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Sample records for silicone encapsulation systems

  1. An accelerated stress testing program for determining the reliability sensitivity of silicon solar cells to encapsulation and metallization systems

    Science.gov (United States)

    Lathrop, J. W.; Davis, C. W.; Royal, E.

    1982-01-01

    The use of accelerated testing methods in a program to determine the reliability attributes of terrestrial silicon solar cells is discussed. Different failure modes are to be expected when cells with and without encapsulation are subjected to accelerated testing and separate test schedules for each are described. Unencapsulated test cells having slight variations in metallization are used to illustrate how accelerated testing can highlight different diffusion related failure mechanisms. The usefulness of accelerated testing when applied to encapsulated cells is illustrated by results showing that moisture related degradation may be many times worse with some forms of encapsulation than with no encapsulation at all.

  2. Design and characterization of a 3D encapsulation with silicon vias for radio frequency micro-electromechanical system resonator

    International Nuclear Information System (INIS)

    Zhao Ji-Cong; Yuan Quan; Wang Feng-Xiang; Kan Xiao; Han Guo-Wei; Yang Jin-Ling; Yang Fu-Hua; Sun Ling; Sun Hai-Yan

    2017-01-01

    In this paper, we present a three-dimensional (3D) vacuum packaging technique at a wafer level for a radio frequency micro-electromechanical system (RF MEMS) resonator, in which low-loss silicon vias is used to transmit RF signals. Au–Sn solder bonding is adopted to provide a vacuum encapsulation as well as electrical conductions. A RF model of the encapsulation cap is established to evaluate the parasitic effect of the packaging, which provides an effective design solution of 3D RF MEMS encapsulation. With the proposed packaging structure, the signal-to-background ratio (SBR) of 24 dB is achieved, as well as the quality factor ( Q -factor) of the resonator increases from 8000 to 10400 after packaging. The packaged resonator has a linear frequency–temperature ( f – T ) characteristic in a temperature range between 0 °C and 100 °C. And the package shows favorable long-term stability of the Q -factor over 200 days, which indicates that the package has excellent hermeticity. Furthermore, the average shear strength is measured to be 43.58 MPa among 10 samples. (paper)

  3. Design and characterization of a 3D encapsulation with silicon vias for radio frequency micro-electromechanical system resonator

    Science.gov (United States)

    Zhao, Ji-Cong; Yuan, Quan; Wang, Feng-Xiang; Kan, Xiao; Han, Guo-Wei; Sun, Ling; Sun, Hai-Yan; Yang, Jin-Ling; Yang, Fu-Hua

    2017-06-01

    In this paper, we present a three-dimensional (3D) vacuum packaging technique at a wafer level for a radio frequency micro-electromechanical system (RF MEMS) resonator, in which low-loss silicon vias is used to transmit RF signals. Au-Sn solder bonding is adopted to provide a vacuum encapsulation as well as electrical conductions. A RF model of the encapsulation cap is established to evaluate the parasitic effect of the packaging, which provides an effective design solution of 3D RF MEMS encapsulation. With the proposed packaging structure, the signal-to-background ratio (SBR) of 24 dB is achieved, as well as the quality factor (Q-factor) of the resonator increases from 8000 to 10400 after packaging. The packaged resonator has a linear frequency-temperature (f-T) characteristic in a temperature range between 0 °C and 100 °C. And the package shows favorable long-term stability of the Q-factor over 200 days, which indicates that the package has excellent hermeticity. Furthermore, the average shear strength is measured to be 43.58 MPa among 10 samples. Project supported by the National Natural Science Foundation of China (Grant Nos. 61234007, 61404136, and 61504130), the Fund from the Ministry of Science and Technology of China (Grant No. 2013YQ16055103), the Key Research & Development Program of Jiangsu Province, China (Grant No. BE2016007-2), and the Major Project of Natural Science Research of the Higher Education Institutions of Jiangsu Province, China (Grant No. 16KJA510006).

  4. Durable crystalline Si photovoltaic modules based on silicone-sheet encapsulants

    Science.gov (United States)

    Hara, Kohjiro; Ohwada, Hiroto; Furihata, Tomoyoshi; Masuda, Atsushi

    2018-02-01

    Crystalline Si photovoltaic (PV) modules were fabricated with sheets of poly(dimethylsiloxane) (silicone) as an encapsulant. The long-term durability of the silicone-encapsulated PV modules was experimentally investigated. The silicone-based modules enhanced the long-term durability against potential-induced degradation (PID) and a damp-heat (DH) condition at 85 °C with 85% relative humidity (RH). In addition, we designed and fabricated substrate-type Si PV modules based on the silicone encapsulant and an Al-alloy plate as the substratum, which demonstrated high impact resistance and high incombustible performance. The high chemical stability, high volume resistivity, rubber-like elasticity, and incombustibility of the silicone encapsulant resulted in the high durability of the modules. Our results indicate that silicone is an attractive encapsulation material, as it improves the long-term durability of crystalline Si PV modules.

  5. Limonene encapsulation in freeze dried gellan systems.

    Science.gov (United States)

    Evageliou, Vasiliki; Saliari, Dimitra

    2017-05-15

    The encapsulation of limonene in freeze-dried gellan systems was investigated. Surface and encapsulated limonene content was determined by measurement of the absorbance at 252nm. Gellan matrices were both gels and solutions. For a standard gellan concentration (0.5wt%) gelation was induced by potassium or calcium chloride. Furthermore, gellan solutions of varying concentrations (0.25-1wt%) were also studied. Limonene was added at two different concentrations (1 and 2mL/100g sample). Gellan gels encapsulated greater amounts of limonene than solutions. Among all gellan gels, the KCl gels had the greater encapsulated limonene content. However, when the concentration of limonene was doubled in these KCl gels, the encapsulated limonene decreased. The surface limonene content was significant, especially for gellan solutions. The experimental conditions and not the mechanical properties of the matrices were the dominant factor in the interpretation of the observed results. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Comparison of silicone and spin-on glass packaging materials for light-emitting diode encapsulation

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Liann-Be; Pan, Ke-Wei; Yen, Chia-Yi [Department of Electronic Engineering and Green Technology Research Center, Chang Gung University, Taoyuan, Taiwan (China); Jeng, Ming-Jer, E-mail: mjjeng@mail.cgu.edu.tw [Department of Electronic Engineering and Green Technology Research Center, Chang Gung University, Taoyuan, Taiwan (China); Wu, Chun-Te; Hu, Sung-Cheng; Kuo, Yang-Kuao [Chemical Systems Research Division, Chung-Shan Institute of Science and Technology Armaments Bureau, MND, Taoyuan, Taiwan (China)

    2014-11-03

    Traditional white light light-emitting diode (LED) encapsulation is performed by mixed phosphors and silicone coating on LED die. However, this encapsulation with silicone coating incurs overheated temperatures and yellowing problem. Therefore, this work attempts to replace silicone paste by using spin-on-glass (SOG) materials. Experimental results indicate that although initial brightness of SOG-based packaging is lower than that of silicone packaging, its light attenuation is significantly lower than that of silicone for a long lighting time. After the LED power is turned on for 12 h, the brightness of LED with silicone and SOG material packaging decreases from 84 to 48 lm and 73 to 59 lm, respectively. Therefore, SOG material provides an alternative packaging solution for high power LED lighting applications. - Highlights: • Spin-on-glass (SOG) material was used to replace silicone coating for LED packaging. • Initial brightness of SOG packaging is lower than that of silicone packaging. • Over time, light attenuation in SOG is much lower than that in silicone. • Color rendering index and brightness of LED packaging was optimized by Taguchi method.

  7. Thermal and optical performance of encapsulation systems for flat-plate photovoltaic modules

    Science.gov (United States)

    Minning, C. P.; Coakley, J. F.; Perrygo, C. M.; Garcia, A., III; Cuddihy, E. F.

    1981-01-01

    The electrical power output from a photovoltaic module is strongly influenced by the thermal and optical characteristics of the module encapsulation system. Described are the methodology and computer model for performing fast and accurate thermal and optical evaluations of different encapsulation systems. The computer model is used to evaluate cell temperature, solar energy transmittance through the encapsulation system, and electric power output for operation in a terrestrial environment. Extensive results are presented for both superstrate-module and substrate-module design schemes which include different types of silicon cell materials, pottants, and antireflection coatings.

  8. Silica encapsulation of luminescent silicon nanoparticles: stable and biocompatible nanohybrids

    Energy Technology Data Exchange (ETDEWEB)

    Maurice, Vincent [CEA Saclay, DSM/IRAMIS/SPAM-LFP (France); Rivolta, Ilaria [University of Milano-Bicocca, Department of Experimental Medicine (DIMS) (Italy); Vincent, Julien [CEA Saclay, DSM/IRAMIS/SPAM-LFP (France); Raccurt, Olivier [CEA Grenoble, Department of Nano Materials, NanoChemistry and NanoSafety Laboratory (DRT/LITEN/DTNM/LCSN) (France); Rouzaud, Jean-Noel [Ecole Normale superieure de Paris, Laboratoire de Geologie (France); Miserrochi, Giuseppe [University of Milano-Bicocca, Department of Experimental Medicine (DIMS) (Italy); Doris, Eric [CEA, Service de Chimie Bioorganique et de Marquage, iBiTecS (France); Reynaud, Cecile; Herlin-Boime, Nathalie, E-mail: nathalie.herlin@cea.fr [CEA Saclay, DSM/IRAMIS/SPAM-LFP (France)

    2012-02-15

    This article presents a process for surface coating and functionalization of luminescent silicon nanoparticles. The particles were coated with silica using a microemulsion process that was adapted to the fragile silicon nanoparticles. The as-produced core-shell particles have a mean diameter of 35 nm and exhibit the intrinsic photoluminescence of the silicon core. The silica layer protects the core from aqueous oxidation for several days, thus allowing the use of the nanoparticles for biological applications. The nanoparticles were further coated with amines and functionalized with polyethylene glycol chains and the toxicity of the particles has been evaluated at the different stages of the process. The core-shell nanoparticles exhibit no acute toxicity towards lung cells, which is promising for further development.

  9. Silicon-Polymer Encapsulation of High-Level Calcine Waste for Transportation or Disposal

    International Nuclear Information System (INIS)

    Loomis, G.G.; Miller, C.M.; Giansiracusa, J.A.; Kimmel, R.; Prewett, S.V.

    2000-01-01

    This report presents the results of an experimental study investigating the potential uses for silicon-polymer encapsulation of High Level Calcine Waste currently stored within the Idaho Nuclear Technology and Engineering Center (INTEC) at the Idaho National Engineering and Environmental Laboratory (INEEL). The study investigated two different applications of silicon polymer encapsulation. One application uses silicon polymer to produce a waste form suitable for disposal at a High Level Radioactive Waste Disposal Facility directly, and the other application encapsulates the calcine material for transportation to an offsite melter for further processing. A simulated waste material from INTEC, called pilot scale calcine, which contained hazardous materials but no radioactive isotopes was used for the study, which was performed at the University of Akron under special arrangement with Orbit Technologies, the originators of the silicon polymer process called Polymer Encapsulation Technology (PET). This document first discusses the PET process, followed by a presentation of past studies involving PET applications to waste problems. Next, the results of an experimental study are presented on encapsulation of the INTEC calcine waste as it applies to transportation or disposal of calcine waste. Results relating to long-term disposal include: (1) a characterization of the pilot calcine waste; (2) Toxicity Characteristic Leaching Procedure (TCLP) testing of an optimum mixture of pilot calcine, polysiloxane and special additives; and, (3) Material Characterization Center testing MCC-1P evaluation of the optimum waste form. Results relating to transportation of the calcine material for a mixture of maximum waste loading include: compressive strength testing, 10-m drop test, melt testing, and a Department of Transportation (DOT) oxidizer test

  10. Influence of epoxy resin as encapsulation material of silicon photovoltaic cells on maximum current

    Directory of Open Access Journals (Sweden)

    Acevedo-Gómez David

    2017-01-01

    Full Text Available This work presents an analysis about how the performance of silicon photovoltaic cells is influenced by the use of epoxy resin as encapsulation material with flat roughness. The effect of encapsulation on current at maximum power of mono-crystalline cell was tested indoor in a solar simulator bench at 1000 w/m² and AM1.5G. The results show that implementation of flat roughness layer onto cell surface reduces the maximum current inducing on average 2.7% less power with respect to a cell before any encapsulation. The losses of power and, in consequence, the less production of energy are explained by resin light absorption, reflection and partially neutralization of non-reflective coating.

  11. Spectral perturbations from silicon diode detector encapsulation and shielding in photon fields.

    Science.gov (United States)

    Eklund, Karin; Ahnesjö, Anders

    2010-11-01

    Silicon diodes are widely used as detectors for relative dose measurements in radiotherapy. The common manufacturing practice is to encapsulate the diodes in plastic for protection and to facilitate mounting in scanning devices. Diodes intended for use in photon fields commonly also have a shield of a high atomic number material (usually tungsten) integrated into the encapsulation to selectively absorb low-energy photons to which silicon diodes would otherwise over-response. However, new response models based on cavity theories and spectra calculations have been proposed for direct correction of the readout from unshielded (e.g., "electron") diodes used in photon fields. This raises the question whether it is correct to assume that the spectrum in a water phantom at the location of the detector cavity is not perturbed by the detector encapsulation materials. The aim of this work is to investigate the spectral effects of typical encapsulations, including shielding, used for clinical diodes. The effects of detector encapsulation of an unshielded and a shielded commercial diode on the spectra at the detector cavity location are studied through Monte Carlo simulations with PENELOPE-2005. Variance reduction based on correlated sampling is applied to reduce the CPU time needed for the simulations. The use of correlated sampling is found to be efficient and to not introduce any significant bias to the results. Compared to reference spectra calculated in water, the encapsulation for an unshielded diode is demonstrated to not perturb the spectrum, while a tungsten shielded diode caused not only the desired decrease in low-energy scattered photons but also a large increase of the primary electron fluence. Measurements with a shielded diode in a 6 MV photon beam proved that the shielding does not completely remove the field-size dependence of the detector response caused by the over-response from low-energy photons. Response factors of a properly corrected unshielded diode

  12. Silicon nanopore membrane (SNM) for islet encapsulation and immunoisolation under convective transport

    Science.gov (United States)

    Song, Shang; Faleo, Gaetano; Yeung, Raymond; Kant, Rishi; Posselt, Andrew M.; Desai, Tejal A.; Tang, Qizhi; Roy, Shuvo

    2016-03-01

    Problems associated with islet transplantation for Type 1 Diabetes (T1D) such as shortage of donor cells, use of immunosuppressive drugs remain as major challenges. Immune isolation using encapsulation may circumvent the use of immunosuppressants and prolong the longevity of transplanted islets. The encapsulating membrane must block the passage of host’s immune components while providing sufficient exchange of glucose, insulin and other small molecules. We report the development and characterization of a new generation of semipermeable ultrafiltration membrane, the silicon nanopore membrane (SNM), designed with approximately 7 nm-wide slit-pores to provide middle molecule selectivity by limiting passage of pro-inflammatory cytokines. Moreover, the use of convective transport with a pressure differential across the SNM overcomes the mass transfer limitations associated with diffusion through nanometer-scale pores. The SNM exhibited a hydraulic permeability of 130 ml/hr/m2/mmHg, which is more than 3 fold greater than existing polymer membranes. Analysis of sieving coefficients revealed 80% reduction in cytokines passage through SNM under convective transport. SNM protected encapsulated islets from infiltrating cytokines and retained islet viability over 6 hours and remained responsive to changes in glucose levels unlike non-encapsulated controls. Together, these data demonstrate the novel membrane exhibiting unprecedented hydraulic permeability and immune-protection for islet transplantation therapy.

  13. Ultra-thin film encapsulation processes for micro-electro-mechanical devices and systems

    International Nuclear Information System (INIS)

    Stoldt, Conrad R; Bright, Victor M

    2006-01-01

    A range of physical properties can be achieved in micro-electro-mechanical systems (MEMS) through their encapsulation with solid-state, ultra-thin coatings. This paper reviews the application of single source chemical vapour deposition and atomic layer deposition (ALD) in the growth of submicron films on polycrystalline silicon microstructures for the improvement of microscale reliability and performance. In particular, microstructure encapsulation with silicon carbide, tungsten, alumina and alumina-zinc oxide alloy ultra-thin films is highlighted, and the mechanical, electrical, tribological and chemical impact of these overlayers is detailed. The potential use of solid-state, ultra-thin coatings in commercial microsystems is explored using radio frequency MEMS as a case study for the ALD alloy alumina-zinc oxide thin film. (topical review)

  14. A quantitative method for photovoltaic encapsulation system optimization

    Science.gov (United States)

    Garcia, A., III; Minning, C. P.; Cuddihy, E. F.

    1981-01-01

    It is pointed out that the design of encapsulation systems for flat plate photovoltaic modules requires the fulfillment of conflicting design requirements. An investigation was conducted with the objective to find an approach which will make it possible to determine a system with optimum characteristics. The results of the thermal, optical, structural, and electrical isolation analyses performed in the investigation indicate the major factors in the design of terrestrial photovoltaic modules. For defect-free materials, minimum encapsulation thicknesses are determined primarily by structural considerations. Cell temperature is not strongly affected by encapsulant thickness or thermal conductivity. The emissivity of module surfaces exerts a significant influence on cell temperature. Encapsulants should be elastomeric, and ribs are required on substrate modules. Aluminum is unsuitable as a substrate material. Antireflection coating is required on cell surfaces.

  15. Encapsulating of high-level radioactive waste with use of pyrocarbon and silicon carbide coatings

    International Nuclear Information System (INIS)

    Chernikov, A.

    2007-01-01

    It is known that high-level radioactive waste (HLW) constitute a real danger to biosphere, especially that their part, which contains transuranium and long-lived radionuclides resulting during reprocessing of nuclear fuel industrial and power reactors. Such waste contains approximately 99 % of long-lived fission products and transplutonium elements. At present, the concept of multi barrier protection of biosphere from radioactive waste is generally acknowledged. The main barriers are the physicochemical form of waste and enclosing strata of geological formation at places of waste-disposal. Applied methods of solidification of HLW with preparation of phosphatic and borosilicate glasses do not guarantee in full measure safety of places of waste-disposal of solidified waste in geological formations during thousand years. One promising way to improve HLW handling safety is placing of radionuclides in mineral-like matrixes similar to natural materials. The other possible way to increase safety of HLW disposal places is suggested for research by experts of Russian research institutes, for example, in the proposal for the Project of ISTC and considered in the present report, is to introduce an additional barrier on a radionuclides migration path by coating of HLW particles. Unique protective properties of pyrocarbon and silicon carbide such as low coefficients of diffusion of gaseous and solid fission products and high chemical and radiation stability [1] attract attention to these materials for coating of solidified HLW. The objective of the Project is the development of method of HLW encapsulating with use of pyrocarbon and silicon carbide coatings. To gain this end main direction of researches, including analysis of various encapsulation processes of fractionated HLW, and expected results are presented. Realization of the Project will allow to prove experimentally the efficiency of the proposed approach in the solution of the problem of HLW conditioning and ecological

  16. Methods for characterization of wafer-level encapsulation applied on silicon to LTCC anodic bonding

    International Nuclear Information System (INIS)

    Khan, M F; Ghavanini, F A; Enoksson, P; Haasl, S; Löfgren, L; Persson, K; Rusu, C; Schjølberg-Henriksen, K

    2010-01-01

    This paper presents initial results on generic characterization methods for wafer-level encapsulation. The methods, developed specifically to evaluate anodic bonding of low-temperature cofired ceramics (LTCC) to Si, are generally applicable to wafer-level encapsulation. Different microelectromechanical system (MEMS) structures positioned over the whole wafer provide local information about the bond quality. The structures include (i) resonating cantilevers as pressure sensors for bond hermeticity, (ii) resonating bridges as stress sensors for measuring the stress induced by the bonding and (iii) frames/mesas for pull tests. These MEMS structures have been designed, fabricated and characterized indicating that local information can easily be obtained. Buried electrodes to enable localized bonding have been implemented and their effectiveness is indicated from first results of the novel Si to LTCC anodic bonding.

  17. Encapsulation and delivery of food ingredients using starch based systems.

    Science.gov (United States)

    Zhu, Fan

    2017-08-15

    Functional ingredients can be encapsulated by various wall materials for controlled release in food and digestion systems. Starch, as one of the most abundant natural carbohydrate polymers, is non-allergenic, GRAS, and cheap. There has been increasing interest of using starch in native and modified forms to encapsulate food ingredients such as flavours, lipids, polyphenols, carotenoids, vitamins, enzymes, and probiotics. Starches from various botanical sources in granular or amorphous forms are modified by chemical, physical, and/or enzymatic means to obtain the desired properties for targeted encapsulation. Other wall materials are also employed in combination with starch to facilitate some types of encapsulation. Various methods of crafting the starch-based encapsulation such as electrospinning, spray drying, antisolvent, amylose inclusion complexation, and nano-emulsification are introduced in this mini-review. The physicochemical and structural properties of the particles are described. The encapsulation systems can positively influence the controlled release of food ingredients in food and nutritional applications. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Loose-fit graphitic encapsulation of silicon nanowire for one-dimensional Si anode design

    Institute of Scientific and Technical Information of China (English)

    Seh-Yoon Lim; Sudong Chae; Su-Ho Jung; Yuhwan Hyeon; Wonseok Jang; Won-Sub Yoon; Jae-Young Choi; Dongmok Whang

    2017-01-01

    Silicon nanowires (SiNWs) encapsulated with graphene-like carbon sheath (GS) having a void space in between (SiNW@V@GS) are demonstrated for the improved electrochemical performance of Si anode in lithium ion battery.The SiNW@V@GS structure was synthesized by a scalable fabrication method including four successive reactions:metal-catalyzed CVD growth of SiNWs,controlled thermal oxidation,and deposition of the graphitic layer,to form SiNW@SiO2@GS and additional chemical etching of sacrificial SiO2 layer between SiNWs and carbon sheath.During the synthetic process,the thickness of the void spacing was controlled by adjusting the oxidation-dependent process.The well-controlled void space and crystalline graphitic carbon sheath of the SiNW@V@GS structure enable good reversible capacity of 1444 mAhg-1 and cycling stability of 85% over 150 cycles.

  19. Silicon-Encapsulated Hollow Carbon Nanofiber Networks as Binder-Free Anodes for Lithium Ion Battery

    Directory of Open Access Journals (Sweden)

    Ding Nan

    2014-01-01

    Full Text Available Silicon-encapsulated hollow carbon nanofiber networks with ample space around the Si nanoparticles (hollow Si/C composites were successfully synthesized by dip-coating phenolic resin onto the surface of electrospun Si/PVA nanofibers along with the subsequent solidification and carbonization. More importantly, the structure and Si content of hollow Si/C composite nanofibers can be effectively tuned by merely varying the concentration of dip solution. As-synthesized hollow Si/C composites show excellent electrochemical performance when they are used as binder-free anodes for Li-ion batteries (LIBs. In particular, when the concentration of resol/ethanol solution is 3.0%, the product exhibits a large capacity of 841 mAh g−1 in the first cycle, prominent cycling stability, and good rate capability. The discharge capacity retention of it was ~90%, with 745 mAh g−1 after 50 cycles. The results demonstrate that the hollow Si/C composites are very promising as alternative anode candidates for high-performance LIBs.

  20. Dissolution of Monocrystalline Silicon Nanomembranes and Their Use as Encapsulation Layers and Electrical Interfaces in Water-Soluble Electronics.

    Science.gov (United States)

    Lee, Yoon Kyeung; Yu, Ki Jun; Song, Enming; Barati Farimani, Amir; Vitale, Flavia; Xie, Zhaoqian; Yoon, Younghee; Kim, Yerim; Richardson, Andrew; Luan, Haiwen; Wu, Yixin; Xie, Xu; Lucas, Timothy H; Crawford, Kaitlyn; Mei, Yongfeng; Feng, Xue; Huang, Yonggang; Litt, Brian; Aluru, Narayana R; Yin, Lan; Rogers, John A

    2017-12-26

    The chemistry that governs the dissolution of device-grade, monocrystalline silicon nanomembranes into benign end products by hydrolysis serves as the foundation for fully eco/biodegradable classes of high-performance electronics. This paper examines these processes in aqueous solutions with chemical compositions relevant to groundwater and biofluids. The results show that the presence of Si(OH) 4 and proteins in these solutions can slow the rates of dissolution and that ion-specific effects associated with Ca 2+ can significantly increase these rates. This information allows for effective use of silicon nanomembranes not only as active layers in eco/biodegradable electronics but also as water barriers capable of providing perfect encapsulation until their disappearance by dissolution. The time scales for this encapsulation can be controlled by introduction of dopants into the Si and by addition of oxide layers on the exposed surfaces.The former possibility also allows the doped silicon to serve as an electrical interface for measuring biopotentials, as demonstrated in fully bioresorbable platforms for in vivo neural recordings. This collection of findings is important for further engineering development of water-soluble classes of silicon electronics.

  1. Process and system to encapsulate spent nuclear fuel

    International Nuclear Information System (INIS)

    Gunasekaran, Muthian; Fleischer, L.R.

    1980-01-01

    System for encapsulating spent nuclear fuel containing active fission matter and comprised in a metal casing, where concrete covers this casing in a contiguous, uniform and complete manner. It is characterized in that this concrete contains metal fibres to raise the thermal conductivity and polymers for increasing impermeability and that convection facilities are provided for cooling the outer surface of the concrete [fr

  2. Polyaniline-encapsulated silicon on three-dimensional carbon nanotubes foam with enhanced electrochemical performance for lithium-ion batteries

    Science.gov (United States)

    Zhou, Xiaoming; Liu, Yang; Du, Chunyu; Ren, Yang; Mu, Tiansheng; Zuo, Pengjian; Yin, Geping; Ma, Yulin; Cheng, Xinqun; Gao, Yunzhi

    2018-03-01

    Seeking free volume around nanostructures for silicon-based anodes has been a crucial strategy to improve cycling and rate performance in the next generation Li-ion batteries. Herein, through a simple pyrolysis and in-situ polymerization approach, the low cost commercially available melamine foam as a soft template converts carbon nanotubes into highly dispersed and three-dimensionally interconnected framework with encapsulated silicon/polyaniline hierarchical nanoarchitecture. This unique core-sheath structure based on carbon nanotubes foam integrates a large number of mesoporous, thus providing well-accessible space for electrolyte wetting, whereas the carbon nanotubes matrix serves as conductive thoroughfares for electron transport. Meanwhile, the outer polyaniline coated on silicon nanoparticles provides effective space for volume expansion of silicon, further inhibiting the active material escape from the current collector. As expected, the PANI-Si@CNTs foam exhibits a high initial specific capacity of 1954 mAh g-1 and retains 727 mAh g-1 after 100 cycles at 100 mA g-1, which can be attributed to highly electrical conductivity of carbon nanotubes and protective layer of polyaniline sheath, together with three-dimensionally interconnected porous skeleton. This facile structure can pave a way for large scale synthesis of high durable silicon-based anodes or other electrode materials with huge volume expansion.

  3. Novel encapsulation technique for incorporation of high permittivity fillers into silicone elastomers

    DEFF Research Database (Denmark)

    Mazurek, Piotr Stanislaw; Hvilsted, Søren; Skov, Anne Ladegaard

    2014-01-01

    permittivity fillers, 2) Grafting of high permittivity molecules onto the polymer backbone in the elastomer, and 3) Encapsulation of high permittivity fillers. The approach investigated here is a new type of encapsulation which does not interfere with the mechanical properties to the same content...

  4. Performance of hybrid photon detector prototypes with encapsulated silicon pixel detector and readout for the RICH counters of LHCb

    International Nuclear Information System (INIS)

    Campbell, M.; George, K.A.; Girone, M.; Gys, T.; Jolly, S.; Piedigrossi, D.; Riedler, P.; Rozema, P.; Snoeys, W.; Wyllie, K.

    2003-01-01

    These proceedings report on the performance of the latest prototype pixel hybrid photon detector in preparation for the LHCb Ring Imaging Cherenkov detectors. The prototype encapsulates a silicon pixel detector bump-bonded to a binary read-out chip with short (25 ns) peaking time and low ( - ) detection threshold. A brief description of the prototype is given, followed by the preliminary results of the characterisation of the prototype behaviour when tested using a low intensity pulsed light emitting diode. The results obtained are in good agreement with those obtained using previous prototypes. The proceedings conclude with a summary of the current status and future plans

  5. Elastic silicone encapsulation of n-hexadecyl bromide by microfluidic approach as novel microencapsulated phase change materials

    Energy Technology Data Exchange (ETDEWEB)

    Fu, Zhenjin [Research Center of Laser Fusion, China Academy of Engineering Physics, Mianyang 621900 (China); School of Materials Science and Engineering, Southwest University of Science and Technology, Mianyang 621010 (China); Su, Lin; Li, Jing; Yang, Ruizhuang; Zhang, Zhanwen; Liu, Meifang; Li, Jie [Research Center of Laser Fusion, China Academy of Engineering Physics, Mianyang 621900 (China); Li, Bo, E-mail: LB6711@126.com [Research Center of Laser Fusion, China Academy of Engineering Physics, Mianyang 621900 (China)

    2014-08-20

    Highlights: • n-Hexadecyl bromide was encapsuled in elastic silicone shell. • The surfaces of microcapsules were smooth and the cross sections were compact. • Latent heat of microcapsules was 76.35 J g{sup −1}. • The microencapsulation ratio was 49 wt.%. • The microcapsules had good thermal stability. - Abstract: The elastic silicone/n-hexadecyl bromide microcapsules were prepared as novel microencapsulated phase change materials by microfluidic approach with the co-flowing channels, where the double oil1-in-oil2-in-water (O1/O2/W) droplets with a core–shell geometry were fabricated. The thermal characterizations of the microcapsules were investigated using differential scanning calorimetry (DSC) and thermogravimetry analysis (TGA). The DSC results showed that the microcapsules had good energy storage capacity with melting and freezing enthalpies 76.35 J g{sup −1} and 78.67 J g{sup −1}, respectively. The TGA investigation showed that the microcapsules had good thermal stability. The surfaces of microcapsules were smooth and the cross sections were compact from the results of optical microscope and scanning electron microscopy (SEM). Optical microscope showed that the silicone shell can provide expansion place due to its elastic property. Therefore, the silicone/n-hexadecyl bromide microcapsules showed good potential as thermal regulating textile and thermal insulation materials.

  6. Elastic silicone encapsulation of n-hexadecyl bromide by microfluidic approach as novel microencapsulated phase change materials

    International Nuclear Information System (INIS)

    Fu, Zhenjin; Su, Lin; Li, Jing; Yang, Ruizhuang; Zhang, Zhanwen; Liu, Meifang; Li, Jie; Li, Bo

    2014-01-01

    Highlights: • n-Hexadecyl bromide was encapsuled in elastic silicone shell. • The surfaces of microcapsules were smooth and the cross sections were compact. • Latent heat of microcapsules was 76.35 J g −1 . • The microencapsulation ratio was 49 wt.%. • The microcapsules had good thermal stability. - Abstract: The elastic silicone/n-hexadecyl bromide microcapsules were prepared as novel microencapsulated phase change materials by microfluidic approach with the co-flowing channels, where the double oil1-in-oil2-in-water (O1/O2/W) droplets with a core–shell geometry were fabricated. The thermal characterizations of the microcapsules were investigated using differential scanning calorimetry (DSC) and thermogravimetry analysis (TGA). The DSC results showed that the microcapsules had good energy storage capacity with melting and freezing enthalpies 76.35 J g −1 and 78.67 J g −1 , respectively. The TGA investigation showed that the microcapsules had good thermal stability. The surfaces of microcapsules were smooth and the cross sections were compact from the results of optical microscope and scanning electron microscopy (SEM). Optical microscope showed that the silicone shell can provide expansion place due to its elastic property. Therefore, the silicone/n-hexadecyl bromide microcapsules showed good potential as thermal regulating textile and thermal insulation materials

  7. Electrochemical characteristics of porous TiO2 encapsulated silicon anode

    International Nuclear Information System (INIS)

    Jeon, Bup Ju; Lee, Joong Kee

    2011-01-01

    Graphical abstract: Cycling performances of the TiO 2 coated silicon anode at different catalyst pH values. Display Omitted Highlights: → TiO 2 coated silicon was used as the anode material for lithium batteries. → TiO 2 layer acted as a buffer layer for reducing the volume expansion. → Pore size distribution of TiO 2 coated silicon influenced discharge capacity. → Higher capacity retention was exhibited at pH 10.7. - Abstract: TiO 2 coated silicon, which was prepared by the modified sol-gel method, was employed as the anode material for lithium secondary batteries and the relationship between the diffusivity and electrochemical characteristics was investigated. The results showed that the physical properties of the samples, such as their diffusivity and pore size distribution, enhanced the cycling efficiency of the TiO 2 coated silicon, probably due to the reduction of the side reactions, which may be closely related to the pore size distribution of the TiO 2 coating layer. The pore size of the coating layer plays an important role in retarding the lithium ion diffusion. In the experimental range studied herein, higher capacity retention was exhibited for the TiO 2 coated silicon prepared at pH 10.7.

  8. The Solenoidal Detector Collaboration silicon detector system

    International Nuclear Information System (INIS)

    Ziock, H.J.; Gamble, M.T.; Miller, W.O.; Palounek, A.P.T.; Thompson, T.C.

    1992-01-01

    Silicon tracking systems will be fundamental components of the tracking systems for both planned major SSC experiments. Despite its seemingly small size, it occupies a volume of more than 5 meters in length and 1 meter in diameter and is an order of magnitude larger than any silicon detector system previously built. This report discusses its design and operation

  9. Accelerated/abbreviated test methods of the low-cost silicon solar array project. Study 4, task 3: Encapsulation

    Science.gov (United States)

    Kolyer, J. M.; Mann, N. R.

    1977-01-01

    Methods of accelerated and abbreviated testing were developed and applied to solar cell encapsulants. These encapsulants must provide protection for as long as 20 years outdoors at different locations within the United States. Consequently, encapsulants were exposed for increasing periods of time to the inherent climatic variables of temperature, humidity, and solar flux. Property changes in the encapsulants were observed. The goal was to predict long term behavior of encapsulants based upon experimental data obtained over relatively short test periods.

  10. A continuous Czochralski silicon crystal growth system

    Science.gov (United States)

    Wang, C.; Zhang, H.; Wang, T. H.; Ciszek, T. F.

    2003-03-01

    Demand for large silicon wafers has driven the growth of silicon crystals from 200 to 300 mm in diameter. With the increasing silicon ingot sizes, melt volume has grown dramatically. Melt flow becomes more turbulent as melt height and volume increase. To suppress turbulent flow in a large silicon melt, a new Czochralski (CZ) growth furnace has been designed that has a shallow melt. In this new design, a crucible consists of a shallow growth compartment in the center and a deep feeding compartment around the periphery. Two compartments are connected with a narrow annular channel. A long crystal may be continuously grown by feeding silicon pellets into the dedicated feeding compartment. We use our numerical model to simulate temperature distribution and velocity field in a conventional 200-mm CZ crystal growth system and also in the new shallow crucible CZ system. By comparison, advantages and disadvantages of the proposed system are observed, operating conditions are determined, and the new system is improved.

  11. Novel encapsulation systems and processes for overcoming the challenges of polypharmacy.

    Science.gov (United States)

    Orlu-Gul, Mine; Topcu, Ahmet Alptekin; Shams, Talayeh; Mahalingam, Suntharavathanan; Edirisinghe, Mohan

    2014-10-01

    The encapsulation process has been studied to develop smart drug delivery systems for decades. In particular, micro-encapsulation and nano-encapsulation approaches have gained wide interest in the development of particulate drug delivery and achieved progress in specialties such as nano-medicine. Encapsulation technologies have evolved through various platforms including emulsion solvent evaporation, spray drying and polymer conjugation. Among current encapsulation methods, electrohydrodynamic and microfluidic processes stand out by enabling the making of formulations with uniform shape and nanoscale size. Pressurized gyration is a new method of combining rotation and controlled pressure to produce encapsulated structures of various morphologies. In this review we address key developments in electrohydrodynamic, microfluidic, their combined and new approaches as well as their potential to obtain combined therapies with desired drug release profiles. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. Efficient and Stable CsPbBr3 Quantum-Dot Powders Passivated and Encapsulated with a Mixed Silicon Nitride and Silicon Oxide Inorganic Polymer Matrix.

    Science.gov (United States)

    Yoon, Hee Chang; Lee, Soyoung; Song, Jae Kyu; Yang, Heesun; Do, Young Rag

    2018-04-11

    Despite the excellent optical features of fully inorganic cesium lead halide (CsPbX 3 ) perovskite quantum dots (PeQDs), their unstable nature has limited their use in various optoelectronic devices. To mitigate the instability issues of PeQDs, we demonstrate the roles of dual-silicon nitride and silicon oxide ligands of the polysilazane (PSZ) inorganic polymer to passivate the surface defects and form a barrier layer coated onto green CsPbBr 3 QDs to maintain the high photoluminescence quantum yield (PLQY) and improve the environmental stability. The mixed SiN x /SiN x O y /SiO y passivated and encapsulated CsPbBr 3 /PSZ core/shell composite can be prepared by a simple hydrolysis reaction involving the addition of adding PSZ as a precursor and a slight amount of water into a colloidal CsPbBr 3 QD solution. The degree of the moisture-induced hydrolysis reaction of PSZ can affect the compositional ratio of SiN x , SiN x O y , and SiO y liganded to the surfaces of the CsPbBr 3 QDs to optimize the PLQY and the stability of CsPbBr 3 /PSZ core/shell composite, which shows a high PLQY (∼81.7%) with improved thermal, photo, air, and humidity stability as well under coarse conditions where the performance of CsPbBr 3 QDs typically deteriorate. To evaluate the suitability of the application of the CsPbBr 3 /PSZ powder to down-converted white-light-emitting diodes (DC-WLEDs) as the backlight of a liquid crystal display (LCD), we fabricated an on-package type of tricolor-WLED by mixing the as-synthesized green CsPbBr 3 /PSZ composite powder with red K 2 SiF 6 :Mn 4+ phosphor powder and a poly(methyl methacrylate)-encapsulating binder and coating this mixed paste onto a cup-type blue LED. The fabricated WLED show high luminous efficacy of 138.6 lm/W (EQE = 51.4%) and a wide color gamut of 128% and 111% without and with color filters, respectively, at a correlated color temperature of 6762 K.

  13. Fabrication of a multifunctional nano-in-micro drug delivery platform by microfluidic templated encapsulation of porous silicon in polymer matrix.

    Science.gov (United States)

    Zhang, Hongbo; Liu, Dongfei; Shahbazi, Mohammad-Ali; Mäkilä, Ermei; Herranz-Blanco, Bárbara; Salonen, Jarno; Hirvonen, Jouni; Santos, Hélder A

    2014-07-09

    A multifunctional nano-in-micro drug delivery platform is developed by conjugating the porous silicon nanoparticles with mucoadhesive polymers and subsequent encapsulation into a pH-responsive polymer using microfluidics. The multistage platform shows monodisperse size distribution and pH-responsive payload release, and the released nanoparticles are mucoadhesive. Moreover, this platform is capable of simultaneously loading and releasing multidrugs with distinct properties. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Design, analysis, and test verification of advanced encapsulation systems

    Science.gov (United States)

    Garcia, A.; Minning, C.

    1981-01-01

    Thermal, optical, structural, and electrical isolation analyses are decribed. Major factors in the design of terrestrial photovoltaic modules are discussed. Mechanical defects in the different layers of an encapsulation system, it was found, would strongly influence the minimum pottant thickness required for electrical isolation. Structural, optical, and electrical properties, a literature survey indicated, are hevily influenced by the presence of moisture. These items, identified as technology voids, are discussed. Analyses were based upon a 1.2 meter square module using 10.2 cm (4-inch) square cells placed 1.3 mm apart as shown in Figure 2-2. Sizing of the structural support member of a module was determined for a uniform, normal pressure load of 50 psf, corresponding to the pressure difference generated between the front and back surface of a module by a 100 mph wind. Thermal and optical calculations were performed for a wind velocity of 1 meter/sec parallel to the ground and for module tilt (relative to the local horizontal) of 37 deg. Placement of a module in a typical array field is illustrated.

  15. Thyme Oil Encapsulated in Halloysite Nanotubes for Antimicrobial Packaging System.

    Science.gov (United States)

    Lee, Min Hyeock; Seo, Hyun-Sun; Park, Hyun Jin

    2017-04-01

    An antimicrobial capsule releasing thyme oil was developed using modified halloysite nanotubes (HNTs). In order to increase the pore volume, HNTs were treated with 5.0 mol/L NaOH solution, which resulted in the encapsulation of more thyme oil molecules inside the HNTs. The morphology of the raw HNTs and NaOH-treated HNTs (N-HNTs) was characterized using transmission electron microscopy and nitrogen adsorption-desorption analysis. The loading capacity increased from 180.7 ± 12.7 to 256.4 ± 16.7 mg thyme oil/g HNT after the NaOH treatment. The aerial release characteristics of thyme oil from both the HNT capsules were investigated in a closed-package atmosphere system at 4, 25, and 40 °C. The antimicrobial activity of the capsule against Escherichia coli O157:H7 was determined using the vapor phase assay. Moreover, the antimicrobial effects of the capsule against E. coli O157:H7, total mesophilic aerobic bacteria (MAB), and molds and yeasts (MY) on the surfaces of cherry tomatoes were investigated at 4 and 25 °C for 5 d. When the cherry tomatoes were exposed to the thyme oil-loaded N-HNT capsule, the number of E. coli O157:H7, MAB, and MY significantly reduced during storage. © 2017 Institute of Food Technologists®.

  16. Design, analysis, and test verification of advanced encapsulation systems

    Science.gov (United States)

    Garcia, A.; Minning, C.

    1981-11-01

    Thermal, optical, structural, and electrical isolation analyses are decribed. Major factors in the design of terrestrial photovoltaic modules are discussed. Mechanical defects in the different layers of an encapsulation system, it was found, would strongly influence the minimum pottant thickness required for electrical isolation. Structural, optical, and electrical properties, a literature survey indicated, are hevily influenced by the presence of moisture. These items, identified as technology voids, are discussed. Analyses were based upon a 1.2 meter square module using 10.2 cm (4-inch) square cells placed 1.3 mm apart as shown in Figure 2-2. Sizing of the structural support member of a module was determined for a uniform, normal pressure load of 50 psf, corresponding to the pressure difference generated between the front and back surface of a module by a 100 mph wind. Thermal and optical calculations were performed for a wind velocity of 1 meter/sec parallel to the ground and for module tilt (relative to the local horizontal) of 37 deg. Placement of a module in a typical array field is illustrated.

  17. Silicon photonics III systems and applications

    CERN Document Server

    Lockwood, David

    2016-01-01

    This book is volume III of a series of books on silicon photonics. It reports on the development of fully integrated systems where many different photonics component are integrated together to build complex circuits. This is the demonstration of the fully potentiality of silicon photonics. It contains a number of chapters written by engineers and scientists of the main companies, research centers and universities active in the field. It can be of use for all those persons interested to know the potentialities and the recent applications of silicon photonics both in microelectronics, telecommunication and consumer electronics market.

  18. Methods and systems using encapsulated tracers and chemicals for reservoir interrogation and manipulation

    Science.gov (United States)

    Roberts, Jeffery; Aines, Roger D; Duoss, Eric B; Spadaccini, Christopher M

    2014-11-04

    An apparatus, method, and system of reservoir interrogation. A tracer is encapsulating in a receptacle. The receptacle containing the tracer is injected into the reservoir. The tracer is analyzed for reservoir interrogation.

  19. Robust Wafer-Level Thin-Film Encapsulation (Packaging) of Microstructures (MEMS) using Low Stress PECVD Silicon Carbide

    NARCIS (Netherlands)

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

    2009-01-01

    This paper presents a new low-cost, CMOS-compatible and robust wafer-level encapsulation technique developed using a stress-optimised PECVD SiC as the capping and sealing material, imparting harsh environment capability. This technique has been applied for the fabrication and encapsulation of a wide

  20. Photovoltaic module encapsulation design and materials selection, volume 1

    Science.gov (United States)

    Cuddihy, E.; Carroll, W.; Coulbert, C.; Gupta, A.; Liang, R. H.

    1982-01-01

    Encapsulation material system requirements, material selection criteria, and the status and properties of encapsulation materials and processes available are presented. Technical and economic goals established for photovoltaic modules and encapsulation systems and their status are described. Available encapsulation technology and data are presented to facilitate design and material selection for silicon flat plate photovoltaic modules, using the best materials available and processes optimized for specific power applications and geographic sites. The operational and environmental loads that encapsulation system functional requirements and candidate design concepts and materials that are identified to have the best potential to meet the cost and performance goals for the flat plate solar array project are described. Available data on encapsulant material properties, fabrication processing, and module life and durability characteristics are presented.

  1. Note: Automated optical focusing on encapsulated devices for scanning light stimulation systems

    International Nuclear Information System (INIS)

    Bitzer, L. A.; Benson, N.; Schmechel, R.

    2014-01-01

    Recently, a scanning light stimulation system with an automated, adaptive focus correction during the measurement was introduced. Here, its application on encapsulated devices is discussed. This includes the changes an encapsulating optical medium introduces to the focusing process as well as to the subsequent light stimulation measurement. Further, the focusing method is modified to compensate for the influence of refraction and to maintain a minimum beam diameter on the sample surface

  2. The ternary system nickel-boron-silicon

    International Nuclear Information System (INIS)

    Lugscheider, E.; Reimann, H.; Knotek, O.

    1975-01-01

    The ternary system Nickel-Boron-Silicon was established at 850 0 C by means of X-ray diffraction, metallographic and micro-hardness examinations. The well known binary nickel borides and silicides resp. were confirmed. In the boron-silicon system two binary phases, SiBsub(4-x) with x approximately 0.7 and SiB 6 were found the latter in equilibrium with the β-rhombohedral boron. Confirming the two ternary silicon borides a greater homogeneity range was found for Ni 6 Si 2 B, the phase Nisub(4,6)Si 2 B published by Uraz and Rundqvist can better be described by the formula Nisub(4.29)Si 2 Bsub(1.43). In relation to further investigations we measured melting temperatures in ternary Ni-10 B-Si alloys by differential thermoanalysis. (author)

  3. The solenoidal detector collaboration silicon detector system

    International Nuclear Information System (INIS)

    Ziock, H.J.; Gamble, M.T.; Miller, W.O.; Palounek, A.P.T.; Thompson, T.C.

    1992-01-01

    Silicon tracking systems (STS) will be fundamental components of the tracking systems for both planned major SSC experiments. The STS is physically a small part of the central tracking system and the calorimeter of the detector being proposed by the Solenoidal Detector Collaboration (SDC). Despite its seemingly small size, it occupies a volume of more than 5 meters in length and 1 meter in diameter and is an order of magnitude larger than any silicon detector system previously built. The STS will consist of silicon microstrip detectors and possibly silicon pixel detectors. The other two components are an outer barrel tracker, which will consist of straw tubes or scintillating fibers; and an outer intermediate angle tracker, which will consist of gas microstrips. The components are designed to work as an integrated system. Each componenet has specific strengths, but is individually incapable of providing the overall performance required by the physics goals of the SSC. The large particle fluxes, the short times between beam crossing, the high channel count, and the required very high position measurement accuracy pose challenging problems that must be solved. Furthermore, to avoid degrading the measurements, the solutions must be achieved using only a minimal amount of material. An additional constraint is that only low-Z materials are allowed. If that were not difficlut enough, the solutions must also be affordable

  4. The ALICE Silicon Pixel Detector System (SPD)

    CERN Document Server

    Kluge, A; Antinori, Federico; Burns, M; Cali, I A; Campbell, M; Caselle, M; Ceresa, S; Dima, R; Elias, D; Fabris, D; Krivda, Marian; Librizzi, F; Manzari, Vito; Morel, M; Moretto, Sandra; Osmic, F; Pappalardo, G S; Pepato, Adriano; Pulvirenti, A; Riedler, P; Riggi, F; Santoro, R; Stefanini, G; Torcato De Matos, C; Turrisi, R; Tydesjo, H; Viesti, G; PH-EP

    2007-01-01

    The ALICE silicon pixel detector (SPD) comprises the two innermost layers of the ALICE inner tracker system. The SPD includes 120 detector modules (half-staves) each consisting of 10 ALICE pixel chips bump bonded to two silicon sensors and one multi-chip read-out module. Each pixel chip contains 8192 active cells, so that the total number of pixel cells in the SPD is ≈ 107. The on-detector read-out is based on a multi-chip-module containing 4 ASICs and an optical transceiver module. The constraints on material budget and detector module dimensions are very demanding.

  5. Matrix-encapsulated waste forms: application to idealized systems, commercial and SRP/INEL wastes, hydrated radiophases and encapsulant phases

    International Nuclear Information System (INIS)

    Roy, R.; Vance, E.R.; McCarthy, G.J.; White, W.B.

    1981-01-01

    This paper describes the encapsulation strategy as applied to microscopic-scale encapsulation in ceramics composed of micron-sized grains of possibly more leachable radiophases intimately surrounded by micron-sized grains of more insoluble phases. The encapsulation approach should be valid, almost axiomatic, for defense waste. However, there are still problems to be investigated experimentally. These are (a) because of the dilution, it is difficult to confirm the geometry of the radionuclide-bearing phases relative to that of the matrix: one almost has to use the inverse approach by making leach measurements, (b) deciding between using the highly reactive oxyhydroxide sludges themselves or sintered calcine to be coated, (c) verification of the insolubility of the encapsulant phases in a variety of groundwaters, and (d) the production of ceramics of near-zero porosity, using hot-isostatic pressing, or incorporation in either silicate or phosphate cements

  6. Development of PLGA–PEG encapsulated miltefosine based drug delivery system against visceral leishmaniasis

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Rishikesh; Sahoo, Ganesh Chandra [Biomedical and Nanomedicine Department, Rajendra Memorial Research Institute Medical Science (ICMR) (India); Pandey, Krishna; Das, V.N.R.; Topno, Roshan K. [Clinical Medicine Department, Rajendra Memorial Research Institute Medical Science (ICMR) (India); Ansari, Md Yousuf [Pharmacoinformatics Department, National Institute Pharmaceutica Research and Education Industrial Area, Hajipur (India); Rana, Sindhuprava [Biomedical and Nanomedicine Department, Rajendra Memorial Research Institute Medical Science (ICMR) (India); Das, Pradeep [Molecular Biology Department, Rajendra Memorial Research Institute Medical Science (ICMR) (India)

    2016-02-01

    Targeted drug delivery systems are ideal technology to increase the maximum mechanism of action with smaller dose, we have developed miltefosine encapsulated PLGA–PEG nanoparticles (PPEM) to target macrophage of infected tissues against Leishmania donovani. The structural characterization of PLGA–PEG by transmission electron microscopy (TEM) has shown a size range of 10 to 15 nm. Synthesis and drug encapsulation confirmed by dynamic light scattering (DLS) and Fourier transform infrared spectroscopy (FTIR) and confirmed NP encapsulation. The dose of nano encapsulated miltefosine decreased by fifty percent as compared to that of a conventional miltefosine and Amphoterecin B. The inhibition of amastigotes in the splenic tissue with nano encapsulated miltefosine (23.21 ± 23) was significantly more than the conventional miltefosine (89.22 ± 52.7) and Amphoterecin B (94.12 ± 55.1). This study signifies that there is an increased contact surface area of the nano encapsulated drug and significant reduction in size, improved the efficacy in both in vitro and in vivo study than that of the conventional miltefosine, Amphoterecin B. - Graphical abstract: The analyses of detailed structure characterized by TEM and DLS confirmed the nano-size of the particle 10–20 nm and FTIR confirmed for antileishmanial drug encapsulation in to PLGA–PEG. The dose of miltefosine is decreased by fifty percent as the IC50 value is decreased from 0.2 to 0.1 μg. Further inhibitions of amastigotes in the splenic tissue with these nanoparticles are significantly more than the conventional miltefosine and PLGA–PEG encapsulated Amphoterecin B (23.21 ± 23/89.09 ± 52.7/92.12 ± 55.1). - Highlights: • Synthesis of PLGA-PEG encapsulated miltefosine nanoparticles has been done. • An IC50 value of PPEM (0.1 ug/ml), miltefosine (0.2 μg/ml) and AmpB (1 μg/ml) were observed two fold better efficacies. • Inhibition of amastigotes of PPEM (23.21 ± 23) was significantly more than

  7. ATLAS silicon microstrip detector system (SCT)

    International Nuclear Information System (INIS)

    Unno, Y.

    2003-01-01

    The S CT together with the pixel and the transition radiation tracker systems and with a central solenoid forms the central tracking system of the ATLAS detector at LHC. Series production of SCT Silicon microstrip sensors is near completion. The sensors have been shown to be robust against high voltage operation to the 500 V required after fluences of 3x10 14 protons/cm 2 . SCT barrel modules are in series production. A low-noise CCD camera has been used to debug the onset of leakage currents

  8. Cabling for an SSC silicon tracking system

    International Nuclear Information System (INIS)

    Ziock, H.; Boissevain, J.; Cooke, B.; Miller, W.

    1990-01-01

    As part of the Superconducting Super Collider Laboratory (SSCL) funded silicon tracking subsystem R ampersand D program, we examine the problems associated with cabling such a system. Different options for the cabling plant are discussed. A silicon microstrip tracking detector for an SSC experiment is an extremely complex system. The system consists of approximately 10 7 detector channels, each of which requires a communication link with the outside world and connections to the detector bias voltage supply, to a DC power supply for the onboard electronics, and to an adjustable discrimination level. The large number of channels and the short time between beam interactions (16 nanoseconds) dictates the need for high speed and large bandwidth communication channels, and a power distribution system that can handle the high current draw of the electronics including the large AC component due to their switching. At the same time the constraints imposed by the physics measurements require that the cable plant have absolutely minimal mass and radiation length. 4 refs., 2 figs

  9. Personnel protective equipment total-encapsulating suit decontamination study using shower systems

    International Nuclear Information System (INIS)

    Menkhaus, D.E.

    1991-01-01

    This report documents an experimental evaluation, conducted at the Idaho National Engineering Laboratory, of a shower-based decontamination station for personnel wearing a Level A, total- encapsulating, chemical-protective suit. The decontamination station is used by personnel when egressing a dry, dusty environment contaminated with transuranic radionuclides. This system has the potential to minimize the risk of spreading the contaminants to clean areas. Two types of shower systems were evaluated, a drench shower and a multi-nozzle shower. A total-encapsulating suit, worn by personnel. was contaminated with soil containing 239 Pu. Pre- shower and post-shower contamination samples were collected and visual observations were made to evaluate the ability of the shower system to remove the contaminated dust and to obtain baseline data useful in designing a shower-based personnel decontamination system. 12 figs., 7 tabs

  10. Recovery of reactor electrical assemblies using differential de-encapsulation to remove dielectric insulation systems

    International Nuclear Information System (INIS)

    Hubrig, J.G.; Hammerstone, E.B.

    1986-01-01

    State-of-the-art de-encapsulation technologies associated with the conventional dielectric insulation systems employed in the construction of electrical coils and power distribution systems do not allow for accurate fatigue/failure analysis or reliable recovery of costly assembly components. Differential de-encapsulation allows for the selective removal of contemporary thermoset resin based insulation systems to allow non-destructive penetration of insulation wall thicknesses to both examine critical areas and recover high performance metallic and non-metallic inserts for remanufacture; significantly reducing replacement costs and reactor downtime. The authors' analysis describes how the availability of engineering data from the selective and non-destructive removal of insulation materials will aid in the evaluation of original manufacture, materials and procedures; enabling redesign to enhance subsequent on line performance. They also discuss why the ability to recover coil and core assemblies for remanufacture will have a major economic impact on reactor management costs

  11. A data acquisition system for silicon microstrip detectors

    International Nuclear Information System (INIS)

    Adriani, O.; Civinini, C.; D'Alessandro, R.; Meschini, M.; Pieri, M.; Castellini, G.

    1998-01-01

    Following initial work on the readout of the L3 silicon microvertex detector, the authors have developed a complete data acquisition system for silicon microstrip detectors for use both in their home institute and at the various test beam facilities at the CERN laboratory. The system uses extensive decoupling schemes allowing a fully floating connection to the detector. This feature has many advantages especially in the readout of the latest double-sided silicon microstrip detectors

  12. Encapsulation systems for the delivery of hydrophilic nutraceuticals: Food application.

    Science.gov (United States)

    Aditya, N P; Espinosa, Yadira Gonzalez; Norton, Ian T

    2017-07-01

    Increased health risk associated with the sedentary life style is forcing the food manufacturers to look for food products with specific or general health benefits e.g. beverages enriched with nutraceuticals like catechin, curcumin rutin. Compounds like polyphenols, flavonoids, vitamins are the good choice of bioactive compounds that can be used to fortify the food products to enhance their functionality. However due to low stability and bioavailability of these bioactives (both hydrophobic and hydrophilic) within the heterogeneous food microstructure and in the Gastro Intestinal Tract (GIT), it becomes extremely difficult to pass on the real health benefits to the consumers. Recent developments in the application of nano-delivery systems for food product development is proving to be a game changer which has raised the expectations of the researchers, food manufacturers and consumers regarding possibility of enhancing the functionality of bioactives within the fortified food products. In this direction, nano/micro delivery systems using lipids, surfactants and other materials (carbohydrates, polymers, complexes, protein) have been fabricated to stabilize and enhance the biological activity of the bioactive compounds. In the present review, current status of the various delivery systems that are used for the delivery of hydrophilic bioactives and future prospects for using other delivery systems that have been not completely explored for the delivery of hydrophilic bioactives e.g. niosomes; bilosomes, cubosomes are discussed. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. The GLAST silicon-strip tracking system

    International Nuclear Information System (INIS)

    Johnson, Robert P.

    2000-01-01

    The GLAST instrument concept is a gamma-ray pair conversion telescope that uses silicon microstrip detector technology to track the electron-positron pairs resulting from gamma-ray conversions in thin lead foils. A cesium iodide calorimeter following the tracker is used to measure the gamma-ray energy. Silicon strip technology is mature and robust, with an excellent heritage in space science and particle physics. It has many characteristics important for optimal performance of a pair conversion telescope, including high efficiency in thin detector planes, low noise, and excellent resolution and two-track separation. The large size of GLAST and high channel count in the tracker puts demands on the readout technology to operate at very low power, yet with sufficiently low noise occupancy to allow self triggering. A prototype system employing custom-designed ASIC's has been built and tested that meets the design goal of approximately 200 W per channel power consumption with a noise occupancy of less than one hit per trigger per 10,000 channels. Detailed design of the full-scale tracker is well advanced, with non-flight prototypes built for all components, and a complete 50,000 channel engineering demonstration tower module is currently under construction and will be tested in particle beams in late 1999. The flight-instrument conceptual design is for a 4x4 array of tower modules with an aperture of 2.9 m2 and an effective area of greater than 8000 cm2

  14. The GLAST Silicon-Strip Tracking System

    International Nuclear Information System (INIS)

    Johnson, R

    2004-01-01

    The GLAST instrument concept is a gamma-ray pair conversion telescope that uses silicon microstrip detector technology to track the electron-positron pairs resulting from gamma ray conversions in thin lead foils. A cesium iodide calorimeter following the tracker is used to measure the gamma-ray energy. Silicon strip technology is mature and robust, with an excellent heritage in space science and particle physics. It has many characteristics important for optimal performance of a pair conversion telescope, including high efficiency in thin detector planes, low noise, and excellent resolution and two-track separation. The large size of GLAST and high channel count in the tracker puts demands on the readout technology to operate at very low power, yet with sufficiently low noise occupancy to allow self triggering. A prototype system employing custom-designed ASIC's has been built and tested that meets the design goal of approximately 200 (micro)W per channel power consumption with a noise occupancy of less than one hit per trigger per 10,000 channels. Detailed design of the full-scale tracker is well advanced, with non-flight prototypes built for all components, and a complete 50,000 channel engineering demonstration tower module is currently under construction and will be tested in particle beams in late 1999. The flight-instrument conceptual design is for a 4 x 4 array of tower modules with an aperture of 2.9 m 2 and an effective area of greater than 8000 cm 2

  15. Muon tracking system with Silicon Photomultipliers

    International Nuclear Information System (INIS)

    Arneodo, F.; Benabderrahmane, M.L.; Dahal, S.; Di Giovanni, A.; Pazos Clemens, L.; Candela, A.; D'Incecco, M.; Sablone, D.; Franchi, G.

    2015-01-01

    We report the characterisation and performance of a low cost muon tracking system consisting of plastic scintillator bars and Silicon Photomultipliers equipped with a customised front-end electronics based on a fast preamplifier network. This system can be used as a detector test bench for astroparticle physics and for educational and outreach purposes. We investigated the device behaviour in self-trigger and coincidence mode, without using LED and pulse generators, showing that with a relatively simple set up a complete characterisation work can be carried out. A high definition oscilloscope, which can easily be found in many university physics or engineering departments, has been used for triggering and data acquisition. Its capabilities have been exploited to discriminate real particles from the background

  16. Muon tracking system with Silicon Photomultipliers

    Energy Technology Data Exchange (ETDEWEB)

    Arneodo, F.; Benabderrahmane, M.L.; Dahal, S. [New York University Abu Dhabi, Abu Dhabi (United Arab Emirates); Di Giovanni, A., E-mail: adriano.digiovanni@nyu.edu [New York University Abu Dhabi, Abu Dhabi (United Arab Emirates); Pazos Clemens, L. [New York University Abu Dhabi, Abu Dhabi (United Arab Emirates); Candela, A.; D' Incecco, M.; Sablone, D. [Gran Sasso National Laboratory of INFN, Assergi (Italy); Franchi, G. [AGE Scientific Srl, Capezzano Pianore (Italy)

    2015-11-01

    We report the characterisation and performance of a low cost muon tracking system consisting of plastic scintillator bars and Silicon Photomultipliers equipped with a customised front-end electronics based on a fast preamplifier network. This system can be used as a detector test bench for astroparticle physics and for educational and outreach purposes. We investigated the device behaviour in self-trigger and coincidence mode, without using LED and pulse generators, showing that with a relatively simple set up a complete characterisation work can be carried out. A high definition oscilloscope, which can easily be found in many university physics or engineering departments, has been used for triggering and data acquisition. Its capabilities have been exploited to discriminate real particles from the background.

  17. Multifunctional epitaxial systems on silicon substrates

    Energy Technology Data Exchange (ETDEWEB)

    Singamaneni, Srinivasa Rao, E-mail: ssingam@ncsu.edu [Department of Materials Science and Engineering, North Carolina State University, Raleigh, North Carolina 27695 (United States); Materials Science Division, Army Research Office, Research Triangle Park, North Carolina 27709 (United States); Department of Physics, The University of Texas at El Paso, El Paso, Texas 79968 (United States); Prater, John Thomas [Department of Materials Science and Engineering, North Carolina State University, Raleigh, North Carolina 27695 (United States); Materials Science Division, Army Research Office, Research Triangle Park, North Carolina 27709 (United States); Narayan, Jagdish [Department of Materials Science and Engineering, North Carolina State University, Raleigh, North Carolina 27695 (United States)

    2016-09-15

    Multifunctional heterostructures can exhibit a wide range of functional properties, including colossal magneto-resistance, magnetocaloric, and multiferroic behavior, and can display interesting physical phenomena including spin and charge ordering and strong spin-orbit coupling. However, putting this functionality to work remains a challenge. To date, most of the work reported in the literature has dealt with heterostructures deposited onto closely lattice matched insulating substrates such as DyScO{sub 3}, SrTiO{sub 3} (STO), or STO buffered Si(100) using concepts of lattice matching epitaxy (LME). However, strain in heterostructures grown by LME is typically not fully relaxed and the layers contain detrimental defects such as threading dislocations that can significantly degrade the physical properties of the films and adversely affect the device characteristics. In addition, most of the substrates are incompatible with existing CMOS-based technology, where Si (100) substrates dominate. This review discusses recent advances in the integration of multifunctional oxide and non-oxide materials onto silicon substrates. An alternative thin film growth approach, called “domain matching epitaxy,” is presented which identifies approaches for minimizing lattice strain and unwanted defects in large misfit systems (7%–25% and higher). This approach broadly allows for the integration of multifunctional materials onto silicon substrates, such that sensing, computation, and response functions can be combined to produce next generation “smart” devices. In general, pulsed laser deposition has been used to epitaxially grow these materials, although the concepts developed here can be extended to other deposition techniques, as well. It will be shown that TiN and yttria-stabilized zirconia template layers provide promising platforms for the integration of new functionality into silicon-based computer chips. This review paper reports on a number of thin

  18. The CDF-II silicon tracking system

    Energy Technology Data Exchange (ETDEWEB)

    F. Palmonari et al.

    2002-01-18

    The CDFII silicon tracking system, SVX, for Run II of the Fermilab Tevatron has up to 8 cylindrical layers with average radii spanning from {approx} (1.5 to 28.7) cm, and lengths ranging from {approx} (90 to 200) cm for a total active-area of {approx} 6 m{sup 2} and {approx} 7.2 x 10{sup 5} readout channels. SVX will improve the CDFII acceptance and efficiency for both B and high-Pt physics dependent upon b-tagging. Along with the description of the SVX we report some alignment survey data from the SVX assembly phase and the actual status of the alignment as it results from the offline data analysis. The problems encountered are also reviewed.

  19. Irinotecan-encapsulated double-reverse thermosensitive nanocarrier system for rectal administration.

    Science.gov (United States)

    Din, Fakhar Ud; Choi, Ju Yeon; Kim, Dong Wuk; Mustapha, Omer; Kim, Dong Shik; Thapa, Raj Kumar; Ku, Sae Kwang; Youn, Yu Seok; Oh, Kyung Taek; Yong, Chul Soon; Kim, Jong Oh; Choi, Han-Gon

    2017-11-01

    Intravenously administered for the treatment of rectum cancer, irinotecan produces severe side effects due to very high plasma concentrations. A novel irinotecan-encapsulated double reverse thermosensitive nanocarrier system (DRTN) for rectal administration was developed as an alternative. The DRTN was fabricated by dispersing the thermosensitive irinotecan-encapsulated solid lipid nanoparticles (SLN) in the thermosensitive poloxamer solution. Its gel properties, pharmacokinetics, morphology, anticancer activity and immunohistopathology were assessed after its rectal administration to rats and tumor-bearing mice. In the DRTN, the solid form of the SLN and the liquid form of the poloxamer solution persisted at 25 °C; the former melted to liquid, and the latter altered to gel at 36.5 °C. The DRTN was easily administered to the anus, gelling rapidly and strongly after rectal administration. Compared to the conventional hydrogel and intravenously administered solution, it retarded dissolution and initial plasma concentration. The DRTN gave sustained release and nearly constant plasma concentrations of irinotecan at 1-3 h in rats, resulting in improved anticancer activity. It induced no damage to the rat rectum and no body weight loss in tumor-bearing mice. Thus, this irinotecan-encapsulated DRTN associated with a reduced burst effect, lack of toxicity and excellent antitumor efficacy would be strongly recommended as a rectal pharmaceutical product alternative to commercial intravenous injection in the treatment of rectum and colon cancer.

  20. Dynamics of electrochemical lithiation/delithiation of graphene-encapsulated silicon nanoparticles studied by in-situ TEM.

    Science.gov (United States)

    Luo, Langli; Wu, Jinsong; Luo, Jiayan; Huang, Jiaxing; Dravid, Vinayak P

    2014-01-24

    The incorporation of nanostructured carbon has been recently reported as an effective approach to improve the cycling stability when Si is used as high-capacity anodes for the next generation Li-ion battery. However, the mechanism of such notable improvement remains unclear. Herein, we report in-situ transmission electron microscopy (TEM) studies to directly observe the dynamic electrochemical lithiation/delithiation processes of crumpled graphene-encapsulated Si nanoparticles to understand their physical and chemical transformations. Unexpectedly, in the first lithiation process, crystalline Si nanoparticles undergo an isotropic to anisotropic transition, which is not observed in pure crystalline and amorphous Si nanoparticles. Such a surprising phenomenon arises from the uniformly distributed localized voltage around the Si nanoparticles due to the highly conductive graphene sheets. It is observed that the intimate contact between graphene and Si is maintained during volume expansion/contraction. Electrochemical sintering process where small Si nanoparticles react and merge together to form large agglomerates following spikes in localized electric current is another problem for batteries. In-situ TEM shows that graphene sheets help maintain the capacity even in the course of electrochemical sintering. Such in-situ TEM observations provide valuable phenomenological insights into electrochemical phenomena, which may help optimize the configuration for further improved performance.

  1. Charge effect of a liposomal delivery system encapsulating simvastatin to treat experimental ischemic stroke in rats

    Directory of Open Access Journals (Sweden)

    Campos-Martorell M

    2016-06-01

    Full Text Available Mireia Campos-Martorell,1 Mary Cano-Sarabia,2 Alba Simats,1 Mar Hernández-Guillamon,1 Anna Rosell,1 Daniel Maspoch,2,3 Joan Montaner1,4 1Neurovascular Research Laboratory, Institut de Recerca Vall d’Hebron, Universitat Autònoma de Barcelona, Barcelona, 2Catalan Institute of Nanoscience and Nanotechnology (ICN2, CSIC and The Barcelona Institute of Science and Technology, Universitat Autònoma de Barcelona, Barcelona, 3Institució Catalana de Recerca i Estudis Avançats (ICREA, 4Neurovascular Unit, Department of Neurology, Universitat Autònoma de Barcelona, Hospital Vall d’Hebron, Barcelona, Spain Background and aims: Although the beneficial effects of statins on stroke have been widely demonstrated both in experimental studies and in clinical trials, the aim of this study is to prepare and characterize a new liposomal delivery system that encapsulates simvastatin to improve its delivery into the brain. Materials and methods: In order to select the optimal liposome lipid composition with the highest capacity to reach the brain, male Wistar rats were submitted to sham or transitory middle cerebral arterial occlusion (MCAOt surgery and treated (intravenous [IV] with fluorescent-labeled liposomes with different net surface charges. Ninety minutes after the administration of liposomes, the brain, blood, liver, lungs, spleen, and kidneys were evaluated ex vivo using the Xenogen IVIS® Spectrum imaging system to detect the load of fluorescent liposomes. In a second substudy, simvastatin was assessed upon reaching the brain, comparing free and encapsulated simvastatin (IV administration. For this purpose, simvastatin levels in brain homogenates from sham or MCAOt rats at 2 hours or 4 hours after receiving the treatment were detected through ultra-high-protein liquid chromatography. Results: Whereas positively charged liposomes were not detected in brain or plasma 90 minutes after their administration, neutral and negatively charged liposomes

  2. Encapsulation by Janus spheroids

    OpenAIRE

    Li, Wei; Liu, Ya; Brett, Genevieve; Gunton, James D.

    2011-01-01

    The micro/nano encapsulation technology has acquired considerable attention in the fields of drug delivery, biomaterial engineering, and materials science. Based on recent advances in chemical particle synthesis, we propose a primitive model of an encapsulation system produced by the self-assembly of Janus oblate spheroids, particles with oblate spheroidal bodies and two hemi-surfaces coded with dissimilar chemical properties. Using Monte Carlo simulation, we investigate the encapsulation sys...

