematic diagram of the above described micromachining process is shown on Fig. 1. The irradiation requires a scanning proton microbeam system equipped with suitable beam scanning and blanking facilities. This is available in the Institute, our setup has been upgraded from doublet to triplet focusing system (Oxford Microbeams Ltd.). For scanning we use a DIO card (PCI-6731 of National Instruments), and the IonScan software [1]. Sample preparation was carried out at our 'semi clean' room. This is also where chemical development of the samples and the optical microscopy have been done too. A Zeiss Axio Imager microscope is available (equipped with 5 objective lenses, 4 different contrast methods, transmitted or reflected light illumination). Fig. 2. shows a typical example of the Atomki logo. This is a bright field image, a number of different nice and colourful images can be produced with the other contrast techniques (for more images see the Institute website: http://www.atomki.hu/ ). (author)

  8. Multi-Level Micromachined Systems-on-a-Chip: Technology and Applications

    Energy Technology Data Exchange (ETDEWEB)

    Allen, J.J.; Krygowski, T.W.; Miller, S.L.; Montague, S.; Rodgers, M.S.; Smith, J.H.; Sniegowski, J.J.

    1998-10-27

    Researchers at Sandia have recently designed and built several research prototypes, which demonstrate that truly complex mechanical systems can now be realized in a surface micromachined technology. These MicroElectro- Mechanical Systems (MEMS) include advanced actuators, torque multiplying gear tmins, rack and pinion assemblies, positionable mirrors, and mechanical discriminators. All of tile mechanical components are batch fabricated on a single chip of silicon using the infrastructure origimdly developed to support today's highly reliabk; and robust microelectronics industry. Sand ia is also developing the technology 10 integrate microelectronic circuits onto the s,ime piece of silicon that is used to fabricate the MEMS devices. This significantly increases sensitivity and reliability, while fhrther reducing package size and fabrication costs. A review of the MEMS technology and capabilities available at Sandia National Laboratories is presented.

  9. Trends in laser micromachining

    Science.gov (United States)

    Gaebler, Frank; van Nunen, Joris; Held, Andrew

    2016-03-01

    Laser Micromachining is well established in industry. Depending on the application lasers with pulse length from μseconds to femtoseconds and wavelengths from 1064nm and its harmonics up to 5μm or 10.6μm are used. Ultrafast laser machining using pulses with pico or femtosecond duration pulses is gaining traction, as it offers very precise processing of materials with low thermal impact. Large-scale industrial ultrafast laser applications show that the market can be divided into various sub segments. One set of applications demand low power around 10W, compact footprint and are extremely sensitive to the laser price whilst still demanding 10ps or shorter laser pulses. A second set of applications are very power hungry and only become economically feasible for large scale deployments at power levels in the 100+W class. There is also a growing demand for applications requiring fs-laser pulses. In our presentation we would like to describe these sub segments by using selected applications from the automotive and electronics industry e.g. drilling of gas/diesel injection nozzles, dicing of LED substrates. We close the presentation with an outlook to micromachining applications e.g. glass cutting and foil processing with unique new CO lasers emitting 5μm laser wavelength.

  10. Micromachining with Nanostructured Cutting Tools

    CERN Document Server

    Jackson, Mark J

    2013-01-01

    The purpose of the brief is to explain how nanostructured tools can be used to machine materials at the microscale.  The aims of the brief are to explain to readers how to apply nanostructured tools to micromachining applications. This book describes the application of nanostructured tools to machining engineering materials and includes methods for calculating basic features of micromachining. It explains the nature of contact between tools and work pieces to build a solid understanding of how nanostructured tools are made.

  11. Silicon-micromachined microchannel plates

    Energy Technology Data Exchange (ETDEWEB)

    Beetz, Charles P. E-mail: NanoSystem@aol.com; Boerstler, Robert; Steinbeck, John; Lemieux, Bryan; Winn, David R. E-mail: winn@fair1.fairfield.edu

    2000-03-11

    Microchannel plates (MCP) fabricated from standard silicon wafer substrates using a novel silicon micromachining process, together with standard silicon photolithographic process steps, are described. The resulting SiMCP microchannels have dimensions of {approx}0.5 to {approx}25 {mu}m, with aspect ratios up to 300, and have the dimensional precision and absence of interstitial defects characteristic of photolithographic processing, compatible with positional matching to silicon electronics readouts. The open channel areal fraction and detection efficiency may exceed 90% on plates up to 300 mm in diameter. The resulting silicon substrates can be converted entirely to amorphous quartz (qMCP). The strip resistance and secondary emission are developed by controlled depositions of thin films, at temperatures up to 1200 deg. C, also compatible with high-temperature brazing, and can be essentially hydrogen, water and radionuclide-free. Novel secondary emitters and cesiated photocathodes can be high-temperature deposited or nucleated in the channels or the first strike surface. Results on resistivity, secondary emission and gain are presented.

  12. Silicon-micromachined microchannel plates

    Science.gov (United States)

    Beetz, Charles P.; Boerstler, Robert; Steinbeck, John; Lemieux, Bryan; Winn, David R.

    2000-03-01

    Microchannel plates (MCP) fabricated from standard silicon wafer substrates using a novel silicon micromachining process, together with standard silicon photolithographic process steps, are described. The resulting SiMCP microchannels have dimensions of ˜0.5 to ˜25 μm, with aspect ratios up to 300, and have the dimensional precision and absence of interstitial defects characteristic of photolithographic processing, compatible with positional matching to silicon electronics readouts. The open channel areal fraction and detection efficiency may exceed 90% on plates up to 300 mm in diameter. The resulting silicon substrates can be converted entirely to amorphous quartz (qMCP). The strip resistance and secondary emission are developed by controlled depositions of thin films, at temperatures up to 1200°C, also compatible with high-temperture brazing, and can be essentially hydrogen, water and radionuclide-free. Novel secondary emitters and cesiated photocathodes can be high-temperature deposited or nucleated in the channels or the first strike surface. Results on resistivity, secondary emission and gain are presented.

  13. Silicon-micromachined microchannel plates

    International Nuclear Information System (INIS)

    Beetz, Charles P.; Boerstler, Robert; Steinbeck, John; Lemieux, Bryan; Winn, David R.

    2000-01-01

    Microchannel plates (MCP) fabricated from standard silicon wafer substrates using a novel silicon micromachining process, together with standard silicon photolithographic process steps, are described. The resulting SiMCP microchannels have dimensions of ∼0.5 to ∼25 μm, with aspect ratios up to 300, and have the dimensional precision and absence of interstitial defects characteristic of photolithographic processing, compatible with positional matching to silicon electronics readouts. The open channel areal fraction and detection efficiency may exceed 90% on plates up to 300 mm in diameter. The resulting silicon substrates can be converted entirely to amorphous quartz (qMCP). The strip resistance and secondary emission are developed by controlled depositions of thin films, at temperatures up to 1200 deg. C, also compatible with high-temperature brazing, and can be essentially hydrogen, water and radionuclide-free. Novel secondary emitters and cesiated photocathodes can be high-temperature deposited or nucleated in the channels or the first strike surface. Results on resistivity, secondary emission and gain are presented

  14. Capacitive micromachined ultrasonic transducer based tilt sensing

    Science.gov (United States)

    Yu, Hongbin; Guo, Bin; Haridas, Kuruveettil; Lin, Tsu-Hui; Hao Cheong, Jia; Lin Tsai, Ming; Boon Yee, Tack

    2012-10-01

    In this paper, a tilt sensing mechanism based on the capacitive micromachined ultrasound transducers (CMUTs) is presented. By measuring the difference in the time of flight of various pulse-echo signals from different CMUT transmitting elements to one common receiving element in the oil bath, the tilt angle of the oil surface can be determined. With the proposed device, the maximum tilt angles of 20° and 28° have been measured in the clockwise and counterclockwise directions, respectively, and the difference between the measured and the theoretical values of the tilt angle was found to be within 0.05° during the whole test.

  15. Modeling Grinding Processes as Micro-Machining Operation ...

    African Journals Online (AJOL)

    A computational based model for surface grinding process as a micro-machined operation has been developed. In this model, grinding forces are made up of chip formation force and sliding force. Mathematical expressions for Modeling tangential grinding force and normal grinding force were obtained. The model was ...

  16. Electron beam micromachining of plastics

    Czech Academy of Sciences Publication Activity Database

    Dupák, Libor

    2014-01-01

    Roč. 49, 5-6 (2014), s. 310-314 ISSN 0861-4717 R&D Projects: GA MŠk(CZ) LO1212; GA MŠk ED0017/01/01; GA MŠk EE.2.3.20.0103 Institutional support: RVO:68081731 Keywords : micromachining of plastics * Electron beam Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering

  17. Landfill leachate treatment using powdered activated carbon augmented sequencing batch reactor (SBR) process: Optimization by response surface methodology

    International Nuclear Information System (INIS)

    Aziz, Shuokr Qarani; Aziz, Hamidi Abdul; Yusoff, Mohd Suffian; Bashir, Mohammed J.K.

    2011-01-01

    In this study, landfill leachate was treated by using the sequencing batch reactor (SBR) process. Two types of the SBR, namely non-powdered activated carbon and powdered activated carbon (PAC-SBR) were used. The influence of aeration rate and contact time on SBR and PAC-SBR performances was investigated. Removal efficiencies of chemical oxygen demand (COD), colour, ammoniacal nitrogen (NH 3 -N), total dissolved salts (TDS), and sludge volume index (SVI) were monitored throughout the experiments. Response surface methodology (RSM) was applied for experimental design, analysis and optimization. Based on the results, the PAC-SBR displayed superior performance in term of removal efficiencies when compared to SBR. At the optimum conditions of aeration rate of 1 L/min and contact time of 5.5 h the PAC-SBR achieved 64.1%, 71.2%, 81.4%, and 1.33% removal of COD, colour, NH 3 -N, and TDS, respectively. The SVI value of PAC-SBR was 122.2 mL/g at optimum conditions.

  18. Landfill leachate treatment using powdered activated carbon augmented sequencing batch reactor (SBR) process: Optimization by response surface methodology

    Energy Technology Data Exchange (ETDEWEB)

    Aziz, Shuokr Qarani [School of Civil Engineering, Universiti Sains Malaysia (USM), 14300 Nibong Tebal, Penang (Malaysia); Aziz, Hamidi Abdul, E-mail: cehamidi@eng.usm.my [School of Civil Engineering, Universiti Sains Malaysia (USM), 14300 Nibong Tebal, Penang (Malaysia); Yusoff, Mohd Suffian; Bashir, Mohammed J.K. [School of Civil Engineering, Universiti Sains Malaysia (USM), 14300 Nibong Tebal, Penang (Malaysia)

    2011-05-15

    In this study, landfill leachate was treated by using the sequencing batch reactor (SBR) process. Two types of the SBR, namely non-powdered activated carbon and powdered activated carbon (PAC-SBR) were used. The influence of aeration rate and contact time on SBR and PAC-SBR performances was investigated. Removal efficiencies of chemical oxygen demand (COD), colour, ammoniacal nitrogen (NH{sub 3}-N), total dissolved salts (TDS), and sludge volume index (SVI) were monitored throughout the experiments. Response surface methodology (RSM) was applied for experimental design, analysis and optimization. Based on the results, the PAC-SBR displayed superior performance in term of removal efficiencies when compared to SBR. At the optimum conditions of aeration rate of 1 L/min and contact time of 5.5 h the PAC-SBR achieved 64.1%, 71.2%, 81.4%, and 1.33% removal of COD, colour, NH{sub 3}-N, and TDS, respectively. The SVI value of PAC-SBR was 122.2 mL/g at optimum conditions.

  19. Bionics: prcise color tuning by interference in nature and technology-applications in surface-micromachined 1.55μm vertical air-cavity filters

    Science.gov (United States)

    Hillmer, Hartmut; Daleiden, Juergen; Prott, Cornelia; Irmer, Soeren; Roemer, Friedhard; Ataro, Edwin; Tarraf, Amer; Ruehling, H.; Maniak, Markus; Strassner, Martin

    2003-01-01

    Bionics transfers the principles of success of nature into natural science, engineering disciplines and applications. Often generation and detection of different spectral colors play key roles in communication in both, nature and technology. The latter one refers e.g. to dense wavelength division multiplex optical communication systems. This paper shows interesting parallels in tunable spectral light filtering by butterfly wings and by tunable optical filters used in optical communication systems. In both cases light interferes constructively and destructively with nano- and microstructures of appropriate shape, dimensions and materials. In this paper methodology is strongly emphasized. We demonstrate that tailored scaling allows the effectiveness of physical effects to be enhanced in nature and technology. These principles are rigorously applied in micromachined 1.55μm vertical-resonator-based filters, capable of wide, continuous, monotonic and kink-free tuning by a single control parameter. Tuning is achieved by mechanically actuating one or several membranes embedded by air-gaps in a vertical resonator including two ultra-highly reflective DBR mirrors. The layers of mirrors reveal a very strong refractive index contrast. Filters including InP/air-gap DBR's (3.5 periods) using GaInAs sacrificial layers reveal a continuous tuning of >9% of the absolute wavelength. Varying a reverse voltage (U=0 .. -3.2V) between the membranes, a tuning range up to 142nm was obtained due to electrostatic actuation. Appropriate miniaturization is shown to increase the mechanical stability and the effectiveness of spectral tuning by electrostatic actuation since the relative significance of the fundamental physical forces can be shifted considerably by appropriate scaling.

  20. Laser Micromachining of Glass, Silicon, and Ceramics

    Directory of Open Access Journals (Sweden)

    L. Rihakova

    2015-01-01

    Full Text Available A brief review is focused on laser micromachining of materials. Micromachining of materials is highly widespread method used in many industries, including semiconductors, electronic, medical, and automotive industries, communication, and aerospace. This method is a promising tool for material processing with micron and submicron resolution. In this paper micromachining of glass, silicon, and ceramics is considered. Interaction of these materials with laser radiation and recent research held on laser material treatment is provided.

  1. Fabrication of a novel quartz micromachined gyroscope

    Directory of Open Access Journals (Sweden)

    Liqiang Xie

    2015-04-01

    Full Text Available A novel quartz micromachined gyroscope is proposed in this paper. The novel gyroscope is realized by quartz anisotropic wet etching and 3-dimensional electrodes deposition. In the quartz wet etching process, the quality of Cr/Au mask films affecting the process are studied by experiment. An excellent mask film with 100 Å Cr and 2000 Å Au is achieved by optimization of experimental parameters. Crystal facets after etching seriously affect the following sidewall electrodes deposition process and the structure’s mechanical behaviours. Removal of crystal facets is successfully implemented by increasing etching time based on etching rate ratios between facets and crystal planes. In the electrodes deposition process, an aperture mask evaporation method is employed to prepare electrodes on 3-dimensional surfaces of the gyroscope structure. The alignments among the aperture masks are realized by the ABM™ Mask Aligner System. Based on the processes described above, a z–axis quartz gyroscope is fabricated successfully.

  2. 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.

  3. Capacitive micromachined ultrasonic transducers with through-wafer interconnects

    Science.gov (United States)

    Zhuang, Xuefeng

    Capacitive micromachined ultrasonic transducer (CMUT) is a promising candidate for making ultrasound transducer arrays for applications such as 3D medical ultrasound, non-destructive evaluation and chemical sensing. Advantages of CMUTs over traditional piezoelectric transducers include low-cost batch fabrication, wide bandwidth, and ability to fabricate arrays with broad operation frequency range and different geometric configurations on a single wafer. When incorporated with through-wafer interconnects, a CMUT array can be directly integrated with a front-end integrated circuit (IC) to achieve compact packaging and to mitigate the effects of the parasitic capacitance from the connection cables. Through-wafer via is the existing interconnect scheme for CMUT arrays, and many other types of micro-electro-mechanical system (MEMS) devices. However, to date, no successful through-wafer via fabrication technique compatible with the wafer-bonding method of making CMUT arrays has been demonstrated. The through-wafer via fabrication steps degrade the surface conditions of the wafer, reduce the radius of curvature, thus making it difficult to bond. This work focuses on new through-wafer interconnect techniques that are compatible with common MEMS fabrication techniques, including both surface-micromachining and direct wafer-to-wafer fusion bonding. In this dissertation, first, a through-wafer via interconnect technique with improved characteristics is presented. Then, two implementations of through-wafer trench isolation are demonstrated. The through-wafer trench methods differ from the through-wafer vias in that the electrical conduction is through the bulk silicon instead of the conductor in the vias. In the first implementation, a carrier wafer is used to provide mechanical support; in the second, mechanical support is provided by a silicon frame structure embedded inside the isolation trenches. Both implementations reduce fabrication complexity compared to the through

  4. Mechanical Micro-Machining and Laser Micro-Machining

    Science.gov (United States)

    Lou, Ning

    Ever since the 2000s, the manufacturing industry has gained tremendous development in terms of precision. Therefore, micro-machining as a cutting-edge technique has drawn more and more attention in precision-machining realm and been able to take on challenges brought by this. This doctoral program explores the micro-machining realm and results are consisted of two major parts. First, the machinability of "difficult-to-cut" materials is of interest where Inconel 718 is selected as its characteristics include outstanding strength and lackluster thermal conductivity. For its extraordinary hardness and sustainability, coated cemented carbide tools are selected for micro-endmilling processes on Inconel. The cutting forces along x and y axis, respectively, are analyzed to reveal any impact from the inputs. Moreover, the chip morphology is examined. Suggestions are made for future research guidance. As first part serves as preliminary work of the program, the research carries onto the second part - laser micro-machining which is considerably different from conventional machining. The laser being considered employs pulsewidth in realm of picosecond (10-12 s) and frequency of tens of kilohertz. This results in a very small energy distribution per pulse (microJ) and is called ultrafast or ultrashort laser machining. To study this type of technology, an all-new machining system needs to be built incorporating highly advanced apparatus such as laser head, scan head, attenuator, and beam expander, et al. From exit of laser head to workpiece, laser need to travel through all optical components and any deviation may leads to severe out-of-focus error as the depth of focus is within micron level. Thus, optical alignment along laser travelling route is key to successful machining results. This part of research focuses on the design and assembly of this system as a reliable structure offering both support and alignment to the laser delivery. 3-Dimentional (3D) Computer

  5. Micro-machined calorimetric biosensors

    Science.gov (United States)

    Doktycz, Mitchel J.; Britton, Jr., Charles L.; Smith, Stephen F.; Oden, Patrick I.; Bryan, William L.; Moore, James A.; Thundat, Thomas G.; Warmack, Robert J.

    2002-01-01

    A method and apparatus are provided for detecting and monitoring micro-volumetric enthalpic changes caused by molecular reactions. Micro-machining techniques are used to create very small thermally isolated masses incorporating temperature-sensitive circuitry. The thermally isolated masses are provided with a molecular layer or coating, and the temperature-sensitive circuitry provides an indication when the molecules of the coating are involved in an enthalpic reaction. The thermally isolated masses may be provided singly or in arrays and, in the latter case, the molecular coatings may differ to provide qualitative and/or quantitative assays of a substance.

  6. Short communication.Wood identification based on their common name and their transversal surface anatomy. Application to the batch from the expedition of Ruiz and Pavon

    OpenAIRE

    Villasante Plágaro, Antonio M.

    2011-01-01

    Aim of study: To identify species of wood samples based on common names and anatomical analyses of their transversal surfaces (without microscopic preparations).Area of study: Spain and South America.Material and Methods: The test was carried out on a batch of 15 lumber samples deposited in the Royal Botanical Garden in Madrid, from the expedition by Ruiz and Pavón (1777-1811). The first stage of the methodology is to search and to make a critical analysis of the databases which list common n...

  7. Micromachined Thermal Flow Sensors—A Review

    Directory of Open Access Journals (Sweden)

    Jonathan T. W. Kuo

    2012-07-01

    Full Text Available Microfabrication has greatly matured and proliferated in use amongst many disciplines. There has been great interest in micromachined flow sensors due to the benefits of miniaturization: low cost, small device footprint, low power consumption, greater sensitivity, integration with on-chip circuitry, etc. This paper reviews the theory of thermal flow sensing and the different configurations and operation modes available. Material properties relevant to micromachined thermal flow sensing and selection criteria are also presented. Finally, recent applications of micromachined thermal flow sensors are presented. Detailed tables of the reviewed devices are included.

  8. Vascular tissue engineering by computer-aided laser micromachining.

    Science.gov (United States)

    Doraiswamy, Anand; Narayan, Roger J

    2010-04-28

    Many conventional technologies for fabricating tissue engineering scaffolds are not suitable for fabricating scaffolds with patient-specific attributes. For example, many conventional technologies for fabricating tissue engineering scaffolds do not provide control over overall scaffold geometry or over cell position within the scaffold. In this study, the use of computer-aided laser micromachining to create scaffolds for vascular tissue networks was investigated. Computer-aided laser micromachining was used to construct patterned surfaces in agarose or in silicon, which were used for differential adherence and growth of cells into vascular tissue networks. Concentric three-ring structures were fabricated on agarose hydrogel substrates, in which the inner ring contained human aortic endothelial cells, the middle ring contained HA587 human elastin and the outer ring contained human aortic vascular smooth muscle cells. Basement membrane matrix containing vascular endothelial growth factor and heparin was to promote proliferation of human aortic endothelial cells within the vascular tissue networks. Computer-aided laser micromachining provides a unique approach to fabricate small-diameter blood vessels for bypass surgery as well as other artificial tissues with complex geometries.

  9. Micromachined Integrated Transducers for Ultrasound Imaging

    DEFF Research Database (Denmark)

    la Cour, Mette Funding

    The purpose of this project is to develop capacitive micromachined ultrasonic transducers (CMUTs) for medical imaging. Medical ultrasound transducers used today are fabricated using piezoelectric materials and bulk processing. To fabricate transducers capable of delivering a higher imaging...

  10. Development of a micromachined electrostatically suspended gyroscope

    OpenAIRE

    Damrongsak, Badin

    2009-01-01

    In this thesis, a new approach based on an electrostatically suspended gyroscope (ESG) was explored in order to improve the performance of micromachined gyroscopes. Typically, a conventional micromachined gyroscope consists of a vibrating mass suspended on elastic beams that are anchored to a substrate. It measures the rotation rate of a body of interest by detecting rotation-induced Coriolis acceleration of a vibrating structure. Such a gyro is sensitive to fabrication imperfections an...

  11. Laser Micromachining and Information Discovery Using a Dual Beam Interferometry

    Energy Technology Data Exchange (ETDEWEB)

    Theppakuttaikomaraswamy, Senthil P. [Iowa State Univ., Ames, IA (United States)

    2001-01-01

    Lasers have proven to be among the most promising tools for micromachining because they can process features down to the size of the laser wavelength (smaller than 1 micrometer) and they provide a non-contact technology for machining. The demand for incorporating in-situ diagnostics technology into the micromachining environment is driven by the increasing need for producing micro-parts of high quality and accuracy. Laser interferometry can be used as an on-line monitoring tool and it is the aim of this work to enhance the understanding and application of Michelson interferometry principle for the in-situ diagnostics of the machining depth on the sub-micron and micron scales. micromachining is done on two different materials and a comprehensive investigation is done to control the width and depth of the machined feature. To control the width of the feature, laser micromachining is done on copper and a detailed analysis is performed. The objective of this experiment is to make a precision mask for sputtering with an array of holes on it using an Nd:YAG laser of 532 nm wavelength. The diameter of the hole is 50 μm and the spacing between holes (the distance between the centers) is 100 μm. Michelson interferometer is integrated with a laser machining system to control the depth of machining. An excimer laser of 308 nm wavelength is used for micromachining. A He-Ne laser of 632.8 nm wavelength is used as the light source for the interferometer. Interference patterns are created due to the change in the path length between the two interferometer arms. The machined depth information is obtained from the interference patterns on an oscilloscope detected by a photodiode. To compare the predicted depth by the interferometer with the true machining depth, a surface profilometer is used to measure the actual machining depth on the silicon. It is observed that the depths of machining obtained by the surface profile measurement are in accordance with the interferometer

  12. Short Communication. Wood identification based on their common name and their transversal surface anatomy. Application to the batch from the expedition of Ruiz and Pavon

    Directory of Open Access Journals (Sweden)

    A. Villasante

    2013-03-01

    Full Text Available Aim of study: To identify species of wood samples based on common names and anatomical analyses of their transversal surfaces (without microscopic preparations.Area of study: Spain and South America.Material and Methods: The test was carried out on a batch of 15 lumber samples deposited in the Royal Botanical Garden in Madrid, from the expedition by Ruiz and Pavón (1777-1811. The first stage of the methodology is to search and to make a critical analysis of the databases which list common nomenclature along with scientific nomenclature. A geographic filter was then applied to the information resulting from the samples with a more restricted distribution. Finally an anatomical verification was carried out with a pocket microscope with a magnification of x40, equipped with a 50 micrometers resolution scale.Main results: The identification of the wood based exclusively on the common name is not useful due to the high number of alternative possibilities (14 for “naranjo”, 10 for “ébano”, etc.. The common name of one of the samples (“huachapelí mulato” enabled the geographic origin of the samples to be accurately located to the shipyard area in Guayaquil (Ecuador. Given that Ruiz y Pavón did not travel to Ecuador, the specimens must have been obtained by Tafalla. It was possible to determine correctly 67% of the lumber samples from the batch. In 17% of the cases the methodology did not provide a reliable identification.Research highlights: It was possible to determine correctly 67% of the lumber samples from the batch and their geographic provenance. The identification of the wood based exclusively on the common name is not useful.Key words: historic wood; Ruiz and Pavon’s expedition; wood anatomy; wood identification; wood nomenclature.

  13. Short communication.Wood identification based on their common name and their transversal surface anatomy. Application to the batch from the expedition of Ruiz and Pavon

    Energy Technology Data Exchange (ETDEWEB)

    Villasante, A.

    2013-05-01

    Aim of study: To identify species of wood samples based on common names and anatomical analyses of their transversal surfaces (without microscopic preparations). Area of study: Spain and South America Material and methods: The test was carried out on a batch of 15 lumber samples deposited in the Royal Botanical Garden in Madrid, from the expedition by Ruiz and Pavon (1777-1811). The first stage of the methodology is to search and to make a critical analysis of the databases which list common nomenclature along with scientific nomenclature. A geographic filter was then applied to the information resulting from the samples with a more restricted distribution. Finally an anatomical verification was carried out with a pocket microscope with a magnification of x40, equipped with a 50 micrometers resolution scale. Main results: The identification of the wood based exclusively on the common name is not useful due to the high number of alternative possibilities (14 for naranjo, 10 for ebano, etc.). The common name of one of the samples (huachapeli mulato) enabled the geographic origin of the samples to be accurately located to the shipyard area in Guayaquil (Ecuador). Given that Ruiz y Pavon did not travel to Ecuador, the specimens must have been obtained by Tafalla. It was possible to determine correctly 67% of the lumber samples from the batch. In 17% of the cases the methodology did not provide a reliable identification. Research highlights: It was possible to determine correctly 67% of the lumber samples from the batch and their geographic provenance. (Author) 11 refs.

  14. Acoustic lens for capacitive micromachined ultrasonic transducers

    Science.gov (United States)

    Chang, Chienliu; Firouzi, Kamyar; Park, Kwan Kyu; Sarioglu, Ali Fatih; Nikoozadeh, Amin; Yoon, Hyo-Seon; Vaithilingam, Srikant; Carver, Thomas; Khuri-Yakub, Butrus T.

    2014-08-01

    Capacitive micromachined ultrasonic transducers (CMUTs) have great potential to compete with traditional piezoelectric transducers in therapeutic ultrasound applications. In this paper we have designed, fabricated and developed an acoustic lens formed on the CMUT to mechanically focus ultrasound. The acoustic lens was designed based on the paraxial theory and made of silicone rubber for acoustic impedance matching and encapsulation. The CMUT was fabricated based on the local oxidation of silicon (LOCOS) and fusion-bonding. The fabricated CMUT was verified to behave like an electromechanical resonator in air and exhibited wideband response with a center frequency of 2.2 MHz in immersion. The fabrication for the acoustic lens contained two consecutive mold castings and directly formed on the surface of the CMUT. Applied with ac burst input voltages at the center frequency, the CMUT with the acoustic lens generated an output pressure of 1.89 MPa (peak-to-peak) at the focal point with an effective focal gain of 3.43 in immersion. Compared to the same CMUT without a lens, the CMUT with the acoustic lens demonstrated the ability to successfully focus ultrasound and provided a viable solution to the miniaturization of the multi-modality forward-looking endoscopes without electrical focusing.

  15. Acoustic lens for capacitive micromachined ultrasonic transducers

    International Nuclear Information System (INIS)

    Chang, Chienliu; Firouzi, Kamyar; Sarioglu, Ali Fatih; Nikoozadeh, Amin; Yoon, Hyo-Seon; Vaithilingam, Srikant; Carver, Thomas; Khuri-Yakub, Butrus T; Kyu Park, Kwan

    2014-01-01

    Capacitive micromachined ultrasonic transducers (CMUTs) have great potential to compete with traditional piezoelectric transducers in therapeutic ultrasound applications. In this paper we have designed, fabricated and developed an acoustic lens formed on the CMUT to mechanically focus ultrasound. The acoustic lens was designed based on the paraxial theory and made of silicone rubber for acoustic impedance matching and encapsulation. The CMUT was fabricated based on the local oxidation of silicon (LOCOS) and fusion-bonding. The fabricated CMUT was verified to behave like an electromechanical resonator in air and exhibited wideband response with a center frequency of 2.2 MHz in immersion. The fabrication for the acoustic lens contained two consecutive mold castings and directly formed on the surface of the CMUT. Applied with ac burst input voltages at the center frequency, the CMUT with the acoustic lens generated an output pressure of 1.89 MPa (peak-to-peak) at the focal point with an effective focal gain of 3.43 in immersion. Compared to the same CMUT without a lens, the CMUT with the acoustic lens demonstrated the ability to successfully focus ultrasound and provided a viable solution to the miniaturization of the multi-modality forward-looking endoscopes without electrical focusing. (paper)

  16. Micromachining Lithium Niobate for Rapid Prototyping of Resonant Biosensors

    International Nuclear Information System (INIS)

    Al-Shibaany, Zeyad Yousif Abdoon; Hedley, John; Huo, Dehong; Hu, Zhongxu

    2014-01-01

    Lithium niobate material is widely used in MEMS application due to its piezoelectric properties. This paper presents the micromachining process of lithium niobate to rapid prototype a resonant biosensor design. A high precision CNC machine was used to machine a sample of lithium niobate material at 5 different spindle speeds to find out the best conditions to machine this brittle material. A qualitative visual check of the surface was performed by using scanning electron microscopy, surface roughness was quantitatively investigated using an optical surface profiler and Raman spectroscopy to check the strain of the surface. Results show that the surface quality of the lithium niobate was significantly affected by the spindle speed with optimum conditions at 70k rpm giving a strained surface with 500 nm rms roughness

  17. Acoustic mode converters micromachined in silicon by proton beam writing

    International Nuclear Information System (INIS)

    Scholz, U.; Menzel, F.; Pluta, M.; Grill, W.; Butz, T.

    2011-01-01

    Proton beam writing is a powerful tool for the production of microstructures for acoustic applications because it allows to create structures inclined to the original sample surface which therefore can act as acoustic mode converters. We report on experiments, finding optimal structure sizes in p-type 12 Ω cm silicon for this purpose. For the creation of the structures the proton beam at the LIPSION laboratory was used. Furthermore, by investigating the micromachined silicon with a phase sensitive acoustic microscope we give evidence that inclined structures such as rods and walls can be used to change the mode of acoustic waves in the crystal.

  18. Physics-based signal processing algorithms for micromachined cantilever arrays

    Science.gov (United States)

    Candy, James V; Clague, David S; Lee, Christopher L; Rudd, Robert E; Burnham, Alan K; Tringe, Joseph W

    2013-11-19

    A method of using physics-based signal processing algorithms for micromachined cantilever arrays. The methods utilize deflection of a micromachined cantilever that represents the chemical, biological, or physical element being detected. One embodiment of the method comprises the steps of modeling the deflection of the micromachined cantilever producing a deflection model, sensing the deflection of the micromachined cantilever and producing a signal representing the deflection, and comparing the signal representing the deflection with the deflection model.

  19. New Effective Material Couple--Oxide Ceramic and Carbon Nanotube-- Developed for Aerospace Microsystem and Micromachine Technologies

    Science.gov (United States)

    Miyoshi, Kazuhisa; VanderWal, Randall L.; Tomasek, Aaron J.; Sayir, Ali; Farmer, Serene C.

    2004-01-01

    The prime driving force for using microsystem and micromachine technologies in transport vehicles, such as spacecraft, aircraft, and automobiles, is to reduce the weight, power consumption, and volume of components and systems to lower costs and increase affordability and reliability. However, a number of specific issues need to be addressed with respect to using microsystems and micromachines in aerospace applications--such as the lack of understanding of material characteristics; methods for producing and testing the materials in small batches; the limited proven durability and lifetime of current microcomponents, packaging, and interconnections; a cultural change with respect to system designs; and the use of embedded software, which will require new product assurance guidelines. In regards to material characteristics, there are significant adhesion, friction, and wear issues in using microdevices. Because these issues are directly related to surface phenomena, they cannot be scaled down linearly and they become increasingly important as the devices become smaller. When microsystems have contacting surfaces in relative motion, the adhesion and friction affect performance, energy consumption, wear damage, maintenance, lifetime and catastrophic failure, and reliability. Ceramics, for the most part, do not have inherently good friction and wear properties. For example, coefficients of friction in excess of 0.7 have been reported for ceramics and ceramic composite materials. Under Alternate Fuels Foundation Technologies funding, two-phase oxide ceramics developed for superior high-temperature wear resistance in NASA's High Operating Temperature Propulsion Components (HOTPC) project and new two-layered carbon nanotube (CNT) coatings (CNT topcoat/iron bondcoat/quartz substrate) developed in NASA's Revolutionary Aeropropulsion Concepts (RAC) project have been chosen as a materials couple for aerospace applications, including micromachines, in the nanotechnology

  20. Micromachined gyroscopes: challenges, design solutions, and opportunities

    Science.gov (United States)

    Shkel, Andrei M.

    2001-08-01

    Micromachined gyroscopes are probably the most challenging type of transducers ever attempted to be designed in micro-world. A nail-size dynamic system integrated with control electronics on the same silicon chip is designed to be a very sensitive sensor which is potentially able to detect maneuvers and motions beyond human perception. Along with exciting opportunities which MEMS gyroscopes could bring to everyday life, the miniaturization introduces many new technical challenges. Multi-degree of freedom dynamics, sensitivity to fabrication imperfections, dynamic instability, limited control resources - all these raise a number of fundamentally challenging issues in the design, analysis, and control of micromachined gyroscopes. In this paper, we summarize principles of operation, review recent research and development efforts, and discuss potential applications and the future market of silicon based micromachined gyroscopes.

  1. Silicon Micromachining for Terahertz Component Development

    Science.gov (United States)

    Chattopadhyay, Goutam; Reck, Theodore J.; Jung-Kubiak, Cecile; Siles, Jose V.; Lee, Choonsup; Lin, Robert; Mehdi, Imran

    2013-01-01

    Waveguide component technology at terahertz frequencies has come of age in recent years. Essential components such as ortho-mode transducers (OMT), quadrature hybrids, filters, and others for high performance system development were either impossible to build or too difficult to fabricate with traditional machining techniques. With micromachining of silicon wafers coated with sputtered gold it is now possible to fabricate and test these waveguide components. Using a highly optimized Deep Reactive Ion Etching (DRIE) process, we are now able to fabricate silicon micromachined waveguide structures working beyond 1 THz. In this paper, we describe in detail our approach of design, fabrication, and measurement of silicon micromachined waveguide components and report the results of a 1 THz canonical E-plane filter.

  2. Pro Spring Batch

    CERN Document Server

    Minella, Michael T

    2011-01-01

    Since its release, Spring Framework has transformed virtually every aspect of Java development including web applications, security, aspect-oriented programming, persistence, and messaging. Spring Batch, one of its newer additions, now brings the same familiar Spring idioms to batch processing. Spring Batch addresses the needs of any batch process, from the complex calculations performed in the biggest financial institutions to simple data migrations that occur with many software development projects. Pro Spring Batch is intended to answer three questions: *What? What is batch processing? What

  3. 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.

  4. Micromachined glass chips for ion analysis

    NARCIS (Netherlands)

    Gardeniers, Johannes G.E.; Mulder, Micha; Lüttge, Regina; van den Berg, Albert

    2002-01-01

    This article describes recent developments at Micronit Microfluidics B.V. and MESA+ in the field of "Lab-on-a-chip" systems for ion analysis. Glass chips with typical micromachined channel geometries for capillary electrophoresis and integrated conductivity detection were developed, with which

  5. Process optimization of batch biosorption of lead using Lactobacillius bulgaricus in an aqueous phase system using response surface methodology.

    Science.gov (United States)

    Sedighi, Mehdi; Ghasemi, Mostafa; Hassan, Sedky H A; Daud, Wan Ramli Wan; Ismail, Manal; Abdallah, Elgorban

    2012-05-01

    Response surface methodology (RSM) based on central composite rotatable design was used to investigate the effects of operating variable, mainly, pH, weight of biomass, and initial lead ion concentration on the lead adsorption capacity at ambient temperature using dried cells of Lactobacillius bulgaricus. Using RSM, quadratic polynomial equation was obtained for predicting the percent of lead ion removal. Analysis of variance showed that the effects of pH and weight of dried biomass were concluded to be the key factors influencing the capacity of lead ion removal. At pH lower than 2 (high acidic condition) and in alkaline condition, there is no significant biosorption. The optimum percent of lead ion removal was found at pH of 6.78, biomass concentration of 6.58 g/l and initial lead concentration 36.22 ppm. In this condition, percent of lead ion removal was 86.21%. This study showed RSM effectiveness for modeling of biosorption process.

  6. Influence of micromachined targets on laser accelerated proton beam profiles

    Science.gov (United States)

    Dalui, Malay; Permogorov, Alexander; Pahl, Hannes; Persson, Anders; Wahlström, Claes-Göran

    2018-03-01

    High intensity laser-driven proton acceleration from micromachined targets is studied experimentally in the target-normal-sheath-acceleration regime. Conical pits are created on the front surface of flat aluminium foils of initial thickness 12.5 and 3 μm using series of low energy pulses (0.5–2.5 μJ). Proton acceleration from such micromachined targets is compared with flat foils of equivalent thickness at a laser intensity of 7 × 1019 W cm‑2. The maximum proton energy obtained from targets machined from 12.5 μm thick foils is found to be slightly lower than that of flat foils of equivalent remaining thickness, and the angular divergence of the proton beam is observed to increase as the depth of the pit approaches the foil thickness. Targets machined from 3 μm thick foils, on the other hand, show evidence of increasing the maximum proton energy when the depths of the structures are small. Furthermore, shallow pits on 3 μm thick foils are found to be efficient in reducing the proton beam divergence by a factor of up to three compared to that obtained from flat foils, while maintaining the maximum proton energy.

  7. Micromachining of AlN and Al2O3 Using Fiber Laser

    Directory of Open Access Journals (Sweden)

    Florian Preusch

    2014-11-01

    Full Text Available We report on high precision high speed micromachining of Al2O3 and AlN using pulsed near infrared fiber laser. Ablation thresholds are determined to be 30 J/cm2 for alumina and 18 J/cm2 for aluminum nitride. The factors influencing the efficiency and quality of 3D micromachining, namely the surface roughness, the material removal rate and the ablation depth accuracy are determined as a function of laser repetition rate and pulse overlap. Using a fluence of 64 J/cm², we achieve a material removal rate of up to 94 mm³/h in Al2O3 and 135 mm³/h in AlN for high pulse overlaps (89% and 84%. A minimum roughness of 1.5 μm for alumina and 1.65 μm for aluminum nitride can be accomplished for medium pulse overlaps (42% to 56%. In addition, ablation depth deviation of the micromachining process of smaller than 8% for alumina and 2% for aluminum nitride are achieved. Based on these results, by structuring exemplarily 3D structures we demonstrate the potential of high quality and efficient 3D micromachining using pulsed fiber laser.

  8. 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.

  9. 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.

  10. Model Design of Piezoelectric Micromachined Modal Gyroscope

    Directory of Open Access Journals (Sweden)

    Xiaojun Hu

    2011-01-01

    Full Text Available This paper reports a novel kind of solid-state microgyroscope, which is called piezoelectric micromachined modal gyroscope (PMMG. PMMG has large stiffness and robust resistance to shake and strike because there is no evident mass-spring component in its structure. This work focused on quantitative optimization of the gyroscope, which is still blank for such gyroscope. The modal analysis by the finite element method (FEM was firstly conducted. A set of quantitative indicators were developed to optimize the operation mode. By FEM, the harmonic analysis was conducted to find the way to efficiently actuate the operational mode needed. The optimal configuration of driving electrodes was obtained. At last, the Coriolis analysis was conducted to show the relation between angular velocity and differential output voltage by the Coriolis force under working condition. The results obtained in this paper provide theoretical basis for realizing this novel kind of micromachined gyroscope.

  11. Micromachined Parts Advance Medicine, Astrophysics, and More

    Science.gov (United States)

    2015-01-01

    In the mid-1990s, Marshall Space Flight Center awarded two SBIR contracts to Potomac Photonics, now based in Baltimore, for the development of computerized workstations capable of mass-producing tiny, intricate, diffractive optical elements. While the company has since discontinued the workstations, those contracts set the stage for Potomac Photonics to be a leader in the micromachining industry, where NASA remains one of its clients.

  12. Micromachined Piezoelectric Actuators for Cryogenic Adaptive Optics, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — TRS Technologies proposes micromachined single crystal piezoelectric actuator arrays to enable ultra-large stroke, high precision shape control for large aperture,...

  13. In-pipe micromachine locomotion via the inertial stepping principle

    Energy Technology Data Exchange (ETDEWEB)

    Yum, Young Jin [University of Ulsan, Ulsan (Korea, Republic of); Hwang, Han Sub [Suweon Science College, Suweon (Korea, Republic of); Kelemen, Michal; Maxim, Vladislav; Frankovsky, Peter [Technical University of Kosice, Kosice (Slovakia)

    2014-08-15

    This paper discusses an in-pipe inspection micromachine intended for locomotion inside a small diameter pipe. The micromachine locomotion is based on the inertial stepping principle, which utilizes the drive force of the two-body impact. The in-pipe micromachine contacts the pipe through the elastic bristles installed on the in-pipe machine and in two lines and crossways with respect to the micromachine axle. The paper describes the principle of locomotion and the dynamics by which the unknown of both the parameters and the relations are experimentally identified. Based on the results, a simulation model was created, and the results of the simulations were compared with experimental results.

  14. Response surface modeling and optimization of chromium(VI) removal from aqueous solution using Tamarind wood activated carbon in batch process.

    Science.gov (United States)

    Sahu, J N; Acharya, Jyotikusum; Meikap, B C

    2009-12-30

    The present paper discusses response surface methodology (RSM) as an efficient approach for predictive model building and optimization of chromium adsorption on developed activated carbon. In this work the application of RSM is presented for optimizing the removal of Cr(VI) ions from aqua solutions using activated carbon as adsorbent. All experiments were performed according to statistical designs in order to develop the predictive regression models used for optimization. The optimization of adsorption of chromium on activated carbon was carried out to ensure a high adsorption efficiency at low adsorbent dose and high initial concentration of Cr(VI). While the goal of adsorption of chromium optimization was to improve adsorption conditions in batch process, i.e., to minimize the adsorbent dose and to increase the initial concentration of Cr(VI). In the adsorption experiments a laboratory developed Tamarind wood activated carbon made of chemical activation (zinc chloride) was used. A 2(4) full factorial central composite design experimental design was employed. Analysis of variance (ANOVA) showed a high coefficient of determination value (R(2)=0.928) and satisfactory prediction second-order regression model was derived. Maximum chromium removal efficiency was predicted and experimentally validated. The optimum adsorbent dose, temperature, initial concentration of Cr(VI) and initial pH of the Cr(VI) solution were found to be 4.3g/l, 32 degrees C, 20.15 mg/l and 5.41 respectively. Under optimal value of process parameters, high removal (>89%) was obtained for Cr(VI).

  15. Long-term effects of CuO nanoparticles on the surface physicochemical properties of biofilms in a sequencing batch biofilm reactor.

    Science.gov (United States)

    Hou, Jun; You, Guoxiang; Xu, Yi; Wang, Chao; Wang, Peifang; Miao, Lingzhan; Li, Yi; Ao, Yanhui; Lv, Bowen; Yang, Yangyang

    2016-11-01

    In this study, we examined the long-term effects of copper oxide nanoparticles (CuO NPs) on the production and properties of EPS and the resulting variations in surface physicochemical characteristics of biofilms in a sequencing batch biofilm reactor. After exposure to 50 mg/L CuO NPs for 45 days, the protein (PRO) and polysaccharide (PS) contents in loosely bound EPS (LB-EPS) decreased as the production of LB-EPS decreased from 34.4 to 30 mg TOC/g EPS. However, the production of tightly bound EPS (TB-EPS) increased by 16.47 % as the PRO and PS contents increased. The content of humic-like substances (HS) increased significantly, becoming the predominant constituent in EPS with the presence of 50 mg/L CuO NPs. Furthermore, the results of three-dimensional excitation-emission fluorescence spectra confirmed the various changes in terms of the LB-EPS and TB-EPS contents after exposure to CuO NPs. Fourier transform infrared spectroscopy showed that the -OH and -NH 2 groups of proteins in EPS were involved in the reaction with CuO NPs. Moreover, the chronic exposure to CuO NPs induced a negative impact on the flocculating efficiency of EPS and on the hydrophobicity and aggregation ability of microbial cells. The PRO/PS ratios of different EPS fractions were consistent with their hydrophobicities (R 2 >0.98) and bioflocculating efficiencies (R 2 >0.95); however, there was no correlation with aggregation ability. Additionally, the presence of bovine serum albumin (BSA) prevented the physical contact between CuO NPs and EPS as a result of NP aggregation and electrostatic repulsion.

  16. Spring batch essentials

    CERN Document Server

    Rao, P Raja Malleswara

    2015-01-01

    If you are a Java developer with basic knowledge of Spring and some experience in the development of enterprise applications, and want to learn about batch application development in detail, then this book is ideal for you. This book will be perfect as your next step towards building simple yet powerful batch applications on a Java-based platform.

  17. Solid polymer electrolyte composite membrane comprising laser micromachined porous support

    Science.gov (United States)

    Liu, Han [Waltham, MA; LaConti, Anthony B [Lynnfield, MA; Mittelsteadt, Cortney K [Natick, MA; McCallum, Thomas J [Ashland, MA

    2011-01-11

    A solid polymer electrolyte composite membrane and method of manufacturing the same. According to one embodiment, the composite membrane comprises a rigid, non-electrically-conducting support, the support preferably being a sheet of polyimide having a thickness of about 7.5 to 15 microns. The support has a plurality of cylindrical pores extending perpendicularly between opposing top and bottom surfaces of the support. The pores, which preferably have a diameter of about 5 microns, are made by laser micromachining and preferably are arranged in a defined pattern, for example, with fewer pores located in areas of high membrane stress and more pores located in areas of low membrane stress. The pores are filled with a first solid polymer electrolyte, such as a perfluorosulfonic acid (PFSA) polymer. A second solid polymer electrolyte, which may be the same as or different than the first solid polymer electrolyte, may be deposited over the top and/or bottom of the first solid polymer electrolyte.

  18. Resonant gravimetric immuno sensing based on capacitive micromachined ultrasound transducers

    International Nuclear Information System (INIS)

    Virzonis, Darius; Gailius Vanagas; Dovydas Barauskas; Ramanaviciene, Almira; Makaraviciute, Asta; Ramanavicius, Arunas; Wen, Weijia; Kodzius, Rimantas

    2014-01-01

    High-frequency (40 MHz) and low-frequency (7 MHz) capacitive micromachined ultrasound transducers (CMUT) were fabricated and tested for use in gravimetric detection of biomolecules. The low-frequency CMUT sensors have a gold-coated surface, while the high-frequency sensors have a silicon nitride surface. Both surfaces were functionalized with bovine leukemia virus antigen gp51 acting as the antigen. On addition of an a specific antibody labeled with horseradish peroxidase (HRP), the antigen/antibody complex is formed on the surface and quantified by HRP-catalyzed oxidation of tetramethylbenzidine. It has been found that a considerably smaller quantity of immuno complex is formed on the high frequency sensor surface. In parallel, the loading of the surface of the CMUT was determined via resonance frequency and electromechanical resistance readings. Following the formation of the immuno complexes, the resonance frequencies of the low-frequency and high-frequency sensors decrease by up to 420 and 440 kHz, respectively. Finite element analysis reveals that the loading of the (gold-coated) low frequency sensors is several times larger than that on high frequency sensors. The formation of the protein film with pronounced elasticity and stress on the gold surface case is discussed. We also discuss the adoption of this method for the detection of DNA using a hybridization assay following polymerase chain reaction. (author)

  19. Resonant gravimetric immunosensing based on capacitive micromachined ultrasound transducers

    KAUST Repository

    Viržonis, Darius

    2014-04-08

    High-frequency (40 MHz) and low-frequency (7 MHz) capacitive micromachined ultrasound transducers (CMUT) were fabricated and tested for use in gravimetric detection of biomolecules. The low-frequency CMUT sensors have a gold-coated surface, while the high-frequency sensors have a silicon nitride surface. Both surfaces were functionalized with bovine leukemia virus antigen gp51 acting as the antigen. On addition of an a specific antibody labeled with horseradish peroxidase (HRP), the antigen/antibody complex is formed on the surface and quantified by HRP-catalyzed oxidation of tetramethylbenzidine. It has been found that a considerably smaller quantity of immuno complex is formed on the high frequency sensor surface. In parallel, the loading of the surface of the CMUT was determined via resonance frequency and electromechanical resistance readings. Following the formation of the immuno complexes, the resonance frequencies of the low-frequency and high-frequency sensors decrease by up to 420 and 440 kHz, respectively. Finite element analysis reveals that the loading of the (gold-coated) low frequency sensors is several times larger than that on high frequency sensors. The formation of the protein film with pronounced elasticity and stress on the gold surface case is discussed. We also discuss the adoption of this method for the detection of DNA using a hybridization assay following polymerase chain reaction.

  20. Advanced technology trend survey of micromachines in Europe; Oshu ni okeru micromachine sentan gijutsu doko chosa

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-02-01

    In this research survey, the development trend of micromachine technology in Europe was surveyed, development level of micromachine technology of European companies was grasped, and practical application fields of their target were investigated. Technology development level of private companies in Japan`s national projects and practical application fields of Japan`s target were arranged. Trends of micromachine technology development are compared between Japanese companies and European companies. Among micromachine technology development projects in Europe, ``8520 MUST`` is a part of the ESPRIT Project. About 40,000 companies among about 170,000 companies in whole Europe are relating to the MUST Project. The main fields include the manufacturing technology, process control of machines, technology of safety, sensor technology in environmental fields, and automotive technology. The marketing fields of application include the automobile, military technology, home automation, industrial process, medical technology, environmental technology, and games. The results can be compared with the direction of research and development in Japan. 22 figs., 8 tabs.

  1. Optofluidic Microlasers based on Femtosecond Micromachining Technology

    Directory of Open Access Journals (Sweden)

    Simoni F.

    2017-08-01

    Full Text Available We present the different optofluidic lasers which have been realized using the Femtosecond Micromachining technique to fabricate the monolithic optofluidic structures in glass chips. We show how the great flexibility of this 3D technique allows getting different kind of optical cavities. The most recent devices fabricated by this technique as ring shaped and Fabry-Perot resonators show excellent emission performances.We also point out how the addition of the inkjet printing technique provides further opportunities in realizing optofluidic chips.

  2. SPS batch spacing optimisation

    CERN Document Server

    Velotti, F M; Carlier, E; Goddard, B; Kain, V; Kotzian, G

    2017-01-01

    Until 2015, the LHC filling schemes used the batch spac-ing as specified in the LHC design report. The maximumnumber of bunches injectable in the LHC directly dependson the batch spacing at injection in the SPS and hence onthe MKP rise time.As part of the LHC Injectors Upgrade project for LHCheavy ions, a reduction of the batch spacing is needed. In thisdirection, studies to approach the MKP design rise time of150ns(2-98%) have been carried out. These measurementsgave clear indications that such optimisation, and beyond,could be done also for higher injection momentum beams,where the additional slower MKP (MKP-L) is needed.After the successful results from 2015 SPS batch spacingoptimisation for the Pb-Pb run [1], the same concept wasthought to be used also for proton beams. In fact, thanksto the SPS transverse feed back, it was already observedthat lower batch spacing than the design one (225ns) couldbe achieved. For the 2016 p-Pb run, a batch spacing of200nsfor the proton beam with100nsbunch spacing wasreque...

  3. Flexure-beam micromirror devices and potential expansion for smart micromachining

    Science.gov (United States)

    Lin, Tseng-Hwang

    1996-05-01

    Texas Instruments has been developing both digital and analog micromirror devices since the late 1970s. The analog flexure-beam micromirror devices are primarily targeted for imaging identification. Digital multiplexing mechanisms are used in column and row selection to address discretized analog signals into the array. Amplifiers and sample-and-hold circuits provide the appropriate signal range to control the micromirrors. Analog-to-digital and digital- to-analog conversions are currently built into the interface electronics, and will potentially be built into the chip. The micromirror devices are built on the top of the addressing circuits using sacrificial layers and two different metal layers. This concept of surface micromachining and mixed-signal circuit integration enables us to investigate the possibility of smart micromachining. Micromirror device applications can expand beyond optical applications into microsensor and other microactuator areas. The addressing circuits can be used in the interface of analog real-world and smart control circuits.

