Microparticle injection effects on microwave transmission through an overly dense plasma layer

Energy Technology Data Exchange (ETDEWEB)

Gillman, Eric D., E-mail: eric.gillman@nrl.navy.mil; Amatucci, W. E. [Naval Research Laboratory, Washington, DC 20375 (United States); Williams, Jeremiah [Wittenberg University, Springfield, Ohio 45501 (United States); Compton, C. S. [Sotera Defense Solutions, Herndon, Virginia 20171 (United States)

2015-04-15

Microparticles injected into a plasma have been shown to deplete the free electron population as electrons are collected through the process of microparticles charging to the plasma floating potential. However, these charged microparticles can also act to scatter electromagnetic signals. These experiments investigate microwave penetration through a previously impenetrable overly dense plasma layer as microparticles are injected and the physical phenomena associated with the competing processes that occur due to electron depletion and microwave scattering. The timescales for when each of these competing processes dominates is analyzed in detail. It was found that while both processes play a significant and dominant role at different times, ultimately, transmission through this impenetrable plasma layer can be significantly increased with microparticle injection.

Tunneling spin injection into single layer graphene.

Science.gov (United States)

Han, Wei; Pi, K; McCreary, K M; Li, Yan; Wong, Jared J I; Swartz, A G; Kawakami, R K

2010-10-15

We achieve tunneling spin injection from Co into single layer graphene (SLG) using TiO₂ seeded MgO barriers. A nonlocal magnetoresistance (ΔR(NL)) of 130  Ω is observed at room temperature, which is the largest value observed in any material. Investigating ΔR(NL) vs SLG conductivity from the transparent to the tunneling contact regimes demonstrates the contrasting behaviors predicted by the drift-diffusion theory of spin transport. Furthermore, tunnel barriers reduce the contact-induced spin relaxation and are therefore important for future investigations of spin relaxation in graphene.

Wear resistance of WCp/Duplex Stainless Steel metal matrix composite layers prepared by laser melt injection

NARCIS (Netherlands)

Do Nascimento, A. M.; Ocelik, V.; Ierardi, M. C. F.; De Hosson, J. Th. M.

2008-01-01

Laser Melt Injection (LMI) was used to prepare metal matrix composite layers with a thickness of about 0.7 mm and approximately 10% volume fraction of WC particles in three kinds of Cast Duplex Stainless Steels (CDSSs). WC particles were injected into the molten surface layer using Nd:YAG high power

A layer-by-layer ZnO nanoparticle-PbS quantum dot self-assembly platform for ultrafast interfacial electron injection

KAUST Repository

Eita, Mohamed Samir

2014-08-28

Absorbent layers of semiconductor quantum dots (QDs) are now used as material platforms for low-cost, high-performance solar cells. The semiconductor metal oxide nanoparticles as an acceptor layer have become an integral part of the next generation solar cell. To achieve sufficient electron transfer and subsequently high conversion efficiency in these solar cells, however, energy-level alignment and interfacial contact between the donor and the acceptor units are needed. Here, the layer-by-layer (LbL) technique is used to assemble ZnO nanoparticles (NPs), providing adequate PbS QD uptake to achieve greater interfacial contact compared with traditional sputtering methods. Electron injection at the PbS QD and ZnO NP interface is investigated using broadband transient absorption spectroscopy with 120 femtosecond temporal resolution. The results indicate that electron injection from photoexcited PbS QDs to ZnO NPs occurs on a time scale of a few hundred femtoseconds. This observation is supported by the interfacial electronic-energy alignment between the donor and acceptor moieties. Finally, due to the combination of large interfacial contact and ultrafast electron injection, this proposed platform of assembled thin films holds promise for a variety of solar cell architectures and other settings that principally rely on interfacial contact, such as photocatalysis. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Electrically conductive polyaniline as hole-injection layer for MEH-PPV:BT based polymer light emitting diodes

International Nuclear Information System (INIS)

Mohsennia, M.; Bidgoli, M. Massah; Boroumand, F. Akbari; Nia, A. Mohsen

2015-01-01

Graphical abstract: The PANI prepared at 15 °C with higher electrical conductivity has been used as hole-injection layer (HIL) in polymer light emitting diodes (PLEDs) with structure of ITO/PANI/MEHPPV:BT/Al. - Highlights: • Polyaniline (PANI) was synthesized at different temperatures (5, 10, 15, 20 and 25 °C). • The PANI sample with higher electrical conductivity was used as HIL in the PLED devices. • The PANI injection layer yielded higher current and lower turn-on voltage. • The effect of MEH-PPV:BT weight ratio on the PLED performance has been also investigated. • The J–V characteristics of the devices have been explained by FN tunneling model. - Abstract: Polyaniline (PANI) was synthesized by oxidative polymerization of aniline at different temperatures (5, 10, 15, 20 and 25 °C). The influence of polymerization temperature on sheet resistance of PANI was investigated, and the one prepared at 15 °C which showed lowest resistivity was chosen for further analysis. PANI was subsequently used as hole-injection layer (HIL) in polymer light emitting diodes (PLEDs) with structure of poly(ethylene terephthalate) (PET)/indium tin oxide (ITO)/PANI/MEH-PPV:BT/aluminum (Al). The PLEDs with emission layer made from a blend of poly [2-methoxy-5-(2′-ethyl-hexyloxy)-1,4-phenylene vinylene] (MEH-PPV) and an electron transporting material, benzothiadiazole (BT), were fabricated at room conditions without using glove boxes. Our results showed an improvement in performance of our PANI-based fabricated PLEDs (PET/ITO/PANI/MEH-PPV:BT/Al) compared to the conventional devices that use poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PET/ITO/PEDOT:PSS/MEH-PPV:BT/Al) as their HIL. The hole injection barrier height (φ) of the fabricated PLEDs were then estimated using the Fowler–Nordheim (FN) field-emission tunneling theory and revealed that the barrier height decreases by increasing the BT concentration in the MEH-PPV:BT blend layer

Organic light-emitting diodes with F16CuPC as an efficient hole-injection layer

International Nuclear Information System (INIS)

Lee, H. K.; Shin, Y. C.; Kwon, D. S.; Lee, C. H.

2006-01-01

We report a new hole-injection material, copper hexadecafluorophthalocyanine (F 16 CuPC) for organic light-emitting diodes (OLEDs) consisting of N,N'-di(1-naphthyl)-N,N'-diphenylbenzidine (α-NPD) as a hole-transport layer and 8-tris-hydroxyquinoline aluminum (Alq 3 ) as a light-emitting and electron-transport layer. The insertion of the F 16 CuPC between indium-tin oxide (ITO) and α-NPD reduces the operating voltage significantly and thereby increases the luminous efficiency. By measuring the device characteristics for various F 16 CuPC thicknesses, we find that an optimum F 16 CuPC thickness is about 15 nm. At a luminance of 1000 cd/m 2 , the device with 15-nm-thick F 16 CuPC shows a luminous efficiency of 1.5 lm/W and a device operating voltage of 7.2 V while the device without the F 16 CuPC layer shows 1.1 lm/W and 10.4 V. The significant decrease in a driving voltage and increase in the luminous efficiency can be attributed to the high hole-injection efficiency when F 16 CuPC is inserted between ITO and α-NPD.

Performance Enhancement of Organic Light-Emitting Diodes Using Electron-Injection Materials of Metal Carbonates

Science.gov (United States)

Shin, Jong-Yeol; Kim, Tae Wan; Kim, Gwi-Yeol; Lee, Su-Min; Shrestha, Bhanu; Hong, Jin-Woong

2016-05-01

Performance of organic light-emitting diodes was investigated depending on the electron-injection materials of metal carbonates (Li2CO3 and Cs2CO3 ); and number of layers. In order to improve the device efficiency, two types of devices were manufactured by using the hole-injection material (Teflon-amorphous fluoropolymer -AF) and electron-injection materials; one is a two-layer reference device ( ITO/Teflon-AF/Alq3/Al ) and the other is a three-layer device (ITO/Teflon-AF/Alq3/metal carbonate/Al). From the results of the efficiency for the devices with hole-injection layer and electron-injection layer, it was found that the electron-injection layer affects the electrical properties of the device more than the hole-injection layer. The external-quantum efficiency for the three-layer device with Li2CO3 and Cs2CO3 layer is improved by approximately six and eight times, respectively, compared with that of the two-layer reference device. It is thought that a use of electron-injection layer increases recombination rate of charge carriers by the active injection of electrons and the blocking of holes.

Bubble-induced mixing of two horizontal liquid layers with non-uniform gas injection at the bottom

International Nuclear Information System (INIS)

Cheung, F.B.; Pedersen, D.R.; Leinweber, G.

1986-01-01

During a postulated severe core meltdown accident in an LMFBR, a large amount of sodium coolant may spill into the reactor concrete cavity. A layer of liquid products may form as a result of the sodium-concrete reactions. The liquid product layer, which is highly viscous and much heavier than sodium, separates the concrete from the sodium pool. In general, the downward transport of sodium through the liquid product layer to the unreacted concrete surface, which controls the rate of chemical erosion of the concrete, depends strongly on the agitation induced by gas evolution from the heated concrete. In this study, experiments were conducted to explore the effect of non-uniform gas injection on mixing of two horizontal mutually soluble liquid layers. The liquid in the lower layer was chosen to be more viscous and heavier than the liquid in the upper layer. To simulate the reactor accident situation, gas was injected at the bottom of the liquid-liquid system through a circular hole that covered only the center portion of the bottom surface of the lower liquid layer. The bubble-induced mixing motions were observed and the rate of mixing was measured for different hole sizes and various gas flow rates. The results of this study clearly show that the rate of gas injection is not the only parameter controlling the mixing of the liquid-liquid system. The effect of non-uniform gas injection is important at high gas flow rates. Within the present experimental conditions, the reduction in the overall mixing rate can be as large as a factor of three

Low absorption loss p-AlGaN superlattice cladding layer for current-injection deep ultraviolet laser diodes

International Nuclear Information System (INIS)

Martens, M.; Kuhn, C.; Ziffer, E.; Simoneit, T.; Rass, J.; Wernicke, T.; Kueller, V.; Knauer, A.; Einfeldt, S.; Weyers, M.; Kneissl, M.

2016-01-01

Current injection into AlGaN-based laser diode structures with high aluminum mole fractions for deep ultraviolet emission is investigated. The electrical characteristics of laser diode structures with different p-AlGaN short period superlattice (SPSL) cladding layers with various aluminum mole fractions are compared. The heterostructures contain all elements that are needed for a current-injection laser diode including cladding and waveguide layers as well as an AlGaN quantum well active region emitting near 270 nm. We found that with increasing aluminum content in the p-AlGaN cladding, the diode turn-on voltage increases, while the series resistance slightly decreases. By introducing an SPSL instead of bulk layers, the operating voltage is significantly reduced. A gain guided broad area laser diode structure with transparent p-Al_0_._7_0Ga_0_._3_0N waveguide layers and a transparent p-cladding with an average aluminum content of 81% was designed for strong confinement of the transverse optical mode and low optical losses. Using an optimized SPSL, this diode could sustain current densities of more than 4.5 kA/cm"2.

Steam and air co-injection in removing residual TCE in unsaturated layered sandy porous media.

Science.gov (United States)

Peng, Sheng; Wang, Ning; Chen, Jiajun

2013-10-01

Steam and air co-injection is a promising technique for volatile and semi-volatile organic contaminant remediation in heterogeneous porous media. In this study, removal of trichloroethene (TCE) with steam-air co-injection was investigated through a series of 2D sandbox experiments with different layered sand structures, and through numerical simulations. The results show that a layered structure with coarse sand, in which steam and air convection are relatively rapid, resulted in a higher removal rate and a larger removal ratio than those observed in an experiment using finer sand; however, the difference was not significant, and the removal ratios from three experiments ranged from 85% to 94%. Slight downward movement of TCE was observed for Experiment 1 (TCE initially in a fine sand zone encased in a coarse sand), while no such movement was observed for Experiment 2 (TCE initially in two fine sand layers encased in a coarse sand) or 3 (TCE initially in a silty sand zone encased in a coarse sand). Simulations show accumulation of TCE at the interface of the layered sands, which indicates a capillary barrier effect in restraining the downward movement of TCE. This effect is illustrated further by a numerical experiment with homogeneous coarse sand, in which continuous downward TCE movement to the bottom of the sandbox was simulated. Another numerical experiment with higher water saturation was also conducted. The results illustrate a complicated influence of water saturation on TCE removal in a layered sand structure. Published by Elsevier B.V.

Investigation of organic light-emitting diodes with novel organic electron injection layers

Energy Technology Data Exchange (ETDEWEB)

Lee, Sunae; Sethuraman, Kunjithapatham; An, Jongdeok; Im, Chan [Konkuk University, Seoul (Korea, Republic of); Hwang, Boseon [Jinwoong Industrial Co. Ltd., Seoul (Korea, Republic of)

2012-03-15

1-(diphenyl-phosphinoyl)-4-(2,2-diphenyl-vinyl)-benzene (DpDvB) and 4-(diphenyl-phosphinoyl)-4'-(2,2-diphenyl-vinyl)-biphenyl (DpDvBp) have been prepared and used as efficient electron injection layers (EILs) between aluminum cathode and tris (8-hydroxyquinoline) aluminum organic light emitting diodes (OLED). The performances of devices with different thicknesses of DpDvB and DpDvBp were investigated. Experimental results show that the turn-on voltage of the devices was decreased and the luminance of the devices was enhanced with increasing thickness of the EILs. Power efficiencies of 1.07 lm/W and 0.97 lm/W were obtained by inserting a 3-nm-thick EIL of DpDvB and a 5 nm thick EIL of DpDvBp, respectively. These efficiencies are comparable to that of the device using LiF as an EIL. The results prove that DpDvB and DpDvBp layers are also suitable for efficient EILs in OLEDs.

Calculation of eddy viscosity in a compressible turbulent boundary layer with mass injection and chemical reaction, volume 1. [theoretical analysis

Science.gov (United States)

Omori, S.

1973-01-01

The turbulent kinetic energy equation is coupled with boundary layer equations to solve the characteristics of compressible turbulent boundary layers with mass injection and combustion. The Reynolds stress is related to the turbulent kinetic energy using the Prandtl-Wieghardt formulation. When a lean mixture of hydrogen and nitrogen is injected through a porous plate into the subsonic turbulent boundary layer of air flow and ignited by external means, the turbulent kinetic energy increases twice as much as that of noncombusting flow with the same mass injection rate of nitrogen. The magnitudes of eddy viscosity between combusting and noncombusting flows with injection, however, are almost the same due to temperature effects, while the distributions are different. The velocity profiles are significantly affected by combustion; that is, combustion alters the velocity profile as if the mass injection rate is increased, reducing the skin-friction as a result of a smaller velocity gradient at the wall. If pure hydrogen as a transpiration coolant is injected into a rocket nozzle boundary layer flow of combustion products, the temperature drops significantly across the boundary layer due to the high heat capacity of hydrogen. At a certain distance from the wall, hydrogen reacts with the combustion products, liberating an extensive amount of heat. The resulting large increase in temperature reduces the eddy viscosity in this region.

Device characteristics of organic light-emitting diodes based on electronic structure of the Ba-doped Alq3 layer.

Science.gov (United States)

Lim, Jong Tae; Kim, Kyung Nam; Yeom, Geun Young

2009-12-01

Organic light-emitting diodes (OLEDs) with a Ba-doped tris(8-quinolinolato)aluminum(III) (Alq3) layer were fabricated to reduce the barrier height for electron injection and to improve the electron conductivity. In the OLED consisting of glass/ITO/4,4',4"-tris[2-naphthylphenyl-1-phenylamino]triphenylamine (2-TNATA, 30 nm)/4,4'-bis[N-(1-napthyl)-N-phenyl-amino]-biphenyl (NPB, 18 nm)/Alq3 (42 nm)/Ba-doped Alq3 (20 nm, x%: x = 0, 10, 25, and 50)/Al (100 nm), the device with the Alq3 layer doped with 10% Ba showed the highest light out-coupling characteristic. However, as the Ba dopant concentration was increased from 25% to 50%, this device characteristic was largely reduced. The characteristics of these devices were interpreted on the basis of the chemical reaction between Ba and Alq3 and the electron injection property by analyzing the electronic structure of the Ba-doped Alq3 layer. At a low Ba doping of 10%, mainly the Alq3 radical anion species was formed. In addition, the barrier height for electron injection in this layer was decreased to 0.6 eV, when compared to the pristine Alq3 layer. At a high Ba doping of 50%, the Alq3 molecules were severely decomposed. When the Ba dopant concentration was changed, the light-emitting characteristics of the devices were well coincided with the formation mechanism of Alq3 radical anion and Alq3 decomposition species.

Reduction of birefringence in a skin-layer of injection molded polymer strips using CO{sub 2} laser irradiation

Energy Technology Data Exchange (ETDEWEB)

Kurosaki, Yasuo; Satoh, Isao; Saito, Takushi [Tokyo Inst. of Tech. (Japan). Dept. of Mechanical Intelligent Systems Engineering

1995-12-31

Injection molding of polymers is currently utilized for numerous industrial applications. Because of high productivity and stable quality of molded products, the injection-molding process makes the production costs lower, and therefore, is expected to spread more widely in the future. This paper deals with a technique for improving the optical quality of injection molded polymer products using radiative heating. The birefringence frozen in a skin-layer of the molded part was reduced by CO{sub 2} laser heating, and the efficiency of this technique was investigated experimentally. Namely, a simple numerical calculation was performed to estimate the heating efficiency of CO{sub 2} laser in the polymer, effects of radiation heating on the skin-layer of the molded polymer were observed by using a mold with transparent windows, and the residual birefringence frozen in the final molded specimen was measured. The results clearly showed that the birefringence in the skin-layer of injection molded polymer strips was reduced with CO{sub 2} laser heating. The authors believe that the proposed method for reducing the birefringence frozen in injection-molded polymer products is suitable for practical molding, because process time required for the injection-molding is only slightly increased with this method.

The concept of "compartment allergy": prilocaine injected into different skin layers

Directory of Open Access Journals (Sweden)

Wobser Marion

2011-04-01

Full Text Available Abstract We herein present a patient with delayed-type allergic hypersensitivity against prilocaine leading to spreading eczematous dermatitis after subcutaneous injections for local anesthesia with prilocaine. Prilocaine allergy was proven by positive skin testing and subcutaneous provocation, whereas the evaluation of other local anesthetics - among them lidocaine, articaine and mepivacaine - did not exhibit any evidence for cross-reactivity. Interestingly, our patient repeatedly tolerated strictly deep subcutaneous injection of prilocaine in provocation testing while patch and superficial subcutaneous application mounted strong allergic responses. We hypothesize, that lower DC density in deeper cutaneous compartments and/or different DC subsets exhibiting distinct functional immunomodulatory properties in the various layers of the skin may confer to the observed absence of clinical reactivity against prilocaine after deep subcutaneous injection. The term compartment allergy indicates that the route of allergen administration together with the targeted immunologic environment orchestrates on the immunologic outcome: overt T-cell mediated allergy or clinical tolerance.

Bubble-induced mixing of two horizontal liquid layers with non-uniform gas injection at the bottom

International Nuclear Information System (INIS)

Cheung, F.B.; Leinweber, G.; Pedersen, D.R.

1984-01-01

During a postulated severe core meltdown accident in an LMFBR, a large amount of sodium coolant may spill into the reactor concrete cavity. A layer of liquid products may form as a result of the sodium-concrete reactions. The liquid product layer, which is highly viscous and much heavier than sodium, separates the concrete from the sodium pool. In general, the downward transport of sodium through the liquid product layer to the unreacted concrete surface, which controls the rate of chemical erosion of the concrete, depends strongly on the agitation induced by gas evolution from the heated concrete. In this study, experiments were conducted to explore the effect of non-uniform gas injection on mixing of two horizontal mutually soluble liquid layers. The liquid in the lower layer was chosen to be more viscous and heavier than the liquid in the upper layer. To simulate the reactor accident situation, gas was injected at the bottom of the liquid-liquid system through a circular hole that covered only the center portion of the bottom surface of the lower liquid layer. The bubble-induced mixing motions were observed and the rate of mixing was measured for different hole sizes and for various gas flow rates

Conduction mechanisms in thin atomic layer deposited Al2O3 layers

International Nuclear Information System (INIS)

Spahr, Holger; Montzka, Sebastian; Reinker, Johannes; Hirschberg, Felix; Kowalsky, Wolfgang; Johannes, Hans-Hermann

2013-01-01

Thin Al 2 O 3 layers of 2–135 nm thickness deposited by thermal atomic layer deposition at 80 °C were characterized regarding the current limiting mechanisms by increasing voltage ramp stress. By analyzing the j(U)-characteristics regarding ohmic injection, space charge limited current (SCLC), Schottky-emission, Fowler-Nordheim-tunneling, and Poole-Frenkel-emission, the limiting mechanisms were identified. This was performed by rearranging and plotting the data in a linear scale, such as Schottky-plot, Poole-Frenkel-plot, and Fowler-Nordheim-plot. Linear regression then was applied to the data to extract the values of relative permittivity from Schottky-plot slope and Poole-Frenkel-plot slope. From Fowler-Nordheim-plot slope, the Fowler-Nordheim-energy-barrier was extracted. Example measurements in addition to a statistical overview of the results of all investigated samples are provided. Linear regression was applied to the region of the data that matches the realistic values most. It is concluded that ohmic injection and therefore SCLC only occurs at thicknesses below 12 nm and that the Poole-Frenkel-effect is no significant current limiting process. The extracted Fowler-Nordheim-barriers vary in the range of up to approximately 4 eV but do not show a specific trend. It is discussed whether the negative slope in the Fowler-Nordheim-plot could in some cases be a misinterpreted trap filled limit in the case of space charge limited current

A novel injectable thermoresponsive and cytocompatible gel of poly(N-isopropylacrylamide) with layered double hydroxides facilitates siRNA delivery into chondrocytes in 3D culture

NARCIS (Netherlands)

Yang, H.Y.; Ee, R.J. van; Timmer, K.; Craenmehr, E.G.M.; Huang, J.H.; Öner, C.; Dhert, W.J.A.; Kragten, A.H.M.; Willems, N.; Grinwis, G.C.M.; Tryfonidou, M.A.; Papen-Botterhuis, N.E.; Creemers, L.B.

2015-01-01

Hybrid hydrogels composed of poly(N-isopropylacrylamide) (pNIPAAM) and layered double hydroxides (LDHs) are presented in this study as novel injectable and thermoresponsive materials for siRNA delivery, which could specifically target several negative regulators of tissue homeostasis in

A novel injectable thermoresponsive and cytocompatible gel of poly(N-isopropylacrylamide) with layered double hydroxides facilitates siRNA delivery into chondrocytes in 3D culture

NARCIS (Netherlands)

Yang, Hsiao-yin; van Ee, Renz J; Timmer, Klaas; Craenmehr, Eric G M; Huang, Julie H; Oner, F. Cumhur; Dhert, Wouter J A; Kragten, Angela H M; Willems, Nicole; Grinwis, Guy C M; Tryfonidou, Marianna A; Papen-Botterhuis, Nicole E; Creemers, Laura B

Hybrid hydrogels composed of poly(N-isopropylacrylamide) (pNIPAAM) and layered double hydroxides (LDHs) are presented in this study as novel injectable and thermoresponsive materials for siRNA delivery, which could specifically target several negative regulators of tissue homeostasis in

Defect Generation for a Hydrated Layer and Thermal Stability Based on Ba0.7Sr0.3TiO3/SiO2 as H+ Sensitive Layer in Ion-Sensitive Field-Effect Transistor Devices

Science.gov (United States)

Chen, Chun-Yuan; Chou, Jung-Chuan; Chou, Hsueh-Tao

2009-04-01

In this paper, we present a novel sensitive ion-sensitive field-effect transistor (ISFET) membrane based on Ba0.7Sr0.3TiO3 (BST)/SiO2 fabricated by sputtering deposition. The proposed device exhibits a linear shift in acidic solutions in the pH range from 1 to 10. The device sensitivity was about 50-55 mV/pH for different deposition times. We also examined the trapping behavior of the surface hydrated layer using the metal-insulator-semiconductor (MIS) structure. Results show that the hydration layer gives rise to stress polarity dependence of electron injection when immersed in pH buffer solutions. Injection from the gate electrode produces larger positive charges and interface state densities in contrast to the substrate injection, which causes simultaneous positive and negative charge trapping. A physical model that quantitatively describes the asymmetry associated with the hydrated diffusion layer is presented, and the temperature effects of BST/SiO2 ISFET devices in the range from 25 to 65 °C were examined. We observed that pH sensitivity increases with increasing temperature. The temperature coefficient of sensitivity (TCS) can be divided into two different ranges: 0.08 mV/pH °C between 25 and 45 °C, and 0.57 mV/pH °C between 45 and 65 °C. A better thermal stability is produced in the 25 and 45 °C range in comparison with other sensitive layers.

Wastewater injection and slip triggering: Results from a 3D coupled reservoir/rate-and-state model

Science.gov (United States)

Babazadeh, M.; Olson, J. E.; Schultz, R.

2017-12-01

Seismicity induced by fluid injection is controlled by parameters related to injection conditions, reservoir properties, and fault frictional behavior. We present results from a combined model that brings together injection physics, reservoir dynamics, and fault physics to better explain the primary controls on induced seismicity. We created a 3D fluid flow simulator using the embedded discrete fracture technique and then coupled it with a 3D displacement discontinuity model that uses rate and state friction to model slip events. The model is composed of three layers, including the top-seal, the injection reservoir, and the basement. Permeability is anisotropic (vertical vs horizontal) and along with porosity varies by layer. Injection control can be either rate or pressure. Fault properties include size, 2D permeability, and frictional properties. Several suites of simulations were run to evaluate the relative importance of each of the factors from all three parameter groups. We find that the injection parameters interact with the reservoir parameters in the context of the fault physics and these relations change for different reservoir and fault characteristics, leading to the need to examine the injection parameters only within the context of a particular faulted reservoir. For a reservoir with no flow boundaries, low permeability (5 md), and a fault with high fault-parallel permeability and critical stress, injection rate exerts the strongest control on magnitude and frequency of earthquakes. However, for a higher permeability reservoir (80 md), injection volume becomes the more important factor. Fault permeability structure is a key factor in inducing earthquakes in basement rocks below the injection reservoir. The initial failure state of the fault, which is challenging to assess, can have a big effect on the size and timing of events. For a fault 2 MPa below critical state, we were able to induce a slip event, but it occurred late in the injection history

Subnanometer Ga2O3 tunnelling layer by atomic layer deposition to achieve 1.1 V open-circuit potential in dye-sensitized solar cells.

Science.gov (United States)

Chandiran, Aravind Kumar; Tetreault, Nicolas; Humphry-Baker, Robin; Kessler, Florian; Baranoff, Etienne; Yi, Chenyi; Nazeeruddin, Mohammad Khaja; Grätzel, Michael

2012-08-08

Herein, we present the first use of a gallium oxide tunnelling layer to significantly reduce electron recombination in dye-sensitized solar cells (DSC). The subnanometer coating is achieved using atomic layer deposition (ALD) and leading to a new DSC record open-circuit potential of 1.1 V with state-of-the-art organic D-π-A sensitizer and cobalt redox mediator. After ALD of only a few angstroms of Ga(2)O(3), the electron back reaction is reduced by more than an order of magnitude, while charge collection efficiency and fill factor are increased by 30% and 15%, respectively. The photogenerated exciton separation processes of electron injection into the TiO(2) conduction band and the hole injection into the electrolyte are characterized in detail.

Solution-processed high-LUMO-level polymers in n-type organic field-effect transistors: a comparative study as a semiconducting layer, dielectric layer, or charge injection layer

International Nuclear Information System (INIS)

Liu, Chuan; Xu, Yong; Liu, Xuying; Minari, Takeo; Sirringhaus, Henning; Noh, Yong-Young

2015-01-01

In solution-processed organic field-effect transistors (OFETs), the polymers with high level of lowest unoccupied molecular orbitals (LUMOs, > −3.5 eV) are especially susceptible to electron-trapping that causes low electron mobility and strong instability in successive operation. However, the role of high-LUMO-level polymers could be different depending on their locations relative to the semiconductor/insulator interface, or could even possibly benefit the device in some cases. We constructed unconventional polymer heterojunction n-type OFETs to control the location of the same polymer with a high LUMO level, to be in, under, or above the accumulation channel. We found that although the devices with the polymer in the channel suffer from dramatic instability, the same polymer causes much less instability when it acts as a dielectric modification layer or charge injection layer. Especially, it may even improve the device performance in the latter case. This result helps to improve our understanding of the electron-trapping and explore the value of these polymers in OFETs. (invited article)

Silver nanoparticles as a key feature of a plasma polymer composite layer in mitigation of charge injection into polyethylene under dc stress

International Nuclear Information System (INIS)

Milliere, L; Makasheva, K; Laurent, C; Despax, B; Boudou, L; Teyssedre, G

2016-01-01

The aim of this work is to limit charge injection from a semi-conducting electrode into low density polyethylene (LDPE) under dc field by tailoring the polymer surface using a silver nanoparticles-containing layer. The layer is composed of a plane of silver nanoparticles embedded in a semi-insulating organosilicon matrix deposited on the polyethylene surface by a plasma process. Size, density and surface coverage of the nanoparticles are controlled through the plasma process. Space charge distribution in 300 μm thick LDPE samples is measured by the pulsed-electroacoustic technique following a short term (step-wise voltage increase up to 50 kV mm −1 , 20 min in duration each, followed by a polarity inversion) and a longer term (up to 12 h under 40 kV mm −1 ) protocols for voltage application. A comparative study of space charge distribution between a reference polyethylene sample and the tailored samples is presented. It is shown that the barrier effect depends on the size distribution and the surface area covered by the nanoparticles: 15 nm (average size) silver nanoparticles with a high surface density but still not percolating form an efficient barrier layer that suppress charge injection. It is worthy to note that charge injection is detected for samples tailored with (i) percolating nanoparticles embedded in organosilicon layer; (ii) with organosilicon layer only, without nanoparticles and (iii) with smaller size silver particles (<10 nm) embedded in organosilicon layer. The amount of injected charges in the tailored samples increases gradually in the samples ranking given above. The mechanism of charge injection mitigation is discussed on the basis of complementary experiments carried out on the nanocomposite layer such as surface potential measurements. The ability of silver clusters to stabilize electrical charges close to the electrode thereby counterbalancing the applied field appears to be a key factor in explaining the charge injection

Co3O4 protective coatings prepared by Pulsed Injection Metal Organic Chemical Vapour Deposition

DEFF Research Database (Denmark)

Burriel, M.; Garcia, G.; Santiso, J.

2005-01-01

of deposition temperature. Pure Co3O4 spinel structure was found for deposition temperatures ranging from 360 to 540 degreesC. The optimum experimental parameters to prepare dense layers with a high growth rate were determined and used to prepare corrosion protective coatings for Fe-22Cr metallic interconnects......Cobalt oxide films were grown by Pulsed Injection Metal Organic Chemical Vapour Deposition (PI-MOCVD) using Co(acac)(3) (acac=acetylacetonate) precursor dissolved in toluene. The structure, morphology and growth rate of the layers deposited on silicon substrates were studied as a function......, to be used in Intermediate Temperature Solid Oxide Fuel Cells. (C) 2004 Elsevier B.V. All rights reserved....

Enhancement of hole-injection and power efficiency of organic light emitting devices using an ultra-thin ZnO buffer layer

International Nuclear Information System (INIS)

Huang, H.-H.; Chu, S.-Y.; Kao, P.-C.; Chen, Y.-C.; Yang, M.-R.; Tseng, Z.-L.

2009-01-01

The advantages of using an anode buffer layer of ZnO on the electro-optical properties of organic light emitting devices (OLEDs) are reported. ZnO powders were thermal-evaporated and then treated with ultra-violet (UV) ozone exposure to make the ZnO layers. The turn-on voltage of OLEDs decreased from 4 V (4.2 cd/m 2 ) to 3 V (3.4 cd/m 2 ) and the power efficiency increased from 2.7 lm/W to 4.7 lm/W when a 1-nm-thick ZnO layer was inserted between indium tin oxide (ITO) anodes and α-naphthylphenylbiphenyl diamine (NPB) hole-transporting layers. X-ray and ultra-violet photoelectron spectroscopy (XPS and UPS) results revealed the formation of the ZnO layer and showed that the work function increased by 0.59 eV when the ZnO/ITO layer was treated by UV-ozone for 20 min. The surface of the ZnO/ITO film became smoother than that of bare ITO film after the UV-ozone treatment. Thus, the hole-injection energy barrier was lowered by inserting an ZnO buffer layer, resulting in a decrease of the turn-on voltage and an increase of the power efficiency of OLEDs.

Viscous-shock-layer solutions with coupled radiation and ablation injection for earth entry

Science.gov (United States)

Gupta, Roop N.; Lee, Kam-Pui; Moos, James N.; Sutton, Kenneth

1990-01-01

Results are obtained for the forebody of a planetary exploration vehicle entering the earth's atmosphere. A viscous-shock-layer analysis is used assuming the flow to be laminar and in chemical equilibrium. Presented results include coupled radiation and ablation injection. This study further includes the effect of different transport and thermodynamic properties and radiation models. A Lewis number of 1.4 appears adequate for the radiation-dominated flows. Five velocities corresponding to different possible trajectory points at an altitude of 70 km have been further analyzed in detail. Sublimation and radiative equilibrium wall temperatures are employed for cases with and without coupled injection, respectively. For the cases analyzed here, the mass injection rates are small. However, the rates could become large if a lower altitude is used for aerobraking and/or the body size is increased. A comparison of the equilibrium results with finite-rate chemistry calculation shows the flowfield to be in chemical equilibrium.

Enhancing carrier injection in the active region of a 280nm emission wavelength LED using graded hole and electron blocking layers

KAUST Repository

Janjua, Bilal; Ng, Tien Khee; Alyamani, Ahmed Y.; El-Desouki, Munir M.; Ooi, Boon S.

2014-01-01

A theoretical investigation of AlGaN UV-LED with band engineering of hole and electron blocking layers (HBL and EBL, respectively) was conducted with an aim to improve injection efficiency and reduce efficiency droop in the UV LEDs. The analysis is based on energy band diagrams, carrier distribution and recombination rates (Shockley-Reed-Hall, Auger, and radiative recombination rates) in the quantum well, under equilibrium and forward bias conditions. Electron blocking layer is based on AlaGa1-aN / Al b → cGa1-b → 1-cN / AldGa 1-dN, where a < d < b < c. A graded layer sandwiched between large bandgap AlGaN materials was found to be effective in simultaneously blocking electrons and providing polarization field enhanced carrier injection. The graded interlayer reduces polarization induced band bending and mitigates the related drawback of impediment of holes injection. Similarly on the n-side, the Alx → yGa1-x → 1-yN / AlzGa 1-zN (x < z < y) barrier acts as a hole blocking layer. The reduced carrier leakage and enhanced carrier density in the active region results in significant improvement in radiative recombination rate compared to a structure with the conventional rectangular EBL layers. The improvement in device performance comes from meticulously designing the hole and electron blocking layers to increase carrier injection efficiency. The quantum well based UV-LED was designed to emit at 280nm, which is an effective wavelength for water disinfection application.

Enhancing carrier injection in the active region of a 280nm emission wavelength LED using graded hole and electron blocking layers

KAUST Repository

Janjua, Bilal

2014-02-27

A theoretical investigation of AlGaN UV-LED with band engineering of hole and electron blocking layers (HBL and EBL, respectively) was conducted with an aim to improve injection efficiency and reduce efficiency droop in the UV LEDs. The analysis is based on energy band diagrams, carrier distribution and recombination rates (Shockley-Reed-Hall, Auger, and radiative recombination rates) in the quantum well, under equilibrium and forward bias conditions. Electron blocking layer is based on AlaGa1-aN / Al b → cGa1-b → 1-cN / AldGa 1-dN, where a < d < b < c. A graded layer sandwiched between large bandgap AlGaN materials was found to be effective in simultaneously blocking electrons and providing polarization field enhanced carrier injection. The graded interlayer reduces polarization induced band bending and mitigates the related drawback of impediment of holes injection. Similarly on the n-side, the Alx → yGa1-x → 1-yN / AlzGa 1-zN (x < z < y) barrier acts as a hole blocking layer. The reduced carrier leakage and enhanced carrier density in the active region results in significant improvement in radiative recombination rate compared to a structure with the conventional rectangular EBL layers. The improvement in device performance comes from meticulously designing the hole and electron blocking layers to increase carrier injection efficiency. The quantum well based UV-LED was designed to emit at 280nm, which is an effective wavelength for water disinfection application.

Subnanometer Ga 2 O 3 Tunnelling Layer by Atomic Layer Deposition to Achieve 1.1 V Open-Circuit Potential in Dye-Sensitized Solar Cells

KAUST Repository

Chandiran, Aravind Kumar

2012-08-08

Herein, we present the first use of a gallium oxide tunnelling layer to significantly reduce electron recombination in dye-sensitized solar cells (DSC). The subnanometer coating is achieved using atomic layer deposition (ALD) and leading to a new DSC record open-circuit potential of 1.1 V with state-of-the-art organic D-π-A sensitizer and cobalt redox mediator. After ALD of only a few angstroms of Ga 2O 3, the electron back reaction is reduced by more than an order of magnitude, while charge collection efficiency and fill factor are increased by 30% and 15%, respectively. The photogenerated exciton separation processes of electron injection into the TiO 2 conduction band and the hole injection into the electrolyte are characterized in detail. © 2012 American Chemical Society.

A gas production system from methane hydrate layers by hot water injection and BHP control with radial horizontal wells

Energy Technology Data Exchange (ETDEWEB)

Yamakawa, T.; Ono, S.; Iwamoto, A.; Sugai, Y.; Sasaki, K. [Kyushu Univ., Fukuoka, Fukuoka (Japan)

2010-07-01

Reservoir characterization of methane hydrate (MH) bearing turbidite channel in the eastern Nankai Trough, in Japan has been performed to develop a gas production strategy. This paper proposed a gas production system from methane hydrate (MH) sediment layers by combining the hot water injection method and bottom hole pressure control at the production well using radial horizontal wells. Numerical simulations of the cylindrical homogeneous MH layer model were performed in order to evaluate gas production characteristics by the depressurization method with bottom hole pressure control. In addition, the effects of numerical block modeling and averaging physical properties of MH layers were presented. According to numerical simulations, combining the existing production system with hot water injection and bottom hole pressure control results in an outward expansion of the hot water chamber from the center of the MH layer with continuous gas production. 10 refs., 15 figs.

Low absorption loss p-AlGaN superlattice cladding layer for current-injection deep ultraviolet laser diodes

Energy Technology Data Exchange (ETDEWEB)

Martens, M.; Kuhn, C.; Ziffer, E.; Simoneit, T.; Rass, J.; Wernicke, T. [Institute of Solid State Physics, Technische Universität Berlin, Hardenbergstr. 36, EW 6-1, 10623 Berlin (Germany); Kueller, V.; Knauer, A.; Einfeldt, S.; Weyers, M. [Ferdinand-Braun-Institut, Leibniz-Institut für Höchstfrequenztechnik, Gustav-Kirchhoff-Str. 4, 12489 Berlin (Germany); Kneissl, M. [Institute of Solid State Physics, Technische Universität Berlin, Hardenbergstr. 36, EW 6-1, 10623 Berlin (Germany); Ferdinand-Braun-Institut, Leibniz-Institut für Höchstfrequenztechnik, Gustav-Kirchhoff-Str. 4, 12489 Berlin (Germany)

2016-04-11

Current injection into AlGaN-based laser diode structures with high aluminum mole fractions for deep ultraviolet emission is investigated. The electrical characteristics of laser diode structures with different p-AlGaN short period superlattice (SPSL) cladding layers with various aluminum mole fractions are compared. The heterostructures contain all elements that are needed for a current-injection laser diode including cladding and waveguide layers as well as an AlGaN quantum well active region emitting near 270 nm. We found that with increasing aluminum content in the p-AlGaN cladding, the diode turn-on voltage increases, while the series resistance slightly decreases. By introducing an SPSL instead of bulk layers, the operating voltage is significantly reduced. A gain guided broad area laser diode structure with transparent p-Al{sub 0.70}Ga{sub 0.30}N waveguide layers and a transparent p-cladding with an average aluminum content of 81% was designed for strong confinement of the transverse optical mode and low optical losses. Using an optimized SPSL, this diode could sustain current densities of more than 4.5 kA/cm{sup 2}.

Efficient small molecular organic light emitting diode with graphene cathode covered by a Sm layer with nano-hollows and n-doped by Bphen:Cs2CO3 in the hollows

Science.gov (United States)

Yao, Li; Li, Lei; Qin, Laixiang; Ma, Yaoguang; Wang, Wei; Meng, Hu; Jin, Weifeng; Wang, Yilun; Xu, Wanjin; Ran, Guangzhao; You, Liping; Qin, Guogang

2017-03-01

Graphene is a favorable candidate for electrodes of organic light emitting diodes (OLEDs). Graphene has quite a high work function of ˜4.5 eV, and has been extensively studied when used as anodes of OLEDs. In order to use graphene as a cathode, the electron injection barrier between the graphene cathode and the electron transport layer has to be low enough. Using 4,7-diphenyl-1,10-phenanthroline (Bphen):Cs2CO3 to n-dope graphene is a very good method, but the electron injection barrier between the n-doped graphene and Bphen:Cs2CO3 is still too high to be ˜1.0 eV. In this work, in order to further reduce the electron injection barrier, a novel method is suggested. On the graphene cathode, a Sm layer with a lot of nano-hollows, and subsequently a layer of Bphen:Cs2CO3, are deposited. The Bphen:Cs2CO3 can n-dope graphene in the nano-hollows, and the Fermi level of the graphene rises. The nano Sm layer is very easily oxidized. Oxygen adsorbed on the surface of graphene may react with Sm to form an O--Sm+ dipole layer. On the areas of the Sm oxide dipole layer without nano-hollows, the electron injection barrier can be further lowered by the dipole layer. Electrons tend to mainly inject through the lower electron barrier where the dipole layer exists. Based on this idea, an effective inverted small molecular OLED with the structure of graphene/1 nm Sm layer with a lot of nano-hollows/Bphen:Cs2CO3/Alq3:C545T/NPB/MoO3/Al is presented. The maximum current efficiency and maximum power efficiency of the OLED with a 1 nm Sm layer are about two and three times of those of the reference OLED without any Sm layer, respectively.

Observation of red electroluminescence from an Eu2O3/ p +-Si device and improved performance by introducing a Tb2O3 layer

International Nuclear Information System (INIS)

Yin, Xue; Wang, Shenwei; Mu, Guangyao; Wan, Guangmiao; Huang, Miaoling; Yi, Lixin

2017-01-01

We report red electroluminescence (EL) from an Eu 2 O 3 / p + -Si device with Eu 2 O 3 film annealed in oxygen ambient at 700 °C. The red EL is ascribed to the characteristic emissions of Eu 3+ ions in Eu 2 O 3 film and the luminescence mechanism is discussed in detail. In order to optimize the device performance, Eu 2 O 3 /Tb 2 O 3 multiple films were deposited on Si wafer, and the result showed EL intensity of the device was obviously enhanced and the turn-on voltage was reduced to about 10 V. Moreover, intensity ratio I ( 5 D 0 – 7 F 2 )/ I ( 5 D 0 – 7 F 1 ) was also significantly increased with the hypersensitive transition 5 D 0 – 7 F 2 as the most prominent group at about 611 nm. The improved performance was attributed to the added Tb 2 O 3 film that it can be served as the hole-injection layer to afford extra holes injected into the Eu 2 O 3 layer. (paper)

Preparation of Fe(3)O(4)@C@CNC multifunctional magnetic core/shell nanoparticles and their application in a signal-type flow-injection photoluminescence immunosensor.

Science.gov (United States)

Chu, Chengchao; Li, Meng; Li, Long; Ge, Shenguang; Ge, Lei; Yu, Jinghua; Yan, Mei; Song, Xianrang

2013-11-01

We describe here the preparation of carbon-coated Fe3O4 magnetic nanoparticles that were further fabricated into multifunctional core/shell nanoparticles (Fe3O4@C@CNCs) through a layer-by-layer self-assembly process of carbon nanocrystals (CNCs). The nanoparticles were applied in a photoluminescence (PL) immunosensor to detect the carcinoembryonic antigen (CEA), and CEA primary antibody was immobilized onto the surface of the nanoparticles. In addition, CEA secondary antibody and glucose oxidase were covalently bonded to silica nanoparticles. After stepwise immunoreactions, the immunoreagent was injected into the PL cell using a flow-injection PL system. When glucose was injected, hydrogen peroxide was obtained because of glucose oxidase catalysis and quenched the PL of the Fe3O4@C@CNC nanoparticles. The here proposed PL immunosensor allowed us to determine CEA concentrations in the 0.005–50 ng·mL-1 concentration range, with a detection limit of 1.8 pg·mL-1.

Cross correlation coefficients of turbulent boundary layer with micro-bubble injection

Energy Technology Data Exchange (ETDEWEB)

Claudia del Carmen Gutierrez-Torres [LABINTHAP-SEPI-ESIME, Instituto Politecnico Nacional, U.P. Adolfo Lopez Mateos Edif. 5 3er. Piso, Col Lindavista, C.P. 07738, Mexico, D. F. (Mexico); Yassin A Hassan; Jose Alfredo Jimenez-Bernal [Texas A and M University, College Station, Tx. 77843-3133 (United States)

2005-07-01

Full text of publication follows: Injection of micro-bubbles within the turbulent boundary layer has been investigated for a several years as a method to achieve drag reduction. However, the physical mechanism of this phenomenon is not fully understood yet. Experiments in a channel flow for single phase (water) and two phase (water and micro-bubbles) flows under different void fraction conditions are reported for a Reynolds number of 5128. Particle Image Velocimetry technique is used to measure instantaneous velocity fields. Consequently the cross-correlation coefficient Ruv can be calculated along the stream-wise direction for various different y{sup +} positions and along the normal direction for the fluctuating components of the velocity obtained from the instantaneous velocity fields. The experiments were carried out in a rectangular acrylic channel, whose dimensions are 4.8 m length, 20.6 cm wide and 5.6 cm height. Water was driven trough the channel by gravity from a tank, which was located 3 m above the channel. Then, water was conducted to a lower tank; from which water was pumped to the upper thank forming a closed loop. Upper tank's water level was kept constant through the tests to ensure constant flow rate trough the channel. The velocity field in the x-y plane was obtained by particle image velocimetry (PIV) at 3.15 m downstream from the channel inlet. A Nd:YAG laser with a wavelength of 532 nm (green light) and power of 350 mJ per pulse is utilized. The particles used for seeding have a diameter that goes from 6-9 {mu}m with a specific gravity almost identical to water s specific gravity. The laser light scattered from the seeding particles was recorded using a CCD Kodak Megaplus camera, Model ES 1.0, 1008 x 1018 pixels. The viewing area was 1.28 cm{sup 2} and was located close to the channel wall. The system recorded 30 velocity fields per second. Each velocity field was obtained from a pair of consecutive images capturing the second image of

Cross correlation coefficients of turbulent boundary layer with micro-bubble injection

International Nuclear Information System (INIS)

Claudia del Carmen Gutierrez-Torres; Yassin A Hassan; Jose Alfredo Jimenez-Bernal

2005-01-01

Full text of publication follows: Injection of micro-bubbles within the turbulent boundary layer has been investigated for a several years as a method to achieve drag reduction. However, the physical mechanism of this phenomenon is not fully understood yet. Experiments in a channel flow for single phase (water) and two phase (water and micro-bubbles) flows under different void fraction conditions are reported for a Reynolds number of 5128. Particle Image Velocimetry technique is used to measure instantaneous velocity fields. Consequently the cross-correlation coefficient Ruv can be calculated along the stream-wise direction for various different y + positions and along the normal direction for the fluctuating components of the velocity obtained from the instantaneous velocity fields. The experiments were carried out in a rectangular acrylic channel, whose dimensions are 4.8 m length, 20.6 cm wide and 5.6 cm height. Water was driven trough the channel by gravity from a tank, which was located 3 m above the channel. Then, water was conducted to a lower tank; from which water was pumped to the upper thank forming a closed loop. Upper tank's water level was kept constant through the tests to ensure constant flow rate trough the channel. The velocity field in the x-y plane was obtained by particle image velocimetry (PIV) at 3.15 m downstream from the channel inlet. A Nd:YAG laser with a wavelength of 532 nm (green light) and power of 350 mJ per pulse is utilized. The particles used for seeding have a diameter that goes from 6-9 μm with a specific gravity almost identical to water s specific gravity. The laser light scattered from the seeding particles was recorded using a CCD Kodak Megaplus camera, Model ES 1.0, 1008 x 1018 pixels. The viewing area was 1.28 cm 2 and was located close to the channel wall. The system recorded 30 velocity fields per second. Each velocity field was obtained from a pair of consecutive images capturing the second image of the pair 1 ms after

Investigating the effect of in ovo injection of silver nanoparticles on fat uptake and development in broiler and layer hatchlings

DEFF Research Database (Denmark)

Pineda, Lane Manalili; Chwalibog, André; Sawosz, Ewa

2012-01-01

consumption, CO2 production, and heat production, HP), fat uptake, and the development of broiler and layer hatchlings. AgNano concentrations (50, 75, and 100¿mg/kg) were injected in ovo at day 1 of incubation to different breeds of broiler and layer chicken embryos. Oxygen consumption and subsequently FU did......Nano affected metabolic rate and FU; however, it did not influence the development of hatchlings. This suggests that in ovo injection of AgNano reduces the need to use yolk fat as an energy source during embryonic development and consequently the remaining fat in the residual yolk sac may provide a potent...

Perceptions of community and family level IDU and HIV related stigma, disclosure decisions and experiences with layered stigma among HIV positive injection drug users in Vietnam

OpenAIRE

Rudolph, A.E.; Davis, W.W.; Quan, V.M.; Ha, T.V.; Minh, N.L.; Gregowski, A.; Salter, Megan; Celentano, D.D.; Go, V.

2011-01-01

This paper explores how perceived stigma and layered stigma related to injection drug use and being HIV positive influence the decision to disclose one’s HIV status to family and community and experiences with stigma following disclosure among a population of HIV positive male injection drug users (IDUs) in Thai Nguyen, Vietnam. In qualitative interviews conducted between 2007 and 2008, 25 HIV positive male IDUs described layered stigma in their community but an absence of layered stigma with...

The emotion regulation questionnaire in women with cancer: A psychometric evaluation and an item response theory analysis.

Science.gov (United States)

Brandão, Tânia; Schulz, Marc S; Gross, James J; Matos, Paula Mena

2017-10-01

Emotion regulation is thought to play an important role in adaptation to cancer. However, the emotion regulation questionnaire (ERQ), a widely used instrument to assess emotion regulation, has not yet been validated in this context. This study addresses this gap by examining the psychometric properties of the ERQ in a sample of Portuguese women with cancer. The ERQ was administered to 204 women with cancer (mean age = 48.89 years, SD = 7.55). Confirmatory factor analysis and item response theory analysis were used to examine psychometric properties of the ERQ. Confirmatory factor analysis confirmed the 2-factor solution proposed by the original authors (expressive suppression and cognitive reappraisal). This solution was invariant across age and type of cancer. Item response theory analyses showed that all items were moderately to highly discriminant and that items are better suited for identifying moderate levels of expressive suppression and cognitive reappraisal. Support was found for the internal consistency and test-retest reliability of the ERQ. The pattern of relationships with emotional control, alexithymia, emotional self-efficacy, attachment, and quality of life provided evidence of the convergent and concurrent validity for both dimensions of the ERQ. Overall, the ERQ is a psychometrically sound approach for assessing emotion regulation strategies in the oncological context. Clinical implications are discussed. Copyright © 2016 John Wiley & Sons, Ltd.

Monitoring a pilot CO2 injection experiment in a shallow aquifer using 3D cross-well electrical resistance tomography

Science.gov (United States)

Yang, X.; Lassen, R. N.; Looms, M. C.; Jensen, K. H.

2014-12-01

Three dimensional electrical resistance tomography (ERT) was used to monitor a pilot CO2 injection experiment at Vrøgum, Denmark. The purpose was to evaluate the effectiveness of the ERT method for monitoring the two opposing effects from gas-phase and dissolved CO2 in a shallow unconfined siliciclastic aquifer. Dissolved CO2 increases water electrical conductivity (EC) while gas phase CO2 reduce EC. We injected 45kg of CO2 into a shallow aquifer for 48 hours. ERT data were collected for 50 hours following CO2 injection. Four ERT monitoring boreholes were installed on a 5m by 5m square grid and each borehole had 24 electrodes at 0.5 m electrode spacing at depths from 1.5 m to 13 m. ERT data were inverted using a difference inversion algorithm for bulk EC. 3D ERT successfully detected the CO2 plume distribution and growth in the shallow aquifer. We found that the changes of bulk EC were dominantly positive following CO2 injection, indicating that the effect of dissolved CO2 overwhelmed that of gas phase CO2. The pre-injection baseline resistivity model clearly showed a three-layer structure of the site. The electrically more conductive glacial sand layer in the northeast region are likely more permeable than the overburden and underburden and CO2 plumes were actually confined in this layer. Temporal bulk EC increase from ERT agreed well with water EC and cross-borehole ground penetrating radar data. ERT monitoring offers a competitive advantage over water sampling and GPR methods because it provides 3D high-resolution temporal tomographic images of CO2 distribution and it can also be automated for unattended operation. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under contract DE-AC52-07NA27344. Lawrence Livermore National Security, LLC. LLNL IM release#: LLNL-PROC-657944.

Effect of additive gases and injection methods on chemical dry etching of silicon nitride, silicon oxynitride, and silicon oxide layers in F2 remote plasmas

International Nuclear Information System (INIS)

Yun, Y. B.; Park, S. M.; Kim, D. J.; Lee, N.-E.; Kim, K. S.; Bae, G. H.

2007-01-01

The authors investigated the effects of various additive gases and different injection methods on the chemical dry etching of silicon nitride, silicon oxynitride, and silicon oxide layers in F 2 remote plasmas. N 2 and N 2 +O 2 gases in the F 2 /Ar/N 2 and F 2 /Ar/N 2 /O 2 remote plasmas effectively increased the etch rate of the layers. The addition of direct-injected NO gas increased the etch rates most significantly. NO radicals generated by the addition of N 2 and N 2 +O 2 or direct-injected NO molecules contributed to the effective removal of nitrogen and oxygen in the silicon nitride and oxide layers, by forming N 2 O and NO 2 by-products, respectively, and thereby enhancing SiF 4 formation. As a result of the effective removal of the oxygen, nitrogen, and silicon atoms in the layers, the chemical dry etch rates were enhanced significantly. The process regime for the etch rate enhancement of the layers was extended at elevated temperature

Enhanced performance of inverted organic photovoltaic cells using CNTs-TiO(X) nanocomposites as electron injection layer.

Science.gov (United States)

Zhang, Hong; Xu, Meifeng; Cui, Rongli; Guo, Xihong; Yang, Shangyuan; Liao, Liangsheng; Jia, Quanjie; Chen, Yu; Dong, Jinquan; Sun, Baoyun

2013-09-06

In this study, we fabricated inverted organic photovoltaic cells with the structure ITO/carbon nanotubes (CNTs)-TiO(X)/P3HT:PCBM/MoO₃/Al by spin casting CNTs-TiO(X) nanocomposite (CNTs-TiO(X)) as the electron injection layer onto ITO/glass substrates. The power conversion efficiency (PCE) of the 0.1 wt% single-walled nanotubes (SWNTs)-TiO(X) nanocomposite device was almost doubled compared with the TiO(X) device, but with increasing concentration of the incorporated SWNTs in the TiO(X) film, the performance of the devices appeared to decrease rapidly. Devices with multi-walled NTs in the TiO(X) film have a similar trend. This phenomenon mainly depends on the inherent physical and chemical characteristics of CNTs such as their high surface area, their electron-accepting properties and their excellent carrier mobility. However, with increasing concentration of CNTs, CNTs-TiO(X) current leakage pathways emerged and also a recombination of charges at the interfaces. In addition, there was a significant discovery. The incorporated CNTs were highly conducive to enhancing the degree of crystallinity and the ordered arrangement of the P3HT in the active layers, due to the intermolecular π-π stacking interactions between CNTs and P3HT.