  3. Stability of free and encapsulated Lactobacillus acidophilus ATCC 4356 in yogurt and in an artificial human gastric digestion system.

    Science.gov (United States)

    Ortakci, F; Sert, S

    2012-12-01

    The objective of this study was to determine the effect of encapsulation on survival of probiotic Lactobacillus acidophilus ATCC 4356 (ATCC 4356) in yogurt and during artificial gastric digestion. Strain ATCC 4356 was added to yogurt either encapsulated in calcium alginate or in free form (unencapsulated) at levels of 8.26 and 9.47 log cfu/g, respectively, and the influence of alginate capsules (1.5 to 2.5mm) on the sensorial characteristics of yogurts was investigated. The ATCC 4356 strain was introduced into an artificial gastric solution consisting of 0.08 N HCl (pH 1.5) containing 0.2% NaCl or into artificial bile juice consisting of 1.2% bile salts in de Man, Rogosa, and Sharpe broth to determine the stability of the probiotic bacteria. When incubated for 2h in artificial gastric juice, the free ATCC 4356 did not survive (reduction of >7 log cfu/g). We observed, however, greater survival of encapsulated ATCC 4356, with a reduction of only 3 log cfu/g. Incubation in artificial bile juice (6 h) did not significantly affect the viability of free or encapsulated ATCC 4356. Moreover, statistically significant reductions (~1 log cfu/g) of both free and encapsulated ATCC 4356 were observed during 4-wk refrigerated storage of yogurts. The addition of probiotic cultures in free or alginate-encapsulated form did not significantly affect appearance/color or flavor/odor of the yogurts. However, significant deficiencies were found in body/texture of yogurts containing encapsulated ATCC 4356. We concluded that incorporation of free and encapsulated probiotic bacteria did not substantially change the overall sensory properties of yogurts, and encapsulation in alginate using the extrusion method greatly enhanced the survival of probiotic bacteria against an artificial human gastric digestive system. Copyright © 2012 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  4. The LHCb Silicon Tracker - Control system specific tools and challenges

    CERN Document Server

    Adeva, G; Esperante Pereira, D; Gallas, A; Pazos Alvarez, A; Perez Trigo, E; Rodriguez Perez, P; Saborido, J; Amhis, Y; Bay, A; Blanc, F; Bressieux, J; Conti, G; Dupertuis, F; Fave, V; Frei, R; Gauvin, N; Haefeli, G; Keune, A; Luisier, J; Marki, R; Muresan, R; Nakada, T; Needham, M; Knecht, M; Schneider, O; Tran, M; Anderson, J; Buechler, A; Bursche, A; Chiapolini, N; De Cian, M; Elsasser, C; Salzmann, C; Saornil Gamarra, S; Steiner, S; Steinkamp, O; Straumann, U; van Tilburg, J; Tobin, M; Vollhardt, A; Aquines Gutierrez, O; Bauer, C; Britsch, M; Maciuc, F; Schmelling, M; Voss, H; Iakovenko, V; Okhrimenko, O; Pugatch, V

    2014-01-01

    The Experiment Control System (ECS) of the LHCb Silicon Tracker sub-detectors is built on the integrated LHCb ECS framework. Although all LHCb sub-detectors use the same framework and follow the same guidelines, the Silicon Tracker control system uses some interesting additional features in terms of operation and monitoring. The main details are described in this document. Since its design, the Silicon Tracker control system has been continuously evolving in a quite disorganized way. Some major maintenance activities are required to be able to keep improving. A description of those activities can also be found here.

  5. Encapsulation of Polymethoxyflavones in Citrus Oil Emulsion-Based Delivery Systems.

    Science.gov (United States)

    Yang, Ying; Zhao, Chengying; Chen, Jingjing; Tian, Guifang; McClements, David Julian; Xiao, Hang; Zheng, Jinkai

    2017-03-01

    The purpose of this work was to elucidate the effects of citrus oil type on polymethoxyflavone (PMF) solubility and on the physicochemical properties of PMF-loaded emulsion-based delivery systems. Citrus oils were extracted from mandarin, orange, sweet orange, and bergamot. The major constituents were determined by GC/MS: sweet orange oil (97.4% d-limonene); mandarin oil (72.4% d-limonene); orange oil (67.2% d-limonene); and bergamot oil (34.6% linalyl acetate and 25.3% d-limonene). PMF-loaded emulsions were fabricated using 10% oil phase (containing 0.1% w/v nobiletin or tangeretin) and 90% aqueous phase (containing 1% w/v Tween 80) using high-pressure homogenization. Delivery systems prepared using mandarin oil had the largest mean droplet diameters (386 or 400 nm), followed by orange oil (338 or 390 nm), bergamot oil (129 or 133 nm), and sweet orange oil (122 or 126 nm) for nobiletin- or tangeretin-loaded emulsions, respectively. The optical clarity of the emulsions increased with decreasing droplet size due to reduced light scattering. The viscosities of the emulsions (with or without PMFs) were similar (1.3 to 1.4 mPa·s), despite appreciable differences in oil phase viscosity. The loading capacity and encapsulation efficiency of the emulsions depended on carrier oil type, with bergamot oil giving the highest loading capacity. In summary, differences in the composition and physical characteristics of citrus oils led to PMF-loaded emulsions with different encapsulation and physicochemical characteristics. These results will facilitate the rational design of emulsion-based delivery systems for encapsulation of PMFs and other nutraceuticals in functional foods and beverages.

  6. Transport of encapsulated nuclear fuels

    International Nuclear Information System (INIS)

    Broman, Ulrika; Dybeck, Peter; Ekendahl, Ann-Mari

    2005-12-01

    The transport system for encapsulated fuel is described, including a preliminary drawing of a transport container. In the report, the encapsulation plant is assumed to be located to Oskarshamn, and the repository to Oskarshamn or Forsmark

  7. Development of Magnesium Silicate Hydrate cement system for nuclear waste encapsulation

    International Nuclear Information System (INIS)

    Zhang, T.; Vandeperre, L.J.; Cheeseman, C.R.

    2012-01-01

    A novel low pH cement system for encapsulating nuclear industry wastes containing aluminium has been developed using blends of MgO and silica fume (SF). Identification of the hydrated phases in MgO/silica fume samples showed that brucite formed in early stages of hydration and then reacted with the silica fume to produce a magnesium silicate hydrate (M-S-H) gel phase. When all brucite reacts with silica fume a cement system with an equilibrium pH just below 10 was achieved. Selected mixes have been characterized for hydration reactions, setting time and strength development. Mortar samples with w/s ratios of 0.5 and 50% by weight of sand added achieved compressive strengths in excess of 95 MPa after 28 days. The addition of MgCO 3 buffered the early pH and the addition of fine sand particles eliminated shrinkage cracking. The interaction of the optimised mortar with Al metal has been investigated. Al metal strips were firmly bound into the MgO:SF:sand samples and no H 2 gas detected, and this indicates that the novel systems developed in this work have potential for encapsulating certain types of problematic legacy wastes from the nuclear industry. (authors)

  8. Food-grade micro-encapsulation systems that may induce satiety via delayed lipolysis: A review.

    Science.gov (United States)

    Corstens, Meinou N; Berton-Carabin, Claire C; de Vries, Renko; Troost, Freddy J; Masclee, Ad A M; Schroën, Karin

    2017-07-03

    The increasing prevalence of overweight and obesity requires new, effective prevention and treatment strategies. One approach to reduce energy intake is by developing novel foods with increased satiating properties, which may be accomplished by slowing down lipolysis to deliver substrates to the ileum, thereby enhancing natural gut-brain signaling pathways of satiety that are normally induced by meal intake. To develop slow release food additives, their processing in the gastrointestinal tract has to be understood; therefore, we start from a general description of the digestive system and relate that to in vitro modeling, satiety, and lipolytic mechanisms. The effects of physicochemical lipid composition, encapsulation matrix, and interfacial structure on lipolysis are emphasized. We give an overview of techniques and materials used, and discuss partitioning, which may be a key factor for encapsulation performance. Targeted release capsules that delay lipolysis form a real challenge because of the high efficiency of the digestive system; hardly any proof was found that intact orally ingested lipids can be released in the ileum and thereby induce satiety. We expect that this challenge could be tackled with structured o/w-emulsion-based systems that have some protection against lipase, e.g., by hindering bile salt adsorption and/or delaying lipase diffusion.

  9. Heterogeneous Silicon Photonics OFDR Sensing System, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Luna will team with Dr. John Bowers of UCSB to develop an Optical Frequency Domain Reflectometry (OFDR) system-on-chip using heterogeneous silicon photonics to...

  10. Development of polyherbal antidiabetic formulation encapsulated in the phospholipids vesicle system

    Directory of Open Access Journals (Sweden)

    Vinod Kumar Gauttam

    2013-01-01

    Full Text Available Multifactorial metabolic diseases, for instance diabetes develop several complications like hyperlipidemia, hepatic toxicity, immunodeficiency etc., Hence, instead of mono-drug therapy the management of the disease requires the combination of herbs. Marketed herbal drugs comprise of irrational combinations, which makes their quality control more difficult. Phytoconstituents, despite having excellent bioactivity in vitro demonstrate less or no in vivo actions due to their poor lipid solubility, resulting in high therapeutic dose regimen; phospholipids encapsulation can overcome this problem. Hence, present study was designed to develop a phospholipids encapsulated polyherbal anti-diabetic formulation. In the present study, polyherbal formulation comprises of lyophilized hydro-alcoholic (50% v/v extracts of Momordica charantia, Trigonella foenum-graecum and Withania somnifera 2:2:1, respectively, named HA, optimized based on oral glucose tolerance test model in normal Wistar rats. The optimized formulation (HA entrapped in the phosphatidylcholine and cholesterol (8:2 vesicle system is named HA lipids (HAL. The vesicles were characterized for shape, morphology, entrapment efficiency, polar-dispersity index and release profile in the gastric pH. The antidiabetic potential of HA, marketed polyherbal formulation (D-fit and HAL was compared in streptozotocin-induced diabetic rat model of 21 days study. The parameters evaluated were behavioral changes, body weight, serum glucose level, lipid profile and oxidative stress. The antidiabetic potential of HA (1000 mg/kg was at par with the D-fit (1000 mg/kg. However, the potential was enhanced by phospholipids encapsulation; as HAL (500 mg/kg has shown more significant (P < 0.05 potential in comparison to HA (1000 mg/kg and at par with metformin (500 mg/kg.

  11. An evaluation of the efficiency of compartmented alginate fibres encapsulating a rejuvenator as an asphalt pavement healing system

    NARCIS (Netherlands)

    Tabaković, Amir; Karač, Aleksandar; Schlangen, H.E.J.G.

    2017-01-01

    This paper explores the potential methods for evaluating a healing system for asphalt pavements. The healing system under investigation involves compartmented calcium-alginate fibres encapsulating an asphalt binder healing agent (rejuvenator). This system presents a novel method of incorporating

  12. Protein encapsulated magnetic carriers for micro/nanoscale drug delivery systems.

    Energy Technology Data Exchange (ETDEWEB)

    Xie, Y.; Kaminski, M. D.; Mertz, C. J.; Finck, M. R.; Guy, S. G.; Chen, H.; Rosengart, A. J.; Chemical Engineering; Univ. of Chicago, Pritzker School of Medicine

    2005-01-01

    Novel methods for drug delivery may be based on nanotechnology using non-invasive magnetic guidance of drug loaded magnetic carriers to the targeted site and thereafter released by external ultrasound energy. The key building block of this system is to successfully synthesize biodegradable, magnetic drug carriers. Magnetic carriers using poly(D,L-lactide-co-glycolide) (PLGA) or poly(lactic acid)-poly(ethylene glycol) (PLA-PEG) as matrix materials were loaded with bovine serum albumin (BSA) by a double-emulsion technique. BSA-loaded magnetic microspheres were characterized for size, morphology, surface charge, and magnetization. The BSA encapsulation efficiency was determined by recovering albumin from the microspheres using dimethyl sulfoxide and 0.05N NaOH/0.5% SDS then quantifying with the Micro-BCA protein assay. BSA release profiles were also determined by the Micro-BCA protein assay. The microspheres had drug encapsulation efficiencies up to 90% depending on synthesis parameters. Particles were spherical with a smooth or porous surface having a size range less than 5 {mu}m. The surface charge (expressed as zeta potential) was near neutral, optimal for prolonged intravascular survival. The magnetization of these BSA loaded magnetic carriers was 2 to 6 emu/g, depending on the specific magnetic materials used during synthesis.

  13. "Lollipop-shaped" high-sensitivity Microelectromechanical Systems vector hydrophone based on Parylene encapsulation

    Science.gov (United States)

    Liu, Yuan; Wang, Renxin; Zhang, Guojun; Du, Jin; Zhao, Long; Xue, Chenyang; Zhang, Wendong; Liu, Jun

    2015-07-01

    This paper presents methods of promoting the sensitivity of Microelectromechanical Systems (MEMS) vector hydrophone by increasing the sensing area of cilium and perfect insulative Parylene membrane. First, a low-density sphere is integrated with the cilium to compose a "lollipop shape," which can considerably increase the sensing area. A mathematic model on the sensitivity of the "lollipop-shaped" MEMS vector hydrophone is presented, and the influences of different structural parameters on the sensitivity are analyzed via simulation. Second, the MEMS vector hydrophone is encapsulated through the conformal deposition of insulative Parylene membrane, which enables underwater acoustic monitoring without any typed sound-transparent encapsulation. Finally, the characterization results demonstrate that the sensitivity reaches up to -183 dB (500 Hz 0dB at 1 V/ μPa ), which is increased by more than 10 dB, comparing with the previous cilium-shaped MEMS vector hydrophone. Besides, the frequency response takes on a sensitivity increment of 6 dB per octave. The working frequency band is 20-500 Hz and the concave point depth of 8-shaped directivity is beyond 30 dB, indicating that the hydrophone is promising in underwater acoustic application.

  14. The ALICE silicon pixel detector system

    International Nuclear Information System (INIS)

    Kapusta, S.

    2009-01-01

    The Large Hadron Collider (LHC) is again reaching its startup phase at the European Organization for Particle Physics (CERN). The LHC started its operation on the 10 th of September, 2008 with huge success managing to sent the the first beam successfully around the entire ring in less than an hour after the first injection in one direction, and later that day in the opposite direction. Unfortunately, on the 19 th of September, an accident occurred during the 5.5 TeV magnet commissioning in Sector 34, which will significantly delay the operation of the LHC. The ALICE experiment will exploit the collisions of accelerated ions produced at the LHC to study strongly interacting matter at extreme densities and high temperatures. e ALICE Silicon Pixel Detector (SPD) represents the two innermost layers of the ALICE Inner Traing System (ITS) located at radii of 3.9 cm and 7.6 cm from the Interaction Point (IP). One of the main tasks of the SPD is to provide precise traing information. is information is fundamental for the study of weak decays of heavy flavor particles, since the corresponding signature is a secondary vertex separated from the primary vertex only by a few hundred micrometers. e tra density could be as high as 80 tracks per cm 2 in the innermost SPD layer as a consequence of a heavy ion collision. The SPD will provide a spatial resolution of around ≅12 μm in the rφ direction and ≅70 μm in the z direction. The expected occupancy of the SPD ranges from 0.4% to 1.5% which makes it an excellent charged particle multiplicity detector in the pseudorapidity region |η| < 2. Furthermore, by combining all possible hits in the SPD, one can get a rough estimate of the position of the primary interaction. One of the challenges is the tight material budget constraint (<1% radiation length per layer) in order to limit the scattering of the traversing particles. e silicon sensor and its readout chip have a total thickness of only 350 μm and the signal lines from the

  15. Monocrystalline silicon solar cells applied in photovoltaic system

    OpenAIRE

    L.A. Dobrzański; A. Drygała; M. Giedroć; M. Macek

    2012-01-01

    Purpose: The aim of the paper is to fabricate the monocrystalline silicon solar cells using the conventional technology by means of screen printing process and to make of them photovoltaic system.Design/methodology/approach: The investigation of current – voltage characteristic to determinate basic electrical properties of monocrystalline silicon solar cells were investigated under Standard Test Condition. Photovoltaic module was produced from solar cells with the largest short-circuit curren...

  16. Silicon photonics design from devices to systems

    CERN Document Server

    Chrostowski, Lukas

    2015-01-01

    From design and simulation through to testing and fabrication, this hands-on introduction to silicon photonics engineering equips students with everything they need to begin creating foundry-ready designs. In-depth discussion of real-world issues and fabrication challenges ensures that students are fully equipped for careers in industry. Step-by-step tutorials, straightforward examples, and illustrative source code fragments guide students through every aspect of the design process, providing a practical framework for developing and refining key skills. Offering industry-ready expertise, the text supports existing PDKs for CMOS UV-lithography foundry services (OpSIS, ePIXfab, imec, LETI, IME and CMC) and the development of new kits for proprietary processes and clean-room based research. Accompanied by additional online resources to support students, this is the perfect learning package for senior undergraduate and graduate students studying silicon photonics design, and academic and industrial researchers in...

  17. Stepwise encapsulation and controlled two-stage release system for cis-Diamminediiodoplatinum.

    Science.gov (United States)

    Chen, Yun; Li, Qian; Wu, Qingsheng

    2014-01-01

    cis-Diamminediiodoplatinum (cis-DIDP) is a cisplatin-like anticancer drug with higher anticancer activity, but lower stability and price than cisplatin. In this study, a cis-DIDP carrier system based on micro-sized stearic acid was prepared by an emulsion solvent evaporation method. The maximum drug loading capacity of cis-DIDP-loaded solid lipid nanoparticles was 22.03%, and their encapsulation efficiency was 97.24%. In vitro drug release in phosphate-buffered saline (pH =7.4) at 37.5°C exhibited a unique two-stage process, which could prove beneficial for patients with tumors and malignancies. MTT (3-[4,5-dimethylthiazol-2-yl]-2, 5-diphenyltetrazolium bromide) assay results showed that cis-DIDP released from cis-DIDP-loaded solid lipid nanoparticles had better inhibition activity than cis-DIDP that had not been loaded.

  18. Serious systemic infection caused by non-encapsulated Haemophilus influenzae biotype III in an adult

    DEFF Research Database (Denmark)

    Lester, Anne; Pedersen, P B

    1991-01-01

    Haemophilus influenzae is the aetiological agent in less than 1% of septic arthritis cases in adults and most often serotype b is involved. We report here a case of severe systemic infection due to non-encapsulated H. influenzae biotype III in a 40-year-old man, previously healthy although alcohol...... abuser. Cholangitis and acute alcoholic hepatitis were diagnosed simultaneously. The organism was grown from blood and from synovial fluid of the left knee, but several other joints were also affected. The close relationship between H. influenzae biotype III and H. aegyptius is mentioned in view...... of recent reports of fatal childhood illness caused by a special clone of H. aegyptius and the importance of reporting both serotype and biotype in severe H. influenzae induced disease is emphasized....

  19. Silicon-based tracking system: Mechanical engineering and design

    International Nuclear Information System (INIS)

    Miller, W.O.; Gamble, M.T.; Thompson, T.C.; Woloshun, K.A.; Reid, R.S.; Hanlon, J.A.; Michaud, F.D.; Dransfield, G.D.; Ziock, H.J.; Palounek, A.P.

    1992-01-01

    The Silicon Tracking System (STS) is composed of silicon strip detectors arranged by both in a cylindrical array and an array of flat panels about the interaction region. The cylindrical array is denoted the central region and the flat panel arrays, which are normal to the beam axis, we denoted the forward regions. The overall length of the silicon array is 5.16 m and the maximum diameter is 0.93 m. The Silicon Tracking System Conceptual Design Report, should be consulted for the body of analysis performed to quantify the present design concept. For the STS to achieve its physics goals, the mechanical structures and services must support 17 m 2 of silicon detectors and stabilize their positions to within 5 μm, uniformly cool the detector the system to O degrees C and at the same time potentially remove up to 13 kW of waste heat generated by the detector electronics, provide up to 3400 A of current to supply the 6.5 million electronics channels, and supply of control and data transmission lines for those channels. These objectives must be achieved in a high ionizing radiation environment, using virtually no structural mass and only low-Z materials. The system must be maintainable during its 10 year operating life

  20. Silicone metalization

    Energy Technology Data Exchange (ETDEWEB)

    Maghribi, Mariam N. (Livermore, CA); Krulevitch, Peter (Pleasanton, CA); Hamilton, Julie (Tracy, CA)

    2008-12-09

    A system for providing metal features on silicone comprising providing a silicone layer on a matrix and providing a metal layer on the silicone layer. An electronic apparatus can be produced by the system. The electronic apparatus comprises a silicone body and metal features on the silicone body that provide an electronic device.

  1. Evaluation of nano encapsulation techniques in different polymeric system for the delivery of anti-tuberculosis drugs (ATD)

    CSIR Research Space (South Africa)

    Swai, H

    2006-02-01

    Full Text Available In this study, isoniazid, one of the most potent anti-TB drugs, was successfully encapsulated in poly (D, L- lactide-co-glycolide) (PLG) and in alginate-chitosan polymeric systems using a double-emulsion method and a cation-induced gelation method...

  2. Encapsulation methods for organic electrical devices

    Science.gov (United States)

    Blum, Yigal D.; Chu, William Siu-Keung; MacQueen, David Brent; Shi, Yijian

    2013-06-18

    The disclosure provides methods and materials suitable for use as encapsulation barriers in electronic devices. In one embodiment, for example, there is provided an electroluminescent device or other electronic device encapsulated by alternating layers of a silicon-containing bonding material and a ceramic material. The encapsulation methods provide, for example, electronic devices with increased stability and shelf-life. The invention is useful, for example, in the field of microelectronic devices.

  3. Theoretical study on the combined systems of peanut-shaped carbon nanotubes encapsulated in single-walled carbon nanotubes

    International Nuclear Information System (INIS)

    Wang, Guo; Huang, Yuanhe

    2012-01-01

    Highlights: ► The combined systems of peanut-shaped carbon nanotubes encapsulated in single-walled carbon nanotubes are investigated. ► The band structures and related electronic properties are calculated by using crystal orbital method. ► The carrier mobility and mean free path are evaluated under the deformation potential theory. -- Abstract: The combined systems of peanut-shaped carbon nanotubes encapsulated in both semiconducting and metallic single-walled carbon nanotubes are investigated by using self-consistent field crystal orbital method based on the density functional theory. The investigation indicates that the interaction between the two constituents is mainly contributed by the π orbitals. The encapsulation does not change the semiconducting or metallic nature of the single-walled carbon nanotubes, but significantly changes the band dispersion and decreases the frontier band width of the metallic one. The carrier mobility and mean free path of the metallic single-walled carbon nanotube increase greatly after the encapsulation. The calculated mobilities have the order of 10 3 cm 2 V −1 s −1 for both of the semiconducting and metallic double-walled carbon nanotubes.

  4. Challenging encapsulation in the design of high-risk control systems

    Science.gov (United States)

    Dvorak, D.

    2002-01-01

    An apporpriate architectural approach is to acknowledge the underlying physics and to elevate the concepts of state and models to first-class design elements that are not encapsulated within subsystem objects.

  5. The ALICE Silicon Pixel Detector Control and Calibration Systems

    CERN Document Server

    Calì, Ivan Amos; Manzari, Vito; Stefanini, Giorgio

    2008-01-01

    The work presented in this thesis was carried out in the Silicon Pixel Detector (SPD) group of the ALICE experiment at the Large Hadron Collider (LHC). The SPD is the innermost part (two cylindrical layers of silicon pixel detec- tors) of the ALICE Inner Tracking System (ITS). During the last three years I have been strongly involved in the SPD hardware and software development, construction and commissioning. This thesis is focused on the design, development and commissioning of the SPD Control and Calibration Systems. I started this project from scratch. After a prototyping phase now a stable version of the control and calibration systems is operative. These systems allowed the detector sectors and half-barrels test, integration and commissioning as well as the SPD commissioning in the experiment. The integration of the systems with the ALICE Experiment Control System (ECS), DAQ and Trigger system has been accomplished and the SPD participated in the experimental December 2007 commissioning run. The complex...

  6. Selective encapsulation by Janus particles

    Energy Technology Data Exchange (ETDEWEB)

    Li, Wei, E-mail: wel208@mrl.ucsb.edu [Materials Research Laboratory, University of California, Santa Barbara, California 93106 (United States); Ruth, Donovan; Gunton, James D. [Department of Physics, Lehigh University, Bethlehem, Pennsylvania 18015 (United States); Rickman, Jeffrey M. [Department of Physics, Lehigh University, Bethlehem, Pennsylvania 18015 (United States); Department of Materials Science and Engineering, Lehigh University, Bethlehem, Pennsylvania 18015 (United States)

    2015-06-28

    We employ Monte Carlo simulation to examine encapsulation in a system comprising Janus oblate spheroids and isotropic spheres. More specifically, the impact of variations in temperature, particle size, inter-particle interaction range, and strength is examined for a system in which the spheroids act as the encapsulating agents and the spheres as the encapsulated guests. In this picture, particle interactions are described by a quasi-square-well patch model. This study highlights the environmental adaptation and selectivity of the encapsulation system to changes in temperature and guest particle size, respectively. Moreover, we identify an important range in parameter space where encapsulation is favored, as summarized by an encapsulation map. Finally, we discuss the generalization of our results to systems having a wide range of particle geometries.

  7. Light propagation in one-dimensional porous silicon complex systems

    NARCIS (Netherlands)

    Oton, C.J.; Dal Negro, L.; Gaburro, Z.; Pavesi, L.; Johnson, P.J.; Lagendijk, Aart; Wiersma, D.S.

    2003-01-01

    We discuss the optical properties of one-dimensional complex dielectric systems, in particular the time-resolved transmission through thick porous silicon quasiperiodic multi-layers. Both in numerical calculations and experiments we find dramatic distortion effects, i.e. pulse stretching and

  8. Stepwise encapsulation and controlled two-stage release system for cis-Diamminediiodoplatinum

    Directory of Open Access Journals (Sweden)

    Chen Y

    2014-06-01

    Full Text Available Yun Chen,1,* Qian Li,1,2,* Qingsheng Wu1 1Department of Chemistry, Key Laboratory of Yangtze River Water Environment, Ministry of Education, Tongji University, Shanghai; 2Shanghai Institute of Quality Inspection and Technical Research, Shanghai, People’s Republic of China *These authors contributed equally to this work Abstract: cis-Diamminediiodoplatinum (cis-DIDP is a cisplatin-like anticancer drug with higher anticancer activity, but lower stability and price than cisplatin. In this study, a cis-DIDP carrier system based on micro-sized stearic acid was prepared by an emulsion solvent evaporation method. The maximum drug loading capacity of cis-DIDP-loaded solid lipid nanoparticles was 22.03%, and their encapsulation efficiency was 97.24%. In vitro drug release in phosphate-buffered saline (pH =7.4 at 37.5°C exhibited a unique two-stage process, which could prove beneficial for patients with tumors and malignancies. MTT (3-[4,5-dimethylthiazol-2-yl]-2, 5-diphenyltetrazolium bromide assay results showed that cis-DIDP released from cis-DIDP-loaded solid lipid nanoparticles had better inhibition activity than cis-DIDP that had not been loaded. Keywords: stearic acid, emulsion solvent evaporation method, drug delivery, cis-DIDP, in vitro

  9. Dental mesenchymal stem cells encapsulated in alginate hydrogel co-delivery microencapsulation system for cartilage regeneration

    Science.gov (United States)

    Moshaverinia, Alireza; Xu, Xingtian; Chen, Chider; Akiyama, Kentaro; Snead, Malcolm L; Shi, Songtao

    2013-01-01

    Dental-derived MSCs are promising candidates for cartilage regeneration, with high chondrogenic differentiation capacity. This property contributes to making dental MSCs an advantageous therapeutic option compared to current treatment modalities. The MSC delivery vehicle is the principal determinant for the success of MSC-mediated cartilage regeneration therapies. The objectives of this study were to: (1) develop a novel co-delivery system based on TGF-β1 loaded RGD-coupled alginate microspheres encapsulating Periodontal Ligament Stem Cells (PDLSCs) or Gingival Mesenchymal Stem Cells (GMSCs); and (2) investigate dental MSC viability and chondrogenic differentiation in alginate microspheres. The results revealed the sustained release of TGF-β1 from the alginate microspheres. After 4 weeks of chondrogenic differentiation in vitro, PDLSCs, GMSCs as well as human bone marrow mesenchymal stem cells (hBMMSC) (as positive control) revealed chondrogenic gene expression markers (Col II and Sox-9) via qPCR, as well as matrix positively stained by toluidine blue and safranin-O. In animal studies, ectopic cartilage tissue regeneration was observed inside and around the transplanted microspheres, confirmed by histochemical and immunofluorescent staining. Interestingly, PDLSCs showed more chondrogenesis than GMSCs and hBMMSCs (Palginate microencapsulating dental MSCs make a promising candidate for cartilage regeneration. Our results highlight the vital role played by the microenvironment, as well as value of presenting inductive signals for viability and differentiation of MSCs. PMID:23891740

  10. Nanoscale thermal imaging of dissipation in quantum systems and in encapsulated graphene

    Science.gov (United States)

    Halbertal, Dorri

    Energy dissipation is a fundamental process governing the dynamics of physical systems. In condensed matter physics, in particular, scattering mechanisms, loss of quantum information, or breakdown of topological protection are deeply rooted in the intricate details of how and where the dissipation occurs. Despite its vital importance the microscopic behavior of a system is usually not formulated in terms of dissipation because the latter is not a readily measureable quantity on the microscale. While the motivation is clear, existing thermal imaging methods lack the necessary sensitivity and are unsuitable for low temperature operation required for the study of quantum systems. We developed a superconducting quantum interference nano thermometer device with sub 50 nm diameter that resides at the apex of a sharp pipette and provides scanning cryogenic thermal sensing with four orders of magnitude improved thermal sensitivity of below 1 uK/sqrtHz. The noncontact noninvasive thermometry allows thermal imaging of very low nanoscale energy dissipation down to the fundamental Landauer limitý of 40 fW for continuous readout of a single qubit at 1 GHz at 4.2 K. These advances enable observation of dissipation due to single electron charging of individual quantum dots in carbon nanotubes, opening the door to direct imaging of nanoscale dissipation processes in quantum matter. In this talk I will describe the technique and present a study of hBN encapsulated graphene which reveals a novel dissipation mechanism due to atomic-scale resonant localized states at the edges of graphene. These results provide a direct valuable glimpse into the electron thermalization process in systems with weak electron-phonon interactions. Funded by European Research Council (ERC) under the European Union's Horizon 2020 programme (Grant No. 655416), Minerva Foundation with funding from the Federal German Ministry of Education and Research, Rosa and Emilio Segré Research Award, and the MISTI.

  11. A portable readout system for silicon microstrip sensors

    International Nuclear Information System (INIS)

    Marco-Hernandez, Ricardo

    2010-01-01

    This system can measure the collected charge in one or two microstrip silicon sensors by reading out all the channels of the sensor(s), up to 256. The system is able to operate with different types (p- and n-type) and different sizes (up to 3 cm 2 ) of microstrip silicon sensors, both irradiated and non-irradiated. Heavily irradiated sensors will be used at the Super Large Hadron Collider, so this system can be used to research the performance of microstrip silicon sensors in conditions as similar as possible to the Super Large Hadron Collider operating conditions. The system has two main parts: a hardware part and a software part. The hardware part acquires the sensor signals either from external trigger inputs, in case of a radioactive source setup is used, or from a synchronised trigger output generated by the system, if a laser setup is used. The software controls the system and processes the data acquired from the sensors in order to store it in an adequate format. The main characteristics of the system are described. Results of measurements acquired with n- and p-type detectors using both the laser and the radioactive source setup are also presented and discussed.

  12. Mobile encapsulation and volume reduction system for wet low-level wastes

    International Nuclear Information System (INIS)

    Buelt, J.L.

    1985-08-01

    This report describes the results of the program entitled ''A Preconceptual Study for a Transportable Vitrification Process''. The objective of the study is to determine the feasibility of a Mobile Encapsulation and Volume Reduction System (MEVS). The report contains design criteria, a preconceptual design of the system, a comparison of disposal costs with other solidification technologies, and an assessment of utility interests in the transportable volume reduction service MEVS can provide. The MEVS design employs the use of a joule-heated glass melter to convert the wet low-level wastes into glass. The process is self-sufficient, requiring no direct facility services or reactor personnel. It is capable of servicing one waste type from a minimum of three reactors. The design was used to prepare capital and operating cost estimates. The capital cost for the MEVS is $4,680,000, which includes all labor necessary for design, engineering, inspection, and licensing. The operating cost of the system for servicing a minimum of three reactors is $1,530,000/y for resins or $2,280,000/y for concentrated liquids. The cost estimates compared favorably to the more common solidification process of cementation. Total MEVS operating costs which include processing, transportation and burial, are $191 to $218/ft 3 waste, whereas quoted costs for cementation and disposal from reactor operators range from $155 to $350/ft 3 . The report concludes with the requirements for additional development, which can be accomplished for less than one sixth of the capital costs. The report also presents the results of an assessment conducted with utility representatives to obtain their expressions of interest in a service of this type

  13. Expansive failure reactions and their prevention in the encapsulation of phenol formaldehyde type ion exchange resins in cement based systems

    Energy Technology Data Exchange (ETDEWEB)

    Constable, M.; Howard, C.G.; Johnson, M.A.; Jolliffe, C.B. (AEA Decommissioning and Waste Management, Winfrith (United Kingdom)); Sellers, R.M. (Nuclear Electric plc, Barnwood (United Kingdom))

    1992-01-01

    Lewatit DN is a phenol formaldehyde based ion exchange resin used to remove radioactive caesium from liquid waste streams such as fuel cooling ponds and effluents. This paper presents the results of a study of the encapsulation of the bead form of the resin in cement with particular reference to the mechanisms of its interaction with the encapsulant. When incorporated in pure ordinary Portland cement (OPC) at loadings in excess of 15 wt % an unstable product results due to expansion of the systems and at higher waste loadings failure results after only a few days. Evidence from differential scanning calorimetry, X-ray diffraction and scanning electron microscopy all indicate the cause of the expansive reaction to be the formation of crystals of calcium salts around and within the resin beads. Addition of BFS and sodium hydroxide prevent the formation of these salts by removal of calcium hydroxide from the system in other reactions. (author).

  14. Reaching Grid Parity Using BP Solar Crystalline Silicon Technology: A Systems Class Application

    Energy Technology Data Exchange (ETDEWEB)

    Cunningham, Daniel W; Wohlgemuth, John; Carlson, David E; Clark, Roger F; Gleaton, Mark; Posbic, John P; Zahler, James

    2010-12-06

    The primary target market for this program was the residential and commercial PV markets, drawing on BP Solar's premium product and service offerings, brand and marketing strength, and unique routes to market. These two markets were chosen because: (1) in 2005 they represented more than 50% of the overall US PV market; (2) they are the two markets that will likely meet grid parity first; and (3) they are the two market segments in which product development can lead to the added value necessary to generate market growth before reaching grid parity. Federal investment in this program resulted in substantial progress toward the DOE TPP target, providing significant advancements in the following areas: (1) Lower component costs particularly the modules and inverters. (2) Increased availability and lower cost of silicon feedstock. (3) Product specifically developed for residential and commercial applications. (4) Reducing the cost of installation through optimization of the products. (5) Increased value of electricity in mid-term to drive volume increases, via the green grid technology. (6) Large scale manufacture of PV products in the US, generating increased US employment in manufacturing and installation. To achieve these goals BP Solar assembled a team that included suppliers of critical materials, automated equipment developers/manufacturers, inverter and other BOS manufacturers, a utility company, and University research groups. The program addressed all aspects of the crystalline silicon PV business from raw materials (particularly silicon feedstock) through installation of the system on the customers site. By involving the material and equipment vendors, we ensured that supplies of silicon feedstock and other PV specific materials like encapsulation materials (EVA and cover glass) will be available in the quantities required to meet the DOE goals of 5 to 10 GW of installed US PV by 2015 and at the prices necessary for PV systems to reach grid parity in 2015

  15. Encapsulated Ball Bearings for Rotary Micro Machines

    Science.gov (United States)

    2007-01-01

    occurrence as well as the overall tribological properties of the bearing mechanism. Firstly, the number of stainless steel balls influences not only the load...stacks.iop.org/JMM/17/S224 Abstract We report on the first encapsulated rotary ball bearing mechanism using silicon microfabrication and stainless steel balls...The method of capturing stainless steel balls within a silicon race to support a silicon rotor both axially and radially is developed for rotary micro

  16. System-level integration of active silicon photonic biosensors

    Science.gov (United States)

    Laplatine, L.; Al'Mrayat, O.; Luan, E.; Fang, C.; Rezaiezadeh, S.; Ratner, D. M.; Cheung, K.; Dattner, Y.; Chrostowski, L.

    2017-02-01

    Biosensors based on silicon photonic integrated circuits have attracted a growing interest in recent years. The use of sub-micron silicon waveguides to propagate near-infrared light allows for the drastic reduction of the optical system size, while increasing its complexity and sensitivity. Using silicon as the propagating medium also leverages the fabrication capabilities of CMOS foundries, which offer low-cost mass production. Researchers have deeply investigated photonic sensor devices, such as ring resonators, interferometers and photonic crystals, but the practical integration of silicon photonic biochips as part of a complete system has received less attention. Herein, we present a practical system-level architecture which can be employed to integrate the aforementioned photonic biosensors. We describe a system based on 1 mm2 dies that integrate germanium photodetectors and a single light coupling device. The die are embedded into a 16x16 mm2 epoxy package to enable microfluidic and electrical integration. First, we demonstrate a simple process to mimic Fan-Out Wafer-level-Packaging, which enables low-cost mass production. We then characterize the photodetectors in the photovoltaic mode, which exhibit high sensitivity at low optical power. Finally, we present a new grating coupler concept to relax the lateral alignment tolerance down to +/- 50 μm at 1-dB (80%) power penalty, which should permit non-experts to use the biochips in a"plug-and-play" style. The system-level integration demonstrated in this study paves the way towards the mass production of low-cost and highly sensitive biosensors, and can facilitate their wide adoption for biomedical and agro-environmental applications.

  17. Enhanced colonic delivery of ciclosporin A self-emulsifying drug delivery system encapsulated in coated minispheres.

    Science.gov (United States)

    Keohane, Kieran; Rosa, Mónica; Coulter, Ivan S; Griffin, Brendan T

    2016-01-01

    Investigate the potential of coated minispheres (SmPill®) to enhance localized Ciclosporin A (CsA) delivery to the colon. CsA self-emulsifying drug delivery systems (SEDDS) were encapsulated into SmPill® minispheres. Varying degrees of coating thickness (low, medium and high) were applied using ethylcellulose and pectin (E:P) polymers. In vitro CsA release was evaluated in simulated gastric and intestinal media. Bioavailability of CsA in vivo following oral administration to pigs of SmPill® minispheres was compared to Neoral® po and Sandimmun® iv in a pig model. CsA concentrations in blood and intestinal tissue were determined by HPLC-UV. In vitro CsA release from coated minispheres decreased with increasing coating thickness. A linear relationship was observed between in vitro CsA release and in vivo bioavailability (r(2) = 0.98). CsA concentrations in the proximal, transverse and distal colon were significantly higher following administration of SmPill®, compared to Neoral® po and Sandimmun® iv (p < 0.05). Analysis of transverse colon tissue subsections also revealed significantly higher CsA concentrations in the mucosa and submucosa using SmPill® minispheres (p < 0.05). Modulating E:P coating thickness controls release of CsA from SmPill® minispheres. Coated minispheres limited CsA release in the small intestine and enhanced delivery and uptake in the colon. These findings demonstrate clinical advantages of an oral coated minisphere-enabled CsA formulation in the treatment of inflammatory conditions of the large intestine.

  18. Preserving viability of Lactobacillus rhamnosus GG in vitro and in vivo by a new encapsulation system

    Science.gov (United States)

    Probiotics have shown beneficial effects on human health. To increase the efficacy of probiotic applications, we used Lactobacillus rhamnosus GG (LGG) as a probiotic model to investigate approaches to enhance the bioavailability of probiotics. LGG was encapsulated in hydrogel beads containing pectin...

  19. Quality assurance database for the CBM silicon tracking system

    Energy Technology Data Exchange (ETDEWEB)

    Lymanets, Anton [Physikalisches Institut, Universitaet Tuebingen (Germany); Collaboration: CBM-Collaboration

    2015-07-01

    The Silicon Tracking System is a main tracking device of the CBM Experiment at FAIR. Its construction includes production, quality assurance and assembly of large number of components, e.g., 106 carbon fiber support structures, 1300 silicon microstrip sensors, 16.6k readout chips, analog microcables, etc. Detector construction is distributed over several production and assembly sites and calls for a database that would be extensible and allow tracing the components, integrating the test data, monitoring the component statuses and data flow. A possible implementation of the above-mentioned requirements is being developed at GSI (Darmstadt) based on the FAIR DB Virtual Database Library that provides connectivity to common SQL-Database engines (PostgreSQL, Oracle, etc.). Data structure, database architecture as well as status of implementation are discussed.

  20. Silicon Detector System for High Rate EXAFS Applications.

    Science.gov (United States)

    Pullia, A; Kraner, H W; Siddons, D P; Furenlid, L R; Bertuccio, G

    1995-08-01

    A multichannel silicon pad detector for EXAFS (Extended X-ray Absorption Fine Structure) applications has been designed and built. The X-ray spectroscopic measurements demonstrate that an adequate energy resolution of 230 eV FWHM (corresponding to 27 rms electrons in silicon) can be achieved reliably at -35 °C. A resolution of 190 eV FWHM (corresponding to 22 rms electrons) has been obtained from individual pads at -35 °C. At room temperature (25 °C) an average energy resolution of 380 eV FWHM is achieved and a resolution of 350 eV FWHM (41 rms electrons) is the best performance. A simple cooling system constituted of Peltier cells is sufficient to reduce the reverse currents of the pads and their related shot noise contribution, in order to achieve resolutions better than 300 eV FWHM which is adequate for the EXAFS applications.

  1. Requirements for the Silicon Tracking System of CBM at FAIR

    International Nuclear Information System (INIS)

    Heuser, Johann M.; Deveaux, M.; Muentz, C.; Stroth, J.

    2006-01-01

    The Compressed Baryonic Matter (CBM) experiment at the future Facility for Antiproton and Ion Research (FAIR) in Darmstadt will systematically study dense baryonic matter created in collisions of intense heavy-ion beams with nuclear targets. The research addresses current questions of strong-interaction physics as confinement in normal nuclear matter, chiral symmetry restoration in deconfined matter at high temperatures and densities, and the search for the critical end-point of the phase boundary. With beams of ions as heavy as Au and U, energies up to 45GeV/nucleon and intensities up to 10 12 ions per pulse, FAIR will enable CBM to probe the phase diagram of quantum chromo dynamics (QCD) in a region poorly known, while being complementary to current and future research programmes at RHIC and LHC. The CBM experiment is planned as a fixed-target spectrometer optimized for the detection of rare probes. Among these are open charm and low-mass vector mesons, important observables for the initial energetic and dense phase of the collisions. The experimental concept and challenge is to accomplish charged particle tracking in the high-multiplicity, high-radiation collision environment. This will be realized exclusively with a silicon tracking detector system installed in a strong magnetic dipole field directly behind the target. Key to the physics of CBM and benchmark for the tracking is the reconstruction of short-lived charmed mesons that puts high demands on the silicon detectors. The article presents a conceptual design of the CBM experiment with emphasis on the silicon tracking system. Requirements for silicon microstrip and pixel detectors and their arrangement in the tracker are discussed in relation to important physics observables addressed by CBM

  2. A Novel Silicon Micromachined Integrated MCM Thermal Management System

    Science.gov (United States)

    Kazmierczak, M. J.; Henderson, H. T.; Gerner, F. M.

    1997-01-01

    "Micromachining" is a chemical means of etching three-dimensional structures, typically in single- crystalline silicon. These techniques are leading toward what is coming to be referred to as MEMS (Micro Electro Mechanical Systems), where in addition to the ordinary two-dimensional (planar) microelectronics, it is possible to build three-dimensional n-ticromotors, electrically- actuated raicrovalves, hydraulic systems and much more on the same microchip. These techniques become possible because of differential etching rates of various crystallographic planes and materials used for semiconductor n-ticrofabfication. The University of Cincinnati group in collaboration with Karl Baker at NASA Lewis were the first to form micro heat pipes in silicon by the above techniques. Current work now in progress using MEMS technology is now directed towards the development of the next generation in MCM (Multi Chip Module) packaging. Here we propose to develop a complete electronic thermal management system which will allow densifica6on in chip stacking by perhaps two orders of magnitude. Furthermore the proposed technique will allow ordinary conu-nercial integrated chips to be utilized. Basically, the new technique involves etching square holes into a silicon substrate and then inserting and bonding commercially available integrated chips into these holes. For example, over a 100 1/4 in. by 1 /4 in. integrated chips can be placed on a 4 in. by 4 in. silicon substrate to form a Multi-Chip Module (MCM). Placing these MCM's in-line within an integrated rack then allows for three-diniensional stacking. Increased miniaturization of microelectronic circuits will lead to very high local heat fluxes. A high performance thermal management system will be specifically designed to remove the generated energy. More specifically, a compact heat exchanger with milli / microchannels will be developed and tested to remove the heat through the back side of this MCM assembly for moderate and high

  3. Endothelial progenitors encapsulated in bioartificial niches are insulated from systemic cytotoxicity and are angiogenesis competent.

    Science.gov (United States)

    Ratliff, B B; Ghaly, T; Brudnicki, P; Yasuda, K; Rajdev, M; Bank, M; Mares, J; Hatzopoulos, A K; Goligorsky, M S

    2010-07-01

    Intrinsic stem cells (SC) participate in tissue remodeling and regeneration in various diseases and following toxic insults. Failure of tissue regeneration is in part attributed to lack of SC protection from toxic stress of noxious stimuli, thus prompting intense research efforts to develop strategies for SC protection and functional preservation for in vivo delivery. One strategy is creation of artificial SC niches in an attempt to mimic the requirements of endogenous SC niches by generating scaffolds with properties of extracellular matrix. Here, we investigated the use of hyaluronic acid (HA) hydrogels as an artificial SC niche and examined regenerative capabilities of encapsulated embryonic endothelial progenitor cells (eEPC) in three different in vivo models. Hydrogel-encapsulated eEPC demonstrated improved resistance to toxic insult (adriamycin) in vitro, thus prompting in vivo studies. Implantation of HA hydrogels containing eEPC to mice with adriamycin nephropathy or renal ischemia resulted in eEPC mobilization to injured kidneys (and to a lesser extent to the spleen) and improvement of renal function, which was equal or superior to adoptively transferred EPC by intravenous infusion. In mice with hindlimb ischemia, EPC encapsulated in HA hydrogels dramatically accelerated the recovery of collateral circulation with the efficacy superior to intravenous infusion of EPC. In conclusion, HA hydrogels protect eEPC against adriamycin cytotoxicity and implantation of eEPC encapsulated in HA hydrogels supports renal regeneration in ischemic and cytotoxic (adriamycin) nephropathy and neovascularization of ischemic hindlimb, thus establishing their functional competence and superior capabilities to deliver stem cells stored in and released from this bioartificial niche.

  4. Systematic characterization and quality assurance of silicon micro-strip sensors for the Silicon Tracking System of the CBM experiment

    Science.gov (United States)

    Ghosh, P.

    2014-07-01

    The Silicon Tracking System (STS) is the central detector of the Compressed Baryonic Matter (CBM) experiment at future Facility for Anti-proton and Ion Research (FAIR) at Darmstadt. The task of the STS is to reconstruct trajectories of charged particles originating at relatively high multiplicities from the high rate beam-target interactions. The tracker comprises of 300 μm thick silicon double-sided micro-strip sensors. These sensors should be radiation hard in order to reconstruct charged particles up to a maximum radiation dose of 1 × 1014neqcm-2. Systematic characterization allows us to investigate the sensor response and perform quality assurance (QA) tests. In this paper, systematic characterization of prototype double-sided silicon micro-strip sensors will be discussed. This procedure includes visual, passive electrical, and radiation hardness test. Presented results include tests on three different prototypes of silicon micro-strip sensors.

  5. Systematic characterization and quality assurance of silicon micro-strip sensors for the Silicon Tracking System of the CBM experiment

    International Nuclear Information System (INIS)

    Ghosh, P

    2014-01-01

    The Silicon Tracking System (STS) is the central detector of the Compressed Baryonic Matter (CBM) experiment at future Facility for Anti-proton and Ion Research (FAIR) at Darmstadt. The task of the STS is to reconstruct trajectories of charged particles originating at relatively high multiplicities from the high rate beam-target interactions. The tracker comprises of 300 μm thick silicon double-sided micro-strip sensors. These sensors should be radiation hard in order to reconstruct charged particles up to a maximum radiation dose of 1 × 10 14 n eq cm −2 . Systematic characterization allows us to investigate the sensor response and perform quality assurance (QA) tests. In this paper, systematic characterization of prototype double-sided silicon micro-strip sensors will be discussed. This procedure includes visual, passive electrical, and radiation hardness test. Presented results include tests on three different prototypes of silicon micro-strip sensors

  6. Ultra-compact silicon nitride grating coupler for microscopy systems

    OpenAIRE

    Zhu, Yunpeng; Wang, Jie; Xie, Weiqiang; Tian, Bin; Li, Yanlu; Brainis, Edouard; Jiao, Yuqing; Van Thourhout, Dries

    2017-01-01

    Grating couplers have been widely used for coupling light between photonic chips and optical fibers. For various quantum-optics and bio-optics experiments, on the other hand, there is a need to achieve good light coupling between photonic chips and microscopy systems. Here, we propose an ultra-compact silicon nitride (SiN) grating coupler optimized for coupling light from a waveguide to a microscopy system. The grating coupler is about 4 by 2 mu m(2) in size and a 116 nm 1 dB bandwidth can be...

  7. Systematic irradiation studies and quality assurance of silicon strip sensors for the CBM Silicon Tracking System

    International Nuclear Information System (INIS)

    Larionov, Pavel

    2016-10-01

    The Compressed Baryonic Matter (CBM) experiment at the upcoming Facility for Antiproton and Ion Research (FAIR) is designed to investigate the phase diagram of strongly interacting matter at neutron star core densities under laboratory conditions. This work is a contribution to the development of the main tracking detector of the CBM experiment - the Silicon Tracking System (STS), designed to provide the tracking and the momentum information for charged particles in a high multiplicity environment. The STS will be composed of about 900 highly segmented double-sided silicon strip sensors and is expected to face a harsh radiation environment up to 1 x 10 14 cm -2 in 1 MeV neutron equivalent fluence after several years of operation. The two most limiting factors of the successful operation of the system are the radiation damage and the quality of produced silicon sensors. It is therefore of importance to ensure both the radiation tolerance of the STS sensors and their quality during the production phase. The first part of this work details the investigation of the radiation tolerance of the STS sensors. Series of irradiations of miniature sensors as well as full-size prototype sensors were performed with reactor neutrons and 23 MeV protons to a broad range of fluences, up to 2 x 10 14 n eq /cm 2 . The evolution of the main sensor characteristics (leakage current, full depletion voltage and charge collection) was extensively studied both as a function of accumulated fluence and time after irradiation. In particular, charge collection measurements of miniature sensors demonstrated the ability of the sensors to yield approx. 90% to 95% of the signal after irradiation up to the lifetime fluence, depending on the readout side. First results on the charge collection performance of irradiated full-size prototype sensors have been obtained, serving as an input data for further final signal-to-noise evaluation in the whole readout chain. Operational stability of these

  8. Systematic irradiation studies and quality assurance of silicon strip sensors for the CBM Silicon Tracking System

    Energy Technology Data Exchange (ETDEWEB)

    Larionov, Pavel

    2016-10-15

    The Compressed Baryonic Matter (CBM) experiment at the upcoming Facility for Antiproton and Ion Research (FAIR) is designed to investigate the phase diagram of strongly interacting matter at neutron star core densities under laboratory conditions. This work is a contribution to the development of the main tracking detector of the CBM experiment - the Silicon Tracking System (STS), designed to provide the tracking and the momentum information for charged particles in a high multiplicity environment. The STS will be composed of about 900 highly segmented double-sided silicon strip sensors and is expected to face a harsh radiation environment up to 1 x 10{sup 14} cm{sup -2} in 1 MeV neutron equivalent fluence after several years of operation. The two most limiting factors of the successful operation of the system are the radiation damage and the quality of produced silicon sensors. It is therefore of importance to ensure both the radiation tolerance of the STS sensors and their quality during the production phase. The first part of this work details the investigation of the radiation tolerance of the STS sensors. Series of irradiations of miniature sensors as well as full-size prototype sensors were performed with reactor neutrons and 23 MeV protons to a broad range of fluences, up to 2 x 10{sup 14} n{sub eq}/cm{sup 2}. The evolution of the main sensor characteristics (leakage current, full depletion voltage and charge collection) was extensively studied both as a function of accumulated fluence and time after irradiation. In particular, charge collection measurements of miniature sensors demonstrated the ability of the sensors to yield approx. 90% to 95% of the signal after irradiation up to the lifetime fluence, depending on the readout side. First results on the charge collection performance of irradiated full-size prototype sensors have been obtained, serving as an input data for further final signal-to-noise evaluation in the whole readout chain. Operational

  9. The silicon tracking system of the CBM experiment at FAIR

    Energy Technology Data Exchange (ETDEWEB)

    Singla, Minni [GSI Darmstadt (Germany); Collaboration: CBM-Collaboration

    2015-07-01

    The Compressed Baryonic Matter (CBM) experiment, one of the major scientific pillars at FAIR, will explore the phase diagram of strongly interacting matter at the highest net-baryon densities in nucleus-nucleus collisions with interaction rates up to 10 MHz. The Silicon Tracking System is the central detector system of the CBM experiment. Its task is to perform track reconstruction and momentum determination for all charged particles created in beam-target collisions at SIS 100 and SIS 300 beam energies. The technical challenges to meet are a high granularity matching the high track densities, a fast self-triggering read-out coping with high interaction rates, and a low mass to yield high momentum resolution of Δp/p=1%. The detector system acceptance covers polar angles between 2.5 and 25 degrees and will be operated in the 1 T field of a superconducting dipole magnet. We introduce the concept of the STS, being comprised of eight tracking stations employing ∝1300 double-sided silicon microstrip sensors on modular structures that keep the read-out electronics outside the physics aperture. Ultra-thin-multiline micro-cables will be used to bridge the distance between the microstrip sensors and the readout electronics. Infrastructure such as power lines and cooling plates will be placed at the periphery of the stations. The status of the STS development is summarized in the presentation, including an overview on sensors, read-out electronics, prototypes, and system integration.

  10. Silicon strip detector system for Fermilab E706

    Energy Technology Data Exchange (ETDEWEB)

    Engels, E Jr; Mani, S; Plants, D; Shepard, P F; Wilkins, R [Pittsburgh Univ., PA (USA); Hossain, S [Northeastern Univ., Boston, MA (USA)

    1984-09-15

    Fermilab Experiment E706 is an experiment to study direct photon production in hadron-hadron collisions at the Fermilab Tevatron II. A part of the charged particle spectrometer is a silicon strip detector system used to determine the position of interaction vertices in the production target and to provide angular formation about the secondary hadrons produced in a collision. We present some design criteria, as well as the results of tests of a wafer similar to those to be used in the experiment.

  11. VISION: a Versatile and Innovative SIlicOn tracking system

    CERN Document Server

    Lietti, Daniela; Vallazza, Erik

    This thesis work focuses on the study of the performance of different tracking and profilometry systems (the so-called INSULAB, INSUbria LABoratory, and VISION, Versatile and Innovative SIlicON, Telescopes) used in the last years by the NTA-HCCC, the COHERENT (COHERENT effects in crystals for the physics of accelerators), ICE-RAD (Interaction in Crystals for Emission of RADiation) and CHANEL (CHAnneling of NEgative Leptons) experiments, four collaborations of the INFN (Istituto Nazionale di Fisica Nucleare) dedicated to the research in the crystals physics field.

  12. Interface Control Document Between the Double-Shell Tank (DST) system and the Waste Encapsulation and Storage Facility (WESF)

    International Nuclear Information System (INIS)

    HOFFERBER, G.A.

    2000-01-01

    This Interface Control Document (ICD) describes interfaces between the Double-Shell Tanks (DST) System and Waste Encapsulation and Storage Facility (WESF) (figure 1). WESF is currently operational as a storage facility for cesium and strontium capsules. This ICD covers current operational interfaces and those envisioned during Terminal Clean Out (TCO) activities in the future. WESF and the DST System do not have a direct physical interface. The waste will be moved by tank trailer to the 204-AR waste unloading facility. The purpose of the ICD process is to formalize working agreements between the River Protection Project (RPP) DST System and systems/facilities operated by organizations or companies internal and external to RPP. This ICD has been developed as part of the requirements basis for design of the DST System to support the Phase I Privatization effort

  13. Alginate encapsulated mesoporous silica nanospheres as a sustained drug delivery system for the poorly water-soluble drug indomethacin

    Directory of Open Access Journals (Sweden)

    Liang Hu

    2014-08-01

    Full Text Available We applied a combination of inorganic mesoporous silica material, frequently used as drug carriers, and a natural organic polymer alginate (ALG, to establish a sustained drug delivery system for the poorly water-soluble drug Indomethacin (IND. Mesoporous silica nanospheres (MSNs were synthesized using an organic template method and then functionalized with aminopropyl groups through postsynthesis. After drug loading into the pores of aninopropyl functionalized MSNs (AP-MSNs, IND loaded AP-MSNs (IND-AP-MSNs were encapsulated by ALG through the ionic interaction. The effects of surface chemical groups and ALG layer on IND release were systematically studied using scanning electron microscopy (SEM, transmission electron microscopy (TEM, nitrogen adsorption, zeta-potential analysis and TGA analysis. The surface structure and surface charge changes of the ALG encapsulated AP-MSNs (ALG-AP-MSNs were also investigated. The results showed that sustained release of IND from the designed drug delivery system was mainly due to the blockage effect from the coated ALG. We believe that this combination will help designing oral sustained drug delivery systems for poorly water-soluble drugs.

  14. Multilayer encapsulated mesoporous silica nanospheres as an oral sustained drug delivery system for the poorly water-soluble drug felodipine

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Liang [Department of Pharmaceutics, Shenyang Pharmaceutical University, P.O. Box 32, Liaoning Province, Shenyang 110016 (China); Sun, Hongrui [English Teaching Department, School of Basic Courses, Shenyang Pharmaceutical University, Wenhua Road 103, Shenyang 110016 (China); Zhao, Qinfu; Han, Ning; Bai, Ling; Wang, Ying; Jiang, Tongying [Department of Pharmaceutics, Shenyang Pharmaceutical University, P.O. Box 32, Liaoning Province, Shenyang 110016 (China); Wang, Siling, E-mail: silingwang@syphu.edu.cn [Department of Pharmaceutics, Shenyang Pharmaceutical University, P.O. Box 32, Liaoning Province, Shenyang 110016 (China)

    2015-02-01

    We used a combination of mesoporous silica nanospheres (MSN) and layer-by-layer (LBL) self-assembly technology to establish a new oral sustained drug delivery system for the poorly water-soluble drug felodipine. Firstly, the model drug was loaded into MSN, and then the loaded MSN were repeatedly encapsulated by chitosan (CHI) and acacia (ACA) via LBL self-assembly method. The structural features of the samples were studied using scanning electron microscopy (SEM), transmission electron microscopy (TEM) and nitrogen adsorption. The encapsulating process was monitored by zeta-potential and surface tension measurements. The physical state of the drug in the samples was characterized by differential scanning calorimetry (DSC) and X-ray diffractometry (XRD). The influence of the multilayer with different number of layers on the drug release rate was studied using thermal gravimetric analysis (TGA) and surface tension measurement. The swelling effect and the structure changes of the multilayer were investigated to explore the relationship between the drug release behavior and the state of the multilayer under different pH conditions. The stability and mucosa adhesive ability of the prepared nanoparticles were also explored. After multilayer coating, the drug release rate was effectively controlled. The differences in drug release behavior under different pH conditions could be attributed to the different states of the multilayer. And the nanoparticles possessed good stability and strong mucosa adhesive ability. We believe that this combination offers a simple strategy for regulating the release rate of poorly water-soluble drugs and extends the pharmaceutical applications of inorganic materials and polymers. - Highlights: • A combination of inorganic and organic materials was applied. • Mesoporous silica nanospheres (MSN) were used as drug carriers. • Chitosan and acacia were encapsulated through layer-by-layer self-assembly. • The release rate of the poorly

  15. Multilayer encapsulated mesoporous silica nanospheres as an oral sustained drug delivery system for the poorly water-soluble drug felodipine

    International Nuclear Information System (INIS)

    Hu, Liang; Sun, Hongrui; Zhao, Qinfu; Han, Ning; Bai, Ling; Wang, Ying; Jiang, Tongying; Wang, Siling

    2015-01-01

    We used a combination of mesoporous silica nanospheres (MSN) and layer-by-layer (LBL) self-assembly technology to establish a new oral sustained drug delivery system for the poorly water-soluble drug felodipine. Firstly, the model drug was loaded into MSN, and then the loaded MSN were repeatedly encapsulated by chitosan (CHI) and acacia (ACA) via LBL self-assembly method. The structural features of the samples were studied using scanning electron microscopy (SEM), transmission electron microscopy (TEM) and nitrogen adsorption. The encapsulating process was monitored by zeta-potential and surface tension measurements. The physical state of the drug in the samples was characterized by differential scanning calorimetry (DSC) and X-ray diffractometry (XRD). The influence of the multilayer with different number of layers on the drug release rate was studied using thermal gravimetric analysis (TGA) and surface tension measurement. The swelling effect and the structure changes of the multilayer were investigated to explore the relationship between the drug release behavior and the state of the multilayer under different pH conditions. The stability and mucosa adhesive ability of the prepared nanoparticles were also explored. After multilayer coating, the drug release rate was effectively controlled. The differences in drug release behavior under different pH conditions could be attributed to the different states of the multilayer. And the nanoparticles possessed good stability and strong mucosa adhesive ability. We believe that this combination offers a simple strategy for regulating the release rate of poorly water-soluble drugs and extends the pharmaceutical applications of inorganic materials and polymers. - Highlights: • A combination of inorganic and organic materials was applied. • Mesoporous silica nanospheres (MSN) were used as drug carriers. • Chitosan and acacia were encapsulated through layer-by-layer self-assembly. • The release rate of the poorly

  16. A tracer aided study on silicon chemistry in biological systems

    NARCIS (Netherlands)

    Brasser, H.J.

    2009-01-01

    Silicon (Si) is omnipresent in nature, and it is involved in important but diverse roles in a broad range of organisms, including diatoms, higher plants and humans. Some organisms, like the diatoms, need high amounts of silicon, and master silicon chemistry to a high extend using several enzymes.

  17. The Silicon Tracking System of the CBM experiment at FAIR

    Directory of Open Access Journals (Sweden)

    Teklishyn Maksym

    2018-01-01

    Full Text Available The Silicon Tracking System (STS is the central detector in the Compressed Baryonic Matter (CBM experiment at FAIR. Operating in the 1Tm dipole magnetic field, the STS will enable pile-up free detection and momentum measurement of the charged particles originating from beam-target nuclear interactions at rates up to 10 MHz. The STS consists of 8 tracking stations based on double-sided silicon micro-strip sensors equipped with fast, self-triggering read-out electronics. With about two million read-out channels, the STS will deliver a high-rate stream of time-stamped data that is transferred to a computing farm for on-line event determination and analysis. The functional building block is a detector module consisting of a sensor, micro-cables and two front-end electronics boards. In this contribution, the development status of the STS components and the system integration is discussed and an outlook on the detector construction is given.

  18. The silicon tracking system of the CBM experiment

    Energy Technology Data Exchange (ETDEWEB)

    Balog, Tomas [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Darmstadt (Germany); Collaboration: CBM-Collaboration

    2014-07-01

    The Compressed Baryonic Matter (CBM) experiment at FAIR will explore the phase diagram of strongly interacting matter at the highest net-baryon densities in nucleus-nucleus collisions with interaction rates up to 10 MHz. As the core tracking detector of CBM the Silicon Tracking System (STS) will be installed in the gap of the 1 T super conducting dipole magnet for reconstruction of charged particle trajectories and its momenta. The requirement on momentum resolution, Δp/p=1%, can only be achieved with an ultra-low material budget, imposing particular restrictions on the location of 2.5 million channel front-end electronics dissipating 40 KW in the fiducial volume of about 2 m{sup 3}. The concept of the STS is based on a modular structure containing 300 μm thick double-sided silicon microstrip sensors read out through ultra-thin multi-line micro-cables with fast self-triggering electronics. As central building blocks the modules consisting of each a sensor, micro-cable and front-end electronics will be mounted with lightweight carbon fiber support structures onto 8 detector stations. At the station periphery infrastructure such as power and cooling lines will be placed. The status of the STS development is summarized in the presentation, including an overview on sensors, read-out electronics, prototypes, and system integration.

  19. Performance characteristics and radiation damage results from the Fermilab E706 silicon microstrip detector system

    Energy Technology Data Exchange (ETDEWEB)

    Engels, E Jr; Mani, S; Orris, D; Shepard, P F; Weerasundara, P D; Choudhary, B C; Joshi, U; Kapoor, V; Shivpuri, R; Baker, W

    1989-07-01

    A charged particle spectrometer containing a 7120-channel silicon microstrip detector system, one component of Fermilab experiment E706 to study direct photon production in hadron-hadron collisions, was utilized in a run in which 6 million events were recorded. We describe the silicon system, provide early results of track and vertex reconstruction, and present data on the radiation damage to the silicon wafers resulting from the narrow high intensity beam. (orig.).

  20. Systemic embolism produced by subcutaneous injections of liquid silicone for esthetic purposes

    International Nuclear Information System (INIS)

    Falconi, Guillermo

    2003-01-01

    Even though its use is not recommended, liquid silicone is a substance that has been used illegally for esthetic purposes for a long time. A case report is presented in which a young woman was injected subcutaneously, by an uncertified practitioner, industrial fluid silicone and subsequently developed a case of systemic embolism with pulmonary, skin and ocular complications. This article explains the physiopathology and the different manifestations of systemic embolism produced by fluid silicone. TAC was used. (The author)

  1. Enhanced polymeric encapsulation for MEMS based multi sensors for fisheries research

    DEFF Research Database (Denmark)

    Birkelund, Karen; Nørgaard, Lars; Thomsen, Erik Vilain

    2011-01-01

    light intensity, temperature, pressure and conductivity. For precise and fast measurements a direct exposure of the sensor to the water is desirable. A potted tube encapsulation concept has shown to be promising for accurate and fast measurements in harsh environment, provided a tight sealing......This paper presents the challenges of a packaged MEMS-based multi sensor system that allow for direct exposure of the sensing part to sea water. The system is part of a data storage tag used on fish to provide the researcher with information on fish behaviour and migration. The sensor measures...... compared to low pressure chemical vapor deposited (LPCVD) silicon nitride and untreated silicon dioxide....

  2. Evaluation of an oral carrier system in rats: bioavailability and gastrointestinal absorption properties of curcumin encapsulated PBCA nanoparticles

    International Nuclear Information System (INIS)

    Sun Min; Zhao Lixia; Guo Chenyu; Cao Fengliang; Chen Huanlei; Zhao Liyan; Tan Qi; Zhu Xiuqing; Zhu Fanping; Ding Tingting; Zhai Yingjie; Zhai Guangxi

    2012-01-01

    A new oral delivery system, polybutylcyanoacrylate nanoparticles (PBCNs), was introduced to improve the oral bioavailability of curcumin (CUR), a poorly soluble drug. The formulation was optimized by orthogonal design and the optimal PBCNs loading CUR exhibited a spherical shape under transmission electron microscopy with a range of 40–400 nm. Physicochemical state of CUR in PBCN was investigated by X-ray diffraction and the possible structure changes occurring in CUR after conjugating with polybutylcyanoacrylate were studied with FTIR. The results indicated that CUR in PBCN was in a non-crystalline state and CUR was encapsulated in PBCN without chemical reaction. The oral pharmacokinetic study was conducted in rats and the relative bioavailability of CUR encapsulated PBCNs to the crude CUR was more than 800%. The in situ absorption experiment in rat intestine indicated the absorption was first order with passive diffusion mechanism. The absorption results in various segments of intestine showed that the main absorption sites were ileum and colon. It can be concluded that PBCNs as an oral carrier can significantly improve the oral absorption of a poorly soluble drug.

  3. Evaluation of an oral carrier system in rats: bioavailability and gastrointestinal absorption properties of curcumin encapsulated PBCA nanoparticles

    Science.gov (United States)

    Sun, Min; Zhao, Lixia; Guo, Chenyu; Cao, Fengliang; Chen, Huanlei; Zhao, Liyan; Tan, Qi; Zhu, Xiuqing; Zhu, Fanping; Ding, Tingting; Zhai, Yingjie; Zhai, Guangxi

    2012-02-01

    A new oral delivery system, polybutylcyanoacrylate nanoparticles (PBCNs), was introduced to improve the oral bioavailability of curcumin (CUR), a poorly soluble drug. The formulation was optimized by orthogonal design and the optimal PBCNs loading CUR exhibited a spherical shape under transmission electron microscopy with a range of 40-400 nm. Physicochemical state of CUR in PBCN was investigated by X-ray diffraction and the possible structure changes occurring in CUR after conjugating with polybutylcyanoacrylate were studied with FTIR. The results indicated that CUR in PBCN was in a non-crystalline state and CUR was encapsulated in PBCN without chemical reaction. The oral pharmacokinetic study was conducted in rats and the relative bioavailability of CUR encapsulated PBCNs to the crude CUR was more than 800%. The in situ absorption experiment in rat intestine indicated the absorption was first order with passive diffusion mechanism. The absorption results in various segments of intestine showed that the main absorption sites were ileum and colon. It can be concluded that PBCNs as an oral carrier can significantly improve the oral absorption of a poorly soluble drug.

  4. Evaluation of an oral carrier system in rats: bioavailability and gastrointestinal absorption properties of curcumin encapsulated PBCA nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Sun Min; Zhao Lixia; Guo Chenyu; Cao Fengliang; Chen Huanlei; Zhao Liyan; Tan Qi; Zhu Xiuqing; Zhu Fanping; Ding Tingting; Zhai Yingjie; Zhai Guangxi, E-mail: professorzhai@yeah.net [Shandong University, Department of Pharmaceutics, College of Pharmacy (China)

    2012-02-15

    A new oral delivery system, polybutylcyanoacrylate nanoparticles (PBCNs), was introduced to improve the oral bioavailability of curcumin (CUR), a poorly soluble drug. The formulation was optimized by orthogonal design and the optimal PBCNs loading CUR exhibited a spherical shape under transmission electron microscopy with a range of 40-400 nm. Physicochemical state of CUR in PBCN was investigated by X-ray diffraction and the possible structure changes occurring in CUR after conjugating with polybutylcyanoacrylate were studied with FTIR. The results indicated that CUR in PBCN was in a non-crystalline state and CUR was encapsulated in PBCN without chemical reaction. The oral pharmacokinetic study was conducted in rats and the relative bioavailability of CUR encapsulated PBCNs to the crude CUR was more than 800%. The in situ absorption experiment in rat intestine indicated the absorption was first order with passive diffusion mechanism. The absorption results in various segments of intestine showed that the main absorption sites were ileum and colon. It can be concluded that PBCNs as an oral carrier can significantly improve the oral absorption of a poorly soluble drug.