  4. Fabrication of three-dimensional microdisk resonators in calcium fluoride by femtosecond laser micromachining

    Science.gov (United States)

    Lin, Jintian; Xu, Yingxin; Tang, Jialei; Wang, Nengwen; Song, Jiangxin; He, Fei; Fang, Wei; Cheng, Ya

    2014-09-01

    We report on fabrication of on-chip calcium fluoride (CaF2) microdisk resonators using water-assisted femtosecond laser micromachining. Focused ion beam (FIB) milling is used to create ultra-smooth sidewalls. The quality ( Q) factors of the fabricated microresonators are measured to be 4.2 × 104 at wavelengths near 1,550 nm. The Q factor is mainly limited by the scattering from the bottom surface of the disk whose roughness remains high due to the femtosecond laser micromachining process. This technique facilitates the formation of on-chip microresonators on various kinds of bulk crystalline materials, which can benefit a wide range of applications such as nonlinear optics, quantum optics, and chip-level integration of photonic devices.

  5. Batch-to-batch model improvement for cooling crystallization

    OpenAIRE

    Forgione , Marco; Birpoutsoukis , Georgios; Bombois , Xavier; Mesbah , Ali; Daudey , Peter; Van Den Hof , Paul

    2015-01-01

    International audience; Two batch-to-batch model update strategies for model-based control of batch cooling crystallization are presented. In Iterative Learning Control, a nominal process model is adjusted by a non-parametric, additive correction term which depends on the difference between the measured output and the model prediction in the previous batch. In Iterative Identification Control, the uncertain model parameters are iteratively estimated using the measured batch data. Due to the d...

  6. Application of response surface methodology to study the biological removal of nitrogen from effluent of cattle slaughterhouse in a sequencing batch reactor

    OpenAIRE

    Lima,Adriana N. de; Gomes,Benedito M.; Gomes,Simone D.; Carvalho,Karina Q. de; Christ,Divair

    2014-01-01

    The aim of this study was to evaluate the efficiency of a sequencing batch reactor (SBR) on biological removal of nitrogen from cattle slaughterhouse wastewater by nitrification/denitrification processes. The effects of initial concentration of ammoniacal nitrogen were investigated at 100; 150 and 200 mg L-1 and air flow rate at 0.125; 0.375 and 0.625 L min¹ Lreactor-1 on the nitrogen compounds removal, by a Central Composite Rotational Design (CCRD) configuration. There were variations from ...

  7. Fiber laser micromachining of magnesium alloy tubes for biocompatible and biodegradable cardiovascular stents

    Science.gov (United States)

    Demir, Ali Gökhan; Previtali, Barbara; Colombo, Daniele; Ge, Qiang; Vedani, Maurizio; Petrini, Lorenza; Wu, Wei; Biffi, Carlo Alberto

    2012-02-01

    Magnesium alloys constitute an attractive solution for cardiovascular stent applications due to their intrinsic properties of biocompatibility and relatively low corrosion resistance in human-body fluids, which results in as a less intrusive treatment. Laser micromachining is the conventional process used to cut the stent mesh, which plays the key role for the accurate reproduction of the mesh design and the surface quality of the produced stent that are important factors in ensuring the mechanical and corrosion resistance properties of such a kind of devices. Traditionally continuous or pulsed laser systems working in microsecond pulse regime are employed for stent manufacturing. Pulsed fiber lasers on the other hand, are a relatively new solution which could balance productivity and quality aspects with shorter ns pulse durations and pulse energies in the order of mJ. This work reports the study of laser micromachining and of AZ31 magnesium alloy for the manufacturing of cardiovascular stents with a novel mesh design. A pulsed active fiber laser system operating in nanosecond pulse regime was employed for the micromachining. Laser parameters were studied for tubular cutting on a common stent material, AISI 316L tubes with 2 mm in diameter and 0.2 mm in thickness and on AZ31 tubes with 2.5 mm in diameter and 0.2 in thickness. In both cases process parameters conditions were examined for reactive and inert gas cutting solutions and the final stent quality is compared.

  8. 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.

  9. Heuristics for batching and sequencing in batch processing machines

    Directory of Open Access Journals (Sweden)

    Chuda Basnet

    2016-12-01

    Full Text Available In this paper, we discuss the “batch processing” problem, where there are multiple jobs to be processed in flow shops. These jobs can however be formed into batches and the number of jobs in a batch is limited by the capacity of the processing machines to accommodate the jobs. The processing time required by a batch in a machine is determined by the greatest processing time of the jobs included in the batch. Thus, the batch processing problem is a mix of batching and sequencing – the jobs need to be grouped into distinct batches, the batches then need to be sequenced through the flow shop. We apply certain newly developed heuristics to the problem and present computational results. The contributions of this paper are deriving a lower bound, and the heuristics developed and tested in this paper.

  10. Micromachined Ultrasonic Transducers for 3-D Imaging

    DEFF Research Database (Denmark)

    Christiansen, Thomas Lehrmann

    of state-of-the-art 3-D ultrasound systems. The focus is on row-column addressed transducer arrays. This previously sparsely investigated addressing scheme offers a highly reduced number of transducer elements, resulting in reduced transducer manufacturing costs and data processing. To produce...... such transducer arrays, capacitive micromachined ultrasonic transducer (CMUT) technology is chosen for this project. Properties such as high bandwidth and high design flexibility makes this an attractive transducer technology, which is under continuous development in the research community. A theoretical...... capable of producing 62+62-element row-column addressed CMUT arrays with negligible charging issues. The arrays include an integrated apodization, which reduces the ghost echoes produced by the edge waves in such arrays by 15:8 dB. The acoustical cross-talk is measured on fabricated arrays, showing a 24 d...

  11. MEASUREMENT OF NANOSTRUCTURES WITH MICROMACHINED MICROSCOPES

    Energy Technology Data Exchange (ETDEWEB)

    G.S. KINO; W.E. MOERNER

    2005-04-30

    We have made reproducible scanning probes with high efficiency, and predictable and reproducible character-istics. We obtained good efficiency with dimensions well below the diffraction limit, so that rela-tively small laser powers in the milliwatt range can be used. For single frequency operation, only low power is necessary to obtain very high fields for the excitation of well-defined Raman scattering, and to work in a reflection mode with good scanning speeds; obtained predictable results with very high fields suitable for obtaining Raman scattering and two-photon scattering; made a scanning probe mounted on a micromachined cantilever to obtain high definition reflection mode images that can be scanned rapidly;and observed Raman scattering using bowtie antennas with CW excitation.

  12. Micromachined two dimensional resistor arrays for determination of gas parameters

    NARCIS (Netherlands)

    van Baar, J.J.J.; Verwey, Willem B.; Dijkstra, Mindert; Dijkstra, Marcel; Wiegerink, Remco J.; Lammerink, Theodorus S.J.; Krijnen, Gijsbertus J.M.; Elwenspoek, Michael Curt

    A resistive sensor array is presented for two dimensional temperature distribution measurements in a micromachined flow channel. This allows simultaneous measurement of flow velocity and fluid parameters, like thermal conductivity, diffusion coefficient and viscosity. More general advantages of

  13. Structure optimization and simulation analysis of the quartz micromachined gyroscope

    Directory of Open Access Journals (Sweden)

    Xuezhong Wu

    2014-02-01

    Full Text Available Structure optimization and simulation analysis of the quartz micromachined gyroscope are reported in this paper. The relationships between the structure parameters and the frequencies of work mode were analysed by finite element analysis. The structure parameters of the quartz micromachined gyroscope were optimized to reduce the difference between the frequencies of the drive mode and the sense mode. The simulation results were proved by testing the prototype gyroscope, which was fabricated by micro-electromechanical systems (MEMS technology. Therefore, the frequencies of the drive mode and the sense mode can match each other by the structure optimization and simulation analysis of the quartz micromachined gyroscope, which is helpful in the design of the high sensitivity quartz micromachined gyroscope.

  14. Integration of Capacitive Micromachined Ultrasound Transducers to Microfluidic Devices

    KAUST Repository

    Viržonis, Darius

    2013-10-22

    The design and manufacturing flexibility of capacitive micromachined ultrasound transducers (CMUT) makes them attractive option for integration with microfluidic devices both for sensing and fluid manipulation. CMUT concept is introduced here by presentin

  15. Biasing of Capacitive Micromachined Ultrasonic Transducers.

    Science.gov (United States)

    Caliano, Giosue; Matrone, Giulia; Savoia, Alessandro Stuart

    2017-02-01

    Capacitive micromachined ultrasonic transducers (CMUTs) represent an effective alternative to piezoelectric transducers for medical ultrasound imaging applications. They are microelectromechanical devices fabricated using silicon micromachining techniques, developed in the last two decades in many laboratories. The interest for this novel transducer technology relies on its full compatibility with standard integrated circuit technology that makes it possible to integrate on the same chip the transducers and the electronics, thus enabling the realization of extremely low-cost and high-performance devices, including both 1-D or 2-D arrays. Being capacitive transducers, CMUTs require a high bias voltage to be properly operated in pulse-echo imaging applications. The typical bias supply residual ripple of high-quality high-voltage (HV) generators is in the millivolt range, which is comparable with the amplitude of the received echo signals, and it is particularly difficult to minimize. The aim of this paper is to analyze the classical CMUT biasing circuits, highlighting the features of each one, and to propose two novel HV generator architectures optimized for CMUT biasing applications. The first circuit proposed is an ultralow-residual ripple (CMUT by charging a buffer capacitor synchronously with the pulsing sequence, thus reducing the impact of the switching noise on the received echo signals. The small area of the circuit (about 1.5 cm 2 ) makes it possible to generate the bias voltage inside the probe, very close to the CMUT, making the proposed solution attractive for portable applications. Measurements and experiments are shown to demonstrate the effectiveness of the new approaches presented.

  16. Development of a Novel Transparent Flexible Capacitive Micromachined Ultrasonic Transducer.

    Science.gov (United States)

    Pang, Da-Chen; Chang, Cheng-Min

    2017-06-20

    This paper presents the world's first transparent flexible capacitive micromachined ultrasonic transducer (CMUT) that was fabricated through a roll-lamination technique. This polymer-based CMUT has advantages of transparency, flexibility, and non-contacting detection which provide unique functions in display panel applications. Comprising an indium tin oxide-polyethylene terephthalate (ITO-PET) substrate, SU-8 sidewall and vibrating membranes, and silver nanowire transparent electrode, the transducer has visible-light transmittance exceeding 80% and can operate on curved surfaces with a 40 mm radius of curvature. Unlike the traditional silicon-based high temperature process, the CMUT can be fabricated on a flexible substrate at a temperature below 100 °C to reduce residual stress introduced at high temperature. The CMUT on the curved surfaces can detect a flat target and finger at distances up to 50 mm and 40 mm, respectively. The transparent flexible CMUT provides a better human-machine interface than existing touch panels because it can be integrated with a display panel for non-contacting control in a health conscious environment and the flexible feature is critical for curved display and wearable electronics.

  17. Development of a Novel Transparent Flexible Capacitive Micromachined Ultrasonic Transducer

    Directory of Open Access Journals (Sweden)

    Da-Chen Pang

    2017-06-01

    Full Text Available This paper presents the world’s first transparent flexible capacitive micromachined ultrasonic transducer (CMUT that was fabricated through a roll-lamination technique. This polymer-based CMUT has advantages of transparency, flexibility, and non-contacting detection which provide unique functions in display panel applications. Comprising an indium tin oxide-polyethylene terephthalate (ITO-PET substrate, SU-8 sidewall and vibrating membranes, and silver nanowire transparent electrode, the transducer has visible-light transmittance exceeding 80% and can operate on curved surfaces with a 40 mm radius of curvature. Unlike the traditional silicon-based high temperature process, the CMUT can be fabricated on a flexible substrate at a temperature below 100 °C to reduce residual stress introduced at high temperature. The CMUT on the curved surfaces can detect a flat target and finger at distances up to 50 mm and 40 mm, respectively. The transparent flexible CMUT provides a better human-machine interface than existing touch panels because it can be integrated with a display panel for non-contacting control in a health conscious environment and the flexible feature is critical for curved display and wearable electronics.

  18. Prunus dulcis, Batch

    African Journals Online (AJOL)

    STORAGESEVER

    2010-06-07

    Jun 7, 2010 ... almond (Prunus dulcis, Batch) genotypes as revealed by PCR analysis. Yavar Sharafi1*, Jafar Hajilou1, Seyed AbolGhasem Mohammadi2, Mohammad Reza Dadpour1 and Sadollah Eskandari3. 1Department of Horticulture, Faculty of Agriculture, University of Tabriz, Tabriz, 5166614766, Iran.

  19. Non-traditional micromachining processes fundamentals and applications

    CERN Document Server

    Bhattacharyya, B; Davim, J

    2017-01-01

    This book presents a complete coverage of micromachining processes from their basic material removal phenomena to past and recent research carried by a number of researchers worldwide. Chapters on effective utilization of material resources, improved efficiency, reliability, durability, and cost effectiveness of the products are presented. This book provides the reader with new and recent developments in the field of micromachining and microfabrication of engineering materials.

  20. In-fiber whispering-gallery-mode resonator fabricated by femtosecond laser micromachining.

    Science.gov (United States)

    Shi, Leilei; Zhu, Tao; Huang, Dongmei; Liu, Min; Deng, Ming; Huang, Wei

    2015-08-15

    An in-fiber whispering-gallery-mode resonator fabricated by femtosecond laser micromachining is demonstrated. The cylinder resonator cavity is fabricated by scanning the D-fiber cladding with infrared femtosecond pulses along a cylindrical trace with a radius of 25 μm and height of 20 μm. Quality factor on the order of 10(3) is achieved by smoothing the cavity surface with an ultrasonic cleaner, which is mainly limited by the surface roughness of several hundred nanometers. Resonant characteristics and polarization dependence of the proposed resonator are also studied in detail. Our method takes a step forward in the integration of whispering-gallery-mode resonators.

  1. Silicon micromachining using a high-density plasma source

    International Nuclear Information System (INIS)

    McAuley, S.A.; Ashraf, H.; Atabo, L.; Chambers, A.; Hall, S.; Hopkins, J.; Nicholls, G.

    2001-01-01

    Dry etching of Si is critical in satisfying the demands of the micromachining industry. The micro-electro-mechanical systems (MEMS) community requires etches capable of high aspect ratios, vertical profiles, good feature size control and etch uniformity along with high throughput to satisfy production requirements. Surface technology systems' (STS's) high-density inductively coupled plasma (ICP) etch tool enables a wide range of applications to be realized whilst optimizing the above parameters. Components manufactured from Si using an STS ICP include accelerometers and gyroscopes for military, automotive and domestic applications. STS's advanced silicon etch (ASE TM ) has also allowed the first generation of MEMS-based optical switches and attenuators to reach the marketplace. In addition, a specialized application for fabricating the next generation photolithography exposure masks has been optimized for 200 mm diameter wafers, to depths of ∼750 μm. Where the profile is not critical, etch rates of greater than 8 μm min -1 have been realized to replace previous methods such as wet etching. This is also the case for printer applications. Specialized applications that require etching down to pyrex or oxide often result in the loss of feature size control at the interface; this is an industry wide problem. STS have developed a technique to address this. The rapid progression of the industry has led to development of the STS ICP etch tool, as well as the process. (author)

  2. Exploitation of capacitive micromachined transducers for nonlinear ultrasound imaging.

    Science.gov (United States)

    Novell, Anthony; Legros, Mathieu; Felix, Nicolas; Bouakaz, Ayache

    2009-12-01

    Capacitive micromachined ultrasonic transducers (CMUTs) present advantages such as wide frequency bandwidth, which could be further developed for nonlinear imaging. However, the driving electrostatic force induces a nonlinear behavior of the CMUT, thus generating undesirable harmonic components in the generated acoustic signal. Consequently, the use of CMUT for harmonic imaging (with or without contrast agents) becomes challenging. This paper suggests 2 compensation approaches, linear and nonlinear methods, to cancel unwanted nonlinear components. Furthermore, nonlinear responses from contrast agent were evaluated using CMUT in transmit before and after compensation. The results were compared with those obtained using a PZT transducer in transmit. Results showed that CMUT nonlinear behavior is highly influenced by the excitation to bias voltage ratio. Measurements of output pressure very close to the CMUT surface allow the estimation of optimal parameters for each compensation approach. Both methods showed a harmonic reduction higher than 20 dB when one element or several elements are excited. In addition, the study demonstrates that nonlinear approach seems to be more efficient because it is shown to be less sensitive to interelement variability and further avoids fundamental component deterioration. The results from contrast agent measurements showed that the responses obtained using CMUT elements in transmit with compensation were similar to those from PZT transducer excitation. This experimental study demonstrates the opportunity to use CMUT with traditional harmonic contrast imaging techniques.

  3. 3DX: a micromachined silicon crystallographic x-ray detector

    Science.gov (United States)

    Morse, John; Kenney, Christopher J.; Westbrook, Edwin M.; Naday, Istvan; Parker, Sherwood I.

    2003-01-01

    We are developing pixel detectors for macromolecular crystallography, in which diffracted X-rays are directly absorbed by high-resistivity, crystalline silicon that has been micro-machined by inductively-coupled plasma etching. Arrays of 64 × 64 holes at 150 μm pitch are first formed by etching through the entire silicon bulk, then backfilled with polysilicon that is doped to create conducting p and n type columnar electrodes. When reverse biased, these electrodes generate electric fields that define the individual pixels. By forming conducting polysilicon on the sides of the sensors, which are cut-out of the silicon wafer by plasma etching, the entire surface of the detector may be made active. CMOS readout integrated circuits are conductively bump bonded behind each 3D detector, providing a direct connection to every pixel. A large array will be assembled with no insensitive bands along the edges by overlapping these sensors, each of area 0.96cm2. This detector will measure X-ray signal intensities of up to 105 events/pixel/sec without any pile-up loss, by using an integration method that retains the benefits of discrete photon counting. The detector sensitivity will be highly uniform, it will not exhibit any dark signal or spurious noise, and no geometric distortion will occur within each sensor.

  4. Modelling of Batch Process Operations

    DEFF Research Database (Denmark)

    Abdul Samad, Noor Asma Fazli; Cameron, Ian; Gani, Rafiqul

    2011-01-01

    Here a batch cooling crystalliser is modelled and simulated as is a batch distillation system. In the batch crystalliser four operational modes of the crystalliser are considered, namely: initial cooling, nucleation, crystal growth and product removal. A model generation procedure is shown that s...

  5. Predictive modeling, simulation, and optimization of laser processing techniques: UV nanosecond-pulsed laser micromachining of polymers and selective laser melting of powder metals

    Science.gov (United States)

    Criales Escobar, Luis Ernesto

    One of the most frequently evolving areas of research is the utilization of lasers for micro-manufacturing and additive manufacturing purposes. The use of laser beam as a tool for manufacturing arises from the need for flexible and rapid manufacturing at a low-to-mid cost. Laser micro-machining provides an advantage over mechanical micro-machining due to the faster production times of large batch sizes and the high costs associated with specific tools. Laser based additive manufacturing enables processing of powder metals for direct and rapid fabrication of products. Therefore, laser processing can be viewed as a fast, flexible, and cost-effective approach compared to traditional manufacturing processes. Two types of laser processing techniques are studied: laser ablation of polymers for micro-channel fabrication and selective laser melting of metal powders. Initially, a feasibility study for laser-based micro-channel fabrication of poly(dimethylsiloxane) (PDMS) via experimentation is presented. In particular, the effectiveness of utilizing a nanosecond-pulsed laser as the energy source for laser ablation is studied. The results are analyzed statistically and a relationship between process parameters and micro-channel dimensions is established. Additionally, a process model is introduced for predicting channel depth. Model outputs are compared and analyzed to experimental results. The second part of this research focuses on a physics-based FEM approach for predicting the temperature profile and melt pool geometry in selective laser melting (SLM) of metal powders. Temperature profiles are calculated for a moving laser heat source to understand the temperature rise due to heating during SLM. Based on the predicted temperature distributions, melt pool geometry, i.e. the locations at which melting of the powder material occurs, is determined. Simulation results are compared against data obtained from experimental Inconel 625 test coupons fabricated at the National

  6. Removal of 1,2-Dichloroethane from real industrial wastewater using a sub-surface batch system with Typha angustifolia L.

    Science.gov (United States)

    Al-Baldawi, Israa Abdulwahab

    2018-01-01

    1,2-Dichloroethane (1,2-DCA) is widely present in urban wastewaters and can be remediated by green technology. Subsurface batch system constructed wetlands (SSCWs) using macrophyte species of T. angustifolia L. were examined to remove 1,2-DCA using real wastewater from a petrochemical industry with a 1,2-DCA concentration of 390mg/L. We conducted an experiment with four pilot-scale constructed wetlands (0.81m 2 ) in a greenhouse. Three SSCWs (T2, T3 and T4) were fed with real wastewater, and another one (T1) was fed with tap water (as plant control) to assess the role of T. angustifolia L. and their associated rhizobacteria to remediate 1,2-DCA. Tank T2 contained only sand without plants acting as contaminant control, tank T3 contained sand with plants and finally tank T4 contained plants with mixture of sand, soil and compost (3:2:1). The results show that the green technology has improved the removal of 1,2-DCA from the contaminated water through biodegradation with a remediation efficiency of 100% in T4 within 42 days. The removal efficiency was enhanced in T4 with 18% more than in T3 due to the compost addition, giving evidence for the potential application of SSCWs to treat chlorinated hydrocarbon in real field. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Molecular-Scale Lubricants for Micromachine Applications: Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Burns, A.R.; Dugger, M.T.; Houston, J.E.; Lopez, G.P.; Mayer, T.M.; Michalske, T.A.; Miller, S.L.; Sniegowski, J.J.; Stevens, M.J.; Zhou, Y.

    1998-12-01

    The nature of this work was to develop the physics and chemistry base for understanding molecular-scale lubricants used to reduce of friction- and adhesion-induced failure in silicon micromachines (MEMS). We acquired this new knowledge by tailoring the molecular properties of the lubricants, applying local probes that can directly monitor the response of lubricants in contact conditions, and evaluating the performance of model lubricants MEMS devices. Model lubricants under investigation were the silane coupling agents that form monolayer films on native oxide silicon surfaces, which is the substrate in MEMS. These molecules bind via strong surface bonds and produce a layer of hydro- or fluoro-carbon chains normal to the substrate. "Tailoring" the lubricants entails modifying the chain length, the chain chemical reactivity (H or F), and the density of chain structures. Thus much effort went into understanding the surface chemistry of silane-silicon oxide coupling. With proximal probes such as atomic force microscopy (AFM), interracial force microscopy (FM), and shear force microscopy in combination with IFM, we examined the frictional and adhesive properties of the silane films with very high spatial resolution (< 100 nm) and sensitivity. MEMS structures are treated with silanes under identical conditions, and examined for friction and adhesion under operating conditions. Proper assessment of the lubricants required quantitative analysis of MEMS performance at high speeds and long operating times. Our proximal probe measurements and WS performance analyses form a very important link for future molecular dynamics simulations, that, in turn, should be able to predict MEMS performance under all conditions.

  8. Silicon Micromachining in RF and Photonic Applications

    Science.gov (United States)

    Lin, Tsen-Hwang; Congdon, Phil; Magel, Gregory; Pang, Lily; Goldsmith, Chuck; Randall, John; Ho, Nguyen

    1995-01-01

    Texas Instruments (TI) has developed membrane and micromirror devices since the late 1970s. An eggcrate space membrane was used as the spatial light modulator in the early years. Discrete micromirrors supported by cantilever beams created a new era for micromirror devices. Torsional micromirror and flexure-beam micromirror devices were promising for mass production because of their stable supports. TI's digital torsional micromirror device is an amplitude modulator (known as the digital micromirror device (DMD) and is in production development, discussed elsewhere. We also use a torsional device for a 4 x 4 fiber-optic crossbar switch in a 2 cm x 2 cm package. The flexure-beam micromirror device is an analog phase modulator and is considered more efficient than amplitude modulators for use in optical processing systems. TI also developed millimeter-sized membranes for integrated optical switches for telecommunication and network applications. Using a member in radio frequency (RF) switch applications is a rapidly growing area because of the micromechanical device performance in microsecond-switching characteristics. Our preliminary membrane RF switch test structure results indicate promising speed and RF switching performance. TI collaborated with MIT for modeling of metal-based micromachining.

  9. Robust Design of an Optical Micromachine for an Ophthalmic Application

    Directory of Open Access Journals (Sweden)

    Ingo Sieber

    2016-05-01

    Full Text Available This article describes an approach to the robust design of an optical micromachine consisting of a freeform optics, an amplification linkage, and an actuator. The robust design approach consists of monolithic integration principles to minimize assembly efforts and of an optimization of the functional components with respect to robustness against remaining assembly and manufacturing tolerances. The design approach presented involves the determination of the relevant tolerances arising from the domains manufacturing, assembly, and operation of the micromachine followed by a sensitivity analysis with the objective of identifying the worst offender. Subsequent to the above-described steps, an optimization of the functional design of the freeform optics with respect to a compensation of the effects of the tolerances is performed. The result leads to a robust design of the freeform optics and hence ensures a defined and optimal minimum performance of the micromachine in the presence of tolerances caused by the manufacturing processes and the operation of the micromachine. The micromachine under discussion is the tunable optics of an ophthalmic implant, an artificial accommodation system recently realized as a demonstration model at a scale of 2:1. The artificial accommodation system will be developed to replace the human crystalline lens in the case of a cataract.

  10. Capacitive Micromachined Ultrasonic Transducers for Therapeutic Ultrasound Applications

    Science.gov (United States)

    Wong, Serena H.; Kupnik, Mario; Watkins, Ronald D.; Butts-Pauly, Kim; Khuri-Yakub, Butrus T.

    2014-01-01

    Therapeutic ultrasound guided by magnetic resonance imaging (MRI) is a noninvasive treatment that potentially reduces mortality, lowers medical costs, and widens accessibility of treatments for patients. Recent developments in the design and fabrication of capacitive micromachined ultrasonic transducers (CMUTs) have made them competitive with piezoelectric transducers for use in therapeutic ultrasound applications. In this paper, we present the first designs and prototypes of an 8-element, concentric-ring, CMUT array to treat upper abdominal cancers. This array was simulated and designed to focus 30–50 mm into tissue and ablate a 2–3 cm diameter tumor within 1 hour. Assuming a surface acoustic output pressure of 1 MPa peak to peak (8.5 W/cm2) at 2.5 MHz, we simulated an array that produced a focal intensity of 680 W/cm2 when focusing to 35 mm. CMUT cells were then designed to meet these frequency and surface acoustic intensity specifications. These cell designs were fabricated as 2.5 mm by 2.5 mm test transducers and used to verify our models. The test transducers were shown to operate at 2.5 MHz with an output pressure of 1.4 MPa peak to peak (16.3 W/cm2). With this CMUT cell design, we fabricated a full 8-element array. Due to yield issues, we only developed electronics to focus the four center elements of the array. The beam profile of the measured array deviated from the simulated because of crosstalk effects; the beamwidth matched within 10% and sidelobes increased by 2 times, which caused the measured gain to be 16.6 compared to 27.4. PMID:19628448

  11. Dual axis operation of a micromachined rate gyroscope

    Energy Technology Data Exchange (ETDEWEB)

    Juneau, T. [BSAC, Berkeley, CA (United States); Pisano, A.P. [Univ. California, Berkeley, CA (United States). Dept. of Mechanical Engineering; Smith, J. [Sandia National Lab., Albuquerque, NM (United States)

    1997-04-01

    Since micromachining technology has raised the prospect of fabricating high performance sensors without the associated high cost and large size, many researchers have investigated micromachined rate gyroscopes. The vast majority of research has focused on single input axis rate gyroscopes, but this paper presents work on a dual input axis micromachined rate gyroscope. The key to successful simultaneous dual axis operation is the quad symmetry of the circular oscillating rotor design. Untuned gyroscopes with mismatched modes yielded random walk as low as 10{degrees}/{radical}hour with cross sensitivity ranging from 6% to 16%. Mode frequency matching via electrostatic tuning allowed performance better than 2{degrees}/{radical}hour, but at the expense of excessive cross sensitivity.

  12. Development of Micromachine Gas Turbine for Portable Power Generation

    Science.gov (United States)

    Isomura, Kousuke; Tanaka, Shuji; Togo, Shinichi; Kanebako, Hideki; Murayama, Motohide; Saji, Nobuyoshi; Sato, Fumihiro; Esashi, Masayoshi

    Micromachine gas turbine with centrifugal impellers of 10mm diameter fabricated by 5-axis micro-milling is under development at Tohoku University, in conjunction with Ishikawajima-Harima Heavy Industries Co., Ltd. (IHI), Tohoku-Gakuin University, and Sankyo Seiki Mfg. Co., Ltd. The development is currently at the stage of proving the feasibility of the gas turbine cycle by component tests. Micro-combustors have been developed for both hydrogen and methane fuel. Over 99.9% of the combustion efficiency has been realized in both combustors and the baseline configuration of the combustor for the gas turbine is set. A compressor of 10mm diameter has been developed as a micromachined turbocharger. The performance test of the micromachined turbocharger has been started, and ran up to 566000rpm, which is approximately 65% of the design speed. Compressor performance has been successfully measured along a constant speed line at 55% of the design speed.

  13. Silicon bulk micromachined hybrid dimensional artifact.

    Energy Technology Data Exchange (ETDEWEB)

    Claudet, Andre A.; Tran, Hy D.; Bauer, Todd Marks; Shilling, Katherine Meghan; Oliver, Andrew David

    2010-03-01

    A mesoscale dimensional artifact based on silicon bulk micromachining fabrication has been developed and manufactured with the intention of evaluating the artifact both on a high precision coordinate measuring machine (CMM) and video-probe based measuring systems. This hybrid artifact has features that can be located by both a touch probe and a video probe system with a k=2 uncertainty of 0.4 {micro}m, more than twice as good as a glass reference artifact. We also present evidence that this uncertainty could be lowered to as little as 50 nm (k=2). While video-probe based systems are commonly used to inspect mesoscale mechanical components, a video-probe system's certified accuracy is generally much worse than its repeatability. To solve this problem, an artifact has been developed which can be calibrated using a commercially available high-accuracy tactile system and then be used to calibrate typical production vision-based measurement systems. This allows for error mapping to a higher degree of accuracy than is possible with a glass reference artifact. Details of the designed features and manufacturing process of the hybrid dimensional artifact are given and a comparison of the designed features to the measured features of the manufactured artifact is presented and discussed. Measurement results from vision and touch probe systems are compared and evaluated to determine the capability of the manufactured artifact to serve as a calibration tool for video-probe systems. An uncertainty analysis for calibration of the artifact using a CMM is presented.

  14. Monolithic Micromachined Quartz Resonator based Infrared Focal Plane Arrays

    Science.gov (United States)

    2012-05-05

    prototypes of integrated micromachined IR detectors consisting of 200 μm diameter QCM resonators, 241 MHz (6.9 μm) thick 5 x 5 resonator arrays from Y-cut...of small QCM devices. • A novel measurement method for the real-time tracking of the resonance frequency based on impedance measurement around the...miniaturize QCM ? • Micromachining Quartz • Evaluation of QCM MicroArrays • Adsorption Experiments – Human Serum Albumin, IgG, and Human Fibrinogen Adsorption

  15. The Cooling and Lubrication Performance of Graphene Platelets in Micro-Machining Environments

    Science.gov (United States)

    Chu, Bryan

    The research presented in this thesis is aimed at investigating the use of graphene platelets (GPL) to address the challenges of excessive tool wear, reduced part quality, and high specific power consumption encountered in micro-machining processes. There are two viable methods of introducing GPL into micro-machining environments, viz., the embedded delivery method, where the platelets are embedded into the part being machined, and the external delivery method, where graphene is carried into the cutting zone by jetting or atomizing a carrier fluid. The study involving the embedded delivery method is focused on the micro-machining performance of hierarchical graphene composites. The results of this study show that the presence of graphene in the epoxy matrix improves the machinability of the composite. In general, the tool wear, cutting forces, surface roughness, and extent of delamination are all seen to be lower for the hierarchical composite when compared to the conventional two-phase glass fiber composite. These improvements are attributed to the fact that graphene platelets improve the thermal conductivity of the matrix, provide lubrication at the tool-chip interface and also improve the interface strength between the glass fibers and the matrix. The benefits of graphene are seen to also carry over to the external delivery method. The platelets provide improved cooling and lubrication performance to both environmentally-benign cutting fluids as well as to semi-synthetic cutting fluids used in micro-machining. The cutting performance is seen to be a function of the geometry (i.e., lateral size and thickness) and extent of oxygen-functionalization of the platelet. Ultrasonically exfoliated platelets (with 2--3 graphene layers and lowest in-solution characteristic lateral length of 120 nm) appear to be the most favorable for micro-machining applications. Even at the lowest concentration of 0.1 wt%, they are capable of providing a 51% reduction in the cutting

  16. Progressing batch hydrolysis process

    Science.gov (United States)

    Wright, John D.

    1986-01-01

    A progressive batch hydrolysis process for producing sugar from a lignocellulosic feedstock, comprising passing a stream of dilute acid serially through a plurality of percolation hydrolysis reactors charged with said feedstock, at a flow rate, temperature and pressure sufficient to substantially convert all the cellulose component of the feedstock to glucose; cooling said dilute acid stream containing glucose, after exiting the last percolation hydrolysis reactor, then feeding said dilute acid stream serially through a plurality of prehydrolysis percolation reactors, charged with said feedstock, at a flow rate, temperature and pressure sufficient to substantially convert all the hemicellulose component of said feedstock to glucose; and cooling the dilute acid stream containing glucose after it exits the last prehydrolysis reactor.

  17. Unveiling the wet chemical etching characteristics of polydimethylsiloxane film for soft micromachining applications

    International Nuclear Information System (INIS)

    Kakati, A; Maji, D; Das, S

    2017-01-01

    Micromachining of a polydimethylsiloxane (PDMS) microstructure by wet chemical etching is explored for microelectromechanical systems (MEMS) and microfluidic applications. A 100 µ m thick PDMS film was patterned with different microstructure designs by wet chemical etching using a N-methyl-2-pyrrolidone (C 16 H 36 FN) and tetra-n-butylammonium fluoride (C 5 H 9 NO) mixture solution with 3:1 volume ratio after lithography for studying etching characteristics. The patterning parameters, such as etch rate, surface roughness, pH of etchant solution with time, were thoroughly investigated. A detailed study of surface morphology with etching time revealed nonlinear behaviour of the PDMS surface roughness and etch rate. A maximum rate of 1.45 µ m min −1 for 10 min etching with surface roughness of 360 nm was achieved. A new approach of wet chemical etching with pH controlled doped etchant was introduced for lower surface roughness of etched microstructures, and a constant etch rate during etching. Variation of the etching rate and surface roughness by pH controlled etching was performed by doping 5–15 gm l −1 of silicic acid (SiO 2xH2 O) into the traditional etchant solution. PDMS etching by silicic acid doped etchant solution showed a reduction in surface roughness from 400 nm to 220 nm for the same 15 µ m etching. This study is beneficial for micromachining of various MEMS and microfluidic structures such as micropillars, microchannels, and other PDMS microstructures. (paper)

  18. Development of a focused ion beam micromachining system

    Energy Technology Data Exchange (ETDEWEB)

    Pellerin, J.G.; Griffis, D.; Russell, P.E.

    1988-12-01

    Focused ion beams are currently being investigated for many submicron fabrication and analytical purposes. An FIB micromachining system consisting of a UHV vacuum system, a liquid metal ion gun, and a control and data acquisition computer has been constructed. This system is being used to develop nanofabrication and nanomachining techniques involving focused ion beams and scanning tunneling microscopes.

  19. Micromachined palladium silver alloy membranes for hydrogen separation

    NARCIS (Netherlands)

    Tong, D.H.; Gielens, F.C.; Berenschot, Johan W.; de Boer, Meint J.; Gardeniers, Johannes G.E.; Jansen, Henricus V.; Nijdam, W.; van Rijn, C.J.M.; Elwenspoek, Michael Curt

    2002-01-01

    This paper presents wafer-scale palladium - silver alloy membranes, fabricated with a sequence of wellknown thin film and silicon micromachining techniques. The membranes have been tested in a gas permeation system to determine the hydrogen permeability and hydrogen selectivity. Typical flow rates

  20. Monitoring of yeast cell concentration using a micromachined impedance sensor

    NARCIS (Netherlands)

    Krommenhoek, E.E.; Gardeniers, Johannes G.E.; Bomer, Johan G.; van den Berg, Albert; Li, X.; Ottens, M.; van der Wielen, L.A.M.; van Dedem, G.W.K.; van Leeuwen, M.; van Gulik, W.M.; Heijnen, J.J.

    2005-01-01

    The paper describes the design, modelling and experimental characterization of a micromachined impedance sensor for on-line monitoring of the viable yeast cell concentration (biomass) in a miniaturized cell assay. Measurements in a Saccharomyces cerevisiae cell culture show that the permittivity of

  1. Optimization of alkaline protease production by batch culture of Bacillus sp. RKY3 through Plackett-Burman and response surface methodological approaches.

    Science.gov (United States)

    Reddy, L V A; Wee, Young-Jung; Yun, Jong-Sun; Ryu, Hwa-Won

    2008-05-01

    The proteolytic enzymes are the most important group of commercially produced enzymes. The production of alkaline protease was optimized using a newly isolated Bacillus sp. RKY3. The fermentation variables were selected in accordance with the Plackett-Burman design and were further optimized via response surface methodological approach. Four significant variables (corn starch, yeast extract, corn steep liquor, and inoculum size) were selected for the optimization studies. The statistical model was constructed via central composite design (CCD) using three screened variables (corn starch, corn steep liquor, and inoculum size). An overall 2.3-fold increase in protease production was achieved in the optimized medium as compared with the unoptimized basal medium. Enzyme activity increased significantly with optimized medium (939 u ml(-1)) when compared with unoptimized medium (417 u ml(-1)).

  2. Biochemical responses of Gammarus pulex to malachite green solutions decolorized by Coriolus versicolor as a biosorbent under batch adsorption conditions optimized with response surface methodology.

    Science.gov (United States)

    Yildirim, Nuran Cikcikoglu; Tanyol, Mehtap; Yildirim, Numan; Serdar, Osman; Tatar, Sule

    2018-03-08

    The current study was aimed to investigate the detoxifying and antioxidant enzyme response of Gammarus pulex exposed to malachite green (MG) after decolorization by Coriolus versicolor. Response surface methodology (RSM) was utilized to optimize the decolorization conditions of MG synthetic solutions by C. versicolor. Glutathione (GSH), malondialdehyde (MDA) levels and glutathione peroxidase (GP X ), catalase (CAT), superoxide dismutase (SOD), glutathione S-transferase (GST), cytochrome P450 1A1 (CYP1A1) activities in G. pulex exposed to undecolorized (A1) and decolorized (A2) MG synthetic solution during 24 and 96 h were tested by using ELISA method. SOD and GP X enzyme activity was increased after decolorization (p > 0.05). CAT enzyme activity was increased in A2 group during 24 h (p > 0.05) but decreased during 96 h (p < 0.05). GSH levels were increased in A2 group during 24 and 96 h (p < 0.05). GST, CYP1A1 enzyme activity and MDA levels were decreased after decolorization during 96 h (p < 0.05). In this study, GSH levels, CAT, GST and CYP1A1 activities in G. pulex approved the capability of C. versicolor in MG decolorization, optimized with RSM. Copyright © 2018 Elsevier Inc. All rights reserved.

  3. PECVD silicon carbide surface micromachining technology and selected MEMS applications

    NARCIS (Netherlands)

    Rajaraman, V.; Pakula, L.S.; Yang, H.; French, P.J.; Sarro, P.M.

    2011-01-01

    Attractive material properties of plasma enhanced chemical vapour deposited (PECVD) silicon carbide (SiC) when combined with CMOS-compatible low thermal budget processing provides an ideal technology platform for developing various microelectromechanical systems (MEMS) devices and merging them with

  4. Control and Optimization of Batch Chemical Processes

    OpenAIRE

    Rohani, Sohrab; Chhabra, Raj; Bonvin, Dominique; François, Grégory

    2017-01-01

    A batch process is characterized by the repetition of time-varying operations of finite duration. Due to the repetition, there are two independent “time” variables, namely, the run time during a batch and the batch index. Accordingly, the control and optimization objectives can be defined for a given batch or over several batches. This chapter describes the various control and optimization strategies available for the operation of batch processes. These include online and run-to-run control o...

  5. Data-driven batch schuduling

    Energy Technology Data Exchange (ETDEWEB)

    Bent, John [Los Alamos National Laboratory; Denehy, Tim [GOOGLE; Arpaci - Dusseau, Remzi [UNIV OF WISCONSIN; Livny, Miron [UNIV OF WISCONSIN; Arpaci - Dusseau, Andrea C [NON LANL

    2009-01-01

    In this paper, we develop data-driven strategies for batch computing schedulers. Current CPU-centric batch schedulers ignore the data needs within workloads and execute them by linking them transparently and directly to their needed data. When scheduled on remote computational resources, this elegant solution of direct data access can incur an order of magnitude performance penalty for data-intensive workloads. Adding data-awareness to batch schedulers allows a careful coordination of data and CPU allocation thereby reducing the cost of remote execution. We offer here new techniques by which batch schedulers can become data-driven. Such systems can use our analytical predictive models to select one of the four data-driven scheduling policies that we have created. Through simulation, we demonstrate the accuracy of our predictive models and show how they can reduce time to completion for some workloads by as much as 80%.

  6. Technology trends in high temperature pressure transducers: The impact of micromachining

    Science.gov (United States)

    Mallon, Joseph R., Jr.

    1992-01-01

    This paper discusses the implications of micromachining technology on the development of high temperature pressure transducers. The introduction puts forth the thesis that micromachining will be the technology of choice for the next generation of extended temperature range pressure transducers. The term micromachining is defined, the technology is discussed and examples are presented. Several technologies for high temperature pressure transducers are discussed, including silicon on insulator, capacitive, optical, and vibrating element. Specific conclusions are presented along with recommendations for development of the technology.

  7. Adaptive Batch Mode Active Learning.

    Science.gov (United States)

    Chakraborty, Shayok; Balasubramanian, Vineeth; Panchanathan, Sethuraman

    2015-08-01

    Active learning techniques have gained popularity to reduce human effort in labeling data instances for inducing a classifier. When faced with large amounts of unlabeled data, such algorithms automatically identify the exemplar and representative instances to be selected for manual annotation. More recently, there have been attempts toward a batch mode form of active learning, where a batch of data points is simultaneously selected from an unlabeled set. Real-world applications require adaptive approaches for batch selection in active learning, depending on the complexity of the data stream in question. However, the existing work in this field has primarily focused on static or heuristic batch size selection. In this paper, we propose two novel optimization-based frameworks for adaptive batch mode active learning (BMAL), where the batch size as well as the selection criteria are combined in a single formulation. We exploit gradient-descent-based optimization strategies as well as properties of submodular functions to derive the adaptive BMAL algorithms. The solution procedures have the same computational complexity as existing state-of-the-art static BMAL techniques. Our empirical results on the widely used VidTIMIT and the mobile biometric (MOBIO) data sets portray the efficacy of the proposed frameworks and also certify the potential of these approaches in being used for real-world biometric recognition applications.

  8. Capacitive Micromachined Ultrasonic Transducers (CMUTs for Underwater Imaging Applications

    Directory of Open Access Journals (Sweden)

    Jinlong Song

    2015-09-01

    Full Text Available A capacitive micromachined ultrasonic transducer structure for use in underwater imaging is designed, fabricated and tested in this paper. In this structure, a silicon dioxide insulation layer is inserted between the top electrodes and the vibration membrane to prevent ohmic contact. The capacitance-voltage (C-V characteristic curve shows that the transducer offers suitable levels of hysteresis and repeatability performance. The −6 dB center frequency is 540 kHz and the transducer has a bandwidth of 840 kHz for a relative bandwidth of 155%. Underwater pressure of 143.43 Pa is achieved 1 m away from the capacitive micromachined ultrasonic transducer under 20  excitation. Two-dimensional underwater ultrasonic imaging, which is able to prove that a rectangular object is present underwater, is achieved. The results presented here indicate that our work will be highly beneficial for the establishment of an underwater ultrasonic imaging system.

  9. Artificial intelligence: Collective behaviors of synthetic micromachines

    Science.gov (United States)

    Duan, Wentao

    Synthetic nano- and micromotors function through the conversion of chemical free energy or forms of energy into mechanical motion. Ever since the first reports, such motors have been the subject of growing interest. In addition to motility in response to gradients, these motors interact with each other, resulting in emergent collective behavior like schooling, exclusion, and predator-prey. However, most of these systems only exhibit a single type of collective behavior in response to a certain stimuli. The research projects in the disseratation aim at designing synthetic micromotors that can exhibit transition between various collective behaviors in response to different stimuli, as well as quantitative understanding on the pairwise interaction and propulsion mechanism of such motors. Chapter 1 offers an overview on development of synthetic micromachines. Interactions and collective behaviors of micromotors are also summarized and included. Chapter 2 presents a silver orthophosphate microparticle system that exhibits collective behaviors. Transition between two collective patterns, clustering and dispersion, can be triggered by shift in chemical equilibrium upon the addition or removal of ammonia, in response to UV light, or under two orthogonal stimuli (UV and acoustic field) and powering mechanisms. The transitions can be explained by the self-diffusiophoresis mechanism resulting from either ionic or neutral solute gradients. Potential applications of the reported system in logic gates, microscale pumping, and hierarchical assembly have been demonstrated. Chapter 3 introduces a self-powered oscillatory micromotor system in which active colloids form clusters whose size changes periodically. The system consists of an aqueous suspension of silver orthophosphate particles under UV radiation, in the presence of a mixture of glucose and hydrogen peroxide. The colloid particles first attract with each other to form clusters. After a lag time of around 5min, chemical

  10. High-speed Laser Micromachining with Copper Bromide Laser

    OpenAIRE

    Balchev, Ivaylo I.; Minkovski, Nikolai I.; Kostadinov, Ivan K.; Sabotinov, Nikola V.

    2006-01-01

    The application of the copper bromide (CuBr) laser as an attractive tool in the micro-machining of different materials has been demonstrated. High-quality drilling by trepanning and precision cutting was established on several materials with a negligible heat-affected zone (HAZ). That good performance was a result of the combination of high power visible radiation, short pulses, and close to the diffraction-limited laser beam quality with high-speed galvo scanner beam steering.

  11. High lane density slab-gel electrophoresis using micromachined instrumentation.

    Science.gov (United States)

    Papautsky, I; Mohanty, S; Weiss, R; Frazier, A B

    2001-10-01

    In this paper, micromachined pipette arrays (MPAs) and microcombs were studied as a means of enabling high lane density gel electrophoresis. The MPA provide a miniaturized format to interface sub-microliter volumes of samples between macroscale sample preparation formats and microscale biochemical analysis systems. The microcombs provide a means of creating sample loading wells in the gel material on the same center-to-center spacing as the MPAs. Together, the two micromachined instruments provide an alternative to current combs and pipetting technologies used for creating sample loading wells and sample delivery in gel electrophoresis systems. Using three designs for the microcomb-MPA pair, center-to-center spacings of 1.0 mm, 500 microm, and 250 microm are studied. The results demonstrate an approximate 10-fold increase in lane density and a 10-fold reduction in sample size from 5 microL to 500 pL. As a result, the number of theoretical plates has increased 2.5-fold, while system resolution has increased 1.5-fold over the conventional agarose gel systems. An examination of changes in resolution across the width of individual separation lanes in both systems revealed dependence in the case of the conventional gels and no dependence for the gels loaded with the micromachined instrumentation.

  12. Fabrication of capacitive micromachined ultrasonic transducers based on adhesive wafer bonding technique

    International Nuclear Information System (INIS)

    Li, Zhenhao; Wong, Lawrence L P; Chen, Albert I H; Na, Shuai; Yeow, John T W; Sun, Jame

    2016-01-01

    This paper reports the fabrication process of wafer bonded capacitive micromachined ultrasonic transducers (CMUTs) using photosensitive benzocyclobutene as a polymer adhesive. Compared with direct bonding and anodic bonding, polymer adhesive bonding provides good tolerance to wafer surface defects and contamination. In addition, the low process temperature of 250 °C is compatible with standard CMOS processes. Single-element CMUTs consisting of cells with a diameter of 46 µ m and a cavity depth of 323 nm were fabricated. In-air and immersion acoustic characterizations were performed on the fabricated CMUTs, demonstrating their capability for transmitting and receiving ultrasound signals. An in-air resonance frequency of 5.47 MHz was measured by a vibrometer under a bias voltage of 300 V. (paper)

  13. Non-contact thermoacoustic detection of embedded targets using airborne-capacitive micromachined ultrasonic transducers

    Science.gov (United States)

    Nan, Hao; Boyle, Kevin C.; Apte, Nikhil; Aliroteh, Miaad S.; Bhuyan, Anshuman; Nikoozadeh, Amin; Khuri-Yakub, Butrus T.; Arbabian, Amin

    2015-02-01

    A radio frequency (RF)/ultrasound hybrid imaging system using airborne capacitive micromachined ultrasonic transducers (CMUTs) is proposed for the remote detection of embedded objects in highly dispersive media (e.g., water, soil, and tissue). RF excitation provides permittivity contrast, and ultra-sensitive airborne-ultrasound detection measures thermoacoustic-generated acoustic waves that initiate at the boundaries of the embedded target, go through the medium-air interface, and finally reach the transducer. Vented wideband CMUTs interface to 0.18 μm CMOS low-noise amplifiers to provide displacement detection sensitivity of 1.3 pm at the transducer surface. The carefully designed vented CMUT structure provides a fractional bandwidth of 3.5% utilizing the squeeze-film damping of the air in the cavity.

  14. High frequency ultrasonic imaging using thermal mechanical noise recorded on capacitive micromachined transducer arrays

    Science.gov (United States)

    Lani, Shane; Satir, Sarp; Gurun, Gokce; Sabra, Karim G.; Levent Degertekin, F.

    2011-11-01

    The cross-correlation of diffuse thermal-mechanical noise recorded by two sensors yields an estimate of the ultrasonic waves propagating between them. We used this approach at high frequencies (1-30 MHz) on a capacitive micromachined ultrasonic transducer (CMUT) ring array (d = 725 μm), monolithically integrated with low noise complementary metal oxide semiconductor electronics. The thermal-mechanical noise cross-correlations between the CMUT array elements in immersion reveal both evanescent surface waves (below 10 MHz) and waves propagating primarily in the fluid (above 10 MHz). These propagating waves may allow passive imaging of scatterers closer to the array as compared to conventional pulse-echo systems, providing potentially higher resolution.

  15. A Flexible Ultrasound Transducer Array with Micro-Machined Bulk PZT

    Directory of Open Access Journals (Sweden)

    Zhe Wang

    2015-01-01

    Full Text Available This paper proposes a novel flexible piezoelectric micro-machined ultrasound transducer, which is based on PZT and a polyimide substrate. The transducer is made on the polyimide substrate and packaged with medical polydimethylsiloxane. Instead of etching the PZT ceramic, this paper proposes a method of putting diced PZT blocks into holes on the polyimide which are pre-etched. The device works in d31 mode and the electromechanical coupling factor is 22.25%. Its flexibility, good conformal contacting with skin surfaces and proper resonant frequency make the device suitable for heart imaging. The flexible packaging ultrasound transducer also has a good waterproof performance after hundreds of ultrasonic electric tests in water. It is a promising ultrasound transducer and will be an effective supplementary ultrasound imaging method in the practical applications.

  16. Lead-Free Piezoelectric Diaphragm Biosensors Based on Micro-Machining Technology and Chemical Solution Deposition.

    Science.gov (United States)

    Li, Xiaomeng; Wu, Xiaoqing; Shi, Peng; Ye, Zuo-Guang

    2016-01-12

    In this paper, we present a new approach to the fabrication of integrated silicon-based piezoelectric diaphragm-type biosensors by using sodium potassium niobate-silver niobate (0.82KNN-0.18AN) composite lead-free thin film as the piezoelectric layer. The piezoelectric diaphragms were designed and fabricated by micro-machining technology and chemical solution deposition. The fabricated device was very sensitive to the mass changes caused by various targets attached on the surface of diaphragm. The measured mass sensitivity value was about 931 Hz/μg. Its good performance shows that the piezoelectric diaphragm biosensor can be used as a cost-effective platform for nucleic acid testing.

  17. Lead-Free Piezoelectric Diaphragm Biosensors Based on Micro-Machining Technology and Chemical Solution Deposition

    Directory of Open Access Journals (Sweden)

    Xiaomeng Li

    2016-01-01

    Full Text Available In this paper, we present a new approach to the fabrication of integrated silicon-based piezoelectric diaphragm-type biosensors by using sodium potassium niobate-silver niobate (0.82KNN-0.18AN composite lead-free thin film as the piezoelectric layer. The piezoelectric diaphragms were designed and fabricated by micro-machining technology and chemical solution deposition. The fabricated device was very sensitive to the mass changes caused by various targets attached on the surface of diaphragm. The measured mass sensitivity value was about 931 Hz/μg. Its good performance shows that the piezoelectric diaphragm biosensor can be used as a cost-effective platform for nucleic acid testing.

  18. Improving the Design of Capacitive Micromachined Ultrasonic Transducers Aided with Sensitivity Analysis

    Directory of Open Access Journals (Sweden)

    A Martowicz

    2016-09-01

    Full Text Available The paper presents the results of analysis performed to search for feasible design improvements for capacitive micromachined ultrasonic transducer. Carried out search has been aided with the sensitivity analysis and the application of Response Surface Method. The multiphysics approach has been taken into account in elaborated finite element model of one cell of described transducer in order to include significant physical phenomena present in modelled microdevice. The set of twelve input uncertain and design parameters consists of geometric, material and control properties. The amplitude of dynamic membrane deformation of the transducer has been chosen as studied parameter. The objective of performed study has been defined as the task of finding robust design configurations of the transducer, i.e. characterizing maximal value of deformation amplitude with its minimal variation.

  19. Freeform micromachining of an infrared Alvarez lens

    Science.gov (United States)

    Smilie, Paul J.; Dutterer, Brian S.; Lineberger, Jennifer L.; Davies, Matthew A.; Suleski, Thomas J.

