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Sample records for rapid isothermal anneals

  1. High Nitrogen Austenitic Stainless Steel Precipitation During Isothermal Annealing

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    Maria Domankova

    2016-07-01

    Full Text Available The time-temperature-precipitation in high-nitrogen austenitic stainless steel was investigated using light optical microscopy, transmission electron microscopy, selected area diffraction and energy-dispersive X-ray spectroscopy. The isothermal precipitation kinetics curves and the corresponding precipitation activation energy were obtained. The diffusion activation energy of M2N precipitation is 129 kJ/mol. The results show that critical temperature for M2N precipitation is about 825°C with the corresponding incubation period 2.5 min.

  2. a-Si:H crystallization from isothermal annealing and its dependence on the substrate used

    Energy Technology Data Exchange (ETDEWEB)

    Rojas-Lopez, M., E-mail: marlonrl@yahoo.com.mx [CIBA-Tlaxcala, Instituto Politecnico Nacional, Tepetitla, Tlax. 90700 (Mexico); Orduna-Diaz, A.; Delgado-Macuil, R.; Gayou, V.L.; Bibbins-Martinez, M. [CIBA-Tlaxcala, Instituto Politecnico Nacional, Tepetitla, Tlax. 90700 (Mexico); Torres-Jacome, A.; Trevino-Palacios, C.G. [INAOE, Tonantzintla, Puebla, Pue. 72000 (Mexico)

    2010-10-25

    We present hydrogenated amorphous silicon (a-Si:H) films which were deposited on two different substrates (glass and mono-crystalline silicon) after an isothermal annealing treatment at 250 deg. C for up to 14 h. The annealed amorphous films were analyzed using atomic force microscopy, Raman and FTIR spectroscopy. Films deposited on glass substrate experienced an amorphous-crystalline phase transition after annealing because of the metal-induced crystallization effect, reaching approximately 70% conversion after 14 h of annealing. An absorption frequency of the TO-phonon mode that varies systematically with the substoichiometry of the silicon oxide in the 1046-1170 cm{sup -1} region was observed, revealing the reactivity of the film with the annealing time. For similar annealing time, films deposited on mono-crystalline silicon substrate remained mainly amorphous with minimal Si-crystalline formation. Therefore, the crystalline formations and the shape of the films surfaces depends on the annealing time as well as on the substrate employed during the deposition process of the a-Si:H film.

  3. Rapid magnetic hardening by rapid thermal annealing in NdFeB-based nanocomposites

    Energy Technology Data Exchange (ETDEWEB)

    Chu, K.-T.; Jin, Z Q; Chakka, Vamsi M; Liu, J P [Department of Physics, University of Texas at Arlington, Arlington, TX 76019 (United States)

    2005-11-21

    A systematic study of heat treatments and magnetic hardening of NdFeB-based melt-spun nanocomposite ribbons have been carried out. Comparison was made between samples treated by rapid thermal annealing and by conventional furnace annealing. Heating rates up to 200 K s{sup -1} were adopted in the rapid thermal processing. It was observed that magnetic hardening can be realized in an annealing time as short as 1 s. Coercivity of 10.2 kOe in the nanocomposites has been obtained by rapid thermal annealing for 1 s, and prolonged annealing did not give any increase in coercivity. Detailed results on the effects of annealing time, temperature and heating rate have been obtained. The dependence of magnetic properties on the annealing parameters has been investigated. Structural characterization revealed that there is a close correlation between magnetic hardening and nanostructured morphology. The coercivity mechanism was also studied by analysing the magnetization minor loops.

  4. Isothermal annealing of a 620 nm optical absorption band in Brazilian topaz crystals

    Energy Technology Data Exchange (ETDEWEB)

    Isotani, Sadao, E-mail: sisotani@if.usp.br [Instituto de Física, Universidade de São Paulo, São Paulo (Brazil); Matsuoka, Masao [Instituto de Física, Universidade de São Paulo, São Paulo (Brazil); Albuquerque, Antonio Roberto Pereira Leite [University Federal of São Paulo, São Paulo (Brazil)

    2013-04-15

    Isothermal decay behaviors, observed at 515, 523, 562, and 693 K, for an optical absorption band at 620 nm in gamma-irradiated Brazilian blue topaz were analyzed using a kinetic model consisting of O{sup −} bound small polarons adjacent to recombination centers (electron traps). The kinetic equations obtained on the basis of this model were solved using the method of Runge–Kutta and the fit parameters describing these defects were determined with a grid optimization method. Two activation energies of 0.52±0.08 and 0.88±0.13 eV, corresponding to two different structural configurations of the O{sup −} polarons, explained well the isothermal decay curves using first-order kinetics expected from the kinetic model. On the other hand, thermoluminescence (TL) emission spectra measured at various temperatures showed a single band at 400 nm in the temperature range of 373–553 K in which the 620 nm optical absorption band decreased in intensity. Monochromatic TL glow curve data at 400 nm extracted from the TL emission spectra observed were found to be explained reasonably by using the knowledge obtained from the isothermal decay analysis. This suggests that two different structural configurations of O{sup −} polarons are responsible for the 620 nm optical absorption band and that the thermal annealing of the polarons causes the 400 nm TL emission band.

  5. Rapid and long-term gamma-radiation annealing in low-dropout voltage regulators

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    Vukić Vladimir Đ.

    2017-01-01

    Full Text Available Samples of four types of low-dropout voltage regulators, with both serial pnp and npn transistors, were examined in room-temperature isothermal gamma radiation annealing. After uninterrupted exposure to a total ionising dose of 500 Gy, biased and loaded voltage regulators were examined in room-temperature annealing within the first 30 minutes after the exposure. Beside the on-line measurement of output voltage and quiescent current during the thirty-minute period immediately after irradiation, also results were procured after 10-year room-temperature spontaneous recovery. Data obtained during the irradiation and rapid annealing were fitted with linear, exponential, and power-law regression functions. A simple procedure was proposed, based on the quiescent current annealing factor, for the quick estimation of the integrated voltage regulator's radiation sensitivity during the post-irradiation isothermal annealing. In order to estimate the circuit's radiation sensitivity, immediately after irradiation, tested devices have to be left in the same operating conditions as during the exposure. If a clear trend of the quiescent current recovery can be observed, further examinations have to be implemented to estimate if a circuit is acceptably radiation-tolerant. If no recovery trend can be observed within the first hour after irradiation, or even further degradation is noticed, then the examined voltage regulator is a radiation-sensitive device and cannot be used in radiation environments. The described procedure is based on the macroscopic effects of the radiation-induced charge-trapping in field oxides and interfaces. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. 171007: Physical and functional effects of the interaction of radiation with electrical and biological systems

  6. Rapid hardening induced by electric pulse annealing in nanostructured pure aluminum

    DEFF Research Database (Denmark)

    Zeng, Wei; Shen, Yao; Zhang, Ning

    2012-01-01

    source-limited hardening” mechanism. However, the hardening kinetics was substantially faster for the electric pulse annealed material. Detailed microstructural characterization suggested that the rapid hardening during electric pulse annealing is related to an enhanced rate of recovery of dislocation...