  5. Development of an automatic characterisation system for silicon detectors

    CERN Document Server

    Hacker, J; Krammer, M; Wedenig, R

    2002-01-01

    The CMS experiment will be equipped with the largest silicon tracker in the world. The tracker will consist of about 25,000 silicon sensors which will cover an area of more than 200 m sup 2. Four quality test centres will carry out various checks on a representative sample of sensors to assure a homogeneous quality throughout the 2((1)/(2)) years of production. One of these centres is based in Vienna. To cope with the large number of sensors a fast and fully automatic characterisation system has been realised. We developed the software in LabView and built a cost-efficient probe station in house by assembling individual components and commercial instruments. Both the global properties of a sensor and the characteristic quantities of the individual strips can be measured. The measured data are immediately analysed and sent to a central database. The mechanical and electrical set-up will be explained and results from CMS prototype sensors are presented.

  6. The Laser Alignment System for the CMS silicon strip tracker

    CERN Document Server

    Olzem, Jan

    2009-01-01

    The Laser Alignment System (LAS) of the CMS silicon strip Tracker has been designed for surveying the geometry of the large-scale Tracker support structures. It uses 40 laser beams ($\\lambda$ = 1075 nm) that induce signals on a subset of the Tracker silicon sensors. The positions in space of the laser spots on the sensors are reconstructed with a resolution of 30 $\\mu$m. From this, the LAS is capable of permanent in-time monitoring of the different Tracker components relative to each other with better than 30 $\\mu$m precision. Additionally, it can provide an absolute measurement of the Tracker mechanical structure with an accuracy better than 70 $\\mu$m, thereby supplying additional input to the track based alignment at detector startup. 31 out of the 40 LAS beams have been successfully operated during the CMS cosmic muon data taking campaign in autumn 2008. The alignment of the Tracker Endcap Discs and of the discs with respect to the Tracker Inner Barrel and Tracker Outer Barrel subdetectors was measured w...

  7. LHCb Silicon Tracker DAQ and DCS Online Systems

    CERN Multimedia

    Buechler, A; Rodriguez, P

    2009-01-01

    The LHCb experiment at the Large Hadron Collider (LHC) at CERN in Geneva Switzerland is specialized on precision measurements of b quark decays. The Silicon Tracker (ST) contributes a crucial part in tracking the particle trajectories and consists of two silicon micro-strip detectors, the Tracker Turicensis upstream of the LHCb magnet and the Inner Tracker downstream. The radiation and the magnetic field represent new challenges for the implementation of a Detector Control System (DCS) and the data acquisition (DAQ). The DAQ has to deal with more than 270K analog readout channels, 2K readout chips and real time DAQ at a rate of 1.1 MHz with data processing at TELL1 level. The TELL1 real time algorithms for clustering thresholds and other computations run on dedicated FPGAs that implement 13K configurable parameters per board, in total 1.17 K parameters for the ST. After data processing the total throughput amounts to about 6.4 Gbytes from an input data rate of around ~337 Gbytes per second. A finite state ma...

  8. Development and Testing of the AMEGO Silicon Tracker System

    Science.gov (United States)

    Griffin, Sean; Amego Team

    2018-01-01

    The All-sky Medium Energy Gamma-ray Observatory (AMEGO) is a probe-class mission in consideration for the 2020 decadal review designed to operate at energies from ˜ 200 keV to > 10 GeV. Operating a detector in this energy regime is challenging due to the crossover in the interaction cross-section for Compton scattering and pair production. AMEGO is made of four major subsystems: a plastic anticoincidence detector for rejecting cosmic-ray events, a silicon tracker for measuring the energies of Compton scattered electrons and pair-production products, a CZT calorimeter for measuring the energy and location of Compton scattered photons, and a CsI calorimeter for measuring the energy of the pair-production products at high energies. The tracker comprises layers of dual-sided silicon strip detectors which provide energy and localization information for Compton scattering and pair-production events. A prototype tracker system is under development at GSFC; in this contribution we provide details on the verification, packaging, and testing of the prototype tracker, as well as present plans for the development of the front-end electronics, beam tests, and a balloon flight.

  9. Development of an automatic characterisation system for silicon detectors

    International Nuclear Information System (INIS)

    Hacker, J.; Bergauer, T.; Krammer, M.; Wedenig, R.

    2002-01-01

    The CMS experiment will be equipped with the largest silicon tracker in the world. The tracker will consist of about 25,000 silicon sensors which will cover an area of more than 200 m 2 . Four quality test centres will carry out various checks on a representative sample of sensors to assure a homogeneous quality throughout the 2((1)/(2)) years of production. One of these centres is based in Vienna. To cope with the large number of sensors a fast and fully automatic characterisation system has been realised. We developed the software in LabView and built a cost-efficient probe station in house by assembling individual components and commercial instruments. Both the global properties of a sensor and the characteristic quantities of the individual strips can be measured. The measured data are immediately analysed and sent to a central database. The mechanical and electrical set-up will be explained and results from CMS prototype sensors are presented

  10. A fast ADC system for silicon μstrips readout

    International Nuclear Information System (INIS)

    Inzani, P.; Pedrini, D.; Sala, S.

    1986-01-01

    A new fast ADC module has been designed. It is part of a large readout system for a high resolution vertex detector consisting of 12 silicon microstrip planes with more than 8000 channels. The module employs a set of monolithic gated integrators on input (LeCroy MIQ 401) multiplexed on a single 8 bit FADC (Thompson EFX8308). A built-in preprocessing, performed through look up tables, accomplishes equalization and reduction of the data and makes high level trigger feasible. As an additional feature, fast histogramming of all the channels in parallel has been made possible with an internal memory. Special care has been paid to realize a low cost and low power consumption system

  11. Carbon dioxide as a green carbon source for the synthesis of carbon cages encapsulating porous silicon as high performance lithium-ion battery anodes.

    Science.gov (United States)

    Zhang, Yaguang; Du, Ning; Chen, Yifan; Lin, Yangfan; Jiang, Jinwei; He, Yuanhong; Lei, Yu; Yang, Deren

    2018-03-28

    Si/C composite is one of the most promising candidate materials for next-generation lithium-ion battery anodes. Herein, we demonstrate the novel structure of carbon cages encapsulating porous Si synthesized by the reaction between magnesium silicide (Mg 2 Si) and carbon dioxide (CO 2 ) and subsequent acid washing. Benefitting from the in situ deposition through magnesiothermic reduction of CO 2 , the carbon cage seals the inner Si completely and shows higher graphitization than that obtained from the decomposition of acetylene. After removing MgO, pores are created, which can accommodate the volume change of the Si anode during the charge/discharge process. As the anode material for lithium-ion batteries, the porous Si/C electrode shows a charge capacity of ∼1124 mA h g -1 after 100 cycles with 86.4% capacity retention at the current density of 0.4 A g -1 . When the current density increases to 1.6 and 3.2 A g -1 , the capacity can still be maintained at ∼860 and ∼460 mA h g -1 , respectively. The prominent cycling and rate performance is contributed by the built-in space for Si expansion, static carbon cages that prevent penetration of electrolyte and stabilize the solid electrolyte interface (SEI) outside, and fast charge transport by the novel structure.

  12. Encapsulating spent nuclear fuel

    International Nuclear Information System (INIS)

    Fleischer, L.R.; Gunasekaran, M.

    1979-01-01

    A system is described for encapsulating spent nuclear fuel discharged from nuclear reactors in the form of rods or multi-rod assemblies. The rods are completely and contiguously enclosed in concrete in which metallic fibres are incorporated to increase thermal conductivity and polymers to decrease fluid permeability. This technique provides the advantage of acceptable long-term stability for storage over the conventional underwater storage method. Examples are given of suitable concrete compositions. (UK)

  13. Effects of ion implantation on charges in the silicon--silicon dioxide system

    International Nuclear Information System (INIS)

    Learn, A.J.; Hess, D.W.

    1977-01-01

    Structures consisting of thermally grown oxide on silicon were implanted with boron, arsenic, or argon ions. For argon implantation through oxides, an increased fixed oxide charge (Q/sub ss/) was observed with the increase being greater for than for silicon. This effect is attributed to oxygen recoil which produces additional excess ionized silicon in the oxide of a type similar to that arising in thermal oxidation. Fast surface state (N/sub st/) generation was also noted which in most cases obscured the Q/sub ss/ increase. Of various heat treatments tested, only a 900 degreeC anneal in hydrogen annihilated N/sub st/ and allowed Q/sub ss/ measurement. Such N/sub st/ apparently arises as a consequence of implantation damage at the silicon--silicon dioxide interface. With the exception of boron implantations into thick oxides or through aluminum electrodes, reduction of the mobile ionic charge (Q/sub o/) was achieved by implantation. The reduction again is presumably damage related and is not negated by high-temperature annealing but may be counterbalanced by aluminum incorporation in the oxide

  14. System software design for the CDF Silicon Vertex Detector

    Energy Technology Data Exchange (ETDEWEB)

    Tkaczyk, S. (Fermi National Accelerator Lab., Batavia, IL (United States)); Bailey, M. (Purdue Univ., Lafayette, IN (United States))

    1991-11-01

    An automated system for testing and performance evaluation of the CDF Silicon Vertex Detector (SVX) data acquisition electronics is described. The SVX data acquisition chain includes the Fastbus Sequencer and the Rabbit Crate Controller and Digitizers. The Sequencer is a programmable device for which we developed a high level assembly language. Diagnostic, calibration and data acquisition programs have been developed. A distributed software package was developed in order to operate the modules. The package includes programs written in assembly and Fortran languages that are executed concurrently on the SVX Sequencer modules and either a microvax or an SSP. Test software was included to assist technical personnel during the production and maintenance of the modules. Details of the design of different components of the package are reported.

  15. System software design for the CDF Silicon Vertex Detector

    International Nuclear Information System (INIS)

    Tkaczyk, S.; Bailey, M.

    1991-11-01

    An automated system for testing and performance evaluation of the CDF Silicon Vertex Detector (SVX) data acquisition electronics is described. The SVX data acquisition chain includes the Fastbus Sequencer and the Rabbit Crate Controller and Digitizers. The Sequencer is a programmable device for which we developed a high level assembly language. Diagnostic, calibration and data acquisition programs have been developed. A distributed software package was developed in order to operate the modules. The package includes programs written in assembly and Fortran languages that are executed concurrently on the SVX Sequencer modules and either a microvax or an SSP. Test software was included to assist technical personnel during the production and maintenance of the modules. Details of the design of different components of the package are reported

  16. Encapsulated microsensors for reservoir interrogation

    Science.gov (United States)

    Scott, Eddie Elmer; Aines, Roger D.; Spadaccini, Christopher M.

    2016-03-08

    In one general embodiment, a system includes at least one microsensor configured to detect one or more conditions of a fluidic medium of a reservoir; and a receptacle, wherein the receptacle encapsulates the at least one microsensor. In another general embodiment, a method include injecting the encapsulated at least one microsensor as recited above into a fluidic medium of a reservoir; and detecting one or more conditions of the fluidic medium of the reservoir.

  17. Durability of Polymeric Encapsulation Materials for a PMMA/glass Concentrator Photovoltaic System

    Energy Technology Data Exchange (ETDEWEB)

    Miller, David C.; Kempe, Michael D.; Muller, Matthew T; Gray, Matthew H.; Araki, Kenji; Kurtz, Sarah R.

    2014-04-08

    The durability of polymeric encapsulation materials was examined using outdoor exposure at the nominal geometric concentration of 500 suns. The results for 36 months cumulative field deployment are presented for materials including: poly(ethylene-co-vinyl acetate), (EVA); polyvinyl butyral (PVB); ionomer; polyethylene/ polyoctene copolymer (PO); thermoplastic polyurethane (TPU); poly(dimethylsiloxane) (PDMS); poly(diphenyl dimethyl siloxane) (PDPDMS); and poly(phenyl-methyl siloxane) (PPMS). Measurements of the field conditions including ambient temperature and ultraviolet (UV) dose were recorded at the test site during the experiment. Measurements for the experiment included optical transmittance (with subsequent analysis of solar-weighted transmittance, UV cut-off wavelength, and yellowness index), mass, visual photography, photoelastic imaging, and fluorescence spectroscopy. While the results to date for EVA are presented and discussed, examination here focuses more on the siloxane materials. A specimen recently observed to fail by thermal decomposition is discussed in terms of the implementation of the experiment as well as its fluorescence signature, which was observed to become more pronounced with age. Modulated thermogravimetry (allowing determination of the activation energy of thermal decomposition) was performed on a subset of the siloxanes to quantify the propensity for decomposition at elevated temperatures. Supplemental, Pt-catalyst- and primer-solutions as well as peroxide-cured PDMS specimens were examined to assess the source of the luminescence. The results of the study including the change in optical transmittance, observed failure modes, and subsequent analyses of the failure modes are described in the conclusions.

  18. Encapsulation of lead from hazardous CRT glass wastes using biopolymer cross-linked concrete systems

    International Nuclear Information System (INIS)

    Kim, Daeik; Quinlan, Michael; Yen, Teh Fu

    2009-01-01

    Discarded computer monitors and television sets are identified as hazardous materials due to the high content of lead in their cathode ray tubes (CRTs). Over 98% of lead is found in CRT glass. More than 75% of obsolete electronics including TV and CRT monitors are in storage because appropriate e-waste management and remediation technologies are insufficient. Already an e-waste tsunami is starting to roll across the US and the whole world. Thus, a new technology was developed as an alternative to current disposal methods; this method uses a concrete composite crosslinked with minute amounts of biopolymers and a crosslinking agent. Commercially available microbial biopolymers of xanthan gum and guar gum were used to encapsulate CRT wastes, reducing Pb leachability as measured by standard USEPA methods. In this investigation, the synergistic effect of the crosslinking reaction was observed through blending two different biopolymers or adding a crosslinking agent in biopolymer solution. This CRT-biopolymer-concrete (CBC) composite showed higher compressive strength than the standard concrete and a considerable decrease in lead leachability

  19. Silicon compilation: From the circuit to the system

    Science.gov (United States)

    Obrien, Keven

    The methodology used for the compilation of silicon from a behavioral level to a system level is presented. The aim was to link the heretofore unrelated areas of high level synthesis and system level design. This link will play an important role in the development of future design automation tools as it will allow hardware/software co-designs to be synthesized. A design methodology that alllows, through the use of an intermediate representation, SOLAR, a System level Design Language (SDL), to be combined with a Hardware Description Language (VHDL) is presented. Two main steps are required in order to transform this specification into a synthesizable one. Firstly, a system level synthesis step including partitioning and communication synthesis is required in order to split the model into a set of interconnected subsystems, each of which will be processed by a high level synthesis tool. For this latter step AMICAL is used and this allows powerful scheduling techniques to be used, that accept very abstract descriptions of control flow dominated circuits as input, and interconnected RTL blocks that may feed existing logic-level synthesis tools to be generated.

  20. STAR: The Secure Transportable Autonomous Reactor System - Encapsulated Fission Heat Source

    International Nuclear Information System (INIS)

    Ehud Greenspan

    2003-01-01

    OAK-B135 The Encapsulated Nuclear Heat Source (ENHS) is a novel 125 MWth fast spectrum reactor concept that was selected by the 1999 DOE NERI program as a candidate ''Generation-IV'' reactor. It uses Pb-Bi or other liquid-metal coolant and is intended to be factory manufactured in large numbers to be economically competitive. It is anticipated to be most useful to developing countries. The US team studying the feasibility of the ENHS reactor concept consisted of the University of California, Berkeley, Argonne National Laboratory (ANL), Lawrence Livermore National Laboratory (LLNL) and Westinghouse. Collaborating with the US team were three Korean organizations: Korean Atomic Energy Research Institute (KAERI), Korean Advanced Institute for Science and Technology (KAIST) and the University of Seoul, as well as the Central Research Institute of the Electrical Power Industry (CRIEPI) of Japan. Unique features of the ENHS include at least 20 years of operation without refueling; no fuel handling in the host country; no pumps and valves; excess reactivity does not exceed 1$; fully passive removal of the decay heat; very small probability of core damaging accidents; autonomous operation and capability of load-following over a wide range; very long plant life. In addition it offers a close match between demand and supply, large tolerance to human errors, is likely to get public acceptance via demonstration of superb safety, lack of need for offsite response, and very good proliferation resistance. The ENHS reactor is designed to meet the requirements of Generation IV reactors including sustainable energy supply, low waste, high level of proliferation resistance, high level of safety and reliability, acceptable risk to capital and, hopefully, also competitive busbar cost of electricity

  1. Liposomal Encapsulation for Systemic Delivery of Propranolol via Transdermal Iontophoresis Improves Bone Microarchitecture in Ovariectomized Rats.

    Science.gov (United States)

    Teong, Benjamin; Kuo, Shyh Ming; Tsai, Wei-Hsin; Ho, Mei-Ling; Chen, Chung-Hwan; Huang, Han Hsiang

    2017-04-13

    The stimulatory effects of liposomal propranolol (PRP) on proliferation and differentiation of human osteoblastic cells suggested that the prepared liposomes-encapsulated PRP exerts anabolic effects on bone in vivo. Iontophoresis provides merits such as sustained release of drugs and circumvention of first pass metabolism. This study further investigated and evaluated the anti-osteoporotic effects of liposomal PRP in ovariectomized (OVX) rats via iontophoresis. Rats subjected to OVX were administered with pure or liposomal PRP via iontophoresis or subcutaneous injection twice a week for 12 weeks. Changes in the microarchitecture at the proximal tibia and the fourth lumbar spine were assessed between pure or liposomal PRP treated and non-treated groups using micro-computed tomography. Administration of liposomal PRP at low dose (0.05 mg/kg) via iontophoresis over 2-fold elevated ratio between bone volume and total tissue volume (BV/TV) in proximal tibia to 9.0% whereas treatment with liposomal PRP at low and high (0.5 mg/kg) doses via subcutaneous injection resulted in smaller increases in BV/TV. Significant improvement of BV/TV and bone mineral density (BMD) was also found in the fourth lumbar spine when low-dose liposomal PRP was iontophoretically administered. Iontophoretic low-dose liposomal PRP also elevated trabecular numbers in tibia and trabecular thickness in spine. Enhancement of bone microarchitecture volumes has highlighted that liposomal formulation with transdermal iontophoresis is promising for PRP treatment at the lower dose and with longer duration than its clinical therapeutic range and duration to exhibit optimal effects against bone loss in vivo.

  2. The Silicon Tracking System of the CBM Experiment at FAIR

    Science.gov (United States)

    Heuser, Johann M.

    The Compressed Baryonic Matter (CBM) experiment at FAIR will conduct a systematic research program to explore the phase diagram of strongly interacting matter at highest net baryon densities and moderate temperatures. These conditions are to be created in collisions of heavy-ion beams with nuclear targets in the projectile beam energy range of 2 to 45 GeV/nucleon, initially coming from the SIS 100 synchrotron (up to 14 GeV/nucleon) and in a next step from SIS 300 enabling studies at the highest net baryon densities. Collision rates up to 107 per second are required to produce very rare probes with unprecedented statistics in this energy range. Their signatures are complex. These conditions call for detector systems designed to meet the extreme requirements in terms of rate capability, momentum and spatial resolution, and a novel data acquisition and trigger concept which is not limited by latency but by throughput. In the paper we describe the concept and development status of CBM's central detector, the Silicon Tracking System (STS). The detector realizes a large, highly granular and redundant detector system with fast read-out, and lays specific emphasis on low material budget in its physics aperture to achieve for charged particle tracks a momentum resolution of δp/p ≈ 1% at p > 1 GeV/c, at >95% track reconstruction efficiency. The detector employs 1220 highly segmented double-sided silicon micro-strip sensors of 300 µm thickness, mounted into 896 modular structures of various types that are aggregated on 106 low-mass carbon fiber ladders of different sizes that build up the tracking stations. The read-out electronics with its supply and cooling infrastructure is arranged at the periphery of the ladders, and provides a total channel count of 1.8 million. The signal transmission from the silicon sensors to the electronics is realized through ultra-thin multi-line aluminum-polyimide cables of up to half a meter length. The electronics generates a free

  3. The silicon tracking system of the CBM experiment at FAIR

    International Nuclear Information System (INIS)

    Heuser, Johann M.

    2015-01-01

    The Compressed Baryonic Matter (CBM) experiment at FAIR will conduct a systematic research program to explore the phase diagram of strongly interacting matter at highest net baryon densities and moderate temperatures. These conditions are to be created in collisions of heavy-ion beams with nuclear targets in the projectile beam energy range of 2 to 45 GeV/nucleon, initially coming from the SIS 100 synchrotron (up to 14 GeV/nucleon) and in a next step from SIS 300 enabling studies at the highest net baryon densities. Collision rates up to 10"7 per second are required to produce very rare probes with unprecedented statistics in this energy range. Their signatures are complex. These conditions call for detector systems designed to meet the extreme requirements in terms of rate capability, momentum and spatial resolution, and a novel data acquisition and trigger concept which is not limited by latency but by throughput. In the paper we describe the concept and development status of CBM's central detector, the Silicon Tracking System (STS). The detector realizes a large, highly granular and redundant detector system with fast read-out, and lays specific emphasis on low material budget in its physics aperture to achieve for charged particle tracks a momentum resolution of δp/p≈1% at p > 1 GeV/c, at >95% track reconstruction efficiency. The detector employs 1220 highly segmented double-sided silicon micro-strip sensors of 300 μm thickness, mounted into 896 modular structures of various types that are aggregated on 106 low-mass carbon fiber ladders of different sizes that build up the tracking stations. The read-out electronics with its supply and cooling infrastructure is arranged at the periphery of the ladders, and provides a total channel count of 1.8 million. The signal transmission from the silicon sensors to the electronics is realized through ultra-thin multi-line aluminum-polyimide cables of up to half a meter length. The electronics generates a free

  4. Quality assurance of double-sided silicon microstrip sensors for the silicon tracking system in the CBM experiment at FAIR

    Energy Technology Data Exchange (ETDEWEB)

    Larionov, Pavel [Goethe Universitaet, Frankfurt (Germany); Collaboration: CBM-Collaboration

    2015-07-01

    The Silicon Tracking System (STS) is the core tracking detector of the CBM experiment at FAIR. The system's task is to reconstruct the trajectories of the charged particles produced in the beam-target interactions, provide their momentum determination, and enable the detection of decay topologies. The STS will comprise 1220 double-sided silicon microstrip sensors. After production each sensor will go through a number of Quality Assurance procedures to verify their validity for performance in the STS and also to confirm the manufacturer's data. In this talk, results of the quality assurance procedures that are being applied to the latest STS prototype sensors, including detailed tests of the quality of each single strip, long-term stability and preparations for volume tests during series production, are presented.

  5. Characterization of a dose verification system dedicated to radiotherapy treatments based on a silicon detector multi-strips

    International Nuclear Information System (INIS)

    Bocca, A.; Cortes Giraldo, M. A.; Gallardo, M. I.; Espino, J. M.; Aranas, R.; Abou Haidar, Z.; Alvarez, M. A. G.; Quesada, J. M.; Vega-Leal, A. P.; Perez Neto, F. J.

    2011-01-01

    In this paper, we present the characterization of a silicon detector multi-strips (SSSSD: Single Sided Silicon Strip Detector), developed by the company Micron Semiconductors Ltd. for use as a verification system for radiotherapy treatments.

  6. POLYETHYLENE ENCAPSULATION

    International Nuclear Information System (INIS)

    Kalb, P.

    2001-01-01

    Polyethylene microencapsulation physically homogenizes and incorporates mixed waste particles within a molten polymer matrix, forming a solidified final waste form upon cooling. Each individual particle of waste is embedded within the polymer block and is surrounded by a durable, leach-resistant coating. The process has been successfully applied for the treatment of a broad range of mixed wastes, including evaporator concentrate salts, soil, sludges, incinerator ash, off-gas blowdown solutions, decontamination solutions, molten salt oxidation process residuals, ion exchange resins, granular activated carbon, shredded dry active waste, spill clean-up residuals, depleted uranium powders, and failed grout waste forms. For waste streams containing high concentrations of soluble toxic metal contaminants, additives can be used to further reduce leachability, thus improving waste loadings while meeting or exceeding regulatory disposal criteria. In this configuration, contaminants are both chemically stabilized and physically solidified, making the process a true stabilization/solidification (S/S) technology. Unlike conventional hydraulic cement grouts or thermosetting polymers, thermoplastic polymers such as polyethylene require no chemical. reaction for solidification. Thus, a stable, solid, final waste form product is assured on cooling. Variations in waste chemistry over time do not affect processing parameters and do not require reformulation of the recipe. Incorporation of waste particles within the polymer matrix serves as an aggregate and improves the mechanical strength and integrity of the waste form. The compressive strength of polyethylene microencapsulated waste forms varies based on the type and quantity of waste encapsulated, but is typically between 7 and 17.2 MPa (1000 and 2500 psi), well above the minimum strength of 0.4 MPa (160 psi) recommended by the U.S. Nuclear Regulatory Commission (NRC) for low-level radioactive waste forms in support of 10 CFR 61

  7. The Silicon Valley Eco System. High-energetic in many ways; Het Silicon Valley Eco Systeem: hoogenergetisch in vele opzichten

    Energy Technology Data Exchange (ETDEWEB)

    Van den Heuvel, J.

    2012-04-15

    The highly commended Silicon Valley Eco System is bubbling with energy with regard to the subjects that are focused upon, including sustainable energy, or the widely available expertise that is needed for the developments, good ideas, capital and optimism, fed by frequent examples of extraordinarily successful companies. The sheer endlessness of network opportunities joins all these elements frequently. This article addresses several noteworthy interactions in the field of sustainable energy over the last period. [Dutch] Het veel geroemde Silicon Valley eco systeem bruist van energie in de vorm van de onderwerpen waar men zich op richt, waaronder duurzame energie, of de ruim aanwezige expertise die nodig is voor de ontwikkelingen, goede ideeen, kapitaal, en optimisme, gevoed door regelmatige voorbeelden van buitensporig succesvolle bedrijven. De schier oneindige netwerkmogelijkheden brengen al deze elementen met grote regelmaat bij elkaar. In dit artikel volgen enkele vermeldenswaardige interacties op het vlak van duurzame energie uit de afgelopen periode.

  8. The development of two ASIC's for a fast silicon strip detector readout system

    International Nuclear Information System (INIS)

    Christain, D.; Haldeman, M.; Yarema, R.; Zimmerman, T.; Newcomer, F.M.; VanBerg, R.

    1989-01-01

    A high speed, low noise readout system for silicon strip detectors is being developed for Fermilab E771, which will begin taking data in 1989. E771 is a fixed target experiment designed to study the production of B hadrons by an 800 GeV/c proton beam. The experimental apparatus consists of an open geometry magnetic spectrometer featuring good muon and electron identification and a 16000 channel silicon microstrip vertex detector. This paper reviews the design and prototyping of two application specific integrated circuits (ASIC's) an amplifier and a discriminator, which are being produced for the silicon strip detector readout system

  9. Different encapsulation strategies for implanted electronics

    Directory of Open Access Journals (Sweden)

    Winkler Sebastian

    2017-09-01

    Full Text Available Recent advancements in implant technology include increasing application of electronic systems in the human body. Hermetic encapsulation of electronic components is necessary, specific implant functions and body environments must be considered. Additional functions such as wireless communication systems require specialized technical solutions for the encapsulation.

  10. Encapsulation of radioactive waste

    International Nuclear Information System (INIS)

    Pordes, O.; Plows, J.P.

    1980-01-01

    A method is described for encapsulating a particular radioactive waste which consists of suspending the waste in a viscous liquid encapsulating material, of synthetic resin monomers or prepolymers, and setting the encapsulating material by addition or condensation polymerization to form a solid material in which the waste is dispersed. (author)

  11. TGF-β3 encapsulated PLCL scaffold by a supercritical CO2-HFIP co-solvent system for cartilage tissue engineering.

    Science.gov (United States)

    Kim, Su Hee; Kim, Soo Hyun; Jung, Youngmee

    2015-05-28

    Mimicking the native tissue microenvironment is critical for effective tissue regeneration. Mechanical cues and sustained biological cues are important factors, particularly in load-bearing tissues such as articular cartilage or bone. Carriers including hydrogels and nanoparticles have been investigated to achieve sustained release of protein drugs. However, it is difficult to apply such carriers alone as scaffolds for cartilage regeneration because of their weak mechanical properties, and they must be combined with other biomaterials that have adequate mechanical strength. In this study, we developed the multifunctional scaffold which has similar mechanical properties to those of native cartilage and encapsulates TGF-β3 for chondrogenesis. In our previous work, we confirmed that poly(lactide-co-caprolacton) (PLCL) did not foam when exposed to supercritical CO2 below 45°C. Here, we used a supercritical carbon dioxide (scCO2)-1,1,1,3,3,3-hexafluoro-2-propanol (HFIP) co-solvent system to facilitate processing under mild conditions because high temperature causes protein denaturation and decreases bioactivity of the protein. This processing made it possible to fabricate a TGF-β3 encapsulated elastic porous PLCL scaffold at 37°C. We investigated the tissue regeneration efficiency of the TGF-β3 encapsulated PLCL scaffold using human adipose-derived stem cells (ADSCs) in vitro and in vivo (Groups; i. PLCL scaffold+Fibrin gel+TGF-β3, ii. TGF-β3 encapsulated PLCL scaffold+Fibrin gel, iii. TGF-β3 encapsulated PLCL scaffold). We evaluated the chondrogenic abilities of the scaffolds at 4, 8, and 12weeks after subcutaneous implantation of the constructs in immune-deficient mice. Based on TGF-β3 release studies, we confirmed that TGF-β3 molecules were released by 8weeks and remained in the PLCL matrix. Explants of TGF-β3 encapsulated scaffolds by a co-solvent system exhibited distinct improvement in the compressive E-modulus and deposition of extracellular matrix

  12. Silicon technology-based micro-systems for atomic force microscopy/photon scanning tunnelling microscopy.

    Science.gov (United States)

    Gall-Borrut, P; Belier, B; Falgayrettes, P; Castagne, M; Bergaud, C; Temple-Boyer, P

    2001-04-01

    We developed silicon nitride cantilevers integrating a probe tip and a wave guide that is prolonged on the silicon holder with one or two guides. A micro-system is bonded to a photodetector. The resulting hybrid system enables us to obtain simultaneously topographic and optical near-field images. Examples of images obtained on a longitudinal cross-section of an optical fibre are shown.

  13. Thermal system design and modeling of meniscus controlled silicon growth process for solar applications

    Science.gov (United States)

    Wang, Chenlei

    The direct conversion of solar radiation to electricity by photovoltaics has a number of significant advantages as an electricity generator. That is, solar photovoltaic conversion systems tap an inexhaustible resource which is free of charge and available anywhere in the world. Roofing tile photovoltaic generation, for example, saves excess thermal heat and preserves the local heat balance. This means that a considerable reduction of thermal pollution in densely populated city areas can be attained. A semiconductor can only convert photons with the energy of the band gap with good efficiency. It is known that silicon is not at the maximum efficiency but relatively close to it. There are several main parts for the photovoltaic materials, which include, single- and poly-crystalline silicon, ribbon silicon, crystalline thin-film silicon, amorphous silicon, copper indium diselenide and related compounds, cadmium telluride, et al. In this dissertation, we focus on melt growth of the single- and poly-crystalline silicon manufactured by Czochralski (Cz) crystal growth process, and ribbon silicon produced by the edge-defined film-fed growth (EFG) process. These two methods are the most commonly used techniques for growing photovoltaic semiconductors. For each crystal growth process, we introduce the growth mechanism, growth system design, general application, and progress in the numerical simulation. Simulation results are shown for both Czochralski and EFG systems including temperature distribution of the growth system, velocity field inside the silicon melt and electromagnetic field for the EFG growth system. Magnetic field is applied on Cz system to reduce the melt convection inside crucible and this has been simulated in our numerical model. Parametric studies are performed through numerical and analytical models to investigate the relationship between heater power levels and solidification interface movement and shape. An inverse problem control scheme is developed to

  14. Dental mesenchymal stem cells encapsulated in an alginate hydrogel co-delivery microencapsulation system for cartilage regeneration.

    Science.gov (United States)

    Moshaverinia, Alireza; Xu, Xingtian; Chen, Chider; Akiyama, Kentaro; Snead, Malcolm L; Shi, Songtao

    2013-12-01

    Dental-derived mesenchymal stem cells (MSCs) are promising candidates for cartilage regeneration, with a high capacity for chondrogenic differentiation. This property helps make dental MSCs an advantageous therapeutic option compared to current treatment modalities. The MSC delivery vehicle is the principal determinant for the success of MSC-mediated cartilage regeneration therapies. The objectives of this study were to: (1) develop a novel co-delivery system based on TGF-β1 loaded RGD-coupled alginate microspheres encapsulating periodontal ligament stem cells (PDLSCs) or gingival mesenchymal stem cells (GMSCs); and (2) investigate dental MSC viability and chondrogenic differentiation in alginate microspheres. The results revealed the sustained release of TGF-β1 from the alginate microspheres. After 4 weeks of chondrogenic differentiation in vitro, PDLSCs and GMSCs as well as human bone marrow mesenchymal stem cells (hBMMSCs) (as positive control) revealed chondrogenic gene expression markers (Col II and Sox-9) via qPCR, as well as matrix positively stained by Toluidine Blue and Safranin-O. In animal studies, ectopic cartilage tissue regeneration was observed inside and around the transplanted microspheres, confirmed by histochemical and immunofluorescent staining. Interestingly, PDLSCs showed more chondrogenesis than GMSCs and hBMMSCs (palginate microencapsulating dental MSCs make a promising candidate for cartilage regeneration. Our results highlight the vital role played by the microenvironment, as well as value of presenting inductive signals for viability and differentiation of MSCs. Copyright © 2013 Acta Materialia Inc. All rights reserved.

  15. Solar breeder: Energy payback time for silicon photovoltaic systems

    Science.gov (United States)

    Lindmayer, J.

    1977-01-01

    The energy expenditures of the prevailing manufacturing technology of terrestrial photovoltaic cells and panels were evaluated, including silicon reduction, silicon refinement, crystal growth, cell processing and panel building. Energy expenditures include direct energy, indirect energy, and energy in the form of equipment and overhead expenses. Payback times were development using a conventional solar cell as a test vehicle which allows for the comparison of its energy generating capability with the energies expended during the production process. It was found that the energy payback time for a typical solar panel produced by the prevailing technology is 6.4 years. Furthermore, this value drops to 3.8 years under more favorable conditions. Moreover, since the major energy use reductions in terrestrial manufacturing have occurred in cell processing, this payback time directly illustrates the areas where major future energy reductions can be made -- silicon refinement, crystal growth, and panel building.

  16. Encapsulated Islet Transplantation: Where Do We Stand?

    Science.gov (United States)

    Vaithilingam, Vijayaganapathy; Bal, Sumeet; Tuch, Bernard E

    2017-01-01

    Transplantation of pancreatic islets encapsulated within immuno-protective microcapsules is a strategy that has the potential to overcome graft rejection without the need for toxic immunosuppressive medication. However, despite promising preclinical studies, clinical trials using encapsulated islets have lacked long-term efficacy, and although generally considered clinically safe, have not been encouraging overall. One of the major factors limiting the long-term function of encapsulated islets is the host's immunological reaction to the transplanted graft which is often manifested as pericapsular fibrotic overgrowth (PFO). PFO forms a barrier on the capsule surface that prevents the ingress of oxygen and nutrients leading to islet cell starvation, hypoxia and death. The mechanism of PFO formation is still not elucidated fully and studies using a pig model have tried to understand the host immune response to empty alginate microcapsules. In this review, the varied strategies to overcome or reduce PFO are discussed, including alginate purification, altering microcapsule geometry, modifying alginate chemical composition, co-encapsulation with immunomodulatory cells, administration of pharmacological agents, and alternative transplantation sites. Nanoencapsulation technologies, such as conformal and layer-by-layer coating technologies, as well as nanofiber, thin-film nanoporous devices, and silicone based NanoGland devices are also addressed. Finally, this review outlines recent progress in imaging technologies to track encapsulated cells, as well as promising perspectives concerning the production of insulin-producing cells from stem cells for encapsulation.

  17. Encapsulated Curcumin for Transdermal Administration

    African Journals Online (AJOL)

    Purpose: To develop a proniosomal carrier system of curcumin for transdermal delivery. Methods: Proniosomes of curcumin were prepared by encapsulation of the drug in a mixture of Span 80, cholesterol and diethyl ether by ether injection method, and then investigated as a transdermal drug delivery system (TDDS).

  18. Effects of an Encapsulated Fruit and Vegetable Juice Concentrate on Obesity-Induced Systemic Inflammation: A Randomised Controlled Trial

    Directory of Open Access Journals (Sweden)

    Evan J. Williams

    2017-02-01

    Full Text Available Phytochemicals from fruit and vegetables reduce systemic inflammation. This study examined the effects of an encapsulated fruit and vegetable (F&V juice concentrate on systemic inflammation and other risk factors for chronic disease in overweight and obese adults. A double-blinded, parallel, randomized placebo-controlled trial was conducted in 56 adults aged ≥40 years with a body mass index (BMI ≥28 kg/m2. Before and after eight weeks daily treatment with six capsules of F&V juice concentrate or placebo, peripheral blood gene expression (microarray, quantitative polymerase chain reaction (qPCR, plasma tumour necrosis factor (TNFα (enzyme-linked immunosorbent assay (ELISA, body composition (Dual-energy X-ray absorptiometry (DEXA and lipid profiles were assessed. Following consumption of juice concentrate, total cholesterol, low-density lipoprotein (LDL cholesterol and plasma TNFα decreased and total lean mass increased, while there was no change in the placebo group. In subjects with high systemic inflammation at baseline (serum C-reactive protein (CRP ≥3.0 mg/mL who were supplemented with the F&V juice concentrate (n = 16, these effects were greater, with decreased total cholesterol, LDL cholesterol and plasma TNFα and increased total lean mass; plasma CRP was unchanged by the F&V juice concentrate following both analyses. The expression of several genes involved in lipogenesis, the nuclear factor-κB (NF-κB and 5′ adenosine monophosphate-activated protein kinase (AMPK signalling pathways was altered, including phosphomevalonate kinase (PMVK, zinc finger AN1-type containing 5 (ZFAND5 and calcium binding protein 39 (CAB39, respectively. Therefore, F&V juice concentrate improves the metabolic profile, by reducing systemic inflammation and blood lipid profiles and, thus, may be useful in reducing the risk of obesity-induced chronic disease.

  19. A Silicon d-spacing Mapping Measurement System With Resolution of 10-9

    International Nuclear Information System (INIS)

    Zhang Xiaowei; Sugiyama, Hiroshi; Fugimoto, Hiroyuki; Waseda, Atsushi; Takatomi, Toshikazu

    2010-01-01

    For determination of the Avogadro's number, a self-referenced lattice comparator established at the Photon Factory to deal with a d-spacing mapping measurement over the cross section of a 4 ∼ 5 inches FZ silicon rod. For uncertainty of 1x10 -8 of the unit cell volume, it is necessary to measure lattice parameter of silicon with resolution of 3x10 -9 at least. In this paper, we report the principle of our lattice comparator, characterize our measurement system, and show some mapping measurement results of FZ silicon with resolution of 3x10 -9 .

  20. Silicon Detector System for High Rate EXAFS Applications

    OpenAIRE

    Pullia, A.; Kraner, H. W.; Siddons, D. P.; Furenlid, L. R.; Bertuccio, G.

    1995-01-01

    A multichannel silicon pad detector for EXAFS (Extended X-ray Absorption Fine Structure) applications has been designed and built. The X-ray spectroscopic measurements demonstrate that an adequate energy resolution of 230 eV FWHM (corresponding to 27 rms electrons in silicon) can be achieved reliably at −35 °C. A resolution of 190 eV FWHM (corresponding to 22 rms electrons) has been obtained from individual pads at −35 °C. At room temperature (25 °C) an average energy resolution of 380 eV FWH...

  1. Development of an automation system for Iodine-125 brachytherapy seed encapsulated by Nd:YAG laser welding

    International Nuclear Information System (INIS)

    Somessari, S.L.; Feher, A.; Sprenger, F.E.; Rostelato, M.E.C.M.; Costa, F.E. da; Calvo, W.A.P.

    2011-01-01

    The aim of this work is to develop an automation system for iodine-125 radioactive seed production by Nd:YAG laser welding, which has been used successfully in low dose rate (LDR) brachytherapy treatment. This small seed consists of a welded titanium capsule, with 0.8 mm in diameter and 4.5 mm in length, containing iodine-125 adsorbed onto a silver rod. The iodine-125 seeds are implanted into the human prostate to irradiate the tumor for cancer treatment. Nowadays, the Radiation Technology Center, at Institute for Nuclear and Energy Research, Sao Paulo, Brazil (IPEN-CNEN/SP) imports and distributes 36,000 iodine-125 seeds per year, for the clinics and hospitals in the country. However, the Brazilian market potential is now over 8,000 iodine-125 seeds per month. The local production of these iodine-125 radioactive sources became a priority for the Institute, in order to reduce the price and the problems of prostate cancer management. It will permit to spread their use to a larger number of patients in Brazil. On the other hand, the industrial automation plays an important role for iodine-125 seeds in order to increase the productivity, with high quality and assurance, avoiding human factors, implementing and operating with good manufacturing practices (GMP). The technology consists of appliance electronic and electro-mechanical parts and components to control machines and processes. The automation system technology for iodine-125 seed production developed in this work was mainly assembled employing a programmable logic controller (PLC), a stepper motor, an Nd:YAG laser welding machine and a supervisory. The statistical repeatability of correctly encapsulated sealed sources with this automation system is greater than 95%. (authors)

  2. Wedge silicon detectors for the inner trackering system of CMS

    International Nuclear Information System (INIS)

    Catacchini, E.; Civinini, C.; D'Alessandro, R.; Focardi, E.; Meschini, M.; Parrini, G.; Pieri, M.; Wheadon, R.

    1997-01-01

    One ''wedge'' double sided silicon detector prototype for the CMS forward inner tracker has been tested both in laboratory and on a high energy particle beam. The results obtained indicate the most reliable solutions for the strip geometry of the junction side. Three different designs of ''wedge'' double sided detectors with different solutions for the ohmic side strip geometry are presented. (orig.)

  3. Monosilicide-disilicide-silicon phase equilibria in the nickel-platinum-silicon and nickel-palladium-silicon systems

    Science.gov (United States)

    Loomans, M. E.; Chi, D. Z.; Chua, S. J.

    2004-10-01

    Bulk-phase equilibria in Ni-rich/Si-rich alloys of the Ni-Pt-Si and Ni-Pd-Si systems were investigated. Results suggest that a bulk monosilicide solid solution, containing up to at least 11 at. pct Pt, exists in the Ni-Pt-Si system. Monosilicides containing more than 11 at. pct Pt were not examined. Results from both ternary systems point convincingly to the existence of a NiSi+Si↔NiSi2 eutectoid reaction near 700 °C in the Ni-Si binary system; data from the Ni-Pt-Si system, which yield the more accurate determination of the eutectoid temperature, place it at roughly 710 °C. The Pt and Pd concentrations of monosilicide in equilibrium with disilicide and Si were measured using energy-dispersive spectrometry (EDS) and were found to increase with temperature.

  4. A prototype silicon detector system for space cosmic-ray charge measurement

    Science.gov (United States)

    Zhang, Fei; Fan, Rui-Rui; Peng, Wen-Xi; Dong, Yi-Fa; Gong, Ke; Liang, Xiao-Hua; Liu, Ya-Qing; Wang, Huan-Yu

    2014-06-01

    A readout electronics system used for space cosmic-ray charge measurement for multi-channel silicon detectors is introduced in this paper, including performance measurements. A 64-channel charge sensitive ASIC (VA140) from the IDEAS company is used. With its features of low power consumption, low noise, large dynamic range, and high integration, it can be used in future particle detecting experiments based on silicon detectors.

  5. Ideality and Tunneling Level Systems (TLS) in amorphous silicon films.

    Science.gov (United States)

    Hellman, Frances

    Heat capacity, sound velocity, and internal friction of covalently bonded amorphous silicon (a-Si) films with and without hydrogen show that low energy excitations commonly called tunneling or two level systems (TLS) can be tuned over nearly 3 decades, from below detectable limits to the range commonly seen in glassy systems. This tuning is accomplished by growth temperature, thickness, growth rate, light soaking or annealing. We see a strong correlation with atomic density in a-Si and in literature analysis of other glasses, as well as with dangling bond density, sound velocity, and bond angle distribution as measured by Raman spectroscopy, but TLS density varies by orders of magnitude while these other measures of disorder vary by less than a factor of two. The lowest TLS films are grown at temperatures near 0.8 of the theoretical glass transition temperature of Si, similar to work on polymer films and suggestive that the high surface mobility at relatively low temperature of vapor deposition can produce materials close to an ideal glass, with higher density, lower energy, and low TLS due to fewer nearby configurations with similarly low energy. The TLS measured by heat capacity and internal friction are strongly correlated for pure a-Si, but not for hydrogenated a-Si, suggesting that the standard TLS model works for a-Si, but that a-Si:H possess TLS that are decoupled from the acoustic waves measured by internal friction. Internal friction measures those TLS that introduce mechanical damping; we are in the process of measuring low T dielectric loss which yield TLS with dipole moments in order to explore the correlation between different types of TLS. Additionally, a strong correlation is found between an excess T3 term (well above the sound velocity-derived Debye contribution) and the linear term in heat capacity, suggesting a common origin. I thank members of my research group and my collaborators for contributions to this work and NSF-DMR-1508828 for support.

  6. FEM Simulation of Influence of Protective Encapsulation on MEMS Pressure Sensor

    DEFF Research Database (Denmark)

    Yao, Qingshan; Janting, Jakob; Branebjerg, Jens

    2003-01-01

    The objective of the work is to evaluate the feasibility of packaging a MEMS silicon pressure sensor by using either a polymer encapsulation or a combination of a polymer encapsulation and a metallic protection Membrane (fig. 1). The potential application of the protected sensor is for harsh...... environments. Several steps of simulation are carried out:1) Comparisons of the sensitivities are made among the non-encapsulated silicon sensor, the polymer encapsulated and polymer with metal encapsulated sensor. This is for evaluating whether the encapsulating materials reduce the pressure sensitivity...... whether the metallic membrane / coating will peel off when applying the maximum pressure, which is 4000 bar leading to high shear stress between the metallic membrane and the polymer encapsulation material.3) Thermal calculations are made to evaluate the influence of the environment on the packaged sensor...

  7. Swedish encapsulation station review

    International Nuclear Information System (INIS)

    Andersson, Sven Olof; Brunzell, P.; Heibel, R.; McCarthy, J.; Pennington, C.; Rusch, C.; Varley, G.

    1998-06-01

    In the Encapsulation Station (ES) Review performed by NAC International, a number of different areas have been studied. The main objectives with the review have been to: Perform an independent review of the cost estimates for the ES presented in SKB's document 'Plan 1996'. This has been made through comparisons between the ES and BNFL's Waste Encapsulation Plant (WEP) at Sellafield as well as with the CLAB facility. Review the location of the ES (at the CLAB site or at the final repository) and its interaction with other parts of the Swedish system for spent fuel management. Review the logistics and plant capacity of the ES. Identify important safety aspects of the ES as a basis for future licensing activities. Based on NAC International's experience of casks for transport and storage of spent fuel, review the basic design of the copper/steel canister and the transport cask. This review insides design, manufacturing, handling and licensing aspects. Perform an overall comparison between the ES project and the CLAB project with the objective to identify major project risks and discuss their mitigation

  8. Swedish encapsulation station review

    Energy Technology Data Exchange (ETDEWEB)

    Andersson, Sven Olof; Brunzell, P.; Heibel, R.; McCarthy, J.; Pennington, C.; Rusch, C.; Varley, G. [NAC International, Zuerich (Switzerland)

    1998-06-01

    In the Encapsulation Station (ES) Review performed by NAC International, a number of different areas have been studied. The main objectives with the review have been to: Perform an independent review of the cost estimates for the ES presented in SKB`s document `Plan 1996`. This has been made through comparisons between the ES and BNFL`s Waste Encapsulation Plant (WEP) at Sellafield as well as with the CLAB facility. Review the location of the ES (at the CLAB site or at the final repository) and its interaction with other parts of the Swedish system for spent fuel management. Review the logistics and plant capacity of the ES. Identify important safety aspects of the ES as a basis for future licensing activities. Based on NAC International`s experience of casks for transport and storage of spent fuel, review the basic design of the copper/steel canister and the transport cask. This review insides design, manufacturing, handling and licensing aspects. Perform an overall comparison between the ES project and the CLAB project with the objective to identify major project risks and discuss their mitigation 19 refs, 9 figs, 35 tabs

  9. Phytosome and Liposome: The Beneficial Encapsulation Systems in Drug Delivery and Food Application

    Directory of Open Access Journals (Sweden)

    Nayyer Karimi

    2015-06-01

    Full Text Available Due to poor solubility in lipids, many of bioactive components (Nutraceutical materials show less bioactivity than optimal state in water solution. Phytosomes improve absorption and bioavailability of biomaterials. Liposomes, spherical shaped nanocarriers, were discovered in the 1960s by bangham. Due to their composition, variability and structural properties, liposomes and phytosomes are extremely versatile, leading to a large number of applications including pharmaceutical, cosmetics and food industrial fields. They are advanced forms of herbal formulations containing the bioactive phytoconstituents of herb extracts such as flavonoids, glycosides and terpenoids, which have good ability to transit from a hydrophilic environment into the lipid friendly environment of the outer cell membrane. They have better bioavailability and actions than the conventional herbal extracts containing dosage. Phytosome technology has increasing effect on the bioavailability of herbal extracts including ginkgo biloba, grape seed, green tea, milk thistle, ginseng, etc., and can be developed for various therapeutic uses or dietary supplements. Liposomes are composed of bilayer membranes, which are made of lipid molecules. They form when phospholipids are dispersed in aqueous media and exposed to high shear rates by using micro-fluidization or colloid mill. The mechanism for formation of liposomes is mainly the hydrophilic–hydrophobic interactions between phospholipids and water molecules. Here, we attempt to review the features of phytosomes and liposomes as well as their preparation methods and capacity in food and drug applications. Generally, it is believed that phytosomes and liposomes are suitable delivery systems for nutraceuticals, and can be widely used in food industry.

  10. Reduction of systemic exposure and toxicity of cisplatin by encapsulation in poly-lactide-co-glycolide.

    Science.gov (United States)

    Verrijk, R; Smolders, I J; Bosnie, N; Begg, A C

    1992-12-01

    The tissue distribution and normal tissue toxicity of cisplatin (cDDP) administered as poly-lactide-co-glycolide (PLAGA) microspheres, developed for loco-regional administration of cDDP to the liver, were studied in Wag/Rij rats. Venoportal administration of this formulation resulted in a reduction in total systemic and renal toxicity, which correlated with a decrease in normal tissue exposure to cDDP while maintaining high liver platinum levels. Liver-to-kidney platinum level ratios were 28 times higher after 4 h and 19 times higher after 24 h with PLAGA-cDDP microspheres than with free cDDP. Liver-to-blood platinum ratios at these times were 38 times and 36 times higher using PLAGA-cDDP. In a CC531 colon carcinoma liver micrometastases model, cytotoxicity of microsphere-released cDDP was confirmed in vivo by equal inhibition of tumor growth by PLAGA-cDDP and free cDDP over a period of 26 days. Free cDDP, however, caused significantly more histological renal damage and total body weight loss. The results were supported by the finding of higher plasma creatinine and urea concentrations 26 days after administration of free cDDP. Kidney platinum levels were 7 times lower when PLAGA-cDDP was used. These findings indicate a sparing effect on normal tissues when cDDP is targeted to the liver by formulation in PLAGA. PLAGA-cDDP microspheres may, therefore, be a useful and effective addition to current techniques of loco-regional chemotherapy for disseminated hepatic tumors.

  11. The readout system of the new H1 silicon detectors

    International Nuclear Information System (INIS)

    Buerger, J.; Hansen, K.; Lange, W.; Prell, S.; Zimmermann, W.; Henschel, H.; Haynes, W.J.; Noyes, G.W.; Joensson, L.; Gabathuler, K.; Horisberger, R.; Wagener, M.; Eichler, R.; Erdmann, W.; Niggli, H.; Pitzl, D.

    1995-03-01

    The H1 detector at HERA at DESY undergoes presently a major upgrade. In this context silicon strip detectors have been installed at beginning of 1995. The high bunch crossing frequency of HERA (10.4 MHz) demands a novel readout architecture which includes pipelining, signal processing and data reduction at a very early stage. The front end readout is hierarchically organized. The detector elements are read out by the APC chip which contains an analog pipeline and performs first background subtraction. Up to five readout chips are controlled by a Decoder Chip. The readout processor module (OnSiRoC) operates the detectors, controls the Decoder Chips and performs a first level data reduction. The paper describes the readout architecture of the H1 Silicon Detectors and performance data of the complete readout chain. (orig.)

  12. An Educational Kit Based On a Modular Silicon Photomultiplier System

    International Nuclear Information System (INIS)

    Caccia, Massimo; Chmill, Valery; Ebolese, Amedeo; Martemyanov, Alexander; Risigo, Fabio; Santoro, Romualdo; Locatelli, Marco; Pieracci, Maura; Tintori, Carlo

    2013-06-01

    Silicon Photo-Multipliers (SiPM) are state of the art light detectors with unprecedented single photon sensitivity and photon number resolving capability, representing a breakthrough in several fundamental and applied Science domains. An educational experiment based on a SiPM set-up is proposed in this article, guiding the student towards a comprehensive knowledge of this sensor technology while experiencing the quantum nature of light and exploring the statistical properties of the light pulses emitted by a LED. (authors)

  13. Production and test of the LHCf microstrip silicon system

    International Nuclear Information System (INIS)

    Bonechi, L.; Adriani, O.; Bongi, M.; Castellini, G.; D'Alessandro, R.; Faus, A.; Haguenauer, M.; Itow, Y.; Kasahara, K.; Macina, D.; Mase, T.; Masuda, K.; Matsubara, Y.; Matsumoto, H.; Menjo, H.; Mizuishi, M.; Muraki, Y.; Papini, P.; Perrot, A.L.; Ricciarini, S.

    2008-01-01

    After a preliminary installation test, successfully performed in 2007, both the detectors of the LHCf experiment are now ready to be installed at the CERN LHC accelerator for the first physics run. A beam test at SPS in September 2007 allowed to verify the performance of the apparata. Production and test of the silicon tracker developed for one of them are shortly discussed in this work.

  14. Status of the Melbourne experimental particle physics DAQ, silicon hodoscope and readout systems

    International Nuclear Information System (INIS)

    Moorhead, G.F.

    1995-01-01

    This talk will present a brief review of the current status of the Melbourne Experimental Particle Physics group's primary data acquisition system (DAQ), the associated silicon hodoscope and trigger systems, and of the tests currently underway and foreseen. Simulations of the propagation of 106-Ru β particles through the system will also be shown

  15. Sol-gel method for encapsulating molecules

    Science.gov (United States)

    Brinker, C. Jeffrey; Ashley, Carol S.; Bhatia, Rimple; Singh, Anup K.

    2002-01-01

    A method for encapsulating organic molecules, and in particular, biomolecules using sol-gel chemistry. A silica sol is prepared from an aqueous alkali metal silicate solution, such as a mixture of silicon dioxide and sodium or potassium oxide in water. The pH is adjusted to a suitably low value to stabilize the sol by minimizing the rate of siloxane condensation, thereby allowing storage stability of the sol prior to gelation. The organic molecules, generally in solution, is then added with the organic molecules being encapsulated in the sol matrix. After aging, either a thin film can be prepared or a gel can be formed with the encapsulated molecules. Depending upon the acid used, pH, and other processing conditions, the gelation time can be from one minute up to several days. In the method of the present invention, no alcohols are generated as by-products during the sol-gel and encapsulation steps. The organic molecules can be added at any desired pH value, where the pH value is generally chosen to achieve the desired reactivity of the organic molecules. The method of the present invention thereby presents a sufficiently mild encapsulation method to retain a significant portion of the activity of the biomolecules, compared with the activity of the biomolecules in free solution.

  16. Process for encapsulating radionuclides

    International Nuclear Information System (INIS)

    Brownell, L.E.; Isaacson, R.E.

    1976-01-01

    Radionuclides are immobilized in virtually an insoluble form by reacting at a temperature of at least 90 0 C as an aqueous alkaline mixture having a solution pH of at least 10, containing a source of silicon, the radionuclide waste, and a metal cation. The molar ratio of silicon to the metal cation is on the order of unity to produce a gel from which complex metalosilicates crystallize to entrap the radionuclides within the resultant condensed crystal lattice. The product is a silicious stone-like material which is virtually insoluble and nonleachable in alkaline or neutral environment. One embodiment provides for the formation of the complex metalo-silicates, such as synthetic pollucite, by gel formation with subsequent calcination to the solid product; another embodiment utilizes a hydrothermal process, either above ground or deep within basalt caverns, at greater than atmospheric pressures and a temperature between 90 and 500 0 C to form complex metalo-silicates, such as strontium aluminosilicate. Another embodiment provides for the formation of complex metalo-silicates, such as synthetic pollucite, by slurrying an alkaline mixture of bentonite or kaolinite with a source of silicon and the radionuclide waste in salt form. In each of the embodiments a mobile system is achieved whereby the metalo-silicate constituents reorient into a condensed crystal lattice forming a cage structure with the condensed metalo-silicate lattice which completely surrounds the radionuclide and traps the radionuclide therein; thus rendering the radionuclide virtually insoluble

  17. Encapsulation of nodal segments of lobelia chinensis

    Directory of Open Access Journals (Sweden)

    Weng Hing Thong

    2015-04-01

    Full Text Available Lobelia chinensis served as an important herb in traditional chinese medicine. It is rare in the field and infected by some pathogens. Therefore, encapsulation of axillary buds has been developed for in vitro propagation of L. chinensis. Nodal explants of L. chinensis were used as inclusion materials for encapsulation. Various combinations of calcium chloride and sodium alginate were tested. Encapsulation beads produced by mixing 50 mM calcium chloride and 3.5% sodium alginate supported the optimal in vitro conversion potential. The number of multiple shoots formed by encapsulated nodal segments was not significantly different from the average of shoots produced by non-encapsulated nodal segments. The encapsulated nodal segments regenerated in vitro on different medium. The optimal germination and regeneration medium was Murashige-Skoog medium. Plantlets regenerated from the encapsulated nodal segments were hardened, acclimatized and established well in the field, showing similar morphology with parent plants. This encapsulation technology would serve as an alternative in vitro regeneration system for L. chinensis.

  18. Encapsulation plant at Forsmark

    International Nuclear Information System (INIS)

    Nystroem, Anders

    2007-08-01

    SKB has already carried out a preliminary study of an encapsulation plant detached from Clab (Central interim storage for spent fuels). This stand-alone encapsulation plant was named FRINK and its assumed siting was the above-ground portion of the final repository, irrespective of the repository's location. The report previously presented was produced in cooperation with BNFL Engineering Ltd in Manchester and the fuel reception technical solution was examined by Gesellschaft fuer Nuklear-Service mbH (GNS) in Hannover and by Societe Generale pour les Techniques Nouvelles (SGN) in Paris. This report is an update of the earlier preliminary study report and is based on the assumption that the encapsulation plant and also the final repository will be sited in the Forsmark area. SKB's main alternative for siting the encapsulation plant is next to Clab. Planning of this facility is ongoing and technical solutions from the planning work have been incorporated in this report. An encapsulation plant placed in proximity to any final repository in Forsmark forms part of the alternative presentation in the application for permission to construct and operate an installation at Clab. The main technical difference between the planned encapsulation plant at Clab and an encapsulation plant at a final repository at Forsmark is how the fuel is managed and prepared before actual encapsulation. Fuel reception at the encapsulation plant in Forsmark would be dry, i.e. there would be no water-filled pools at the facility. Clab is used for verificatory fuel measurements, sorting and drying of the fuel before transport to Forsmark. This means that Clab will require a measure of rebuilding and supplementary equipment. In purely technical terms, the prospects for building an encapsulation plant sited at Forsmark are good. A description of the advantages and drawbacks of siting the encapsulation plant at Clab as opposed to any final repository at Forsmark is presented in a separate report

  19. Encapsulation plant at Forsmark

    Energy Technology Data Exchange (ETDEWEB)

    Nystroem, Anders

    2007-08-15

    SKB has already carried out a preliminary study of an encapsulation plant detached from Clab (Central interim storage for spent fuels). This stand-alone encapsulation plant was named FRINK and its assumed siting was the above-ground portion of the final repository, irrespective of the repository's location. The report previously presented was produced in cooperation with BNFL Engineering Ltd in Manchester and the fuel reception technical solution was examined by Gesellschaft fuer Nuklear-Service mbH (GNS) in Hannover and by Societe Generale pour les Techniques Nouvelles (SGN) in Paris. This report is an update of the earlier preliminary study report and is based on the assumption that the encapsulation plant and also the final repository will be sited in the Forsmark area. SKB's main alternative for siting the encapsulation plant is next to Clab. Planning of this facility is ongoing and technical solutions from the planning work have been incorporated in this report. An encapsulation plant placed in proximity to any final repository in Forsmark forms part of the alternative presentation in the application for permission to construct and operate an installation at Clab. The main technical difference between the planned encapsulation plant at Clab and an encapsulation plant at a final repository at Forsmark is how the fuel is managed and prepared before actual encapsulation. Fuel reception at the encapsulation plant in Forsmark would be dry, i.e. there would be no water-filled pools at the facility. Clab is used for verificatory fuel measurements, sorting and drying of the fuel before transport to Forsmark. This means that Clab will require a measure of rebuilding and supplementary equipment. In purely technical terms, the prospects for building an encapsulation plant sited at Forsmark are good. A description of the advantages and drawbacks of siting the encapsulation plant at Clab as opposed to any final repository at Forsmark is presented in a separate

  20. Palisaded encapsulated neuroma

    Directory of Open Access Journals (Sweden)

    Adesh S Manchanda

    2015-01-01

    Full Text Available Palisaded encapsulated neuroma (PEN is a benign cutaneous or mucosal neural tumor which, usually, presents as a solitary, firm, asymptomatic, papule or nodule showing striking predilection for the face. It occurs commonly in middle age, and there is no sex predilection. Oral PEN are not common, and these lesions must be distinguished from other peripheral nerve sheath tumors such as the neurofibroma, neurilemma (schwannoma, and traumatic neuroma. The major challenge in dealing with lesions of PEN is to avoid the misdiagnosis of neural tumors that may be associated with systemic syndromes such as neurofibromatosis and multiple endocrine neoplasia syndrome type 2B. Here, we present a case of benign PEN of the gingiva in the left anterior mandibular region, laying importance on immunohistochemical staining in diagnosing such lesions.

  1. JACK - ANTHROPOMETRIC MODELING SYSTEM FOR SILICON GRAPHICS WORKSTATIONS

    Science.gov (United States)

    Smith, B.

    1994-01-01

    JACK is an interactive graphics program developed at the University of Pennsylvania that displays and manipulates articulated geometric figures. JACK is typically used to observe how a human mannequin interacts with its environment and what effects body types will have upon the performance of a task in a simulated environment. Any environment can be created, and any number of mannequins can be placed anywhere in that environment. JACK includes facilities to construct limited geometric objects, position figures, perform a variety of analyses on the figures, describe the motion of the figures and specify lighting and surface property information for rendering high quality images. JACK is supplied with a variety of body types pre-defined and known to the system. There are both male and female bodies, ranging from the 5th to the 95th percentile, based on NASA Standard 3000. Each mannequin is fully articulated and reflects the joint limitations of a normal human. JACK is an editor for manipulating previously defined objects known as "Peabody" objects. Used to describe the figures as well as the internal data structure for representing them, Peabody is a language with a powerful and flexible mechanism for representing connectivity between objects, both the joints between individual segments within a figure and arbitrary connections between different figures. Peabody objects are generally comprised of several individual figures, each one a collection of segments. Each segment has a geometry represented by PSURF files that consist of polygons or curved surface patches. Although JACK does not have the capability to create new objects, objects may be created by other geometric modeling programs and then translated into the PSURF format. Environment files are a collection of figures and attributes that may be dynamically moved under the control of an animation file. The animation facilities allow the user to create a sequence of commands that duplicate the movements of a

  2. Development of electron temperature measuring system by silicon drift detector

    International Nuclear Information System (INIS)

    Song Xianying; Yang Jinwei; Liao Min

    2007-12-01

    Soft X-ray spectroscopy with two channels Silicon Drift Detector (SDD) are adopted for electron temperature measuring on HL-2A tokamak in 2005. The working principle, design and first operation of the SDD soft X-ray spectroscopy are introduced. The measuring results of electron temperature are also presented. The results show that the SDD is very good detector for electron temperature measuring on HL-2A tokamak. These will become a solid basic work to establish SDD array for electron temperature profiling. (authors)

  3. The development of a silicon multiplicity detector system

    Energy Technology Data Exchange (ETDEWEB)

    Beuttenmuller, R.H.; Kraner, H.W.; Lissauer, D.; Makowiecki, D.; Polychronakos, V.; Radeka, V.; Sondericker, J.; Stephani, D. [Brookhaven National Laboratory, Upton, NY (United States); Barrette, J.; Hall, J.; Mark, S.K.; Pruneau, C.A. [McGill Univ., Montreal, Quebec (Canada); Wolfe, D. [Univ. of New Mexico, Albuquerque (United States); Borenstein, S.R. [York College-CUNY, Jamaica, NY (United States)

    1991-12-31

    The physics program and the design criteria for a Silicon Pad Detector at RHIC are reviewed. An end cap double sided readout detector configuration for RHIC is presented. Its performance as an on-line and off-line centrality tagging device is studied by means of simulations with Fritiof as the event generator. The results of an in-beam test of a prototype double-sided Si-detector are presented. Good signal-to-noise ratio are obtained with front junction and the resistive back side readout. Good separation between one and two minimum-ionizing particle signals is achieved.

  4. Radiation monitoring and beam dump system of the OPAL silicon microvertex detector

    CERN Document Server

    Braibant, S

    1997-01-01

    The OPAL microvertex silicon detector radiation monitoring and beam dump system is described. This system was designed and implemented in order to measure the radiation dose received at every beam crossing and to induce a fast beam dump if the radiation dose exceeds a given threshold.

  5. Encapsulation of nuclear wastes

    International Nuclear Information System (INIS)

    Arnold, J.L.; Boyle, R.W.

    1978-01-01

    Toxic waste materials are encapsulated by the method wherein the waste material in liquid or finely divided solid form is uniformly dispersed in a vinyl ester resin or an unsaturated polyester and the resin cured under conditions that the exotherm does not rise above the temperature at which the integrity of the encapsulating material is destroyed

  6. Overview of CMS robotic silicon module assembly hardware based on Aerotech Gantry Positioning system.

    CERN Multimedia

    Honma, Alan

    1999-01-01

    The goal of the robotic silicon module assembly pilot project is to fully automate the gluing and pick and placement of silicon sensors and front-end hybrid onto a carbon-fibre frame. The basis for thesystem is the Aerotech Gantry Positioning System (AGS10000) machineshown in the centre of the picture. To the left is the PC which contains the controller card and runs the user interface. To the rightis the rack of associated electronics which interfaces with the CERNbuilt tooling and vacuum chuck system.

  7. Systemic Sclerosis and Silicone Breast Implant: A Case Report and Review of the Literature

    Directory of Open Access Journals (Sweden)

    Antonios Psarras

    2014-01-01

    Full Text Available Environmentally induced systemic sclerosis is a well-recognized condition, which is correlated with exposure to various chemical compounds or drugs. However, development of scleroderma-like disease after exposure to silicone has always been a controversial issue and, over time, it has triggered spirited debate whether there is a certain association or not. Herein, we report the case of a 35-year-old female who developed Raynaud’s phenomenon and, finally, systemic sclerosis shortly after silicone breast implantation surgery.

  8. Acoustically excited encapsulated microbubbles and mitigation of biofouling

    KAUST Repository

    Qamar, Adnan

    2017-08-31

    Provided herein is a universally applicable biofouling mitigation technology using acoustically excited encapsulated microbubbles that disrupt biofilm or biofilm formation. For example, a method of reducing biofilm formation or removing biofilm in a membrane filtration system is provided in which a feed solution comprising encapsulated microbubbles is provided to the membrane under conditions that allow the encapsulated microbubbles to embed in a biofilm. Sonication of the embedded, encapsulated microbubbles disrupts the biofilm. Thus, provided herein is a membrane filtration system for performing the methods and encapsulated microbubbles specifically selected for binding to extracellular polymeric substances (EFS) in a biofilm.

  9. Vanadium supersaturated silicon system: a theoretical and experimental approach

    Science.gov (United States)

    Garcia-Hemme, Eric; García, Gregorio; Palacios, Pablo; Montero, Daniel; García-Hernansanz, Rodrigo; Gonzalez-Diaz, Germán; Wahnon, Perla

    2017-12-01

    The effect of high dose vanadium ion implantation and pulsed laser annealing on the crystal structure and sub-bandgap optical absorption features of V-supersaturated silicon samples has been studied through the combination of experimental and theoretical approaches. Interest in V-supersaturated Si focusses on its potential as a material having a new band within the Si bandgap. Rutherford backscattering spectrometry measurements and formation energies computed through quantum calculations provide evidence that V atoms are mainly located at interstitial positions. The response of sub-bandgap spectral photoconductance is extended far into the infrared region of the spectrum. Theoretical simulations (based on density functional theory and many-body perturbation in GW approximation) bring to light that, in addition to V atoms at interstitial positions, Si defects should also be taken into account in explaining the experimental profile of the spectral photoconductance. The combination of experimental and theoretical methods provides evidence that the improved spectral photoconductance up to 6.2 µm (0.2 eV) is due to new sub-bandgap transitions, for which the new band due to V atoms within the Si bandgap plays an essential role. This enables the use of V-supersaturated silicon in the third generation of photovoltaic devices.

  10. New technologies of silicon position-sensitive detectors for future tracker systems

    CERN Document Server

    Bassignana, Daniela; Lozano, M

    In view of the new generation of high luminosity colliders, HL-LHC and ILC, a farther investigation of silicon radiation detectors design and technology is demanded, in order to satisfy the stringent requirements of the experiments at such sophisticated machines. In this thesis, innovative technologies of silicon radiation detectors for future tracking systems are proposed. Three dierent devices have been studied and designed with the help of dierent tools for computer simulations. They have been manufactured in the IMB-CNM clean room facilities in Barcelona and characterized with proper experimental set-ups in order to test the detectors capabilities and the quality and suitability of the technologies used for their fabrication. The rst technology deals with the upgrade of dedicated sensors for laser alignment systems in future tracker detectors. The design and technology of common single-sided silicon microstrip detectors have been slightly modied in order to improve IR light transmittance of the devices. T...

  11. Ramizol® encapsulation into extended release PLGA micro- and nanoparticle systems for subcutaneous and intramuscular administration: in vitro and in vivo evaluation.