    2011-02-01

    In 1967, Luis Alvarez introduced a novel concept for a focusing lens whereby two transmitting elements with cubic polynomial surfaces yield a composite lens of variable focal length with small lateral shifts. Computer simulations have demonstrated the behavior of these devices, but fabricating the refractive cubic surfaces of the types needed with adequate precision and depth modulation has proven to be challenging using standard methods, and, to the authors' knowledge, Alvarez lens elements have not been previously machined in infrared materials. Recent developments in freeform diamond machining capability have enabled the fabrication of such devices. In this paper, we discuss the fabrication of freeform refractive Alvarez elements in germanium using diamond micro-milling on a five-axis Moore Nanotech® 350FG Freeform Generator. Machining approaches are discussed, and measurements of surface figure and finish are presented. Initial experimental tests of optical performance are also discussed.

  20. Micromachining of inertial confinement fusion targets

    International Nuclear Information System (INIS)

    Gobby, P.L.; Salzer, L.J.; Day, R.D.

    1996-01-01

    Many experiments conducted on today's largest inertial confinement fusion drive lasers require target components with sub-millimeter dimensions, precisions of a micron or less and surface finishes measured in nanometers. For metal and plastic, techniques using direct machining with diamond tools have been developed that yield the desired parts. New techniques that will be discussed include the quick-flip locator, a magnetically held kinematic mount that has allowed the direct machining of millimeter-sized beryllium hemishells whose inside and outside surface are concentric to within 0.25 micron, and an electronic version of a tracer lathe which has produced precise azimuthal variations of less than a micron

  1. BatchJS: Implementing Batches in JavaScript

    NARCIS (Netherlands)

    D. Kasemier

    2014-01-01

    htmlabstractNone of our popular programming languages know how to handle distribution well. Yet our programs interact more and more with each other and our data resorts in databases and web services. Batches are a new addition to languages that can finally bring native support for distribution to

  2. Analysis of Adiabatic Batch Reactor

    Directory of Open Access Journals (Sweden)

    Erald Gjonaj

    2016-05-01

    Full Text Available A mixture of acetic anhydride is reacted with excess water in an adiabatic batch reactor to form an exothermic reaction. The concentration of acetic anhydride and the temperature inside the adiabatic batch reactor are calculated with an initial temperature of 20°C, an initial temperature of 30°C, and with a cooling jacket maintaining the temperature at a constant of 20°C. The graphs of the three different scenarios show that the highest temperatures will cause the reaction to occur faster.

  3. NDA BATCH 2002-02

    Energy Technology Data Exchange (ETDEWEB)

    Lawrence Livermore National Laboratory

    2009-12-09

    QC sample results (daily background checks, 20-gram and 100-gram SGS drum checks) were within acceptable criteria established by WIPP's Quality Assurance Objectives for TRU Waste Characterization. Replicate runs were performed on 5 drums with IDs LL85101099TRU, LL85801147TRU, LL85801109TRU, LL85300999TRU and LL85500979TRU. All replicate measurement results are identical at the 95% confidence level as established by WIPP criteria. Note that the batch covered 5 weeks of SGS measurements from 23-Jan-2002 through 22-Feb-2002. Data packet for SGS Batch 2002-02 generated using gamma spectroscopy with the Pu Facility SGS unit is technically reasonable. All QC samples are in compliance with established control limits. The batch data packet has been reviewed for correctness, completeness, consistency and compliance with WIPP's Quality Assurance Objectives and determined to be acceptable. An Expert Review was performed on the data packet between 28-Feb-02 and 09-Jul-02 to check for potential U-235, Np-237 and Am-241 interferences and address drum cases where specific scan segments showed Se gamma ray transmissions for the 136-keV gamma to be below 0.1 %. Two drums in the batch showed Pu-238 at a relative mass ratio more than 2% of all the Pu isotopes.

  4. Design, simulation and testing of capacitive micromachined ultrasound transducer-based phospholipidic biosensor elements

    International Nuclear Information System (INIS)

    Sapeliauskas, E; Vanagas, G; Barauskas, D; Mikolajunas, M; Pakenas, E; Pelenis, D; Sergalis, G; Jukna, T; Virzonis, D

    2015-01-01

    In this study we present theoretical proof of the principle of using interdigital capacitive micromachined ultrasound transducers (CMUT IDTs) for the detection of phospholipid membrane elasticity. Proof of principle was needed to find out whether the new type of microelectromechanical sensors of the toxins incorporated with the lipid membranes was feasible. CMUT IDTs for 10 MHz operation in water, with 146 µm spaced double fingers were designed and fabricated using the surface micromachining technique. Fabricated CMUTs were tested for their resonance in air and for Scholte-type wave transmission in deionized water and isopropanol solutions containing 0%, 10% and 20% water. The amplitude and phase velocity of the excited and received Scholte waves were measured in a 200 µm height microchannel, capped with a thick layer of soft polymer, which suppressed the production of non-informative guided waves. It was determined that the average sensitivity of Scholte wave phase velocity within the given range of solution concentrations is 2.9 m s −1 per one percent. Experimental data were also used to verify the adequacy of the finite element model, which was found to be suitable for reliable prediction of the phospholipid membrane elasticity impact on the Scholte wave phase velocity or the resonance frequency in the present IDT structure. It was determined that for the analyzed conditions (the elasticity of simulated phospholipid membrane changed from 1 to 5 GPa) the sensitivity of the measurement channel is expected to be no worse than 2 kHz GPa −1 in terms of the Scholte wave and CMUT IDT resonance frequency. This leads to a positive conclusion on the feasibility of the new sensor type. (paper)

  5. Design, simulation and testing of capacitive micromachined ultrasound transducer-based phospholipidic biosensor elements

    Science.gov (United States)

    Sapeliauskas, E.; Vanagas, G.; Barauskas, D.; Mikolajunas, M.; Pakenas, E.; Pelenis, D.; Sergalis, G.; Jukna, T.; Virzonis, D.

    2015-07-01

    In this study we present theoretical proof of the principle of using interdigital capacitive micromachined ultrasound transducers (CMUT IDTs) for the detection of phospholipid membrane elasticity. Proof of principle was needed to find out whether the new type of microelectromechanical sensors of the toxins incorporated with the lipid membranes was feasible. CMUT IDTs for 10 MHz operation in water, with 146 µm spaced double fingers were designed and fabricated using the surface micromachining technique. Fabricated CMUTs were tested for their resonance in air and for Scholte-type wave transmission in deionized water and isopropanol solutions containing 0%, 10% and 20% water. The amplitude and phase velocity of the excited and received Scholte waves were measured in a 200 µm height microchannel, capped with a thick layer of soft polymer, which suppressed the production of non-informative guided waves. It was determined that the average sensitivity of Scholte wave phase velocity within the given range of solution concentrations is 2.9 m s-1 per one percent. Experimental data were also used to verify the adequacy of the finite element model, which was found to be suitable for reliable prediction of the phospholipid membrane elasticity impact on the Scholte wave phase velocity or the resonance frequency in the present IDT structure. It was determined that for the analyzed conditions (the elasticity of simulated phospholipid membrane changed from 1 to 5 GPa) the sensitivity of the measurement channel is expected to be no worse than 2 kHz GPa-1 in terms of the Scholte wave and CMUT IDT resonance frequency. This leads to a positive conclusion on the feasibility of the new sensor type.

  6. Proton beam micromachining on PMMA, Foturan and CR-39 materials

    CERN Document Server

    Rajta, I; Kiss, A Z; Gomez-Morilla, I; Abraham, M H

    2003-01-01

    Proton Beam Micromachining was demonstrated at the Institute of Nuclear Research of the Hungarian Academy of Sciences using three different types of resists: PMMA, Foturan and CR-39 type Solid State Nuclear Track Detector material. Irradiations have been performed on the nuclear microprobe facility at ATOMKI. The beam scanning was done using a National Instruments (NI) card (model 6711), and the new C++ version of the program IonScan, developed specifically for PBM applications called IonScan 2.0. (R.P.)

  7. Capacitive micromachined ultrasonic transducer arrays as tunable acoustic metamaterials

    International Nuclear Information System (INIS)

    Lani, Shane W.; Sabra, Karim G.; Wasequr Rashid, M.; Hasler, Jennifer; Levent Degertekin, F.

    2014-01-01

    Capacitive Micromachined Ultrasonic Transducers (CMUTs) operating in immersion support dispersive evanescent waves due to the subwavelength periodic structure of electrostatically actuated membranes in the array. Evanescent wave characteristics also depend on the membrane resonance which is modified by the externally applied bias voltage, offering a mechanism to tune the CMUT array as an acoustic metamaterial. The dispersion and tunability characteristics are examined using a computationally efficient, mutual radiation impedance based approach to model a finite-size array and realistic parameters of variation. The simulations are verified, and tunability is demonstrated by experiments on a linear CMUT array operating in 2-12 MHz range

  8. Capacitive micromachined ultrasonic transducer arrays as tunable acoustic metamaterials

    Energy Technology Data Exchange (ETDEWEB)

    Lani, Shane W., E-mail: shane.w.lani@gmail.com, E-mail: karim.sabra@me.gatech.edu, E-mail: levent.degertekin@me.gatech.edu; Sabra, Karim G. [George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, 801Ferst Drive, Georgia 30332-0405 (United States); Wasequr Rashid, M.; Hasler, Jennifer [School of Electrical and Computer Engineering, Georgia Institute of Technology, Van Leer Electrical Engineering Building, 777 Atlantic Drive NW, Atlanta, Georgia 30332-0250 (United States); Levent Degertekin, F. [George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, 801Ferst Drive, Georgia 30332-0405 (United States); School of Electrical and Computer Engineering, Georgia Institute of Technology, Van Leer Electrical Engineering Building, 777 Atlantic Drive NW, Atlanta, Georgia 30332-0250 (United States)

    2014-02-03

    Capacitive Micromachined Ultrasonic Transducers (CMUTs) operating in immersion support dispersive evanescent waves due to the subwavelength periodic structure of electrostatically actuated membranes in the array. Evanescent wave characteristics also depend on the membrane resonance which is modified by the externally applied bias voltage, offering a mechanism to tune the CMUT array as an acoustic metamaterial. The dispersion and tunability characteristics are examined using a computationally efficient, mutual radiation impedance based approach to model a finite-size array and realistic parameters of variation. The simulations are verified, and tunability is demonstrated by experiments on a linear CMUT array operating in 2-12 MHz range.

  9. Development of capacitive Micromachined Ultrasonic Transducer (III) - Performance Test

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ki Bok; Ahn, Bong Young; Park, Hae Won; Kim, Young Joo; Lee, Seung Seok [Korea Research Institute of Standards and Science, Daejeon (Korea, Republic of)

    2004-12-15

    In this study, the capacitive micromachined ultrasonic transducer(cMUT) was developed based on the previous research results. The cross sectional image of the developed cMUT was characterized. To measure the membrane displacement of the cMUT, the Michelson phase modulation fiber interferometer was constructed. The measured membrane displacement was in good agreement with the result of the finite element analysis. To estimate the ultrasonic wave generated by the cMUT, an ultrasonic system including a pulser, receiver and charge amplifier was used. The cMUT developed in this study shows a good performance and hence will be widely used in the non-contact ultrasonic applications

  10. Capacitive micromachined ultrasonic transducer arrays as tunable acoustic metamaterials

    Science.gov (United States)

    Lani, Shane W.; Wasequr Rashid, M.; Hasler, Jennifer; Sabra, Karim G.; Levent Degertekin, F.

    2014-02-01

    Capacitive Micromachined Ultrasonic Transducers (CMUTs) operating in immersion support dispersive evanescent waves due to the subwavelength periodic structure of electrostatically actuated membranes in the array. Evanescent wave characteristics also depend on the membrane resonance which is modified by the externally applied bias voltage, offering a mechanism to tune the CMUT array as an acoustic metamaterial. The dispersion and tunability characteristics are examined using a computationally efficient, mutual radiation impedance based approach to model a finite-size array and realistic parameters of variation. The simulations are verified, and tunability is demonstrated by experiments on a linear CMUT array operating in 2-12 MHz range.

  11. Development of capacitive Micromachined Ultrasonic Transducer (III) - Performance Test

    International Nuclear Information System (INIS)

    Kim, Ki Bok; Ahn, Bong Young; Park, Hae Won; Kim, Young Joo; Lee, Seung Seok

    2004-01-01

    In this study, the capacitive micromachined ultrasonic transducer(cMUT) was developed based on the previous research results. The cross sectional image of the developed cMUT was characterized. To measure the membrane displacement of the cMUT, the Michelson phase modulation fiber interferometer was constructed. The measured membrane displacement was in good agreement with the result of the finite element analysis. To estimate the ultrasonic wave generated by the cMUT, an ultrasonic system including a pulser, receiver and charge amplifier was used. The cMUT developed in this study shows a good performance and hence will be widely used in the non-contact ultrasonic applications

  12. Photothermal self-excitation of the micromachined resonators

    Science.gov (United States)

    Churenkov, Alexander V.; Kozel, Stanislav M.; Listvin, Vladimir N.

    1990-07-01

    Recently interest has grown to the physical quantities fibre-optic sensors in which a micromachined resonator acts as a sensitive element. This resonator can change the resonant frequency when acted upon by an outside force. Energy supply necessary for the resonator excitation and transfer of information about the outer action are accomplished by optical fibres, that can be present in the zone of a higher aggressiveness, strong electromagnetic interferences atc. The frequency output of such sensors is easily processed by digital systems and is insensitive to signal level.

  13. Micromachined silicon grisms for infrared optics.

    Science.gov (United States)

    Mar, Douglas J; Marsh, Jasmina P; Deen, Casey P; Ling, Hao; Choo, Hosung; Jaffe, Daniel T

    2009-02-20

    We demonstrate the successful fabrication of large format (approximately 50 mm × 50 mm) gratings in monolithic silicon for use as high-efficiency grisms at infrared wavelengths. The substrates for the grisms were thick (8-16 mm) disks of precisely oriented single-crystal silicon (refractive index, n ~ 3.42). We used microlithography and chemical wet etching techniques to produce the diffraction gratings on one side of these substrates. These techniques permitted the manufacture of coarse grooves (as few as 7 grooves/mm) with precise control of the blaze angle and groove profile and resulted in excellent groove surface quality. Profilometric measurements of the groove structure of the gratings confirm that the physical dimensions of the final devices closely match their design values. Optical performance of these devices exceeds the specifications required for diffraction-limited performance (RMS wave surface error silicon transmits well, the blaze control and high index permit high-resolution, high-order dispersion in a compact space. The first application of these grisms is to provide FORCAST, a mid-infrared camera on NASA's airborne observatory, with a moderate resolution (R=100-1000) spectroscopic capability.

  14. Analysis of Tank 38H (HTF-38-15-119, 127) Surface, Subsurface and Tank 43H (HTF-43-15-116, 117 and 118) Surface, Feed Pump Suction and Jet Suction Subsurface Supernatant Samples in Support of Enrichment, Corrosion Control and Salt Batch Planning Programs

    Energy Technology Data Exchange (ETDEWEB)

    Oji, L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2015-12-17

    Compositional feed limits have been established to ensure that a nuclear criticality event for the 2H and 3H Evaporators is not possible. The Enrichment Control Program (ECP) requires feed sampling to determine the equivalent enriched uranium content prior to transfer of waste other than recycle transfers (requires sampling to determine the equivalent enriched uranium at two locations in Tanks 38H and 43H every 26 weeks) The Corrosion Control Program (CCP) establishes concentration and temperature limits for key constituents and periodic sampling and analysis to confirm that waste supernate is within these limits. This report provides the results of analyses on Tanks 38H and 43H surface and subsurface supernatant liquid samples in support of the ECP, the CCP, and the Salt Batch 10 Planning Program.

  15. NGBAuth - Next Generation Batch Authentication for long running batch jobs.

    CERN Document Server

    Juto, Zakarias

    2015-01-01

    This document describes the prototyping of a new solution for the CERN batch authentication of long running jobs. While the job submission requires valid user credentials, these have to be renewed due to long queuing and execution times. Described within is a new system which will guarantee a similar level of security as the old LSFAuth while simplifying the implementation and the overall architecture. The new system is being built on solid, streamlined and tested components (notably OpenSSL) and a priority has been to make it more generic in order to facilitate the evolution of the current system such as for the expected migration from LSF to Condor as backend batch system.

  16. Fabrication and Characterization of Capacitive Micromachined Ultrasonic Transducers with Low-Temperature Wafer Direct Bonding

    Directory of Open Access Journals (Sweden)

    Xiaoqing Wang

    2016-12-01

    Full Text Available This paper presents a fabrication method of capacitive micromachined ultrasonic transducers (CMUTs by wafer direct bonding, which utilizes both the wet chemical and O2plasma activation processes to decrease the bonding temperature to 400 °C. Two key surface properties, the contact angle and surface roughness, are studied in relation to the activation processes, respectively. By optimizing the surface activation parameters, a surface roughness of 0.274 nm and a contact angle of 0° are achieved. The infrared images and static deflection of devices are assessed to prove the good bonding effect. CMUTs having silicon membranes with a radius of 60 μm and a thickness of 2 μm are fabricated. Device properties have been characterized by electrical and acoustic measurements to verify their functionality and thus to validate this low-temperature process. A resonant frequency of 2.06 MHz is obtained by the frequency response measurements. The electrical insertion loss and acoustic signal have been evaluated. This study demonstrates that the CMUT devices can be fabricated by low-temperature wafer direct bonding, which makes it possible to integrate them directly on top of integrated circuit (IC substrates.

  17. Capacitive micromachined ultrasonic resonator for ultra sensitive trace gas detection

    Science.gov (United States)

    Ge, Li-Feng

    2013-01-01

    The ultra-sensitive trace gas detection has become increasingly important due to the demand for environment and sci-tech progress. In recent years a capacitive micromachined ultrasonic transducer (CMUT) with circular diaphragms used for imaging has been successfully used to detect chemical gases, and shows promising results. However, its behavior is the same as that of CMUTs for ranging, imaging and therapy applications, where the acoustic radiation with a certain power, produced by the vibration of circular diaphragms operating at the first bending mode, is required but is undesirable for gas sensing since it disturbs inevitably the environment to be measured. This paper, therefore, presents to optimize its behavior after an ideal capacitive micromachined ultrasonic resonator (CMUR) and then to utilize second-order and high-order bending modes of the circular diaphragm to minimize its acoustic radiation and obtain higher resonance frequency also. Since the resonance frequencies of high-order modes much higher than the fundamental frequency, an ultra-high operating frequency of GHz can be reached so that raising greatly the sensitivity of the CMUR and being able to realize the ultra-sensitive trace gas detections.

  18. Parametric studies on the nanosecond laser micromachining of the materials

    Science.gov (United States)

    Tański, M.; Mizeraczyk, J.

    2016-12-01

    In this paper the results of an experimental studies on nanosecond laser micromachining of selected materials are presented. Tested materials were thin plates made of aluminium, silicon, stainless steel (AISI 304) and copper. Micromachining of those materials was carried out using a solid state laser with second harmonic generation λ = 532 nm and a pulse width of τ = 45 ns. The effect of laser drilling using single laser pulse and a burst of laser pulses, as well as laser cutting was studied. The influence of laser fluence on the diameter and morphology of a post ablation holes drilled with a single laser pulse was investigated. The ablation fluence threshold (Fth) of tested materials was experimentally determined. Also the drilling rate (average depth per single laser pulse) of holes drilled with a burst of laser pulses was determined for all tested materials. The studies of laser cutting process revealed that a groove depth increases with increasing average laser power and decreasing cutting speed. It was also found that depth of the laser cut grooves is a linear function of number of repetition of a cut. The quantitative influence of those parameters on the groove depth was investigated.

  19. Hybrid micromachining using a nanosecond pulsed laser and micro EDM

    International Nuclear Information System (INIS)

    Kim, Sanha; Chung, Do Kwan; Shin, Hong Shik; Chu, Chong Nam; Kim, Bo Hyun

    2010-01-01

    Micro electrical discharge machining (micro EDM) is a well-known precise machining process that achieves micro structures of excellent quality for any conductive material. However, the slow machining speed and high tool wear are main drawbacks of this process. Though the use of deionized water instead of kerosene as a dielectric fluid can reduce the tool wear and increase the machine speed, the material removal rate (MRR) is still low. In contrast, laser ablation using a nanosecond pulsed laser is a fast and non-wear machining process but achieves micro figures of rather low quality. Therefore, the integration of these two processes can overcome the respective disadvantages. This paper reports a hybrid process of a nanosecond pulsed laser and micro EDM for micromachining. A novel hybrid micromachining system that combines the two discrete machining processes is introduced. Then, the feasibility and characteristics of the hybrid machining process are investigated compared to conventional EDM and laser ablation. It is verified experimentally that the machining time can be effectively reduced in both EDM drilling and milling by rapid laser pre-machining prior to micro EDM. Finally, some examples of complicated 3D micro structures fabricated by the hybrid process are shown

  20. Eye Vision Testing System and Eyewear Using Micromachines

    Directory of Open Access Journals (Sweden)

    Nabeel A. Riza

    2015-11-01

    Full Text Available Proposed is a novel eye vision testing system based on micromachines that uses micro-optic, micromechanic, and microelectronic technologies. The micromachines include a programmable micro-optic lens and aperture control devices, pico-projectors, Radio Frequency (RF, optical wireless communication and control links, and energy harvesting and storage devices with remote wireless energy transfer capabilities. The portable lightweight system can measure eye refractive powers, optimize light conditions for the eye under testing, conduct color-blindness tests, and implement eye strain relief and eye muscle exercises via time sequenced imaging. A basic eye vision test system is built in the laboratory for near-sighted (myopic vision spherical lens refractive error correction. Refractive error corrections from zero up to −5.0 Diopters and −2.0 Diopters are experimentally demonstrated using the Electronic-Lens (E-Lens and aperture control methods, respectively. The proposed portable eye vision test system is suited for children’s eye tests and developing world eye centers where technical expertise may be limited. Design of a novel low-cost human vision corrective eyewear is also presented based on the proposed aperture control concept. Given its simplistic and economical design, significant impact can be created for humans with vision problems in the under-developed world.

  1. Long-term outdoor reliability assessment of a wireless unit for air-quality monitoring based on nanostructured films integrated on micromachined platforms.

    Science.gov (United States)

    Leccardi, Matteo; Decarli, Massimiliano; Lorenzelli, Leandro; Milani, Paolo; Mettala, Petteri; Orava, Risto; Barborini, Emanuele

    2012-01-01

    We have fabricated and tested in long-term field operating conditions a wireless unit for outdoor air quality monitoring. The unit is equipped with two multiparametric sensors, one miniaturized thermo-hygrometer, front-end analogical and digital electronics, and an IEEE 802.15.4 based module for wireless data transmission. Micromachined platforms were functionalized with nanoporous metal-oxides to obtain multiparametric sensors, hosting gas-sensitive, anemometric and temperature transducers. Nanoporous metal-oxide layer was directly deposited on gas sensing regions of micromachined platform batches by hard-mask patterned supersonic cluster beam deposition. An outdoor, roadside experiment was arranged in downtown Milan (Italy), where one wireless sensing unit was continuously operated side by side with standard gas chromatographic instrumentation for air quality measurements. By means of a router PC, data from sensing unit and other instrumentation were collected, merged, and sent to a remote data storage server, through an UMTS device. The whole-system robustness as well as sensor dataset characteristics were continuously characterized over a run-time period of 18 months.

  2. Micromachined chemical sensor with integrated microelectronics

    International Nuclear Information System (INIS)

    Smith, J.; Sniegowski, J.; Koehler, D.; Ricco, T.; Martin, S.; McWhorter, P.

    1992-01-01

    With today's continued emphasis on environmental safety and health issues, a resurgence of interest has developed in the area of chemical sensors. These sensors would typically be used to monitor contamination hazards such as underground storage tanks or to assess previous contamination at waste disposal sites. Human exposure to chemical hazards can also be monitored. Additionally, these sensors can be used as part of a manufacturing process control loop. One type of sensor suitable for gas phase monitoring of chemicals is the quartz resonator or quartz crystal microbalance (QCM) sensor. In this type of sensor, a thickness shear mode (TSM) quartz resonator is coated with a film that interacts with the chemical species of interest. Changes in the mass and elasticity of this film are reflected as changes in the resonant properties of the device. Therefore, the presence of the species of interest can be detected by monitoring the frequency of an oscillator based on the resonance of the quartz. These QCM sensors compete with surface acoustic wave (SAW) devices as a means for monitoring gas phase species. SAW devices are typically more sensitive to small amounts of a species, but the instrumentation associated with a SAW device is an order of magnitude more expensive than the instrumentation associated with a TSM wave resonator since the SAW devices operate in the 100's of MHz frequency regime while quartz resonators operate in the 5--25 MHz regime. We are working to improve the sensitivity of the QCM sensor by increasing the frequency of the device to 25 MHz (compared to the typical 5 MHz crystal) and by increasing the frequency stability of the system to an ultimate goal of 0.1 Hz. The 25 MHz QCM has already been achieved and once the stability goal is achieved, the QCM will have the same sensitivity as a SAW device

  3. PROOF on a Batch System

    International Nuclear Information System (INIS)

    Behrenhoff, W; Ehrenfeld, W; Samson, J; Stadie, H

    2011-01-01

    The 'parallel ROOT facility' (PROOF) from the ROOT framework provides a mechanism to distribute the load of interactive and non-interactive ROOT sessions on a set of worker nodes optimising the overall execution time. While PROOF is designed to work on a dedicated PROOF cluster, the benefits of PROOF can also be used on top of another batch scheduling system with the help of temporary per user PROOF clusters. We will present a lightweight tool which starts a temporary PROOF cluster on a SGE based batch cluster or, via a plugin mechanism, e.g. on a set of bare desktops via ssh. Further, we will present the result of benchmarks which compare the data throughput for different data storage back ends available at the German National Analysis Facility (NAF) at DESY.

  4. Demonstration of robust micromachined jet technology and its application to realistic flow control problems

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Sung Pil [Inha University, Incheon (Korea, Republic of)

    2006-04-15

    This paper describes the demonstration of successful fabrication and initial characterization of micromachined pressure sensors and micromachined jets (microjets) fabricated for use in macro flow control and other applications. In this work, the microfabrication technology was investigated to create a micromachined fluidic control system with a goal of application in practical fluids problems, such as UAV (Unmanned Aerial Vehicle)-scale aerodynamic control. Approaches of this work include : (1) the development of suitable micromachined synthetic jets (microjets) as actuators, which obviate the need to physically extend micromachined structures into an external flow ; and (2) a non-silicon alternative micromachining fabrication technology based on metallic substrates and lamination (in addition to traditional MEMS technologies) which will allow the realization of larger scale, more robust structures and larger array active areas for fluidic systems. As an initial study, an array of MEMS pressure sensors and an array of MEMS modulators for orifice-based control of microjets have been fabricated, and characterized. Both pressure sensors and modulators have been built using stainless steel as a substrate and a combination of lamination and traditional micromachining processes as fabrication technologies.

  5. Etching characteristics of Si{110} in 20 wt% KOH with addition of hydroxylamine for the fabrication of bulk micromachined MEMS

    Science.gov (United States)

    Rao, A. V. Narasimha; Swarnalatha, V.; Pal, P.

    2017-12-01

    Anisotropic wet etching is a most widely employed for the fabrication of MEMS/NEMS structures using silicon bulk micromachining. The use of Si{110} in MEMS is inevitable when a microstructure with vertical sidewall is to be fabricated using wet anisotropic etching. In most commonly employed etchants (i.e. TMAH and KOH), potassium hydroxide (KOH) exhibits higher etch rate and provides improved anisotropy between Si{111} and Si{110} planes. In the manufacturing company, high etch rate is demanded to increase the productivity that eventually reduces the cost of end product. In order to modify the etching characteristics of KOH for the micromachining of Si{110}, we have investigated the effect of hydroxylamine (NH2OH) in 20 wt% KOH solution. The concentration of NH2OH is varied from 0 to 20% and the etching is carried out at 75 °C. The etching characteristics which are studied in this work includes the etch rates of Si{110} and silicon dioxide, etched surface morphology, and undercutting at convex corners. The etch rate of Si{110} in 20 wt% KOH + 15% NH2OH solution is measured to be four times more than that of pure 20 wt% KOH. Moreover, the addition of NH2OH increases the undercutting at convex corners and enhances the etch selectivity between Si and SiO2.

  6. Two-dimensional capacitive micromachined ultrasonic transducer (CMUT) arrays for a miniature integrated volumetric ultrasonic imaging system

    Science.gov (United States)

    Zhuang, Xuefeng; Wygant, Ira O.; Yeh, David T.; Nikoozadeh, Amin; Oralkan, Omer; Ergun, Arif S.; Cheng, Ching-Hsiang; Huang, Yongli; Yaralioglu, Goksen G.; Khuri-Yakub, Butrus T.

    2005-04-01

    We have designed, fabricated, and characterized two-dimensional 16x16-element capacitive micromachined ultrasonic transducer (CMUT) arrays. The CMUT array elements have a 250-μm pitch, and when tested in immersion, have a 5 MHz center frequency and 99% fractional bandwidth. The fabrication process is based on standard silicon micromachining techniques and therefore has the advantages of high yield, low cost, and ease of integration. The transducers have a Si3N4 membrane and are fabricated on a 400-μm thick silicon substrate. A low parasitic capacitance through-wafer via connects each CMUT element to a flip-chip bond pad on the back side of the wafer. Each through wafer via is 20 μm in diameter and 400 μm deep. The interconnects form metal-insulator-semiconductor (MIS) junctions with the surrounding high-resistivity silicon substrate to establish isolation and to reduce parasitic capacitance. Each through-wafer via has less than 0.06 pF of parasitic capacitance. We have investigated a Au-In flip-chip bonding process to connect the 2D CMUT array to a custom integrated circuit (IC) with transmit and receive electronics. To develop this process, we fabricated fanout structures on silicon, and flip-chip bonded these test dies to a flat surface coated with gold. The average series resistance per bump is about 3 Ohms, and 100% yield is obtained for a total of 30 bumps.

  7. Fly's proprioception-inspired micromachined strain-sensing structure: idea, design, modeling and simulation, and comparison with experimental results

    Science.gov (United States)

    Wicaksono, D. H. B.; Zhang, L.-J.; Pandraud, G.; French, P. J.; Vincent, J. F. V.

    2006-04-01

    A new strain-sensing structure inspired from insect's (especially the Fly) propricoception sensor is devised. The campaniform sensillum is a strain-sensing microstructure with very high sensitivity despite its small dimension (diameter ~10 µm in a relatively stiff material of insect's exocuticle (E = ~109 Pa). Previous work shows that the high sensitivity of this structure towards strain is due to its membrane-in-recess- and strainconcentrating- hole- features. Based on this inspiration, we built similar structure using silicon micromachining technology. Then a simple characterisation setup was devised. Here, we present briefly, finite-element modeling and simulation based on this actual sample preparation for the characterisation. As comparison and also to understand mechanical features responsible for the strain-sensitivity, we performed the modeling on different mechanical structures: bulk chunk, blind-hole, thorugh-hole, surface membrane, and membrane-in-recess. The actual experimental characterisation was performed previously using optical technique to membranein- recess micromachined Si structure. The FEM simulation results confirm that the bending stress and strain are concentrated in the hole-vicinity. The membrane inside the hole acts as displacement transducer. The FEM is in conformity with previous analytical results, as well as the optical characterisation result. The end goal is to build a new type MEMS strain sensor.

  8. Compact Micromachined Infrared Bandpass Filters for Planetary Spectroscopy

    Science.gov (United States)

    Merrell, Willie C., II; Aslam, Shahid; Brown, Ari D.; Chervenak, James A.; Huang, Wei-Chung; Quijada, Manuel; Wollack, Edward

    2011-01-01

    The future needs of space based observational planetary and astronomy missions include low mass and small volume radiometric instruments that can operate in high radiation and low temperature environments. Here we focus on a central spectroscopic component, the bandpass filter. We model the bandpass response of the filters to target the wavelength of the resonance peaks at 20, 40, and 60 micrometers and report good agreement between the modeled and measured response. We present a technique of using common micromachining processes for semiconductor fabrication to make compact, free standing resonant metal mesh filter arrays with silicon support frames. The process can accommodate multiple detector array architectures and the silicon frame provides lightweight mechanical support with low form factor. We also present a conceptual hybridization of the filters with a detector array.

  9. Characterization of bulk-micromachined direct-bonded silicon nanofilters

    Science.gov (United States)

    Tu, Jay K.; Huen, Tony; Szema, Robert; Ferrari, Mauro

    1998-03-01

    The ability to separate 30-100 nm particles - nanofiltration - is critical for many biomedical applications. Where this filtration needs to be absolute, such as for viral elimination in the blood fractionation process, the large variations in pore size found with conventional polymeric filters can lead to the unwanted presence of viruses in the filtrate. To overcome this problem, we have developed a filter with micromachined channels sandwiched between two bonded silicon wafers. These channels are formed through the selective deposition and then removal of a thermally-grown oxide, the thickness of which can be controlled to +/- 4 percent for 30 nm pores. In this paper, we will present both the gas and liquid characterization, and the filtration studies done on 44 and 100 nm beads.

  10. Performance Enhancement of the Patch Antennas Applying Micromachining Technology

    Directory of Open Access Journals (Sweden)

    Mohamed N. Azermanesh

    2007-09-01

    Full Text Available This paper reports on the application of micromachining technology for performance enhancement of two types of compact antennas which are becoming a common practice in microsystems. Shorted patch antennas (SPA and folded shorted patch antennas operating in the 5-6 GHz ISM band, with intended application in short-range wireless communications, are considered. The electrical length of antennas are modified by etching the substrate of the antennas, thus providing a new degree of freedom to control the antenna operating properties, which is the main novelty of our work. The gain and bandwidth of the antennas are increased by increasing the etching depth. However, etching the substrate affects the operating frequency as well. To keep the operating frequency at a pre-specified value, the dimension of the antennas must be increased by deepening the etching depth. Therefore, a trade off between the performance enhancement of the antennas and the dimensional enlargement is required.

  11. Micromachined high-performance RF passives in CMOS substrate

    International Nuclear Information System (INIS)

    Li, Xinxin; Ni, Zao; Gu, Lei; Wu, Zhengzheng; Yang, Chen

    2016-01-01

    This review systematically addresses the micromachining technologies used for the fabrication of high-performance radio-frequency (RF) passives that can be integrated into low-cost complementary metal-oxide semiconductor (CMOS)-grade (i.e. low-resistivity) silicon wafers. With the development of various kinds of post-CMOS-compatible microelectromechanical systems (MEMS) processes, 3D structural inductors/transformers, variable capacitors, tunable resonators and band-pass/low-pass filters can be compatibly integrated into active integrated circuits to form monolithic RF system-on-chips. By using MEMS processes, including substrate modifying/suspending and LIGA-like metal electroplating, both the highly lossy substrate effect and the resistive loss can be largely eliminated and depressed, thereby meeting the high-performance requirements of telecommunication applications. (topical review)

  12. A Micro-Machined Gyroscope for Rotating Aircraft

    Directory of Open Access Journals (Sweden)

    Fuxue Zhang

    2012-07-01

    Full Text Available In this paper we present recent work on the design, fabrication by silicon micromachining, and packaging of a new gyroscope for stabilizing the autopilot of rotating aircraft. It operates based on oscillation of the silicon pendulum between two torsion girders for detecting the Coriolis force. The oscillation of the pendulum is initiated by the rolling and deflecting motion of the rotating carrier. Therefore, the frequency and amplitude of the oscillation are proportional to the rolling frequency and deflecting angular rate of the rotating carrier, and are measured by the sensing electrodes. A modulated pulse with constant amplitude and unequal width is obtained by a linearizing process of the gyroscope output signal and used to control the deflection of the rotating aircraft. Experimental results show that the gyroscope has a resolution of 0.008 °/s and a bias of 56.18 °/h.

  13. Capacitive micromachined ultrasonic transducers for medical imaging and therapy

    Science.gov (United States)

    Khuri-Yakub, Butrus T.; Oralkan, Ömer

    2011-05-01

    Capacitive micromachined ultrasonic transducers (CMUTs) have been subject to extensive research for the last two decades. Although they were initially developed for air-coupled applications, today their main application space is medical imaging and therapy. This paper first presents a brief description of CMUTs, their basic structure and operating principles. Our progression of developing several generations of fabrication processes is discussed with an emphasis on the advantages and disadvantages of each process. Monolithic and hybrid approaches for integrating CMUTs with supporting integrated circuits are surveyed. Several prototype transducer arrays with integrated front-end electronic circuits we developed and their use for 2D and 3D, anatomical and functional imaging, and ablative therapies are described. The presented results prove the CMUT as a micro-electro-mechanical systems technology for many medical diagnostic and therapeutic applications.

  14. Capacitive micromachined ultrasonic transducers for medical imaging and therapy

    International Nuclear Information System (INIS)

    Khuri-Yakub, Butrus T; Oralkan, Ömer

    2011-01-01

    Capacitive micromachined ultrasonic transducers (CMUTs) have been subject to extensive research for the last two decades. Although they were initially developed for air-coupled applications, today their main application space is medical imaging and therapy. This paper first presents a brief description of CMUTs, their basic structure and operating principles. Our progression of developing several generations of fabrication processes is discussed with an emphasis on the advantages and disadvantages of each process. Monolithic and hybrid approaches for integrating CMUTs with supporting integrated circuits are surveyed. Several prototype transducer arrays with integrated front-end electronic circuits we developed and their use for 2D and 3D, anatomical and functional imaging, and ablative therapies are described. The presented results prove the CMUT as a micro-electro-mechanical systems technology for many medical diagnostic and therapeutic applications

  15. Compact Micromachined Bandpass Filters for Infrared Planetary Spectroscopy

    Science.gov (United States)

    Brown, Ari D.; Aslam, Shahid; Chervenak, James A.; Huang, Wei-Chung; Merrell, Willie; Quijada, Manuel

    2011-01-01

    The thermal instrument strawman payload of the Jupiter Europa Orbiter on the Europa Jupiter Science Mission will map out thermal anomalies, the structure, and atmospheric conditions of Europa and Jupiter within the 7-100 micron spectral range. One key requirement for the payload is that the mass cannot exceed 3.7 kg. Consequently, a new generation of light-weight miniaturized spectrometers needs to be developed. On the path toward developing these spectrometers is development of ancillary miniaturized spectroscopic components. In this paper, we present a strategy for making radiation hard and low mass FIR band pass metal mesh filters. Our strategy involves using MEMS-based fabrication techniques, which will permit the quasi-optical filter structures to be made with micron-scale precision. This will enable us to achieve tight control over both the pass band of the filter and the micromachined silicon support structure architecture, which will facilitate integration of the filters for a variety of applications.

  16. Micromachined Systems-on-a-Chip: Infrastructure, Technology and Applications

    Energy Technology Data Exchange (ETDEWEB)

    Allen, J. J.; Krygowski, T. W.; Miller, S. L.; Montague, S.; Rodgers, M. S.; Schriner, H.; Smith, J. H.; Sniegowski, J. J.

    1998-10-09

    A review is made of the infrastructure, technology and capabilities of Sandia National Laboratories for the development of micromechanical systems that have potential space applications. By incorporating advanced fabrication processes, such as chemical mechanical polishing, and several mechanical polysilicon levels, the range' of rrticromechanical systems that can be fabricated in these technologies is virtually limitless. Representative applications include a micro- engine driven mirror, and a micromachined lock. Using a novel integrated MEM!YCMOS technology, a six degree-of-freedom accelerometer/gyroscope system has been designed by researchers at U.C. Berkeley and fabricated on the same silicon chip as the CMOS control circuits to produce an integrated micro-navigational unit.

  17. Sub-band-gap laser micromachining of lithium niobate

    DEFF Research Database (Denmark)

    Christensen, F. K.; Müllenborn, Matthias

    1995-01-01

    Laser processing of insulators and semiconductors is usually realized using photon energies exceeding the band-gap energy. This makes laser processing of insulators difficult since high photon energies typically require either a pulsed laser or a frequency-doubled continuous-wave laser. A new...... method is reported which enables us to do laser processing of lithium niobate using sub-band-gap photons. Using high scan speeds, moderate power densities, and sub-band-gap photon energies results in volume removal rates in excess of 106µm3/s. This enables fast micromachining of small piezoelectric...... structures, or simple etching of grooves for precision positioning of optical fibers. ©1995 American Institute of Physics....

  18. Q-Switched Nd: YAG Laser Micro-Machining System

    International Nuclear Information System (INIS)

    Messaoud, S.; Allam, A.; Siserir, F.; Bouceta, Y.; Kerdja, T.; Ouadjaout, D.

    2008-01-01

    In this paper, we present the design of a low cost Q-switched Nd: YAG laser micro-machining system for photo masks fabrication. It consists of: Nd:YAG laser source, beam delivery system, X-Y table, PC, The CCD camera and TV monitor. The synchronization between the laser source and the X-Y table is realised by NI PCI-7342, the two axis MID-7602 and LabVIEW based program. The first step of this work consists of engraving continuous and discontinuous lines on a thin film metal with a 100 μm resolution by using the YG 980 Quantel Q-switched Nd:YAG laser.

  19. Micromachined hot-wire thermal conductivity probe for biomedical applications.

    Science.gov (United States)

    Yi, Ming; Panchawagh, Hrishikesh V; Podhajsky, Ronald J; Mahajan, Roop L

    2009-10-01

    This paper presents the design, fabrication, numerical simulation, and experimental validation of a micromachined probe that measures thermal conductivity of biological tissues. The probe consists of a pair of resistive line heating elements and resistance temperature detector sensors, which were fabricated by using planar photolithography on a glass substrate. The numerical analysis revealed that the thermal conductivity and diffusivity can be determined by the temperature response induced by the uniform heat flux in the heating elements. After calibrating the probe using a material (agar gel) of known thermal conductivity, the probe was deployed to calculate the thermal conductivity of Crisco. The measured value is in agreement with that determined by the macro-hot-wire probe method to within 3%. Finally, the micro thermal probe was used to investigate the change of thermal conductivity of pig liver before and after RF ablation treatment. The results show an increase in thermal conductivity of liver after the RF ablation.

  20. Characterization of a Silicon-Micromachined Thermal Shear-Stress Sensor

    National Research Council Canada - National Science Library

    Sheplak, Mark; Chandrasekaran, Venkataraman; Cain, Anthony; Nishida, Toshikazu; Cattafesta, Louis N

    2002-01-01

    A detailed characterization is presented of a silicon-micromachined thermal shear-stress sensor employing a thin-film platinum-sensing element on top of a silicon-nitride membrane that is stretched over a vacuum cavity...

  1. Laser micro-machined semi-slinky like MEMS structures: Novel interface coolers

    Science.gov (United States)

    Çelen, Serap

    2012-10-01

    Laser micro-machining has recently been considered a precision and reproducible manufacturing technique in MEMS fabrication because of the superior characteristics of a focused laser beam. It is not only a unique tool but also an invisible optical drill. The aim of the present paper is two-fold: to manufacture novel miniaturized titanium 3D MEMS surface structures in order to increase the cooling performance. Second is to find the behaviors of the operational parameters which controlling the laser-material interaction mechanisms and also suggest the best adjustments in order to achieve this novel semi-slinky like spiral MEMS surface structures with using a 20 W ytterbium fiber laser. Pure titanium micro-MEMS product which has novel interface coolers was manufactured using a ytterbium fiber laser (λ=1060 nm) with 40 ns pulse duration. Best adjustments were, respectively, the pulse duration: 40 ns, the pulse energy: 0.4 mJ, the laser scanning speed: 336.1 mm/s, the peak power density: 17.46 * 108 W/cm2.

  2. Study of surfactant-added TMAH for applications in DRIE and wet etching-based micromachining

    Science.gov (United States)

    Tang, B.; Shikida, M.; Sato, K.; Pal, P.; Amakawa, H.; Hida, H.; Fukuzawa, K.

    2010-06-01

    In this paper, etching anisotropy is evaluated for a number of different crystallographic orientations of silicon in a 0.1 vol% Triton-X-100 added 25 wt% tetramethylammonium hydroxide (TMAH) solution using a silicon hemisphere. The research is primarily aimed at developing advanced applications of wet etching in microelectromechanical systems (MEMS). The etching process is carried out at different temperatures in the range of 61-81 °C. The etching results of silicon hemisphere and different shapes of three-dimensional structures in {1 0 0}- and {1 1 0}-Si surfaces are analyzed. Significantly important anisotropy, different from a traditional etchant (e.g. pure KOH and TMAH), is investigated to extend the applications of the wet etching process in silicon bulk micromachining. The similar etching behavior of exact and vicinal {1 1 0} and {1 1 1} planes in TMAH + Triton is utilized selectively to remove the scalloping from deep reactive-ion etching (DRIE) etched profiles. The direct application of the present research is demonstrated by fabricating a cylindrical lens with highly smooth etched surface finish. The smoothness of a micro-lens at different locations is measured qualitatively by a scanning electron microscope and quantitatively by an atomic force microscope. The present paper provides a simple and effective fabrication method of the silicon micro-lens for optical MEMS applications.

  3. Free-standing double-layer terahertz band-pass filters fabricated by femtosecond laser micro-machining.

    Science.gov (United States)

    Lin, Yanzhang; Yao, Haizi; Ju, Xuewei; Chen, Ying; Zhong, Shuncong; Wang, Xiangfeng

    2017-10-16

    We report on the fabrication and transmission properties of free-standing single-layer and double-layer THz bandpass filters. These filters are fabricated on aluminum foils using femtosecond laser micro-machining. The aluminum foils are periodically patterned with cross apertures with a total area of 1.75×1.75 cm 2 , also known as frequency-selective surfaces. Their terahertz transmission properties were simulated using the FDTD method and measured using a time-domain terahertz spectroscopy system. The simulation results agree with the measurements results very well. The performance of single-layer bandpass filters is as good as the commercial equivalents on the market. The double-layer filters show extraordinary transmission peaks with changing spacing between the two layers. We show the contour map of the electric field distribution across the apertures, and ascribe the new transmission peaks to the interference and coupling of surface plasmon polaritons between the two layers.

  4. Micromachined thin-film sensors for SOI-CMOS co-integration

    CERN Document Server

    Laconte, Jean; Raskin, Jean-Pierre

    2006-01-01

    Co-integration of MEMS and MOS in SOI technology is promising and well demonstrated hereThe impact of Micromachining on SOI devices is deeply analyzed for the first timeInclude extensive TMAH etching, residual stress, microheaters, gas-flow sensors reviewResidual stresses in thin films need to be more and more monitored in MEMS designsTMAH micromachining is an attractive alternative to KOH.

  5. Sewage sludge irradiators: Batch and continuous flow

    International Nuclear Information System (INIS)

    Lavale, D.S.; George, J.R.; Shah, M.R.; Rawat, K.P.

    1998-01-01

    The potential threat to the environment imposed by high pathogenic organism content in municipal wastewater, especially the sludge and the world-wide growing aspirations for a cleaner, salubrious environment have made it mandatory for the sewage and sludge to undergo treatment, prior to their ultimate disposal to mother nature. Incapabilities associated with the conventional wastewater treatments to mitigate the problem of microorganisms have made it necessary to look for other alternatives, radiation treatment being the most reliable, rapid and environmentally sustainable of them. To promote the use of radiation for the sludge hygienization, Department of Atomic Energy has endeavoured to set up an indigenous, Sludge Hygienization Research Irradiator (SHRI) in the city of Baroda. Designed for 18.5 PBq of 60 Co to disinfect the digested sludge, the irradiator has additional provision for treatment of effluent and raw sewage. From engineering standpoint, all the subsystems have been functioning satisfactorily since its commissioning in 1990. Prolonged studies, spanning over a period of six years, primarily focused on inactivation of microorganism revealed that 3 kGy dose of gamma radiation is adequate to make the sludge pathogen and odour-free. A dose of 1.6 kGy in raw sewage and 0.5 kGy in effluent reduced coliform counts down to the regulatory discharge limits. These observations reflect a possible cost-effective solution to the burgeoning problem of surface water pollution across the globe. In the past, sub 37 PBq 60 Co batch irradiators have been designed and commissioned successfully for the treatment of sludge. Characterized with low dose delivery rates they are well-suited for treating low volumes of sludge in batches. Some concepts of continuous flow 60 Co irradiators having larger activities, yet simple and economic in design, are presented in the paper

  6. Hypersonic force measurements using internal balance based on optical micromachined Fabry-Perot interferometry

    Science.gov (United States)

    Qiu, Huacheng; Min, Fu; Zhong, Shaolong; Song, Xin; Yang, Yanguang

    2018-03-01

    Force measurements using wind tunnel balance are necessary for determining a variety of aerodynamic performance parameters, while the harsh environment in hypersonic flows requires that the measurement instrument should be reliable and robust, in against strong electromagnetic interference, high vacuum, or metal (oxide) dusts. In this paper, we demonstrated a three-component internal balance for hypersonic aerodynamic force measurements, using novel optical micromachined Fabry-Perot interferometric (FPI) strain gauges as sensing elements. The FPI gauges were fabricated using Micro-Opto-Electro-Mechanical Systems (MOEMS) surface and bulk fabrication techniques. High-reflectivity coatings are used to form a high-finesse Fabry-Perot cavity, which benefits a high resolution. Antireflective and passivation coatings are used to reduce unwanted interferences. The FPI strain gauge based balance has been calibrated and evaluated in a Mach 5 hypersonic flow. The results are compared with the traditional technique using the foil resistive strain gauge balance, indicating that the proposed balance based on the MOEMS FPI strain gauge is reliable and robust and is potentially suitable for the hypersonic wind tunnel harsh environment.

  7. Planar Indium Tin Oxide Heater for Improved Thermal Distribution for Metal Oxide Micromachined Gas Sensors.

    Science.gov (United States)

    Çakır, M Cihan; Çalışkan, Deniz; Bütün, Bayram; Özbay, Ekmel

    2016-09-29

    Metal oxide gas sensors with integrated micro-hotplate structures are widely used in the industry and they are still being investigated and developed. Metal oxide gas sensors have the advantage of being sensitive to a wide range of organic and inorganic volatile compounds, although they lack selectivity. To introduce selectivity, the operating temperature of a single sensor is swept, and the measurements are fed to a discriminating algorithm. The efficiency of those data processing methods strongly depends on temperature uniformity across the active area of the sensor. To achieve this, hot plate structures with complex resistor geometries have been designed and additional heat-spreading structures have been introduced. In this work we designed and fabricated a metal oxide gas sensor integrated with a simple square planar indium tin oxide (ITO) heating element, by using conventional micromachining and thin-film deposition techniques. Power consumption-dependent surface temperature measurements were performed. A 420 °C working temperature was achieved at 120 mW power consumption. Temperature distribution uniformity was measured and a 17 °C difference between the hottest and the coldest points of the sensor at an operating temperature of 290 °C was achieved. Transient heat-up and cool-down cycle durations are measured as 40 ms and 20 ms, respectively.

  8. Microfabrication in free-standing gallium nitride using UV laser micromachining

    International Nuclear Information System (INIS)

    Gu, E.; Howard, H.; Conneely, A.; O'Connor, G.M.; Illy, E.K.; Knowles, M.R.H.; Edwards, P.R.; Martin, R.W.; Watson, I.M.; Dawson, M.D.

    2006-01-01

    Gallium nitride (GaN) and related alloys are important semiconductor materials for fabricating novel photonic devices such as ultraviolet (UV) light-emitting diodes (LEDs) and vertical cavity surface-emitting lasers (VCSELs). Recent technical advances have made free-standing GaN substrates available and affordable. However, these materials are strongly resistant to wet chemical etching and also, low etch rates restrict the use of dry etching. Thus, to develop alternative high-resolution processing for these materials is increasingly important. In this paper, we report the fabrication of microstructures in free-standing GaN using pulsed UV lasers. An effective method was first developed to remove the re-deposited materials due to the laser machining. In order to achieve controllable machining and high resolution in GaN, machining parameters were carefully optimised. Under the optimised conditions, precision features such as holes (through holes, blind or tapered holes) on a tens of micrometer length scale have been machined. To fabricate micro-trenches in GaN with vertical sidewalls and a flat bottom, different process strategies of laser machining were tested and optimised. Using this technique, we have successfully fabricated high-quality micro-trenches in free-standing GaN with various widths and depths. The approach combining UV laser micromachining and other processes is also discussed. Our results demonstrate that the pulsed UV laser is a powerful tool for fabricating precision microstructures and devices in gallium nitride

  9. Planar Indium Tin Oxide Heater for Improved Thermal Distribution for Metal Oxide Micromachined Gas Sensors

    Directory of Open Access Journals (Sweden)

    M. Cihan Çakır

    2016-09-01

    Full Text Available Metal oxide gas sensors with integrated micro-hotplate structures are widely used in the industry and they are still being investigated and developed. Metal oxide gas sensors have the advantage of being sensitive to a wide range of organic and inorganic volatile compounds, although they lack selectivity. To introduce selectivity, the operating temperature of a single sensor is swept, and the measurements are fed to a discriminating algorithm. The efficiency of those data processing methods strongly depends on temperature uniformity across the active area of the sensor. To achieve this, hot plate structures with complex resistor geometries have been designed and additional heat-spreading structures have been introduced. In this work we designed and fabricated a metal oxide gas sensor integrated with a simple square planar indium tin oxide (ITO heating element, by using conventional micromachining and thin-film deposition techniques. Power consumption–dependent surface temperature measurements were performed. A 420 °C working temperature was achieved at 120 mW power consumption. Temperature distribution uniformity was measured and a 17 °C difference between the hottest and the coldest points of the sensor at an operating temperature of 290 °C was achieved. Transient heat-up and cool-down cycle durations are measured as 40 ms and 20 ms, respectively.