  7. AFM and FTIR characterization of microcrystalline Si obtained from isothermal annealing of Al/a-Si:H

    Energy Technology Data Exchange (ETDEWEB)

    Rojas-Lopez, M.; Orduna-Diaz, A.; Delgado-Macuil, R. [Centro de Investigacion en Biotecnologia Aplicada (CIBA), IPN, Tlaxcala, Tlax. 72197 (Mexico); Olvera-Hernandez, J. [Centro de Investigacion en Dispositivos Semiconductores (CIDS), BUAP, Puebla, Pue. 72570 (Mexico); Navarro-Contreras, H.; Vidal, M.A.; Saucedo, N.; Mendez-Garcia, V.H. [Instituto de Investigacion en Comunicacion Optica (IICO), UASLP, San Luis Potosi, S.L.P. 78100 (Mexico)

    2007-04-15

    Atomic force microscopy and Fourier transform infrared spectroscopy were used to investigate the morphology of the microcrystalline surface, and also the amorphous-crystalline structural transformation of a-Si:H films, isothermally annealed during several hours. Crystallization process was strongly influenced by the deposition of an Al layer on the surface of a-Si:H samples. Representative AFM images show the presence of grains, which increase in diameter with the annealing time. Relative crystallized fraction as a function of the annealing time can be described adequately by using the Avrami equation. The kinetic of this crystallization process suggest a two-dimensional growth of the Si nuclei. Fourier transform infrared measurements show the presence of an intense band near 512 cm{sup -1} associated to Si-Si bonding. We observed the relative diminishing of the intensity of the Si-H wagging mode at 694 cm{sup -1} with annealing time, suggesting effusion of hydrogen to the surface of microcrystalline films. (copyright 2007 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  8. Rapid and fully automated Measurement of Water Vapor Sorption Isotherms

    DEFF Research Database (Denmark)

    Arthur, Emmanuel; Tuller, Markus; Møldrup, Per

    2014-01-01

    Eminent environmental challenges such as remediation of contaminated sites, the establishment and maintenance of nuclear waste repositories, or the design of surface landfill covers all require accurate quantification of the soil water characteristic at low water contents. Furthermore, several...... and pesticide volatilization, toxic organic vapor sorption kinetics, and soil water repellency are illustrated. Several methods to quantify hysteresis effects and to derive soil clay content and specific surface area from VSA-measured isotherms are presented. Besides above mentioned applications, potential...... essential but difficult-to-measure soil properties such as clay content and specific surface area are intimately related to water vapor sorption. Until recently, it was a major challenge to accurately measure detailed water vapor sorption isotherms within an acceptable time frame. This priority...

  9. Evolution of nano-structures of silver due to rapid thermal annealing

    Energy Technology Data Exchange (ETDEWEB)

    Mondal, Shyamal, E-mail: shyamal.mondal@saha.ac.in; Bhattacharyya, S. R., E-mail: shyamal.mondal@saha.ac.in [Saha Institute of Nuclear Physics, 1/AF Bidhan Nagar, Kolkata-700064 (India)

    2014-04-24

    This report deals with rapid thermal annealing (RTA) effect on continuous silver film on Si(100) substrate. For this purpose silver films of different thicknesses were deposited and subsequently annealed at 500 and 800 °C. The as-deposited and annealed samples were investigated by scanning electron microscope (SEM). Formations of different nano-structures have been observed. Fragmentation of formed nanoislands also observed at temperature below melting temperature.

  10. Microstructure, Texture Evolution and Mechanical Properties of VT3-1 Titanium Alloy Processed by Multi-Pass Drawing and Subsequent Isothermal Annealing

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    Xiaofei Lei

    2017-04-01

    Full Text Available Microstructure, texture evolution, and mechanical properties of Ti–6Al–1.5Cr–2.5Mo–0.5Fe–0.3Si (VT3-1 titanium alloy processed by multi-pass drawing and subsequent isothermal annealing were systematically investigated. A fiber-like microstructure is formed after warm drawing at 760 °C with 60% area reduction. After isothermal annealing, the samples deformed to different amounts of area reduction show a similar volume fraction (80% of α phase, while the sample deformed to 60% exhibits a homogeneous microstructure with a larger grain size (5.8 μm. The major texture component of α phase developed during warm drawing is centered at a position of {φ1 = 10°, φ = 65°, φ2 = 0°}. The textures for annealed samples are almost along the orientation of original deformation textures and show significant increases in orientation density and volume fraction compared with their deformed states. In addition, for the drawn samples, the ultimate tensile strength increases but the ductility decreases with increasing drawing deformation. A negative slope of yield strength of annealed samples versus grain size (d−1/2 is found due to the difference between texture softening for as-rolled + annealed state and texture hardening for drawn + annealed state. The mechanical properties of annealed samples are found to be strongly dependent on grain size and texture, resulting in the balance of the strength and ductility.

  11. Crystallization and activation of silicon by microwave rapid annealing

    Science.gov (United States)

    Kimura, Shunsuke; Ota, Kosuke; Hasumi, Masahiko; Suzuki, Ayuta; Ushijima, Mitsuru; Sameshima, Toshiyuki

    2016-07-01

    A combination of the carbon-powder absorber with microwave irradiation is proposed as a rapid heat method. 2-μm-diameter carbon powders with a packing density of 0.08 effectively absorbed 2.45 GHz 1000-W-microwave and heated themselves to 1163 °C for 26 s. The present heat treatment recrystallized n-type crystalline silicon surfaces implanted with 1.0 × 10^{15}hbox {-cm}^{-2}-boron and phosphorus atoms with crystalline volume ratios of 0.99 and 0.93, respectively, by microwave irradiation at 1000 W for 20 s. Activation and carrier generation were simultaneously achieved with a sheet resistivity of 62 Ω / hbox {sq}. A high photo-induced-carrier effective lifetime of 1.0 × 10^{-4} s was also achieved. Typical electrical current-rectified characteristic and solar cell characteristic with an efficiency of 12.1 % under 100-mW/cm2-air-mass-1.5 illumination were obtained. Moreover, heat treatment with microwave irradiation at 1000 W for 22 s successfully crystallized silicon thin films with thicknesses ranging from 2.4 to 50 nm formed on quartz substrates. Nano-crystalline cluster structure with a high volume ratio of 50 % was formed in the 1.8-nm (initial 2.4-nm)-thick silicon films. Photoluminescence around 1.77 eV was observed for the 1.8-nm-thick silicon films annealed at 260 °C in 1.3 × 106-Pa-H2O-vapor for 3 h after the microwave heating.

  12. Rapid thermal annealing and crystallization mechanisms study of silicon nanocrystal in silicon carbide matrix

    Directory of Open Access Journals (Sweden)

    Wan Zhenyu

    2011-01-01

    Full Text Available Abstract In this paper, a positive effect of rapid thermal annealing (RTA technique has been researched and compared with conventional furnace annealing for Si nanocrystalline in silicon carbide (SiC matrix system. Amorphous Si-rich SiC layer has been deposited by co-sputtering in different Si concentrations (50 to approximately 80 v%. Si nanocrystals (Si-NC containing different grain sizes have been fabricated within the SiC matrix under two different annealing conditions: furnace annealing and RTA both at 1,100°C. HRTEM image clearly reveals both Si and SiC-NC formed in the films. Much better "degree of crystallization" of Si-NC can be achieved in RTA than furnace annealing from the research of GIXRD and Raman analysis, especially in high-Si-concentration situation. Differences from the two annealing procedures and the crystallization mechanism have been discussed based on the experimental results.

  13. Isothermal DNA origami folding: avoiding denaturing conditions for one-pot, hybrid-component annealing

    Science.gov (United States)

    Kopielski, Andreas; Schneider, Anne; Csáki, Andrea; Fritzsche, Wolfgang

    2015-01-01

    The DNA origami technique offers great potential for nanotechnology. Using biomolecular self-assembly, defined 2D and 3D nanoscale DNA structures can be realized. DNA origami allows the positioning of proteins, fluorophores or nanoparticles with an accuracy of a few nanometers and enables thereby novel nanoscale devices. Origami assembly usually includes a thermal denaturation step at 90 °C. Additional components used for nanoscale assembly (such as proteins) are often thermosensitive, and possibly damaged by such harsh conditions. They have therefore to be attached in an extra second step to avoid defects. To enable a streamlined one-step nanoscale synthesis - a so called one-pot folding - an adaptation of the folding procedures is required. Here we present a thermal optimization of this process for a 2D DNA rectangle-shaped origami resulting in an isothermal assembly protocol below 60 °C without thermal denaturation. Moreover, a room temperature protocol is presented using the chemical additive betaine, which is biocompatible in contrast to chemical denaturing approaches reported previously.The DNA origami technique offers great potential for nanotechnology. Using biomolecular self-assembly, defined 2D and 3D nanoscale DNA structures can be realized. DNA origami allows the positioning of proteins, fluorophores or nanoparticles with an accuracy of a few nanometers and enables thereby novel nanoscale devices. Origami assembly usually includes a thermal denaturation step at 90 °C. Additional components used for nanoscale assembly (such as proteins) are often thermosensitive, and possibly damaged by such harsh conditions. They have therefore to be attached in an extra second step to avoid defects. To enable a streamlined one-step nanoscale synthesis - a so called one-pot folding - an adaptation of the folding procedures is required. Here we present a thermal optimization of this process for a 2D DNA rectangle-shaped origami resulting in an isothermal assembly