Physics of the current injection process during localized helicity injection

Science.gov (United States)

Hinson, Edward Thomas

An impedance model has been developed for the arc-plasma cathode electron current source used in localized helicity injection tokamak startup. According to this model, a potential double layer (DL) is established between the high-density arc plasma (narc ˜ 1021 m-3) in the electron source, and the less-dense external tokamak edge plasma (nedge ˜ 10 18 m-3) into which current is injected. The DL launches an electron beam at the applied voltage with cross-sectional area close to that of the source aperture: Ainj ≈ 2 cm 2. The injected current, Iinj, increases with applied voltage, Vinj, according to the standard DL scaling, Iinj ˜ V(3/2/ inj), until the more restrictive of two limits to beam density nb arises, producing Iinj ˜ V(1/2/inj), a scaling with beam drift velocity. For low external tokamak edge density nedge, space-charge neutralization of the intense electron beam restricts the injected beam density to nb ˜ nedge. At high Jinj and sufficient edge density, the injected current is limited by expansion of the DL sheath, which leads to nb ˜ narc. Measurements of narc, Iinj , nedge, Vinj, support these predicted scalings, and suggest narc as a viable control actuator for the source impedance. Magnetic probe signals ≈ 300 degrees toroidally from the injection location are consistent with expectations for a gyrating, coherent electron beam with a compact areal cross-section. Technological development of the source has allowed an extension of the favorable Iinj ˜ V(1/2/inj) to higher power without electrical breakdown.

Tailoring of polarization in electron blocking layer for electron confinement and hole injection in ultraviolet light-emitting diodes

International Nuclear Information System (INIS)

Lu, Yu-Hsuan; Pilkuhn, Manfred H.; Fu, Yi-Keng; Chu, Mu-Tao; Huang, Shyh-Jer; Su, Yan-Kuin; Wang, Kang L.

2014-01-01

The influence of the AlGaN electron blocking layer (EBL) with graded aluminum composition on electron confinement and hole injection in AlGaN-based ultraviolet light-emitting diodes (LEDs) are investigated. The light output power of LED with graded AlGaN EBL was markedly improved, comparing to LED with conventional EBL. In experimental results, a high increment of 86.7% can be obtained in light output power. Simulation analysis shows that via proper modification of the barrier profile from the last barrier of the active region to EBL, not only the elimination of electron overflow to p-type layer can be achieved but also the hole injection into the active region can be enhanced, compared to a conventional LED structure. The dominant factor to the performance improvement is shown to be the modulation of polarization field by the graded Al composition in EBL

Tailoring of polarization in electron blocking layer for electron confinement and hole injection in ultraviolet light-emitting diodes

Energy Technology Data Exchange (ETDEWEB)

Lu, Yu-Hsuan; Pilkuhn, Manfred H. [Department of Electrical Engineering, Institute of Microelectronics and Advanced Optoelectronic Technology Center, National Cheng Kung University, Tainan 70101, Taiwan (China); Fu, Yi-Keng; Chu, Mu-Tao [Electronics and Optoelectronics Research Laboratories, Industrial Technology Research Institute, Hsinchu 31040, Taiwan (China); Huang, Shyh-Jer, E-mail: yksu@mail.ncku.edu.tw, E-mail: totaljer48@gmail.com [Department of Electrical Engineering, Institute of Microelectronics and Advanced Optoelectronic Technology Center, National Cheng Kung University, Tainan 70101, Taiwan (China); Department of Electrical Engineering, University of California at Los Angeles, Los Angeles, California 90095 (United States); Su, Yan-Kuin, E-mail: yksu@mail.ncku.edu.tw, E-mail: totaljer48@gmail.com [Department of Electrical Engineering, Institute of Microelectronics and Advanced Optoelectronic Technology Center, National Cheng Kung University, Tainan 70101, Taiwan (China); Department of Electronic Engineering, Kun-Shan University, Tainan 71003, Taiwan (China); Wang, Kang L. [Department of Electrical Engineering, University of California at Los Angeles, Los Angeles, California 90095 (United States)

2014-03-21

The influence of the AlGaN electron blocking layer (EBL) with graded aluminum composition on electron confinement and hole injection in AlGaN-based ultraviolet light-emitting diodes (LEDs) are investigated. The light output power of LED with graded AlGaN EBL was markedly improved, comparing to LED with conventional EBL. In experimental results, a high increment of 86.7% can be obtained in light output power. Simulation analysis shows that via proper modification of the barrier profile from the last barrier of the active region to EBL, not only the elimination of electron overflow to p-type layer can be achieved but also the hole injection into the active region can be enhanced, compared to a conventional LED structure. The dominant factor to the performance improvement is shown to be the modulation of polarization field by the graded Al composition in EBL.

Effects of multiple intravitreal anti-VEGF injections on retinal nerve fiber layer and intraocular pressure: a comparative clinical study.

Science.gov (United States)

Sobacı, Güngör; Güngör, Rıza; Ozge, Gökhan

2013-01-01

To determine the effect of multiple injections of ranibizumab or bevacizumab on retinal nerve fiber layer (RNFL) and intraocular pressure (IOP) in patients with age-related macular degeneration (AMD). This retrospective study includes 35 eyes of 35 patients treated with intravitreal bevacizumab (IVB, 1.25mg/0.05mL) and 30 eyes of 30 patients with intravitreal ranibizumab (IVR, 0.5mg/0.05mL) who had Fast RNFL analysis (Stratus™); IOP measurements were taken 30 minutes and 24 hours after each injection. The mean ages were 68.0±7.5 and 69.1±7.7 years in the IVR and IVB groups, respectively (P=0.55). They underwent (6.3±1.9) and (5.1±1.3) injections (P=0.07) over (13.6±2.1) and (14.05±2.6) months (P=0.45) in the IVR and IVB groups, respectively. Changes in overall and temporal RNFL thickness in IVR-treated eyes (105.3±6.9µm and 74.4±11.2µm) were not different from those in untreated eyes in the IVR group (104.6± 8.4µm and 75.1±12.6µm) (P=0.57 and P=0.41, respectively). Similarly, overall and temporal RNFL thickness in IVB-treated eyes (105.8±8.1µm and 74.5±11.8µm) were not different from those in untreated eyes in the IVB group (104.6±8µm and 74.8±12.9µm) (P=0.42 and P=0.80, respectively). The frequencies of IOP rise (P=0.60) and changes in RNFL thickness from baseline (P=0.16) were comparable between groups. Repeated intravitreal injection of ranibizumab or bevacizumab does not seem have adverse effects on RNFL thickness or IOP in wet AMD patients.

Enhancement of electron injection in inverted bottom-emitting organic light-emitting diodes using Al/LiF compound thin film

Science.gov (United States)

Nie, Qu-yang; Zhang, Fang-hui

2018-05-01

The inverted bottom-emitting organic light-emitting devices (IBOLEDs) were prepared, with the structure of ITO/Al ( x nm)/LiF (1 nm)/Bphen (40 nm)/CBP: GIr1 (14%):R-4b (2%) (10 nm)/BCP (3 nm)/CBP:GIr1 (14%):R-4b (2%) (20 nm)/TCTA (10 nm)/NPB (40 nm)/MoO3 (40 nm)/Al (100 nm), where the thickness of electron injection layer Al ( x) are 0 nm, 2 nm, 3 nm, 4 nm and 5 nm, respectively. In this paper, the electron injection condition and luminance properties of inverted devices were investigated by changing the thickness of Al layer in Al/LiF compound thin film. It turns out that the introduction of Al layer can improve electron injection of the devices dramatically. Furthermore, the device exerts lower driving voltage and higher current efficiency when the thickness of electron injection Al layer is 3 nm. For example, the current efficiency of the device with 3-nm-thick Al layer reaches 19.75 cd·A-1 when driving voltage is 7 V, which is 1.24, 1.17 and 17.03 times larger than those of the devices with 2 nm, 4 nm and 5 nm Al layer, respectively. The device property reaches up to the level of corresponding conventional device. In addition, all inverted devices with electron injection Al layer show superior stability of color coordinate due to the adoption of co-evaporation emitting layer and BCP spacer-layer, and the color coordinate of the inverted device with 3-nm-thick Al layer only changes from (0.580 6, 0.405 6) to (0.532 8, 0.436 3) when driving voltage increases from 6 V to 10 V.

The occurrence and distribution of pharmaceutical compounds in the effluents of a major sewage treatment plant in Northern Taiwan and the receiving coastal waters

International Nuclear Information System (INIS)

Fang, Tien-Hsi; Nan, Fan-Hua; Chin, Tzong-Shean; Feng, Hui-Min

2012-01-01

The pharmaceutical residues in waste water from the largest sewage treatment plant (STP) in Northern Taiwan and in seawater around the effluent discharged area were determined. An environmental risk assessment for the marine environment was conducted based on the environment risk quotient (ERQ). The concentrations of the analyzed compounds in STP influent and effluent were generally higher than those found in coastal seawater. Relatively higher values were found at the estuarine mouth and the discharged area, suggesting that the STP effluent is a point source. The removal efficiency and half life of the analyzed compounds were 6.3–46.8% and 3–18 days, respectively. The ERQ value theoretical calculation was generally greater than 1. However, when the measured concentrations replaced the predicated concentrations, the ERQ values were considerably lower than 1. Therefore, our results call for a re-evaluation of the risks posed by pharmaceuticals to coastal marine ecosystems in Northern Taiwan.

Carrier injection and recombination processes in perovskite CH3NH3PbI3 solar cells studied by electroluminescence spectroscopy

Science.gov (United States)

Handa, Taketo; Okano, Makoto; Tex, David M.; Shimazaki, Ai; Aharen, Tomoko; Wakamiya, Atsushi; Kanemitsu, Yoshihiko

2016-02-01

Organic-inorganic hybrid perovskite materials, CH3NH3PbX3 (X = I and Br), are considered as promising candidates for emerging thin-film photovoltaics. For practical implementation, the degradation mechanism and the carrier dynamics during operation have to be clarified. We investigated the degradation mechanism and the carrier injection and recombination processes in perovskite CH3NH3PbI3 solar cells using photoluminescence (PL) and electroluminescence (EL) imaging spectroscopies. By applying forward bias-voltage, an inhomogeneous distribution of the EL intensity was clearly observed from the CH3NH3PbI3 solar cells. By comparing the PL- and EL-images, we revealed that the spatial inhomogeneity of the EL intensity is a result of the inhomogeneous luminescence efficiency in the perovskite layer. An application of bias-voltage for several tens of minutes in air caused a decrease in the EL intensity and the conversion efficiency of the perovskite solar cells. The degradation mechanism of perovskite solar cells under bias-voltage in air is discussed.

A theoretical study of mixing downstream of transverse injection into a supersonic boundary layer

Science.gov (United States)

Baker, A. J.; Zelazny, S. W.

1972-01-01

A theoretical and analytical study was made of mixing downstream of transverse hydrogen injection, from single and multiple orifices, into a Mach 4 air boundary layer over a flat plate. Numerical solutions to the governing three-dimensional, elliptic boundary layer equations were obtained using a general purpose computer program. Founded upon a finite element solution algorithm. A prototype three-dimensional turbulent transport model was developed using mixing length theory in the wall region and the mass defect concept in the outer region. Excellent agreement between the computed flow field and experimental data for a jet/freestream dynamic pressure ratio of unity was obtained in the centerplane region of the single-jet configuration. Poorer agreement off centerplane suggests an inadequacy of the extrapolated two-dimensional turbulence model. Considerable improvement in off-centerplane computational agreement occured for a multi-jet configuration, using the same turbulent transport model.

Surface tailoring of newly developed amorphous Znsbnd Sisbnd O thin films as electron injection/transport layer by plasma treatment: Application to inverted OLEDs and hybrid solar cells

Science.gov (United States)

Yang, Hongsheng; Kim, Junghwan; Yamamoto, Koji; Xing, Xing; Hosono, Hideo

2018-03-01

We report a unique amorphous oxide semiconductor Znsbnd Sisbnd O (a-ZSO) which has a small work function of 3.4 eV for as-deposited films. The surface modification of a-ZSO thin films by plasma treatments is examined to apply it to the electron injection/transport layer of organic devices. It turns out that the energy alignment and exciton dissociation efficiency at a-ZSO/organic semiconductor interface significantly changes by choosing different gas (oxygen or argon) for plasma treatments (after a-ZSO was exposed to atmospheric environment for 5 days). In situ ultraviolet photoelectron spectroscopy (UPS) measurement reveals that the work function of a-ZSO is increased to 4.0 eV after an O2-plasma treatment, while the work function of 3.5 eV is recovered after an Ar-plasma treatment which indicates this treatment is effective for surface cleaning. To study the effects of surface treatments to device performance, OLEDs and hybrid polymer solar cells with O2-plasma or Ar-plasma treated a-ZSO are compared. Effects of these surface treatments on performance of inverted OLEDs and hybrid polymer solar cells are examined. Ar-plasma treated a-ZSO works well as the electron injection layer in inverted OLEDs (Alq3/a-ZSO) because the injection barrier is small (∼ 0.1 eV). On the other hands, O2-plasma treated a-ZSO is more suitable for application to hybrid solar cells which is benefiting from higher exciton dissociation efficiency at polymer (P3HT)/ZSO interface.

Efficient and color-saturated inverted bottom-emitting organic light-emitting devices with a semi-transparent metal-assisted electron injection layer

Energy Technology Data Exchange (ETDEWEB)

Ho, Meng-Huan, E-mail: kinneas.ac94g@nctu.edu.t [Department of Applied Chemistry, National Chiao Tung University, 210 R, CPT Building, 1001 Ta Hsueh Road, Hsinchu 300, Taiwan (China); Wu, Chang-Yen [Department of Photonics, National Chiao Tung University, Hsinchu 300, Taiwan (China); Chen, Teng-Ming [Department of Applied Chemistry, National Chiao Tung University, 210 R, CPT Building, 1001 Ta Hsueh Road, Hsinchu 300, Taiwan (China); Chen, Chin H. [Display Institute, Microelectronics and Information Systems Research Center, National Chiao Tung University, Hsinchu 300, Taiwan (China)

2011-01-15

We report the development of highly efficient and color-saturated green fluorescent 10-(2-benzothiazolyl)-1,1,7,7-tetramethyl-2,3,6,7-tetrahydro-1H,5H, 11H-benzo[l]pyrano-[6,7,8-ij]quinolizin-11-one dye-doped inverted bottom-emitting organic light-emitting diode (IBOLED). This was enabled by the insertion of a silver (Ag) based semi-transparent metal-assisted electron injection layer between the ITO cathode and n-doped electron transporting layer. This IBOLED with ITO/Ag bilayer cathode with its synergistic microcavity effect achieved luminous efficiencies of 20.7 cd/A and 12.4 lm/W and a saturated CIE{sub x,y} of (0.22, 0.72) at 20 mA/cm{sup 2}, which are twice better than those of the conventional OLED and have over 60% improvement on IBOLED without ITO/Ag bilayer cathode.

Research and embedded implementation of Layer 3 switch

Science.gov (United States)

Song, Jin; Cheng, Zijing

2009-12-01

In the internetworking world, switches and routers have been deployed for workgroup and enterprise connectivity. In the past, switches mainly operated at Layer 2 (they were extensions of bridges), while routers were clearly Layer3 devices. Recently, the line has blurred and switches operating at Layer 3 are becoming more popular. This paper explains the Linux Bridge, Layer 2 Switches, Virtual LAN (VLAN) and Layer 3 Switches. The flow chart of Layer 3 switches and working routine related to Layer 3 switch technology were investigated in detail. This paper presents a new method to implement layer 3 switching that is entirely accomplished in software and is embedded implemented by code transplanting based on PowerPC 460GT platform.

SPEAR 3 INJECTION KICKER

International Nuclear Information System (INIS)

2002-01-01

The design of the SPEAR 3 injection kicker system is presented. This system will include three kicker magnets and their associated pulsers. The magnet design is based on the DELTA kicker magnets, which present a low RF impedance to the beam, and are relatively straight-forward to construct. The pulsers use cascaded IGBT stages that are based on the modulator pulsers developed by a SLAC/LLNL collaboration for the NLC. Design considerations and the results of prototype tests will be discussed

Impact of ultra-thin Al2O3-y layers on TiO2-x ReRAM switching characteristics

Science.gov (United States)

Trapatseli, Maria; Cortese, Simone; Serb, Alexander; Khiat, Ali; Prodromakis, Themistoklis

2017-05-01

Transition metal-oxide resistive random access memory devices have demonstrated excellent performance in switching speed, versatility of switching and low-power operation. However, this technology still faces challenges like poor cycling endurance, degradation due to high electroforming (EF) switching voltages and low yields. Approaches such as engineering of the active layer by doping or addition of thin oxide buffer layers have been often adopted to tackle these problems. Here, we have followed a strategy that combines the two; we have used ultra-thin Al2O3-y buffer layers incorporated between TiO2-x thin films taking into account both 3+/4+ oxidation states of Al/Ti cations. Our devices were tested by DC and pulsed voltage sweeping and in both cases demonstrated improved switching voltages. We believe that the Al2O3-y layers act as reservoirs of oxygen vacancies which are injected during EF, facilitate a filamentary switching mechanism and provide enhanced filament stability, as shown by the cycling endurance measurements.

BEAMS3D Neutral Beam Injection Model

Energy Technology Data Exchange (ETDEWEB)

Lazerson, Samuel

2014-04-14

With the advent of applied 3D fi elds in Tokamaks and modern high performance stellarators, a need has arisen to address non-axisymmetric effects on neutral beam heating and fueling. We report on the development of a fully 3D neutral beam injection (NBI) model, BEAMS3D, which addresses this need by coupling 3D equilibria to a guiding center code capable of modeling neutral and charged particle trajectories across the separatrix and into the plasma core. Ionization, neutralization, charge-exchange, viscous velocity reduction, and pitch angle scattering are modeled with the ADAS atomic physics database [1]. Benchmark calculations are presented to validate the collisionless particle orbits, neutral beam injection model, frictional drag, and pitch angle scattering effects. A calculation of neutral beam heating in the NCSX device is performed, highlighting the capability of the code to handle 3D magnetic fields.

Spin-injection into epitaxial graphene on silicon carbide

Science.gov (United States)

Konishi, Keita; Cui, Zhixin; Hiraki, Takahiro; Yoh, Kanji

2013-09-01

We have studied the spin-injection properties in epitaxial graphene on SiC. The ferromagnetic metal (FM) electrodes were composed of a tunnel barrier layer AlOx (14 Å) and a ferromagnetic Co (600 Å) layer. We have successfully observed the clear resistance peaks indicating spin-injection both in the "local" and "non-local" spin measurement set-ups at low temperatures. We estimate spin-injection rate of 1% based on "non-local" measurement and 1.6% based on local measurements. Spin-injection rate of multilayer graphene by mechanical exfoliation method was twice as high as single layer graphene on SiC based on "local" measurement.

Gallium arsenide injection lasers

International Nuclear Information System (INIS)

Thompson, G.H.B.

1975-01-01

The semiconductor injection laser includes a thin inner GaAs p-n junction layer between two outer GaAlAs layers which are backed by further thin outer GaAlAs layers with a heavier doping of AlAs. This reduces optical losses. Optical energy is further confined within the inner layers and the lasing threshold reduced by added outer GaAs layers of low electrical and thermal resistivity

High performance GaN-based LEDs on patterned sapphire substrate with patterned composite SiO2/Al2O3 passivation layers and TiO2/Al2O3 DBR backside reflector.

Science.gov (United States)

Guo, Hao; Zhang, Xiong; Chen, Hongjun; Zhang, Peiyuan; Liu, Honggang; Chang, Hudong; Zhao, Wei; Liao, Qinghua; Cui, Yiping

2013-09-09

GaN-based light-emitting diodes (LEDs) on patterned sapphire substrate (PSS) with patterned composite SiO(2)/Al(2)O(3) passivation layers and TiO(2)/Al(2)O(3) distributed Bragg reflector (DBR) backside reflector have been proposed and fabricated. Highly passivated Al(2)O(3) layer deposited on indium tin oxide (ITO) layer with excellent uniformity and quality has been achieved with atomic layer deposition (ALD) technology. With a 60 mA current injection, an enhancement of 21.6%, 59.7%, and 63.4% in the light output power (LOP) at 460 nm wavelength was realized for the LED with the patterned composite SiO(2)/Al(2)O(3) passivation layers, the LED with the patterned composite SiO(2)/Al(2)O(3) passivation layers and Ag mirror + 3-pair TiO(2)/SiO(2) DBR backside reflector, and the LED with the patterned composite SiO(2)/Al(2)O(3) passivation layer and Ag mirror + 3-pair ALD-grown TiO(2)/Al(2)O(3) DBR backside reflector as compared with the conventional LED only with a single SiO(2) passivation layer, respectively.

Asymmetric temporal integration of layer 4 and layer 2/3 inputs in visual cortex.

Science.gov (United States)

Hang, Giao B; Dan, Yang

2011-01-01

Neocortical neurons in vivo receive concurrent synaptic inputs from multiple sources, including feedforward, horizontal, and feedback pathways. Layer 2/3 of the visual cortex receives feedforward input from layer 4 and horizontal input from layer 2/3. Firing of the pyramidal neurons, which carries the output to higher cortical areas, depends critically on the interaction of these pathways. Here we examined synaptic integration of inputs from layer 4 and layer 2/3 in rat visual cortical slices. We found that the integration is sublinear and temporally asymmetric, with larger responses if layer 2/3 input preceded layer 4 input. The sublinearity depended on inhibition, and the asymmetry was largely attributable to the difference between the two inhibitory inputs. Interestingly, the asymmetric integration was specific to pyramidal neurons, and it strongly affected their spiking output. Thus via cortical inhibition, the temporal order of activation of layer 2/3 and layer 4 pathways can exert powerful control of cortical output during visual processing.

Techniques For Injection Of Pre-Charaterized Dust Into The Scrape Off Layer Of Fusion Plasma

International Nuclear Information System (INIS)

Roquemore, A.L.; John, B.; Friesen, F.; Hartzfeld, K.; Mansfield, D.K.

2011-01-01

Introduction of micron-sized dust into the scrape-off layer (SOL) of a plasma has recently found many applications aimed primarily at determining dust behavior in future fusion reactors. The dust particles are typically composed of materials intrinsic to a fusion reactor. On DIII-D and TEXTOR carbon dust has been introduced into the SOL using a probe inserted from below into the divertor region. On NSTX, both Li and tungsten dust have been dropped from the top of the machine into the SOL throughout the duration of a discharge, by utilizing a vibrating piezoelectric based particle dropper. The original particle dropper was developed to inject passivated Li powder ∼ 40 μm in diameter into the SOL to enhance plasma performance. A simplified version of the dropper was developed to introduce trace amounts of tungsten powder for only a few discharges, thus not requiring a large powder reservoir. The particles emit visible light from plasma interactions and can be tracked by either spectroscopic means or by fast frame rate visible cameras. This data can then be compared with dust transport codes such as DUSTT to make predictions of dust behavior in next-step devices such as ITER. For complete modeling results, it is desired to be able to inject pre-characterized dust particles in the SOL at various known poloidal locations, including near the vessel midplane. Purely mechanical methods of injecting particles are presently being studied using a modified piezoelectric-based powder dropper as a particle source and one of several piezo-based transducers to deflect the particles into the SOL. Vibrating piezo fans operating at 60 Hz with a deflection of ±2.5 cm can impart a significant horizontal boost in velocity. The highest injection velocities are expected from rotating paddle wheels capable of injecting particles at 10's of meters per second depending primarily on the rotation velocity and diameter of the wheel. Several injection concepts have been tested and will be

Asymmetric Temporal Integration of Layer 4 and Layer 2/3 Inputs in Visual Cortex

OpenAIRE

Hang, Giao B.; Dan, Yang

2010-01-01

Neocortical neurons in vivo receive concurrent synaptic inputs from multiple sources, including feedforward, horizontal, and feedback pathways. Layer 2/3 of the visual cortex receives feedforward input from layer 4 and horizontal input from layer 2/3. Firing of the pyramidal neurons, which carries the output to higher cortical areas, depends critically on the interaction of these pathways. Here we examined synaptic integration of inputs from layer 4 and layer 2/3 in rat visual cortical slices...

Autoradiographic localization of glucocorticosteriod binding sites in rat brain after in vivo injection of [3H]RU 28362

International Nuclear Information System (INIS)

Sarrieau, Alain; Dussaillant, Monique; Rostene, William

1988-01-01

The autoradiographic distribution of glucocorticosteriod binding sites in the brain of adrenalectomized rats was studied following in vivo injection of a potent synthetic glucocorticosteriod agonist [ 3 H]RU 28362. Analysis of the autoradiograms revealed a specific and dense labelling in the pyramidal cell layer of the Ammon's horn and in the granular cell layer of the dentate gyrus of the hippocampus. In the hypothalmus, the labelling was particularly high in the paraventricular nucleus (site of CRF synthesis), the arcuate, periventricular and the supraoptic nuclei as well as in the median eminence. Autoradiograms also revealed the presence of[ 3 H]RU 28362 binding sites in several brain regions including the amygdala, the pineal gland, the entorhinal cortex, the interpeduncular, interfascicular and dorsal raphe nuclei, the central grey and the substantia nigra suggesting possible effects of glucocorticosteriods in these structures (author)

Two stacked tandem white organic light-emitting diodes employing WO3 as a charge generation layer

Science.gov (United States)

Bin, Jong-Kwan; Lee, Na Yeon; Lee, SeungJae; Seo, Bomin; Yang, JoongHwan; Kim, Jinook; Yoon, Soo Young; Kang, InByeong

2016-09-01

Recently, many studies have been conducted to improve the electroluminescence (EL) performance of organic lightemitting diodes (OLEDs) by using appropriate organic or inorganic materials as charge generation layer (CGL) for their application such as full color displays, backlight units, and general lighting source. In a stacked tandem white organic light-emitting diodes (WOLEDs), a few emitting units are electrically interconnected by a CGL, which plays the role of generating charge carriers, and then facilitate the injection of it into adjacent emitting units. In the present study, twostacked WOLEDs were fabricated by using tungsten oxide (WO3) as inorganic charge generation layer and 1,4,5,8,9,11- hexaazatriphenylene hexacarbonitrile (HAT-CN) as organic charge generation layer (P-CGL). Organic P-CGL materials were used due to their ease of use in OLED fabrication as compared to their inorganic counterparts. To obtain high efficiency, we demonstrate two-stacked tandem WOLEDs as follows: ITO/HIL/HTL/HTL'/B-EML/ETL/N-CGL/P-CGL (WO3 or HAT-CN)/HTL″/YG-EML/ETL/LiF/Al. The tandem devices with blue- and yellow-green emitting layers were sensitive to the thickness of an adjacent layer, hole transporting layer for the YG emitting layer. The WOLEDs containing the WO3 as charge generation layer reach a higher power efficiency of 19.1 lm/W and the current efficiency of 51.2 cd/A with the white color coordinate of (0.316, 0.318) than the power efficiency of 13.9 lm/W, and the current efficiency of 43.7 cd/A for organic CGL, HAT-CN at 10 mA/cm2, respectively. This performance with inserting WO3 as CGL exhibited the highest performance with excellent CIE color coordinates in the two-stacked tandem OLEDs.

Long-term stability of a one-dimensional current-driven double layer

International Nuclear Information System (INIS)

Hori, N.; Yamamoto, T.

1988-01-01

Long-term (>an electron transit time over the system) stability of a one-dimensional current-driven double layer is studied by numerical experiments using particles. In these experiments, the potential difference across the system is self-consistently determined by the space charge distributions inside the system. Each boundary of the system supplies a nondrifting half-Maxwellian plasma. The current density is increased by increasing the number density of the source plasma at the injection (right) boundary. A double layer can be developed by injection of a sufficiently high current density. For a fixed level of current injection, plasmas carrying no current with various densities (n/sup ts/ 0 ) are loaded on the left side of the system. Whether or not the generated double layer can maintain its potential drop for a long period depends on the density (n/sup ts/ 0 ) relative to the initial density (n/sup */ 0 ) near the injection boundary: (1) the double layer is found to grow when n/sup ts/ 0 = n/sup */ 0 ; (2) the steady double layer is seen for a long period when n/sup ts/ 0 approx. >n/sup */ 0 ; (3) the double layer is found to decay when n/sup ts/ 0 is even higher than n/sup */ 0 . A new concept of the current polarizability P/sub c/ = J/n/sup number/ is introduced for understanding these results, where J is the current density flowing through the double layer and n/sup number/ is the plasma density at the injection front, i.e., the low-potential edge of the double layer

Simultaneous Suppression of IMD3 and IMD5 in Space TWT by IMD3 and 2HD Signal Injection

Directory of Open Access Journals (Sweden)

Dongming Zhao

2017-01-01

Full Text Available This paper presents a signal injection technology showing significant reductions in both 3rd-order and 5th-order intermodulation distortions (IMD3 and IMD5 in space traveling wave tube (STWT. By applying the IMD3 to the IMD5 ratio (TFR as measures of location, the simultaneous suppressions of IMD3 and IMD5 in TWT are achieved by second harmonic distortion (2HD and IMD3 injection. According to the research on theoretical analysis and computer simulation, the optimum amplitude and phase parameters of the injected signal for maximum simultaneous suppressions are obtained. Then an experiment system is established based on vector network analyzer, optimum TFR are 2.1 dB and 12.5 dB, respectively, by second harmonic and IM3 injection, and the output powers of IMD3 and IMD5 were decreased. TFR with IMD3 injection is smaller than that with second harmonic injection in STWT, and the experiment system is more straightforward and easy to operate. Thus, the IMD3 injection performs better than that of second harmonic injection to suppress IMD5s for the narrow-band STWT.

An investigation of methods for injecting emissions from boreal wildfires using WRF-Chem during ARCTAS

Science.gov (United States)

Sessions, W. R.; Fuelberg, H. E.; Kahn, R. A.; Winker, D. M.

2011-06-01

The Weather Research and Forecasting Model (WRF) is considered a "next generation" mesoscale meteorology model. The inclusion of a chemistry module (WRF-Chem) allows transport simulations of chemical and aerosol species such as those observed during NASA's Arctic Research of the Composition of the Troposphere from Aircraft and Satellites (ARCTAS) in 2008. The ARCTAS summer deployment phase during June and July coincided with large boreal wildfires in Saskatchewan and Eastern Russia. One of the most important aspects of simulating wildfire plume transport is the height at which emissions are injected. WRF-Chem contains an integrated one-dimensional plume rise model to determine the appropriate injection layer. The plume rise model accounts for thermal buoyancy associated with fires and local atmospheric stability. This paper describes a case study of a 10 day period during the Spring phase of ARCTAS. It compares results from the plume model against those of two more traditional injection methods: Injecting within the planetary boundary layer, and in a layer 3-5 km above ground level. Fire locations are satellite derived from the GOES Wildfire Automated Biomass Burning Algorithm (WF_ABBA) and the MODIS thermal hotspot detection. Two methods for preprocessing these fire data are compared: The prep_chem_sources method included with WRF-Chem, and the Naval Research Laboratory's Fire Locating and Monitoring of Burning Emissions (FLAMBE). Results from the simulations are compared with satellite-derived products from the AIRS, MISR and CALIOP sensors. When FLAMBE provides input to the 1-D plume rise model, the resulting injection heights exhibit the best agreement with satellite-observed injection heights. The FLAMBE-derived heights are more realistic than those utilizing prep_chem_sources. Conversely, when the planetary boundary layer or the 3-5 km a.g.l. layer were filled with emissions, the resulting injection heights exhibit less agreement with observed plume heights

Hole injection enhancement in organic light emitting devices using plasma treated graphene oxide

Energy Technology Data Exchange (ETDEWEB)

Jesuraj, P. Justin; Parameshwari, R. [Centre for Nanoscience and Nanotechnology, School of Physics, Bharathidasan University, Tiruchirappalli, 620 024, Tamil Nadu (India); Kanthasamy, K.; Koch, J. [Institut für Festkörperphysik, ATMOS, Appelstr. 2, D-30167, Hannover (Germany); Pfnür, H. [Institut für Festkörperphysik, ATMOS, Appelstr. 2, D-30167, Hannover (Germany); Laboratorium für Nano- und Quantene$ngineering, Schneiderberg 30, D-30167, Hannover (Germany); Jeganathan, K., E-mail: kjeganathan@yahoo.com [Centre for Nanoscience and Nanotechnology, School of Physics, Bharathidasan University, Tiruchirappalli, 620 024, Tamil Nadu (India)

2017-03-01

Graphical abstract: Plasma treated Graphene oxide for hole injection enhancement in OLEDs. - Highlights: • Oxygen (O{sub 2}) and hydrogen (H{sub 2}) plasma exposed graphene oxide (GO) sheets have been demonstrated as hole buffer layers in OLEDs. • O{sub 2} plasma exposure induces assimilation of oxygen contents in GO lattice resulting in improved work function that reduced the hole injection barrier further. Whereas, H{sub 2} plasma contrastingly reduced the GO by excluding oxygen which ensuing lower work function. • X-ray photoelectron spectroscopy and ultraviolet photoelectron spectroscopy investigations reveal the capricious amount of oxygen in GO lattice and its corresponding work function variations. • GO and O{sub 2} plasma treated GO significantly improves the current efficiency of OLEDs more than one order with notable reduction in turn on voltage. - Abstract: The hole injection layer (HIL) with high work function (WF) is desirable to reduce the injection barrier between anode and hole transport layer in organic light emitting devices (OLED). Here, we report a novel approach to tune the WF of graphene oxide (GO) using oxygen and hydrogen plasma treatment and its hole injection properties in OLEDs. The mild exposure of oxygen plasma on GO (O{sub 2}-GO) significantly reduces the injection barrier by increasing the WF of anode (4.98 eV) through expansion of C−O bonds. In contrast, the hole injection barrier was drastically increased for hydrogen plasma treated GO (H{sub 2}-GO) layers as the WF is lowered by the contraction of C−O bond. By employing active O{sub 2}-GO as HIL in OLEDs found to exhibit superior current efficiency of 4.2 cd/A as compared to 3.3 cd/A for pristine GO. Further, the high injection efficiency of O{sub 2}-GO infused hole only device can be attributed to the improved energy level matching. Ultraviolet and X-ray photoelectron spectroscopy were used to correlate the WF of HIL infused anode towards the enhanced performance of

Charge generation layers for solution processed tandem organic light emitting diodes with regular device architecture.

Science.gov (United States)

Höfle, Stefan; Bernhard, Christoph; Bruns, Michael; Kübel, Christian; Scherer, Torsten; Lemmer, Uli; Colsmann, Alexander

2015-04-22

Tandem organic light emitting diodes (OLEDs) utilizing fluorescent polymers in both sub-OLEDs and a regular device architecture were fabricated from solution, and their structure and performance characterized. The charge carrier generation layer comprised a zinc oxide layer, modified by a polyethylenimine interface dipole, for electron injection and either MoO3, WO3, or VOx for hole injection into the adjacent sub-OLEDs. ToF-SIMS investigations and STEM-EDX mapping verified the distinct functional layers throughout the layer stack. At a given device current density, the current efficiencies of both sub-OLEDs add up to a maximum of 25 cd/A, indicating a properly working tandem OLED.

Steady flow in a porous layer subjected to a stream uniformly injecting from a plane; Ichiyo ni men kara fukidasu nagare ni sarasareta takoshitsu sonai no teijo nagare

Energy Technology Data Exchange (ETDEWEB)

Hasegawa, E; Horiguchi, Y; Kitazawa, K [Keio University, Tokyo (Japan). Faculty of Science and Technology

1997-08-25

A steady flow in an non-deformable porous layer subjected to a fluid stream is studied analytically and numerically. One side of the layer of sponge is bounded by a solid wall and the other by a layer of fluid. The fluid is injected uniformly from a plane, through which the fluid can pass, set up parallel to the sponge layer. The flow in the sponge layer is assumed to be governed by Darcy`s law. The problem considered is solved in terms of a similarity solution. The equations governing the fluid flows in both the porous layer and the fluid layer are reduced to a system of the ordinary differential equations. These equations are solved analytically for three cases ideal fluid flow, low Reynolds number flow and high Reynolds number flow. On the other hand, these equations are solved numerically for the general case by using the finite difference method. The distributions of the velocity and the pressure in both layers are found for various parameters. In particular, the speed which the fluid intrudes into the sponge layer due to the injection of the stream from the plane is found to be a function of dimensionless parameters. To find this speed is essential to the understanding of porous material. 15 refs., 9 figs.

Cell turnover in the odontogenic organ of the rat incisor as visualized by graphic reconstructions following a single injection of 3H-thymidine.

Science.gov (United States)

Smith, C E

1980-07-01

Turnover of cells within the odontogenic organ was studied in three dimensions by preparing serial sections of incisors from young male rats killed at various times following a single intraperitoneal injection of 1 muCi/g body weight of 3H-thymidine. Radioautographs showed that at 1 hour after injection labeled cells were present in all cell layers throughout the entire depth of the odontogenic organ. They were encountered frequently within the inner dental epithelium and stratum intermedium but appeared less abundant within the stellate reticulum and outer dental epithelium. With time, the frequency of labeled cells in each layer declined progressively, and more rapidly at the anterior and labial side of the odontogenic organ than toward its posterior and lingual side. Hence labeled cells were observed over the longest time interval in regions where cell layers were in closest proximity to the opening of the apical foramen, that is, near the apical and cervical loops. By 32 days after injection, numerous labeled cells could still be identified within the outer dental epithelium and stellate reticulum near the apical loop (bulbous part of the odontogenic organ) and the outer dental epithelium near the cervical loops ("U"-shaped part of the odontogenic organ). These findings support the hypothesis that cells originate within the bulbous part of the odontogenic organ and migrate anteriorly through the "U"-shaped and root sheath parts of the odontogenic organ during renewal of the incisor. It appears that individual stem cell compartments may be maintained for surface (outer/inner dental epithelium) and intermediate layers (stellate reticulum/stratum intermedium) in the odontogenic epithelium.

Enhancing Carrier Injection Using Graded Superlattice Electron Blocking Layer for UVB Light-Emitting Diodes

KAUST Repository

Janjua, Bilal

2014-12-01

We have studied enhanced carrier injection by having an electron blocking layer (EBL) based on a graded superlattice (SL) design. Here, we examine, using a selfconsistent 6 × 6 k.p method, the energy band alignment diagrams under equilibrium and forward bias conditions while also considering carrier distribution and recombination rates (Shockley-Read-Hall, Auger, and radiative recombination rates). The graded SL is based on AlxGa1-xN (larger bandgap) Al0:5Ga0:5N (smaller bandgap) SL, where x is changed from 0.8 to 0.56 in steps of 0.06. Graded SL was found to be effective in reducing electron leakage and enhancing hole injection into the active region. Due to our band engineering scheme for EBL, four orders-of-magnitude enhancement were observed in the direct recombination rate, as compared with the conventional bulk EBL consisting of Al0:8Ga0:2N. An increase in the spatial overlap of carrier wavefunction was obtained due to polarization-induced band bending in the active region. An efficient single quantum-well ultraviolet-B light-emitting diode was designed, which emits at 280 nm. This is the effective wavelength for water disinfection application, among others.

An investigation of methods for injecting emissions from boreal wildfires using WRF-Chem during ARCTAS

Directory of Open Access Journals (Sweden)

W. R. Sessions

2011-06-01

Full Text Available The Weather Research and Forecasting Model (WRF is considered a "next generation" mesoscale meteorology model. The inclusion of a chemistry module (WRF-Chem allows transport simulations of chemical and aerosol species such as those observed during NASA's Arctic Research of the Composition of the Troposphere from Aircraft and Satellites (ARCTAS in 2008. The ARCTAS summer deployment phase during June and July coincided with large boreal wildfires in Saskatchewan and Eastern Russia.

One of the most important aspects of simulating wildfire plume transport is the height at which emissions are injected. WRF-Chem contains an integrated one-dimensional plume rise model to determine the appropriate injection layer. The plume rise model accounts for thermal buoyancy associated with fires and local atmospheric stability. This paper describes a case study of a 10 day period during the Spring phase of ARCTAS. It compares results from the plume model against those of two more traditional injection methods: Injecting within the planetary boundary layer, and in a layer 3–5 km above ground level. Fire locations are satellite derived from the GOES Wildfire Automated Biomass Burning Algorithm (WF_ABBA and the MODIS thermal hotspot detection. Two methods for preprocessing these fire data are compared: The prep_chem_sources method included with WRF-Chem, and the Naval Research Laboratory's Fire Locating and Monitoring of Burning Emissions (FLAMBE. Results from the simulations are compared with satellite-derived products from the AIRS, MISR and CALIOP sensors.

When FLAMBE provides input to the 1-D plume rise model, the resulting injection heights exhibit the best agreement with satellite-observed injection heights. The FLAMBE-derived heights are more realistic than those utilizing prep_chem_sources. Conversely, when the planetary boundary layer or the 3–5 km a.g.l. layer were filled with emissions, the resulting injection heights exhibit less

Layer-dependent band alignment and work function of few-layer phosphorene.

Science.gov (United States)

Cai, Yongqing; Zhang, Gang; Zhang, Yong-Wei

2014-10-20

Using first-principles calculations, we study the electronic properties of few-layer phosphorene focusing on layer-dependent behavior of band gap, work function band alignment and carrier effective mass. It is found that few-layer phosphorene shows a robust direct band gap character, and its band gap decreases with the number of layers following a power law. The work function decreases rapidly from monolayer (5.16 eV) to trilayer (4.56 eV), and then slowly upon further increasing the layer number. Compared to monolayer phosphorene, there is a drastic decrease of hole effective mass along the ridge (zigzag) direction for bilayer phosphorene, indicating a strong interlayer coupling and screening effect. Our study suggests that 1). Few-layer phosphorene with a layer-dependent band gap and a robust direct band gap character is promising for efficient solar energy harvest. 2). Few-layer phosphorene outperforms monolayer counterpart in terms of a lighter carrier effective mass, a higher carrier density and a weaker scattering due to enhanced screening. 3). The layer-dependent band edges and work functions of few-layer phosphorene allow for modification of Schottky barrier with enhanced carrier injection efficiency. It is expected that few-layer phosphorene will present abundant opportunities for a plethora of new electronic applications.

Influence of hypodermic needle dimensions on subcutaneous injection delivery - a pig study of injection deposition evaluated by CT scanning, histology, and backflow

DEFF Research Database (Denmark)

Ann Praestmark Juul, Kezia; Bengtsson, Henrik; Eyving, Bente

2012-01-01

, little is known about local drug delivery in relation to needle length and thickness. This study aimed to compare deposition depth and backflow from three hypodermic needles of 3 mm 34G (0.19 mm), 5 mm 32G (0.23 mm), and 8 mm 30G (0.30 mm) in length and thickness. METHODS: Ex vivo experiments were......BACKGROUND: Thinner and shorter needles for subcutaneous administration are continuously developed. Previous studies have shown that a thinner needle causes fewer occurrences of painful needle insertions and that a shorter needle decreases the occurrence of painful intramuscular injections. However...... depth, the bulk of the injection was in the subcutaneous tissue and did not propagate from subcutis into dermis. With the 8 mm 30G needle all injections apart from one intramuscular injection were located in the subcutaneous layer. The volume depositions peaked in 4-5 mm depth for the 3 mm 34G needle...

Silicon based light emitter utilizing tunnel injection of excess carriers via MIS structure

Energy Technology Data Exchange (ETDEWEB)

Arguirov, Tzanimir; Kittler, Martin [IHP - Innovations for High Performance Microelectronics, Im Technologiepark 25, 15236 Frankfurt (Oder) (Germany); IHP/BTU Joint Lab BTU Cottbus, Konrad-Wachsmann-Allee 1, 03013 Cottbus (Germany); Wenger, Christian; Lukosius, Mindaugas [IHP - Innovations for High Performance Microelectronics, Im Technologiepark 25, 15236 Frankfurt (Oder) (Germany); Mchedlidze, Teimuraz [IHP/BTU Joint Lab BTU Cottbus, Konrad-Wachsmann-Allee 1, 03013 Cottbus (Germany); Reiche, Manfred [Max-Planck-Institut fuer Mikrostrukturphysik, Weinberg 2, 06120 Halle (Germany)

2011-04-15

We report on electro-luminescence from metal-insulator-semiconductor diodes (MISLED). MISLEDs prepared on silicon with HfO2 layers of different thicknesses were investigated and their properties compared with such prepared by using SiO2 insulator layer. The role of the insulator layer was studied in view of the efficiency of the band-to-band radiation from silicon. We show that the luminescence efficiency depends on the dielectric constant of the insulator as well as on its ability to conduct carriers by tunnelling. Efficiency enhancement of 3.3 times was detected when the SiO{sub 2} insulator was substituted by HfO{sub 2} in the MIS emitter. Optimal injection current exists, which leads to a maximal efficiency of the luminescence. The optimal current depends strongly on the thickness of the oxide. We relate the existence of an optimal current with the depth at which the injected minority carriers recombine radiatively. Thus the electric field in the semiconductor and the surface recombination are the factors determining the optimal injection (copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

Spin injection and magnetoresistance in MoS2-based tunnel junctions using Fe3Si Heusler alloy electrodes.

Science.gov (United States)

Rotjanapittayakul, Worasak; Pijitrojana, Wanchai; Archer, Thomas; Sanvito, Stefano; Prasongkit, Jariyanee

2018-03-19

Recently magnetic tunnel junctions using two-dimensional MoS 2 as nonmagnetic spacer have been fabricated, although their magnetoresistance has been reported to be quite low. This may be attributed to the use of permalloy electrodes, injecting current with a relatively small spin polarization. Here we evaluate the performance of MoS 2 -based tunnel junctions using Fe 3 Si Heusler alloy electrodes. Density functional theory and the non-equilibrium Green's function method are used to investigate the spin injection efficiency (SIE) and the magnetoresistance (MR) ratio as a function of the MoS 2 thickness. We find a maximum MR of ~300% with a SIE of about 80% for spacers comprising between 3 and 5 MoS 2 monolayers. Most importantly, both the SIE and the MR remain robust at finite bias, namely MR > 100% and SIE > 50% at 0.7 V. Our proposed materials stack thus demonstrates the possibility of developing a new generation of performing magnetic tunnel junctions with layered two-dimensional compounds as spacers.

Effect of Coercive Voltage and Charge Injection on Performance of a Ferroelectric-Gate Thin-Film Transistor

Directory of Open Access Journals (Sweden)

P. T. Tue

2013-01-01

Full Text Available We adopted a lanthanum oxide capping layer between semiconducting channel and insulator layers for fabrication of a ferroelectric-gate thin-film transistor memory (FGT which uses solution-processed indium-tin-oxide (ITO and lead-zirconium-titanate (PZT film as a channel layer and a gate insulator, respectively. Good transistor characteristics such as a high “on/off” current ratio, high channel mobility, and a large memory window of 108, 15.0 cm2 V−1 s−1, and 3.5 V were obtained, respectively. Further, a correlation between effective coercive voltage, charge injection effect, and FGT’s memory window was investigated. It is found that the charge injection from the channel to the insulator layer, which occurs at a high electric field, dramatically influences the memory window. The memory window’s enhancement can be explained by a dual effect of the capping layer: (1 a reduction of the charge injection and (2 an increase of effective coercive voltage dropped on the insulator.

Passivation Layers for Indoor Solar Cells at Low Irradiation Intensities

OpenAIRE

Rühle, K.; Rauer, M.; Rüdiger, M.; Giesecke, J.; Niewelt, T.; Schmiga, C.; Glunz, S.W.; Kasemann, M.

2012-01-01

The passivation mechanisms and qualities of Al2O3, SiNx, SiO2 and a-Si:H(i) on p- and n-type silicon are investigated by quasi-steady-state photoluminescence measurements. This technique allows effective lifetime measurements in an extremely large injection range between 1010 cm-3 and 1017 cm-3. The measurements are discussed focusing on injections below 1012 cm-3 in order to determine the most effective passivation layer for solar cells arranged for indoor applications. Fixed negative charge...

RBS analysis of electrochromic layers

Energy Technology Data Exchange (ETDEWEB)

Green, D.C.; Bell, J.M. [University of Technology, Sydney, NSW (Australia); Kenny, M.J.; Wielunski, L.S. [Commonwealth Scientific and Industrial Research Organisation (CSIRO), Lindfield, NSW (Australia). Div. of Applied Physics

1993-12-31

Tungsten oxide thin films produced by dip-coating from tungsten alkoxide solutions are of interest for their application in large area switchable windows. The application consists of a layer of electrochromic tungsten oxide (W0{sub 3}) on indium tin oxide (ITO) coated glass in contact with a complementary structure. Electrochromic devices are switchable between states of high and low transparency by the application of a small voltage. The mechanism relies on the dual injection of ions and electrons into the W0{sub 3} layer from adjacent layers in the device. Electrochromic tungsten oxide can be deposited using standard techniques (eg. sputtering and evaporation) but also using sol-gel deposition. Sol-gel processing has an advantage over conventional preparation techniques because of the simplicity of the equipment. The scaling up to large area coatings is also feasible. RBS and forward recoil has been used to obtain profiles for individual elements in the structure of electrochromic films. 3 refs., 3 figs.

RBS analysis of electrochromic layers

Energy Technology Data Exchange (ETDEWEB)

Green, D C; Bell, J M [University of Technology, Sydney, NSW (Australia); Kenny, M J; Wielunski, L S [Commonwealth Scientific and Industrial Research Organisation (CSIRO), Lindfield, NSW (Australia). Div. of Applied Physics

1994-12-31

Tungsten oxide thin films produced by dip-coating from tungsten alkoxide solutions are of interest for their application in large area switchable windows. The application consists of a layer of electrochromic tungsten oxide (W0{sub 3}) on indium tin oxide (ITO) coated glass in contact with a complementary structure. Electrochromic devices are switchable between states of high and low transparency by the application of a small voltage. The mechanism relies on the dual injection of ions and electrons into the W0{sub 3} layer from adjacent layers in the device. Electrochromic tungsten oxide can be deposited using standard techniques (eg. sputtering and evaporation) but also using sol-gel deposition. Sol-gel processing has an advantage over conventional preparation techniques because of the simplicity of the equipment. The scaling up to large area coatings is also feasible. RBS and forward recoil has been used to obtain profiles for individual elements in the structure of electrochromic films. 3 refs., 3 figs.

Influence of Pentacene Interface Layer in ITO/α-NPD/Alq3/Al Organic Light Emitting Diodes by Time-Resolved Electric-Field-Induced Optical Second-Harmonic Generation Measurement.

Science.gov (United States)

Oda, Yoshiaki; Sadakata, Atsuo; Taguchi, Dai; Manaka, Takaaki; Iwamoto, Mitsumasa

2016-04-01

By using I-V, EL-V, displacement current measurement (DCM) and time-resolved electric-field-induced optical second-harmonic generation (TR-EFISHG) measurement, we studied the influence of interface pentacene layer inserted between ITO and a-NPD layers in ITO/α-NPD/Alq3/Al OLEDs. All experiments were carried out for the OLEDs with and without a pentacene interface layer. The I-V and EL-V measurements showed the decrease of operating voltage of EL, the DCM showed the lowering of inception voltage of carrier injection by inserting a pentacene interface layer. The TR-EFISHG measurement showed the faster accumulation of holes at the interface between the a-NPD and Alq3 layers, which resulted in the relaxation of electric field of a-NPD layer accomplished by the increase of the conductivity and the increase of the electric field in the Alq3 layer. We conclude that TR-EFISHG measurement is helpful for understanding I-V and EL-V characteristics, and can be combined with other methods to give significant information which are impacted by the interface layer.

Spin transport in two-layer-CVD-hBN/graphene/hBN heterostructures

Science.gov (United States)

Gurram, M.; Omar, S.; Zihlmann, S.; Makk, P.; Li, Q. C.; Zhang, Y. F.; Schönenberger, C.; van Wees, B. J.

2018-01-01

We study room-temperature spin transport in graphene devices encapsulated between a layer-by-layer-stacked two-layer-thick chemical vapor deposition (CVD) grown hexagonal boron nitride (hBN) tunnel barrier, and a few-layer-thick exfoliated-hBN substrate. We find mobilities and spin-relaxation times comparable to that of SiO2 substrate-based graphene devices, and we obtain a similar order of magnitude of spin relaxation rates for both the Elliott-Yafet and D'Yakonov-Perel' mechanisms. The behavior of ferromagnet/two-layer-CVD-hBN/graphene/hBN contacts ranges from transparent to tunneling due to inhomogeneities in the CVD-hBN barriers. Surprisingly, we find both positive and negative spin polarizations for high-resistance two-layer-CVD-hBN barrier contacts with respect to the low-resistance contacts. Furthermore, we find that the differential spin-injection polarization of the high-resistance contacts can be modulated by dc bias from -0.3 to +0.3 V with no change in its sign, while its magnitude increases at higher negative bias. These features point to the distinctive spin-injection nature of the two-layer-CVD-hBN compared to the bilayer-exfoliated-hBN tunnel barriers.

Nicolau Syndrome after Intramuscular Injection of Non-Steroidal Anti-Inflammatory Drugs (NSAID

Directory of Open Access Journals (Sweden)

Mehmet Dadaci

2015-01-01

Full Text Available Nicolau syndrome is a rare complication of intramuscular injection that leads to local ischemic necrosis of the skin and adipose tissue. In this paper, we discuss etiologies, risk factors, and treatment options for gluteal Nicolau syndrome referring to patients treated in our hospital. Our study includes 17 women who visited our clinic with symptoms of gluteal necrosis secondary to intramuscular injection. The following variables were taken into account: injection site, drug administered, frequency of injections, the person who administered the injections, needle size, and needle tip color. Magnetic resonance images obtained in the aftermath of intramuscular injection application were carefully analyzed for presence of necrosis, cyst formation and the thickness of the gluteal fat tissue layer. Drugs that had been received in intramuscular injection were exclusively non-steroidal anti-inflammatory drugs. Mean patient BMI was 41.8 (all patients were considered as obese, and mean gluteal fat thickness was 54 mm. Standard length of needles (3.8 cm had been used in procedures. The wounds were treated with primary closure in 11 patients and with local flap therapy in 6 patients. The observed necrosis was a consequence of misplaced gluteal injection, where drugs were injected into the adipose tissue instead of the muscle due to the extreme thickness of the fat layer, on one hand, and the inappropriate length of standard needles, on the other hand. Intramuscular injection should be avoided in obese patients whenever possible: if it is necessary, proper injection technique should be used.

Atomic layer deposition of epitaxial layers of anatase on strontium titanate single crystals: Morphological and photoelectrochemical characterization

Energy Technology Data Exchange (ETDEWEB)

Kraus, Theodore J.; Nepomnyashchii, Alexander B.; Parkinson, B. A., E-mail: bparkin1@uwyo.edu [Department of Chemistry, School of Energy Resources, University of Wyoming, Laramie, Wyoming 82071 (United States)

2015-01-15

Atomic layer deposition was used to grow epitaxial layers of anatase (001) TiO{sub 2} on the surface of SrTiO{sub 3} (100) crystals with a 3% lattice mismatch. The epilayers grow as anatase (001) as confirmed by x-ray diffraction. Atomic force microscope images of deposited films showed epitaxial layer-by-layer growth up to about 10 nm, whereas thicker films, of up to 32 nm, revealed the formation of 2–5 nm anatase nanocrystallites oriented in the (001) direction. The anatase epilayers were used as substrates for dye sensitization. The as received strontium titanate crystal was not sensitized with a ruthenium-based dye (N3) or a thiacyanine dye (G15); however, photocurrent from excited state electron injection from these dyes was observed when adsorbed on the anatase epilayers. These results show that highly ordered anatase surfaces can be grown on an easily obtained substrate crystal.