  10. Micromachined Silicon Stimulating Probes with CMOS Circuitry for Use in the Central Nervous System

    Science.gov (United States)

    Tanghe, Steven John

    1992-01-01

    Electrical stimulation in the central nervous system is a valuable technique for studying neural systems and is a key element in the development of prostheses for deafness and other disorders. This thesis presents a family of multielectrode probe structures, fulfilling the need for chronic multipoint stimulation tools essential for interfacing to the highly complex neural networks in the brain. These probes are batch-fabricated on silicon wafers, employing photoengraving techniques to precisely control the electrode site and array geometries and to allow the integration of on-chip CMOS circuitry for signal multiplexing and stimulus current generation. Silicon micromachining is used to define the probe shapes, which have typical shank dimensions of 3 mm in length by 100 mu m in width by 15 μm in thickness. Each shank supports up to eight planar iridium oxide electrode sites capable of delivering charge densities in excess of 3 mC/cm^2 during current pulse stimulation. Three active probe circuits have been designed with varied complexity and capability. All three can deliver biphasic stimulus currents through 16 sites using only 5 external leads, and they are all compatible with the same external control system. The most complex design interprets site addresses and stimulus current amplitudes from 16-bit words shifted into the probe at 4 MHz. Sixteen on-chip, biphasic, 8-bit digital-to-analog converters deliver analog stimulus currents in the range of +/- 254 muA to any combination of electrode sites. These DACs exhibit full-scale internal linearity to better than +/-1/2 LSB and can be calibrated by varying the positive power supply voltage. The entire probe circuit dissipates only 80 muW from +/-5 V supplies when not delivering stimulus currents, it includes several safety features, and is testable from the input pads. Test results from the fabricated circuits indicate that they all function properly at clocking frequencies as high as 10 MHz, meeting or exceeding

  11. Fiscal 1996 report on technological results. R and D on micromachine technology; 1996 nendo micromachine gijutsu no kenkyu kaihatsu seika hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-03-01

    Researches on basic element technology of micromachines are conducted that operate autonomously in a narrow small part in a complicated apparatus or in vivo. The areas of activity are (1) research on micromachine systems, (2) a subminiature liquid synthesizing system, and (3) comprehensive investigation and research. In (1), the researches were carried out on the miniaturization and functional combination of a micro laser catheter and a micro tactile sensor catheter, which are the primary components of a coeliac diagnostic and therapeutic system, a 'micro catheter for cerebral blood vessel/treatment', as a micromachine system in the medical field. In (2), R and D was conducted on a system element technology assuming it contributed to a subminiature liquid synthesizing system capable of preparing various liquids including pharmaceuticals accurately with a trace amount. In (3), examination was made on the application area of a micromachine system with priority given to a medical field and also on technological subjects to be tapped, as well as on the contents of (2), with a device installed for evaluating the operating characteristic of a distribution type fluid actuator as needed for the development. (NEDO)

  12. Family based dispatching with batch availability

    NARCIS (Netherlands)

    van der Zee, D.J.

    2013-01-01

    Family based dispatching rules seek to lower set-up frequencies by grouping (batching) similar types of jobs for joint processing. Hence shop flow times may be improved, as less time is spent on set-ups. Motivated by an industrial project we study the control of machines with batch availability,

  13. Nucleation and crystal growth in batch crystallizers

    NARCIS (Netherlands)

    Janse, A.H.

    1977-01-01

    The aim of the present work is to gain knowledge of the mechanism of formation of the crystal size distribution in batch crystallizers in order to give directives for design and operation of batch crystallizers. The crystal size distribution is important for the separation of crystals and mother

  14. Automatic endpoint determination for batch tea dryers

    NARCIS (Netherlands)

    Temple, S.J.; Boxtel, van A.J.B.

    2001-01-01

    A laboratory batch fluid-bed dryer was developed for handling small samples of tea for experimental batch manufacture, and this dryer required a means of stopping drying when the process was complete. A control system was devised which requires only the initial weight of the sample to be entered

  15. Supervision of Fed-Batch Fermentations

    DEFF Research Database (Denmark)

    Gregersen, Lars; Jørgensen, Sten Bay

    1999-01-01

    Process faults may be detected on-line using existing measurements based upon modelling that is entirely data driven. A multivariate statistical model is developed and used for fault diagnosis of an industrial fed-batch fermentation process. Data from several (25) batches are used to develop a mo...

  16. Giant flexoelectric polarization in a micromachined ferroelectric diaphragm

    KAUST Repository

    Wang, Zhihong

    2012-08-14

    The coupling between dielectric polarization and strain gradient, known as flexoelectricity, becomes significantly large on the micro- and nanoscale. Here, it is shown that giant flexoelectric polarization can reverse remnant ferroelectric polarization in a bent Pb(Zr0.52Ti0.48) O3 (PZT) diaphragm fabricated by micromachining. The polarization induced by the strain gradient and the switching behaviors of the polarization in response to an external electric field are investigated by observing the electromechanical coupling of the diaphragm. The method allows determination of the absolute zero polarization state in a PZT film, which is impossible using other existing methods. Based on the observation of the absolute zero polarization state and the assumption that bending of the diaphragm is the only source of the self-polarization, the upper bound of flexoelectric coefficient of PZT film is calculated to be as large as 2.0 × 10-4 C m -1. The strain gradient induced by bending the diaphragm is measured to be on the order of 102 m-1, three orders of magnitude larger than that obtained in the bulk material. Because of this large strain gradient, the estimated giant flexoelectric polarization in the bent diaphragm is on the same order of magnitude as the normal remnant ferroelectric polarization of PZT film. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Review of piezoelectric micromachined ultrasonic transducers and their applications

    Science.gov (United States)

    Jung, Joontaek; Lee, Wonjun; Kang, Woojin; Shin, Eunjung; Ryu, Jungho; Choi, Hongsoo

    2017-11-01

    In recent decades, micromachined ultrasonic transducers (MUTs) have been investigated as an alternative to conventional piezocomposite ultrasonic transducers, primarily due to the advantages that microelectromechanical systems provide. Miniaturized ultrasonic systems require ultrasonic transducers integrated with complementary metal-oxide-semiconductor circuits. Hence, piezoelectric MUTs (pMUTs) and capacitive MUTs (cMUTs) have been developed as the most favorable solutions. This paper reviews the basic equations to understand the characteristics of thin-film-based piezoelectric devices and presents recent research on pMUTs, including current approaches and limitations. Methods to improve the coupling coefficient of pMUTs are also investigated, such as device structure, materials, and fabrication techniques. The device structure improvements include multielectrode pMUTs, partially clamped boundary conditions, and 3D pMUTs (curved and domed types), where the latter can provide an electromechanical coupling coefficient of up to 45%. The piezoelectric coefficient (e 31) can be increased by controlling the crystal texture (seed layer of γ-Al2O3), using single-crystal (PMN-PT) materials, or control of residual stresses (using SiO2 layer). Arrays of pMUTs can be implemented for various applications including intravascular ultrasound, fingerprint sensors, rangefinders in air, and wireless power supply systems. pMUTs are expected to be an ideal solution for applications such as mobile biometric security (fingerprint sensors) and rangefinders due to their superior power efficiency and compact size.

  18. Development of capacitive micromachined ultrasonic transducer for noncontact ultrasonic detection

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ki Bok; Ahn, Bong Young; Park, Hae Won; Kim, Young Joo; Lee, Seung Seok [Center for Environment and Safrty Measurement, KRISS, Daejeon (Korea, Republic of)

    2004-11-15

    In this study, the capacitive micromachined ultrasonic transducer (cMUT) was developed. Theoretical analysis and finite element analysis of the behavior of membrane (such as resonance frequency, membrane deflection, collapse deflection and collapse voltage) of the cMUT were performed. The design parameters of the cMUT were estimated and are the dimension and thickness of membrane, thickness of sacrificial layer, thickness and size of electrode, size of active element and so on. With the micro-fabrication process, the cMUT was fabricated on the silicon wafer. To measure the membrane displacement of cMUT, the Michelson phase modulation fiber interferometer was constructed. The measured membrane displacement was good agreed with the result of finite element analysis. To estimate the ultrasonic wave generated by the cMUT, the ultrasonic transceiver system was constructed. The developed cMUT shows a good performance and hence will be widely used to the filed of non-contact ultrasonic application.

  19. Capacitive micromachined ultrasonic transducers (CMUTs) for photoacoustic imaging

    Science.gov (United States)

    Vaithilingam, Srikant; Wygant, Ira O.; Kuo, Paulina S.; Zhuang, Xuefeng; Oralkan, Ömer; Olcott, Peter D.; Khuri-Yakub, Butrus T.

    2006-02-01

    In photoacoustic (optoacoustic) medical imaging, short laser pulses irradiate absorbing structures found in tissue, such as blood vessels, causing brief thermal expansions that in turn generate ultrasound waves. These ultrasound waves which correspond to the optical absorption distribution were imaged using a two dimensional array of capacitive micromachined ultrasonic transducers (CMUTs). Advantages of CMUT technology for photoacoustic imaging include the ease of integration with electronics, ability to fabricate large two dimensional arrays, arrays with arbitrary geometries, wide-bandwidth arrays and high-frequency arrays. In this study, a phantom consisting of three 0.86-mm inner diameter polyethylene tubes inside a tissue mimicking material was imaged using a 16 x 16 element CMUT array. The center tube was filled with India-ink to provide optical contrast. Traditional pulse-echo data as well as photoacoustic image data were taken. 2D cross-sectional slices and 3D volume rendered images are shown. Simple array tiling was attempted, whereby a 48 x 48 element array was simulated, to illustrate the advantages of larger arrays. Finally, the sensitivity of the photoacoustics setup to the concentration of ink in the tube was also explored. For the sensitivity experiment a different phantom consisting of only one 1.14-mm inner diameter polyethylene tube inside a tissue mimicking material was used. The concentration of the ink inside the tube was varied and images were taken.

  20. Capacitive micromachined ultrasound transducer (cMUT) for immunosensor design.

    Science.gov (United States)

    Ramanaviciene, Almira; Virzonis, Darius; Vanagas, Gailius; Ramanavicius, Arūnas

    2010-07-01

    An affinity sensor based on a capacitive micromachined ultrasound transducer (cMUT) is reported by this Communication. The cMUT micromembrane arrays modified with adsorbed bovine leukemia virus protein gp51 were applied as a biological recognition part. The cMUT-based sensor is shown to be sensitive to the antibodies against bovine leukemia virus protein gp51 (anti-gp51). Two different concentrations of anti-gp51-containing samples and one blank sample without anti-gp51 were tested. The sensitivity of cMUT-based immunosensor is comparable with the sensitivity of a quartz microbalance-based immunosensor. The cMUT array provides a multi-channel system for the measurement of analytical signal. Moreover, two different characteristics--the resonance frequency shift (Deltaf) and the shift of the real part of the electromechanical impedance (DeltaRe)--could have been evaluated simultaneously. Both analytical signals are informative and can be applied for the estimation of immune complex formation. We found the performance of such a system being potentially superior over some other immunosensing techniques. It is more rapid than electrochemical techniques and provides two different informative parameters.

  1. Singulation for imaging ring arrays of capacitive micromachined ultrasonic transducers

    International Nuclear Information System (INIS)

    Chang, Chienliu; Moini, Azadeh; Nikoozadeh, Amin; Sarioglu, Ali Fatih; Apte, Nikhil; Zhuang, Xuefeng; Khuri-Yakub, Butrus T

    2014-01-01

    Singulation of MEMS is a critical step in the transition from wafer-level to die-level devices. As is the case for capacitive micromachined ultrasound transducer (CMUT) ring arrays, an ideal singulation must protect the fragile membranes from the processing environment while maintaining a ring array geometry. The singulation process presented in this paper involves bonding a trench-patterned CMUT wafer onto a support wafer, deep reactive ion etching (DRIE) of the trenches, separating the CMUT wafer from the support wafer and de-tethering the CMUT device from the CMUT wafer. The CMUT arrays fabricated and singulated in this process were ring-shaped arrays, with inner and outer diameters of 5 mm and 10 mm, respectively. The fabricated CMUT ring arrays demonstrate the ability of this method to successfully and safely singulate the ring arrays and is applicable to any arbitrary 2D shaped MEMS device with uspended microstructures, taking advantage of the inherent planar attributes of DRIE. (technical note)

  2. Radiation impedance of collapsed capacitive micromachined ultrasonic transducers.

    Science.gov (United States)

    Ozgurluk, Alper; Atalar, Abdullah; Köymen, Hayrettin; Olçum, Selim

    2012-06-01

    The radiation impedance of a capacitive micromachined ultrasonic transducer (CMUT) array is a critical parameter to achieve high performance. In this paper, we present a calculation of the radiation impedance of collapsed, clamped, circular CMUTs both analytically and using finite element method (FEM) simulations. First, we model the radiation impedance of a single collapsed CMUT cell analytically by expressing its velocity profile as a linear combination of special functions for which the generated pressures are known. For an array of collapsed CMUT cells, the mutual impedance between the cells is also taken into account. The radiation impedances for arrays of 7, 19, 37, and 61 circular collapsed CMUT cells for different contact radii are calculated both analytically and by FEM simulations. The radiation resistance of an array reaches a plateau and maintains this level for a wide frequency range. The variation of radiation reactance with respect to frequency indicates an inductance-like behavior in the same frequency range. We find that the peak radiation resistance value is reached at higher kd values in the collapsed case as compared with the uncollapsed case, where k is the wavenumber and d is the center-to-center distance between two neighboring CMUT cells.

  3. Development of capacitive micromachined ultrasonic transducer for noncontact ultrasonic detection

    International Nuclear Information System (INIS)

    Kim, Ki Bok; Ahn, Bong Young; Park, Hae Won; Kim, Young Joo; Lee, Seung Seok

    2004-01-01

    In this study, the capacitive micromachined ultrasonic transducer (cMUT) was developed. Theoretical analysis and finite element analysis of the behavior of membrane (such as resonance frequency, membrane deflection, collapse deflection and collapse voltage) of the cMUT were performed. The design parameters of the cMUT were estimated and are the dimension and thickness of membrane, thickness of sacrificial layer, thickness and size of electrode, size of active element and so on. With the micro-fabrication process, the cMUT was fabricated on the silicon wafer. To measure the membrane displacement of cMUT, the Michelson phase modulation fiber interferometer was constructed. The measured membrane displacement was good agreed with the result of finite element analysis. To estimate the ultrasonic wave generated by the cMUT, the ultrasonic transceiver system was constructed. The developed cMUT shows a good performance and hence will be widely used to the filed of non-contact ultrasonic application.

  4. Diamond-based capacitive micromachined ultrasonic transducers in immersion.

    Science.gov (United States)

    Cetin, Ahmet M; Bayram, Baris

    2013-02-01

    Diamond is a superior membrane material for capacitive micromachined ultrasonic transducers (CMUTs). By using ultrananocrystalline diamond (UNCD) membrane and plasma-activated wafer bonding technology, a single diamond-based circular CMUT is demonstrated and operated in immersion for the first time. The diamond-based CMUT, biased at 100 V, is excited with a 10-cycle burst of 36 V(p-p) sine signal at 3.5 MHz. Pressure generated on a 2-D plane coincident with the normal of the CMUT is measured using a broadband hydrophone. Peak-to-peak hydrophone voltage measurements along the scan area clearly indicate the main lobe and the side lobes, as theoretically predicted by our directivity function calculations. The peak-to-peak hydrophone voltage on the axial direction of the CMUT is found to be in agreement with our theoretical calculations in the Fraunhofer region (-45 mm CMUT is measured for a dc bias of 100 V, and ac excitation with 30-cycle bursts of 9, 36, and 54 V(p-p) sine signal. A peak response at 5.6 MHz is measured for all ac amplitudes. Overall, diamond is shown to be an applicable membrane for CMUT devices and applications.

  5. Receive-Noise Analysis of Capacitive Micromachined Ultrasonic Transducers.

    Science.gov (United States)

    Bozkurt, Ayhan; Yaralioglu, G Goksenin

    2016-11-01

    This paper presents an analysis of thermal (Johnson) noise received from the radiation medium by otherwise noiseless capacitive micromachined ultrasonic transducer (CMUT) membranes operating in their fundamental resonance mode. Determination of thermal noise received by multiple numbers of transducers or a transducer array requires the assessment of cross-coupling through the radiation medium, as well as the self-radiation impedance of the individual transducer. We show that the total thermal noise received by the cells of a CMUT has insignificant correlation, and is independent of the radiation impedance, but is only determined by the mass of each membrane and the electromechanical transformer ratio. The proof is based on the analytical derivations for a simple transducer with two cells, and extended to transducers with numerous cells using circuit simulators. We used a first-order model, which incorporates the fundamental resonance of the CMUT. Noise power is calculated by integrating over the entire spectrum; hence, the presented figures are an upper bound for the noise. The presented analyses are valid for a transimpedance amplifier in the receive path. We use the analysis results to calculate the minimum detectable pressure of a CMUT. We also provide an analysis based on the experimental data to show that output noise power is limited by and comparable to the theoretical upper limit.

  6. Encapsulation of Capacitive Micromachined Ultrasonic Transducers Using Viscoelastic Polymer

    Science.gov (United States)

    Lin, Der-Song; Zhuang, Xuefeng; Wong, Serena H.; Kupnik, Mario; Khuri-Yakub, Butrus Thomas

    2010-01-01

    The packaging of a medical imaging or therapeutic ultrasound transducer should provide protective insulation while maintaining high performance. For a capacitive micromachined ultrasonic transducer (CMUT), an ideal encapsulation coating would therefore require a limited and predictable change on the static operation point and the dynamic performance, while insulating the high dc and dc actuation voltages from the environment. To fulfill these requirements, viscoelastic materials, such as polydimethylsiloxane (PDMS), were investigated for an encapsulation material. In addition, PDMS, with a glass-transition temperature below room temperature, provides a low Young's modulus that preserves the static behavior; at higher frequencies for ultrasonic operation, this material becomes stiffer and acoustically matches to water. In this paper, we demonstrate the modeling and implementation of the viscoelastic polymer as the encapsulation material. We introduce a finite element model (FEM) that addresses viscoelasticity. This enables us to correctly calculate both the static operation point and the dynamic behavior of the CMUT. CMUTs designed for medical imaging and therapeutic ultrasound were fabricated and encapsulated. Static and dynamic measurements were used to verify the FEM and show excellent agreement. This paper will help in the design process for optimizing the static and the dynamic behavior of viscoelastic-polymer-coated CMUTs. PMID:21170294

  7. Singulation for imaging ring arrays of capacitive micromachined ultrasonic transducers

    Science.gov (United States)

    Chang, Chienliu; Moini, Azadeh; Nikoozadeh, Amin; Sarioglu, Ali Fatih; Apte, Nikhil; Zhuang, Xuefeng; Khuri-Yakub, Butrus T.

    2014-10-01

    Singulation of MEMS is a critical step in the transition from wafer-level to die-level devices. As is the case for capacitive micromachined ultrasound transducer (CMUT) ring arrays, an ideal singulation must protect the fragile membranes from the processing environment while maintaining a ring array geometry. The singulation process presented in this paper involves bonding a trench-patterned CMUT wafer onto a support wafer, deep reactive ion etching (DRIE) of the trenches, separating the CMUT wafer from the support wafer and de-tethering the CMUT device from the CMUT wafer. The CMUT arrays fabricated and singulated in this process were ring-shaped arrays, with inner and outer diameters of 5 mm and 10 mm, respectively. The fabricated CMUT ring arrays demonstrate the ability of this method to successfully and safely singulate the ring arrays and is applicable to any arbitrary 2D shaped MEMS device with uspended microstructures, taking advantage of the inherent planar attributes of DRIE.

  8. Towards a Casimir Force Measurement between Micromachined Parallel Plate Structures

    Directory of Open Access Journals (Sweden)

    Remco J. Wiegerink

    2012-11-01

    Full Text Available Ever since its prediction, experimental investigation of the Casimir force has been of great scientific interest. Many research groups have successfully attempted quantifying the force with different device geometries; however, measurement of the Casimir force between parallel plates with sub-micron separation distance is still a challenging task, since it becomes extremely difficult to maintain sufficient parallelism between the plates. The Casimir force can significantly influence the operation of micro devices and to realize reliable and reproducible devices it is necessary to understand and experimentally verify the influence of the Casimir force at sub-micron scale. In this paper, we present the design principle, fabrication and characterization of micromachined parallel plate structures that could allow the measurement of the Casimir force with tunable separation distance in the range of 100 to 1000 nm. Initially, a gold coated parallel plate structure is explored to measure the Casimir force, but also other material combinations could be investigated. Using gold-silicon eutectic bonding, a reliable approach to bond chips with integrated suspended plates together with a well-defined separation distance in the order of 1–2 μm is developed.

  9. A Micromachined Infrared Senor for an Infrared Focal Plane Array

    Directory of Open Access Journals (Sweden)

    Seong M. Cho

    2008-04-01

    Full Text Available A micromachined infrared sensor for an infrared focal plane array has been designed and fabricated. Amorphous silicon was used as a sensing material, and silicon nitride was used as a membrane material. To get a good absorption in infrared range, the sensor structure was designed as a l/4 cavity structure. A Ni-Cr film was selected as an electrode material and mixed etching scheme was applied in the patterning process of the Ni-Cr electrode. All the processes were made in 0.5 μm iMEMS fabricated in the Electronics and Telecommunication Research Institute (ETRI. The processed MEMS sensor had a small membrane deflection less than 0.15 μm. This small deflection can be attributed to the rigorous balancing of the stresses of individual layers. The efficiency of infrared absorption was more than 75% in the wavelength range of 8 ~ 14 μm. The processed infrared sensor showed high responsivity of ~230 kV/W at 1.0V bias and 2 Hz operation condition. The time constant of the sensor was 8.6 msec, which means that the sensor is suitable to be operated in 30 Hz frame rate.

  10. Review of piezoelectric micromachined ultrasonic transducers and their applications

    International Nuclear Information System (INIS)

    Jung, Joontaek; Lee, Wonjun; Kang, Woojin; Shin, Eunjung; Choi, Hongsoo; Ryu, Jungho

    2017-01-01

    In recent decades, micromachined ultrasonic transducers (MUTs) have been investigated as an alternative to conventional piezocomposite ultrasonic transducers, primarily due to the advantages that microelectromechanical systems provide. Miniaturized ultrasonic systems require ultrasonic transducers integrated with complementary metal-oxide-semiconductor circuits. Hence, piezoelectric MUTs (pMUTs) and capacitive MUTs (cMUTs) have been developed as the most favorable solutions. This paper reviews the basic equations to understand the characteristics of thin-film-based piezoelectric devices and presents recent research on pMUTs, including current approaches and limitations. Methods to improve the coupling coefficient of pMUTs are also investigated, such as device structure, materials, and fabrication techniques. The device structure improvements include multielectrode pMUTs, partially clamped boundary conditions, and 3D pMUTs (curved and domed types), where the latter can provide an electromechanical coupling coefficient of up to 45%. The piezoelectric coefficient ( e 31 ) can be increased by controlling the crystal texture (seed layer of γ -Al 2 O 3 ), using single-crystal (PMN-PT) materials, or control of residual stresses (using SiO 2 layer). Arrays of pMUTs can be implemented for various applications including intravascular ultrasound, fingerprint sensors, rangefinders in air, and wireless power supply systems. pMUTs are expected to be an ideal solution for applications such as mobile biometric security (fingerprint sensors) and rangefinders due to their superior power efficiency and compact size. (topical review)

  11. Design and Simulation of a New Decoupled Micromachined Gyroscope

    Energy Technology Data Exchange (ETDEWEB)

    Sharaf, Abdelhameed [NCRRT, EAEA, 3 Ahmed Elzomer Street, Nasr City, Cairo (Egypt); STRC, AUC, 113 Kasr El Eini Street, 11215, Cairo (Egypt); Sedky, Sherif [STRC, AUC, 113 Kasr El Eini Street, 11215, Cairo (Egypt); Physics Department, AUC, 113 Kasr El Eini Street, 11215, Cairo (Egypt); Habib, S E-D [Electronics and Communication Department, Faculty of Engineering, Cairo University, 12613, Giza (Egypt)

    2006-04-01

    This paper reports on a new decoupled micromachined gyroscope. The proposed sensor is a dual mass type, electrostatically driven to primary mode oscillation and senses, capacitively, the output signal. Full decoupling between drive and sense modes minimizes the mechanical crosstalk. Three different designs are introduced in this work. Drive and sense amplitudes, mechanical and electrical sensitivities, quality factors and approximate bandwidths are extracted analytically and the results are confirmed using finite element analysis. The first design shows drive and sense modes resonance frequencies of 4077 Hz and 4081 Hz respectively; with a frequency mismatch lower than 0.1%. The drive and sense capacitance are 0.213 pF and 0.142 pF respectively. The mechanical and electrical sensitivities are 0.011 {mu}m/ ({sup 0}/s) and 2.75 mV/ ({sup 0}/s) respectively. The third design shows significantly improved mechanical and electrical sensitivities of 0.027 {mu}m/ ({sup 0}/s) and 6.85 mV/ ({sup 0}/s) respectively.

  12. Uneven batch data alignment with application to the control of batch end-product quality.

    Science.gov (United States)

    Wan, Jian; Marjanovic, Ognjen; Lennox, Barry

    2014-03-01

    Batch processes are commonly characterized by uneven trajectories due to the existence of batch-to-batch variations. The batch end-product quality is usually measured at the end of these uneven trajectories. It is necessary to align the time differences for both the measured trajectories and the batch end-product quality in order to implement statistical process monitoring and control schemes. Apart from synchronizing trajectories with variable lengths using an indicator variable or dynamic time warping, this paper proposes a novel approach to align uneven batch data by identifying short-window PCA&PLS models at first and then applying these identified models to extend shorter trajectories and predict future batch end-product quality. Furthermore, uneven batch data can also be aligned to be a specified batch length using moving window estimation. The proposed approach and its application to the control of batch end-product quality are demonstrated with a simulated example of fed-batch fermentation for penicillin production. Copyright © 2013 ISA. Published by Elsevier Ltd. All rights reserved.

  13. Micromachined Millimeter- and Submillimeter-Wave SIS Heterodyne Receivers for Remote Sensing

    Science.gov (United States)

    Hu, Qing

    1998-01-01

    A heterodyne mixer with a micromachined horn antenna and a superconductor -insulator-superconductor (SIS) tunnel junction as mixing element is tested in the W-band (75-115 GHz) frequency range. Micromachined integrated horn antennas consist of a dipole antenna suspended on a thin Si3N4 dielectric membrane inside a pyramidal cavity etched in silicon. The mixer performance is optimized by using a backing plane behind the dipole antenna to tune out the capacitance of the tunnel junction. The lowest receiver noise temperature of 30+/-3 K without any correction) is measured at 106 GHz with a 3-dB bandwidth of 8 GHz. This sensitivity is comparable to the state-of-the-art waveguide and quasi-optical SIS receivers, showing the potential use of micromachined horn antennas in imaging arrays.

  14. A Low-noise Micromachined Millimeter-Wave Heterodyne Mixer using Nb Superconducting Tunnel Junctions

    Science.gov (United States)

    DeLange, Gert; Jacobson, Brian R.; Hu, Qing

    1996-01-01

    A heterodyne mixer with a micromachined horn antenna and a superconductor-insulator-superconductor (SIS) tunnel junction as mixing element is tested in the W-band (75-115 GHz) frequency range. Micromachined integrated horn antennas consist of a dipole antenna suspended on a thin Si3N4 dielectric membrane inside a pyramidal cavity etched in silicon. The mixer performance is optimized by using a backing plane behind the dipole antenna to tune out the capacitance of the tunnel junction. The lowest receiver noise temperature of 30 +/- 3 K (without any correction) is measured at 106 GHz with a 3-dB bandwidth of 8 GHz. This sensitivity is comparable to the state-of-the-art waveguide and quasi-optical SIS receivers, showing the potential use of micromachined horn antennas in imaging arrays.

  15. LSF usage for batch at CERN

    CERN Multimedia

    Schwickerath, Ulrich

    2007-01-01

    Contributed poster to the CHEP07. Original abstract: LSF 7, the latest version of Platform's batch workload management system, addresses many issues which limited the ability of LSF 6.1 to support large scale batch farms, such as the lxbatch service at CERN. In this paper we will present the status of the evaluation and deployment of LSF 7 at CERN, including issues concerning the integration of LSF 7 with the gLite grid middleware suite and, in particular, the steps taken to endure an efficient reporting of the local batch system status and usage to the Grid Information System

  16. Experimental Analysis of Bisbenzocyclobutene Bonded Capacitive Micromachined Ultrasonic Transducers.

    Science.gov (United States)

    Manwar, Rayyan; Chowdhury, Sazzadur

    2016-06-24

    Experimental measurement results of a 1.75 mm × 1.75 mm footprint area Capacitive Micromachined Ultrasonic Transducer (CMUT) planar array fabricated using a bisbenzocyclobutene (BCB)-based adhesive wafer bonding technique has been presented. The array consists of 40 × 40 square diaphragm CMUT cells with a cavity thickness of 900 nm and supported by 10 µm wide dielectric spacers patterned on a thin layer of BCB. A 150 µm wide one µm thick gold strip has been used as the contact pad for gold wire bonding. The measured resonant frequency of 19.3 MHz using a Polytec™ laser Doppler vibrometer (Polytec™ MSA-500) is in excellent agreement with the 3-D FEA simulation result using IntelliSuite™. An Agilent ENA5061B vector network analyzer (VNA) has been used for impedance measurement and the resonance and anti-resonance values from the imaginary impedance curve were used to determine the electromechanical coupling co-efficient. The measured coupling coefficient of 0.294 at 20 V DC bias exhibits 40% higher transduction efficiency as compared to a measured value published elsewhere for a silicon nitride based CMUT. A white light interferometry method was used to measure the diaphragm deflection profiles at different DC bias. The diaphragm center velocity was measured for different sub-resonant frequencies using a Polytec™ laser Doppler vibrometer that confirms vibration of the diaphragm at different excitation frequencies and bias voltages. Transmit and receive operations of CMUT cells were characterized using a pitch-catch method and a -6 dB fractional bandwidth of 23% was extracted from the received signal in frequency domain. From the measurement, it appears that BCB-based CMUTs offer superior transduction efficiency as compared to silicon nitride or silicon dioxide insulator-based CMUTs, and provide a very uniform deflection profile thus making them a suitable candidate to fabricate highly energy efficient CMUTs.

  17. Chemical vapor detection using a capacitive micromachined ultrasonic transducer.

    Science.gov (United States)

    Lee, Hyunjoo J; Park, Kwan Kyu; Kupnik, Mario; Oralkan, O; Khuri-Yakub, Butrus T

    2011-12-15

    Distributed sensing of gas-phase chemicals using highly sensitive and inexpensive sensors is of great interest for many defense and consumer applications. In this paper we present ppb-level detection of dimethyl methylphosphonate (DMMP), a common simulant for sarin gas, with a ppt-level resolution using an improved capacitive micromachined ultrasonic transducer (CMUT) as a resonant chemical sensor. The improved CMUT operates at a higher resonant frequency of 47.7 MHz and offers an improved mass sensitivity of 48.8 zg/Hz/μm(2) by a factor of 2.7 compared to the previous CMUT sensors developed. A low-noise oscillator using the CMUT resonant sensor as the frequency-selective device was developed for real-time sensing, which exhibits an Allan deviation of 1.65 Hz (3σ) in the presence of a gas flow; this translates into a mass resolution of 80.5 zg/μm(2). The CMUT resonant sensor is functionalized with a 50-nm thick DKAP polymer developed at Sandia National Laboratory for dimethyl methylphosphonate (DMMP) detection. To demonstrate ppb-level detection of the improved chemical sensor system, the sensor performance was tested at a certified lab (MIT Lincoln Laboratory), which is equipped with an experimental chemical setup that reliably and accurately delivers a wide range of low concentrations down to 10 ppb. We report a high volume sensitivity of 34.5 ± 0.79 pptv/Hz to DMMP and a good selectivity of the polymer to DMMP with respect to dodecane and 1-octanol.

  18. Multi-objective optimization of glycopeptide antibiotic production in batch and fed batch processes

    DEFF Research Database (Denmark)

    Maiti, Soumen K.; Eliasson Lantz, Anna; Bhushan, Mani

    2011-01-01

    as pareto optimal solutions. These solutions gives flexibility in evaluating the trade-offs and selecting the most suitable operating policy. Here, ε-constraint approach was used to generate the pareto solutions for two objectives: product concentration and product per unit cost of media, for batch and fed...... batch operations using process model for Amycolatopsis balhimycina, a glycopeptide antibiotic producer. This resulted in a set of several pareto optimal solutions with the two objectives ranging from (0.75gl−1, 3.97g$-1) to (0.44gl−1, 5.19g$-1) for batch and from (1.5gl−1, 5.46g$-1) to (1.1gl−1, 6.34g......$-1) for fed batch operations. One pareto solution each for batch and for fed batch mode was experimentally validated....

  19. Fabrication and characterization of a micromachined swirl-shaped ionic polymer metal composite actuator with electrodes exhibiting asymmetric resistance.

    Science.gov (United States)

    Feng, Guo-Hua; Liu, Kim-Min

    2014-05-12

    This paper presents a swirl-shaped microfeatured ionic polymer-metal composite (IPMC) actuator. A novel micromachining process was developed to fabricate an array of IPMC actuators on a glass substrate and to ensure that no shortcircuits occur between the electrodes of the actuator. We demonstrated a microfluidic scheme in which surface tension was used to construct swirl-shaped planar IPMC devices of microfeature size and investigated the flow velocity of Nafion solutions, which formed the backbone polymer of the actuator, within the microchannel. The unique fabrication process yielded top and bottom electrodes that exhibited asymmetric surface resistance. A tool for measuring surface resistance was developed and used to characterize the resistances of the electrodes for the fabricated IPMC device. The actuator, which featured asymmetric electrode resistance, caused a nonzero-bias current when the device was driven using a zero-bias square wave, and we propose a circuit model to describe this phenomenon. Moreover, we discovered and characterized a bending and rotating motion when the IPMC actuator was driven using a square wave. We observed a strain rate of 14.6% and a displacement of 700 μm in the direction perpendicular to the electrode surfaces during 4.5-V actuation.

  20. Long-life micro vacuum chamber for a micromachined cryogenic cooler

    NARCIS (Netherlands)

    Cao, Haishan; Vermeer, Cristian Hendrik; Vanapalli, Srinivas; Holland, Herman J.; ter Brake, Hermanus J.M.

    2015-01-01

    Micromachined cryogenic coolers can be used for cooling small electronic devices to improve their performance. However, for reaching cryogenic temperatures, they require a very good thermal insulation from the warm environment. This is established by a vacuum space that for adequate insulation has

  1. Angular Random Walk Estimation of a Time-Domain Switching Micromachined Gyroscope

    Science.gov (United States)

    2016-10-19

    TECHNICAL DOCUMENT 3308 September 2016 Angular Random Walk Estimation of a Time-Domain Switching Micromachined Gyroscope Andrew B. Sabater Paul...angular random walk (ARW), bias instability, and scale factor instability. While there are methods to address issues with bias and scale factor...8 4. ANGULAR RANDOM WALK CHARACTERIZATION

  2. Sensitivity of Micromachined Joule-Thomson Cooler to Clogging Due to Moisture

    NARCIS (Netherlands)

    Cao, Haishan; Vanapalli, Srinivas; Holland, Herman J.; Vermeer, Cristian Hendrik; ter Brake, Hermanus J.M.

    2015-01-01

    A major issue in long-term operation of micromachined Joule-Thomson coolers is the clogging of the microchannels and/or the restriction due to the deposition of water molecules present in the working fluid. In this study, we present the performance of a microcooler operated with nitrogen gas with

  3. Femtosecond laser micromachining of polylactic acid/graphene composites for designing interdigitated microelectrodes for sensor applications

    Science.gov (United States)

    Paula, Kelly T.; Gaál, Gabriel; Almeida, G. F. B.; Andrade, M. B.; Facure, Murilo H. M.; Correa, Daniel S.; Riul, Antonio; Rodrigues, Varlei; Mendonça, Cleber R.

    2018-05-01

    There is an increasing interest in the last years towards electronic applications of graphene-based materials and devices fabricated from patterning techniques, with the ultimate goal of high performance and temporal resolution. Laser micromachining using femtosecond pulses is an attractive methodology to integrate graphene-based materials into functional devices as it allows changes to the focal volume with a submicrometer spatial resolution due to the efficient nonlinear nature of the absorption, yielding rapid prototyping for innovative applications. We present here the patterning of PLA-graphene films spin-coated on a glass substrate using a fs-laser at moderate pulse energies to fabricate interdigitated electrodes having a minimum spatial resolution of 5 μm. Raman spectroscopy of the PLA-graphene films indicated the presence of multilayered graphene fibers. Subsequently, the PLA-graphene films were micromachined using a femtosecond laser oscillator delivering 50-fs pulses and 800 nm, where the pulse energy and scanning speed was varied in order to determine the optimum irradiation parameters (16 nJ and 100 μm/s) to the fabrication of microstructures. The micromachined patterns were characterized by optical microscopy and submitted to electrical measurements in liquid samples, clearly distinguishing all tastes tested. Our results confirm the femtosecond laser micromachining technique as an interesting approach to efficiently pattern PLA-graphene filaments with high precision and minimal mechanical defects, allowing the easy fabrication of interdigitated structures and an alternative method to those produced by conventional photolithography.

  4. A micromachined silicon valve driven by a miniature bi-stable electro-magnetic actuator

    NARCIS (Netherlands)

    Bohm, S.; Burger, G.J.; Burger, G.J.; Korthorst, M.T.; Roseboom, F.

    2000-01-01

    In this paper a novel combination of a micromachined silicon valve with low dead volume and a bi-stable electromagnetic actuator produced by conventional machining is presented. The silicon valve part, 7×7×1 mm3 in dimensions, is a sandwich construction of two KOH etched silicon wafers with a layer

  5. New technique for fabrication of high frequency piezoelectric Micromachined Ultrasound Transducers

    DEFF Research Database (Denmark)

    Pedersen, T; Thomsen, Erik Vilain; Zawada, T

    2008-01-01

    A novel technique for fabrication of linear arrays of high frequency piezoelectric Micromachined Ultrasound Transducers (pMUT) on silicon substrates is presented. Piezoelectric elements are formed by deposition of PZT ((PbZrxTi1-x)O3) into etched features of the silicon substrate...

  6. Unique Femtosecond Micromachining Methods in Semi-Insulating and Conducting Silicon Carbide (Preprint)

    National Research Council Canada - National Science Library

    Brewer, Chris; Dorsey, Don; Campbell, Angela; Juhl, Shane; DesAutels, G. L; Finet, Marc; Ristich, Scott; Whitaker, Matt; Powers, Peter E; Zhan, Qiwen

    2007-01-01

    ...); a wide bandgap semiconductor material provided by Wright-Patterson AFB AFRL/MLPS. Gratings were micro-machined into these materials using a novel anamorphic lens design and an automated x, y, z linear stage to control the sample position...

  7. Separation and Detection of Toxic Gases with a Silicon Micromachined Gas Chromatography System

    Science.gov (United States)

    Kolesar, Edward S.; Reston, Rocky R.

    1995-01-01

    A miniature gas chromatography (GC) system was designed and fabricated using silicon micromachining and integrated circuit (IC) processing techniques. The silicon micromachined gas chromatography system (SMGCS) is composed of a miniature sample injector that incorporates a 10 microliter sample loop; a 0.9 meter long, rectangular shaped (300 micrometer width and 10 micrometer height) capillary column coated with a 0.2 micrometer thick copper phthalocyanine (CuPc) stationary phase; and a dual detector scheme based upon a CuPc-coated chemiresistor and a commercially available 125 micrometer diameter thermal conductivity detector (TCD) bead. Silicon micromachining was employed to fabricate the interface between the sample injector and the GC column, the column itself, and the dual detector cavity. A novel IC thin-film processing technique was developed to sublime the CuPc stationary phase coating on the column walls that were micromachined in the host silicon wafer substrate and Pyrex (r) cover plate, which were then electrostatically bonded together. The SMGCS can separate binary gas mixtures composed of parts-per-million (ppm) concentrations of ammonia (NH3) and nitrogen dioxide (NO2) when isothermally operated (55-80 degrees C). With a helium carrier gas and nitrogen diluent, a 10 microliter sample volume containing ammonia and nitrogen dioxide injected at 40 psi ((2.8 x 10(exp 5)Pa)) can be separated in less than 30 minutes.

  8. 40 CFR 63.1321 - Batch process vents provisions.

    Science.gov (United States)

    2010-07-01

    ... the reference control technology requirements for Group 1 batch process vents in § 63.1322, the.... Owners or operators of all Group 2 batch process vents shall comply with the applicable reference control....1323 is not required. (2) For batch process vents and aggregate batch vent streams, the control...

  9. Ethanol effect on batch and fed-batch Arthrospira platensis growth.

    Science.gov (United States)

    Bezerra, Raquel P; Matsudo, Marcelo C; Pérez Mora, Lina S; Sato, Sunao; de Carvalho, João C Monteiro

    2014-04-01

    The ability of Arthrospira platensis to use ethanol as a carbon and energy source was investigated by batch process and fed-batch process. A. platensis was cultivated under the effect of a single addition (batch process) and a daily pulse feeding (fed-batch process) of pure ethanol, at different concentrations, to evaluate cell concentration (X) and specific growth rate (μ). A marked increase was observed in the cell concentration of A. platensis in runs with ethanol addition when compared to control cultures without ethanol addition. The fed-batch process using an ethanol concentration of 38 mg L(-1) days(-1) reached the maximum cell concentration of 2,393 ± 241 mg L(-1), about 1.5-fold that obtained in the control culture. In all experiments, the maximum specific growth rate was observed in the early exponential phase of cell growth. In the fed-batch process, μ decreased more slowly than in the batch process and control culture, resulting in the highest final cell concentration. Ethanol can be used as a feasible carbon and energy source for A. platensis growth via a fed-batch process.

  10. Energy efficiency of batch and semi-batch (CCRO) reverse osmosis desalination.

    Science.gov (United States)

    Warsinger, David M; Tow, Emily W; Nayar, Kishor G; Maswadeh, Laith A; Lienhard V, John H

    2016-12-01

    As reverse osmosis (RO) desalination capacity increases worldwide, the need to reduce its specific energy consumption becomes more urgent. In addition to the incremental changes attainable with improved components such as membranes and pumps, more significant reduction of energy consumption can be achieved through time-varying RO processes including semi-batch processes such as closed-circuit reverse osmosis (CCRO) and fully-batch processes that have not yet been commercialized or modelled in detail. In this study, numerical models of the energy consumption of batch RO (BRO), CCRO, and the standard continuous RO process are detailed. Two new energy-efficient configurations of batch RO are analyzed. Batch systems use significantly less energy than continuous RO over a wide range of recovery ratios and source water salinities. Relative to continuous RO, models predict that CCRO and batch RO demonstrate up to 37% and 64% energy savings, respectively, for brackish water desalination at high water recovery. For batch RO and CCRO, the primary reductions in energy use stem from atmospheric pressure brine discharge and reduced streamwise variation in driving pressure. Fully-batch systems further reduce energy consumption by not mixing streams of different concentrations, which CCRO does. These results demonstrate that time-varying processes can significantly raise RO energy efficiency. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Model Penjadwalan Batch Multi Item dengan Dependent Processing Time

    Directory of Open Access Journals (Sweden)

    Sukoyo Sukoyo

    2010-01-01

    Full Text Available This paper investigates a development of single machine batch scheduling for multi items with dependent processing time. The batch scheduling problem is to determine simultaneously number of batch (N, which item and its size allocated for each batch, and processing sequences of resulting batches. We use total actual flow time as the objective of schedule performance. The multi item batch scheduling problem could be formulated into a biner-integer nonlinear programming model because the number of batch should be in integer value, the allocation of items to resulting batch need binary values, and also there are some non-linearity on objective function and constraint due to the dependent processing time. By applying relaxation on the decision variable of number of batch (N as parameter, a heuristic procedure could be applied to find solution of the single machine batch scheduling problem for multi items.

  12. Fly's proprioception-inspired micromachined strain-sensing structure: idea, design, modeling and simulation, and comparison with experimental results

    Energy Technology Data Exchange (ETDEWEB)

    Wicaksono, D H B [Department of Microelectronics, Delft University of Technology, Mekelweg 4, Delft, Zuid-Holland 2628CD (Netherlands); Zhang, L-J [Department of Microelectronics, Delft University of Technology, Mekelweg 4, Delft, Zuid-Holland 2628CD (Netherlands); Pandraud, G [Department of Microelectronics, Delft University of Technology, Mekelweg 4, Delft, Zuid-Holland 2628CD (Netherlands); French, P J [Department of Microelectronics, Delft University of Technology, Mekelweg 4, Delft, Zuid-Holland 2628CD (Netherlands); Vincent, J F V [Department of Mech. Engineering, Bath University Bath, BA2 7AY (United Kingdom)

    2006-04-01

    A new strain-sensing structure inspired from insect's (especially the Fly) propricoception sensor is devised. The campaniform sensillum is a strain-sensing microstructure with very high sensitivity despite its small dimension (diameter {approx}10 {mu}m in a relatively stiff material of insect's exocuticle (E = {approx}10{sup 9} Pa). Previous work shows that the high sensitivity of this structure towards strain is due to its membrane-in-recess- and strainconcentrating-hole-features. Based on this inspiration, we built similar structure using silicon micromachining technology. Then a simple characterisation setup was devised. Here, we present briefly, finite-element modeling and simulation based on this actual sample preparation for the characterisation. As comparison and also to understand mechanical features responsible for the strain-sensitivity, we performed the modeling on different mechanical structures: bulk chunk, blind-hole, through-hole, surface membrane, and membrane-in-recess. The actual experimental characterisation was performed previously using optical technique to membrane in-recess micromachined Si structure. The FEM simulation results confirm that the bending stress and strain are concentrated in the hole-vicinity. The membrane inside the hole acts as displacement transducer. The FEM is in conformity with previous analytical results, as well as the optical characterisation result. The end goal is to build a new type MEMS strain sensor.

  13. Water quality - Evaluation of the aerobic biodegradability of organic compounds at low concentrations. Part 1: Shake-flask batch test with surface water or suface water/sediment suspensions. ISO 14592-1

    DEFF Research Database (Denmark)

    Nyholm, Niels; Pagga, U.

    environment (pelagic test) or to surface water with suspended solids or sediments added to obtain a level of 0,1 g/l to 1 g/l dry mass (suspended sediment test) to simulate a water-to-sediment interface or a water body with resuspended sediment material. ISO 14592-1:2002 is applicable to organic test......-growth kinetics). This test method is not recommended for use as proof of ultimate biodegradation which is better assessed using other standardized tests. It is also not applicable to studies on metabolite formation and accumulation which require higher test concentrations....

  14. Systematic Methodology for Reproducible Optimizing Batch Operation

    DEFF Research Database (Denmark)

    Bonné, Dennis; Jørgensen, Sten Bay

    2006-01-01

    contribution furthermore presents how the asymptotic convergence of Iterative Learning Control is combined with the closed-loop performance of Model Predictive Control to form a robust and asymptotically stable optimal controller for ensuring reliable and reproducible operation of batch processes....... This controller may also be used for Optimizing control. The modeling and control performance is demonstrated on a fed-batch protein cultivation example. The presented methodologies lend themselves directly for application as Process Analytical Technologies (PAT).......This contribution presents a systematic methodology for rapid acquirement of discrete-time state space model representations of batch processes based on their historical operation data. These state space models are parsimoniously parameterized as a set of local, interdependent models. The present...

  15. Fuzzy batch controller for granular materials

    Directory of Open Access Journals (Sweden)

    Zamyatin Nikolaj

    2018-01-01

    Full Text Available The paper focuses on batch control of granular materials in production of building materials from fluorine anhydrite. Batching equipment is intended for smooth operation and timely feeding of supply hoppers at a required level. Level sensors and a controller of an asynchronous screw drive motor are used to control filling of the hopper with industrial anhydrite binders. The controller generates a required frequency and ensures required productivity of a feed conveyor. Mamdani-type fuzzy inference is proposed for controlling the speed of the screw that feeds mixture components. As related to production of building materials based on fluoride anhydrite, this method is used for the first time. A fuzzy controller is proven to be effective in controlling the filling level of the supply hopper. In addition, the authors determined optimal parameters of the batching process to ensure smooth operation and production of fluorine anhydrite materials of specified properties that can compete with gypsum-based products.

  16. Control of Batch Processes Based on Hierarchical Petri Nets

    OpenAIRE

    YAJIMA, Tomoyuki; ITO, Takashi; HASHIZUME, Susumu; KURIMOTO, Hidekazu; ONOGI, Katsuaki

    2004-01-01

    A batch process is a typical concurrent system in which multiple interacting tasks are carried out in parallel on several batches at the same time. A major difficulty in designing a batch control system is the lack of modeling techniques. This paper aims at developing a method of constructing batch control system models in a hierarchical manner and operating batch processes using the constructed models. For this purpose, it first defines process and plant specifications described by partial l...

  17. Monitoring of batch processes using spectroscopy

    NARCIS (Netherlands)

    Gurden, S. P.; Westerhuis, J. A.; Smilde, A. K.

    2002-01-01

    There is an increasing need for new techniques for the understanding, monitoring and the control of batch processes. Spectroscopy is now becoming established as a means of obtaining real-time, high-quality chemical information at frequent time intervals and across a wide range of industrial

  18. Exploring the Transition From Batch to Online

    DEFF Research Database (Denmark)

    Jørgensen, Anker Helms

    2010-01-01

    The transition from using computers in batch mode with punch cards, paper tape, piles of print, and lengthy response times to online mode by way of the video display terminal took place in most organizations in the 1970s and 1980s. The video display terminal was a significant forerunner...

  19. Fabrication of Super Hydrophobic Surfaces by fs Laser Pulses : How to Produce Self-Cleaning Surfaces

    NARCIS (Netherlands)

    Groenendijk, M.N.W.

    2008-01-01

    The chair of Applied Laser Technology of the University of Twente, The Netherlands, is performing research into applications of ultrashort pulsed lasers for micromachining. In a recent project, PhD student Max Groenendijk developed a method for the production of super water repellant surfaces by

  20. Design and Fabrication of Micromachined Absolute Micro Pressure Sensor

    Directory of Open Access Journals (Sweden)

    P. A. Alvi

    2008-09-01

    Full Text Available Absolute micro pressure sensors have been designed and fabricated in batches, which will be capable to give output responses in form of voltage signal as a function of pressure. The piezoresistive effect has been chosen for this device because it provides an observable resistance changes that is a linear function of pressure and is observable at low stress levels. A membrane is used as a stress-magnifying device. The pressure-induced stresses in the membrane are sensed by properly oriented piezoresistors interconnected to form a bridge. For the purpose of pressure sensing, boron doped polysilicon piezoresistors have been fabricated in half Wheatstone bridge configuration. A 100 µm sized square membrane, over which polysilicon resistors are deposited, has been realized having thickness of 0.8 µm with the help of a sacrificial layer of LPCVD polysilicon thin film. Highly selective anisotropic etching of silicon has been performed in 45 % wt KOH at 75 oC for conical cavity formation under the membrane. The developed fabrication process is competent to provide nearly 1089 chips of 1 mm x 1 mm size on a two-inch diameter silicon (100 wafer.

  1. In-plane diffraction loss free optical cavity using coated optical fiber and silicon micromachined spherical mirror

    Science.gov (United States)

    Sabry, Yasser; Bourouina, Tarik; Saadany, Bassam; Khalil, Diaa

    2013-03-01

    Light trapping in optical cavities has many applications in optical telecommunications, biomedical optics, atomic studies, and chemical analysis. Efficient optical coupling in these cavities is an important engineering problem that affects greatly the cavity performance. One interesting way to form an optical cavity, while simultaneously connected to the rest of the optical systems, is to use an optical fiber surface as one of the cavity mirrors while the second mirror is fabricated by MEMS technology. In this way, cavity tuning with a MEMS actuator is a simple achievable task with low cost in mass production. The main problem in this solution is the high diffraction loss associated with the small spot size at the output of the standard single-mode fiber (SMF). Diffraction loss in the cavity is usually overcome by using an expensive lensed fiber or by inserting a coated lens in the cavity leading to a long cavity with small free spectral range (FSR). In this work, we report a Fabry-Perot cavity formed by a multilayer-coated cleaved-surface SMF inserted into a grove while facing a spherical micromirror; both are fabricated by silicon micromachining. The light is trapped inside the cavity while propagating in-plane of the wafer substrate. The light is injected in and collected from a Corning SMF-28 optical fiber with a coated surface reflectivity of about 98% at 1330 nm (O-band). The silicon mirror surface is aluminum metalized with a reflectivity of about 92%. The measured cavity has a line width of 0.45 nm around 1330 nm with a FSR of 26 nm. The obtained results indicate an almost diffraction-loss free optical cavity with a quality factor close to 3000, limited by the optical surfaces reflectivity that can be improved in future by an optimized mirror fabrication process and better matching of the fiber multilayer coating.

  2. Optimized design of micromachined electric field mills to maximize electrostatic field sensitivity

    Directory of Open Access Journals (Sweden)

    Yu Zhou

    2016-07-01

    Full Text Available This paper describes the design optimization of a micromachined electric field mill, in relation to maximizing its output signal. The cases studied are for a perforated electrically grounded shutter vibrating laterally over sensing electrodes. It is shown that when modeling the output signal of the sensor, the differential charge on the sense electrodes when exposed to vs. visibly shielded from the incident electric field must be considered. Parametric studies of device dimensions show that the shutter thickness and its spacing from the underlying electrodes should be minimized as these parameters very strongly affect the MEFM signal. Exploration of the shutter perforation size and sense electrode width indicate that the best MEFM design is one where shutter perforation widths are a few times larger than the sense electrode widths. Keywords: MEFM, Finite element method, Electric field measurement, MEMS, Micromachining

  3. Laser direct micro-machining with top-hat-converted single mode lasers

    Science.gov (United States)

    Homburg, O.; Toennissen, F.; Mitra, T.; Lissotschenko, V.