  14. Isothermal Cold Crystallization, Heat Resistance, and Tensile Performance of Polylactide/Thermoplastic Polyester Elastomer (PLA/TPEE Blends: Effects of Annealing and Reactive Compatibilizer

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    Sisi Wang

    2016-12-01

    Full Text Available The combined influences of crystallinity and reactive compatibilizer—a multifunctional epoxide (ADR—on morphology, tensile performance, and heat resistance of polylactide/thermoplastic polyester elastomer (PLA/TPEE (80/20 blends were investigated. Annealing involved an isothermal cold crystallization of PLA matrix was performed to increase crystallinity of the samples. First, isothermal cold crystallization kinetics were investigated using differential scanning calorimetry measurement. It was found that the addition of ADR decreased the crystallization rate of the samples. The maximum crystallinity of the annealed samples also decreased from 40% to 34% while ADR loading increased from zero to 1.0 phr. Furthermore, influence of crystallinity on mechanical performances of the PLA/TPEE sample was researched. The heat resistance of the sample showed a significant enhancement while increasing its crystallinity. Meanwhile, the tensile ductility of the crystallized PLA/TPEE sample became very poor due to the embrittlement with increased crystallinity and the incompatibility between PLA and TPEE. However, the annealed PLA/TPEE/ADR samples with high crystallinity kept a higher tensile ductility because ADR greatly improved the interfacial compatibility. Differences in tensile fracture behaviors of the quenched and annealed PLA/TPEE samples with and without ADR were discussed in detail. At last, crystallized PLA/TPEE/ADR blends with excellent heat resistance and high tensile ductility were obtained by annealing and reactive compatibilization.

  15. Epitaxial nickel and cobalt suicide formation by rapid thermal annealing

    Science.gov (United States)

    Chevallier, J.; Larsen, A. Nylandsted

    1986-02-01

    Thin films of epitaxial NiSi2 and CoSi2 were formed by short-duration incoherent light exposure of evaporated Ni or Co films on Si single crystals. The crystalline quality of these suicides is comparable to what has been obtained for long-duration furnace annealed suicides, as deduced from channeling measurements. NiSi2 is of high crystalline quality at all temperatures at which it is formed whereas the CoSi2 films recrystallize at a temperature of ˜980°C.

  16. Morphology of oxygen precipitates in silicon wafers pre-treated by rapid thermal annealing

    Energy Technology Data Exchange (ETDEWEB)

    Kot, D., E-mail: kot@ihp-microelectronics.com; Kissinger, G.; Schubert, M. A. [IHP, Im Technologiepark 25, 15236 Frankfurt (Oder) (Germany); Sattler, A. [Siltronic AG, Hanns-Seidel-Platz 4, 81737 München (Germany)

    2014-05-05

    The morphology of oxygen precipitates in Czochralski silicon wafers pre-treated by rapid thermal annealing (RTA) and subjected to a heat treatment in the temperature range between 800 °C and 1000 °C was investigated by scanning transmission electron microscopy. The samples were pre-treated by RTA in order to establish a defined supersaturation of vacancies. It was found that in such vacancy-rich samples subjected to an annealing at 800 °C three dimensional dendrites are formed. Until now, it was known that during annealing at 800 °C plate-like oxygen precipitates are formed.

  17. Rapid Newcastle Disease Virus Detection Based on Loop-Mediated Isothermal Amplification and Optomagnetic Readout

    DEFF Research Database (Denmark)

    Tian, Bo; Ma, Jing; Zardán Gómez de la Torre, Teresa

    2016-01-01

    efficiency of loop-mediated isothermal amplification (LAMP) with an optomagnetic nanoparticle-based readout system, we demonstrate ultrasensitive and rapid detection of Newcastle disease virus RNA. Biotinylated amplicons of LAMP and reverse transcription LAMP (RT-LAMP) bind to streptavidin-coated magnetic...

  18. Growth of Ni2Si by rapid thermal annealing: Kinetics and moving species

    Science.gov (United States)

    Ma, E.; Lim, B. S.; Nicolet, M.-A.; Natan, M.

    1987-10-01

    The growth kinetics is characterized and the moving species is identified for the formation of Ni2Si by Rapid Thermal Annealing (RTA) of sequentially deposited Si and Ni films on a Si substrate. The interfacial Ni2Si layer grows as the square root of time, indicating that the suicide growth process is diffusion-limited. The activation energy is 1.25±0.2 eV in the RTA temperature range of 350 450° C. The results extend those of conventional steady-state furnace annealing quite fittingly, and a common activation energy of 1.3±0.2 eV is deduced from 225° to 450° C. The marker experiment shows that Ni is the dominant moving species during Ni2Si formation by RTA, as is the case for furnace annealing. It is concluded that the two annealing techniques induce the same growth mechanisms in Ni2Si formation.

  19. Synthesis of B–Sb by rapid thermal annealing of B/Sb multilayer films

    Indian Academy of Sciences (India)

    layer with predetermined thickness of boron and antimony and subsequently subjecting the multilayer to rapid thermal annealing. The films were characterized by measuring microstructural, optical and compositional properties. 2. Experimental. Multilayer films of B and Sb were deposited onto Si and fused silica substrates ...

  20. Structural and compositional properties of CZTS thin films formed by rapid thermal annealing of electrodeposited layers

    Science.gov (United States)

    Lehner, J.; Ganchev, M.; Loorits, M.; Revathi, N.; Raadik, T.; Raudoja, J.; Grossberg, M.; Mellikov, E.; Volobujeva, O.

    2013-10-01

    In this work Cu2ZnSnS4 (CZTS) thin films were formed by rapid thermal annealing (RTA) of sequentially electrodeposited Cu-Zn and Sn films in 5% H2S containing atmosphere. Six different thermal profiles were used in the experiments. In three of these, the temperature ramping up was varied, while the variable in the other three profiles was the cooling down rate. The optimising parameters for RTA of electrodeposited films were found and annealed films were characterised by X-ray diffraction (XRD), micro-Raman spectroscopy, scanning electron microscopy and energy dispersive X-ray spectroscopy (SEM+EDS). The material parameters such as lattice strain and crystallite size were also determined and the influence of annealing temperature and heating rate on these parameters was discussed.The pathway of MoS2 formation was investigated.

  1. Influence of Rapid Thermal Annealing on the Characteristics of InGaN/GaN MQWs

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    Tian Yuan

    2016-01-01

    Full Text Available N-type InGaN/GaN multiple-quantum-wells (MQWs were grown on sapphire substrates by metal organic chemical vapor deposition (MOCVD. The crystal quality and optical properties of samples after rapid thermal annealing (RTA at different temperatures in a range from 400 to 800°C are investigated by X-ray diffraction (XRD and photoluminescence (PL spectrum. The experimental results show that the peaks of InGaN, InN and In can be observed in all samples. And the results are induced by the phase separation and In-clusters. The luminescence peak of the samples annealed showed a red shift. It is caused by strain stress relaxation during the RTA process. Furthermore, some defects can be eliminated and the best annealing temperature is from 500°C to 700°C.

  2. Rapid thermal annealing of FePt and FePt/Cu thin films

    Energy Technology Data Exchange (ETDEWEB)

    Brombacher, Christoph

    2011-01-10

    Chemically ordered FePt is one of the most promising materials to reach the ultimate limitations in storage density of future magnetic recording devices due to its high uniaxial magnetocrystalline anisotropy and a corrosion resistance superior to rare-earth based magnets. In this study, FePt and FePt/Cu bilayers have been sputter deposited at room temperature onto thermally oxidized silicon wafers, glass substrates and self-assembled arrays of spherical SiO{sub 2} particles with diameters down to 10 nm. Millisecond flash lamp annealing, as well as conventional rapid thermal annealing was employed to induce the phase transformation from the chemically disordered A1 phase into the chemically ordered L1{sub 0} phase. The influence of the annealing temperature, annealing time and the film thickness on the ordering transformation and (001) texture evolution of FePt films with near equiatomic composition was studied. Whereas flash lamp annealed FePt films exhibit a polycrystalline morphology with high chemical L1{sub 0} order, rapid thermal annealing can lead to the formation of chemically ordered FePt films with (001) texture on amorphous SiO{sub 2}/Si substrates. The resultant high perpendicular magnetic anisotropy and large coercivities up to 40 kOe are demonstrated. Simultaneously to the ordering transformation, rapid thermal annealing to temperatures exceeding 600 C leads to a break up of the continuous FePt film into separated islands. This dewetting behavior was utilized to create regular arrays of FePt nanostructures on SiO{sub 2} particle templates with periods down to 50 nm. The addition of Cu improves the (001) texture formation and chemical ordering for annealing temperatures T{sub a} {<=}600 C. In addition, the magnetic anisotropy and the coercivity of the ternary FePtCu alloy can be effectively tailored by adjusting the Cu content. The prospects of FePtCu based exchange spring media, as well as the magnetic properties of FePtCu nanostructures fabricated

  3. Rapid annealing of severely deformed low carbon steel in subcritical temperature range

    Science.gov (United States)

    Ghiabakloo, H.; Kazeminezhad, M.