    Science.gov (United States)

    Wright, Leah; Rao, Shasha; Thomas, Nicky; Boulos, Ramiz A; Prestidge, Clive A

    2018-04-11

    Novel antibiotic Ramizol ® is advancing to clinical trials for the treatment of gastrointestinal Clostridium difficile associated disease. Despite this, previous studies have shown a rapid plasma clearance upon intravenous administration and low oral bioavailability indicating pure drug is unsuitable for systemic infection treatment following oral dosing. The current study aims to investigate the development of poly-lactic-(co-glycolic) acid (PLGA) particles to overcome this limitation and increase the systemic half-life following subcutaneous and intramuscular dosing. The development of new antibiotic treatments will help in combatting the rising incidence of antimicrobial resistance. Ramizol ® was encapsulated into PLGA nano and microparticles using nanoprecipitation and emulsification solvent evaporation techniques. Formulations were analyzed for particle size, loading level and encapsulation efficiency as well as in vitro drug release profiles. Final formulation was advanced to in vivo pharmacokinetic studies in Sprague-Dawley rats. Formulation technique showed major influence on particle size and loading levels with optimal loading of 9.4% and encapsulation efficiency of 92.06%, observed using emulsification solvent evaporation. Differences in formulation technique were also linked with subsequent differences in release profiles. Pharmacokinetic studies in Sprague-Dawley rats confirmed extended absorption and enhanced bioavailability following subcutaneous and intramuscular dosing with up to an 8-fold increase in T max and T 1/2 when compared to the oral and IV routes. Subcutaneous and intramuscular dosing of PLGA particles successfully increased systemic half-life and bioavailability of Ramizol ® . This formulation will allow further development of Ramizol ® for systemic infection eradication.

  12. XANES at the silicon k-edge in the kaolin-meta kaolin-geopolymer system

    International Nuclear Information System (INIS)

    Lima, F.T.; Silva, F.J.; Thaumaturgo, C.

    2005-01-01

    The geo polymer synthesis process optimization pretends to control the re logical and mechanical properties. The Al/Si ratio is the main variable that governs the geo polymerization process. This control occurs by changing temperature, pressure and chemical composition of the geo polymer. Thermal analysis (DTA/DSC), microscopic (SEM/TEM) and spectroscopic (FTIR, XRD, SAXS, EXAFS and XANES) techniques have been used to characterize these inorganic systems. In this work, XANES spectra of the k-edge silicon (Si) of the kaolin-meta kaolin-geo polymer are presented. The XANES spectra provides the oxidation state and structural information about the present studied atom: Silicon (Si). (author)

  13. Quality assurance tests of the CBM silicon tracking system sensors with an infrared laser

    Energy Technology Data Exchange (ETDEWEB)

    Teklishyn, Maksym [FAIR GmbH, Darmstadt (Germany); KINR, Kyiv (Ukraine); Collaboration: CBM-Collaboration

    2016-07-01

    Double-sided 300 μm thick silicon microstrip sensors are planned to be used in the Silicon Tracking System (STS) of the future CBM experiment. Different tools, including an infrared laser, are used to induce charge in the sensor medium to study the sensor response. We use present installation to develop a procedure for the sensor quality assurance during mass production. The precise positioning of the laser spot allows to make a clear judgment about the sensor interstrip gap response which provides information about the charge distribution inside the sensor medium. Results are compared with the model estimations.

  14. A Silicon SPECT System for Molecular Imaging of the Mouse Brain

    OpenAIRE

    Shokouhi, Sepideh; Fritz, Mark A.; McDonald, Benjamin S.; Durko, Heather L.; Furenlid, Lars R.; Wilson, Donald W.; Peterson, Todd E.

    2007-01-01

    We previously demonstrated the feasibility of using silicon double-sided strip detectors (DSSDs) for SPECT imaging of the activity distribution of iodine-125 using a 300-micrometer thick detector. Based on this experience, we now have developed fully customized silicon DSSDs and associated readout electronics with the intent of developing a multi-pinhole SPECT system. Each DSSD has a 60.4 mm × 60.4 mm active area and is 1 mm thick. The strip pitch is 59 micrometers, and the readout of the 102...

  15. Peculiarities of phase transformations in molybdenum-silicon system under ion bombardment

    International Nuclear Information System (INIS)

    Gurskij, L.I.; Zelenin, V.A.; Bobchenok, Yu.L.

    1984-01-01

    The problems of effect of ion bombardment and thermal treatment on the mechanisms of formation of transition layers and structural transformations in the molybdenum-silicon system, where the interface is subjected to ion bombardment through a film of molybdenum, are considered. The method of electron diffraction analysis has been applied to establish that at the molybdenum-silicon interface a transitional region appears during irradiation which has a semiamorphous structure at the doses up to 8x10 14 ion/cm 2 , while at higher doses it transforms into polycrystalline intermediate layer which consists of MoB and the compound close in composition to MoSisub(0.65). Due to thermal treatment for 60873 K a large-grain phase (Mo 3 Si+MoSi 2 ) appears in the transition layer below which a large-grain silicon layer is placed

  16. Amorphous Silicon Position Detectors for the Link Alignment System of the CMS Detector: Users Handbook

    Energy Technology Data Exchange (ETDEWEB)

    Calderon, A.; Gomez, G.; Gonzalez-Sanchez, F. J.; Martinez-Rivero, C.; Matorras, F.; Rodrigo, T.; Ruiz-Arbol, P.; Scodellaro, L.; Vila, I.; Virto, A. L.; Alberdi, J.; Arce, P.; Barcala, J.M.; Calvo, E.; Ferrando, A.; Josa, M. I.; Molinero, A.; Navarrete, J.; Oller, J. C.; Yuste, C.

    2007-07-01

    We present the general characteristics, calibration procedures and measured performance of the Amorphous Silicon Position Detectors installed in the Link Alignment System of the CMS Detector for laser beam detection and reconstruction and give the Data Base to be used as a Handbook during CMS operation. (Author) 10 refs.

  17. Amorphous Silicon Position Detectors for the Link Alignment System of the CMS Detector: Users Handbook

    International Nuclear Information System (INIS)

    Calderon, A.; Gomez, G.; Gonzalez-Sanchez, F. J.; Martinez-Rivero, C.; Matorras, F.; Rodrigo, T.; Ruiz-Arbol, P.; Scodellaro, L.; Vila, I.; Virto, A. L.; Alberdi, J.; Arce, P.; Barcala, J.M.; Calvo, E.; Ferrando, A.; Josa, M. I.; Molinero, A.; Navarrete, J.; Oller, J. C.; Yuste, C.

    2007-01-01

    We present the general characteristics, calibration procedures and measured performance of the Amorphous Silicon Position Detectors installed in the Link Alignment System of the CMS Detector for laser beam detection and reconstruction and give the Data Base to be used as a Handbook during CMS operation. (Author) 10 refs

  18. A low power bipolar amplifier integrated circuit for the ZEUS silicon strip system

    Energy Technology Data Exchange (ETDEWEB)

    Barberis, E. (Inst. for Particle Physics, Univ. of California, Santa Cruz, CA (United States)); Cartiglia, N. (Inst. for Particle Physics, Univ. of California, Santa Cruz, CA (United States)); Dorfan, D.E. (Inst. for Particle Physics, Univ. of California, Santa Cruz, CA (United States)); Spencer, E. (Inst. for Particle Physics, Univ. of California, Santa Cruz, CA (United States))

    1993-05-01

    A fast low power bipolar chip consisting of 64 amplifier-comparators has been developed for use with silicon strip detectors for systems where high radiation levels and high occupancy considerations are important. The design is described and test results are presented. (orig.)

  19. Photopolymerizable liquid encapsulants for microelectronic devices

    Science.gov (United States)

    Baikerikar, Kiran K.

    2000-10-01

    Plastic encapsulated microelectronic devices consist of a silicon chip that is physically attached to a leadframe, electrically interconnected to input-output leads, and molded in a plastic that is in direct contact with the chip, leadframe, and interconnects. The plastic is often referred to as the molding compound, and is used to protect the chip from adverse mechanical, thermal, chemical, and electrical environments. Encapsulation of microelectronic devices is typically accomplished using a transfer molding process in which the molding compound is cured by heat. Most transfer molding processes suffer from significant problems arising from the high operating temperatures and pressures required to fill the mold. These aspects of the current process can lead to thermal stresses, incomplete mold filling, and wire sweep. In this research, a new strategy for encapsulating microelectronic devices using photopolymerizable liquid encapsulants (PLEs) has been investigated. The PLEs consist of an epoxy novolac-based vinyl ester resin (˜25 wt.%), fused silica filler (70--74 wt.%), and a photoinitiator, thermal initiator, and silane coupling agent. For these encapsulants, the use of light, rather than heat, to initiate the polymerization allows precise control over when the reaction starts, and therefore completely decouples the mold filling and the cure. The low viscosity of the PLEs allows for low operating pressures and minimizes problems associated with wire sweep. In addition, the in-mold cure time for the PLEs is equivalent to the in-mold cure times of current transfer molding compounds. In this thesis, the thermal and mechanical properties, as well as the viscosity and adhesion of photopolymerizable liquid encapsulants, are reported in order to demonstrate that a UV-curable formulation can have the material properties necessary for microelectronic encapsulation. In addition, the effects of the illumination time, postcure time, fused silica loading, and the inclusion

  20. Enzyme biosensor systems based on porous silicon photoluminescence for detection of glucose, urea and heavy metals.

    Science.gov (United States)

    Syshchyk, Olga; Skryshevsky, Valeriy A; Soldatkin, Oleksandr O; Soldatkin, Alexey P

    2015-04-15

    A phenomenon of changes in photoluminescence of porous silicon at variations in medium pH is proposed to be used as a basis for the biosensor system development. The method of conversion of a biochemical signal into an optical one is applied for direct determination of glucose and urea as well as for inhibitory analysis of heavy metal ions. Changes in the quantum yield of porous silicon photoluminescence occur at varying pH of the tested solution due to the enzyme-substrate reaction. When creating the biosensor systems, the enzymes urease and glucose oxidase (GOD) were used as a bioselective material; their optimal concentrations were experimentally determined. It was shown that the photoluminescence intensity of porous silicon increased by 1.7 times when increasing glucose concentration in the GOD-containing reaction medium from 0 to 3.0mM, and decreased by 1.45 times at the same increase in the urea concentration in the urease-containing reaction medium. The calibration curves of dependence of the biosensor system responses on the substrate concentrations are presented. It is shown that the presence of heavy metal ions (Cu(2+), Pb(2+), and Cd(2+)) in the tested solution causes an inhibition of the enzymatic reactions catalyzed by glucose oxidase and urease, which results in a restoration of the photoluminescence quantum yield of porous silicon. It is proposed to use this effect for the inhibitory analysis of heavy metal ions. Copyright © 2014 Elsevier B.V. All rights reserved.

  1. Encapsulation with structured triglycerides

    Science.gov (United States)

    Lipids provide excellent materials to encapsulate bioactive compounds for food and pharmaceutical applications. Lipids are renewable, biodegradable, and easily modified to provide additional chemical functionality. The use of structured lipids that have been modified with photoactive properties are ...

  2. Embolization of carotid-cavernous fistula using a silicone balloon and a tracker-catheter system

    International Nuclear Information System (INIS)

    Kim, Sun Yong; Cho, Kil Ho; Park, Bok Hwan

    1992-01-01

    With the recent introduction and development of the detachable balloon system, it has become the treatment of choice in the management of carotid cavernous fistulas(CCFs). But, since most delivery systems for embolization of CCF mainly depend on flow guidance for balloon delivery, in case of small fistula, pseudo aneurysm and arterialized venous collaterals, failure of balloon embolization can occur. To overcome these limitation, the authors designed and used a new versatile, steerable, and flow-guided detachable balloon system by using a Tracker catheter system with silicone or latex balloons. Using this maneuver, we could get successful fistula occlusion in 7 out of 8 patients (silicone balloon). But in one case, we had to occlude the internal carotid artery at the fistula site, proximal and distal cervical portions of the internal carotid artery. This balloon delivery system proved to provide high selectivity for fistula and relatively ease of handing

  3. Injectable Thermoresponsive Hydrogel Formed by Alginate-g-Poly(N-isopropylacrylamide) That Releases Doxorubicin-Encapsulated Micelles as a Smart Drug Delivery System.

    Science.gov (United States)

    Liu, Min; Song, Xia; Wen, Yuting; Zhu, Jing-Ling; Li, Jun

    2017-10-18

    In this work, we have synthesized a thermoresponsive copolymer, alginate-g-poly(N-isopropylacrylamide) (alginate-g-PNIPAAm) by conjugating PNIPAAm to alginate, where PNIPAAm with different molecular weights and narrow molecular weight distribution was synthesized by atomic transfer radical polymerization. The copolymer dissolved in water or phosphate-buffered saline buffer solution at room temperature and formed self-assembled micelles with low critical micellization concentrations when the temperature increased to above their critical micellization temperatures. At higher concentration, that is, 7.4 wt % in water, the copolymer formed solutions at 25 °C and turned into thermosensitive hydrogels when temperature increased to the body temperature (37 °C). Herein, we hypothesized that the thermoresponsive hydrogels could produce self-assembled micelles with the dissolution of the alginate-g-PNIPAAm hydrogels in a biological fluid or drug release medium. If the drug was hydrophobic, the hydrogel eventually could release and produce drug-encapsulated micelles. In our experiments, we loaded the anticancer drug doxorubicin (DOX) into the alginate-g-PNIPAAm hydrogels and demonstrated that the hydrogels released DOX-encapsulated micelles in a sustained manner. The slowly released DOX-loaded micelles enhanced the cellular uptake of DOX in multidrug resistant AT3B-1 cells, showing the effect of overcoming the drug resistance and achieving better efficiency for killing the cancer cells. Therefore, the injectable thermoresponsive hydrogels formed by alginate-g-PNIPAAm and loaded with DOX turned into a smart drug delivery system, releasing DOX-encapsulated micelles in a sustained manner, showing great potential for overcoming the drug resistance in cancer therapy.

  4. Design and development of fluidized bed reactor system for production of trichlorosilane as a precursor for high purity silicon

    International Nuclear Information System (INIS)

    Kumar, Rajesh; Mohan, Sadhana; Bhanja, K.; Nayak, S.; Bhattacharya, S.K.

    2009-01-01

    Trichlorosilane is widely used as precursor material for production of high purity silicon. It is mainly produced by reaction of metallurgical grade silicon with anhydrous HCl gas in a fluidized bed reactor. To develop this process on commercial scale a pilot size fluidized bed reactor system was designed and developed and successfully operated. This paper discusses the critical issues related to these activities. (author)

  5. Nuclear-waste encapsulation by metal-matrix casting

    International Nuclear Information System (INIS)

    Nelson, R.G.; Nesbitt, J.F.; Slate, S.C.

    1981-05-01

    Several encapsulation casting processes are described that were developed or used at the Pacific Northwest Laboratory to embed simulated high-level wastes of two different forms (glass marbles and ceramic pellets) in metal matrices. Preliminary evaluations of these casting processes and the products are presented. Demonstrations have shown that 5- to 10-mm-dia glass marbles can be encapsulated on an engineering scale with lead or lead alloys by gravity or vacuum processes. Marbles approx. 12 mm in dia were successfully encapsulated in a lead alloy on a production scale. Also, 4- to 9-mm-dia ceramic pellets in containers of various sizes were completely penetrated and the individual pellets encased with aluminum-12 wt % silicon alloy by vacuum processes. Indications are that of the casting processes tested, aluminum 12 wt % silicon alloy vacuum-cast around ceramic pellets had the highest degree of infiltration or coverage of pellet surfaces

  6. Oil Contact Angles in a Water-Decane-Silicon Dioxide System: Effects of Surface Charge.

    Science.gov (United States)

    Xu, Shijing; Wang, Jingyao; Wu, Jiazhong; Liu, Qingjie; Sun, Chengzhen; Bai, Bofeng

    2018-04-19

    Oil wettability in the water-oil-rock systems is very sensitive to the evolution of surface charges on the rock surfaces induced by the adsorption of ions and other chemical agents in water flooding. Through a set of large-scale molecular dynamics simulations, we reveal the effects of surface charge on the oil contact angles in an ideal water-decane-silicon dioxide system. The results show that the contact angles of oil nano-droplets have a great dependence on the surface charges. As the surface charge density exceeds a critical value of 0.992 e/nm 2 , the contact angle reaches up to 78.8° and the water-wet state is very apparent. The variation of contact angles can be confirmed from the number density distributions of oil molecules. With increasing the surface charge density, the adsorption of oil molecules weakens and the contact areas between nano-droplets and silicon dioxide surface are reduced. In addition, the number density distributions, RDF distributions, and molecular orientations indicate that the oil molecules are adsorbed on the silicon dioxide surface layer-by-layer with an orientation parallel to the surface. However, the layered structure of oil molecules near the silicon dioxide surface becomes more and more obscure at higher surface charge densities.

  7. A Three-Dimensional Microdisplacement Sensing System Based on MEMS Bulk-Silicon Technology

    Science.gov (United States)

    Wu, Junjie; Lei, Lihua; Chen, Xin; Cai, Xiaoyu; Li, Yuan; Han, Tao

    2014-01-01

    For the dimensional measurement and characterization of microsized and nanosized components, a three-dimensional microdisplacement sensing system was developed using the piezoresistive effect in silicon. The sensor was fabricated using microelectromechanical system bulk-silicon technology, and it was validated using the finite element method. A precise data acquisition circuit with an accuracy of 20 μV was designed to obtain weak voltage signals. By calibration, the sensing system was shown to have a sensitivity of 17.29 mV/μm and 4.59 mV/μm in the axial and lateral directions, respectively; the nonlinearity in these directions was 0.8% and 1.0% full scale, respectively. A full range of 4.6 μm was achieved in the axial direction. Results of a resolution test indicated that the sensing system had a resolution of 5 nm in the axial direction and 10 nm in the lateral direction. PMID:25360581

  8. Preliminary thoughts on the data acquisition for the next generation of silicon tracking systems

    International Nuclear Information System (INIS)

    Genat, J.F.; Savoy-Navarro, A.

    2007-01-01

    Preliminary thoughts about the data acquisition system to be developed for the next generation of large area silicon tracker are presented in this paper. This paper describes the set of data delivered by these tracking systems, and the various stages of processing and data flow transmission from the front-end chip sitting on the detector to the latest stage in the data processing. How to best profit from the status of the art technologies is a major goal. (author)

  9. Gravity Probe B Encapsulated

    Science.gov (United States)

    2004-01-01

    In this photo, the Gravity Probe B (GP-B) space vehicle is being encapsulated atop the Delta II launch vehicle. The GP-B is the relativity experiment developed at Stanford University to test two extraordinary predictions of Albert Einstein's general theory of relativity. The experiment will measure, very precisely, the expected tiny changes in the direction of the spin axes of four gyroscopes contained in an Earth-orbiting satellite at a 400-mile altitude. So free are the gyroscopes from disturbance that they will provide an almost perfect space-time reference system. They will measure how space and time are very slightly warped by the presence of the Earth, and, more profoundly, how the Earth's rotation very slightly drags space-time around with it. These effects, though small for the Earth, have far-reaching implications for the nature of matter and the structure of the Universe. GP-B is among the most thoroughly researched programs ever undertaken by NASA. This is the story of a scientific quest in which physicists and engineers have collaborated closely over many years. Inspired by their quest, they have invented a whole range of technologies that are already enlivening other branches of science and engineering. Launched April 20, 2004 , the GP-B program was managed for NASA by the Marshall Space Flight Center. Development of the GP-B is the responsibility of Stanford University along with major subcontractor Lockheed Martin Corporation. (Image credit to Russ Underwood, Lockheed Martin Corporation).

  10. A model for acoustic vaporization dynamics of a bubble/droplet system encapsulated within a hyperelastic shell.

    Science.gov (United States)

    Lacour, Thomas; Guédra, Matthieu; Valier-Brasier, Tony; Coulouvrat, François

    2018-01-01

    Nanodroplets have great, promising medical applications such as contrast imaging, embolotherapy, or targeted drug delivery. Their functions can be mechanically activated by means of focused ultrasound inducing a phase change of the inner liquid known as the acoustic droplet vaporization (ADV) process. In this context, a four-phases (vapor + liquid + shell + surrounding environment) model of ADV is proposed. Attention is especially devoted to the mechanical properties of the encapsulating shell, incorporating the well-known strain-softening behavior of Mooney-Rivlin material adapted to very large deformations of soft, nearly incompressible materials. Various responses to ultrasound excitation are illustrated, depending on linear and nonlinear mechanical shell properties and acoustical excitation parameters. Different classes of ADV outcomes are exhibited, and a relevant threshold ensuring complete vaporization of the inner liquid layer is defined. The dependence of this threshold with acoustical, geometrical, and mechanical parameters is also provided.

  11. Three-dimensional printed polymeric system to encapsulate human mesenchymal stem cells differentiated into islet-like insulin-producing aggregates for diabetes treatment

    Directory of Open Access Journals (Sweden)

    Omaima M Sabek

    2016-04-01

    Full Text Available Diabetes is one of the most prevalent, costly, and debilitating diseases in the world. Pancreas and islet transplants have shown success in re-establishing glucose control and reversing diabetic complications. However, both are limited by donor availability, need for continuous immunosuppression, loss of transplanted tissue due to dispersion, and lack of vascularization. To overcome the limitations of poor islet availability, here, we investigate the potential of bone marrow–derived mesenchymal stem cells differentiated into islet-like insulin-producing aggregates. Islet-like insulin-producing aggregates, characterized by gene expression, are shown to be similar to pancreatic islets and display positive immunostaining for insulin and glucagon. To address the limits of current encapsulation systems, we developed a novel three-dimensional printed, scalable, and potentially refillable polymeric construct (nanogland to support islet-like insulin-producing aggregates’ survival and function in the host body. In vitro studies showed that encapsulated islet-like insulin-producing aggregates maintained viability and function, producing steady levels of insulin for at least 4 weeks. Nanogland—islet-like insulin-producing aggregate technology here investigated as a proof of concept holds potential as an effective and innovative approach for diabetes cell therapy.

  12. Three-dimensional printed polymeric system to encapsulate human mesenchymal stem cells differentiated into islet-like insulin-producing aggregates for diabetes treatment.

    Science.gov (United States)

    Sabek, Omaima M; Farina, Marco; Fraga, Daniel W; Afshar, Solmaz; Ballerini, Andrea; Filgueira, Carly S; Thekkedath, Usha R; Grattoni, Alessandro; Gaber, A Osama

    2016-01-01

    Diabetes is one of the most prevalent, costly, and debilitating diseases in the world. Pancreas and islet transplants have shown success in re-establishing glucose control and reversing diabetic complications. However, both are limited by donor availability, need for continuous immunosuppression, loss of transplanted tissue due to dispersion, and lack of vascularization. To overcome the limitations of poor islet availability, here, we investigate the potential of bone marrow-derived mesenchymal stem cells differentiated into islet-like insulin-producing aggregates. Islet-like insulin-producing aggregates, characterized by gene expression, are shown to be similar to pancreatic islets and display positive immunostaining for insulin and glucagon. To address the limits of current encapsulation systems, we developed a novel three-dimensional printed, scalable, and potentially refillable polymeric construct (nanogland) to support islet-like insulin-producing aggregates' survival and function in the host body. In vitro studies showed that encapsulated islet-like insulin-producing aggregates maintained viability and function, producing steady levels of insulin for at least 4 weeks. Nanogland-islet-like insulin-producing aggregate technology here investigated as a proof of concept holds potential as an effective and innovative approach for diabetes cell therapy.

  13. Development of a CO{sub 2} cooling system for the CBM silicon tracking system

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez Rosado, Jorge; Degirmenciler, Burak; Heuser, Johann; Sturm, Christian [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH (Germany); Lymanets, Anton; Schmidt, Hans Rudolf [Eberhard Karls Universitaet Tuebingen (Germany)

    2015-07-01

    The demanding requirements of current high-energy physics experiments curiously bring back the idea of using a well-known and present refrigerant in nature: CO{sub 2}. As an outcome of previous studies and effort made within the current upgrade programs of detectors like ATLAS or CMS, this refrigerant is the optimum solution. Due to its highest volumetric heat transfer coefficient, it fulfills the requirements in this kind of detectors such as reduction of mass budget and the use of smaller diameter for cooling pipes. A two-phase (evaporative) CO{sub 2} cooling system is taken as the first choice to extract the 42 kW dissipated by the electronics of the Silicon Tracking System, the central detector of the CBM experiment at FAIR that will be installed in the gap of the 1 T super-conducting dipole magnet in a confined volume of 2 m{sup 3}. As a step towards the final design of this a cooling system, a 1 kW cooling unit called TRACI-XL was conceived at GSI in cooperation with CERN. This scaled prototype allows gaining insight into the behavior of the full system with valuable conclusions in terms of thermodynamics, process engineering and automation.

  14. A Silicon SPECT System for Molecular Imaging of the Mouse Brain.

    Science.gov (United States)

    Shokouhi, Sepideh; Fritz, Mark A; McDonald, Benjamin S; Durko, Heather L; Furenlid, Lars R; Wilson, Donald W; Peterson, Todd E

    2007-01-01

    We previously demonstrated the feasibility of using silicon double-sided strip detectors (DSSDs) for SPECT imaging of the activity distribution of iodine-125 using a 300-micrometer thick detector. Based on this experience, we now have developed fully customized silicon DSSDs and associated readout electronics with the intent of developing a multi-pinhole SPECT system. Each DSSD has a 60.4 mm × 60.4 mm active area and is 1 mm thick. The strip pitch is 59 micrometers, and the readout of the 1024 strips on each side gives rise to a detector with over one million pixels. Combining four high-resolution DSSDs into a SPECT system offers an unprecedented space-bandwidth product for the imaging of single-photon emitters. The system consists of two camera heads with two silicon detectors stacked one behind the other in each head. The collimator has a focused pinhole system with cylindrical-shaped pinholes that are laser-drilled in a 250 μm tungsten plate. The unique ability to collect projection data at two magnifications simultaneously allows for multiplexed data at high resolution to be combined with lower magnification data with little or no multiplexing. With the current multi-pinhole collimator design, our SPECT system will be capable of offering high spatial resolution, sensitivity and angular sampling for small field-of-view applications, such as molecular imaging of the mouse brain.

  15. Performance Analysis of a Grid-Connected Upgraded Metallurgical Grade Silicon Photovoltaic System

    Directory of Open Access Journals (Sweden)

    Chao Huang

    2016-05-01

    Full Text Available Because of their low cost, photovoltaic (PV cells made from upgraded metallurgical grade silicon (UMG-Si are a promising alternative to conventional solar grade silicon-based PV cells. This study investigates the outdoor performance of a 1.26 kW grid-connected UMG-Si PV system over five years, reporting the energy yields and performance ratio and estimating the long-term performance degradation rate. To make this investigation more meaningful, the performance of a mono-Si PV system installed at the same place and studied during the same period of time is presented for reference. Furthermore, this study systematizes and rationalizes the necessity of a data selection and filtering process to improve the accuracy of degradation rate estimation. The impact of plane-of-array irradiation threshold for data filtering on performance ratio and degradation rate is also studied. The UMG-Si PV system’s monthly performance ratio after data filtering ranged from 84% to 93% over the observation period. The annual degradation rate was 0.44% derived from time series of monthly performance ratio using the classical decomposition method. A comparison of performance ratio and degradation rate to conventional crystalline silicon-based PV systems suggests that performance of the UMG-Si PV system is comparable to that of conventional systems.

  16. Development of a Test System for the Quality Assurance of Silicon Microstrip Detectors for the Inner Tracking System of the CMS Experiment

    CERN Document Server

    Axer, Markus

    2003-01-01

    The inner tracking system of the Compact Muon Solenoid (CMS) experiment at the Large Hadron Collider (LHC) which is being built at the European Laboratory for Particle Physics CERN (Geneva, Switzerland) will be equipped with two different technologies of silicon detectors. While the innermost tracker will be composed of silicon pixel detectors, silicon microstrip detectors are envisaged for the outer tracker architecture. The silicon microstrip tracker will house about 15,000 single detector modules each composed of a set of silicon sensors, the readout electronics (front end hybrid), and a support frame. It will provide a total active area of 198 m2 and ten million analogue channels read out at the collider frequency of 40 MHz. This large number of modules to be produced and integrated into the tracking system is an unprecedented challenge involving industrial companies and various research institutes from many different countries. This thesis deals with the physics of silicon sensors and the preparation of ...

  17. Revision of Import and Export Requirements for Controlled Substances, Listed Chemicals, and Tableting and Encapsulating Machines, Including Changes To Implement the International Trade Data System (ITDS); Revision of Reporting Requirements for Domestic Transactions in Listed Chemicals and Tableting and Encapsulating Machines; and Technical Amendments. Final rule.

    Science.gov (United States)

    2016-12-30

    The Drug Enforcement Administration is updating its regulations for the import and export of tableting and encapsulating machines, controlled substances, and listed chemicals, and its regulations relating to reports required for domestic transactions in listed chemicals, gamma-hydroxybutyric acid, and tableting and encapsulating machines. In accordance with Executive Order 13563, the Drug Enforcement Administration has reviewed its import and export regulations and reporting requirements for domestic transactions in listed chemicals (and gamma-hydroxybutyric acid) and tableting and encapsulating machines, and evaluated them for clarity, consistency, continued accuracy, and effectiveness. The amendments clarify certain policies and reflect current procedures and technological advancements. The amendments also allow for the implementation, as applicable to tableting and encapsulating machines, controlled substances, and listed chemicals, of the President's Executive Order 13659 on streamlining the export/import process and requiring the government-wide utilization of the International Trade Data System (ITDS). This rule additionally contains amendments that implement recent changes to the Controlled Substances Import and Export Act (CSIEA) for reexportation of controlled substances among members of the European Economic Area made by the Improving Regulatory Transparency for New Medical Therapies Act. The rule also includes additional substantive and technical and stylistic amendments.

  18. Integrating photonics with silicon nanoelectronics for the next generation of systems on a chip.

    Science.gov (United States)

    Atabaki, Amir H; Moazeni, Sajjad; Pavanello, Fabio; Gevorgyan, Hayk; Notaros, Jelena; Alloatti, Luca; Wade, Mark T; Sun, Chen; Kruger, Seth A; Meng, Huaiyu; Al Qubaisi, Kenaish; Wang, Imbert; Zhang, Bohan; Khilo, Anatol; Baiocco, Christopher V; Popović, Miloš A; Stojanović, Vladimir M; Ram, Rajeev J

    2018-04-01

    Electronic and photonic technologies have transformed our lives-from computing and mobile devices, to information technology and the internet. Our future demands in these fields require innovation in each technology separately, but also depend on our ability to harness their complementary physics through integrated solutions 1,2 . This goal is hindered by the fact that most silicon nanotechnologies-which enable our processors, computer memory, communications chips and image sensors-rely on bulk silicon substrates, a cost-effective solution with an abundant supply chain, but with substantial limitations for the integration of photonic functions. Here we introduce photonics into bulk silicon complementary metal-oxide-semiconductor (CMOS) chips using a layer of polycrystalline silicon deposited on silicon oxide (glass) islands fabricated alongside transistors. We use this single deposited layer to realize optical waveguides and resonators, high-speed optical modulators and sensitive avalanche photodetectors. We integrated this photonic platform with a 65-nanometre-transistor bulk CMOS process technology inside a 300-millimetre-diameter-wafer microelectronics foundry. We then implemented integrated high-speed optical transceivers in this platform that operate at ten gigabits per second, composed of millions of transistors, and arrayed on a single optical bus for wavelength division multiplexing, to address the demand for high-bandwidth optical interconnects in data centres and high-performance computing 3,4 . By decoupling the formation of photonic devices from that of transistors, this integration approach can achieve many of the goals of multi-chip solutions 5 , but with the performance, complexity and scalability of 'systems on a chip' 1,6-8 . As transistors smaller than ten nanometres across become commercially available 9 , and as new nanotechnologies emerge 10,11 , this approach could provide a way to integrate photonics with state-of-the-art nanoelectronics.

  19. A Fastbus-based silicon strip readout system

    International Nuclear Information System (INIS)

    Neoustroev, P.; Stepanov, V.; Svoiski, M.; Uvarov, L.; Matthew, P.; Russ, J.; Cooper, P.

    1995-01-01

    The readout system we describe here is built specifically to work with the LBL-designed SVX chip. It is typical of systems using a master sequencer module to direct the trigger and readout cycles of the sparse data source and to push data into a digitization and storage module. (orig.)

  20. Comparison of specific production performances by two crystalline silicon PV systems

    Directory of Open Access Journals (Sweden)

    Martin Fajman

    2013-01-01

    Full Text Available A comparison of two independent photovoltaic (PV systems located close to each other on the south of the Czech Moravian Highland was accomplished. Due to differences in installation parameters; reference quantities were used to calculate transformed data sets for specific production performances comparison. Differences in monthly and annually daily production were performed by t-test.According to obtained results, it was concluded that annually mean daily productions per 1 kWp of installed capacity and per 1 m2 of active area of the panels are significantly better by single crystal silicon installation in tracking system than by stable installation of a different technology of single crystal silicon. However, comparing this performance per 1 m2 of occupied land by studied power-plants the stable installation performed higher production rates on daily mean basis in majority of months of the year 2010 as well as by annually mean daily production.

  1. A Medipix2-based imaging system for digital mammography with silicon pixel detectors

    CERN Document Server

    Bisogni, M G; Fantacci, M E; Mettivier, G; Montesi, M C; Novelli, M; Quattrocchi, M; Rosso, V; Russo, P; Stefanini, A

    2004-01-01

    In this paper we present the first tests of a digital imaging system based on a silicon pixel detector bump-bonded to an integrated circuit operating in single photon counting mode. The X-rays sensor is a 300 mu m thick silicon, 14 by 14 mm/sup 2/, upon which a matrix of 256 * 256 pixels has been built. The read-out chip, named MEDIPIX2, has been developed at CERN within the MEDIPIX2 Collaboration and it is composed by a matrix of 256 * 256 cells, 55 * 55 mu m/sup 2/. The spatial resolution properties of the system have been assessed by measuring the square wave resolution function (SWRF) and first images of a standard mammographic phantom were acquired using a radiographic tube in the clinical irradiation condition. (5 refs).

  2. Biological responses of T cells encapsulated with polyelectrolyte-coated gold nanorods and their cellular activities in a co-culture system

    Science.gov (United States)

    Wattanakull, Porntida; Killingsworth, Murray C.; Pissuwan, Dakrong

    2017-11-01

    Currently, human T cell therapy is of considerable scientific interest. In addition, cell encapsulation has become an attractive approach in biomedical applications. Here, we propose an innovative technique of single-cell encapsulation of human T cells using polyelectrolytes combined with gold nanorods. We have demonstrated encapsulation of human Jurkat T cells with poly(sodium 4-styrenesulfonate) (PSS)-coated gold nanorods (PSS-GNRs). Other forms of encapsulation, using polyelectrolytes without GNRs, were also performed. After Jurkat T cells were encapsulated with poly(allylamine hydrochloride) (PAH) and/or PSS-GNRs or PSS, most cells survived and could proliferate. Jurkat T cells encapsulated with a double layer of PSS-GNR/PAH (PSS-GNR/PAH@Jurkat) showed the highest rate of cell proliferation when compared to 24-h encapsulated cells. With the exception of IL-6, no significant induction of inflammatory cytokines (IL-2, IL-1β, and TNF-α) was observed. Interestingly, when encapsulated cells were co-cultured with THP-1 macrophages, co-cultures exhibited TNF-α production enhancement. However, the co-culture of THP-1 macrophage and PSS-GNR/PAH@Jurkat or PSS/PAH@Jurkat did not enhance TNF-α production. No significant inductions of IL-2, IL-1β, and IL-6 were detected. These data provide promising results, demonstrating the potential use of encapsulated PSS-GNR/PAH@Jurkat to provide a more inert T cell population for immunotherapy application and other biomedical applications.

  3. Review of encapsulation technologies

    International Nuclear Information System (INIS)

    Shaulis, L.

    1996-09-01

    The use of encapsulation technology to produce a compliant waste form is an outgrowth from existing polymer industry technology and applications. During the past 12 years, the Department of Energy (DOE) has been researching the use of this technology to treat mixed wastes (i.e., containing hazardous and radioactive wastes). The two primary encapsulation techniques are microencapsulation and macroencapsulation. Microencapsulation is the thorough mixing of a binding agent with a powdered waste, such as incinerator ash. Macroencapsulation coats the surface of bulk wastes, such as lead debris. Cement, modified cement, and polyethylene are the binding agents which have been researched the most. Cement and modified cement have been the most commonly used binding agents to date. However, recent research conducted by DOE laboratories have shown that polyethylene is more durable and cost effective than cements. The compressive strength, leachability, resistance to chemical degradation, etc., of polyethylene is significantly greater than that of cement and modified cement. Because higher waste loads can be used with polyethylene encapsulant, the total cost of polyethylene encapsulation is significantly less costly than cement treatment. The only research lacking in the assessment of polyethylene encapsulation treatment for mixed wastes is pilot and full-scale testing with actual waste materials. To date, only simulated wastes have been tested. The Rocky Flats Environmental Technology Site had planned to conduct pilot studies using actual wastes during 1996. This experiment should provide similar results to the previous tests that used simulated wastes. If this hypothesis is validated as anticipated, it will be clear that polyethylene encapsulation should be pursued by DOE to produce compliant waste forms

  4. Flat-plate solar array project. Volume 7: Module encapsulation

    Science.gov (United States)

    Cuddihy, E.; Coulbert, C.; Gupta, A.; Liang, R.

    1986-01-01

    The objective of the Encapsulation Task was to develop, demonstrate, and qualify photovoltaic (PV) module encapsulation systems that would provide 20 year (later decreased to 30 year) life expectancies in terrestrial environments, and which would be compatible with the cost and performance goals of the Flat-Plate Solar Array (FSA) Project. The scope of the Encapsulation Task included the identification, development, and evaluation of material systems and configurations required to support and protect the optically and electrically active solar cell circuit components in the PV module operating environment. Encapsulation material technologies summarized include the development of low cost ultraviolet protection techniques, stable low cost pottants, soiling resistant coatings, electrical isolation criteria, processes for optimum interface bonding, and analytical and experimental tools for evaluating the long term durability and structural adequacy of encapsulated modules. Field testing, accelerated stress testing, and design studies have demonstrated that encapsulation materials, processes, and configurations are available that meet the FSA cost and performance goals.

  5. Study of modified two incisions silicone oil removal with a 23G transconjunctival sutureless vitrectomy system

    Directory of Open Access Journals (Sweden)

    Hai-Jun Yang

    2015-01-01

    Full Text Available AIM:To evaluate the efficacy and safety of silicone oil removal with a 23G transconjunctival sutureless vitrectomy system linked disposable transfusion tube and self-made suction tip. METHODS: The suction tip was made with a 23G infusion tube be cut from the end of the 5mm. It was used to connect the disposable transfusion tube and 23G puncture cannula. The disposable transfusion tube which was cut from the end of the MaiFei's pipe was connected with the effusion box of the vitreous cutter. Intraocular silicone oil was proactive suction and removed through two incisions on pars plana ciliaris with the vitreous cutter suction system. RESULTS: Only 13 cases(9.8%need suture puncture ports in 132 cases in the operation. Operation time was 7-28min. The average operation time was 15.1± 6.2min. In early postoperative, there were 107 cases(81.1%appeared lower intraocular pressure(CONCLUSION: The surgery that silicone oil is removed through two incisions with a 23G transconjunctival sutureless vitrectomy system linked disposable transfusion tube and self-made suction tip has the advantages of safe, effective, fast, economic, and it is worthy of popularization and application in clinical.

  6. LabVIEW-based control and acquisition system for the dosimetric characterization of a silicon strip detector.

    Science.gov (United States)

    Ovejero, M C; Pérez Vega-Leal, A; Gallardo, M I; Espino, J M; Selva, A; Cortés-Giraldo, M A; Arráns, R

    2017-02-01

    The aim of this work is to present a new data acquisition, control, and analysis software system written in LabVIEW. This system has been designed to obtain the dosimetry of a silicon strip detector in polyethylene. It allows the full automation of the experiments and data analysis required for the dosimetric characterization of silicon detectors. It becomes a useful tool that can be applied in the daily routine check of a beam accelerator.

  7. Micromagnetic and structural investigations on a ferromagnetic nanocomposite system in porous silicon

    International Nuclear Information System (INIS)

    Granitzer, P.; Rumpf, K.; Krenn, H.; Poelt, P.; Reichmann, A.

    2005-01-01

    Full text: Ni-nanowires, perpendicularly embedded to the surface of a Si-template are fabricated in a low-cost, only two-step electrochemical process. In the first step mesoporous silicon with highly oriented pores is produced. The electrochemical parameters for this procedure have to be chosen in a very small regime. This sKEXleton with a homogeneous spatial distribution of the pores is filled with a ferromagnetic material in a second electrochemical step. The selforganized nanowire array is characterized structurally by SEM and EDXS as well as magnetically by SQUID-magnetometry. Magnetization measurements are used to generate a model for the Ni-loading in the channels. Not only wires with diameters smaller than the Bloch-wall thickness and a length between 10 μm and 30 μm are present but also particles in the size up to 200 nm are existent. This nanocomposite system shows a peculiar two-fold magnetic switching characteristic. The first switching is in the low field regime (∼ 500 Oe) and the second one at high fields of a few Tesla. The magnetization reversal is treated in terms of an analytic formulation. The second switching field which occurs as breakdown of the magnetization can be influenced by temperature control and different loading conditions. This promising nanocomposite system is not only interesting in basic research but gives rise to a lot of silicon based applications liKEX magnetic field sensors. Due to rather long spin-relaxation in silicon the needles could be used for spin-injection into c-silicon and therefore it is also an interesting system for spintronics. (author)

  8. Material development in the SI sub 3 N sub 4 system using glass encapsulated Hip'ing

    Energy Technology Data Exchange (ETDEWEB)

    Corbin, N.D.; Sundberg, G.J.; Siebein, K.N.; Willkens, C.A.; Pujari, V.K.; Rossi, G.A.; Hansen, J.S.; Chang, C.L.; Hammarstrom, J.L.

    1992-04-01

    This report covers a two-year program to develop fully dense Si{sub 3}N{sub 4} matrix SiC whisker composites with enhanced properties over monolithic Si{sub 3}N{sub 4} materials. The primary goal was to develop a composite with a fracture toughness > 10 MPa{radical}m, capable of using high pressure glass encapsulated HIP'ing. Coating methods were developed to apply thin (<150nm) stoichiometric BN layers to SiC whiskers and also to apply a dual coating of SiC over carbon to the whiskers. Fracture toughness of the composites was determined to increase as the quantity of whiskers (or elongated grains) with their axis perpendicular to the crack plane increased. Of the interface compositions evaluated in this effort, carbon was determined to be the most effective for increasing toughness. The highest toughnesses (6.8--7.0 MPa{radical}m) were obtained with uniaxially aligned carbon coated whiskers. There was no evidence of the carbon coating compromising the oxidation resistance of the composites at 1370{degree}C.

  9. Design of a basic angle monitoring system in Silicon Carbide

    NARCIS (Netherlands)

    Veggel, van A.A.; Rosielle, P.C.J.N.; Nijmeijer, H.; Wielders, A.A.; Vink, H.J.P.

    2005-01-01

    Due to the 10 microarcsecond accuracy, with which GAIA will measure the positions of stars using 2 astrometric telescopes, stability requirements on the payload module are extremely stringent. In order to achieve the required 10 microarcsecond accuracy, a metrology system could be installed on the

  10. Study of low-mass readout cables for the CBM Silicon Tracking System

    Energy Technology Data Exchange (ETDEWEB)

    Singla, Minni [Goethe Univ. Frankfurt am Main (Germany); GSI, Darmstadt (Germany); Collaboration: CBM-Collaboration

    2013-07-01

    The study of thin multi-line readout cables will be reported. The application is the Silicon Tracking System (STS) of the fixed-target heavy-ion experiment Compressed Baryonic Matter (CBM), under design at the forthcoming accelerator centre FAIR in Germany. These cables will bridge the distance between the microstrip sensors and the signal processing electronics placed at the periphery of the silicon tracking stations. Finite element simulations (using the TCAD package RAPHAEL) have been used to optimize the cables towards minimum possible Equivalent Noise Charge (ENC). Various trace geometries and trace materials have been explored. SPICE modelling has been implemented in Sentaurus Device to study the transmission loss in the cables. The simulations have been validated with measurements. Charge loss in cables of different lengths was determined by injecting charge pulses of known amplitude. An optimized cable design is reported yielding minimum ENC, material budget and transmission loss.

  11. A Forward Silicon Strip System for the ATLAS HL-LHC Upgrade

    CERN Document Server

    Wonsak, S; The ATLAS collaboration

    2012-01-01

    The LHC is successfully accumulating luminosity at a centre-of-mass energy of 8 TeV this year. At the same time, plans are rapidly progressing for a series of upgrades, culminating roughly eight years from now in the High Luminosity LHC (HL-LHC) project. The HL-LHC is expected to deliver approximately five times the LHC nominal instantaneous luminosity, resulting in a total integrated luminosity of around 3000 fb-1 by 2030. The ATLAS experiment has a rather well advanced plan to build and install a completely new Inner Tracker (IT) system entirely based on silicon detectors by 2020. This new IT will be made from several pixel and strip layers. The silicon strip detector system will consist of single-sided p-type detectors with five barrel layers and six endcap (EC) disks on each forward side. Each disk will consist of 32 trapezoidal objects dubbed “petals”, with all services (cooling, read-out, command lines, LV and HV power) integrated into the petal. Each petal will contain 18 silicon sensors grouped in...

  12. Subcutaneous encapsulated fat necrosis

    DEFF Research Database (Denmark)

    Aydin, Dogu; Berg, Jais O

    2016-01-01

    We have described subcutaneous encapsulated fat necrosis, which is benign, usually asymptomatic and underreported. Images have only been published on two earlier occasions, in which the necrotic nodules appear "pearly" than the cloudy yellow surface in present case. The presented image may help...

  13. Performance of the ALIBAVA portable readout system with irradiated and non-irradiated microstrip silicon sensors

    International Nuclear Information System (INIS)

    Marco-Hernadez, R.

    2009-01-01

    A readout system for microstrip silicon sensors has been developed as a result of collaboration among the University of Liverpool, the CNM of Barcelona and the IFIC of Valencia. The name of this collaboration is ALIBAVA and it is integrated in the RD50 Collaboration. This system is able to measure the collected charge in one or two microstrip silicon sensors by reading out all the channels of the sensor(s), up to 256, as an analogue measurement. The system uses two Beetle chips to read out the detector(s). The Beetle chip is an analogue pipelined readout chip used in the LHCb experiment. The system can operate either with non-irradiated and irradiated sensors as well as with n-type and p-type microstrip silicon sensors. Heavily irradiated sensors will be used at the SLHC, so this system is being to research the performance of microstrip silicon sensors in conditions as similar as possible to the SLHC operating conditions. The system has two main parts: a hardware part and a software part. The hardware part acquires the sensor signals either from external trigger inputs, in case of a radioactive source setup is used, or from a synchronised trigger output generated by the system, if a laser setup is used. This acquired data is sent by USB to be stored in a PC for a further processing. The hardware is a dual board based system. The daughterboard is a small board intended for containing two Beetle readout chips as well as fan-ins and detector support to interface the sensors. The motherboard is intended to process the data, to control the whole hardware and to communicate with the software by USB. The software controls the system and processes the data acquired from the sensors in order to store it in an adequate format file. The main characteristics of the system will be described. Results of measurements acquired with n-type and p-type irradiated and non-irradiated detectors using both the laser and the radioactive source setup will be also presented and discussed

  14. Assembly procedure for the silicon pixel ladder for PHENIX silicon vertex tracker

    International Nuclear Information System (INIS)

    Onuki, Y.; Akiba, Y.; En'yo, H.; Fujiwara, K.; Haki, Y.; Hashimoto, K.; Ichimiya, R.; Kasai, M.; Kawashima, M.; Kurita, K.; Kurosawa, M.; Mannel, E.J.; Nakano, K.; Pak, R.; Sekimoto, M.; Sondheim, W.E.; Taketani, A.; Togawa, M.; Yamamoto, Y.

    2009-01-01

    The silicon vertex tracker (VTX) will be installed in the summer of 2010 to enhance the physics capabilities of the Pioneering High Energy Nuclear Interaction eXperiment (PHENIX) experiment at Brookhaven National Laboratory. The VTX consists of two types of silicon detectors: a pixel detector and a strip detector. The pixel detector consists of 30 pixel ladders placed on the two inner cylindrical layers of the VTX. The ladders are required to be assembled with high precision, however, they should be assembled in both cost and time efficient manner. We have developed an assembly bench for the ladder with several assembly fixtures and a quality assurance (Q/A) system using a 3D measurement machine. We have also developed an assembly procedure for the ladder, including a method for dispensing adhesive uniformly and encapsulation of bonding wires. The developed procedures were adopted in the assembly of the first pixel ladder and satisfy the requirements.

  15. Encapsulation of iron nanoparticles in alginate biopolymer for trichloroethylene remediation

    International Nuclear Information System (INIS)

    Bezbaruah, Achintya N.; Shanbhogue, Sai Sharanya; Simsek, Senay; Khan, Eakalak

    2011-01-01

    Nanoscale zero-valent iron (NZVI) particles (10–90 nm) were encapsulated in biodegradable calcium-alginate capsules for the first time for application in environmental remediation. Encapsulation is expected to offers distinct advances over entrapment. Trichloroethylene (TCE) degradation was 89–91% in 2 h, and the reaction followed pseudo first order kinetics for encapsulated NZVI systems with an observed reaction rate constant (k obs ) of 1.92–3.23 × 10 −2 min −1 and a surface normalized reaction rate constant (k sa ) of 1.02–1.72 × 10 −3 L m −2 min −1 . TCE degradation reaction rates for encapsulated and bare NZVI were similar indicating no adverse affects of encapsulation on degradation kinetics. The shelf-life of encapsulated NZVI was found to be four months with little decrease in TCE removal efficiency.

  16. Virtual design and optimization studies for industrial silicon microphones applying tailored system-level modeling

    Science.gov (United States)

    Kuenzig, Thomas; Dehé, Alfons; Krumbein, Ulrich; Schrag, Gabriele

    2018-05-01

    Maxing out the technological limits in order to satisfy the customers’ demands and obtain the best performance of micro-devices and-systems is a challenge of today’s manufacturers. Dedicated system simulation is key to investigate the potential of device and system concepts in order to identify the best design w.r.t. the given requirements. We present a tailored, physics-based system-level modeling approach combining lumped with distributed models that provides detailed insight into the device and system operation at low computational expense. The resulting transparent, scalable (i.e. reusable) and modularly composed models explicitly contain the physical dependency on all relevant parameters, thus being well suited for dedicated investigation and optimization of MEMS devices and systems. This is demonstrated for an industrial capacitive silicon microphone. The performance of such microphones is determined by distributed effects like viscous damping and inhomogeneous capacitance variation across the membrane as well as by system-level phenomena like package-induced acoustic effects and the impact of the electronic circuitry for biasing and read-out. The here presented model covers all relevant figures of merit and, thus, enables to evaluate the optimization potential of silicon microphones towards high fidelity applications. This work was carried out at the Technical University of Munich, Chair for Physics of Electrotechnology. Thomas Kuenzig is now with Infineon Technologies AG, Neubiberg.

  17. An improved detector response simulation for the CBM silicon tracking system

    Energy Technology Data Exchange (ETDEWEB)

    Malygina, Hanna [Goethe University, Frankfurt (Germany); Friese, Volker [GSI, Darmstadt (Germany); Collaboration: CBM-Collaboration

    2015-07-01

    The Compressed Baryonic Matter experiment(CBM) at FAIR is designed to explore the QCD phase diagram in the region of high net-baryon densities. The central detector component the Silicon Tracking System (STS) is build from double-sided micro-strip sensors. To achieve realistic simulations the response of the silicon strip sensors should be precisely included in the digitizer which simulates a complete chain of physical processes caused by charged particles traversing the detector, from charge creation in silicon to a digital output signal. The new version of the STS digitizer comprises in addition non-uniform energy loss distributions (according to the Urban theory), thermal diffusion and charge redistribution over the read-out channels due to interstrip capacitances. The improved response simulation was tested with parameters reproducing the anticipated running conditions of the CBM experiment. Two different method for cluster finding were used. The results for hit position residuals, cluster size distribution, as well as for some other parameters of reconstruction quality are presented. The achieved advance is assessed by a comparison with the previous, simpler version of the STS detector response simulation.

  18. Development of radiation hard microstrip detectors for the CBM silicon tracking system

    Energy Technology Data Exchange (ETDEWEB)

    Chatterji, Sudeep [GSI, Darmstadt (Germany)

    2010-07-01

    Radiation damage in Silicon microstrip detectors is of the one main concerns for the development of the Silicon Tracking System (STS) in the planned Compressed Baryonic Matter (CBM) experiment at FAIR. The STS will consist of Double Sided Silicon Strip Detectors (DSSD) having pitch around 60 {mu}m, width 20 {mu}m, stereo angle of {+-}7.5{sup 0} on n and p sides with double metallization on either side making it challenging to fabricate.We are using 3-dimensional TCAD simulation tools from SYNOPSYS to carry out process (using Sentaurus Process) and device (using Sentaurus Device) simulations.We have simulated the impact of radiation damage in DSSDs by changing the effective carrier concentration (N{sub eff}) with fluence using the Hamburg model. The change in minority carrier life time has been taken into account using the Kraners model and the Perugia trap model has been used to simulate the traps. We have also extracted macroscopic parameters like Coupling Capacitance, Interstrip Capacitance (both DC and AC), Interstrip Resistance of DSSDs using Mixed Mode simulation (using SPICE with Sentaurus Device) and studied the variation of these parameters with fluence. The simulation results have been compared to the experimental results. We also simulated transients by passing a Heavy Ion through a DSSD and studied the charge collection performance.

  19. Encapsulation and Nano-Encapsulation of Papain Active Sites to Enhance Radiolityc Stability and Decrease Toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Lugão, A. B.; Varca, G. H.C.; Mathor, M. B.; Santos Lopes, P.; Rogero, M. S.S.; Rogero, J.R., E-mail: ablugao@ipen.br [Comissão Nacional de Energia Nuclear (CNEN), Instituto de Pesquisas Energeticas e Nucleares (IPEN), Av. Prof. Lineu Prestes, 2242 Cidade Universitaria, 05508-000 Sao Paulo (Brazil)

    2010-07-01

    Papain is used as an ingredient in various enzymatic debridement preparations. Those paste-like preparations are based on water solution and usually are sterilized by radiation. As a consequence, there is a major decrease in papain activity. Papain containing preparations are used in chronic wounds treatment in order to clean and remove the necrotic tissue. However FDA (2008) is taking an action against such products due to severe adverse events reported in patients submitted to papain treatments. Thus, the main goal of this proposal is to develop encapsulated papain containing membranes based on hydrogels and silicone rubber in an attempt to achieve a controllable distribution of size and delivery profile, a toxicity reduction and provide stability towards radiation processing through molecular encapsulation with β-cyclodextrin, which may also provide protection to the enzyme against radiation induced radiolysis. (author)

  20. Encapsulation and Nano-Encapsulation of Papain Active Sites to Enhance Radiolityc Stability and Decrease Toxicity

    International Nuclear Information System (INIS)

    Lugão, A.B.; Varca, G.H.C.; Mathor, M.B.; Santos Lopes, P.; Rogero, M.S.S.; Rogero, J.R.

    2010-01-01

    Papain is used as an ingredient in various enzymatic debridement preparations. Those paste-like preparations are based on water solution and usually are sterilized by radiation. As a consequence, there is a major decrease in papain activity. Papain containing preparations are used in chronic wounds treatment in order to clean and remove the necrotic tissue. However FDA (2008) is taking an action against such products due to severe adverse events reported in patients submitted to papain treatments. Thus, the main goal of this proposal is to develop encapsulated papain containing membranes based on hydrogels and silicone rubber in an attempt to achieve a controllable distribution of size and delivery profile, a toxicity reduction and provide stability towards radiation processing through molecular encapsulation with β-cyclodextrin, which may also provide protection to the enzyme against radiation induced radiolysis. (author)

  1. LHCb: The LHCb Silicon Tracker - Control system specific tools and challenges

    CERN Multimedia

    Saornil Gamarra, S

    2013-01-01

    The experiment control system of the LHCb experiment is continuously evolving and improving. The guidelines and structure initially defined are kept, and more common tools are made available to all sub-detectors. Although the main system control is mostly integrated and actions are executed in common for the whole LHCb experiment, there is some degree of freedom for each sub-system to implement the control system using these tools or by creating new ones. The implementation of the LHCb Silicon Tracker control system was extremely disorganized and with little documentation. This was due to either lack of time and manpower, and/or to limited experience and specifications. Despite this, the Silicon Tracker control system has behaved well during the first LHC run. It has continuously evolved since the start of operation and been adapted to the needs of operators with very different degrees of expertise. However, improvements and corrections have been made on a best effort basis due to time constraints placed by t...

  2. In-situ formation of nanoparticles within a silicon-based matrix

    Science.gov (United States)

    Thoma, Steven G [Albuquerque, NM; Wilcoxon, Jess P [Albuquerque, NM; Abrams, Billie L [Albuquerque, NM

    2008-06-10

    A method for encapsulating nanoparticles with an encapsulating matrix that minimizes aggregation and maintains favorable properties of the nanoparticles. The matrix comprises silicon-based network-forming compounds such as ormosils and polysiloxanes. The nanoparticles are synthesized from precursors directly within the silicon-based matrix.

  3. Nondestructive Assay Options for Spent Fuel Encapsulation

    Energy Technology Data Exchange (ETDEWEB)

    Tobin, Stephen J. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Jansson, Peter [Uppsala Univ. (Sweden)

    2014-10-02

    This report describes the role that nondestructive assay (NDA) techniques and systems of NDA techniques may have in the context of an encapsulation and deep geological repository. The potential NDA needs of an encapsulation and repository facility include safeguards, heat content, and criticality. Some discussion of the facility needs is given, with the majority of the report concentrating on the capability and characteristics of individual NDA instruments and techniques currently available or under development. Particular emphasis is given to how the NDA techniques can be used to determine the heat production of an assembly, as well as meet the dual safeguards needs of 1) determining the declared parameters of initial enrichment, burn-up, and cooling time and 2) detecting defects (total, partial, and bias). The report concludes with the recommendation of three integrated systems that might meet the combined NDA needs of the encapsulation/repository facility.

  4. Effects of pore forming agents of potassium bicarbonate and drug loading method against dissolution mechanisms of amoxicillin drugs encapsulated in hydrogel full-Ipn chitosan-poly(N-vinylcaprolactam) as a floating drug delivery system

    Science.gov (United States)

    Aini, Nurul; Rahayu, Dyah Utami Cahyaning; Budianto, Emil

    2018-04-01

    The limitation of amoxicillin trihydrate in the treatment of H. pylori bacteria is relatively short retention time in the stomach. The FDDS (Floating Drug Delivery System) amoxicillin trihydrate into a chitosan-poly(N-vinylcaprolactam) full-Ipn hydrogel matrix using a pore-forming agent KHCO3 is expected to overcome these limitations. The pore-forming agent to be used is 15% KHCO3 compound. Chemical kinetics approach is performed to determine the dissolution mechanism of amoxicillin trihydrate from K-PNVCL hydrogel in vitro on gastric pH and characterization using SEM performed to confirm the dissolution mechanism. Hydrogels with the addition of pore-forming agents will be loading in situ loading and post loading. Fourier Transform Infra Red (FTIR) spectroscopy was used to characterize K-PNVCL and UV-Vis hydrogels used to calculate the efficiency of encapsulation and drug dissolution rate in K-PNVCL hydrogel. Hydrogel K-PNVCL / KHCO3 that encapsulated by in situ loading method resulted in an encapsulation efficiency of 93.5% and dissolution of 93.4%. While the Hydrogel K-PNVCL / KHCO3 which is drug encapsulation resulted in an encapsulation efficiency of 87.2% with dissolution of 81.5%. Chemical kinetics approach to in situ encapsulation of loading and post loading shows the dissolution mechanism occurring in the K-PNVCL / KHCO3 hydrogel matrix occurs by diffusion. Observation using optical microscope and SEM showed the mechanism of drug dissolution in Hydrogel K-PNVCL occurred by diffusion.

  5. Arsenic implantation into polycrystalline silicon and diffusion to silicon substrate

    International Nuclear Information System (INIS)

    Tsukamoto, K.; Akasaka, Y.; Horie, K.

    1977-01-01

    Arsenic implantation into polycrystalline silicon and drive-in diffusion to silicon substrate have been investigated by MeV He + backscattering analysis and also by electrical measurements. The range distributions of arsenic implanted into polycrystalline silicon are well fitted to Gaussian distributions over the energy range 60--350 keV. The measured values of R/sub P/ and ΔR/sub P/ are about 10 and 20% larger than the theoretical predictions, respectively. The effective diffusion coefficient of arsenic implanted into polycrystalline silicon is expressed as D=0.63 exp[(-3.22 eV/kT)] and is independent of the arsenic concentration. The drive-in diffusion of arsenic from the implanted polycrystalline silicon layer into the silicon substrate is significantly affected by the diffusion atmosphere. In the N 2 atmosphere, a considerable amount of arsenic atoms diffuses outward to the ambient. The outdiffusion can be suppressed by encapsulation with Si 3 N 4 . In the oxidizing atmosphere, arsenic atoms are driven inward by growing SiO 2 due to the segregation between SiO 2 and polycrystalline silicon, and consequently the drive-in diffusion of arsenic is enhanced. At the interface between the polycrystalline silicon layer and the silicon substrate, arsenic atoms are likely to segregate at the polycrystalline silicon side

  6. Encapsulation Efficiency, Oscillatory Rheometry

    Directory of Open Access Journals (Sweden)

    Z. Mohammad Hassani

    2014-01-01

    Full Text Available Nanoliposomes are one of the most important polar lipid-based nanocarriers which can be used for encapsulation of both hydrophilic and hydrophobic active compounds. In this research, nanoliposomes based on lecithin-polyethylene glycol-gamma oryzanol were prepared by using a modified thermal method. Only one melting peak in DSC curve of gamma oryzanol bearing liposomes was observed which could be attributed to co-crystallization of both compounds. The addition of gamma oryzanol, caused to reduce the melting point of 5% (w/v lecithin-based liposome from 207°C to 163.2°C. At high level of lecithin, increasing of liposome particle size (storage at 4°C for two months was more obvious and particle size increased from 61 and 113 to 283 and 384 nanometers, respectively. The encapsulation efficiency of gamma oryzanol increased from 60% to 84.3% with increasing lecithin content. The encapsulation stability of oryzanol in liposome was determined at different concentrations of lecithin 3, 5, 10, 20% (w/v and different storage times (1, 7, 30 and 60 days. In all concentrations, the encapsulation stability slightly decreased during 30 days storage. The scanning electron microscopy (SEM images showed relatively spherical to elliptic particles which indicated to low extent of particles coalescence. The oscillatory rheometry showed that the loss modulus of liposomes were higher than storage modulus and more liquid-like behavior than solid-like behavior. The samples storage at 25°C for one month, showed higher viscoelastic parameters than those having been stored at 4°C which were attributed to higher membrane fluidity at 25°C and their final coalescence.Nanoliposomes are one of the most important polar lipid based nanocarriers which can be used for encapsulation of both hydrophilic and hydrophobic active compounds. In this research, nanoliposomes based on lecithin-polyethylene glycol-gamma oryzanol were prepared by using modified thermal method. Only one

  7. Considerations for successful transplantation of encapsulated pancreatic islets

    NARCIS (Netherlands)

    de Vos, P; Hamel, AF; Tatarkiewicz, K

    Encapsulation of pancreatic islets allows for transplantion in the absence of immunosuppression. The technology is based on the principle that transplanted tissue is protected for the host immune system by an artificial membrane. Encapsulation offers a solution to the shortage of donors in clinical

  8. Mechanical Robustness and Hermeticity Monitoring for MEMS Thin Film Encapsulation

    NARCIS (Netherlands)

    Santagata, F.

    2011-01-01

    Many Micro-Electro-Mechanical-Systems (MEMS) require encapsulation, to prevent delicate sensor structures being exposed to external perturbations such as dust, humidity, touching, and gas pressure. An upcoming and cost-effective way of encapsulation is zero-level packaging or thin-film

  9. A Three-Dimensional Microdisplacement Sensing System Based on MEMS Bulk-Silicon Technology

    Directory of Open Access Journals (Sweden)

    Junjie Wu

    2014-10-01

    Full Text Available For the dimensional measurement and characterization of microsized and nanosized components, a three-dimensional microdisplacement sensing system was developed using the piezoresistive effect in silicon. The sensor was fabricated using microelectromechanical system bulk-silicon technology, and it was validated using the finite element method. A precise data acquisition circuit with an accuracy of 20 μV was designed to obtain weak voltage signals. By calibration, the sensing system was shown to have a sensitivity of 17.29 mV/μm and 4.59 mV/μm in the axial and lateral directions, respectively; the nonlinearity in these directions was 0.8% and 1.0% full scale, respectively. A full range of 4.6 μm was achieved in the axial direction. Results of a resolution test indicated that the sensing system had a resolution of 5 nm in the axial direction and 10 nm in the lateral direction.

  10. Environmental Life Cycle Inventory of Crystalline Silicon Photovoltaic System Production. Status 2005-2006 (Excel File)

    International Nuclear Information System (INIS)

    De Wild - Scholten, M.J.; Alsema, E.A.

    2007-03-01

    The authors have assembled this LCI data set to the best of their knowledge and in their opinion it gives a reliable representation of the crystalline silicon module production technology in Western-Europe in the year 2005/2006 and Balance-of-System components of the year 2006. However, most of the data were provided to them by the companies that helped them. Although they have cross-checked the data from different sources they cannot guarantee that it does not contain any errors. Therefore they cannot accept any responsibility for the use of these data

  11. Microstrip silicon detectors of the monitoring and triggering systems in the E-161 experiment

    International Nuclear Information System (INIS)

    Bogolyubskij, M.Yu.; Kurchaninov, L.L.; Moiseev, A.M.; Semenov, P.A.; Leflat, A.K.; Sekhniaidze, G.G.

    1991-01-01

    A monitoring and triggering system based on microstrip silicon detectors (MSD) and fast-response low-noise electronics with the number of the readout channels equal to 896, is described. The PMS noise is ENC=25x10 3 e - with the signal integration time of 50 ns. The probability of registering a noise pulse by one channel during data readout cycle is not more than 2.5x10 -6 . The time resolution (FWHM) is (16±3) ns. 17 refs.; 7 figs

  12. Neutron irradiation results for the LHCb silicon tracker data readout system components

    CERN Document Server

    Vollhardt, A

    2003-01-01

    This note reports irradiation data for different components of the LHCb Silicon Tracker data readout system, which will be exposed to neutron fluences due to their location in the readout link service box on the tracking station frame. The components were part of a neutron irradiation campaign in April 2003 at the Prospero reactor at CEA Valduc (France) and were exposed to fluences 5 to 100 times higher than the expected fluences at the experiment. For all tested components, minor or no influence on device performance was measured. We therefore consider the tested components to be compatible with the expected neutron fluences at the foreseen locations in the LHCb experiment.

  13. Numerical modelling of transdermal delivery from matrix systems: parametric study and experimental validation with silicone matrices.

    Science.gov (United States)

    Snorradóttir, Bergthóra S; Jónsdóttir, Fjóla; Sigurdsson, Sven Th; Másson, Már

    2014-08-01

    A model is presented for transdermal drug delivery from single-layered silicone matrix systems. The work is based on our previous results that, in particular, extend the well-known Higuchi model. Recently, we have introduced a numerical transient model describing matrix systems where the drug dissolution can be non-instantaneous. Furthermore, our model can describe complex interactions within a multi-layered matrix and the matrix to skin boundary. The power of the modelling approach presented here is further illustrated by allowing the possibility of a donor solution. The model is validated by a comparison with experimental data, as well as validating the parameter values against each other, using various configurations with donor solution, silicone matrix and skin. Our results show that the model is a good approximation to real multi-layered delivery systems. The model offers the ability of comparing drug release for ibuprofen and diclofenac, which cannot be analysed by the Higuchi model because the dissolution in the latter case turns out to be limited. The experiments and numerical model outlined in this study could also be adjusted to more general formulations, which enhances the utility of the numerical model as a design tool for the development of drug-loaded matrices for trans-membrane and transdermal delivery. © 2014 Wiley Periodicals, Inc. and the American Pharmacists Association.

  14. Fabrication and Analysis of Tapered Tip Silicon Microneedles for MEMS based Drug Delivery System

    Directory of Open Access Journals (Sweden)

    Muhammad Waseem Ashraf

    2010-11-01

    Full Text Available In this paper, a novel design of transdermal drug delivery (TDD system is presented. The proposed system consists of controlled electronic circuit and microelectromechanical system (MEMS based devices like microneedles, micropump, flow sensor, and blood pressure sensor. The aim of this project is to develop a system that can eliminate the limitations associated with oral therapy. In this phase tapered tip silicon microneedles have been fabricated using inductively coupled plasma (ICP etching technology. Using ANSYS, simulation of microneedles has been conducted before the fabrication process to test the design suitability for TDD. More over multifield analysis of reservoir integrated with microneedle array using piezoelectric actuator has also been performed. The effects of frequency and voltage on actuator and fluid flow rate through 6×6 microneedle array have been investigated. This work provides envisage data to design suitable devices for TDD.

  15. Design and operation of grid-interactive thin-film silicon PV systems

    Science.gov (United States)

    Marion, Bill; Atmaram, Gobind; Lashway, Clin; Strachan, John W.

    Results are described from the operation of 11 thin-film amorphous silicon photovoltaic systems at three test facilities: the Florida Solar Energy Center, the New Mexico Solar Energy Institute, and Sandia National Laboratories. Commercially available modules from four US manufacturers are used in these systems, with array sizes from 133 to 750 W peak. Measured array efficiencies are from 3.1 to 4.8 percent. Except for one manufacturer, array peak power is in agreement with the calculated design ratings. For certain grid-connected systems, nonoptimal operation exists because the array peak power voltage is below the lower voltage limit of the power conditioning system. Reliability problems are found in two manufacturers' modules when shorts to ground and terminal corrosion occur. Array leakage current data are presented.

  16. Silicon synaptic transistor for hardware-based spiking neural network and neuromorphic system

    Science.gov (United States)

    Kim, Hyungjin; Hwang, Sungmin; Park, Jungjin; Park, Byung-Gook

    2017-10-01

    Brain-inspired neuromorphic systems have attracted much attention as new computing paradigms for power-efficient computation. Here, we report a silicon synaptic transistor with two electrically independent gates to realize a hardware-based neural network system without any switching components. The spike-timing dependent plasticity characteristics of the synaptic devices are measured and analyzed. With the help of the device model based on the measured data, the pattern recognition capability of the hardware-based spiking neural network systems is demonstrated using the modified national institute of standards and technology handwritten dataset. By comparing systems with and without inhibitory synapse part, it is confirmed that the inhibitory synapse part is an essential element in obtaining effective and high pattern classification capability.

  17. Silicon-Film(TM) Solar Cells by a Flexible Manufacturing System: Final Report, 16 April 1998 -- 31 March 2001

    Energy Technology Data Exchange (ETDEWEB)

    Rand, J.