    2008-02-01

    Laser direct micro-machining processes are used in a variety of industries like inkjet printing, semiconductor processing, solar technology, flat-panel display production and medicine. Various kinds of materials, e.g. ceramics, metals, isolators, oxides, organics and semiconductors are being structured. In most cases pulsed single mode solid state lasers with an inhomogeneous Gaussian beam profile are employed, like YAG lasers and their harmonics. However, the quality and functionality of the generated structures and micro-systems as well as the speed of the process can be improved by the utilization of homogeneous top hat profiles. The beam shaping principle of refractive Gaussian-to-top-hat converters is shown. Compact beam shaper modules based on this principle have been developed - supporting most direct laser micro-machining applications. The resulting process advantages are demonstrated by selected application results, namely the drilling of holes and patterning of trenches for different kinds of materials.

  4. Monte Carlo simulation on kinetics of batch and semi-batch free radical polymerization

    KAUST Repository

    Shao, Jing

    2015-10-27

    Based on Monte Carlo simulation technology, we proposed a hybrid routine which combines reaction mechanism together with coarse-grained molecular simulation to study the kinetics of free radical polymerization. By comparing with previous experimental and simulation studies, we showed the capability of our Monte Carlo scheme on representing polymerization kinetics in batch and semi-batch processes. Various kinetics information, such as instant monomer conversion, molecular weight, and polydispersity etc. are readily calculated from Monte Carlo simulation. The kinetic constants such as polymerization rate k p is determined in the simulation without of “steady-state” hypothesis. We explored the mechanism for the variation of polymerization kinetics those observed in previous studies, as well as polymerization-induced phase separation. Our Monte Carlo simulation scheme is versatile on studying polymerization kinetics in batch and semi-batch processes.

  5. Femtosecond laser micro-machined polyimide films for cell scaffold applications.

    Science.gov (United States)

    Antanavičiūtė, Ieva; Šimatonis, Linas; Ulčinas, Orestas; Gadeikytė, Aušra; Abakevičienė, Brigita; Tamulevičius, Sigitas; Mikalayeva, Valeryia; Skeberdis, Vytenis Arvydas; Stankevičius, Edgaras; Tamulevičius, Tomas

    2018-02-01

    Engineering of sophisticated synthetic 3D scaffolds that allow controlling behaviour and location of the cells requires advanced micro/nano-fabrication techniques. Ultrafast laser micro-machining employing a 1030-nm wavelength Yb:KGW femtosecond laser and a micro-fabrication workstation for micro-machining of commercially available 12.7 and 25.4 μm thickness polyimide (PI) film was applied. Mechanical properties of the fabricated scaffolds, i.e. arrays of differently spaced holes, were examined via custom-built uniaxial micro-tensile testing and finite element method simulations. We demonstrate that experimental micro-tensile testing results could be numerically simulated and explained by two-material model, assuming that 2-6 μm width rings around the holes possessed up to five times higher Young's modulus and yield stress compared with the rest of the laser intacted PI film areas of 'dog-bone'-shaped specimens. That was attributed to material modification around the micro-machined holes in the vicinity of the position of the focused laser beam track during trepanning drilling. We demonstrate that virgin PI films provide a suitable environment for the mobility, proliferation and intercellular communication of human bone marrow mesenchymal stem cells, and discuss how cell behaviour varies on the micro-machined PI films with holes of different diameters (3.1, 8.4 and 16.7 μm) and hole spacing (30, 35, 40 and 45 μm). We conclude that the holes of 3.1 μm diameter were sufficient for metabolic and genetic communication through membranous tunneling tubes between cells residing on the opposite sides of PI film, but prevented the trans-migration of cells through the holes. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  6. Optimized design of micromachined electric field mills to maximize electrostatic field sensitivity

    OpenAIRE

    Zhou, Yu; Shafai, Cyrus

    2016-01-01

    This paper describes the design optimization of a micromachined electric field mill, in relation to maximizing its output signal. The cases studied are for a perforated electrically grounded shutter vibrating laterally over sensing electrodes. It is shown that when modeling the output signal of the sensor, the differential charge on the sense electrodes when exposed to vs. visibly shielded from the incident electric field must be considered. Parametric studies of device dimensions show that t...

  7. Batch and fed-batch production of butyric acid by Clostridium butyricum ZJUCB

    Science.gov (United States)

    He, Guo-qing; Kong, Qing; Chen, Qi-he; Ruan, Hui

    2005-01-01

    The production of butyric acid by Clostridium butyricum ZJUCB at various pH values was investigated. In order to study the effect of pH on cell growth, butyric acid biosynthesis and reducing sugar consumption, different cultivation pH values ranging from 6.0 to 7.5 were evaluated in 5-L bioreactor. In controlled pH batch fermentation, the optimum pH for cell growth and butyric acid production was 6.5 with a cell yield of 3.65 g/L and butyric acid yield of 12.25 g/L. Based on these results, this study then compared batch and fed-batch fermentation of butyric acid production at pH 6.5. Maximum value (16.74 g/L) of butyric acid concentration was obtained in fed-batch fermentation compared to 12.25 g/L in batch fermentation. It was concluded that cultivation under fed-batch fermentation mode could enhance butyric acid production significantly (P<0.01) by C. butyricum ZJUCB. PMID:16252341

  8. TOPICAL REVIEW: Capacitive micromachined ultrasonic transducer arrays for minimally invasive medical ultrasound

    Science.gov (United States)

    Chen, Jingkuang

    2010-02-01

    This paper reviews the minimally invasive capacitive micromachined ultrasonic transducer (CMUT) arrays for medical diagnosis and therapy. While piezoelectric transducers dominate today's medical ultrasound market, the capacitive micromachined ultrasonic transducer has recently emerged as a promising alternative which delivers a comparable device performance to its piezoelectric counterparts, is compatible with front-end circuit integration, allows high-density imager integration and is relative easy in miniaturization. Utilizing MEMS technology, the substrate of CMUT arrays can be micromachined into miniature platforms with various geometrical shapes, which include needles, three-dimensional prisms, as well as other flexible-substrate configurations. These arrays are useful for reaching deep inside the tissue or an organ with a minimally invasive approach. Due to the close proximity of the transducers to the target organ/tissue, a higher resolution/accuracy of diagnostic information can be achieved. In addition to pulse-echo and photoacoustic imaging, high-power CMUT devices capable of delivering ultrasounds with a pressure greater than 1.0 MPa have been monolithically integrated with imager CMUTs for image-guided therapy (IGT). Such miniature devices would facilitate diagnostic and therapy interventions not possible with conventional piezoelectric transducers.

  9. Modeling and Experimental Study on Characterization of Micromachined Thermal Gas Inertial Sensors

    Directory of Open Access Journals (Sweden)

    Yan Su

    2010-09-01

    Full Text Available Micromachined thermal gas inertial sensors based on heat convection are novel devices that compared with conventional micromachined inertial sensors offer the advantages of simple structures, easy fabrication, high shock resistance and good reliability by virtue of using a gaseous medium instead of a mechanical proof mass as key moving and sensing elements. This paper presents an analytical modeling for a micromachined thermal gas gyroscope integrated with signal conditioning. A simplified spring-damping model is utilized to characterize the behavior of the sensor. The model relies on the use of the fluid mechanics and heat transfer fundamentals and is validated using experimental data obtained from a test-device and simulation. Furthermore, the nonideal issues of the sensor are addressed from both the theoretical and experimental points of view. The nonlinear behavior demonstrated in experimental measurements is analyzed based on the model. It is concluded that the sources of nonlinearity are mainly attributable to the variable stiffness of the sensor system and the structural asymmetry due to nonideal fabrication.

  10. A cellular-automata and particle-tracking simulation of abrasive jet micromachining of polymethyl-methacrylate

    International Nuclear Information System (INIS)

    Ciampini, D; Papini, M

    2011-01-01

    A cellular automaton simulation which is able to predict the geometry of micro-features etched into ductile erosive targets, as a result of abrasive jet micromachining (AJM), is presented. Similar to a previous simulation for the AJM of brittle erosive targets, the movement of individual erodent particles is tracked in a simulated environment, including their collisions with, and ricochet from, the mask and target substrate modeled as cellular-automatons. A new cell erosion algorithm is presented in order to allow the previous simulation to be applied to the AJM of ductile materials. A previously published empirical erosion rule, which related the erosion rate of ductile substrates caused by a jet, was also proven to be applicable, to a good approximation, to single particle impacts. With this new cell erosion algorithm, the predictions of the model compared well with measurements of the surface evolution of unmasked channels, masked micro-holes and micro-channels machined in polymethyl-methacrylate. The results also highlight the importance of modeling the effect of particle size on the prediction of the size and shape of features fabricated in ductile erosive materials using AJM

  11. BATCHING PRINCIPLE OF RATING POINT ACCRUAL

    Directory of Open Access Journals (Sweden)

    S. A. Safontsev

    2014-01-01

    Full Text Available The paper analyzes characteristics of the postindustrial educational system, including the credit competence assessment, academic loads, and module-rating discipline structure. The employers’ judgments, reflected in the survey outcomes, make it possible to single out the most significant competencies for students to master. Such findings are regarded as a foundation for developing the assignment modules, integrating the problematic, testing and projecting tasks, designed to master necessary competences; their effectiveness is estimated by using the criteria of behavioral psychology. The paper demonstrates the sequences of monitoring assessment of students’ academic achievements, and recommends the batching principle of rating point accrual, based on criterion-oriented evaluation standards, reflecting students’ competence levels. The authors identify the basic competence indicators: interest in the subject, reflections on the test results, and inner motivation for project activities. The complex of batching equations is given for developing the training cards of academic disciplines, and guaranteeing the effectiveness of education system.

  12. Optimal operation of batch membrane processes

    CERN Document Server

    Paulen, Radoslav

    2016-01-01

    This study concentrates on a general optimization of a particular class of membrane separation processes: those involving batch diafiltration. Existing practices are explained and operational improvements based on optimal control theory are suggested. The first part of the book introduces the theory of membrane processes, optimal control and dynamic optimization. Separation problems are defined and mathematical models of batch membrane processes derived. The control theory focuses on problems of dynamic optimization from a chemical-engineering point of view. Analytical and numerical methods that can be exploited to treat problems of optimal control for membrane processes are described. The second part of the text builds on this theoretical basis to establish solutions for membrane models of increasing complexity. Each chapter starts with a derivation of optimal operation and continues with case studies exemplifying various aspects of the control problems under consideration. The authors work their way from th...

  13. UPTAKE OF HEAVY METALS IN BATCH SYSTEMS BY A RECYCLED IRON-BEARING MATERIAL

    Science.gov (United States)

    An iron-bearing material deriving from surface finishing operations in the manufacturing of cast-iron components demonstrates potential for removal of heavy metals from aqueous waste streams. Batch isotherm and rate experiments were conducted for uptake of cadmium, zinc, and lead...

  14. Batch calculations in CalcHEP

    International Nuclear Information System (INIS)

    Pukhov, A.

    2003-01-01

    CalcHEP is a clone of the CompHEP project which is developed by the author outside of the CompHEP group. CompHEP/CalcHEP are packages for automatic calculations of elementary particle decay and collision properties in the lowest order of perturbation theory. The main idea prescribed into the packages is to make available passing on from the Lagrangian to the final distributions effectively with a high level of automation. According to this, the packages were created as a menu driven user friendly programs for calculations in the interactive mode. From the other side, long-time calculations should be done in the non-interactive regime. Thus, from the beginning CompHEP has a problem of batch calculations. In CompHEP 33.23 the batch session was realized by mean of interactive menu which allows to the user to formulate the task for batch. After that the not-interactive session was launched. This way is too restricted, not flexible, and leads to doubling in programming. In this article I discuss another approach how one can force an interactive program to work in non-interactive mode. This approach was realized in CalcHEP 2.1 disposed on http://theory.sinp.msu.ru/~pukhov/calchep.html

  15. Pollution prevention applications in batch manufacturing operations

    Science.gov (United States)

    Sykes, Derek W.; O'Shaughnessy, James

    2004-02-01

    Older, "low-tech" batch manufacturing operations are often fertile grounds for gains resulting from pollution prevention techniques. This paper presents a pollution prevention technique utilized for wastewater discharge permit compliance purposes at a batch manufacturer of detergents, deodorants, and floor-care products. This manufacturer generated industrial wastewater as a result of equipment rinses required after each product batch changeover. After investing a significant amount of capital on end of pip-line wastewater treatment technology designed to address existing discharge limits, this manufacturer chose to investigate alternate, low-cost approaches to address anticipated new permit limits. Mass balances using spreadsheets and readily available formulation and production data were conducted on over 300 products to determine how each individual product contributed to the total wastewater pollutant load. These mass balances indicated that 22 products accounted for over 55% of the wastewater pollutant. Laboratory tests were conducted to determine whether these same products could accept their individual changeover rinse water as make-up water in formulations without sacrificing product quality. This changeover reuse technique was then implement at the plant scale for selected products. Significant reductions in wastewater volume (25%) and wastewater pollutant loading (85+%) were realized as a direct result of this approach.

  16. Batch-batch stable microbial community in the traditional fermentation process of huyumei broad bean pastes.

    Science.gov (United States)

    Zhu, Linjiang; Fan, Zihao; Kuai, Hui; Li, Qi

    2017-09-01

    During natural fermentation processes, a characteristic microbial community structure (MCS) is naturally formed, and it is interesting to know about its batch-batch stability. This issue was explored in a traditional semi-solid-state fermentation process of huyumei, a Chinese broad bean paste product. The results showed that this MCS mainly contained four aerobic Bacillus species (8 log CFU per g), including B. subtilis, B. amyloliquefaciens, B. methylotrophicus, and B. tequilensis, and the facultative anaerobe B. cereus with a low concentration (4 log CFU per g), besides a very small amount of the yeast Zygosaccharomyces rouxii (2 log CFU per g). The dynamic change of the MCS in the brine fermentation process showed that the abundance of dominant species varied within a small range, and in the beginning of process the growth of lactic acid bacteria was inhibited and Staphylococcus spp. lost its viability. Also, the MCS and its dynamic change were proved to be highly reproducible among seven batches of fermentation. Therefore, the MCS naturally and stably forms between different batches of the traditional semi-solid-state fermentation of huyumei. Revealing microbial community structure and its batch-batch stability is helpful for understanding the mechanisms of community formation and flavour production in a traditional fermentation. This issue in a traditional semi-solid-state fermentation of huyumei broad bean paste was firstly explored. This fermentation process was revealed to be dominated by a high concentration of four aerobic species of Bacillus, a low concentration of B. cereus and a small amount of Zygosaccharomyces rouxii. Lactic acid bacteria and Staphylococcus spp. lost its viability at the beginning of fermentation. Such the community structure was proved to be highly reproducible among seven batches. © 2017 The Society for Applied Microbiology.

  17. 40 CFR 63.1408 - Aggregate batch vent stream provisions.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 11 2010-07-01 2010-07-01 true Aggregate batch vent stream provisions... § 63.1408 Aggregate batch vent stream provisions. (a) Emission standards. Owners or operators of aggregate batch vent streams at a new or existing affected source shall comply with either paragraph (a)(1...

  18. 7 CFR 58.728 - Cooking the batch.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Cooking the batch. 58.728 Section 58.728 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Standards... Procedures § 58.728 Cooking the batch. Each batch of cheese within the cooker, including the optional...

  19. Semiautomated, Reproducible Batch Processing of Soy

    Science.gov (United States)

    Thoerne, Mary; Byford, Ivan W.; Chastain, Jack W.; Swango, Beverly E.

    2005-01-01

    A computer-controlled apparatus processes batches of soybeans into one or more of a variety of food products, under conditions that can be chosen by the user and reproduced from batch to batch. Examples of products include soy milk, tofu, okara (an insoluble protein and fiber byproduct of soy milk), and whey. Most processing steps take place without intervention by the user. This apparatus was developed for use in research on processing of soy. It is also a prototype of other soy-processing apparatuses for research, industrial, and home use. Prior soy-processing equipment includes household devices that automatically produce soy milk but do not automatically produce tofu. The designs of prior soy-processing equipment require users to manually transfer intermediate solid soy products and to press them manually and, hence, under conditions that are not consistent from batch to batch. Prior designs do not afford choices of processing conditions: Users cannot use previously developed soy-processing equipment to investigate the effects of variations of techniques used to produce soy milk (e.g., cold grinding, hot grinding, and pre-cook blanching) and of such process parameters as cooking times and temperatures, grinding times, soaking times and temperatures, rinsing conditions, and sizes of particles generated by grinding. In contrast, the present apparatus is amenable to such investigations. The apparatus (see figure) includes a processing tank and a jacketed holding or coagulation tank. The processing tank can be capped by either of two different heads and can contain either of two different insertable mesh baskets. The first head includes a grinding blade and heating elements. The second head includes an automated press piston. One mesh basket, designated the okara basket, has oblong holes with a size equivalent to about 40 mesh [40 openings per inch (.16 openings per centimeter)]. The second mesh basket, designated the tofu basket, has holes of 70 mesh [70 openings

  20. Bagasse hydrolyzates from Agave tequilana as substrates for succinic acid production by Actinobacillus succinogenes in batch and repeated batch reactor.

    Science.gov (United States)

    Corona-González, Rosa Isela; Varela-Almanza, Karla María; Arriola-Guevara, Enrique; Martínez-Gómez, Álvaro de Jesús; Pelayo-Ortiz, Carlos; Toriz, Guillermo

    2016-04-01

    The aim of this work was to obtain fermentable sugars by enzymatic or acid hydrolyses of Agave tequilana Weber bagasse in order to produce succinic acid with Actinobacillus succinogenes. Hydrolyses were carried out with mineral acids (sulfuric and hydrochloric acids) or a commercial cellulolytic enzyme, and were optimized statistically by a response surface methodology, having as factors the concentration of acid/enzyme and time of hydrolysis. The concentration of sugars obtained at optimal conditions for each hydrolysis were 21.7, 22.4y 19.8g/L for H2SO4, HCl and the enzymatic preparation respectively. Concerning succinic acid production, the enzymatic hydrolyzates resulted in the highest yield (0.446g/g) and productivity (0.57g/Lh) using A. succinogenes in a batch reactor system. Repeated batch fermentation with immobilized A. succinogenes in agar and with the enzymatic hydrolyzates resulted in a maximum concentration of succinic acid of 33.6g/L from 87.2g/L monosaccharides after 5 cycles in 40h, obtaining a productivity of 1.32g/Lh. Copyright © 2016. Published by Elsevier Ltd.

  1. Operation parameters of a small scale batch distillation column for hydrous ethanol fuel (HEF production

    Directory of Open Access Journals (Sweden)

    Edson Luiz Foletto

    2015-01-01

    Full Text Available Batch distillation applied to hydrous ethanol fuel (HEF production on a small scale still requires operating conditions that ensure optimal top product quality and productivity. The aim of this study is to statistically validate a batch still through the employment of response surface methodology (RSM. Operational and productivity parameters were formulated in order to guarantee quality compliance with the legal requirements for the top product concentration, besides providing support information to control the production of HEF on a small scale. The reboiler control and dephlegmator temperatures maintained within the range of 97.5 to 99.5°C and 60 to 70°C, respectively, combined with a variable reflux ratio, was satisfactory in obtaining a top product concentration, in accordance with legal regulations, as well as high productivity. The results of this study may contribute to the assembly of a simple and low-cost batch distillation control system.

  2. Design and Construction of a Batch Oven for Investigation of Industrial Continuous

    DEFF Research Database (Denmark)

    Stenby, Mette; Nielsen, Brian; Risum, Jørgen

    2011-01-01

    A new batch oven has been designed and build to model baking processes as seen in large scale tunnel ovens. In order to simulate the conditions found in tunnel ovens a number of critical parameters are controllable: The temperature, the humidity and the air velocity. The band movement is simulated...... by moving the two air ducts above and below the products; in this way it is possible to keep the baking tray steady for continuous measurements of the product weight. During baking the shape and colour of the product can be monitored visually through a window. The simultaneous measuring of mass and visual...... aspects is a unique feature of this batch oven. Initial experiments of reproducing tunnel oven baking in the batch oven have shown good results, based on comparisons of weight loss, dry matter content and surface colour. The measured quality parameters did not differ significantly. Even though a few...

  3. CONVERSION OF PINEAPPLE JUICE WASTE INTO LACTIC ACID IN BATCH AND FED – BATCH FERMENTATION SYSTEMS

    Directory of Open Access Journals (Sweden)

    Abdullah Mochamad Busairi

    2012-01-01

    Full Text Available Pineapple juice waste contains valuable components, which are mainly sucrose, glucose, and fructose. Recently, lactic acid has been considered to be an important raw material for the production of biodegradable lactide polymer. The fermentation experiments were carried out in a 3 litres fermentor (Biostat B Model under anaerobic condition with stirring speed of 50 rpm, temperature at 40oC, and pH of 6.00. Effect of feed concentration on lactic acid production, bacterial growth, substrate utilisation and productivity was studied. The results obtained from fed- batch culture fermentation showed that the maximum lactic acid productivity was 0.44 g/L.h for feed concentration of 90 g/L at 48 hours. Whereas the lactic acid productivity obtained from fed-batch culture was twice and half fold higher than that of batch culture productivity.  Buangan jus nanas mengandung komponen yang berharga terutama sukrosa, glukosa, dan fruktosa. Asam laktat adalah bahan baku yang terbaru dan penting untuk dibuat sebagai polimer laktat yang dapat terdegradasi oleh lingkungan. Percobaan dilakukan pada fermentor 3 liter (Model Biostat B di bawah kondisi anaerob dengan kecepatan pengadukan 50 rpm, temperatur 40oC, dan pH 6,00. Pengaruh konsentrasi umpan terhadap produksi asam laktat, pertumbuhan mikroba, pengggunaan substrat dan produktivitas telah dipelajari. Hasil yang didapatkan pada fermentasi dengan menggunakan sistem fed-batch menunjukkan bahwa produktivitas asam laktat maksimum adalah 0.44 g/L,jam dengan konsentrasi umpan, 90 g/L pada waktu 48 jam. Bahkan produktivitas asam laktat yang didapat pada kultur fed-batch lebih tinggi 2,5 kali dari pada proses menggunakan sistem batch

  4. Batch fabrication of disposable screen printed SERS arrays.

    Science.gov (United States)

    Qu, Lu-Lu; Li, Da-Wei; Xue, Jin-Qun; Zhai, Wen-Lei; Fossey, John S; Long, Yi-Tao

    2012-03-07

    A novel facile method of fabricating disposable and highly reproducible surface-enhanced Raman spectroscopy (SERS) arrays using screen printing was explored. The screen printing ink containing silver nanoparticles was prepared and printed on supporting materials by a screen printing process to fabricate SERS arrays (6 × 10 printed spots) in large batches. The fabrication conditions, SERS performance and application of these arrays were systematically investigated, and a detection limit of 1.6 × 10(-13) M for rhodamine 6G could be achieved. Moreover, the screen printed SERS arrays exhibited high reproducibility and stability, the spot-to-spot SERS signals showed that the intensity variation was less than 10% and SERS performance could be maintained over 12 weeks. Portable high-throughput analysis of biological samples was accomplished using these disposable screen printed SERS arrays.

  5. Following an Optimal Batch Bioreactor Operations Model

    DEFF Research Database (Denmark)

    Ibarra-Junquera, V.; Jørgensen, Sten Bay; Virgen-Ortíz, J.J.

    2012-01-01

    -batch reactor for biomass production is studied using a differential geometry approach. The maximization problem is solved by handling both the optimal filling policy and substrate concentration in the inlet stream. In order to follow the OBBOM, a master–slave synchronization is used. The OBBOM is considered...... as the master system which includes the optimal cultivation trajectory for the feed flow rate and the substrate concentration. The “real” bioreactor, the one with unknown dynamics and perturbations, is considered as the slave system. Finally, the controller is designed such that the real bioreactor...

  6. Picosecond and nanosecond pulse delivery through a hollow-core Negative Curvature Fiber for micro-machining applications.

    Science.gov (United States)

    Jaworski, Piotr; Yu, Fei; Maier, Robert R J; Wadsworth, William J; Knight, Jonathan C; Shephard, Jonathan D; Hand, Duncan P

    2013-09-23

    We present high average power picosecond and nanosecond pulse delivery at 1030 nm and 1064 nm wavelengths respectively through a novel hollow-core Negative Curvature Fiber (NCF) for high-precision micro-machining applications. Picosecond pulses with an average power above 36 W and energies of 92 µJ, corresponding to a peak power density of 1.5 TWcm⁻² have been transmitted through the fiber without introducing any damage to the input and output fiber end-faces. High-energy nanosecond pulses (>1 mJ), which are ideal for micro-machining have been successfully delivered through the NCF with a coupling efficiency of 92%. Picosecond and nanosecond pulse delivery have been demonstrated in fiber-based laser micro-machining of fused silica, aluminum and titanium.

  7. Arrayed architectures for multi-stage Si-micromachined high-flow Knudsen pumps

    International Nuclear Information System (INIS)

    Qin, Yutao; An, Seungdo; Gianchandani, Yogesh B

    2015-01-01

    This paper reports an evaluation and a comparison of two architectures for implementing Si-micromachined high-flow Knudsen pumps. Knudsen pumps, which operate on the principle of thermal transpiration, have been shown to have great promise for micro-scale gas phase fluidic systems such as micro gas chromatographs. Simultaneously achieving both a high flow rate and adequate blocking pressure has been a persistent challenge, which is addressed in this work by combining multiple pumps in series and addressing the resulting challenges in thermal management. The basic building block is a Si-micromachined pump with  ≈100 000 parallel channels in a 4 mm  ×  6 mm footprint. In the primary approach, multiple pump stages are stacked vertically with interleaved Si-micromachined spacers. A stacked 4-stage Knudsen pump has a form factor of 10 mm  ×  8 mm  ×  6 mm. In an alternate approach, multiple stages are arranged in a planar array. The experimental results demonstrate multiplication of the output pressure head with the number of stages, while the flow rate is maintained. For example, a stacked 4-stage Knudsen pump with 8 W power operated at atmospheric pressure provided a blocking pressure of 0.255 kPa, which was 3.6  ×  of that provided by a single-stage pump with 2 W power; while both provided a  ≈  30 sccm maximum flow rate. The performance can be customized for practical applications such as micro gas chromatography. (paper)

  8. Femtosecond laser 3D micromachining for microfluidic and optofluidic applications

    CERN Document Server

    Sugioka, Koji

    2013-01-01

    Femtosecond lasers opened up new avenue in materials processing due to its unique features of ultrashort pulse width and extremely high peak intensity. One of the most important features of femtosecond laser processing is that strong absorption can be induced even by materials which are transparent to the femtosecond laser beam due to nonlinear multiphoton absorption. The multiphoton absorption allows us to perform not only surface but also three-dimensionally internal microfabrication of transparent materials such as glass. This capability makes it possible to directly fabricate three-dimensi

  9. A versatile multi-user polyimide surface micromachinning process for MEMS applications

    KAUST Repository

    Carreno, Armando Arpys Arevalo

    2015-04-01

    This paper reports a versatile multi-user micro-fabrication process for MEMS devices, the \\'Polyimide MEMS Multi-User Process\\' (PiMMPs). The reported process uses polyimide as the structural material and three separate metallization layers that can be interconnected depending on the desired application. This process enables for the first time the development of out-of-plane compliant mechanisms that can be designed using six different physical principles for actuation and sensing on a wafer from a single fabrication run. These principles are electrostatic motion, thermal bimorph actuation, capacitive sensing, magnetic sensing, thermocouple-based sensing and radio frequency transmission and reception. © 2015 IEEE.

  10. Femtosecond laser micromachining of compound parabolic concentrator fiber tipped glucose sensors

    DEFF Research Database (Denmark)

    Hassan, Hafeez Ul; Lacraz, Amédée; Kalli, Kyriacos

    2017-01-01

    We report on highly accurate femtosecond (fs) laser micromachining of a compound parabolic concentrator (CPC) fiber tip on a polymer optical fiber (POF). The accuracy is reflected in an unprecedented correspondence between the numerically predicted and experimentally found improvement in fluoresc.......5, which is only 11.6% from the predicted value. Earlier state-of-the-art fabrication of the CPC-shaped tip by fiber tapering was of so poor quality that the actual improvement was 43% lower than the predicted improvement of the ideal CPC shape....

  11. Wideband acoustic activation and detection of droplet vaporization events using a capacitive micromachined ultrasonic transducer

    Science.gov (United States)

    Novell, Anthony; Arena, Christopher B.; Oralkan, Omer; Dayton, Paul A.

    2016-01-01

    An ongoing challenge exists in understanding and optimizing the acoustic droplet vaporization (ADV) process to enhance contrast agent effectiveness for biomedical applications. Acoustic signatures from vaporization events can be identified and differentiated from microbubble or tissue signals based on their frequency content. The present study exploited the wide bandwidth of a 128-element capacitive micromachined ultrasonic transducer (CMUT) array for activation (8 MHz) and real-time imaging (1 MHz) of ADV events from droplets circulating in a tube. Compared to a commercial piezoelectric probe, the CMUT array provides a substantial increase of the contrast-to-noise ratio. PMID:27369143

  12. Non-Lithographic Silicon Micromachining Using Inkjet and Chemical Etching

    Directory of Open Access Journals (Sweden)

    Sasha Hoshian

    2016-12-01

    Full Text Available We introduce a non-lithographical and vacuum-free method to pattern silicon. The method combines inkjet printing and metal assisted chemical etching (MaCE; we call this method “INKMAC”. A commercial silver ink is printed on top of a silicon surface to create the catalytic patterns for MaCE. The MaCE process leaves behind a set of silicon nanowires in the shape of the inkjet printed micrometer scale pattern. We further show how a potassium hydroxide (KOH wet etching process can be used to rapidly etch away the nanowires, producing fully opened cavities and channels in the shape of the original printed pattern. We show how the printed lines (width 50–100 µm can be etched into functional silicon microfluidic channels with different depths (10–40 µm with aspect ratios close to one. We also used individual droplets (minimum diameter 30 µm to produce cavities with a depth of 60 µm and an aspect ratio of two. Further, we discuss using the structured silicon substrate as a template for polymer replication to produce superhydrophobic surfaces.

  13. Nickel silicide thin films as masking and structural layers for silicon bulk micro-machining by potassium hydroxide wet etching

    International Nuclear Information System (INIS)

    Bhaskaran, M; Sriram, S; Sim, L W

    2008-01-01

    This paper studies the feasibility of using titanium and nickel silicide thin films as mask materials for silicon bulk micro-machining. Thin films of nickel silicide were found to be more resistant to wet etching in potassium hydroxide. The use of nickel silicide as a structural material, by fabricating micro-beams of varying dimensions, is demonstrated. The micro-structures were realized using these thin films with wet etching using potassium hydroxide solution on (1 0 0) and (1 1 0) silicon substrates. These results show that nickel silicide is a suitable alternative to silicon nitride for silicon bulk micro-machining

  14. Numerical modelling of micro-machining of f.c.c. single crystal: Influence of strain gradients

    KAUST Repository

    Demiral, Murat

    2014-11-01

    A micro-machining process becomes increasingly important with the continuous miniaturization of components used in various fields from military to civilian applications. To characterise underlying micromechanics, a 3D finite-element model of orthogonal micro-machining of f.c.c. single crystal copper was developed. The model was implemented in a commercial software ABAQUS/Explicit employing a user-defined subroutine VUMAT. Strain-gradient crystal-plasticity and conventional crystal-plasticity theories were used to demonstrate the influence of pre-existing and evolved strain gradients on the cutting process for different combinations of crystal orientations and cutting directions. Crown Copyright © 2014.

  15. Erosion resistant anti-ice surfaces generated by ultra short laser pulses

    NARCIS (Netherlands)

    Del Cerro, D.A.; Römer, G.R.B.E.; Huis in't Veld, A.J.

    2010-01-01

    Wetting properties of a wide range of materials can be modified by accurate laser micromachining with ultra short laser pulses. Controlling the surface topography in a micro and sub-micrometer scale allows the generation of water-repellent surfaces, which remain dry and prevent ice accumulation

  16. Biological Treatment of Leachate using Sequencing Batch Reactor

    Directory of Open Access Journals (Sweden)

    WDMC Perera

    2014-12-01

    Full Text Available Normal 0 false false false EN-US X-NONE TA Abstract   In Sri Lanka municipal solid waste is generally disposed in poorly managed open dumps which lack liner systems and leachate collection systems. Rain water percolates through the waste layers to produce leachate which drains in to ground water and finally to nearby water bodies, degrading the quality of water. Leachate thus has become a major environmental concern in municipal waste management and treatment of leachate is a major challenge for the existing and proposed landfill sites.   The study was conducted to assess the feasibility of the usage of the Sequencing Batch Reactor in the treatment of the landfill leachate up to the proposed levels in the draft report of “Proposed Sri Lankan standard for landfill leachate to be disposed to the inland waters". Leachate collected from the open dumpsite at Meethotamulla, Western Province, Sri Lanka was used for leachate characterization.   SBR was constructed with a 10-liter working volume operated in an 18 hour cycle mode and each cycle consists of 15hours of aerobic, 2h settle and 0.5 h of fill/decant stages. The Dissolved Oxygen level within the SBR was maintained at 2 mg/l through the aerobic stage. Infeed was diluted with water during the acclimatization period and a leachate to water ratio of 55:45 was maintained. The removal efficiencies for different parameters were; COD (90.5%, BOD (92.6%, TS (92.1%, Conductivity (83.9%, Alkalinity (97.4%, Hardness (82.2%, Mg (80.5%, Fe (94.2%, Zn (63.4%, Cr (31.69%, Pb (99.6%, Sulphate (98.9%, and Phosphorus (71.4% respectively. In addition Ni and Cd were removed completely during a single SBR cycle. Thus the dilution of leachate in the dumpsites using municipal wastewater, groundwater or rainwater was identified as the most cost effective dilution methods. The effluent from the Sequencing batch reactor is proposed to be further treated using a constructed wetland before releasing to surface water.

  17. A comparative study of the physical and chemical properties of nano-sized ZnO particles from multiple batches of three commercial products

    Science.gov (United States)

    Yin, Hong; Coleman, Victoria A.; Casey, Phil S.; Angel, Brad; Catchpoole, Heather J.; Waddington, Lynne; McCall, Maxine J.

    2015-02-01

    Given the broad commercial applications for ZnO nanomaterials, accurate attribution of physicochemical characteristics that induce toxic effects is particularly important. We report on the physicochemical properties of three commercial nano-ZnO products: Z-COTE and Z-COTE HP1 from BASF, and Nanosun from Micronisers, and, for reference, "bulk" ZnO from Sigma-Aldrich. Z-COTE, Nanosun and "bulk" consist of uncoated particles with different sizes, while Z-COTE HP1 consists of nanoparticles with a hydrophobic coating. Specific batches of these ZnO products were included in the OECD Sponsorship Programme to test manufactured nanomaterials. In order to identify properties potentially susceptible to variations between production runs, three additional batches of Z-COTE and Nanosun and two additional batches of Z-COTE HP1 were also investigated here. In general, all products showed little variation between batches for properties measured from powdered samples, but batch variations in the amount of surface coating were evident for the coated Z-COTE HP1. Properties measured with samples dispersed in liquids (agglomeration, photocatalytic activity, dissolution) were highly dependent on dispersion protocols, and this made it difficult to differentiate between differences due to dispersion and due to batches. However, batch-sensitive properties did appear to be present in Z-COTE and Z-COTE HP1 (photocatalytic activity), and Nanosun (dissolution). Intra-batch time and/or storage-dependent changes in the applied surface coating, noted specifically for the OECD batch of Z-COTE HP1, highlight the need for best practice when storing and accessing stocks of nano products. Awareness of inter-batch and intra-batch variability is essential for commercial applications and for nanotoxicological studies aimed at identifying links between physicochemical properties and any adverse effects in biological systems.

  18. Fabrication of corrugated artificial insect wings using laser micromachined molds

    International Nuclear Information System (INIS)

    Tanaka, Hiroto; Wood, Robert J

    2010-01-01

    This paper describes the fabrication of an artificial insect wing with a rich set of topological features by micromolding a thermosetting resin. An example 12 mm long hoverfly-like wing is fabricated with 50–125 µm vein heights and 100 µm corrugation heights. The solid veins and membrane were simultaneously formed and integrated by a single molding process. Employing a layered laser ablation technique, three-dimensional molds were created with 5 µm resolution in height. Safe demolding of the wing was achieved with a water-soluble sacrificial layer on the mold. Measured surface profiles of the wing matched those of the molds, demonstrating the high replication accuracy of this molding process. Using this process, the morphological features of insect wings can be replicated at-scale with high precision, enabling parametric experiments of the functional morphology of insect wings. This fabrication capability also makes it possible to create a variety of wing types for micro air vehicles on scales similar to insects.

  19. First In Vivo Use of a Capacitive Micromachined Ultrasound Transducer Array–Based Imaging and Ablation Catheter

    Science.gov (United States)

    Stephens, Douglas N.; Truong, Uyen T.; Nikoozadeh, Amin; Oralkan, Ömer; Seo, Chi Hyung; Cannata, Jonathan; Dentinger, Aaron; Thomenius, Kai; de la Rama, Alan; Nguyen, Tho; Lin, Feng; Khuri-Yakub, Pierre; Mahajan, Aman; Shivkumar, Kalyanam; O’Donnell, Matt; Sahn, David J.

    2012-01-01

    Objectives The primary objective was to test in vivo for the first time the general operation of a new multifunctional intracardiac echocardiography (ICE) catheter constructed with a microlinear capacitive micromachined ultrasound transducer (ML-CMUT) imaging array. Secondarily, we examined the compatibility of this catheter with electroanatomic mapping (EAM) guidance and also as a radiofrequency ablation (RFA) catheter. Preliminary thermal strain imaging (TSI)-derived temperature data were obtained from within the endocardium simultaneously during RFA to show the feasibility of direct ablation guidance procedures. Methods The new 9F forward-looking ICE catheter was constructed with 3 complementary technologies: a CMUT imaging array with a custom electronic array buffer, catheter surface electrodes for EAM guidance, and a special ablation tip, that permits simultaneous TSI and RFA. In vivo imaging studies of 5 anesthetized porcine models with 5 CMUT catheters were performed. Results The ML-CMUT ICE catheter provided high-resolution real-time wideband 2-dimensional (2D) images at greater than 8 MHz and is capable of both RFA and EAM guidance. Although the 24-element array aperture dimension is only 1.5 mm, the imaging depth of penetration is greater than 30 mm. The specially designed ultrasound-compatible metalized plastic tip allowed simultaneous imaging during ablation and direct acquisition of TSI data for tissue ablation temperatures. Postprocessing analysis showed a first-order correlation between TSI and temperature, permitting early development temperature-time relationships at specific myocardial ablation sites. Conclusions Multifunctional forward-looking ML-CMUT ICE catheters, with simultaneous intracardiac guidance, ultrasound imaging, and RFA, may offer a new means to improve interventional ablation procedures. PMID:22298868

  20. First in vivo use of a capacitive micromachined ultrasound transducer array-based imaging and ablation catheter.

    Science.gov (United States)

    Stephens, Douglas N; Truong, Uyen T; Nikoozadeh, Amin; Oralkan, Omer; Seo, Chi Hyung; Cannata, Jonathan; Dentinger, Aaron; Thomenius, Kai; de la Rama, Alan; Nguyen, Tho; Lin, Feng; Khuri-Yakub, Pierre; Mahajan, Aman; Shivkumar, Kalyanam; O'Donnell, Matt; Sahn, David J

    2012-02-01

    The primary objective was to test in vivo for the first time the general operation of a new multifunctional intracardiac echocardiography (ICE) catheter constructed with a microlinear capacitive micromachined ultrasound transducer (ML-CMUT) imaging array. Secondarily, we examined the compatibility of this catheter with electroanatomic mapping (EAM) guidance and also as a radiofrequency ablation (RFA) catheter. Preliminary thermal strain imaging (TSI)-derived temperature data were obtained from within the endocardium simultaneously during RFA to show the feasibility of direct ablation guidance procedures. The new 9F forward-looking ICE catheter was constructed with 3 complementary technologies: a CMUT imaging array with a custom electronic array buffer, catheter surface electrodes for EAM guidance, and a special ablation tip, that permits simultaneous TSI and RFA. In vivo imaging studies of 5 anesthetized porcine models with 5 CMUT catheters were performed. The ML-CMUT ICE catheter provided high-resolution real-time wideband 2-dimensional (2D) images at greater than 8 MHz and is capable of both RFA and EAM guidance. Although the 24-element array aperture dimension is only 1.5 mm, the imaging depth of penetration is greater than 30 mm. The specially designed ultrasound-compatible metalized plastic tip allowed simultaneous imaging during ablation and direct acquisition of TSI data for tissue ablation temperatures. Postprocessing analysis showed a first-order correlation between TSI and temperature, permitting early development temperature-time relationships at specific myocardial ablation sites. Multifunctional forward-looking ML-CMUT ICE catheters, with simultaneous intracardiac guidance, ultrasound imaging, and RFA, may offer a new means to improve interventional ablation procedures.

  1. Neurovascular modeling: small-batch manufacturing of silicone vascular replicas.

    Science.gov (United States)

    Chueh, J Y; Wakhloo, A K; Gounis, M J

    2009-06-01

    Realistic, population based cerebrovascular replicas are required for the development of neuroendovascular devices. The objective of this work was to develop an efficient methodology for manufacturing realistic cerebrovascular replicas. Brain MR angiography data from 20 patients were acquired. The centerline of the vasculature was calculated, and geometric parameters were measured to describe quantitatively the internal carotid artery (ICA) siphon. A representative model was created on the basis of the quantitative measurements. Using this virtual model, we designed a mold with core-shell structure and converted it into a physical object by fused-deposit manufacturing. Vascular replicas were created by injection molding of different silicones. Mechanical properties, including the stiffness and luminal coefficient of friction, were measured. The average diameter, length, and curvature of the ICA siphon were 4.15 +/- 0.09 mm, 22.60 +/- 0.79 mm, and 0.34 +/- 0.02 mm(-1) (average +/- standard error of the mean), respectively. From these image datasets, we created a median virtual model, which was transformed into a physical replica by an efficient batch-manufacturing process. The coefficient of friction of the luminal surface of the replica was reduced by up to 55% by using liquid silicone rubber coatings. The modulus ranged from 0.67 to 1.15 MPa compared with 0.42 MPa from human postmortem studies, depending on the material used to make the replica. Population-representative, smooth, and true-to-scale silicone arterial replicas with uniform wall thickness were successfully built for in vitro neurointerventional device-testing by using a batch-manufacturing process.

  2. A LabVIEWTM-based scanning and control system for proton beam micromachining

    International Nuclear Information System (INIS)

    Bettiol, Andrew A.; Kan, J.A. van; Sum, T.C.; Watt, F.

    2001-01-01

    LabVIEW TM is steadily gaining in popularity as the programming language of choice for scientific data acquisition and control. This is due to the vast array of measurement instruments and data acquisition cards supported by the LabVIEW TM environment, and the relative ease with which advanced software can be programmed. Furthermore, virtual instruments that are designed for a given system can be easily ported to other LabVIEW TM platforms and hardware. This paper describes the new LabVIEW TM based scanning and control system developed specifically for proton beam micromachining (PBM) applications. The new system is capable of scanning figures at 16-bit resolution with improved sub-microsecond scan rates. Support for electrostatic beam blanking and external dose normalization using a TTL signal have been implemented. The new software incorporates a semi-automated dose calibration system, and a number of novel dose normalization methods. Limitations of the current beam scanning hardware are discussed in light of new results obtained from micromachining experiments performed in SU-8 photoresist

  3. Millimeter length micromachining using a heavy ion nuclear microprobe with standard magnetic scanning

    Energy Technology Data Exchange (ETDEWEB)

    Nesprías, F. [Gerencia de Investigación y Aplicaciones, Comisión Nacional de Energía Atómica, Av. Gral Paz 1499 (1650), San Martín, Buenos Aires (Argentina); Debray, M.E., E-mail: debray@tandar.cnea.gov.ar [Gerencia de Investigación y Aplicaciones, Comisión Nacional de Energía Atómica, Av. Gral Paz 1499 (1650), San Martín, Buenos Aires (Argentina); Escuela de Ciencia y Tecnología. Universidad Nacional de Gral. San Martín, M. De Irigoyen 3100 (1650), San Martín, Buenos Aires (Argentina); Davidson, J. [Gerencia de Investigación y Aplicaciones, Comisión Nacional de Energía Atómica, Av. Gral Paz 1499 (1650), San Martín, Buenos Aires (Argentina); CONICET, Avda. Rivadavia 1917 (C1033AAJ), Ciudad Autónoma de Buenos Aires (Argentina); Kreiner, A.J. [Gerencia de Investigación y Aplicaciones, Comisión Nacional de Energía Atómica, Av. Gral Paz 1499 (1650), San Martín, Buenos Aires (Argentina); Escuela de Ciencia y Tecnología. Universidad Nacional de Gral. San Martín, M. De Irigoyen 3100 (1650), San Martín, Buenos Aires (Argentina); CONICET, Avda. Rivadavia 1917 (C1033AAJ), Ciudad Autónoma de Buenos Aires (Argentina); and others

    2013-04-01

    In order to increase the scanning length of our microprobe, we have developed an irradiation procedure suitable for use in any nuclear microprobe, extending at least up to 400% the length of our heavy ion direct writing facility using standard magnetic exploration. Although this method is limited to patterns of a few millimeters in only one direction, it is useful for the manufacture of curved waveguides, optical devices such Mach–Zehnder modulators, directional couplers as well as channels for micro-fluidic applications. As an example, this technique was applied to the fabrication of 3 mm 3D-Mach–Zehnder modulators in lithium niobate with short Y input/output branches and long shaped parallel-capacitor control electrodes. To extend and improve the quality of the machined structures we developed new scanning control software in LabView™ platform. The new code supports an external dose normalization, electrostatic beam blanking and is capable of scanning figures at 16 bit resolution using a National Instruments™ PCI-6731 High-Speed I/O card. A deep and vertical micromachining process using swift {sup 35}Cl ions 70 MeV bombarding energy and direct write patterning was performed on LiNbO{sub 3}, a material which exhibits a strong natural anisotropy to conventional etching. The micromachined structures show the feasibility of this method for manufacturing micro-fluidic channels as well.

  4. Differential search algorithm-based parametric optimization of electrochemical micromachining processes

    Directory of Open Access Journals (Sweden)

    Debkalpa Goswami

    2014-01-01

    Full Text Available Electrochemical micromachining (EMM appears to be a very promising micromachining process for having higher machining rate, better precision and control, reliability, flexibility, environmental acceptability, and capability of machining a wide range of materials. It permits machining of chemically resistant materials, like titanium, copper alloys, super alloys and stainless steel to be used in biomedical, electronic, micro-electromechanical system and nano-electromechanical system applications. Therefore, the optimal use of an EMM process for achieving enhanced machining rate and improved profile accuracy demands selection of its various machining parameters. Various optimization tools, primarily Derringer’s desirability function approach have been employed by the past researchers for deriving the best parametric settings of EMM processes, which inherently lead to sub-optimal or near optimal solutions. In this paper, an attempt is made to apply an almost new optimization tool, i.e. differential search algorithm (DSA for parametric optimization of three EMM processes. A comparative study of optimization performance between DSA, genetic algorithm and desirability function approach proves the wide acceptability of DSA as a global optimization tool.

  5. Development of an electrochemical micromachining instrument for the confined etching techniques.

    Science.gov (United States)

    Zhou, Hang; Lai, Lei-Jie; Zhao, Xiang-Hui; Zhu, Li-Min

    2014-04-01

    This study proposes an electrochemical micromachining instrument for two confined etching techniques, namely, confined etchant layer technique (CELT) and electrochemical wet stamping (E-WETS). The proposed instrument consists of a granite bridge base, a Z-axis coarse/fine dual stage, and a force sensor. The Z-axis coarse/fine dual stage controls the vertical movement of the substrate with nanometer accuracy. The force sensor measures the contact force between the mold and the substrate. A contact detection method based on a digital lock-in amplifier is developed to make the mold-substrate contact within a five-nanometer range in CELT, and a force feedback controller is implemented to keep the contact force in E-WETS at a constant value with a noise of less than 0.2 mN. With the use of the confined etching techniques, a microlens array and a curvilinear ridge microstructure are successfully fabricated with high accuracy, thus demonstrating the promising performance of the proposed micromachining instrument.

  6. Optical waveguides fabricated in Cr:LiSAF by femtosecond laser micromachining

    Science.gov (United States)

    Biasetti, Demian A.; Di Liscia, Emiliano J.; Torchia, Gustavo A.

    2017-11-01

    In this work we present the fabrication of double-track type II waveguides written in 1% doped Cr:LiSrAlF6 (Cr:LiSAF) crystal by femtosecond laser micromachining. We studied waveguides fabricated at energies from 1 to 7 μJ per pulse at writing speeds of 15-45 μm/s. We found good wave-guiding performance for both, Transversal Magnetic (TM) and Transversal Electric (TE) polarization modes as well as acceptable losses according to the expected values addressed to technological applications. Also, we performed a high-resolution μ-luminescence waveguide cross-section mapping between the tracks, in order to identify possible spectral changes caused for active ions Cr3+ corresponding to the 4T2 →4A2 vibronic transition in the focal volume zone, due to induced anisotropic graded stress. Finally, their lifetimes were measured for bulk as well as for waveguide trapped ions. We found that for the range of parameters of ultra-short micromachining used, the Cr3+ ions embedded in the waveguides remained spectroscopically unchanged compared with those observed in bulk material.

  7. A Novel Piezo-Actuator-Sensor Micromachine for Mechanical Characterization of Micro-Specimens

    Directory of Open Access Journals (Sweden)

    Leila Ladani

    2010-12-01

    Full Text Available Difficulties associated with testing and characterization of materials at microscale demands for new technologies and devices that are capable of measuring forces and strains at microscale. To address this issue, a novel electroactive-based micro-electro-mechanical machine is designed. The micromachine is comprised of two electroactive (piezoelectric micro-elements mounted on a rigid frame. Electrical activation of one of the elements causes it to expand and induce a stress in the intervening micro-specimen. The response of the microspecimen to the stress is measured by the deformation and thereby voltage/resistance induced in the second electro-active element. The concept is theoretically proven using analytical modeling in conjunction with non-linear, three dimensional finite element analyses for the micromachine. Correlation of the output voltage to the specimen stiffness is shown. It is also demonstrated through finite element and analytical analysis that this technique is capable of detecting non-linear behavior of materials. A characteristic curve for an isotropic specimen exhibiting linear elastic behavior is developed. Application of the proposed device in measuring coefficient of thermal expansion is explored and analytical analysis is conducted.

  8. Interactive and Batch Analysis at DESY

    Science.gov (United States)

    Künne, K.

    Besides the data taking and reconstruction the analysis of the Physics Data is a major part in Physics Computing. Currently a new structure, which should last for the next years (maybe the next millenium), is introduced in the computing for Physics Analysis at DESY, which closely follows a Client-Server-Model, and which is based on the Workgroup-Server-Concept (first introduced at CERN). The talk will give an overview about this new structure, which includes File-Servers, Workgroup-Servers, and Batch-Servers. Special emphasis will be given to the handling of different classes of data inside of such a distributed system. The important point here is to avoid unnecessary network traffic. Other key topics include management of that distributed system and load balancing issues. Also presented in this talk are experiences with that system and future developments.

  9. Batch Cultivation Model for Biopolymer Production

    Directory of Open Access Journals (Sweden)

    C. E. Torres-Cerna

    2017-04-01

    Full Text Available This paper presents a mathematical model to evaluate the kinetics of two different Pseudomonas putida strains, wild and mutant-type for the microbial production of polyhydroxyalkanoates (PHAs. Model parameters were estimated to represent adequately experimental data from the batch reactor using the differential evolution algorithm. Based on the mathematical model with the best-fit parameter values, simulations suggested that the high production of PHA by the mutant strain can be attributed not only to the higher production of PHA but also to a reduction in the consumption rate of the substrates of approximately 66 %. Remarkably, the cell growth rate value is higher for the wild type than the mutant type, suggesting that the PHA increase is not only to an increase in the production rate but also to the metabolism of the cells. This mathematical model advances comprehension of the PHA production capacity by P. putida paving the road towards environmentally friendly plastics.

  10. Maximum thermodynamic efficiency problem in batch distillation

    Directory of Open Access Journals (Sweden)

    J. C. Zavala-Loría

    2011-06-01

    Full Text Available A dynamic batch distillation study of the non-ideal mixture Ethanol-Water is presented. The objective of the study was to calculate an average thermodynamic efficiency of the process under an optimal constant reflux policy and the objective function includes a given production time in order to obtain the desired product quality (measured as the average mole fraction of the accumulated product. An expression for computing the thermodynamic efficiency is presented. The simulation of the column uses a mathematical model considering the complete dynamics of the operation and the problem of optimal control resulting in a non-linear programming problem. A dynamic optimization technique based on a SQP method was used to solve the problem. The average thermodynamic efficiency for the separation process under the conditions presented was 37.95%.

  11. Optimizing Resource Utilization in Grid Batch Systems

    International Nuclear Information System (INIS)

    Gellrich, Andreas

    2012-01-01

    On Grid sites, the requirements of the computing tasks (jobs) to computing, storage, and network resources differ widely. For instance Monte Carlo production jobs are almost purely CPU-bound, whereas physics analysis jobs demand high data rates. In order to optimize the utilization of the compute node resources, jobs must be distributed intelligently over the nodes. Although the job resource requirements cannot be deduced directly, jobs are mapped to POSIX UID/GID according to the VO, VOMS group and role information contained in the VOMS proxy. The UID/GID then allows to distinguish jobs, if users are using VOMS proxies as planned by the VO management, e.g. ‘role=production’ for Monte Carlo jobs. It is possible to setup and configure batch systems (queuing system and scheduler) at Grid sites based on these considerations although scaling limits were observed with the scheduler MAUI. In tests these limitations could be overcome with a home-made scheduler.

  12. Spatial and interannual variability in Baltic sprat batch fecundity

    DEFF Research Database (Denmark)

    Haslob, H.; Tomkiewicz, Jonna; Hinrichsen, H.H.