    2017-09-01

    A low-carbon steel sheet containing 0.05 C, 0.203 Mn, and 0.0229 Si (all in wt%) was rapidly annealed in a temperature range of 300 °C to 600 °C after severe plastic deformation by using constrained groove pressing (CGP) technique. Microstructure evolution was investigated by scanning electron and optical microscopes. Mechanical properties were evaluated by hardness measurements and shear punch test. The results showed a thermal stability up to 400 °C where recrystallization did not occur in the specimens even after 7200 s. This thermal stability is in agreement with previously reported results of conventional annealing of the same steel after CGP. However, annealing at 500 °C and 600 °C led to recrystallization which started after holding times of 600 s and 20 s, respectively. Longer holding times resulted to grain growth and deterioration of strength and hardness, but the final strength and hardness were still higher than those of conventionally annealed specimens. The reason has been attributed to no abnormal grain growth in the present study, in contrast to that occurs after conventional annealing of CGPed low carbon steel. The kinetics of recrystallization at 600 °C was studied using the celebrated Johnson-Mehl-Avrami-Kolmogorov (JMAK) model; the results showed a bi-linear JMAK plot indicating two different stages of recrystallization rate before and after 70% recrystallization.

  4. Rapid preparation of solution-processed InGaZnO thin films by microwave annealing and photoirradiation

    Directory of Open Access Journals (Sweden)

    Heajeong Cheong

    2015-06-01

    Full Text Available We fabricated solution-processed indium–gallium–zinc oxide (IGZO thin-film transistors (TFTs by microwave (MW annealing an IGZO precursor film followed by irradiating with vacuum ultraviolet (VUV light. MW annealing allows more rapid heating of the precursor film than conventional annealing processes using a hot plate or electric oven and promotes the crystallization of IGZO. VUV irradiation was used to reduce the duration and temperature of the post-annealing step. Consequently, the IGZO TFTs fabricated through MW annealing for 5 min and VUV irradiation for 1 min exhibited an on/off current ratio of 108 and a field-effect mobility of 0.3 cm2 V−1 s−1. These results indicate that MW annealing and photoirradiation is an effective combination for annealing solution processed IGZO precursor films to prepare the semiconductor layers of TFTs.

  5. Formation and Device Application of Ge Nanowire Heterostructures via Rapid Thermal Annealing

    OpenAIRE

    Tang, Jianshi; Wang, Chiu-Yen; Xiu, Faxian; Zhou, Yi; Chen, Lih-Juann; Wang, Kang L.

    2011-01-01

    We reviewed the formation of Ge nanowire heterostructure and its field-effect characteristics by a controlled reaction between a single-crystalline Ge nanowire and Ni contact pads using a facile rapid thermal annealing process. Scanning electron microscopy and transmission electron microscopy demonstrated a wide temperature range of 400~500°C to convert the Ge nanowire to a single-crystalline Ni2Ge/Ge/Ni2Ge nanowire heterostructure with atomically sharp interfaces. More importantly, we studie...

  6. Loop-mediated Isothermal Amplification Assay to Rapidly Detect Wheat Streak Mosaic Virus in Quarantined Plants

    Directory of Open Access Journals (Sweden)

    Siwon Lee

    2015-12-01

    Full Text Available We developed a loop-mediated isothermal amplification (LAMP method to rapidly diagnose Wheat streak mosaic virus (WSMV during quarantine inspections of imported wheat, corn, oats, and millet. The LAMP method was developed as a plant quarantine inspection method for the first time, and its simplicity, quickness, specificity and sensitivity were verified compared to current reverse transcription-polymerase chain reaction (RT-PCR and nested PCR quarantine methods. We were able to quickly screen for WSMV at quarantine sites with many test samples; thus, this method is expected to contribute to plant quarantine inspections.

  7. Development of a loop-mediated isothermal amplification assay for rapid detection of Burkholderia mallei.

    Science.gov (United States)

    Mirzai, S; Safi, S; Mossavari, N; Afshar, D; Bolourchian, M

    2016-08-31

    The present study was conducted to establish a Loop-mediated isothermal amplification (LAMP) technique for the rapid detection of B. mallei the etiologic agent of glanders, a highly contagious disease of equines. A set of six specific primers targeting integrase gene cluster were designed for the LAMP test. The reaction was optimized using different temperatures and time intervals. The specificity of the assay was evaluated using DNA from B.pseudomallei and Pseudomonas aeruginosa. The LAMP products were analyzed both visually and under UV light after electrophoresis. The optimized conditions were found to be at 63ºC for 60 min. The assay showed high specificity and sensitivity. It was concluded that the established LAMP assay is a rapid, sensitive and practical tool for detection of B. mallei and early diagnosis of glanders.

  8. Rapid detection of Candida albicans in oral exfoliative cytology samples by loop-mediated isothermal amplification.

    Science.gov (United States)

    Noguchi, Hiroyasu; Iwase, Takashi; Omagari, Daisuke; Asano, Masatake; Nakamura, Ryota; Ueki, Kosuke; Shinozuka, Keiji; Kaneko, Tadayoshi; Tonogi, Morio; Ohki, Hiderou

    2017-01-01

    Loop-mediated isothermal amplification (LAMP) rapidly amplifies DNA under isothermal conditions. The aim of this study was to detect Candida albicans and compare the positivity rate in the LAMP reaction with that of conventional methods for oral exfoliative cytology (EC) samples. Sixty-eight EC samples from 53 patients were subjected to LAMP analysis. These patients had been clinically diagnosed with leukoplakia, squamous cell carcinoma, oral lichen planus (OLP), stomatitis, oral candidiasis, and other malignancies. LAMP reactions were defined as positive when the sample turbidity exceeded 0.1 (arbitrary unit). Periodic acid-Schiff (PAS) staining and microbial culture were also performed to detect Candida species in EC samples. The LAMP reaction detected C. albicans in 42.6% of EC samples. Candida species were detected in 32.4% of the same samples by culturing and in 29.4% of samples by PAS staining. C. albicans DNA was detected most frequently in samples from OLP patients. We conclude that, in comparison to conventional methods for detection of C. albicans, the LAMP method is highly sensitive and time-saving, and does not require expensive equipment or diagnostic technology. It may therefore be useful for on-site screening of C. albicans at dental clinics.

  9. Recovery Phenomenon During Annealing of an As-Rapidly Solidified Al Alloy

    Science.gov (United States)

    Yan, Zhigang; Mao, Shuaiying; Lin, Yaojun; Zhang, Yaqi; Wang, Limin

    2017-06-01

    It has been well documented that recovery occurring in metals/alloys produced via solid-state quenching involves only annihilation of supersaturated vacancies. Interestingly, in the present study, we observed completely different mechanisms underlying recovery during annealing of an Al-Zn-Mg-Cu (7075 Al) alloy processed via liquid-state quenching, i.e., rapid solidification (specifically melt spinning herein). The as-melt-spun alloy consists of refined grains containing tangled dislocations inside the grains. Following annealing at 393 K (120 °C) for 24 hours, refined grain structure was still retained and grain sizes essentially remained unchanged, but subgrains separated by dense dislocation walls were generated at grain interiors, with a much lower density of dislocations at subgrain interiors than that in the as-melt-spun 7075 Al alloy and dislocation arrays inside some subgrains. The microstructural evolution suggests the absence of recrystallization and the occurrence of recovery primarily via the annihilation and rearrangement of dislocations and the formation of subgrains. Based on the stored energy in dislocations in, and the annealing temperature of, the as-melt-spun 7075 Al alloy, the recovery phenomenon was analyzed and discussed in detail.