    2002-02-01

    This report describes the overall goal to engineer and develop flexible manufacturing methods and equipment to process Silicon-Film solar cells and modules. Three major thrusts of this three-year effort were to: develop a new larger-area (208 mm x 208 mm) Silicon-Film solar cell, the APx-8; construct and operate a new high-throughput wafer-making system; and develop a 15-MW single-thread manufacturing process. Specific technical accomplishments from this period are: Increase solar cell area by 80%, increase the generation capacity of a Silicon-Film wafer-making system by 350%, use a new in-line HF etch system in solar cell production, design and develop an in-line NaOH etch system, eliminate cassettes in solar cell processing, and design a new family of module products.

  18. Encapsulation methods and dielectric layers for organic electrical devices

    Science.gov (United States)

    Blum, Yigal D; Chu, William Siu-Keung; MacQueen, David Brent; Shi, Yijan

    2013-07-02

    The disclosure provides methods and materials suitable for use as encapsulation barriers and dielectric layers in electronic devices. In one embodiment, for example, there is provided an electroluminescent device or other electronic device with a dielectric layer comprising alternating layers of a silicon-containing bonding material and a ceramic material. The methods provide, for example, electronic devices with increased stability and shelf-life. The invention is useful, for example, in the field of microelectronic devices.

  19. Electromagnetic properties of conducting polymers encapsulated in an insulating matrix

    International Nuclear Information System (INIS)

    Esnouf, Stephane

    1995-01-01

    The aim of this work is to study the electronic properties of conducting polymers encapsulated in zeolite. We studied two kinds of polymers: intrinsic conducting polymers (poly-pyrrole) and pyrolyzed polymers (polyacrylonitrile and poly-furfuryl alcohol). These systems were characterized by electron paramagnetic resonance and microwave conductivity measurements. In the first part, we present the preparation and the characterization of encapsulated poly-pyrrole. Conductivity measurements show that the encapsulated material is insulating, certainly because a strong interaction with the zeolite traps the charge carriers. In the second part, we focus on pyrolyzed encapsulated polyacrylonitrile. This system has a metal-like susceptibility at room temperature and a relatively high microwave conductivity. These results demonstrate the formation during the pyrolysis of extended aromatic clusters. Finally, we study pyrolyzed encapsulated poly-furfuryl alcohol. We show that the only effect of the pyrolysis is to fragment the polymers. We also discuss the spin relaxation and the EPR line broadening. (author) [fr

  20. Development of a Silicon Based Electron Beam Transmission Window for Use in a KrF Excimer Laser System

    International Nuclear Information System (INIS)

    Gentile, C.A.; Fan, H.M.; Hartfield, J.W.; Hawryluk, R.J.; Hegeler, F.; Heitzenroeder, P.J.; Jun, C.H.; Ku, L.P.; LaMarche, P.H.; Myers, M.C.; Parker, J.J.; Parsells, R.F.; Payen, M.; Raftopoulos, S.; Sethian, J.D.

    2002-01-01

    The Princeton Plasma Physics Laboratory (PPPL), in collaboration with the Naval Research Laboratory (NRL), is currently investigating various novel materials (single crystal silicon, , and ) for use as electron-beam transmission windows in a KrF excimer laser system. The primary function of the window is to isolate the active medium (excimer gas) from the excitation mechanism (field-emission diodes). Chosen window geometry must accommodate electron energy transfer greater than 80% (750 keV), while maintaining structural integrity during mechanical load (1.3 to 2.0 atm base pressure differential, approximate 0.5 atm cyclic pressure amplitude, 5 Hz repetition rate) and thermal load across the entire hibachi area (approximate 0.9 W · cm superscript ''-2''). In addition, the window must be chemically resistant to attack by fluorine free-radicals (hydrofluoric acid, secondary). In accordance with these structural, functional, and operational parameters, a 22.4 mm square silicon prototype window, coated with 500 nm thin-film silicon nitride (Si 3 N 4 ), has been fabricated. The window consists of 81 square panes with a thickness of 0.019 mm ± 0.001 mm. Stiffened (orthogonal) sections are 0.065 mm in width and 0.500 mm thick (approximate). Appended drawing (Figure 1) depicts the window configuration. Assessment of silicon (and silicon nitride) material properties and CAD modeling and analysis of the window design suggest that silicon may be a viable solution to inherent parameters and constraints

  1. Confined Li ion migration in the silicon-graphene complex system: An ab initio investigation

    Science.gov (United States)

    Wang, Guoqing; Xu, Bo; Shi, Jing; Lei, Xueling; Ouyang, Chuying

    2018-04-01

    Silicon-Carbon complex systems play an important role in enhancing the performance of Si-based anode materials for Li ion batteries. In this work, the Li migration property of the Silicon-Graphene (Si-Gr) complex systems are investigated by using first-principles calculations. Especially, the effects of graphene coating on the migration of Li ions are discussed in detail. The distance between Si surface and graphene in the Si-Gr system significantly affects the lateral migration of Li ions. With the decrease of the distance from 4.715 to 3.844 Å, the energy barrier of Li ion migration also decreases from 0.115 to 0.067 eV, which are all lower than that of the case without graphene d(0.135 eV). However, smaller distance (3.586 Å) brings the high energy barrier (0.237 eV). Through AIMD calculations, it is found that the graphene coating in the Si-Gr complex system would result in the larger intercalation depths, more uniform distributions, and higher migration coefficients of Li ions. Further calculations of migration coefficients of Li ions at different temperature are used to obtained the activation energy for Li ions migration in the Si-Gr system, which is as low as 0.028 eV. This low activation energy shows that it is easy for Li ions migrating in the Si-Gr system. Our study provided the basically information to understand the migration mechanism of Li ions in Si-C system.

  2. Viability study of porous silicon photonic mirrors as secondary reflectors for solar concentration systems

    Energy Technology Data Exchange (ETDEWEB)

    de la Mora, M.B.; Jaramillo, O.A.; Nava, R.; Tagueena-Martinez, J. [Centro de Investigacion en Energia, Universidad Nacional Autonoma de Mexico, A. P. 34, 62580 Temixco, Morelos (Mexico); del Rio, J.A. [Centro Morelense de Innovacion y Transferencia Tecnologica, CCyTEM Camino Temixco a Emiliano Zapata, Km 0.3, Colonia Emiliano Zapata, 62760 Morelos (Mexico)

    2009-08-15

    In this paper we report the viability of using porous silicon photonic mirrors (PSPM) as secondary reflectors in solar concentration systems. The PSPM were fabricated with nanostructured porous silicon to reflect light from the visible range to the near infrared region (500-2500 nm), although this range could be tuned for specific wavelength applications. Our PSPM are multilayers of two alternated refractive indexes (1.5 and 2.0), where the condition of a quarter wavelength in the optical path was imposed. The PSPM were exposed to high radiation in a solar concentrator equipment. As a result, we observed a significant degradation of the mirrors at an approximated temperature of 900 C. In order to analyze the origin of the degradation of PSPM, we model the samples with a non-linear optical approach and study the effect of a temperature increase. Those theoretical and experimental studies allow us to conclude that the main phenomenon involved in the breakdown of the photonic mirrors is of thermal origin, produced by heterogeneous expansion of each layer. Our next step was to introduce a cooling system into the solar concentrator to keep the mirrors at approximately 70 C, with very good results. As a conclusion we propose the use of PSPM as selective secondary mirrors in solar concentration devices using temperature control to avoid thermal degradation. (author)

  3. Mechanical integration of the detector components for the CBM silicon tracking system

    Energy Technology Data Exchange (ETDEWEB)

    Vasylyev, Oleg; Niebur, Wolfgang [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Darmstadt (Germany); Collaboration: CBM-Collaboration

    2016-07-01

    The Compressed Baryonic Matter experiment (CBM) at FAIR is designed to explore the QCD phase diagram in the region of high net-baryon densities. The central detector component, the Silicon Tracking System (STS) is based on double-sided micro-strip sensors. In order to achieve the physics performance, the detector mechanical structures should be developed taking into account the requirements of the CBM experiments: low material budget, high radiation environment, interaction rates, aperture for the silicon tracking, detector segmentation and mounting precision. A functional plan of the STS and its surrounding structural components is being worked out from which the STS system shape is derived and the power and cooling needs, the connector space requirements, life span of components and installation/repair aspects are determined. The mechanical integration is at the point of finalizing the design stage and moving towards production readiness. This contribution shows the current processing state of the following engineering tasks: construction space definition, carbon ladder shape and manufacturability, beam-pipe feedthrough structure, prototype construction, cable routing and modeling of the electronic components.

  4. An exploration of neuromorphic systems and related design issues/challenges in dark silicon era

    Science.gov (United States)

    Chandaliya, Mudit; Chaturvedi, Nitin; Gurunarayanan, S.

    2018-03-01

    The current microprocessors has shown a remarkable performance and memory capacity improvement since its innovation. However, due to power and thermal limitations, only a fraction of cores can operate at full frequency at any instant of time irrespective of the advantages of new technology generation. This phenomenon of under-utilization of microprocessor is called as dark silicon which leads to distraction in innovative computing. To overcome the limitation of utilization wall, IBM technologies explored and invented neurosynaptic system chips. It has opened a wide scope of research in the field of innovative computing, technology, material sciences, machine learning etc. In this paper, we first reviewed the diverse stages of research that have been influential in the innovation of neurosynaptic architectures. These, architectures focuses on the development of brain-like framework which is efficient enough to execute a broad set of computations in real time while maintaining ultra-low power consumption as well as area considerations in mind. We also reveal the inadvertent challenges and the opportunities of designing neuromorphic systems as presented by the existing technologies in the dark silicon era, which constitute the utmost area of research in future.

  5. A readout system for position sensitive measurements of X-ray using silicon strip detectors

    CERN Document Server

    Dabrowski, W; Grybos, P; Idzik, M; Kudlaty, J

    2000-01-01

    In this paper we describe the development of a readout system for X-ray measurements using silicon strip detectors. The limitation concerning the inherent spatial resolution of silicon strip detectors has been evaluated by Monte Carlo simulation and the results are discussed. The developed readout system is based on the binary readout architecture and consists of two ASICs: RX32 front-end chip comprising 32 channels of preamplifiers, shapers and discriminators, and COUNT32 counter chip comprising 32 20-bit asynchronous counters and the readout logic. This work focuses on the design and performance of the front-end chip. The RX32 chip has been optimised for a low detector capacitance, in the range of 1-3 pF, and high counting rate applications. It can be used with DC coupled detectors allowing the leakage current up to a few nA per strip. For the prototype chip manufactured in a CMOS process all basic parameters have been evaluated by electronic measurements. The noise below 140 el rms has been achieved for a ...

  6. A radiation tolerant fiber-optic readout system for the LHCb Silicon Tracker

    CERN Document Server

    Agari, M; Blouw, J; Hofmann, W; Knöpfle, K T; Löchner, S; Schmelling, M; Schwingenheuer, B; Pugatch, V; Pylypchenko, Y; Bay, A; Carron, B; Fauland, P; Frei, R; Jiménez-Otero, S; Perrin, A; Tran, M T; Van Hunen, J J; Vervink, K; Vollhardt, A; Voss, H; Adeva, B; Esperante-Pereira, D; Lois, C; Vázquez, P; Bernhard, R P; Bernet, R; Gassner, J; Köstner, S; Lehner, F; Needham, M; Steinkamp, O; Straumann, U; Volyanskyy, D; Wenger, A

    2005-01-01

    A fiber-optic readout system has been designed for the LHCb Silicon Tracker to transmit the detector data to the counting room at a distance of 120 m from the detectors. In total, data from over 272000 detector channels have to be transmitted at an average trigger frequency of 1.1 MHz. In the design of the system, special attention was given to its radiation tolerance, as the transmitting section is located close to the beamline and therefore is exposed to moderate particle fluences and ionizing dose during the expected operational life of 10 years. We give a general overview of the readout link scheme and present performance data on its reliability and radiation tolerance obtained from first preseries elements of the system. Poster presented on the 10th European Symposium on Semiconductor Detectors, June 12th â€" June 16th 2005, Wildbad Kreuth, Germany.

  7. Millimeter Wave Imaging System Using Monopole Antenna with Cylindrical Reflector and Silicon Lens

    Science.gov (United States)

    Mizuno, Maya; Fukunaga, Kaori; Suzuki, Masaki; Saito, Shingo; Fujii, Katsumi; Hosako, Iwao; Yamanaka, Yukio

    2011-04-01

    We built a reflection imaging system that uses a monopole antenna with a cylindrical reflector and silicon semi-spherical lens for millimeter waves to identify detachments of alabaster from support material such as wood and stone, which can be subject to painting deterioration. Based on the electric field property near the monopole antenna in the system and the lens effect, the system was able to clearly image a test sample made of 2-mm width aluminium tape, which was placed within a range of approximately 10 mm from the lens. In practical imaging testing using a detachment model, which consists of alabaster and wood plating, the result also showed the possibility of observing slight detachment of the alabaster from the wood more easily than an imaging with large numerical aperture.

  8. Sputtered Encapsulation as Wafer Level Packaging for Isolatable MEMS Devices: A Technique Demonstrated on a Capacitive Accelerometer

    Directory of Open Access Journals (Sweden)

    Azrul Azlan Hamzah

    2008-11-01

    Full Text Available This paper discusses sputtered silicon encapsulation as a wafer level packaging approach for isolatable MEMS devices. Devices such as accelerometers, RF switches, inductors, and filters that do not require interaction with the surroundings to function, could thus be fully encapsulated at the wafer level after fabrication. A MEMSTech 50g capacitive accelerometer was used to demonstrate a sputtered encapsulation technique. Encapsulation with a very uniform surface profile was achieved using spin-on glass (SOG as a sacrificial layer, SU-8 as base layer, RF sputtered silicon as main structural layer, eutectic gold-silicon as seal layer, and liquid crystal polymer (LCP as outer encapsulant layer. SEM inspection and capacitance test indicated that the movable elements were released after encapsulation. Nanoindentation test confirmed that the encapsulated device is sufficiently robust to withstand a transfer molding process. Thus, an encapsulation technique that is robust, CMOS compatible, and economical has been successfully developed for packaging isolatable MEMS devices at the wafer level.

  9. Update on cellular encapsulation.

    Science.gov (United States)

    Smith, Kate E; Johnson, Robert C; Papas, Klearchos K

    2018-05-06

    There is currently a significant disparity between the number of patients who need lifesaving transplants and the number of donated human organs. Xenotransplantation is a way to address this disparity and attempts to enable the use of xenogeneic tissues have persisted for centuries. While immunologic incompatibilities have presented a persistent impediment to their use, encapsulation may represent a way forward for the use of cell-based xenogeneic therapeutics without the need for immunosuppression. In conjunction with modern innovations such as the use of bioprinting, incorporation of immune modulating molecules into capsule membranes, and genetic engineering, the application of xenogeneic cells to treat disorders ranging from pain to liver failure is becoming increasingly realistic. The present review discusses encapsulation in the context of xenotransplantation, focusing on the current status of clinical trials, persistent issues such as antigen shedding, oxygen availability, and donor selection, and recent developments that may address these limitations. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  10. Encapsulation of ropivacaine in a combined (donor-acceptor, ionic-gradient liposomal system promotes extended anesthesia time.

    Directory of Open Access Journals (Sweden)

    Camila Morais Gonçalves da Silva

    Full Text Available Ropivacaine is a local anesthetic with similar potency but lower systemic toxicity than bupivacaine, the most commonly used spinal anesthetic. The present study concerns the development of a combined drug delivery system for ropivacaine, comprised of two types of liposomes: donor multivesicular vesicles containing 250 mM (NH42SO4 plus the anesthetic, and acceptor large unilamellar vesicles with internal pH of 5.5. Both kinds of liposomes were composed of hydrogenated soy-phosphatidylcholine:cholesterol (2:1 mol% and were prepared at pH 7.4. Dynamic light scattering, transmission electron microscopy and electron paramagnetic resonance techniques were used to characterize the average particle size, polydispersity, zeta potential, morphology and fluidity of the liposomes. In vitro dialysis experiments showed that the combined liposomal system provided significantly longer (72 h release of ropivacaine, compared to conventional liposomes (~45 h, or plain ropivacaine (~4 h (p <0.05. The pre-formulations tested were significantly less toxic to 3T3 cells, with toxicity increasing in the order: combined system < ropivacaine in donor or acceptor liposomes < ropivacaine in conventional liposomes < plain ropivacaine. The combined formulation, containing 2% ropivacaine, increased the anesthesia duration up to 9 h after subcutaneous infiltration in mice. In conclusion, a promising drug delivery system for ropivacaine was described, which can be loaded with large amounts of the anesthetic (2%, with reduced in vitro cytotoxicity and extended anesthesia time.

  11. Experimental investigation of the energy performance of a novel Micro-encapsulated Phase Change Material (MPCM) slurry based PV/T system

    International Nuclear Information System (INIS)

    Qiu, Zhongzhu; Ma, Xiaoli; Zhao, Xudong; Li, Peng; Ali, Samira

    2016-01-01

    Highlights: • An experimental investigation to a novel MPCM slurry based PV/T system was conducted. • The system had the reduced solar efficiency at a higher solar radiation. • The system had the increased solar efficiency at a higher slurry Reynolds number. • The most favourite MPCM concentration was around 10%. • The experimental results approved the accuracy of the established computer model. - Abstract: As a follow-on work of the authors’ theoretical study, the paper presented an experimental investigation into the energy performance of a novel PV/T thermal and power system employing the Micro-encapsulated Phase Change Material (MPCM) slurry as the working fluid. A prototype PV/T module of 800 mm × 1600 mm × 50 mm was designed and constructed based on the previous modelling recommendation. The performance of the PV/T module and associated thermal and power system were tested under various solar radiations, slurry Reynolds numbers and MPCM concentrations. It was found that (1) increasing solar radiation led to the increased PV/T module temperature, decreased solar thermal and electrical efficiencies and reduced slurry pressure drop; (2) increasing the slurry Reynolds number led to the increased solar thermal and electrical efficiencies, decreased module temperature, and increased pressure drop; and (3) increasing the MPCM concentration led to the reduced module temperature and increased pressure drop. The experimental results were used to examine the accuracy of the established computer model, giving a derivation scale ranging from 1.1% to 6.1% which is an acceptable error level for general engineering simulation. The recommended operational conditions of the PV/T system were (1) MPCM slurry weight concentration of 10%, (2) slurry Reynolds number of 3000, and (3) solar radiation of 500–700 W/m"2; at which the system could achieve the net overall solar efficiencies of 80.8–83.9%. To summarise, the MPCM slurry based PV/T thermal and power system

  12. Bifurcation of synchronous oscillations into torus in a system of two reciprocally inhibitory silicon neurons: Experimental observation and modeling

    International Nuclear Information System (INIS)

    Bondarenko, Vladimir E.; Cymbalyuk, Gennady S.; Patel, Girish; DeWeerth, Stephen P.; Calabrese, Ronald L.

    2004-01-01

    Oscillatory activity in the central nervous system is associated with various functions, like motor control, memory formation, binding, and attention. Quasiperiodic oscillations are rarely discussed in the neurophysiological literature yet they may play a role in the nervous system both during normal function and disease. Here we use a physical system and a model to explore scenarios for how quasiperiodic oscillations might arise in neuronal networks. An oscillatory system of two mutually inhibitory neuronal units is a ubiquitous network module found in nervous systems and is called a half-center oscillator. Previously we created a half-center oscillator of two identical oscillatory silicon (analog Very Large Scale Integration) neurons and developed a mathematical model describing its dynamics. In the mathematical model, we have shown that an in-phase limit cycle becomes unstable through a subcritical torus bifurcation. However, the existence of this torus bifurcation in experimental silicon two-neuron system was not rigorously demonstrated or investigated. Here we demonstrate the torus predicted by the model for the silicon implementation of a half-center oscillator using complex time series analysis, including bifurcation diagrams, mapping techniques, correlation functions, amplitude spectra, and correlation dimensions, and we investigate how the properties of the quasiperiodic oscillations depend on the strengths of coupling between the silicon neurons. The potential advantages and disadvantages of quasiperiodic oscillations (torus) for biological neural systems and artificial neural networks are discussed

  13. Melting of Pb clusters encapsulated in large fullerenes

    International Nuclear Information System (INIS)

    Delogu, Francesco

    2011-01-01

    Graphical abstract: Encapsulation significantly increases the melting point of nanometer-sized Pb particles with respect to the corresponding unsupported ones. Highlights: → Nanometer-sized Pb particles are encapsulated in fullerene cages. → Their thermal behavior is studied by molecular dynamics simulations. → Encapsulated particles undergo a pressure rise as temperature increases. → Encapsulated particles melt at temperatures higher than unsupported ones. - Abstract: Molecular dynamics simulations have been employed to explore the melting behavior of nanometer-sized Pb particles encapsulated in spherical and polyhedral fullerene cages of suitable size. The encapsulated particles, as well as the corresponding unsupported ones for comparison, were submitted to a gradual temperature rise. Encapsulation is shown to severely affect the thermodynamic behavior of Pb particles due to the different thermal expansion coefficients of particles and cages. This determines a volume constraint that induces a rise of pressure inside the fullerene cages, which operate for particles as rigid confinement systems. The result is that surface pre-melting and melting processes occur in encapsulated particles at temperatures higher than in unsupported ones.

  14. Radiation Effects of n-type, Low Resistivity, Spiral Silicon Drift Detector Hybrid Systems

    International Nuclear Information System (INIS)

    Chen, W.; De Geronimo, G.; Carini, G.A.; Gaskin, J.A.; Keister, J.W.; Li, S.; Li, Z.; Ramsey, B.D.; Siddons, D.P.; Smith, G.C.; Verbitskaya, E.

    2011-01-01

    We have developed a new thin-window, n-type, low-resistivity, spiral silicon drift detector (SDD) array - to be used as an extraterrestrial X-ray spectrometer (in varying environments) for NASA. To achieve low-energy response, a thin SDD entrance window was produced using a previously developed method. These thin-window devices were also produced on lower resistivity, thinner, n-type, silicon material, effectively ensuring their radiation hardness in anticipation of operation in potentially harsh radiation environments (such as found around the Jupiter system). Using the Indiana University Cyclotron Facility beam line RERS1, we irradiated a set of suitable diodes up to 5 Mrad and the latest iteration of our ASICs up to 12 Mrad. Then we irradiated two hybrid detectors consisting of newly, such-produced in-house (BNL) SDD chips bonded with ASICs with doses of 0.25 Mrad and 1 Mrad. Also we irradiated another hybrid detector consisting of previously produced (by KETEK) on n-type, high-resistivity SDD chip bonded with BNL's ASICs with a dose of 1 Mrad. The measurement results of radiated diodes (up to 5 Mrad), ASICs (up to 12 Mrad) and hybrid detectors (up to 1 Mrad) are presented here.

  15. Transparent silicon strip sensors for the optical alignment of particle detector systems

    International Nuclear Information System (INIS)

    Blum, W.; Kroha, H.; Widmann, P.

    1995-05-01

    Modern large-area precision tracking detectors require increasing accuracy for the alignment of their components. A novel multi-point laser alignment system has been developed for such applications. The position of detector components with respect to reference laser beams is monitored by semi-transparent optical position sensors which work on the principle of silicon strip photodiodes. Two types of custom designed transparent strip sensors, based on crystalline and on amorphous silicon as active material, have been studied. The sensors are optimised for the typical diameters of collimated laser beams of 3-5 mm over distances of 10-20 m. They provide very high position resolution, on the order of 1 μm, uniformly over a wide measurement range of several centimeters. The preparation of the sensor surfaces requires special attention in order to achieve high light transmittance and minimum distortion of the traversing laser beams. At selected wavelengths, produced by laser diodes, transmission rates above 90% have been achieved. This allows to position more than 30 sensors along one laser beam. The sensors will be equipped with custom designed integrated readout electronics. (orig.)

  16. A high rate, low noise, x-ray silicon strip detector system

    International Nuclear Information System (INIS)

    Ludewigt, B.; Jaklevic, J.; Kipnis, I.; Rossington, C.; Spieler, H.

    1993-11-01

    An x-ray detector system, based on a silicon strip detector wire-bonded to a low noise charge-senstive amplifier integrated circuit, has been developed for synchrotron radiation experiments which require very high count rates and good energy resolution. Noise measurements and x-ray spectra were taken using a 6 mm long, 55 μm pitch strip detector in conjunction with a prototype 16-channel charge-sensitive preamplifier, both fabricated using standard 1.2 μm CMOS technology. The detector system currently achieves an energy resolution of 350 eV FWHM at 5.9 key, 2 μs peaking time, when cooled to -5 degree C

  17. Compact tunable silicon photonic differential-equation solver for general linear time-invariant systems.

    Science.gov (United States)

    Wu, Jiayang; Cao, Pan; Hu, Xiaofeng; Jiang, Xinhong; Pan, Ting; Yang, Yuxing; Qiu, Ciyuan; Tremblay, Christine; Su, Yikai

    2014-10-20

    We propose and experimentally demonstrate an all-optical temporal differential-equation solver that can be used to solve ordinary differential equations (ODEs) characterizing general linear time-invariant (LTI) systems. The photonic device implemented by an add-drop microring resonator (MRR) with two tunable interferometric couplers is monolithically integrated on a silicon-on-insulator (SOI) wafer with a compact footprint of ~60 μm × 120 μm. By thermally tuning the phase shifts along the bus arms of the two interferometric couplers, the proposed device is capable of solving first-order ODEs with two variable coefficients. The operation principle is theoretically analyzed, and system testing of solving ODE with tunable coefficients is carried out for 10-Gb/s optical Gaussian-like pulses. The experimental results verify the effectiveness of the fabricated device as a tunable photonic ODE solver.

  18. Silicone-oil-based subvisible particles: their detection, interactions, and regulation in prefilled container closure systems for biopharmaceuticals.

    Science.gov (United States)

    Felsovalyi, Flora; Janvier, Sébastien; Jouffray, Sébastien; Soukiassian, Hervé; Mangiagalli, Paolo

    2012-12-01

    Recent increased regulatory scrutiny concerning subvisible particulates (SbVPs) in parenteral formulations of biologics has led to the publication of numerous articles about the sources, characteristics, implications, and approaches to monitoring and detecting SbVPs. Despite varying opinions on the level of associated risks and method of regulation, nearly all industry scientists and regulators agree on the need for monitoring and reporting visible and subvisible particles. As prefillable drug delivery systems have become a prominent packaging option, silicone oil, a common primary packaging lubricant, may play a role in the appearance of particles. The goal of this article is to complement the current SbVP knowledge base with new insights into the evolution of silicone-oil-related particulates and their interactions with components in prefillable systems. We propose a "toolbox" for improved silicone-oil-related particulate detection and enumeration, and discuss the benefits and limitations of approaches for lowering and controlling silicone oil release in parenterals. Finally, we present surface cross-linking of silicone as the recommended solution for achieving significant SbVP reduction without negatively affecting functional performance. Copyright © 2012 Wiley Periodicals, Inc.

  19. Studies and research concerning BNFP design and construction of a spent-fuel disassembly/encapsulation system

    International Nuclear Information System (INIS)

    Dabolt, R.J.

    1981-04-01

    Commercial light water power reactor operation in the United States is developing a cumbersome inventory of spent fuel. Systems for interim storage and handling of this fuel are being developed by the Federal Government and industry. Disassembly and canning of the spent fuel elements is one of these systems. It has the potential to double the storage capacity of a prereprocessing storage facility or to triple the capacity of conventional shipping casks. Prototype equipment and controls required to perform this operation in a dry environment have been primarily designed and fabricated at the Barnwell Nuclear Fuel Plant (BNFP). Ridihalgh, Eggers, and Associates have provided design support and fabrication of the control system. This system is capable of extracting and canning the fuel pins and compacting the nonfuel-bearing components of spent fuel assemblies at processing rates of 10 to 12 assemblies per day. The process also provides the potential for enhanced inspection and assay of spent fuel by reducing the interference encountered from the high gamma fields of the nonfuel bearing hardware

  20. Research of high speed data readout and pre-processing system based on xTCA for silicon pixel detector

    International Nuclear Information System (INIS)

    Zhao Jingzhou; Lin Haichuan; Guo Fang; Liu Zhen'an; Xu Hao; Gong Wenxuan; Liu Zhao

    2012-01-01

    As the development of the detector, Silicon pixel detectors have been widely used in high energy physics experiments. It needs data processing system with high speed, high bandwidth and high availability to read data from silicon pixel detectors which generate more large data. The same question occurs on Belle II Pixel Detector which is a new style silicon pixel detector used in SuperKEKB accelerator with high luminance. The paper describes the research of High speed data readout and pre-processing system based on xTCA for silicon pixel detector. The system consists of High Performance Computer Node (HPCN) based on xTCA and ATCA frame. The HPCN consists of 4XFPs based on AMC, 1 AMC Carrier ATCA Board (ACAB) and 1 Rear Transmission Module. It characterized by 5 high performance FPGAs, 16 fiber links based on RocketIO, 5 Gbit Ethernet ports and DDR2 with capacity up to 18GB. In a ATCA frame, 14 HPCNs make up a system using the high speed backplane to achieve the function of data pre-processing and trigger. This system will be used on the trigger and data acquisition system of Belle II Pixel detector. (authors)

  1. Micro-Encapsulation of Probiotics

    Science.gov (United States)

    Meiners, Jean-Antoine

    Micro-encapsulation is defined as the technology for packaging with the help of protective membranes particles of finely ground solids, droplets of liquids or gaseous materials in small capsules that release their contents at controlled rates over prolonged periods of time under the influences of specific conditions (Boh, 2007). The material encapsulating the core is referred to as coating or shell.

  2. Development of a silicon tracking and vertex detection system for the CBM experiment at FAIR

    International Nuclear Information System (INIS)

    Heuser, Johann M.

    2007-01-01

    The compressed baryonic matter (CBM) experiment is a fixed-target heavy-ion spectrometer planned at the future international Facility for Antiproton and Ion Research (FAIR) at GSI. The CBM research program will explore the phase diagram of Quantum Chromo Dynamics (QCD) in the region of high baryon chemical potentials, in other words nuclear matter at extreme densities. Matter of such forms is believed to exist in the interior of neutron stars and in the cores of certain types of supernovae. In the laboratory, the dense nuclear medium is created in collisions of heavy-ion beams with nuclear targets. With beam intensities of up to 10 12 ions per pulse, beam energies up to 45 GeV/nucleon, and high availability the SIS-300 synchrotron of FAIR will offer unique opportunities for this research. The CBM detector will identify hadrons and leptons in nuclear collisions with up to 1000 charged particles at event rates up to 10 MHz. The experiment will be optimized in particular for the detection of rare probes, like hadronic decays of D mesons and leptonic decays of light vector mesons, that can yield information on the initial dense phase of the collisions. The challenge is to accomplish in this environment high-resolution charged particle tracking, momentum measurement and secondary vertex selection with a silicon tracking and vertex detection system, the central component of the CBM detector. The system requirements include a very low material budget, radiation tolerant sensors with high spatial resolution, and a fast readout compatible with high-level-only triggers. The paper discusses the concept of the silicon detection system, the optimization of its layout, and the R and D on micro-strip and pixel sensors as well as front-end electronics for the building blocks of the detector stations

  3. Encapsulation of Clay Platelets inside Latex Particles

    NARCIS (Netherlands)

    Voorn, D.J.; Ming, W.; Herk, van A.M.; Fernando, R.H.; Sung, Li-Piin

    2009-01-01

    We present our recent attempts in encapsulating clay platelets inside latex particles by emulsion polymerization. Face modification of clay platelets by cationic exchange has been shown to be insufficient for clay encapsulation, leading to armored latex particles. Successful encapsulation of

  4. Microstrip silicon detectors in a bent crystal based collimation system: The UA9 experiment

    International Nuclear Information System (INIS)

    Bolognini, D.

    2010-01-01

    In a hadron accelerator like Lhc, a collimation system needs to be developed to protect the accelerator itself from the beam loss damage, increasing the beam luminosity. At present, a classical robust multi-stage collimation system (based on amorphous jaws) allows to protect Lhc, but limits the luminosity to the 40% of the nominal value. In order to solve this problem, a series of low-impedance collimation systems is being developed for the second Lhc collimation phase: among these, a key role could be played by bent crystals. In a bent crystal, in fact, charged particles can be deviated in a given direction with a high efficiency, reducing the impedance and increasing the luminosity. After the satisfactory results on extracted beams, it was decided to test bent crystals on a circular accelerator (the Super Proton Synchrotron Sps at CERN): the UA9 experiment was born. In order to qualify the crystal behavior, a tracking system has been developed: the system is based on microstrip silicon detectors readout by self-triggering ASICs with a spatial resolution of the order of 5 μm; the system, completely remotely controlled and based on the optical fiber transmission, would be able to measure the beam halo phase space x - x 1 . This paper, after a brief introduction of the UA9 experiment, will describe the tracking system and the first results obtained in the commissioning phase and data takings with a detector prototype.

  5. Experimental test of a hot water storage system including a macro-encapsulated phase change material (PCM)

    Science.gov (United States)

    Mongibello, L.; Atrigna, M.; Bianco, N.; Di Somma, M.; Graditi, G.; Risi, N.

    2017-01-01

    Thermal energy storage systems (TESs) are of fundamental importance for many energetic systems, essentially because they permit a certain degree of decoupling between the heat or cold production and the use of the heat or cold produced. In the last years, many works have analysed the addition of a PCM inside a hot water storage tank, as it can allow a reduction of the size of the storage tank due to the possibility of storing thermal energy as latent heat, and as a consequence its cost and encumbrance. The present work focuses on experimental tests realized by means of an indoor facility in order to analyse the dynamic behaviour of a hot water storage tank including PCM modules during a charging phase. A commercial bio-based PCM has been used for the purpose, with a melting temperature of 58°C. The experimental results relative to the hot water tank including the PCM modules are presented in terms of temporal evolution of the axial temperature profile, heat transfer and stored energy, and are compared with the ones obtained by using only water as energy storage material. Interesting insights, relative to the estimation of the percentage of melted PCM at the end of the experimental test, are presented and discussed.

  6. Oxygen Measurements in Liposome Encapsulated Hemoglobin

    Science.gov (United States)

    Phiri, Joshua Benjamin

    Liposome encapsulated hemoglobins (LEH's) are of current interest as blood substitutes. An analytical methodology for rapid non-invasive measurements of oxygen in artificial oxygen carriers is examined. High resolution optical absorption spectra are calculated by means of a one dimensional diffusion approximation. The encapsulated hemoglobin is prepared from fresh defibrinated bovine blood. Liposomes are prepared from hydrogenated soy phosphatidylcholine (HSPC), cholesterol and dicetylphosphate using a bath sonication method. An integrating sphere spectrophotometer is employed for diffuse optics measurements. Data is collected using an automated data acquisition system employing lock-in -amplifiers. The concentrations of hemoglobin derivatives are evaluated from the corresponding extinction coefficients using a numerical technique of singular value decomposition, and verification of the results is done using Monte Carlo simulations. In situ measurements are required for the determination of hemoglobin derivatives because most encapsulation methods invariably lead to the formation of methemoglobin, a nonfunctional form of hemoglobin. The methods employed in this work lead to high resolution absorption spectra of oxyhemoglobin and other derivatives in red blood cells and liposome encapsulated hemoglobin (LEH). The analysis using singular value decomposition method offers a quantitative means of calculating the fractions of oxyhemoglobin and other hemoglobin derivatives in LEH samples. The analytical methods developed in this work will become even more useful when production of LEH as a blood substitute is scaled up to large volumes.

  7. Encapsulated scintillation detector

    International Nuclear Information System (INIS)

    Toepke, I.L.

    1982-01-01

    A scintillation detector crystal is encapsulated in a hermetically sealed housing having a glass window. The window may be mounted in a ring by a compression seal formed during cooling of the ring and window after heating. The window may be chemically bonded to the ring with or without a compression seal. The ring is welded to the housing along thin weld flanges to reduce the amount of weld heat which must be applied. A thin section is provided to resist the flow of welding heat to the seal between the ring and the window thereby forming a thermal barrier. The thin section may be provided by a groove cut partially through the wall of the ring. A layer of PTFE between the tubular body and the crystal minimizes friction created by thermal expansion. Spring washers urge the crystal towards the window. (author)

  8. Liposome-encapsulated chemotherapy

    DEFF Research Database (Denmark)

    Børresen, B.; Hansen, A. E.; Kjær, A.

    2018-01-01

    Cytotoxic drugs encapsulated into liposomes were originally designed to increase the anticancer response, while minimizing off-target adverse effects. The first liposomal chemotherapeutic drug was approved for use in humans more than 20years ago, and the first publication regarding its use...... to inherent issues with the enhanced permeability and retention effect, the tumour phenomenon which liposomal drugs exploit. This effect seems very heterogeneously distributed in the tumour. Also, it is potentially not as ubiquitously occurring as once thought, and it may prove important to select patients...... not resolve the other challenges that liposomal chemotherapy faces, and more work still needs to be done to determine which veterinary patients may benefit the most from liposomal chemotherapy....

  9. New process encapsulates

    International Nuclear Information System (INIS)

    Mueller, J.J.

    1982-01-01

    The results of the various aspects of this study indicate that the encapsulation process is not only capable of reducing the percent of Radon-222 emanation but also reduces the possibility of the leaching of toxic elements. Radon-222 emanation after solidification showed a 93.51% reduction from the slurry. The Gamma Spectral Analyses of short-lived Radon daughters supported the above findings. Leach studies on solidified refinery waste and transformer oils indicate there is a significant reduction in the possibility of toxic substances leaching out of the solidified samples. Further studies are needed to confirm the results of this investigation; however, the present findings indicate that the process could substantially reduce Radon-222 exhalation into the environment from uranium tailings ponds and reduce toxic leachates from hazardous waste materials

  10. Porous silicon based micro-opto-electro-mechanical-systems (MOEMS) components for free space optical interconnects

    Science.gov (United States)

    Song, Da

    2008-02-01

    One of the major challenges confronting the current integrated circuits (IC) industry is the metal "interconnect bottleneck". To overcome this obstacle, free space optical interconnects (FSOIs) can be used to address the demand for high speed data transmission, multi-functionality and multi-dimensional integration for the next generation IC. One of the crucial elements in FSOIs system is to develop a high performance and flexible optical network to transform the incoming optical signal into a distributed set of optical signals whose direction, alignment and power can be independently controlled. Among all the optical materials for the realization of FSOI components, porous silicon (PSi) is one of the most promising candidates because of its unique optical properties, flexible fabrication methods and integration with conventional IC material sets. PSi-based Distributed Bragg Reflector (DBR) and Fabry-Perot (F-P) structures with unique optical properties are realized by electrochemical etching of silicon. By incorporating PSi optical structures with Micro-Opto-Electro-Mechanical-Systems (MOEMS), several components required for FSOI have been developed. The first type of component is the out-of-plane freestanding optical switch. Implementing a PSi DBR structure as an optically active region, the device can realize channel selection by changing the tilting angle of the micromirror supported by the thermal bimorph actuator. All the fabricated optical switches have reached kHz working frequency and life time of millions of cycles. The second type of component is the in-plane tunable optical filter. By introducing PSi F-P structure into the in-plane PSi film, a thermally tunable optical filter with a sensitivity of 7.9nm/V has been realized for add/drop optical signal selection. Also, for the first time, a new type of PSi based reconfigurable diffractive optical element (DOE) has been developed. By using patterned photoresist as a protective mask for electrochemical

  11. Status of the silicon strip high-rate FASTBUS readout system

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez, H.; Barsotti, E.; Bowden, M.; Christian, D.; Chramowicz, J.; Fachin, M.; Haldeman, M.; Hoff, J.; Holmes, S.; Rotolo, C.; Romero, A.; Slimmer, D.; Swoboda, C.; Trendler, R.; Urish, J.; Yarema, R.; Zimmerman, T.; Zimmermann, S.; Kowald, W.; MacManus, A.; Recagni, M.; Segal, J.; Spentzouris, P.

    1991-11-01

    Our new readout system was developed in collaboration with, and largely to the specification of, the E771 experimenters. E771 is a fixed target experiment designed to study the production of B hadrons by an 800 GeV/c proton beam. The experiment will operate at rates of up to 200 million beam protons per second and 10 million interactions per second. The experimental apparatus will consist of an open geometry magnetic spectrometer featuring good muon and electron identification (much of which was used in E705), and a compact 16000 channel Silicon Strip Detector. In order to satisfy the experimenter's desire to instrument 16000 SSD elements in a package only 5 cm wide, 5 cm high, and 21 cm deep, and in order to meet the performance specifications, we have made extensive use of Application Specific Integrated Circuits'' (ASIC's).

  12. A Silicon detector system on carbon fiber support at small radius

    International Nuclear Information System (INIS)

    Johnson, Marvin E.

    2004-01-01

    The design of a silicon detector for a p(bar p) collider experiment will be described. The detector uses a carbon fiber support structure with sensors positioned at small radius with respect to the beam. A brief overview of the mechanical design is given. The emphasis is on the electrical characteristics of the detector. General principles involved in grounding systems with carbon fiber structures will be covered. The electrical characteristics of the carbon fiber support structure will be presented. Test results imply that carbon fiber must be regarded as a conductor for the frequency region of interest of 10 to 100 MHz. No distinction is found between carbon fiber and copper. Performance results on noise due to pick-up through the low mass fine pitch cables carrying the analogue signals and floating metal is discussed

  13. Status of the silicon strip high-rate FASTBUS readout system

    International Nuclear Information System (INIS)

    Gonzalez, H.; Barsotti, E.; Bowden, M.; Christian, D.; Chramowicz, J.; Fachin, M.; Haldeman, M.; Hoff, J.; Holmes, S.; Rotolo, C.; Romero, A.; Slimmer, D.; Swoboda, C.; Trendler, R.; Urish, J.; Yarema, R.; Zimmerman, T.; Zimmermann, S.; Kowald, W.; MacManus, A.; Recagni, M.; Segal, J.; Spentzouris, P.

    1991-11-01

    Our new readout system was developed in collaboration with, and largely to the specification of, the E771 experimenters. E771 is a fixed target experiment designed to study the production of B hadrons by an 800 GeV/c proton beam. The experiment will operate at rates of up to 200 million beam protons per second and 10 million interactions per second. The experimental apparatus will consist of an open geometry magnetic spectrometer featuring good muon and electron identification (much of which was used in E705), and a compact 16000 channel Silicon Strip Detector. In order to satisfy the experimenter's desire to instrument 16000 SSD elements in a package only 5 cm wide, 5 cm high, and 21 cm deep, and in order to meet the performance specifications, we have made extensive use of ''Application Specific Integrated Circuits'' (ASIC's)

  14. Test of the CMS microstrip silicon tracker readout and control system

    CERN Document Server

    Zghiche, A

    2001-01-01

    The Microstrip Silicon tracker of the CMS detector is designed to provide robust particle tracking and vertex reconstruction within a strong magnetic field in the high luminosity environment of the LHC. The Tracker readout system employs Front-End Driver cards to digitize and buffer the analogue data arriving via optical links from on detector pipeline chips. The control chain of the front-end electronic is built to operate via optical fibers in order to shield the communications from the outside noise. Components close to the final design have been assembled to be tested in the X5 beam area at CERN where a dedicated 25 ns temporal structure beam has been made available by the SPS. This paper describes the hardware and the software developed for readout and control of data acquired by the front-end electronics operating at 40 MHz, Some preliminary results of the tests performed in the 25 ns beam are also given. (8 refs).

  15. Artificial neural systems using memristive synapses and nano-crystalline silicon thin-film transistors

    Science.gov (United States)

    Cantley, Kurtis D.

    Future computer systems will not rely solely on digital processing of inputs from well-defined data sets. They will also be required to perform various computational tasks using large sets of ill-defined information from the complex environment around them. The most efficient processor of this type of information known today is the human brain. Using a large number of primitive elements (˜1010 neurons in the neocortex) with high parallel connectivity (each neuron has ˜104 synapses), brains have the remarkable ability to recognize and classify patterns, predict outcomes, and learn from and adapt to incredibly diverse sets of problems. A reasonable goal in the push to increase processing power of electronic systems would thus be to implement artificial neural networks in hardware that are compatible with today's digital processors. This work focuses on the feasibility of utilizing non-crystalline silicon devices in neuromorphic electronics. Hydrogenated amorphous silicon (a-Si:H) nanowire transistors with Schottky barrier source/drain junctions, as well as a-Si:H/Ag resistive switches are fabricated and characterized. In the transistors, it is found that the on-current scales linearly with the effective width W eff of the channel nanowire array down to at least 20 nm. The solid-state electrolyte resistive switches (memristors) are shown to exhibit the proper current-voltage hysteresis. SPICE models of similar devices are subsequently developed to investigate their performance in neural circuits. The resulting SPICE simulations demonstrate spiking properties and synaptic learning rules that are incredibly similar to those in biology. Specifically, the neuron circuits can be designed to mimic the firing characteristics of real neurons, and Hebbian learning rules are investigated. Finally, some applications are presented, including associative learning analogous to the classical conditioning experiments originally performed by Pavlov, and frequency and pattern

  16. Mixed Waste Salt Encapsulation Using Polysiloxane - Final Report

    International Nuclear Information System (INIS)

    Miller, C.M.; Loomis, G.G.; Prewett, S.W.

    1997-01-01

    A proof-of-concept experimental study was performed to investigate the use of Orbit Technologies polysiloxane grouting material for encapsulation of U.S. Department of Energy mixed waste salts leading to a final waste form for disposal. Evaporator pond salt residues and other salt-like material contaminated with both radioactive isotopes and hazardous components are ubiquitous in the DOE complex and may exceed 250,000,000 kg of material. Current treatment involves mixing low waste percentages (less than 10% by mass salt) with cement or costly thermal treatment followed by cementation to the ash residue. The proposed technology involves simple mixing of the granular salt material (with relatively high waste loadings-greater than 50%) in a polysiloxane-based system that polymerizes to form a silicon-based polymer material. This study involved a mixing study to determine optimum waste loadings and compressive strengths of the resultant monoliths. Following the mixing study, durability testing was performed on promising waste forms. Leaching studies including the accelerated leach test and the toxicity characteristic leaching procedure were also performed on a high nitrate salt waste form. In addition to this testing, the waste form was examined by scanning electron microscope. Preliminary cost estimates for applying this technology to the DOE complex mixed waste salt problem is also given

  17. First images of a digital autoradiography system based on a Medipix2 hybrid silicon pixel detector.

    Science.gov (United States)

    Mettivier, Giovanni; Montesi, Maria Cristina; Russo, Paolo

    2003-06-21

    We present the first images of beta autoradiography obtained with the high-resolution hybrid pixel detector consisting of the Medipix2 single photon counting read-out chip bump-bonded to a 300 microm thick silicon pixel detector. This room temperature system has 256 x 256 square pixels of 55 microm pitch (total sensitive area of 14 x 14 mm2), with a double threshold discriminator and a 13-bit counter in each pixel. It is read out via a dedicated electronic interface and control software, also developed in the framework of the European Medipix2 Collaboration. Digital beta autoradiograms of 14C microscale standard strips (containing separate bands of increasing specific activity in the range 0.0038-32.9 kBq g(-1)) indicate system linearity down to a total background noise of 1.8 x 10(-3) counts mm(-2) s(-1). The minimum detectable activity is estimated to be 0.012 Bq for 36,000 s exposure and 0.023 Bq for 10,800 s exposure. The measured minimum detection threshold is less than 1600 electrons (equivalent to about 6 keV Si). This real-time system for beta autoradiography offers lower pixel pitch and higher sensitive area than the previous Medipix1-based system. It has a 14C sensitivity better than that of micro channel plate based systems, which, however, shows higher spatial resolution and sensitive area.

  18. Safety evaluation for packaging (onsite) singly encapsulated cesium chloride capsules

    International Nuclear Information System (INIS)

    Smyth, W.W.

    1997-01-01

    Three nonstandard Waste Encapsulation and Storage Facility (WESF) cesium chloride capsules are being shipped from WESF (225B building) to the 324 building. They would normally be shipped in the Beneficial Uses Shipping System (BUSS) cask under its US Department of Energy (DOE) license (DOE 1996), but these capsules are nonstandard: one has a damaged or defective weld in the outer layer of encapsulation, and two have the outer encapsulation removed. The 3 capsules, along with 13 other capsules, will be overpacked in the 324 building to meet the requirements for storage in WESF's pool

  19. OSR encapsulation basis -- 100-KW

    International Nuclear Information System (INIS)

    Meichle, R.H.

    1995-01-01

    The purpose of this report is to provide the basis for a change in the Operations Safety Requirement (OSR) encapsulated fuel storage requirements in the 105 KW fuel storage basin which will permit the handling and storing of encapsulated fuel in canisters which no longer have a water-free space in the top of the canister. The scope of this report is limited to providing the change from the perspective of the safety envelope (bases) of the Safety Analysis Report (SAR) and Operations Safety Requirements (OSR). It does not change the encapsulation process itself

  20. New trends in encapsulation of liposoluble vitamins.

    Science.gov (United States)

    Gonnet, M; Lethuaut, L; Boury, F

    2010-09-15

    Liposoluble vitamins (A, D, E, and K) and carotenoids have many benefits on health. They are provided mainly by foods. At pharmacological doses, they can also be used to treat skin diseases, several types of cancer or decrease oxidative stress. These molecules are sensitive to oxidation, thus encapsulation might constitute an appropriate mean to preserve their properties during storage and enhance their physiological potencies. Formulation processes have been adapted for sensitive molecule, limiting their exposure to high temperature, light or oxygen. Each administration pathway, oral, systemic, topical, transdermal and local, requires different particle sizes and release profile. Encapsulation can lead to greater efficiency allowing smaller administration doses thus diminishing potential hypervitaminosis syndrome appearance and side effects. Carrier formulation can be based on vitamin dissolution in lipid media and its stabilization by surfactant mixture, on its entrapment in a matrix or molecular system. Suitability of each type of carrier will be discussed for each pathway. 2010 Elsevier B.V. All rights reserved.

  1. Theoretical study of the structure, energetics, and dynamics of silicon and carbon systems using tight-binding approaches

    International Nuclear Information System (INIS)

    Xu, Chunhui.

    1991-01-01

    Semiempirical interatomic potentials are developed for silicon and carbon by modeling the total energy of the system using tight-binding approaches. The parameters of the models were obtained by fitting to results from accurate first-principles Local Density Functional calculations. Applications to the computation of phonons as a function of volume for diamond-structured silicon and carbon and the thermal expansions for silicon and diamond yields results which agree well with experiment. The physical origin of the negative thermal expansion observed in silicon is explained. A tight-binding total energy model is generated capable of describing carbon systems with a variety of atomic coordinations and topologies. The model reproduces the total energy versus volume curves of various carbon polytypes as well as phonons and elastic constants of diamond and graphite. The model has also been used in the molecular-dynamics simulation of the properties of carbon clusters. The calculated ground-state geometries of small clusters (C 2 --C 10 ) correlates well with results from accurate quantum chemical calculations, and the structural trend of clusters from C 2 to C 60 are investigated. 67 refs., 19 figs

  2. Final Technical Report - Recovery Act: Organic Coatings as Encapsulants for Low Cost, High Performance PV Modules

    Energy Technology Data Exchange (ETDEWEB)

    Stuart Hellring; Jiping Shao; James Poole

    2011-12-05

    The objective of this project was to evaluate the feasibility of utilizing PPG's commercial organic coatings systems as efficient, modernized encapsulants for low cost, high performance, thin film photovoltaic modules. Our hypothesis was that the combination of an anticorrosive coating with a more traditional barrier topcoat would mitigate many electrochemical processes that are now responsible for the significant portion of photovoltaic (PV) failures, thereby nullifying the extremely high moisture barrier requirements of currently used encapsulation technology. Nine commercially available metal primer coatings and six commercially available top coatings were selected for screening. Twenty-one different primer/top coat combinations were evaluated. The primer coatings were shown to be the major contributor to corrosion inhibition, adhesion, and barrier properties. Two primer coatings and one top coating were downselected for testing on specially-fabricated test modules. The coated test modules passed initial current leakage and insulation testing. Damp Heat testing of control modules showed visible corrosion to the bus bar metal, whereas the coated modules showed none. One of the primer/top coat combinations retained solar power performance after Damp Heat testing despite showing some delamination at the EVA/solar cell interface. Thermal Cycling and Humidity Freeze testing resulted in only one test module retaining its power performance. Failure modes depended on the particular primer/top coating combination used. Overall, this study demonstrated that a relatively thin primer/top coating has the potential to replace the potting film and backsheet in crystalline silicon-based photovoltaic modules. Positive signals were received from commercially available coatings developed for applications having performance requirements different from those required for photovoltaic modules. It is likely that future work to redesign and customize these coatings would result in

  3. Sclerosing Encapsulating Peritonitis; Review

    Directory of Open Access Journals (Sweden)

    Norman O. Machado

    2016-05-01

    Full Text Available Sclerosing encapsulating peritonitis (SEP is a rare chronic inflammatory condition of the peritoneum with an unknown aetiology. Also known as abdominal cocoon, the condition occurs when loops of the bowel are encased within the peritoneal cavity by a membrane, leading to intestinal obstruction. Due to its rarity and nonspecific clinical features, it is often misdiagnosed. The condition presents with recurrent episodes of small bowel obstruction and can be idiopathic or secondary; the latter is associated with predisposing factors such as peritoneal dialysis or abdominal tuberculosis. In the early stages, patients can be managed conservatively; however, surgical intervention is necessary for those with advanced stage intestinal obstruction. A literature review revealed 118 cases of SEP; the mean age of these patients was 39 years and 68.0% were male. The predominant presentation was abdominal pain (72.0%, distension (44.9% or a mass (30.5%. Almost all of the patients underwent surgical excision (99.2% without postoperative complications (88.1%.

  4. Interference between PET and MRI sub-systems in a silicon-photomultiplier-based PET/MRI system

    International Nuclear Information System (INIS)

    Yamamoto, Seiichi; Watabe, Hiroshi; Kanai, Yasukazu; Hatazawa, Jun; Aoki, Masaaki; Sugiyama, Eiji; Watabe, Tadashi; Imaizumi, Masao; Shimosegawa, Eku

    2011-01-01

    The silicon-photomultiplier (Si-PM) is a promising photodetector, especially for integrated PET/MRI systems, due to its small size, high gain, and low sensitivity to static magnetic fields. The major problem using a Si-PM-based PET system within the MRI system is the interference between the PET and MRI units. We measured the interference by combining a Si-PM-based PET system with a permanent-magnet MRI system. When the RF signal-induced pulse height exceeded the lower energy threshold level of the PET system, interference between the Si-PM-based PET system and MRI system was detected. The prompt as well as the delayed coincidence count rates of the Si-PM-based PET system increased significantly. These noise counts produced severe artifacts on the reconstructed images of the Si-PM-based PET system. In terms of the effect of the Si-PM-based PET system on the MRI system, although no susceptibility artifact was observed on the MR images, electronic noise from the PET detector ring was detected by the RF coil and reduced the signal-to-noise ratio (S/N) of the MR images. The S/N degradation of the MR images was reduced when the distance between the RF coil and the Si-PM-based PET system was increased. We conclude that reducing the interference between the PET and MRI systems is essential for achieving the optimum performance of integrated Si-PM PET/MRI systems.

  5. A Silicon Carbide Wireless Temperature Sensing System for High Temperature Applications

    Science.gov (United States)

    Yang, Jie

    2013-01-01

    In this article, an extreme environment-capable temperature sensing system based on state-of-art silicon carbide (SiC) wireless electronics is presented. In conjunction with a Pt-Pb thermocouple, the SiC wireless sensor suite is operable at 450 °C while under centrifugal load greater than 1,000 g. This SiC wireless temperature sensing system is designed to be non-intrusively embedded inside the gas turbine generators, acquiring the temperature information of critical components such as turbine blades, and wirelessly transmitting the information to the receiver located outside the turbine engine. A prototype system was developed and verified up to 450 °C through high temperature lab testing. The combination of the extreme temperature SiC wireless telemetry technology and integrated harsh environment sensors will allow for condition-based in-situ maintenance of power generators and aircraft turbines in field operation, and can be applied in many other industries requiring extreme environment monitoring and maintenance. PMID:23377189

  6. Recent Developments on the Silicon Drift Detector readout scheme for the ALICE Inner Tracking System

    CERN Document Server

    Mazza, G; Bonazzola, G C; Bonvicini, V; Cavagnino, D; Cerello, P G; De Remigis, P; Falchieri, D; Gabrielli, A; Gandolfi, E; Giubellino, P; Hernández, R; Masetti, M; Montaño-Zetina, L M; Nouais, D; Rashevsky, A; Rivetti, A; Tosello, F

    1999-01-01

    Proposal of abstract for LEB99, Snowmass, Colorado, 20-24 September 1999Recent developments of the Silicon Drift Detector (SDD) readout system for the ALICE Experiment are presented. The foreseen readout system is based on 2 main units. The first unit consists of a low noise preamplifier, an analog memory which continuously samples the amplifier output, an A/D converter and a digital memory. When the trigger signal validates the analog data, the ADCs convert the samples into a digital form and store them into the digital memory. The second unit performs the zero suppression/data compression operations. In this paper the status of the design is presented, together with the test results of the A/D converter, the multi-event buffer and the compression unit prototype.Summary:In the Inner Tracker System (ITS) of the ALICE experiment the third and the fourth layer of the detectors are SDDs. These detectors provide the measurement of both the energy deposition and the bi-dimensional position of the track. In terms o...

  7. Label-free silicon photonic biosensor system with integrated detector array

    Science.gov (United States)

    Yan, Rongjin; Mestas, Santano P.; Yuan, Guangwei; Safaisini, Rashid; Dandy, David S.

    2010-01-01

    An integrated, inexpensive, label-free photonic waveguide biosensor system with multi-analyte capability has been implemented on a silicon photonics integrated circuit from a commercial CMOS line and tested with nanofilms. The local evanescent array coupled (LEAC) biosensor is based on a new physical phenomenon that is fundamentally different from the mechanisms of other evanescent field sensors. Increased local refractive index at the waveguide’s upper surface due to the formation of a biological nanofilm causes local modulation of the evanescent field coupled into an array of photodetectors buried under the waveguide. The planar optical waveguide biosensor system exhibits sensitivity of 20%/nm photocurrent modulation in response to adsorbed bovine serum albumin (BSA) layers less than 3 nm thick. In addition to response to BSA, an experiment with patterned photoresist as well as beam propagation method simulations support the evanescent field shift principle. The sensing mechanism enables the integration of all optical and electronic components for a multi-analyte biosensor system on a chip. PMID:19606292

  8. Label-free silicon photonic biosensor system with integrated detector array.

    Science.gov (United States)

    Yan, Rongjin; Mestas, Santano P; Yuan, Guangwei; Safaisini, Rashid; Dandy, David S; Lear, Kevin L

    2009-08-07

    An integrated, inexpensive, label-free photonic waveguide biosensor system with multi-analyte capability has been implemented on a silicon photonics integrated circuit from a commercial CMOS line and tested with nanofilms. The local evanescent array coupled (LEAC) biosensor is based on a new physical phenomenon that is fundamentally different from the mechanisms of other evanescent field sensors. Increased local refractive index at the waveguide's upper surface due to the formation of a biological nanofilm causes local modulation of the evanescent field coupled into an array of photodetectors buried under the waveguide. The planar optical waveguide biosensor system exhibits sensitivity of 20%/nm photocurrent modulation in response to adsorbed bovine serum albumin (BSA) layers less than 3 nm thick. In addition to response to BSA, an experiment with patterned photoresist as well as beam propagation method simulations support the evanescent field shift principle. The sensing mechanism enables the integration of all optical and electronic components for a multi-analyte biosensor system on a chip.

  9. Simulated human eye retina adaptive optics imaging system based on a liquid crystal on silicon device

    International Nuclear Information System (INIS)

    Jiang Baoguang; Cao Zhaoliang; Mu Quanquan; Hu Lifa; Li Chao; Xuan Li

    2008-01-01

    In order to obtain a clear image of the retina of model eye, an adaptive optics system used to correct the wave-front error is introduced in this paper. The spatial light modulator that we use here is a liquid crystal on a silicon device instead of a conversional deformable mirror. A paper with carbon granule is used to simulate the retina of human eye. The pupil size of the model eye is adjustable (3-7 mm). A Shack–Hartman wave-front sensor is used to detect the wave-front aberration. With this construction, a value of peak-to-valley is achieved to be 0.086 λ, where λ is wavelength. The modulation transfer functions before and after corrections are compared. And the resolution of this system after correction (691p/m) is very close to the dirraction limit resolution. The carbon granule on the white paper which has a size of 4.7 μm is seen clearly. The size of the retina cell is between 4 and 10 mu;m. So this system has an ability to image the human eye's retina. (classical areas of phenomenology)

  10. Encapsulation process for diffraction gratings.

    Science.gov (United States)

    Ratzsch, Stephan; Kley, Ernst-Bernhard; Tünnermann, Andreas; Szeghalmi, Adriana

    2015-07-13

    Encapsulation of grating structures facilitates an improvement of the optical functionality and/or adds mechanical stability to the fragile structure. Here, we introduce novel encapsulation process of nanoscale patterns based on atomic layer deposition and micro structuring. The overall size of the encapsulated structured surface area is only restricted by the size of the available microstructuring and coating devices; thus, overcoming inherent limitations of existing bonding processes concerning cleanliness, roughness, and curvature of the components. Finally, the process is demonstrated for a transmission grating. The encapsulated grating has 97.5% transmission efficiency in the -1st diffraction order for TM-polarized light, and is being limited by the experimental grating parameters as confirmed by rigorous coupled wave analysis.

  11. The silicon tracking system of the CBM experiment at FAIR. Development of microstrip sensors and signal transmission lines for a low-mass, low-noise system

    International Nuclear Information System (INIS)

    Singla, Minni

    2014-01-01

    In this thesis, different physical and electrical aspects of silicon microstrip sensors and low-mass multi-line readout cables have been investigated. These silicon microstrip sensors and readout cables will be used in the Silicon Tracking System (STS) of the fixed-target heavy-ion Compressed Baryonic Matter (CBM) experiment which is under development at the upcoming Facility for Antiproton and ion Research (FAIR) in Darmstadt, Germany. The highly segmented low-mass tracking system is a central CBM detector system to resolve the high tracking densities of charged particles originating from beam-target interactions. Considering the low material budget requirement the double-sided silicon microstrip detectors have been used in several planar tracking stations. The readout electronics is planned to be installed at the periphery of the tracking stations along with the cooling system. Low-mass multi-line readout cables shall bridge the distance between the microstrip sensors and the readout electronics. The CBM running operational scenario suggests that some parts of the tracking stations are expected to be exposed to a total integrated particle fluence of the order of 1 x 10 14 n eq /cm 2 . After 1 x 10 14 n eq /cm 2 the damaged modules in the tracking stations will be replaced. Thus radiation hard sensor is an important requirement for the sensors. Moreover, to cope with the high reaction rates, free-streaming (triggerless) readout electronics with online event reconstruction must be used which require high signal-to-noise (SNR) ratio (i.e., high signal efficiency, low noise contributions). Therefore, reduction in noise is a major goal of the sensor and cable development. For better insight into the different aspects of the silicon microstrip sensors and multi-line readout cables, the simulation study has been performed using SYNOPSYS TCAD tools. 3D models of the silicon microstrip sensors and the readout cables were implemented which is motivated by the stereoscopic

  12. [Silicone breast prosthesis and rheumatoid arthritis: a new systemic disease: siliconosis. A case report and a critical review of the literature].

    Science.gov (United States)

    Iannello, S; Belfiore, F

    1998-04-01

    Today the number of women receiving breast implants of silicone gel, for augmentation or reconstruction of the breast, is increasing. Silicon implants may cause local complications (such as capsular contracture, rupture, closed capsulotomy, gel "bleed", nodular foreign body granulomas in the capsular tissue and lymph nodes) or general symptoms. An adverse immune reaction with signs and symptoms of rheumatoid disorders is also possible, although an increased frequency of true autoimmune systemic connective tissue diseases is controversial. The US Food and Drug Administration advised that these silicone implants should be used only in reconstructive surgery and as part of clinical trials. Silicone is not an inert substance and silicone compounds were found in the blood and liver of women with silicone breast implants. The development of disease related to silicone implants would depend on genetic factors, so that only a very few women are potentially at risk. HLA-DR53 may be a marker of predisposed subjects. Breast-feeding by women with silicone implants should not be recommended for possible autoimmune disorders in the children. We report the case of an adult female patient with silicone breast implantation for bilateral mastectomy (performed 12 months before) and a unique syndrome characterized by low-grade fever, chronic fatigue, arthralgias of the hands, dysphagia, dry eye, increased level of rheumatoid factor and decreased value of complement C3 and C4. No increased erythrocyte sedimentation rate occurred, and no ANA, nDNA, ENA and AAT autoantibodies were evidence. A critical review of literature (source: MEDLINE 1980-1997) was performed and our case seems to be the first one reported in Italy. The internist should become familiar with the immunological disorders related to silicone breast implants, often so marked to require the explantation of the prostheses to improve symptomatology. However, perhaps due to the leak and spreading of silicone, the progression

  13. Preparation of collagen peptide functionalized chitosan nanoparticles by ionic gelation method: An effective carrier system for encapsulation and release of doxorubicin for cancer drug delivery

    Energy Technology Data Exchange (ETDEWEB)

    Anandhakumar, S., E-mail: rsanandhakumar@gmail.com [SRM Research Institute, SRM University, Kattankulathur, Chennai 603203 (India); Krishnamoorthy, G.; Ramkumar, K.M. [SRM Research Institute, SRM University, Kattankulathur, Chennai 603203 (India); Raichur, A.M. [Department of Materials Engineering, Indian Institute of Science, Bangalore 560012 (India)

    2017-01-01

    In recent years, nanoparticles (NPs) based on biopolymers or peptides are gaining popularity for the encapsulation and release of drug molecules, especially for cancer therapy, due to their ability for targeted and controlled release. The use of collagen peptide (CP) for the preparation of chitosan (CN) NPs is especially interesting as it results in NPs that are stable under physiological conditions. In this work, mono-dispersed pH responsive CPCN NPs of about 100 nm were prepared via ionic gelation method by simple and mild co-precipitation of CN and CP. Investigation of NPs with Fourier transform infra-red (FTIR) spectroscopy and dynamic light scattering (DLS) measurements reveals that hydrogen bonding and electrostatic interactions are believed to be major driving forces for NP formation and drug encapsulation, respectively. Scanning electron microscopic (SEM) investigations show that hard and fine CPCN NPs transform to soft and bigger gel like particles as a function of collagen concentration. The unique “polymeric gel” structure of NPs showed high encapsulation efficiency towards doxorubicin hydrochloride (DOX) as well as pH controlled release. Anti-proliferative and cell viability analysis revealed that DOX loaded NPs showed excellent anti-proliferative characteristics against HeLa cells with favorable biocompatibility against normal cells. Such NPs have high potential for use as smart drug delivery carriers in advanced cancer therapy. - Highlights: • Preparation of collagen peptide functionalized chitosan nanoparticles • Hydrogen bonding plays a key role in particle formation. • Electrostatic interaction plays a key role in drug encapsulation. • Functionalized chitosan particles are more stable than chitosan NPs.

  14. Beam delivery system with a non-digitized diffractive beam splitter for laser-drilling of silicon

    Science.gov (United States)

    Amako, J.; Fujii, E.

    2016-02-01

    We report a beam-delivery system consisting of a non-digitized diffractive beam splitter and a Fourier transform lens. The system is applied to the deep-drilling of silicon using a nanosecond pulse laser in the manufacture of inkjet printer heads. In this process, a circularly polarized pulse beam is divided into an array of uniform beams, which are then delivered precisely to the process points. To meet these requirements, the splitter was designed to be polarization-independent with an efficiency>95%. The optical elements were assembled so as to allow the fine tuning of the effective overall focal length by adjusting the wavefront curvature of the beam. Using the system, a beam alignment accuracy ofbeam array and the throughput was substantially improved (10,000 points on a silicon wafer drilled in ~1 min). This beam-delivery scheme works for a variety of laser applications that require parallel processing.

  15. Fabrication of silicon strip detectors using a step-and-repeat lithography system

    International Nuclear Information System (INIS)

    Holland, S.

    1991-11-01

    In this work we describe the use of a step-and-repeat lithography system (stepper) for the fabrication of silicon strip detectors. Although the field size of the stepper is only 20 mm in diameter, we have fabricated much larger detectors by printing a repetitive strip detector pattern in a step-and-repeat fashion. The basic unit cell is 7 mm in length. The stepper employs a laser interferometer for stage placement, and the resulting high precision allows one to accurately place the repetitive patterns on the wafer. A small overlap between the patterns ensures a continuous strip. A detector consisting of 512 strips on a 50 μm pitch has been fabricated using this technique. The dimensions of the detector are 6.3 cm by 2.56 cm. Yields of over 99% have been achieved, where yield is defined as the percentage of strips with reverse leakage current below 1 nA. In addition to the inherent advantages of a step-and-repeat system, this technique offers great flexibility in the fabrication of large-area strip detectors since the length and width of the detector can be changed by simply reprogramming the stepper computer. Hence various geometry strip detectors can be fabricated with only one set of masks, as opposed to a separate set of masks for each geometry as would be required with a contact or proximity aligner

  16. A radiographic imaging system based upon a 2-D silicon microstrip sensor

    CERN Document Server

    Papanestis, A; Corrin, E; Raymond, M; Hall, G; Triantis, F A; Manthos, N; Evagelou, I; Van den Stelt, P; Tarrant, T; Speller, R D; Royle, G F

    2000-01-01

    A high resolution, direct-digital detector system based upon a 2-D silicon microstrip sensor has been designed, built and is undergoing evaluation for applications in dentistry and mammography. The sensor parameters and image requirements were selected using Monte Carlo simulations. Sensors selected for evaluation have a strip pitch of 50mum on the p-side and 80mum on the n-side. Front-end electronics and data acquisition are based on the APV6 chip and were adapted from systems used at CERN for high-energy physics experiments. The APV6 chip is not self-triggering so data acquisition is done at a fixed trigger rate. This paper describes the mammographic evaluation of the double sided microstrip sensor. Raw data correction procedures were implemented to remove the effects of dead strips and non-uniform response. Standard test objects (TORMAX) were used to determine limiting spatial resolution and detectability. MTFs were determined using the edge response. The results indicate that the spatial resolution of the...

  17. Dynamic hybrid life cycle assessment of energy and carbon of multicrystalline silicon photovoltaic systems.

    Science.gov (United States)

    Zhai, Pei; Williams, Eric D

    2010-10-15

    This paper advances the life cycle assessment (LCA) of photovoltaic systems by expanding the boundary of the included processes using hybrid LCA and accounting for the technology-driven dynamics of embodied energy and carbon emissions. Hybrid LCA is an extended method that combines bottom-up process-sum and top-down economic input-output (EIO) methods. In 2007, the embodied energy was 4354 MJ/m(2) and the energy payback time (EPBT) was 2.2 years for a multicrystalline silicon PV system under 1700 kWh/m(2)/yr of solar radiation. These results are higher than those of process-sum LCA by approximately 60%, indicating that processes excluded in process-sum LCA, such as transportation, are significant. Even though PV is a low-carbon technology, the difference between hybrid and process-sum results for 10% penetration of PV in the U.S. electrical grid is 0.13% of total current grid emissions. Extending LCA from the process-sum to hybrid analysis makes a significant difference. Dynamics are characterized through a retrospective analysis and future outlook for PV manufacturing from 2001 to 2011. During this decade, the embodied carbon fell substantially, from 60 g CO(2)/kWh in 2001 to 21 g/kWh in 2011, indicating that technological progress is realizing reductions in embodied environmental impacts as well as lower module price.