    2011-01-01

    and ambient temperature explained 70% of variability in absolute batch fecundity. Oxygen content and fish condition were not related to sprat batch fecundity. Additionally, a negative effect of stock size on sprat batch fecundity in the Bornholm Basin was revealed. The obtained data and results are important...... in the central Baltic Sea, namely the Bornholm Basin, Gdansk Deep and Southern Gotland Basin. Environmental parameters such as hydrography, fish condition and stock density were tested in order to investigate the observed variability in sprat fecundity. Absolute batch fecundity was found to be positively related...

  13. Survey on batch-to-batch variation in spray paints: a collaborative study.

    Science.gov (United States)

    Muehlethaler, Cyril; Massonnet, Geneviève; Deviterne, Marie; Bradley, Maureen; Herrero, Ana; de Lezana, Itxaso Diaz; Lauper, Sandrine; Dubois, Damien; Geyer-Lippmann, Jochen; Ketterer, Sonja; Milet, Stéphane; Bertrand, Magali; Langer, Wolfgang; Plage, Bernd; Gorzawski, Gabriele; Lamothe, Véronique; Marsh, Louissa; Turunen, Raija

    2013-06-10

    This study represents the most extensive analysis of batch-to-batch variations in spray paint samples to date. The survey was performed as a collaborative project of the ENFSI (European Network of Forensic Science Institutes) Paint and Glass Working Group (EPG) and involved 11 laboratories. Several studies have already shown that paint samples of similar color but from different manufacturers can usually be differentiated using an appropriate analytical sequence. The discrimination of paints from the same manufacturer and color (batch-to-batch variations) is of great interest and these data are seldom found in the literature. This survey concerns the analysis of batches from different color groups (white, papaya (special shade of orange), red and black) with a wide range of analytical techniques and leads to the following conclusions. Colored batch samples are more likely to be differentiated since their pigment composition is more complex (pigment mixtures, added pigments) and therefore subject to variations. These variations may occur during the paint production but may also occur when checking the paint shade in quality control processes. For these samples, techniques aimed at color/pigment(s) characterization (optical microscopy, microspectrophotometry (MSP), Raman spectroscopy) provide better discrimination than techniques aimed at the organic (binder) or inorganic composition (fourier transform infrared spectroscopy (FTIR) or elemental analysis (SEM - scanning electron microscopy and XRF - X-ray fluorescence)). White samples contain mainly titanium dioxide as a pigment and the main differentiation is based on the binder composition (CH stretches) detected either by FTIR or Raman. The inorganic composition (elemental analysis) also provides some discrimination. Black samples contain mainly carbon black as a pigment and are problematic with most of the spectroscopic techniques. In this case, pyrolysis-GC/MS represents the best technique to detect differences

  14. Determination of young's modulus of PZT and CO80Ni20 thin films by means of micromachined cantilevers

    NARCIS (Netherlands)

    Nazeer, H.; Abelmann, Leon; Tas, Niels Roelof; van Honschoten, J.W.; Siekman, Martin Herman; Elwenspoek, Michael Curt

    2009-01-01

    This paper presents a technique to determine the Young’s modulus and residual stress of thin films using a simple micromachined silicon cantilever as the test structure. An analytical relation was developed based on the shift in resonance frequency caused by the addition of a thin film on the

  15. A passive micromachined device for alignment of arrays of single-mode fibers for hermetic photonic packaging - the CLASP concept

    Energy Technology Data Exchange (ETDEWEB)

    Seigal, P.K.; Kravitz, S.H.; Word, J.C.; Bauer, T.M. [and others

    1997-02-01

    A micro-machined fiber alignment device, called CLASP (Capture and Locking Alignment Spring Positioner) has been fabricated. It uses a nickel leaf spring to passively capture vertical arrays of single-mode fibers with {approximately} 2 {mu}m accuracy.

  16. Bioprocess iterative batch-to-batch optimization based on hybrid parametric/nonparametric models.

    Science.gov (United States)

    Teixeira, Ana P; Clemente, João J; Cunha, António E; Carrondo, Manuel J T; Oliveira, Rui

    2006-01-01

    This paper presents a novel method for iterative batch-to-batch dynamic optimization of bioprocesses. The relationship between process performance and control inputs is established by means of hybrid grey-box models combining parametric and nonparametric structures. The bioreactor dynamics are defined by material balance equations, whereas the cell population subsystem is represented by an adjustable mixture of nonparametric and parametric models. Thus optimizations are possible without detailed mechanistic knowledge concerning the biological system. A clustering technique is used to supervise the reliability of the nonparametric subsystem during the optimization. Whenever the nonparametric outputs are unreliable, the objective function is penalized. The technique was evaluated with three simulation case studies. The overall results suggest that the convergence to the optimal process performance may be achieved after a small number of batches. The model unreliability risk constraint along with sampling scheduling are crucial to minimize the experimental effort required to attain a given process performance. In general terms, it may be concluded that the proposed method broadens the application of the hybrid parametric/nonparametric modeling technique to "newer" processes with higher potential for optimization.

  17. Batch process. Batch process used in a beer brewery; Biru kojo no bacchi purosesu

    Energy Technology Data Exchange (ETDEWEB)

    Kihara, K. [Kirin Engneering Co. Ltd. (Japan)

    1997-09-05

    In a beer brewing process, there is a system in which unit operation of chemical engineering is combined with the techniques of food and fermentation engineering in order to brew beer meeting the quality concept. This paper introduces the characteristics of a batch system used in the brewing of beer and the control method for the brewing of beer. The characteristics of the batch system used in a beer brewing process are the following three. In order to minimize the quality variation ascribed to the raw materials and the process, the materials are blended in various parts of the system. In the saccharification step which determines the quality of beer, two methods, i.e. a batch method and a continuous method are used, and beer brewing companies employ a saccharification system meeting the condition for attaining a desired quality of their own products. Two mashing systems are operated at different cycles shifted by half cycle from each other, not starting both at a time, so as to level the peaks of the utilities, whereby the operation of the utility-related facility is optimized. 1 ref., 2 figs., 1 tab.

  18. Characterization and modeling of 2D-glass micro-machining by spark-assisted chemical engraving (SACE) with constant velocity

    International Nuclear Information System (INIS)

    Didar, Tohid Fatanat; Dolatabadi, Ali; Wüthrich, Rolf

    2008-01-01

    Spark-assisted chemical engraving (SACE) is an unconventional micro-machining technology based on electrochemical discharge used for micro-machining nonconductive materials. SACE 2D micro-machining with constant speed was used to machine micro-channels in glass. Parameters affecting the quality and geometry of the micro-channels machined by SACE technology with constant velocity were presented and the effect of each of the parameters was assessed. The effect of chemical etching on the geometry of micro-channels under different machining conditions has been studied, and a model is proposed for characterization of the micro-channels as a function of machining voltage and applied speed

  19. Uptake of selenate on hydrated and degraded cement: batch and dynamic experiments

    International Nuclear Information System (INIS)

    Rojo, I.; Rovira, I.; Marti, V.; Pablo, J. de; Duro, L.; Gaona, X.; Colas, E.; Grive, M.

    2009-01-01

    The evaluation of selenate sorption and retardation in batch and dynamic experiments on hydrated and degraded cement has been studied. Desorption studies have also been carried in order to assess the reversibility of the sorption process. Sorption data onto degraded cement have been treated assuming the formation of surface complexes, whereas sorption kinetics has been fitted by using a pseudo-first order kinetic equation. Dynamic flow experiments have also been modelled. (authors)

  20. Improved monitoring of batch processes by incorporating external information

    NARCIS (Netherlands)

    Ramaker, H. J.; van Sprang, E. N. M.; Gurden, S. P.; Westerhuis, J. A.; Smilde, A. K.

    2002-01-01

    In this paper an overview is given of statistical process monitoring with the emphasis on batch processes and the possible steps to take for improving this by incorporating external information. First, the general concept of statistical process monitoring of batches is explained. This concept has

  1. Using warping information for batch process monitoring and fault classification.

    NARCIS (Netherlands)

    González-Martínez, J.M.; Westerhuis, J.A.; Ferrer, A.

    2013-01-01

    This paper discusses how to use the warping information obtained after batch synchronization for process monitoring and fault classification. The warping information can be used for i) building unsupervised control charts or ii) fault classification when a rich faulty batches database is available.

  2. Modelling and Simulation of the Batch Hydrolysis of Acetic ...

    African Journals Online (AJOL)

    The kinetic modelling of the batch synthesis of acetic acid from acetic anhydride was investigated. The kinetic data of the reaction was obtained by conducting the hydrolysis reaction in a batch reactor. A dynamic model was formulated for this process and simulation was carried out using gPROMS® an advanced process ...

  3. Adaptive scheduling of batch servers in flow shops

    NARCIS (Netherlands)

    van der Zee, D.J.

    Batch servicing is a common way of benefiting from economies of scale in manufacturing operations. Good examples of production systems that allow for batch processing are ovens found in the aircraft industry and in semiconductor manufacturing. In this paper we study the issue of dynamic scheduling

  4. Adaptive Scheduling Of Batch Servers In Flow Shops

    NARCIS (Netherlands)

    van der Zee, D.J.

    2001-01-01

    Batch servicing is a common way of benefiting from economies of scale in manufacturing operations. Good examples of production systems that allow for batch processing are ovens found in aircraft industry and in semiconductor manufacturing. In this paper we study the issue of dynamic scheduling of

  5. Solving a chemical batch scheduling problem by local search

    NARCIS (Netherlands)

    Brucker, P.; Hurink, Johann L.

    1999-01-01

    A chemical batch scheduling problem is modelled in two different ways as a discrete optimization problem. Both models are used to solve the batch scheduling problem in a two-phase tabu search procedure. The method is tested on real-world data.

  6. 40 CFR 63.1406 - Reactor batch process vent provisions.

    Science.gov (United States)

    2010-07-01

    ... megagram of product or less for non-solvent-based resin production. (2) The owner or operator of a reactor... 40 Protection of Environment 11 2010-07-01 2010-07-01 true Reactor batch process vent provisions... § 63.1406 Reactor batch process vent provisions. (a) Emission standards. Owners or operators of reactor...

  7. 40 CFR Table 1 to Subpart H of... - Batch Processes

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 9 2010-07-01 2010-07-01 false Batch Processes 1 Table 1 to Subpart H... Subpart H of Part 63—Batch Processes Monitoring Frequency for Equipment Other than Connectors Operating time (% of year) Equivalent continuous process monitoring frequency time in use Monthly Quarterly...

  8. Communication and control in small batch part manufacturing

    NARCIS (Netherlands)

    Tiemersma, J.J.; Curtis, W.; Kals, H.J.J.

    1993-01-01

    This paper reports on the development of a real-time control network as an integrated part of a shop floor control system for small batch part manufacturing. The shop floor control system is called the production control system (PCS). The PCS aims at an improved control of small batch part

  9. On the track of fish batches in three distribution networks

    DEFF Research Database (Denmark)

    Randrup, Maria; Wu, Haiping; Jørgensen, Bo M.

    2012-01-01

    the necessary information, it was possible to locate the end destinations of the fish batches. The batch sizes and the number of companies involved clearly rose when batch joining occurred. Thus, a fault in a small batch can potentially have widespread implications. The study also underlines the importance......Three fish products sampled in retail shops were traced back to their origin and fish from the same batch were tracked forward towards the retailer, thereby simulating a recall situation. The resulting distribution networks were very complex, but to the extent that companies were willing to provide...... of discovering a fault as early as possible in order to minimise the costs of a recall. The localisation of distributed products during a recall operation can be facilitated by a well-constructed traceability system....

  10. Kinetic study of batch and fed-batch enzymatic saccharification of pretreated substrate and subsequent fermentation to ethanol

    Directory of Open Access Journals (Sweden)

    Gupta Rishi

    2012-03-01

    Full Text Available Abstract Background Enzymatic hydrolysis, the rate limiting step in the process development for biofuel, is always hampered by its low sugar concentration. High solid enzymatic saccharification could solve this problem but has several other drawbacks such as low rate of reaction. In the present study we have attempted to enhance the concentration of sugars in enzymatic hydrolysate of delignified Prosopis juliflora, using a fed-batch enzymatic hydrolysis approach. Results The enzymatic hydrolysis was carried out at elevated solid loading up to 20% (w/v and a comparison kinetics of batch and fed-batch enzymatic hydrolysis was carried out using kinetic regimes. Under batch mode, the actual sugar concentration values at 20% initial substrate consistency were found deviated from the predicted values and the maximum sugar concentration obtained was 80.78 g/L. Fed-batch strategy was implemented to enhance the final sugar concentration to 127 g/L. The batch and fed-batch enzymatic hydrolysates were fermented with Saccharomyces cerevisiae and ethanol production of 34.78 g/L and 52.83 g/L, respectively, were achieved. Furthermore, model simulations showed that higher insoluble solids in the feed resulted in both smaller reactor volume and shorter residence time. Conclusion Fed-batch enzymatic hydrolysis is an efficient procedure for enhancing the sugar concentration in the hydrolysate. Restricting the process to suitable kinetic regimes could result in higher conversion rates.

  11. Batch-to-batch quality consistency evaluation of botanical drug products using multivariate statistical analysis of the chromatographic fingerprint.

    Science.gov (United States)

    Xiong, Haoshu; Yu, Lawrence X; Qu, Haibin

    2013-06-01

    Botanical drug products have batch-to-batch quality variability due to botanical raw materials and the current manufacturing process. The rational evaluation and control of product quality consistency are essential to ensure the efficacy and safety. Chromatographic fingerprinting is an important and widely used tool to characterize the chemical composition of botanical drug products. Multivariate statistical analysis has showed its efficacy and applicability in the quality evaluation of many kinds of industrial products. In this paper, the combined use of multivariate statistical analysis and chromatographic fingerprinting is presented here to evaluate batch-to-batch quality consistency of botanical drug products. A typical botanical drug product in China, Shenmai injection, was selected as the example to demonstrate the feasibility of this approach. The high-performance liquid chromatographic fingerprint data of historical batches were collected from a traditional Chinese medicine manufacturing factory. Characteristic peaks were weighted by their variability among production batches. A principal component analysis model was established after outliers were modified or removed. Multivariate (Hotelling T(2) and DModX) control charts were finally successfully applied to evaluate the quality consistency. The results suggest useful applications for a combination of multivariate statistical analysis with chromatographic fingerprinting in batch-to-batch quality consistency evaluation for the manufacture of botanical drug products.

  12. Batch-to-batch learning for model-based control of process systems with application to cooling crystallization

    NARCIS (Netherlands)

    Forgione, M.

    2014-01-01

    From an engineering perspective, the term process refers to a conversion of raw materials into intermediate or final products using chemical, physical, or biological operations. Industrial processes can be performed either in continuous or in batch mode. There exist for instance continuous and batch

  13. Glucoamylase production in batch, chemostat and fed-batch cultivations by an industrial strain of Aspergillus niger

    DEFF Research Database (Denmark)

    Pedersen, Henrik; Beyer, Michael; Nielsen, Jens

    2000-01-01

    The Aspergillus niger strain BO-1 was grown in batch, continuous (chemostat) and fed-batch cultivations in order to study the production of the extracellular enzyme glucoamylase under different growth conditions. In the pH range 2.5-6.0, the specific glucoamylase productivity and the specific...

  14. Modeling and Design of Capacitive Micromachined Ultrasonic Transducers Based-on Database Optimization

    International Nuclear Information System (INIS)

    Chang, M W; Gwo, T J; Deng, T M; Chang, H C

    2006-01-01

    A Capacitive Micromachined Ultrasonic Transducers simulation database, based on electromechanical coupling theory, has been fully developed for versatile capacitive microtransducer design and analysis. Both arithmetic and graphic configurations are used to find optimal parameters based on serial coupling simulations. The key modeling parameters identified can improve microtransducer's character and reliability effectively. This method could be used to reduce design time and fabrication cost, eliminating trial-and-error procedures. Various microtransducers, with optimized characteristics, can be developed economically using the developed database. A simulation to design an ultrasonic microtransducer is completed as an executed example. The dependent relationship between membrane geometry, vibration displacement and output response is demonstrated. The electromechanical coupling effects, mechanical impedance and frequency response are also taken into consideration for optimal microstructures. The microdevice parameters with the best output signal response are predicted, and microfabrication processing constraints and realities are also taken into consideration

  15. Study on vacuum packaging reliability of micromachined quartz tuning fork gyroscopes

    Science.gov (United States)

    Fan, Maoyan; Zhang, Lifang

    2017-09-01

    Packaging technology of the micromachined quartz tuning fork gyroscopes by vacuum welding has been experimentally studied. The performance of quartz tuning fork is influenced by the encapsulation shell, encapsulation method and fixation of forks. Alloy solder thick film is widely used in the package to avoid the damage of the chip structure by the heat resistance and hot temperature, and this can improve the device performance and welding reliability. The results show that the bases and the lids plated with gold and nickel can significantly improve the airtightness and reliability of the vacuum package. Vacuum packaging is an effective method to reduce the vibration damping, improve the quality factor and further enhance the performance. The threshold can be improved nearly by 10 times.

  16. Double-section curvature tunable functional actuator with micromachined buckle and grid wire for electricity delivery

    International Nuclear Information System (INIS)

    Feng, Guo-Hua; Hou, Sheng-You

    2015-01-01

    This paper presents an ionic polymer metal composite (IPMC)-driven tentacle-like biocompatible flexible actuator with double-section curvature tunability. This actuator, possessing an embedded electrical transmission ability that mimics skeletal muscle nerves in the human body, affords versatile device functions. Novel micromachined copper buckles and grid wires are fabricated and their superiority in electricity delivery and driving the IPMC component with less flexural rigidity is demonstrated. In addition, soft conductive wires realized on a polydimethylsiloxane structure function as electrical signal transmitters. A light-emitting diode integrated with the developed actuator offers directional guiding light ability while the actuator performs a snake-like motion. The electrical conductivity and Young’s modulus of the key actuator components are investigated, and flexural rigidity and dynamic behavior analyses of the actuator under electrical manipulation are elaborated. (paper)

  17. Double-section curvature tunable functional actuator with micromachined buckle and grid wire for electricity delivery

    Science.gov (United States)

    Feng, Guo-Hua; Hou, Sheng-You

    2015-09-01

    This paper presents an ionic polymer metal composite (IPMC)-driven tentacle-like biocompatible flexible actuator with double-section curvature tunability. This actuator, possessing an embedded electrical transmission ability that mimics skeletal muscle nerves in the human body, affords versatile device functions. Novel micromachined copper buckles and grid wires are fabricated and their superiority in electricity delivery and driving the IPMC component with less flexural rigidity is demonstrated. In addition, soft conductive wires realized on a polydimethylsiloxane structure function as electrical signal transmitters. A light-emitting diode integrated with the developed actuator offers directional guiding light ability while the actuator performs a snake-like motion. The electrical conductivity and Young’s modulus of the key actuator components are investigated, and flexural rigidity and dynamic behavior analyses of the actuator under electrical manipulation are elaborated.

  18. Development of Capacitive Micromachined Ultrasonic Transducer (I) - Analysis of the Membrane Behavior

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ki Bok; Ahn, Bong Young; Park, Hae Won; Kim, Young Joo; Lee, Seung Seok [Korea Research Institute of Standards and Science, Daejeon (Korea, Republic of)

    2004-10-15

    This study was conducted to develop a capacitive micromachined ultrasonic transducer (cMUT) which enable to high efficient non-contact transmit and receive the ultrasonic wave in air. Theoretical analysis and finite element analysis of the behavior of membrane (such as resonance frequency, membrane deflection, collapse deflection and collapse voltage) of the cMUT were performed. The design parameters of the cMUT such as the dimension and thickness of membrane, thickness of sacrificial layer, thickness and size of electrode were estimated. The resonance frequency of the membrane increased as the thickness of the membrane increased but decreased as the diameter of the membrane increased. The deflection of the membrane increased as d-c bias voltage increased. The collapse voltage of the membrane was analyzed

  19. Modeling and analysis of the membrane-behavior in capacitive micromachined ultrasonic transducer

    International Nuclear Information System (INIS)

    Kim, Ki Bok; Ahn, Bong Young; Park, Hae Won; Kim, Young Joo; Kim, Kuk Jin; Lee, Seung Seok

    2003-01-01

    In this study, theoretical analysis and finite element analysis of the behavior of membrane (such as resonance frequency, membrane deflection, collapse deflection and collapse voltage) in the capacitive micromachined ultrasonic transducer (cMUT) were performed. The design parameters of the cMUT were estimated and are the dimension and thickness of membrane, thickness of sacrificial layer, thickness and size of electrode, size of active element and so on. The resonance frequency of the membrane increased as the thickness of the membrane increased but decreased as the diameter of the membrane increased. The deflection of the membrane increased as d-c bias voltage increased. The collapse voltage of the membrane was predicted.

  20. Low temperature capacitive micromachined ultrasonic transducers (cMUTs) on glass substrate

    International Nuclear Information System (INIS)

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

    2016-01-01

    The possibility of fabricating capacitive micromachined ultrasonic transducers (cMUTs) on glass substrates may open the way for new fields of application in which the transparency of the substrate is advantageous. In this study, we demonstrate that a low-temperature process can be carried out to achieve cMUTs on glass substrates. Limited to temperatures lower than 400 °C, the process is based on the use of nickel as a sacrificial layer. The cMUT electromechanical behavior is studied and the performance compared to those obtained with silicon substrates. The cMUTs fabricated on glass substrate showed performance comparable with the Si ones. A slight shift in the resonance frequency and collapse voltage was observed. It is shown that these differences arise from the residual mechanical stresses in the substrate. (paper)

  1. Modeling and analysis of the membrane-behavior in capacitive micromachined ultrasonic transducer

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ki Bok; Ahn, Bong Young; Park, Hae Won; Kim, Young Joo; Kim, Kuk Jin; Lee, Seung Seok [NDE Group, Korea Research Institute of Standards and Science, Daejeon (Korea, Republic of)

    2003-05-15

    In this study, theoretical analysis and finite element analysis of the behavior of membrane (such as resonance frequency, membrane deflection, collapse deflection and collapse voltage) in the capacitive micromachined ultrasonic transducer (cMUT) were performed. The design parameters of the cMUT were estimated and are the dimension and thickness of membrane, thickness of sacrificial layer, thickness and size of electrode, size of active element and so on. The resonance frequency of the membrane increased as the thickness of the membrane increased but decreased as the diameter of the membrane increased. The deflection of the membrane increased as d-c bias voltage increased. The collapse voltage of the membrane was predicted.

  2. Modeling and analysis of the membrane-behavior in capacitive micromachined ultrasonic transducer

    International Nuclear Information System (INIS)

    Kim, Ki Bok; Ahn, Bong Young; Park, Hae Won; Kim, Young Joo; Kim, Kuk Jin; Lee, Seung Seok

    2003-01-01

    In this study, theoretical analysis and finite element analysis of the behavior of membrane (such as resonance frequency, membrane deflection, collapse deflection and collapse voltage) in the capacitive micromachined ultrasonic transducer (cMUT) were performed. The design parameter of the cMUT were estimated and are the dimension and thickness of membrane, thickness of sacrificed layer, thickness and size of electrode, size of active element and so on. The resonance frequency of the membrane increased as the thickness of the membrane increased but decreased as the diameter of the membrane increased. The deflection of the membrane increased as d-c bias voltage increased. The collapse voltage of the membrane was predicted.

  3. Low temperature capacitive micromachined ultrasonic transducers (cMUTs) on glass substrate

    Science.gov (United States)

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

    2016-11-01

    The possibility of fabricating capacitive micromachined ultrasonic transducers (cMUTs) on glass substrates may open the way for new fields of application in which the transparency of the substrate is advantageous. In this study, we demonstrate that a low-temperature process can be carried out to achieve cMUTs on glass substrates. Limited to temperatures lower than 400 °C, the process is based on the use of nickel as a sacrificial layer. The cMUT electromechanical behavior is studied and the performance compared to those obtained with silicon substrates. The cMUTs fabricated on glass substrate showed performance comparable with the Si ones. A slight shift in the resonance frequency and collapse voltage was observed. It is shown that these differences arise from the residual mechanical stresses in the substrate.

  4. Development of Capacitive Micromachined Ultrasonic Transducer (I) - Analysis of the Membrane Behavior

    International Nuclear Information System (INIS)

    Kim, Ki Bok; Ahn, Bong Young; Park, Hae Won; Kim, Young Joo; Lee, Seung Seok

    2004-01-01

    This study was conducted to develop a capacitive micromachined ultrasonic transducer (cMUT) which enable to high efficient non-contact transmit and receive the ultrasonic wave in air. Theoretical analysis and finite element analysis of the behavior of membrane (such as resonance frequency, membrane deflection, collapse deflection and collapse voltage) of the cMUT were performed. The design parameters of the cMUT such as the dimension and thickness of membrane, thickness of sacrificial layer, thickness and size of electrode were estimated. The resonance frequency of the membrane increased as the thickness of the membrane increased but decreased as the diameter of the membrane increased. The deflection of the membrane increased as d-c bias voltage increased. The collapse voltage of the membrane was analyzed

  5. 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.

  6. Finite Element Analysis of Capacitive Micromachined Ultrasonic Transducer (CMUT) for NDE Applications

    Science.gov (United States)

    Singh, Manvinder; Kommareddy, Vamshi; Kumar, Manoj; Ramaswamy, Sivaramanivas; Fan, Ying; Barshinger, James; Tian, Wei-Cheng; Kishore, Kuna

    2006-03-01

    This paper presents a comparison of three Finite Element approaches for modeling the behavior of a Capacitive Micromachined Ultrasonic Transducer (CMUT). CMUTs have become very popular over the last decade because of the comparable bandwidth, sensitivity and dynamic range with its piezoelectric counterparts. The ease of fabrication is an added advantage. Modeling of CMUTs is a coupled physics problem, which involves solving Electrostatics and Structural interactions simultaneous. Finite Element models of the CMUT are constructed using the commercial code ANSYS (9.0). Three different approaches of solving the coupled field problem are discussed and the results are compared for resonance frequency, collapse voltage, capacitance and electromechanical coupling coefficient. The approaches discussed involve sequentially coupled-field analysis, direct coupled-field analysis and reduced order modeling. Detailed results have been presented for the effect of variation in geometrical factors as predicted by the three models.

  7. The influence of acoustic damping on the transformation efficiency of capacitive micromachined ultrasonic transducer in air

    Science.gov (United States)

    Lee, Seung-Mok; Cha, Bu-sang; Okuyama, Masanori

    2010-10-01

    Acoustic damping of a capacitive micromachined ultrasonic transducer (CMUT) in air causes mechanical impedance to the membrane vibration, which significantly influences the transformation efficiency of the device. We observed the effect of acoustic damping on the transformation efficiency of a CMUT under various external acoustic pressure and device structure conditions; the results were compared with other factors such as capacitance variations originating from the change in air-hole rate [area ratio (AR)] over the total membrane area. The damping ratio of the perforated membrane plate was computed for each acoustic pressure condition, and the results were introduced into calculations of the membrane displacement using the finite element method to take the squeeze-film damping effect into account. The Q factor and transformation efficiency of the CMUT under various AR for the membrane and dimension conditions of the device were studied; the acoustic damping effect is discussed in terms of design optimization.

  8. Deep Tissue Photoacoustic Imaging Using a Miniaturized 2-D Capacitive Micromachined Ultrasonic Transducer Array

    Science.gov (United States)

    Kothapalli, Sri-Rajasekhar; Ma, Te-Jen; Vaithilingam, Srikant; Oralkan, Ömer

    2014-01-01

    In this paper, we demonstrate 3-D photoacoustic imaging (PAI) of light absorbing objects embedded as deep as 5 cm inside strong optically scattering phantoms using a miniaturized (4 mm × 4 mm × 500 µm), 2-D capacitive micromachined ultrasonic transducer (CMUT) array of 16 × 16 elements with a center frequency of 5.5 MHz. Two-dimensional tomographic images and 3-D volumetric images of the objects placed at different depths are presented. In addition, we studied the sensitivity of CMUT-based PAI to the concentration of indocyanine green dye at 5 cm depth inside the phantom. Under optimized experimental conditions, the objects at 5 cm depth can be imaged with SNR of about 35 dB and a spatial resolution of approximately 500 µm. Results demonstrate that CMUTs with integrated front-end amplifier circuits are an attractive choice for achieving relatively high depth sensitivity for PAI. PMID:22249594

  9. Modeling and analysis of the membrane-behavior in capacitive micromachined ultrasonic transducer

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ki Bok; Ahn, Bong Young; Park, Hae Won; Kim, Young Joo; Kim, Kuk Jin; Lee, Seung Seok [Korea Research Institute of Standards and Science, Daejeon (Korea, Republic of)

    2003-07-01

    In this study, theoretical analysis and finite element analysis of the behavior of membrane (such as resonance frequency, membrane deflection, collapse deflection and collapse voltage) in the capacitive micromachined ultrasonic transducer (cMUT) were performed. The design parameter of the cMUT were estimated and are the dimension and thickness of membrane, thickness of sacrificed layer, thickness and size of electrode, size of active element and so on. The resonance frequency of the membrane increased as the thickness of the membrane increased but decreased as the diameter of the membrane increased. The deflection of the membrane increased as d-c bias voltage increased. The collapse voltage of the membrane was predicted.

  10. Monolithic integration of micromachined sensors and CMOS circuits based on SOI technologies

    International Nuclear Information System (INIS)

    Yu Xiaomei; Tang Yaquan; Zhang Haitao

    2008-01-01

    This note presents a novel way to monolithically integrate micro-cantilever sensors and signal conditioning circuits by combining SOI CMOS and SOI micromachining technologies. In order to improve the sensor performance and reduce the system volume, an integrated sensor system composed of a piezoresistive cantilever array, a temperature-compensation current reference, a digitally controlled multiplexer and an instrument amplifier is designed and finally fabricated. A post-SOI CMOS process is developed to realize the integrated sensor system which is based on a standard CMOS process with one more mask to define the cantilever structure at the end of the process. Measurements on the finished SOI CMOS devices and circuits show that the integration process has good compatibility both for the cantilever sensors and for the CMOS circuits, and the SOI CMOS integration process can decrease about 25% sequences compared with the bulk silicon CMOS process. (note)

  11. Micro-machinable polymer-derived ceramic sensors for high-temperature applications

    Science.gov (United States)

    Liu, Jian; Xu, Chengying; An, Linan

    2010-04-01

    Micro-sensors are highly desired for on-line temperature/pressure monitoring in turbine engines to improve their efficiency and reduce pollution. The biggest challenge for developing this type of sensors is that the sensors have to sustain at extreme environments in turbine engine environments, such as high-temperatures (>800 °C), fluctuated pressure and oxidation/corrosion surroundings. In this paper, we describe a class of sensors made of polymer-derived ceramics (PDCs) for such applications. PDCs have the following advantages over conventional ceramics, making them particularly suitable for these applications: (i) micromachining capability, (ii) tunable electric properties, and (iii) hightemperature capability. Here, we will discuss the materials and their properties in terms of their applications for hightemperature micro-sensors, and microfabrication technologies. In addition, we will also discuss the design of a heat-flux sensor based on polymer-derived ceramics.

  12. Corporate array of micromachined dipoles on silicon wafer for 60 GHz communication systems

    KAUST Repository

    Sallam, M. O.

    2013-03-01

    In this paper, an antenna array operating at 60 GHz and realized on 0.675 mm thick silicon substrate is presented. The array is constructed using four micromachined half-wavelength dipoles fed by a corporate feeding network. Isolation between the antenna array and its feeding network is achieved via a ground plane. This arrangement leads to maximizing the broadside radiation with relatively high front-to-back ratio. Simulations have been carried out using both HFSS and CST, which showed very good agreement. Results reveal that the proposed antenna array has good radiation characteristics, where the directivity, gain, and radiation efficiency are around 10.5 dBi, 9.5 dBi, and 79%, respectively. © 2013 IEEE.

  13. Multifrequency Excitation Method for Rapid and Accurate Dynamic Test of Micromachined Gyroscope Chips

    Directory of Open Access Journals (Sweden)

    Yan Deng

    2014-10-01

    Full Text Available A novel multifrequency excitation (MFE method is proposed to realize rapid and accurate dynamic testing of micromachined gyroscope chips. Compared with the traditional sweep-frequency excitation (SFE method, the computational time for testing one chip under four modes at a 1-Hz frequency resolution and 600-Hz bandwidth was dramatically reduced from 10 min to 6 s. A multifrequency signal with an equal amplitude and initial linear-phase-difference distribution was generated to ensure test repeatability and accuracy. The current test system based on LabVIEW using the SFE method was modified to use the MFE method without any hardware changes. The experimental results verified that the MFE method can be an ideal solution for large-scale dynamic testing of gyroscope chips and gyroscopes.

  14. Bending-induced electromechanical coupling and large piezoelectric response in a micromachined diaphragm

    KAUST Repository

    Wang, Zhihong

    2013-11-04

    We investigated the dependence of electromechanical coupling and the piezoelectric response of a micromachined Pb(Zr 0.52 Ti 0.48)O 3 (PZT) diaphragm on its curvature by observing the impedance spectrum and central deflection responses to a small AC voltage. The curvature of the diaphragm was controlled by applying air pressure to its back. We found that a depolarized flat diaphragm does not initially exhibit electromechanical coupling or the piezoelectric response. However, upon the application of static air pressure to the diaphragm, both electromechanical coupling and the piezoelectric response can be induced in the originally depolarized diaphragm. The piezoelectric response increases as the curvature increases and a giant piezoelectric response can be obtained from a bent diaphragm. The obtained results clearly demonstrate that a high strain gradient in a diaphragm can polarize a PZT film through a flexoelectric effect, and that the induced piezoelectric response of the diaphragm can be controlled by adjusting its curvature.

  15. High efficiency on-chip Dielectric Resonator Antennna using micromachining technology

    KAUST Repository

    Sallam, Mai O.

    2015-10-26

    In this paper, a novel cylindrical Dielectric Resonator Antenna (DRA) operating at 60 GHz is introduced. The antenna is fabricated using a high-resistivity silicon wafer. The DR is defined in the wafer using micromachining technology. The feeding network is located at the other side of the wafer. The proposed antenna is simulated using HFSS and the results are verified by measurements. The antenna radiation is mainly along the broadside direction. The measured gain, radiation efficiency, and bandwidth are 7 dBi, 74.65%, and 2.23 GHz respectively. The antenna is characterized by high polarization purity where the maximum cross-polarization is -15 dB. © 2015 IEEE.

  16. CLASP (Capture and Locking alignment Spring Positioner): A micromachined fiber auto-positioning device

    Energy Technology Data Exchange (ETDEWEB)

    Kravitz, S.H.; word, J.C.; Bauer, T.M.; Seigal, P.K.; Armendariz, M.G.

    1996-03-01

    This work provides a method of mechanical alignment of an array of single mode fibers to an array of optical devices. The technique uses a micromachined metal spring, which captures a vertical, pre- positioned fiber, moves it into accurate alignment, and holds it for attachment. The spring is fabricated from electroplated mickel, using photodefined polyimide as a plating mask. The nickel is plated about 80 {mu}m thick, so that a large fiber depth is captured. In one application, the nickel springs can be aligned to optics on the back side of the substrate. This entire concept is referred to as CLASP (Capture and Locking Alignment Spring Positioner). These springs can be used for general alignment and capture of any fiber to any optical input or output device. Passive alignment of fiber arrays to {plus}/{minus} 2{mu}m accuracy has been demonstrated, with a clear path to improved accuracy.

  17. Micromachined On-Chip Dielectric Resonator Antenna Operating at 60 GHz

    KAUST Repository

    Sallam, Mai

    2015-06-01

    This paper presents a novel cylindrical Dielectric Resonator Antenna (DRA) suitable for millimeter-wave on-chip systems. The antenna was fabricated from a single high resistivity silicon wafer via micromachining technology. The new antenna was characterized using HFSS and experimentally with good agreement been found between the simulations and experiment. The proposed DRA has good radiation characteristics, where its gain and radiation efficiency are 7 dBi and 79.35%, respectively. These properties are reasonably constant over the working frequency bandwidth of the antenna. The return loss bandwidth was 2.23 GHz, which corresponds to 3.78% around 60 GHz. The antenna was primarily a broadside radiator with -15 dB cross polarization level.

  18. Micromachining. CERN Courier, Jul-Aug 1995, v. 35(5)

    International Nuclear Information System (INIS)

    Wilson, Martin

    1995-01-01

    Full text: As well as making microcircuit components, X-ray lithography can also be used to make very small mechanical parts, either by using directly the exposed and developed photoresist, or as a mould to produce the component in another material such as ceramic or metal. In this revolutionary technology, metal components are made via the LIGA (Lithographic Galvanoformung und Abformung) technique in which the exposed and developed photoresist is coated with a conducting material and then electroplated, after which the resist is stripped away. In addition to fine size and precision resolution, X-rays offer the advantage of deep penetration and small scattering through the resist, so that patterns may be up to a millimetre deep, with very accurate straightness in directions parallel to the beam. Micromachining via LIGA was developed at KfK Karlsruhe; commercialization and further development is being vigorously pursued by the Institut fur Mikrotechnik in Mainz and by Microparts GmbH in Karlsruhe. Significant developments have been made at the Synchrotron Radiation Centre in Madison, Wisconsin, with new programmes start-ing at SRRC (Taiwan), CAMD (Baton Rouge, Louisiana), and LURE (Paris). There is now an active European Special Interest Group for LIGA. Commercially manufactured micromachines are starting to be used in sensors and connectors. The ability to integrate microdevices with microelectronics raises many interesting possibilities for the future, notably in medicine and for intelligent sensors. In all cases, however, widespread adoption will be governed by the ability to mass-produce cheaply, requiring high volume production. The high intensities of synchrotron radiation will assist in achieving these large throughputs

  19. 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

  20. Batch and fed-batch production of butyric acid by Clostridium butyricum ZJUCB

    OpenAIRE

    He, Guo-qing; Kong, Qing; Chen, Qi-he; Ruan, Hui

    2005-01-01

    The production of butyric acid by Clostridium butyricum ZJUCB at various pH values was investigated. In order to study the effect of pH on cell growth, butyric acid biosynthesis and reducing sugar consumption, different cultivation pH values ranging from 6.0 to 7.5 were evaluated in 5-L bioreactor. In controlled pH batch fermentation, the optimum pH for cell growth and butyric acid production was 6.5 with a cell yield of 3.65 g/L and butyric acid yield of 12.25 g/L. Based on these results, th...

  1. Design and construction of a batch oven for investigation of industrial continuous baking processes

    DEFF Research Database (Denmark)

    Stenby Andresen, Mette; Risum, Jørgen; Adler-Nissen, Jens

    2013-01-01

    A new batch oven has been constructed to mimic industrial convection tunnel ovens for research and development of continuous baking processes. The process parameters (air flow, air temperature, air humidity, height of baking area and the baking band velocity) are therefore highly controllable...... and adjustable over a wide range of settings. It is possible to monitor the product weight and temperature continuously during baking. The simultaneous measuring of mass and a window allowing for visual (e.g., by video recording) control is unique for this experimental batch oven. Two validation steps have been...... oven, with a butter cookie as the test product. The investigated quality parameters for the butter cookies were mass loss and surface browning, where the uniformity of browning was evaluated subjectively against a scale of standards and objectively by L* value measurements. Good reproducibility...

  2. FY 1994 Report on the technical results. Research and development of micromachine technologies (Development of highly functional maintenance technologies for power plants); 1994 nendo micromachine gijutsu no kenkyu kaihatsu seika hokokusho. Hatsuden shisetsuyo kokino maintenance gijutsu kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-09-01

    This research and development project is aimed at development of the technologies for the micromachines provided with maintenance functions, e.g., for examination and maintenance of abnormal conditions in heat exchangers, piping systems or the like. The initial target is set at establishment of basic technologies for the micromachines, in consideration of the available technologies. The R and D activities are directed to (1) microcapsules for, e.g., micro power generators, (2) mother machines having controlling and instructing functions, (3) non-cabled examination modules, (4) cabled examination modules, and (5) total systems. The item (1) involves the micro power generators, and mechanisms of signal transmission, flaw finding and driving/suspension; the item (2) mechanisms of micro-optics and connection, group controlling, microbatteries, action type controlling, and artificial muscles; the item (3) expansion/contraction type transfer mechanisms, light energy supply, micro visual sensation, function connection, and concerted controlling; the item (4) tubular manipulators, and mechanisms of light-aided power generation and voltage elevation; and the item (5) maintenance and micromachine systems. (NEDO)

  3. Simulation of the Mitra 15 micro-machine on IBM 360/91. Microprogramming of the fast Fourier transform

    International Nuclear Information System (INIS)

    Augustides, Jean

    1973-01-01

    As computing time did not allow working in real time, and as different methods had been proposed to reduce the computing time (the Cooley-Tuckey method, the use of specific FFT processors), this thesis proposes an intermediate solution, between the entirely programmed solution and the entirely cabled solution. After some generalities on micro-programming (definition, history, benefits and drawbacks, perspectives), the author reports the micro-programming of the Mitra 15 micro-machine: description of the machine, memory, command memory and associated circuits, interruptions and suspensions, descriptions of micro-statements, execution of a micro-statement. Programs and subroutines developed for the modelling of Mitra 15 micro-machine on IBM 360/91 are presented. Then, the author reports the micro-programming of the fast Fourier transform: theory, program description, and test

  4. 40 CFR 63.462 - Batch cold cleaning machine standards.

    Science.gov (United States)

    2010-07-01

    .... (a) Each owner or operator of an immersion batch cold solvent cleaning machine shall comply with the... cleaning machine complying with paragraph (a)(2) or (b) of this section shall comply with the work and...

  5. Numerical modeling of batch formation in waste incineration plants

    Directory of Open Access Journals (Sweden)

    Obroučka Karel

    2015-03-01

    Full Text Available The aim of this paper is a mathematical description of algorithm for controlled assembly of incinerated batch of waste. The basis for formation of batch is selected parameters of incinerated waste as its calorific value or content of pollutants or the combination of both. The numerical model will allow, based on selected criteria, to compile batch of wastes which continuously follows the previous batch, which is a prerequisite for optimized operation of incinerator. The model was prepared as for waste storage in containers, as well as for waste storage in continuously refilled boxes. The mathematical model was developed into the computer program and its functionality was verified either by practical measurements or by numerical simulations. The proposed model can be used in incinerators for hazardous and municipal waste.

  6. Micromachining of Al2O3-TiC ceramics by excimer laser

    Directory of Open Access Journals (Sweden)

    Oliveira, V.

    1998-04-01

    Full Text Available Micromachining of Al2O3-TiC ceramic using a KrF excimer laser was studied in the fluence range 2 to 8 J/cm2 . The ablation rate decreases and the roughness increases with the first pulses but after about 200 pulses the process reaches a stationary stage where both roughness and ablation rate become constant. Observation of the processed areas by scanning electron microscopy showed that a globular topography is formed during the first stage and that the surface topography remains unchanged with further pulses. This globular topography is responsible for the variation of roughness and ablation rate observed during the first stage. EDS analysis showed that the globular features present an external region with higher titanium content and a core formed of unaffected material.

    Se estudia el micromecanizado de cerámicas Al2O3-TiC mediante un láser de excímero de KrF con un rango de fluencia de 2 a 8 J/cm2 . La velocidad de ablación disminuye y la rugosidad aumenta con los primeros pulsos. Sin embargo, después de 200 pulsos, el proceso alcanza el régimen estacionario, donde tanto la rugosidad como la velocidad de ablación permanecen constantes. La observación mediante SEM de determinadas áreas mostraban una topografía globular formada durante la primera etapa, mientras que con los siguientes pulsos permanece in cambios. Esta topografía globular es responsable de la variación de rugosidad y de la velocidad de ablación observada durante las primeras etapas del proceso. Los análisis de EDS sobre las zonas globulares mostraron la existencia de una región externa rica en titanio y un núcleo formado por el material sin afectar.

  7. Evaluation of sequencing batch reactor performance for petrochemical wastewater treatment

    OpenAIRE

    Mina Salari; Seyed Ahmad Ataei; Fereshteh Bakhtiyari

    2017-01-01

    Sequencing batch reactor (SBR) technology has found many applications in industrial wastewater treatment in recent years. The aim of this study was to determine the optimal time for a cycle of the sequencing batch reactor (SBR) and evaluate the performance of a SBR for petrochemical wastewater treatment in that cycle time. The reactor was operated with a suspended biomass configuration under aerobic conditions. Carbon removal and operating parameters such as pH, temperature and dissolved oxyg...

  8. BACKGROUND AND PROSPECTS FOR THE OPERATION OF BATCH DISTILLATION

    OpenAIRE

    Lombira Echevarria, J.; Universidad Nacional Mayor de San Marcos, Facultad de Química e Ingeniería Química Unidad de Post Grado, Av . Venezuela s/n Lima -Perú; Otiniano Cáceres, M.; Universidad Naciona l Mayor de San Marcos, Facultad de Química e Ingeniería Química Unidad de Post Grado, Av . Venezuela s/n Lima -Perú

    2014-01-01

    Present contribution constitutes a review that shows the results of bibliographic research carried out about the simulation, design and optimization of batch. Distillation operation. It is analyses the present state of the art of this operation, contrasting its recent achieved results with difficulties that still exist in this area. The different batch distillation columns configurations that have been developed recently, such as the inverted column , middle vessels, multiple effects , extrac...

  9. Extracellular production of a glycolipid biosurfactant, mannosylerythritol lipid, by Candida sp. SY16 using fed-batch fermentation.

    Science.gov (United States)

    Kim, Hee-Sik; Jeon, Jong-Woon; Kim, Byung-Hyuk; Ahn, Chi-Yong; Oh, Hee-Mock; Yoon, Byung-Dae

    2006-04-01

    Candida sp. strain SY16 produces a glycolipid-type biosurfactant, mannosylerythritol lipid (MEL-SY16), which can reduce the surface tension of a culture broth from 72 to 30 dyne cm(-1) and highly emulsify hydrocarbons when cultured in soybean-oil-containing media. As such, laboratory-scale fermentation for MEL-SY16 production was performed using optimized conditions. In batch fermentation, MEL-SY16 was mainly produced during the stationary phase of growth, and the concentration of MEL-SY16 reached 37 g l(-1) after 200 h. The effect of pH control on the production of MEL-SY16 was also examined in batch fermentation. The highest production yield of MEL-SY16 was when the pH was controlled at 4.0, and the production was significantly improved compared to batch fermentation without pH control. In fed-batch fermentation, glucose and soybean oil (1:1, w/w) were used in combination as the initial carbon sources for cell growth, and soybean oil was used as the feeding carbon source during the MEL production phase. The feeding of soybean oil resulted in the disappearance of any foam and a sharp increase in the MEL production until 200 h, at which point the concentration of MEL-SY16 was 95 g l(-1). Among the investigated culture systems, the highest MEL-SY16 production and volumetric production rate were achieved with fed-batch fermentation.

  10. Polynomial Batch Codes for Efficient IT-PIR

    Directory of Open Access Journals (Sweden)

    Henry Ryan

    2016-10-01

    Full Text Available Private information retrieval (PIR is a way for clients to query a remote database without the database holder learning the clients’ query terms or the responses they generate. Compelling applications for PIR are abound in the cryptographic and privacy research literature, yet existing PIR techniques are notoriously inefficient. Consequently, no such PIRbased application to date has seen real-world at-scale deployment. This paper proposes new “batch coding” techniques to help address PIR’s efficiency problem. The new techniques exploit the connection between ramp secret sharing schemes and efficient information-theoretically secure PIR (IT-PIR protocols. This connection was previously observed by Henry, Huang, and Goldberg (NDSS 2013, who used ramp schemes to construct efficient “batch queries” with which clients can fetch several database records for the same cost as fetching a single record using a standard, non-batch query. The new techniques in this paper generalize and extend those of Henry et al. to construct “batch codes” with which clients can fetch several records for only a fraction the cost of fetching a single record using a standard non-batch query over an unencoded database. The batch codes are highly tuneable, providing a means to trade off (i lower server-side computation cost, (ii lower server-side storage cost, and/or (iii lower uni- or bi-directional communication cost, in exchange for a comparatively modest decrease in resilience to Byzantine database servers.

  11. Analysis of the current density characteristics in through-mask electrochemical micromachining (TMEMM for fabrication of micro-hole arrays on invar alloy film

    Directory of Open Access Journals (Sweden)

    Da-som JIN

    2017-06-01

    Full Text Available Invar alloy consisting of 64% iron and 36% nickel has been widely used for the production of shadow masks for organic light emitting diodes (OLEDs because of its low thermal expansion coefficient (1.86 × 10−6 cm/°C. To fabricate micro-hole arrays on 30 μm invar alloy film, through-mask electrochemical micromachining (TMEMM was developed and combined with a portion of the photolithography etching process. For precise hole shapes, patterned photoresist (PR film was applied as an insulating mask. To investigate the relationship between the current density and the material removal rate, the principle of the electrochemical machining was studied with a focus on the equation. The finite element method (FEM was used to verify the influence of each parameter on the current density on the invar alloy film surface. The parameters considered were the thickness of the PR mask, inter-electrode gap (IEG, and electrolyte concentration. Design of experiments (DOE was used to figure out the contribution of each parameter. A simulation was conducted with varying parameters to figure out their relationships with the current density. Optimization was conducted to select the suitable conditions. An experiment was carried out to verify the simulation results. It was possible to fabricate micro-hole arrays on invar alloy film using TMEMM, which is a promising method that can be applied to fabrications of OLEDs shadow masks.

  12. Ultrawide continuously tunable 1.55-μm vertical air-cavity wavelength-selective elements for VCSELs using micromachined electrostatic actuation

    Science.gov (United States)

    Hillmer, Hartmut H.; Daleiden, Juergen; Prott, Cornelia; Roemer, Friedhard; Irmer, Soeren; Ataro, Edwin; Tarraf, Amer; Gutermuth, D.; Kommallein, I.; Strassner, Martin

    2003-08-01

    Surface-micromachined 1.55μm vertical-resonator-based devices, capable of wide, continuous, monotonic and kink-free tuning are designed, technologically implemented and characterized. Tuning is achieved by mechanically actuating one or several membranes in a vertical resonator including two ultra-highly reflective DBR mirrors. The tuning is controlled by a single parameter (actuation voltage). The two different layers composing the mirrors reveal a very strong refractive index contrast. Filters including InP/air-gap DBR's (3.5 periods) using GaInAs sacrificial layers reveal a continuous tuning of up to 9% of the absolute wavelength. Varying a reverse voltage (U=0 .. -3.2V) between the membranes, a tuning range up to 142nm was obtained by electrostatic actuation. The correlation of the wavelength and the applied voltage is accurately reproducible without any hysteresis. Theoretical model calculations are performed for symmetric and asymmetric device structures, varying layer thickness and compositions. Models of highly sophisticated color tuning can be found in nature, e.g. in tunable spectral light filtering by trogon and butterfly wings. Bionics transfers the principles of success of nature into natural science, engineering disciplines and applications (here filters and VCSELs for optical communication on the basis of WDM). Light interferes constructively and destructively with nano- and microstructures of appropriate shape, dimensions and materials, both in the artificial DBR structures fabricated in our labs as well as in the natural ones.

  13. Batch-to-Batch Quality Consistency Evaluation of Botanical Drug Products Using Multivariate Statistical Analysis of the Chromatographic Fingerprint

    OpenAIRE

    Xiong, Haoshu; Yu, Lawrence X.; Qu, Haibin

    2013-01-01

    Botanical drug products have batch-to-batch quality variability due to botanical raw materials and the current manufacturing process. The rational evaluation and control of product quality consistency are essential to ensure the efficacy and safety. Chromatographic fingerprinting is an important and widely used tool to characterize the chemical composition of botanical drug products. Multivariate statistical analysis has showed its efficacy and applicability in the quality evaluation of many ...

  14. Use of batch and column methodologies to assess utility waste leaching and subsurface chemical attenuation

    International Nuclear Information System (INIS)

    Zachara, J.M.; Streile, G.P.

    1991-05-01

    Waste leaching and chemical attenuation involve geochemical reactions between immobile solid surfaces in the waste or in other porous media and dissolved solutes in the mobile fluid phase. Because the geochemical reactions occur along with water flow, the question often arises whether waste leaching and chemical attenuation are best studied under static or dynamic conditions. To answer this question, the scientific literature was reviewed to identify how static (batch) and dynamic (column) approaches have been applied to obtain data on waste leaching and chemical attenuation and the types of information each technique has provided. This review made it possible to both (1) assess the specific merits of the batch and column experimental techniques and (2) develop an integrated research strategy for employing these techniques to quantify leaching and chemical attenuation processes under conditions relevant to the field. This review led to the conclusion that batch systems are best suited to systematically establishing the specific geochemical reactions involved in leaching and attenuation, obtaining thermodynamic and kinetic constants, and identifying the manifestation of these reactions in wastes or natural subsurface materials. 184 refs., 5 figs., 4 tabs

  15. Experimental characterization of micromilled surfaces by large range AFM

    DEFF Research Database (Denmark)

    Bariani, Paolo; Bissacco, Giuliano; Hansen, Hans Nørgaard

    2004-01-01

    of workpiece material, particularly when sub-micrometer chip thicknesses are considered and when machining hard materials. Quantification of surface topography is of fundamental importance for the evaluation of the generated surface; high resolution and wide measuring range being highly desirable...... for the evaluation of the distinctive behaviour of the ball end mill. The combination of the two demands is to date not matched by any measuring instrument. The paper describes an experimental investigation of surface topography of such micromachined surfaces. Accurate characterization of fine surface details...

  16. The Fantastic Voyage of the Trypanosome: A Protean Micromachine Perfected during 500 Million Years of Engineering

    Directory of Open Access Journals (Sweden)

    Timothy Krüger

    2018-02-01

    Full Text Available The human body is constantly attacked by pathogens. Various lines of defence have evolved, among which the immune system is principal. In contrast to most pathogens, the African trypanosomes thrive freely in the blood circulation, where they escape immune destruction by antigenic variation and incessant motility. These unicellular parasites are flagellate microswimmers that also withstand the harsh mechanical forces prevailing in the bloodstream. They undergo complex developmental cycles in the bloodstream and organs of the mammalian host, as well as the disease-transmitting tsetse fly. Each life cycle stage has been shaped by evolution for manoeuvring in distinct microenvironments. Here, we introduce trypanosomes as blueprints for nature-inspired design of trypanobots, micromachines that, in the future, could explore the human body without affecting its physiology. We review cell biological and biophysical aspects of trypanosome motion. While this could provide a basis for the engineering of microbots, their actuation and control still appear more like fiction than science. Here, we discuss potentials and challenges of trypanosome-inspired microswimmer robots.