  10. Development of a loop-mediated isothermal amplification method for rapid detection of pigeon circovirus.

    Science.gov (United States)

    Tsai, Shinn Shyong; Chang, Yeng Ling; Huang, Yen Li; Liu, Hung Jen; Ke, Guan Ming; Chiou, Chwei Jang; Hsieh, Yao Ching; Chang, Tsung Chou; Cheng, Li Ting; Chuang, Kuo Pin

    2014-05-01

    There are no effective antiviral treatments for pigeon circovirus (PiCV); thus, rapid diagnosis is critical for effective control of the disease caused by this virus. The recent development of a novel LAMP technique that amplifies nucleic acids rapidly with high specificity and sensitivity under isothermal conditions has overcome some of the deficiencies of nucleic-acid-based diagnostic tests. We established a LAMP method for rapid detection of PiCV using two pairs of primers that were designed from PiCV and compared its sensitivity and specificity with that of PCR. Amplification by LAMP was optimal at 63 °C for 60 min. The detection limit was nearly 0.5 pg of PiCV DNA, making it ten times more sensitive than PCR. There was no cross-reaction with porcine circovirus type 2 (PCV2), pigeon Trichomonas gallinae, or pigeon herpesvirus (PHV) under the same conditions. The assay also successfully detected the pathogen DNA in the tissues of infected pigeons. This is the first report indicating that LAMP is a valuable, rapid method of detecting PiCV with high sensitivity and specificity.

  11. Rapid and Versatile Photonic Annealing of Graphene Inks for Flexible Printed Electronics.

    Science.gov (United States)

    Secor, Ethan B; Ahn, Bok Y; Gao, Theodore Z; Lewis, Jennifer A; Hersam, Mark C

    2015-11-01

    Intense pulsed light (IPL) annealing of graphene inks is demonstrated for rapid post-processing of inkjet-printed patterns on various substrates. A conductivity of ≈25,000 S m(-1) is achieved following a single printing pass using a concentrated ink containing 20 mg mL(-1) graphene, establishing this strategy as a practical and effective approach for the versatile and high-performance integration of graphene in printed and flexible electronics. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Fluorine implantation effects on Ta2O5 dielectrics on polysilicon treated with post rapid thermal annealing

    Science.gov (United States)

    Chen, Hsiang; Kao, Chyuan Haur; Huang, Bo Yun; Lo, Wen Shih

    2013-10-01

    This paper investigates effects of fluorine implantation with post rapid thermal annealing on electrical characteristics and material properties of tantalum pentoxide (Ta2O5) dielectrics. The electrical behaviors of the dielectrics under various implantation doses were measured. To investigate annealing effects, secondary ion mass spectrometry (SIMS) was used to measure depth profiles of various atoms inside the dielectrics with and without annealing. In addition, atomic force microscopy measurements visualize the surface roughness and material properties of the dielectrics with different implantation doses. The dielectric performance can be significantly improved by an appropriate fluorine implantation dose of 1 × 1015 ions/cm2 with post annealing at 800 °C. The improvements in electrical characteristics were caused by the appropriate incorporation of the fluorine atoms presented in SIMS profiles and the removal of the dangling bonds and traps. The Ta2O5 dielectric incorporated with appropriate fluorine implantation and annealing treatments shows great promise for future generation of memory applications.

  13. Rapid, sensitive, and specific detection of Clostridium tetani by loop-mediated isothermal amplification assay.

    Science.gov (United States)

    Jiang, Dongneng; Pu, Xiaoyun; Wu, Jiehong; Li, Meng; Liu, Ping

    2013-01-01

    Tetanus is a specific infectious disease, which is often associated with catastrophic events such as earthquakes, traumas, and war wounds. The obligate anaerobe Clostridium tetani is the pathogen that causes tetanus. Once the infection of tetanus progresses to an advanced stage within the wounds of limbs, the rates of amputation and mortality increase manifold. Therefore, it is necessary to devise a rapid and sensitive point-of-care detection method for C. tetani so as to ensure an early diagnosis and clinical treatment of tetanus. In this study, we developed a detection method for C. tetani using loop-mediated isothermal amplification (LAMP) assay, wherein the C. tetani tetanus toxin gene was used as the target gene. The method was highly specific and sensitive, with a detection limit of 10 colony forming units (CFU)/ml, and allowed quantitative analysis. While detecting C. tetani in clinical samples, it was found that the LAMP results completely agreed with those of the traditional API 20A anaerobic bacteria identification test. As compared with the traditional API test and PCR assay, LAMP detection of C. tetani is simple and rapid, and the results can be identified through naked-eye observation. Therefore, it is an ideal and rapid point-of-care testing method for tetanus.

  14. Rapid Hydrothermal Synthesis of Zinc Oxide Nanowires by Annealing Methods on Seed Layers

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    Jang Bo Shim

    2011-01-01

    Full Text Available Well-aligned zinc oxide (ZnO nanowire arrays were successfully synthesized on a glass substrate using the rapid microwave heating process. The ZnO seed layers were produced by spinning the precursor solutions onto the substrate. Among coatings, the ZnO seed layers were annealed at 100°C for 5 minutes to ensure particle adhesion to the glass surface in air, nitrogen, and vacuum atmospheres. The annealing treatment of the ZnO seed layer was most important for achieving the high quality of ZnO nanowire arrays as ZnO seed nanoparticles of larger than 30 nm in diameter evolve into ZnO nanowire arrays. Transmission electron microscopy analysis revealed a single-crystalline lattice of the ZnO nanowires. Because of their low power (140 W, low operating temperatures (90°C, easy fabrication (variable microwave sintering system, and low cost (90% cost reduction compared with gas condensation methods, high quality ZnO nanowires created with the rapid microwave heating process show great promise for use in flexible solar cells and flexible display devices.

  15. Rapid thermal annealing of YBaCuO films on Si and SiO/sub 2/ substrates

    Energy Technology Data Exchange (ETDEWEB)

    Aslam, M.; Soltis, R.E.; Logothetis, E.M.; Ager, R.; Mikkor, M.; Win, W.; Chen, J.T.; Wenger, L.E.

    1988-07-11

    A very rapid thermal annealing technique has been employed on sputter-deposited YBaCuO films. After an O/sub 2/ anneal (with or without a N/sub 2/ preanneal) at temperatures as high as 920 /sup 0/C for 8--12 s, films on (100)Si and on SiO/sub 2/ /Si substrates exhibited superconductivity onsets above 95 K and zero resistance in the range 40--66 K.

  16. Evaluation of loop-mediated isothermal amplification assay for rapid diagnosis of Acanthamoeba keratitis

    Directory of Open Access Journals (Sweden)

    Abhishek Mewara

    2017-01-01

    Full Text Available Background: The clinical features of Acanthamoeba keratitis (AK are non-specific and closely resemble bacterial, viral and fungal keratitis. Materials and Methods: We compared loop-mediated isothermal amplification (LAMP with microscopy, non-nutrient agar (NNA culture and polymerase chain reaction (PCR in clinical suspects of AK. Results: Of 52 clinical samples (42 AK suspects and 10 proven bacterial, viral or fungal keratitis, 3 were positive by direct microscopy (sensitivity 60%, confidence interval [CI]: 17%–92.7%, and 5 by NNA culture, 18S rDNA PCR and LAMP (sensitivity 100%, CI: 46.3%–100%. The limit of detection of Acanthamoeba DNA was 1 pg/μl by both LAMP and PCR. Conclusion: PCR and LAMP assays targeting 18S rDNA gene were found particularly suitable for a rapid and accurate diagnosis of AK. LAMP assay takes 2–3 h lesser than PCR, and thus offers a rapid, highly sensitive and specific, simple and affordable diagnostic modality for patients suspected of AK, especially in resource limited settings

  17. A real-time loop-mediated isothermal amplification assay for rapid detection of Shigella species.

    Science.gov (United States)

    Liew, P S; Teh, C S J; Lau, Y L; Thong, K L

    2014-12-01

    Shigellosis is a foodborne illness caused by the genus Shigella and is an important global health issue. The development of effective techniques for rapid detection of this pathogen is essential for breaking the chain of transmission. Therefore, we have developed a novel loop-mediated isothermal amplification (LAMP) assay targeting the invasion plasmid antigen H (ipaH) gene to rapidly detect Shigella species. This assay could be performed in 90 min at an optimal temperature of 64ºC, with endpoint results visualized directly. Notably, the method was found to be more sensitive than conventional PCR. Indeed, the detection limit for the LAMP assay on pure bacterial cultures was 5.9 x 10(5) CFU/ml, while PCR displayed a limit of 5.9 x 10(7) CFU/ml. In spiked lettuce samples, the sensitivity of the LAMP assay was 3.6 x 10(4) CFU/g, whereas PCR was 3.6 x 10(5) CFU/g. Overall, the assay accurately identified 32 Shigella spp. with one enteroinvasive Escherichia coli displaying positive reaction while the remaining 32 non-Shigella strains tested were negative.