  18. Optical design of ultrashort throw liquid crystal on silicon projection system

    Science.gov (United States)

    Huang, Jiun-Woei

    2017-05-01

    An ultrashort throw liquid crystal on silicon (LCoS) projector for home cinema, virtual reality, and automobile heads-up display has been designed and fabricated. To achieve the best performance and highest-quality image, this study aimed to design wide-angle projection optics and optimize the illumination for LCoS. Based on the telecentric lens projection system and optimized Koehler illumination, the optical parameters were calculated. The projector's optical system consisted of a conic aspheric mirror and image optics using either symmetric double Gauss or a large-angle eyepiece to achieve a full projection angle larger than 155 deg. By applying Koehler illumination, image resolution was enhanced and the modulation transfer function of the image in high spatial frequency was increased to form a high-quality illuminated image. The partial coherence analysis verified that the design was capable of 2.5 lps/mm within a 2 m×1.5 m projected image. The throw ratio was less than 0.25 in HD format.

  19. Measurement of rare probes with the silicon tracking system of the CBM experiment at FAIR

    International Nuclear Information System (INIS)

    Heuser, Johann; Friese, Volker

    2014-01-01

    The Compressed Baryonic Matter (CBM) experiment at FAIR will explore the phase diagram of strongly interacting matter at highest net baryon densities and moderate temperatures. The CBM physics program will be started with beams delivered by the SIS 100 synchrotron, providing energies from 2 to 14 GeV/nucleon for heavy nuclei, up to 14 GeV/nucleon for light nuclei, and 29 GeV for protons. The highest net baryon densities will be explored with ion beams up to 45 GeV/nucleon energy delivered by SIS 300 in the next stage of FAIR. Collision rates up to 10 7 per second are required to produce very rare probes with unprecedented statistics in this energy range. Their signatures are complex. These conditions call for detector systems designed to meet the extreme requirements in terms of rate capability, momentum and spatial resolution, and a novel DAQ and trigger concept which is not limited by latency but by throughput. In this paper we outline the concepts of CBM's central detector, the Silicon Tracking System, and of the First-Level Event Selector, a dedicated computing farm to reduce on-line the raw data volume by up to three orders of magnitude to a recordable rate. Progress with the development of detector and software algorithms are discussed and examples of performance studies on the reconstruction of rare probes at SIS 100 and SIS 300 energies given

  20. Encapsulation and Nano-Encapsulation of Papain Active Sites to Enhance Radiolityc Stability and Decrease Toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Lugão, A. B.; Varca, G. H.C.; Paiffer, F.; Mathor, M. B.; Lopes, P. S.; Rogero, S.; Rogero, J. R. [Comissão Nacional de Energia Nuclear (CNEN), Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo (Brazil)

    2009-07-01

    Papain is used as an ingredient in various enzymatic debridement preparations. Those paste-like preparations are based on water solution and usually are sterilized by radiation. As a consequence, there is a major decrease in papain activity. Papain containing preparations are used in chronic wounds treatment in order to clean and remove the necrotic tissue. However FDA (2008) is taking an action against such products due to severe adverse events reported in patients which were submitted to papain treatments. Thus, the main goal of this proposal is to develop encapsulated papain containing membranes based on hydrogels and silicone rubber in an attempt to achieve a controllable distribution of size and delivery profile, a toxicity reduction and provide stability towards radiation processing through nanoencapsulation with cyclodextrins, which may also provide protection to the enzyme against radiation induced radiolysis. (author)

  1. Encapsulation and Nano-Encapsulation of Papain Active Sites to Enhance Radiolityc Stability and Decrease Toxicity

    International Nuclear Information System (INIS)

    Lugão, A.B.; Varca, G.H.C.; Paiffer, F.; Mathor, M.B.; Lopes, P.S.; Rogero, S.; Rogero, J.R.

    2009-01-01

    Papain is used as an ingredient in various enzymatic debridement preparations. Those paste-like preparations are based on water solution and usually are sterilized by radiation. As a consequence, there is a major decrease in papain activity. Papain containing preparations are used in chronic wounds treatment in order to clean and remove the necrotic tissue. However FDA (2008) is taking an action against such products due to severe adverse events reported in patients which were submitted to papain treatments. Thus, the main goal of this proposal is to develop encapsulated papain containing membranes based on hydrogels and silicone rubber in an attempt to achieve a controllable distribution of size and delivery profile, a toxicity reduction and provide stability towards radiation processing through nanoencapsulation with cyclodextrins, which may also provide protection to the enzyme against radiation induced radiolysis. (author)

  2. Electrospun Phospholipid Fibers as Micro-Encapsulation and Antioxidant Matrices.

    Science.gov (United States)

    Shekarforoush, Elhamalsadat; Mendes, Ana C; Baj, Vanessa; Beeren, Sophie R; Chronakis, Ioannis S

    2017-10-17

    Electrospun phospholipid (asolectin) microfibers were investigated as antioxidants and encapsulation matrices for curcumin and vanillin. These phospholipid microfibers exhibited antioxidant properties which increased after the encapsulation of both curcumin and vanillin. The total antioxidant capacity (TAC) and the total phenolic content (TPC) of curcumin/phospholipid and vanillin/phospholipid microfibers remained stable over time at different temperatures (refrigerated, ambient) and pressures (vacuum, ambient). ¹H-NMR confirmed the chemical stability of both encapsulated curcumin and vanillin within phospholipid fibers. Release studies in aqueous media revealed that the phenolic bioactives were released mainly due to swelling of the phospholipid fiber matrix over time. The above studies confirm the efficacy of electrospun phospholipid microfibers as encapsulation and antioxidant systems.

  3. Electrospun Phospholipid Fibers as Micro-Encapsulation and Antioxidant Matrices

    Directory of Open Access Journals (Sweden)

    Elhamalsadat Shekarforoush

    2017-10-01

    Full Text Available Electrospun phospholipid (asolectin microfibers were investigated as antioxidants and encapsulation matrices for curcumin and vanillin. These phospholipid microfibers exhibited antioxidant properties which increased after the encapsulation of both curcumin and vanillin. The total antioxidant capacity (TAC and the total phenolic content (TPC of curcumin/phospholipid and vanillin/phospholipid microfibers remained stable over time at different temperatures (refrigerated, ambient and pressures (vacuum, ambient. 1H-NMR confirmed the chemical stability of both encapsulated curcumin and vanillin within phospholipid fibers. Release studies in aqueous media revealed that the phenolic bioactives were released mainly due to swelling of the phospholipid fiber matrix over time. The above studies confirm the efficacy of electrospun phospholipid microfibers as encapsulation and antioxidant systems.

  4. Development of Silicon Sensor Characterization System for Future High Energy Physics Experiments

    OpenAIRE

    Preeti kumari; Kavita Lalwani; Ranjeet Dalal; Geetika Jain; Ashutosh Bhardwaj; Kirti Ranjan

    2015-01-01

    The Compact Muon Solenoid (CMS) is one of the general purpose experiments at the Large Hadron Collider (LHC), CERN and has its Tracker built of all silicon strip and pixel sensors. Si sensors are expected to play extremely important role in the upgrades of the existing Tracker for future high luminosity environment and will also be used in future lepton colliders. However, properties of the silicon sensors have to be carefully understood before they can be put in the extremely high luminos...

  5. Analysis of silicon-based integrated photovoltaic-electrochemical hydrogen generation system under varying temperature and illumination

    Institute of Scientific and Technical Information of China (English)

    Vishwa Bhatt; Brijesh Tripathi; Pankaj Yadav; Manoj Kumar

    2017-01-01

    Last decade witnessed tremendous research and development in the area of photo-electrolytic hydrogen generation using chemically stable nanostructured photo-cathode/anode materials.Due to intimately coupled charge separation and photo-catalytic processes,it is very difficult to optimize individual components of such system leading to a very low demonstrated solar-to-fuel efficiency (SFE) of less than 1%.Recently there has been growing interest in an integrated photovoltaic-electrochemical (PV-EC) system based on GaAs solar cells with the demonstrated SFE of 24.5% under concentrated illumination condition.But a high cost of GaAs based solar cells and recent price drop of poly-crystalline silicon (pc-Si) solar cells motivated researchers to explore silicon based integrated PV-EC system.In this paper a theoretical framework is introduced to model silicon-based integrated PV-EC device.The theoretical framework is used to analyze the coupling and kinetic losses of a silicon solar cell based integrated PV-EC water splitting system under varying temperature and illumination.The kinetic loss occurs in the range of 19.1%-27.9% and coupling loss takes place in the range of 5.45%-6.74% with respect to varying illumination in the range of 20-100 mW/cm2.Similarly,the effect of varying temperature has severe impact on the performance of the system,wherein the coupling loss occurs in the range of 0.84%-21.51% for the temperature variation from 25 to 50 ℃.

  6. Characterization of silicon microstrip sensors with a pulsed infrared laser system for the CBM experiment at FAIR

    Energy Technology Data Exchange (ETDEWEB)

    Ghosh, Pradeep [Goethe Univ., Frankfurt (Germany); GSI (Germany); Eschke, Juergen [GSI (Germany); FAIR (Germany); Collaboration: CBM-Collaboration

    2014-07-01

    The Silicon Tracking System (STS) for the Compressed Baryonic Matter (CBM) experiment at FAIR will comprise more than 1200 double-sided silicon microstrip sensors. For the quality assurance of the prototype sensors a laser test system has been built up. The aim of the sensor scans with the pulsed infrared laser system is to determine the charge sharing between strips and to measure the uniformity of the sensor response over the whole active area. The laser system measures the sensor response in an automatized procedure at several thousand positions across the sensor with focused infrared laser light (σ∼15 μm, λ=1060 nm). The duration (5 ns) and power (few mW) of the laser pulses are selected such, that the absorption of the laser light in the 300 μm thick silicon sensors produces a number of about 24k electrons, which is similar to the charge created by minimum ionizing particles in these sensors. Results from the characterization of monolithic active pixel sensors, to understand the spot-size of the laser, and laser scans for different sensors are presented.

  7. Alkaline earth metal, silicon, chlorine, hydrogen. A reaction system for the heterogeneous hydrodehalogenation of silicon tetrachloride to nanocrystalline silicon; Erdalkalimetall-Silicium-Chlor-Wasserstoff. Das Reaktionssystem fuer die heterogene Hydrodehalogenierung von Siliciumtetrachlorid bis zum nanokristallinen Silicium

    Energy Technology Data Exchange (ETDEWEB)

    Fiedler, Katja

    2012-02-17

    Reactions of an alkaline earth metal with a SiCl{sub 4}-H{sub 2} result in a quaternary system with a metastable quaternary phase which separates into the metal chloride and nanocrystalline silicon upon cooling. The present study was dedicated to a making a detailed characterisation of the quaternary phase. For this purpose the properties of the quaternary system were derived from those of the six binary and four ternary systems. The first ever characterisation of the surface by means of photoelectron spectroscopy was undertaken. It also proved possible for the first time to follow the formation reaction by measuring the potential difference across the reaction system. Using the results of the characterisation the author presents first steps towards identifying the formation mechanism involved. [German] Im quaternaeren System Erdalkalimetall-Silicium-Chlor-Wasserstoff bildet sich bei der Umsetzung des Metalls mit einer SiCl{sub 4}-H{sub 2}-Atmosphaere eine quaternaere Phase. Diese metastabile Phase zerfaellt beim Abkuehlen in das Metallchlorid und Silicium in nanokristalliner Form. Die vorliegende Arbeit hat sich mit der tiefergehenden Charakterisierung der quaternaeren Phase beschaeftigt. Dazu wurden die Eigenschaften des quaternaeren Systems aus den Eigenschaften der sechs binaeren und vier ternaeren Systemen abgeleitet. Die Oberflaeche wurde erstmals mit Photoelektronenspektroskopie charakterisiert. Zusaetzlich gelang erstmalig die Verfolgung der Bildungsreaktion durch Messung des Spannungsabfalls ueber das Reaktionssystem. Erste Ansaetze zur Aufklaerung des Bildungsmechanismus ausgehend von den Ergebnissen der Charakterisierung wurden zusaetzlich aufgezeigt.

  8. Study of 236U/238U ratio at CIRCE using a 16-strip silicon detector with a TOF system

    Science.gov (United States)

    De Cesare, M.; De Cesare, N.; D'Onofrio, A.; Gialanella, L.; Terrasi, F.

    2015-04-01

    Accelerator Mass Spectrometry (AMS) is presently the most sensitive technique for the measurement of long-lived actinides, e.g. 236U and xPu isotopes. A new actinide AMS system, based on a 3-MV pelletron tandem accelerator, is operated at the Center for Isotopic Research on Cultural and Environmental Heritage (CIRCE) in Caserta, Italy. In this paper we report on the procedure adopted to increase the 236U abundance sensitivity as low as possible. The energy and position determinations of the 236U ions, using a 16-strip silicon detector have been obtained. A 236U/238U isotopic ratio background level of about 2.9×10-11 was obtained, summing over all the strips, using a Time of Flight-Energy (TOF-E) system with a 16-strip silicon detector (4.9×10-12 just with one strip).

  9. Study of 236U/238U ratio at CIRCE using a 16-strip silicon detector with a TOF system

    Directory of Open Access Journals (Sweden)

    De Cesare M.

    2015-01-01

    Full Text Available Accelerator Mass Spectrometry (AMS is presently the most sensitive technique for the measurement of long-lived actinides, e.g. 236U and xPu isotopes. A new actinide AMS system, based on a 3-MV pelletron tandem accelerator, is operated at the Center for Isotopic Research on Cultural and Environmental Heritage (CIRCE in Caserta, Italy. In this paper we report on the procedure adopted to increase the 236U abundance sensitivity as low as possible. The energy and position determinations of the 236U ions, using a 16-strip silicon detector have been obtained. A 236U/238U isotopic ratio background level of about 2.9×10−11 was obtained, summing over all the strips, using a Time of Flight-Energy (TOF-E system with a 16-strip silicon detector (4.9×10−12 just with one strip.

  10. Influence of additional heat exchanger block on directional solidification system for growing multi-crystalline silicon ingot - A simulation investigation

    Science.gov (United States)

    Nagarajan, S. G.; Srinivasan, M.; Aravinth, K.; Ramasamy, P.

    2018-04-01

    Transient simulation has been carried out for analyzing the heat transfer properties of Directional Solidification (DS) furnace. The simulation results revealed that the additional heat exchanger block under the bottom insulation on the DS furnace has enhanced the control of solidification of the silicon melt. Controlled Heat extraction rate during the solidification of silicon melt is requisite for growing good quality ingots which has been achieved by the additional heat exchanger block. As an additional heat exchanger block, the water circulating plate has been placed under the bottom insulation. The heat flux analysis of DS system and the temperature distribution studies of grown ingot confirm that the established additional heat exchanger block on the DS system gives additional benefit to the mc-Si ingot.

  11. Tunable sustained intravitreal drug delivery system for daunorubicin using oxidized porous silicon.

    Science.gov (United States)

    Hou, Huiyuan; Nieto, Alejandra; Ma, Feiyan; Freeman, William R; Sailor, Michael J; Cheng, Lingyun

    2014-03-28

    Daunorubicin (DNR) is an effective inhibitor of an array of proteins involved in neovascularization, including VEGF and PDGF. These growth factors are directly related to retina scar formation in many devastating retinal diseases. Due to the short vitreous half-life and narrow therapeutic window, ocular application of DNR is limited. It has been shown that a porous silicon (pSi) based delivery system can extend DNR vitreous residence from a few days to 3months. In this study we investigated the feasibility of altering the pore size of the silicon particles to regulate the payload release. Modulation of the etching parameters allowed control of the nano-pore size from 15nm to 95nm. In vitro studies showed that degradation of pSiO2 increased with increasing pore size and the degradation of pSiO2 was approximately constant for a given particle type. The degradation of pSiO2 with 43nm pores was significantly greater than the other two particles with smaller pores, judged by observed and normalized mean Si concentration of the dissolution samples (44.2±8.9 vs 25.7±5.6 or 21.2±4.2μg/mL, pporous silicon dioxide with covalent loading of daunorubicin) with large pores (43nm) yielded a significantly higher DNR level than particles with 15 or 26nm pores (13.5±6.9ng/mL vs. 2.3±1.6ng/mL and 1.1±0.9ng/mL, p<0.0001). After two months of in vitro dynamic release, 54% of the pSiO2-CO2H:DNR particles still remained in the dissolution chamber by weight. In vivo drug release study demonstrated that free DNR in the vitreous at post-injection day 14 was 66.52ng/mL for 95nm pore size pSiO2-CO2H:DNR, 10.76ng/mL for 43nm pSiO2-CO2H:DNR, and only 1.05ng/mL for 15nm pSiO2-CO2H:DNR. Pore expansion from 15nm to 95nm led to a 63 fold increase of DNR release (p<0.0001) and a direct correlation between the pore size and the drug levels in the living eye vitreous was confirmed. The present study demonstrates the feasibility of regulating DNR release from pSiO2 covalently loaded with DNR by

  12. Large-Scale PV Module Manufacturing Using Ultra-Thin Polycrystalline Silicon Solar Cells: Final Subcontract Report, 1 April 2002--28 February 2006

    Energy Technology Data Exchange (ETDEWEB)

    Wohlgemuth, J.; Narayanan, M.

    2006-07-01

    The major objectives of this program were to continue advances of BP Solar polycrystalline silicon manufacturing technology. The Program included work in the following areas. (1) Efforts in the casting area to increase ingot size, improve ingot material quality, and improve handling of silicon feedstock as it is loaded into the casting stations. (2) Developing wire saws to slice 100-..mu..m-thick silicon wafers on 290-..mu..m-centers. (3) Developing equipment for demounting and subsequent handling of very thin silicon wafers. (4) Developing cell processes using 100-..mu..m-thick silicon wafers that produce encapsulated cells with efficiencies of at least 15.4% at an overall yield exceeding 95%. (5) Expanding existing in-line manufacturing data reporting systems to provide active process control. (6) Establishing a 50-MW (annual nominal capacity) green-field Mega-plant factory model template based on this new thin polycrystalline silicon technology. (7) Facilitating an increase in the silicon feedstock industry's production capacity for lower-cost solar-grade silicon feedstock..

  13. Large-Scale PV Module Manufacturing Using Ultra-Thin Polycrystalline Silicon Solar Cells: Annual Subcontract Report, 1 October 2003--30 September 2004

    Energy Technology Data Exchange (ETDEWEB)

    Wohlgemuth, J.; Narayanan, M.

    2005-03-01

    The major objectives of this program are to continue the advancement of BP Solar polycrystalline silicon manufacturing technology. The program includes work in the following areas: Efforts in the casting area to increase ingot size, improve ingot material quality, and improve handling of silicon feedstock as it is loaded into the casting stations; developing wire saws to slice 100- m-thick silicon wafers on 290- m centers; developing equipment for demounting and subsequent handling of very thin silicon wafers; developing cell processes using 100- m-thick silicon wafers that produce encapsulated cells with efficiencies of at least 15.4% at an overall yield exceeding 95%; expanding existing in-line manufacturing data reporting systems to provide active process control; establishing a 50-MW (annual nominal capacity) green-field Mega-plant factory model template based on this new thin polycrystalline silicon technology; facilitating an increase in the silicon feedstock industry's production capacity for lower-cost solar-grade silicon feedstock.

  14. A Smart High Accuracy Silicon Piezoresistive Pressure Sensor Temperature Compensation System

    Directory of Open Access Journals (Sweden)

    Guanwu Zhou

    2014-07-01

    Full Text Available Theoretical analysis in this paper indicates that the accuracy of a silicon piezoresistive pressure sensor is mainly affected by thermal drift, and varies nonlinearly with the temperature. Here, a smart temperature compensation system to reduce its effect on accuracy is proposed. Firstly, an effective conditioning circuit for signal processing and data acquisition is designed. The hardware to implement the system is fabricated. Then, a program is developed on LabVIEW which incorporates an extreme learning machine (ELM as the calibration algorithm for the pressure drift. The implementation of the algorithm was ported to a micro-control unit (MCU after calibration in the computer. Practical pressure measurement experiments are carried out to verify the system’s performance. The temperature compensation is solved in the interval from −40 to 85 °C. The compensated sensor is aimed at providing pressure measurement in oil-gas pipelines. Compared with other algorithms, ELM acquires higher accuracy and is more suitable for batch compensation because of its higher generalization and faster learning speed. The accuracy, linearity, zero temperature coefficient and sensitivity temperature coefficient of the tested sensor are 2.57% FS, 2.49% FS, 8.1 × 10−5/°C and 29.5 × 10−5/°C before compensation, and are improved to 0.13%FS, 0.15%FS, 1.17 × 10−5/°C and 2.1 × 10−5/°C respectively, after compensation. The experimental results demonstrate that the proposed system is valid for the temperature compensation and high accuracy requirement of the sensor.

  15. Silicon detectors

    International Nuclear Information System (INIS)

    Klanner, R.

    1984-08-01

    The status and recent progress of silicon detectors for high energy physics is reviewed. Emphasis is put on detectors with high spatial resolution and the use of silicon detectors in calorimeters. (orig.)

  16. Low-cost encapsulation materials for terrestrial solar cell modules

    Science.gov (United States)

    Cuddihy, E. F.; Baum, B.; Willis, P.

    1979-01-01

    The paper presents the findings of material surveys intended to identify low cost materials which could be functional as encapsulants (by 1986) for terrestrial solar cell modules. Economic analyses have indicated that in order to meet the low cost goal of $2.70 per sq m, some or all of the following material technologies must be developed or advanced: (1) UV screening outer covers; (2) elastomeric acrylics; (3) weatherproofing and waterproofing of structural wood and paper products; (4) transparent UV stabilizers for the UV-sensitive transparent pottants; and (5) cost-effective utilization of silicone and fluorocarbon materials.

  17. An investigation into the use of large area silicon semiconductors in microwave systems

    International Nuclear Information System (INIS)

    Holliday, H.R.

    1999-09-01

    Semiconductor microwave devices are usually manufactured using micron or sub-micron geometries. The equipment needed for these techniques has a high capital cost and demands high overheads. The material traditionally processed for microwave applications is gallium arsenide but during the period of this investigation a move towards the use of silicon and silicon germanium has emerged. This study, which is essentially practical, covers a range of new ideas for components using large area silicon devices. In the course of the study considerable progress has also been made in the understanding of the behaviour of silicon at microwave frequencies, and some of the initial Concepts were shown to be invalid. An accurate determination of the dielectric constant of silicon has been made using quasi optical techniques at microwave frequencies. The fabrication techniques described originate from methods used at Q-par Angus to manufacture large area silicon nuclear radiation detectors. Developed at the University of Birmingham, these are 'wet chemistry' methods that preclude the need for diffusion or other conventional semiconductor processing techniques. Novel microwave components have been developed using these techniques. These include an optically controlled attenuator with multioctave bandwidth and good dynamic range; window devices to reduce the radar cross section of microwave antennas; and microwave cavity devices including a variable-Q cavity. Concepts for millimeter wave filters are discussed, as are areas for further research. During the attenuator study Wheeler's equations have been extended to cover truncated microstrip. It was observed at an early stage in the work that optical excitation was very effective as a method of controlling the devices. This fits well with current trends in electro-optical devices. The piezo resistance effect in silicon has been briefly investigated and a mechanical attenuator exploiting this effect has been developed. (author)

  18. A chemically stable PVD multilayer encapsulation for lithium microbatteries

    International Nuclear Information System (INIS)

    Ribeiro, J F; Sousa, R; Cunha, D J; Vieira, E M F; Goncalves, L M; Silva, M M; Dupont, L

    2015-01-01

    A multilayer physical vapour deposition (PVD) thin-film encapsulation method for lithium microbatteries is presented. Lithium microbatteries with a lithium cobalt oxide (LiCoO 2 ) cathode, a lithium phosphorous oxynitride (LiPON) electrolyte and a metallic lithium anode are under development, using PVD deposition techniques. Metallic lithium film is still the most common anode on this battery technology; however, it presents a huge challenge in terms of material encapsulation (lithium reacts with almost any materials deposited on top and almost instantly begins oxidizing in contact with atmosphere). To prove the encapsulation concept and perform all the experiments, lithium films were deposited by thermal evaporation technique on top of a glass substrate, with previously patterned Al/Ti contacts. Three distinct materials, in a multilayer combination, were tested to prevent lithium from reacting with protection materials and atmosphere. These multilayer films were deposited by RF sputtering and were composed of lithium phosphorous oxide (LiPO), LiPON and silicon nitride (Si 3 N 4 ). To complete the long-term encapsulation after breaking the vacuum, an epoxy was applied on top of the PVD multilayer. In order to evaluate oxidation state of lithium films, the lithium resistance was measured in a four probe setup (cancelling wires/contact resistances) and resistivity calculated, considering physical dimensions. A lithium resistivity of 0.16 Ω μm was maintained for more than a week. This PVD multilayer exonerates the use of chemical vapour deposition (CVD), glove-box chambers and sample manipulation between them, significantly reducing the fabrication cost, since battery and its encapsulation are fabricated in the same PVD chamber. (paper)

  19. A chemically stable PVD multilayer encapsulation for lithium microbatteries

    Science.gov (United States)

    Ribeiro, J. F.; Sousa, R.; Cunha, D. J.; Vieira, E. M. F.; Silva, M. M.; Dupont, L.; Goncalves, L. M.

    2015-10-01

    A multilayer physical vapour deposition (PVD) thin-film encapsulation method for lithium microbatteries is presented. Lithium microbatteries with a lithium cobalt oxide (LiCoO2) cathode, a lithium phosphorous oxynitride (LiPON) electrolyte and a metallic lithium anode are under development, using PVD deposition techniques. Metallic lithium film is still the most common anode on this battery technology; however, it presents a huge challenge in terms of material encapsulation (lithium reacts with almost any materials deposited on top and almost instantly begins oxidizing in contact with atmosphere). To prove the encapsulation concept and perform all the experiments, lithium films were deposited by thermal evaporation technique on top of a glass substrate, with previously patterned Al/Ti contacts. Three distinct materials, in a multilayer combination, were tested to prevent lithium from reacting with protection materials and atmosphere. These multilayer films were deposited by RF sputtering and were composed of lithium phosphorous oxide (LiPO), LiPON and silicon nitride (Si3N4). To complete the long-term encapsulation after breaking the vacuum, an epoxy was applied on top of the PVD multilayer. In order to evaluate oxidation state of lithium films, the lithium resistance was measured in a four probe setup (cancelling wires/contact resistances) and resistivity calculated, considering physical dimensions. A lithium resistivity of 0.16 Ω μm was maintained for more than a week. This PVD multilayer exonerates the use of chemical vapour deposition (CVD), glove-box chambers and sample manipulation between them, significantly reducing the fabrication cost, since battery and its encapsulation are fabricated in the same PVD chamber.

  20. Prototype of a silicon nitride ceramic-based miniplate osteofixation system for the midface.

    Science.gov (United States)

    Neumann, Andreas; Unkel, Claus; Werry, Christoph; Herborn, Christoh U; Maier, Horst R; Ragoss, Christian; Jahnke, Klaus

    2006-06-01

    The favorable properties of silicon nitride (Si3N4) ceramics, such as high mean strength level and fracture toughness, suggest biomedical use as an implant material. Minor reservations about the biocompatibility of Si3N4 ceramics were cleared up by previous in vitro and in vivo investigations. A Si3N4 prototype minifixation system was manufactured and implanted for osteosynthesis of artificial frontal bone defects in 3 minipigs. After 3 months, histological sections, computed tomography (CT) scans, and magnetic resonance imaging (MRI) scans were obtained. Finite element modeling (FEM) was used to simulate stresses and strains on Si3N4 miniplates and screws to calculate survival probabilities. Si3N4 miniplates and screws showed satisfying intraoperative workability. There was no implant loss, displacement, or fracture. Bone healing was complete in all animals. The formation of new bone was observed in direct contact to the implants. The implants showed no artifacts on CT and MRI scanning. FEM simulation confirmed the mechanical reliability of the screws, whereas simulated plate geometries regarding pullout forces at maximum load showed limited safety in a bending situation. Si3N4 ceramics show a good biocompatibility outcome both in vitro and in vivo. In ENT surgery, this ceramic may serve as a biomaterial for osteosynthesis (eg, of the midface including reconstruction the floor of the orbit and the skull base). To our knowledge, this is the first introduction of a ceramic-based miniplate-osteofixation system. Advantages compared with titanium are no risk of implantation to bone with mucosal attachment, no need for explantation, and no interference with radiologic imaging. Disadvantages include the impossibility of individual bending of the miniplates.

  1. Finite element simulations of low-mass readout cables for the CBM Silicon Tracking System using RAPHAEL

    Energy Technology Data Exchange (ETDEWEB)

    Singla, M., E-mail: M.Singla@gsi.de [Goethe University, Frankfurt (Germany); GSI Helmholtzzentrum für Schwerionenforschung GmbH, Darmstadt (Germany); Chatterji, S.; Müller, W.F.J.; Kleipa, V.; Heuser, J.M. [GSI Helmholtzzentrum für Schwerionenforschung GmbH, Darmstadt (Germany)

    2014-01-21

    The first three-dimensional simulation study of thin multi-line readout cables using finite element simulation tool RAPHAEL is being reported. The application is the Silicon Tracking System (STS) of the fixed-target heavy-ion experiment Compressed Baryonic Matter (CBM), under design at the forthcoming accelerator center FAIR in Germany. RAPHAEL has been used to design low-mass analog readout cables with minimum possible Equivalent Noise Charge (ENC). Various trace geometries and trace materials have been explored in detail for this optimization study. These cables will bridge the distance between the microstrip detectors and the signal processing electronics placed at the periphery of the silicon tracking stations. SPICE modeling has been implemented in Sentaurus Device to study the transmission loss (dB loss) in cables and simulation has been validated with measurements. An optimized design having minimum possible ENC, material budget and transmission loss for the readout cables has been proposed.

  2. Development of a Silicon Based Electron Beam Transmission Window for Use in a KrF Excimer Laser System

    CERN Document Server

    Gentile, C A; Hartfield, J W; Hawryluk, R J; Hegeler, F; Heitzenroeder, P J; Jun, C H; Ku, L P; Lamarche, P H; Myers, M C; Parker, J J; Parsells, R F; Payen, M; Raftopoulos, S; Sethian, J D

    2002-01-01

    The Princeton Plasma Physics Laboratory (PPPL), in collaboration with the Naval Research Laboratory (NRL), is currently investigating various novel materials (single crystal silicon, , and ) for use as electron-beam transmission windows in a KrF excimer laser system. The primary function of the window is to isolate the active medium (excimer gas) from the excitation mechanism (field-emission diodes). Chosen window geometry must accommodate electron energy transfer greater than 80% (750 keV), while maintaining structural integrity during mechanical load (1.3 to 2.0 atm base pressure differential, approximate 0.5 atm cyclic pressure amplitude, 5 Hz repetition rate) and thermal load across the entire hibachi area (approximate 0.9 W centre dot cm superscript ''-2''). In addition, the window must be chemically resistant to attack by fluorine free-radicals (hydrofluoric acid, secondary). In accordance with these structural, functional, and operational parameters, a 22.4 mm square silicon prototype window, coated w...

  3. The microscopic mechanism of silicon precipitation in Al/Si system

    International Nuclear Information System (INIS)

    Zenou, V.Y.; Kiv, A.; Fuks, D.; Ezerski, V.; Moiseenko, N.

    2006-01-01

    A Homo-Heterogeneous Mechanism (HHM) for the precipitation of silicon atoms in aluminum is proposed. The main point of HHM is that the formation of critical nucleus consists of two steps. At the first step the pre-critical nucleus is formed. It plays a role of a preferable site for the further hetero-nucleation and then for the growth of Si precipitates on these nuclei. The reported results are based on ab initio calculations of total energy for equilibrium configurations of silicon clusters embedded into aluminum lattice. HHM explains the results of experimental studies of silicon precipitation in quenched Si-Al alloy obtained in this work and by other authors

  4. An all-silicone zoom lens in an optical imaging system

    International Nuclear Information System (INIS)

    Zhao Cun-Hua

    2013-01-01

    An all-silicone zoom lens is fabricated. A tunable metal ringer is fettered around the side edge of the lens. A nylon rope linking a motor is tied, encircling the notch in the metal ringer. While the motor is operating, the rope can shrink or release to change the focal length of the lens. A calculation method is developed to obtain the focal length and the zoom ratio. The testing is carried out in succession. The testing values are compared with the calculated ones, and they tally with each other well. Finally, the imaging performance of the all-silicone lens is demonstrated. The all-silicone lens has potential uses in cellphone cameras, notebook cameras, micro monitor lenses, etc. (electromagnetism, optics, acoustics, heat transfer, classical mechanics, and fluid dynamics)

  5. An all-silicone zoom lens in an optical imaging system

    Science.gov (United States)

    Zhao, Cun-Hua

    2013-09-01

    An all-silicone zoom lens is fabricated. A tunable metal ringer is fettered around the side edge of the lens. A nylon rope linking a motor is tied, encircling the notch in the metal ringer. While the motor is operating, the rope can shrink or release to change the focal length of the lens. A calculation method is developed to obtain the focal length and the zoom ratio. The testing is carried out in succession. The testing values are compared with the calculated ones, and they tally with each other well. Finally, the imaging performance of the all-silicone lens is demonstrated. The all-silicone lens has potential uses in cellphone cameras, notebook cameras, micro monitor lenses, etc.

  6. Development of prototype components for the silicon tracking system of the CBM experiment at FAIR

    Energy Technology Data Exchange (ETDEWEB)

    Lymanets, Anton

    2013-06-26

    The CBM experiment at future accelerator facility FAIR will investigate the properties of nuclear matter under extreme conditions. The experimental programm is different from the heavy-ion experiments at RHIC (BNL) and LHC (CERN) that create nuclear matter at high temperatures. In contrast, the study of the QCD phase diagram in the region of the highest net baryon densities and moderate temperatures that is weakly explored will be performed with high precision. For this, collisions of different heavy-ion beams at the energies of 10-45 GeV/nucleon with nuclear target will be measured. The physics programme of the CBM experiment includes measurement of both rare probes and bulk observables that originate from various phases of a nucleus-nucleus collision. In particular, decay of particles with charm quarks can be registered by reconstructing the decay vertex detached from the primary interaction point by several hundreds of micrometers (e.g., decay length cτ=123 μm for D{sup 0} meson). For this, precise tracking and full event reconstruction with up to 600 charged particle tracks per event within acceptance are required. Other rare probes require operation at interaction rate of up to 10 MHz. The detector system that performs tracking has to provide high position resolution on the order of 10 μm, operate at high rates and have radiation tolerant design with low material budget. The Silicon Tracking System (STS) is being designed for charged-particle tracking in a magnetic field. The system consists of eight tracking station located in the aperture of a dipole magnet with 1 T field. For tracks with momentum above 1 GeV, momentum resolution of such a system is expected to be about 1%. In order to fulfill this task, thorough optimization of the detector design is required. In particular, minimal material budget has to be achieved. Production of a detector module requires research and development activities with respect to the module components and their integration

  7. Toward three-dimensional microelectronic systems: directed self-assembly of silicon microcubes via DNA surface functionalization.

    Science.gov (United States)

    Lämmerhardt, Nico; Merzsch, Stephan; Ledig, Johannes; Bora, Achyut; Waag, Andreas; Tornow, Marc; Mischnick, Petra

    2013-07-02

    The huge and intelligent processing power of three-dimensional (3D) biological "processors" like the human brain with clock speeds of only 0.1 kHz is an extremely fascinating property, which is based on a massively parallel interconnect strategy. Artificial silicon microprocessors are 7 orders of magnitude faster. Nevertheless, they do not show any indication of intelligent processing power, mostly due to their very limited interconnectivity. Massively parallel interconnectivity can only be realized in three dimensions. Three-dimensional artificial processors would therefore be at the root of fabricating artificially intelligent systems. A first step in this direction would be the self-assembly of silicon based building blocks into 3D structures. We report on the self-assembly of such building blocks by molecular recognition, and on the electrical characterization of the formed assemblies. First, planar silicon substrates were functionalized with self-assembling monolayers of 3-aminopropyltrimethoxysilane for coupling of oligonucleotides (single stranded DNA) with glutaric aldehyde. The oligonucleotide immobilization was confirmed and quantified by hybridization with fluorescence-labeled complementary oligonucleotides. After the individual processing steps, the samples were analyzed by contact angle measurements, ellipsometry, atomic force microscopy, and fluorescence microscopy. Patterned DNA-functionalized layers were fabricated by microcontact printing (μCP) and photolithography. Silicon microcubes of 3 μm edge length as model objects for first 3D self-assembly experiments were fabricated out of silicon-on-insulator (SOI) wafers by a combination of reactive ion etching (RIE) and selective wet etching. The microcubes were then surface-functionalized using the same protocol as on planar substrates, and their self-assembly was demonstrated both on patterned silicon surfaces (88% correctly placed cubes), and to cube aggregates by complementary DNA

  8. Design optimization of a breast imaging system based on silicon microstrip detectors

    International Nuclear Information System (INIS)

    Stres, S.; Mikuz, M.

    2000-01-01

    A mammographic imaging set-up using silicon microstrip detectors in edge-on geometry was simulated using the GEANT package. Deposited energy in tissue of various thicknesses was evaluated and shown to agree to within 10% with reference calculations. Optimal energies as well as spectra for mammography with silicon detectors were determined by maximizing the figure of merit of a realistic imaging set-up. The scattered to primary radiation ratio was studied for various detector geometries. It was found that fan-shaped detectors are needed to maintain the image quality for divergent photon beams. (author)

  9. Encapsulated Silicon Nanocrystals Formed in Silica by Ion Beam Synthesis

    International Nuclear Information System (INIS)

    Choi, Han Woo; Woo, Hyung Joo; Kim, Joon Kon; Kim, Gi Dong; Hong, Wan; Ji, Young Yong

    2004-01-01

    The photoluminescence (PL) emission of Si nanocrystals synthesized by 400 keV Si ion implanted in SiO 2 is studied as a function of ion dose and annealing time. The formation of nanocrystals at around 600 nm from the surface was confirmed by RBS and HRTEM, and the Si nanocrystals showed a wide and very intense PL emission at 700-900 nm. The intensity of this emission showed a typical behaviour with a fast transitory increase to reach a saturation with the annealing time, however, the red shift increased continuously because of the Ostwald ripening. The oversaturation of dose derived a decrease of PL intensity because of the diminishment of quantum confinement. A strong enhancement of PL intensity by H passivation was confirmed also, and the possible mechanism is discussed

  10. Effect drug loading process on dissolution mechanism of encapsulated amoxicillin trihydrate in hydrogel semi-IPN chitosan methyl cellulose with pore forming agent KHCO3 as a floating drug delivery system

    Science.gov (United States)

    Fithawati, Garnis; Budianto, Emil

    2018-04-01

    Common treatment for Helicobacter pylori by repeated oral consumption of amoxicillin trihydrate is not effective. Amoxicillin trihydrate has a very short residence time in stomach which leads into its ineffectiveness. Residence time of amoxicillin trihydrate can be improved by encapsulating amoxicillin trihydrate into a floating drug delivery system. In this study, amoxicillin trihydrate is encapsulated into hydrogel semi-IPN chitosan methyl cellulose matrix as a floating drug delivery system and then treated with 20% KHCO3 as pore forming agent. Drug loading process used are in-situ loading and post loading. In-situ loading process has higher efficiency percentage and dissolution percentage than post loading process. In-situ loading process resulted 100% efficiency with 92,70% dissolution percentage. Post loading process resulted 98,7% efficiency with 90,42% dissolution percentage. Mechanism of drug dissolution study by kinetics approach showed both in-situ loading process and post loading process are diffusion and degradation process (n=0,4913) and (n=0,4602) respectively. These results are supported by characterization data from optical microscope and scanning electron microscopy (SEM). Data from optical microscope showed both loading process resulted in coarser hydrogel surface. Characterization using SEM showed elongated pores in both loading process after dissolution test.

  11. Hydrosilylated Porous Silicon Particles Function as an Intravitreal Drug Delivery System for Daunorubicin

    Science.gov (United States)

    Hartmann, Kathrin I.; Nieto, Alejandra; Wu, Elizabeth C.; Freeman, William R.; Kim, Jae Suk; Chhablani, Jay; Sailor, Michael J.

    2013-01-01

    Abstract Purpose To evaluate in vivo ocular safety of an intravitreal hydrosilylated porous silicon (pSi) drug delivery system along with the payload of daunorubicin (DNR). Methods pSi microparticles were prepared from the electrochemical etching of highly doped, p-type Si wafers and an organic linker was attached to the Si-H terminated inner surface of the particles by thermal hydrosilylation of undecylenic acid. DNR was bound to the carboxy terminus of the linker as a drug-loading strategy. DNR release from hydrosilylated pSi particles was confirmed in the excised rabbit vitreous using liquid chromatography–electrospray ionization–multistage mass spectrometry. Both empty and DNR-loaded hydrosilylated pSi particles were injected into the rabbit vitreous and the degradation and safety were studied for 6 months. Results The mean pSi particle size was 30×46×15 μm with an average pore size of 15 nm. Drug loading was determined as 22 μg per 1 mg of pSi particles. An ex vivo drug release study showed that intact DNR was detected in the rabbit vitreous. An in vivo ocular toxicity study did not reveal clinical or pathological evidence of any toxicity during a 6-month observation. Hydrosilylated pSi particles, either empty or loaded with DNR, demonstrated a slow elimination kinetics from the rabbit vitreous without ocular toxicity. Conclusions Hydrosilylated pSi particles can host a large quantity of DNR by a covalent loading strategy and DNR can be slowly released into the vitreous without ocular toxicity, which would appear if an equivalent quantity of free drug was injected. PMID:23448595

  12. The silicon chip: A versatile micro-scale platform for micro- and nano-scale systems

    Science.gov (United States)

    Choi, Edward

    Cutting-edge advances in micro- and nano-scale technology require instrumentation to interface with the external world. While technology feature sizes are continually being reduced, the size of experimentalists and their instrumentation do not mirror this trend. Hence there is a need for effective application-specific instrumentation to bridge the gap from the micro and nano-scale phenomena being studied to the comparative macro-scale of the human interfaces. This dissertation puts forward the idea that the silicon CMOS integrated circuit, or microchip in short, serves as an excellent platform to perform this functionality. The electronic interfaces designed for the semiconductor industry are particularly attractive as development platforms, and the reduction in feature sizes that has been a hallmark of the industry suggests that chip-scale instrumentation may be more closely coupled to the phenomena of interest, allowing finer control or improved measurement capabilities. Compatibility with commercial processes will further enable economies of scale through mass production, another welcome feature of this approach. Thus chip-scale instrumentation may replace the bulky, expensive, cumbersome-to-operate macro-scale prototypes currently in use for many of these applications. The dissertation examines four specific applications in which the chip may serve as the ideal instrumentation platform. These are nanorod manipulation, polypyrrole bilayer hinge microactuator control, organic transistor hybrid circuits, and contact fluorescence imaging. The thesis is structured around chapters devoted to each of these projects, in addition to a chapter on preliminary work on an RFID system that serves as a wireless interface model. Each of these chapters contains tools and techniques developed for chip-scale instrumentation, from custom scripts for automated layout and data collection to microfabrication processes. Implementation of these tools to develop systems for the

  13. The detector response simulation for the CBM silicon tracking system as a tool for hit error estimation

    Energy Technology Data Exchange (ETDEWEB)

    Malygina, Hanna [Goethe Universitaet Frankfurt (Germany); KINR, Kyiv (Ukraine); GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Darmstadt (Germany); Friese, Volker; Zyzak, Maksym [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Darmstadt (Germany); Collaboration: CBM-Collaboration

    2016-07-01

    The Compressed Baryonic Matter experiment(CBM) at FAIR is designed to explore the QCD phase diagram in the region of high net-baryon densities. As the central detector component, the Silicon Tracking System (STS) is based on double-sided micro-strip sensors. To achieve realistic modelling, the response of the silicon strip sensors should be precisely included in the digitizer which simulates a complete chain of physical processes caused by charged particles traversing the detector, from charge creation in silicon to a digital output signal. The current implementation of the STS digitizer comprises non-uniform energy loss distributions (according to the Urban theory), thermal diffusion and charge redistribution over the read-out channels due to interstrip capacitances. Using the digitizer, one can test an influence of each physical processes on hit error separately. We have developed a new cluster position finding algorithm and a hit error estimation method for it. Estimated errors were verified by the width of pull distribution (expected to be about unity) and its shape.

  14. Exergy analysis of encapsulation of photochromic dye by spray drying

    Science.gov (United States)

    Çay, A.; Akçakoca Kumbasar, E. P.; Morsunbul, S.

    2017-10-01

    Application of exergy analysis methodology for encapsulation of photochromic dyes by spray drying was presented. Spray drying system was investigated considering two subsystems, the heater and the dryer sections. Exergy models for each subsystem were proposed and exergy destruction rate and exergy efficiency of each subsystem and the whole system were computed. Energy and exergy efficiency of the system were calculated to be 5.28% and 3.40%, respectively. It was found that 90% of the total exergy inlet was destroyed during encapsulation by spray drying and the exergy destruction of the heater was found to be higher.

  15. Device for encapsulating radioactive materials

    International Nuclear Information System (INIS)

    Suthanthiran, K.

    1994-01-01

    A capsule for encapsulating radioactive material for radiation treatment comprising two or more interfitting sleeves, wherein each sleeve comprises a closed bottom portion having a circumferential wall extending therefrom, and an open end located opposite the bottom portion. The sleeves are constructed to fit over one another to thereby establish an effectively sealed capsule container. 3 figs

  16. Encapsulation of polymer photovoltaic prototypes

    DEFF Research Database (Denmark)

    Krebs, Frederik C

    2006-01-01

    A simple and efficient method for the encapsulation of polymer and organic photovoltaic prototypes is presented. The method employs device preparation on glass substrates with subsequent sealing using glass fiber reinforced thermosetting epoxy (prepreg) against a back plate. The method allows...

  17. Reactants encapsulation and Maillard Reaction

    NARCIS (Netherlands)

    Troise, A.D.; Fogliano, V.

    2013-01-01

    In the last decades many efforts have been addressed to the control of Maillard Reaction products in different foods with the aim to promote the formation of compounds having the desired color and flavor and to reduce the concentration of several potential toxic molecules. Encapsulation, already

  18. Technology of mammalian cell encapsulation

    NARCIS (Netherlands)

    Uludag, H; De Vos, P; Tresco, PA

    2000-01-01

    Entrapment of mammalian cells in physical membranes has been practiced since the early 1950s when it was originally introduced as a basic research tool. The method has since been developed based on the promise of its therapeutic usefulness in tissue transplantation. Encapsulation physically isolates

  19. Embedded atom approach for gold–silicon system from ab initio

    Indian Academy of Sciences (India)

    In the present paper, an empirical embedded atom method (EAM) potential for gold–silicon (Au–Si) is developed by fitting to ab initio force (the 'force matching' method) and experimental data. The force database is generated within ab initio molecular dynamics (AIMD). The database includes liquid phase at various ...

  20. A formulation to encapsulate nootkatone for tick control.

    Science.gov (United States)

    Behle, Robert W; Flor-Weiler, Lina B; Bharadwaj, Anuja; Stafford, Kirby C

    2011-11-01

    Nootkatone is a component of grapefruit oil that is toxic to the disease-vectoring tick, Ixodes scapularis Say, but unfortunately causes phytotoxicity to treated plants and has a short residual activity due to volatility. We prepared a lignin-encapsulated nootkatone formulation to compare with a previously used emulsifiable formulation for volatility, plant phytotoxicity, and toxicity to unfed nymphs of I. scapularis. Volatility of nootkatone was measured directly by trapping nootkatone vapor in a closed system and indirectly by measuring nootkatone residue on treated filter paper after exposure to simulated sunlight (Xenon). After 24 h in the closed system, traps collected only 15% of the nootkatone applied as the encapsulated formulation compared with 40% applied as the emulsifiable formulation. After a 1-h light exposure, the encapsulated formulation retained 92% of the nootkatone concentration compared with only 26% retained by the emulsifiable formulation. For plant phytotoxicity, cabbage, Brassica oleracea L., leaves treated with the encapsulated formulation expressed less necrosis, retaining greater leaf weight compared with leaves treated with the emusifiable formulation. The nootkatone in the emulsifiable formulation was absorbed by cabbage and oat, Avena sativa L., plants (41 and 60% recovered 2 h after application, respectively), as opposed to 100% recovery from the plants treated with encapsulated nootkatone. Using a treated vial technique, encapsulated nootkatone was significantly more toxic to I. scapularis nymphs (LC50 = 20 ng/cm2) compared with toxicity of the emulsifiable formulation (LC50 = 35 ng/cm2). Thus, the encapsulation of nootkatone improved toxicity for tick control, reduced nootkatone volatility, and reduced plant phytotoxicity.

  1. Encapsulation Processing and Manufacturing Yield Analysis

    Science.gov (United States)

    Willis, P.

    1985-01-01

    Evaluation of the ethyl vinyl acetate (EVA) encapsulation system is presented. This work is part of the materials baseline needed to demonstrate a 30 year module lifetime capability. Process and compound variables are both being studied along with various module materials. Results have shown that EVA should be stored rolled up, and enclosed in a plastic bag to retard loss of peroxide curing agents. The TBEC curing agent has superior shelf life and processing than the earlier Lupersol-101 curing agent. Analytical methods were developed to test for peroxide content, and experimental methodologies were formalized.

  2. Encapsulation of Hemin in Metal-Organic Frameworks for Catalyzing the Chemiluminescence Reaction of the H2O2-Luminol System and Detecting Glucose in the Neutral Condition.

    Science.gov (United States)

    Luo, Fenqiang; Lin, Yaolin; Zheng, Liyan; Lin, Xiaomei; Chi, Yuwu

    2015-06-03

    Novel metal-organic frameworks (MOFs) based solid catalysts have been synthesized by encapsulating Hemin into the HKUST-1 MOF materials. These have been first applied in the chemiluminescence field with outstanding performance. The functionalized MOFs not only maintain an excellent catalytic activity inheriting from Hemin but also can be cyclically utilized as solid mimic peroxidases in the neutral condition. The synthesized Hemin@HKUST-1 composites have been used to develop practical sensors for H2O2 and glucose with wide response ranges and low detection limits. It was envisioned that catalyst-functionalized MOFs for chemiluminescence sensing would have promising applications in green, selective, and sensitive detection of target analytes in the future.

  3. Influence of encapsulated functional lipids on crystal structure and chemical stability in solid lipid nanoparticles: Towards bioactive-based design of delivery systems.

    Science.gov (United States)

    Salminen, Hanna; Gömmel, Christina; Leuenberger, Bruno H; Weiss, Jochen

    2016-01-01

    We investigated the influence of physicochemical properties of encapsulated functional lipids--vitamin A, β-carotene and ω-3 fish oil--on the structural arrangement of solid lipid nanoparticles (SLN). The relationship between the crystal structure and chemical stability of the incorporated bioactive lipids was evaluated with different emulsifier compositions of a saponin-rich, food-grade Quillaja extract alone or combined with high-melting or low-melting lecithins. The major factors influencing the structural arrangement and chemical stability of functional lipids in solid lipid dispersions were their solubility in the aqueous phase and their crystallization temperature in relation to that of the carrier lipid. The results showed that the stabilization of the α-subcell crystals in the lattice of the carrier lipid is a key parameter for forming stable solid lipid dispersions. This study contributes to a better understanding of SLN as a function of the bioactive lipid. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Ion-beam-mixing in metal-metal systems and metal-silicon systems

    International Nuclear Information System (INIS)

    Hung, L.

    1984-01-01

    The influence of energetic ion bombardment on the composition and structure of thin film materials and utilization of ion-beam-mixing techniques to modify interfacial reactions are reported in this thesis. The phase formation in metals by using ion mixing techniques has been studied. Upon ion irradiation of Al/Pt, Al/Pd and Al/Ni thin films, only the simplest intermetallic compounds of PdAl and NiAl were formed in crystalline structure, while the amorphous phase has been observed over a large range of composition. Ion mixing of Au/Cu bilayers resulted in the formation of substitutional solid solutions with no trace of ordered compounds. The formation of the ordered compound CuAu was achieved either by irradiation of bilayers with Ar ions at elevated substrate temperature or by irradiation of the mixed layers with He ions at relatively low temperature. In the Au/Al system several crystal compounds existed in the as-deposited samples. These phases remained crystalline or transformed into other equilibrium compounds upon ion irradiation. The results suggest that the phase formation by ion mixing is dependent on the high quench rate in the collision cascade region and the atomic mobility at the irradiation temperature. The argument can be applied to silicide forming systems. With near-noble metals, the mixed atoms are mobile and form metallurgically distinct phases. With refractory metals, amorphous phases are formed due to lack of atomic mobility

  5. Research and development of photovoltaic power system. Interface studies of amorphous silicon; Taiyoko hatsuden system no kenkyu kaihatsu. Amorphous silicon kaimen no kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    Konagai, M [Tokyo Institute of Technology, Tokyo (Japan). Faculty of Engineering

    1994-12-01

    This paper reports the result obtained during fiscal 1994 on research on interface of amorphous silicon for solar cells. In research on amorphous solar cells using ZnO for transparent electrically conductive films, considerations were given on a growth mechanism of a ZnO film using the MOCVD process. It was made clear that the ZnO film grows with Zn(OH)2 working as a film forming species. It was also shown that the larger the ZnO particle size is, the more the solar cell efficiency is improved. Furthermore, theoretical elucidation was made on effects of rear face of an interface on cell characteristics, and experimental discussions were given subsequently. In research on solar cells using hydrogen diluted `i` layers, delta-doped solar cells were fabricated based on basic data obtained in the previous fiscal year, and the hydrogen dilution effect was evaluated from the cell characteristics. When the hydrogen dilution ratio is increased from zero to one, the conversion efficiency has improved from 12.2% to 12.6%. In addition, experiments and discussions were given on solar cells fabricated by using SiH2Cl2. 9 figs.

  6. Large-Scale PV Module Manufacturing Using Ultra-Thin Polycrystalline Silicon Solar Cells: Annual Subcontract Report, 1 April 2002--30 September 2003 (Revised)

    Energy Technology Data Exchange (ETDEWEB)

    Wohlgemuth, J.; Shea, S. P.

    2004-04-01

    The goal of BP Solar's Crystalline PVMaT program is to improve the present polycrystalline silicon manufacturing facility to reduce cost, improve efficiency, and increase production capacity. Key components of the program are: increasing ingot size; improving ingot material quality; improving material handling; developing wire saws to slice 100 ..mu..m thick silicon wafers on 200 ..mu..m centers; developing equipment for demounting and subsequent handling of very thin silicon wafers; developing cell processes using 100 ..mu..m thick silicon wafers that produce encapsulated cells with efficiencies of at least 15.4% at an overall yield exceeding 95%; expanding existing in-line manufacturing data reporting systems to provide active process control; establishing a 50 MW (annual nominal capacity) green-field Mega plant factory model template based on this new thin polycrystalline silicon technology; and facilitating an increase in the silicon feedstock industry's production capacity for lower-cost solar-grade silicon feedstock.

  7. The interaction of encapsulated pharmaceutical drugs with a silica matrix.

    Science.gov (United States)

    Morais, Everton C; Correa, Gabriel G; Brambilla, Rodrigo; Radtke, Claudio; Baibich, Ione Maluf; dos Santos, João Henrique Z

    2013-03-01

    A series of seven drugs, namely, fluoxetine, gentamicin, lidocaine, morphine, nifedipine, paracetamol and tetracycline, were encapsulated. The encapsulated systems were characterized using a series of complementary techniques: Fourier-transform infrared spectroscopy (FT-IR), diffusive reflectance spectroscopy in the UV-vis region (DRS) and X-ray photoelectron spectroscopy (XPS). According to the DRS spectra, most of the encapsulated systems showed a band shift of the maximum absorption when compared with the corresponding bare pharmaceutical. Additionally, after encapsulation, the drugs exhibited infrared band shifts toward higher wavenumbers, which in turn provided insight into potential sites for interaction with the silica framework. The amine group showed a band shift in the spectra of almost all the drugs (except nifedipine and tetracycline). This finding indicates the possibility of a hydrogen bonding interaction between the drug and the silica via electron donation from the amine group to the silica framework. XPS confirmed this interaction between the pharmaceuticals and the silica through the amine group. A correlation was observed between the textural characteristics of the solids and the spectroscopic data, suggesting that the amine groups from the pharmaceuticals were more perturbed upon encapsulation. Copyright © 2012 Elsevier B.V. All rights reserved.

  8. Islet and Stem Cell Encapsulation for Clinical Transplantation

    Science.gov (United States)

    Krishnan, Rahul; Alexander, Michael; Robles, Lourdes; Foster 3rd, Clarence E.; Lakey, Jonathan R.T.

    2014-01-01

    Over the last decade, improvements in islet isolation techniques have made islet transplantation an option for a certain subset of patients with long-standing diabetes. Although islet transplants have shown improved graft function, adequate function beyond the second year has not yet been demonstrated, and patients still require immunosuppression to prevent rejection. Since allogeneic islet transplants have experienced some success, the next step is to improve graft function while eliminating the need for systemic immunosuppressive therapy. Biomaterial encapsulation offers a strategy to avoid the need for toxic immunosuppression while increasing the chances of graft function and survival. Encapsulation entails coating cells or tissue in a semipermeable biocompatible material that allows for the passage of nutrients, oxygen, and hormones while blocking immune cells and regulatory substances from recognizing and destroying the cell, thus avoiding the need for systemic immunosuppressive therapy. Despite advances in encapsulation technology, these developments have not yet been meaningfully translated into clinical islet transplantation, for which several factors are to blame, including graft hypoxia, host inflammatory response, fibrosis, improper choice of biomaterial type, lack of standard guidelines, and post-transplantation device failure. Several new approaches, such as the use of porcine islets, stem cells, development of prevascularized implants, islet nanocoating, and multilayer encapsulation, continue to generate intense scientific interest in this rapidly expanding field. This review provides a comprehensive update on islet and stem cell encapsulation as a treatment modality in type 1 diabetes, including a historical outlook as well as current and future research avenues. PMID:25148368

  9. Monolithic amorphous silicon modules on continuous polymer substrate

    Energy Technology Data Exchange (ETDEWEB)

    Grimmer, D.P. (Iowa Thin Film Technologies, Inc., Ames, IA (United States))

    1992-03-01

    This report examines manufacturing monolithic amorphous silicon modules on a continuous polymer substrate. Module production costs can be reduced by increasing module performance, expanding production, and improving and modifying production processes. Material costs can be reduced by developing processes that use a 1-mil polyimide substrate and multilayers of low-cost material for the front encapsulant. Research to speed up a-Si and ZnO deposition rates is needed to improve throughputs. To keep throughput rates compatible with depositions, multibeam fiber optic delivery systems for laser scribing can be used. However, mechanical scribing systems promise even higher throughputs. Tandem cells and production experience can increase device efficiency and stability. Two alternative manufacturing processes are described: (1) wet etching and sheet handling and (2) wet etching and roll-to-roll fabrication.

  10. Fabrication of hemispherical liquid encapsulated structures based on droplet molding

    Science.gov (United States)

    Ishizuka, Hiroki; Miki, Norihisa

    2015-12-01

    We have developed and demonstrated a method for forming spherical structures of a thin polydimethylsiloxane (PDMS) membrane encapsulating a liquid. Liquid encapsulation can enhance the performance of microelectromechanical systems (MEMS) devices by providing deformability and improved dielectric properties. Parylene deposition and wafer bonding are applied to encapsulate liquid into a MEMS device. In parylene deposition, a parylene membrane is directly formed onto a liquid droplet. However, since the parylene membrane is stiff, the membrane is fragile. Although wafer bonding can encapsulate liquid between two substrates, the surface of the fabricated structure is normally flat. We propose a new liquid encapsulation method by dispensing liquid droplets. At first, a 20 μl PDMS droplet is dispensed on ethylene glycol. A 70 μl glycerin droplet is dispensed into a PDMS casting solution layer. The droplet forms a layer on heated ethylene glycol. Glycerin and ethylene glycol are chosen for their high boiling points. Additionally, a glycerin droplet is dispensed on the layer and surrounded by a thin PDMS casting solution film. The film is baked for 1 h at 75 °C. As the result, a structure encapsulating a liquid in a flexible PDMS membrane is obtained. We investigate the effects of the volume, surface tension, and guide thickness on the shape of the formed structures. We also evaluated the effect of the structure diameter on miniaturization. The structure can be adapted for various functions by changing the encapsulated liquid. We fabricated a stiffness-tunable structure by dispensing a magnetorheoligical fluid droplet with a stiffness that can be changed by an external magnetic field. We also confirmed that the proposed structure can produce stiffness differences that are distinguishable by humans.

  11. A digital X-ray imaging system based on silicon strip detectors working in edge-on configuration

    Energy Technology Data Exchange (ETDEWEB)

    Bolanos, L. [CEADEN, Calle 30 502 e/ 5ta y 7ma Avenida, Playa, Ciudad Habana (Cuba); Boscardin, M. [IRST, Fondazione Bruno Kessler, Via Sommarive 18, Povo, 38100 Trento (Italy); Cabal, A.E. [CEADEN, Calle 30 502 e/ 5ta y 7ma Avenida, Playa, Ciudad Habana (Cuba); Diaz, M. [InSTEC, Ave. Salvador Allende esq. Luaces, Quinta de los Molinos, Ciudad Habana (Cuba); Grybos, P.; Maj, P. [Faculty of Electrical Engineering, Automatics, Computer Science and Electronics, Department of Measurement and Instrumentation, AGH University of Science and Technology, Al. Mickiewicza 30, 30-059 Cracow (Poland); Prino, F. [Istituto Nazionale di Fisica Nucleare, Sezione di Torino, Via P. Giuria 1, 10125 Torino (Italy); Ramello, L. [Dipartimento di Scienze e Tecnologie Avanzate, Universita del Piemonte Orientale, Via T. Michel 11, 15100 Alessandria (Italy)], E-mail: luciano.ramello@mfn.unipmn.it; Szczygiel, R. [Faculty of Electrical Engineering, Automatics, Computer Science and Electronics, Department of Measurement and Instrumentation, AGH University of Science and Technology, Al. Mickiewicza 30, 30-059 Cracow (Poland)

    2009-09-21

    We present the energy resolution and imaging performance of a digital X-ray imaging system based on a 512-strip silicon strip detector (SSD) working in the edge-on configuration. The SSDs tested in the system are 300 {mu}m thick with 1 or 2-cm-long strips and 100 {mu}m pitch. To ensure a very small dead area of the SSD working in edge-on configuration, the detector is cut perpendicular to the strips at a distance of only 20 {mu}m from the end of the strips. The 512-strip silicon detector is read out by eight 64-channel integrated circuits called DEDIX [Grybos et al., IEEE Trans. Nucl. Sci. NS-54 (2007) 1207]. The DEDIX IC operates in a single photon counting mode with two independent amplitude discriminators per channel. The readout electronic channel connected to a detector with effective input capacitance of about 2 pF has an average equivalent noise charge (ENC) of about 163 el. rms and is able to count 1 Mcps of average rate of input pulses. The system consisting of 512 channels has an excellent channel-to-channel uniformity-the effective threshold spread calculated to the charge-sensitive amplifier inputs is 12 el. rms (at one sigma level). With this system a few test images of a phantom have been taken in the 10-30 keV energy range.

  12. Encapsulated microenergetic material

    Energy Technology Data Exchange (ETDEWEB)

    Roberts, Jeffery James; Aines, Roger D.; Duoss, Eric B.; Spadaccini, Christopher M.; Vandersall, Kevin S.

    2017-02-07

    Providing high energy materials that can be placed in previously created fractures and activating them in place to extend or change an existing fracture system. Also detecting the location of fractures or permeable pathways and a means to assess the extent and efficiency of proppant emplacement.

  13. Encapsulated microenergetic material

    Energy Technology Data Exchange (ETDEWEB)

    Roberts, Jeffery James; Aines, Roger D.; Duoss, Eric B.; Spadaccini, Christopher M.; Vandersall, Kevin S.

    2018-02-20

    Providing high energy materials that can be placed in previously created fractures and activating them in place to extend or change an existing fracture system. Also detecting the location of fractures or permeable pathways and a means to assess the extent and efficiency of proppant emplacement.

  14. The upgrade of the ALICE Inner Tracking System - Status of the R&D; on monolithic silicon pixel sensors

    OpenAIRE

    Van Hoorne, Jacobus Willem

    2014-01-01

    s a major part of its upgrade plans, the ALICE experiment schedules the installation of a novel Inner Tracking System (ITS) during the Long Shutdown 2 (LS2) of the LHC in 2018/19. It will replace the present silicon tracker with seven layers of Monolithic Active Pixel Sensors (MAPS) and significantly improve the detector performance in terms of tracking and rate capabilities. The choice of technology has been guided by the tight requirements on the material budget of 0 : 3 % X = X 0 /layer fo...

  15. A low cost and hybrid technology for integrating silicon sensors or actuators in polymer microfluidic systems

    International Nuclear Information System (INIS)

    Charlot, Samuel; Gué, Anne-Marie; Tasselli, Josiane; Marty, Antoine; Abgrall, Patrick; Estève, Daniel

    2008-01-01

    This paper describes a new technology permitting a hybrid integration of silicon chips in polymer (PDMS and SU8) microfluidic structures. This two-step technology starts with transferring the silicon device onto a rigid substrate (typically PCB) and planarizing it, and then it proceeds with stacking of the polymer-made fluidic network onto the device. The technology is low cost, based on screen printing and lamination, can be applied to treat large surface areas, and is compatible with standard photolithography and vacuum based approaches. We show, as an example, the integration of a thermal sensor inside channels made of PDMS or SU8. The developed structures had no fluid leaks at the Si/polymer interfaces and the electrical circuit was perfectly tightproof. (note)

  16. Surface nanostructuring in the carbon–silicon(100) system upon microwave plasma treatment

    Energy Technology Data Exchange (ETDEWEB)

    Yafarov, R. K., E-mail: pirpc@yandex.ru; Shanygin, V. Ya. [Russian Academy of Sciences, Kotel’nikov Institute of Radio Engineering and Electronics, Saratov Branch (Russian Federation)

    2017-04-15

    The study is concerned with the physical and chemical processes and the mechanisms of the effect of plasma preparation of a surface on the systematic features of condensation and surface phase transformations during the formation of Si–C mask domains on p-Si(100) crystals by the deposition of submonolayer C coatings in the microwave plasma of low-pressure ethanol vapors. It is shown that, at short durations of the deposition of carbon onto silicon wafers with a natural-oxide coating at a temperature of 100°C, the formation of domains is observed. The lateral dimensions of the domains lie in the range from 10–15 to 200 nm, and the heights of ridges produced by the plasma chemical etching of silicon through the mask domain coatings vary in the range from 40 to 80 nm.

  17. SISTEM PENGOLAHAN AIR ASAM TAMBANG PADA WATER POND DAN APLIKASI MODEL ENCAPSULATION IN-PIT DISPOSAL PADA WASTE DUMP TAMBANG BATUBARA (Acid Mine Drainage Treatment System in Water Pond and Application of Encapsulation In-Pit Disposal Model in Waste Dump

    Directory of Open Access Journals (Sweden)

    Andy R. Erwin Wijaya

    2010-03-01

    . The control system of acid mine drainage contamination included treatment of acid mine drainage into water pond and management of oxide/benign waste on the waste dump. Treatment method is neutralization of acid mine drainage into water pond using alkali reagent. The most effective and economic alkali reagent is limestone. Amount of limestone needed to neutralize of acid mine drainage (5040 m3 into water pond is 104.56 kg. The management of oxide/benign waste is application of encapsulation in-pit disposal model. This model is more effective to prevent acid mine drainage formed. Cover materials are often clay subsoils and have been used for covering to prevent oxidation. The clay have high compaction rates and low permeability (2.3148 x 10-9 m/s and this material is sufficient availability.

  18. Analysis of Double-encapsulated Fuel Rods

    Energy Technology Data Exchange (ETDEWEB)

    Hales, Jason Dean [Idaho National Laboratory; Medvedev, Pavel G [Idaho National Laboratory; Novascone, Stephen Rhead [Idaho National Laboratory; Perez, Danielle Marie [Idaho National Laboratory; Williamson, Richard L [Idaho National Laboratory

    2014-09-01

    In an LWR fuel rod, the cladding encapsulates the fuel, contains fission products, and transfers heat directly to the water coolant. In some situations, it may be advantageous to separate the cladding from the coolant through use of a secondary cladding or capsule. This may be done to increase confidence that the fuel or fission products will not mix with the coolant, to provide a mechanism for controlling the rod temperature, or to place multiple experimental rodlets within a single housing. With an axisymmetric assumption, it is possible to derive closed-form expressions for the temperature profile in a fuel rod using radially-constant thermal conductivity in the fuel. This is true for both a traditional fuel-cladding rod and a double-encapsulated fuel (fuel, cladding, capsule) configuration. Likewise, it is possible to employ a fuel performance code to analyse both a traditional and a double-encapsulated fuel. In the case of the latter, two sets of gap heat transfer conditions must be imposed. In this work, we review the equations associated with radial heat transfer in a cylindrical system, present analytic and computational results for a postulated power and gas mixture history for IFA-744, and describe the analysis of the AFC-2A, 2B metallic fuel alloy experiments at the Advanced Test Reactor, including the effect of a release of fission products into the cladding-capsule gap. The computational results for these two cases were obtained using BISON, a fuel performance code under development at Idaho National Laboratory.