  17. A Micromachined Pressure Sensor with Integrated Resonator Operating at Atmospheric Pressure

    Directory of Open Access Journals (Sweden)

    Sen Ren

    2013-12-01

    Full Text Available A novel resonant pressure sensor with an improved micromechanical double-ended tuning fork resonator packaged in dry air at atmospheric pressure is presented. The resonator is electrostatically driven and capacitively detected, and the sensor is designed to realize a low cost resonant pressure sensor with medium accuracy. Various damping mechanisms in a resonator that is vibrating at atmospheric pressure are analyzed in detail, and a formula is developed to predict the overall quality factor. A trade-off has been reached between the quality factor, stress sensitivity and drive capability of the resonator. Furthermore, differential sense elements and the method of electromechanical amplitude modulation are used for capacitive detection to obtain a large signal-to-noise ratio. The prototype sensor chip is successfully fabricated using a micromachining process based on a commercially available silicon-on-insulator wafer and is hermetically encapsulated in a custom 16-pin Kovar package. Preliminary measurements show that the fundamental frequency of the resonant pressure sensor is approximately 34.55 kHz with a pressure sensitivity of 20.77 Hz/kPa. Over the full scale pressure range of 100–400 kPa and the whole temperature range of −20–60 °C, high quality factors from 1,146 to 1,772 are obtained. The characterization of the prototype sensor reveals the feasibility of a resonant pressure sensor packaged at atmospheric pressure.

  18. Sapphire capillaries for laser-driven wakefield acceleration in plasma. Fs-laser micromachining and characterization

    Energy Technology Data Exchange (ETDEWEB)

    Schwinkendorf, Jan-Patrick

    2012-08-15

    Plasma wakefields are a promising approach for the acceleration of electrons with ultrahigh (10 to 100 GV/m) electric fields. Nowadays, high-intensity laser pulses are routinely utilized to excite these large-amplitude plasma waves. However, several detrimental effects such as laser diffraction, electron-wake dephasing and laser depletion may terminate the acceleration process. Two of these phenomena can be mitigated or avoided by the application of capillary waveguides, e.g. fabricated out of sapphire for longevity. Capillaries may compensate for laser diffraction like a fiber and allow for the creation of tapered gas-density profiles working against the dephasing between the accelerating wave and the particles. Additionally, they offer the possibility of controlled particle injection. This thesis is reporting on the set up of a laser for fs-micromachining of capillaries of almost arbitrary shapes and a test stand for density-profile characterization. These devices will permit the creation of tailored gas-density profiles for controlled electron injection and acceleration inside plasma.

  19. Reverberation Reduction in Capacitive Micromachined Ultrasonic Transducers (CMUTs) by Front-face Reflectivity Minimization

    Science.gov (United States)

    Savoia, Alessandro Stuart; La Mura, Monica; Mauti, Barbara; Lamberti, Nicola; Caliano, Giosuè

    Front-face acoustic reflectivity of ultrasonic imaging transducers, due to acoustic impedance mismatch with the propagation medium, may cause reverberation phenomena during wideband pulse-echo operation. Front-face reflectivity may be reduced by promoting the transmission of the echoes, received from the medium, to the transducer backing, and by maximizing the mechanical-to-electrical energy conversion and dissipation by tuning the electrical load impedance connected to the transducer. In Capacitive Micromachined Ultrasonic Transducers (CMUTs), the energy transfer from the medium to the backing is very low due to the large impedance mismatch between the medium and the transducer substrate, typically made of silicon. Reverse Fabrication Process (RFP) makes it possible providing CMUTs with custom substrate materials, thus eliminating the original silicon microfabrication support. In this paper, we propose two methods for the front-face reflectivity reduction in RFP-CMUTs: the first one is based on the use of low-impedance, highly attenuating backing materials, and the second one is based on the maximization of the mechanoelectrical energy conversion and dissipation. We analyze the methods by finite element simulations and experimentally validate the obtained results by fabricating and characterizing single-element RFP-CMUTs provided with different backing materials and electrical loads.

  20. Capacitive micromachined ultrasonic transducers based on annular cell geometry for air-coupled applications.

    Science.gov (United States)

    Na, Shuai; Chen, Albert I H; Wong, Lawrence L P; Li, Zhenhao; Macecek, Mirek; Yeow, John T W

    2016-09-01

    A novel design of an air-coupled capacitive micromachined ultrasonic transducer (CMUT) with annular cell geometry (annular CMUT) is proposed. Finite element analysis shows that an annular cell has a ratio of average-to-maximum displacement (RAMD) of 0.52-0.58 which is 58-76% higher than that of a conventional circular cell. The increased RAMD leads to a larger volume displacement which results in a 48.4% improved transmit sensitivity and 127.3% improved power intensity. Single-cell annular CMUTs were fabricated with 20-μm silicon plates on 13.7-μm deep and 1.35-mm wide annular cavities using the wafer bonding technique. The measured RAMD of the fabricated CMUTs is 0.54. The resonance frequency was measured to be 94.5kHz at 170-V DC bias. The transmit sensitivity was measured to be 33.83Pa/V and 25.85Pa/V when the CMUT was excited by a continuous wave and a 20-cycle burst, respectively. The receive sensitivity at 170-V DC bias was measured to be 7.7mV/Pa for a 20-cycle burst, and 15.0mV/Pa for a continuous incident wave. The proposed annular CMUT design demonstrates a significant improvement in transmit efficiency, which is an important parameter for air-coupled ultrasonic transducers. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. Development of capacitive Micromachined Ultrasonic Transducer (II) - Analysis of Microfabrication Process

    International Nuclear Information System (INIS)

    Kim, Ki Bok; Ahn, Bong Young; Park, Hae Won; Kim, Young Joo; Kim, Kuk Jin; Lee, Seung Seok

    2004-01-01

    The main goal of this study was to develop a micro-fabrication process for the capacitive micromachined ultrasonic transducer (cMUT). In order to achieve this goal, the former research results of the micro-electro-mechanical system (MEMS) process for the cMUT were analyzed. The membrane deposition, sacrificial layer deposition and etching were found to be a main process of fabricating the cMUT. The optimal conditions for those microfabrication were determined by the experiment. The thickness, uniformity, and residual stress of the Si 3 N 3 deposition which forms the membrane of the cMUT were characterized after growing the Si 3 N 3 on Si-wafer under various process conditions. As a sacrificial layer, the growth rate of the SiO 2 deposition was analyzed under several process conditions. The optimal etching conditions of the sacrificial layer were analyzed. The microfabrication process developed in this study will be used to fabricate the cMUT

  2. Capacitive micromachined ultrasonic transducer for ultra-low pressure measurement: Theoretical study

    Science.gov (United States)

    Li, Zhikang; Zhao, Libo; Jiang, Zhuangde; Akhbari, Sina; Ding, Jianjun; Zhao, Yihe; Zhao, Yulong; Lin, Liwei

    2015-12-01

    Ultra-low pressure measurement is necessary in many areas, such as high-vacuum environment monitoring, process control and biomedical applications. This paper presents a novel approach for ultra-low pressure measurement where capacitive micromachined ultrasonic transducers (CMUTs) are used as the sensing elements. The working principle is based on the resonant frequency shift of the membrane under the applied pressure. The membranes of the biased CMUTs can produce a larger resonant frequency shift than the diaphragms with no DC bias in the state-of-the-art resonant pressure sensors, which contributes to pressure sensitivity improvement. The theoretical analysis and finite element method (FEM) simulation were employed to study the relationship between the resonant frequency and the pressure. The results demonstrated excellent capability of the CMUTs for ultra-low pressure measurement. It is shown that the resonant frequency of the CMUT varies linearly with the applied pressure. A sensitivity of more than 6.33 ppm/Pa (68 kHz/kPa) was obtained within a pressure range of 0 to 100 Pa when the CMUTs were biased at a DC voltage of 90% of the collapse voltage. It was also demonstrated that the pressure sensitivity can be adjusted by the DC bias voltage. In addition, the effects of air damping and ambient temperature on the resonant frequency were also studied. The effect of air damping is negligible for the pressures below 1000 Pa. To eliminate the temperature effect on the resonant frequency, a temperature compensating method was proposed.

  3. Development of capacitive Micromachined Ultrasonic Transducer (II) - Analysis of Microfabrication Process

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ki Bok; Ahn, Bong Young; Park, Hae Won; Kim, Young Joo; Kim, Kuk Jin; Lee, Seung Seok [Korea Research Institute of Standards and Science, Daejeon (Korea, Republic of)

    2004-12-15

    The main goal of this study was to develop a micro-fabrication process for the capacitive micromachined ultrasonic transducer (cMUT). In order to achieve this goal, the former research results of the micro-electro-mechanical system (MEMS) process for the cMUT were analyzed. The membrane deposition, sacrificial layer deposition and etching were found to be a main process of fabricating the cMUT. The optimal conditions for those microfabrication were determined by the experiment. The thickness, uniformity, and residual stress of the Si{sub 3}N{sub 3} deposition which forms the membrane of the cMUT were characterized after growing the Si{sub 3}N{sub 3} on Si-wafer under various process conditions. As a sacrificial layer, the growth rate of the SiO{sub 2} deposition was analyzed under several process conditions. The optimal etching conditions of the sacrificial layer were analyzed. The microfabrication process developed in this study will be used to fabricate the cMUT

  4. Anodic bonding using SOI wafer for fabrication of capacitive micromachined ultrasonic transducers

    International Nuclear Information System (INIS)

    Bellaredj, M; Bourbon, G; Walter, V; Moal, P Le; Berthillier, M

    2014-01-01

    In medical ultrasound imaging, mostly piezoelectric crystals are used as ultrasonic transducers. Capacitive micromachined ultrasonic transducers (CMUTs) introduced around 1994 have been shown to be a good alternative to conventional piezoelectric transducers in various aspects, such as sensitivity, transduction efficiency or bandwidth. This paper focuses on a fabrication process for CMUTs using anodic bonding of a silicon on insulator wafer on a glass wafer. The processing steps are described leading to a good control of the mechanical response of the membrane. This technology makes possible the fabrication of large membranes and can extend the frequency range of CMUTs to lower frequencies of operation. Silicon membranes having radii of 50, 70, 100 and 150 µm and a 1.5 µm thickness are fabricated and electromechanically characterized using an auto-balanced bridge impedance analyzer. Resonant frequencies from 0.6 to 2.3 MHz and an electromechanical coupling coefficient around 55% are reported. The effects of residual stress in the membranes and uncontrolled clamping conditions are clearly responsible for the discrepancies between experimental and theoretical values of the first resonance frequency. The residual stress in the membranes is determined to be between 90 and 110 MPa. The actual boundary conditions are between the clamped condition and the simply supported condition and can be modeled with a torsional stiffness of 2.10 −7  Nm rad –1  in the numerical model. (paper)

  5. Optoacoustic characterization of broadband directivity patterns of capacitive micromachined ultrasonic transducers

    Science.gov (United States)

    Rebling, Johannes; Warshavski, Omri; Meynier, Cyril; Razansky, Daniel

    2017-04-01

    Frequency characteristics of ultrasound detectors used in optoacoustic tomography have a major impact on imaging performance. It is common practice to select transducers based on their sensitivity at the central frequency and under normal incidence. However, the bandwidth and angular sensitivity play an equally important role in establishing the quality and accuracy of the reconstructed images. Here, we developed a calibrated optoacoustic characterization method specifically tailored for broadband measurements of the angular transducer sensitivity (directivity). Ultrawideband omnidirectional optoacoustic responses were generated by uniformly illuminating thin absorbing sutures with nanosecond laser pulses and characterized with a needle hydrophone. This calibrated optoacoustic source was used to characterize the frequency dependence of the angular response by a conventional piezoelectric transducer (PZT) and a capacitive micromachined ultrasonic transducer (cMUT) with similar size and central frequency. Furthermore, both transducers had no preamplification electronics directly attached to the detection elements. While the PZT presented a 7.8 dB sensitivity advantage at normal incidence, it was able to provide detectable signal-to-noise levels only at incidence angles of up to 20 deg whereas the cMUT maintained reasonable sensitivity levels and broadband response at incidence angles of 40 deg and beyond. We further experimentally showcase a reduction in the limited-view image artifacts resulting from the broader acceptance angle of the cMUT.

  6. Two Capacitive Micro-Machined Ultrasonic Transducers for Wind Speed Measurement.

    Science.gov (United States)

    Bui, Gia Thinh; Jiang, Yu-Tsung; Pang, Da-Chen

    2016-06-02

    This paper presents a new wind speed measurement method using a single capacitive micro-machined ultrasonic transducer (CMUT). The CMUT was arranged perpendicular to the direction of the wind flow, and a reflector was set up a short distance away, facing the CMUT. To reduce the size, weight, cost, and power consumption of conventional ultrasonic anemometers this study proposes two CMUT designs for the measurement of wind speed using either the amplitude of the signal or the time of flight (TOF). Each CMUT with a double array element design can transmit and receive signals in five different operation modes. Experiments showed that the two CMUT designs utilizing the TOF were better than those utilizing the amplitude of the signal for wind speed measurements ranging from 1 m/s to 10 m/s, providing a measurement error of less than 0.2 m/s. These results indicate that the sensitivity of the TOF is independent of the five operation modes.

  7. Two Capacitive Micro-Machined Ultrasonic Transducers for Wind Speed Measurement

    Directory of Open Access Journals (Sweden)

    Gia Thinh Bui

    2016-06-01

    Full Text Available This paper presents a new wind speed measurement method using a single capacitive micro-machined ultrasonic transducer (CMUT. The CMUT was arranged perpendicular to the direction of the wind flow, and a reflector was set up a short distance away, facing the CMUT. To reduce the size, weight, cost, and power consumption of conventional ultrasonic anemometers this study proposes two CMUT designs for the measurement of wind speed using either the amplitude of the signal or the time of flight (TOF. Each CMUT with a double array element design can transmit and receive signals in five different operation modes. Experiments showed that the two CMUT designs utilizing the TOF were better than those utilizing the amplitude of the signal for wind speed measurements ranging from 1 m/s to 10 m/s, providing a measurement error of less than 0.2 m/s. These results indicate that the sensitivity of the TOF is independent of the five operation modes.

  8. Short-pulse-width micromachining of hard materials using DPSS Nd:YAG lasers

    Science.gov (United States)

    Heglin, Michael; Govorkov, Sergei V.; Scaggs, Michael J.; Theoharidis, Haris; Schoelzel, T.

    2002-06-01

    The material processing of an industrial, short-pulse duration DPPS YAG laser producing peak powers greater than 0.2MW is discussed in this paper. This peak power provides sufficient materials processing capability to meet the micro machining needs in the automotive, semiconductor, micro- electronic, medical and telecommunication industries. All hard and soft materials including: plastics, metals, ceramics, diamond and other crystalline materials are suitable candidates for the processing capability of this laser. Micro level features can be machined in these materials to a depth in excess of 1mm with high quality results. In most applications feature sizes can be achieved that are not possible or economical with existing technologies. The optical beam delivery system requirements, and overall micro-machining set-up are also described. The drilling and cutting versatility down to feature sizes of less than 7 micrometers , as well as, complex shapes are shown. The wavelength, pulse length, and peakpower are described and relate to their effect on recast, micro-cracking and material removal rates. Material removal effects related to progressive penetration into the material will be reviewed. The requirements of this DPSS laser technology to meet the operational requirements for high duty cycle operation in industrial environments is covered along with processing flexibility and lower operating cost.

  9. Micromachining and dicing of sapphire, gallium nitride and micro LED devices with UV copper vapour laser

    International Nuclear Information System (INIS)

    Gu, E.; Jeon, C.W.; Choi, H.W.; Rice, G.; Dawson, M.D.; Illy, E.K.; Knowles, M.R.H.

    2004-01-01

    Gallium nitride (GaN) and sapphire are important materials for fabricating photonic devices such as high brightness light emitting diodes (LEDs). These materials are strongly resistant to wet chemical etching and also, low etch rates restrict the use of dry etching. Thus, to develop alternative high resolution processing and machining techniques for these materials is important in fabricating novel photonic devices. In this work, a repetitively pulsed UV copper vapour laser (255 nm) has been used to machine and dice sapphire, GaN and micro LED devices. Machining parameters were optimised so as to achieve controllable machining and high resolution. For sapphire, well-defined grooves 30 μm wide and 430 μm deep were machined. For GaN, precision features such as holes on a tens of micron length scale have been fabricated. By using this technique, compact micro LED chips with a die spacing 100 and a 430 μm thick sapphire substrate have been successfully diced. Measurements show that the performances of LED devices are not influenced by the UV laser machining. Our results demonstrate that the pulsed UV copper vapour laser is a powerful tool for micromachining and dicing of photonic materials and devices

  10. A novel deflection shape function for rectangular capacitive micromachined ultrasonic transducer diaphragms

    Directory of Open Access Journals (Sweden)

    Zhou Zheng

    2015-09-01

    Full Text Available A highly accurate analytical deflection shape function that describes the deflection profiles of capacitive micromachined ultrasonic transducers (CMUTs with rectangular membranes under electrostatic pressure has been formulated. The rectangular diaphragms have a thickness range of 0.6–1.5 μm and a side length range of 100–1000 μm. The new deflection shape function generates deflection profiles that are in excellent agreement with finite element analysis (FEA results for a wide range of geometry dimensions and loading conditions. The deflection shape function is used to analyze membrane deformations and to calculate the capacitances between the deformed membranes and the fixed back plates. In 50 groups of random tests, compared with FEA results, the calculated capacitance values have a maximum deviation of 1.486% for rectangular membranes. The new analytical deflection function can provide designers with a simple way of gaining insight into the effects of designed parameters for CMUTs and other MEMS-based capacitive type sensors.

  11. Experimental Study of the Ultrasonic Vibration-Assisted Abrasive Waterjet Micromachining the Quartz Glass

    Directory of Open Access Journals (Sweden)

    Rongguo Hou

    2018-01-01

    Full Text Available The ultrasonic vibration is used to enhance the capability of the abrasive water micromachining glass. And, the ultrasonic vibration is activated on the abrasive waterjet nozzle. The quality of the flow is improved, and the velocity of the abrasive is increased because of the addition of the ultrasonic energy. The relevant experimental results indicate that the erosion depth and the material volume removal of the glass are obviously increased when ultrasonic vibration is working. As for the influence of process parameters on the material removal of the glass such as vibration amplitude, system pressure, distance of the standoff, and abrasive size, the experimental results indicate that the system pressure and vibration contribute greatly to the glass material removal. Also, the erosion depth and the volume of material removal are increased with the increase in the vibration amplitude and system pressure. There are some uplifts found at the edge of erosion pit. Then, it can be inferred that the plastic method is an important material removal method during the machining process of ultrasonic vibration-assisted abrasive waterjet.

  12. Two Novel Measurements for the Drive-Mode Resonant Frequency of a Micromachined Vibratory Gyroscope

    Directory of Open Access Journals (Sweden)

    Ancheng Wang

    2013-11-01

    Full Text Available To investigate the drive-mode resonance frequency of a micromachined vibratory gyroscope (MVG, one needs to measure it accurately and efficiently. The conventional approach to measure the resonant frequency is by performing a sweep frequency test and spectrum analysis. The method is time-consuming and inconvenient because of the requirements of many test points, a lot of data storage and off-line analyses. In this paper, we propose two novel measurement methods, the search method and track method, respectively. The former is based on the magnitude-frequency characteristics of the drive mode, utilizing a one-dimensional search technique. The latter is based on the phase-frequency characteristics, applying a feedback control loop. Their performances in precision, noise resistivity and efficiency are analyzed through detailed simulations. A test system is implemented based on a field programmable gate array (FPGA and experiments are carried out. By comparing with the common approach, feasibility and superiorities of the proposed methods are validated. In particular, significant efficiency improvements are achieved whereby the conventional frequency method consumes nearly 5,000 s to finish a measurement, while only 5 s is needed for the track method and 1 s for the search method.

  13. Modeling the Microstructure Curvature of Boron-Doped Silicon in Bulk Micromachined Accelerometer

    Directory of Open Access Journals (Sweden)

    Xiaoping He

    2013-01-01

    Full Text Available Microstructure curvature, or buckling, is observed in the micromachining of silicon sensors because of the doping of impurities for realizing certain electrical and mechanical processes. This behavior can be a key source of error in inertial sensors. Therefore, identifying the factors that influence the buckling value is important in designing MEMS devices. In this study, the curvature in the proof mass of an accelerometer is modeled as a multilayered solid model. Modeling is performed according to the characteristics of the solid diffusion mechanism in the bulk-dissolved wafer process (BDWP based on the self-stopped etch technique. Moreover, the proposed multilayered solid model is established as an equivalent composite structure formed by a group of thin layers that are glued together. Each layer has a different Young’s modulus value and each undergoes different volume shrinkage strain owing to boron doping in silicon. Observations of five groups of proof mass blocks of accelerometers suggest that the theoretical model is effective in determining the buckling value of a fabricated structure.

  14. On-chip micromachined dipole antenna with parasitic radiator for mm-wave wireless systems

    KAUST Repository

    Sallam, Mai O.

    2016-12-19

    In this paper, we present a micromachined dipole antenna with parasitic radiator. The antenna is designed for operation at 60 GHz. It consists of two Ig/2 dipole radiators fed by coplanar strips waveguide. Two slightly shorter dipoles are placed in proximity to the main radiators. They act as parasitic dipole arms which increase the bandwidth of the antenna. Two versions of the same antenna topology are presented in this paper in which one uses a high resistivity silicon substrate while the other uses a low resistivity one. The proposed antenna was optimized using HFSS and the final design was simulated using both HFSS and CST for verifying the obtained results. Both simulators are in good agreement. They show that the antenna has very good radiation characteristics where its directivity is around 7.5 dBi. The addition of the parasitic arms increased the bandwidth of the antenna from 1.3 GHz (3.62 GHz) to 4.3 GHz (7.44 GHz) when designed on high (low) resistivity silicon substrate.

  15. A Z-Axis Quartz Cross-Fork Micromachined Gyroscope Based on Shear Stress Detection

    Science.gov (United States)

    Xie, Liqiang; Wu, Xuezhong; Li, Shengyi; Wang, Haoxu; Su, Jianbin; Dong, Peitao

    2010-01-01

    Here we propose a novel quartz micromachined gyroscope. The sensor has a simple cross-fork structure in the x-y plane of quartz crystal. Shear stress rather than normal stress is utilized to sense Coriolis’ force generated by the input angular rate signal. Compared to traditional quartz gyroscopes, which have two separate sense electrodes on each sidewall, there is only one electrode on each sidewall of the sense beam. As a result, the fabrication of the electrodes is simplified and the structure can be easily miniaturized. In order to increase sensitivity, a pair of proof masses is attached to the ends of the drive beam, and the sense beam has a tapered design. The structure is etched from a z-cut quartz wafer and the electrodes are realized by direct evaporation using the aperture mask method. The drive mode frequency of the prototype is 13.38 kHz, and the quality factor is approximately 1,000 in air. Therefore, the gyroscope can work properly without a vacuum package. The measurement ability of the shear stress detection design scheme is validated by the Coriolis’ force test. The performance of the sensor is characterized on a precision rate table using a specially designed readout circuit. The experimentally obtained scale factor is 1.45 mV/°/s and the nonlinearity is 3.6% in range of ±200 °/s. PMID:22294887

  16. Sapphire capillaries for laser-driven wakefield acceleration in plasma. Fs-laser micromachining and characterization

    International Nuclear Information System (INIS)

    Schwinkendorf, Jan-Patrick

    2012-05-01

    Plasma wakefields are a promising approach for the acceleration of electrons with ultrahigh (10 to 100 GV/m) electric fields. Nowadays, high-intensity laser pulses are routinely utilized to excite these large-amplitude plasma waves. However, several detrimental effects such as laser diffraction, electron-wake dephasing and laser depletion may terminate the acceleration process. Two of these phenomena can be mitigated or avoided by the application of capillary waveguides, e.g. fabricated out of sapphire for longevity. Capillaries may compensate for laser diffraction like a fiber and allow for the creation of tapered gas-density profiles working against the dephasing between the accelerating wave and the particles. Additionally, they offer the possibility of controlled particle injection. This thesis is reporting on the set up of a laser for fs-micromachining of capillaries of almost arbitrary shapes and a test stand for density-profile characterization. These devices will permit the creation of tailored gas-density profiles for controlled electron injection and acceleration inside plasma.

  17. 31-mode piezoelectric micromachined ultrasonic transducer with PZT thick film by granule spraying in vacuum process

    Science.gov (United States)

    Jung, Joontaek; Annapureddy, Venkateswarlu; Hwang, Geon-Tae; Song, Youngsup; Lee, Wonjun; Kang, Woojin; Ryu, Jungho; Choi, Hongsoo

    2017-05-01

    A piezoelectric micromachined ultrasonic transducer (pMUT) is an ideal device for portable medical diagnosis systems, intravascular ultrasound systems, and ultrasonic cameras because of its favorable characteristics including small size, acoustic impedance matching with the body, low power consumption, and simple integration with the systems. Despite these advantages, practical applications are limited because of insufficient acoustic pressure of the pMUT caused by the thin active piezoelectric layer. Here, we report the fabrication of a thick piezoelectric Pb(Zr,Ti)O3 (PZT) film-based pMUT device having high deflection at low driving voltage using the granule spraying in vacuum (GSV) process. Pre-patterned high-density thick (exceeding 8 μm) PZT films were grown on 6-inch-diameter Si/SiO2/Ti/Pt silicon-on-insulator wafers at room temperature at a high deposition rate of ˜5 μm min-1. The fabrication process using the proposed GSV process was simple and fast, and the deflection of the pMUT exhibited a high value of 0.8 μm.

  18. Improving groundwater storage and soil moisture estimates by assimilating GRACE, SMOS, and SMAP data into CABLE using ensemble Kalman batch smoother and particle batch smoother frameworks

    Science.gov (United States)

    Han, S. C.; Tangdamrongsub, N.; Yeo, I. Y.; Dong, J.

    2017-12-01

    Soil moisture and groundwater storage are important information for comprehensive understanding of the climate system and accurate assessment of the regional/global water resources. It is possible to derive the water storage from land surface models but the outputs are commonly biased by inaccurate forcing data, inefficacious model physics, and improper model parameter calibration. To mitigate the model uncertainty, the observation (e.g., from remote sensing as well as ground in-situ data) are often integrated into the models via data assimilation (DA). This study aims to improve the estimation of soil moisture and groundwater storage by simultaneously assimilating satellite observations from the Gravity Recovery And Climate Experiment (GRACE), the Soil Moisture Ocean Salinity (SMOS), and the Soil Moisture Active Passive (SMAP) into the Community Atmosphere Biosphere Land Exchange (CABLE) land surface model using the ensemble Kalman batch smoother (EnBS) and particle batch smoother (PBS) frameworks. The uncertainty of GRACE observation is obtained rigorously from the full error variance-covariance matrix of the GRACE data product. This method demonstrates the use of a realistic representative of GRACE uncertainty, which is spatially correlated in nature, leads to a higher accuracy of water storage computation. Additionally, the comparison between EnBS and PBS results is discussed to understand the filter's performance, limitation, and suitability. The joint DA is demonstrated in the Goulburn catchment, South-East Australia, where diverse ground observations (surface soil moisture, root-zone soil moisture, and groundwater level) are available for evaluation of our DA results. Preliminary results show that both smoothers provide significant improvement of surface soil moisture and groundwater storage estimates. Importantly, our developed DA scheme disaggregates the catchment-scale GRACE information into finer vertical and spatial scales ( 25 km). We present an

  19. 40 CFR 63.1326 - Batch process vents-recordkeeping provisions.

    Science.gov (United States)

    2010-07-01

    ... operator of a batch process vent that has chosen to use a control device to comply with § 63.1322(a) shall... 40 Protection of Environment 11 2010-07-01 2010-07-01 true Batch process vents-recordkeeping... Batch process vents—recordkeeping provisions. (a) Group determination records for batch process vents...

  20. 40 CFR 63.487 - Batch front-end process vents-reference control technology.

    Science.gov (United States)

    2010-07-01

    ... § 63.487 Batch front-end process vents—reference control technology. (a) Batch front-end process vents... process vent, reduce organic HAP emissions for the batch cycle by 90 weight percent using a control device... 40 Protection of Environment 9 2010-07-01 2010-07-01 false Batch front-end process vents-reference...

  1. 40 CFR 63.491 - Batch front-end process vents-recordkeeping requirements.

    Science.gov (United States)

    2010-07-01

    ... combustion device to control halogenated batch front-end process vents or halogenated aggregate batch vent... periods of process or control device operation when monitors are not operating. (f) Aggregate batch vent... 40 Protection of Environment 9 2010-07-01 2010-07-01 false Batch front-end process vents...

  2. 40 CFR 63.489 - Batch front-end process vents-monitoring equipment.

    Science.gov (United States)

    2010-07-01

    ... operator of a batch front-end process vent or aggregate batch vent stream that uses a control device to... meets the conditions of § 63.490(b)(3). (i) For batch front-end process vents using a control device to... 40 Protection of Environment 9 2010-07-01 2010-07-01 false Batch front-end process vents...

  3. 40 CFR 63.492 - Batch front-end process vents-reporting requirements.

    Science.gov (United States)

    2010-07-01

    ... recorded under § 63.491(e)(3) when the batch front-end process vent is diverted away from the control... 40 Protection of Environment 9 2010-07-01 2010-07-01 false Batch front-end process vents-reporting... Batch front-end process vents—reporting requirements. (a) The owner or operator of a batch front-end...

  4. Towards Batched Linear Solvers on Accelerated Hardware Platforms

    Energy Technology Data Exchange (ETDEWEB)

    Haidar, Azzam [University of Tennessee (UT); Dong, Tingzing Tim [University of Tennessee (UT); Tomov, Stanimire [University of Tennessee (UT); Dongarra, Jack J [ORNL

    2015-01-01

    As hardware evolves, an increasingly effective approach to develop energy efficient, high-performance solvers, is to design them to work on many small and independent problems. Indeed, many applications already need this functionality, especially for GPUs, which are known to be currently about four to five times more energy efficient than multicore CPUs for every floating-point operation. In this paper, we describe the development of the main one-sided factorizations: LU, QR, and Cholesky; that are needed for a set of small dense matrices to work in parallel. We refer to such algorithms as batched factorizations. Our approach is based on representing the algorithms as a sequence of batched BLAS routines for GPU-contained execution. Note that this is similar in functionality to the LAPACK and the hybrid MAGMA algorithms for large-matrix factorizations. But it is different from a straightforward approach, whereby each of GPU's symmetric multiprocessors factorizes a single problem at a time. We illustrate how our performance analysis together with the profiling and tracing tools guided the development of batched factorizations to achieve up to 2-fold speedup and 3-fold better energy efficiency compared to our highly optimized batched CPU implementations based on the MKL library on a two-sockets, Intel Sandy Bridge server. Compared to a batched LU factorization featured in the NVIDIA's CUBLAS library for GPUs, we achieves up to 2.5-fold speedup on the K40 GPU.

  5. From Fed-batch to Continuous Enzymatic Biodiesel Production

    DEFF Research Database (Denmark)

    Price, Jason Anthony; Nordblad, Mathias; Woodley, John M.

    2015-01-01

    In this this paper, we use mechanistic modelling to guide the development of acontinuous enzymatic process that is performed as a fed-batch operation. In this workwe use the enzymatic biodiesel process as a case study. A mechanistic model developedin our previous work was used to determine...... measured components (triglycerides, diglycerides, monoglycerides, free fatty acid and fatty acid methyl esters(biodiesel)) much better than using fed-batch data alone given the smaller residuals. We also observe a reduction in the correlation between the parameters.The model was then used to predict that 5...... reactors are required (with a combined residence time of 30 hours) to reach a final biodiesel concentration within 2 % of the95.6 mass % achieved in a fed-batch operation, for 24 hours....

  6. Batch variation between branchial cell cultures: An analysis of variance

    DEFF Research Database (Denmark)

    Hansen, Heinz Johs. Max; Grosell, M.; Kristensen, L.

    2003-01-01

    We present in detail how a statistical analysis of variance (ANOVA) is used to sort out the effect of an unexpected batch-to-batch variation between cell cultures. Two separate cultures of rainbow trout branchial cells were grown on permeable filtersupports ("inserts"). They were supposed...... to be simple duplicates for testing the effect of two induced factors-apical or basolateral addition of radioactive precursors and different apical media-on the incorporation of 14C-acetate and 32Pphosphate intotissue lipids. Unfortunately, they did not altogether give the same result. By accepting this fact...... and introducing the observed difference between batches as one of the factors in an expanded three-dimensional ANOVA, we were able to overcome an otherwisecrucial lack of sufficiently reproducible duplicate values. We could thereby show that the effect of changing the apical medium was much more marked when...

  7. A High-Fidelity Batch Simulation Environment for Integrated Batch and Piloted Air Combat Simulation Analysis

    Science.gov (United States)

    Goodrich, Kenneth H.; McManus, John W.; Chappell, Alan R.

    1992-01-01

    A batch air combat simulation environment known as the Tactical Maneuvering Simulator (TMS) is presented. The TMS serves as a tool for developing and evaluating tactical maneuvering logics. The environment can also be used to evaluate the tactical implications of perturbations to aircraft performance or supporting systems. The TMS is capable of simulating air combat between any number of engagement participants, with practical limits imposed by computer memory and processing power. Aircraft are modeled using equations of motion, control laws, aerodynamics and propulsive characteristics equivalent to those used in high-fidelity piloted simulation. Databases representative of a modern high-performance aircraft with and without thrust-vectoring capability are included. To simplify the task of developing and implementing maneuvering logics in the TMS, an outer-loop control system known as the Tactical Autopilot (TA) is implemented in the aircraft simulation model. The TA converts guidance commands issued by computerized maneuvering logics in the form of desired angle-of-attack and wind axis-bank angle into inputs to the inner-loop control augmentation system of the aircraft. This report describes the capabilities and operation of the TMS.

  8. Continuous flow technology vs. the batch-by-batch approach to produce pharmaceutical compounds.

    Science.gov (United States)

    Cole, Kevin P; Johnson, Martin D

    2018-01-01

    For the manufacture of small molecule drugs, many pharmaceutical innovator companies have recently invested in continuous processing, which can offer significant technical and economic advantages over traditional batch methodology. This Expert Review will describe the reasons for this interest as well as many considerations and challenges that exist today concerning continuous manufacturing. Areas covered: Continuous processing is defined and many reasons for its adoption are described. The current state of continuous drug substance manufacturing within the pharmaceutical industry is summarized. Current key challenges to implementation of continuous manufacturing are highlighted, and an outlook provided regarding the prospects for continuous within the industry. Expert commentary: Continuous processing at Lilly has been a journey that started with the need for increased safety and capability. Over twelve years the original small, dedicated group has grown to more than 100 Lilly employees in discovery, development, quality, manufacturing, and regulatory designing in continuous drug substance processing. Recently we have focused on linked continuous unit operations for the purpose of all-at-once pharmaceutical manufacturing, but the technical and business drivers that existed in the very beginning for stand-alone continuous unit operations in hybrid processes have persisted, which merits investment in both approaches.

  9. Stochastic growth logistic model with aftereffect for batch fermentation process

    International Nuclear Information System (INIS)

    Rosli, Norhayati; Ayoubi, Tawfiqullah; Bahar, Arifah; Rahman, Haliza Abdul; Salleh, Madihah Md

    2014-01-01

    In this paper, the stochastic growth logistic model with aftereffect for the cell growth of C. acetobutylicum P262 and Luedeking-Piret equations for solvent production in batch fermentation system is introduced. The parameters values of the mathematical models are estimated via Levenberg-Marquardt optimization method of non-linear least squares. We apply Milstein scheme for solving the stochastic models numerically. The effciency of mathematical models is measured by comparing the simulated result and the experimental data of the microbial growth and solvent production in batch system. Low values of Root Mean-Square Error (RMSE) of stochastic models with aftereffect indicate good fits

  10. Stochastic growth logistic model with aftereffect for batch fermentation process

    Energy Technology Data Exchange (ETDEWEB)

    Rosli, Norhayati; Ayoubi, Tawfiqullah [Faculty of Industrial Sciences and Technology, Universiti Malaysia Pahang, Lebuhraya Tun Razak, 26300 Gambang, Pahang (Malaysia); Bahar, Arifah; Rahman, Haliza Abdul [Department of Mathematical Sciences, Faculty of Science, Universiti Teknologi Malaysia, 81310 Johor Bahru, Johor (Malaysia); Salleh, Madihah Md [Department of Biotechnology Industry, Faculty of Biosciences and Bioengineering, Universiti Teknologi Malaysia, 81310 Johor Bahru, Johor (Malaysia)

    2014-06-19

    In this paper, the stochastic growth logistic model with aftereffect for the cell growth of C. acetobutylicum P262 and Luedeking-Piret equations for solvent production in batch fermentation system is introduced. The parameters values of the mathematical models are estimated via Levenberg-Marquardt optimization method of non-linear least squares. We apply Milstein scheme for solving the stochastic models numerically. The effciency of mathematical models is measured by comparing the simulated result and the experimental data of the microbial growth and solvent production in batch system. Low values of Root Mean-Square Error (RMSE) of stochastic models with aftereffect indicate good fits.

  11. Analysis and modelling of the energy requirements of batch processes; Analyse und Modellierung des Energiebedarfes in Batch-Prozessen

    Energy Technology Data Exchange (ETDEWEB)

    Bieler, P.S.

    2002-07-01

    This intermediate report for the Swiss Federal Office of Energy (SFOE) presents the results of a project aiming to model the energy consumption of multi-product, multi-purpose batch production plants. The utilities investigated were electricity, brine and steam. Both top-down and bottom-up approaches are described, whereby top-down was used for the buildings where the batch process apparatus was installed. Modelling showed that for batch-plants at the building level, the product mix can be too variable and the diversity of products and processes too great for simple modelling. Further results obtained by comparing six different production plants that could be modelled are discussed. The several models developed are described and their wider applicability is discussed. Also, the results of comparisons made between modelled and actual values are presented. Recommendations for further work are made.

  12. Design of two-column batch-to-batch recirculation to enhance performance in ion-exchange chromatography.

    Science.gov (United States)

    Persson, Oliver; Andersson, Niklas; Nilsson, Bernt

    2018-01-05

    Preparative liquid chromatography is a separation technique widely used in the manufacturing of fine chemicals and pharmaceuticals. A major drawback of traditional single-column batch chromatography step is the trade-off between product purity and process performance. Recirculation of impure product can be utilized to make the trade-off more favorable. The aim of the present study was to investigate the usage of a two-column batch-to-batch recirculation process step to increase the performance compared to single-column batch chromatography at a high purity requirement. The separation of a ternary protein mixture on ion-exchange chromatography columns was used to evaluate the proposed process. The investigation used modelling and simulation of the process step, experimental validation and optimization of the simulated process. In the presented case the yield increases from 45.4% to 93.6% and the productivity increases 3.4 times compared to the performance of a batch run for a nominal case. A rapid concentration build-up product can be seen during the first cycles, before the process reaches a cyclic steady-state with reoccurring concentration profiles. The optimization of the simulation model predicts that the recirculated salt can be used as a flying start of the elution, which would enhance the process performance. The proposed process is more complex than a batch process, but may improve the separation performance, especially while operating at cyclic steady-state. The recirculation of impure fractions reduces the product losses and ensures separation of product to a high degree of purity. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. The laser micro-machining system for diamond anvil cell experiments and general precision machining applications at the High Pressure Collaborative Access Team.

    Science.gov (United States)

    Hrubiak, Rostislav; Sinogeikin, Stanislav; Rod, Eric; Shen, Guoyin

    2015-07-01

    We have designed and constructed a new system for micro-machining parts and sample assemblies used for diamond anvil cells and general user operations at the High Pressure Collaborative Access Team, sector 16 of the Advanced Photon Source. The new micro-machining system uses a pulsed laser of 400 ps pulse duration, ablating various materials without thermal melting, thus leaving a clean edge. With optics designed for a tight focus, the system can machine holes any size larger than 3 μm in diameter. Unlike a standard electrical discharge machining drill, the new laser system allows micro-machining of non-conductive materials such as: amorphous boron and silicon carbide gaskets, diamond, oxides, and other materials including organic materials such as polyimide films (i.e., Kapton). An important feature of the new system is the use of gas-tight or gas-flow environmental chambers which allow the laser micro-machining to be done in a controlled (e.g., inert gas) atmosphere to prevent oxidation and other chemical reactions in air sensitive materials. The gas-tight workpiece enclosure is also useful for machining materials with known health risks (e.g., beryllium). Specialized control software with a graphical interface enables micro-machining of custom 2D and 3D shapes. The laser-machining system was designed in a Class 1 laser enclosure, i.e., it includes laser safety interlocks and computer controls and allows for routine operation. Though initially designed mainly for machining of the diamond anvil cell gaskets, the laser-machining system has since found many other micro-machining applications, several of which are presented here.

  14. The laser micro-machining system for diamond anvil cell experiments and general precision machining applications at the High Pressure Collaborative Access Team

    Science.gov (United States)

    Hrubiak, Rostislav; Sinogeikin, Stanislav; Rod, Eric; Shen, Guoyin

    2015-07-01

    We have designed and constructed a new system for micro-machining parts and sample assemblies used for diamond anvil cells and general user operations at the High Pressure Collaborative Access Team, sector 16 of the Advanced Photon Source. The new micro-machining system uses a pulsed laser of 400 ps pulse duration, ablating various materials without thermal melting, thus leaving a clean edge. With optics designed for a tight focus, the system can machine holes any size larger than 3 μm in diameter. Unlike a standard electrical discharge machining drill, the new laser system allows micro-machining of non-conductive materials such as: amorphous boron and silicon carbide gaskets, diamond, oxides, and other materials including organic materials such as polyimide films (i.e., Kapton). An important feature of the new system is the use of gas-tight or gas-flow environmental chambers which allow the laser micro-machining to be done in a controlled (e.g., inert gas) atmosphere to prevent oxidation and other chemical reactions in air sensitive materials. The gas-tight workpiece enclosure is also useful for machining materials with known health risks (e.g., beryllium). Specialized control software with a graphical interface enables micro-machining of custom 2D and 3D shapes. The laser-machining system was designed in a Class 1 laser enclosure, i.e., it includes laser safety interlocks and computer controls and allows for routine operation. Though initially designed mainly for machining of the diamond anvil cell gaskets, the laser-machining system has since found many other micro-machining applications, several of which are presented here.

  15. The laser micro-machining system for diamond anvil cell experiments and general precision machining applications at the High Pressure Collaborative Access Team

    International Nuclear Information System (INIS)

    Hrubiak, Rostislav; Sinogeikin, Stanislav; Rod, Eric; Shen, Guoyin

    2015-01-01

    We have designed and constructed a new system for micro-machining parts and sample assemblies used for diamond anvil cells and general user operations at the High Pressure Collaborative Access Team, sector 16 of the Advanced Photon Source. The new micro-machining system uses a pulsed laser of 400 ps pulse duration, ablating various materials without thermal melting, thus leaving a clean edge. With optics designed for a tight focus, the system can machine holes any size larger than 3 μm in diameter. Unlike a standard electrical discharge machining drill, the new laser system allows micro-machining of non-conductive materials such as: amorphous boron and silicon carbide gaskets, diamond, oxides, and other materials including organic materials such as polyimide films (i.e., Kapton). An important feature of the new system is the use of gas-tight or gas-flow environmental chambers which allow the laser micro-machining to be done in a controlled (e.g., inert gas) atmosphere to prevent oxidation and other chemical reactions in air sensitive materials. The gas-tight workpiece enclosure is also useful for machining materials with known health risks (e.g., beryllium). Specialized control software with a graphical interface enables micro-machining of custom 2D and 3D shapes. The laser-machining system was designed in a Class 1 laser enclosure, i.e., it includes laser safety interlocks and computer controls and allows for routine operation. Though initially designed mainly for machining of the diamond anvil cell gaskets, the laser-machining system has since found many other micro-machining applications, several of which are presented here

  16. Si Micro-turbine by Proton BeamWriting and Porous Silicon Micromachining

    International Nuclear Information System (INIS)

    Rajta, I.; Szilasi, S.Z.; Fekete, Z.

    2008-01-01

    Complete text of publication follows. A 3D Si micro-turbine characterized by high aspect ratio vertical walls was formed by the combination of proton beam writing (PBW) and subsequent selective porous Si (PS) etching. Crystal damages generated by the implanted protons result in increased resistivity, thereby limit or even prevent the current to flow through the implanted area during electrochemical etching. Characteristic feature of the proposed process is that the shape of the micro electromechanical (MEMS) components is defined by two implantation energies. A higher energy is applied for defining the housing of the device while the lower energy is used to write the moving components. The implantation energies were selected such as to result appropriate difference between the two projected ranges, thereby providing structures with different height after development. The thickness of the walls of the moving component and the isotropic etching profile of the electrochemical PS formation was also taken into consideration. The electrochemical etching is driven until the sacrificial PS layer completely under etches the moving components, but the etch-front does not reach the bottom of the housing. Therefore, the dissolution of PS results in a ready-to-operate device with a released moving component embedded in the cavity of the housing. The operation of the encapsulated device fabricated by the two-energy implantation is successfully demonstrated (Fig. 1). Rotation speed of the device is estimated in the range of thousands rpm, however, further analysis of the novel structure optimized for performance and MEMS compatible assembly will be done and precise characteristics will be determined by adequate optical read-out method. The feasibility of Proton Beam Writing combined with Porous Si Micromachining and conventional Si processing steps was successfully demonstrated by fabricating Si microturbine chip. The aligned, two-energy proton beam implantation can provide high

  17. Lipid production in batch and fed-batch cultures of Rhodosporidium toruloides from 5 and 6 carbon carbohydrates

    Directory of Open Access Journals (Sweden)

    Wiebe Marilyn G

    2012-05-01

    Full Text Available Abstract Background Microbial lipids are a potential source of bio- or renewable diesel and the red yeast Rhodosporidium toruloides is interesting not only because it can accumulate over 50% of its dry biomass as lipid, but also because it utilises both five and six carbon carbohydrates, which are present in plant biomass hydrolysates. Methods R. toruloides was grown in batch and fed-batch cultures in 0.5 L bioreactors at pH 4 in chemically defined, nitrogen restricted (C/N 40 to 100 media containing glucose, xylose, arabinose, or all three carbohydrates as carbon source. Lipid was extracted from the biomass using chloroform-methanol, measured gravimetrically and analysed by GC. Results Lipid production was most efficient with glucose (up to 25 g lipid L−1, 48 to 75% lipid in the biomass, at up to 0.21 g lipid L−1 h−1 as the sole carbon source, but high lipid concentrations were also produced from xylose (36 to 45% lipid in biomass. Lipid production was low (15–19% lipid in biomass with arabinose as sole carbon source and was lower than expected (30% lipid in biomass when glucose, xylose and arabinose were provided simultaneously. The presence of arabinose and/or xylose in the medium increased the proportion of palmitic and linoleic acid and reduced the proportion of oleic acid in the fatty acids, compared to glucose-grown cells. High cell densities were obtained in both batch (37 g L−1, with 49% lipid in the biomass and fed-batch (35 to 47 g L−1, with 50 to 75% lipid in the biomass cultures. The highest proportion of lipid in the biomass was observed in cultures given nitrogen during the batch phase but none with the feed. However, carbohydrate consumption was incomplete when the feed did not contain nitrogen and the highest total lipid and best substrate consumption were observed in cultures which received a constant low nitrogen supply. Conclusions Lipid production in R. toruloides was lower from arabinose and mixed

  18. Lipid production in batch and fed-batch cultures of Rhodosporidium toruloides from 5 and 6 carbon carbohydrates.

    Science.gov (United States)

    Wiebe, Marilyn G; Koivuranta, Kari; Penttilä, Merja; Ruohonen, Laura

    2012-05-30

    Microbial lipids are a potential source of bio- or renewable diesel and the red yeast Rhodosporidium toruloides is interesting not only because it can accumulate over 50% of its dry biomass as lipid, but also because it utilises both five and six carbon carbohydrates, which are present in plant biomass hydrolysates. R. toruloides was grown in batch and fed-batch cultures in 0.5 L bioreactors at pH 4 in chemically defined, nitrogen restricted (C/N 40 to 100) media containing glucose, xylose, arabinose, or all three carbohydrates as carbon source. Lipid was extracted from the biomass using chloroform-methanol, measured gravimetrically and analysed by GC. Lipid production was most efficient with glucose (up to 25 g lipid L(-1), 48 to 75% lipid in the biomass, at up to 0.21 g lipid L(-1) h(-1)) as the sole carbon source, but high lipid concentrations were also produced from xylose (36 to 45% lipid in biomass). Lipid production was low (15-19% lipid in biomass) with arabinose as sole carbon source and was lower than expected (30% lipid in biomass) when glucose, xylose and arabinose were provided simultaneously. The presence of arabinose and/or xylose in the medium increased the proportion of palmitic and linoleic acid and reduced the proportion of oleic acid in the fatty acids, compared to glucose-grown cells. High cell densities were obtained in both batch (37 g L(-1), with 49% lipid in the biomass) and fed-batch (35 to 47 g L(-1), with 50 to 75% lipid in the biomass) cultures. The highest proportion of lipid in the biomass was observed in cultures given nitrogen during the batch phase but none with the feed. However, carbohydrate consumption was incomplete when the feed did not contain nitrogen and the highest total lipid and best substrate consumption were observed in cultures which received a constant low nitrogen supply. Lipid production in R. toruloides was lower from arabinose and mixed carbohydrates than from glucose or xylose. Although high biomass and lipid

  19. Micromachined piezoresistive inclinometer with oscillator-based integrated interface circuit and temperature readout

    Science.gov (United States)

    Dalola, Simone; Ferrari, Vittorio; Marioli, Daniele

    2012-03-01

    In this paper a dual-chip system for inclination measurement is presented. It consists of a MEMS (microelectromechanical system) piezoresistive accelerometer manufactured in silicon bulk micromachining and a CMOS (complementary metal oxide semiconductor) ASIC (application specific integrated circuit) interface designed for resistive-bridge sensors. The sensor is composed of a seismic mass symmetrically suspended by means of four flexure beams that integrate two piezoresistors each to detect the applied static acceleration, which is related to inclination with respect to the gravity vector. The ASIC interface is based on a relaxation oscillator where the frequency and the duty cycle of a rectangular-wave output signal are related to the fractional bridge imbalance and the overall bridge resistance of the sensor, respectively. The latter is a function of temperature; therefore the sensing element itself can be advantageously used to derive information for its own thermal compensation. DC current excitation of the sensor makes the configuration unaffected by wire resistances and parasitic capacitances. Therefore, a modular system results where the sensor can be placed remotely from the electronics without suffering accuracy degradation. The inclination measurement system has been characterized as a function of the applied inclination angle at different temperatures. At room temperature, the experimental sensitivity of the system results in about 148 Hz/g, which corresponds to an angular sensitivity around zero inclination angle of about 2.58 Hz deg-1. This is in agreement with finite element method simulations. The measured output fluctuations at constant temperature determine an equivalent resolution of about 0.1° at midrange. In the temperature range of 25-65 °C the system sensitivity decreases by about 10%, which is less than the variation due to the microsensor alone thanks to thermal compensation provided by the current excitation of the bridge and the positive

  20. Capacitive micromachined ultrasonic transducer for ultra-low pressure measurement: Theoretical study

    Directory of Open Access Journals (Sweden)

    Zhikang Li

    2015-12-01

    Full Text Available Ultra-low pressure measurement is necessary in many areas, such as high-vacuum environment monitoring, process control and biomedical applications. This paper presents a novel approach for ultra-low pressure measurement where capacitive micromachined ultrasonic transducers (CMUTs are used as the sensing elements. The working principle is based on the resonant frequency shift of the membrane under the applied pressure. The membranes of the biased CMUTs can produce a larger resonant frequency shift than the diaphragms with no DC bias in the state-of-the-art resonant pressure sensors, which contributes to pressure sensitivity improvement. The theoretical analysis and finite element method (FEM simulation were employed to study the relationship between the resonant frequency and the pressure. The results demonstrated excellent capability of the CMUTs for ultra-low pressure measurement. It is shown that the resonant frequency of the CMUT varies linearly with the applied pressure. A sensitivity of more than 6.33 ppm/Pa (68 kHz/kPa was obtained within a pressure range of 0 to 100 Pa when the CMUTs were biased at a DC voltage of 90% of the collapse voltage. It was also demonstrated that the pressure sensitivity can be adjusted by the DC bias voltage. In addition, the effects of air damping and ambient temperature on the resonant frequency were also studied. The effect of air damping is negligible for the pressures below 1000 Pa. To eliminate the temperature effect on the resonant frequency, a temperature compensating method was proposed.