  18. Detection of Bar Transgenic Sugarcane with a Rapid and Visual Loop-Mediated Isothermal Amplification Assay.

    Science.gov (United States)

    Zhou, Dinggang; Wang, Chunfeng; Li, Zhu; Chen, Yun; Gao, Shiwu; Guo, Jinlong; Lu, Wenying; Su, Yachun; Xu, Liping; Que, Youxiong

    2016-01-01

    Genetic engineering offers an attractive alternative in sugarcane breeding for increasing cane and sugar yields as well as disease and insect resistance. Bar transgenic sugarcane employing the herbicide tolerance is a useful agronomical trait in weed control. In this study, a loop-mediated isothermal amplification (LAMP) assay for rapid detection of the bar gene in transgenic sugarcane has been developed and evaluated. A set of six primers was designed for LAMP-based amplification of the bar gene. The LAMP reaction conditions were optimized as follows: 5.25 mM of Mg(2+), 6:1 ratio of inner vs. outer primer, and 6.0 U of Bst DNA polymerase in a reaction volume of 25.0 μL. The detection limit of the recombinant plasmid 1Ac0229 was as low as 10 copies in the developed LAMP, which was 10-fold higher sensitive than that of conventional PCR. In 100 putative transgenic lines, the bar gene was detected in 100/100 cases (100%) by LAMP and 97/100 cases (97%) by conventional PCR, respectively. In conclusion, the developed LAMP assay is visual, rapid, sensitive, reliable, and cost-effective for detection of the bar specific transgenic sugarcane.

  19. Detection of bar transgenic sugarcane with a rapid and visual loop-mediated isothermal amplification assay

    Directory of Open Access Journals (Sweden)

    Dinggang eZhou

    2016-03-01

    Full Text Available Genetic engineering offers an attractive alternative in sugarcane breeding for increasing cane and sugar yields as well as disease and insect resistance. Bar transgenic sugarcane employing the herbicide tolerance is a useful agronomical trait in weed control. In this study, a loop-mediated isothermal amplification (LAMP assay for rapid detection of the bar gene in transgenic sugarcane has been developed and evaluated. A set of six primers was designed for LAMP-based amplification of the bar gene. The LAMP reaction conditions were optimized as follows: 5.25 mM of Mg2+, 6:1 ratio of inner vs outer primer, and 6.0 U of Bst DNA polymerase in a reaction volume of 25.0 μL. The detection limit of the recombinant plasmid 1Ac0229 was as low as 10 copies in the developed LAMP, which was ten-fold higher sensitive than that of conventional PCR. In 100 putative transgenic lines, the bar gene was detected in 100/100 cases (100% by LAMP and 97/100 cases (97% by conventional PCR, respectively. In conclusion, the developed LAMP assay is visual, rapid, sensitive, reliable and cost-effective for detection of the bar specific transgenic sugarcane.

  20. Formation and Device Application of Ge Nanowire Heterostructures via Rapid Thermal Annealing

    Directory of Open Access Journals (Sweden)

    Jianshi Tang

    2011-01-01

    Full Text Available We reviewed the formation of Ge nanowire heterostructure and its field-effect characteristics by a controlled reaction between a single-crystalline Ge nanowire and Ni contact pads using a facile rapid thermal annealing process. Scanning electron microscopy and transmission electron microscopy demonstrated a wide temperature range of 400~500°C to convert the Ge nanowire to a single-crystalline Ni2Ge/Ge/Ni2Ge nanowire heterostructure with atomically sharp interfaces. More importantly, we studied the effect of oxide confinement during the formation of nickel germanides in a Ge nanowire. In contrast to the formation of Ni2Ge/Ge/Ni2Ge nanowire heterostructures, a segment of high-quality epitaxial NiGe was formed between Ni2Ge with the confinement of Al2O3 during annealing. A twisted epitaxial growth mode was observed in both two Ge nanowire heterostructures to accommodate the large lattice mismatch in the NixGe/Ge interface. Moreover, we have demonstrated field-effect transistors using the nickel germanide regions as source/drain contacts to the Ge nanowire channel. Our Ge nanowire transistors have shown a high-performance p-type behavior with a high on/off ratio of 105 and a field-effect hole mobility of 210 cm2/Vs, which showed a significant improvement compared with that from unreacted Ge nanowire transistors.

  1. Rapid Thermal Annealing for Solution Synthesis of Transparent Conducting Aluminum Zinc Oxide Thin Films

    Science.gov (United States)

    Ullah, Sana; De Matteis, Fabio; Davoli, Ivan

    2017-11-01

    Transparent conducting oxide films with optimized dopant molar ratio have been prepared with limited pre- and postdeposition annealing duration of 10 min. Multiple aluminum zinc oxide (AZO) layers were spin-coated on ordinary glass substrates. The predeposition consolidation temperature and dopant molar ratio were optimized for electrical conductivity and optical transparency. Next, a group of films were deposited on Corning glass substrates from precursor solutions with the optimized dopant ratio, followed by postdeposition rapid thermal annealing (RTA) at different temperatures and in controlled environments. The lowest resistivity of 10.1 × 10-3 Ω cm was obtained for films receiving RTA at 600°C for 10 min each in vacuum then in N2-5%H2 environment, while resistivity of 20.3 × 10-3 Ω cm was obtained for films subjected to RTA directly in N2-5%H2. Optical measurements revealed average total transmittance of about 85% in the visible region. A direct allowed transition bandgap was determined based on the absorption edge with a value slightly above 3.0 eV, within the typical range for semiconductors. RTA resulted in desorption of oxygen with enhanced carrier concentration and crystallinity, which increased the carrier mobility with decreased bulk resistivity while maintaining the required optical transparency.

  2. Development of Rapid Isothermal Amplification Assays for Detection of Phytophthora spp. in Plant Tissue.

    Science.gov (United States)

    Miles, Timothy D; Martin, Frank N; Coffey, Michael D

    2015-02-01

    Several isothermal amplification techniques recently have been developed that are tolerant of inhibitors present in many plant extracts, which can reduce the need for obtaining purified DNA for running diagnostic assays. One such commercially available technique that has similarities with real-time polymerase chain reaction (PCR) for designing primers and a labeled probe is recombinase polymerase amplification (RPA). This technology was used to develop two simple and rapid approaches for detection of Phytophthora spp.: one genus-specific assay multiplexed with a plant internal control and the other species-specific assays for Phytophthora ramorum and P. kernoviae. All assays were tested for sensitivity (ranging from 3 ng to 1 fg of DNA) and specificity using DNA extracted from more than 136 Phytophthora taxa, 21 Pythium spp., 1 Phytopythium sp., and a wide range of plant species. The lower limit of linear detection using purified DNA was 200 to 300 fg of DNA in all pathogen RPA assays. Six different extraction buffers were tested for use during plant tissue maceration and the assays were validated in the field by collecting 222 symptomatic plant samples from over 50 different hosts. Only 56 samples were culture positive for Phytophthora spp. whereas 91 were positive using the Phytophthora genus-specific RPA test and a TaqMan real-time PCR assay. A technique for the generation of sequencing templates from positive RPA amplifications to confirm species identification was also developed. These RPA assays have added benefits over traditional technologies because they are rapid (results can be obtained in as little as 15 min), do not require DNA extraction or extensive training to complete, use less expensive portable equipment than PCR-based assays, and are significantly more specific than current immunologically based methods. This should provide a rapid, field-deployable capability for pathogen detection that will facilitate point-of-sample collection processing