Observation of hole injection boost via two parallel paths in Pentacene thin-film transistors by employing Pentacene: 4, 4″-tris(3-methylphenylphenylamino triphenylamine: MoO3 buffer layer

Directory of Open Access Journals (Sweden)

Pingrui Yan

2014-11-01

Full Text Available Pentacene organic thin-film transistors (OTFTs were prepared by introducing 4, 4″-tris(3-methylphenylphenylamino triphenylamine (m-MTDATA: MoO3, Pentacene: MoO3, and Pentacene: m-MTDATA: MoO3 as buffer layers. These OTFTs all showed significant performance improvement comparing to the reference device. Significantly, we observe that the device employing Pentacene: m-MTDATA: MoO3 buffer layer can both take advantage of charge transfer complexes formed in the m-MTDATA: MoO3 device and suitable energy level alignment existed in the Pentacene: MoO3 device. These two parallel paths led to a high mobility, low threshold voltage, and contact resistance of 0.72 cm2/V s, −13.4 V, and 0.83 kΩ at Vds = − 100 V. This work enriches the understanding of MoO3 doped organic materials for applications in OTFTs.

Polyelectrolyte Layer-by-Layer Assembly on Organic Electrochemical Transistors

KAUST Repository

Pappa, Anna-Maria

2017-03-06

Oppositely charged polyelectrolyte multilayers (PEMs) were built up in a layer-by-layer (LbL) assembly on top of the conducting polymer channel of an organic electrochemical transistor (OECT), aiming to combine the advantages of well-established PEMs with a high performance electronic transducer. The multilayered film is a model system to investigate the impact of biofunctionalization on the operation of OECTs comprising a poly(3,4-ethylenedioxythiophene) polystyrenesulfonate (PEDOT:PSS) film as the electrically active layer. Understanding the mechanism of ion injection into the channel that is in direct contact with charged polymer films provides useful insights for novel biosensing applications such as nucleic acid sensing. Moreover, LbL is demonstrated to be a versatile electrode modification tool enabling tailored surface features in terms of thickness, softness, roughness, and charge. LbL assemblies built up on top of conducting polymers will aid the design of new bioelectronic platforms for drug delivery, tissue engineering, and medical diagnostics.

Polyelectrolyte Layer-by-Layer Assembly on Organic Electrochemical Transistors

KAUST Repository

Pappa, Anna-Maria; Inal, Sahika; Roy, Kirsty; Zhang, Yi; Pitsalidis, Charalampos; Hama, Adel; Pas, Jolien; Malliaras, George G.; Owens, Roisin M.

2017-01-01

Oppositely charged polyelectrolyte multilayers (PEMs) were built up in a layer-by-layer (LbL) assembly on top of the conducting polymer channel of an organic electrochemical transistor (OECT), aiming to combine the advantages of well-established PEMs with a high performance electronic transducer. The multilayered film is a model system to investigate the impact of biofunctionalization on the operation of OECTs comprising a poly(3,4-ethylenedioxythiophene) polystyrenesulfonate (PEDOT:PSS) film as the electrically active layer. Understanding the mechanism of ion injection into the channel that is in direct contact with charged polymer films provides useful insights for novel biosensing applications such as nucleic acid sensing. Moreover, LbL is demonstrated to be a versatile electrode modification tool enabling tailored surface features in terms of thickness, softness, roughness, and charge. LbL assemblies built up on top of conducting polymers will aid the design of new bioelectronic platforms for drug delivery, tissue engineering, and medical diagnostics.

Optimal thickness of hole transport layer in doped OLEDs

Energy Technology Data Exchange (ETDEWEB)

Zhou, Y.C.; Zhou, J.; Zhao, J.M.; Zhang, S.T.; Zhan, Y.Q.; Wang, X.Z.; Wu, Y.; Ding, X.M.; Hou, X.Y. [Fudan University, Surface Physics Laboratory (National Key Laboratory), Shanghai (China)

2006-06-15

Current-voltage (I-V) and electroluminescence (EL) characteristics of organic light-emitting devices with N,N'-Di-[(1-naphthalenyl)-N,N'-diphenyl]-(1,1'-biphenyl)-4,4'-diamine (NPB) of various thicknesses as the hole transport layer, and tris(8-hydroxyquinoline)aluminum (Alq{sub 3}) selectively doped with 4-(dicyanomethylene)-2-methyl-6-(p-dimethylaminostyryl)-4H-pyran (DCM) as the electron transport layer, have been investigated. A trapped charge induced band bend model is proposed to explain the I-V characteristics. It is suggested that space charge changes the injection barrier and therefore influences the electron injection process in addition to the carrier transport process. Enhanced external quantum efficiency of the devices due to the electron blocking effect of an inserted NPB layer is observed. The optimal thickness of the NPB layer is experimentally determined to be 12{+-}3 nm in doped devices, a value different from that for undoped devices, which is attributed to the electron trap effect of DCM molecules. This is consistent with the result that the proportion of Alq{sub 3} luminescence in the total electroluminescence (EL) spectra increases with NPB thickness up to 12 nm under a fixed bias. (orig.)

Role of the polymeric hole injection layer on the efficiency and stability of organic light emitting diodes with small molecular emitters

International Nuclear Information System (INIS)

Chin, Byung Doo

2008-01-01

In this paper, an improvement in the properties of the small molecular organic light emitting diode (OLED) upon application of a polymeric hole injection layer (HIL) was reported. The luminous efficiency, operating voltage and lifetime of devices with dye-doped small molecule emitters (fluorescent and phosphorescent) were found to be sensitive to the HIL/hole transport layer (HTL) combination used, where the improved injection and brightness was shown at the hole cascading structure and the longer lifetime behaviour was obtained at the hole-trapping structure. Use of a polymeric HIL significantly increased the luminous current efficiency and lifetime for both fluorescent blue and phosphorescent green/red light emitters. The polymeric HIL was effective in terms of the driving characteristics of phosphorescent OLED, since it provides higher brightness behaviour at lower current density. The apparent shade of the pixel image at light emission, which will probably induce degradation at the pixel wall interface, will be suppressed by the use of polymeric HIL. In spite of the ambiguity in the formation of such shaded pixels and their influence at the decay of OLED, intrinsic stability of polymeric HIL/anode would be advantageous for stable storage and operation of devices.

Naloxone injections into CA3 disrupt pattern completion associated with relapse from cocaine seeking

Science.gov (United States)

Kirk, Ryan A.; Clark, Jascha K.; Moore, Angela; Keefe, Kristen

2016-01-01

The goal of the present research was to assess the degree to which a pattern completion process operates in cue-induced relapse to cocaine-seeking behavior. Using a novel cue-preference version of the place preference task, rats were administered cocaine or saline, which resulted in a preference for the cocaine-paired cues. After 21 days of abstinence and prior to the preference test, for one group, PBS or naloxone was injected into the CA3 subregion of the hippocampus and for a second group, saline or naloxone was injected systemically. The results indicated that infusions of naloxone into CA3 or systemic injections produced a marked disruption for one and two cues, but had minimal disruptive effect for three or four cues, suggesting that naloxone injections disrupt CA3 function and trigger a deficit in a pattern completion process. Thus, it appears that cue-based activation of the dorsal CA3 might be a critical trigger via a pattern completion process. Based on additional analyses it appears that there is a disruption primarily for object touches for one cue naloxone injections into the CA3 or systemic injections, but no effect on time (spatial context). PMID:26815290

SAW propagation characteristics of TeO3/3C-SiC/LiNbO3 layered structure

Science.gov (United States)

Soni, Namrata D.

2018-04-01

Surface acoustic wave (SAW) devices based on Lithium Niobate (LiNbO3) single crystal are advantageous because of its high SAW phase velocity, electromechanical coupling coefficient and cost effectiveness. In the present work a new multi-layered TeO3/3C-SiC/128° Y-X LiNbO3 SAW device has been proposed. SAW propagation properties such as phase velocity, coupling coefficient and temperature coefficient of delay (TCD) of the TeO3/SiC/128° Y-X LiNbO3 multi layered structure is examined using theoretical calculations. It is found that the integration of 0.09λ thick 3C-SiC over layer on 128° Y-X LiNbO3 increases its electromechanical coupling coefficient from 5.3% to 9.77% and SAW velocity from 3800 ms‑1 to 4394 ms‑1. The SiC/128° Y-X LiNbO3 bilayer SAW structure exhibits a high positive TCD value. A temperature stable layered SAW device could be obtained with introduction of 0.007λ TeO3 over layer on SiC/128° Y-X LiNbO3 bilayer structure without sacrificing the efficiency of the device. The proposed TeO3/3C-SiC/128° Y-X LiNbO3 multi-layered SAW structure is found to be cost effective, efficient, temperature stable and suitable for high frequency application in harsh environment.

MgO by injection CVD

International Nuclear Information System (INIS)

Abrutis, A.; Kubilius, V.; Teiserkis, A.; Bigelyte, V.; Vengalis, B.; Jukna, A.; Butkute, R.

1997-01-01

Epitaxial YBa 2 Cu 3 O 7 layers with 45 in-plane orientation have been grown by injection CVD on MgO substrates polished off-axis to within 1.4-1.9 of the [100] direction. This new single-source CVD process is based on computer-controlled injection of precise microdoses of a metal-organic precursor solution into a CVD reactor. A wide range of solution compositions was tested to investigate compositional effects on phase purity, surface morphology, texturing and superconducting properties of the prepared films. The highest quality films with pure 45 texture had a smooth surface, zero resistance T c (R=0) of 88-89 K, and critical current density J c (77 K) above 10 6 A/cm 2 . (orig.) and critical current density J c (77 K) above 10 6 A/cm 2 . (orig.)

Air Layer Drag Reduction

Science.gov (United States)

Ceccio, Steven; Elbing, Brian; Winkel, Eric; Dowling, David; Perlin, Marc

2008-11-01

A set of experiments have been conducted at the US Navy's Large Cavitation Channel to investigate skin-friction drag reduction with the injection of air into a high Reynolds number turbulent boundary layer. Testing was performed on a 12.9 m long flat-plate test model with the surface hydraulically smooth and fully rough at downstream-distance-based Reynolds numbers to 220 million and at speeds to 20 m/s. Local skin-friction, near-wall bulk void fraction, and near-wall bubble imaging were monitored along the length of the model. The instrument suite was used to access the requirements necessary to achieve air layer drag reduction (ALDR). Injection of air over a wide range of air fluxes showed that three drag reduction regimes exist when injecting air; (1) bubble drag reduction that has poor downstream persistence, (2) a transitional regime with a steep rise in drag reduction, and (3) ALDR regime where the drag reduction plateaus at 90% ± 10% over the entire model length with large void fractions in the near-wall region. These investigations revealed several requirements for ALDR including; sufficient volumetric air fluxes that increase approximately with the square of the free-stream speed, slightly higher air fluxes are needed when the surface tension is reduced, higher air fluxes are required for rough surfaces, and the formation of ALDR is sensitive to the inlet condition.

Analysis of radiochemical purity (RCP) of 99Tcm-MAG3 injection

International Nuclear Information System (INIS)

Huang Qingquan; Xia Zhenmin

1992-01-01

A two-system paper chromatographic method has been established for the determination of RCP of 99 Tc m -MAG 3 injection. R f -values of 99 Tc m -MAG 3 , 99 Tc m O 4 - and H-R- 99 Tc m (hydrolysis reduced 99 Tc m ) are 0.9, 0.8, 0.0 in system I, and 0.0, 0.4, 0.0 in system II respectively. The RCP and percentages of 99 Tc m O 4 - and H-R- 99 Tc m of 99 Tc m -MAG 3 injection have been determined with this method

The growth of InAsSb/InAsP strained-layer superlattices for use in infrared emitters

Energy Technology Data Exchange (ETDEWEB)

Biefeld, R.M.; Allerman, A.A.; Kurtz, S.R. [and others

1997-06-01

We describe the metal-organic chemical vapor deposition growth of InAsSb/InAsP strained-layer superlattice (SLS) active regions for use in mid-infrared emitters. These SLSs were grown at 500{degrees}C, and 200 torr in a horizontal quartz reactor using TMIn, TESb, AsH{sub 3},and PH{sub 3}. By changing the layer thickness and composition we have prepared structures with low temperature ({le}20K) photoluminescence wavelengths ranging from 3.2 to 4.4 {mu}m. Excellent performance was observed for an SLS LED and both optically pumped and electrically injected SLS lasers. An optically pumped, double heterostructure laser emitted at 3.86 {mu}m with a maximum operating temperature of 240 K and a characteristic temperature of 33 K. We have also made electrically injected lasers and LEDs utilizing a GaAsSb/InAs semi-metal injection scheme. The semi-metal injected, broadband LED emitted at 4 {mu}m with 80 {mu}W of power at 300K and 200 mA average current. The InAsSb/InAsP SLS injection laser emitted at 3.6 gm at 120 K.

Layer-by-layer deposition of nanostructured CsPbBr3 perovskite thin films

Science.gov (United States)

Reshetnikova, A. A.; Matyushkin, L. B.; Andronov, A. A.; Sokolov, V. S.; Aleksandrova, O. A.; Moshnikov, V. A.

2017-11-01

Layer-by-layer deposition of nanostructured perovskites cesium lead halide thin films is described. The method of deposition is based on alternate immersion of the substrate in the precursor solutions or colloidal solution of nanocrystals and methyl acetate/lead nitrate solution using the device for deposition of films by SILAR and dip-coating techniques. An example of obtaining a photosensitive structure based on nanostructures of ZnO nanowires and layers of CsBbBr3 nanocrystals is also shown.

3D MHD simulations of pellet injection and disruptions in tokamak plasmas

International Nuclear Information System (INIS)

Strauss, H.R.; Park, W.; Belova, E.; Fu, G.Y.; Sugiyama, L.E.

2001-01-01

Nonlinear MHD simulation results of pellet injection show that MHD forces can accelerate large pellets, injected on the high field side of a tokamak, to the plasma center. Magnetic reconnection can produce a reverse shear q profile. Ballooning instability caused by pellets is also reduced by high field side injection. Studies are also reported of the current quench phase of disruptions, which can cause 3D halo currents and runaway electrons. (author)

3D MHD simulations of pellet injection and disruptions in tokamak plasmas

International Nuclear Information System (INIS)

Strauss, H.R.; Park, W.; Belova, E.; Fu, G.Y.; Sugiyama, L.E.

1999-01-01

Nonlinear MHD simulation results of pellet injection show that MHD forces can accelerate large pellets, injected on the high field side of a tokamak, to the plasma center. Magnetic reconnection can produce a reverse shear q profile. Ballooning instability caused by pellets is also reduced by high field side injection. Studies are also reported of the current quench phase of disruptions, which can cause 3D halo currents and runaway electrons. (author)

Efficient, air-stable quantum dots light-emitting devices with MoO3 modifying the anode

International Nuclear Information System (INIS)

Meng, Xiangdong; Ji, Wenyu; Hua, Jie; Yu, Zhaoliang; Zhang, Yan; Li, Haibo; Zhao, Jialong

2013-01-01

In this work, we fabricated quantum dots light-emitting devices with hole-injection layer, molybdenum oxide (MoO 3 ) substituting for poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) which is hygroscopic and acidic and, therefore, a source of interface instability. A significant enhancement in luminance and current efficiency in MoO 3 -containing devices was observed. In addition, MoO 3 -containing devices were more stable in the air than those with PEDOT:PSS as the hole injection layer. The hole injection and transport of the devices were studied by the J–V characteristics of the hole-only devices. The excellent performance of the devices was principally a result of MoO 3 possessing lower injection barrier for the hole and better stability than PEDOT:PSS. -- Highlights: • We fabricated QD-LEDs with MoO 3 substituting for PEDOT:PSS as hole-injection layer. • A enhancement in luminance and efficiency in MoO 3 -containing device was observed. • The enhancement was originated from the stability and easy hole injection of MoO 3

Study on a corrosion products behavior with zinc injection in PWR primary circuit based on the crud investigation in actual plant

International Nuclear Information System (INIS)

Hisamune Kenji; Nambu Tohru; Akutagawa Daisuke; Nagata Nobuaki; Shimizu, Yuichi; Nagamine, Kunitaka; Kogawa Noritaka

2012-09-01

Zinc injection into the reactor coolant of Pressurized Water Reactor (PWR) is one of the most effective techniques for removing radioactive cobalt from the chromite type spinel oxides in the inner layer of reactor coolant component surfaces. Many documents have reported that zinc injection applied plants have generally achieved positive dose rate reduction effects for the reactor coolant components and piping. Tsuruga Nuclear Power Plant unit 2 (hereafter Tsuruga unit 2) which applied zinc injection in 2005 has also achieved good dose reduction effects in most primary coolant piping. However, some piping without dose-rate reduction effects exist, it has come to an issue to plan radiation exposure reduction measures for the works around relevant piping. To plan a reasonable dose-rate reduction measures for respective components and piping in primary systems, it is considered necessary to understand the dose-rate reduction effects of zinc injection mechanically. Therefore, the surface oxides/deposits on piping and fuel cladding tubes with operational histories under zinc injection were investigated. As a result of the investigation, the changes in specific aspects of oxide layers and CRUDs are found as follow: - Owing to long-term zinc injection, deposits and oxides on the primary coolant piping are extremely reduced, the boundary between the outer oxide layer and the inner oxide layer become unclear with the thinning of the outer oxide layers. - At a Pressurizer Spray Piping, the dose-rate increases than before zinc injection. The oxide layers have the same 3-layer construction as before zinc injection, and the surface concentration of the radioactive cobalt is high. - At the fuel cladding tube surfaces, what is observed is the amount of metal nickel decrease and the chromium composition increase in the spinel type oxide From these results, it is suggested that, the oxide layers composed principally of zinc chromite spinel grow up on the pipe surface with zinc

Observation of hole injection boost via two parallel paths in Pentacene thin-film transistors by employing Pentacene: 4, 4″-tris(3-methylphenylphenylamino) triphenylamine: MoO{sub 3} buffer layer

Energy Technology Data Exchange (ETDEWEB)

Yan, Pingrui; Liu, Ziyang; Liu, Dongyang; Wang, Xuehui; Yue, Shouzhen; Zhao, Yi, E-mail: yizhao@jlu.edu.cn [State Key Laboratory on Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, Changchun 130012 (China); Zhang, Shiming, E-mail: zhangshimingjlu@gmail.com [State Key Laboratory on Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, Changchun 130012 (China); Département of Chemical Engineering, École Polytechnique de Montréal, Montréal, Québec H3C3J7 (Canada)

2014-11-01

Pentacene organic thin-film transistors (OTFTs) were prepared by introducing 4, 4″-tris(3-methylphenylphenylamino) triphenylamine (m-MTDATA): MoO{sub 3}, Pentacene: MoO{sub 3}, and Pentacene: m-MTDATA: MoO{sub 3} as buffer layers. These OTFTs all showed significant performance improvement comparing to the reference device. Significantly, we observe that the device employing Pentacene: m-MTDATA: MoO{sub 3} buffer layer can both take advantage of charge transfer complexes formed in the m-MTDATA: MoO{sub 3} device and suitable energy level alignment existed in the Pentacene: MoO{sub 3} device. These two parallel paths led to a high mobility, low threshold voltage, and contact resistance of 0.72 cm{sup 2}/V s, −13.4 V, and 0.83 kΩ at V{sub ds} = − 100 V. This work enriches the understanding of MoO{sub 3} doped organic materials for applications in OTFTs.

Nicolau Syndrome after Intramuscular Injection: 3 Cases

Directory of Open Access Journals (Sweden)

Seok-Kwun Kim

2012-05-01

Full Text Available Nicolau syndrome is a rare complication of intramuscular injection consisting of ischemic necrosis of skin, soft tissue, and muscular tissue that arises locoregionally. The characteristic pattern is pain around the injection site, developing into erythema, a livedoid dermatitis patch, and necrosis of the skin, subcutaneous fat, and muscle tissue. Three patients were injected with drugs (diclofenac sodium, ketoprofen, meperidine for pain relief. Three patients complained of pain, and a skin lesion was observed, after which necrosis developed on their buttocks. Each patient underwent debridement and coverage. The wound healed uneventfully. We report three cases of Nicolau syndrome in the buttocks following diclofenac intramuscular injection.

Improving Charge Injection in Organic Electronic Devices Using Self-Assembled Monolayers

Science.gov (United States)

Campbell, I. H.; Kress, J. D.; Martin, R. L.; Smith, D. L.; Barashkov, N. N.; Ferraris, J. P.

1997-03-01

Organic electronic devices consist of one or more insulating organic layers contacted by metallic conductors. The Schottky energy barrier between the metal and the organic material is determined by the work function of the metal contact as described in the ideal Schottky model. The magnitude of the metal/organic Schottky energy barrier controls charge injection from the metal into the organic layer. Previously, polar alkane-thiol based self-assembled monolayers (SAMs) were used to change the Schottky energy barrier between the metal and an organic film by more than 1 eV. In these SAMs, the large energy gap of the alkane molecules blocks charge injection into the organic layer despite the decrease of the Schottky energy barrier. Here, we demonstrate improved charge injection into the organic material by using conjugated self-assembled monolayers. The conjugated SAMs have modest energy gaps which allow improved charge injection into the organic layer. We present measurements of current-voltage characteristics and metal/organic Schottky energy barriers for device structures both with and without conjugated SAMs.

Impact of three-dimensional geometry on the performance of isolated electron-injection infrared detectors

Energy Technology Data Exchange (ETDEWEB)

Fathipour, Vala; Jang, Sung Jun; Nia, Iman Hassani; Mohseni, Hooman, E-mail: hmohseni@northwestern.edu [Bio-Inspired Sensors and Optoelectronics Laboratory, Northwestern University, 2145 Sheridan Rd, Evanston, Illinois 60208 (United States)

2015-01-12

We present a quantitative study of the influence of three-dimensional geometry of the isolated electron–injection detectors on their characteristics. Significant improvements in the device performance are obtained as a result of scaling the injector diameter with respect to the trapping/absorbing layer diameters. Devices with about ten times smaller injector area with respect to the trapping/absorbing layer areas show more than an order of magnitude lower dark current, as well as an order of magnitude higher optical gain compared with devices of same size injector and trapping/absorbing layer areas. Devices with 10 μm injector diameter and 30 μm trapping/absorbing layer diameter show an optical gain of ∼2000 at bias voltage of −3 V with a cutoff wavelength of 1700 nm. Analytical expressions are derived for the electron-injection detector optical gain to qualitatively explain the significance of scaling the injector with respect to the absorber.

Role of the inversion layer on the charge injection in silicon nanocrystal multilayered light emitting devices

Energy Technology Data Exchange (ETDEWEB)

Tondini, S. [Nanoscience Laboratory, Department of Physics, University of Trento, Via Sommarive 14, 38123 Trento (Italy); Dipartimento di Fisica, Informatica e Matematica, Università di Modena e Reggio Emilia, Via Campi 213/a, 41125 Modena (Italy); Pucker, G. [Advanced Photonics and Photovoltaics Group, Bruno Kessler Foundation, Via Sommarive 18, 38123 Trento (Italy); Pavesi, L. [Nanoscience Laboratory, Department of Physics, University of Trento, Via Sommarive 14, 38123 Trento (Italy)

2016-09-07

The role of the inversion layer on injection and recombination phenomena in light emitting diodes (LEDs) is here studied on a multilayer (ML) structure of silicon nanocrystals (Si-NCs) embedded in SiO{sub 2}. Two Si-NC LEDs, which are similar for the active material but different in the fabrication process, elucidate the role of the non-radiative recombination rates at the ML/substrate interface. By studying current- and capacitance-voltage characteristics as well as electroluminescence spectra and time-resolved electroluminescence under pulsed and alternating bias pumping scheme in both the devices, we are able to ascribe the different experimental results to an efficient or inefficient minority carrier (electron) supply by the p-type substrate in the metal oxide semiconductor LEDs.

Dynamic spin filtering at the Co/Alq3 interface mediated by weakly coupled second layer molecules

Science.gov (United States)

Droghetti, Andrea; Thielen, Philip; Rungger, Ivan; Haag, Norman; Großmann, Nicolas; Stöckl, Johannes; Stadtmüller, Benjamin; Aeschlimann, Martin; Sanvito, Stefano; Cinchetti, Mirko

2016-08-01

Spin filtering at organic-metal interfaces is often determined by the details of the interaction between the organic molecules and the inorganic magnets used as electrodes. Here we demonstrate a spin-filtering mechanism based on the dynamical spin relaxation of the long-living interface states formed by the magnet and weakly physisorbed molecules. We investigate the case of Alq3 on Co and, by combining two-photon photoemission experiments with electronic structure theory, show that the observed long-time spin-dependent electron dynamics is driven by molecules in the second organic layer. The interface states formed by physisorbed molecules are not spin-split, but acquire a spin-dependent lifetime, that is the result of dynamical spin-relaxation driven by the interaction with the Co substrate. Such spin-filtering mechanism has an important role in the injection of spin-polarized carriers across the interface and their successive hopping diffusion into successive molecular layers of molecular spintronics devices.

Tail state-assisted charge injection and recombination at the electron-collecting interface of P3HT:PCBM bulk-heterojunction polymer solar cells

Energy Technology Data Exchange (ETDEWEB)

Wang, He [Department of Chemical and Biological Engineering, Princeton University, Princeton, NJ 08544 (United States); Department of Electrical Engineering, Princeton University, Princeton, NJ 08544 (United States); Shah, Manas [Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States); Ganesan, Venkat [Department of Chemical Engineering, University of Texas at Austin, Austin, TX 78712 (United States); Chabinyc, Michael L. [Materials Department, University of California Santa Barbara, CA 93106 (United States); Loo, Yueh-Lin [Department of Chemical and Biological Engineering, Princeton University, Princeton, NJ 08544 (United States)

2012-12-15

The systematic insertion of thin films of P3HT and PCBM at the electron- and hole-collecting interfaces, respectively, in bulk-heterojunction polymer solar cells results in different extents of reduction in device characteristics, with the insertion of P3HT at the electron-collecting interface being less disruptive to the output currents compared to the insertion of PCBM at the hole-collecting interface. This asymmetry is attributed to differences in the tail state-assisted charge injection and recombination at the active layer-electrode interfaces. P3HT exhibits a higher density of tail states compared to PCBM; holes in these tail states can thus easily recombine with electrons at the electron-collection interface during device operation. This process is subsequently compensated by the injection of holes from the cathode into these tail states, which collectively enables net current flow through the polymer solar cell. The study presented herein thus provides a plausible explanation for why preferential segregation of P3HT to the cathode interface is inconsequential to device characteristics in P3HT:PCBM bulk-heterojunction solar cells. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Removal rate of [3H]hyaluronan injected subcutaneously in rabbits

International Nuclear Information System (INIS)

Reed, R.K.; Laurent, U.B.; Fraser, J.R.; Laurent, T.C.

1990-01-01

Hyaluronan is an important constituent of the extracellular matrix in skin, and recent studies suggest that there is a pool of easily removable (free) hyaluronan drained by lymph. The removal rate of free hyaluronan in skin was measured from the elimination of [ 3 H]hyaluronan, injected subcutaneously in 13 rabbits. The removal of radioactivity was determined from appearance of 3 H in plasma. During the first 24 h after injection, 10-87% of the tracer entered blood, less in injectates with high concentrations of hyaluronan. The removal was monoexponential with a half-life of 0.5-1 day when concentration of hyaluronan was 5 mg/ml or less. When hyaluronan concentration was 10 mg/ml or higher, the removal was slow for about 24 h and then became similar to that in experiments with low hyaluronan concentration. Free hyaluronan at physiological concentrations is thus turned over with the same rate as serum albumin, supporting the concept that hyaluronan is removed essentially by lymph flow to be degraded in lymph nodes and liver

Spin injection in epitaxial MnGa(111)/GaN(0001) heterostructures

Science.gov (United States)

Zube, Christian; Malindretos, Joerg; Watschke, Lars; Zamani, Reza R.; Disterheft, David; Ulbrich, Rainer G.; Rizzi, Angela; Iza, Michael; Keller, Stacia; DenBaars, Steven P.

2018-01-01

Ferromagnetic MnGa(111) layers were grown on GaN(0001) by molecular beam epitaxy. MnGa/GaN Schottky diodes with a doping level of around n = 7 × 1018 cm-3 were fabricated to achieve single step tunneling across the metal/semiconductor junction. Below the GaN layer, a thin InGaN quantum well served as optical spin detector ("spin-LED"). For electron spin injection from MnGa into GaN and subsequent spin transport through a 45 nm (70 nm) thick GaN layer, we observe a circular polarization of 0.3% (0.2%) in the electroluminescence at 80 K. Interface mixing, spin polarization losses during electrical transport in the GaN layer, and spin relaxation in the InGaN quantum well are discussed in relation with the low value of the optically detected spin polarization.

The compositional, structural, and magnetic properties of a Fe{sub 3}O{sub 4}/Ga{sub 2}O{sub 3}/GaN spin injecting hetero-structure grown by metal-organic chemical vapor deposition

Energy Technology Data Exchange (ETDEWEB)

Xu, Zhonghua; Huang, Shimin [Nanjing National Laboratory of Microstructures and School of Electronic Science and Engineering, Nanjing University, Nanjing 210023 (China); Tang, Kun, E-mail: ktang@nju.edu.cn [Nanjing National Laboratory of Microstructures and School of Electronic Science and Engineering, Nanjing University, Nanjing 210023 (China); Gu, Shulin, E-mail: slgu@nju.edu.cn [Nanjing National Laboratory of Microstructures and School of Electronic Science and Engineering, Nanjing University, Nanjing 210023 (China); Zhu, Shunming [Nanjing National Laboratory of Microstructures and School of Electronic Science and Engineering, Nanjing University, Nanjing 210023 (China); Ye, Jiandong [Nanjing National Laboratory of Microstructures and School of Electronic Science and Engineering, Nanjing University, Nanjing 210023 (China); Nanjing University Institute of Optoelectronics at Yangzhou, Yangzhou 225009 (China); Xu, Mingxiang [Department of Physics, Southeast University, Nanjing 210096 (China); Wang, Wei; Zheng, Youdou [Nanjing National Laboratory of Microstructures and School of Electronic Science and Engineering, Nanjing University, Nanjing 210023 (China)

2016-12-01

Highlights: • The Fe{sub 3}O{sub 4}/Ga{sub 2}O{sub 3}/GaN hetero-structure has been fabricated by MOCVD successfully. • The formation mechanism of different layers in sample was revealed in details. • The properties of the hetero-structure have been presented and discussed extensively. • The effect of Ga diffusion on the magnetic properties of Fe{sub 3}O{sub 4} film has been shown. - Abstract: In this article, the authors have designed and fabricated a Fe{sub 3}O{sub 4}/Ga{sub 2}O{sub 3}/GaN spin injecting hetero-structure by metal-organic chemical vapor deposition. The compositional, structural, and magnetic properties of the hetero-structure have been characterized and discussed. From the characterizations, the hetero-structure has been successfully grown generally. However, due to the unintentional diffusion of Ga ions from Ga{sub 2}O{sub 3}/GaN layers, the most part of the nominal Fe{sub 3}O{sub 4} layer is actually in the form of Ga{sub x}Fe{sub 3−x}O{sub 4} with gradually decreased x values from the Fe{sub 3}O{sub 4}/Ga{sub 2}O{sub 3} interface to the Fe{sub 3}O{sub 4} surface. Post-annealing process can further aggravate the diffusion. Due to the similar ionic radius of Ga and Fe, the structural configuration of the Ga{sub x}Fe{sub 3−x}O{sub 4} does not differ from that of pure Fe{sub 3}O{sub 4}. However, the ferromagnetism has been reduced with the incorporation of Ga into Fe{sub 3}O{sub 4}, which has been explained by the increased Yafet-Kittel angles in presence of considerable amount of Ga incorporation. A different behavior of the magnetoresistance has been found on the as-grown and annealed samples, which could be modelled and explained by the competition between the spin-dependent and spin-independent conduction channels. This work has provided detailed information on the interfacial properties of the Fe{sub 3}O{sub 4}/Ga{sub 2}O{sub 3}/GaN spin injecting hetero-structure, which is the solid basis for further improvement and application of

Low temperature transient response and electroluminescence characteristics of OLEDs based on Alq{sub 3}

Energy Technology Data Exchange (ETDEWEB)

Yuan, Chao [Key Laboratory of Semiconductor Material Sciences, Beijing Key Laboratory of Low Dimensional Semiconductor Materials and Devices, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083 (China); College of Materials Science and Optoelectronic Devices, University of Chinese Academy of Sciences, Beijing 100049 (China); Guan, Min, E-mail: guanmin@semi.ac.cn [Key Laboratory of Semiconductor Material Sciences, Beijing Key Laboratory of Low Dimensional Semiconductor Materials and Devices, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083 (China); Zhang, Yang [Key Laboratory of Semiconductor Material Sciences, Beijing Key Laboratory of Low Dimensional Semiconductor Materials and Devices, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083 (China); College of Materials Science and Optoelectronic Devices, University of Chinese Academy of Sciences, Beijing 100049 (China); Li, Yiyang; Liu, Shuangjie [Key Laboratory of Semiconductor Material Sciences, Beijing Key Laboratory of Low Dimensional Semiconductor Materials and Devices, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083 (China); Zeng, Yiping [Key Laboratory of Semiconductor Material Sciences, Beijing Key Laboratory of Low Dimensional Semiconductor Materials and Devices, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083 (China); College of Materials Science and Optoelectronic Devices, University of Chinese Academy of Sciences, Beijing 100049 (China)

2017-08-15

Highlights: • The dependency relation between transmission rate and electron transport layer is revealed. • The critical temperature points for the influence of luminescent materials and injection barriers on delay time are found. • The influence of light-emitting material and injection layer on carrier accumulation is quantified. - Abstract: In this work, the organic light-emitting diodes (OLEDs) based on Alq{sub 3} are fabricated. In order to make clear the transport mechanism of carriers in organic light-emitting devices at low temperature, detailed electroluminescence transient response and the current-voltage–luminescence (I–V–L) characteristics under different temperatures in those OLEDs are investigated. It founds that the acceleration of brightness increases with increasing temperature is maximum when the temperature is 200 K and it is mainly affected by the electron transport layer (Alq{sub 3}). The MoO{sub 3} injection layer and the electroluminescent layer have great influence on the delay time when the temperature is 200 K. Once the temperature is greater than 250 K, the delay time is mainly affected by the MoO{sub 3} injection layer. On the contrary, the fall time is mainly affected by the electroluminescent material. The V{sub f} is the average growth rate of fall time when the temperature increases 1 K which represents the accumulation rate of carriers. The difference between V{sub f} caused by the MoO{sub 3} injection layer is 0.52 us/K and caused by the electroluminescent material Ir(ppy){sub 3} is 0.73 us/K.

The 3D Printing of the Paralyzed Vocal Fold: Added Value in Injection Laryngoplasty.

Science.gov (United States)

Hamdan, Abdul-Latif; Haddad, Ghassan; Haydar, Ali; Hamade, Ramsey

2017-08-18

Three-dimensional (3D) printing has had numerous applications in various disciplines, especially otolaryngology. We report the first case of a high-fidelity 3D-printed model of the vocal cords of a patient with unilateral vocal cord paralysis in need of injection laryngoplasty. A case report was carried out. A tailored 3D-printed anatomically precise models for injection laryngoplasty has the potential to enhance preoperative planning, resident teaching, and patient education. A 3D printing model of the paralyzed vocal cord has an added value in the preoperative assessment of patients undergoing injection laryngoplasty. Copyright © 2017 The Voice Foundation. Published by Elsevier Inc. All rights reserved.

An experimental study of tracers for labelling of injection gas in oil reservoirs

International Nuclear Information System (INIS)

Dugstad, Oe.

1992-01-01

This work demonstrates the feasibility of the PMCP and PMCH as tracers in field experiments. These compounds have properties which make them as well suited for well to well studies as the more common tracers CH 3 T and 85 Kr. In an injection project carried out at the Gullfaks field in the North Sea the two PFCs verified communication between wells. This implies communication between different geological layers in the reservoir and also communication across faults within the same layers. Laboratory studies carried out have focused on the retention of the tracers in dynamic flooding experiments under conditions comparable with those in the petroleum reservoirs. Simultaneous injection of a variety of tracers has shown individual variations in tracer retention which are caused by important reservoir parameters as fluid saturation and rock properties. By proper design of field injection programs the tracers response may therefore be used to estimate fluid saturation if actual rock properties are known. 45 refs., 20 figs., 13 tabs

The research of new type stratified water injection process intelligent measurement technology

Science.gov (United States)

Zhao, Xin

2017-10-01

To meet the needs of injection and development of Daqing Oilfield, the injection of oil from the early stage of general water injection to the subdivision of water is the purpose of improving the utilization degree and the qualified rate of water injection, improving the performance of water injection column and the matching process. Sets of suitable for high water content of the effective water injection technology supporting technology. New layered water injection technology intelligent measurement technology will be more information testing and flow control combined into a unified whole, long-term automatic monitoring of the work of the various sections, in the custom The process has the characteristics of "multi-layer synchronous measurement, continuous monitoring of process parameters, centralized admission data", which can meet the requirement of subdivision water injection, but also realize the automatic synchronization measurement of each interval, greatly improve the efficiency of tiered injection wells to provide a new means for the remaining oil potential.

Water injection dredging

NARCIS (Netherlands)

Verhagen, H.J.

2000-01-01

Some twenty years ago WIS-dredging has been developed in the Netherlands. By injecting water into the mud layer, the water content of the mud becomes higher, it becomes fluid mud and will start to flow. The advantages of this system are that there is no need of transporting the mud in a hopper, and

Percutaneous intradiscal ozone (O3)-injection: an experimental study in canines

International Nuclear Information System (INIS)

Yu Zhijian; He Xiaofeng; Chen Yong; Zeng Qingle; Liu Chihong; Zhao Zhongqing; Lu Yong; Li Yanhao

2002-01-01

Objective: To evaluate the influence of ozone on normal nucleus pulpous and the safety of intradiscal ozone-injection for the treatment of herniated lumbar disc. Methods: Ozone was injected into selected lumbar discs (3 ml) and the para-spinal space (7 ml) with 20 G Chiba needle under fluoroscopy in five canines. The ozone concentration was 30 μg/ml and 50 μg/ml respectively. Two discs were selected for each concentration. Total 20 discs were injected. Three of the canines were given one-time ozone-injection and were sacrificed for pathology one week, one month and two months respectively after the procedure, and the other two canines were given two-time ozone-injection and were sacrificed one month and two months respectively after the procedure. The specimens including nucleus pulpous, end-plate, spinal cord, nerve root, and greater psoas muscle were observed macroscopically and microscopically. Results: No serious behavior abnormalities were observed in all animals. The atrophy of nucleus pulpous could be observed one month after ozone-injection due to significant reduction of water and extensive proliferation of collagenous fiber. The influence on the atrophy of nucleus pulpous demonstrated no apparent difference between the selected two concentrations of ozone, but was more apparent with two-time injection than that with one-time injection. The end-plates increased slightly or moderately in thickness in 16 simples and a few of fibers in greater psoas muscle suffered slight atrophy in 5 samples. Conclusion: It is suggested that percutaneous intradiscal ozone-injection is a safe method, and can cause gradual atrophy of nucleus pulpous. This study provides the evidence of the feasibility and value of this procedure's application in clinics

Supramolecular Layer-by-Layer Assembly of 3D Multicomponent Nanostructures via Multivalent Molecular Recognition

NARCIS (Netherlands)

Ling, X.Y.; Phang, In Yee; Reinhoudt, David; Vancso, Gyula J.; Huskens, Jurriaan

2008-01-01

The supramolecular layer-by-layer assembly of 3D multicomponent nanostructures of nanoparticles is demonstrated. Nanoimprint lithography (NIL) was used as the patterning tool for making patterned β-cyclodextrin (CD) self-assembled monolayers (SAMs) and for the confinement of nanoparticles on the

The importance of dye chemistry and TiCl4 surface treatment in the behavior of Al2O3 recombination barrier layers deposited by atomic layer deposition in solid-state dye-sensitized solar cells

KAUST Repository

Brennan, Thomas P.

2012-01-01

Atomic layer deposition (ALD) was used to fabricate Al 2O 3 recombination barriers in solid-state dye-sensitized solar cells (ss-DSSCs) employing an organic hole transport material (HTM) for the first time. Al 2O 3 recombination barriers of varying thickness were incorporated into efficient ss-DSSCs utilizing the Z907 dye adsorbed onto a 2 μm-thick nanoporous TiO 2 active layer and the HTM spiro-OMeTAD. The impact of Al 2O 3 barriers was also studied in devices employing different dyes, with increased active layer thicknesses, and with substrates that did not undergo the TiCl 4 surface treatment. In all instances, electron lifetimes (as determined by transient photovoltage measurements) increased and dark current was suppressed after Al 2O 3 deposition. However, only when the TiCl 4 treatment was eliminated did device efficiency increase; in all other instances efficiency decreased due to a drop in short-circuit current. These results are attributed in the former case to the similar effects of Al 2O 3 ALD and the TiCl 4 surface treatment whereas the insulating properties of Al 2O 3 hinder charge injection and lead to current loss in TiCl 4-treated devices. The impact of Al 2O 3 barrier layers was unaffected by doubling the active layer thickness or using an alternative ruthenium dye, but a metal-free donor-π-acceptor dye exhibited a much smaller decrease in current due to its higher excited state energy. We develop a model employing prior research on Al 2O 3 growth and dye kinetics that successfully predicts the reduction in device current as a function of ALD cycles and is extendable to different dye-barrier systems. © This journal is the Owner Societies 2012.

The growth of mid-infrared emitting InAsSb/InAsP strained-layer superlattices using metal-organic chemical vapor deposition

International Nuclear Information System (INIS)

Biefeld, R.M.; Allerman, A.A.; Kurtz, S.R.; Burkhart, J.H.

1997-01-01

We describe the metal-organic chemical vapor deposition os InAsSb/InAsP strained-layer superlattice (SLS) active regions for use in mid-infrared emitters. These SLSs were grown at 500 degrees C, and 200 torr in a horizontal quartz reactor using trimethylindium, triethylantimony, AsH 3 , and PH 3 . By changing the layer thickness and composition we have prepared structures with low temperature (≤20K) photoluminescence wavelengths ranging from 3.2 to 5.0 μm. Excellent performance was observed for an SLS light emitting diode (LED) and both optically pumped and electrically injected SLS layers. An InAsSb/InAsP SLS injection laser emitted at 3.3 μm at 80 K with peak power of 100 mW

Variation of the refractive index for the active layer of the double heterostructure GaAlAsSb/GaInAsSb/GaAlAsSb in injected mode

International Nuclear Information System (INIS)

Mohou, M.A.

1995-01-01

This work reports on the influence of the injected current on the refractive index in the active layer of GaInAsSb/GaAlAsSb laser diodes. These diodes present at threshold a full beam width at half power θ perpendicular of about 52 deg. C. The fluctuation of the refractive index caused by the injection of free carriers was studied on the basis of the evolution of θ perpendicular as a function of the injected current. It was shown that the inversion of the population which follows the rising of the gain, causes a slight decrease of the refractive index. 12 refs, 5 figs

Three-dimensional simulation of H-mode plasmas with localized divertor impurity injection on Alcator C-Mod using the edge transport code EMC3-EIRENE

International Nuclear Information System (INIS)

Lore, J. D.; Reinke, M. L.; Lipschultz, B.; Brunner, D.; LaBombard, B.; Terry, J.; Pitts, R. A.; Feng, Y.

2015-01-01

Experiments in Alcator C-Mod to assess the level of toroidal asymmetry in divertor conditions resulting from poloidally and toroidally localized extrinsic impurity gas seeding show a weak toroidal peaking (∼1.1) in divertor electron temperatures for high-power enhanced D-alpha H-mode plasmas. This is in contrast to similar experiments in Ohmically heated L-mode plasmas, which showed a clear toroidal modulation in the divertor electron temperature. Modeling of these experiments using the 3D edge transport code EMC3-EIRENE [Y. Feng et al., J. Nucl. Mater. 241, 930 (1997)] qualitatively reproduces these trends, and indicates that the different response in the simulations is due to the ionization location of the injected nitrogen. Low electron temperatures in the private flux region (PFR) in L-mode result in a PFR plasma that is nearly transparent to neutral nitrogen, while in H-mode the impurities are ionized in close proximity to the injection location, with this latter case yielding a largely axisymmetric radiation pattern in the scrape-off-layer. The consequences for the ITER gas injection system are discussed. Quantitative agreement with the experiment is lacking in some areas, suggesting potential areas for improving the physics model in EMC3-EIRENE

Creating fluid injectivity in tar sands formations

Science.gov (United States)

Stegemeier, George Leo; Beer, Gary Lee; Zhang, Etuan

2010-06-08

Methods for treating a tar sands formation are described herein. Methods for treating a tar sands may include heating a portion of a hydrocarbon layer in the formation from one or more heaters located in the portion. The heat may be controlled to increase the permeability of at least part of the portion to create an injection zone in the portion with an average permeability sufficient to allow injection of a fluid through the injection zone. A drive fluid and/or an oxidizing fluid may be provided into the injection zone. At least some hydrocarbons are produced from the portion.

Validity and Realibity of the Turkish form of the Emotion Regulation Questionnaire

Directory of Open Access Journals (Sweden)

Tarik TOTAN

2015-12-01

Conclusion: The research showed that ERQ has got psychometric quality in Turkish for using as reappraisal and suppression factors. Consequently, the scale can be used in person or group focused psychotherapy and research. [JCBPR 2015; 4(3.000: 153-161

Verification of zinc injection applicability to Japanese BWRs

International Nuclear Information System (INIS)

Hosokawa, H.; Uetake, N.; Ishida, K.; Nakamura, M.; Mochizuki, K.; Nagata, T.; Ogawa, N.; Baba, T.; Ono, S.; Ishigure, K.

2002-01-01

The verification test program on zinc injection applicability to Japanese BWRs was started in 1997. Laboratory tests using high temperature water loops under BWR reactor water conditions are in progress. This paper is an interim report on results obtained so far. Co-58 and Zn-65 were simultaneously used in the Co radioactivity buildup test to evaluate zinc injection suppression effects towards cobalt deposition on pre-oxidized stainless steel. The following results were obtained. The Co deposition was suppressed effectively by Zn injection, even when there was a pre-oxide film. For the test piping that had the pre-oxide film formed under the NWC (normal water chemistry) condition, when soaked under the HWC (hydrogen water chemistry) condition a large amount of Co-58 was taken into a small part of the inner layer. The distribution ratio of Co-58 in the inner layer and outer layer of the oxide film was almost the same for both the pre-oxidized test piping and the non pre-oxidized test piping under the HWC condition. Zn injection decreased the Co concentration in the inner layer of the oxide film under all conditions. The effect of gamma ray irradiation on the incorporation of Co into the oxide film is small. Gamma ray irradiation influenced the Co incorporation behavior complexly. The change of the Co amount incorporated into the non-pre-filmed specimen were small relatively, but the incorporation into the pre-filmed specimen promotes distinctly. Zn addition effectively suppresses the Co incorporation even gamma ray irradiation. (authors)

Spin injection into semiconductors: the role of Fe/AlxGa1-xAs interface

International Nuclear Information System (INIS)

Fitzsimmons, M.R.; Park, S.

2004-01-01

The influence of the growth and post-growth annealing temperatures of Fe/Al x Ga 1-x As-based spin light-emitting diodes (LEDs) on the spin injection efficiency is discussed. The extent of interfacial reactions during molecular beam epitaxial growth of Fe on GaAs was determined from in-situ x-ray photoelectron spectroscopy studies. The Fe/GaAs interface results in ≤ 3 monolayers of reaction for Fe grown at -15 C. Intermediate growth temperatures (95 C) lead to ∼5 monolayers of interfacial reactions, and high growth temperatures of 175 C lead to a ∼9 monolayer thick reacted layer. Polarized neutron reflectivity was used to determine the interfacial magnetic properties of epitaxial Fe 0.5 Co 0.5 /GaAs heterostructures grown under identical conditions. No interfacial magnetic dead layer is detected at the interface for Fe 0.5 Co 0.5 films grown at -15 C, an ∼6 (angstrom) thick nonmagnetic layer formed at the interface for 95 C growth and an ∼5 (angstrom) thick magnetic interfacial reacted layer formed for growth at 175 C. Spin injection from Fe contacts into spin LEDs decreases sharply when reactions result in a nonmagnetic interfacial layer. Significant spin injection signals are obtained from Fe contacts grown between -5 C and 175 C, although the higher Fe growth temperatures resulted in a change in the sign of the spin polarization. Post-growth annealing of the spin LEDs is found to increase spin injection efficiency for low Fe growth temperatures and to a sign reversal of the spin polarization for high growth temperature (175 C). An effective Schottky barrier height increase indicates that post growth annealing modifies the Fe/Al x Ga 1-x As interface.

Photo-Crosslinking of Pendent Uracil Units Provides Supramolecular Hole Injection/Transport Conducting Polymers for Highly Efficient Light-Emitting Diodes

Directory of Open Access Journals (Sweden)

Hsi-Kang Shih

2015-04-01

Full Text Available A new process for modifying a polymeric material for use as a hole injection transport layer in organic light-emitting diodes has been studied, which is through 2π + 2π photodimerization of a DNA-mimetic π-conjugated poly(triphenylamine-carbazole presenting pendent uracil groups (PTC-U under 1 h of UV irradiation. Multilayer florescence OLED (Organic light-emitting diodes device with the PTC-U-1hr as a hole injection/transport layer (ITO (Indium tin oxide/HITL (hole-injection/transport layer (15 nm/N,N'-di(1-naphthyl- N,N'-diphenyl-(1,1'-biphenyl-4,4'-diamine (NPB (15 nm/Tris-(8-hydroxyquinoline aluminum (Alq3 (60 nm/LiF (1 nm/Al (100 nm is fabricated, a remarkable improvement in performance (Qmax (external quantum efficiency = 2.65%, Bmax (maximum brightness = 56,704 cd/m2, and LE (luminance efficiencymax = 8.9 cd/A relative to the control PTC-U (Qmax = 2.40%, Bmax = 40,490 cd/m2, and LEmax = 8.0 cd/A. Multilayer phosphorescence OLED device with the PTC-U-1hr as a hole injection/transport layer (ITO/HITL (15 nm/Ir(ppy3:PVK (40 nm/BCP (10nm/Alq3 (40 nm/LiF (1 nm/Al (100 nm is fabricated by successive spin-coating processes, a remarkable improvement in performance (Qmax = 9.68%, Bmax = 41,466 cd/m2, and LEmax = 36.6 cd/A relative to the control PTC-U (Qmax = 8.35%, Bmax = 34,978 cd/m2, and LEmax = 30.8 cd/A and the commercial product (poly(3,4-ethylenedioxythiophene:polystyrenesulfonate PEDOT:PSS (Qmax = 4.29%, Bmax = 15,678 cd/m2, and LEmax = 16.2 cd/A has been achieved.

Subcutaneous injection of thallium-201 chloride and gallium-67 citrate at acupuncture point K-3

International Nuclear Information System (INIS)

Johg, Shiang-Bin; Wu, Chung-Chieng; Chen, Ming-Feng; Wu, Sheng-Nan

1992-01-01

Subcutaneous (SC) injection of 99m Tc pertechnetate ( 99m Tc) at acupuncture points K-3 is a new method of lower-limb radionuclide venography. To investigate the mechanism of absorption of 99m Tc from SC injected sites into vascular system, various radioisotopes such as 201 Tl chloride ( 201 Tl) and 67 Ga citrate ( 67 Ga) were SC injected at K-3 points in animal and human-beings experiments. It was found that 99m Tc and 201 Tl were absorbed rapidly from K-3 points through venous system and into whole body soft tissue. However, 67 Ga with a larger effective ionic radius than 201 Tl was not absorbed throughout the observation of 5 minutes. Furthermore, intravenous administration of digitalis, a Na + -K + pump blocker, did not inhibit the absorption of 99m Tc and 201 Tl after SC injection at K-3 points. These results suggest that absorption of radionuclides on SC injection at K-3 points is mainly through the passive pathway of diffusion rather than the active transport, and the effective ionic radius may be a major factor influencing the absorption rate of the radionuclides. (author)

On the Hole Injection for III-Nitride Based Deep Ultraviolet Light-Emitting Diodes.

Science.gov (United States)

Li, Luping; Zhang, Yonghui; Xu, Shu; Bi, Wengang; Zhang, Zi-Hui; Kuo, Hao-Chung

2017-10-24

The hole injection is one of the bottlenecks that strongly hinder the quantum efficiency and the optical power for deep ultraviolet light-emitting diodes (DUV LEDs) with the emission wavelength smaller than 360 nm. The hole injection efficiency for DUV LEDs is co-affected by the p-type ohmic contact, the p-type hole injection layer, the p-type electron blocking layer and the multiple quantum wells. In this report, we review a large diversity of advances that are currently adopted to increase the hole injection efficiency for DUV LEDs. Moreover, by disclosing the underlying device physics, the design strategies that we can follow have also been suggested to improve the hole injection for DUV LEDs.

The Effect of Single Pyramidal Neuron Firing Within Layer 2/3 and Layer 4 in Mouse V1.

Science.gov (United States)

Meyer, Jochen F; Golshani, Peyman; Smirnakis, Stelios M

2018-01-01

The influence of cortical cell spiking activity on nearby cells has been studied extensively in vitro . Less is known, however, about the impact of single cell firing on local cortical networks in vivo . In a pioneering study, Kwan and Dan (Kwan and Dan, 2012) reported that in mouse layer 2/3 (L2/3), under anesthesia , stimulating a single pyramidal cell recruits ~2.1% of neighboring units. Here we employ two-photon calcium imaging in layer 2/3 of mouse V1, in conjunction with single-cell patch clamp stimulation in layer 2/3 or layer 4, to probe, in both the awake and lightly anesthetized states , how (i) activating single L2/3 pyramidal neurons recruits neighboring units within L2/3 and from layer 4 (L4) to L2/3, and whether (ii) activating single pyramidal neurons changes population activity in local circuit. To do this, it was essential to develop an algorithm capable of quantifying how sensitive the calcium signal is at detecting effectively recruited units ("followers"). This algorithm allowed us to estimate the chance of detecting a follower as a function of the probability that an epoch of stimulation elicits one extra action potential (AP) in the follower cell. Using this approach, we found only a small fraction (layer-2/3 or layer-4 pyramidal neurons produces few (<1% of local units) reliable single-cell followers in L2/3 of mouse area V1, either under light anesthesia or in quiet wakefulness: instead, single cell stimulation was found to elevate aggregate population activity in a weak but highly distributed fashion.