  19. Process engineering of high voltage alginate encapsulation of mesenchymal stem cells

    International Nuclear Information System (INIS)

    Gryshkov, Oleksandr; Pogozhykh, Denys; Zernetsch, Holger; Hofmann, Nicola; Mueller, Thomas; Glasmacher, Birgit

    2014-01-01

    Encapsulation of stem cells in alginate beads is promising as a sophisticated drug delivery system in treatment of a wide range of acute and chronic diseases. However, common use of air flow encapsulation of cells in alginate beads fails to produce beads with narrow size distribution, intact spherical structure and controllable sizes that can be scaled up. Here we show that high voltage encapsulation (≥ 15 kV) can be used to reproducibly generate spherical alginate beads (200–400 μm) with narrow size distribution (± 5–7%) in a controlled manner under optimized process parameters. Flow rate of alginate solution ranged from 0.5 to 10 ml/h allowed producing alginate beads with a size of 320 and 350 μm respectively, suggesting that this approach can be scaled up. Moreover, we found that applied voltages (15–25 kV) did not alter the viability and proliferation of encapsulated mesenchymal stem cells post-encapsulation and cryopreservation as compared to air flow. We are the first who employed a comparative analysis of electro-spraying and air flow encapsulation to study the effect of high voltage on alginate encapsulated cells. This report provides background in application of high voltage to encapsulate living cells for further medical purposes. Long-term comparison and work on alginate–cell interaction within these structures will be forthcoming. - Highlights: • High voltage alginate encapsulation of mesenchymal stem cells (MSCs) was designed. • Reproducible and spherical alginate beads were generated via high voltage. • Air flow encapsulation was utilized as a comparative approach to high voltage. • High voltage did not alter the viability and proliferation of encapsulated MSCs. • High voltage encapsulation can be scaled up and applied in cell-based therapy

  20. Development of test models to quantify encapsulated bioburden in spacecraft polymer materials by cultivation-dependent and molecular methods

    Science.gov (United States)

    Bauermeister, Anja; Moissl-Eichinger, Christine; Mahnert, Alexander; Probst, Alexander; Flier, Niwin; Auerbach, Anna; Weber, Christina; Haberer, Klaus; Boeker, Alexander

    Bioburden encapsulated in spacecraft polymers (such as adhesives and coatings) poses a potential risk to scientific exploration of other celestial bodies, but it is not easily detectable. In this study, we developed novel testing strategies to estimate the quantity of intrinsic encapsulated bioburden in polymers used frequently on spaceflight hardware. In particular Scotch-Weld (TM) 2216 B/A (Epoxy adhesive); MAP SG121FD (Silicone coating), Solithane (®) 113 (Urethane resin); ESP 495 (Silicone adhesive); and Dow Corning (®) 93-500 (Silicone encapsulant) were investigated. As extraction of bioburden from polymerized (solid) materials did not prove feasible, a method was devised to extract contaminants from uncured polymer precursors by dilution in organic solvents. Cultivation-dependent analyses showed less than 0.1-2.5 colony forming units (cfu) per cm³ polymer, whereas quantitative PCR with extracted DNA indicated considerably higher values, despite low DNA extraction efficiency. Results obtained by this method reflected the most conservative proxy for encapsulated bioburden. To observe the effect of physical and chemical stress occurring during polymerization on the viability of encapsulated contaminants, Bacillus safensis spores were embedded close to the surface in cured polymer, which facilitated access for different analytical techniques. Staining by AlexaFluor succinimidyl ester 488 (AF488), propidium monoazide (PMA), CTC (5-cyano-2,3-diotolyl tetrazolium chloride) and subsequent confocal laser scanning microscopy (CLSM) demonstrated that embedded spores retained integrity, germination and cultivation ability even after polymerization of the adhesive Scotch-Weld™ 2216 B/A.

  1. Encapsulation of polymer photovoltaic prototypes

    Energy Technology Data Exchange (ETDEWEB)

    Krebs, Frederik C. [The Danish Polymer Centre, RISOE National Laboratory, P.O. Box 49, DK-4000 Roskilde (Denmark)

    2006-12-15

    A simple and efficient method for the encapsulation of polymer and organic photovoltaic prototypes is presented. The method employs device preparation on glass substrates with subsequent sealing using glass fiber reinforced thermosetting epoxy (prepreg) against a back plate. The method allows for transporting oxygen and water sensitive devices outside a glove box environment after sealing and enables sharing of devices between research groups such that efficiency and stability can be evaluated in different laboratories. (author)

  2. Zeolite encapsulation of H2

    International Nuclear Information System (INIS)

    Cooper, S.; Lakner, J.F.

    1982-08-01

    Experiments with H 2 have shown that it is possible to encapsulate gases in the structure of certain molecular sieves. This method may offer a better means of temporarily storing and disposing of tritium over some others presently in use. The method may also prove safer, and may enable isotope separation, and removal of 3 He. Initial experiments were performed with H 2 to screen potential candidates for use with tritium

  3. Implementation of a Large Scale Control System for a High-Energy Physics Detector: The CMS Silicon Strip Tracker

    CERN Document Server

    Masetti, Lorenzo; Fischer, Peter

    2011-01-01

    Control systems for modern High-Energy Physics (HEP) detectors are large distributed software systems managing a significant data volume and implementing complex operational procedures. The control software for the LHC experiments at CERN is built on top of a commercial software used in industrial automation. However, HEP specific requirements call for extended functionalities. This thesis focuses on the design and implementation of the control system for the CMS Silicon Strip Tracker but presents some general strategies that have been applied in other contexts. Specific design solutions are developed to ensure acceptable response times and to provide the operator with an effective summary of the status of the devices. Detector safety is guaranteed by proper configuration of independent hardware systems. A software protection mechanism is used to avoid the widespread intervention of the hardware safety and to inhibit dangerous commands. A wizard approach allows non expert operators to recover error situations...

  4. Antioxidant Effects of Quercetin and Catechin Encapsulated into PLGA Nanoparticles

    Directory of Open Access Journals (Sweden)

    Hector Pool

    2012-01-01

    Full Text Available Polymeric nanoparticles (PLGA have been developed for the encapsulation and controlled release of quercetin and catechin. Nanoparticles were fabricated using a solvent displacement method. Physicochemical properties were measured by light scattering, scanning electron microscopy and ζ-potential, X-ray diffraction, infrared spectroscopy and differential scanning calorimetry. Encapsulation efficiency and in vitro release profiles were obtained from differential pulse voltammetry experiments. Antioxidant properties of free and encapsulated flavonoids were determined by TBARS, fluorescence spectroscopy and standard chelating activity methods. Relatively small (d≈ 400 nm polymeric nanoparticles were obtained containing quercetin or catechin in a non-crystalline form (EE ≈ 79% and the main interactions between the polymer and each flavonoid were found to consist of hydrogen bonds. In vitro release profiles were pH-dependant, the more acidic pH, the faster release of each flavonoid from the polymeric nanoparticles. The inhibition of the action of free radicals and chelating properties, were also enhanced when quercetin and catechin were encapsulated within PLGA nanoparticles. The information obtained from this study will facilitate the design and fabrication of polymeric nanoparticles as possible oral delivery systems for encapsulation, protection and controlled release of flavonoids aimed to prevent oxidative stress in human body or food products.

  5. Tracing the origin of dissolved silicon transferred from various soil-plant systems towards rivers: a review

    Directory of Open Access Journals (Sweden)

    J.-T. Cornelis

    2011-01-01

    Full Text Available Silicon (Si released as H4SiO4 by weathering of Si-containing solid phases is partly recycled through vegetation before its land-to-rivers transfer. By accumulating in terrestrial plants to a similar extent as some major macronutrients (0.1–10% Si dry weight, Si becomes largely mobile in the soil-plant system. Litter-fall leads to a substantial reactive biogenic silica pool in soil, which contributes to the release of dissolved Si (DSi in soil solution. Understanding the biogeochemical cycle of silicon in surface environments and the DSi export from soils into rivers is crucial given that the marine primary bio-productivity depends on the availability of H4SiO4 for phytoplankton that requires Si. Continental fluxes of DSi seem to be deeply influenced by climate (temperature and runoff as well as soil-vegetation systems. Therefore, continental areas can be characterized by various abilities to transfer DSi from soil-plant systems towards rivers. Here we pay special attention to those processes taking place in soil-plant systems and controlling the Si transfer towards rivers. We aim at identifying relevant geochemical tracers of Si pathways within the soil-plant system to obtain a better understanding of the origin of DSi exported towards rivers. In this review, we compare different soil-plant systems (weathering-unlimited and weathering-limited environments and the variations of the geochemical tracers (Ge/Si ratios and δ30Si in DSi outputs. We recommend the use of biogeochemical tracers in combination with Si mass-balances and detailed physico-chemical characterization of soil-plant systems to allow better insight in the sources and fate of Si in these biogeochemical systems.

  6. Encapsulation of pancreatic islets for transplantation in diabetes : the untouchable islets

    NARCIS (Netherlands)

    de Vos, P; Marchetti, P

    The aim of encapsulation of pancreatic islets is to transplant in the absence of immunosuppression. It is based on the principle that transplanted tissue is protected from the host immune system by an artificial membrane. Encapsulation allows for application of insulin-secreting cells of animal or

  7. Silicon germanium mask for deep silicon etching

    KAUST Repository

    Serry, Mohamed

    2014-07-29

    Polycrystalline silicon germanium (SiGe) can offer excellent etch selectivity to silicon during cryogenic deep reactive ion etching in an SF.sub.6/O.sub.2 plasma. Etch selectivity of over 800:1 (Si:SiGe) may be achieved at etch temperatures from -80 degrees Celsius to -140 degrees Celsius. High aspect ratio structures with high resolution may be patterned into Si substrates using SiGe as a hard mask layer for construction of microelectromechanical systems (MEMS) devices and semiconductor devices.

  8. Silicon germanium mask for deep silicon etching

    KAUST Repository

    Serry, Mohamed; Rubin, Andrew; Refaat, Mohamed; Sedky, Sherif; Abdo, Mohammad

    2014-01-01

    Polycrystalline silicon germanium (SiGe) can offer excellent etch selectivity to silicon during cryogenic deep reactive ion etching in an SF.sub.6/O.sub.2 plasma. Etch selectivity of over 800:1 (Si:SiGe) may be achieved at etch temperatures from -80 degrees Celsius to -140 degrees Celsius. High aspect ratio structures with high resolution may be patterned into Si substrates using SiGe as a hard mask layer for construction of microelectromechanical systems (MEMS) devices and semiconductor devices.

  9. Interim report of the DOE [Department of Energy] Type B Investigation Group: Cesium-137, a systems evaluation, encapsulation to release at Radiation Sterilizers, Inc., Decatur, Georgia

    International Nuclear Information System (INIS)

    Hultgren, R.O.

    1990-07-01

    Sometime between April 28, 1988, and June 5, 1988, a 22-inch long by 2.625-inch diameter doubly encapsulated cesium-137 irradiation source began leaking in the RSI-Decatur, Georgia, irradiation facility. By November 1988 when the source was isolated, between 7 and 8 curies (0.4 grams) leaked. This source was one of 1576 produced at Hanford to isolate the highly radioactive elements of wastes stored in single-walled tanks there. The capsule was designed for long term storage in a benign controlled pool environment on the Hanford reservation. This investigation evaluates the cause of the incident, the management and administrative matters including leasing and licensing, the capable design and manufacture, and the capsule qualification process. As a result, only two post-incident activities are discussed in the report. The first is the administrative characteristics of the early incident response, and the second is the results of the evaluation to date of the failed and other capsules from the RSI facility. 11 figs., 10 tabs

  10. Silicon photonics fundamentals and devices

    CERN Document Server

    Deen, M Jamal

    2012-01-01

    The creation of affordable high speed optical communications using standard semiconductor manufacturing technology is a principal aim of silicon photonics research. This would involve replacing copper connections with optical fibres or waveguides, and electrons with photons. With applications such as telecommunications and information processing, light detection, spectroscopy, holography and robotics, silicon photonics has the potential to revolutionise electronic-only systems. Providing an overview of the physics, technology and device operation of photonic devices using exclusively silicon and related alloys, the book includes: * Basic Properties of Silicon * Quantum Wells, Wires, Dots and Superlattices * Absorption Processes in Semiconductors * Light Emitters in Silicon * Photodetectors , Photodiodes and Phototransistors * Raman Lasers including Raman Scattering * Guided Lightwaves * Planar Waveguide Devices * Fabrication Techniques and Material Systems Silicon Photonics: Fundamentals and Devices outlines ...

  11. Charge transfer in conjugated oligomers encapsulated into carbon nanotubes

    Energy Technology Data Exchange (ETDEWEB)

    Almadori, Y.; Alvarez, L.; Michel, T.; Le Parc, R.; Bantignies, J.L.; Hermet, P.; Sauvajol, J.L. [Laboratoire Charles Coulomb UMR 5521, Universite Montpellier 2, 34095 Montpellier (France); Laboratoire Charles Coulomb UMR 5521, CNRS, 34095 Montpellier (France); Arenal, R. [Laboratoire d' Etude des Microstructures, CNRS-ONERA, 92322 Chatillon (France); Laboratorio de Microscopias Avanzadas, Instituto de Nanociencia de Aragon, U. Zaragoza, 50018 Zaragoza (Spain); Babaa, R. [Laboratoire de Chimie des Surfaces et Interfaces, CEA, IRAMIS, SPCSI, 91191 Gif-sur-Yvette Cedex (France); Chemical Engineering Department, University of Technology PETRONAS, UTP, Ipoh-Perak (Malaysia); Jouselme, B.; Palacin, S. [Laboratoire de Chimie des Surfaces et Interfaces, CEA, IRAMIS, SPCSI, 91191 Gif-sur-Yvette Cedex (France)

    2011-11-15

    This study deals with a hybrid system consisting in quaterthiophene derivative encapsulated inside single-walled and multi-walled carbon nanotubes. Investigations of the encapsulation step are performed by transmission electron microscopy. Raman spectroscopy data point out different behaviors depending on the laser excitation energy with respect to the optical absorption of quaterthiophene. At low excitation energy (far from the oligomer resonance window) there is no significant modification of the Raman spectra before and after encapsulation. By contrast, at high excitation energy (close to the oligomer resonance window), Raman spectra exhibit a G-band shift together with an important RBM intensity loss, suggesting a significant charge transfer between the inserted molecule and the host nanotubes. Those results suggest a photo induced process leading to a significant charge transfer. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  12. Spent LWR fuel encapsulation and dry storage demonstration

    International Nuclear Information System (INIS)

    Bahorich, R.J.; Durrill, D.C.; Cross, T.E.; Unterzuber, R.

    1980-01-01

    In 1977 the Spent Fuel Handling and Packaging Program (SFHPP) was initiated by the Department of Energy to develop and test the capability to satisfactorily encapsulate typical spent fuel assemblies from commercial light-water nuclear power plants and to establish the suitability of one or more surface and near surface concepts for the interim dry storage of the encapsulated spent fuel assemblies. The E-MAD Facility at the Nevada Test Site, which is operated for the Department of Energy by the Advanced Energy Systems Division (AESD) of the Westinghouse Electric Corporation, was chosen as the location for this demonstration because of its extensive existing capabilities for handling highly radioactive components and because of the desirable site characteristics for the proposed storage concepts. This paper describes the remote operations related to the process steps of handling, encapsulating and subsequent dry storage of spent fuel in support of the Demonstration Program

  13. Efficient Asymmetric Index Encapsulation Scheme for Anonymous Content Centric Networking

    Directory of Open Access Journals (Sweden)

    Rong Ma

    2017-01-01

    Full Text Available Content Centric Networking (CCN is an effective communication paradigm that well matches the features of wireless environments. To be considered a viable candidate in the emerging wireless networks, despite the clear benefits of location-independent security, CCN must at least have parity with existing solutions for confidential and anonymous communication. This paper designs a new cryptographic scheme, called Asymmetric Index Encapsulation (AIE, that enables the router to test whether an encapsulated header matches the token without learning anything else about both of them. We suggest using the AIE as the core protocol of anonymous Content Centric Networking. A construction of AIE which strikes a balance between efficiency and security is given. The scheme is proved to be secure based on the DBDH assumption in the random oracle with tight reduction, while the encapsulated header and the token in our system consist of only three elements.

  14. Hot dewatering and resin encapsulation of intermediate level radioactive waste

    International Nuclear Information System (INIS)

    Rickman, J.; Birch, D.

    1985-01-01

    The chemistry of the processes involved in the hot dewatering and encapsulation of alumino-ferric hydroxide floc in epoxide resin have been studied. Pretreatment of the floc to reduce resin attack and hydrolysis and to increase the dimensional stability of the solidified wasteform has been evaluated. It has been demonstrated that removal of ammonium nitrate from the floc and control of the residual water in the resin are important factors in ensuring dimensional stability of the solidified resin. Resin systems have been identified which, together with the appropriate waste pretreatment have successfully encapsulated a simulated magnox sludge producing a stable wasteform having mechanical and physical properties comparable with the basic resin. (author)

  15. Surface Passivation of Silicon Using HfO2 Thin Films Deposited by Remote Plasma Atomic Layer Deposition System.

    Science.gov (United States)

    Zhang, Xiao-Ying; Hsu, Chia-Hsun; Lien, Shui-Yang; Chen, Song-Yan; Huang, Wei; Yang, Chih-Hsiang; Kung, Chung-Yuan; Zhu, Wen-Zhang; Xiong, Fei-Bing; Meng, Xian-Guo

    2017-12-01

    Hafnium oxide (HfO 2 ) thin films have attracted much attention owing to their usefulness in equivalent oxide thickness scaling in microelectronics, which arises from their high dielectric constant and thermodynamic stability with silicon. However, the surface passivation properties of such films, particularly on crystalline silicon (c-Si), have rarely been reported upon. In this study, the HfO 2 thin films were deposited on c-Si substrates with and without oxygen plasma pretreatments, using a remote plasma atomic layer deposition system. Post-annealing was performed using a rapid thermal processing system at different temperatures in N 2 ambient for 10 min. The effects of oxygen plasma pretreatment and post-annealing on the properties of the HfO 2 thin films were investigated. They indicate that the in situ remote plasma pretreatment of Si substrate can result in the formation of better SiO 2 , resulting in a better chemical passivation. The deposited HfO 2 thin films with oxygen plasma pretreatment and post-annealing at 500 °C for 10 min were effective in improving the lifetime of c-Si (original lifetime of 1 μs) to up to 67 μs.

  16. Development of thin film encapsulation process for piezoresistive MEMS gyroscope with wide gaps

    Science.gov (United States)

    Ayanoor-Vitikkate, Vipin

    The gyroscope is an inertial sensor used to measure the angular rate of a rotating object. This helps to determine the pitch and yaw rate of any moving body. A number of applications have been developed for consumer and automotive markets, for e.g. vehicle stability control, navigation assist, roll over detection. These are primarily used in high-end cars, where cost is not a major factor. Other areas where a MEMS Gyro can be used are robotics, camcorder stabilization, virtual reality, and more. Primarily due to cost and the size most of these applications have not reached any significant volume. One reason for this is the relatively high cost of MEMS gyros compared to other MEMS sensors like accelerometers or pressure sensors. Generally the cost of packaging a MEMS sensor is about 85-90% of the total cost. Currently most MEMS based gyroscopes are made using bulk or surface micromachining, after which they are packaged using wafer bonding. This unfortunately leads to wastage of silicon and increase in the package size, thus reducing the yield. One way to reduce the cost of packaging is by wafer scale thin film encapsulation of MEMS gyroscopes. The goal of the present work is to fabricate a rate grade MEMS gyroscope and encapsulate it by modifying an existing thin-film encapsulation technique. Packaging is an important step towards commercialization of the device and we plan to use thin wafer scale encapsulation technique developed previously in our group to package these devices. The silicon micro machined gyroscope will be fabricated on SOI (Silicon-on-Insulator) wafers using Bosch DRIE etching techniques. The encapsulation of the device is carried out using epitaxial polysilicon in order to provide a high vacuum inside the device chamber. The advantages offered by this technique are the reduction in area of the die and thus less silicon surface is wasted. In addition to this the encapsulation technique helps in creating a vacuum inside the micro device, which

  17. Viscous effects in liquid encapsulated liquid bridges

    International Nuclear Information System (INIS)

    Johnson, Duane T.

    2002-01-01

    An analytical derivation of the surface deflections and the streamfunctions for the flow inside a liquid encapsulated liquid bridge has been derived using an asymptotic expansion about a small capillary number. The model assumes an initially flat and cylindrical interface under the assumption that the densities of both fluids are equal. To simplify the analysis, the top and bottom walls are assumed to be stress-free and the Reynolds number is assumed to be negligible. Flow is generated either by a moving outer wall (shear-driven flow) or by applying a temperature difference across the top and bottom walls (Marangoni-driven flow). The resulting equations show that for the shear-driven flow, as the viscosity ratio increases, the surface deflections increase monotonically. For the Marangoni-driven flow there exist values of the viscosity ratio where the surface deflections reach a minimum and then switch signs. This investigation shows that it may be possible in more realistic systems to use an outer encapsulating liquid of the proper viscosity ratio to stabilize the liquid-liquid interface during float zone crystal growth

  18. Silicon-Based Technology for Integrated Waveguides and mm-Wave Systems

    DEFF Research Database (Denmark)

    Jovanovic, Vladimir; Gentile, Gennaro; Dekker, Ronald

    2015-01-01

    IC processing is used to develop technology for silicon-filled millimeter-wave-integrated waveguides. The front-end process defines critical waveguide sections and enables integration of dedicated components, such as RF capacitors and resistors. Wafer gluing is used to strengthen the mechanical...... support and deep reactive-ion etching forms the waveguide bulk with smooth and nearly vertical sidewalls. Aluminum metallization covers the etched sidewalls, fully enclosing the waveguides in metal from all sides. Waveguides are fabricated with a rectangular cross section of 560 μm x 280 μm. The measured...

  19. Historical Evidence of Importance to the Industrialization of Flat-plate Silicon Photovoltaic Systems, Volume 2

    Science.gov (United States)

    Smith, J. L.; Gates, W. R.; Lee, T.

    1978-01-01

    Problems which may arise as the low cost silicon solar array (LSSA) project attempts to industrialize the production technologies are defined. The charge to insure an annual production capability of 500 MW peak for the photovoltaic supply industry by 1986 was critically examined, and focused on one of the motivations behind this goal-concern over the timely development of industrial capacity to supply anticipated demand. Conclusions from the analysis are utilized in a discussion of LSSA's industrialization plans, particularly the plans for pilot, demonstration and commercial scale production plants. Specific recommendations for the implementation of an industrialization task and the disposition of the project quantity goal were derived.

  20. Solar photovoltaic research and development program of the Air Force Aero Propulsion Laboratory. [silicon solar cell applicable to satellite power systems

    Science.gov (United States)

    Wise, J.

    1979-01-01

    Progress is reported in the following areas: laser weapon effects, solar silicon solar cell concepts, and high voltage hardened, high power system technology. Emphasis is placed on solar cells with increased energy conversion efficiency and radiation resistance characteristics for application to satellite power systems.

  1. Alginate-hydroxypropylcellulose hydrogel microbeads for alkaline phosphatase encapsulation

    NARCIS (Netherlands)

    Karewicz, A.; Zasada, K.; Bielska, D.; Douglas, T.E.L.; Jansen, J.A.; Leeuwenburgh, S.C.G.; Nowakowska, M.

    2014-01-01

    There is a growing interest in using proteins as therapeutics agents. Unfortunately, they suffer from limited stability and bioavailability. We aimed to develop a new delivery system for proteins. ALP, a model protein, was successfully encapsulated in the physically cross-linked sodium

  2. P-111 : a thin film encapsulation stack for PLED and OLED displays

    NARCIS (Netherlands)

    Assche, van F.J.H.; Vangheluwe, R.T.; Maes, J.W.C.; Mischke, W.S.; Bijker, M.D.; Dings, F.C.; Evers, M.F.J.; Kessels, W.M.M.; Sanden, van de M.C.M.

    2004-01-01

    For a thin film (<1 µm) encapsulation stack consisting of only 3 plasma deposited silicon nitride layers separated by a thin (<100 nm) organic layer, a water permeation rate of below 10–5 g/m2 per day at 50 °C and 50% rH has been measured using the Ca test. PLED lifetimes of over 500 hours at 60 °C

  3. Beam test results of a 16 ps timing system based on ultra-fast silicon detectors

    Energy Technology Data Exchange (ETDEWEB)

    Cartiglia, N., E-mail: cartiglia@to.infn.it [INFN, Torino (Italy); Staiano, A.; Sola, V. [INFN, Torino (Italy); Arcidiacono, R. [INFN, Torino (Italy); Università del Piemonte Orientale (Italy); Cirio, R.; Cenna, F.; Ferrero, M.; Monaco, V.; Mulargia, R.; Obertino, M.; Ravera, F.; Sacchi, R. [INFN, Torino (Italy); Università di Torino, Torino (Italy); Bellora, A.; Durando, S. [Università di Torino, Torino (Italy); Mandurrino, M. [Politecnico di Torino, Torino (Italy); Minafra, N. [University of Kansas, KS (United States); Fadeyev, V.; Freeman, P.; Galloway, Z.; Gkougkousis, E. [SCIPP, University of California Santa Cruz, CA 95064 (United States); and others

    2017-04-01

    In this paper we report on the timing resolution obtained in a beam test with pions of 180 GeV/c momentum at CERN for the first production of 45 µm thick Ultra-Fast Silicon Detectors (UFSD). UFSD are based on the Low-Gain Avalanche Detector (LGAD) design, employing n-on-p silicon sensors with internal charge multiplication due to the presence of a thin, low-resistivity diffusion layer below the junction. The UFSD used in this test had a pad area of 1.7 mm{sup 2}. The gain was measured to vary between 5 and 70 depending on the sensor bias voltage. The experimental setup included three UFSD and a fast trigger consisting of a quartz bar readout by a SiPM. The timing resolution was determined by doing Gaussian fits to the time-of-flight of the particles between one or more UFSD and the trigger counter. For a single UFSD the resolution was measured to be 34 ps for a bias voltage of 200 V, and 27 ps for a bias voltage of 230 V. For the combination of 3 UFSD the timing resolution was 20 ps for a bias voltage of 200 V, and 16 ps for a bias voltage of 230 V.

  4. System tests with silicon strip module prototypes for the Phase-2-upgrade of the CMS tracker

    Energy Technology Data Exchange (ETDEWEB)

    Feld, Lutz; Karpinski, Waclaw; Klein, Katja; Preuten, Marius [I. Physikalisches Institut B, RWTH Aachen University (Germany)

    2016-07-01

    To prepare the CMS experiment for the High Luminosity LHC and its instantaneous luminosity of 5 . 10{sup 34} cm{sup -2}s{sup -1}, in the Long Shutdown 3 (around 2024) the CMS Silicon Tracker will be replaced. The Silicon Strip Modules for the new Tracker will host two vertically stacked sensors. The combination of hit information from both sensors will allow the estimation of the transverse momentum (p{sub T}) of charged particles in the module front-end. This can be used to identify hits from potential interesting high-p{sub T} tracks (above 2 GeV) for the first trigger level. The CMS Binary Chip (CBC) provides the analogue readout of two sensors and a digital section, into which the momentum discrimination is integrated. The modules will host a new DC-DC converter chain, which will allow individual powering of each module. First measurements with early prototypes on the interplay between DC-DC powering and the read-out functions of the module are presented in this talk.

  5. Enhanced Raman scattering in porous silicon grating.

    Science.gov (United States)

    Wang, Jiajia; Jia, Zhenhong; Lv, Changwu

    2018-03-19

    The enhancement of Raman signal on monocrystalline silicon gratings with varying groove depths and on porous silicon grating were studied for a highly sensitive surface enhanced Raman scattering (SERS) response. In the experiment conducted, porous silicon gratings were fabricated. Silver nanoparticles (Ag NPs) were then deposited on the porous silicon grating to enhance the Raman signal of the detective objects. Results show that the enhancement of Raman signal on silicon grating improved when groove depth increased. The enhanced performance of Raman signal on porous silicon grating was also further improved. The Rhodamine SERS response based on Ag NPs/ porous silicon grating substrates was enhanced relative to the SERS response on Ag NPs/ porous silicon substrates. Ag NPs / porous silicon grating SERS substrate system achieved a highly sensitive SERS response due to the coupling of various Raman enhancement factors.

  6. Perspective of metal encapsulation of waste

    International Nuclear Information System (INIS)

    Jardine, L.J.; Steindler, M.J.

    1978-01-01

    A conceptual flow sheet is presented for encapsulating solid, stabilized calcine (e.g., supercalcine) in a solid lead alloy, using existing or developing technologies. Unresolved and potential problem areas of the flow sheet are outlined and suggestions are made as how metal encapsulation might be applied to other solid wastes from the fuel cycle. It is concluded that metal encapsulation is a technique applicable to many forms of solid wastes and is likely to meet future waste isolation criteria and regulations

  7. 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.

  8. "Thunderstruck": Plasma-Polymer-Coated Porous Silicon Microparticles As a Controlled Drug Delivery System.

    Science.gov (United States)

    McInnes, Steven J P; Michl, Thomas D; Delalat, Bahman; Al-Bataineh, Sameer A; Coad, Bryan R; Vasilev, Krasimir; Griesser, Hans J; Voelcker, Nicolas H

    2016-02-01

    Controlling the release kinetics from a drug carrier is crucial to maintain a drug's therapeutic window. We report the use of biodegradable porous silicon microparticles (pSi MPs) loaded with the anticancer drug camphothecin, followed by a plasma polymer overcoating using a loudspeaker plasma reactor. Homogenous "Teflon-like" coatings were achieved by tumbling the particles by playing AC/DC's song "Thunderstruck". The overcoating resulted in a markedly slower release of the cytotoxic drug, and this effect correlated positively with the plasma polymer coating times, ranging from 2-fold up to more than 100-fold. Ultimately, upon characterizing and verifying pSi MP production, loading, and coating with analytical methods such as time-of-flight secondary ion mass spectrometry, scanning electron microscopy, thermal gravimetry, water contact angle measurements, and fluorescence microscopy, human neuroblastoma cells were challenged with pSi MPs in an in vitro assay, revealing a significant time delay in cell death onset.

  9. Characterization of a bonding-in-liquid technique for liquid encapsulation into MEMS devices

    International Nuclear Information System (INIS)

    Okayama, Yoshiyuki; Nakahara, Keijiro; Arouette, Xavier; Ninomiya, Takeshi; Matsumoto, Yasuaki; Orimo, Yoshinori; Hotta, Atsushi; Omiya, Masaki; Miki, Norihisa

    2010-01-01

    We demonstrate and characterize a new bonding-in-liquid technique (BiLT) for the encapsulation of liquids in MEMS devices. Liquid encapsulation enables innovative MEMS devices with various functions exploiting the unique characteristics of liquids, such as high deformation and spherical shape due to surface tension. Interfusion of air bubbles, variation of the liquid quantity and leakage of the encapsulated liquid must be avoided, or device performance will deteriorate. In BiLT, two structural layers are passively aligned and brought into contact in a solution, and the encapsulation cavities are filled uniformly with liquid, without air bubbles. A UV-curable resin is used as an adhesive that does not require heat or vacuum to bond the layers, but UV irradiation. DI water, glycerin and phosphate buffer saline were successfully encapsulated in silicon structural layers with PDMS membranes. We experimentally evaluated the bond strengths and alignment accuracy of BiLT in order to provide crucial information for the application of this process to the packaging and/or manufacturing of MEMS devices. Since conventional aligners are not applicable to BiLT, we experimentally evaluated the accuracy of an in-solution passive alignment process, which made use of matching concave and convex structures.

  10. Flowmeter with silicon flow tube

    NARCIS (Netherlands)

    Lammerink, Theodorus S.J.; Dijkstra, Marcel; Haneveld, J.; Lötters, Joost Conrad

    2009-01-01

    A flowmeter comprising a system chip with a silicon substrate provided on a carrier, in an opening whereof at least one silicon flow tube is provided for transporting a medium whose flow rate is to be measured, said tube having two ends that issue via a wall of the opening into channels coated with

  11. Research and development of photovoltaic power system. Study on structural defects in silicon-based amorphous materials; Taiyoko hatsuden system no kenkyu kaihatsu. Amorphous silicon kei zairyo no kozo kekkan ni kansuru kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    Shimizu, T [Kanazawa University, Ishikawa (Japan). Faculty of Engineering

    1994-12-01

    Described herein are the results of the FY1994 research program for structural defects of silicon-based amorphous materials for solar cells. The study on light generation defects of the a-Si:H system and rejuvenation process by annealing establishes the effects of light irradiation time on changed neutral dangling bond density as a result of light irradiation at varying temperature of 77K, room temperature and 393K. The study on annealing to rejuvenate light generation defects of various types of a-Si-H systems establishes the activation energy distribution with respect to annealing to remove light-induced defects, showing that hydrogen affects the distribution of light-induced defects. The study on decaying process of light-induced ESR for undoped and N-doped a-Si:H systems observes the decaying process of light-induced ESR, after light is cut off, extending for a period of several seconds to several hours at 77K for the a-Si-H systems containing N in a range from 0 to 12at%. The other results presented are space distribution of neutral defects of light-irradiated a-Si-H systems, and rejuvenation process of light-induced spin for the a-Si(1-x)N(x):H composition. 6 figs.

  12. Studies of a Next-Generation Silicon-Photomultiplier-Based Time-of-Flight PET/CT System.

    Science.gov (United States)

    Hsu, David F C; Ilan, Ezgi; Peterson, William T; Uribe, Jorge; Lubberink, Mark; Levin, Craig S

    2017-09-01

    This article presents system performance studies for the Discovery MI PET/CT system, a new time-of-flight system based on silicon photomultipliers. System performance and clinical imaging were compared between this next-generation system and other commercially available PET/CT and PET/MR systems, as well as between different reconstruction algorithms. Methods: Spatial resolution, sensitivity, noise-equivalent counting rate, scatter fraction, counting rate accuracy, and image quality were characterized with the National Electrical Manufacturers Association NU-2 2012 standards. Energy resolution and coincidence time resolution were measured. Tests were conducted independently on two Discovery MI scanners installed at Stanford University and Uppsala University, and the results were averaged. Back-to-back patient scans were also performed between the Discovery MI, Discovery 690 PET/CT, and SIGNA PET/MR systems. Clinical images were reconstructed using both ordered-subset expectation maximization and Q.Clear (block-sequential regularized expectation maximization with point-spread function modeling) and were examined qualitatively. Results: The averaged full widths at half maximum (FWHMs) of the radial/tangential/axial spatial resolution reconstructed with filtered backprojection at 1, 10, and 20 cm from the system center were, respectively, 4.10/4.19/4.48 mm, 5.47/4.49/6.01 mm, and 7.53/4.90/6.10 mm. The averaged sensitivity was 13.7 cps/kBq at the center of the field of view. The averaged peak noise-equivalent counting rate was 193.4 kcps at 21.9 kBq/mL, with a scatter fraction of 40.6%. The averaged contrast recovery coefficients for the image-quality phantom were 53.7, 64.0, 73.1, 82.7, 86.8, and 90.7 for the 10-, 13-, 17-, 22-, 28-, and 37-mm-diameter spheres, respectively. The average photopeak energy resolution was 9.40% FWHM, and the average coincidence time resolution was 375.4 ps FWHM. Clinical image comparisons between the PET/CT systems demonstrated the high

  13. Note: A silicon-on-insulator microelectromechanical systems probe scanner for on-chip atomic force microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Fowler, Anthony G.; Maroufi, Mohammad; Moheimani, S. O. Reza, E-mail: Reza.Moheimani@newcastle.edu.au [School of Electrical Engineering and Computer Science, University of Newcastle, Callaghan, NSW 2308 (Australia)

    2015-04-15

    A new microelectromechanical systems-based 2-degree-of-freedom (DoF) scanner with an integrated cantilever for on-chip atomic force microscopy (AFM) is presented. The silicon cantilever features a layer of piezoelectric material to facilitate its use for tapping mode AFM and enable simultaneous deflection sensing. Electrostatic actuators and electrothermal sensors are used to accurately position the cantilever within the x-y plane. Experimental testing shows that the cantilever is able to be scanned over a 10 μm × 10 μm window and that the cantilever achieves a peak-to-peak deflection greater than 400 nm when excited at its resonance frequency of approximately 62 kHz.

  14. Experimental investigation of silicon photomultipliers as compact light readout systems for gamma-ray spectroscopy applications in fusion plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Nocente, M., E-mail: massimo.nocente@mib.infn.it; Gorini, G. [Dipartimento di Fisica “G. Occhialini,” Università degli Studi di Milano-Bicocca, Milano (Italy); Istituto di Fisica del Plasma “P. Caldirola,” EURATOM-ENEA-CNR Association, Milano (Italy); Fazzi, A.; Lorenzoli, M.; Pirovano, C. [Dipartimento di Energia, CeSNEF, Politecnico di Milano, Milano (Italy); Istituto Nazionale di Fisica Nucleare, Sezione di Milano, Milano (Italy); Tardocchi, M. [Istituto di Fisica del Plasma “P. Caldirola,” EURATOM-ENEA-CNR Association, Milano (Italy); Cazzaniga, C.; Rebai, M. [Dipartimento di Fisica “G. Occhialini,” Università degli Studi di Milano-Bicocca, Milano (Italy); Uboldi, C.; Varoli, V. [Dipartimento di Energia, CeSNEF, Politecnico di Milano, Milano (Italy)

    2014-11-15

    A matrix of Silicon Photo Multipliers has been developed for light readout from a large area 1 in. × 1 in. LaBr{sub 3} crystal. The system has been characterized in the laboratory and its performance compared to that of a conventional photo multiplier tube. A pulse duration of 100 ns was achieved, which opens up to spectroscopy applications at high counting rates. The energy resolution measured using radioactive sources extrapolates to 3%–4% in the energy range E{sub γ} = 3–5 MeV, enabling gamma-ray spectroscopy measurements at good energy resolution. The results reported here are of relevance in view of the development of compact gamma-ray detectors with spectroscopy capabilities, such as an enhanced gamma-ray camera for high power fusion plasmas, where the use of photomultiplier is impeded by space limitation and sensitivity to magnetic fields.

  15. Silicon concentrator cells in a two-stage photovoltaic system with a concentration factor of 300x

    Energy Technology Data Exchange (ETDEWEB)

    Mohr, A.

    2005-06-15

    In this work a rear contacted silicon concentrator cell was developed for an application in a two stage concentrator photovoltaic system. This system was developed at Fraunhofer ISE some years ago. The innovation of this one-axis tracked system is that it enables a high geometrical concentration of 300x in combination with a high optical efficiency (around 78%) and a large acceptance angle of {+-}23.5 all year through. For this, the system uses a parabolic mirror (40.4x) and a three dimensional second stage consisting of compound parabolic concentrators (CPCs, 7.7x). For the concentrator concept and particularly for an easy cell integration, the rear line contacted concentrator (RLCC) cells with a maximum efficiency of 25% were developed and a hybrid mounting concept for the RLCC cells is presented. The optical performance of different CPC materials was tested and analysed in this work. Finally, small modules consisting of six series interconnected RLCC cells and six CPCs were integrated into the concentrator system and tested outdoor. A system efficiency of 16.2% was reached at around 800 W/m2 direct irradiance under realistic outdoor conditions. (orig.)

  16. Neuromorphic Silicon Neuron Circuits

    Science.gov (United States)

    Indiveri, Giacomo; Linares-Barranco, Bernabé; Hamilton, Tara Julia; van Schaik, André; Etienne-Cummings, Ralph; Delbruck, Tobi; Liu, Shih-Chii; Dudek, Piotr; Häfliger, Philipp; Renaud, Sylvie; Schemmel, Johannes; Cauwenberghs, Gert; Arthur, John; Hynna, Kai; Folowosele, Fopefolu; Saighi, Sylvain; Serrano-Gotarredona, Teresa; Wijekoon, Jayawan; Wang, Yingxue; Boahen, Kwabena

    2011-01-01

    Hardware implementations of spiking neurons can be extremely useful for a large variety of applications, ranging from high-speed modeling of large-scale neural systems to real-time behaving systems, to bidirectional brain–machine interfaces. The specific circuit solutions used to implement silicon neurons depend on the application requirements. In this paper we describe the most common building blocks and techniques used to implement these circuits, and present an overview of a wide range of neuromorphic silicon neurons, which implement different computational models, ranging from biophysically realistic and conductance-based Hodgkin–Huxley models to bi-dimensional generalized adaptive integrate and fire models. We compare the different design methodologies used for each silicon neuron design described, and demonstrate their features with experimental results, measured from a wide range of fabricated VLSI chips. PMID:21747754

  17. Neuromorphic silicon neuron circuits

    Directory of Open Access Journals (Sweden)

    Giacomo eIndiveri

    2011-05-01

    Full Text Available Hardware implementations of spiking neurons can be extremely useful for a large variety of applications, ranging from high-speed modeling of large-scale neural systems to real-time behaving systems, to bidirectional brain-machine interfaces. The specific circuit solutions used to implement silicon neurons depend on the application requirements. In this paper we describe the most common building blocks and techniques used to implement these circuits, and present an overview of a wide range of neuromorphic silicon neurons, which implement different computational models, ranging from biophysically realistic and conductance based Hodgkin-Huxley models to bi-dimensional generalized adaptive Integrate and Fire models. We compare the different design methodologies used for each silicon neuron design described, and demonstrate their features with experimental results, measured from a wide range of fabricated VLSI chips.

  18. Silicon-Based Nanoscale Composite Energetic Materials

    Science.gov (United States)

    2013-02-01

    1193-1211. 9. Krishnamohan, G., E.M. Kurian, and H.R. Rao, Thermal Analysis and Inverse Burning Rate Studies on Silicon-Potassium Nitrate System...reported in a journal paper and appears in the Appendix. Multiscale Nanoporous Silicon Combustion Introduction for nanoporous silicon effort While

  19. Porous silicon: X-rays sensitivity

    International Nuclear Information System (INIS)

    Gerstenmayer, J.L.; Vibert, Patrick; Mercier, Patrick; Rayer, Claude; Hyvernage, Michel; Herino, Roland; Bsiesy, Ahmad

    1994-01-01

    We demonstrate that high porosity anodically porous silicon is radioluminescent. Interests of this study are double. Firstly: is the construction of porous silicon X-rays detectors (imagers) possible? Secondly: is it necessary to protect silicon porous based optoelectronic systems from ionising radiations effects (spatial environment)? ((orig.))

  20. Breast imaging using an amorphous silicon-based full-field digital mammographic system: stability of a clinical prototype.

    Science.gov (United States)

    Vedantham, S; Karellas, A; Suryanarayanan, S; D'Orsi, C J; Hendrick, R E

    2000-11-01

    An amorphous silicon-based full-breast imager for digital mammography was evaluated for detector stability over a period of 1 year. This imager uses a structured CsI:TI scintillator coupled to an amorphous silicon layer with a 100-micron pixel pitch and read out by special purpose electronics. The stability of the system was characterized using the following quantifiable metrics: conversion factor (mean number of electrons generated per incident x-ray), presampling modulation transfer function (MTF), detector linearity and sensitivity, detector signal-to-noise ratio (SNR), and American College of Radiology (ACR) accreditation phantom scores. Qualitative metrics such as flat field uniformity, geometric distortion, and Society of Motion Picture and Television Engineers (SMPTE) test pattern image quality were also used to study the stability of the system. Observations made over this 1-year period indicated that the maximum variation from the average of the measurements were less than 0.5% for conversion factor, 3% for presampling MTF over all spatial frequencies, 5% for signal response, linearity and sensitivity, 12% for SNR over seven locations for all 3 target-filter combinations, and 0% for ACR accreditation phantom scores. ACR mammographic accreditation phantom images indicated the ability to resolve 5 fibers, 4 speck groups, and 5 masses at a mean glandular dose of 1.23 mGy. The SMPTE pattern image quality test for the display monitors used for image viewing indicated ability to discern all contrast steps and ability to distinguish line-pair images at the center and corners of the image. No bleeding effects were observed in the image. Flat field uniformity for all 3 target-filter combinations displayed no artifacts such as gridlines, bad detector rows or columns, horizontal or vertical streaks, or bad pixels. Wire mesh screen images indicated uniform resolution and no geometric distortion.

  1. Evaluation of silicon-chemiluminescence monitoring as a novel method for atomic fluorine determination and end point detection in plasma etch systems

    NARCIS (Netherlands)

    Zijlstra, P.A.; Beenakker, C.I.M.

    1981-01-01

    Optical methods for the detection of atomic fluorine in plasma etch systems are discussed and an experimental comparison is made between detection by optical emission and by a novel method based on the chemiluminescence from solid silicon in the presence of atomic fluorine. Although both methods

  2. Preliminary investigation of cryopreservation by encapsulation ...

    African Journals Online (AJOL)

    Protocorm-like bodies (PLBs) of Brassidium Shooting Star, a new commercial ornamental orchid hybrid, were cryopreserved by an encapsulation-dehydration technique. The effects of PLB size, various sucrose concentrations in preculture media and sodium alginate concentration for encapsulation were the main ...

  3. Designing a concentrating photovoltaic (CPV) system in adjunct with a silicon photovoltaic panel for a solar competition car

    Science.gov (United States)

    Arias-Rosales, Andrés.; Barrera-Velásquez, Jorge; Osorio-Gómez, Gilberto; Mejía-Gutiérrez, Ricardo

    2014-06-01

    Solar competition cars are a very interesting research laboratory for the development of new technologies heading to their further implementation in either commercial passenger vehicles or related applications. Besides, worldwide competitions allow the spreading of such ideas where the best and experienced teams bet on innovation and leading edge technologies, in order to develop more efficient vehicles. In these vehicles, some aspects generally make the difference such as aerodynamics, shape, weight, wheels and the main solar panels. Therefore, seeking to innovate in a competitive advantage, the first Colombian solar vehicle "Primavera", competitor at the World Solar Challenge (WSC)-2013, has implemented the usage of a Concentrating Photovoltaic (CPV) system as a complementary solar energy module to the common silicon photovoltaic panel. By harvesting sunlight with concentrating optical devices, CPVs are capable of maximizing the allowable photovoltaic area. However, the entire CPV system weight must be less harmful than the benefit of the extra electric energy generated, which in adjunct with added manufacture and design complexity, has intervened in the fact that CPVs had never been implemented in a solar car in such a scale as the one described in this work. Design considerations, the system development process and implementation are presented in this document considering both the restrictions of the context and the interaction of the CPV system with the solar car setup. The measured data evidences the advantage of using this complementary system during the competition and the potential this technology has for further developments.

  4. Design and Fabrication of Piezoresistive Based Encapsulated Poly-Si Cantilevers for Bio/chemical Sensing

    Science.gov (United States)

    Krishna, N. P. Vamsi; Murthy, T. R. Srinivasa; Reddy, K. Jayaprakash; Sangeeth, K.; Hegde, G. M.

    Cantilever-based sensing is a growing research field not only within micro regime but also in nano technology. The technology offers a method for rapid, on-line and in-situ monitoring of specific bio/chemical substances by detecting the nanomechanical responses of a cantilever sensor. Cantilever with piezoresistive based detection scheme is more attractive because of its electronics compatibility. Majority of commercially available micromachined piezoresistive sensors are bulk micromachined devices and are fabricated using single crystal silicon wafers. As substrate properties are not important in surface micromachining, the expensive silicon wafers can be replaced by cheaper substrates, such as poly-silicon, glass or plastic. Here we have designed SU-8 based bio/chemical compatible micro electro mechanical device that includes an encapsulated polysilicon piezoresistor for bio/chemical sensing. In this paper we report the design, fabrication and analysis of the encapsulated poly-Si cantilevers. Design and theoretical analysis are carried out using Finite Element Analysis software. For fabrication of poly-silicon piezoresistive cantilevers we followed the surface micromachining process steps. Preliminary characterization of the cantilevers is presented.

  5. Alginate: A Versatile Biomaterial to Encapsulate Isolated Ovarian Follicles.

    Science.gov (United States)

    Vanacker, Julie; Amorim, Christiani A

    2017-07-01

    In vitro culture of ovarian follicles isolated or enclosed in ovarian tissue fragments and grafting of isolated ovarian follicles represent a potential alternative to restore fertility in cancer patients who cannot undergo cryopreservation of embryos or oocytes or transplantation of frozen-thawed ovarian tissue. In this regard, respecting the three-dimensional (3D) architecture of isolated follicles is crucial to maintaining their proper follicular physiology. To this end, alginate hydrogel has been widely investigated using follicles from numerous animal species, yielding promising results. The goal of this review is therefore to provide an overview of alginate applications utilizing the biomaterial as a scaffold for 3D encapsulation of isolated ovarian follicles. Different methods of isolated follicle encapsulation in alginate are discussed in this review, as its use of 3D alginate culture systems as a tool for in vitro follicle analysis. Possible improvements of this matrix, namely modification with arginine-glycine-aspartic acid peptide or combination with fibrin, are also summarized. Encouraging results have been obtained in different animal models, and particularly with isolated follicles encapsulated in alginate matrices and grafted to mice. This summary is designed to guide the reader towards development of next-generation alginate scaffolds, with enhanced properties for follicle encapsulation.

  6. Electrical activation of phosphorus in silicon

    International Nuclear Information System (INIS)

    Goh, K.E.J.; Oberbeck, L.; Simmons, M.Y.; Clark, R.G.

    2003-01-01

    Full text: We present studies of phosphorus δ-doping in silicon with a view to determining the degree of electrical activation of the dopants. These results have a direct consequence for the use of phosphorus as a qubit in a silicon-based quantum computer such as that proposed by Kane. Room temperature and 4 K Hall effect measurements are presented for phosphorus δ-doped layers grown in n-type silicon using two different methods. In the first method, the δ-layer was deposited by a phosphorus effusion cell in an MBE chamber. In the second method, the Si surface was dosed with phosphine gas and then annealed to 550 deg C to incorporate P into the substrate. In both methods, the P δ-doped layer was subsequently encapsulated by ∼25 nm of Si grown epitaxially. We discuss the implications of our results on the fabrication of the Kane quantum computer

  7. Full-color OLED on silicon microdisplay

    Science.gov (United States)

    Ghosh, Amalkumar P.

    2002-02-01

    eMagin has developed numerous enhancements to organic light emitting diode (OLED) technology, including a unique, up- emitting structure for OLED-on-silicon microdisplay devices. Recently, eMagin has fabricated full color SVGA+ resolution OLED microdisplays on silicon, with over 1.5 million color elements. The display is based on white light emission from OLED followed by LCD-type red, green and blue color filters. The color filters are patterned directly on OLED devices following suitable thin film encapsulation and the drive circuits are built directly on single crystal silicon. The resultant color OLED technology, with hits high efficiency, high brightness, and low power consumption, is ideally suited for near to the eye applications such as wearable PCS, wireless Internet applications and mobile phone, portable DVD viewers, digital cameras and other emerging applications.

  8. Effect of drug loading method against drug dissolution mechanism of encapsulated amoxicillin trihydrate in matrix of semi-IPN chitosan-poly(N-vinylpyrrolidone) hydrogel with KHCO3 as pore forming agent in floating drug delivery system

    Science.gov (United States)

    Fimantari, Khansa; Budianto, Emil

    2018-04-01

    Helicobacterpylori infection can be treated using trihydrate amoxicillin. However, this treatment is not effective enough, as the conventional dosage treatment has a relatively short retention time in the human stomach. In the present study, the amoxicillin trihydrate drug will be encapsulated into a semi-IPN K-PNVP hydrogel matrix with 7,5% KHCO3 as a pore-forming agent. The encapsulated drug is tested with in vitro method to see the efficiency of its encapsulation and dissolution. The hydrogel in situ loading produces an encapsulation efficiency value. The values of the encapsulation efficiency are 95% and 98%, while post loading hydrogel yields an encapsulation efficiency value is 77% and the dissolution is 84%. The study of drug dissolution mechanism was done by using mathematical equation model to know its kinetics and its mechanism of dissolution. The post loading hydrogel was done by using thefirst-order model, while hydrogel in situ loading used Higuchi model. The Korsmeyer-Peppas model shows that post loading hydrogel dissolution mechanism is a mixture of diffusion and erosion, and in situ loading hydrogel in the form of diffusion. It is supported by the results of hydrogel characterization, before and after dissolution test with an optical microscope. The results of the optical microscope show that the hydrogel surface before and after the dissolution tested for both methods shows the change becomes rougher.

  9. Treatment of diabetic rats with encapsulated islets.

    Science.gov (United States)

    Sweet, Ian R; Yanay, Ofer; Waldron, Lanaya; Gilbert, Merle; Fuller, Jessica M; Tupling, Terry; Lernmark, Ake; Osborne, William R A

    2008-12-01

    Immunoprotection of islets using bioisolator systems permits introduction of allogeneic cells to diabetic patients without the need for immunosuppression. Using TheraCyte immunoisolation devices, we investigated two rat models of type 1 diabetes mellitus (T1DM), BB rats and rats made diabetic by streptozotocin (STZ) treatment. We chose to implant islets after the onset of diabetes to mimic the probable treatment of children with T1DM as they are usually diagnosed after disease onset. We encapsulated 1000 rat islets and implanted them subcutaneously (SQ) into diabetic biobreeding (BB) rats and STZ-induced diabetic rats, defined as two or more consecutive days of blood glucose>350 mg/dl. Rats were monitored for weight and blood glucose. Untreated BB rats rapidly lost weight and were euthanized at >20% weight loss that occurred between 4 and 10 days from implantation. For period of 30-40 days following islet implantation weights of treated rats remained steady or increased. Rapid weight loss occurred after surgical removal of devices that contained insulin positive islets. STZ-treated rats that received encapsulated islets showed steady weight gain for up to 130 days, whereas untreated control rats showed steady weight loss that achieved >20% at around 55 days. Although islet implants did not normalize blood glucose, treated rats were apparently healthy and groomed normally. Autologous or allogeneic islets were equally effective in providing treatment. TheraCyte devices can sustain islets, protect allogeneic cells from immune attack and provide treatment for diabetic-mediated weight loss in both BB rats and STZ-induced diabetic rats.

  10. Transparent amorphous silicon sensors for the alignment system of particle detectors

    International Nuclear Information System (INIS)

    Fernandez, M.G.

    1999-01-01

    In this document we will present a historical review of ALMY sensors. The starting point was 1993 when the first prototypes were built. A description of their performance at this early stage will make clear which features have to be modified in order to cope with the stringent requirements imposed by ATLAS and CMS. As time went by, the problems were fixed and nowadays a fine working and operational ALMY sensor has been built. The following sections of this paper show how these aims were achieved. In section 2 the reader will know where and when ALMY sensors were born. It explains some reasons why amorphous silicon was chosen as photosensitive material. Section 3 intends to describe the morphology and physical properties of this device. Next sections present results from the diverse characterizations from ATLAS and CMS. Particularly, section 4 deals with the uniformity and spatial resolution of the first prototypes. Details on the light transmission after one sensor are given in section 5. The different radiation hardness tests for ALMYs are introduced in section 6. The propagation of a plane wave through the different layers helps to understand the origin of the systematics found in the first prototypes (section 7). The performance of the new ALMY sensors is presented in section 8. (author)

  11. Transparent amorphous silicon sensors for the alignment system of particle detectors

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez, M.G. [Ciemat, Madrid (Spain)

    1999-07-01

    In this document we will present a historical review of ALMY sensors. The starting point was 1993 when the first prototypes were built. A description of their performance at this early stage will make clear which features have to be modified in order to cope with the stringent requirements imposed by ATLAS and CMS. As time went by, the problems were fixed and nowadays a fine working and operational ALMY sensor has been built. The following sections of this paper show how these aims were achieved. In section 2 the reader will know where and when ALMY sensors were born. It explains some reasons why amorphous silicon was chosen as photosensitive material. Section 3 intends to describe the morphology and physical properties of this device. Next sections present results from the diverse characterizations from ATLAS and CMS. Particularly, section 4 deals with the uniformity and spatial resolution of the first prototypes. Details on the light transmission after one sensor are given in section 5. The different radiation hardness tests for ALMYs are introduced in section 6. The propagation of a plane wave through the different layers helps to understand the origin of the systematics found in the first prototypes (section 7). The performance of the new ALMY sensors is presented in section 8. (author)

  12. Joining and Integration of Silicon Nitride Ceramics for Aerospace and Energy Systems

    Science.gov (United States)

    Singh, M.; Asthana, R.

    2009-01-01

    Light-weight, creep-resistant silicon nitride ceramics possess excellent high-temperature strength and are projected to significantly raise engine efficiency and performance when used as turbine components in the next-generation turbo-shaft engines without the extensive cooling that is needed for metallic parts. One key aspect of Si3N4 utilization in such applications is its joining response to diverse materials. In an ongoing research program, the joining and integration of Si3N4 ceramics with metallic, ceramic, and composite materials using braze interlayers with the liquidus temperature in the range 750-1240C is being explored. In this paper, the self-joining behavior of Kyocera Si3N4 and St. Gobain Si3N4 using a ductile Cu-based active braze (Cu-ABA) containing Ti will be presented. Joint microstructure, composition, hardness, and strength as revealed by optical microscopy, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), Knoop microhardness test, and offset compression shear test will be presented. Additionally, microstructure, composition, and joint strength of Si3N4/Inconel 625 joints made using Cu-ABA, will be presented. The results will be discussed with reference to the role of chemical reactions, wetting behavior, and residual stresses in joints.

  13. The rad-hard readout system of the BaBar silicon vertex tracker

    Science.gov (United States)

    Re, V.; DeWitt, J.; Dow, S.; Frey, A.; Johnson, R. P.; Kroeger, W.; Kipnis, I.; Leona, A.; Luo, L.; Mandelli, E.; Manfredi, P. F.; Nyman, M.; Pedrali-Noy, M.; Poplevin, P.; Perazzo, A.; Roe, N.; Spencer, N.

    1998-02-01

    This paper discusses the behaviour of a prototype rad-hard version of the chip developed for the readout of the BaBar silicon vertex tracker. A previous version of the chip, implemented in the 0.8 μm HP rad-soft version has been thoroughly tested in the recent times. It featured outstanding noise characteristics and showed that the specifications assumed as target for the tracker readout were met to a very good extent. The next step was the realization of a chip prototype in the rad-hard process that will be employed in the actual chip production. Such a prototype is structurally and functionally identical to its rad-soft predecessor. However, the process parameters being different, and not fully mastered at the time of design, some deviations in the behaviour were to be expected. The reasons for such deviations have been identified and some of them were removed by acting on the points that were left accessible on the chip. Other required small circuit modifications that will not affect the production schedule. The tests done so far on the rad-hard chip have shown that the noise behaviour is very close to that of the rad-soft version, that is fully adequate for the vertex detector readout.

  14. Liposome Encapsulation of Vitamins to Enhance Storage Properties of Space-Bound Food, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — InnoSense LLC (ISL) proposes to develop a nanoparticle encapsulation systems for water- and fat-soluble vitamins (VitaCap™) to increase shelf life up to five years...

  15. Silicon Qubits

    Energy Technology Data Exchange (ETDEWEB)

    Ladd, Thaddeus D. [HRL Laboratories, LLC, Malibu, CA (United States); Carroll, Malcolm S. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2018-02-28

    Silicon is a promising material candidate for qubits due to the combination of worldwide infrastructure in silicon microelectronics fabrication and the capability to drastically reduce decohering noise channels via chemical purification and isotopic enhancement. However, a variety of challenges in fabrication, control, and measurement leaves unclear the best strategy for fully realizing this material’s future potential. In this article, we survey three basic qubit types: those based on substitutional donors, on metal-oxide-semiconductor (MOS) structures, and on Si/SiGe heterostructures. We also discuss the multiple schema used to define and control Si qubits, which may exploit the manipulation and detection of a single electron charge, the state of a single electron spin, or the collective states of multiple spins. Far from being comprehensive, this article provides a brief orientation to the rapidly evolving field of silicon qubit technology and is intended as an approachable entry point for a researcher new to this field.

  16. ALICE Silicon Pixel Detector

    CERN Multimedia

    Manzari, V

    2013-01-01

    The Silicon Pixel Detector (SPD) forms the innermost two layers of the 6-layer barrel Inner Tracking System (ITS). The SPD plays a key role in the determination of the position of the primary collision and in the reconstruction of the secondary vertices from particle decays.

  17. ALICE Silicon Strip Detector

    CERN Multimedia

    Nooren, G

    2013-01-01

    The Silicon Strip Detector (SSD) constitutes the two outermost layers of the Inner Tracking System (ITS) of the ALICE Experiment. The SSD plays a crucial role in the tracking of the particles produced in the collisions connecting the tracks from the external detectors (Time Projection Chamber) to the ITS. The SSD also contributes to the particle identification through the measurement of their energy loss.

  18. Electrical leakage phenomenon in heteroepitaxial cubic silicon carbide on silicon

    Science.gov (United States)

    Pradeepkumar, Aiswarya; Zielinski, Marcin; Bosi, Matteo; Verzellesi, Giovanni; Gaskill, D. Kurt; Iacopi, Francesca

    2018-06-01

    Heteroepitaxial 3C-SiC films on silicon substrates are of technological interest as enablers to integrate the excellent electrical, electronic, mechanical, thermal, and epitaxial properties of bulk silicon carbide into well-established silicon technologies. One critical bottleneck of this integration is the establishment of a stable and reliable electronic junction at the heteroepitaxial interface of the n-type SiC with the silicon substrate. We have thus investigated in detail the electrical and transport properties of heteroepitaxial cubic silicon carbide films grown via different methods on low-doped and high-resistivity silicon substrates by using van der Pauw Hall and transfer length measurements as test vehicles. We have found that Si and C intermixing upon or after growth, particularly by the diffusion of carbon into the silicon matrix, creates extensive interstitial carbon traps and hampers the formation of a stable rectifying or insulating junction at the SiC/Si interface. Although a reliable p-n junction may not be realistic in the SiC/Si system, we can achieve, from a point of view of the electrical isolation of in-plane SiC structures, leakage suppression through the substrate by using a high-resistivity silicon substrate coupled with deep recess etching in between the SiC structures.

  19. A new large solid angle multi-element silicon drift detector system for low energy X-ray fluorescence spectroscopy

    Science.gov (United States)

    Bufon, J.; Schillani, S.; Altissimo, M.; Bellutti, P.; Bertuccio, G.; Billè, F.; Borghes, R.; Borghi, G.; Cautero, G.; Cirrincione, D.; Fabiani, S.; Ficorella, F.; Gandola, M.; Gianoncelli, A.; Giuressi, D.; Kourousias, G.; Mele, F.; Menk, R. H.; Picciotto, A.; Rachevski, A.; Rashevskaya, I.; Sammartini, M.; Stolfa, A.; Zampa, G.; Zampa, N.; Zorzi, N.; Vacchi, A.

    2018-03-01

    Low-energy X-ray fluorescence (LEXRF) is an essential tool for bio-related research of organic samples, whose composition is dominated by light elements. Working at energies below 2 keV and being able to detect fluorescence photons of lightweight elements such as carbon (277 eV) is still a challenge, since it requires in-vacuum operations to avoid in-air photon absorption. Moreover, the detectors must have a thin entrance window and collect photons at an angle of incidence near 90 degrees to minimize the absorption by the protective coating. Considering the low fluorescence yield of light elements, it is important to cover a substantial part of the solid angle detecting ideally all emitted X-ray fluorescence (XRF) photons. Furthermore, the energy resolution of the detection system should be close to the Fano limit in order to discriminate elements whose XRF emission lines are often very close within the energy spectra. To ensure all these features, a system consisting of four monolithic multi-element silicon drift detectors was developed. The use of four separate detector units allows optimizing the incidence angle on all the sensor elements. The multi-element approach in turn provides a lower leakage current on each anode, which, in combination with ultra-low noise preamplifiers, is necessary to achieve an energy resolution close to the Fano limit. The potential of the new detection system and its applicability for typical LEXRF applications has been proved on the Elettra TwinMic beamline.

  20. Digital chest radiography with an amorphous silicon flat-panel-detector versus a storage-phosphor system: comparison of soft-copy images

    International Nuclear Information System (INIS)

    Lee, Hyun Ju; Im, Jung Gi; Goo, Jin Mo; Lee, Chang Hyun

    2006-01-01

    We compared the soft-copy images produced by an amorphous silicon flat-panel-detector system with the images produced by a storage-phosphor radiography system for their ability to visualize anatomic regions of the chest. Two chest radiologists independently analyzed 234 posteroanterior chest radiographs obtained from 78 patients on high-resolution liquid crystal display monitors (2560 x 2048 x 8 bits). In each patient, one radiograph was obtained with a storage-phosphor system, and two radiographs were obtained via amorphous silicon flat-panel-detector radiography with and without spatial frequency filtering. After randomizing the 234 images, the interpreters rated the visibility and radiographic quality of 11 different anatomic regions. Each image was ranked on a five-point scale (1 = not visualized, 2 = poor visualization, 3 = fair visualization, 4 = good visualization, and 5 = excellent visualization). The statistical difference between each system was determined using the Wilcoxon's signed rank test. The visibility of three anatomic regions (hilum, heart border and ribs), as determined by the chest radiologist with 14 years experience (ρ < 0.05) and the visibility of the thoracic spine, as determined by the chest radiologist with 8 years experience (ρ = 0.036), on the amorphous silicon flat-panel-detector radiography prior to spatial frequency filtering were significantly superior to that on the storage-phosphor radiography. The visibility of 11 anatomic regions, as determined by the chest radiologist with 14 years experience (ρ < 0.0001) and the visibility of five anatomic regions (unobscured lung, rib, proximal airway, thoracic spine and overall appearance), as determined by the chest radiologist with 8 years experience (ρ < 0.05), on the amorphous silicon flat-panel-detector radiography after spatial frequency filtering were significantly superior to that on the storage-phosphor radiography. The amorphous silicon flat-panel-detector system depicted the

  1. Full-scale demonstration. Fire testing of a system for penetration sealing based on foamed silicone elastomer: Studsvik 77-05-26

    International Nuclear Information System (INIS)

    Brown, A.

    1978-06-01

    Testing of a system for making fire retardant penetration seals based on foamed-in-place silicone elastomer is described. The report covers - Concept of fire retardant penetration seals and the Chemtrol system, Design FC 225 - Account of materials used to prepare seals and method of application - Test assembly and full-scale facility at Studsvik - Classification of seals used in demonstration - Diagrams of seals and photographs taken after demonstration

  2. Full-scale demonstration. Fire testing of a system for penetration sealing based on foamed silicone elastomer: Studsvik 77-05-26

    International Nuclear Information System (INIS)

    Brown, A.

    1978-06-01

    Testing of a system for making fire retardant penetration seals based on foamed-in-place silicone elastomer is described. The report covers - Concept of fire retardant penetration seals and the Chemtrol system, Design FC 225 - Account of materials used to prepare seals and method of application - Test assembly and full-scale facility at Studsvik - Classification of seals used in demonstration - Diagrams of seals and photographs taken after demonstration (author)

  3. The encapsulation of Magnox type fuel elements for extended storage in cooling ponds

    International Nuclear Information System (INIS)

    Baker, D.W.C.; Burt, G.A.

    1978-01-01

    A method of encapsulating spent fuel elements in a protective plastics medium to enable them to be stored for protracted periods under water, without risk of further significant corrosion, has been developed. It is visualised that the elements after discharge from the reactor would be allowed to cool under water for a period of at least 100 days and would then be encapsulated while remaining immersed. A suitable two pack system based on a solvent free epoxy resin cured with an aromatic amine adduct has been identified. The equipment and processes which have been developed for handling, conditioning and encapsulating the fuel are described. (author)

  4. Secure encapsulation and publication of biological services in the cloud computing environment.

    Science.gov (United States)

    Zhang, Weizhe; Wang, Xuehui; Lu, Bo; Kim, Tai-hoon

    2013-01-01

    Secure encapsulation and publication for bioinformatics software products based on web service are presented, and the basic function of biological information is realized in the cloud computing environment. In the encapsulation phase, the workflow and function of bioinformatics software are conducted, the encapsulation interfaces are designed, and the runtime interaction between users and computers is simulated. In the publication phase, the execution and management mechanisms and principles of the GRAM components are analyzed. The functions such as remote user job submission and job status query are implemented by using the GRAM components. The services of bioinformatics software are published to remote users. Finally the basic prototype system of the biological cloud is achieved.

  5. Use of integrin-linked kinase to extend function of encapsulated pancreatic tissue

    International Nuclear Information System (INIS)

    Blanchette, James O; Langer, Steven J; Leinwand, Leslie L; Sahai, Suchit; Topiwala, Pritesh S; Anseth, Kristi S

    2010-01-01

    We have studied the impact of overexpression of an intracellular signaling protein, integrin-linked kinase (ILK), on the survival and function of encapsulated islet tissue used for the treatment of type 1 diabetes. The dimensions of the encapsulated tissue can impact the stresses placed on the tissue and ILK overexpression shows the ability to extend function of dissociated cells as well as intact islets. These results suggest that lost cell-extracellular matrix interactions in cell encapsulation systems can lead to decreased insulin secretion and ILK signaling is a target to overcome this phenomenon. (communication)

  6. Use of integrin-linked kinase to extend function of encapsulated pancreatic tissue

    Energy Technology Data Exchange (ETDEWEB)

    Blanchette, James O [Department of Chemical Engineering, University of South Carolina, Columbia, SC (United States); Langer, Steven J; Leinwand, Leslie L [Department of Molecular, Cellular and Developmental Biology, University of Colorado, Boulder, CO (United States); Sahai, Suchit; Topiwala, Pritesh S [Biomedical Engineering Program, University of South Carolina, Columbia, SC (United States); Anseth, Kristi S, E-mail: blanchej@cec.sc.ed [Howard Hughes Medical Institute, Boulder, CO (United States)

    2010-12-15

    We have studied the impact of overexpression of an intracellular signaling protein, integrin-linked kinase (ILK), on the survival and function of encapsulated islet tissue used for the treatment of type 1 diabetes. The dimensions of the encapsulated tissue can impact the stresses placed on the tissue and ILK overexpression shows the ability to extend function of dissociated cells as well as intact islets. These results suggest that lost cell-extracellular matrix interactions in cell encapsulation systems can lead to decreased insulin secretion and ILK signaling is a target to overcome this phenomenon. (communication)

  7. Microstructure factor and mechanical and electronic properties of hydrogenated amorphous and nanocrystalline silicon thin-films for microelectromechanical systems applications

    International Nuclear Information System (INIS)

    Mouro, J.; Gualdino, A.; Chu, V.; Conde, J. P.

    2013-01-01

    Thin-film silicon allows the fabrication of MEMS devices at low processing temperatures, compatible with monolithic integration in advanced electronic circuits, on large-area, low-cost, and flexible substrates. The most relevant thin-film properties for applications as MEMS structural layers are the deposition rate, electrical conductivity, and mechanical stress. In this work, n + -type doped hydrogenated amorphous and nanocrystalline silicon thin-films were deposited by RF-PECVD, and the influence of the hydrogen dilution in the reactive mixture, the RF-power coupled to the plasma, the substrate temperature, and the deposition pressure on the structural, electrical, and mechanical properties of the films was studied. Three different types of silicon films were identified, corresponding to three internal structures: (i) porous amorphous silicon, deposited at high rates and presenting tensile mechanical stress and low electrical conductivity, (ii) dense amorphous silicon, deposited at intermediate rates and presenting compressive mechanical stress and higher values of electrical conductivity, and (iii) nanocrystalline silicon, deposited at very low rates and presenting the highest compressive mechanical stress and electrical conductivity. These results show the combinations of electromechanical material properties available in silicon thin-films and thus allow the optimized selection of a thin silicon film for a given MEMS application. Four representative silicon thin-films were chosen to be used as structural material of electrostatically actuated MEMS microresonators fabricated by surface micromachining. The effect of the mechanical stress of the structural layer was observed to have a great impact on the device resonance frequency, quality factor, and actuation force

  8. Microstructure factor and mechanical and electronic properties of hydrogenated amorphous and nanocrystalline silicon thin-films for microelectromechanical systems applications

    Energy Technology Data Exchange (ETDEWEB)

    Mouro, J.; Gualdino, A.; Chu, V. [Instituto de Engenharia de Sistemas e Computadores – Microsistemas e Nanotecnologias (INESC-MN) and IN – Institute of Nanoscience and Nanotechnology, 1000-029 Lisbon (Portugal); Conde, J. P. [Instituto de Engenharia de Sistemas e Computadores – Microsistemas e Nanotecnologias (INESC-MN) and IN – Institute of Nanoscience and Nanotechnology, 1000-029 Lisbon (Portugal); Department of Bioengineering, Instituto Superior Técnico (IST), 1049-001 Lisbon (Portugal)

    2013-11-14

    Thin-film silicon allows the fabrication of MEMS devices at low processing temperatures, compatible with monolithic integration in advanced electronic circuits, on large-area, low-cost, and flexible substrates. The most relevant thin-film properties for applications as MEMS structural layers are the deposition rate, electrical conductivity, and mechanical stress. In this work, n{sup +}-type doped hydrogenated amorphous and nanocrystalline silicon thin-films were deposited by RF-PECVD, and the influence of the hydrogen dilution in the reactive mixture, the RF-power coupled to the plasma, the substrate temperature, and the deposition pressure on the structural, electrical, and mechanical properties of the films was studied. Three different types of silicon films were identified, corresponding to three internal structures: (i) porous amorphous silicon, deposited at high rates and presenting tensile mechanical stress and low electrical conductivity, (ii) dense amorphous silicon, deposited at intermediate rates and presenting compressive mechanical stress and higher values of electrical conductivity, and (iii) nanocrystalline silicon, deposited at very low rates and presenting the highest compressive mechanical stress and electrical conductivity. These results show the combinations of electromechanical material properties available in silicon thin-films and thus allow the optimized selection of a thin silicon film for a given MEMS application. Four representative silicon thin-films were chosen to be used as structural material of electrostatically actuated MEMS microresonators fabricated by surface micromachining. The effect of the mechanical stress of the structural layer was observed to have a great impact on the device resonance frequency, quality factor, and actuation force.