  3. Phase selection and nanocrystallization in Cu-free soft magnetic FeSiNbB amorphous alloy upon rapid annealing

    Energy Technology Data Exchange (ETDEWEB)

    Morsdorf, L.; Povstugar, I.; Raabe, D. [Department for Microstructure Physics and Alloy Design, Max-Planck-Institut für Eisenforschung GmbH, Max-Planck-Str. 1, 40237 Düsseldorf (Germany); Pradeep, K. G., E-mail: kg.prad@mpie.de, E-mail: kgprad@gmail.com [Department for Microstructure Physics and Alloy Design, Max-Planck-Institut für Eisenforschung GmbH, Max-Planck-Str. 1, 40237 Düsseldorf (Germany); Materials Chemistry, RWTH Aachen University, Kopernikusstrasse 10, 52074 Aachen (Germany); Herzer, G. [Vacuumschmelze GmbH & Co KG, Grüner Weg 37, D-63450 Hanau (Germany); Kovács, A.; Dunin-Borkowski, R. E. [Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons and Peter Grünberg Institute 5, Forschungszentrum Jülich, 52425 Jülich (Germany); Konygin, G. [Physical-Technical Institute UrB RAS, Kirov str. 132, 426008 Izhevsk (Russian Federation); Choi, P. [Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology, Daejeon 34141 (Korea, Republic of)

    2016-03-28

    Nucleation of soft magnetic Fe{sub 3}Si nanocrystals in Cu-free Fe{sub 74.5}Si{sub 15.5}Nb{sub 3}B{sub 7} alloy, upon rapid (10 s) and conventional (30 min) annealing, was investigated using x-ray diffraction, transmission electron microscopy, Mössbauer spectroscopy, and atom probe tomography. By employing rapid annealing, preferential nucleation of Fe{sub 3}Si nanocrystals was achieved, whereas otherwise there is simultaneous nucleation of both Fe{sub 3}Si and undesired Fe-B compound phases. Analysis revealed that the enhanced Nb diffusivity, achieved during rapid annealing, facilitates homogeneous nucleation of Fe{sub 3}Si nanocrystals while shifting the secondary Fe-B crystallization to higher temperatures resulting in pure soft magnetic nanocrystallization with very low coercivities of ∼10 A/m.

  4. Optical characteristics of GaAsSb alloy after rapid thermal annealing

    Science.gov (United States)

    Gao, Xian; Zhao, Fenghuan; Fang, Xuan; Tang, Jilong; Fang, Dan; Wang, Dengkui; Wang, Xiaohua; Wei, Zhipeng; Chen, Rui

    2017-11-01

    GaAsSb ternary alloy is a promising material for application in infrared optoelectronic devices. In this letter, the investigation of carrier recombination in the as-grown and rapid thermal annealing (RTA) treated GaAsSb samples has been carried out. It was found that after thermal treatment the emission of the GaAsSb material was enhanced and could be maintained up to room temperature. These phenomena can be ascribed to the decrease of non-radiative combination defects in the GaAsSb sample, which implies an improved crystal quality. Moreover, the localized exciton-longitudinal optical phonon interaction is slightly increased after RTA treatment. It is suggested that the interaction depends strongly on the localized states, and the photoluminescence emission intensity can be significantly increased after suitable RTA treatment. Promoting better optical emission in GaAsSb is very useful for its practical application.

  5. Development of loop-mediated isothermal amplification for rapid detection of Entamoeba histolytica.

    Science.gov (United States)

    Rivera, Windell L; Ong, Vanissa A

    2013-06-01

    To develop a loop-mediated isothermal amplification (LAMP) assay for the detection of Entamoeba histolytica E. histolytica, the causative agent of amebiasis. The LAMP primer set was designed from E. histolytica hemolysin gene HLY6. Genomic DNA of E. histolytica trophozoites strain HK9 was used to optimize the LAMP mixture and conditions. Amplification of DNA in the LAMP mixture was monitored through visual inspection for turbidity of the LAMP mix as well as addition of fluorescent dye. Positive LAMP reactions turned turbid while negative ones remained clear. Upon addition of a fluorescent dye, all positive reactions turned green while the negative control remained orange under ambient light. After electrophoresis in 1.5% agarose gels, a ladder of multiple bands of different sizes can be observed in positive samples while no bands were detected in the negative control. The sensitivity of the assay was found to be 5 parasites per reaction which corresponds to approximately 15.8 ng/μ L DNA. The specificity of the assay was verified by the absence of amplified products when DNA from other gastrointestinal parasites such as the morphologically similar but non-pathogenic species, Entamoeba dispar 39, and other diarrhea-causing organisms such as Blastocystis hominis and Escherichia coli were used. The LAMP assay we have developed enables the detection of E. histolytica with rapidity and ease, therefore rendering it is suitable for laboratory and field diagnosis of amebiasis. Copyright © 2013 Hainan Medical College. Published by Elsevier B.V. All rights reserved.

  6. Rapid detection of Brucella spp. using loop-mediated isothermal amplification (LAMP).

    Science.gov (United States)

    Chen, Shouyi; Li, Xunde; Li, Juntao; Atwill, Edward R

    2013-01-01

    Brucella spp. are facultative intracellular bacteria that cause zoonotic disease of brucellosis worldwide. Livestock that are most vulnerable to brucellosis include cattle, goats, and pigs. Brucella spp. cause serious health problems to humans and animals and economic losses to the livestock industry. Traditional methods for detection of Brucella spp. take 48-72 h (Kumar et al., J Commun Dis 29:131-137, 1997; Barrouin-Melo et al., Res Vet Sci 83:340-346, 2007) that do not meet the food industry's need of rapid detection. Therefore, there is an urgent need of fast, specific, sensitive, and inexpensive method for diagnosing of Brucella spp. Loop-mediated isothermal amplification (LAMP) is a method to amplify nucleic acid at constant temperatures. Amplification can be detected by visual detection, fluorescent stain, turbidity, and electrophoresis. We targeted at the Brucella-specific gene omp25 and designed LAMP primers for detection of Brucella spp. Amplification of DNA with Bst DNA polymerase can be completed at 65 °C in 60 min. Amplified products can be detected by SYBR Green I stain and 2.0% agarose gel electrophoresis. The LAMP method is feasible for detection of Brucella spp. from blood and milk samples.

  7. Loop-Mediated Isothermal Amplification Assay for the Rapid Detection of Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    King Ting Lim

    2013-01-01

    Full Text Available Staphylococcus aureus, including methicillin-resistant S. aureus (MRSA, is an important human pathogen that produces a variety of toxins and causes a wide range of infections, including soft-tissue infections, bacteremia, and staphylococcal food poisoning. A loop-mediated isothermal amplification (LAMP assay targeting the arcC gene of S. aureus was developed and evaluated with 119 S. aureus and 25 non-S. aureus strains. The usefulness of the assay was compared with the PCR method that targets spa and arcC genes. The optimal temperature for the LAMP assay was 58.5°C with a detection limit of 2.5 ng/μL and 102 CFU/mL when compared to 12.5 ng/μL and 103 CFU/mL for PCR (spa and arcC. Both LAMP and PCR assays were 100% specific, 100% sensitive, 100% positive predictive value (PPV, and 100% negative predictive value (NPV. When tested on 30 spiked blood specimens (21 MRSA, eight non-S. aureus and one negative control, the performance of LAMP and PCR was comparable: 100% specific, 100% sensitive, 100% PPV, and 100% NPV. In conclusion, the LAMP assay was equally specific with a shorter detection time when compared to PCR in the identification of S. aureus. The LAMP assay is a promising alternative method for the rapid identification of S. aureus and could be used in resource-limited laboratories and fields.