The development of new injection septum magnet for upgrating of J-PARC MR (3)

International Nuclear Information System (INIS)

Shibata, Tatsunobu; Ishii, Koji; Sugimoto, Takuya; Matsumoto, Noriyuki; Matsumoto, Hiroshi; Fan, Kuanjun; Kawaguchi, Yusuke; Nakamura, Kenta; Hamano, Kei

2017-01-01

We are improving the Main Ring (MR) for beam power of 750 kW which is a first goal of J-PARC. The repetition period of the Fast eXtraction(FX) must be shorten to 1.3 sec from the current period of 2.48 sec for the improvement of the beam power. We must upgrade injection and extraction magnets and their power supplies for upgrading the beam power. In 2016 summer, we have finished the replacement of a high field injection septum magnet and its power supply. One of the main reason was that the previous injection septum system could not be operated with 1.3 sec repetition. The other thing was that we have confirmed the large leakage field around circulating beam line of the injection magnet, so we must reduce them. The new injection septum magnet and its power supply were produced in 2014. We started to conduct the test-operation of the power supply and measurement of the magnetic field in 2015, and finished in August 2016, We have started the beam operation with the new injection septum in October 2016. The converter units in the new power supply of the new injection septum were broken in October and November 2016 as initial trouble. The main source of the trouble was electric noise in the gate signal. After countermeasure, we have no trouble in the power supply. We have found that there is still small leakage field in the upstream line of the new injection septum. We have installed an additional magnetic shield to the new injection septum. (author)

Medical simulator with injection device

NARCIS (Netherlands)

2011-01-01

medical simulator 611 comprises a vessel 609 representing a simulated blood vessel. The vessel comprises a simulated vessel wall capable of being punctured by an electrically conductive injection needle 503. The vessel wall comprises a first electrically conductive layer for closing an electric

Removal rate of ( sup 3 H)hyaluronan injected subcutaneously in rabbits

Energy Technology Data Exchange (ETDEWEB)

Reed, R.K.; Laurent, U.B.; Fraser, J.R.; Laurent, T.C. (Univ. of Bergen (Norway))

1990-08-01

Hyaluronan is an important constituent of the extracellular matrix in skin, and recent studies suggest that there is a pool of easily removable (free) hyaluronan drained by lymph. The removal rate of free hyaluronan in skin was measured from the elimination of ({sup 3}H)hyaluronan, injected subcutaneously in 13 rabbits. The removal of radioactivity was determined from appearance of {sup 3}H in plasma. During the first 24 h after injection, 10-87% of the tracer entered blood, less in injectates with high concentrations of hyaluronan. The removal was monoexponential with a half-life of 0.5-1 day when concentration of hyaluronan was 5 mg/ml or less. When hyaluronan concentration was 10 mg/ml or higher, the removal was slow for about 24 h and then became similar to that in experiments with low hyaluronan concentration. Free hyaluronan at physiological concentrations is thus turned over with the same rate as serum albumin, supporting the concept that hyaluronan is removed essentially by lymph flow to be degraded in lymph nodes and liver.

Trap effect of an ultrathin DCJTB layer in organic light-emitting diodes

Energy Technology Data Exchange (ETDEWEB)

Wang Yuanmin [Institute of Optoelectronic Technology, Key Laboratory for Information Storage, Displays and Materials, Beijing Jiaotong University, Beijing 100044 (China); Teng Feng [Institute of Optoelectronic Technology, Key Laboratory for Information Storage, Displays and Materials, Beijing Jiaotong University, Beijing 100044 (China)]. E-mail: advanced9898@126.com; Xu Zheng [Institute of Optoelectronic Technology, Key Laboratory for Information Storage, Displays and Materials, Beijing Jiaotong University, Beijing 100044 (China); Hou Yanbing [Institute of Optoelectronic Technology, Key Laboratory for Information Storage, Displays and Materials, Beijing Jiaotong University, Beijing 100044 (China); Yang Shengyi [Institute of Optoelectronic Technology, Key Laboratory for Information Storage, Displays and Materials, Beijing Jiaotong University, Beijing 100044 (China); Xu Xurong [Institute of Optoelectronic Technology, Key Laboratory for Information Storage, Displays and Materials, Beijing Jiaotong University, Beijing 100044 (China)

2005-08-15

An improved performance of organic light-emitting diodes has been obtained by using 4-(dicyanomethylene)-2-t-butyl-6-(1,1,7,7-tetramethyljulolidyl-9-enyl) -4Hpyran (DCJTB) as an ultrathin emitting layer. When 0.1 nm DCJTB was inserted between the hole-transporting layer and electron-transporting layer, for an unoptimized device indium-tin oxide (ITO)/naphtylphenyliphenyl diamine (NPB)/DCJTB (0.1 nm)/8-hydroxyquinoline aluminum (Alq{sub 3})/Al, the maximum brightness was 1531 cd m{sup -2} at 15 V. Compared with doped devices ITO/NPB/Alq{sub 3}:DCJTB (1%)/Alq{sub 3}/LiF/Al, a higher efficiency has been achieved. Compared with the conventional device ITO/NPB/Alq{sub 3}/Al, the inserted device has a slightly higher current efficiency and lower turn-on voltage. We suggest the ultrathin DCJTB layer acts as trap for carriers, and the accumulated holes at the hole-transport layer/electron-transport layer interface have enhanced the electric field in the electron-transport layer and improved the electron injection at the cathode.

Low temperature transient response and electroluminescence characteristics of OLEDs based on Alq3

Science.gov (United States)

Yuan, Chao; Guan, Min; Zhang, Yang; Li, Yiyang; Liu, Shuangjie; Zeng, Yiping

2017-08-01

In this work, the organic light-emitting diodes (OLEDs) based on Alq3 are fabricated. In order to make clear the transport mechanism of carriers in organic light-emitting devices at low temperature, detailed electroluminescence transient response and the current-voltage-luminescence (I-V-L) characteristics under different temperatures in those OLEDs are investigated. It founds that the acceleration of brightness increases with increasing temperature is maximum when the temperature is 200 K and it is mainly affected by the electron transport layer (Alq3). The MoO3 injection layer and the electroluminescent layer have great influence on the delay time when the temperature is 200 K. Once the temperature is greater than 250 K, the delay time is mainly affected by the MoO3 injection layer. On the contrary, the fall time is mainly affected by the electroluminescent material. The Vf is the average growth rate of fall time when the temperature increases 1 K which represents the accumulation rate of carriers. The difference between Vf caused by the MoO3 injection layer is 0.52 us/K and caused by the electroluminescent material Ir(ppy)3 is 0.73 us/K.

Control of Alq3 wetting layer thickness via substrate surface functionalization.

Science.gov (United States)

Tsoi, Shufen; Szeto, Bryan; Fleischauer, Michael D; Veinot, Jonathan G C; Brett, Michael J

2007-06-05

The effects of substrate surface energy and vapor deposition rate on the initial growth of porous columnar tris(8-hydroxyquinoline)aluminum (Alq3) nanostructures were investigated. Alq3 nanostructures thermally evaporated onto as-supplied Si substrates bearing an oxide were observed to form a solid wetting layer, likely caused by an interfacial energy mismatch between the substrate and Alq3. Wetting layer thickness control is important for potential optoelectronic applications. A dramatic decrease in wetting layer thickness was achieved by depositing Alq3 onto alkyltrichlorosilane-derivatized Si/oxide substrates. Similar effects were noted with increasing deposition rates. These two effects enable tailoring of the wetting layer thickness.

EMC3-EIRENE modeling of toroidally-localized divertor gas injection experiments on Alcator C-Mod

Energy Technology Data Exchange (ETDEWEB)

Lore, J.D., E-mail: lorejd@ornl.gov [Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); Reinke, M.L. [York Plasma Institute, Department of Physics, University of York, Heslington, York YO10 5DD (United Kingdom); LaBombard, B. [Plasma Science and Fusion Center, MIT, Cambridge, MA 02139 (United States); Lipschultz, B. [York Plasma Institute, Department of Physics, University of York, Heslington, York YO10 5DD (United Kingdom); Churchill, R.M. [Plasma Science and Fusion Center, MIT, Cambridge, MA 02139 (United States); Pitts, R.A. [ITER Organization, Route de Vinon sur Verdon, 13115 Saint Paul Lez Durance (France); Feng, Y. [Max Planck Institute for Plasma Physics, Greifswald (Germany)

2015-08-15

Experiments on Alcator C-Mod with toroidally and poloidally localized divertor nitrogen injection have been modeled using the three-dimensional edge transport code EMC3-EIRENE to elucidate the mechanisms driving measured toroidal asymmetries. In these experiments five toroidally distributed gas injectors in the private flux region were sequentially activated in separate discharges resulting in clear evidence of toroidal asymmetries in radiated power and nitrogen line emission as well as a ∼50% toroidal modulation in electron pressure at the divertor target. The pressure modulation is qualitatively reproduced by the modeling, with the simulation yielding a toroidal asymmetry in the heat flow to the outer strike point. Toroidal variation in impurity line emission is qualitatively matched in the scrape-off layer above the strike point, however kinetic corrections and cross-field drifts are likely required to quantitatively reproduce impurity behavior in the private flux region and electron temperatures and densities directly in front of the target.

Impact of CH3NH3PbI3-PCBM bulk heterojunction active layer on the photovoltaic performance of perovskite solar cells

Science.gov (United States)

Chaudhary, Dhirendra K.; Kumar, Pankaj; Kumar, Lokendra

2017-10-01

We report here the impact of CH3NH3PbI3-PCBM bulk heterojunction (BHJ) active layer on the photovoltaic performance of perovskite solar cells. The solar cells were prepared in normal architecture on FTO coated glass substrates with compact TiO2 (c-TiO2) layer on FTO as electron transport layer (ETL) and poly(3-hexylthiophene) (P3HT) as hole transport layer (HTL). For comparison, a few solar cells were also prepared in planar heterojunction structure using CH3NH3PbI3 only as the active layer. The bulk heterojunction CH3NH3PbI3-PCBM active layer exhibited very large crystalline grains of 2-3 μm compared to ∼150 nm only in CH3NH3PbI3 active layer. Larger grains in bulk-heterojunction solar cells resulted in enhanced power conversion efficiency (PCE) through enhancement in all the photovoltaic parameters compared to planar heterojunction solar cells. The bulk-heterojunction solar cells exhibited ∼9.25% PCE with short circuit current density (Jsc) of ∼18.649 mA/cm2, open circuit voltage (Voc) of 0.894 V and Fill Factor (FF) of 0.554. There was ∼36.9% enhancement in the PCE of bulk-heterojunction solar cells compared to that of planar heterojunction solar cells. The larger grains are formed as a result of incorporation on PCBM in the active layer.

Effect of heterostructure design on carrier injection and emission characteristics of 295 nm light emitting diodes

Energy Technology Data Exchange (ETDEWEB)

Mehnke, Frank, E-mail: mehnke@physik.tu-berlin.de; Kuhn, Christian; Stellmach, Joachim; Rothe, Mark-Antonius; Reich, Christoph; Ledentsov, Nikolay; Pristovsek, Markus; Wernicke, Tim [Technische Universität Berlin, Institut für Festkörperphysik, Hardenbergstr. 36, EW 6-1, 10623 Berlin (Germany); Kolbe, Tim; Lobo-Ploch, Neysha; Rass, Jens [Ferdinand-Braun-Institut, Leibniz-Institut für Höchstfrequenztechnik, Gustav-Kirchhoff-Str. 4, 12489 Berlin (Germany); Kneissl, Michael [Technische Universität Berlin, Institut für Festkörperphysik, Hardenbergstr. 36, EW 6-1, 10623 Berlin (Germany); Ferdinand-Braun-Institut, Leibniz-Institut für Höchstfrequenztechnik, Gustav-Kirchhoff-Str. 4, 12489 Berlin (Germany)

2015-05-21

The effects of the heterostructure design on the injection efficiency and external quantum efficiency of ultraviolet (UV)-B light emitting diodes (LEDs) have been investigated. It was found that the functionality of the Al{sub x}Ga{sub 1−x}N:Mg electron blocking layer is strongly influenced by its aluminum mole fraction x and its magnesium doping profile. By comparing LED electroluminescence, quantum well photoluminescence, and simulations of LED heterostructure, we were able to differentiate the contributions of injection efficiency and internal quantum efficiency to the external quantum efficiency of UV LEDs. For the optimized heterostructure using an Al{sub 0.7}Ga{sub 0.3}N:Mg electron blocking layer with a Mg to group III ratio of 4% in the gas phase the electron leakage currents are suppressed without blocking the injection of holes into the multiple quantum well active region. Flip chip mounted LED chips have been processed achieving a maximum output power of 3.5 mW at 290 mA and a peak external quantum efficiency of 0.54% at 30 mA.

Effect of heterostructure design on carrier injection and emission characteristics of 295 nm light emitting diodes

International Nuclear Information System (INIS)

Mehnke, Frank; Kuhn, Christian; Stellmach, Joachim; Rothe, Mark-Antonius; Reich, Christoph; Ledentsov, Nikolay; Pristovsek, Markus; Wernicke, Tim; Kolbe, Tim; Lobo-Ploch, Neysha; Rass, Jens; Kneissl, Michael

2015-01-01

The effects of the heterostructure design on the injection efficiency and external quantum efficiency of ultraviolet (UV)-B light emitting diodes (LEDs) have been investigated. It was found that the functionality of the Al x Ga 1−x N:Mg electron blocking layer is strongly influenced by its aluminum mole fraction x and its magnesium doping profile. By comparing LED electroluminescence, quantum well photoluminescence, and simulations of LED heterostructure, we were able to differentiate the contributions of injection efficiency and internal quantum efficiency to the external quantum efficiency of UV LEDs. For the optimized heterostructure using an Al 0.7 Ga 0.3 N:Mg electron blocking layer with a Mg to group III ratio of 4% in the gas phase the electron leakage currents are suppressed without blocking the injection of holes into the multiple quantum well active region. Flip chip mounted LED chips have been processed achieving a maximum output power of 3.5 mW at 290 mA and a peak external quantum efficiency of 0.54% at 30 mA

Photoluminescence and photostability of YVO{sub 4}:Eu{sup 3+} nanoparticle/layered double hydroxide multilayer films prepared via layer-by-layer assembly

Energy Technology Data Exchange (ETDEWEB)

Onishi, Wataru; Takeshita, Satoru, E-mail: takeshita@applc.keio.ac.jp; Iso, Yoshiki; Isobe, Tetsuhiko, E-mail: isobe@applc.keio.ac.jp

2016-07-15

Layered double hydroxides (LDHs) consist of positively charged brucite-like layers with interlayer anions for charge compensation. Delaminated cationic LDH nanosheets can be used as building blocks to fabricate functional nanocomposites. In this study, we fabricated photoluminescent multilayer films containing positively charged LDH nanosheets and negatively charged YVO{sub 4}:Eu{sup 3+} nanoparticles on quartz glass substrates through a layer-by-layer assembly technique. The absorbance and photoluminescence (PL) intensity of the YVO{sub 4}:Eu{sup 3+} nanoparticles in the multilayer films were proportional to the number of deposition cycles. These linear relationships indicate that constant amounts of LDH nanosheets and YVO{sub 4}:Eu{sup 3+} nanoparticles were alternately deposited on the substrate. The change in intensity of the 620 nm emission of the YVO{sub 4}:Eu{sup 3+} nanoparticle powder and the multilayer film (LDH/YVO{sub 4}:Eu{sup 3+}){sub 10} under continuous 270 nm excitation was measured to compare both photostabilities. The PL intensity of the YVO{sub 4}:Eu{sup 3+} nanoparticle powder decreased to 7% of the initial intensity and then gradually recovered to 19%. In contrast, the PL intensity of the multilayer film (LDH/YVO{sub 4}:Eu{sup 3+}){sub 10} decreased to 36% of the initial intensity and then recovered to 139%. The photo-degradation and recovery are discussed.

Deep-well injection of liquid radioactive waste in Russia. Present situation

International Nuclear Information System (INIS)

Rybalchenko, A.

1998-01-01

At present there are 3 facilities (polygons) for the deep-well injection of liquid radioactive waste in Russia, all of which were constructed in the mid60's. These facilities are operating successfully, and activities have started in preparation for decommissioning. Liquid radioactive waste is injected into deep porous horizons which act as 'collector-layers', isolated from the surface and from groundwaters by a relatively thick sequence of rock of low permeability. The collector-layers (also collector-horizons) contain salt waters or fresh waters of no practical application, lying beneath the main horizons containing potable waters. Construction of facilities for the deep-well injection of liquid radioactive waste was preceded by geological surveys and investigations which were able to substantiate the feasibility and safety of radioactive waste injection, and to obtain initial data for facility design. Operation of the facilities was accompanied by monitoring which confirmed that the main safety requirement was satisfied i.e. localisation of radioactive waste within specified boundaries of the geologic medium. The opinion of most specialists in the atomic power industry in Russia favours deep-well injection as a solution to the problem of liquid radioactive waste management; during the period of active operation of defence facilities (atomic power industry of the former U.S.S.R.), this disposal method prevented the impact of radioactive waste on man and the environment. The experience accumulated concerning the injection of liquid radioactive waste in Russia is of interest to scientists and engineers engaged in problems of protection and remediation of the environment in the vicinity of nuclear industry facilities; an example of the utilisation of the deep subsurface for solidified radioactive waste and the disposal of different types of nuclear materials. Information on the scientific principles and background for the development of facilities for the injection

Direct Observation of Ultrafast Hole Injection from Lead Halide Perovskite by Differential Transient Transmission Spectroscopy.

Science.gov (United States)

Ishioka, Kunie; Barker, Bobby G; Yanagida, Masatoshi; Shirai, Yasuhiro; Miyano, Kenjiro

2017-08-17

Efficient charge separation at the interfaces of the perovskite with the carrier transport layers is crucial for perovskite solar cells to achieve high power conversion efficiency. We present a systematic experimental study on the hole injection dynamics from MAPbI 3 perovskite to three typical hole transport materials (HTMs). We extract the carrier dynamics directly related to the hole injection by employing a pump light with short absorption depth and comparing the transient transmission signals excited on the two sides of the sample. The differential transmission signals reveal the hole injections to PTAA and PEDOT:PSS to be complete within 1 and 2 ps, respectively, and that to NiO x to exhibit an additional slow process on a 40 ps time scale. The obtained injection dynamics are discussed in comparison with the device performance of the solar cells containing the same MAPbI 3 /HTM interfaces.

YCu(TeO32(NO3(H2O3: a novel layered tellurite

Directory of Open Access Journals (Sweden)

Stuart J. Mills

2016-08-01

Full Text Available A new hydrated yttrium copper tellurite nitrate, yttrium(III copper(II bis[trioxidotellurate(IV] nitrate trihydrate, has been synthesized hydrothermally in a Teflon-lined autoclave and structurally determined using synchrotron radiation. The new phase is the first example containing yttrium, copper and tellurium in one structure. Its crystal structure is unique, with relatively strongly bound layers extending parallel to (020, defined by YO8, CuO4 and TeO3 polyhedra, while the NO3− anions and one third of the water molecules lie between those layers. The structural unit consists of [Cu2(TeO34]4− loop-branched chains of {Cu...Te...Cu...Te} squares running parallel to [001], which are linked further into layers only through Y(O,H2O8 polyhedra. Weak `secondary' Te bonds and O—H...O hydrogen-bonding interactions, involving water molecules and layer O atoms, link the layers and interlayer species. IR spectroscopic data are also presented.

Gold work function reduction by 2.2 eV with an air-stable molecular donor layer

Energy Technology Data Exchange (ETDEWEB)

Broeker, Benjamin; Blum, Ralf-Peter; Frisch, Johannes; Rabe, Juergen P.; Koch, Norbert [Institut fuer Physik, Humboldt-Universitaet zu Berlin (Germany); Vollmer, Antje [Berliner Elektronenspeicherring-Gesellschaft fuer Synchrotronstrahlung mbH, Berlin (Germany); Hofmann, Oliver T.; Zojer, Egbert [Institut of Solid State Physics, Graz University of Technology (Austria); Rieger, Ralph; Muellen, Klaus [Max Planck Institut fuer Polymerforschung, Mainz (Germany)

2009-07-01

Ultraviolet photoelectron spectroscopy was used to investigate neutral methyl viologen (1,1'-dimethyl-1H,1'H-[4,4']bipyridinylidene, MV0) deposited on Au(111) surfaces. As a result of molecule-to-metal electron transfer, the work function of Au(111) was decreased from 5.5 eV to 3.3 eV. The energy levels of electron transport layers deposited on top of modified Au surfaces were shifted to higher binding energy compared to layers on pristine Au, and the electron injection barrier was reduced by 0.8 eV for tris(8-hydroxyquinoline)aluminum (Alq3) and by 0.7 eV for C60. The air-stable donor MV0 can thus be used to facilitate electron injection into organic semiconductors even from high work function metals.

Non-injection Drug Use and Injection Initiation Assistance among People Who Inject Drugs in Tijuana, Mexico.

Science.gov (United States)

Ben Hamida, Amen; Rafful, Claudia; Jain, Sonia; Sun, Shelly; Gonzalez-Zuniga, Patricia; Rangel, Gudelia; Strathdee, Steffanie A; Werb, Dan

2018-02-01

Although most people who inject drugs (PWID) report receiving assistance during injection initiation events, little research has focused on risk factors among PWID for providing injection initiation assistance. We therefore sought to determine the influence of non-injection drug use among PWID on their risk to initiate others. We used generalized estimating equation (GEE) models on longitudinal data among a prospective cohort of PWID in Tijuana, Mexico (Proyecto El Cuete IV), while controlling for potential confounders. At baseline, 534 participants provided data on injection initiation assistance. Overall, 14% reported ever initiating others, with 4% reporting this behavior recently (i.e., in the past 6 months). In a multivariable GEE model, recent non-injection drug use was independently associated with providing injection initiation assistance (adjusted odds ratio [AOR] = 2.42, 95% confidence interval [CI] = 1.39-4.20). Further, in subanalyses examining specific drug types, recent non-injection use of cocaine (AOR = 9.31, 95% CI = 3.98-21.78), heroin (AOR = 4.00, 95% CI = 1.88-8.54), and methamphetamine (AOR = 2.03, 95% CI = 1.16-3.55) were all significantly associated with reporting providing injection initiation assistance. Our findings may have important implications for the development of interventional approaches to reduce injection initiation and related harms. Further research is needed to validate findings and inform future approaches to preventing entry into drug injecting.

Model Research On Synthesis Of Al2O3-C Layers By MOCVD

Directory of Open Access Journals (Sweden)

Sawka A.

2015-06-01

Full Text Available These are model studies whose aim is to obtain information that would allow development of new technology for synthesizing monolayers of Al2O3-C with adjusted microstructure on cemented carbides. The Al2O3-C layer will constitute an intermediate layer on which the outer layer of Al2O3 without carbon is synthesized. The purpose of the intermediate layer is to block the cobalt diffusion to the synthesized outer layer of Al2O3 and to stop the diffusion of air oxygen to the substrate during the synthesis of the outer layer. This layer should be thin, continuous, dense and uniform in thickness.

Tetra-methyl substituted copper (II) phthalocyanine as a hole injection enhancer in organic light-emitting diodes

Energy Technology Data Exchange (ETDEWEB)

Wang, Yu-Long; Xu, Jia-Ju; Lin, Yi-Wei; Chen, Qian; Shan, Hai-Quan; Xu, Zong-Xiang, E-mail: xu.zx@sustc.edu.cn, E-mail: val.roy@cityu.edu.hk [Department of Chemistry, South University of Science and Technology of China, Shenzhen, Guangdong, P. R. China, 518055 (China); Yan, Yan; Roy, V. A. L., E-mail: xu.zx@sustc.edu.cn, E-mail: val.roy@cityu.edu.hk [Department of Physics and Materials Science, City University of Hong Kong, Hong Kong SAR (Hong Kong)

2015-10-15

We have enhanced hole injection and lifetime in organic light-emitting diodes (OLEDs) by incorporating the isomeric metal phthalocyanine, CuMePc, as a hole injection enhancer. The OLED devices containing CuMePc as a hole injection layer (HIL) exhibited higher luminous efficiency and operational lifetime than those using a CuPc layer and without a HIL. The effect of CuMePc thickness on device performance was investigated. Atomic force microscope (AFM) studies revealed that the thin films were smooth and uniform because the mixture of CuMePc isomers depressed crystallization within the layer. This may have caused the observed enhanced hole injection, indicating that CuMePc is a promising HIL material for highly efficient OLEDs.

Tetra-methyl substituted copper (II phthalocyanine as a hole injection enhancer in organic light-emitting diodes

Directory of Open Access Journals (Sweden)

Yu-Long Wang

2015-10-01

Full Text Available We have enhanced hole injection and lifetime in organic light-emitting diodes (OLEDs by incorporating the isomeric metal phthalocyanine, CuMePc, as a hole injection enhancer. The OLED devices containing CuMePc as a hole injection layer (HIL exhibited higher luminous efficiency and operational lifetime than those using a CuPc layer and without a HIL. The effect of CuMePc thickness on device performance was investigated. Atomic force microscope (AFM studies revealed that the thin films were smooth and uniform because the mixture of CuMePc isomers depressed crystallization within the layer. This may have caused the observed enhanced hole injection, indicating that CuMePc is a promising HIL material for highly efficient OLEDs.

Turbulent shear control with oscillatory bubble injection

International Nuclear Information System (INIS)

Park, Hyun Jin; Oishi, Yoshihiko; Tasaka, Yuji; Murai, Yuichi; Takeda, Yasushi

2009-01-01

It is known that injecting bubbles into shear flow can reduce the frictional drag. This method has advantages in comparison to others in simplicity of installation and also in environment. The amount of drag reduction by bubbles depends on the void fraction provided in the boundary layer. It means, however, that certain power must be consumed to generate bubbles in water, worsening the total power-saving performance. We propose oscillatory bubble injection technique to improve the performance in this study. In order to prove this idea of new type of drag reduction, velocity vector field and shear stress profile in a horizontal channel flow are measured by ultrasonic velocity profiler (UVP) and shear stress transducer, respectively. We measure the gas-liquid interface from the UVP signal, as well. This compound measurement with different principles leads to deeper understanding of bubble-originated drag reduction phenomena, in particular for unsteady process of boundary layer alternation. At these experiments, the results have demonstrated that the intermittency promotes the drag reduction more than normal continuous injection for the same void fraction supplied.

Disturbances to Air-Layer Skin-Friction Drag Reduction at High Reynolds Numbers

Science.gov (United States)

Dowling, David; Elbing, Brian; Makiharju, Simo; Wiggins, Andrew; Perlin, Marc; Ceccio, Steven

2009-11-01

Skin friction drag on a flat surface may be reduced by more than 80% when a layer of air separates the surface from a flowing liquid compared to when such an air layer is absent. Past large-scale experiments utilizing the US Navy's Large Cavitation Channel and a flat-plate test model 3 m wide and 12.9 m long have demonstrated air layer drag reduction (ALDR) on both smooth and rough surfaces at water flow speeds sufficient to reach downstream-distance-based Reynolds numbers exceeding 100 million. For these experiments, the incoming flow conditions, surface orientation, air injection geometry, and buoyancy forces all favored air layer formation. The results presented here extend this prior work to include the effects that vortex generators and free stream flow unsteadiness have on ALDR to assess its robustness for application to ocean-going ships. Measurements include skin friction, static pressure, airflow rate, video of the flow field downstream of the injector, and profiles of the flowing air-water mixture when the injected air forms bubbles, when it is in transition to an air layer, and when the air layer is fully formed. From these, and the prior measurements, ALDR's viability for full-scale applications is assessed.

Growing imbedded Ni3C-rich layer with sharp interfaces by means of ion beam mixing of C/Ni layers

International Nuclear Information System (INIS)

Barna, Arpad; Kotis, Laszlo; Labar, Janos; Sulyok, Attila; Toth, Attila L; Menyhard, Miklos; Panjan, Peter

2011-01-01

C/Ni bilayers of various layer thicknesses (20-40 nm) were ion bombarded using Ga + and Ni + projectiles of energies 20 and 30 keV. Ion bombardment resulted in the growth of a Ni 3 C rich layer with the following features: (a) sharp carbon/Ni 3 C rich layer interface, (b) the amount of Ni 3 C produced by the irradiation proportional to the square root of the fluence and dependent on the type of projectile, (c) good correlation between the distribution of vacancies produced by the ion bombardment and the distribution of Ni 3 C. The formation of the metastable Ni 3 C compound was explained by a vacancy-assisted process. The sharp interface is the consequence of a relaxation process removing the intermixed Ni from the carbon layer. The square root of fluence dependence of the thickness of the Ni 3 C-rich layer can be explained by a usual diffusion equation considering moving boundaries.

Experiment data report for Semiscale Mod-1 Test S-05-3 (alternate ECC injection test)

International Nuclear Information System (INIS)

Feldman, E.M.; Patton, M.L. Jr.; Sackett, K.E.

1977-03-01

Recorded test data are presented for Test S-05-3 of the Semiscale Mod-1 alternate ECC injection test series. These tests are among several Semiscale Mod-1 experiments conducted to investigate the thermal and hydraulic phenomena accompanying a hypothesized loss-of-coolant accident in a pressurized water reactor (PWR) system. Test S-05-3 was conducted from initial conditions of 2263 psia and 545 0 F to investigate the response of the Semiscale Mod-1 system to a depressurization and reflood transient following a simulated double-ended offset shear of the cold leg broken loop piping. During the test, cooling water was injected into the cold leg sides of the intact and broken loops and into the vessel upper plenum to simulate emergency core coolant injection in a PWR. For Test S-05-3, specifically the effects of upper plenum coolant injection on core thermal and system response were being investigated

Influence of PEDOT:PSS on the effectiveness of barrier layers prepared by atomic layer deposition in organic light emitting diodes

Energy Technology Data Exchange (ETDEWEB)

Wegler, Barbara, E-mail: barbara.wegler@siemens.com [Siemens AG, Corporate Technology, Guenther-Scharowsky-Strasse 1, 91058 Erlangen, Germany and Center for Medical Physics and Engineering, University of Erlangen-Nuremberg, Henkestrasse 91, 91052 Erlangen (Germany); Schmidt, Oliver [Siemens AG, Corporate Technology, Guenther-Scharowsky-Strasse 1, 91058 Erlangen (Germany); Hensel, Bernhard [Center for Medical Physics and Engineering, University of Erlangen-Nuremberg, Henkestrasse 91, 91052 Erlangen (Germany)

2015-01-15

Organic light emitting diodes (OLEDs) are well suited for energy saving lighting applications, especially when thinking about highly flexible and large area devices. In order to avoid the degradation of the organic components by water and oxygen, OLEDs need to be encapsulated, e.g., by a thin sheet of glass. As the device is then no longer flexible, alternative coatings are required. Atomic layer deposition (ALD) is a very promising approach in this respect. The authors studied OLEDs that were encapsulated by 100 nm Al{sub 2}O{sub 3} deposited by ALD. The authors show that this coating effectively protects the active surface area of the OLEDs from humidity. However, secondary degradation processes still occur at sharp edges of the OLED stack where the extremely thin encapsulation layer does not provide perfect coverage. Particularly, the swelling of poly(3,4-ethylenedioxythiophene) mixed with poly(styrenesulfonate), which is a popular choice for the planarization of the bottom electrode and at the same time acts as a hole injection layer, affects the effectiveness of the encapsulation layer.

Radioautography of the central nervous system and pituitary after 3H steroid hormones injection into different mammals

International Nuclear Information System (INIS)

Warembourg, M.

1977-01-01

The central nervous system and pituitary of various mammals were examined by radioautography after injection of different tritiated steroid hormones. After injection of 3 H estradiol into ovariectomized mice, radioautograms revealed a significant labelling in cells of the amygdala, the bed nucleus of the stria terminalis, the nucleus preopticus medialis, the nuclei arcuatus and ventro-medialis. After injection of 3 H testosterone into castrated rats, the central nervous system and the anterior pituitary contained labelled cells. In the hypothalamus, the distribution pattern of androgen-neurons appears to be similar from the estrogen-neuron areas. After injection of 3 H progesterone into castrated estrogen-primed guinea-pigs, labelled neurons have been in the regions of nucleus arcuatus and nucleus preopticus suprachiasmaticus. After injection of 3 H corticosterone into adrenalectomized male rats, radioactivity was found to be selectively concentrated in neurons of septum, hippocampal complex indusium griseum, amygdala and in certain areas of the cortex. Most of the silver grains were localized in the nuclei of labelled cells. On the other hand, after injection of 3 H dexamethasone radioactivity concentration was high in the medial basal hypothalamus, in the anterior pituitary and in the pineal gland. Differences appear to exist in the topographic distribution of dexamethasone and corticosterone-concentrating cells [fr

Organic Light-Emitting Diodes with Magnesium Doped CuPc as an Efficient Electron Injection Layer

International Nuclear Information System (INIS)

Jun-Song, Cao; Min, Guan; Guo-Hua, Cao; Yi-Ping, Zeng; Jin-Min, Li; Da-Shan, Qin

2008-01-01

Bright organic electroluminescent devices are developed using a metal-doped organic layer intervening between the cathode and the emitting layer. The typical device structure is a glass substrate/indium-tin oxide (ITO)/copper phthalocyanine(CuPc)/N,N-bis-(1-naphthl)-diphenyl-1, 1'-biphenyl-4,4'-diamine (NPB)/Tris(8-quinolinolato) alu-minum(Alq 3 )/Mg-doped CuPc/Ag. At a driving voltage of 11 V, the device with a layer of Mg-doped CuPc (1:2 in weight) shows a brightness of 4312 cd/m 2 and a current efficiency of 2.52 cd/A, while the reference device exhibits 514 cd/m 2 and 1.25 cd/A

Microbubble drag reduction in liquid turbulent boundary layers

International Nuclear Information System (INIS)

Merkle, C.L.; Deutsch, S.

1992-01-01

The interactions between a dense cloud of small bubbles and a liquid turbulent boundary layer are reviewed on the basis of available experimental observations to understand and quantify their capability for reducing skin friction. Gas bubbles are generally introduced into the boundary layer by injection through a porous surface or by electrolysis. After injection, the bubbles stay near the wall in boundary-layer-like fashion giving rise to strong gradients in both velocity and gas concentration. In general, the magnitude of the skin friction reduction increases as the volume of bubbles in the boundary layer is increased until a maximum skin friction reduction of typically 80-90% of the undisturbed skin friction level is reached. The volumetric gas flow required for this maximum is nominally equal to the volume flow of the liquid in the boundary layer. Bubble size estimates indicate that in most microbubble experiments the bubbles have been intermediate in size between the inner and outer scales of the undisturbed boundary layer. Additional studies with other nondimensional bubble sizes would be useful. However, the bubble size is most likely controlled by the injection process, and considerably different conditions would be required to change this ratio appreciably. The trajectories of the bubble clouds are primarily determined by the random effects of turbulence and bubble-bubble interactions. The effects of buoyancy represent a weaker effect. The trajectories are unlike the deterministic trajectory of an individual bubble in a time-averaged boundary layer. Bubbles are most effective in high speed boundary layers and, for the bubble sizes tested to date, produce an effect that persists for some on hundred boundary layer thicknesses. Modeling suggests that microbubbles reduce skin friction by increasing the turbulence Reynolds number in the buffer layer in a manner similar to polymers

Contact engineering for efficient charge injection in organic transistors with low-cost metal electrodes

Science.gov (United States)

Panigrahi, D.; Kumar, S.; Dhar, A.

2017-10-01

Controlling charge injection at the metal-semiconductor interface is very crucial for organic electronic devices in general as it can significantly influence the overall device performance. Herein, we report a facile, yet efficient contact modification approach, to enhance the hole injection efficiency through the incorporation of a high vacuum deposited TPD [N,N'-Bis(3-methylphenyl)-N,N'-diphenylbenzidine] interlayer between the electrodes and the active semiconducting layer. The device performance parameters such as mobility and on/off ratio improved significantly after the inclusion of the TPD buffer layer, and more interestingly, the devices with cost effective Ag and Cu electrodes were able to exhibit a superior device performance than the typically used Au source-drain devices. We have also observed that this contact modification technique can be even more effective than commonly used metal oxide interface modifying layers. Our investigations demonstrate the efficacy of the TPD interlayer in effectively reducing the interfacial contact resistance through the modification of pentacene energy levels, which consequently results in the substantial improvement in the device performances.

Excitation spectra and forward injection electroluminescence of Er/sup 3+/ ions in ZnS

International Nuclear Information System (INIS)

Jiaqi, Y.; Tianren, Z.; Wenlian, L.

1985-01-01

Trivalent rare earth ions (RE/sup 3+/) are efficient luminescent centers for electroluminescence (EL) of thin films of II-VI compounds, which are promising display materials and attract more and more attention. The mechanism of all EL devices of RE/sup 3+/ available so far is hot electron impact excitation. Based on the analysis of excitation spectra of RE/sup 3+/ in ZnS, the authors have pointed out the possibility of a new type of EL of RE/sup 3+/ - forward injection EL, which have potential of reducing operation voltage and raising efficiency. The forward injection EL of RE/sup 3+/ has been observed and experimentally proven in ZnS:Er/sup 3+/ diode for the first time

A non-magnetic spacer layer effect on spin layers (7/2,3) in a bi-layer ferromagnetic dendrimer structure: Monte Carlo study

Science.gov (United States)

Jabar, A.; Tahiri, N.; Bahmad, L.; Benyoussef, A.

2016-11-01

A bi-layer system consisting of layers of spins (7/2, 3) in a ferromagnetic dendrimer structure, separated by a non-magnetic spacer, is studied by Monte Carlo simulations. The effect of the RKKY interactions is investigated and discussed for such system. It is shown that the magnetic properties in the two magnetic layers depend strongly on the thickness of the magnetic and non-magnetic layers. The total magnetizations and susceptibilities are studied as a function of the reduced temperature. The effect of the reduced exchange interactions as well as the reduced crystal field is outlined. On other hand, the critical temperature is discussed as a function of the magnetic layer values. To complete this study we presented and discussed the magnetic hysteresis cycles.

Universal diffusion-limited injection and the hook effect in organic thin-film transistors

Science.gov (United States)

Liu, Chuan; Huseynova, Gunel; Xu, Yong; Long, Dang Xuan; Park, Won-Tae; Liu, Xuying; Minari, Takeo; Noh, Yong-Young

2016-01-01

The general form of interfacial contact resistance was derived for organic thin-film transistors (OTFTs) covering various injection mechanisms. Devices with a broad range of materials for contacts, semiconductors, and dielectrics were investigated and the charge injections in staggered OTFTs was found to universally follow the proposed form in the diffusion-limited case, which is signified by the mobility-dependent injection at the metal-semiconductor interfaces. Hence, real ohmic contact can hardly ever be achieved in OTFTs with low carrier concentrations and mobility, and the injection mechanisms include thermionic emission, diffusion, and surface recombination. The non-ohmic injection in OTFTs is manifested by the generally observed hook shape of the output conductance as a function of the drain field. The combined theoretical and experimental results show that interfacial contact resistance generally decreases with carrier mobility, and the injection current is probably determined by the surface recombination rate, which can be promoted by bulk-doping, contact modifications with charge injection layers and dopant layers, and dielectric engineering with high-k dielectric materials. PMID:27440253

Degree of Agreement between Cardiovascular Risk Stratification Tools.

Science.gov (United States)

Garcia, Guilherme Thomé; Stamm, Ana Maria Nunes de Faria; Rosa, Ariel Córdova; Marasciulo, Antônio Carlos; Marasciulo, Rodrigo Conill; Battistella, Cristian; Remor, Alexandre Augusto de Costa

2017-05-01

Cardiovascular disease (CVD) is the leading cause of morbidity and mortality in Brazil, and primary prevention care may be guided by risk stratification tools. The Framingham (FRS) and QRISK-2 (QRS) risk scores estimate 10-year overall cardiovascular risk in asymptomatic individuals, but the instrument of choice may lead to different therapeutic strategies. To evaluate the degree of agreement between FRS and QRS in 10-year overall cardiovascular risk stratification in disease-free individuals. Cross-sectional, observational, descriptive and analytical study in a convenience sample of 74 individuals attending the outpatient care service of a university hospital in Brazil between January 2014 and January 2015. After application of FRS and QRS, patients were classified in low/moderate risk (Brasil, e a prevenção primária pode ser direcionada com ferramentas que estratificam o risco. Os escores de Framingham (ERF) e QRISK-2 (ERQ) estimam o risco cardiovascular (RCV) global em 10 anos em indivíduos assintomáticos, mas a escolha do instrumento pode implicar em terapêuticas distintas. Observar o grau de concordância entre o ERF e o ERQ, na estratificação do risco cardiovascular global em 10 anos, nos indivíduos livres da doença. Estudo transversal, observacional, descritivo e analítico, com uma amostra de conveniência de 74 indivíduos, atendidos em um ambulatório de ensino de um hospital universitário brasileiro, no sul do país, de janeiro de 2014 a janeiro de 2015. O ERF e o ERQ foram aplicados nos pacientes, que foram classificados em baixo/moderado (superior no ERF que no ERQ (33,7% vs 21,6%), sendo identificado efeito sinérgico do gênero masculino com hipertensão arterial sistêmica nas duas ferramentas, e com faixa etária geriátrica no ERQ (p < 0,05) nesse estrato de risco. O índice de concordância Kappa entre os dois escores foi igual a 0,519 (IC95% = 0,386-0,652; p < 0,001). Houve concordância moderada entre o ERF e o ERQ, na estimativa de

Preparation of ultra-thin and high-quality WO{sub 3} compact layers and comparision of WO{sub 3} and TiO{sub 2} compact layer thickness in planar perovskite solar cells

Energy Technology Data Exchange (ETDEWEB)

Zhang, Jincheng; Shi, Chengwu, E-mail: shicw506@foxmail.com; Chen, Junjun; Wang, Yanqing; Li, Mingqian

2016-06-15

In this paper, the ultra-thin and high-quality WO{sub 3} compact layers were successfully prepared by spin-coating-pyrolysis method using the tungsten isopropoxide solution in isopropanol. The influence of WO{sub 3} and TiO{sub 2} compact layer thickness on the photovoltaic performance of planar perovskite solar cells was systematically compared, and the interface charge transfer and recombination in planar perovskite solar cells with TiO{sub 2} compact layer was analyzed by electrochemical impedance spectroscopy. The results revealed that the optimum thickness of WO{sub 3} and TiO{sub 2} compact layer was 15 nm and 60 nm. The planar perovskite solar cell with 15 nm WO{sub 3} compact layer gave a 9.69% average and 10.14% maximum photoelectric conversion efficiency, whereas the planar perovskite solar cell with 60 nm TiO{sub 2} compact layer achieved a 11.79% average and 12.64% maximum photoelectric conversion efficiency. - Graphical abstract: The planar perovskite solar cell with 15 nm WO{sub 3} compact layer gave a 9.69% average and 10.14% maximum photoelectric conversion efficiency, whereas the planar perovskite solar cell with 60 nm TiO{sub 2} compact layer achieved a 11.79% average and 12.64% maximum photoelectric conversion efficiency. Display Omitted - Highlights: • Preparation of ultra-thin and high-quality WO{sub 3} compact layers. • Perovskite solar cell with 15 nm-thick WO{sub 3} compact layer achieved PCE of 10.14%. • Perovskite solar cell with 60 nm-thick TiO{sub 2} compact layer achieved PCE of 12.64%.

Improved performance of quantum dot light emitting diode by modulating electron injection with yttrium-doped ZnO nanoparticles

Science.gov (United States)

Li, Jingling; Guo, Qiling; Jin, Hu; Wang, Kelai; Xu, Dehua; Xu, Yongjun; Xu, Gang; Xu, Xueqing

2017-10-01

In a typical light emitting diode (QD-LED), with ZnO nanoparticles (NPs) serving as the electron transport layer (ETL) material, excessive electron injection driven by the matching conduction band maximum (CBM) between the QD and this oxide layer usually causes charge imbalance and degrades the device performance. To address this issue, the electronic structure of ZnO NPs is modified by the yttrium (Y) doping method. We demonstrate that the CBM of ZnO NPs has a strong dependence on the Y-doping concentration, which can be tuned from 3.55 to 2.77 eV as the Y doping content increases from 0% to 9.6%. This CBM variation generates an enlarged barrier between the cathode and this ZnO ETL benefits from the modulation of electron injection. By optimizing electron injection with the use of a low Y-doped (2%) ZnO to achieve charge balance in the QD-LED, device performance is significantly improved with maximum luminance, peak current efficiency, and maximal external quantum efficiency increase from 4918 cd/m2, 11.3 cd/A, and 4.5% to 11,171 cd/m2, 18.3 cd/A, and 7.3%, respectively. This facile strategy based on the ETL modification enriches the methodology of promoting QD-LED performance.

Distinct patterns of corticogeniculate feedback to different layers of the lateral geniculate nucleus

Directory of Open Access Journals (Sweden)

Ichida JM

2014-09-01

Full Text Available Jennifer M Ichida,1 Julia A Mavity-Hudson,2 Vivien A Casagrande1–3 1Department of Psychology, 2Department of Cell and Developmental Biology, 3Department of Ophthalmology and Visual Sciences, Vanderbilt University, Nashville, TN, USA Abstract: In primates, feedforward visual pathways from retina to lateral geniculate nucleus (LGN are segregated to different layers. These layers also receive strong reciprocal feedback pathways from cortex. The degree to which feedforward streams in primates are segregated from feedback streams remains unclear. Here, we asked whether corticogeniculate cells that innervate the magnocellular (M, parvocellular (P, and koniocellular (K layers of the LGN in the prosimian primate bush baby (Otolemur garnettii can be distinguished based on either the laminar distribution or morphological characteristics of their axons and synaptic contacts in LGN, or on their cell body position, size, and dendritic distribution in cortex. Corticogeniculate axons and synapses were labeled anterogradely with biotinylated dextran injections in layer 6 of cortex. Corticogeniculate cell bodies were first labeled with fluorescent dextran injections limited to individual M, P, or K LGN layers and then filled with biotinylated Lucifer yellow. Results showed that feedback to the M or P LGN layers arises from cells with dendrites primarily confined to cortical layer 6 and axons restricted to either M or P LGN layers, but not both. Feedback to K LGN layers arises from cells: 1 whose dendrites distribute rather evenly across cortical layers 5 and 6; 2 whose dendrites always extend into layer 4; and 3 whose axons are never confined to K layers but always overlap with either P or M layers. Corticogeniculate axons also showed distributions that were retinotopically precise based on known receptive field sizes of layer 6 cells, and these axons mainly made synapses with glutamatergic projection neurons in the LGN in all layers. Taken together with prior

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)

Subcutaneous injection of 99mTc pertechnetate at acupuncture points K-3 and B-60

International Nuclear Information System (INIS)

Wu Chung-Chieng; Jong Shiang-Bin; Lin Chun-Ching; Chen Min-Fen; Chen Jong-Rern; Chung Chieng.

1990-01-01

The acupuncture points are known to be morphologically related to the nerves and vessels. Yet the physiological role of blood vessels in the formation of acupuncture points remains unknown. With subcutaneous injection of 99m Tc pertechnetate at the acupuncture points K-3 and B-60 and with intra-acupuncture point injection of 99m Tc pertechnetate at K-3 and B-60, a lower-limb venography like what was obtained by intravenous injection of 99m Tc macroaggregated albumin was demonstrated in the present study. It seems that some acupuncture points do play a role in drainage of tissue fluid from soft tissue into the veins. (author)

White OLED with high stability and low driving voltage based on a novel buffer layer MoOx

Energy Technology Data Exchange (ETDEWEB)

Jiang Xueyin [School of Materials Science and Engineering, Shanghai University, Jiading, Shanghai 201800 (China); Zhang Zhilin [School of Materials Science and Engineering, Shanghai University, Jiading, Shanghai 201800 (China); Cao Jin [Key Laboratory of Advanced Display and System Application, Ministry of Education, Shanghai University, Shanghai 200072 (China); Khan, M A [School of Materials Science and Engineering, Shanghai University, Jiading, Shanghai 201800 (China); Khizar-ul-Haq [School of Materials Science and Engineering, Shanghai University, Jiading, Shanghai 201800 (China); Zhu Wenqing [School of Materials Science and Engineering, Shanghai University, Jiading, Shanghai 201800 (China)

2007-09-21

White organic light emitting diodes (WOLEDs) with copper phthalocyanine (CuPc), 4,4',4-prime-tris(N-3-methylphenyl-N-phenyl-amino) triphenylamine (m-MTDATA), tungsten oxide (WO{sub 3}) and molybdenum oxide (MoOx) as buffer layers have been investigated. The MoOx based device shows superior performance with low driving voltage, high power efficiency and much longer lifetime than those with other buffer layers. For the Cell using MoOx as buffer layer and 4,7-diphenyl-1,10-phenanthroline (Bphen) as electron transporting layer (ETL), at the luminance of 1000 cd m{sup -2}, the driving voltage is 4.9 V, which is 4.2 V, 2 V and 0.7 V lower than that of the devices using CuPc (Cell-CuPc), m-MTDATA (Cell-m-MTDATA) and WO{sub 3} (Cell-WO{sub 3}) as buffer layers, respectively. Its power efficiency is 7.67 Lm W{sup -1}, which is 2.37 times higher than that of Cell-CuPc and a little higher than that of Cell-m-MTDATA. The projected half-life under the initial luminance of 100 cd m{sup -2} is 55 260 h, which is more than 4.6 times longer than that of Cell-m-MTDATA and Cell-CuPc. The superior performance of Cell-MoOx is attributed to its high hole injection ability and the stable interface between MoOx and organic material. The work function of MoOx has been measured by the contact potential difference method. The J-V curves of 'hole-only' devices indicate that a small hole injection barrier between MoOx/N,'-bis(naphthalene-1-y1)-N, N'-bis(phenyl)-benzidine (NPB) leads to a strong hole injection, resulting in a low driving voltage and a high stability.

3D LDV Measurements in Oscillatory Boundary Layers

Science.gov (United States)

Mier, J. M.; Garcia, M. H.

2012-12-01

The oscillatory boundary layer represents a particular case of unsteady wall-bounded flows in which fluid particles follow a periodic sinusoidal motion. Unlike steady boundary layer flows, the oscillatory flow regime and bed roughness character change in time along the period for every cycle, a characteristic that introduces a high degree of complexity in the analysis of these flows. Governing equations can be derived from the general Navier-Stokes equations for the motion of fluids, from which the exact solution for the laminar oscillatory boundary layer is obtained (also known as the 2nd Stokes problem). No exact solution exists for the turbulent case, thus, understanding of the main flow characteristics comes from experimental work. Several researchers have reported experimental work in oscillatory boundary layers since the 1960's; however, larger scale facilities and the development of newer measurement techniques with improved temporal and spatial resolution in recent years provides a unique opportunity to achieve a better understanding about this type of flows. Several experiments were performed in the Large Oscillatory Water and Sediment Tunnel (LOWST) facility at the Ven Te Chow Hydrosystems Laboratory, for a range of Reynolds wave numbers between 6x10^4 3D Laser Doppler Velocimetry (LDV) system was used to measure instantaneous flow velocities with a temporal resolution up to ~ 1,000 Hz. It was mounted on a 3-axis traverse with a spatial resolution of 0.01 mm in all three directions. The closest point to the bottom was measured at z = 0.2 mm (z+ ≈ 4), which allowed to capture boundary layer features with great detail. In order to achieve true 3D measurements, 2 probes were used on a perpendicular configuration, such that u and w components were measured from a probe on the side of the flume and v component was measured from a probe pointing down through and access window on top of the flume. The top probe was submerged in a water container, such that the

Particle fuelling for long pulse with standard gas puff and supersonic pulsed gas injection

International Nuclear Information System (INIS)

Bucalossi, J.; Tsitrone, E.; Martin, G.

2003-01-01

In addition to the standard gas puff and to the technically complex pellet injection, a novel intermediate method, based on the injection of a supersonic high density cloud of neutrals, has been recently implemented on the Tore Supra tokamak. Fuelling efficiency, in the 30-50% range are found while it lies in the 10-20% range for the gas puff. It is not sensitive to the plasma density and to the additional heating. According to modelling, the increased efficiency is attributed to the very short injection duration compared to the particle confinement time and to the strong cooling of the plasma edge resulting from the massive injection of matter. A feedback loop on the frequency of the injector has been successfully implemented to control the plasma density. In long pulse experiments (>200s), wall saturation has not been reached. Gas puffing rate was typically around 1 Pa.m 3 s -1 while dynamic wall retention around 0.6 Pa.m 3 s -1 . Co-deposited carbon layer could trap such large amounts of gas. A discharge fuelled by supersonic pulsed gas injections exhibits lower wall retention than a gas puff fuelled discharge. (author)

Therapeutic hip injections: Is the injection volume important?

International Nuclear Information System (INIS)

Young, R.; Harding, J.; Kingsly, A.; Bradley, M.

2012-01-01

Aim: To assess whether an increased volume of local anaesthetic injection given with intra-articular steroids improves symptom relief in osteoarthritis of the hip. Materials and methods: One hundred and ten patients with hip osteoarthritis were randomized into two groups (A and B). All patients were given 40 mg triamcinolone and 2 ml bupivicaine, and patients from group B were also given 6 ml of sterile water for injection. Change in WOMAC (Western Ontario and McMaster University Osteoarthritis Index Version 3.1) scores from baseline to 3 months were calculated and assessed for clinical and statistical significance. The patients were assessed for pain at 2 weekly intervals using the Oxford pain chart. Results: Patients from group B showed some reduction in stiffness (7%) and improved function (3%) compared with group A, and there were more clinical responders in these two categories. However, there was no significant statistical or clinical difference in WOMAC scores between the two groups at 3 months. There was also no statistical difference in pain symptoms between the two groups during the study period, measured at 2 weekly intervals. One hundred and two patients reached the study endpoint; eight patients who had bilateral hip injections were subsequently included in the analysis, and these patients did not alter the findings significantly. Conclusions: Published total injection volumes used for treating osteoarthritis of the hip with intra-articular steroids vary from 3 to 12 ml. The present study has shown that there is no detriment to using a larger volume of injectate, and recommends that practitioners use total volumes between 3 and 9 ml.

Therapeutic hip injections: Is the injection volume important?

Energy Technology Data Exchange (ETDEWEB)

Young, R., E-mail: russell.young@gwh.nhs.uk [Department of Radiology, Great Western Hospital, Swindon (United Kingdom); Harding, J. [Department of Radiology, University Hospital Coventry, Coventry (United Kingdom); Kingsly, A. [Department of Mathematics and Statistics, Bristol Institue of Technology, University of the West of England, Bristol (United Kingdom); Bradley, M. [Department of Radiology, Southmead Hospital, Bristol (United Kingdom)

2012-01-15

Aim: To assess whether an increased volume of local anaesthetic injection given with intra-articular steroids improves symptom relief in osteoarthritis of the hip. Materials and methods: One hundred and ten patients with hip osteoarthritis were randomized into two groups (A and B). All patients were given 40 mg triamcinolone and 2 ml bupivicaine, and patients from group B were also given 6 ml of sterile water for injection. Change in WOMAC (Western Ontario and McMaster University Osteoarthritis Index Version 3.1) scores from baseline to 3 months were calculated and assessed for clinical and statistical significance. The patients were assessed for pain at 2 weekly intervals using the Oxford pain chart. Results: Patients from group B showed some reduction in stiffness (7%) and improved function (3%) compared with group A, and there were more clinical responders in these two categories. However, there was no significant statistical or clinical difference in WOMAC scores between the two groups at 3 months. There was also no statistical difference in pain symptoms between the two groups during the study period, measured at 2 weekly intervals. One hundred and two patients reached the study endpoint; eight patients who had bilateral hip injections were subsequently included in the analysis, and these patients did not alter the findings significantly. Conclusions: Published total injection volumes used for treating osteoarthritis of the hip with intra-articular steroids vary from 3 to 12 ml. The present study has shown that there is no detriment to using a larger volume of injectate, and recommends that practitioners use total volumes between 3 and 9 ml.

Quick Look Report of the SMART ECC injection performance test I3

Energy Technology Data Exchange (ETDEWEB)

Cho, Seok; Ko, Yong Ju; Cho, Young Il; Kim, Jeong Tak; Choi, Nam Hyun; Park, Choon Kyong; Kwon, Tae Soon; Lee, Sung Jae [KAERI, Daejeon (Korea, Republic of)

2010-12-15

The objective of this report is to describe test results of the Test I3 simulating the 2 inch SBLOCA of the SMART using the SWAT test facility. The Test I3 was performed to produce experimental data for the validation of the TASS/SMR-S thermal hydraulic analysis code, and to investigate the related thermal hydraulic phenomena in the down-comer region during the 2 inch SBLOCA of the safety inject line. The particular phenomena for the observation are ECC bypass and multi-dimensional flow characteristics to verify the effectiveness and performance of the safety injection system. In this report, the corresponding steady state test conditions, including initial and boundary conditions along with major measuring parameters, and related experimental results were described

New Algorithm to Enable Construction and Display of 3D Structures from Scanning Probe Microscopy Images Acquired Layer-by-Layer.