  9. Production of electronic grade lunar silicon by disproportionation of silicon difluoride

    Science.gov (United States)

    Agosto, William N.

    1993-01-01

    Waldron has proposed to extract lunar silicon by sodium reduction of sodium fluorosilicate derived from reacting sodium fluoride with lunar silicon tetrafluoride. Silicon tetrafluoride is obtained by the action of hydrofluoric acid on lunar silicates. While these reactions are well understood, the resulting lunar silicon is not likely to meet electronic specifications of 5 nines purity. Dale and Margrave have shown that silicon difluoride can be obtained by the action of silicon tetrafluoride on elemental silicon at elevated temperatures (1100-1200 C) and low pressures (1-2 torr). The resulting silicon difluoride will then spontaneously disproportionate into hyperpure silicon and silicon tetrafluoride in vacuum at approximately 400 C. On its own merits, silicon difluoride polymerizes into a tough waxy solid in the temperature range from liquid nitrogen to about 100 C. It is the silicon analog of teflon. Silicon difluoride ignites in moist air but is stable under lunar surface conditions and may prove to be a valuable industrial material that is largely lunar derived for lunar surface applications. The most effective driver for lunar industrialization may be the prospects for industrial space solar power systems in orbit or on the moon that are built with lunar materials. Such systems would require large quantities of electronic grade silicon or compound semiconductors for photovoltaics and electronic controls. Since silicon is the most abundant semimetal in the silicate portion of any solar system rock (approximately 20 wt percent), lunar silicon production is bound to be an important process in such a solar power project. The lunar silicon extraction process is discussed.

  10. Polyethylene encapsulation full-scale technology demonstration. Final report

    International Nuclear Information System (INIS)

    Kalb, P.D.; Lageraaen, P.R.

    1994-10-01

    A full-scale integrated technology demonstration of a polyethylene encapsulation process, sponsored by the US Department of Energy (DOE) Office of Technology Development (OTD), was conducted at the Environmental ampersand Waste Technology Center at Brookhaven National Laboratory (BNL.) in September 1994. As part of the Polymer Solidification National Effort, polyethylene encapsulation has been developed and tested at BNL as an alternative solidification technology for improved, cost-effective treatment of low-level radioactive (LLW), hazardous and mixed wastes. A fully equipped production-scale system, capable of processing 900 kg/hr (2000 lb/hr), has been installed at BNL. The demonstration covered all facets of the integrated processing system including pre-treatment of aqueous wastes, precise feed metering, extrusion processing, on-line quality control monitoring, and process control

  11. Comparative studies on osmosis based encapsulation of sodium diclofenac in porcine and outdated human erythrocyte ghosts.

    Science.gov (United States)

    Bukara, Katarina; Drvenica, Ivana; Ilić, Vesna; Stančić, Ana; Mišić, Danijela; Vasić, Borislav; Gajić, Radoš; Vučetić, Dušan; Kiekens, Filip; Bugarski, Branko

    2016-12-20

    The objective of our study was to develop controlled drug delivery system based on erythrocyte ghosts for amphiphilic compound sodium diclofenac considering the differences between erythrocytes derived from two readily available materials - porcine slaughterhouse and outdated transfusion human blood. Starting erythrocytes, empty erythrocyte ghosts and diclofenac loaded ghosts were compared in terms of the encapsulation efficiency, drug releasing profiles, size distribution, surface charge, conductivity, surface roughness and morphology. The encapsulation of sodium diclofenac was performed by an osmosis based process - gradual hemolysis. During this process sodium diclofenac exerted mild and delayed antihemolytic effect and increased potassium efflux in porcine but not in outdated human erythrocytes. FTIR spectra revealed lack of any membrane lipid disorder and chemical reaction with sodium diclofenac in encapsulated ghosts. Outdated human erythrocyte ghosts with detected nanoscale damages and reduced ability to shrink had encapsulation efficiency of only 8%. On the other hand, porcine erythrocyte ghosts had encapsulation efficiency of 37% and relatively slow drug release rate. More preserved structure and functional properties of porcine erythrocytes related to their superior encapsulation and release performances, define them as more appropriate for the usage in sodium diclofenac encapsulation process. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. Optimization of NMR spectroscopy of encapsulated proteins dissolved in low viscosity fluids

    International Nuclear Information System (INIS)

    Nucci, Nathaniel V.; Marques, Bryan S.; Bédard, Sabrina; Dogan, Jakob; Gledhill, John M.; Moorman, Veronica R.; Peterson, Ronald W.; Valentine, Kathleen G.; Wand, Alison L.; Wand, A. Joshua

    2011-01-01

    Comprehensive application of solution NMR spectroscopy to studies of macromolecules remains fundamentally limited by the molecular rotational correlation time. For proteins, molecules larger than 30 kDa require complex experimental methods, such as TROSY in conjunction with isotopic labeling schemes that are often expensive and generally reduce the potential information available. We have developed the reverse micelle encapsulation strategy as an alternative approach. Encapsulation of proteins within the protective nano-scale water pool of a reverse micelle dissolved in ultra-low viscosity nonpolar solvents overcomes the slow tumbling problem presented by large proteins. Here, we characterize the contributions from the various components of the protein-containing reverse micelle system to the rotational correlation time of the encapsulated protein. Importantly, we demonstrate that the protein encapsulated in the reverse micelle maintains a hydration shell comparable in size to that seen in bulk solution. Using moderate pressures, encapsulation in ultra-low viscosity propane or ethane can be used to magnify this advantage. We show that encapsulation in liquid ethane can be used to reduce the tumbling time of the 43 kDa maltose binding protein from ∼23 to ∼10 ns. These conditions enable, for example, acquisition of TOCSY-type data resolved on the adjacent amide NH for the 43 kDa encapsulated maltose binding protein dissolved in liquid ethane, which is typically impossible for proteins of such size without use of extensive deuteration or the TROSY effect.

  13. PECVD-ONO: A New Deposited Firing Stable Rear Surface Passivation Layer System for Crystalline Silicon Solar Cells

    Directory of Open Access Journals (Sweden)

    M. Hofmann

    2008-01-01

    Full Text Available A novel plasma-enhanced chemical vapour deposited (PECVD stack layer system consisting of a-SiOx:H, a-SiNx:H, and a-SiOx:H is presented for silicon solar cell rear side passivation. Surface recombination velocities below 60 cm/s (after firing and below 30 cm/s (after forming gas anneal were achieved. Solar cell precursors without front and rear metallisation showed implied open-circuit voltages Voc values extracted from quasi-steady-state photoconductance (QSSPC measurements above 680 mV. Fully finished solar cells with up to 20.0% energy conversion efficiency are presented. A fit of the cell's internal quantum efficiency using software tool PC1D and a comparison to a full-area aluminium-back surface field (Al-BSF and thermal SiO2 is shown. PECVD-ONO was found to be clearly superior to Al-BSF. A separation of recombination at the metallised and the passivated area at the solar cell's rear is presented using the equations of Fischer and Kray. Nuclear reaction analysis (NRA has been used to evaluate the hydrogen depth profile of the passivation layer system at different stages.

  14. Embolization of the Systemic Arterial Supply via a Detachable Silicon Balloon in a Child with Scimitar Syndrome

    International Nuclear Information System (INIS)

    Sahin, Sinan; Celebi, Ahmet; Yalcin, Yalim; Saritas, Mustafa; Bilal, Mehmet S.; Celik, Levent

    2005-01-01

    Scimitar syndrome is a rare congenital disorder. It is characterized by partial or total abnormal venous drainage of the right lung into the inferior vena cava, which is often associated with anomalous systemic arterial supply to the right lung, congenital cardiac anomalies, hypoplasia of the right lung and bronchial anomalies. Symptoms depend on the degree of the shunt and severity of the associated anomalies, which determine the treatment. We present a 6-year-old boy who was diagnosed as having the adult form of scimitar syndrome during evaluation for recurrent pulmonary infections, and underwent embolization with a detachable silicon balloon of the anomalous systemic arterial supply from the abdominal aorta to the right lower lung lobe. Successful elective surgery was performed 6 months later, in which right pulmonary veins were directed to the left atrium using a Gore-Tex patch by creating an intra-atrial tunnel. The patient has been symptom-free period during 6 months of follow-up, which supports the idea that recurrent pulmonary infections can be eliminated by embolization of the anomalous arterial supply

  15. Development of a very fast spectral response measurement system for analysis of hydrogenated amorphous silicon solar cells and modules

    International Nuclear Information System (INIS)

    Rodríguez, J.A.; Fortes, M.; Alberte, C.; Vetter, M.; Andreu, J.

    2013-01-01

    Highlights: ► Spectral response equipment for measuring a-Si:H solar cells in a few seconds. ► Equipment based on 16 LEDs with simultaneous illumination of the solar cell. ► The current generated by each LED is analyzed by a Fast Fourier Transform. ► Cheap equipment without lock-in technology for the current measurement. ► Measurement error vs. conventional measurement less than 1% in J sc . - Abstract: An important requirement for a very fast spectral response measurement system is the simultaneous illumination of the solar cell at multiple well defined wavelengths. Nowadays this can be done by means of light emitting diodes (LEDs) available for a multitude of wavelengths. For the purpose to measure the spectral response (SR) of amorphous silicon solar cells a detailed characterization of LEDs emitting in the wavelength range from 300 nm to 800 nm was performed. In the here developed equipment the LED illumination is modulated in the frequency range from 100 Hz to 200 Hz and the current generated by each LED is analyzed by a Fast Fourier Transform (FFT) to determine the current component corresponding to each wavelength. The equipment provides a signal to noise ratio of 2–4 orders of magnitude for individual wavelengths resulting in a precise measurement of the SR over the whole wavelength range. The difference of the short circuit current determined from the SR is less than 1% in comparison to a conventional system with monochromator.

  16. Structural, optical and electrical properties of silicon nanocrystals embedded in SixC1−x/SiC multilayer systems for photovoltaic applications

    International Nuclear Information System (INIS)

    López-Vidrier, J.; Hernández, S.; Samà, J.; Canino, M.; Allegrezza, M.; Bellettato, M.; Shukla, R.; Schnabel, M.; Löper, P.; López-Conesa, L.; Estradé, S.; Peiró, F.; Janz, S.; Garrido, B.

    2013-01-01

    Highlights: ► We study the structural, optical and electrical properties of Si x C 1−x /SiC multilayers with different Si excess. ► Multilayer structure is destroyed after annealing at 1100 °C. ► Energy filtered TEM confirmed the Si NC formation. ► Sample thickness values from optical simulations are in agreement with TEM observations. ► The crystallization degree of the NCs was evaluated by Raman scattering and R and T techniques. ► The system conductivity depends on the NC size. ► The presence of a defective oxycarbide layer on top did not allow for obtaining useful electrical information. -- Abstract: In this work we present a structural, optical and electrical characterization of Si x C 1−x /SiC multilayer systems with different silicon content. After the deposition process, an annealing treatment was carried out in order to induce the silicon nanocrystals formation. By means of energy-filtered transmission electron microscopy (EFTEM) we observed the structural morphology of the multilayers and the presence of crystallized silicon nanoprecipitates for samples annealed up to 1100 °C. We discuss the suitability of optical techniques such as Raman scattering and reflectance and transmittance (R and T) for the evaluation of the crystalline fraction of our samples at different silicon excess ranges. In addition, the combination of R and T measurements with simulation has proved to be a useful instrument to confirm the structural properties observed by EFTEM. Finally, we explore the origin of the extremely high current density revealed by electrical measurements, probably due to the presence of an undesired defective SiC y O z ternary compound layer, already supported by the structural and optical results. Nevertheless, the variation of the electrical measurements with the silicon amount indicates a small but significant contribution from the multilayers

  17. Research and development of photovoltaic power system. Development of novel technologies for fabrication of high quality silicon thin films for solar cells; Taiyoko hatsuden system no kenkyu kaihatsu. Kohinshitsu silicon usumaku sakusei gijutsu

    Energy Technology Data Exchange (ETDEWEB)

    Shimizu, T [Kanazawa University, Ishikawa (Japan). Faculty of Engineering

    1994-12-01

    Described herein are the results of the FY1994 research program for development of novel technologies for fabrication of high quality thin films of silicon for solar cells. The study on the mechanisms and effects of chemical annealing reveals that the film structure greatly varies depending on substrate temperature during the hydrotreatment process, based on the tests with substrate temperature, deposition of superthin film (T1) and hydrotreatment (T2) as the variable parameters. Chemical annealing at low temperature produces a high-quality a-Si:H film of low defect content. The study on fabrication of thin polycrystalline silicon films at low temperature observes on real time the process of deposition of the thin films on polycrystalline silicon substrates, where a natural oxide film is removed beforehand from the substrate. The results indicate that a thin polycrystalline silicon film of 100% crystallinity can be formed even on a polycrystalline silicon substrate by controlling starting gas composition and substrate temperature. The layer-by-layer method is used as the means for forming the seed crystals on a glass substrate, where deposition and hydrotreatment are repeated alternately, to produce the thin crystalline silicon films of high crystallinity. 3 figs.

  18. Silicon Alloying On Aluminium Based Alloy Surface

    International Nuclear Information System (INIS)

    Suryanto

    2002-01-01

    Silicon alloying on surface of aluminium based alloy was carried out using electron beam. This is performed in order to enhance tribological properties of the alloy. Silicon is considered most important alloying element in aluminium alloy, particularly for tribological components. Prior to silicon alloying. aluminium substrate were painted with binder and silicon powder and dried in a furnace. Silicon alloying were carried out in a vacuum chamber. The Silicon alloyed materials were assessed using some techniques. The results show that silicon alloying formed a composite metal-non metal system in which silicon particles are dispersed in the alloyed layer. Silicon content in the alloyed layer is about 40% while in other place is only 10.5 %. The hardness of layer changes significantly. The wear properties of the alloying alloys increase. Silicon surface alloying also reduced the coefficient of friction for sliding against a hardened steel counter face, which could otherwise be higher because of the strong adhesion of aluminium to steel. The hardness of the silicon surface alloyed material dropped when it underwent a heating cycle similar to the ion coating process. Hence, silicon alloying is not a suitable choice for use as an intermediate layer for duplex treatment

  19. Graphene oxide-Ag nanoparticles-pyramidal silicon hybrid system for homogeneous, long-term stable and sensitive SERS activity

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Jia [School of Physics and Electronics, Shandong Normal University, Jinan 250014 (China); Xu, Shicai [Shandong Provincial Key Laboratory of Biophysics, College of Physics and Electronic Information, Dezhou University, Dezhou 253023 (China); Liu, Xiaoyun; Li, Zhe; Hu, Litao; Li, Zhen; Chen, Peixi; Ma, Yong [School of Physics and Electronics, Shandong Normal University, Jinan 250014 (China); Jiang, Shouzhen, E-mail: jiang_sz@126.com [School of Physics and Electronics, Shandong Normal University, Jinan 250014 (China); Shandong Provincial Key Laboratory of Optics and Photonic Device, Jinan 250014 (China); Ning, Tingyin [School of Physics and Electronics, Shandong Normal University, Jinan 250014 (China); Shandong Provincial Key Laboratory of Optics and Photonic Device, Jinan 250014 (China)

    2017-02-28

    Highlights: • We directly grown AgNPs on substrate by annealing method in the quartz tube. Compare with spin-coating Ag nanoparticles solution method, we got more uniform distribution of AgNPs and the AgNPs better adsorption on the substrate. • We use a simple and lost-cost method to obtain the pyramidal silicon (PSi). The PSi possessing well-separated pyramid arrays can make contribution to the homogeneity and sensitivity of the substrate. • In our work, graphene oxide (GO) film is uniformly deposited on AgNPs and PSi by using a spin-coating method. The GO films endow the hybrid system a good stability and enhance the homogeneity and sensitivity of the substrate. - Abstract: In our work, few layers graphene oxide (GO) were directly synthesized on Ag nanoparticles (AgNPs) by spin-coating method to fabricate a GO-AgNPs hybrid structure on a pyramidal silicon (PSi) substrate for surface-enhanced Raman scattering (SERS). The GO-AgNPs-PSi substrate showed excellent Raman enhancement effect, the minimum detected concentration for Rhodamine 6G (R6G) can reach 10{sup −12} M, which is one order of magnitude lower than the AgNPs-PSi substrate and two order of magnitude lower than the GO-AgNPs-flat-Si substrate. The linear fit calibration curve with error bars is presented and the value of R{sup 2} of 612 and 773 cm{sup −1} can reach 0.986 and 0.980, respectively. The excellent linear response between the Raman intensity and R6G concentrations prove that the prepared GO-AgNPs-PSi substrates can serve as good SERS substrate for molecule detection. The maximum deviations of SERS intensities from 20 positions of the GO-AgNPs-PSi substrate are less than 8%, revealing the high homogeneity of the SERS substrate. The excellent homogeneity of the enhanced Raman signals can be attributed to well-separated pyramid arrays of PSi, the uniform morphology of AgNPs and multi-functions of GO layer. Besides, the uniform GO film can effectively protect AgNPs from oxidation and endow

  20. Nutritional management of encapsulating peritoneal sclerosis with ...

    African Journals Online (AJOL)

    Keywords: intradialytic parenteral nutrition, nutritional management, encapsulating peritoneal sclerosis ... reflection of fluid retention and the underlying inflammatory process, ... The patient appeared weak and frail, with severe generalised muscle ... was recommended on diagnosis of EPS to prevent further peritoneal.

  1. Encapsulated oligodendrocyte precursor cell fate is dependent on PDGF-AA release kinetics in a 3D microparticle-hydrogel drug delivery system.

    Science.gov (United States)

    Pinezich, Meghan R; Russell, Lauren N; Murphy, Nicholas P; Lampe, Kyle J

    2018-04-16

    Biomaterial drug delivery systems (DDS) can be used to regulate growth factor release and combat the limited intrinsic regeneration capabilities of central nervous system (CNS) tissue following injury and disease. Of particular interest are systems that aid in oligodendrocyte regeneration, as oligodendrocytes generate myelin which surrounds neuronal axons and helps transmit signals throughout the CNS. Oligodendrocyte precursor cells (OPCs) are found in small numbers in the adult CNS, but are unable to effectively differentiate following CNS injury. Delivery of signaling molecules can initiate a favorable OPC response, such as proliferation or differentiation. Here, we investigate the delivery of one such molecule, platelet derived growth factor-AA (PDGF-AA), from poly(lactic-co-glycolic) acid microparticles to OPCs in a 3D polyethylene glycol-based hydrogel. The goal of this DDS was to better understand the relationship between PDGF-AA release kinetics and OPC fate. The system approximates native brain tissue stiffness, while incorporating PDGF-AA under seven different delivery scenarios. Within this DDS, supply of PDGF-AA followed by PDGF-AA withdrawal caused OPCs to upregulate gene expression of myelin basic protein (MBP) by factors of 1.6-9.2, whereas continuous supply of PDGF-AA caused OPCs to remain proliferative. At the protein expression level, we observed an upregulation in O1, a marker for mature oligodendrocytes. Together, these results show that burst release followed by withdrawal of PDGF-AA from a hydrogel DDS stimulates survival, proliferation, and differentiation of OPCs in vitro. Our results could inform the development of improved neural regeneration strategies that incorporate delivery of PDGF-AA to the injured CNS. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2018. © 2018 Wiley Periodicals, Inc.

  2. Encapsulated Bacillus anthracis interacts closely with liver endothelium.

    Science.gov (United States)

    Piris-Gimenez, Alejandro; Corre, Jean-Philippe; Jouvion, Gregory; Candela, Thomas; Khun, Huot; Goossens, Pierre L

    2009-11-01

    The Bacillus anthracis poly-gamma-D-glutamate capsule is essential for virulence. It impedes phagocytosis and protects bacilli from the immune system, thus promoting systemic dissemination. To further define the virulence mechanisms brought into play by the capsule, we characterized the interactions between encapsulated nontoxinogenic B. anthracis and its host in vivo through histological analysis, perfusion, and competition experiments with purified capsule. Clearance of encapsulated bacilli from the blood was rapid (>90% clearance within 5 min), with 75% of the bacteria being trapped in the liver. Competition experiments with purified capsule polyglutamate inhibited this interaction. At the septicemic phase of cutaneous infection with spores, the encapsulated bacilli were trapped in the vascular spaces of the liver and interacted closely with the liver endothelium in the sinusoids and terminal and portal veins. They often grow as microcolonies containing capsular material shed by the bacteria. We show that, in addition to its inhibitory effect on the interaction with the immune system, the capsule surrounding B. anthracis plays an active role in mediating the trapping of the bacteria within the liver and may thus contribute to anthrax pathogenesis. Because other microorganisms produce polyglutamate, it may also represent a general mechanism of virulence or in vivo survival.

  3. Charging-discharging characteristics of macro-encapsulated phase change materials in an active thermal energy storage system for a solar drying kiln

    Directory of Open Access Journals (Sweden)

    Kumar Shailendra

    2017-01-01

    Full Text Available The present study explores suitability of two phase change materials (PCM for development of an active thermal storage system for a solar drying kiln by studying their melting and solidification behaviors. A double glass glazing prototype solar kiln was used in the study. The storage system consisted of a water storage tank with PCM placed inside the water in high density polyethylene containers. The water in the tank was heated with help of solar energy using an evacuated tube collector array. The melting and solidification temperature curves of PCM were obtained by charging and discharging the water tank. The study illustrated the utility of the PCM in using the stored thermal energy during their discharge to enhance the temperature inside the kiln. The rate of temperature reduction was found to be higher for paraffin wax as compared to a fatty acid based PCM. The water temperature during the discharge of the PCM showed dependence on the discharge characteristics of each PCM suggesting their suitability in designing active thermal storage systems.

  4. Reversed phase HPLC analysis of stability and microstructural effects on degradation kinetics of β-carotene encapsulated in freeze-dried maltodextrin-emulsion systems.

    Science.gov (United States)

    Harnkarnsujarit, Nathdanai; Charoenrein, Sanguansri; Roos, Yrjö H

    2012-09-26

    Degradation of dispersed lipophilic compounds in hydrophilic solids depends upon matrix stability and lipid physicochemical properties. This study investigated effects of solid microstructure and size of lipid droplets on the stability of dispersed β-carotene in freeze-dried systems. Emulsions of β-carotene in sunflower oil were dispersed in maltodextrin systems (M040/DE6, M100/DE11, and M250/DE25.5) (8% w/w oil) and prefrozen at various freezing conditions prior to freeze-drying to control nucleation and subsequent pore size and structural collapse of freeze-dried solids. The particle size, physical state, and β-carotene contents of freeze-dried emulsions were measured during storage at various water activity (a(w)) using a laser particle size analyzer, differential scanning calorimeter, and high performance liquid chromatography (HPLC), respectively. The results showed that M040 stabilized emulsions in low temperature freezing exhibited lipid crystallization. Collapse of solids in storage at a(w) which plasticized systems to the rubbery state led to flow and increased the size of oil droplets. Degradation of β-carotene analyzed using a reversed-phase C(30) column followed first-order kinetics. Porosity of solids had a major effect on β-carotene stability; however, the highest stability was found in fully plasticized and collapsed solids.

  5. Sclerosing encapsulating peritonitis: a case report

    Energy Technology Data Exchange (ETDEWEB)

    Candido, Paula de Castro Menezes; Werner, Andrea de Freitas; Pereira, Izabela Machado Flores; Matos, Breno Assuncao; Pfeilsticker, Rudolf Moreira; Silva Filho, Raul, E-mail: paulacmcandido@yahoo.com.br [Hospital Felicio Rocho, Belo Horizonte, MG (Brazil)

    2015-01-15

    Sclerosing encapsulating peritonitis, a rare cause of bowel obstruction, was described as a complication associated with peritoneal dialysis which is much feared because of its severity. The authors report a case where radiological findings in association with clinical symptoms have allowed for a noninvasive diagnosis of sclerosing encapsulating peritonitis, emphasizing the high sensitivity and specificity of computed tomography to demonstrate the characteristic findings of such a condition. (author)

  6. Silicon PIN diode based electron-gamma coincidence detector system for Noble Gases monitoring.

    Science.gov (United States)

    Khrustalev, K; Popov, V Yu; Popov, Yu S

    2017-08-01

    We present a new second generation SiPIN based electron-photon coincidence detector system developed by Lares Ltd. for use in the Noble Gas measurement systems of the International Monitoring System and the On-site Inspection verification regimes of the Comprehensive Nuclear-Test Ban Treaty (CTBT). The SiPIN provide superior energy resolution for electrons. Our work describes the improvements made in the second generation detector cells and the potential use of such detector systems for other applications such as In-Situ Kr-85 measurements for non-proliferation purposes. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Hayabusa2 Sample Catcher and Container: Metal-Seal System for Vacuum Encapsulation of Returned Samples with Volatiles and Organic Compounds Recovered from C-Type Asteroid Ryugu

    Science.gov (United States)

    Okazaki, Ryuji; Sawada, Hirotaka; Yamanouchi, Shinji; Tachibana, Shogo; Miura, Yayoi N.; Sakamoto, Kanako; Takano, Yoshinori; Abe, Masanao; Itoh, Shoichi; Yamada, Keita; Yabuta, Hikaru; Okamoto, Chisato; Yano, Hajime; Noguchi, Takaaki; Nakamura, Tomoki; Nagao, Keisuke

    2017-07-01

    The spacecraft Hayabusa2 was launched on December 3, 2014, to collect and return samples from a C-type asteroid, 162173 Ryugu (provisional designation, 1999 JU3). It is expected that the samples collected contain organic matter and water-bearing minerals and have key information to elucidate the origin and history of the Solar System and the evolution of bio-related organics prior to delivery to the early Earth. In order to obtain samples with volatile species without terrestrial contamination, based on lessons learned from the Hayabusa mission, the sample catcher and container of Hayabusa2 were refined from those used in Hayabusa. The improvements include (1) a mirror finish of the inner wall surface of the sample catcher and the container, (2) adoption of an aluminum metal sealing system, and (3) addition of a gas-sampling interface for gas collection and evacuation. The former two improvements were made to limit contamination of the samples by terrestrial atmosphere below 1 Pa after the container is sealed. The gas-sampling interface will be used to promptly collect volatile species released from the samples in the sample container after sealing of the container. These improvements maintain the value of the returned samples.

  8. Co-encapsulation of curcumin and resveratrol into novel nutraceutical hyalurosomes nano-food delivery system based on oligo-hyaluronic acid-curcumin polymer.

    Science.gov (United States)

    Guo, Chunjing; Yin, Jungang; Chen, Daquan

    2018-02-01

    In this work, in order to enhance the stability, bioavailability and antioxidant activity of insoluble antioxidants used into juice, yoghourt and nutritional supplements, the oligo-hyalurosomes nano-delivery system (CRHs) based on oligo-hyaluronic acid -curcumin (oHC) polymer loaded curcumin(Cur) and resveratrol (Res) was fabricated with new nanotechnolgy. The rosy biodegradable amphiphilic oHC polymer was successfully synthesized and used to fabricate the hyalurosomes containing both Cur and Res, called CRHs. The CRHs can spontaneously self-assemble into nano-sized spherical shape of average particle size 134.5±5.1nm and Zeta potential -29.4±1.2 at pH 7.4 PBS conditions. In vitro gastrointestinal release test showed a perfect stability and outstanding sustained release character. Moreover, compared to the single formulations and liposomes, CRHs showed a dose-dependent manner with a higher radical scavenging activity. Therefore, the novel CRHs nano-food manifested the hopeful properties for the new effective gastrointestinal formulation and promising new nano-food delivery system in the use of juice, yoghourt and nutritional supplements. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Challenges of arbitrary waveform signal detection by Silicon Photomultipliers as readout for Cherenkov fibre based beam loss monitoring systems

    CERN Document Server

    Vinogradov, Sergey; Nebot del Busto, Eduardo; Kastriotou, Maria; Welsch, Carsten P

    2016-01-01

    Silicon Photomultipliers (SiPMs) are well recognised as very competitive photodetectors due to their exceptional photon number and time resolution, room-temperature low-voltage operation, insensitivity to magnetic fields, compactness, and robustness. Detection of weak light pulses of nanosecond time scale appears to be the best area for SiPM applications because in this case most of the SiPM drawbacks have a rather limited effect on its performance. In contrast to the more typical scintillation and Cherenkov detection applications, which demand information on the number of photons and/or the arrival time of the light pulse only, beam loss monitoring (BLM) systems utilising Cherenkov fibres with photodetector readout have to precisely reconstruct the temporal profile of the light pulse. This is a rather challenging task for any photon detector especially taking into account the high dynamic range of incident signals (100K – 1M) from a few photons to a few percents of destructive losses in a beam line and pre...

  10. The upgrade of the ALICE Inner Tracking System - Status of the R&D; on monolithic silicon pixel sensors

    CERN Document Server

    Van Hoorne, Jacobus Willem

    2014-01-01

    s a major part of its upgrade plans, the ALICE experiment schedules the installation of a novel Inner Tracking System (ITS) during the Long Shutdown 2 (LS2) of the LHC in 2018/19. It will replace the present silicon tracker with seven layers of Monolithic Active Pixel Sensors (MAPS) and significantly improve the detector performance in terms of tracking and rate capabilities. The choice of technology has been guided by the tight requirements on the material budget of 0 : 3 % X = X 0 /layer for the three innermost layers and backed by the significant progress in the field of MAPS in recent years. The pixel chips are manufactured in the TowerJazz 180 nm CMOS imaging sensor process on wafers with a high resistivity epitaxial layer. Within the ongoing R&D; phase, several sensor chip prototypes have been developed and produced on different epitaxial layer thicknesses and resistivities. These chips are being characterized for their performance before and after irradiation using source tests, test beam and measu...

  11. Computational uncertainties in silicon dioxide/plutonium intermediate neutron spectrum systems

    International Nuclear Information System (INIS)

    Jaegers, P.J.

    1997-01-01

    In the past several years, several proposals have been made for the long-term stabilization and storage of surplus fissile materials. Many of these proposed scenarios involve systems that have an intermediate neutron energy spectrum. Such intermediate-energy systems are dominated by scattering and fission events induced by neutrons ranging in energy from 1 eV to 100keV. To ensure adequate safety margins and cost effectiveness, it is necessary to have benchmark data for these intermediate-energy spectrum systems; however, a review of the nuclear criticality benchmarks indicates that no formal benchmarks are available. Nuclear data uncertainties have been reported for some types of intermediate-energy spectrum systems. Using a variety of Monte Carlo computer codes and cross-section sets, reported significant variations in the calculated k ∞ of intermediate-energy spectrum metal/ 235 U systems. We discuss the characteristics of intermediate neutron spectrum systems and some of the computational differences that can occur in calculating the k eff of these systems

  12. Nanoscale encapsulation: the structure of cations in hydrophobic microporous aluminosilicates

    International Nuclear Information System (INIS)

    Wasserman, S.R.; Yuchs, S.E.; Giaquinta, D.; Soderholm, L.; Song, Kang.

    1996-01-01

    Hydrophobic microporous aluminosilicates, created by organic surface modification of inherently hydrophilic materials such as zeolites and clays, are currently being investigated as storage media for hazardous cations. Use of organic monolayers to modify the surface of an aluminosilicate after introducing an ion into the zeolite/clay reduces the interaction of water with the material. Resulting systems are about 20 times more resistant to leaching of stored ion. XAS spectra from the encapsulated ion demonstrate that byproducts from the organic modifier can complex with the stored cation. This complexation can result in a decreased affinity of the cation for the aluminosilicate matrix. Changing the organic modifier eliminates this problem. XAS spectra also indicate that the reactivity and speciation of the encapsulated ion may change upon application of the hydrophobic layer

  13. Silicon microgyroscope temperature prediction and control system based on BP neural network and Fuzzy-PID control method

    International Nuclear Information System (INIS)

    Xia, Dunzhu; Kong, Lun; Hu, Yiwei; Ni, Peizhen

    2015-01-01

    We present a novel silicon microgyroscope (SMG) temperature prediction and control system in a narrow space. As the temperature of SMG is closely related to its drive mode frequency and driving voltage, a temperature prediction model can be established based on the BP neural network. The simulation results demonstrate that the established temperature prediction model can estimate the temperature in the range of −40 to 60 °C with an error of less than ±0.05 °C. Then, a temperature control system based on the combination of fuzzy logic controller and the increment PID control method is proposed. The simulation results prove that the Fuzzy-PID controller has a smaller steady state error, less rise time and better robustness than the PID controller. This is validated by experimental results that show the Fuzzy-PID control method can achieve high precision in keeping the SMG temperature stable at 55 °C with an error of less than 0.2 °C. The scale factor can be stabilized at 8.7 mV/°/s with a temperature coefficient of 33 ppm °C −1 . ZRO (zero rate output) instability is decreased from 1.10°/s (9.5 mV) to 0.08°/s (0.7 mV) when the temperature control system is implemented over an ambient temperature range of −40 to 60 °C. (paper)

  14. Tracking hypoxic signaling within encapsulated cell aggregates.

    Science.gov (United States)

    Skiles, Matthew L; Sahai, Suchit; Blanchette, James O

    2011-12-16

    In Diabetes mellitus type 1, autoimmune destruction of the pancreatic β-cells results in loss of insulin production and potentially lethal hyperglycemia. As an alternative treatment option to exogenous insulin injection, transplantation of functional pancreatic tissue has been explored. This approach offers the promise of a more natural, long-term restoration of normoglycemia. Protection of the donor tissue from the host's immune system is required to prevent rejection and encapsulation is a method used to help achieve this aim. Biologically-derived materials, such as alginate and agarose, have been the traditional choice for capsule construction but may induce inflammation or fibrotic overgrowth which can impede nutrient and oxygen transport. Alternatively, synthetic poly(ethylene glycol) (PEG)-based hydrogels are non-degrading, easily functionalized, available at high purity, have controllable pore size, and are extremely biocompatible. As an additional benefit, PEG hydrogels may be formed rapidly in a simple photo-crosslinking reaction that does not require application of non-physiological temperatures. Such a procedure is described here. In the crosslinking reaction, UV degradation of the photoinitiator, 1-[4-(2-Hydroxyethoxy)-phenyl]-2-hydroxy-2-methyl-1-propane-1-one (Irgacure 2959), produces free radicals which attack the vinyl carbon-carbon double bonds of dimethacrylated PEG (PEGDM) inducing crosslinking at the chain ends. Crosslinking can be achieved within 10 minutes. PEG hydrogels constructed in such a manner have been shown to favorably support cells, and the low photoinitiator concentration and brief exposure to UV irradiation is not detrimental to viability and function of the encapsulated tissue. While we methacrylate our PEG with the method described below, PEGDM can also be directly purchased from vendors such as Sigma. An inherent consequence of encapsulation is isolation of the cells from a vascular network. Supply of nutrients, notably oxygen

  15. Rapid fabrication of Al{sub 2}O{sub 3} encapsulations for organic electronic devices

    Energy Technology Data Exchange (ETDEWEB)

    Ali, Kamran; Ali, Junaid [Department of Mechatronics Engineering, Jeju National University, Jeju 690-756 (Korea, Republic of); Mehdi, Syed Murtuza [Department of Mechanical Engineering, NED University of Engineering and Technology, Karachi 75270 (Pakistan); Choi, Kyung-Hyun, E-mail: amm@jejunu.ac.kr [Department of Mechatronics Engineering, Jeju National University, Jeju 690-756 (Korea, Republic of); An, Young Jin [Jeonnam Science and Technology Promotion Center, Yeongam-gun, Jeollanam-do 526-897 (Korea, Republic of)

    2015-10-30

    Highlights: • Al{sub 2}O{sub 3} encapsulations are being developed through a unique R2R-AALD system. • The encapsulations have resulted in life time enhancement of PVP memristor devices. • The Al{sub 2}O{sub 3} encapsulated memristor performed with superior stability for four weeks. • Encapsulated devices performed efficiently even after bending test for 100 cycles. - Abstract: Organic electronics have earned great reputation in electronic industry yet they suffer technical challenges such as short lifetimes and low reliability because of their susceptibility to water vapor and oxygen which causes their fast degradation. This paper report on the rapid fabrication of Al{sub 2}O{sub 3} encapsulations through a unique roll-to-roll atmospheric atomic layer deposition technology (R2R-AALD) for the life time enhancement of organic poly (4-vinylphenol) (PVP) memristor devices. The devices were then categorized into two sets. One was processed with R2R-AALD Al{sub 2}O{sub 3} encapsulations at 50 °C and the other one was kept as un-encapsulated. The field-emission scanning electron microscopy (FESEM) results revealed that pin holes and other irregularities in PVP films with average arithmetic roughness (R{sub a}) of 9.66 nm have been effectively covered by Al{sub 2}O{sub 3} encapsulation having R{sub a} of 0.92 nm. The X-ray photoelectron spectroscopy XPS spectrum for PVP film showed peaks of C 1s and O 1s at the binding energies of 285 eV and 531 eV, respectively. The respective appearance of Al 2p, Al 2s, and O 1s peaks at the binding energies of 74 eV, 119 eV, and 531 eV, confirms the fabrication of Al{sub 2}O{sub 3} films. Electrical current–voltage (I–V) measurements confirmed that the Al{sub 2}O{sub 3} encapsulation has a huge influence on the performance, robustness and life time of memristor devices. The Al{sub 2}O{sub 3} encapsulated memristor performed with superior stability for four weeks whereas the un-encapsulated devices could only last for one

  16. Encapsulation of aluminium in geopolymers produced from metakaolin

    Energy Technology Data Exchange (ETDEWEB)

    Kuenzel, C. [Department of Civil and Environmental Engineering, Imperial College London (United Kingdom); Centre for Advanced Structural Ceramics, Department of Materials, Imperial College London (United Kingdom); Neville, T.P. [Centre for CO_2 Technology, Department of Chemical Engineering, University College London (United Kingdom); Omakowski, T. [Flowcrete, Group Ltd., Cheshire (United Kingdom); Vandeperre, L. [Centre for Advanced Structural Ceramics, Department of Materials, Imperial College London (United Kingdom); Boccaccini, A.R. [Institute of Biomaterials, University of Erlangen-Nuremberg (Germany); Bensted, J.; Simons, S.J.R. [Centre for CO_2 Technology, Department of Chemical Engineering, University College London (United Kingdom); Cheeseman, C.R., E-mail: c.cheeseman@imperial.ac.uk [Department of Civil and Environmental Engineering, Imperial College London (United Kingdom)

    2014-04-01

    Magnox swarf contaminated with trace levels of Al metal is an important UK legacy waste originated from the fuel rod cladding system used in Magnox nuclear power stations. Composite cements made from Portland cement and blast furnace slag form a potential encapsulation matrix. However the high pH of this system causes the Al metal to corrode causing durability issues. Geopolymers derived from metakaolin are being investigated as an alternative encapsulation matrix for Magnox swarf waste and the corrosion kinetics and surface interactions of Al with metakaolin geopolymer are reported in this paper. It is shown that the pH of the geopolymer paste can be controlled by the selection of metakaolin and the sodium silicate solution used to form the geopolymer. A decrease in pH of the activation solution reduces corrosion of the Al metal and increases the stability of bayerite and gibbsite layers formed on the Al surface. The bayerite and gibbsite act as a passivation layer which inhibits further corrosion and mitigates H{sub 2} generation. The research shows that optimised metakaolin geopolymers have potential to be used to encapsulate legacy Magnox swarf wastes.

  17. A novel laser alignment system for tracking detectors using transparent silicon strip sensors

    International Nuclear Information System (INIS)

    Blum, W.; Kroha, H.; Widmann, P.

    1995-02-01

    Modern large-area precision tracking detectors require increasing accuracy of the geometrical alignment over large distances. A novel optical multi-point alignment system has been developed for the muon spectrometer of the ATLAS detector at the Large Hadron Collider. The system uses collimated laser beams as alignment references which are monitored by semi-transparent optical position sensors. The custom designed sensors provide very precise and uniform position information on the order of 1 μm over a wide measurement range. At suitable laser wavelengths, produced by laser diodes, transmission rates above 90% have been achieved which allow to align more than 30 sensors along one laser beam. With this capability and equipped with integrated readout electronics, the alignment system offers high flexibility for precision applications in a wide range of detector systems. (orig.)

  18. Design and fabrication of a foldable 3D silicon based package for solid state lighting applications

    International Nuclear Information System (INIS)

    Sokolovskij, R; Liu, P; Van Zeijl, H W; Mimoun, B; Zhang, G Q

    2015-01-01

    Miniaturization of solid state lighting (SSL) luminaires as well as reduction of packaging and assembly costs are of prime interest for the SSL lighting industry. A novel silicon based LED package for lighting applications is presented in this paper. The proposed design consists of 5 rigid Si tiles connected by flexible polyimide hinges with embedded interconnects (ICs). Electrical, optical and thermal characteristics were taken into consideration during design. The fabrication process involved polyimide (PI) application and patterning, aluminium interconnect integration in the flexible hinge, LED reflector cavity formation and metalization followed by through wafer DRIE etching for chip formation and release. A method to connect chip front to backside without TSVs was also integrated into the process. Post-fabrication wafer level assembly included LED mounting and wirebond, phosphor-based colour conversion and silicone encapsulation. The package formation was finalized by vacuum assisted wrapping around an assembly structure to form a 3D geometry, which is beneficial for omnidirectional lighting. Bending tests were performed on the flexible ICs and optical performance at different temperatures was evaluated. It is suggested that 3D packages can be expanded to platforms for miniaturized luminaire applications by combining monolithic silicon integration and system-in-package (SiP) technologies. (paper)

  19. The influence of initial defects on mechanical stress and deformation distribution in oxidized silicon

    Directory of Open Access Journals (Sweden)

    Kulinich O. A.

    2008-10-01

    Full Text Available The near-surface silicon layers in silicon – dioxide silicon systems with modern methods of research are investigated. It is shown that these layers have compound structure and their parameters depend on oxidation and initial silicon parameters. It is shown the influence of initial defects on mechanical stress and deformation distribution in oxidized silicon.

  20. Solidification interface shape control in a continuous Czochralski silicon growth system

    Science.gov (United States)

    Wang, Chenlei; Zhang, Hui; Wang, Tihu; Zheng, Lili

    2006-01-01

    In a continuous Czochralski (CCZ) growth system with a shallow and replenished melt proposed earlier, large-diameter crystals may be grown at a high pull rate and reduced melt convection. The proposed system consists of two heaters. In this paper, the relationship between the solidification interface and the power levels is established. An interface control algorithm is developed to achieve the desired interface shape by adjusting the power level of the bottom heater. The control algorithm is incorporated into an existing process model, and the efficiency of the control algorithm is tested.

  1. Advanced diffusion system for low contamination in-line rapid thermal processing of silicon solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Biro, D.; Preu, R.; Schultz, O.; Peters, S.; Huljic, D.M.; Zickermann, D.; Schindler, R.; Luedemann, R.; Willeke, G. [Fraunhofer Institute for Solar Energy Systems ISE, Freiburg (Germany)

    2002-10-01

    A novel diffusion system for in-line rapid thermal diffusion is presented. The lamp-heated furnace has a low thermal mass and a metal free transport system based on the walking beam principle. The furnace has been used to process first solar cells with lightly and highly doped emitters respectively. Solar cells with shallow lightly doped emitters show that the emitters processed in the new device can be well passivated. Shallow emitters with sheet resistances of up to 40/sq. have been contacted successfully by means of screen printing and firing through a SiN{sub x} antireflection coating. (author)

  2. Encapsulation in the food industry: a review.

    Science.gov (United States)

    Gibbs, B F; Kermasha, S; Alli, I; Mulligan, C N

    1999-05-01

    Encapsulation involves the incorporation of food ingredients, enzymes, cells or other materials in small capsules. Applications for this technique have increased in the food industry since the encapsulated materials can be protected from moisture, heat or other extreme conditions, thus enhancing their stability and maintaining viability. Encapsulation in foods is also utilized to mask odours or tastes. Various techniques are employed to form the capsules, including spray drying, spray chilling or spray cooling, extrusion coating, fluidized bed coating, liposome entrapment, coacervation, inclusion complexation, centrifugal extrusion and rotational suspension separation. Each of these techniques is discussed in this review. A wide variety of foods is encapsulated--flavouring agents, acids bases, artificial sweeteners, colourants, preservatives, leavening agents, antioxidants, agents with undesirable flavours, odours and nutrients, among others. The use of encapsulation for sweeteners such as aspartame and flavours in chewing gum is well known. Fats, starches, dextrins, alginates, protein and lipid materials can be employed as encapsulating materials. Various methods exist to release the ingredients from the capsules. Release can be site-specific, stage-specific or signalled by changes in pH, temperature, irradiation or osmotic shock. In the food industry, the most common method is by solvent-activated release. The addition of water to dry beverages or cake mixes is an example. Liposomes have been applied in cheese-making, and its use in the preparation of food emulsions such as spreads, margarine and mayonnaise is a developing area. Most recent developments include the encapsulation of foods in the areas of controlled release, carrier materials, preparation methods and sweetener immobilization. New markets are being developed and current research is underway to reduce the high production costs and lack of food-grade materials.

  3. Plastic encapsulated, dye sensitised photovoltaic cells

    Energy Technology Data Exchange (ETDEWEB)

    Potter, R.J.; Otley, L.C.; Durrant, J.R.; Haque, S.; Xu, C. [Imperial College of Science, Technology and Medicine, London (United Kingdom); Holmes, A.B.; Park, T.; Schulte, N. [Cambridge Univ. (United Kingdom)

    2004-07-01

    The report presents the results of a collaborative project that aimed to demonstrate the technical feasibility of a plastic-encapsulated, solid state, dye-sensitised solar cell (DSSC) with an energy conversion efficiency (ECE) of at least 3%. DSSCs offer a possible 'step change' in photovoltaic technology resulting in lower costs compared with existing technologies. The project involved a series of eight main tasks: the development of first and second generation HTM electrolytes; the development of polymer-supported electrolytes; the development of low temperature electrode coating procedures; dye development; cell assembly and testing; component integration; and overall process development. A wide range of innovative HTMs have been synthesised, including materials incorporating both hole-transporting and ion-chelating functional groups. The ruthenium-based dye, N3, remained the preferred sensitising component. The project has produced a system that can routinely achieve over 5% ECE at 0.1 Sun illumination on 1 cm{sup 2} cells using polymer-supported electrolytes.

  4. Comparison of silicon drift detectors made by Amptek and PNDetectors in application to the PHA system for W7-X

    Directory of Open Access Journals (Sweden)

    Krawczyk Natalia

    2016-12-01

    Full Text Available The paper presents comparison of two silicon drift detectors (SDD, one made by Amptek, USA, and the second one by PNDetector, Germany, which are considered for a soft X-ray diagnostic system for W7-X. The sensitive area of the first one is 7 mm2 × 450 μm and the second one is 10 mm2 × 450 μm. The first detector is cooled by a double-stage Peltier element, while the second detector is cooled by single-stage Peltier element. Each one is equipped with a field-effect transistor (FET. In the detector from Amptek, the FET is mounted separately, while in the detector from PNDetector, the FET is integrated on the chip. The nominal energy resolution given by the producers of the first and the second one is 136 eV@5.9 keV (at -50°C and 132 eV@5.9 keV (at -20°C, respectively. Owing to many advantages, the investigated detectors are good candidates for soft X-ray measurements in magnetic confinement devices. They are suitable for soft X-ray diagnostics, like the pulse height analysis (PHA system for the stellarator Wendelstein 7-X, which has been developed and manufactured at the Institute of Plasma Physics and Laser Microfusion (IPPLM, Warsaw, in collaboration with the Max Planck Institute for Plasma Physics (IPP, Greifswald. The diagnostic is important for the measurements of plasma electron temperature, impurities content, and possible suprathermal tails in the spectra. In order to choose the best type of detector, analysis of technical parameters and laboratory tests were done. Detailed studies show that the most suitable detector for the PHA diagnostics is the PNDetector.

  5. Development of a very fast spectral response measurement system for analysis of hydrogenated amorphous silicon solar cells and modules

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez, J.A., E-mail: jose.rodriguez@tsolar.eu [Dept. Technology, Development and Innovation, T-Solar Global S.A., Parque Tecnologico de Galicia, Avda. de Vigo 5, E-32900 San Cibrao das Vinas (Ourense) (Spain); Fortes, M. [Departamento de Electronica e Computacion, Universidade de Santiago de Compostela, 15782 Santiago de Compostela (Spain); Alberte, C.; Vetter, M.; Andreu, J. [Dept. Technology, Development and Innovation, T-Solar Global S.A., Parque Tecnologico de Galicia, Avda. de Vigo 5, E-32900 San Cibrao das Vinas (Ourense) (Spain)

    2013-01-01

    Highlights: Black-Right-Pointing-Pointer Spectral response equipment for measuring a-Si:H solar cells in a few seconds. Black-Right-Pointing-Pointer Equipment based on 16 LEDs with simultaneous illumination of the solar cell. Black-Right-Pointing-Pointer The current generated by each LED is analyzed by a Fast Fourier Transform. Black-Right-Pointing-Pointer Cheap equipment without lock-in technology for the current measurement. Black-Right-Pointing-Pointer Measurement error vs. conventional measurement less than 1% in J{sub sc}. - Abstract: An important requirement for a very fast spectral response measurement system is the simultaneous illumination of the solar cell at multiple well defined wavelengths. Nowadays this can be done by means of light emitting diodes (LEDs) available for a multitude of wavelengths. For the purpose to measure the spectral response (SR) of amorphous silicon solar cells a detailed characterization of LEDs emitting in the wavelength range from 300 nm to 800 nm was performed. In the here developed equipment the LED illumination is modulated in the frequency range from 100 Hz to 200 Hz and the current generated by each LED is analyzed by a Fast Fourier Transform (FFT) to determine the current component corresponding to each wavelength. The equipment provides a signal to noise ratio of 2-4 orders of magnitude for individual wavelengths resulting in a precise measurement of the SR over the whole wavelength range. The difference of the short circuit current determined from the SR is less than 1% in comparison to a conventional system with monochromator.

  6. Cytokine production induced by non-encapsulated and encapsulated Porphyromonas gingivalis strains

    NARCIS (Netherlands)

    Kunnen, A.; Dekker, D.C.; van Pampus, M.G.; Harmsen, H.J.; Aarnoudse, J.G.; Abbas, F.; Faas, M.M.

    Objective: Although the exact reason is not known, encapsulated gram-negative Porphyromonas gingivalis strains are more virulent than non-encapsulated strains. Since difference in virulence properties may be due to difference in cytokine production following recognition of the bacteria or their

  7. The Silicon Trypanosome : A Test Case of Iterative Model Extension in Systems Biology

    NARCIS (Netherlands)

    Achcar, Fiona; Fadda, Abeer; Haanstra, Jurgen R.; Kerkhoven, Eduard J.; Kim, Dong-Hyun; Leroux, Alejandro E.; Papamarkou, Theodore; Rojas, Federico; Bakker, Barbara M.; Barrett, Michael P.; Clayton, Christine; Girolami, Mark; Krauth-Siegel, R. Luise; Matthews, Keith R.; Breitling, Rainer; Poole, RK

    2014-01-01

    The African trypanosome, Ttypanosoma brucei, is a unicellular parasite causing African Trypanosomiasis (sleeping sickness in humans and nagana in animals). Due to some of its unique properties, it has emerged as a popular model organism in systems biology. A predictive quantitative model of

  8. Optical Characterization of Tissue Phantoms Using a Silicon Integrated fdNIRS System on Chip.

    Science.gov (United States)

    Sthalekar, Chirag C; Miao, Yun; Koomson, Valencia Joyner

    2017-04-01

    An interface circuit with signal processing and digitizing circuits for a high frequency, large area avalanche photodiode (APD) has been integrated in a 130 nm BiCMOS chip. The system enables the absolute oximetry of tissue using frequency domain Near Infrared Spectroscopy (fdNIRS). The system measures the light absorbed and scattered by the tissue by measuring the reduction in the amplitude of signal and phase shift introduced between the light source and detector which are placed a finite distance away from each other. The received 80 MHz RF signal is downconverted to a low frequency and amplified using a heterodyning scheme. The front-end transimpedance amplifier has a 3-level programmable gain that increases the dynamic range to 60 dB. The phase difference between an identical reference channel and the optical channel is measured with a 0.5° accuracy. The detectable current range is [Formula: see text] and with a 40 A/W reponsivity using the APD, power levels as low as 500 pW can be detected. Measurements of the absorption and reduced scattering coefficients of solid tissue phantoms using this system are compared with those using a commercial instrument with differences within 30%. Measurement of a milk based liquid tissue phantom show an increase in absorption coefficient with addition of black ink. The miniaturized circuit serves as an efficiently scalable system for multi-site detection for applications in neonatal cerebral oximetry and optical mammography.

  9. Report on 1979 result of Sunshine Project. R and D on solar power generation system (R and D on particle non-accelerated growth type silicon thin film crystal); 1979 nendo taiyoko hatsuden system no kenkyu kaihatsu seika hokokusho. Ryushi hikasoku seichogata silicon usumaku kessho no kenkyu kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1980-03-01

    The R and D was intended to establish the manufacturing technology of a particle non-accelerated growth type silicon thin film crystal, for the purpose of developing a technology for enabling the production of a solar power generation system, whose price is practically 1/100 compared with that of building the system with the current technology, and the R and D was also intended to build the system using such silicon material. While a simple purification method was examined for a low purity metallurgical-grade silicon, a solar-grade silicon (SOG) was developed as the new material this year, with a solar cell experimentally manufactured having a structure directly joined to the substrate material and with evaluation carried out on the characteristic of such solar cell. The application of 'gettering' was tried which was for removing harmful impurities from the substrate obtained from such material, bringing an outlook of manufacturing a solar cell with a conversion efficiency of 10%. Concerning the SOG-Si, the efficiency of 13% or higher was attained through the improvement of the manufacturing process. This was the value comparable to the case of using a conventional high purity monocrystal wafer. Further, the application of an ion implantation method was studied for the purpose of getting a low cost. (NEDO)

  10. Elastin-like polypeptides: the power of design for smart cell encapsulation.

    Science.gov (United States)

    Bandiera, Antonella

    2017-01-01

    Cell encapsulation technology is still a challenging issue. Innovative methodologies such as additive manufacturing, and alternative bioprocesses, such as cell therapeutic delivery, where cell encapsulation is a key tool are rapidly gaining importance for their potential in regenerative medicine. Responsive materials such as elastin-based recombinant expression products have features that are particularly attractive for cell encapsulation. They can be designed and tailored to meet desired requirements. Thus, they represent promising candidates for the development of new concept-based materials that can be employed in this field. Areas covered: An overview of the design and employment of elastin-like polypeptides for cell encapsulation is given to outline the state of the art. Special attention is paid to the design of the macromolecule employed as well as to the method of matrix formation and the biological system involved. Expert opinion: As a result of recent progress in regenerative medicine there is a compelling need for materials that provide specific properties and demonstrate defined functional features. Rationally designed materials that may adapt according to applied external stimuli and that are responsive to biological systems, such as elastin-like polypeptides, belong to this class of smart material. A run through the components described to date represents a good starting point for further advancement in this area. Employment of these components in cell encapsulation application will promote its advance toward 'smart cell encapsulation technology'.

  11. Characterization of silicon micro-strip sensors with a pulsed infra-red laser system for the CBM experiment at FAIR

    Energy Technology Data Exchange (ETDEWEB)

    Ghosh, Pradeep [Goethe University, Frankfurt am Main (Germany); GSI Helmholtz Center for Heavy Ion Research GmbH, Darmstadt (Germany); Eschke, Juergen [GSI Helmholtz Center for Heavy Ion Research GmbH, Darmstadt (Germany); Facility for Anti-proton and Ion Research, GmbH, Darmstadt (Germany); Collaboration: CBM-Collaboration

    2015-07-01

    The Silicon Tracking System (STS) of the CBM experiment at FAIR is composed of 8 tracking stations comprising of 1292 double-sided silicon micro-strip sensors. A Laser Test System (LTS) has been developed for the quality assurance of prototype sensors. The aim is to scan sensors with a pulsed infra-red laser driven by step motor to determine the charge sharing in-between strips and to measure qualitative uniformity of the sensor response over the whole active area. Several prototype sensors with strip pitch of 50 and 58 μm have been tested, as well as a prototype module with realistic mechanical arrangement of sensor and read-out cables. The LTS is designed to measure sensor response in an automatized procedure across the sensor with focused laser beam (spot-size ∼ 12 μm, wavelength = 1060 nm). The pulse with duration (∼ 10 ns) and power (∼ 5 mW) of the laser pulses is selected such, that the absorption of the laser light in the 300 μm thick silicon sensors produces a number of about 24000 electrons, which is similar to the charge created by minimum ionizing particles (MIP) in these sensors. Results from laser scans of prototype sensors and detector module are reported.

  12. Analysis of n-in-p type silicon detectors for high radiation environment with fast analogue and binary readout systems

    Energy Technology Data Exchange (ETDEWEB)

    Printz, Martin

    2016-01-22

    The Large Hadron Collider at CERN is the most powerful particle accelerator ever built. The collision of high intensity proton beams at a center of mass energy of up to 14 TeV allows the exploration of the undiscovered territory at the TeV scale with great detail. The high energy physics frontier covers detailed Standard Model (SM) physics like the search for the SM Higgs boson which has been found in July 2012 but also physics beyond the SM like the Supersymmetry or studies of the quark-gluon plasma. The production rate of certain events is correlated to the instantaneous luminosity which is a measure for the number of detected events with in a certain time with respect to the interaction cross-section. In order to increase the statistics by collecting more data the integrated luminosity is maximized as far as possible. Simultaneously an increase of the particle energy and the luminosity reveals challenging experimental requirements for the trigger and detector systems present at the LHC. After a successful Run 1 of the machine between 2010 and 2013, the energy and the instantaneous luminosity of the machine are sequentially increased up to the last so called Phase II Upgrade planned for the years 2024 and 2025. The high luminosity LHC will provide particle beams with the final 14 TeV center of mass energy at an instantaneous luminosity of 5 x 10{sup 34} cm{sup -2}s{sup -1} which is five to seven times the nominal design luminosity. In the course of the Upgrade, the experiments will face extraordinary radiation environments and particle densities and have to be upgraded as well in order to cope with the challenging demands. The Compact Muon Solenoid (CMS) at CERN is a general purpose experiment with a diverse physics measurement program. It is built of several subdetectors. The most inner part consists of the pixel detector and the silicon strip tracker. The latter will be replaced completely during the Phase II Upgrade by a new layout whereas a different silicon

  13. A 500-MHz x-ray counting system with a silicon avalanche photodiode

    International Nuclear Information System (INIS)

    Kishimoto, Shunji

    2009-01-01

    In the present measurements using a Si-APD X-ray detector and a 500-MHz counting system, the maximum output rate of 3.3x10 8 s -1 was achieved for 8-keV X-rays in beamline BL-14A of the Photon Factory. A small Si-APD of 4-pF electric capacity was used as the detector device in order to output a pulse of a width shorter than 2 ns on the baseline. For processing the fast pulses, the discriminator and the scaler having a throughput of >500 MHz, were prepared. Since the acceleration frequency at the PF ring was 500.1 MHz and the empty-bunch spacing was 12/312 bunches per circumference, the expected maximum rate was 4.8x10 8s-1 according to the counting model for a pulsed photon source. The reason why the present system did not reach the expected value was the baseline shift at the amplifier outputs. The rise of +0.2 V was observed at a discriminator output of 3.3x10 8 s -1 , while the pulse height was lower than 0.2 V. The baseline shift was caused by an AC coupling circuit in the amplifier. If a DC coupling circuit can be used for the amplifier, instead of the AC coupling circuit, or an active adjustment to compensate the baseline shift is installed, the counting system will show an ideal response. Although the present system including NIM modules was not so compact, we would like to develop a new fast-counting circuit for a Si-APD array detector of more than 100 channels of small pixels, in near future. (author)

  14. Geochemistry of silicon isotopes

    Energy Technology Data Exchange (ETDEWEB)

    Ding, Tiping; Li, Yanhe; Gao, Jianfei; Hu, Bin [Chinese Academy of Geological Science, Beijing (China). Inst. of Mineral Resources; Jiang, Shaoyong [China Univ. of Geosciences, Wuhan (China).

    2018-04-01

    Silicon is one of the most abundant elements in the Earth and silicon isotope geochemistry is important in identifying the silicon source for various geological bodies and in studying the behavior of silicon in different geological processes. This book starts with an introduction on the development of silicon isotope geochemistry. Various analytical methods are described and compared with each other in detail. The mechanisms of silicon isotope fractionation are discussed, and silicon isotope distributions in various extraterrestrial and terrestrial reservoirs are updated. Besides, the applications of silicon isotopes in several important fields are presented.

  15. Liposomal nanoparticles encapsulating iloprost exhibit enhanced vasodilation in pulmonary arteries

    Directory of Open Access Journals (Sweden)

    Jain PP

    2014-07-01

    Full Text Available Pritesh P Jain,1 Regina Leber,1,2 Chandran Nagaraj,1 Gerd Leitinger,3 Bernhard Lehofer,4 Horst Olschewski,1,5 Andrea Olschewski,1,6 Ruth Prassl,1,4 Leigh M Marsh11Ludwig Boltzmann Institute for Lung Vascular Research, 2Biophysics Division, Institute of Molecular Biosciences, University of Graz, 3Research Unit Electron Microscopic Techniques, Institute of Cell Biology, Histology, and Embryology, 4Institute of Biophysics, 5Division of Pulmonology, Department of Internal Medicine, 6Department of Anesthesiology and Intensive Care Medicine, Medical University of Graz, Graz, AustriaAbstract: Prostacyclin analogues are standard therapeutic options for vasoconstrictive diseases, including pulmonary hypertension and Raynaud’s phenomenon. Although effective, these treatment strategies are expensive and have several side effects. To improve drug efficiency, we tested liposomal nanoparticles as carrier systems. In this study, we synthesized liposomal nanoparticles tailored for the prostacyclin analogue iloprost and evaluated their pharmacologic efficacy on mouse intrapulmonary arteries, using a wire myograph. The use of cationic lipids, stearylamine, or 1,2-di-(9Z-octadecenoyl-3-trimethylammonium-propane (DOTAP in liposomes promoted iloprost encapsulation to at least 50%. The addition of cholesterol modestly reduced iloprost encapsulation. The liposomal nanoparticle formulations were tested for toxicity and pharmacologic efficacy in vivo and ex vivo, respectively. The liposomes did not affect the viability of human pulmonary artery smooth muscle cells. Compared with an equivalent concentration of free iloprost, four out of the six polymer-coated liposomal formulations exhibited significantly enhanced vasodilation of mouse pulmonary arteries. Iloprost that was encapsulated in liposomes containing the polymer polyethylene glycol exhibited concentration-dependent relaxation of arteries. Strikingly, half the concentration of iloprost in liposomes elicited

  16. Encapsulation of curcumin in polyelectrolyte nanocapsules and their neuroprotective activity

    Science.gov (United States)

    Szczepanowicz, Krzysztof; Jantas, Danuta; Piotrowski, Marek; Staroń, Jakub; Leśkiewicz, Monika; Regulska, Magdalena; Lasoń, Władysław; Warszyński, Piotr

    2016-09-01

    Poor water solubility and low bioavailability of lipophilic drugs can be potentially improved with the use of delivery systems. In this study, encapsulation of nanoemulsion droplets was utilized to prepare curcumin nanocarriers. Nanosize droplets containing the drug were encapsulated in polyelectrolyte shells formed by the layer-by-layer (LbL) adsorption of biocompatible polyelectrolytes: poly-L-lysine (PLL) and poly-L-glutamic acid (PGA). The size of synthesized nanocapsules was around 100 nm. Their biocompatibility and neuroprotective effects were evaluated on the SH-SY5Y human neuroblastoma cell line using cell viability/toxicity assays (MTT reduction, LDH release). Statistically significant toxic effect was clearly observed for PLL coated nanocapsules (reduction in cell viability about 20%-60%), while nanocapsules with PLL/PGA coating did not evoke any detrimental effects on SH-SY5Y cells. Curcumin encapsulated in PLL/PGA showed similar neuroprotective activity against hydrogen peroxide (H2O2)-induced cell damage, as did 5 μM curcumin pre-dissolved in DMSO (about 16% of protection). Determination of concentration of curcumin in cell lysate confirmed that curcumin in nanocapsules has cell protective effect in lower concentrations (at least 20 times) than when given alone. Intracellular mechanisms of encapsulated curcumin-mediated protection engaged the prevention of the H2O2-induced decrease in mitochondrial membrane potential (MMP) but did not attenuate Reactive Oxygen Species (ROS) formation. The obtained results indicate the utility of PLL/PGA shell nanocapsules as a promising, alternative way of curcumin delivery for neuroprotective purposes with improved efficiency and reduced toxicity.

  17. Encapsulation layer design and scalability in encapsulated vertical 3D RRAM

    International Nuclear Information System (INIS)

    Yu, Muxi; Fang, Yichen; Wang, Zongwei; Chen, Gong; Pan, Yue; Yang, Xue; Yin, Minghui; Yang, Yuchao; Li, Ming; Cai, Yimao; Huang, Ru

    2016-01-01

    Here we propose a novel encapsulated vertical 3D RRAM structure with each resistive switching cell encapsulated by dielectric layers, contributing to both the reliability improvement of individual cells and thermal disturbance reduction of adjacent cells due to the effective suppression of unwanted oxygen vacancy diffusion. In contrast to the traditional vertical 3D RRAM, encapsulated bar-electrodes are adopted in the proposed structure substituting the previous plane-electrodes, thus encapsulated resistive switching cells can be naturally formed by simply oxidizing the tip of the metal bar-electrodes. In this work, TaO x -based 3D RRAM devices with SiO 2 and Si 3 N 4 as encapsulation layers are demonstrated, both showing significant advantages over traditional unencapsulated vertical 3D RRAM. Furthermore, it was found thermal conductivity and oxygen blocking ability are two key parameters of the encapsulation layer design influencing the scalability of vertical 3D RRAM. Experimental and simulation data show that oxygen blocking ability is more critical for encapsulation layers in the relatively large scale, while thermal conductivity becomes dominant as the stacking layers scale to the sub-10 nm regime. Finally, based on the notable impacts of the encapsulation layer on 3D RRAM scaling, an encapsulation material with both excellent oxygen blocking ability and high thermal conductivity such as AlN is suggested to be highly desirable to maximize the advantages of the proposed encapsulated structure. The findings in this work could pave the way for reliable ultrahigh-density storage applications in the big data era. (paper)

  18. The CMS silicon tracker

    International Nuclear Information System (INIS)

    D'Alessandro, R.; Biggeri, U.; Bruzzi, M.; Catacchini, E.; Civinini, C.; Focardi, E.; Lenzi, M.; Loreti, M.; Meschini, M.; Parrini, G.; Pieri, M.; Albergo, S.; Boemi, D.; Potenza, R.; Tricomi, A.; Angarano, M.; Creanza, D.; Palma, M. de; Fiore, L.; Maggi, G.; My, S.; Raso, G.; Selvaggi, G.; Tempesta, P.; Azzi, P.; Bacchetta, N.; Bisello, D.; Candelori, A.; Castro, A.; Da Rold, M.; Giraldo, A.; Martignon, G.; Paccagnella, A.; Stavitsky, I.; Babucci, E.; Bartalini, P.; Bilei, G.M.; Checcucci, B.; Ciampolini, P.; Lariccia, P.; Mantovani, G.; Passeri, D.; Santocchia, A.; Servoli, L.; Wang, Y.; Bagliesi, G.; Basti, A.; Bosi, F.; Borello, L.; Bozzi, C.; Castaldi, R.; Dell'Orso, R.; Giassi, A.; Messineo, A.; Palla, F.; Raffaelli, F.; Sguazzoni, G.; Starodumov, A.; Tonelli, G.; Vannini, C.; Verdini, P.G.; Xie, Z.; Breuker, H.; Caner, A.; Elliott-Peisert, A.; Feld, L.; Glessing, B.; Hammerstrom, R.; Huhtinen, M.; Mannelli, M.; Marchioro, A.; Schmitt, B.; Stefanini, G.; Connotte, J.; Gu, W.H.; Luebelsmeyer, K.; Pandoulas, D.; Siedling, R.; Wittmer, B.; Della Marina, R.; Freudenreich, K.; Lustermann, W.; Viertel, G.; Eklund, C.; Karimaeki, V.; Skog, K.; French, M.; Hall, G.; Mc Evoy, B.; Raymond, M.; Hrubec, J.; Krammer, M.; Piperov, S.; Tuuva, T.; Watts, S.; Silvestris, L.

    1998-01-01

    The new silicon tracker layout (V4) is presented. The system aspects of the construction are discussed together with the expected tracking performance. Because of the high radiation environment in which the detectors will operate, particular care has been devoted to the study of the characteristics of heavily irradiated detectors. This includes studies on performance (charge collection, cluster size, resolution, efficiency) as a function of the bias voltage, integrated fluence, incidence angle and temperature. (author)

  19. Silicon and Civilization,

    Science.gov (United States)

    1980-11-04

    of a diamond. 7. The particular physical and chemical properties of silicon resulted in the fact that in the periodic system it was found in the III...small quantities. Silica is found in blades of grass and grain, in reed and bamboo shoots, where it serves to stiffen the stalk. 2. Diatomite ... properties desired in technology. Quartz glass is very resistant to temperature change since it has a very small coefficient of thermal expansion, is

  20. Methods and systems for Raman and optical cross-interrogation in flow-through silicon membranes

    Science.gov (United States)

    Bond, Tiziana C.; Letant, Sonia E.

    2014-09-09

    Cross-interrogating photonic detection systems and methods are shown. A flow through photonic crystal membrane with a surface enhanced Raman scattering (SERS) substrate is provided with pores which are distributed along multiple regions. The pores of one region have walls to which a first type of target specific anchor can be attached, while pores of another region have walls to which a second type of target specific anchor can be attached. An optical arrangement out-of-plane to the SERS substrate is also provided for enhanced sensitivity and identification of target organisms.