  1. Harmonic Reduction in Capacitive Micromachined Ultrasonic Transducers by Gap Feedback Linearization

    Science.gov (United States)

    Satir, Sarp; Degertekin, F. Levent

    2012-01-01

    The nonlinear relationship between the electrical input signal and electrostatic force acting on the capacitive micromachined ultrasonic transducer (CMUT) membrane limits its harmonic imaging performance. Several input shaping methods were proposed in order to compensate for the nonlinearity originating from the electrostatic force dependence on the square of the applied voltage. Here we analyze harmonic generation in CMUTs with a time domain model. The model explains the basis of the input shaping methods and suggests that the nonlinearity due to gap dependence of the electrostatic force is also significant. It also suggests that the harmonic distortion in the output pressure can be eliminated by subharmonic AC only excitation of the CMUT in addition to scaling the input voltage with the instantaneous gap. This gap feedback configuration can be approximated by the simple addition of a series impedance to the CMUT capacitance. We analyze several types of series impedance feedback topologies for gap feedback linearization. We show that for subharmonic AC excitation while resistive and capacitive impedances result in a trade-off between input voltage and harmonic distortion for a desired pressure output, harmonic generation can be suppressed while increasing the Pa/V transmit sensitivity for proper series inductance and resistance feedback. We experimentally demonstrate the feedback method by reducing harmonic generation by 10dB for the same output pressure at the fundamental frequency by using a simple series resistor feedback with a CMUT operating at a center frequency of 3 MHz. The proposed methods also allow for utilization of the full CMUT gap for transmit operation and hence should be useful in high intensity ultrasonic applications in addition to harmonic imaging. PMID:22293735

  2. Optical micromachined ultrasound transducers (OMUT) - a new approach for high resolution imaging

    Science.gov (United States)

    Tadayon, M. A.; Ashkenazi, S.

    2013-03-01

    Piezoelectric ultrasound (US) transducers are at the heart of almost any ultrasonic medical imaging probe. However, their sensitivity and reliability severely degrade in applications requiring high frequency (>20 MHz) and small element size (CMUT) and optical sensing and generation of ultrasound are being investigated. In this paper we present our first steps in developing optical micromachined ultrasound transducers (OMUT) technology. OMUTs rely on microfabrication techniques to construct micron-size air cavities capped by an elastic membrane. The membrane functions as the active ultrasound transmitter and receiver. We will describe the design and testing of prototype OMUT devices which implement a receive-only function. The cavity detector is an optical cavity which its top mirror is deflected under the application of pressure. The intensity of a reflected light beam is highly sensitive to displacement of the top membrane if the optical wavelength is at near-resonance condition. Therefore, US pulses can be detected by recording the reflected light intensity. The sensitivity of the device depends on the mechanical properties of the top membrane and optical characteristics of the optical cavity. The device was fabricated using SU8 as a structural material and gold as a mirror. We have developed a new bonding method to fabricate a sealed, low roughness, high quality optical cavity. The 60μm cavity with the 8.5 μm top membrane is tested in water with 25MHz ultrasound transducer. The NEP of the device for bandwidth of 28MHz was 9.25kPa. The optical cavity has a finesse of around 23.

  3. Air-coupled MUMPs capacitive micromachined ultrasonic transducers with resonant cavities.

    Science.gov (United States)

    Octavio Manzanares, Alberto; Montero de Espinosa, Francisco

    2012-04-01

    This work reports performance improvements of air-coupled capacitive micromachined ultrasonic transducers (CMUTs) using resonant cavities. In order to perform this work, we have designed and manufactured a CMUT employing multi-user microelectromechanical systems (MEMS) processes (MUMPs). The transducer was designed using Helmholtz resonator principles. This was characterised by the dimensions of the cavity and several acoustic ports, which had the form of holes in the CMUT plate. The MUMPs process has the advantage of being low cost which allows the manufacture of economic prototypes. In this paper we show the effects of the resonant cavities and acoustic ports in CMUTs using laser Doppler vibrometry and acoustical measurements. We also use Finite Element (FE) simulations in order to support experimental measurements. The results show that it is possible to enhance the output pressure and bandwidth in air by tuning the resonance frequency of the plate (f(p)) with that of the Helmholtz resonator (f(H)). The experimental measurements show the plate resonance along with an additional resonance in the output pressure spectrum. This appears due to the effect of the new resonant cavities in the transducer. FE simulations show an increase of 11 dB in the output pressure with respect to that of a theoretical vacuum-sealed cavity MUMPs CMUT by properly tuning the transducer. The bandwidth has been also analyzed by calculating the mechanical Q factor of the tuned CMUT. This has been estimated as 4.5 compared with 7.75 for the vacuum-sealed cavity MUMPs CMUT. Copyright © 2011 Elsevier B.V. All rights reserved.

  4. Microwave design and analysis of a micromachined self-heating power sensor based on matching thermocouples

    Science.gov (United States)

    Zhang, Zhiqiang; Liao, Xiaoping

    2017-08-01

    Microwave performance is a basic index of the sensors used at microwave frequencies, but also affects the sensing output. For the purpose of low-loss microwave applications, it is important for different microwave sensors to develop microwave design. This paper presents the microwave design and analysis of a micromachined self-heating microwave power sensor in the GaAs MMIC process, where the microwave power is dissipated and converted into output thermovoltages by two matching thermocouples. A dc-blocking capacitor is connected to the thermocouples in series and used to avoid the output short-circuit. In order to characterize the microwave performance, an S-parameter model of this self-heating power sensor is established. Using the model, the effects of the capacitor and the thermocouples on the reflection loss are investigated under different microwave frequencies. To demonstrate the validity of the microwave model, the microwave performance of the self-heating sensor is simulated using an electromagnetic software. In the simulation, the relationship between the substrate membrane underneath the thermocouples and the reflection loss is analyzed. Measured reflection losses of the self-heating sensor are between  -15.5 to  -15.9 dB at 8-12 GHz. The measured results show good agreement with the microwave model and simulation, and the source of small deviations is discussed. The proposed microwave design and analysis contributes to achieving low reflection loss for the sensor, with the fact that more power is used to convert into the thermovoltages.

  5. A smart fully integrated micromachined separator with soft magnetic micro-pillar arrays for cell isolation

    Science.gov (United States)

    Dong, Tao; Su, Qianhua; Yang, Zhaochu; Zhang, Yulong; Egeland, Eirik B.; Gu, Dan D.; Calabrese, Paolo; Kapiris, Matteo J.; Karlsen, Frank; Minh, Nhut T.; Wang, K.; Jakobsen, Henrik

    2010-11-01

    A smart fully integrated micromachined separator with soft magnetic micro-pillar arrays has been developed and demonstrated, which can merely employ one independent lab-on-chip to realize cell isolation. The simulation, design, microfabrication and test for the new electromagnetic micro separator were executed. The simulation results of the electromagnetic field in the separator show that special soft magnetic micro-pillar arrays can amplify and redistribute the electromagnetic field generated by the micro-coils. The separator can be equipped with a strong magnetic field to isolate the target cells with a considerably low input current. The micro separator was fabricated by micro-processing technology. An electroplating bath was hired to deposit NiCo/NiFe to fabricate the micro-pillar arrays. An experimental system was set up to verify the function of the micro separator by isolating the lymphocytes, in which the human whole blood mixed with Dynabeads® FlowComp Flexi and monoclonal antibody MHCD2704 was used as the sample. The results show that the electromagnetic micro separator with an extremely low input current can recognize and capture the target lymphocytes with a high efficiency, the separation ratio reaching more than 90% at a lower flow rate. For the electromagnetic micro separator, there is no external magnetizing field required, and there is no extra cooling system because there is less Joule heat generated due to the lower current. The magnetic separator is totally reusable, and it can be used to separate cells or proteins with common antigens.

  6. System Error Compensation Methodology Based on a Neural Network for a Micromachined Inertial Measurement Unit

    Science.gov (United States)

    Liu, Shi Qiang; Zhu, Rong

    2016-01-01

    Errors compensation of micromachined-inertial-measurement-units (MIMU) is essential in practical applications. This paper presents a new compensation method using a neural-network-based identification for MIMU, which capably solves the universal problems of cross-coupling, misalignment, eccentricity, and other deterministic errors existing in a three-dimensional integrated system. Using a neural network to model a complex multivariate and nonlinear coupling system, the errors could be readily compensated through a comprehensive calibration. In this paper, we also present a thermal-gas MIMU based on thermal expansion, which measures three-axis angular rates and three-axis accelerations using only three thermal-gas inertial sensors, each of which capably measures one-axis angular rate and one-axis acceleration simultaneously in one chip. The developed MIMU (100 × 100 × 100 mm3) possesses the advantages of simple structure, high shock resistance, and large measuring ranges (three-axes angular rates of ±4000°/s and three-axes accelerations of ±10 g) compared with conventional MIMU, due to using gas medium instead of mechanical proof mass as the key moving and sensing elements. However, the gas MIMU suffers from cross-coupling effects, which corrupt the system accuracy. The proposed compensation method is, therefore, applied to compensate the system errors of the MIMU. Experiments validate the effectiveness of the compensation, and the measurement errors of three-axis angular rates and three-axis accelerations are reduced to less than 1% and 3% of uncompensated errors in the rotation range of ±600°/s and the acceleration range of ±1 g, respectively. PMID:26840314

  7. Modeling, Fabrication and Testing of a Customizable Micromachined Hotplate for Sensor Applications.

    Science.gov (United States)

    Tommasi, Alessio; Cocuzza, Matteo; Perrone, Denis; Pirri, Candido Fabrizio; Mosca, Roberto; Villani, Marco; Delmonte, Nicola; Zappettini, Andrea; Calestani, Davide; Marasso, Simone Luigi

    2016-12-30

    In the sensors field the active sensing material frequently needs a controlled temperature in order to work properly. In microsystems technology, micro-machined hotplates represent a platform consisting of a thin suspended membrane where the sensing material can be deposited, usually integrating electrical stimuli and temperature readout. The micro-hotplate ensures a series of advantages such as miniaturized size, fast response, high sensitivity, low power consumption and selectivity for chemical sensing. This work compares the coplanar and the buried approach for the micro-hotplate heaters design with the aim to optimize the fabrication process and to propose a guideline for the choice of the suitable design with respect to the applications. In particular, robust Finite Element Method (FEM) models are set up in order to predict the electrical and thermal behavior of the micro-hotplates. The multiphysics approach used for the simulation allows to match as close as possible the actual device to the predictive model: geometries, materials, physics have been carefully linked to the fabricated devices to obtain the best possible accuracy. The materials involved in the fabrication process are accurately selected in order to improve the yield of the process and the performance of the devices. The fabricated micro-hotplates are able to warm the active region up to 400 °C (with a corresponding power consumption equal to 250 mW @ 400 °C) with a uniform temperature distribution in the buried micro-hotplate and a controlled temperature gradient in the coplanar one. A response time of about 70 ms was obtained on the virtual model, which perfectly agrees with the one measured on the fabricated device. Besides morphological, electrical and thermal characterizations, this work includes reliability tests in static and dynamic modes.

  8. Modeling, Fabrication and Testing of a Customizable Micromachined Hotplate for Sensor Applications

    Directory of Open Access Journals (Sweden)

    Alessio Tommasi

    2016-12-01

    Full Text Available In the sensors field the active sensing material frequently needs a controlled temperature in order to work properly. In microsystems technology, micro-machined hotplates represent a platform consisting of a thin suspended membrane where the sensing material can be deposited, usually integrating electrical stimuli and temperature readout. The micro-hotplate ensures a series of advantages such as miniaturized size, fast response, high sensitivity, low power consumption and selectivity for chemical sensing. This work compares the coplanar and the buried approach for the micro-hotplate heaters design with the aim to optimize the fabrication process and to propose a guideline for the choice of the suitable design with respect to the applications. In particular, robust Finite Element Method (FEM models are set up in order to predict the electrical and thermal behavior of the micro-hotplates. The multiphysics approach used for the simulation allows to match as close as possible the actual device to the predictive model: geometries, materials, physics have been carefully linked to the fabricated devices to obtain the best possible accuracy. The materials involved in the fabrication process are accurately selected in order to improve the yield of the process and the performance of the devices. The fabricated micro-hotplates are able to warm the active region up to 400 °C (with a corresponding power consumption equal to 250 mW @ 400 °C with a uniform temperature distribution in the buried micro-hotplate and a controlled temperature gradient in the coplanar one. A response time of about 70 ms was obtained on the virtual model, which perfectly agrees with the one measured on the fabricated device. Besides morphological, electrical and thermal characterizations, this work includes reliability tests in static and dynamic modes.

  9. Preclinical Testing of Frequency-Tunable Capacitive Micromachined Ultrasonic Transducer Probe Prototypes.

    Science.gov (United States)

    Pekař, Martin; Kolen, Alexander F; Belt, Harm; van Heesch, Frank; Mihajlović, Nenad; Hoefer, Imo E; Szili-Török, Tamas; Vos, Hendrik J; Bosch, Johan G; van Soest, Gijs; van der Steen, Antonius F W

    2017-09-01

    In intracardiac echocardiography (ICE) it may be beneficial to generate ultrasound images acquired at multiple frequencies, having the possibility of high penetration or high-resolution imaging in a single device. The objective of the presented work is to test two frequency-tunable probe prototypes in a preclinical setting: a rigid probe having a diameter of 11 mm and a new flexible and steerable 12-Fr ICE catheter. Both probes feature a forward-looking 32-element capacitive micromachined ultrasonic transducer array (aperture of 2 × 2 mm 2 ) operated in collapse mode, which allows for frequency tuning in the 6-MHz-18-MHz range. The rigid probe prototype is tested ex vivo in a passive heart platform. Images of an aortic valve acquired in high-penetration (6 MHz), generic (12 MHz) and high-resolution (18 MHz) mode combine satisfying image quality and penetration depth between 2.5 cm and 10 cm. The ICE catheter prototype is tested in vivo using a porcine animal model. Images of an aortic valve are acquired in the 3 imaging modes with the ICE catheter placed in an ascending aorta at multiple depths. It was found that the combination of the forward-looking design and frequency-tuning capability allows visualizing intracardiac structures of various sizes at different distances relative to the catheter tip, providing both wide overviews and detailed close-ups. Copyright © 2017 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

  10. Micromachining of commodity plastics by proton beam writing and fabrication of spatial resolution test-chart for neutron radiography

    International Nuclear Information System (INIS)

    Sakai, T.; Yasuda, R.; Iikura, H.; Nojima, T.; Matsubayashi, M.; Kada, W.; Kohka, M.; Satoh, T.; Ohkubo, T.; Ishii, Y.; Takano, K.

    2013-01-01

    Proton beam writing is a direct-write technique and a promising method for the micromachining of commodity plastics such as acrylic resins. Herein, we describe the fabrication of microscopic devices made from a relatively thick (∼75 μm) acrylic sheet using proton beam writing. In addition, a software package that converts image pixels into coordinates data was developed, and the successful fabrication of a very fine jigsaw puzzle was achieved. The size of the jigsaw puzzle pieces was 50 × 50 μm. For practical use, a prototype of a line and space test-chart was also successfully fabricated for the determination of spatial resolution in neutron radiography

  11. Micromachined silicon cantilevers with integrated high-frequency magnetoimpedance sensors for simultaneous strain and magnetic field detection

    Science.gov (United States)

    Buettel, G.; Joppich, J.; Hartmann, U.

    2017-12-01

    Giant magnetoimpedance (GMI) measurements in the high-frequency regime utilizing a coplanar waveguide with an integrated Permalloy multilayer and micromachined on a silicon cantilever are reported. The fabrication process is described in detail. The aspect ratio of the magnetic multilayer in the magnetoresistive and magnetostrictive device was varied. Tensile strain and compressive strain were applied. Vector network analyzer measurements in the range from the skin effect to ferromagnetic resonance confirm the technological potential of GMI-based micro-electro-mechanical devices for strain and magnetic field sensing applications. The strain-impedance gauge factor was quantified by finite element strain calculations and reaches a maximum value of almost 200.

  12. Shell of Planet Earth – Global Batch Bioreactor.

    Czech Academy of Sciences Publication Activity Database

    Hanika, Jiří; Šolcová, Olga; Kaštánek, P.

    2017-01-01

    Roč. 40, č. 11 (2017), s. 1959-1965 ISSN 0930-7516 R&D Projects: GA TA ČR TE01020080 Institutional support: RVO:67985858 Keywords : critical raw materials * global batch bioreactor * planet earth Subject RIV: CI - Industrial Chemistry, Chemical Engineering OBOR OECD: Chemical process engineering Impact factor: 2.051, year: 2016

  13. Batch arrival discrete time queue with gated vacation system ...

    African Journals Online (AJOL)

    A class of single server vacation queues, which have batch arrivals and single server, is considered in discrete time. Here the server goes on vacation of random length as soon as the system becomes empty. On return from vacation, if he finds any customers waiting in the queue, the server starts serving the customers one ...

  14. Medium optimization for protopectinase production by batch culture of

    African Journals Online (AJOL)

    Medium optimization for protopectinase production by batch culture of. C Fan, Z Liu, L Yao. Abstract. Optimization of medium compositions for protopectinase production by Aspergillus terreus in submerged culture was carried out. The medium components having significant effect on protopectinase production were reported ...

  15. DEVELOPMENT OF AN AUTOMATED BATCH-PROCESS SOLAR ...

    African Journals Online (AJOL)

    One of the shortcomings of solar disinfection of water (SODIS) is the absence of a feedback mechanism indicating treatment completion. This work presents the development of an automated batch-process water disinfection system aimed at solving this challenge. Locally sourced materials in addition to an Arduinomicro ...

  16. Quality control for 12 batch of DTPA-Sn

    International Nuclear Information System (INIS)

    Isaac, M.; Gamboa, R.; Leyva, R.; Hernandez, I.; Turino, D.

    1994-01-01

    The quality control is carry out at 12 batch of DTPA-Sn for labeling with 99 m Tc. The instrumental methods of analysis and control charts were discussed in order to find a warranty time for the product. (author). 2 refs, 3 figs, 1 tab

  17. Development of Production Control in Small Batch Production

    Directory of Open Access Journals (Sweden)

    Németh Péter

    2016-01-01

    Full Text Available Our aim with this paper is to develop a new performance measurement and control system for small batch production in the automotive industry. For this reason, we present our previous research results for warehouse performance measurement and adopt its methodology to production control. The proposed method is based on artificial intelligence (neural networks.

  18. Sequencing for Batch Production in a Group Flowline Machine Shop ...

    African Journals Online (AJOL)

    The purpose of the paper is to develop a useful technique for sequencing batches of components through machine shops arranged under the group flowline production system. The approach is to apply a modified version of Petrov's group flowline technique for machining components which follow a unidirectional route.

  19. Comparison of neptunium sorption results using batch and column techniques

    International Nuclear Information System (INIS)

    Triay, I.R.; Furlano, A.C.; Weaver, S.C.; Chipera, S.J.; Bish, D.L.

    1996-08-01

    We used crushed-rock columns to study the sorption retardation of neptunium by zeolitic, devitrified, and vitric tuffs typical of those at the site of the potential high-level nuclear waste repository at Yucca Mountain, Nevada. We used two sodium bicarbonate waters (groundwater from Well J-13 at the site and water prepared to simulate groundwater from Well UE-25p No. 1) under oxidizing conditions. It was found that values of the sorption distribution coefficient, Kd, obtained from these column experiments under flowing conditions, regardless of the water or the water velocity used, agreed well with those obtained earlier from batch sorption experiments under static conditions. The batch sorption distribution coefficient can be used to predict the arrival time for neptunium eluted through the columns. On the other hand, the elution curves showed dispersivity, which implies that neptunium sorption in these tuffs may be nonlinear, irreversible, or noninstantaneous. As a result, use of a batch sorption distribution coefficient to calculate neptunium transport through Yucca Mountain tuffs would yield conservative values for neptunium release from the site. We also noted that neptunium (present as the anionic neptunyl carbonate complex) never eluted prior to tritiated water, which implies that charge exclusion does not appear to exclude neptunium from the tuff pores. The column experiments corroborated the trends observed in batch sorption experiments: neptunium sorption onto devitrified and vitric tuffs is minimal and sorption onto zeolitic tuffs decreases as the amount of sodium and bicarbonate/carbonate in the water increases

  20. On energy optimisation in multipurpose batch plants using heat storage

    CSIR Research Space (South Africa)

    Majozi, T

    2010-10-01

    Full Text Available The use of heat integration in multipurpose batch plants to minimise energy usage has been in the literature for more than two decades. Direct heat integration may be exploited when the heat source and heat sink processes are active over a common...

  1. Batch immunoextraction method for efficient purification of aromatic cytokinins

    Czech Academy of Sciences Publication Activity Database

    Hauserová, Eva; Swaczynová, Jana; Doležal, Karel; Lenobel, René; Popa, Igor; Hajdúch, M.; Vydra, D.; Fuksová, Květoslava; Strnad, Miroslav

    2005-01-01

    Roč. 1100, č. 1 (2005), s. 116-125 ISSN 0021-9673 R&D Projects: GA AV ČR IBS4055304 Institutional research plan: CEZ:AV0Z50380511; MSM6198959216 Keywords : antibody * 6-benzylaminopurine * batch immunoextraction Subject RIV: ED - Physiology Impact factor: 3.096, year: 2005

  2. Tier 3 batch system data locality via managed caches

    Science.gov (United States)

    Fischer, Max; Giffels, Manuel; Jung, Christopher; Kühn, Eileen; Quast, Günter

    2015-05-01

    Modern data processing increasingly relies on data locality for performance and scalability, whereas the common HEP approaches aim for uniform resource pools with minimal locality, recently even across site boundaries. To combine advantages of both, the High- Performance Data Analysis (HPDA) Tier 3 concept opportunistically establishes data locality via coordinated caches. In accordance with HEP Tier 3 activities, the design incorporates two major assumptions: First, only a fraction of data is accessed regularly and thus the deciding factor for overall throughput. Second, data access may fallback to non-local, making permanent local data availability an inefficient resource usage strategy. Based on this, the HPDA design generically extends available storage hierarchies into the batch system. Using the batch system itself for scheduling file locality, an array of independent caches on the worker nodes is dynamically populated with high-profile data. Cache state information is exposed to the batch system both for managing caches and scheduling jobs. As a result, users directly work with a regular, adequately sized storage system. However, their automated batch processes are presented with local replications of data whenever possible.

  3. A recirculating incubation system for hatching small batches of fish ...

    African Journals Online (AJOL)

    This paper describes the design, construction and evaluation of the capacity of a re-circulating incubation system for hatching small batches of fish eggs. ... Water flowed out of the incubation unit through a small section of glass and then plastic tubing inserted through a second hole in the rubber stopper to a PVC drain ...

  4. Spore survival during batch dry rendering of abattoir waste.

    Science.gov (United States)

    Lowry, P D; Fernando, T; Gill, C O

    1979-01-01

    Normal batch dry rendering practice does not ensure sterile products, because bacterial spores are protected against thermal denaturation by the high fat-low water content environment which results from drying the materials at temperatures below those required for sterilization. PMID:117753

  5. Adaptation to high throughput batch chromatography enhances multivariate screening.

    Science.gov (United States)

    Barker, Gregory A; Calzada, Joseph; Herzer, Sibylle; Rieble, Siegfried

    2015-09-01

    High throughput process development offers unique approaches to explore complex process design spaces with relatively low material consumption. Batch chromatography is one technique that can be used to screen chromatographic conditions in a 96-well plate. Typical batch chromatography workflows examine variations in buffer conditions or comparison of multiple resins in a given process, as opposed to the assessment of protein loading conditions in combination with other factors. A modification to the batch chromatography paradigm is described here where experimental planning, programming, and a staggered loading approach increase the multivariate space that can be explored with a liquid handling system. The iterative batch chromatography (IBC) approach is described, which treats every well in a 96-well plate as an individual experiment, wherein protein loading conditions can be varied alongside other factors such as wash and elution buffer conditions. As all of these factors are explored in the same experiment, the interactions between them are characterized and the number of follow-up confirmatory experiments is reduced. This in turn improves statistical power and throughput. Two examples of the IBC method are shown and the impact of the load conditions are assessed in combination with the other factors explored. Copyright © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. An analysis of DTP- associated reactions by manufacturer, batch ...

    African Journals Online (AJOL)

    Merieux J5497 or SAIMR F08609. Methods of randomisation varied slightly between the two clinic groups in order to minimise clinic disruption. DTP dose numbers and batches were recorded on clinic cards to ensure vaccination with the same ...

  7. A storage assignment model for batch preparation in process industries

    NARCIS (Netherlands)

    Ashayeri, J.; Selen, W.

    2013-01-01

    Purpose – The purpose of this paper is to develop new model formulation for reducing the workload in pre‐batching at a manufacturer of flavors and fragrances, by optimally assigning ingredients to different storage types, taking into account past usage of ingredients and several restrictions about

  8. Synthesis of zero effluent multipurpose batch processes using effective scheduling

    CSIR Research Space (South Africa)

    Gouws, JF

    2008-06-01

    Full Text Available the scheduling of operations in the synthesis phase. The mathematically based method presented in this paper deals with the synthesis of a batch plant operating in the fashion mentioned above. The method determines the optimal size and number of processing...

  9. Comparative Batch and Column Evaluation of Thermal and Wet ...

    African Journals Online (AJOL)

    batch adsorption experiments and continous flow (fixed bed) column experiment to study the mechanism of dye removal by the commercial ... compared with those obtained for thermal regeneration method (qmax = 61.73mgg-1) and wet oxidative method (qmax .... Carbon hardness was determined using a wet attrition test ...

  10. Risk-based Methodology for Validation of Pharmaceutical Batch Processes.

    Science.gov (United States)

    Wiles, Frederick

    2013-01-01

    In January 2011, the U.S. Food and Drug Administration published new process validation guidance for pharmaceutical processes. The new guidance debunks the long-held industry notion that three consecutive validation batches or runs are all that are required to demonstrate that a process is operating in a validated state. Instead, the new guidance now emphasizes that the level of monitoring and testing performed during process performance qualification (PPQ) studies must be sufficient to demonstrate statistical confidence both within and between batches. In some cases, three qualification runs may not be enough. Nearly two years after the guidance was first published, little has been written defining a statistical methodology for determining the number of samples and qualification runs required to satisfy Stage 2 requirements of the new guidance. This article proposes using a combination of risk assessment, control charting, and capability statistics to define the monitoring and testing scheme required to show that a pharmaceutical batch process is operating in a validated state. In this methodology, an assessment of process risk is performed through application of a process failure mode, effects, and criticality analysis (PFMECA). The output of PFMECA is used to select appropriate levels of statistical confidence and coverage which, in turn, are used in capability calculations to determine when significant Stage 2 (PPQ) milestones have been met. The achievement of Stage 2 milestones signals the release of batches for commercial distribution and the reduction of monitoring and testing to commercial production levels. Individuals, moving range, and range/sigma charts are used in conjunction with capability statistics to demonstrate that the commercial process is operating in a state of statistical control. The new process validation guidance published by the U.S. Food and Drug Administration in January of 2011 indicates that the number of process validation batches

  11. A Three-Dimensional Enormous Surface Area Aluminum Microneedle Array with Nanoporous Structure

    OpenAIRE

    Chen, Po Chun; Hsieh, Sheng Jen; Chen, Chien Chon; Zou, Jun

    2013-01-01

    We proposed fabricating an aluminum microneedle array with a nanochannel structure on the surface by combining micromachining, electrolyte polishing, and anodization methods. The microneedle array provides a three-dimensional (3D) structure that possesses several hundred times more surface area than a traditional nanochannel template. Therefore, the microneedle array can potentially be used in many technology applications. This 3D microneedle array device can not only be used for painless inj...

  12. Supercritical Water Gasification of Biomass in a Ceramic Reactor: Long-Time Batch Experiments

    Directory of Open Access Journals (Sweden)

    Daniele Castello

    2017-10-01

    Full Text Available Supercritical water gasification (SCWG is an emerging technology for the valorization of (wet biomass into a valuable fuel gas composed of hydrogen and/or methane. The harsh temperature and pressure conditions involved in SCWG (T > 375 °C, p > 22 MPa are definitely a challenge for the manufacturing of the reactors. Metal surfaces are indeed subject to corrosion under hydrothermal conditions, and expensive special alloys are needed to overcome such drawbacks. A ceramic reactor could be a potential solution to this issue. Finding a suitable material is, however, complex because the catalytic effect of the material can influence the gas yield and composition. In this work, a research reactor featuring an internal alumina inlay was utilized to conduct long-time (16 h batch tests with real biomasses and model compounds. The same experiments were also conducted in batch reactors made of stainless steel and Inconel 625. The results show that the three devices have similar performance patterns in terms of gas production, although in the ceramic reactor higher yields of C2+ hydrocarbons were obtained. The SEM observation of the reacted alumina surface revealed a good resistance of such material to supercritical conditions, even though some intergranular corrosion was observed.

  13. Achievement report for fiscal 1996 on the research and development of micromachine technology. Development of advanced-function maintenance technology for power generation facilities; 1996 nendo micromachine gijutsu no kenkyu kaihatsu seika hokokusho. Hatsuden shisetsuyo kokino maintenance gijutsu kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    Technologies for integrating functions are studied for a self-propelled surroundings recognition system that travels in a small-diameter tube at power generation facilities. Parameters are analyzed, and piezoelectric locomotion devices are reduced in size. A disk shape microantenna is experimentally built and evaluated, which is for realizing energy supply and communication by means of microwaves. Studies are conducted to improve the performance of optical energy transmission devices and to realize their systematization. Basic specifications are established for the embodiment of CCD (charge coupled device) microcameras to be installed. A high-efficiency, high-reliability micromachine system is constructed, in which multiple machines coordinate with each other for the exterior inspection of groups of small-diameter tubes. Devices which are capable of driving, deceleration, and propulsion prove to be feasible. Basic specifications are established for microconnectors to connect, separate, and combine multiple machines as occasion calls. Also discussed is the development of a micromachine for tube interior check and repair which operates making use of the inspection hole enabling tube interior check and repair without the need of disassembling the equipment to be repaired.

  14. MASS PRODUCTION OF THE BENEFICIAL NEMATODE STEINERNEMA CARPOCAPSAE UTILIZING A FED-BATCH CULTURING PROCESS

    OpenAIRE

    Leonard D. Holmes; Floyd L. Inman III; Sivanadane Mandjiny; Rinu Kooliyottil; Devang Upadhyay

    2013-01-01

    The present study deals with the batch and fed-batch mass production of Steinernema carpocapsae. S. carpocapsae is an entomoparasitic nematode that is used as a biological control agent of soil-borne crop insect pests. The ability and efficiency of fed-batch culture process was successful through the utilization of the nematode’s bacterial symbiont Xenorhabdus nematophila. Results from the fed-batch process were compared to those obtain from the standard batch process. The fed-batch process s...

  15. Glucoamylase production in batch, chemostat and fed-batch cultivations by an industrial strain of Aspergillus niger

    DEFF Research Database (Denmark)

    Pedersen, Henrik; Beyer, Michael; Nielsen, Jens

    2000-01-01

    growth rate of the fungus were independent of pH when grown in batch cultivations. The specific glucoamylase productivity increased linearly with the specific growth rate in the range 0-0.1 h(-1) and was constant in the range 0.1-0.2 h(-1) Maltose and maltodextrin were non-inducing carbon sources...

  16. Micromachined silicon acoustic delay line with improved structural stability and acoustic directivity for real-time photoacoustic tomography

    Science.gov (United States)

    Cho, Young; Kumar, Akhil; Xu, Song; Zou, Jun

    2017-03-01

    Recent studies have shown that micromachined silicon acoustic delay lines can provide a promising solution to achieve real-time photoacoustic tomography without the need for complex transducer arrays and data acquisition electronics. However, as its length increases to provide longer delay time, the delay line becomes more vulnerable to structural instability due to reduced mechanical stiffness. In addition, the small cross-section area of the delay line results in a large acoustic acceptance angle and therefore poor directivity. To address these two issues, this paper reports the design, fabrication, and testing of a new silicon acoustic delay line enhanced with 3D printed polymer micro linker structures. First, mechanical deformation of the silicon acoustic delay line (with and without linker structures) under gravity was simulated by using finite element method. Second, the acoustic crosstalk and acoustic attenuation caused by the polymer micro linker structures were evaluated with both numerical simulation and ultrasound transmission testing. The result shows that the use of the polymer micro linker structures significantly improves the structural stability of the silicon acoustic delay lines without creating additional acoustic attenuation and crosstalk. In addition, a new tapered design for the input terminal of the delay line was also investigate to improve its acoustic directivity by reducing the acoustic acceptance angle. These two improvements are expected to provide an effective solution to eliminate current limitations on the achievable acoustic delay time and out-of-plane imaging resolution of micromachined silicon acoustic delay line arrays.

  17. Concomitant reduction of lactate and ammonia accumulation in fed-batch cultures: Impact on glycoprotein production and quality.

    Science.gov (United States)

    Karengera, Eric; Robotham, Anna; Kelly, John; Durocher, Yves; De Crescenzo, Gregory; Henry, Olivier

    2018-01-05

    Lactate and ammonia accumulation is a major factor limiting the performance of fed-batch strategies for mammalian cell culture processes. In addition to the detrimental effects of these by-products on production yield, ammonia also contributes to recombinant glycoprotein quality deterioration. In this study, we tackled the accumulation of these two inhibiting metabolic wastes by culturing in glutamine-free fed-batch cultures an engineered HEK293 cell line displaying an improved central carbon metabolism. Batch cultures highlighted the ability of PYC2-overexpressing HEK293 cells to grow and sustain a relatively high viability in absence of glutamine without prior adaptation to the culture medium. In fed-batch cultures designed to maintain glucose at high concentration by daily feeding a glutamine-free concentrated nutrient feed, the maximum lactate and ammonia concentrations did not exceed 5 and 1 mM, respectively. In flask, this resulted in more than a 2.5-fold increase in IFNα2b titer in comparison to the control glutamine-supplied fed-batch. In bioreactor, this strategy led to similar reductions in lactate and ammonia accumulation and an increase in IFNα2b production. Of utmost importance, this strategy did not affect IFNα2b quality with respect to sialylation and glycoform distribution as confirmed by surface plasmon resonance biosensing and LC-MS, respectively. Our strategy thus offers an attractive and simple approach for the development of efficient cell culture processes for the mass production of high-quality therapeutic glycoproteins. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 2018. © 2018 American Institute of Chemical Engineers.

  18. Acoustical imaging using capacitive micromachined ultrasonic transducer arrays: Devices, circuits, and systems

    Science.gov (United States)

    Oralkan, Omer

    Integrated circuit technologies have had a great impact on the development of medical devices. Diagnostic imaging systems have benefited tremendously from the improvements in integrated circuits. One of the recent examples of this interaction between the two disciplines occurred in the area of ultrasonic imaging. The ability to build structures with dimensions in the submicron range enabled the realization of an almost a century old idea: Capacitive ultrasonic transducers. The major advantages of this transducer technology are ease of fabrication, potential for integration with supporting electronic circuits and improved bandwidth and sensitivity. This dissertation analyzes the viability of capacitive micromachined ultrasonic transducers (CMUTs) for practical imaging applications. This analysis is conducted by a detailed characterization effort, and by demonstrating both 2-D and 3-D images. Acoustical performance of 1-D and 2-D CMUT arrays fabricated using silicon integrated circuit technology has been experimentally characterized for transmit and receive modes, and the results are found to be in good agreement with the theoretical expectations. Both 2-D and 3-D images have been demonstrated. The distinctive features of CMUTs manifest themselves in the results of the characterization experiments and also in the resulting images. This dissertation also describes a general approach to design integrated front-end circuits for ultrasonic imaging and demonstrates basic circuit blocks for use in integrated systems along with CMUT arrays. The integration of the ultrasonic transducer arrays with supporting electronics not only reduces the cost and complexity of the system but also provides several advantages such as reduced parasitics, improved sensitivity, and a compact design with a reduced number of external interconnects. In this study, a custom integrated circuit comprising a pulse driver, a transmit/receive (T/R) switch and a wideband preamplifier has been fabricated

  19. Fabrication and characterization of a smart epitaxial piezoelectric micromachined ultrasonic transducer

    Energy Technology Data Exchange (ETDEWEB)

    Ozaki, Katsuya [Department of Electrical and Electronic Information Engg, Toyohashi University of Technology, Toyohashi, Aichi 441-8580 (Japan); Matin, Abdul, E-mail: matin.md.a@gmail.com [Department of Glass and Ceramic Engineering, Bangladesh University of Engg and Tech (BUET), Dhaka 1000 (Bangladesh); Numata, Yasuyuki [Department of Electrical and Electronic Information Engg, Toyohashi University of Technology, Toyohashi, Aichi 441-8580 (Japan); Akai, Daisuke [Electronics-Inspired Interdisciplinary Research Institute (EIIRIS), Toyohashi University of Technology Toyohashi, Toyohahsi, Aichi 441-8580 (Japan); Sawada, Kazuaki; Ishida, Makoto [Department of Electrical and Electronic Information Engg, Toyohashi University of Technology, Toyohashi, Aichi 441-8580 (Japan); Electronics-Inspired Interdisciplinary Research Institute (EIIRIS), Toyohashi University of Technology Toyohashi, Toyohahsi, Aichi 441-8580 (Japan)

    2014-12-15

    Highlights: • Highly [1 1 1] orientated functional PZT(1 1 1) thin film was grown on n-Si(1 1 1)/γ-Al{sub 2}O{sub 3}(1 1 1)/SrRuO{sub 3}(1 1 1). • Device performance of pMUT was studied using both experiment and modeling. • Material anisotropy played a significant role in the shifting of resonant frequency • pMUT shows high sensitivity for the transmission of ultrasonic pulses. • Successful realization of a piezoelectric ultrasonic transducer (pMUT) array. - Abstract: A novel piezoelectric micromachined ultrasonic transducer (pMUT) array was designed and fabricated using epitaxially grown functional Pb(Zr{sub 0.52}Ti{sub 0.48})O{sub 3} (PZT) thin film on Si(1 1 1)/γ-Al{sub 2}O{sub 3}(1 1 1)/SrRuO{sub 3}(1 1 1) substrate for biomedical applications. The crystallographic orientation of PZT film was controlled by the incorporation of epitaxial γ-Al{sub 2}O{sub 3} film on Si substrate. Modal shape of pMUT was analyzed employing advanced 3D finite element modeling taking the crystallographic anisotropy of materials and the properties of immersed medium (air or water) into account. Eigenfrequency with mode shapes has shown to have significant influence on transmitting-receiving characteristics of pMUT. Modal shapes of pMUT were also quantitatively determined using Laser Doppler Vibratometry (LDV). An excellent correlation was obtained between computational and experimental results. A significantly high sensitivity of 3.9 μV/kPa was obtained in an under-water ultrasonic wave transmission experiment conducted using fabricated pMUT as wave transmitter and a commercial transducer as receiver at a fundamental frequency of 1.20 MHz. Advanced FE computation thus serves as a tool to a priori optimize device structure for the successful transmission of ultrasonic waves with sufficient power to generate high resolution 3D imaging.

  20. Optimal Operation of Industrial Batch Crystallizers : A Nonlinear Model-based Control Approach

    NARCIS (Netherlands)

    Mesbah, A.

    2010-01-01

    Batch crystallization is extensively employed in the chemical, pharmaceutical, and food industries to separate and purify high value-added chemical substances. Despite their widespread application, optimal operation of batch crystallizers is particularly challenging. The difficulties primarily

  1. Selecting local constraint for alignment of batch process data with dynamic time warping

    DEFF Research Database (Denmark)

    Spooner, Max Peter; Kold, David; Kulahci, Murat

    2017-01-01

    observation number for every batch. Dynamic time warping has been shown to be an effective method for meeting these objectives. This is based on a dynamic programming algorithm that aligns a batch to a reference batch, by stretching and compressing its local time dimension. The resulting ”warping function......There are two key reasons for aligning batch process data. The first is to obtain same-length batches so that standard methods of analysis may be applied, whilst the second reason is to synchronise events that take place during each batch so that the same event is associated with the same......” may be interpreted as a progress signature of the batch which may be appended to the aligned data for further analysis. For the warping function to be a realistic reflection of the progress of a batch, it is necessary to impose some constraints on the dynamic time warping algorithm, to avoid...

  2. Mathematical technique for the design of near-zero-effluent batch processess

    CSIR Research Space (South Africa)

    Gouws, JF

    2008-07-01

    Full Text Available Wastewater minimisation in chemical processes has always been the privilege of continuous rather than batch plants. However, this situation is steadily changing, since batch plants have a tendency to generate much more toxic effluent compared...

  3. Heat integration in multipurpose batch plants using a robust scheduling framework

    CSIR Research Space (South Africa)

    Seid, ER

    2014-07-01

    Full Text Available Energy saving is becoming increasingly important in batch processing facilities. Multipurpose batch plants have become more popular than ever in the processing environment due to their inherent flexibility and adaptability to market conditions, even...

  4. On Bottleneck Product Rate Variation Problem with Batching

    Directory of Open Access Journals (Sweden)

    Shree Khadka

    2013-07-01

    Full Text Available The product rate variation problem minimizes the variation in the rate at which different models of a common base product are produced on the assembly lines with the assumption of negligible switch-over cost and unit processing time for each copy of each model. The assumption of significant setup and arbitrary processing times forces the problem to be a two phase problem. The first phase determines the size and the number of batches and the second one sequences the batches of models. In this paper, the bottleneck case i.e. the min-max case of the problem with a generalized objective function is formulated. A Pareto optimal solution is proposed and a relation between optimal sequences for the problem with different objective functions is investigated.

  5. Integration of Grid and Local Batch Resources at DESY

    Science.gov (United States)

    Beyer, Christoph; Finnern, Thomas; Gellrich, Andreas; Hartmann, Thomas; Kemp, Yves; Lewendel, Birgit

    2017-10-01

    As one of the largest resource centres DESY has to support differing work flows of users from various scientific backgrounds. Users can be for one HEP experiments in WLCG or Belle II as well as local HEP users but also physicists from other fields as photon science or accelerator development. By abandoning specific worker node setups in favour of generic flat nodes with middleware resources provided via CVMFS, we gain flexibility to subsume different use cases in a homogeneous environment. Grid jobs and the local batch system are managed in a HTCondor based setup, accepting pilot, user and containerized jobs. The unified setup allows dynamic re-assignment of resources between the different use cases. Monitoring is implemented on global batch system metrics as well as on a per job level utilizing corresponding cgroup information.

  6. APPLICATION OF MODEL PREDICTIVE CONTROL TO BATCH POLYMERIZATION REACTOR

    Directory of Open Access Journals (Sweden)

    N.M. Ghasem

    2006-06-01

    Full Text Available The absence of a stable operational state in polymerization reactors that operates in batches is factor that determine the need of a special control system. In this study, advanced control methodology is implemented for controlling the operation of a batch polymerization reactor for polystyrene production utilizingmodel predictive control. By utilizing a model of the polymerization process, the necessary operational conditions were determined for producing the polymer within the desired characteristics. The maincontrol objective is to bring the reactor temperature to its target temperature as rapidly as possible with minimal temperature overshoot. Control performance for the proposed method is encouraging. It has been observed that temperature overshoot can be minimized by the proposed method with the use of both reactor and jacket energy balance for reactor temperature control.

  7. Continuous Heterogeneous Photocatalysis in Serial Micro-Batch Reactors.

    Science.gov (United States)

    Pieber, Bartholomäus; Shalom, Menny; Antonietti, Markus; Seeberger, Peter H; Gilmore, Kerry

    2018-01-29

    Solid reagents, leaching catalysts, and heterogeneous photocatalysts are commonly employed in batch processes but are ill-suited for continuous-flow chemistry. Heterogeneous catalysts for thermal reactions are typically used in packed-bed reactors, which cannot be penetrated by light and thus are not suitable for photocatalytic reactions involving solids. We demonstrate that serial micro-batch reactors (SMBRs) allow for the continuous utilization of solid materials together with liquids and gases in flow. This technology was utilized to develop selective and efficient fluorination reactions using a modified graphitic carbon nitride heterogeneous catalyst instead of costly homogeneous metal polypyridyl complexes. The merger of this inexpensive, recyclable catalyst and the SMBR approach enables sustainable and scalable photocatalysis. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. JAVA Implementation of the Batched iLab Shared Architecture

    Directory of Open Access Journals (Sweden)

    Lenard Payne

    2013-04-01

    Full Text Available The MIT iLab Shared Architecture is limited currently to running on the Microsoft Windows platform. A JAVA implementation of the Batched iLab Shared Architecture has been developed that can be used on other operating systems and still interoperate with the existing Microsoft .NET web services of MIT’s iLab ServiceBroker. The Batched iLab Shared Architecture has been revised and separates the Labserver into a LabServer that handles experiment management and a LabEquipment that handles experiment execution. The JAVA implementation provides a 3-tier code development model that allows code to be reused and to develop only the code that is specific to each experiment.

  9. Recipe-Based Batch Control Using High-Level Grafchart

    OpenAIRE

    Johnsson, Charlotta

    1997-01-01

    High-Level Grafchart is a graphical programming language for control of sequential processes. Sequential control is important in all kinds of industries: discrete, continuous and batch. Sequential elements show up both on the local control level and on the supervisory control level. High-Level Grafchart combines the graphical syntax of Grafcet/SFC with high-level programming language constructs and ideas from High-Level Petri Nets. High-Level Grafchart can be used to control sequential proces...

  10. Using Simulation for Scheduling and Rescheduling of Batch Processes

    OpenAIRE

    Girish Joglekar

    2017-01-01

    The problem of scheduling multiproduct and multipurpose batch processes has been studied for more than 30 years using math programming and heuristics. In most formulations, the manufacturing recipes are represented by simplified models using state task network (STN) or resource task network (RTN), transfers of materials are assumed to be instantaneous, constraints due to shared utilities are often ignored, and scheduling horizons are kept small due to the limits on the problem size that can b...

  11. Integration of virtualized worker nodes in standard batch systems

    International Nuclear Information System (INIS)

    Buege, Volker; Kunze, Marcel; Oberst, Oliver; Quast, Guenter; Scheurer, Armin; Hessling, Hermann; Kemp, Yves; Synge, Owen

    2010-01-01

    Current experiments in HEP only use a limited number of operating system flavours. Their software might only be validated on one single OS platform. Resource providers might have other operating systems of choice for the installation of the batch infrastructure. This is especially the case if a cluster is shared with other communities, or communities that have stricter security requirements. One solution would be to statically divide the cluster into separated sub-clusters. In such a scenario, no opportunistic distribution of the load can be achieved, resulting in a poor overall utilization efficiency. Another approach is to make the batch system aware of virtualization, and to provide each community with its favoured operating system in a virtual machine. Here, the scheduler has full flexibility, resulting in a better overall efficiency of the resources. In our contribution, we present a lightweight concept for the integration of virtual worker nodes into standard batch systems. The virtual machines are started on the worker nodes just before jobs are executed there. No meta-scheduling is introduced. We demonstrate two prototype implementations, one based on the Sun Grid Engine (SGE), the other using Maui/Torque as a batch system. Both solutions support local job as well as Grid job submission. The hypervisors currently used are Xen and KVM, a port to another system is easily envisageable. To better handle different virtual machines on the physical host, the management solution VmImageManager is developed. We will present first experience from running the two prototype implementations. In a last part, we will show the potential future use of this lightweight concept when integrated into high-level (i.e. Grid) work-flows.

  12. Adsorption of Arsenite onto Kemiron in a batch system

    African Journals Online (AJOL)

    doti

    This study investigated the effect of pH and coexisting ions on As(III) adsorption using batch experiment and discovered that pH strongly influenced As(III) adsorption. However, differences in background ionic strengths of 0.001 N NaNO3 and 0.1 N NaNO3 had no effect on the sorption trend. The isotherms followed ...

  13. MATHEMATICAL MODELING OF BATCH ADSORPTION OF MANGANESE ONTO BONE CHAR

    OpenAIRE

    Maria, M. E.; Mansur, M. B.

    2016-01-01

    Abstract The present study investigated the dynamics of batch adsorption of manganese onto bone char by using two distinct mathematical formulations: the diffusion model and the shrinking core model. Both models assumed spherical particles and adequately described the transient behavior of metal adsorption under changing operating conditions. Comparatively, the diffusion model described the manganese adsorption better at distinct particle sizes even when small particles were used (dp ≤ 0.147 ...

  14. Batch production of microchannel plate photo-multipliers

    Energy Technology Data Exchange (ETDEWEB)

    Frisch, Henry J.; Wetstein, Matthew; Elagin, Andrey

    2018-03-06

    In-situ methods for the batch fabrication of flat-panel micro-channel plate (MCP) photomultiplier tube (PMT) detectors (MCP-PMTs), without transporting either the window or the detector assembly inside a vacuum vessel are provided. The method allows for the synthesis of a reflection-mode photocathode on the entrance to the pores of a first MCP or the synthesis of a transmission-mode photocathode on the vacuum side of a photodetector entrance window.

  15. Automated handling for SAF batch furnace and chemistry analysis operations

    International Nuclear Information System (INIS)

    Bowen, W.W.; Sherrell, D.L.; Wiemers, M.J.

    1981-01-01

    The Secure Automated Fabrication Program is developing a remotely operated breeder reactor fuel pin fabrication line. The equipment will be installed in the Fuels and Materials Examination Facility being constructed at Hanford, Washington. Production is scheduled to start in mid-1986. The application of small pneumatically operated industrial robots for loading and unloading product into and out of batch furnaces and for distribution and handling of chemistry samples is described

  16. Sequencing batch-reactor control using Gaussian-process models.

    Science.gov (United States)

    Kocijan, Juš; Hvala, Nadja

    2013-06-01

    This paper presents a Gaussian-process (GP) model for the design of sequencing batch-reactor (SBR) control for wastewater treatment. The GP model is a probabilistic, nonparametric model with uncertainty predictions. In the case of SBR control, it is used for the on-line optimisation of the batch-phases duration. The control algorithm follows the course of the indirect process variables (pH, redox potential and dissolved oxygen concentration) and recognises the characteristic patterns in their time profile. The control algorithm uses GP-based regression to smooth the signals and GP-based classification for the pattern recognition. When tested on the signals from an SBR laboratory pilot plant, the control algorithm provided a satisfactory agreement between the proposed completion times and the actual termination times of the biodegradation processes. In a set of tested batches the final ammonia and nitrate concentrations were below 1 and 0.5 mg L(-1), respectively, while the aeration time was shortened considerably. Copyright © 2013 Elsevier Ltd. All rights reserved.

  17. Fault Diagnosis of Batch Reactor Using Machine Learning Methods

    Directory of Open Access Journals (Sweden)

    Sujatha Subramanian

    2014-01-01

    Full Text Available Fault diagnosis of a batch reactor gives the early detection of fault and minimizes the risk of thermal runaway. It provides superior performance and helps to improve safety and consistency. It has become more vital in this technical era. In this paper, support vector machine (SVM is used to estimate the heat release (Qr of the batch reactor both normal and faulty conditions. The signature of the residual, which is obtained from the difference between nominal and estimated faulty Qr values, characterizes the different natures of faults occurring in the batch reactor. Appropriate statistical and geometric features are extracted from the residual signature and the total numbers of features are reduced using SVM attribute selection filter and principle component analysis (PCA techniques. artificial neural network (ANN classifiers like multilayer perceptron (MLP, radial basis function (RBF, and Bayes net are used to classify the different types of faults from the reduced features. It is observed from the result of the comparative study that the proposed method for fault diagnosis with limited number of features extracted from only one estimated parameter (Qr shows that it is more efficient and fast for diagnosing the typical faults.

  18. Yields from pyrolysis of refinery residue using a batch process

    Directory of Open Access Journals (Sweden)

    S. Prithiraj

    2017-12-01

    Full Text Available Batch pyrolysis was a valuable process of assessing the potential of recovering and characterising products from hazardous waste materials. This research explored the pyrolysis of hydrocarbon-rich refinery residue, from crude oil processes, in a 1200 L electrically-heated batch retort. Furthermore, the off-gases produced were easily processed in compliance with existing regulatory emission standards. The methodology offers a novel, cost-effective and environmentally compliant method of assessing recovery potential of valuable products. The pyrolysis experiments yielded significant oil (70% with high calorific value (40 MJ/kg, char (14% with carbon content over 80% and non-condensable gas (6% with significant calorific value (240 kJ/mol. The final gas stream was subjected to an oxidative clean-up process with continuous on-line monitoring demonstrating compliance with South African emission standards. The gas treatment was overall economically optimal as only a smaller portion of the original residue was subjected to emission-controlling steps. Keywords: Batch pyrolysis, Volatiles, Oil yields, Char, Emissions, Oil recovery

  19. Analyzing data flows of WLCG jobs at batch job level

    Science.gov (United States)

    Kuehn, Eileen; Fischer, Max; Giffels, Manuel; Jung, Christopher; Petzold, Andreas

    2015-05-01

    With the introduction of federated data access to the workflows of WLCG, it is becoming increasingly important for data centers to understand specific data flows regarding storage element accesses, firewall configurations, as well as the scheduling of batch jobs themselves. As existing batch system monitoring and related system monitoring tools do not support measurements at batch job level, a new tool has been developed and put into operation at the GridKa Tier 1 center for monitoring continuous data streams and characteristics of WLCG jobs and pilots. Long term measurements and data collection are in progress. These measurements already have been proven to be useful analyzing misbehaviors and various issues. Therefore we aim for an automated, realtime approach for anomaly detection. As a requirement, prototypes for standard workflows have to be examined. Based on measurements of several months, different features of HEP jobs are evaluated regarding their effectiveness for data mining approaches to identify these common workflows. The paper will introduce the actual measurement approach and statistics as well as the general concept and first results classifying different HEP job workflows derived from the measurements at GridKa.

  20. Fed-batch production of tetanus toxin by Clostridium tetani.

    Science.gov (United States)

    Fratelli, Fernando; Siquini, Tatiana Joly; de Abreu, Marcelo Estima; Higashi, Hisako Gondo; Converti, Attilio; de Carvalho, João Carlos Monteiro

    2010-01-01

    This study deals with the effects of the initial nitrogen source (NZ Case TT) level and the protocol of glucose addition during the fed-batch production of tetanus toxin by Clostridium tetani. An increase in the initial concentration of NZ Case TT (NZ(0)) accelerated cell growth, increased the consumption of the nitrogen source as well as the final yield of tetanus toxin, which achieved the highest values (50-60 L(f)/mL) for NZ(0) > or = 50 g/L. The addition of glucose at fixed times (16, 56, and 88 h) ensured a toxin yield ( approximately 60 L(f)/mL) about 33% higher than those of fed-batch runs with addition at fixed concentration ( approximately 45 L(f)/mL) and about 300% higher than those obtained in reference batch runs nowadays used at industrial scale. The results of this work promise to substantially improve the present production of tetanus toxin and may be adopted for human vaccine production after detoxification and purification.