Science.gov (United States)

Deng, William Nanqiao; Wang, Shuo; Ventrici de Souza, Joao Francisco; Kuhl, Tonya L; Liu, Gang-Yu

2018-06-11

Scanning probe microscopy (SPM) such as atomic force microscopy (AFM) is widely known for high-resolution imaging of surface structures and nanolithography in two dimension (2D), which provides important physical insights in surface science and material science. This work reports a new algorithm to enable construction and display of layer-by-layer 3D structures from SPM images. The algorithm enables alignment of SPM images acquired during layer-by-layer deposition, removal of redundant features, and faithfully constructs the deposited 3D structures. The display uses a "see-through" strategy to enable the structure of each layer to be visible. The results demonstrate high spatial accuracy as well as algorithm versatility; users can set parameters for reconstruction and display as per image quality and research needs. To the best of our knowledge, this method represents the first report to enable SPM technology for 3D imaging construction and display. The detailed algorithm is provided to facilitate usage of the same approach in any SPM software. These new capabilities support wide applications of SPM that require 3D image reconstruction and display, such as 3D nanoprinting, and 3D additive and subtractive manufacturing and imaging.

Native SrTiO3 (001) surface layer from resonant Ti L2,3 reflectance spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Valvidares, Manuel; Huijben, Mark; Yu, Pu; Ramesh, Ramamoorthy; Kortright, Jeffrey

2010-11-03

We quantitatively model resonant Ti L2,3 reflectivity Rs,p(q, hn) from several SrTiO3 (001) single crystals having different initial surface preparations and stored in ambient conditions before and between measurements. All samples exhibit unexpected 300 K Rs(hn) - Rp(hn) anisotropy corresponding to weak linear dichroism and tetragonal distortion of the TiO6 octahedra indicating a surface layer with properties different from cubic SrTiO3. Oscillations in Rs(q) confirm a ubiquitous surface layer 2-3 nm thick that evolves over a range of time scales. Resonant optical constant spectra derived from Rs,p(hn) assuming a uniform sample are refined using a single surface layer to fit measured Rs(q). Differences in surface layer and bulk optical properties indicate that the surface is significantly depleted in Sr and enriched in Ti and O. While consistent with the tendency of SrTiO3 surfaces toward non-stoichiometry, this layer does not conform simply to existing models for the near surface region and apparently forms via room temperature surface reactions with the ambient. This new quantitative spectral modeling approach is generally applicable and has potential to study near-surface properties of a variety of systems with unique chemical and electronic sensitivities.

PIV measurement of turbulent bubbly mixing layer flow with polymer additives

International Nuclear Information System (INIS)

Ning, T; Guo, F; Chen, B; Zhang, X

2009-01-01

Based on experimental investigation of single-phase turbulent mixing layer flow with polymer additives, bubbly mixing layer was experimentally investigated by PIV. The velocity ratio between high and low speed is 4:1 and the Reynolds number based on the velocity difference of two steams and hydraulic diameter of the channel ranges is 73333. Gas bubbles with about 0.5% gas fraction were injected into pure water mixing layer with/without polymer additives from three different parts at the end of the splitter plate. The comparison between single phase and bubbly mixing layer shows clearly that the dynamic development of mixing layer is great influenced by the bubble injection. Similar with single phase, the Reynolds stress and vorticity still concentrate in a coniform area of central mixing flow field part and the width will increase with increasing the Reynolds number. Mean Reynolds stress will decrease with bubble injection in high Reynolds numbers and the decreasing of Reynolds stress with polymer additives is much more than pure water case.

Critical appraisal of 3-monthly paliperidone depot injections in the treatment of schizophrenia

Directory of Open Access Journals (Sweden)

Carpiniello B

2016-05-01

Full Text Available Bernardo Carpiniello, Federica Pinna Department of Public Health, Clinical and Molecular Medicine – Psychiatry Research Unit and Psychiatric Clinic, University Hospital, Cagliari, Italy Aims: Three-monthly injections of paliperidone palmitate (PP-3M represent a new and recently introduced long-acting antipsychotic therapeutic option. This review focuses on available data relating to the efficacy and safety of PP-3M and its position in the current therapeutic scenario.Method: An analysis of PubMed, Scopus, and ISI Web of Knowledge databases was conducted, and all available papers on PP-3M, including poster presentations, were selected and considered for the purpose of the present review. Findings: to date, three full papers have been published, the first, a Phase 1 randomized, open label study investigating the pharmacokinetics, safety, and tolerability of the drug; the second, a Phase 3 double blind study vs placebo focusing on efficacy and tolerability; and the last relating to the practical use of PP-3M. The five posters identified describe data reported in the above-cited papers. Overall, the pharmacokinetic findings obtained in these studies highlight the feasibility of administering PP-3M on a 3-monthly basis, subsequent to the administration of four 1-monthly injections of PP at doses 3.5 times higher than the stabilized dose of 1-monthly injections of PP (ie, 175, 300, 450, and 525 mgs. The published studies highlight a significantly longer time to relapse compared to placebo, and significantly better results compared to placebo for all secondary end-points (Positive and Negative Syndrome Scale, Clinical Global Impression-Severity Scale, Personal and Social Performance Scale scores, in addition to reasonably good safety and tolerability profiles.Conclusion: PP-3M emerges as a potential candidate for use as a first-line long-acting agent in the maintenance treatment of patients with schizophrenia. Further studies should however be

YBCO/manganite layered structures on NdGaO3 substrates

International Nuclear Information System (INIS)

Nurgaliev, T; Blagoev, B; Donchev, T; Miteva, S; Mozhaev, P B; Mozhaeva, J E; Ovsyannikov, G A; Kotelyanskii, I M; Jacobsen, C

2006-01-01

Results of deposition of YBa 2 Cu 3 O 7-x /CeO 2 /(La 0.7 Ca 0.3 MnO 3 or La 0.7 Sr 0.3 MnO 3 ) structures on the standard oriented and tilted ( 8 0 ) NdGaO 3 substrates and results of investigation of electrical parameters of YBa 2 Cu 3 O 7-x (YBCO) films in such structures are presented. The YBCO component of the structure exhibits lower value of the critical parameters in comparison with those of single YBCO films. The contribution of the magnetic layer to the microwave losses of the YBCO film in the layered structure is evaluated

On the AlxGa1-xN/AlyGa1-yN/AlxGa1-xN (x>y) p-electron blocking layer to improve the hole injection for AlGaN based deep ultraviolet light-emitting diodes

Science.gov (United States)

Chu, Chunshuang; Tian, Kangkai; Fang, Mengqian; Zhang, Yonghui; Li, Luping; Bi, Wengang; Zhang, Zi-Hui

2018-01-01

This work proposes the [0001] oriented AlGaN-based deep ultraviolet (DUV) light-emitting diode (LED) possessing a specifically designed p-electron blocking layer (p-EBL) to achieve the high internal quantum efficiency. Both electrons and holes can be efficiently injected into the active region by adopting the Al0.60Ga0.40N/Al0.50Ga0.50N/Al0.60Ga0.40N structured p-EBL, in which a p-Al0.50Ga0.50N layer is embedded into the p-EBL. Moreover, the impact of different thicknesses for the p-Al0.50Ga0.50N insertion layer on the hole and electron injections has also been investigated. Compared with the DUV LED with the bulk p-Al0.60Ga0.40N as the EBL, the proposed LED architectures improve the light output power if the thickness of the p-Al0.50Ga0.50N insertion layer is properly designed.

Probability theory for 3-layer remote sensing radiative transfer model: univariate case.

Science.gov (United States)

Ben-David, Avishai; Davidson, Charles E

2012-04-23

A probability model for a 3-layer radiative transfer model (foreground layer, cloud layer, background layer, and an external source at the end of line of sight) has been developed. The 3-layer model is fundamentally important as the primary physical model in passive infrared remote sensing. The probability model is described by the Johnson family of distributions that are used as a fit for theoretically computed moments of the radiative transfer model. From the Johnson family we use the SU distribution that can address a wide range of skewness and kurtosis values (in addition to addressing the first two moments, mean and variance). In the limit, SU can also describe lognormal and normal distributions. With the probability model one can evaluate the potential for detecting a target (vapor cloud layer), the probability of observing thermal contrast, and evaluate performance (receiver operating characteristics curves) in clutter-noise limited scenarios. This is (to our knowledge) the first probability model for the 3-layer remote sensing geometry that treats all parameters as random variables and includes higher-order statistics. © 2012 Optical Society of America

Laterally injected light-emitting diode and laser diode

Science.gov (United States)

Miller, Mary A.; Crawford, Mary H.; Allerman, Andrew A.

2015-06-16

A p-type superlattice is used to laterally inject holes into an III-nitride multiple quantum well active layer, enabling efficient light extraction from the active area. Laterally-injected light-emitting diodes and laser diodes can enable brighter, more efficient devices that impact a wide range of wavelengths and applications. For UV wavelengths, applications include fluorescence-based biological sensing, epoxy curing, and water purification. For visible devices, applications include solid state lighting and projection systems.

Microporous polymeric 3D scaffolds templated by the layer-by-layer self-assembly.

Science.gov (United States)

Paulraj, Thomas; Feoktistova, Natalia; Velk, Natalia; Uhlig, Katja; Duschl, Claus; Volodkin, Dmitry

2014-08-01

Polymeric scaffolds serve as valuable supports for biological cells since they offer essential features for guiding cellular organization and tissue development. The main challenges for scaffold fabrication are i) to tune an internal structure and ii) to load bio-molecules such as growth factors and control their local concentration and distribution. Here, a new approach for the design of hollow polymeric scaffolds using porous CaCO3 particles (cores) as templates is presented. The cores packed into a microfluidic channel are coated with polymers employing the layer-by-layer (LbL) technique. Subsequent core elimination at mild conditions results in formation of the scaffold composed of interconnected hollow polymer microspheres. The size of the cores determines the feature dimensions and, as a consequence, governs cellular adhesion: for 3T3 fibroblasts an optimal microsphere size is 12 μm. By making use of the carrier properties of the porous CaCO3 cores, the microspheres are loaded with BSA as a model protein. The scaffolds developed here may also be well suited for the localized release of bio-molecules using external triggers such as IR-light. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Movement of beta-irradiated epidermal basal cells to the spinous-granular layers in the absence of cell division

International Nuclear Information System (INIS)

Etoh, H.; Taguchi, Y.H.; Tabachnick, J.

1975-01-01

Guinea-pig epidermis was irradiated with 3000 rad of beta rays 1 hr after two injections of [ 3 H]thymidine 5 hr apart (labeled cells in S phase and G 2 phase) or 18 hr after injection (labeled early G 1 cells). In nonirradiated epidermis labeled basal cells divided within 24 hr with daughter cells remaining in the basal layer, and approximately 50 percent of the labeled cells moved into the spinal layer by the 3rd day. Cell division in nonirradiated epidermis diluted the number of silver grains/nucleus, and lightly labeled cells were found in the granular layer by day 7. Beta irradiation inhibited cell division but it did not slow the rate of transit (ca 8 days) of irradiated labeled cells from basal to granular layer, some of these remaining heavily labeled. Although cell division may play some role in upward movement of basal cells in normal epidermis detachment of a basal cell from the basement membrane and its transit to the granular layer is unimpaired in the absence of cell division. These findings suggest that some radioresistant metabolic function(s), not cell division, is responsible for upward movement of basal cells. (auth)

Distribution of [35S] taurine in mouse retina after intravitreal and intravascular injection

International Nuclear Information System (INIS)

Pourcho, R.G.

1977-01-01

The distribution of [ 35 S] taurine in mouse retinae was studied by autoradiographic techniques after either intravitreal or intravascular injection. The route of injection did not affect the final localization. The major sites of label accumulation were the outer nuclear layer, the inner nuclear layer, and Mueller cell processes adjacent to the vitreal surface. The distribution was consistent with the interpretation that taurine was localized within two cellular compartments of mouse retina, photoreceptor cells and Mueller cells. (author)

Sensitivity of the radiative forcing by stratospheric sulfur geoengineering to the amount and strategy of the SO2injection studied with the LMDZ-S3A model

Science.gov (United States)

Kleinschmitt, Christoph; Boucher, Olivier; Platt, Ulrich

2018-02-01

The enhancement of the stratospheric sulfate aerosol layer has been proposed as a method of geoengineering to abate global warming. Previous modelling studies found that stratospheric aerosol geoengineering (SAG) could effectively compensate for the warming by greenhouse gases on the global scale, but also that the achievable cooling effect per sulfur mass unit, i.e. the forcing efficiency, decreases with increasing injection rate. In this study we use the atmospheric general circulation model LMDZ with the sectional aerosol module S3A to determine how the forcing efficiency depends on the injected amount of SO2, the injection height, and the spatio-temporal pattern of injection. We find that the forcing efficiency may decrease more drastically for larger SO2 injections than previously estimated. As a result, the net instantaneous radiative forcing does not exceed the limit of -2 W m-2 for continuous equatorial SO2 injections and it decreases (in absolute value) for injection rates larger than 20 Tg S yr-1. In contrast to other studies, the net radiative forcing in our experiments is fairly constant with injection height (in a range 17 to 23 km) for a given amount of SO2 injected. Also, spreading the SO2 injections between 30° S and 30° N or injecting only seasonally from varying latitudes does not result in a significantly larger (i.e. more negative) radiative forcing. Other key characteristics of our simulations include a consequent stratospheric heating, caused by the absorption of solar and infrared radiation by the aerosol, and changes in stratospheric dynamics, with a collapse of the quasi-biennial oscillation at larger injection rates, which has impacts on the resulting spatial aerosol distribution, size, and optical properties. But it has to be noted that the complexity and uncertainty of stratospheric processes cause considerable disagreement among different modelling studies of stratospheric aerosol geoengineering. This may be addressed through detailed

Electrode quenching control for highly efficient CsPbBr3 perovskite light-emitting diodes via surface plasmon resonance and enhanced hole injection by Au nanoparticles

Science.gov (United States)

Meng, Yan; Wu, Xiaoyan; Xiong, Ziyang; Lin, Chunyan; Xiong, Zuhong; Blount, Ethan; Chen, Ping

2018-04-01

Compared to organic-inorganic hybrid metal halide perovskites, all-inorganic cesium lead halides (e.g, CsPbBr3) hold greater promise in being emissive materials for light-emitting diodes owing to their superior optoelectronic properties as well as their higher stabilities. However, there is still considerable potential for breakthroughs in the current efficiency of CsPbBr3 perovskite light-emitting diodes (PeLEDs). Electrode quenching is one of the main problems limiting the current efficiency of PeLEDs when poly(3,4-ethylenedioxythiophene): poly(styrenesulfonate) (PEDOT:PSS) is used as the hole injection layer. In this work, electrode quenching control was realized via incorporating Au NPs into PEDOT:PSS. As a result, the CsPbBr3 PeLEDs realized an improvement in maximum luminescence ranging from ˜2348 to ˜7660 cd m-2 (˜226% enhancement) and current efficiency from 1.65 to 3.08 cd A-1 (˜86% enhancement). Such substantial enhancement of the electroluminescent performance can be attributed to effective electrode quenching control at the PEDOT:PSS/CsPbBr3 perovskite interface via the combined effects of local surface plasma resonance coupling and enhanced hole transportation in the PEDOT:PSS layer by Au nanoparticles.

Atomic layer deposition and post-growth thermal annealing of ultrathin MoO3 layers on silicon substrates: Formation of surface nanostructures

Science.gov (United States)

Liu, Hongfei; Yang, Ren Bin; Yang, Weifeng; Jin, Yunjiang; Lee, Coryl J. J.

2018-05-01

Ultrathin MoO3 layers have been grown on Si substrates at 120 °C by atomic layer deposition (ALD) using molybdenum hexacarbonyl [Mo(CO)6] and ozone (O3) as the Mo- and O-source precursors, respectively. The ultrathin films were further annealed in air at Tann = 550-750 °C for 15 min. Scanning-electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy have been employed to evaluate the morphological and elemental properties as well as their evolutions upon annealing of the thin films. They revealed an interfacial SiOx layer in between the MoO3 layer and the Si substrate; this SiOx layer converted into SiO2 during the annealing; and the equivalent thickness of the MoO3 (SiO2) layer decreased (increased) with the increase in Tann. Particles with diameters smaller than 50 nm emerged at Tann = 550 °C and their sizes (density) were reduced (increased) by increasing Tann to 650 °C. A further increase of Tann to 750 °C resulted in telephone-cord-like MoO3 structures, initiated from isolated particles on the surface. These observations have been discussed and interpreted based on temperature-dependent atomic interdiffusions, surface evaporations, and/or melting of MoO3, which shed new light on ALD MoO3 towards its electronic applications.

Influence of Al{sub 2}O{sub 3} reflective layer under phosphor layer on luminance and luminous efficiency characteristics in alternating-current plasma display panel

Energy Technology Data Exchange (ETDEWEB)

Park, Choon-Sang [School of Electronics Engineering, College of IT Engineering, Kyungpook National University, Daegu (Korea, Republic of); Tae, Heung-Sik, E-mail: hstae@ee.knu.ac.kr [School of Electronics Engineering, College of IT Engineering, Kyungpook National University, Daegu (Korea, Republic of); Jung, Eun Young [Core Technology Lab., Corporate R and D Center, Samsung SDI Company Ltd., Cheonan (Korea, Republic of)

2013-11-29

This paper examines the optical and discharge characteristics of alternating-current plasma display panel when adopting the Al{sub 2}O{sub 3} reflective layer. The Al{sub 2}O{sub 3} reflective layer is deposited under the phosphor layer by using the screen-printing method. The resulting changes in the optical and discharge characteristics, including the power consumption, color temperature, luminance, luminous efficiency, scanning electron microscopy image, and reflectance, are then compared for both cases with and without Al{sub 2}O{sub 3} reflective layer. As a result of optimizing the thicknesses between the Al{sub 2}O{sub 3} and phosphor layers, the luminance and luminous efficiency are improved by about 17% and 7%, respectively. - Highlights: • We examine characteristics of plasma display panel when adopting reflective layer. • Al{sub 2}O{sub 3} reflective layer was deposited under the phosphor layer. • Al{sub 2}O{sub 3} reflective layer with flaky shape is very effective in enhancing luminance.

Nicolau Syndrome after Intramuscular Injection: 3 Cases

Directory of Open Access Journals (Sweden)

Seok-Kwun Kim

2012-05-01

Full Text Available Nicolau syndrome is a rare complication of intramuscular injection consisting of ischemicnecrosis of skin, soft tissue, and muscular tissue that arises locoregionally. The characteristicpattern is pain around the injection site, developing into erythema, a livedoid dermatitispatch, and necrosis of the skin, subcutaneous fat, and muscle tissue. Three patients wereinjected with drugs (diclofenac sodium, ketoprofen, meperidine for pain relief. Three patientscomplained of pain, and a skin lesion was observed, after which necrosis developed on theirbuttocks. Each patient underwent debridement and coverage. The wound healed uneventfully.We report three cases of Nicolau syndrome in the buttocks following diclofenac intramuscularinjection.

Experimental Results from a Flat Plate, Turbulent Boundary Layer Modified for the Purpose of Drag Reduction

Science.gov (United States)

Elbing, Brian R.

2006-11-01

Recent experiments on a flat plate, turbulent boundary layer at high Reynolds numbers (>10^7) were performed to investigate various methods of reducing skin friction drag. The methods used involved injecting either air or a polymer solution into the boundary layer through a slot injector. Two slot injectors were mounted on the model with one located 1.4 meters downstream of the nose and the second located 3.75 meters downstream. This allowed for some synergetic experiments to be performed by varying the injections from each slot and comparing the skin friction along the plate. Skin friction measurements were made with 6 shear stress sensors flush mounted along the stream-wise direction of the model.

Two-phase gas bubble-liquid boundary layer flow along vertical and inclined surfaces

International Nuclear Information System (INIS)

Cheung, F.B.; Epstein, M.

1985-01-01

The behavior of a two-phase gas bubble liquid boundary layer along vertical and inclined porous surfaces with uniform gas injection is investigated experimentally and analytically. Using argon gas and water as the working fluids, a photographical study of the two-phase boundary layer flow has been performed for various angles of inclination ranging from 45 0 to 135 0 and gas injection rates ranging from 0.01 to 0.1 m/s. An integral method has been employed to solve the system of equations governing the two-phase motion. The effects of the gas injection rate and the angle of inclination on the growth of the boundary layer have been determined

Subcutaneous injection of sup 99m Tc pertechnetate at acupuncture points K-3 and B-60

Energy Technology Data Exchange (ETDEWEB)

Wu Chung-Chieng; Jong Shiang-Bin; Lin Chun-Ching; Chen Min-Fen; Chen Jong-Rern (Kaohsiung Medical Coll., Taiwan (China)); Chung Chieng

1990-06-01

The acupuncture points are known to be morphologically related to the nerves and vessels. Yet the physiological role of blood vessels in the formation of acupuncture points remains unknown. With subcutaneous injection of {sup 99m}Tc pertechnetate at the acupuncture points K-3 and B-60 and with intra-acupuncture point injection of {sup 99m}Tc pertechnetate at K-3 and B-60, a lower-limb venography like what was obtained by intravenous injection of {sup 99m}Tc macroaggregated albumin was demonstrated in the present study. It seems that some acupuncture points do play a role in drainage of tissue fluid from soft tissue into the veins. (author).

Five second helium neutral beam injection using argon-frost cryopumping techniques

International Nuclear Information System (INIS)

Phillips, J.C.; Kellman, D.H.; Hong, R.; Kim, J.; Laughon, G.M.

1995-10-01

High power helium neutral beams for the heating of tokamak discharges can now be provided for 5 s by using argon cryopumping (of the helium gas) in the beamlines. A system has now been installed to deposit a layer of argon frost on the DIII-D neutral beam cryopanels, between tokamak injection pulses. The layer serves to trap helium on the cryopanels providing sufficient pumping speed for 5 s helium beam extraction. The argon frosting hardware is now present on two of four DIII-D neutral beamlines, allowing injection of up to 6 MW of helium neutral beams per discharge, with pulse lengths of up to 5 s. The argon frosting system is described, along with experimental results demonstrating its effectiveness as a method of economically extending the capabilities of cryogenic pumping panels to allow multi-second helium neutral beam injection

Soft-tissue tumor differentiation using 3D power Doppler ultrasonography with echo-contrast medium injection.

Science.gov (United States)

Chiou, Hong-Jen; Chou, Yi-Hong; Chen, Wei-Ming; Chen, Winby; Wang, Hsin-Kai; Chang, Cheng-Yen

2010-12-01

We aimed to evaluate the ability of 3-dimensional power Doppler ultrasonography to differentiate soft-tissue masses from blood flow and vascularization with contrast medium. Twenty-five patients (mean age, 44.1 years; range, 12-77 years) with a palpable mass were enrolled in this study. Volume data were acquired using linear and convex 3-dimensional probes and contrast medium injected manually by bolus. Data were stored and traced slice by slice for 12 slices. All patients were scanned by the same senior sonologist. The vascular index (VI), flow index (FI), and vascular-flow index (VFI) were automatically calculated after the tumor was completely traced. All tumors were later confirmed by pathology. The study included 8 benign (mean, 36.5 mL; range, 2.4-124 mL) and 17 malignant (mean, 319.4 mL; range, 9.9-1,179.6 mL) tumors. Before contrast medium injection, mean VI, FI and VFI were, respectively, 3.22, 32.26 and 1.07 in benign tumors, and 1.97, 29.33 and 0.67 in malignant tumors. After contrast medium injection, they were, respectively, 20.85, 37.33 and 8.52 in benign tumors, and 40.12, 41.21 and 17.77 in malignant tumors. The mean differences between with and without contrast injection for VI, FI and VFI were, respectively, 17.63, 5.07 and 7.45 in benign tumors, and 38.15, 11.88 and 16.55 in malignant tumors. Tumor volume, VI, FI and VFI were not significantly different between benign and malignant tumors before and after echo-contrast medium injection. However, VI, FI and VFI under self-differentiation (differences between with and without contrast injection) were significantly different between malignant and benign tumors. Three-dimensional power Doppler ultrasound is a valuable tool for differential diagnosis of soft-tissue tumors, especially with the injection of an echo-contrast medium. Copyright © 2010 Elsevier. Published by Elsevier B.V. All rights reserved.

Non-destructive testing of layer-to-layer fusion of a 3D print using ultrahigh resolution optical coherence tomography

Science.gov (United States)

Israelsen, Niels M.; Maria, Michael; Feuchter, Thomas; Podoleanu, Adrian; Bang, Ole

2017-06-01

Within the last decade, 3D printing has moved from a costly approach of building mechanical items to the present state-of-the-art phase where access to 3D printers is now common, both in industry and in private places. The plastic printers are the most common type of 3D printers providing prints that are light, robust and of lower cost. The robustness of the structure printed is only maintained if each layer printed is properly fused to its previously printed layers. In situations where the printed component has to accomplish a key mechanical role there is a need to characterize its mechanical strength. This may only be revealed by in-depth testing in order to discover unwanted air-gaps in the structure. Optical coherence tomography (OCT) is an in-depth imaging method, that is sensitive to variations in the refractive index and therefore can resolve with high resolution translucid samples. We report on volume imaging of a 3D printed block made with 100% PLA fill. By employing ultrahigh resolution OCT (UHR-OCT) we show that some parts of the PLA volume reveal highly scattering interfaces which likely correspond to transitions from one layer to another. In doing so, we document that UHR-OCT can act as a powerful tool that can be used in detecting fractures between layers stemming from insufficient fusion between printed structure layers. UHR-OCT can therefore serve as an useful assessment method of quality of 3D prints.

Ultrathin Co3O4 Layers Realizing Optimized CO2 Electroreduction to Formate.

Science.gov (United States)

Gao, Shan; Jiao, Xingchen; Sun, Zhongti; Zhang, Wenhua; Sun, Yongfu; Wang, Chengming; Hu, Qitao; Zu, Xiaolong; Yang, Fan; Yang, Shuyang; Liang, Liang; Wu, Ju; Xie, Yi

2016-01-11

Electroreduction of CO2 into hydrocarbons could contribute to alleviating energy crisis and global warming. However, conventional electrocatalysts usually suffer from low energetic efficiency and poor durability. Herein, atomic layers for transition-metal oxides are proposed to address these problems through offering an ultralarge fraction of active sites, high electronic conductivity, and superior structural stability. As a prototype, 1.72 and 3.51 nm thick Co3O4 layers were synthesized through a fast-heating strategy. The atomic thickness endowed Co3O4 with abundant active sites, ensuring a large CO2 adsorption amount. The increased and more dispersed charge density near Fermi level allowed for enhanced electronic conductivity. The 1.72 nm thick Co3O4 layers showed over 1.5 and 20 times higher electrocatalytic activity than 3.51 nm thick Co3O4 layers and bulk counterpart, respectively. Also, 1.72 nm thick Co3O4 layers showed formate Faradaic efficiency of over 60% in 20 h. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

MPLNET V3 Cloud and Planetary Boundary Layer Detection

Science.gov (United States)

Lewis, Jasper R.; Welton, Ellsworth J.; Campbell, James R.; Haftings, Phillip C.

2016-01-01

The NASA Micropulse Lidar Network Version 3 algorithms for planetary boundary layer and cloud detection are described and differences relative to the previous Version 2 algorithms are highlighted. A year of data from the Goddard Space Flight Center site in Greenbelt, MD consisting of diurnal and seasonal trends is used to demonstrate the results. Both the planetary boundary layer and cloud algorithms show significant improvement of the previous version.

Significant relaxation of residual negative carrier in polar Alq3 film directly detected by high-sensitivity photoemission

Science.gov (United States)

Kinjo, Hiroumi; Lim, Hyunsoo; Sato, Tomoya; Noguchi, Yutaka; Nakayama, Yasuo; Ishii, Hisao

2016-02-01

Tris(8-hydroxyquinoline)aluminum (Alq3) has been widely applied as a good electron-injecting layer (EIL) in organic light-emitting diodes. High-sensitivity photoemission measurement revealed a clear photoemission by visible light, although its ionization energy is 5.7 eV. This unusual photoemission is ascribed to Alq3 anions captured by positive polarization charges. The observed electron detachment energy of the anion was about 1 eV larger than the electron affinity reported by inverse photoemission. This difference suggests that the injected electron in the Alq3 layer is energetically relaxed, leading to the reduction in injection barrier. This nature is one of the reasons why Alq3 worked well as the EIL.

Non-destructive testing of layer-to-layer fusion of a 3D print using ultrahigh resolution optical coherence tomography

DEFF Research Database (Denmark)

Israelsen, Niels Møller; Maria, Michael; Feuchter, Thomas

2017-01-01

Within the last decade, 3D printing has moved from a costly approach of building mechanical items to the present state-of-the-art phase where access to 3D printers is now common, both in industry and in private places. The plastic printers are the most common type of 3D printers providing prints...... on volume imaging of a 3D printed block made with 100% PLA fill. By employing ultrahigh resolution OCT (UHR-OCT) we show that some parts of the PLA volume reveal highly scattering interfaces which likely correspond to transitions from one layer to another. In doing so, we document that UHR-OCT can act...... as a powerful tool that can be used in detecting fractures between layers stemming from insufficient fusion between printed structure layers. UHR-OCT can therefore serve as an useful assessment method of quality of 3D prints....

Few-Layer Nanoplates of Bi 2 Se 3 and Bi 2 Te 3 with Highly Tunable Chemical Potential

KAUST Repository

Kong, Desheng

2010-06-09

A topological insulator (TI) represents an unconventional quantum phase of matter with insulating bulk band gap and metallic surface states. Recent theoretical calculations and photoemission spectroscopy measurements show that group V-VI materials Bi2Se3, Bi2Te3, and Sb2Te3 are TIs with a single Dirac cone on the surface. These materials have anisotropic, layered structures, in which five atomic layers are covalently bonded to form a quintuple layer, and quintuple layers interact weakly through van der Waals interaction to form the crystal. A few quintuple layers of these materials are predicted to exhibit interesting surface properties. Different from our previous nanoribbon study, here we report the synthesis and characterizations of ultrathin Bi2Te3 and Bi2Se3 nanoplates with thickness down to 3 nm (3 quintuple layers), via catalyst-free vapor-solid (VS) growth mechanism. Optical images reveal thickness-dependent color and contrast for nanoplates grown on oxidized silicon (300 nm SiO2/Si). As a new member of TI nanomaterials, ultrathin TI nanoplates have an extremely large surface-to-volume ratio and can be electrically gated more effectively than the bulk form, potentially enhancing surface state effects in transport measurements. Low-temperature transport measurements of a single nanoplate device, with a high-k dielectric top gate, show decrease in carrier concentration by several times and large tuning of chemical potential. © 2010 American Chemical Society.

Efficiency enhancement of perovskite solar cells using structural and morphological improvement of CH3NH3PbI3 absorber layers

Science.gov (United States)

Alidaei, Maryam; Izadifard, Morteza; Ghazi, Mohammad E.; Ahmadi, Vahid

2018-01-01

Perovskite solar cells have been heavily investigated due to their unique properties such as high power conversion efficiency (PCE), low-cost fabrication by solution processes, high diffusion length, large absorption coefficient, and direct and tunable band gap. PCE of perovskite devices is strongly dependent on the absorber layer properties such as morphology, crystallinity, and compactness, which are required to be optimized. In this work, the CH3NH3PbI3 (170-480 nm) absorber layers with various methylammonium iodine (MAI) concentrations (7, 10, 20 and 40 mg ml-1) and perovskite solar cells with the fluorine-doped tin oxide (400 nm)/C-TiO2 (30 nm)/Meso-TiO2 (400 nm)/CH3NH3PbI3 (170-480 nm)/P3HT (30 nm)/Au (100 nm) structure were fabricated. A two-step solution process was used for deposition of the CH3NH3PbI3 absorber layers. The morphology, crystal structure, and optical properties of the perovskite layer grown on glass and also the photovoltaic properties of the fabricated solar cells were studied. The results obtained showed that by controlling the deposition conditions, due to the reduction in charge recombination, PCE enhancement of the perovskite solar cell (up to 11.6%) was accessible.

Prevalence and correlates of neck injection among people who inject drugs in Tijuana, Mexico.

Science.gov (United States)

Rafful, Claudia; Wagner, Karla D; Werb, Dan; González-Zúñiga, Patricia E; Verdugo, Silvia; Rangel, Gudelia; Strathdee, Steffanie A

2015-11-01

Injecting drugs in the neck has been related to adverse health conditions such as jugular vein thrombosis, deep neck infections, aneurysm, haematomas, airway obstruction, vocal cord paralysis and wound botulism, among others. We identified prevalence and correlates of neck injection among people who inject drugs (PWID) in Tijuana, Mexico. Beginning in 2011, PWID aged ≥18 years who injected drugs within the last month were recruited into a prospective cohort. At baseline and semi-annually, PWID completed interviewer-administered surveys soliciting data on drug-injecting practices. Logistic regression was used to identify predictors of injecting in the neck as the most frequent injection site at a single visit. Of 380 PWID, 35.3% injected in the neck at least once in the past 6 months, among whom 71.6% reported it as their most common injection site, the most common injecting site after the arms (47%). Controlling for age, years injecting and injecting frequency, injecting heroin and methamphetamine two or more times per day and having sought injection assistance were associated with injecting in the neck [adjusted odds ratios (AOR): 2.12; 95% confidence intervals (CI): 1.27-3.53 and AOR: 2.65; 95% CI: 1.52-4.53 respectively]. Injecting in the neck was very common among PWID in Tijuana and was associated with polydrug use and seeking injection assistance. Tailoring harm reduction education interventions for individuals who provide injection assistance ('hit doctors') may allow for the dissemination of safe injecting knowledge to reduce injection-related morbidity and mortality. © 2015 Australasian Professional Society on Alcohol and other Drugs.

Single-Layer Halide Perovskite Light-Emitting Diodes with Sub-Band Gap Turn-On Voltage and High Brightness.

Science.gov (United States)

Li, Junqiang; Shan, Xin; Bade, Sri Ganesh R; Geske, Thomas; Jiang, Qinglong; Yang, Xin; Yu, Zhibin

2016-10-03

Charge-carrier injection into an emissive semiconductor thin film can result in electroluminescence and is generally achieved by using a multilayer device structure, which requires an electron-injection layer (EIL) between the cathode and the emissive layer and a hole-injection layer (HIL) between the anode and the emissive layer. The recent advancement of halide perovskite semiconductors opens up a new path to electroluminescent devices with a greatly simplified device structure. We report cesium lead tribromide light-emitting diodes (LEDs) without the aid of an EIL or HIL. These so-called single-layer LEDs have exhibited a sub-band gap turn-on voltage. The devices obtained a brightness of 591 197 cd m -2 at 4.8 V, with an external quantum efficiency of 5.7% and a power efficiency of 14.1 lm W -1 . Such an advancement demonstrates that very high efficiency of electron and hole injection can be obtained in perovskite LEDs even without using an EIL or HIL.

Carrier Injection and Transport in Blue Phosphorescent Organic Light-Emitting Device with Oxadiazole Host

Directory of Open Access Journals (Sweden)

Tien-Lung Chiu

2012-06-01

Full Text Available In this paper, we investigate the carrier injection and transport characteristics in iridium(IIIbis[4,6-(di-fluorophenyl-pyridinato-N,C2']picolinate (FIrpic doped phosphorescent organic light-emitting devices (OLEDs with oxadiazole (OXD as the bipolar host material of the emitting layer (EML. When doping Firpic inside the OXD, the driving voltage of OLEDs greatly decreases because FIrpic dopants facilitate electron injection and electron transport from the electron-transporting layer (ETL into the EML. With increasing dopant concentration, the recombination zone shifts toward the anode side, analyzed with electroluminescence (EL spectra. Besides, EL redshifts were also observed with increasing driving voltage, which means the electron mobility is more sensitive to the electric field than the hole mobility. To further investigate carrier injection and transport characteristics, FIrpic was intentionally undoped at different positions inside the EML. When FIrpic was undoped close to the ETL, driving voltage increased significantly which proves the dopant-assisted-electron-injection characteristic in this OLED. When the undoped layer is near the electron blocking layer, the driving voltage is only slightly increased, but the current efficiency is greatly reduced because the main recombination zone was undoped. However, non-negligible FIrpic emission is still observed which means the recombination zone penetrates inside the EML due to certain hole-transporting characteristics of the OXD.

Production of a rapidly rotating plasma by cross-field injection of gun-produced plasma

International Nuclear Information System (INIS)

Ohzu, Akira; Ikehata, Takashi; Tanabe, Toshio; Mase, Hiroshi

1984-01-01

Cross-field plasma injection with use of a JxB plasma gun is described as a method to produce rapidly rotating plasma in a crossed electric and magnetic field system. The rotational velocity of the plasma is seriously limited by neutrals surrounding the plasma through strong interactions at the boundary layer. The concentration of neutrals can be reduced by the injection of fully or partially ionized plasma into the discharge volume instead of filling the volume with an operating gas. With use of this method, it is observed that the rotational velocity increases by a factor of 2 to 3 when compared with the conventional method of stationary gas-filling. (author)

A bio-ballistic micro-jet for drug injection into animal skin using a Nd:YAG laser

Science.gov (United States)

Yoh, J. J.; Jang, H.; Park, M.; Han, T.; Hah, J.

2016-01-01

Imaging of the abdominal skin of a guinea pig after injecting a fluorescent probe and biotin via the laser-induced ballistic technique revealed the epidermal and dermal layers which were stained well below 60 \\upmu m underneath the outer layer of the skin. An extensive network of cells was evident in the deeper layer of the stained dermis as the distributed fluorescein isothiocyanate dose was administered by repeated injection using a laser-based micro-jet. We performed optically controlled release of the drug by breaching the guinea pig's skin tissue targeting the region 10-400 \\upmu m beneath the outermost layer. Tissue damage was minimized by reducing the injection volume to approximately 100 nl per pulse. This was done using a micro-jet diameter equal to half of that of a conventional 200 \\upmu m syringe needle. Thus, the optimally controlled delivery of liquid drugs using an irradiated laser pulse was shown to be possible.

Two-phase gas bubble-liquid boundary layer flow along vertical and inclined surfaces

International Nuclear Information System (INIS)

Cheung, F.B.; Epstein, M.

1985-01-01

The behavior of a two-phase gas bubble-liquid boundary layer along vertical and inclined porous surfaces with uniform gas injection is investigated experimentally and analytically. Using argon gas and water as the working fluids, a photographical study of the two-phase boundary layer flow has been performed for various angles of inclination ranging from 45 0 to 135 0 and gas injection rates ranging from 0.01 to 0.1 m/s. An integral method has been employed to solve the system of equations governing the two-phase motion. The effects of the gas injection rate and the angle of inclination on the growth of the boundary layer have been determined. The predicted boundary layer thickness is found to be in good agreement with the experimental results. The calculated axial liquid velocity and the void fraction in the two-phase region are also presented along with the observed flow behavior

Interface inductive currents and carrier injection in hybrid perovskite single crystals

Science.gov (United States)

Kovalenko, Alexander; Pospisil, Jan; Krajcovic, Jozef; Weiter, Martin; Guerrero, Antonio; Garcia-Belmonte, Germà

2017-10-01

Interfaces between the absorbing perovskite and transporting layers are gaining attention as the key locus that governs solar cell operation and long term performance. The interplay of ionic and electronic processes, along with the asymmetrical architecture of any solar cell, makes the interpretation of electrical measurements always inconclusive. A strategy to progress in relating electric responses, operating mechanisms, and device architecture relies upon simplifying the probing structure. Macroscopic CH3NH3PbBr3 single crystals with symmetrical contacts are tested by means of long-time current transient and impedance spectroscopy. It is observed that interfaces govern carrier injection to (and extraction from) perovskite layers through an inductive (negative capacitance) mechanism with a response time in the range of ˜ 1 - 100 s under dark conditions and inert atmosphere. Current transient exhibits a slow recovering after the occurrence of an undershoot, signaling a complex carrier dynamics which involves changes in surface state occupancy.

Prevalence of injections and knowledge of safe injections among rural residents in Central China.

Science.gov (United States)

Yan, Y W; Yan, J; Zhang, G P; Gao, Z L; Jian, H X

2007-08-01

Abuse of the injection services, namely unnecessary injections and unsafe injections, exists extensively in developing countries. Unsafe injection practices contribute to the transmission of blood-borne pathogens. The aims of this study were to survey the prevalence of injections and knowledge of injection safety among the rural residents in Jingzhou district, Hubei, China and to provide scientific data for developing a health educational programme. A retrospective cross-sectional study was conducted in 12 villages, which were selected from the Jingzhou district by the random sampling method. 50 rural residents were interviewed per village using a questionnaire. Among the 595 residents studied, 192 had received at least one injection in the past three months, with an injection prevalence of 32.3 percent and an average of 0.93 injections. 90.3 percent of the rural residents knew that unsafe injections could transmit the following blood-borne pathogens: human immunodeficiency virus (74.4 percent), hepatitis B virus (55.8 percent) and hepatitis C virus (22.9 percent). Logistic regression analysis showed that the residents' age, educational level and residential area were important factors in influencing their knowledge about injection safety. The results indicated that the injection prevalence was high among rural residents in the study area, and their knowledge regarding injection safety should be further improved.

Effects of zinc injection from hot functional test at Tomari Unit 3

International Nuclear Information System (INIS)

Hayakawa, Hitoshi; Mino, Yoshitaka; Nakahama, Satoshi; Aizawa, Yamato; Shimizu, Yuichi; Umehara, Ryuji; Kogawa, Noritaka

2012-09-01

At Tomari Nuclear Power Station unit 3 (hereafter Tomari unit 3, PWR, commercial operation from December 2009), the zinc injection for dose-rate reduction was started as early as at the Hot Functional Test (hereafter HFT) stage, for the first time in the world. The results of the Steam Generator (hereafter SG) insert plate analysis and the ambient dose-rate measurement till the end of the test operation reported heretofore, show the formation of the robust oxide film on the primary material surfaces and the associated corrosion suppression effect, and a considerable dose-rate reduction of about 40 to 60% lower than a reference plant. (*: Asian Water Chemistry Symposium in Nagoya on 2009 and NPC2010 in Canada). The material of SG tube is Alloy 690TT in Tomari unit 3. Generally, the dose-rates of the plants with Alloy 690TT SG are the highest at the 1. or 2. refueling outage (hereafter RFO), due to the effects of the Ni dissolution from the initial corrosion of Alloy 690TT. Therefore, the dose-rate of Tomari unit 3 at the 1. RFO is compared with those of the other Japanese PWR plants at their 1. RFO. As the result, the dose-rates inside the main components such as SG, Main Coolant Pipe (hereafter MCP) and Reactor Vessel (hereafter RV) are about 50% lower at the 1. RFO of Tomari unit 3 than those of a reference plant (a 3-Loop PWR plant in Japan). Therefore, an additional dose-rate reduction effects is expected by the Ni release rate reduction from Alloy 690TT and the effect of zinc injection. In this report, the actual dose-rates at the primary main components, the trends of the water chemistry and dose rates reduction effect with the zinc injection at the 1. RFO (offline in January 2011) of Tomari unit 3 are introduced. Also, a part of the experiences at the 2. RFO (offline in May 2012) is introduced. (authors)

MOHOS-type memory performance using HfO2 nanoparticles as charge trapping layer and low temperature annealing

International Nuclear Information System (INIS)

Molina, Joel; Ortega, Rafael; Calleja, Wilfrido; Rosales, Pedro; Zuniga, Carlos; Torres, Alfonso

2012-01-01

Highlights: ► HfO 2 nanoparticles used as charge trapping layer in MOHOS memory devices. ► Increasing HfO 2 nanoparticles concentration enhances charge injection and trapping. ► Enhancement of memory performance with low temperature annealing. ► Charge injection is done without using any hot-carrier injection mechanism. ► Using injected charge density is better for comparison of scaled memory devices. - Abstract: In this work, HfO 2 nanoparticles (np-HfO 2 ) are embedded within a spin-on glass (SOG)-based oxide matrix and used as a charge trapping layer in metal–oxide–high-k–oxide–silicon (MOHOS)-type memory applications. This charge trapping layer is obtained by a simple sol–gel spin coating method after using different concentrations of np-HfO 2 and low temperature annealing (down to 425 °C) in order to obtain charge–retention characteristics with a lower thermal budget. The memory's charge trapping characteristics are quantized by measuring both the flat-band voltage shift of MOHOS capacitors (writing/erasing operations) and their programming retention times after charge injection while correlating all these data to np-HfO 2 concentration and annealing temperature. Since a large memory window has been obtained for our MOHOS memory, the relatively easy injection/annihilation (writing/erasing) of charge injected through the substrate opens the possibility to use this material as an effective charge trapping layer. It is shown that by using lower annealing temperatures for the charge trapping layer, higher densities of injected charge are obtained along with enhanced retention times. In conclusion, by using np-HfO 2 as charge trapping layer in memory devices, moderate programming and retention characteristics have been obtained by this simple and yet low-cost spin-coating method.

Sidewall GaAs tunnel junctions fabricated using molecular layer epitaxy

Directory of Open Access Journals (Sweden)

Takeo Ohno and Yutaka Oyama

2012-01-01

Full Text Available In this article we review the fundamental properties and applications of sidewall GaAs tunnel junctions. Heavily impurity-doped GaAs epitaxial layers were prepared using molecular layer epitaxy (MLE, in which intermittent injections of precursors in ultrahigh vacuum were applied, and sidewall tunnel junctions were fabricated using a combination of device mesa wet etching of the GaAs MLE layer and low-temperature area-selective regrowth. The fabricated tunnel junctions on the GaAs sidewall with normal mesa orientation showed a record peak current density of 35 000 A cm-2. They can potentially be used as terahertz devices such as a tunnel injection transit time effect diode or an ideal static induction transistor.

Magnetism reflectometer study shows LiF layers improve efficiency in spin valve devices

Energy Technology Data Exchange (ETDEWEB)

Bardoel, Agatha A [ORNL; Lauter, Valeria [ORNL; Szulczewski, Greg J [ORNL

2012-01-01

New, more efficient materials for spin valves - a device used in magnetic sensors, random access memories, and hard disk drives - may be on the way based on research using the magnetism reflectometer at Oak Ridge National Laboratory (ORNL). Spin valve devices work by means of two or more conducting magnetic material layers that alternate their electrical resistance depending on the layers alignment. Giant magnetoresistance is a quantum mechanical effect first observed in thin film structures about 20 years ago. The effect is observed as a significant change in electrical resistance, depending on whether the magnetization of adjacent ferromagnetic layers is in a parallel or an antiparallel magnetic alignment. 'What we are doing here is developing new materials. The search for new materials suitable for injecting and transferring carriers with a preferential spin orientation is most important for the development of spintronics,' said Valeria Lauter, lead instrument scientist on the magnetism reflectometer at the Spallation Neutron Source (SNS), who collaborated on the experiment. The researchers discovered that the conductivity of such materials is improved when an organic polymer semiconductor layer is placed between the magnetic materials. Organic semiconductors are now the material of choice for future spin valve devices because they preserve spin coherence over longer times and distances than conventional semiconductors. While research into spin valves has been ongoing, research into organic semiconductors is recent. Previous research has shown that a 'conductivity mismatch' exists in spin valve systems in which ferromagnetic metal electrodes interface with such organic semiconductors as Alq3 ({pi}-conjugated molecule tris(8-hydroxy-quinoline) aluminium). This mismatch limits the efficient injection of the electrons from the electrodes at the interface with the semiconductor material. However, lithium fluoride (LiF), commonly used in light

Radiative edge layers in limiter tokamaks

International Nuclear Information System (INIS)

Monier-Garbet, P.

1997-01-01

The characteristics of the highly radiative edge layers produced in the limiter configuration and with an open ergodic divertor are reviewed, with emphasis on the results obtained in TEXTOR and Tore Supra. In these two experiments an impurity injection technique is used to obtain highly radiating homogeneous peripheral layers. This requires that the peripheral radiation capability be maximized, while at the same time avoiding plasma core contamination; it is also necessary to insure the stability of the radiating layer. These physics issues, governing the success of the highly radiative edge scenario, are discussed. (orig.)

Mitigation of divertor heat flux by high-frequency ELM pacing with non-fuel pellet injection in DIII-D

Directory of Open Access Journals (Sweden)

A. Bortolon

2017-08-01

Full Text Available Experiments have been conducted on DIII-D investigating high repetition rate injection of non-fuel pellets as a tool for pacing Edge Localized Modes (ELMs and mitigating their transient divertor heat loads. Effective ELM pacing was obtained with injection of Li granules in different H-mode scenarios, at frequencies 3–5 times larger than the natural ELM frequency, with subsequent reduction of strike-point heat flux (Bortolon et al., Nucl. Fus., 56, 056008, 2016. However, in scenarios with high pedestal density (∼6 ×1019m−3, the magnitude of granule triggered ELMs shows a broad distribution, in terms of stored energy loss and peak heat flux, challenging the effectiveness of ELM mitigation. Furthermore, transient heat-flux deposition correlated with granule injections was observed far from the strike-points. Field line tracing suggest this phenomenon to be consistent with particle loss into the mid-plane far scrape-off layer, at toroidal location of the granule injection.

Co-Injection Resin Transfer Molding for Optimization of Integral Armor

National Research Council Canada - National Science Library

Fink, B

1998-01-01

... enhancement over existing defense industry practices. CIRTM was invented and developed for single-step manufacturing of integral armor by enabling simultaneous injection of multiple resins into multi-layer preform...

A vertically integrated dynamic RAM-cell: Buried bit line memory cell with floating transfer layer

NARCIS (Netherlands)

Mouthaan, A.J.; Vertregt, Maarten

1986-01-01

A charge injection device has been realized in which charge can be injected on to an MOS-capacitor from a buried layer via an isolated transfer layer. The cell is positioned vertically between word and bit line. LOCOS (local oxidation) is used to isolate the cells and (deep) ion implantation to

System for removing contaminated surface layers

International Nuclear Information System (INIS)

Yoshikawa, Kozo.

1987-04-01

The object of the present invention is to offer a new type of useful decontamination system, with which the contaminated surface layers can be removed effectively by injection of such solid microparticles. Liquid carbon dioxide is passed from a liquid carbon dioxide tank via the carbon dioxide supply line into the system for injecting solid carbon dioxide particles. Part of the liquid carbon dioxide introduced into the system is converted to solid carbon dioxide particles by the temperature drop resulting from adiabatic expansion in the carbon dioxide expansion space of the injection system. The solid carbon dioxide particles reach the injection nozzle, which is connected through the expansion space. The carbon dioxide microparticles are further cooled and accelerated by nitrogen gas injected from the nitrogen gas nozzle at the tip of the nitrogen gas supply line, which is connected to a liquid nitrogen tank. The cooled and accelerated solid carbon dioxide microparticles are injected from the injection nozzle for the solid carbon dioxide and directed against the contaminated surface to be cleaned, and, as a result, the surface contamination is removed

Efficient removal of arsenic by strategically designed and layer-by-layer assembled PS@+rGO@GO@Fe3O4 composites.

Science.gov (United States)

Kang, Bong Kyun; Lim, Byeong Seok; Yoon, Yeojoon; Kwag, Sung Hoon; Park, Won Kyu; Song, Young Hyun; Yang, Woo Seok; Ahn, Yong-Tae; Kang, Joon-Wun; Yoon, Dae Ho

2017-10-01

The PS@+rGO@GO@Fe 3 O 4 (PG-Fe 3 O 4 ) hybrid composites for Arsenic removal were successfully fabricated and well dispersed using layer-by-layer assembly and a hydrothermal method. The PG-Fe 3 O 4 hybrid composites were composed of uniformly coated Fe 3 O 4 nanoparticles on graphene oxide layers with water flow space between 3D structures providing many contact area and adsorption sites for Arsenic adsorption. The PG-Fe 3 O 4 hybrid composite has large surface adsorption sites and exhibits high adsorption capacities of 104 mg/g for As (III) and 68 mg/g for As (V) at 25 °C and pH 7 comparison with pure Fe 3 O 4 and P-Fe 3 O 4 samples. Copyright © 2017 Elsevier Ltd. All rights reserved.

76 FR 36129 - Underground Injection Control Program; Hazardous Waste Injection Restrictions; Petition for...

Science.gov (United States)

2011-06-21

... ENVIRONMENTAL PROTECTION AGENCY [FRL-9321-3] Underground Injection Control Program; Hazardous Waste Injection Restrictions; Petition for Exemption--Class I Hazardous Waste Injection; ExxonMobil... disposal Restrictions, under the 1984 Hazardous and Solid Waste Amendments to the Resource Conservation and...

Determination of the optional time for taking blood samples by single intravenous injection of 3H-leucine

International Nuclear Information System (INIS)

Meng Delian; Yao Junhu; Lu Jinyin; Wu Xiaobin; Liu Jun

2003-01-01

Twenty four young hens (1.5 kg of body weight, BW) were randomly divided into 4 groups. Every group was diet free (FAS) or force-fed a nitrogen-free diet (NFD) or the diet with 20% crude protein in which soybean meal or cotton seed meal was the sole nitrogen source (30 g DM/kg BW). 30 μCi 3 H-Leu/kg BW was intravenously injected into all birds just after force-fed or on fasting. Venous blood samples were taken at 5, 30 min, 4,24,36 and 48h after injection. The excreta during the whole period of 48h after injection was collected. Special radioactivities of nonprotein plasma at every time point and excreta were measured. The optional time of taking blood samples was 20-24 hours after injected 3 H-Leu

76 FR 42125 - Underground Injection Control Program; Hazardous Waste Injection Restrictions; Petition for...

Science.gov (United States)

2011-07-18

... ENVIRONMENTAL PROTECTION AGENCY [FRL-9440-3] Underground Injection Control Program; Hazardous Waste Injection Restrictions; Petition for Exemption--Class I Hazardous Waste Injection; ConocoPhillips... Restrictions, under the 1984 Hazardous and Solid Waste Amendments to the Resource Conservation and Recovery Act...

Improvement of photoluminescence from Ge layer with patterned Si3N4 stressors

International Nuclear Information System (INIS)

Oda, Katsuya; Okumura, Tadashi; Tani, Kazuki; Saito, Shin-ichi; Ido, Tatemi

2014-01-01

Lattice strain applied by patterned Si 3 N 4 stressors in order to improve the optical properties of Ge layers directly grown on a Si substrate was investigated. Patterned Si 3 N 4 stressors were fabricated by various methods and their effects on the strain and photoluminescence were studied. Although we found that when the stressor was fabricated by thermal chemical vapor deposition (CVD), the Ge waveguide was tensilely and compressively strained in the edge and center positions, respectively, and photoluminescence (PL) could be improved by decreasing the width of the waveguide, the crystallinity of the Ge waveguide was degraded by the thermal impact of the deposition process. Low-temperature methods were therefore used to make the patterned stressors. The tensile strain of the Ge layer increased from 0.14% to 0.2% when the stressor was grown by plasma enhanced CVD at 350 °C, but the effects of the increased tensile strain could not be confirmed because the Si 3 N 4 layer was unstable when irradiated with the excitation light used in photoluminescence measurements. Si 3 N 4 stressors grown by inductively coupled plasma CVD at room temperature increased the tensile strain of the Ge layer up to 0.4%, thus red-shifting the PL peak and obviously increasing the PL intensity. These results indicate that the Si 3 N 4 stressors fabricated by the room-temperature process efficiently improve the performance of Ge light-emitting devices. - Highlights: • Ge layers were directly grown on a Si substrate by low-temperature epitaxial growth. • Si 3 N 4 stressors were fabricated on the Ge layers by various methods. • Tensile strain of the Ge layers was improved by the Si 3 N 4 stressors. • Photoluminescence (PL) intensity was increased with the Si 3 N 4 stressors. • Red-shift of the PL spectra was observed from the tensile strained Ge layers

FAFNER - a fully 3-D neutral beam injection code using Monte Carlo methods

International Nuclear Information System (INIS)

Lister, G.G.

1985-01-01

A computer code is described which models the injection of fast neutral particles into 3-dimensional toroidal plasmas and follows the paths of the resulting fast ions until they are either lost to the system or fully thermalised. A comprehensive model for the neutral beam injection system is included. The code is written especially for the use on the CRAY-1 computer: in particular, the modular nature of the program should enable the most time consuming sections of the program to be vectorised for each particular experiment to be modelled. The effects of plasma contamination by possible injection of impurities, such as oxygen, with the beams are also included. The code may also be readily adapted to plasmas for which a 1 or 2-dimensional description is adequate. It has also been constructed with a view to ready coupling with a transport or equilibrium code. (orig.)

Percutaneous injection of intradiscal space with O2-O3 mixture to treat cervical disc herniation

International Nuclear Information System (INIS)

He Xiaofeng; Li Yanhao; Lu Wei; Peng Jing; Chen Yong; Shen Peng; Zeng Qingyue; Zhao Jianbo; Wang Jiangyun; Xu Xiaoli; Chen Hanwei; Xin Yongtong

2005-01-01

Objective: To evaluate the security and therapeutic effect for the treatment of cervical disc herniation with O 2 -O 3 mixture. Methods: Thirty-two patients with cervical herniated discs verified by MRI were selected in study, and all patients presented the symptoms of upper limb, cervical and shoulder areas pain. The procedure was guided by DSA and their puncture route was defined as the right common cervical artery and trachea clearance. 1.5-3.0 ml O 2 -O 3 mixture gas at (30-50) μg/ml was injected into every herniated disc space and 3-5 ml mixture gas was injected in paraspinal space. Results: Thirty-two patients were followed up from 3 to 32 months after treatment. The therapeutic effect showed that 17 cases (53.1%) had excellent recovery, 8 cases (25.0%) had significant relief of symptoms, and 7 cases (21.9%) got failure in treatment. No serious complication occurred. Conclusion: The therapeutic method developed by using O 2 -O 3 mixture injection in cervical intradiscal space was a safe and effective method for the treatment of the cervical disc herniation. (authors)

MOHOS-type memory performance using HfO{sub 2} nanoparticles as charge trapping layer and low temperature annealing

Energy Technology Data Exchange (ETDEWEB)

Molina, Joel, E-mail: jmolina@inaoep.mx [National Institute of Astrophysics, Optics and Electronics. Electronics Department, Luis Enrique Erro 1, Tonantzintla, Puebla 72000 (Mexico); Ortega, Rafael; Calleja, Wilfrido; Rosales, Pedro; Zuniga, Carlos; Torres, Alfonso [National Institute of Astrophysics, Optics and Electronics. Electronics Department, Luis Enrique Erro 1, Tonantzintla, Puebla 72000 (Mexico)

2012-09-20

Highlights: Black-Right-Pointing-Pointer HfO{sub 2} nanoparticles used as charge trapping layer in MOHOS memory devices. Black-Right-Pointing-Pointer Increasing HfO{sub 2} nanoparticles concentration enhances charge injection and trapping. Black-Right-Pointing-Pointer Enhancement of memory performance with low temperature annealing. Black-Right-Pointing-Pointer Charge injection is done without using any hot-carrier injection mechanism. Black-Right-Pointing-Pointer Using injected charge density is better for comparison of scaled memory devices. - Abstract: In this work, HfO{sub 2} nanoparticles (np-HfO{sub 2}) are embedded within a spin-on glass (SOG)-based oxide matrix and used as a charge trapping layer in metal-oxide-high-k-oxide-silicon (MOHOS)-type memory applications. This charge trapping layer is obtained by a simple sol-gel spin coating method after using different concentrations of np-HfO{sub 2} and low temperature annealing (down to 425 Degree-Sign C) in order to obtain charge-retention characteristics with a lower thermal budget. The memory's charge trapping characteristics are quantized by measuring both the flat-band voltage shift of MOHOS capacitors (writing/erasing operations) and their programming retention times after charge injection while correlating all these data to np-HfO{sub 2} concentration and annealing temperature. Since a large memory window has been obtained for our MOHOS memory, the relatively easy injection/annihilation (writing/erasing) of charge injected through the substrate opens the possibility to use this material as an effective charge trapping layer. It is shown that by using lower annealing temperatures for the charge trapping layer, higher densities of injected charge are obtained along with enhanced retention times. In conclusion, by using np-HfO{sub 2} as charge trapping layer in memory devices, moderate programming and retention characteristics have been obtained by this simple and yet low-cost spin-coating method.

Association between continuous peripheral i.v. infusion of 3% sodium chloride injection and phlebitis in adults.

Science.gov (United States)

Meng, Lina; Nguyen, Cherwyn M; Patel, Samit; Mlynash, Michael; Caulfield, Anna Finley

2018-03-01

One institution's experience with use of peripheral i.v. (PIV) catheters for prolonged infusions of 3% sodium chloride injection at rates up to 100 mL/hr is described. A prospective, observational, 13-month quality assurance project was conducted at an academic medical center to evaluate frequencies of patient and catheter phlebitis among adult inpatients who received both an infusion of 3% sodium chloride injection for a period of ≥4 hours through a dedicated PIV catheter and infusions of routine-care solutions (RCSs) through separate PIV catheters during the same hospital stay. Sixty patients received PIV infusions through a total of 291 catheters during the study period. The majority of patients (78%) received infusions of 3% sodium chloride injection for intracranial hypertension, with 30% receiving such infusions in the intensive care unit. Phlebitis occurred in 28 patients (47%) during infusions of 3% sodium chloride and 26 patients (43%) during RCS infusions ( p = 0.19). Catheter phlebitis occurred in 73 catheters (25%), with no significant difference in the frequencies of catheter phlebitis with infusion of 3% sodium chloride versus RCSs (30% [32 of 106 catheters]) versus 22% [41 of 185 catheters]), p = 0.16). Patient and catheter phlebitis rates were not significantly different with infusions of 3% sodium chloride injection versus RCSs, suggesting that an osmolarity cutoff value of 900 mOsm/L for peripheral infusions of hypertonic saline solutions may not be warranted. Copyright © 2018 by the American Society of Health-System Pharmacists, Inc. All rights reserved.

YBCO/manganite layered structures on NdGaO{sub 3} substrates

Energy Technology Data Exchange (ETDEWEB)

Nurgaliev, T [Institute of Electronics BAS, 72 Tsarigradsko Chaussee, 1784 Sofia (Bulgaria); Blagoev, B [Institute of Electronics BAS, 72 Tsarigradsko Chaussee, 1784 Sofia (Bulgaria); Donchev, T [Institute of Electronics BAS, 72 Tsarigradsko Chaussee, 1784 Sofia (Bulgaria); Miteva, S [Institute of Electronics BAS, 72 Tsarigradsko Chaussee, 1784 Sofia (Bulgaria); Mozhaev, P B [Institute of Physics and Technology RAS, Nakhimovsky ave. 36, 117218 Moscow (Russian Federation); Mozhaeva, J E [Institute of Physics and Technology RAS, Nakhimovsky ave. 36, 117218 Moscow (Russian Federation); Ovsyannikov, G A [Institute of Radio Engineering and Electronics RAS, Mokhovaya st.11, 103907 Moscow (Russian Federation); Kotelyanskii, I M [Institute of Radio Engineering and Electronics RAS, Mokhovaya st.11, 103907 Moscow (Russian Federation); Jacobsen, C [Technical University of Denmark, Building 307-309, DK-2800, Kgs.Lyngby, Denmark (Denmark)

2006-06-01

Results of deposition of YBa{sub 2}Cu{sub 3}O{sub 7-x}/CeO{sub 2}/(La{sub 0.7}Ca{sub 0.3}MnO{sub 3} or La{sub 0.7}Sr{sub 0.3}MnO{sub 3}) structures on the standard oriented and tilted ( 8{sup 0}) NdGaO{sub 3} substrates and results of investigation of electrical parameters of YBa{sub 2}Cu{sub 3}O{sub 7-x} (YBCO) films in such structures are presented. The YBCO component of the structure exhibits lower value of the critical parameters in comparison with those of single YBCO films. The contribution of the magnetic layer to the microwave losses of the YBCO film in the layered structure is evaluated.

Modelling and Simulation of Structural Deformation of Isothermal Subsurface Flow and Carbon Dioxide Injection

KAUST Repository

El-Amin, Mohamed; Negara, Ardiansyah; Salama, Amgad; Sun, Shuyu

2011-01-01

force term. The flux continuity condition is used at interfaces between different permeability layers of the heterogeneous medium. We analyze the vertical migration of a CO2 plume injected into a 2D layered reservoir. Analysis of distribution of flow

Electrodeposition of Fe_3O_4 layer from solution of Fe_2(SO_4)_3 with addition ethylene glycol

International Nuclear Information System (INIS)

Dahlan, Dahyunir; Asrar, Allan

2016-01-01

The electrodeposition of Fe_3O_4 layer from the solution Fe_2(SO_4)_3 with the addition of ethylene glycol on Indium Tin Oxide (ITO) substrate has been performed. The electrodeposition was carried out using a voltage of 5 volts for 120 seconds, with and without the addition of 2% wt ethylene glycol. Significant effects of temperature on the resulting the samples is observed when they are heated at 400 °C. Structural characterization using X-ray diffraction (XRD) shows that all samples produce a layer of Fe_3O_4 with particle size less than 50 nanometers. The addition of ethylene glycol and the heating of the sample causes a shrinkage in particle size. The scanning electron microscopy (SEM) characterization shows that Fe_3O_4 layer resulting from the process of electrodeposition of Fe_2(SO_4)_3 without ethylene glycol, independent of whether the sample is heated or not, is uneven and buildup. Layer produced by the addition of ethylene glycol without heating produces spherical particles. On contrary, when the layer is heated the spherical particles transform to irregularly-shaped particles with smaller size.

A Comment Upon Previous Studies on 3-D Boundary Layer Transition

OpenAIRE

ÇARPINLIOĞLU, Melda Özdinç

2014-01-01

The common feature of the experimental studies upon 3-D boundary layer development on swept flat plates cited in the available literature is the application of streamwise and/or spanwise pressure gradients. In fact; presence of the pressure gradients was suggested to be vital for having crossflow effective in 3-D boundary layer transition. In the presented paper here, this idea is questioned evaluating the results of an experimental investigation conducted on swept flat plates under the ab...

Performance enhancement of pentacene-based organic thin-film transistors using 6,13-pentacenequinone as a carrier injection interlayer

Science.gov (United States)

Fan, Ching-Lin; Lin, Wei-Chun; Chen, Hao-Wei

2018-06-01

This work demonstrates pentacene-based organic thin-film transistors (OTFTs) fabricated by inserting a 6,13-pentacenequinone (PQ) carrier injection layer between the source/drain (S/D) metal Au electrodes and pentacene channel layer. Compared to devices without a PQ layer, the performance characteristics including field-effect mobility, threshold voltage, and On/Off current ratio were significantly improved for the device with a 5-nm-thick PQ interlayer. These improvements are attributed to significant reduction of hole barrier height at the Au/pentacene channel interfaces. Therefore, it is believed that using PQ as the carrier injection layer is a good candidate to improve the pentacene-based OTFTs electrical performance.

Boundary layer plasmas as a source for high-latitude, early afternoon, auroral arcs

International Nuclear Information System (INIS)

Lundin, R.; Evans, D.S.

1985-02-01

Simultaneous measurements of hot boundary layer plasma from PROGNOZ-7 and particle precipitation from the TIROS/NOAA satellite in nearly magnetically conjugate regions have been used to study the dynamo process responsible for the formation of high latitude, early afternoon, auroral arcs. Characteristic for the PROGNOZ-7 observations in the dayside boundary layer at high latitudes is the frequent occurrence of regions with injected magnetosheath plasma embedded in a 'halo' of antisunward flowing magnetosphere plasma. The injected magnetosheath plasma have several features which indicate that it also acts as a local source of EMF in the boundary layer. The process resembles that of a local MHD dynamo driven by the excess drift velocity of the injected magnetosheath plasma relative to the background magnetospheric plasma. The dynamo region is capable of driving fielc-aligned currents that couple to the ionosphere, where the upward current is associated with the high latitude auroral arcs. We demonstrate that the large-scale morphology as well as the detailed data intercomparison between PROGNOZ-7 and TIROS-N both agree well with a local injection of magnetosheath plasma into the dayside boundary layer as the main dynamo process powering the high-latitude, early afternoon auroral arcs. (Author)

Cross-flow analysis of injection wells in a multilayered reservoir

Directory of Open Access Journals (Sweden)

Mohammadreza Jalali

2016-09-01

Natural and forced cross-flow is modeled for some injection wells in an oil reservoir located at North Sea. The solution uses a transient implicit finite difference approach for multiple sand layers with different permeabilities separated by impermeable shale layers. Natural and forced cross-flow rates for each reservoir layer during shut-in are calculated and compared with different production logging tool (PLT measurements. It appears that forced cross-flow is usually more prolonged and subject to a higher flow rate when compared with natural cross-flow, and is thus worthy of more detailed analysis.

Improved hole-injection and power efficiency of organic light-emitting diodes using an ultrathin cerium fluoride buffer layer

Science.gov (United States)

Lu, Hsin-Wei; Kao, Po-Ching; Chu, Sheng-Yuan

2016-09-01

In this study, the efficiency of organic light-emitting diodes (OLEDs) was enhanced by depositing a CeF3 film as an ultra-thin buffer layer between the ITO and NPB hole transport layer, with the structure configuration ITO/CeF3 (1 nm)/NPB (40 nm)/Alq3 (60 nm)/LiF (1 nm)/Al (150 nm). The enhancement mechanism was systematically investigated via several approaches. The work function increased from 4.8 eV (standard ITO electrode) to 5.2 eV (1-nm-thick UV-ozone treated CeF3 film deposited on the ITO electrode). The turn-on voltage decreased from 4.2 V to 4.0 V at 1 mA/cm2, the luminance increased from 7588 cd/m2 to 10820 cd/m2, and the current efficiency increased from 3.2 cd/A to 3.5 cd/A when the 1-nm-thick UV-ozone treated CeF3 film was inserted into the OLEDs.

Enhanced spin accumulation in Fe3O4 based spin injection devices below the Verwey transition

Science.gov (United States)

Bhat, Shwetha G.; Kumar, P. S. Anil

2016-12-01

Spin injection into GaAs and Si (both n and p-type) semiconductors using Fe3O4 is achieved with and without a tunnel barrier (MgO) via three-terminal electrical Hanle measurement. Interestingly, the magnitude of spin accumulation voltage (ΔV) in semiconductor is found to be associated with a drastic increment in ΔV in Fe3O4 based devices for temperature metal-to-insulator transition of Fe3O4 at T V. Observations from our elaborate investigations show that spin polarization of Fe3O4 has an explicit influence on the enhanced spin injection. It is argued that the theoretical prediction of half-metallicity of Fe3O4 above and below T V has to be reinvestigated.

The enhanced electron injection by fluorinated tris-(8-hydroxy-quinolinato) aluminum derivatives in high efficient Si-anode OLEDs

Energy Technology Data Exchange (ETDEWEB)

Liu, N. [State Key Laboratory of Silicon Materials, MOE Key Laboratory of Macromolecule Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027 (China); Shi, M.M., E-mail: minminshi@zju.edu.c [State Key Laboratory of Silicon Materials, MOE Key Laboratory of Macromolecule Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027 (China); Li, Y.Z. [School of Physics, State Key Laboratory for Mesoscopic Physics, Peking University, Beijing 100871 (China); Shi, Y.W. [State Key Laboratory of Silicon Materials, MOE Key Laboratory of Macromolecule Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027 (China); Ran, G.Z.; Qin, G.G. [School of Physics, State Key Laboratory for Mesoscopic Physics, Peking University, Beijing 100871 (China); Wang, M.; Chen, H.Z. [State Key Laboratory of Silicon Materials, MOE Key Laboratory of Macromolecule Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027 (China)

2011-02-15

Fabrication of organic light-emitting diodes (OLEDs) and lasers on silicon substrates is a feasible route to integrate microelectronic chips with optical devices for telecommunications. However, the efficiency of Si-anode based OLEDs is restricted by the imbalance of hole-electron injection because a p-type Si anode owns better hole injection ability than ITO. We have used fluorinated tris-(8-hydroxy-quinolinato) aluminum (FAlq{sub 3}) derivatives to prepare Si-anode based OLEDs. We observed that, when tris-(5-fuloro-8-hydroxyquinolinato) aluminum (5FAlq{sub 3}) is used as the electron-transporting material instead of Alq{sub 3}, the cathode electron injection is enhanced due to its lower lowest unoccupied molecular orbital (LUMO) compared to the Alq{sub 3}. The device can keep the relative carrier balance even when a Si anode capable of stronger hole injection was used. Further optimization of the device structure by introducing 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP) as a hole blocking layer showed significant increase in the device power efficiency from 0.029 to 0.462 lm/W. This indicates that use of fluorinated Alq{sub 3} derivatives is an effective way to improve the performance of Si-anode based OLEDs.

Effects of injection nozzle exit width on rotating detonation engine

Science.gov (United States)

Sun, Jian; Zhou, Jin; Liu, Shijie; Lin, Zhiyong; Cai, Jianhua

2017-11-01

A series of numerical simulations of RDE modeling real injection nozzles with different exit widths are performed in this paper. The effects of nozzle exit width on chamber inlet state, plenum flowfield and detonation propagation are analyzed. The results are compared with that using an ideal injection model. Although the ideal injection model is a good approximation method to model RDE inlet, the two-dimensional effects of real nozzles are ignored in the ideal injection model so that some complicated phenomena such as the reflected waves caused by the nozzle walls and the reversed flow into the nozzles can not be modeled accurately. Additionally, the ideal injection model overpredicts the block ratio. In all the cases that stabilize at one-wave mode, the block ratio increases as the nozzle exit width gets smaller. The dual-wave mode case also has a relatively high block ratio. A pressure oscillation in the plenum with the same main frequency with the rotating detonation wave is observed. A parameter σ is applied to describe the non-uniformity in the plenum. σ increases as the nozzle exit width gets larger. Under some condition, the heat release on the interface of fresh premixed gas layer and detonation products can be strong enough to induce a new detonation wave. A spontaneous mode-transition process is observed for the smallest exit width case. Due to the detonation products existing in the premixed gas layer before the detonation wave, the detonation wave will propagate through reactants and products alternately, and therefore its strength will vary with time, especially near the chamber inlet. This tendency gets weaker as the injection nozzle exit width increases.

[Studies on a sequential injection renewable surface reflectance spectrophotometric system using a microchip flow cell].

Science.gov (United States)

Wang, Jian-ya; Fang, Zhao-lun

2002-02-01

A microchip flow cell was developed for flow injection renewable surface assay by reflectance spectrophotometry. The flow cell was coupled to a sequential injection system and optical fiber photometric detection system. The flow cell featured a three-layer structure. The flow channel was cut into a silicone rubber membrance which formed the middle layer, and a porous filter was inlayed across a widened section of the channel to trap microbeads introduced into the flow cell. The area of the detection window of the flow cell was approximately 3.6 mm2, the volume of the bead trapped in the flow cell was 2.2 microL, the depth of the bead layer was 600 microns. A multistrand bifurcated optical fiber was coupled with incident light, detector and flow cell. The chromogenic reaction of Cr(VI) with 1,5-diphenylcarbohydrazide (DPC) which was adsorbed on trapped Polysorb C-18 beads was used as a model reaction to optimize the flow cell design and the experimental system. The reflectance of the renewable reaction surface was monitored at 540 nm. With 100 microL sample loaded and 1.0 mL.min-1 carrier flow rate, the linear response range was 0-0.6 microgram.mL-1 Cr(VI). A detection limit (3 sigma) of 6 ng.mL-1, precision of 1.5% RSD(n = 11), and a throughput of 64 samples per hour were achieved. Considerations in system and flow cell design, the influence of depth of the bead layer, weight of beads used, and the flow rates of carrier stream on the performance were discussed.

Re-injection feasibility study of fracturing flow-back fluid in shale gas mining

Science.gov (United States)

Kang, Dingyu; Xue, Chen; Chen, Xinjian; Du, Jiajia; Shi, Shengwei; Qu, Chengtun; Yu, Tao

2018-02-01

Fracturing flow-back fluid in shale gas mining is usually treated by re-injecting into formation. After treatment, the fracturing flow-back fluid is injected back into the formation. In order to ensure that it will not cause too much damage to the bottom layer, feasibility evaluations of re-injection of two kinds of fracturing fluid with different salinity were researched. The experimental research of the compatibility of mixed water samples based on the static simulation method was conducted. Through the analysis of ion concentration, the amount of scale buildup and clay swelling rate, the feasibility of re-injection of different fracturing fluid were studied. The result shows that the swelling of the clay expansion rate of treated fracturing fluid is lower than the mixed water of treated fracturing fluid and the distilled water, indicating that in terms of clay expansion rate, the treated fracturing flow-back fluid is better than that of water injection after re-injection. In the compatibility test, the maximum amount of fouling in the Yangzhou oilfield is 12mg/L, and the maximum value of calcium loss rate is 1.47%, indicating that the compatibility is good. For the fracturing fluid with high salinity in the Yanchang oilfield, the maximum amount of scaling is 72mg/L, and the maximum calcium loss rate is 3.50%, indicating that the compatibility is better.

Efficiency Enhancement of Nanotextured Black Silicon Solar Cells Using Al2O3/TiO2 Dual-Layer Passivation Stack Prepared by Atomic Layer Deposition.

Science.gov (United States)

Wang, Wei-Cheng; Tsai, Meng-Chen; Yang, Jason; Hsu, Chuck; Chen, Miin-Jang

2015-05-20

In this study, efficient nanotextured black silicon (NBSi) solar cells composed of silicon nanowire arrays and an Al2O3/TiO2 dual-layer passivation stack on the n(+) emitter were fabricated. The highly conformal Al2O3 and TiO2 surface passivation layers were deposited on the high-aspect-ratio surface of the NBSi wafers using atomic layer deposition. Instead of the single Al2O3 passivation layer with a negative oxide charge density, the Al2O3/TiO2 dual-layer passivation stack treated with forming gas annealing provides a high positive oxide charge density and a low interfacial state density, which are essential for the effective field-effect and chemical passivation of the n(+) emitter. In addition, the Al2O3/TiO2 dual-layer passivation stack suppresses the total reflectance over a broad range of wavelengths (400-1000 nm). Therefore, with the Al2O3/TiO2 dual-layer passivation stack, the short-circuit current density and efficiency of the NBSi solar cell were increased by 11% and 20%, respectively. In conclusion, a high efficiency of 18.5% was achieved with the NBSi solar cells by using the n(+)-emitter/p-base structure passivated with the Al2O3/TiO2 stack.

Self-assembly surface modified indium-tin oxide anodes for single-layer light-emitting diodes

CERN Document Server

Morgado, J; Charas, A; Matos, M; Alcacer, L; Cacialli, F

2003-01-01

We study the effect of indium-tin oxide surface modification by self assembling of highly polar molecules on the performance of single-layer light-emitting diodes (LEDs) fabricated with polyfluorene blends and aluminium cathodes. We find that the efficiency and light-output of such LEDs is comparable to, and sometimes better than, the values obtained for LEDs incorporating a hole injection layer of poly(3,4-ethylene dioxythiophene) doped with polystyrene sulphonic acid. This effect is attributed to the dipole-induced work function modification of indium-tin oxide.

Self-assembly surface modified indium-tin oxide anodes for single-layer light-emitting diodes

International Nuclear Information System (INIS)

Morgado, Jorge; Barbagallo, Nunzio; Charas, Ana; Matos, Manuel; Alcacer, Luis; Cacialli, Franco

2003-01-01

We study the effect of indium-tin oxide surface modification by self assembling of highly polar molecules on the performance of single-layer light-emitting diodes (LEDs) fabricated with polyfluorene blends and aluminium cathodes. We find that the efficiency and light-output of such LEDs is comparable to, and sometimes better than, the values obtained for LEDs incorporating a hole injection layer of poly(3,4-ethylene dioxythiophene) doped with polystyrene sulphonic acid. This effect is attributed to the dipole-induced work function modification of indium-tin oxide

Using self-similarity compensation for improving inter-layer prediction in scalable 3D holoscopic video coding

Science.gov (United States)

Conti, Caroline; Nunes, Paulo; Ducla Soares, Luís.

2013-09-01

Holoscopic imaging, also known as integral imaging, has been recently attracting the attention of the research community, as a promising glassless 3D technology due to its ability to create a more realistic depth illusion than the current stereoscopic or multiview solutions. However, in order to gradually introduce this technology into the consumer market and to efficiently deliver 3D holoscopic content to end-users, backward compatibility with legacy displays is essential. Consequently, to enable 3D holoscopic content to be delivered and presented on legacy displays, a display scalable 3D holoscopic coding approach is required. Hence, this paper presents a display scalable architecture for 3D holoscopic video coding with a three-layer approach, where each layer represents a different level of display scalability: Layer 0 - a single 2D view; Layer 1 - 3D stereo or multiview; and Layer 2 - the full 3D holoscopic content. In this context, a prediction method is proposed, which combines inter-layer prediction, aiming to exploit the existing redundancy between the multiview and the 3D holoscopic layers, with self-similarity compensated prediction (previously proposed by the authors for non-scalable 3D holoscopic video coding), aiming to exploit the spatial redundancy inherent to the 3D holoscopic enhancement layer. Experimental results show that the proposed combined prediction can improve significantly the rate-distortion performance of scalable 3D holoscopic video coding with respect to the authors' previously proposed solutions, where only inter-layer or only self-similarity prediction is used.

Effects of local high-frequency perturbation on a turbulent boundary layer by synthetic jet injection

International Nuclear Information System (INIS)

Guo, Hao; Huang, Qian-Min; Liu, Pei-qing; Qu, Qiu-Lin

2015-01-01

An experimental study is performed to investigate the local high-frequency perturbation effects of a synthetic jet injection on a flat-plate turbulent boundary layer. Parameters of the synthetic jet are designed to force a high-frequency perturbation from a thin spanwise slot in the wall. In the test locations downstream of the slot, it is found that skin-friction is reduced by the perturbation, which is languishingly evolved downstream of the slot with corresponding influence on the near-wall regeneration mechanism of turbulent structures. The downstream slot region is divided into two regions due to the influence strength of the movement of spanwise vortices generated by the high-frequency perturbation. Interestingly, the variable interval time average technique is found to be disturbed by the existence of the spanwise vortices’ motion, especially in the region close to the slot. Similar results are obtained from the analysis of the probability density functions of the velocity fluctuation time derivatives, which is another indirect technique for detecting the enhancement or attenuation of streamwise vortices. However, both methods have shown consistent results with the skin-friction reduction mechanism in the far-away slot region. The main purpose of this paper is to remind researchers to be aware of the probable influence of spanwise vortices’ motion in wall-bounded turbulence control. (paper)

Interfacial charge-induced polarization switching in Al{sub 2}O{sub 3}/Pb(Zr,Ti)O{sub 3} bi-layer

Energy Technology Data Exchange (ETDEWEB)

Kim, Yu Jin; Park, Min Hyuk; Jeon, Woojin; Kim, Han Joon; Moon, Taehwan; Lee, Young Hwan; Kim, Keum Do; Hyun, Seung Dam; Hwang, Cheol Seong, E-mail: cheolsh@snu.ac.kr [Department of Materials Science & Engineering and Inter-University Semiconductor Research Center, College of Engineering, Seoul National University, Seoul 151-744 (Korea, Republic of)

2015-12-14

Detailed polarization switching behavior of an Al{sub 2}O{sub 3}/Pb(Zr,Ti)O{sub 3} (AO/PZT) structure is examined by comparing the phenomenological thermodynamic model to the experimental polarization–voltage (P-V) results. Amorphous AO films with various thicknesses (2–10 nm) were deposited on the polycrystalline 150-nm-thick PZT film. The thermodynamic calculation showed that the transition from the ferroelectric-like state to the paraelectric-like state with increasing AO thickness occurs at ∼3 nm thickness. This paraelectric-like state should have exhibited a negative capacitance effect without permanent polarization switching if no other adverse effects are involved. However, experiments showed typical ferroelectric-like hysteresis loops where the coercive voltage increased with the increasing AO thickness, which could be explained by the carrier injection through the thin AO layer and trapping of the carriers at the AO/PZT interface. The fitting of the experimental P-V loops using the thermodynamic model considering the depolarization energy effect showed that trapped charge density was ∼±0.1 Cm{sup −2} and critical electric field at the Pt electrode/AO interface, at which the carrier transport occurs, was ∼±10 MV/cm irrespective of the AO thickness. Energy band model at each electrostatic state along the P-V loop was provided to elucidate correlation between macroscopic polarization and internal charge state of the stacked films.

Syringe injectable electronics

Science.gov (United States)

Hong, Guosong; Zhou, Tao; Jin, Lihua; Duvvuri, Madhavi; Jiang, Zhe; Kruskal, Peter; Xie, Chong; Suo, Zhigang; Fang, Ying; Lieber, Charles M.

2015-01-01

Seamless and minimally-invasive three-dimensional (3D) interpenetration of electronics within artificial or natural structures could allow for continuous monitoring and manipulation of their properties. Flexible electronics provide a means for conforming electronics to non-planar surfaces, yet targeted delivery of flexible electronics to internal regions remains difficult. Here, we overcome this challenge by demonstrating syringe injection and subsequent unfolding of submicrometer-thick, centimeter-scale macroporous mesh electronics through needles with a diameter as small as 100 micrometers. Our results show that electronic components can be injected into man-made and biological cavities, as well as dense gels and tissue, with > 90% device yield. We demonstrate several applications of syringe injectable electronics as a general approach for interpenetrating flexible electronics with 3D structures, including (i) monitoring of internal mechanical strains in polymer cavities, (ii) tight integration and low chronic immunoreactivity with several distinct regions of the brain, and (iii) in vivo multiplexed neural recording. Moreover, syringe injection enables delivery of flexible electronics through a rigid shell, delivery of large volume flexible electronics that can fill internal cavities and co-injection of electronics with other materials into host structures, opening up unique applications for flexible electronics. PMID:26053995

Fatigue in artificially layered Pb(Zr,Ti)O3 ferroelectric films

Science.gov (United States)

Jiang, A. Q.; Scott, J. F.; Dawber, M.; Wang, C.

2002-12-01

We have performed fatigue tests on lead zirconate titanate (PZT) multilayers having stacks of Pb(Zr0.8Ti0.2)O3/Pb(Zr0.2Ti0.8)O3 with repeated distances of 12 formula groups. The results are compared with single-layer n-type (0.5 at. % Ta-doped) PZT films. We conclude that fatigue is dominated by space-charge layers in each case, but that in the multilayer such space charge accumulates at the layer interfaces, rather than at the electrode-dielectric interface. The model, which includes both drift and diffusion, is quantitative and yields a rate-limiting mobility of 6.9±0.9×10-12 cm2/V s, in excellent agreement with the oxygen vacancy mobility for perovskite oxides obtained from Zafar et al.

Ultrathin Epitaxial Ferromagneticγ-Fe2O3Layer as High Efficiency Spin Filtering Materials for Spintronics Device Based on Semiconductors

KAUST Repository

Li, Peng

2016-06-01

In spintronics, identifying an effective technique for generating spin-polarized current has fundamental importance. The spin-filtering effect across a ferromagnetic insulating layer originates from unequal tunneling barrier heights for spin-up and spin-down electrons, which has shown great promise for use in different ferromagnetic materials. However, the low spin-filtering efficiency in some materials can be ascribed partially to the difficulty in fabricating high-quality thin film with high Curie temperature and/or partially to the improper model used to extract the spin-filtering efficiency. In this work, a new technique is successfully developed to fabricate high quality, ferrimagnetic insulating γ-Fe2O3 films as spin filter. To extract the spin-filtering effect of γ-Fe2O3 films more accurately, a new model is proposed based on Fowler–Nordheim tunneling and Zeeman effect to obtain the spin polarization of the tunneling currents. Spin polarization of the tunneled current can be as high as −94.3% at 2 K in γ-Fe2O3 layer with 6.5 nm thick, and the spin polarization decays monotonically with temperature. Although the spin-filter effect is not very high at room temperature, this work demonstrates that spinel ferrites are very promising materials for spin injection into semiconductors at low temperature, which is important for development of novel spintronics devices. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

The effect of blood injection for the prevention of Ethanol reflux after intrahepatic Ethanol injection in the rat

International Nuclear Information System (INIS)

Ahn, Kook Jin; Kim, Choon Yul; Kim, Bum Soo; Hahn, Seong Tai; Lee, Jae Mun; Shinn, Kyung Sub

1998-01-01

To reduce ethanol reflux from the needle channel by injecting rat blood immediately after the injection of ethanol into rat liver. The first experiment involved 33 rat livers which were divided into four groups (three livers in group 1;ten in groups 2, 3, and 4). Group 1 animals were used as controls, and 0.1ml saline was injected into the liver; in group 2, ethanol-Tc-99m-O 4 - mixed solution (0.1ml, 0.2mCi) was injected into the liver;in groups 3 and 4, the needle channel was blocked with 0.02ml of fresh blood and old blood, respectively, after the injection of ethanol. After removing the needle, a 3cm round filter paper was laid on each injection site to absorb refluxed ethanol-T c -99m-O 4 - mixed solution from the liver, and each paper was then counted by a gamma camera unit. In the second experiment, 33rats were divided into four groups (three rats in group 1;ten in groups 2, 3, and 4). Group 1 animals were used as controls, and after exposing the left lateral lobe of the liver, 0.05 ml of saline was injected;in group 2, 0.05 ml of ethanol was injected into the livder;in groups 3 and 4 the needle channel was blocked with 0.02 ml of fresh blood and old blood, respectively, after the injection of ethanol. After ten days, peritoneal adhesions were scored macroscopically and microscopically. In the first experiment using ethanol- T c -99m-O 4 - mixed solution, groups blocked with blood after the injection of mixed solution showed lower gamma counts than the group injected with mixed solution only (p-value=3D0.0002). The group blocked with old blood showed the lowest count. Macroscopical and microscopical examination of peritoneal adhesions indicated that the grade of adhesion was lower in groups blocked with blood than in the group injected with ethanol onluy (p-value=3D0.0261 and 0.0163, respectively). The above results suggest that an injection of blood after an injection of ethanol is a very effective way of preventing reflux from the liver.=20

Sonographically guided deep plantar fascia injections: where does the injectate go?

Science.gov (United States)

Maida, Eugene; Presley, James C; Murthy, Naveen; Pawlina, Wojciech; Smith, Jay

2013-08-01

To determine the distribution of sonographically guided deep plantar fascia injections in an unembalmed cadaveric model. A single experienced operator completed 10 sonographically guided deep plantar fascia injections in 10 unembalmed cadaveric specimens (5 right and 5 left) obtained from 6 donors (2 male and 4 female) aged 49 to 95 years (mean, 77.5 years) with a mean body mass index of 23.2 kg/m(2) (range, 18.4-26.3 kg/m(2)). A 12-3-MHz linear array transducer was used to direct a 22-gauge, 38-mm stainless steel needle deep to the plantar fascia at the anterior aspect of the calcaneus using an in-plane, medial-to-lateral approach. In each case, 1.5 mL of 50% diluted colored latex was injected deep to the plantar fascia. After a minimum of 72 hours, study coinvestigators dissected each specimen to assess injectate placement. All 10 injections accurately placed latex adjacent to the deep side of the plantar fascia at the anterior calcaneus. However, the flexor digitorum brevis (FDB) origin from the plantar fascia variably limited direct latex contact with the plantar fascia, and small amounts of latex interdigitated with the FDB origin in 90% (9 of 10). In all 10 specimens, latex also covered the traversing first branch of the lateral plantar nerve (FBLPN, ie, Baxter nerve) between the FDB and quadratus plantae muscles. No latex was found in the plantar fat pad or plantar fascia in any specimen. Sonographically guided deep plantar fascia injections reliably deliver latex deep to the plantar fascia while avoiding intrafascial injection. However, the extent of direct plantar fascia contact is variable due to the intervening FDB. On the contrary, the traversing FBLPN is reliably covered by the injection. Deep plantar fascia injections may have a role in the management of refractory plantar fasciitis, particularly following failed superficial perifascial or intrafascial injections, in cases of preferential deep plantar fascia involvement, or when entrapment

The fourth space surgery: endoscopic subserosal dissection for upper gastrointestinal subepithelial tumors originating from the muscularis propria layer.

Science.gov (United States)

Liu, Fei; Zhang, Song; Ren, Wei; Yang, Tian; Lv, Ying; Ling, Tingsheng; Zou, Xiaoping; Wang, Lei

2018-05-01

We developed a novel method of endoscopic subserosal dissection (ESSD) for removal of subepithelial tumors (SETs) originating from the muscularis propria (MP) layer in the upper gastrointestinal (GI) tract. The aim of this study was to evaluate the efficacy, safety, and clinical outcome of this method. Eleven patients with upper GI SETs originating from the MP layer were treated by ESSD between October 2016 and March 2017. ESSD technique consists of six major procedures: (1) incising the mucosal and submucosal layer around the lesion and exposing MP layer; (2) continuous injection was performed while the injection needle slowly moved from the MP layer toward the subserosal layer; (3) incising MP layer; (4) subserosal injection was performed to further separate the serosa from the MP layer; (5) the mucosa, submucosa, and MP layer including SET were carefully dissected en bloc; and (6) closure of the gastric-wall defect with endoscopic techniques. Primary outcome including clinical procedural success and procedure-related adverse events were documented. ESSD was successfully performed in 11 patients. The complete resection rate was 100%, and the mean operation time was 51 (range 22-76) min. The mean resected lesion size was 27 (range 15-40) mm. Pathological diagnosis of these lesions included gastrointestinal stromal tumors (8/11), heterotopic pancreas (1/11), hamartoma (1/11), and leiomyoma (1/11). The small perforations occurred in two patients (4 × 4 and 5 × 5 mm, respectively) during the operation. All perforations and defects were closed successfully by endoscopic techniques. No GI bleeding, peritonitis, abdominal abscess, and other adverse events were observed. No lesion residual or recurrence was found during the follow-up period (mean 18 weeks; range 10-29 weeks). ESSD seems to be an efficacious, safe, and minimally invasive treatment for patients with upper GI SETs originating from the MP layer, making it possible to resect deep lesions, provide

Y2O3:Yb/Er nanotubes: Layer-by-layer assembly on carbon-nanotube templates and their upconversion luminescence properties

International Nuclear Information System (INIS)

Huang, Weishi; Shen, Jianfeng; Wan, Lei; Chang, Yu; Ye, Mingxin

2012-01-01

Graphical abstract: Well-shaped Y 2 O 3 :Yb/Er nanotubes have been successfully synthesized on a large scale via layer-by-layer assembly on carbon nanotubes templates followed by a subsequent heat treatment process. The as-prepared Y 2 O 3 :Yb/Er nanotubes show a strong red emission corresponding to the 4 F 9/2 – 4 I 15/2 transition of the Er 3+ ions under excitation at 980 nm. Display Omitted Highlights: ► Well-shaped Y 2 O 3 :Yb/Er nanotubes have been successfully synthesized. ► CNTs were used as templates for Y 2 O 3 :Yb/Er nanotubes. ► LBL assembly and calcination were used for preparation of Y 2 O 3 :Yb/Er nanotubes. ► The as-prepared Y 2 O 3 :Yb/Er nanotubes show a strong red emission. -- Abstract: Well-shaped Y 2 O 3 :Yb/Er nanotubes have been successfully synthesized on a large scale via layer-by-layer (LBL) assembly on carbon nanotubes (CNTs) templates followed by a subsequent heat treatment process. The crystal structure, element analysis, morphology and upconversion luminescence properties were characterized. XRD results demonstrate that the diffraction peaks of the samples calcinated at 800 °C or above can be indexed to the pure cubic phase of Y 2 O 3 . SEM images indicate that a large quantity of uniform and rough nanotubes with diameters of about 30–60 nm can be observed. The as-prepared Y 2 O 3 :Yb/Er nanotubes show a strong red emission corresponding to the 4 F 9/2 – 4 I 15/2 transition of the Er 3+ ions under excitation at 980 nm, which have potential applications in such fields as nanoscale devices, molecular catalysts, nanobiotechnology, photonics and optoelectronics.

Effect of reservoir heterogeneity on air injection performance in a light oil reservoir

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Hu Jia

2018-03-01

Full Text Available Air injection is a good option to development light oil reservoir. As well-known that, reservoir heterogeneity has great effect for various EOR processes. This also applies to air injection. However, oil recovery mechanisms and physical processes for air injection in heterogeneous reservoir with dip angle are still not well understood. The reported setting of reservoir heterogeneous for physical model or simulation model of air injection only simply uses different-layer permeability of porous media. In practice, reservoir heterogeneity follows the principle of geostatistics. How much of contrast in permeability actually challenges the air injection in light oil reservoir? This should be investigated by using layered porous medial settings of the classical Dykstra-Parsons style. Unfortunately, there has been no work addressing this issue for air injection in light oil reservoir. In this paper, Reservoir heterogeneity is quantified based on the use of different reservoir permeability distribution according to classical Dykstra-Parsons coefficients method. The aim of this work is to investigate the effect of reservoir heterogeneity on physical process and production performance of air injection in light oil reservoir through numerical reservoir simulation approach. The basic model is calibrated based on previous study. Total eleven pseudo compounders are included in this model and ten complexity of reactions are proposed to achieve the reaction scheme. Results show that oil recovery factor is decreased with the increasing of reservoir heterogeneity both for air and N2 injection from updip location, which is against the working behavior of air injection from updip location. Reservoir heterogeneity sometimes can act as positive effect to improve sweep efficiency as well as enhance production performance for air injection. High O2 content air injection can benefit oil recovery factor, also lead to early O2 breakthrough in heterogeneous reservoir. Well

Efficient charge injection in p-type polymer field-effect transistors with low-cost molybdenum electrodes through V2O5 interlayer.

Science.gov (United States)

Baeg, Kang-Jun; Bae, Gwang-Tae; Noh, Yong-Young

2013-06-26

Here we report high-performance polymer OFETs with a low-cost Mo source/drain electrode by efficient charge injection through the formation of a thermally deposited V2O5 thin film interlayer. A thermally deposited V2O5 interlayer is formed between a regioregular poly(3-hexylthiophene) (rr-P3HT) or a p-type polymer semiconductor containing dodecyl-substituted thienylenevinylene (TV) and dodecylthiophene (PC12TV12T) and the Mo source/drain electrode. The P3HT or PC12TV12T OFETs with the bare Mo electrode exhibited lower charge carrier mobility than those with Au owing to a large barrier height for hole injection (0.5-1.0 eV). By forming the V2O5 layer, the P3HT or PC12TV12T OFETs with V2O5 on the Mo electrode exhibited charge carrier mobility comparable to that of a pristine Au electrode. Best P3HT or PC12TV12T OFETs with 5 nm thick V2O5 on Mo electrode show the charge carrier mobility of 0.12 and 0.38 cm(2)/(V s), respectively. Ultraviolet photoelectron spectroscopy results exhibited the work-function of the Mo electrode progressively changed from 4.3 to 4.9 eV with an increase in V2O5 thickness from 0 to 5 nm, respectively. Interestingly, the V2O5-deposited Mo exhibits comparable Rc to Au, which mainly results from the decreased barrier height for hole carrier injection from the low-cost metal electrode to the frontier molecular orbital of the p-type polymer semiconductor after the incorporation of the transition metal oxide hole injection layer, such as V2O5. This enables the development of large-area, low-cost electronics with the Mo electrodes and V2O5 interlayer.

Risk Factors Associated with Unsafe Injection Practices at the First Injection Episode among Intravenous Drug Users in France: Results from PrimInject, an Internet Survey.

Science.gov (United States)

Guichard, Anne; Guignard, Romain; Lert, France; Roy, Elise

2015-01-01

Background. New drug use patterns may increase the risk of human immunodeficiency virus and hepatitis infections. In France, new injection patterns among youths with diverse social backgrounds have emerged, which may explain the persistently high rates of hepatitis C virus infection. This study explores factors associated with injection risk behaviours at first injection among users who began injecting in the post-2000 era. Methods. A cross-sectional study was conducted on the Internet from October 2010 to March 2011, through an online questionnaire. Multivariate logistic regression identified the independent correlates of needle sharing and equipment (cooker/cotton filter) sharing. Results. Among the 262 respondents (mean age 25 years), 65% were male. Both risk behaviours were positively associated with initiation before 18 years of age (aOR 3.7 CI 95% 1.3-10.6 and aOR 3.0 CI 95% 1.3-7.0) and being injected by another person (aOR 3.1 CI 95% 1.0-9.9 and aOR 3.0 CI 95% 1.3-7.1). Initiation at a party was an independent correlate of equipment sharing (aOR 2.6 95% CI 1.0-6.8). Results suggest a need for innovative harm reduction programmes targeting a variety of settings and populations, including youths and diverse party scenes. Education of current injectors to protect both themselves and those they might initiate into injection is critically important.

Risk Factors Associated with Unsafe Injection Practices at the First Injection Episode among Intravenous Drug Users in France: Results from PrimInject, an Internet Survey

Directory of Open Access Journals (Sweden)

Anne Guichard

2015-01-01

Full Text Available Background. New drug use patterns may increase the risk of human immunodeficiency virus and hepatitis infections. In France, new injection patterns among youths with diverse social backgrounds have emerged, which may explain the persistently high rates of hepatitis C virus infection. This study explores factors associated with injection risk behaviours at first injection among users who began injecting in the post-2000 era. Methods. A cross-sectional study was conducted on the Internet from October 2010 to March 2011, through an online questionnaire. Multivariate logistic regression identified the independent correlates of needle sharing and equipment (cooker/cotton filter sharing. Results. Among the 262 respondents (mean age 25 years, 65% were male. Both risk behaviours were positively associated with initiation before 18 years of age (aOR 3.7 CI 95% 1.3–10.6 and aOR 3.0 CI 95% 1.3–7.0 and being injected by another person (aOR 3.1 CI 95% 1.0–9.9 and aOR 3.0 CI 95% 1.3–7.1. Initiation at a party was an independent correlate of equipment sharing (aOR 2.6 95% CI 1.0–6.8. Conclusions. Results suggest a need for innovative harm reduction programmes targeting a variety of settings and populations, including youths and diverse party scenes. Education of current injectors to protect both themselves and those they might initiate into injection is critically important.

COLLISIONLESS ELECTRON–ION SHOCKS IN RELATIVISTIC UNMAGNETIZED JET–AMBIENT INTERACTIONS: NON-THERMAL ELECTRON INJECTION BY DOUBLE LAYER

International Nuclear Information System (INIS)

Ardaneh, Kazem; Cai, Dongsheng; Nishikawa, Ken-Ichi

2016-01-01

The course of non-thermal electron ejection in relativistic unmagnetized electron–ion shocks is investigated by performing self-consistent particle-in-cell simulations. The shocks are excited through the injection of a relativistic jet into ambient plasma, leading to two distinct shocks (referred to as the trailing shock and leading shock) and a contact discontinuity. The Weibel-like instabilities heat the electrons up to approximately half of the ion kinetic energy. The double layers formed in the trailing and leading edges then accelerate the electrons up to the ion kinetic energy. The electron distribution function in the leading edge shows a clear, non-thermal power-law tail which contains ∼1% of electrons and ∼8% of the electron energy. Its power-law index is −2.6. The acceleration efficiency is ∼23% by number and ∼50% by energy, and the power-law index is −1.8 for the electron distribution function in the trailing edge. The effect of the dimensionality is examined by comparing the results of three-dimensional simulations with those of two-dimensional simulations. The comparison demonstrates that electron acceleration is more efficient in two dimensions.

Design Of A Bi-Functional α-Fe2O3/Zn2SiO4:Mn2+ By Layer-By-Layer Assembly Method

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Yu Ri

2015-06-01

Full Text Available This work describes the design of bi-functional α-Fe2O3/Zn2SiO4:Mn2+ using a two-step coating process. We propose a combination of pigments (α-Fe2O3 and phosphor (Zn2SiO4:Mn2+ glaze which is assembled using a layer-by-layer method. A silica-coated α-Fe2O3 pigment was obtained by a sol-gel method and a Zn2+ precursor was then added to the silica-coated α-Fe2O3 to create a ZnO layer. Finally, the Zn2SiO4:Mn2+ layer was prepared with the addition of Mn2+ ions to serve as a phosphor precursor in the multi-coated α-Fe2O3, followed by annealing at a temperature above 1000°C. Details of the phase structure, color and optical properties of the multi-functional α-Fe2O3/Zn2SiO4:Mn2+ were characterized by transmission electron microscopy and X-ray diffraction analyses.

Interfacial crystalline structures in injection over-molded polypropylene and bond strength.

Science.gov (United States)

Yan, Bowen; Wu, Hong; Jiang, Genjie; Guo, Shaoyun; Huang, Jian

2010-11-01

This paper describes interfacial crystalline structures found in injection overmolded polypropylene components and the relationship of these structures to bond strength between the components. The combined effects of the development of hierarchical gradient structures and the particular thermomechanical environment near the interface on the interfacial crystalline structures were investigated in detail by PLM, SEM, DSC, WAXD, and infrared dichroism spectroscopy. The experimental results showed that during molding there was competitive formation of interfacial crystalline structures consisted of "shish-kebab" layer (SKL) and a transcrystalline layers (TCL). Variation in shear stress (controlled by injection pressure and injection speed) plays an important role in the formation of the SKL. The formation of TCL is influenced by the thermal environment, namely melt temperature and mold temperature. Increasing within certain limits, interfacial temperature and the thermal gradient near the interface promotes β-iPP growth. The relationship between interfacial crystalline structures and interfacial bond strength was established by lap shear measurement. The interfacial bond strength is improved by enhancing the formation of TCL, but reduced if SKL predominates.

Results on powder injection molding of Ni[sub 3]Al and application to other intermetallic compositions

Energy Technology Data Exchange (ETDEWEB)

Cooper, R.M.

1992-01-01

Net forming processes are under development to allow affordable production of intermetallic components. Powder injection molding (PIM) mav be employed for the production of complex-shaped intermetallic geometries. Proper choice of powder parameters and processing conditions can lead to the formation of fullv dense structures through pressure-less sintering. In this study, Ni[sub 3]Al with 0.04 wt.-% boron has been successfully injection molded and sintered to full density. A yield strength of 340 MPa, ultimate tensile strength (UTS) of 591 MPa, and 8% elongation were attained for injection molded and sintered tensile bars. Powder characteristics and sintering behavior are given for the nickel aluminide employed in this study to highlight the powder attributes needed for injection molding. Molding parameters, debinding and sintering schedules, along, with mechanical properties are presented to indicate the viability of PIM for intermetallics. This approach based on the understanding of key powder characteristics and use of the reactive synthesis powder process mav be extended to the successful injection molding of other intermetallic systems.

Results on powder injection molding of Ni{sub 3}Al and application to other intermetallic compositions

Energy Technology Data Exchange (ETDEWEB)

Cooper, R.M.

1992-12-31

Net forming processes are under development to allow affordable production of intermetallic components. Powder injection molding (PIM) mav be employed for the production of complex-shaped intermetallic geometries. Proper choice of powder parameters and processing conditions can lead to the formation of fullv dense structures through pressure-less sintering. In this study, Ni{sub 3}Al with 0.04 wt.-% boron has been successfully injection molded and sintered to full density. A yield strength of 340 MPa, ultimate tensile strength (UTS) of 591 MPa, and 8% elongation were attained for injection molded and sintered tensile bars. Powder characteristics and sintering behavior are given for the nickel aluminide employed in this study to highlight the powder attributes needed for injection molding. Molding parameters, debinding and sintering schedules, along, with mechanical properties are presented to indicate the viability of PIM for intermetallics. This approach based on the understanding of key powder characteristics and use of the reactive synthesis powder process mav be extended to the successful injection molding of other intermetallic systems.

Effect of Al 2 O 3 Recombination Barrier Layers Deposited by Atomic Layer Deposition in Solid-State CdS Quantum Dot-Sensitized Solar Cells

KAUST Repository

Roelofs, Katherine E.

2013-03-21

Despite the promise of quantum dots (QDs) as a light-absorbing material to replace the dye in dye-sensitized solar cells, quantum dot-sensitized solar cell (QDSSC) efficiencies remain low, due in part to high rates of recombination. In this article, we demonstrate that ultrathin recombination barrier layers of Al2O3 deposited by atomic layer deposition can improve the performance of cadmium sulfide (CdS) quantum dot-sensitized solar cells with spiro-OMeTAD as the solid-state hole transport material. We explored depositing the Al2O3 barrier layers either before or after the QDs, resulting in TiO2/Al2O3/QD and TiO 2/QD/Al2O3 configurations. The effects of barrier layer configuration and thickness were tracked through current-voltage measurements of device performance and transient photovoltage measurements of electron lifetimes. The Al2O3 layers were found to suppress dark current and increase electron lifetimes with increasing Al 2O3 thickness in both configurations. For thin barrier layers, gains in open-circuit voltage and concomitant increases in efficiency were observed, although at greater thicknesses, losses in photocurrent caused net decreases in efficiency. A close comparison of the electron lifetimes in TiO2 in the TiO2/Al2O3/QD and TiO2/QD/Al2O3 configurations suggests that electron transfer from TiO2 to spiro-OMeTAD is a major source of recombination in ss-QDSSCs, though recombination of TiO2 electrons with oxidized QDs can also limit electron lifetimes, particularly if the regeneration of oxidized QDs is hindered by a too-thick coating of the barrier layer. © 2013 American Chemical Society.

ELM elimination with Li powder injection in EAST discharges using the tungsten upper divertor

Science.gov (United States)

Maingi, R.; Hu, J. S.; Sun, Z.; Tritz, K.; Zuo, G. Z.; Xu, W.; Huang, M.; Meng, X. C.; Canik, J. M.; Diallo, A.; Lunsford, R.; Mansfield, D. K.; Osborne, T. H.; Gong, X. Z.; Wang, Y. F.; Li, Y. Y.; EAST Team

2018-02-01

We report the first successful use of lithium (Li) to eliminate edge-localized modes (ELMs) with tungsten divertor plasma-facing components in the EAST device. Li powder injected into the scrape-off layer of the tungsten upper divertor successfully eliminated ELMs for 3-5 s in EAST. The ELM elimination became progressively more effective in consecutive discharges at constant lithium delivery rates, and the divertor D α baseline emission was reduced, both signatures of improved wall conditioning. A modest decrease in stored energy and normalized energy confinement was also observed, but the confinement relative to H98 remained well above 1, extending the previous ELM elimination results via Li injection into the lower carbon divertor in EAST (Hu et al 2015 Phys. Rev. Lett. 114 055001). These results can be compared with recent observations with lithium pellets in ASDEX-Upgrade that failed to mitigate ELMs (Lang et al 2017 Nucl. Fusion 57 016030), highlighting one comparative advantage of continuous powder injection for real-time ELM elimination.

Assessment of injection safety in Ha Dong General Hospital, Hanoi, in 2012 [version 3; referees: 2 approved

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Phan Van Tuong

2017-09-01

Full Text Available Background: Injection is one of the most frequently used medical methods to introduce drugs or other substances into the body for purposes of treatment or prevention. Unsafe injection can cause adverse outcomes, such as abscess and anaphylactic shock, and increases the risk of blood-borne transmission of viruses to patients and health care workers, as well as the community. Recognizing the importance of injection safety, in 2000 the Vietnamese Ministry of Health (MOH collaborated with the Vietnam Nurses Association to launch the “Safe injection” program throughout the country, including Hanoi. Methods: This cross-sectional study, combining quantitative and qualitative analysis, was conducted from February to August 2012 in Ha Dong General Hospital using a structured questionnaire and observation checklist. The target population of the study was 109 nurses working in clinical departments and 436 injections were observed. Results: The percentage of nurses who are familiar with injection safety standards was found to be 82.6%. The proportion of practical injections that met the 23 standards of injection safety set by the MOH amounted to 22.2%. The factors related to safe injection practice of nurses who are younger age group (OR=3.1; p<0.05 and lower amount of working years (OR=2.8; p<0.05. Conclusions: Despite the high level of knowledge about safety injection, a low proportion of nurses performed correct safety injection practice. Moreover, the results demonstrated that experience might not always guarantee better practice. The findings raise the need for further training about this issue, especially among older nurses.

Glenohumeral Joint Injections

Science.gov (United States)

Gross, Christopher; Dhawan, Aman; Harwood, Daniel; Gochanour, Eric; Romeo, Anthony

2013-01-01

Context: Intra-articular injections into the glenohumeral joint are commonly performed by musculoskeletal providers, including orthopaedic surgeons, family medicine physicians, rheumatologists, and physician assistants. Despite their frequent use, there is little guidance for injectable treatments to the glenohumeral joint for conditions such as osteoarthritis, adhesive capsulitis, and rheumatoid arthritis. Evidence Acquisition: We performed a comprehensive review of the available literature on glenohumeral injections to help clarify the current evidence-based practice and identify deficits in our understanding. We searched MEDLINE (1948 to December 2011 [week 1]) and EMBASE (1980 to 2011 [week 49]) using various permutations of intra-articular injections AND (corticosteroid OR hyaluronic acid) and (adhesive capsulitis OR arthritis). Results: We identified 1 and 7 studies that investigated intra-articular corticosteroid injections for the treatment of osteoarthritis and adhesive capsulitis, respectively. Two and 3 studies investigated the use of hyaluronic acid in osteoarthritis and adhesive capsulitis, respectively. One study compared corticosteroids and hyaluronic acid injections in the treatment of osteoarthritis, and another discussed adhesive capsulitis. Conclusion: Based on existing studies and their level of evidence, there is only expert opinion to guide corticosteroid injection for osteoarthritis as well as hyaluronic acid injection for osteoarthritis and adhesive capsulitis. PMID:24427384

Promoting Safe Injection Practices : The Challenge Ahead

Directory of Open Access Journals (Sweden)

V K Srivastava

2006-06-01

Full Text Available Injections are one of the most common health care procedures in the world. Global estimates range between 12 billion-16 billion injections each year’. Most of the injections (90 to 95% are given for therapeutic purposes and only 5 to 10% are given for immunization. It is estimated that worldwide every year a billion injections are given to women and children for immunization. Up to half of these injections are currently thought to be unsafe. Due to the sheer burden of injections and the coresponding magnitude of unsafe injections, the proportion of blood borne pathogen transmission is much larger than is due to unsafe blood transfusion. Unsafe injections are responsible for million cases of Hepatitis B and C and an estimated one-quarter of a million cases of HIV annually. Worldwide 8 to 16 million hepatitis B, 2.3 - 4.7 million hepatitis C and 80,000 - 1,60,000 HIV infections are estimated to occur yearly form reuse of syringes and needles without adequate sterilization2. In the less developed countries, the unsafe injection practices account for an estimated $ 535 million in health care costs and result in nearly 1.3 million deaths a year. In a developing country like India where unnecessary injections are common, the total bur­den of injections is estimated to be 3.7 billion injections per year3. Certain studies that have been carried out in India,along with anecdotal evidence point towards a large numbe- of unnecessary, inappropriate, unsafe injections and inadequate sharps waste management4 5. A high proportion of injections given in India for immunization are unsafe due to reuse of needles/ syringes. The popularity of curative injections remains high due to various factors influencing the behaviour of prescribers / injection givers as well as clients.

Nanoporous layered silicate AMH-3/cellulose acetate nanocomposite membranes for gas separations

KAUST Repository

Kim, Wun-gwi

2013-08-01

Nanoporous layered silicate/polymer composite membranes are of interest because they can exploit the high aspect ratio of exfoliated selective flakes/layers to enhance molecular sieving and create a highly tortuous transport path for the slower molecules. In this work, we combine membrane synthesis, detailed microstructural characterization, and mixed gas permeation measurements to demonstrate that nanoporous flake/polymer membranes allows significant improvement in gas permeability while maintaining selectivity. We begin with the primary-amine-intercalated porous layered silicate SAMH-3 and show that it can be exfoliated using a high shear rate generated by a high-speed mixer. The exfoliated SAMH-3 flakes were used to form SAMH-3/cellulose acetate (CA) membranes. Their microstructure was analyzed by small angle X-ray scattering (SAXS), revealing a high degree of exfoliation of AMH-3 layers in the CA membrane with a small number of layers (4-8) in the exfoliated flakes. TEM analysis visualized the thickness of the flakes as 15-30nm, and is consistent with the SAXS analysis. The CO2/CH4 gas separation performance of the CA membrane was significantly increased by incorporating only 2-6wt% of SAMH-3 flakes. There was a large increase in CO2 permeability with maintenance of selectivity. This cannot be explained by conventional models of transport in flake-containing membranes, and indicates complex transport paths in the membrane. It is also in contrast to the much higher loadings of isotropic particles required for similar enhancements. The present approach may allow avoidance of particle aggregation and poor interfacial adhesion associated with larger quantities of inorganic fillers. © 2013 Elsevier B.V.

Towards spin injection into silicon

Energy Technology Data Exchange (ETDEWEB)

Dash, S.P.

2007-08-15

Si has been studied for the purpose of spin injection extensively in this thesis. Three different concepts for spin injection into Si have been addressed: (1) spin injection through a ferromagnet-Si Schottky contact, (2) spin injection using MgO tunnel barriers in between the ferromagnet and Si, and (3) spin injection from Mn-doped Si (DMS) as spin aligner. (1) FM-Si Schottky contact for spin injection: To be able to improve the interface qualities one needs to understand the atomic processes involved in the formation of silicide phases. In order to obtain more detailed insight into the formation of such phases the initial stages of growth of Co and Fe were studied in situ by HRBS with monolayer depth resolution.(2) MgO tunnel barrier for spin injection into Si: The fabrication and characterization of ultra-thin crystalline MgO tunnel barriers on Si (100) was presented. (3) Mn doped Si for spin injection: Si-based diluted magnetic semiconductor samples were prepared by doping Si with Mn by two different methods i) by Mn ion implantation and ii) by in-diffusion of Mn atoms (solid state growth). (orig.)

Anisotropic carrier mobility in single- and bi-layer C3N sheets

Science.gov (United States)

Wang, Xueyan; Li, Qingfang; Wang, Haifeng; Gao, Yan; Hou, Juan; Shao, Jianxin

2018-05-01

Based on the density functional theory combined with the Boltzmann transport equation with relaxation time approximation, we investigate the electronic structure and predict the carrier mobility of single- and bi-layer newly fabricated 2D carbon nitrides C3N. Although C3N sheets possess graphene-like planar hexagonal structure, the calculated carrier mobility is remarkably anisotropic, which is found mainly induced by the anisotropic effective masses and deformation potential constants. Importantly, we find that both the electron and hole mobilities are considerable high, for example, the hole mobility along the armchair direction of single-layer C3N sheets can arrive as high as 1.08 ×104 cm2 V-1 s-1, greatly larger than that of C2N-h2D and many other typical 2D materials. Owing to the high and anisotropic carrier mobility and appropriate band gap, single- and bi-layer semiconducting C3N sheets may have great potential applications in high performance electronic and optoelectronic devices.

[Influence of MnO3 on Photoelectric Performance in Organic Light Emitting Diodes].

Science.gov (United States)

Guan, Yun-xia; Chen, Li-jia; Chen, Ping; Fu, Xiao-qiang; Niu, Lian-bin

2016-03-01

Organic Light Emitting Diodes (OLEDs) has been a promising new research point that has received much attention recently. Emission in a conventional OLED originates from the recombination of carriers (electrons and holes) that are injected from external electrodes. In the device, Electrons, on the other hand, are injected from the Al cathode to an electron-transporting layer and travel to the same emissive zone. Holes are injected from the transparent ITO anode to a hole-transporting layer and holes reach an emitting zone through the holetransporting layer. Electrons and holes recombine at the emissive film to formsinglet excited states, followed by emissive light. It is because OLED is basically an optical device and its structure consists of organic or inorganic layers of sub-wavelength thickness with different refractive indices. When the electron and holes are injected through the electrodes, they combine in the emission zone emitting the photons. These photons will have the reflection and transmission at each interface and the interference will determine the intensity profile. The emissive light reflected at the interfaces or the metallic electrode returns to the emissive layer and affects the radiation current efficiency. Microcavity OLED can produce saturated colors and narrow the emission spetrum as a new kind of technique. In the paper, we fabricate microcavity OLED using glass substrate. Ag film acts as the anode reflector mirror; NPB serves as the hole-transporting material; Alq3 is electron-transporting material and organic emissive material; Ag film acts as cathode reflector mirror. The microcavity OLED structures named as A, B, C and D are glass/Ag(15 nm)/MoO3 (x nm)/NPB(50 nm)/Alq3 (60 nm)/A1(100 nm). Here, A, x = 4 nm; B, x = 7 nm; C, x = 10 nm; D, x = 13 nm. The characteristic voltage, brightness and current of these devices are investigated in the electric field. The luminance from the Devices A, B, C and D reaches the luminance of 928, 1 369, 2

Surface characterisation and functionalisation of indium tin oxide anodes for improvement of charge injection in organic light emitting diodes

International Nuclear Information System (INIS)

Davenas, J.; Besbes, S.; Abderrahmen, A.; Jaffrezic, N.; Ben Ouada, H.

2008-01-01

Wettability studies have been performed to probe the surface properties of ITO substrates, aimed to be used as hole injecting electrode in OLEDs. The elimination of organic contaminants upon the cleaning treatment (ultrasonic bath in organic solvents) leads to an increase of the free energy of the ITO surface becoming hydrophilic. The surface energy components calculated from the Van Oss model show the appearance of a basic component upon the cleaning treatment. A thermal treatment at 100 deg. C for 3 h leads to a decrease of the surface free energy due to surface dehydration. These properties are attributed to the hydroxides formed at the ITO surface inducing improved adhesion at the ITO/polymer interface. The ITO surfaces have been functionalised with a chloroethylphosphonic acid mono-layer to increase their stability. The appearance of an acid-base component leads to a dipolar character of the ITO surface. The formation of a compact layer of a spin coated poly(phenylenevinylene) derivative induces the shielding of the ITO basic character. The weakening of the near infrared absorption associated to ITO free carriers confirms the formation of a dipole layer at the interface with the molecular layer in contact with ITO. Improved injection properties, shown by the current/voltage characteristics, result from the interface modifications

Nonlinear and Nonequilibrium Spin Injection in Magnetic Tunneling Junctions

Science.gov (United States)

Guo, Hong

2007-03-01

Quantitative analysis of charge and spin quantum transport in spintronic devices requires an atomistic first principles approach that can handle nonlinear and nonequilibrium transport conditions. We have developed an approach for this purpose based on real space density functional theory (DFT) carried out within the Keldysh nonequilibrium Green's function formalism (NEGF). We report theoretical analysis of nonlinear and nonequilibrium spin injection and quantum transport in Fe/MgO/Fe trilayer structures as a function of external bias voltage. Devices with well relaxed atomic structures and with FeO oxidization layers are investigated as a function of external bias voltage. We also report calculations of nonequilibrium spin injection into molecular layers and graphene. Comparisons to experimental data will be presented. Work in collaborations with: Derek Waldron, Vladimir Timochevski (McGill University); Ke Xia (Institute of Physics, Chinese Academy of Science, Beijing, China); Eric Zhu, Jian Wang (University of Hong Kong); Paul Haney, and Allan MacDonald (University of Texas at Austin).

Hybrid diffusion-P3 equation in N-layered turbid media: steady-state domain.

Science.gov (United States)

Shi, Zhenzhi; Zhao, Huijuan; Xu, Kexin

2011-10-01

This paper discusses light propagation in N-layered turbid media. The hybrid diffusion-P3 equation is solved for an N-layered finite or infinite turbid medium in the steady-state domain for one point source using the extrapolated boundary condition. The Fourier transform formalism is applied to derive the analytical solutions of the fluence rate in Fourier space. Two inverse Fourier transform methods are developed to calculate the fluence rate in real space. In addition, the solutions of the hybrid diffusion-P3 equation are compared to the solutions of the diffusion equation and the Monte Carlo simulation. For the case of small absorption coefficients, the solutions of the N-layered diffusion equation and hybrid diffusion-P3 equation are almost equivalent and are in agreement with the Monte Carlo simulation. For the case of large absorption coefficients, the model of the hybrid diffusion-P3 equation is more precise than that of the diffusion equation. In conclusion, the model of the hybrid diffusion-P3 equation can replace the diffusion equation for modeling light propagation in the N-layered turbid media for a wide range of absorption coefficients.

Comparison of organic light emitting diodes with different mixed layer structures

Energy Technology Data Exchange (ETDEWEB)

Kee, Y.Y.; Siew, W.O. [Faculty of Engineering, Multimedia University, 63100 Cyberjaya (Malaysia); Yap, S.S. [Faculty of Engineering, Multimedia University, 63100 Cyberjaya (Malaysia); Faculty of Engineering, University of Malaya, 50603 Kuala Lumpur (Malaysia); Tou, T.Y., E-mail: tytou@mmu.edu.my [Faculty of Engineering, Multimedia University, 63100 Cyberjaya (Malaysia)

2014-11-03

A mixed-source thermal evaporation method was used to fabricate organic light emitting diodes (OLEDs) with uniformly mixed (UM), continuously graded mixed (CGM) and step-wise graded, mixed (SGM) light-emitting layers. N,N′-Bis(3-methylphenyl)-N,N′-diphenylbenzidine and Tris-(8-hydroxyquinoline)aluminum were used, respectively, as the hole- and electron-transport materials. As compared to the conventional, heterojunction OLED, the maximum brightness of UM-, CGM- and SGM-OLEDs without charge injection layers were improved by 2.2, 3.8 and 2.1 times, respectively, while the maximum power efficiencies improved by 1.5, 3.2 and 1.9 times. These improvements were discussed in terms of more distributed recombination zone and removal of interfacial barrier. - Highlights: • Fabrication of OLEDs using a mixed-source evaporation technique • Three different types of mixed-host OLEDs with better brightness • Improved electroluminescence and power efficiencies as compared to conventional OLED.

Patterns of labeling of intraspinal reactive cells in rats injected with [3H]thymidine prior to or following sciatic axotomy

International Nuclear Information System (INIS)

Gilmore, S.A.; Walls, R.C.

1981-01-01

Labeling patterns of reactive cells which occur in the spinal cord following sciatic axotomy were investigated by autoradiography following administration of [ 3 H]thymidine (2 μCi/g body weight/injection). In this investigation the labeling patterns in reactive cells were compared when [ 3 H]thymidine was injected: (1) prior to or (2) following surgery. Immature rats underwent sciatic axotomy and were killed 3 days later (20 days of age). Some of their littermates served as sham-operated controls, and others were killed on the day of surgery to evaluate intraspinal labeling at that time. In one series of animals, a single injection of [ 3 H]thymidine was administered 2 h prior to autopsy. This procedure resulted in heavy labeling of 6.2% of the cells classified as reactive cells. In the second series, 3 injections of [ 3 H]thymidine were given on the day prior to surgery. On the third post-operative day, 19.4% of the reactive cells were labeled, and the majority of these were lightly labeled, suggesting that they had undergone several cell divisions. The data from both injection protocols indicate that the magnitude of the cellular response to axotomy would be markedly underestimated, if one were to consider only labeled cells. The present investigators concluded that these particular applications of [ 3 H]thymidine autoradiography provide valuable information on reactions of the central nervous system to injury but are of little value in determining origins of the reactive cells. (Auth.)

Atomic layer-deposited Al–HfO{sub 2}/SiO{sub 2} bi-layers towards 3D charge trapping non-volatile memory

Energy Technology Data Exchange (ETDEWEB)

Congedo, Gabriele, E-mail: gabriele.congedo@mdm.imm.cnr.it; Wiemer, Claudia; Lamperti, Alessio; Cianci, Elena; Molle, Alessandro; Volpe, Flavio G.; Spiga, Sabina, E-mail: sabina.spiga@mdm.imm.cnr

2013-04-30

A metal/oxide/high-κ dielectric/oxide/silicon (MOHOS) planar charge trapping memory capacitor including SiO{sub 2} as tunnel oxide, Al–HfO{sub 2} as charge trapping layer, SiO{sub 2} as blocking oxide and TaN metal gate was fabricated and characterized as test vehicle in the view of integration into 3D cells. The thin charge trapping layer and blocking oxide were grown by atomic layer deposition, the technique of choice for the implementation of these stacks into 3D structures. The oxide stack shows a good thermal stability for annealing temperature of 900 °C in N{sub 2}, as required for standard complementary metal–oxide–semiconductor processes. MOHOS capacitors can be efficiently programmed and erased under the applied voltages of ± 20 V to ± 12 V. When compared to a benchmark structure including thin Si{sub 3}N{sub 4} as charge trapping layer, the MOHOS cell shows comparable program characteristics, with the further advantage of the equivalent oxide thickness scalability due to the high dielectric constant (κ) value of 32, and an excellent retention even for strong testing conditions. Our results proved that high-κ based oxide structures grown by atomic layer deposition can be of interest for the integration into three dimensionally stacked charge trapping devices. - Highlights: ► Charge trapping device with Al–HfO{sub 2} storage layer is fabricated and characterized. ► Al–HfO{sub 2} and SiO{sub 2} blocking oxides are deposited by atomic layer deposition. ► The oxide stack shows a good thermal stability after annealing at 900 °C. ► The device can be efficiently programmed/erased and retention is excellent. ► The oxide stack could be used for 3D-stacked Flash non-volatile memories.

Layer- and column-specific knockout of NMDA receptors in pyramidal neurons of the mouse barrel cortex.

Directory of Open Access Journals (Sweden)

Rachel Aronoff

2007-11-01

Full Text Available Viral vectors injected into the mouse brain offer the possibility for localized genetic modifications in a highly controlled manner. Lentivector injection into mouse neocortex transduces cells within a diameter of approximately 200µm, which closely matches the lateral scale of a column in barrel cortex. The depth and volume of the injection determines which cortical layer is transduced. Furthermore, transduced gene expression from the lentivector can be limited to predominantly pyramidal neurons by using a 1.3kb fragment of the αCaMKII promoter. This technique therefore allows genetic manipulation of a specific cell type in defined columns and layers of the neocortex. By expressing Cre recombinase from such a lentivector in gene-targeted mice carrying a floxed gene, highly specific genetic lesions can be induced. Here, we demonstrate the utility of this approach by specifically knocking out NMDA receptors (NMDARs in pyramidal neurons in the somatosensory barrel cortex of gene-targeted mice carrying floxed NMDAR 1 genes. Neurons transduced with lentivector encoding GFP and Cre recombinase exhibit not only reductions in NMDAR 1 mRNA levels, but reduced NMDAR-dependent currents and pairing-induced synaptic potentiation. This technique for knockout of NMDARs in a cell type, column- and layer-specific manner in the mouse somatosensory cortex may help further our understanding of the functional roles of NMDARs in vivo during sensory perception and learning.

Interface properties of bilayer structure Alq{sub 3}/Fe{sub 65}Co{sub 35}

Energy Technology Data Exchange (ETDEWEB)

Wang, Zhen, E-mail: wangzhen@chd.edu.cn [Department of Applied Physics, Chang’an University, Xi’an 710064 (China); Xu, Chunlong; Wang, Jinguo; Chang, Qiaoli [Department of Applied Physics, Chang’an University, Xi’an 710064 (China); Zuo, Yalu; Xi, Li [Key Laboratory for Magnetism and Magnetic Materials of Ministry of Education, Lanzhou University, Lanzhou 730000 (China)

2015-04-01

Highlights: • Bilayer structure of Alq{sub 3}/FeCo was fabricated in a dual ultra high vacuum chamber. • Organic layer reacts partially with the FeCo film. • Electronic injection barrier is 0.76 eV in the interface. • The induced uniaxial anisotropy appears in Alq{sub 3}/FeCo. - Abstract: The interface between the organic and magnetic electrodes is a fundamental problem in organic spintronics devices. Therefore, bilayer structure of Alq{sub 3}/FeCo was fabricated in a dual ultra high vacuum chamber. The electronic structure of Alq{sub 3}–FeCo interface has been studied by X-ray photoelectron spectroscopy and ultraviolet photoelectron spectroscopy with Argon ion etching technique. It was found that organic layer reacts partially with the FeCo film, forming complex binding of metallic carbide and/or oxidation state in the interfacial region. Electronic injection barrier is 0.76 eV in the interface. The structural variation of the contact region is proposed to be one of the possible factors resulting in spin-injection failure. The magnetic properties of FeCo film with different thicknesses on glass substrate and Alq{sub 3} layer are also investigated. The induced uniaxial anisotropy only presents in 3 nm FeCo thickness for glass/FeCo, while it appears in 3–5 nm FeCo for Alq{sub 3}/FeCo.

Spin injection and transport in semiconductor and metal nanostructures

Science.gov (United States)

Zhu, Lei

In this thesis we investigate spin injection and transport in semiconductor and metal nanostructures. To overcome the limitation imposed by the low efficiency of spin injection and extraction and strict requirements for retention of spin polarization within the semiconductor, novel device structures with additional logic functionality and optimized device performance have been developed. Weak localization/antilocalization measurements and analysis are used to assess the influence of surface treatments on elastic, inelastic and spin-orbit scatterings during the electron transport within the two-dimensional electron layer at the InAs surface. Furthermore, we have used spin-valve and scanned probe microscopy measurements to investigate the influence of sulfur-based surface treatments and electrically insulating barrier layers on spin injection into, and spin transport within, the two-dimensional electron layer at the surface of p-type InAs. We also demonstrate and analyze a three-terminal, all-electrical spintronic switching device, combining charge current cancellation by appropriate device biasing and ballistic electron transport. The device yields a robust, electrically amplified spin-dependent current signal despite modest efficiency in electrical injection of spin-polarized electrons. Detailed analyses provide insight into the advantages of ballistic, as opposed to diffusive, transport in device operation, as well as scalability to smaller dimensions, and allow us to eliminate the possibility of phenomena unrelated to spin transport contributing to the observed device functionality. The influence of the device geometry on magnetoresistance of nanoscale spin-valve structures is also demonstrated and discussed. Shortcomings of the simplified one-dimensional spin diffusion model for spin valve are elucidated, with comparison of the thickness and the spin diffusion length in the nonmagnetic channel as the criterion for validity of the 1D model. Our work contributes

Swine manure injection with low-disturbance applicator and cover crops reduce phosphorus losses.

Science.gov (United States)

Kovar, J L; Moorman, T B; Singer, J W; Cambardella, C A; Tomer, M D

2011-01-01

Injection of liquid swine manure disturbs surface soil so that runoff from treated lands can transport sediment and nutrients to surface waters. We determined the effect of two manure application methods on P fate in a corn (Zea mays L.)-soybean [Glycine max (L.) Merr.] production system, with and without a winter rye (Secale cereale L.)-oat (Avena sativa L.) cover crop. Treatments included: (i) no manure; (ii) knife injection; and (iii) low-disturbance injection, each with and without the cover crop. Simulated rainfall runoff was analyzed for dissolved reactive P (DRP) and total P (TP). Rainfall was applied 8 d after manure application (early November) and again in May after emergence of the corn crop. Manure application increased soil bioavailable P in the 20- to 30-cm layer following knife injection and in the 5- to 20-cm layer following low-disturbance injection. The low-disturbance system caused less damage to the cover crop, so that P uptake was more than threefold greater. Losses of DRP were greater in both fall and spring following low-disturbance injection; however, application method had no effect on TP loads in runoff in either season. The cover crop reduced fall TP losses from plots with manure applied by either method. In spring, DRP losses were significantly higher from plots with the recently killed cover crop, but TP losses were not affected. Low-disturbance injection of swine manure into a standing cover crop can minimize plant damage and P losses in surface runoff while providing optimum P availability to a subsequent agronomic crop.

Stability Analysis of High-Speed Boundary-Layer Flow with Gas Injection

Science.gov (United States)

2014-06-01

laminar-turbulent transition on slender bodies in a hypersonic flow at small angles of attack is caused by amplification of acoustic waves trapped in...x decreases and slowly approaches the no-blow distribution. These CFD data demonstrate that the injection strongly affects the near-wall flow...conclusion. Figure 10 shows that the spatial growth rates ( )  are maximal for mode 0 corresponding to the Mack second mode – typical for hypersonic

Open-Source-Based 3D Printing of Thin Silica Gel Layers in Planar Chromatography.

Science.gov (United States)

Fichou, Dimitri; Morlock, Gertrud E

2017-02-07

On the basis of open-source packages, 3D printing of thin silica gel layers is demonstrated as proof-of-principle for use in planar chromatography. A slurry doser was designed to replace the plastic extruder of an open-source Prusa i3 printer. The optimal parameters for 3D printing of layers were studied, and the planar chromatographic separations on these printed layers were successfully demonstrated with a mixture of dyes. The layer printing process was fast. For printing a 0.2 mm layer on a 10 cm × 10 cm format, it took less than 5 min. It was affordable, i.e., the running costs for producing such a plate were less than 0.25 Euro and the investment costs for the modified hardware were 630 Euro. This approach demonstrated not only the potential of the 3D printing environment in planar chromatography but also opened new avenues and new perspectives for tailor-made plates, not only with regard to layer materials and their combinations (gradient plates) but also with regard to different layer shapes and patterns. As such an example, separations on a printed plane layer were compared with those obtained from a printed channeled layer. For the latter, 40 channels were printed in parallel on a 10 cm × 10 cm format for the separation of 40 samples. For producing such a channeled plate, the running costs were below 0.04 Euro and the printing process took only 2 min. All modifications of the device and software were released open-source to encourage reuse and improvements and to stimulate the users to contribute to this technology. By this proof-of-principle, another asset was demonstrated to be integrated into the Office Chromatography concept, in which all relevant steps for online miniaturized planar chromatography are performed by a single device.

[(CH3)3NCH2CH2NH3]SnI4: a layered perovskite with quaternary/primary ammonium dications and short interlayer iodine-iodine contacts.

Science.gov (United States)

Xu, Zhengtao; Mitzi, David B; Medeiros, David R

2003-03-10

The organic-inorganic hybrid [(CH(3))(3)NCH(2)CH(2)NH(3)]SnI(4) presents a layered perovskite structure, templated by an organic dication containing both a primary and a quaternary ammonium group. Due to the high charge density and small size of the organic cation, the separation of the perovskite layers is small and short iodine-iodine contacts of 4.19 A are formed between the layers. Optical thin-film measurements on this compound indicate a significant red shift of the exciton peak (630 nm) associated with the band gap, as compared with other SnI(4)(2)(-)-based layered perovskite structures.

All-solution processed composite hole transport layer for quantum dot light emitting diode

Energy Technology Data Exchange (ETDEWEB)

Zhang, Xiaoli [Tianjin Key Laboratory of Low Dimensional Materials Physics and Preparing Technology, School of Science, Tianjin University, Tianjin 300072 (China); Synergetic Innovation Center of Chemical Science and Engineering, Tianjin (China); Dai, Haitao, E-mail: htdai@tju.edu.cn [Tianjin Key Laboratory of Low Dimensional Materials Physics and Preparing Technology, School of Science, Tianjin University, Tianjin 300072 (China); Zhao, Junliang; Wang, Shuguo [Tianjin Key Laboratory of Low Dimensional Materials Physics and Preparing Technology, School of Science, Tianjin University, Tianjin 300072 (China); Sun, Xiaowei [Department of Electrical & Electronic Engineering, South University of Science and Technology of China, Tangchang Road 1088, Shenzhen, Guangdong 518055 (China)

2016-03-31

In the present work, poly-TPD and TCTA composite hole transport layer (HTL) was employed in solution processed CdSe/ZnS quantum dot light emitting diodes (QLEDs). As the doping level of TCTA can determine the carriers transport efficiency of HTL, the proper mixing ratio of TCTA and poly-TPD should be found to optimize the performance of composite HTL for QLEDs. The doping of poly-TPD by low TCTA content can make its HOMO level lower and then reduce the energy barrier height from HTL to quantum dots (QDs), whereas the doping of poly-TPD by the concentrated TCTA results in the degraded performance of QLEDs due to its decreased hole transport mobility. By using the optimized composition with poly-TPD:TCTA (3:1) as the hole transport layer, the luminescence of the device exhibits about double enhancement compared with that of poly-TPD based device. The improvement of luminescence is mainly attributed to the lower energy barrier of hole injection. The Förster resonant energy transfer (FRET) mechanism in the devices was investigated through theoretical and experimental analysis and the results indicate that the TCTA doping makes no difference on FRET. Therefore, the charge injection mechanism dominates the improved performance of the devices. - Highlights: • Quantum dot light emitting diodes (QLEDs) were fabricated by all solution method. • The performance of QLEDs was optimized by varying the composite hole transport layer. • The blend HTL could promote hole injection by optimizing HOMO levels. • The energy transfer mechanism was analyzed by studying Förster resonant energy transfer process.

Cube textured CeO2, BaZrO3 and LaAlO3 buffer layers on Ni based Substrates

International Nuclear Information System (INIS)

Deinhofer, C; Gritzner, G

2006-01-01

CeO 2 , BaZrO 3 as well as LaAlO 3 buffer layers were deposited on {100} Ni + 5 weight-% W substrates by a wet chemical technique. The solutions were prepared by dissolving the metal nitrates or acetates and zirconiumacetylacetonate, respectively, in mixtures of acetic acid, methanol and water. The solutions were applied by dip- or spincoating, dried at 135 deg. C and annealed at temperatures between 900 and 1 400 deg. C depending on the buffer layer for 15 min. under Ar-5% H 2 gas flow. Pole-figure measurements proved the exact texture of each buffer layer. Electron microscopy showed dense and smooth buffer layers

Dependence of magnetic properties on different buffer layers of Mn3.5Ga thin films

Science.gov (United States)

Takahashi, Y.; Sato, K.; Shima, T.; Doi, M.

2018-05-01

D022-Mn3.5Ga thin films were prepared on MgO (100) single crystalline substrates with different buffer layer (Cr, Fe, Cr/Pt and Cr/Au) using an ultra-high-vacuum electron beam vapor deposition system. From XRD patterns, a fundamental (004) peak has clearly observed for all samples. The relatively low saturation magnetization (Ms) of 178 emu/cm3, high magnetic anisotropy (Ku) of 9.1 Merg/cm3 and low surface roughness (Ra) of 0.30 nm were obtained by D022-Mn3.5Ga film (20 nm) on Cr/Pt buffer layer at Ts = 300 °C, Ta = 400 °C (3h). These findings suggest that MnGa film on Cr/Pt buffer layer is a promising PMA layer for future spin electronics devices.

Weld line optimization on thermoplastic elastomer micro injection moulded components using 3D focus variation optical microscopy

DEFF Research Database (Denmark)

Hasnaes, F.B.; Elsborg, R.; Tosello, G.

2015-01-01

The presented study investigates weld line depth development across a micro suspension ring. A focus variation microscope was used to obtain 3D images of the weld line area. Suspension rings produced with different micro injection moulding process parameters were examined to identify the correlat......The presented study investigates weld line depth development across a micro suspension ring. A focus variation microscope was used to obtain 3D images of the weld line area. Suspension rings produced with different micro injection moulding process parameters were examined to identify...

Epitaxial Growth of Hard Ferrimagnetic Mn3Ge Film on Rhodium Buffer Layer

Directory of Open Access Journals (Sweden)

Atsushi Sugihara

2015-06-01

Full Text Available Mn\\(_3\\Ge has a tetragonal Heusler-like D0\\(_{22}\\ crystal structure, exhibiting a large uniaxial magnetic anisotropy and small saturation magnetization due to its ferrimagnetic spin structure; thus, it is a hard ferrimagnet. In this report, epitaxial growth of a Mn\\(_3\\Ge film on a Rh buffer layer was investigated for comparison with that of a film on a Cr buffer layer in terms of the lattice mismatch between Mn\\(_3\\Ge and the buffer layer. The film grown on Rh had much better crystalline quality than that grown on Cr, which can be attributed to the small lattice mismatch. Epitaxial films of Mn\\(_3\\Ge on Rh show somewhat small coercivity (\\(H_{\\rm c}\\ = 12.6 kOe and a large perpendicular magnetic anisotropy (\\(K_{\\rm u}\\ = 11.6 Merg/cm\\(^3\\, comparable to that of the film grown on Cr.

Enhanced Performance of Nanowire-Based All-TiO2 Solar Cells using Subnanometer-Thick Atomic Layer Deposited ZnO Embedded Layer

International Nuclear Information System (INIS)

Ghobadi, Amir; Yavuz, Halil I.; Ulusoy, T. Gamze; Icli, K. Cagatay; Ozenbas, Macit; Okyay, Ali K.

2015-01-01

In this paper, the effect of angstrom-thick atomic layer deposited (ALD) ZnO embedded layer on photovoltaic (PV) performance of Nanowire-Based All-TiO 2 solar cells has been systematically investigated. Our results indicate that by varying the thickness of ZnO layer the efficiency of the solar cell can be significantly changed. It is shown that the efficiency has its maximum for optimal thickness of 1 ALD cycle in which this ultrathin ZnO layer improves device performance through passivation of surface traps without hampering injection efficiency of photogenerated electrons. The mechanisms contributing to this unprecedented change in PV performance of the cell have been scrutinized and discussed

Coatings with laser melt injection of ceramic particles

NARCIS (Netherlands)

de Hosson, J.T.M.; Ocelik, V.; de Oliveira, U.; Seal, S; Dahotre, NB; Moore, JJ; Suryanarayana, C; Agarwal, A

2003-01-01

The conditions for a successful Laser Melt Injection (LMI) of SiC and WC particles into the melt pool of Al8Si and Ti6Al4V alloys were studied experimentally and theoretically by FEM calculations. The laser employed is a high power Nd:YAG The formation of a relatively thick aluminium oxide layer on

Rapid and Low-cost Prototyping of Medical Devices Using 3D Printed Molds for Liquid Injection Molding

Science.gov (United States)

Chung, Philip; Heller, J. Alex; Etemadi, Mozziyar; Ottoson, Paige E.; Liu, Jonathan A.; Rand, Larry; Roy, Shuvo

2014-01-01

Biologically inert elastomers such as silicone are favorable materials for medical device fabrication, but forming and curing these elastomers using traditional liquid injection molding processes can be an expensive process due to tooling and equipment costs. As a result, it has traditionally been impractical to use liquid injection molding for low-cost, rapid prototyping applications. We have devised a method for rapid and low-cost production of liquid elastomer injection molded devices that utilizes fused deposition modeling 3D printers for mold design and a modified desiccator as an injection system. Low costs and rapid turnaround time in this technique lower the barrier to iteratively designing and prototyping complex elastomer devices. Furthermore, CAD models developed in this process can be later adapted for metal mold tooling design, enabling an easy transition to a traditional injection molding process. We have used this technique to manufacture intravaginal probes involving complex geometries, as well as overmolding over metal parts, using tools commonly available within an academic research laboratory. However, this technique can be easily adapted to create liquid injection molded devices for many other applications. PMID:24998993

Utilizing Z-track Air Lock Technique to Reduce Pain in Intramuscular Injections

Directory of Open Access Journals (Sweden)

Evelyn Hemme Tambunan

2015-04-01

Full Text Available Introduction: Injection is one of most painful and common medical interventions that more than 12 billion of it are administered annually throughout the world. Pain remains as one of the unresolved health problems. The objective of this research was to investigate the pain severity utilizing the z-track air lock technique during intra muscular injection procedure. Method:This study was conducted as an unblinded cinical trial, where 90 female subjects aged between 18-25 years old were randomly assigned to three groups of 30. Each group received z-track air lock (Group ZTAL, air lock (AL, and z-track (Group ZT techniques. Neurobion 5000 vitamin used as an injection substance.A Verbal Rating Scale (VRS on 0–3 was used to evaluate the severity of pain during procedure. Data were analized using the SPSS version 19. Groups’ age, Body Mass Index (BMI and pain severity were analyzed through descriptive and One Way ANOVA statistics. Results: Results showed that there were no signifi cant differences of pain severity both within and between groups (p > 0.05. Discussion: Both Z-track and air lock method are less pain compared to traditional method according to previous studies. Noncicepti stimulus inhibited nocicepti stimulus in z-track technique while locking effect inhibit leakeage of substance injection to subcutaneous layer of skin which contain of nerve fi bers. However All techniques are recommended to produce less pain therefore it can be considered as a standard procedure for intra muscular injection. Keywords: intramuscular injection, z-track air lock technique, pain

Deep-well injection of radioactive waste in Russia

International Nuclear Information System (INIS)

Hoek, J.

1998-01-01

In the Russian federation, deep borehole injection of liquid radioactive waste has been established practice since at least 1963. The liquid is injected into sandy or other formations with high porosity, which are isolated by water-tight layers. This technique has also been used elsewhere for toxic liquid waste and residues from mining operations. Deep-well injection of radioactive waste is not currently used in any of the European Commission (EC) countries. In this paper the results of a EC-funded study were presented. The study is entitled 'Measurements, modelling of migration and possible radiological consequences at deep well injection sites for liquid radioactive waste in Russia', COSU-CT94-0099-UK. The study was carried out jointly by AEA Technology, CAG and the Research Institute for Nuclear Reactors (NIIAR) at Dimitrovgrad. Many scientists have contributed to the results reported here. The aims of the study are: Provision of extensive information on the deep-well injection repositories and their use in the former Soviet Union; Provision of a methodology to assess safety aspects of deep-well injection of liquid radioactive waste in deep geological formations; This will allow evaluation of proposals to use deep-well injection techniques in other regions; Support for Russian regulatory bodies through evaluation of the suitability of the sites, including estimates of the maximum amount of waste that can be safely stored in them; and Provision of a methodology to assess the use of deep-well injection repositories as an alternative disposal technique for EC countries. 7 refs

Delayed Superficial Migration of Retained Hyaluronic Acid Years Following Periocular Injection.

Science.gov (United States)

Chang, Jessica R; Baharestani, Samuel; Salek, Sherveen S; Piluek, W Jordan; Eberhart, Charles G; McCulley, Timothy J

Cosmetic injection of hyaluronic acid (HA) and other fillers is increasingly common, and the late complications of these relatively new procedures are now coming to medical attention. Three patients with delayed periocular swelling that began years after injection of HA are described, with CT, MRI, and histopathologic characterization. While HA fillers are marketed as having a temporary effect of several months, the authors demonstrate that they may persist in the body for up to 9 years. Unlike most previous reports, there was no inflammatory reaction or encapsulation, simply infiltration into more superficial subcutaneous layers. All cases improved after surgical biopsy and hyaluronidase injections. Delayed periocular swelling after filler injections from several years prior can mimic serious medical conditions. With a detailed history and high index of suspicion, one may avoid a costly and invasive workup.

A new electrode design for ambipolar injection in organic semiconductors.

Science.gov (United States)

Kanagasekaran, Thangavel; Shimotani, Hidekazu; Shimizu, Ryota; Hitosugi, Taro; Tanigaki, Katsumi

2017-10-17

Organic semiconductors have attracted much attention for low-cost, flexible and human-friendly optoelectronics. However, achieving high electron-injection efficiency is difficult from air-stable electrodes and cannot be equivalent to that of holes. Here, we present a novel concept of electrode composed of a bilayer of tetratetracontane (TTC) and polycrystalline organic semiconductors (pc-OSC) covered by a metal layer. Field-effect transistors of single-crystal organic semiconductors with the new electrodes of M/pc-OSC/TTC (M: Ca or Au) show both highly efficient electron and hole injection. Contact resistance for electron injection from Au/pc-OSC/TTC and hole injection from Ca/pc-OSC/TTC are comparable to those for electron injection from Ca and hole injection from Au, respectively. Furthermore, the highest field-effect mobilities of holes (22 cm 2  V -1  s -1 ) and electrons (5.0 cm 2  V -1  s -1 ) are observed in rubrene among field-effect transistors with electrodes so far proposed by employing Ca/pc-OSC/TTC and Au/pc-OSC/TTC electrodes for electron and hole injection, respectively.One of technological challenges building organic electronics is efficient injection of electrons at metal-semiconductor interfaces compared to that of holes. The authors show an air-stable electrode design with induced gap states, which support Fermi level pinning and thus ambipolar carrier injection.

Trends in (LaMnO3)n/(SrTiO3)m superlattices with varying layer thicknesses

KAUST Repository

Jilili, J.

2015-09-01

We investigate the thickness dependence of the structural, electronic, and magnetic properties of (LaMnO3)n/(SrTiO3)m (n, m = 2, 4, 6, 8) superlattices using density functional theory. The electronic structure turns out to be highly sensitive to the onsite Coulomb interaction. In contrast to bulk SrTiO3, strongly distorted O octahedra are observed in the SrTiO3 layers with a systematic off centering of the Ti atoms. The systems favour ferromagnetic spin ordering rather than the antiferromagnetic spin ordering of bulk LaMnO3 and all show half-metallicity, while a systematic reduction of the minority spin band gaps as a function of the LaMnO3 and SrTiO3 layer thicknesses originates from modifications of the Ti dxy states.

Comparative study of diode-pumping self-injection and injection-locking Tm:YAG lasers

International Nuclear Information System (INIS)

Wu, C T; Chen, F; Ju, Y L; Wang, Y Z

2013-01-01

A comparative study of the laser characteristics of self-injection and injection-locking Tm:YAG lasers is given in this paper. At a pump energy of 145 mJ and Q-switched repetition rate of 100 Hz, an output energy of 2.39 mJ was obtained for an injection-locking Tm:YAG laser, with a pulse width of 403.2 ns and a pulse building-up time of 2.12 μs. Under the same conditions, the output energy, pulse width and pulse build-up time for a self-injection Tm:YAG laser were 2.21 mJ, 407.0 ns and 3.95 μs, respectively. The threshold of the Q-switched injection-locking Tm:YAG laser was much lower than that of the self-injection laser, and the pulse width was narrower and the pulse build-up time shorter. Additionally, the output spectrum was much purer for the injection-locking laser. (paper)

ITER Neutral Beam Injection System

International Nuclear Information System (INIS)

Ohara, Yoshihiro; Tanaka, Shigeru; Akiba, Masato

1991-03-01

A Japanese design proposal of the ITER Neutral Beam Injection System (NBS) which is consistent with the ITER common design requirements is described. The injection system is required to deliver a neutral deuterium beam of 75MW at 1.3MeV to the reactor plasma and utilized not only for plasma heating but also for current drive and current profile control. The injection system is composed of 9 modules, each of which is designed so as to inject a 1.3MeV, 10MW neutral beam. The most important point in the design is that the injection system is based on the utilization of a cesium-seeded volume negative ion source which can produce an intense negative ion beam with high current density at a low source operating pressure. The design value of the source is based on the experimental values achieved at JAERI. The utilization of the cesium-seeded volume source is essential to the design of an efficient and compact neutral beam injection system which satisfies the ITER common design requirements. The critical components to realize this design are the 1.3MeV, 17A electrostatic accelerator and the high voltage DC acceleration power supply, whose performances must be demonstrated prior to the construction of ITER NBI system. (author)

Clinicopathological Studies on Gentamicin Toxicity in White Leghorn Commercial Layers

Directory of Open Access Journals (Sweden)

Najam Ul Islam, M. Zargham Khan1, M. Kashif Saleemi*1, Ahrar Khan1, Sheraz Ahmed Bhatti1, Muhammad Yousaf2 and Zahoor-ul-Hassan3

2011-10-01

Full Text Available Gentamicin is an effective and economical drug used to control infectious diseases in poultry but is highly toxic and had slow clearance from the body. This study aimed to report three cases of gentamicin toxicity in three White Leghorn (WLH layer flocks in different poultry producing areas of Pakistan. In first case, gentamicin was injected in a 9000 WLH layer flock @ 10 mg/kg body weight (BW for seven times during 9-15 weeks for age. In second case, gentamicin was injected in a flock of 7500 WLH layers @ 25 mg/kg BW for four times during 17-18 weeks of age. In third case, gentamicin was injected in flock of 16000 WLH layers @ 22.22 mg/kg BW three times in 20-21 weeks of age. Flock wise mortality was 8.69, 82.63 and 71.86%, respectively. Birds were dehydrated, emaciated and had prominent keel bone. Clinical signs included dehydration, decreased body weight leading to emaciation, decreased feed intake, increased water intake and watery diarrhea. Necropsy revealed prominent keal bone, shrunken muscles swollen kidneys bulging out from bony sockets. Petechial and echymotic hemorrhages were present on heart and skeletal muscles. Liver was enlarged with hemorrhagic streaks on its surface. Microscopically, hemorrhages and acute tubular necrosis was recorded in kidneys. Liver had hemorrhages, cellular infiltration and vacuolar (fatty degeneration of hepatocytes. From the results, it could be concluded that overdosing and repeated administration of gentamicin was highly toxic to birds.

Effect of oxide insertion layer on resistance switching properties of copper phthalocyanine

Science.gov (United States)

Joshi, Nikhil G.; Pandya, Nirav C.; Joshi, U. S.

2013-02-01

Organic memory device showing resistance switching properties is a next-generation of the electrical memory unit. We have investigated the bistable resistance switching in current-voltage (I-V) characteristics of organic diode based on copper phthalocyanine (CuPc) film sandwiched between aluminum (Al) electrodes. Pronounced hysteresis in the I-V curves revealed a resistance switching with on-off ratio of the order of 85%. In order to control the charge injection in the CuPc, nanoscale indium oxide buffer layer was inserted to form Al/CuPc/In2O3/Al device. Analysis of I-V measurements revealed space charge limited switching conduction at the Al/CuPc interface. The traps in the organic layer and charge blocking by oxide insertion layer have been used to explain the absence of resistance switching in the oxide buffer layered memory device cell. Present study offer potential applications for CuPc organic semiconductor in low power non volatile resistive switching memory and logic circuits.

Effect of Nonionic Surfactant Additive in PEDOT:PSS on PFO Emission Layer in Organic-Inorganic Hybrid Light-Emitting Diode.

Science.gov (United States)

Cho, Seong Rae; Porte, Yoann; Kim, Yun Cheol; Myoung, Jae-Min

2018-03-21

Poly(9,9-dioctylfluorene) (PFO) has attracted significant interests owing to its versatility in electronic devices. However, changes in its optical properties caused by its various phases and the formation of oxidation defects limit the application of PFO in light-emitting diodes (LEDs). We investigated the effects of the addition of Triton X-100 (hereinafter shortened as TX) in poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) to induce interlayer diffusion between PEDOT:PSS and PFO to enhance the stability of the PFO phase and suppress its oxidation. Photoluminescence (PL) measurement on PFO/TX-mixed PEDOT:PSS layers revealed that, upon increasing the concentration of TX in the PEDOT:PSS layer, the β phase of PFO could be suppressed in favor of the glassy phase and the wide PL emission centered at 535 nm caused by ketone defects formed by oxidation was decreased considerably. LEDs were then fabricated using PFO as an emission layer, TX-mixed PEDOT:PSS as hole-transport layer, and zinc oxide (ZnO) nanorods as electron-transport layer. As the TX concentration reached 3 wt %, the devices exhibited dramatic increases in current densities, which were attributed to the enhanced hole injection due to TX addition, along with a shift in the dominant emission wavelength from a green electroluminescence (EL) emission centered at 518 nm to a blue EL emission centered at 448 nm. The addition of TX in PEDOT:PSS induced a better hole injection in the PFO layer, and through interlayer diffusion, stabilized the glassy phase of PFO and limited the formation of oxidation defects.

Synthesis, crystal structure and optical properties of two new layered cadmium iodates: Cd(IO3)X (X=Cl, OH)

International Nuclear Information System (INIS)

Yang, Bing-Ping; Mao, Jiang-Gao

2014-01-01

Systematic explorations of new compounds in the cadmium iodate system by hydrothermal reactions led to two layered iodates, namely, Cd(IO 3 )X (X=Cl, OH). Cd(IO 3 )Cl crystallizes in the orthorhombic space group Cmca (No. 64) whereas Cd(IO 3 )(OH) crystallizes in the orthorhombic space group Pnma (No. 62). Cd(IO 3 )Cl displays a unique double layered structure composed of 1 ∞ [Cd−O 3 Cl] n chains. Cadmium octahedrons form a 1D chain along the a-axis through edge sharing, and such chains are further interconnected via IO 3 groups to form a special double layer on (020) plane. Cd(IO 3 )(OH) also exhibits a layered structure that is composed of cadmium cations, IO 3 groups and hydroxyl ions. Within a layer, chains of CdO 6 edge-shared octahedra are observed along the b-axis. And these chains are connected by IO 3 groups into a layer parallel to the bc plane. Spectroscopic characterizations, elemental analysis, and thermogravimetric analysis for the reported two compounds are also presented. - Graphical abstract: Two new layered cadmium iodates Cd(IO 3 )X (X=Cl, OH) are reported. Cd(IO 3 )Cl features a unique double layered structure whereas Cd(IO 3 )(OH) displays an ordinary layered structure. - Highlights: • Two new layered cadmium iodates Cd(IO 3 )X (X=Cl, OH) are reported. • Cd(IO 3 )Cl features a unique double layered structure. • Cd(IO 3 )(OH) displays an ordinary layered structure. • The spectroscopic and thermal properties have been studied in detail

Selective UV–O3 treatment for indium zinc oxide thin film transistors with solution-based multiple active layer

Science.gov (United States)

Kim, Yu-Jung; Jeong, Jun-Kyo; Park, Jung-Hyun; Jeong, Byung-Jun; Lee, Hi-Deok; Lee, Ga-Won

2018-06-01

In this study, a method to control the electrical performance of solution-based indium zinc oxide (IZO) thin film transistors (TFTs) is proposed by ultraviolet–ozone (UV–O3) treatment on the selective layer during multiple IZO active layer depositions. The IZO film is composed of triple layers formed by spin coating and UV–O3 treatment only on the first layer or last layer. The IZO films are compared by X-ray photoelectron spectroscopy, and the results show that the atomic ratio of oxygen vacancy (VO) increases in the UV–O3 treatment on the first layer, while it decreases on last layer. The device characteristics of the bottom gated structure are also improved in the UV–O3 treatment on the first layer. This indicates that the selective UV–O3 treatment in a multi-stacking active layer is an effective method to optimize TFT properties by controlling the amount of VO in the IZO interface and surface independently.

Improvement of photoluminescence from Ge layer with patterned Si{sub 3}N{sub 4} stressors

Energy Technology Data Exchange (ETDEWEB)

Oda, Katsuya, E-mail: Katsuya.Oda.cb@hitachi.com; Okumura, Tadashi; Tani, Kazuki; Saito, Shin-ichi; Ido, Tatemi

2014-04-30

Lattice strain applied by patterned Si{sub 3}N{sub 4} stressors in order to improve the optical properties of Ge layers directly grown on a Si substrate was investigated. Patterned Si{sub 3}N{sub 4} stressors were fabricated by various methods and their effects on the strain and photoluminescence were studied. Although we found that when the stressor was fabricated by thermal chemical vapor deposition (CVD), the Ge waveguide was tensilely and compressively strained in the edge and center positions, respectively, and photoluminescence (PL) could be improved by decreasing the width of the waveguide, the crystallinity of the Ge waveguide was degraded by the thermal impact of the deposition process. Low-temperature methods were therefore used to make the patterned stressors. The tensile strain of the Ge layer increased from 0.14% to 0.2% when the stressor was grown by plasma enhanced CVD at 350 °C, but the effects of the increased tensile strain could not be confirmed because the Si{sub 3}N{sub 4} layer was unstable when irradiated with the excitation light used in photoluminescence measurements. Si{sub 3}N{sub 4} stressors grown by inductively coupled plasma CVD at room temperature increased the tensile strain of the Ge layer up to 0.4%, thus red-shifting the PL peak and obviously increasing the PL intensity. These results indicate that the Si{sub 3}N{sub 4} stressors fabricated by the room-temperature process efficiently improve the performance of Ge light-emitting devices. - Highlights: • Ge layers were directly grown on a Si substrate by low-temperature epitaxial growth. • Si{sub 3}N{sub 4} stressors were fabricated on the Ge layers by various methods. • Tensile strain of the Ge layers was improved by the Si{sub 3}N{sub 4} stressors. • Photoluminescence (PL) intensity was increased with the Si{sub 3}N{sub 4} stressors. • Red-shift of the PL spectra was observed from the tensile strained Ge layers.

Modelling and Simulation of Structural Deformation of Isothermal Subsurface Flow and Carbon Dioxide Injection

KAUST Repository

El-Amin, Mohamed

2011-05-15

Injection of CO2 in hydrocarbon reservoir has double benefit. On the one hand, it is a profitable method due to issues related to global warming, and on the other hand it is an effective mechanism to enhance hydrocarbon recovery. Such injection associates complex processes involving, e.g., solute transport of dissolved materials, in addition to local changes in density of the phases. Also, increasing carbon dioxide injection may cause a structural deformation of the medium, so it is important to include such effect into the model. The structural deformation modelling in carbon sequestration is important to evaluate the medium stability to avoid CO2 leakage to the atmosphere. On the other hand, geologic formation of the medium is usually heterogeneous and consists of several layers of different permeability. In this work we conduct numerical simulation of two-phase flow in a heterogeneous porous medium domain with dissolved solute transport as well as structural deformation effects. The solute transport of the dissolved component is described by concentration equation. The structural deformation for geomechanics is derived from a general local differential balance equation with neglecting the local mass balance of solid phase and the inertial force term. The flux continuity condition is used at interfaces between different permeability layers of the heterogeneous medium. We analyze the vertical migration of a CO2 plume injected into a 2D layered reservoir. Analysis of distribution of flow field components such as saturation, pressures, velocities, and CO2 concentration are presented.

Tungsten oxides as interfacial layers for improved performance in hybrid optoelectronic devices

International Nuclear Information System (INIS)

Vasilopoulou, M.; Palilis, L.C.; Georgiadou, D.G.; Argitis, P.; Kennou, S.; Kostis, I.; Papadimitropoulos, G.; Stathopoulos, N.A.; Iliadis, A.A.; Konofaos, N.; Davazoglou, D.; Sygellou, L.

2011-01-01

Tungsten oxide (WO 3 ) films with thicknesses ranging from 30 to 100 nm were grown by Hot Filament Vapor Deposition (HFVD). Films were studied by X-Ray Photoemission Spectroscopy (XPS) and were found to be stoichiometric. The surface morphology of the films was characterized by Atomic Force Microscopy (AFM). Samples had a granular form with grains in the order of 100 nm. The surface roughness was found to increase with film thickness. HFVD WO 3 films were used as conducting interfacial layers in advanced hybrid organic-inorganic optoelectronic devices. Hybrid-Organic Light Emitting Diodes (Hy-OLEDs) and Organic Photovoltaics (Hy-OPVs) were fabricated with these films as anode and/or as cathode interfacial conducting layers. The Hy-OLEDs showed significantly higher current density and a lower turn-on voltage when a thin WO 3 layer was inserted at the anode/polymer interface, while when inserted at the cathode/polymer interface the device performance was found to deteriorate. The improvement was attributed to a more efficient hole injection and transport from the Fermi level of the anode to the Highest Occupied Molecular Orbital (HOMO) of a yellow emitting copolymer (YEP). On the other hand, the insertion of a thin WO 3 layer at the cathode/polymer interface of Hy-OPV devices based on a polythiophene-fullerene bulk-heterojunction blend photoactive layer resulted in an increase of the produced photogenerated current, more likely due to improved electron extraction at the Al cathode.

Preparation of Chitosan-based Injectable Hydrogels and Its Application in 3D Cell Culture.

Science.gov (United States)

Li, Yongsan; Zhang, Yaling; Wei, Yen; Tao, Lei

2017-09-29

The protocol presents a facile, efficient, and versatile method to prepare chitosan-based hydrogels using dynamic imine chemistry. The hydrogel is prepared by mixing solutions of glycol chitosan with a synthesized benzaldehyde terminated polymer gelator, and hydrogels are efficiently obtained in several minutes at room temperature. By varying ratios between glycol chitosan, polymer gelator, and water contents, versatile hydrogels with different gelation times and stiffness are obtained. When damaged, the hydrogel can recover its appearances and modulus, due to the reversibility of the dynamic imine bonds as crosslinkages. This self-healable property enables the hydrogel to be injectable since it can be self-healed from squeezed pieces to an integral bulk hydrogel after the injection process. The hydrogel is also multi-responsive to many bio-active stimuli due to different equilibration statuses of the dynamic imine bonds. This hydrogel was confirmed as bio-compatible, and L929 mouse fibroblast cells were embedded following standard procedures and the cell proliferation was easily assessed by a 3D cell cultivation process. The hydrogel can offer an adjustable platform for different research where a physiological mimic of a 3D environment for cells is profited. Along with its multi-responsive, self-healable, and injectable properties, the hydrogels can potentially be applied as multiple carriers for drugs and cells in future bio-medical applications.

Evaluation of performance, safety, subject acceptance, and compliance of a disposable autoinjector for subcutaneous injections in healthy volunteers

Directory of Open Access Journals (Sweden)

Cecile Berteau

2010-09-01

Full Text Available Cecile Berteau1, Florence Schwarzenbach1, Yves Donazzolo2, Mathilde Latreille2, Julie Berube3, Herve Abry1, Joël Cotten1, Celine Feger1, Philippe E Laurent11BD Medical Pharmaceutical Systems, Le-Pont-de-Claix, 2Eurofins Optimed Clinical Research, Gières, France; 3Statistics, BD Corporate, Franklin Lakes, NJ, USAObjective: A disposable autoinjector was developed for subcutaneous (SC self-injection by patients with chronic diseases. To verify its performance and evaluate its acceptance, a clinical study was conducted in healthy volunteers, comparing SC injections performed by subjects using the autoinjector with SC injections performed by nurses using a syringe.Methods: This was a randomized, single-center, crossover study comparing SC self-injection using an autoinjector with SC nurse-administered injection using a syringe. Two volumes (0.2 mL and 1 mL were injected into healthy volunteers. Study objectives included assessment of the accuracy and consistency of the volume injected by the injection systems, and skin reaction and pain associated with the injection. The fluid depot in the SC tissue layer was evaluated by ultrasound. Subject acceptance was evaluated using questionnaires on attitudes and emotions towards the injection technique, and challenged by seeking the subjects’ preferred system for a final study injection or future treatment.Results: A total of 960 injections (480 with autoinjector, 480 with syringe were performed in 40 subjects. There were no significant differences in mean fluid leakage and injected volumes between the systems. Pain associated with the injection was significantly lower with the autoinjector than with the syringe. Local skin reaction at the injection site was overall satisfactory. Injections were appropriately performed by all subjects. At study end, all 40 subjects preferred the autoinjector for a final study injection and for future treatment.Conclusion: This study indicated that the autoinjector used by

Effect of pegaptanib sodium 0.3 mg intravitreal injections (Macugen) in intraocular pressure

DEFF Research Database (Denmark)

Boyer, David S; Goldbaum, Mauro; Leys, Anita M

2014-01-01

OBJECTIVE: To assess the rate of pegaptanib-associated sustained intraocular pressure (IOP) elevation. METHODS: A posthoc analysis was conducted on all IOP measurements, except the immediate 30-min postinjection, from all subjects randomised to pegaptanib 0.3 mg or sham injections continuously in...

Plasma and milk concentrations of vitamin D3 and 25-hydroxy vitamin D3 following intravenous injection of vitamin D3 or 25-hydroxy vitamin D3.

OpenAIRE

Hidiroglou, M; Knipfel, J E

1984-01-01

Plasma levels of vitamin D3 or 25-hydroxyvitamin D3 in ewes after administration of a single massive intravenous dose of vitamin D3 (2 X 10(6) IU) or 25-hydroxy vitamin D3 (5 mg) were determined at zero, one, two, three, five, ten and 20 days postinjection. In six ewes injected with vitamin D3 conversion of vitamin D3 to 25-hydroxy vitamin D3 resulted in a six-fold increase in the plasma 25-hydroxy vitamin D3 level within one day. Elevated levels were maintained until day 10 but by day 20 a s...

Molecular characterization and expression profiling of BMP 3 gene in broiler and layer chicken.

Science.gov (United States)

Divya, Devara; Bhattacharya, Tarun Kumar; Gnana Prakash, Manthani; Chatterjee, R N; Shukla, Renu; Guru Vishnu, Pothana Boyina; Vinoth, Amirthalingam; Dushyanth, Kotha

2018-04-10

A study was carried out to characterize and explore the expression profile of BMP 3 gene in control broiler and control layer chicken. The total open reading frame of BMP 3 (1389 bp) was cloned and sequenced. The control broiler and control layer chicken showed variation at nucleotide and amino acid level with reference gene (Gallus gallus, NCBI Acc. No. NM_001034819). When compared to reference gene, the control broiler showed four nucleotide differences (c.192A>G, c.519C>T, 903G>A and 960C>G), while, control layer showed variation at c.33G>C, 192A>G, 858G>A, 904G>A, 960C>G and 1257C>T making six differences in total. However, between control broiler and control layer lines, nucleotide differences was observed at c.33G>C, 519T>C, 858G>A, 903A>G, 904G>A and 1257C>T. The change at amino acid level between reference and control broiler was p.D320N and with control layer chicken, it was p.D302N and p.D320N. On the other hand, a single amino acid difference (p.D302N) was observed between the control broiler and control layer chicken lines. The phylogenetic study displayed a close relationship between broiler and layer lines and reference gene and also with other avian species resulting in a cluster formation. These cluster in turn displayed a distant link with the mammalian species. The expression profile of BMP 3 gene exhibited a variation at different stages of embryonic development and also at post embryonic period among the lines with control layer showing higher expression than that of broiler chicken. The protein was also detected in bone marrow tissue of broiler and layer lines by western blotting. It is concluded that the BMP 3 gene sequence differed at nucleotide and amino acid level among the lines and the gene expressed differentially at different periods of embryonic development and also at post hatch period.

Effect of Post-annealing on the Electrochromic Properties of Layer-by-Layer Arrangement FTO-WO3-Ag-WO3-Ag

Science.gov (United States)

Hoseinzadeh, S.; Ghasemiasl, R.; Bahari, A.; Ramezani, A. H.

2018-03-01

In the current study, composites of tungsten trioxide (W03) and silver (Ag) are deposited in a layer-by-layer electrochromic (EC) arrangement onto a fluorine-doped tin oxide coated glass substrate. Tungsten oxide nanoparticles are an n-type semiconductor that can be used as EC cathode material. Nano-sized silver is a metal that can serve as an electron trap center that facilitates charge departure. In this method, the WO3 and Ag nanoparticle powder were deposited by physical vapor deposition onto the glass substrate. The fabricated electrochromic devices (ECD) were post-annealed to examine the effect of temperature on their EC properties. The morphology of the thin film was characterized by scanning electron microscopy and atomic force microscopy. Structural analysis showed that the addition of silver dopant increased the size of the aggregation of the film. The film had an average approximate roughness of about 17.8 nm. The electro-optical properties of the thin film were investigated using cyclic voltammetry and UV-visible spectroscopy to compare the effects of different post-annealing temperatures. The ECD showed that annealing at 200°C provided better conductivity (maximum current of about 90 mA in the oxidation state) and change of transmittance (ΔT = 90% at the continuous switching step) than did the other thin films. The optical band gaps of the thin film showed that it allowed direct transition at 3.85 eV. The EC properties of these combinations of coloration efficiency and response time indicate that the WO3-Ag-WO3-Ag arrangement is a promising candidate for use in such ECDs.

Atomic-Layer-Deposited Transparent Electrodes for Silicon Heterojunction Solar Cells

International Nuclear Information System (INIS)

Demaurex, Benedicte; Seif, Johannes P.; Smit, Sjoerd; Macco, Bart; Kessels, W. M.; Geissbuhler, Jonas; De Wolf, Stefaan; Ballif, Christophe

2014-01-01

We examine damage-free transparent-electrode deposition to fabricate high-efficiency amorphous silicon/crystalline silicon heterojunction solar cells. Such solar cells usually feature sputtered transparent electrodes, the deposition of which may damage the layers underneath. Using atomic layer deposition, we insert thin protective films between the amorphous silicon layers and sputtered contacts and investigate their effect on device operation. We find that a 20-nm-thick protective layer suffices to preserve, unchanged, the amorphous silicon layers beneath. Insertion of such protective atomic-layer-deposited layers yields slightly higher internal voltages at low carrier injection levels. However, we identify the presence of a silicon oxide layer, formed during processing, between the amorphous silicon and the atomic-layer-deposited transparent electrode that acts as a barrier, impeding hole and electron collection

Diffusion of drag-reducing polymer solutions within a rough-walled turbulent boundary layer

Science.gov (United States)

Elbing, Brian R.; Dowling, David R.; Perlin, Marc; Ceccio, Steven L.

2010-04-01

The influence of surface roughness on diffusion of wall-injected, drag-reducing polymer solutions within a turbulent boundary layer was studied with a 0.94 m long flat-plate test model at speeds of up to 10.6 m s-1 and Reynolds numbers of up to 9×106. The surface was hydraulically smooth, transitionally rough, or fully rough. Mean concentration profiles were acquired with planar laser induced fluorescence, which was the primary flow diagnostic. Polymer concentration profiles with high injection concentrations (≥1000 wppm) had the peak concentration shifted away from the wall, which was partially attributed to a lifting phenomenon. The diffusion process was divided into three zones—initial, intermediate, and final. Studies of polymer injection into a polymer ocean at concentrations sufficient for maximum drag reduction indicated that the maximum initial zone length is of the order of 100 boundary layer thicknesses. The intermediate zone results indicate that friction velocity and roughness height are important scaling parameters in addition to flow and injection conditions. Lastly, the current results were combined with those in Petrie et al. ["Polymer drag reduction with surface roughness in flat-plate turbulent boundary layer flow," Exp. Fluids 35, 8 (2003)] to demonstrate that the influence of polymer degradation increases with increased surface roughness.

Effect of different conductivity between the spin polarons on spin injection in a ferromagnet/organic semiconductor system

International Nuclear Information System (INIS)

Mi Yilin; Zhang Ming; Yan Hui

2008-01-01

Spin injection across ferromagnet/organic semiconductor system with finite width of the layers was studied theoretically considering spin-dependent conductivity in the organic-semiconductor. It was found that the spin injection efficiency is directly dependent on the difference between the conductivity of the up-spin and down-spin polarons in the spin-injected organic system. Furthermore, the finite width of the structure, interfacial electrochemical-potential and conductivity mismatch have great influence on the spin injection process across ferromagnet/organic semiconductor interface

Growth and microstructure of iron nitride layers and pore formation in {epsilon}-Fe{sub 3}N

Energy Technology Data Exchange (ETDEWEB)

Middendorf, C.; Mader, W. [Univ. Bonn, Inst. fuer Anorganische Chemie, Bonn (Germany)

2003-03-01

Layers of {epsilon}-Fe{sub 3}N and {gamma}'-Fe{sub 4}N on ferrite were produced by nitriding iron single crystals or rolled sheets of iron in flowing ammonia at 520 C. The nitride layers were characterised using X-ray diffraction, light microscopy as well as scanning and transmission electron microscopy. The compound layer consists of {epsilon}-Fe{sub 3}N at the surface and of {gamma}'-Fe{sub 4}N facing the ferrite. After 4 h of nitriding, pores develop in the near surface region of {epsilon}-Fe{sub 3}N showing more or less open porosity. Growth of the entire compound layer as well as of the massive and the porous {epsilon}-Fe{sub 3}N sublayer is diffusion-controlled and follows a parabolic growth rate. The {gamma}'-Fe{sub 4}N layer is formed as a transition phase within a narrow interval of nitrogen activity, and it shows little growth in thickness. The transformation of {gamma}'-Fe{sub 4}N to {epsilon}-Fe{sub 3}N is topotactic, where the orientation of the closed-packed iron layers of the crystal structures is preserved. Determination of lattice plane spacings was possible by X-ray diffraction, and this was correlated to the nitrogen content of {epsilon}-Fe{sub 3}N. While the porous layer exhibits an enhanced nitrogen content corresponding to the chemical composition Fe{sub 3}N{sub 1.1}, the massive e Fe{sub 3}N layer corresponds to Fe{sub 3}N{sub 1.0}. The pore formation in {epsilon}-Fe{sub 3}N{sub 1.1} is concluded to be the result of excess nitrogen atoms on non-structural sites, which have a high mobility. Therefore, recombination of excess nitrogen to molecular N{sub 2} at lattice defects is preferred in {epsilon}-Fe{sub 3}N with high nitrogen content compared to stoichiometric {epsilon}-Fe{sub 3}N{sub 1.0} with nitrogen on only structural sites. (orig.)

Experiment HFR-B1: A preliminary analysis of the water-vapor injection experiments in capsule 3

International Nuclear Information System (INIS)

Myers, B.F.

1993-01-01

A preliminary analysis of the response of uranium oxycarbide (UCO) fuel to water vapor addition in capsule 3 of experiment HFR-B1 (HFR-B1/3) has been conducted. The analysis provides an early indication of the behavior of fission gas release under a wider range of water-vapor pressures and of temperatures than heretofore studied. A preliminary analysis of selected aspects of the water-vapor injection tests in capsule 3 of experiment HFR-B1 is presented. The release of fission gas stored in bubbles and the diffusive release of fission-gas atoms are distinguished. The dependence of the release of stored fission gas ( 85m Kr) on water-vapor pressure, P(H 2 O), and temperature were established taking into account the contributing mechanisms of gaseous release, the effect of graphite hydrolysis, and the requirement of consistency with experiment HRB-17 in which similar water-vapor injection tests were conducted. The dependence on P(H 2 O) becomes weaker as temperatures increase above 770 degree C; the activation energy for release of stored-fission gas is 393 kJ/mol. Isorelease curves for the pressure-temperature plane were deduced from a derived functional relation. The stored-fission gas releases as a function of P(H 2 O) at a common temperature for experiments HFR-B1 and HRB-17 differ by a factor of 4; this discrepancy could be attributed to the differences in fission-rate density and neutron flux between the two experiments. Diffusive release of fission gas occurred during and after the release of stored gas. The ratio of diffusive release during water-vapor injection to that prior to injection varied in contrast to the results from HRB-17. The variation was attributed to the practice of injecting water vapor into HFR-B1 before sintering of the fuel, hydrolyzed in the previous test, was completed. The derived activation energy for diffusive release is 23.6 kJ/mol

Experiment HFR-B1: A preliminary analysis of the water-vapor injection experiments in capsule 3

Energy Technology Data Exchange (ETDEWEB)

Myers, B.F.

1993-08-01

A preliminary analysis of the response of uranium oxycarbide (UCO) fuel to water vapor addition in capsule 3 of experiment HFR-B1 (HFR-B1/3) has been conducted. The analysis provides an early indication of the behavior of fission gas release under a wider range of water-vapor pressures and of temperatures than heretofore studied. A preliminary analysis of selected aspects of the water-vapor injection tests in capsule 3 of experiment HFR-B1 is presented. The release of fission gas stored in bubbles and the diffusive release of fission-gas atoms are distinguished. The dependence of the release of stored fission gas ({sup 85m}Kr) on water-vapor pressure, P(H{sub 2}O), and temperature were established taking into account the contributing mechanisms of gaseous release, the effect of graphite hydrolysis, and the requirement of consistency with experiment HRB-17 in which similar water-vapor injection tests were conducted. The dependence on P(H{sub 2}O) becomes weaker as temperatures increase above 770{degree}C; the activation energy for release of stored-fission gas is 393 kJ/mol. Isorelease curves for the pressure-temperature plane were deduced from a derived functional relation. The stored-fission gas releases as a function of P(H{sub 2}O) at a common temperature for experiments HFR-B1 and HRB-17 differ by a factor of 4; this discrepancy could be attributed to the differences in fission-rate density and neutron flux between the two experiments. Diffusive release of fission gas occurred during and after the release of stored gas. The ratio of diffusive release during water-vapor injection to that prior to injection varied in contrast to the results from HRB-17. The variation was attributed to the practice of injecting water vapor into HFR-B1 before sintering of the fuel, hydrolyzed in the previous test, was completed. The derived activation energy for diffusive release is 23.6 kJ/mol.

Effect of double layer thickness on magnetoelectric coupling in multiferroic BaTiO3-Bi0.95Gd0.05FeO3 multilayers

Science.gov (United States)

Hohenberger, S.; Lazenka, V.; Temst, K.; Selle, S.; Patzig, C.; Höche, T.; Grundmann, M.; Lorenz, M.

2018-05-01

The effect of double-layer thickness and partial substitution of Bi3+ by Gd3+ is demonstrated for multiferroic BaTiO3–BiFeO3 2–2 heterostructures. Multilayers of 15 double layers of BaTiO3 and Bi0.95Gd0.05FeO3 were deposited onto (0 0 1) oriented SrTiO3 substrates by pulsed laser deposition with various double layer thicknesses. X-ray diffraction and high resolution transmission electron microscopy investigations revealed a systematic strain tuning with layer thickness via coherently strained interfaces. The multilayers show increasingly enhanced magnetoelectric coupling with reduced double layer thickness. The maximum magnetoelectric coupling coefficient was measured to be as high as 50.8 V cm‑1 Oe‑1 in 0 T DC bias magnetic field at room temperature, and 54.9 V cm‑1 Oe‑1 above 3 T for the sample with the thinnest double layer thickness of 22.5 nm. This enhancement is accompanied by progressively increasing perpendicular magnetic anisotropy and compressive out-of-plane strain. To understand the origin of the enhanced magnetoelectric coupling in such multilayers, the temperature and magnetic field dependency of is discussed. The magnetoelectric performance of the Gd3+ substituted samples is found to be slightly enhanced when compared to unsubstituted BaTiO3–BiFeO3 multilayers of comparable double-layer thickness.

Treatment of lumbar disc herniation by using percutaneous intradiscal and paraspinal space injection of O2-O3 mixture

International Nuclear Information System (INIS)

He Xiaofeng; Yu Zhijian; Li Yanhao; Zeng Qingle; Chen Yong; Lu Wei; Kong Weidong; Xu Xiaoli; Teng Gaojun; Li Long; Peng Jing

2003-01-01

Objective: To evaluate the therapeutic effect and safety for the treatment of lumbar disc herniation by using intradiscal and paraspinal space injection of O 2 -O 3 mixture. Methods: One hundred and twenty-nine patients were selected in this study. All patients presented the symptoms of sciatica and low back pain. The diagnosis of the lumbar disc herniation including 47 bulging, 78 protrusion, and 4 extrusion was verified by CT or MR imaging. One hundred and eighty-nine herniated discs were chosen as therapeutic targets. O 2 -O 3 mixture at 40 μg/ml and 19-21G puncture needles were prepared. The injection was conducted through the puncture of intradiscal and paraspinal space. For each herniated disc treatment, 5 ml O 2 -O 3 mixture were injected into the intradiscal space and 10-15 ml into paraspinal space. Results: The patients were followed up from 3 to 18 months after treatment. The therapeutic effect showed that 79 patients (61.2%) had excellent recovery, 19 cases (14.7%) had significant relief of symptoms, and 31 patients (24.0%) got failure in treatment. No serious complication occurred. Conclusion: The therapeutic method of O 2 -O 3 mixture injection into the lumbar intradiscal and paraspinal space was a safe and effective method for the treatment of the lumbar disc herniation

Porous silicon formation by hole injection from a back side p+/n junction for electrical insulation applications

International Nuclear Information System (INIS)

Fèvre, A; Menard, S; Defforge, T; Gautier, G

2016-01-01

In this paper, we propose to study the formation of porous silicon (PS) in low doped (1 × 10 14 cm −3 ) n-type silicon through hole injection from a back side p + /n junction in the dark. This technique is investigated within the framework of electrical insulation. Three different types of junctions are investigated. The first one is an epitaxial n-type layer grown on p + doped silicon wafer. The two other junctions are carried out by boron diffusion leading to p + regions with junction depths of 20 and 115 μm. The resulting PS morphology is a double layer with a nucleation layer (NL) and macropores fully filled with mesoporous material. This result is unusual for low doped n-type silicon. Morphology variations are described depending on the junction formation process, the electrolyte composition, the anodization current density and duration. In order to validate the more interesting industrial potentialities of the p + /n injection technique, a comparison is achieved with back side illumination in terms of resulting morphology and experiments confirm comparable results. Electrical characterizations of the double layer, including NL and fully filled macropores, are then performed. To our knowledge, this is the first electrical investigation in low doped n type silicon with this morphology. Compared to the bulk silicon, the measured electrical resistivities are 6–7 orders of magnitude higher at 373 K. (paper)

Al2O3 dielectric layers on H-terminated diamond: Controlling surface conductivity

Science.gov (United States)

Yang, Yu; Koeck, Franz A.; Dutta, Maitreya; Wang, Xingye; Chowdhury, Srabanti; Nemanich, Robert J.

2017-10-01

This study investigates how the surface conductivity of H-terminated diamond can be preserved and stabilized by using a dielectric layer with an in situ post-deposition treatment. Thin layers of Al2O3 were grown by plasma enhanced atomic layer deposition (PEALD) on H-terminated undoped diamond (100) surfaces. The changes of the hole accumulation layer were monitored by correlating the binding energy of the diamond C 1s core level with electrical measurements. The initial PEALD of 1 nm Al2O3 resulted in an increase of the C 1s core level binding energy consistent with a reduction of the surface hole accumulation and a reduction of the surface conductivity. A hydrogen plasma step restored the C 1s binding energy to the value of the conductive surface, and the resistance of the diamond surface was found to be within the range for surface transfer doping. Further, the PEALD growth did not appear to degrade the surface conductive layer according to the position of the C 1s core level and electrical measurements. This work provides insight into the approaches to establish and control the two-dimensional hole-accumulation layer of the H-terminated diamond and improve the stability and performance of H-terminated diamond electronic devices.

Thermoelectric Response in Single Quintuple Layer Bi2Te3

KAUST Repository

Sharma, S.; Schwingenschlö gl, Udo

2016-01-01

of single quintuple layer Bi2Te3 by considering both the electron and phonon transport. On the basis of first-principles density functional theory, the electronic and phononic contributions are calculated by solving Boltzmann transport equations

Swelling, Functionalization, and Structural Changes of the Nanoporous Layered Silicates AMH-3 and MCM-22

KAUST Repository

Kim, Wun-gwi

2011-06-21

Nanoporous layered silicate materials contain 2D-planar sheets of nanoscopic thickness and ordered porous structure. In comparison to porous 3D-framework materials such as zeolites, they have advantages such as significantly increased surface area and decreased diffusion limitations because the layers can potentially be exfoliated or intercalated into polymers to form nanocomposite materials. These properties are particularly interesting for applications as materials for enhancing molecular selectivity and throughput in composite membranes. In this report, the swelling and surface modification chemistry of two attractive nanoporous layered silicate materials, AMH-3 and MCM-22, were studied. We first describe a method, using long-chain diamines instead of monoamines, for swelling of AMH-3 while preserving its pore structure to a greater extent during the swelling process. Then, we describe a stepwise functionalization method for functionalizing the layer surfaces of AMH-3 and MCM-22 via silane condensation reactions. The covalently attached hydrocarbon chain molecules increased the hydrophobicity of AMH-3 and MCM-22 layer surfaces and therefore allow the possibility of effectively dispersing these materials in polymer matrices for thin film/membrane applications. © 2011 American Chemical Society.

Probability theory for 3-layer remote sensing in ideal gas law environment.

Science.gov (United States)

Ben-David, Avishai; Davidson, Charles E

2013-08-26

We extend the probability model for 3-layer radiative transfer [Opt. Express 20, 10004 (2012)] to ideal gas conditions where a correlation exists between transmission and temperature of each of the 3 layers. The effect on the probability density function for the at-sensor radiances is surprisingly small, and thus the added complexity of addressing the correlation can be avoided. The small overall effect is due to (a) small perturbations by the correlation on variance population parameters and (b) cancellation of perturbation terms that appear with opposite signs in the model moment expressions.

Improved contrast polymer light-emitting diode with optical interference layers

International Nuclear Information System (INIS)

Liu, H.Y.; Sun, R.G.; Yang, K.X.; Peng, J.B.; Cao, Y.; Joo, S.K.

2007-01-01

An improved contrast polymer light diode based on the destructive optical interference layers deposited between the glass substrate and ITO anode is fabricated. It is unnecessary to be considered that the additional optical interference structure will impede carrier injection from the electrode to the carrier-transporting layer. Due to the quarter-wavelength thickness of medial ITO layer, the reflected light from first Cr layer is inverted 180 o out of phase with the reflected light from second Cr layer, resulting in the destructive interference. It is evident that the contrast ratio of the device with the optical interference structure is about three times higher than that of the conventional device

A simple method for fabricating multi-layer PDMS structures for 3D microfluidic chips

KAUST Repository

Zhang, Mengying

2010-01-01

We report a simple methodology to fabricate PDMS multi-layer microfluidic chips. A PDMS slab was surface-treated by trichloro (1H,1H,2H,2H-perfluorooctyl) silane, and acts as a reusable transferring layer. Uniformity of the thickness of the patterned PDMS layer and the well-alignment could be achieved due to the transparency and proper flexibility of this transferring layer. Surface treatment results are confirmed by XPS and contact angle testing, while bonding forces between different layers were measured for better understanding of the transferring process. We have also designed and fabricated a few simple types of 3D PDMS chip, especially one consisting of 6 thin layers (each with thickness of 50 μm), to demonstrate the potential utilization of this technique. 3D fluorescence images were taken by a confocal microscope to illustrate the spatial characters of essential parts. This fabrication method is confirmed to be fast, simple, repeatable, low cost and possible to be mechanized for mass production. © The Royal Society of Chemistry 2010.

Triple-Layer Vascular Grafts Fabricated by Combined E-Jet 3D Printing and Electrospinning.

Science.gov (United States)

Huang, Ruiying; Gao, Xiangkai; Wang, Jian; Chen, Haoxiang; Tong, Chunyi; Tan, Yongjun; Tan, Zhikai

2018-05-29

Small-diameter tissue-engineered vascular grafts are urgently needed for clinic arterial substitute. To simulate the structures and functions of natural blood vessels, we designed a novel triple-layer poly(ε-caprolactone) (PCL) fibrous vascular graft by combining E-jet 3D printing and electrospinning techniques. The resultant vascular graft consisted of an interior layer comprising 3D-printed highly aligned strong fibers, a middle layer made by electrospun densely fibers, and an exterior structure composed of mixed fibers fabricated by co-electrospraying. The biocompatible triple-layer graft was used for in vivo implantation, and results demonstrated that the longitudinally-aligned fibers within the lumen of the graft could enhance the proliferation and migration of endothelial cells, while maintained good mechanical properties. The exterior layer provided a pathway that encouraged cells to migrate into the scaffold after implantation. This experimental graft overcame the limitations of conventionally electrospun vascular grafts of inadequate porosity and lowly cell penetration. The unique structure of the triple-layer vascular graft promoted cell growth and infiltration in vivo, thus provided an encouraging substitute for in situ tissue engineering.

Fatigue-resistant epitaxial Pb(Zr,Ti)O3 capacitors on Pt electrode with ultra-thin SrTiO3 template layers

International Nuclear Information System (INIS)

Takahara, Seiichi; Morimoto, Akiharu; Kawae, Takeshi; Kumeda, Minoru; Yamada, Satoru; Ohtsubo, Shigeru; Yonezawa, Yasuto

2008-01-01

Lead zirconate-titanate Pb(Zr,Ti)O 3 (PZT) capacitors with Pt bottom electrodes were prepared on MgO substrates by pulsed laser deposition (PLD) technique employing SrTiO 3 (STO) template layer. Perovskite PZT thin films are prepared via stoichiometric target using the ultra-thin STO template layers while it is quite difficult to obtain the perovskite PZT on Pt electrode via stoichiometric target in PLD process. The PZT capacitor prepared with the STO template layer showed good hysteresis and leakage current characteristics, and it showed an excellent fatigue resistance. The ultra-thin STO template layers were characterized by angle-resolved X-ray photoelectron spectroscopy measurement. The effect of the STO template layer is discussed based on the viewpoint of the perovskite nucleation and diffusion of Pb and O atoms

The influence of charge injection from intermediate connectors on the performance of tandem organic light-emitting devices

Energy Technology Data Exchange (ETDEWEB)

Zhou, Dong-Ying [Institute of Functional Nano and Soft Materials (FUNSOM), Soochow University, Suzhou, Jiangsu 215123 (China); Department of Electrical and Computer Engineering and Waterloo Institute for Nanotechnology, University of Waterloo, 200 University Avenue West, Waterloo, Ontario N2L 3G1 (Canada); Siboni, Hossein Zamani; Wang, Qi; Aziz, Hany, E-mail: lsliao@suda.edu.cn, E-mail: h2aziz@uwaterloo.ca [Department of Electrical and Computer Engineering and Waterloo Institute for Nanotechnology, University of Waterloo, 200 University Avenue West, Waterloo, Ontario N2L 3G1 (Canada); Liao, Liang-Sheng, E-mail: lsliao@suda.edu.cn, E-mail: h2aziz@uwaterloo.ca [Institute of Functional Nano and Soft Materials (FUNSOM), Soochow University, Suzhou, Jiangsu 215123 (China)

2014-12-14

Charge generation in a typical intermediate connector, composed of “n-type doped layer/transition metal oxide (TMO)/hole transporting layer (HTL),” of a tandem organic light-emitting device (OLED) has recently been found to arise from charge transfer at the TMO/HTL interfaces. In this paper, we investigate the effect of hole injection barriers from intermediate connectors on the performance of tandem OLEDs. The hole injection barriers are caused by the offset of the highest occupied molecular orbital (HOMO) energy levels between HTLs contained in the intermediate connector and the top electroluminescence (EL) unit. We also find that although charge generation can occur at the interfaces between the TMO and a wide variety of HTLs of different HOMO values, an increase in the hole injection barrier however limits the electroluminescence efficiency of the top EL units. In the case of large hole injection barriers, significant charge accumulation in the HTLs makes the intermediate connector lose its functionality gradually over operating time, and limits device stability.

Thermoelectric Response in Single Quintuple Layer Bi2Te3

KAUST Repository

Sharma, S.

2016-10-05

Because Bi2Te3 belongs to the most important thermoelectric materials, the successful exfoliation of a single quintuple layer has opened access to an interesting two-dimensional material. For this reason, we study the thermoelectric properties of single quintuple layer Bi2Te3 by considering both the electron and phonon transport. On the basis of first-principles density functional theory, the electronic and phononic contributions are calculated by solving Boltzmann transport equations. The dependence of the lattice thermal conductivity on the phonon mean free path is evaluated along with the contributions of the acoustic and optical branches. We find that the thermoelectric response is significantly better for p- than for n-doping. By optimizing the carrier concentration, at 300 K, a ZT value of 0.77 is achieved, which increases to 2.42 at 700 K.

Growth, characterization, and waveguide lasing of Yb3+, Lu3+, Gd3+ co-doped KY(WO4)2 thin layers

NARCIS (Netherlands)

Aravazhi, S.; Geskus, D.; Günther, D.; Worhoff, Kerstin; Pollnau, Markus

2009-01-01

Monoclinic crystals of KY(WO4)2 (KYW) doped with different rare-earth ions are among the highly promising materials for building compact solid-state lasers. We report the liquid phase epitaxy (LPE) growth of 3-5 µm thick KYW:Gd3+, Lu3+, Yb3+ layers for Yb3+ concentrations of 1.2, 1.7, and 2.4 mol%

Improved charge trapping flash device with Al2O3/HfSiO stack as blocking layer

International Nuclear Information System (INIS)

Zheng Zhi-Wei; Huo Zong-Liang; Zhu Chen-Xin; Xu Zhong-Guang; Liu Jing; Liu Ming

2011-01-01

In this paper, we investigate an Al 2 O 3 /HfSiO stack as the blocking layer of a metal—oxide—nitride—oxide—silicon-type (MONOS) memory capacitor. Compared with a memory capacitor with a single HfSiO layer as the blocking layer or an Al 2 O 3 /HfO 2 stack as the blocking layer, the sample with the Al 2 O 3 /HfSiO stack as the blocking layer shows high program/erase (P/E) speed and good data retention characteristics. These improved performances can be explained by energy band engineering. The experimental results demonstrate that the memory device with an Al 2 O 3 /HfSiO stack as the blocking layer has great potential for further high-performance nonvolatile memory applications. (interdisciplinary physics and related areas of science and technology)

The Impedance of Multi-layer Vacuum Chambers

CERN Document Server

Vos, L

2003-01-01

Many components of the LHC vacuum chamber have multi-layered walls : the copper coated cold beam screen, the titanium coated ceramic chamber of the dump kickers, the ceramic chamber of the injection kickers coated with copper stripes, only to name a few. Theories and computer programs are available for some time already to evaluate the impedance of these elements. Nevertheless, the algorithm developed in this paper is more convenient in its application and has been used extensively in the design phase of multi-layer LHC vacuum chamber elements. It is based on classical transmission line theory. Closed expressions are derived for simple layer configurations, while beam pipes involving many layers demand a chain calculation. The algorithm has been tested with a number of published examples and was verified with experimental data as well.

Low-Temperature Process for Atomic Layer Chemical Vapor Deposition of an Al2O3 Passivation Layer for Organic Photovoltaic Cells.

Science.gov (United States)

Kim, Hoonbae; Lee, Jihye; Sohn, Sunyoung; Jung, Donggeun

2016-05-01

Flexible organic photovoltaic (OPV) cells have drawn extensive attention due to their light weight, cost efficiency, portability, and so on. However, OPV cells degrade quickly due to organic damage by water vapor or oxygen penetration when the devices are driven in the atmosphere without a passivation layer. In order to prevent damage due to water vapor or oxygen permeation into the devices, passivation layers have been introduced through methods such as sputtering, plasma enhanced chemical vapor deposition, and atomic layer chemical vapor deposition (ALCVD). In this work, the structural and chemical properties of Al2O3 films, deposited via ALCVD at relatively low temperatures of 109 degrees C, 200 degrees C, and 300 degrees C, are analyzed. In our experiment, trimethylaluminum (TMA) and H2O were used as precursors for Al2O3 film deposition via ALCVD. All of the Al2O3 films showed very smooth, featureless surfaces without notable defects. However, we found that the plastic flexible substrate of an OPV device passivated with 300 degrees C deposition temperature was partially bended and melted, indicating that passivation layers for OPV cells on plastic flexible substrates need to be formed at temperatures lower than 300 degrees C. The OPV cells on plastic flexible substrates were passivated by the Al2O3 film deposited at the temperature of 109 degrees C. Thereafter, the photovoltaic properties of passivated OPV cells were investigated as a function of exposure time under the atmosphere.

Systematic assessment of microneedle injection into the mouse cornea.

Science.gov (United States)

Matthaei, Mario; Meng, Huan; Bhutto, Imran; Xu, Qingguo; Boelke, Edwin; Hanes, Justin; Jun, Albert S

2012-06-20

Corneal intrastromal injection is an important mode of gene-vector application to subepithelial layers. In a mouse model, this procedure is substantially complicated by the reduced corneal dimensions. Furthermore, it may be difficult to estimate the corneal area reached by the volume of a single injection. This study aimed to investigate intrastromal injections into the mouse cornea using different microneedles and to quantify the effect of injecting varying volumes. A reproducible injection technique is described. Forty eyes of 20 129 Sv/J mice were tested. India ink was intrastromally injected using 30° beveled 33 G needles, tri-surface 25° beveled 35 G needles, or hand-pulled and 25° beveled glass needles. Each eye received a single injection of a volume of 1 or 2 μL. Corneoscleral buttons were fixed and flat mounted for computer-assisted quantification of the affected corneal area. Histological assessment was performed to investigate the intrastromal location of the injected dye. A mean corneal area of 5.0 ± 1.4 mm(2) (mean ± SD) and 7.7 ± 1.4 mm(2) was covered by intrastromal injections of 1 and 2 μL, respectively. The mean percentage of total corneal area reached ranged from 39% to 53% for 1 μL injections, and from 65% to 81% for 2 μL injections. Injections using the 33 G needles tended to provide the highest distribution area. Perforation rates were 8% for 30° beveled 33 G needles and 44% for tri-surface beveled 35 G needles. No perforation was observed with glass needle; however, intrastromal breakage of needle tips was noted in 25% of these cases. Intracorneal injection using a 30° beveled 33 G needle was safe and effective. The use of tri-surface beveled 35 G needles substantially increased the number of corneal perforations. Glass needles may break inside the corneal stroma. Injections of 1 μL and 2 μL resulted in an overall mean of 49% and 73% respectively of total corneal area involved.

Pt–Al2O3 dual layer atomic layer deposition coating in high aspect ratio nanopores

International Nuclear Information System (INIS)

Pardon, Gaspard; Gatty, Hithesh K; Stemme, Göran; Wijngaart, Wouter van der; Roxhed, Niclas

2013-01-01

Functional nanoporous materials are promising for a number of applications ranging from selective biofiltration to fuel cell electrodes. This work reports the functionalization of nanoporous membranes using atomic layer deposition (ALD). ALD is used to conformally deposit platinum (Pt) and aluminum oxide (Al 2 O 3 ) on Pt in nanopores to form a metal–insulator stack inside the nanopore. Deposition of these materials inside nanopores allows the addition of extra functionalities to nanoporous materials such as anodic aluminum oxide (AAO) membranes. Conformal deposition of Pt on such materials enables increased performances for electrochemical sensing applications or fuel cell electrodes. An additional conformal Al 2 O 3 layer on such a Pt film forms a metal–insulator–electrolyte system, enabling field effect control of the nanofluidic properties of the membrane. This opens novel possibilities in electrically controlled biofiltration. In this work, the deposition of these two materials on AAO membranes is investigated theoretically and experimentally. Successful process parameters are proposed for a reliable and cost-effective conformal deposition on high aspect ratio three-dimensional nanostructures. A device consisting of a silicon chip supporting an AAO membrane of 6 mm diameter and 1.3 μm thickness with 80 nm diameter pores is fabricated. The pore diameter is reduced to 40 nm by a conformal deposition of 11 nm Pt and 9 nm Al 2 O 3 using ALD. (paper)

Pt-Al2O3 dual layer atomic layer deposition coating in high aspect ratio nanopores

Science.gov (United States)

Pardon, Gaspard; Gatty, Hithesh K.; Stemme, Göran; van der Wijngaart, Wouter; Roxhed, Niclas

2013-01-01

Functional nanoporous materials are promising for a number of applications ranging from selective biofiltration to fuel cell electrodes. This work reports the functionalization of nanoporous membranes using atomic layer deposition (ALD). ALD is used to conformally deposit platinum (Pt) and aluminum oxide (Al2O3) on Pt in nanopores to form a metal-insulator stack inside the nanopore. Deposition of these materials inside nanopores allows the addition of extra functionalities to nanoporous materials such as anodic aluminum oxide (AAO) membranes. Conformal deposition of Pt on such materials enables increased performances for electrochemical sensing applications or fuel cell electrodes. An additional conformal Al2O3 layer on such a Pt film forms a metal-insulator-electrolyte system, enabling field effect control of the nanofluidic properties of the membrane. This opens novel possibilities in electrically controlled biofiltration. In this work, the deposition of these two materials on AAO membranes is investigated theoretically and experimentally. Successful process parameters are proposed for a reliable and cost-effective conformal deposition on high aspect ratio three-dimensional nanostructures. A device consisting of a silicon chip supporting an AAO membrane of 6 mm diameter and 1.3 μm thickness with 80 nm diameter pores is fabricated. The pore diameter is reduced to 40 nm by a conformal deposition of 11 nm Pt and 9 nm Al2O3 using ALD.

Tranport of p-aminohippuric acid (3H-PAH), inulin and dextran out of the cranial cavity: A methodological study using intraventricular injection and sample combustion

International Nuclear Information System (INIS)

Jakobson, Aa. M.

1987-01-01

Material injected into the cerebral ventricles can leave the cerebrospinal fluid (CSF) but remain in the cranial cavity. To analyze the disappearance of 3 H- and of 14 C-labelled material from the cranial cavity, such material was injected into the lateral ventricles together with a bulk flow marker, labelled with the other radionuclide. In the present pilot study 3 H-PAH and 14 C-inulin were used. Five μl of a mixture was injected into each lateral cerebral ventricles in rats, which were killed at various intervals. The whole skull was analyzed without opening the CSF space after homogenization in the deep-frozen state. The samples were combusted and analyzed by liquid scintillation counting. Probenecid, injected intraperitoneally, inhibited the removal of 3 H-PAH from the skull cavity, as anticipated. Immediately after the intraventricular injection, however, 3 H-PAH was transiently retained, probably by uptake into actively transporting tissue. After injection of probenecid, this delay in removal was reduced. The difference in disappearance rate between 3 H-PAH and 14 C-inulin was estimated by comparing the 3 H/ 14 C ratio in the skulls with that in the injected solution, which appeared to be a better method than comparing the recovery of each compound. (author)

The silicon-silicon oxide multilayers utilization as intrinsic layer on pin solar cells

International Nuclear Information System (INIS)

Colder, H.; Marie, P.; Gourbilleau, F.

2008-01-01

Silicon nanostructures are promising candidate for the intrinsic layer on pin solar cells. In this work we report on new material: silicon-rich silicon oxide (SRSO) deposited by reactive magnetron sputtering of a pure silica target and an interesting structure: multilayers consisting of a stack of SRSO and pure silicon oxide layers. Two thicknesses of the SRSO sublayer, t SRSO , are studied 3 nm and 5 nm whereas the thickness of silica sublayer is maintaining at 3 nm. The presence of nanocrystallites of silicon, evidenced by X-Ray diffraction (XRD), leads to photoluminescence (PL) emission at room temperature due to the quantum confinement of the carriers. The PL peak shifts from 1.3 eV to 1.5 eV is correlated to the decreasing of t SRSO from 5 nm down to 3 nm. In the purpose of their potential utilization for i-layer, the optical properties are studied by absorption spectroscopy. The achievement a such structures at promising absorption properties. Moreover by favouring the carriers injection by the tunnel effect between silicon nanograins and silica sublayers, the multilayers seem to be interesting for solar cells

Methodological study on determining endogenous amino acid excretion of broiler chickens by single intravenous injection of 3H-leucine

International Nuclear Information System (INIS)

Yao Junhu; Wang Kangning; Yang Feng; Zhou Anguo; Cai Xuelin; Duanmu Dao

1999-01-01

Forty broiler chickens (1.5 kg of body weight, BW) were randomly divided into 20 groups. Every fifth group was force-fed a nitrogen-free diet (NFD) or a NFd + 3.20% enzyme hydrolysed casein (EHC) diet or diets with 5% and 20% crude protein (CP) in which soybean meal (sol.) was the sole nitrogen source. 30μCi 3 H-leucine/kg BW was intravenously injected into all birds just after the force-feeding. Venous blood samples were taken at 5 min, 4h, 24h, 36h and 48h after the injection, and the amount of excreta for the whole period of 48h was collected. The amino acids excreted after force-feeding NFD + 3.20% EHC of CP5% diet were theoretically endogenous. The ratios of specific radioactivity (SR) in excreta and the value of definite integral in free plasma from 0 to 48 h after injection of labelled leucine were not different (P > 0.05) when NFD, NFD + 3.20% EHC or CP5% diet was fed. From these results and theoretical analysis, it was suggested that for the birds with CP20% diet, the ratio of SR in endogenous leucine and value of definite integral in free plasma from 0 to 48 h after injection of labelled leucine would be the same as that of the birds with NFD diet, and thus endogenous losses of leucine and other amino acids, by the endogenous amino acid pattern measured with NFD diet, could be estimated for CP20% diet. The endogenous amino acid losses measured by this new technique was 120.50% of those measured by NFD method. It was suggested that single intravenous injection of 3 H-leucine first proposed would be more valuable for determining endogenous amino acid losses, especially when practical nitrogen-containing diet was fed

Subcutaneous injection of thallium-201 chloride and gallium-67 citrate at acupuncture point K-3; An animal experiment and human-being study

Energy Technology Data Exchange (ETDEWEB)

Johg, Shiang-Bin; Wu, Chung-Chieng; Chen, Ming-Feng; Wu, Sheng-Nan (Kaohsiung Medical Coll., Taiwan (China))

1992-09-01

Subcutaneous (SC) injection of [sup 99m]Tc pertechnetate ([sup 99m]Tc) at acupuncture points K-3 is a new method of lower-limb radionuclide venography. To investigate the mechanism of absorption of [sup 99m]Tc from SC injected sites into vascular system, various radioisotopes such as [sup 201]Tl chloride ([sup 201]Tl) and [sup 67]Ga citrate ([sup 67]Ga) were SC injected at K-3 points in animal and human-beings experiments. It was found that [sup 99m]Tc and [sup 201]Tl were absorbed rapidly from K-3 points through venous system and into whole body soft tissue. However, [sup 67]Ga with a larger effective ionic radius than [sup 201]Tl was not absorbed throughout the observation of 5 minutes. Furthermore, intravenous administration of digitalis, a Na[sup +]-K[sup +] pump blocker, did not inhibit the absorption of [sup 99m]Tc and [sup 201]Tl after SC injection at K-3 points. These results suggest that absorption of radionuclides on SC injection at K-3 points is mainly through the passive pathway of diffusion rather than the active transport, and the effective ionic radius may be a major factor influencing the absorption rate of the radionuclides. (author).

Treatment of central precocious puberty by subcutaneous injections of leuprorelin 3-month depot (11.25 mg).

Science.gov (United States)

Carel, Jean-Claude; Lahlou, Najiba; Jaramillo, Orlando; Montauban, Vincent; Teinturier, Cécile; Colle, Michel; Lucas, Christel; Chaussain, Jean Louis

2002-09-01

Depot GnRH agonists are widely used for the treatment of precocious puberty. Leuprorelin 3-month depot is currently used in adults but has not been evaluated in children. We evaluated the efficacy of this new formulation (11.25 mg every 3 months), for the suppression of gonadotropic activation and pubertal signs in children with central precocious puberty. We included 44 children (40 girls) with early-onset pubertal development in a 6-month open trial. The inclusion criteria were clinical pubertal development before the age of 8 (girls) or 10 (boys), advanced bone age, enlarged uterus (>36 mm), testosterone more than 1.7 nmol/liter (boys), and pubertal response of LH to GnRH (peak >5 IU/liter). The principal criterion for efficacy assessment, GnRH-stimulated LH peak less than 3 IU/liter, was met in 81 of 85 (95%) of the tests performed at months 3 and 6. The remaining four values were slightly above the threshold. The levels of sex steroids were also significantly reduced and clinical pubertal development was arrested. Plasma leuprorelin levels, measured every 30 d, were essentially stable after d 60. Local intolerance was noted after 10 of 86 injections (12%), and was mild in four cases, moderate in five cases, and severe in one. Among these 10 events, 4 consisted in local pain at injection's site. In conclusion, leuprorelin 3-month depot efficiently inhibits the gonadotropic axis in 95% of children with central precocious puberty studied for a 6-month period. This regimen allows the reduction of the number of yearly injections from 12 to 4.

Universality Results for Multi-Layer Hele-Shaw and Porous Media Flows

Science.gov (United States)

Daripa, Prabir

2012-11-01

Saffman-Taylor instability is a well known viscosity driven instability of an interface. Motivated by a need to understand the effect of various injection policies currently in practice for chemical enhanced oil recovery, we study linear stability of displacement processes in a Hele-Shaw cell involving injection of an arbitrary number of immiscible fluid phases in succession. This is a problem involving many interfaces. Universal stability results have been obtained for this multi-layer (multi-region) flow in the sense that the results hold with arbitrary number of interfaces. These stability results have been applied to design injection policies that are considerably less unstable than the pure Saffman-Taylor case. In particular, we determine specific values of the viscosity of the fluid layers corresponding to smallest unstable band. Moreover, we discuss universal selection principle of optimal viscous profiles. The talk is based on following papers. Qatar National Fund (a member of the Qatar Foundation).

Analysis of chemical dissolution of the barrier layer of porous oxide on aluminum thin films using a re-anodizing technique

Energy Technology Data Exchange (ETDEWEB)

Vrublevsky, I. [Department of Microelectronics, Belarusian State University of Informatics and Radioelectronics, 6 Brovka street, Minsk 220013 (Belarus)]. E-mail: nil-4-2@bsuir.edu.by; Parkoun, V. [Department of Microelectronics, Belarusian State University of Informatics and Radioelectronics, 6 Brovka street, Minsk 220013 (Belarus); Sokol, V. [Department of Microelectronics, Belarusian State University of Informatics and Radioelectronics, 6 Brovka street, Minsk 220013 (Belarus); Schreckenbach, J. [Institut fuer Chemie, Technische Universitaet Chemnitz, Chemnitz D-09107 (Germany)

2005-09-30

Chemical dissolution of the barrier layer of porous oxide formed on thin aluminum films (99.9% purity) in the 4% oxalic acid after immersion in 2 mol dm{sup -3} sulphuric acid at 50 deg. C has been studied. The barrier layer thickness before and after dissolution was calculated using a re-anodizing technique. It has been shown that above 57 V the change in the growth mechanism of porous alumina films takes place. As a result, the change in the amount of regions in the barrier oxide with different dissolution rates is observed. The barrier oxide contains two layers at 50 V: the outer layer with the highest dissolution rate and the inner layer with a low dissolution rate. Above 60 V the barrier oxide contains three layers: the outer layer with a high dissolution rate, the middle layer with the highest dissolution rate and the inner layer with a low dissolution rate. We suggest that the formation of the outer layer of barrier oxide with a high dissolution rate is linked with the injection of protons or H{sub 3}O{sup +} ions from the electrolyte into the oxide film at the anodizing voltages above 57 V.

Small-Volume Injections: Evaluation of Volume Administration Deviation From Intended Injection Volumes.

Science.gov (United States)

Muffly, Matthew K; Chen, Michael I; Claure, Rebecca E; Drover, David R; Efron, Bradley; Fitch, William L; Hammer, Gregory B

2017-10-01

In the perioperative period, anesthesiologists and postanesthesia care unit (PACU) nurses routinely prepare and administer small-volume IV injections, yet the accuracy of delivered medication volumes in this setting has not been described. In this ex vivo study, we sought to characterize the degree to which small-volume injections (≤0.5 mL) deviated from the intended injection volumes among a group of pediatric anesthesiologists and pediatric postanesthesia care unit (PACU) nurses. We hypothesized that as the intended injection volumes decreased, the deviation from those intended injection volumes would increase. Ten attending pediatric anesthesiologists and 10 pediatric PACU nurses each performed a series of 10 injections into a simulated patient IV setup. Practitioners used separate 1-mL tuberculin syringes with removable 18-gauge needles (Becton-Dickinson & Company, Franklin Lakes, NJ) to aspirate 5 different volumes (0.025, 0.05, 0.1, 0.25, and 0.5 mL) of 0.25 mM Lucifer Yellow (LY) fluorescent dye constituted in saline (Sigma Aldrich, St. Louis, MO) from a rubber-stoppered vial. Each participant then injected the specified volume of LY fluorescent dye via a 3-way stopcock into IV tubing with free-flowing 0.9% sodium chloride (10 mL/min). The injected volume of LY fluorescent dye and 0.9% sodium chloride then drained into a collection vial for laboratory analysis. Microplate fluorescence wavelength detection (Infinite M1000; Tecan, Mannedorf, Switzerland) was used to measure the fluorescence of the collected fluid. Administered injection volumes were calculated based on the fluorescence of the collected fluid using a calibration curve of known LY volumes and associated fluorescence.To determine whether deviation of the administered volumes from the intended injection volumes increased at lower injection volumes, we compared the proportional injection volume error (loge [administered volume/intended volume]) for each of the 5 injection volumes using a linear

The generation of post noon F3 layers over the dip equatorial location of Thiruvananthapuram- A new perspective

Science.gov (United States)

Mridula, N.; Pant, Tarun Kumar

2018-05-01

In the present paper, occurrence of post noon F3 layers over Thiruvananthapuram (8.5°N; 77°E; dip latitude ∼ 1.5 °N), a dip equatorial station in India have been investigated. F3 layers that occur beyond 13 IST and as observed using ground based ionosonde, for the years 2004-2008 have been studied. Our analysis shows that post noon F3 layers occur mostly on CEJ days around 16 IST to 18 IST. It is found that the time of the ionospheric E-region electric field reversal as inferred from collocated ground based magnetometer observations plays a crucial role in the generation of post noon F3 layers. In fact an early reversal of electric field emerged to be the necessary condition for the formation of post noon F3 layers. A time delay of three to 4 h is observed between the electric field reversal and the formation of F3 layer. It is proposed that this early reversal causes enhanced ionization over dip equatorial region, providing an additional ion drag to the flow of thermospheric zonal wind. This leads to accumulation of more ionization and neutrals culminating in the generation of post noon F3 layers as in the case of pre noon F3 layers. These results reveal that the generation of post noon F3 layers over the dip equatorial region is a natural consequence of the variability associated with the spatio-temporal evolution of EIA and prevailing thermospheric and ionospheric dynamics, and adds a new perspective to the present understanding.

Annual Report RCRA Post-Closure Monitoring and Inspections for CAU 91: Area 3 U-3fi Injection Well, Nevada Test Site, Nevada, for the period October 2000-October 2001

International Nuclear Information System (INIS)

Tobiason, D. S.

2002-01-01

This annual Neutron Soil Moisture Monitoring report provides an analysis and summary for site inspections, meteorological information, and neutron soil moisture monitoring data obtained at the U-3fi Injection Well during the October 2000 to October 2001 period. The U-3fi Injection Well is located in Area 3 of the Nevada Test Site (NTS), Nye County, Nevada. Inspections of the Area 3 U-3fi Injection Well are conducted to determine and document the physical condition of the concrete pad, facilities, and any unusual conditions that could impact the proper operation of the waste disposal unit closure. The objective of the neutron-logging program is to monitor the soil moisture conditions along the 128-meter (m) (420-ft) ER3-3 monitoring well and detect changes that may be indicative of moisture movement in the regulated interval extending between 73 to 82 m (240 to 270 ft) or to detect changes that may be indicative of subsidence within the disposal unit itself

Injecting risk behavior among traveling young injection drug users: travel partner and city characteristics.

Science.gov (United States)

Montgomery, Martha E; Fatch, Robin S; Evans, Jennifer L; Yu, Michelle; Davidson, Peter J; Page, Kimberly; Hahn, Judith A

2013-06-01

Young injection drug users (IDUs), a highly mobile population, engage in high levels of injecting risk behavior, yet little is understood about how such risk behavior may vary by the characteristics of the cities to which they travel, including the existence of a syringe exchange program (SEP), as well as travel partner characteristics. In 2004-2005, we conducted a 6-month prospective study to investigate the risk behavior of 89 young IDUs as they traveled, with detailed information gathered about 350 city visits. In multivariable analyses, travel to larger urban cities with a population of 500,000-1,000,000 was significantly associated with injecting drugs (adjusted odds ratio (AOR) = 3.71; 95 % confidence interval (CI), 1.56-8.82), ancillary equipment sharing (AES; AOR = 7.05; 95 % CI, 2.25-22.06) and receptive needle sharing (RNS; AOR = 5.73; 95 % CI, 1.11-27.95), as compared with visits to smaller cities with populations below 50,000. Region of the country, and the existence of a SEP within the city visited, were not independently associated with injecting drugs, AES, or RNS during city visits. Traveling with more than one injecting partner was associated with injecting drugs during city visits (AOR = 2.77; 95 % CI, 1.46-5.27), when compared with traveling alone. Additionally, both non-daily and daily/almost daily alcohol use during city visits were associated with AES (AOR = 3.37; 95 % CI, 1.42-7.68; AOR = 3.03; 95 % CI, 1.32-6.97, respectively) as compared with no alcohol consumption. Traveling young IDUs are more likely to inject when traveling with other IDUs and to engage in higher risk injection behavior when they are in large cities. Risk behavior occurring in city visits, including equipment sharing and alcohol consumption, suggests further need for focused interventions to reduce risk for viral infection among this population.