  8. Rapid detection of equine coronavirus by reverse transcription loop-mediated isothermal amplification.

    Science.gov (United States)

    Nemoto, Manabu; Morita, Yoshinori; Niwa, Hidekazu; Bannai, Hiroshi; Tsujimura, Koji; Yamanaka, Takashi; Kondo, Takashi

    2015-04-01

    A reverse transcription loop-mediated isothermal amplification (RT-LAMP) assay was developed for the rapid detection of equine coronavirus (ECoV). This assay was conducted at 60 °C for 40 min. Specificity of the RT-LAMP assay was confirmed using several equine intestinal and respiratory pathogens in addition to ECoV. The novel assay failed to cross-react with the other pathogens tested, suggesting it is highly specific for ECoV. Using artificially synthesized ECoV RNA, the 50% detection limit of the RT-LAMP assay was 10(1.8)copies/reaction. This is a 50-fold greater sensitivity than conventional reverse transcription polymerase chain reaction (RT-PCR) assays, but a 4-fold lower sensitivity than quantitative RT-PCR (qRT-PCR) assays. Eighty-two fecal samples collected during ECoV outbreaks were analyzed. ECoV was detected in 59 samples using the RT-LAMP assay, and in 30 and 65 samples using RT-PCR or qRT-PCR assays, respectively. Although the RT-LAMP assay is less sensitive than qRT-PCR techniques, it can be performed without the need for expensive equipment. Thus, the RT-LAMP assay might be suitable for large-scale surveillance and diagnosis of ECoV infection in laboratories with limited resources. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. Rapid, Loop-Mediated Isothermal Amplification Detection of Coeliac Disease Risk Alleles.

    Science.gov (United States)

    Erlichster, Michael; Tye-Din, Jason A; Varney, Michael D; Skafidas, Efstratios; Kwan, Patrick

    2018-02-16

    Human leukocyte antigen (HLA) genotyping has become a useful investigation in the diagnostic work-up of coeliac disease (CD), with utility in risk stratification and screening. However, broad application of this technology has been hindered by the cost and time burden of conventional laboratory-based assays. We have developed and validated CD-loop-mediated isothermal amplification (CD-LAMP), a LAMP assay, which enables rapid identification of the signature CD risk genotypes, HLA-DQ2.5, HLA-DQ8, HLA-DQ2.2, and HLA-DQA1*05. Sample-to-answer is achieved in approximately 65 minutes without DNA purification, thermal cycling, or specialized analytical equipment. CD-LAMP genotyping of samples was 100% concordant with accredited pathology genotyping on a panel of 40 blood and 20 saliva samples. In a panel of 100 purified DNA samples, genotyping of the high risk DQ2.5 genotype was 100% concordant with accredited pathology genotyping, with slightly reduced sensitivity for the DQ8 genotype (97.1%), and reduced specificity for the DQ8 (93.9%) and DQ2.2 genotypes (95.1%). CD-LAMP results are easily visualized, instrument free, through the addition of a DNA intercalating dye following amplification. Combined with point-of-care antibody testing, CD-LAMP may enable immediate, confident CD diagnosis at a low cost in the clinical setting. Copyright © 2018. Published by Elsevier Inc.

  10. Rapid detection of microbial DNA by a novel isothermal genome exponential amplification reaction (GEAR) assay.

    Science.gov (United States)

    Prithiviraj, Jothikumar; Hill, Vincent; Jothikumar, Narayanan

    2012-04-20

    In this study we report the development of a simple target-specific isothermal nucleic acid amplification technique, termed genome exponential amplification reaction (GEAR). Escherichia coli was selected as the microbial target to demonstrate the GEAR technique as a proof of concept. The GEAR technique uses a set of four primers; in the present study these primers targeted 5 regions on the 16S rRNA gene of E. coli. The outer forward and reverse Tab primer sequences are complementary to each other at their 5' end, whereas their 3' end sequences are complementary to their respective target nucleic acid sequences. The GEAR assay was performed at a constant temperature 60 °C and monitored continuously in a real-time PCR instrument in the presence of an intercalating dye (SYTO 9). The GEAR assay enabled amplification of as few as one colony forming units of E. coli per reaction within 30 min. We also evaluated the GEAR assay for rapid identification of bacterial colonies cultured on agar media directly in the reaction without DNA extraction. Cells from E. coli colonies were picked and added directly to GEAR assay mastermix without prior DNA extraction. DNA in the cells could be amplified, yielding positive results within 15 min. Published by Elsevier Inc.

  11. Effect of two-stage isothermal annealing on microstructure CuAl10Fe5Ni5 bronze with additions of Si, Cr, Mo, W and C

    Directory of Open Access Journals (Sweden)

    B. P. Pisarek

    2011-07-01

    Full Text Available The aim of this study was to investigate the effect of a two-step isothermal annealing respectively at 1000 ̊C for 30 min, then at the range of 900÷450 ̊C increments 50 ̊C on the microstructure CuAl10 Ni5Fe5 bronze with additions of Si, Cr, Mo, W and C, cast into sand moulds. The study concerned the newly developed species, bronze, aluminium-iron-nickel with additions of Si, Cr, Mo, W and C. In order to determine the time and temperature for the characteristic of phase transitions that occur during heat treatment of the test method was used thermal and derivation analysis (TDA. The study was conducted on cylindrical test castings cast in the mould of moulding sand. It was affirmed that one the method TDA can appoint characteristic for phase transformations points about co-ordinates: τ (s, t ( ̊ C, and to plot out curves TTT for the studied bronze with their use. It was also found that there is a fiveisothermalannealingtemperatureranges significantly altering the microstructure of examined bronze.

  12. Development of a loop-mediated isothermal amplification assay for rapid detection of capripoxviruses.

    Science.gov (United States)

    Das, Amaresh; Babiuk, Shawn; McIntosh, Michael T

    2012-05-01

    Sheep pox (SP), goat pox (GP), and lumpy skin disease (LSD), caused by capripoxviruses (CaPVs), are economically important diseases of sheep, goats, and cattle, respectively. Here, we report the development of a loop-mediated isothermal amplification (LAMP) assay for rapid detection of CaPVs. LAMP primers were designed to target a conserved gene encoding the poly(A) polymerase small subunit (VP39) of CaPVs. Hydroxynaphthol blue (HNB) was incorporated to monitor assay progress by color change from violet when negative to sky blue when positive, and results were verified by agarose gel electrophoresis. The LAMP assay was shown to be highly specific for CaPVs, with no apparent cross-reactivity to other related viruses (near neighbors) or viruses that cause similar clinical signs (look-a-like viruses). The performance of LAMP was compared to that of a highly sensitive quantitative real-time PCR (qPCR) assay. LAMP and qPCR exhibited similar analytical sensitivities, with limits of detection of 3 and 8 viral genome copies, respectively. Diagnostic specificity was assessed on 36 negative specimens, including swabs and EDTA blood from control sheep, goats, and cattle. Diagnostic sensitivity was assessed on 275 specimens, including EDTA blood, swabs, and tissues from experimentally infected sheep, goats, and cattle. Overall agreement on diagnostic test results between the two assays was 90 to 95% for specificity and 89 to 100% for sensitivity. The LAMP assay described in this report is simple to use, inexpensive, highly sensitive, and particularly well suited for the diagnosis of capripox in less well equipped laboratories and in rural settings where resources are limited.

  13. Characterization of a rapid thermal anneal TiNxOy/TiSi2 contact barrier

    Science.gov (United States)

    Ho, V. Q.

    1989-07-01

    In this paper, the physical and electrical properties of a TiNxOy/TiSi2 dual layer contact barrier are reported. The TiNxOy/TiSi2 barrier was formed by rapidly annealing a Ti thin film on Si in an N2 ambient. During this process, the Ti film surface reacts with N2 to form a TiNxOy skin layer and the bulk of the Ti film reacts with Si to form an underlying TiSi2 layer. The influences of rapid thermal anneal (RTA) conditions on the TiNxOy layer were investigated by varying the RTA temperature from 600 to 1100° C and cycle duration from 30 to 100 s. It is found that the resulting TiNxOy and TiSi2 layer thicknesses are dependent on RTA temperature and the starting Ti thickness. For a starting Ti thickness of 500Å, 150Å thick TiNxOy and 800Å thick TiSi2 are obtained after an RTA at 900° C for 30 s. The TiNxOy thickness is limited by a fast diffusion of Si into Ti to form TiSi2. When a Ti film is deposited on SiO2, Ti starts to react with SiO2 from 600° C and a significant reduction of the SiO2 thickness is observed after an RTA at 900° C. The resulting layer is composed of a surface TiNxOy layer followed by a complex layer of titanium oxide and titanium suicide. In addition, when Ti is depos-ited on TiSi2, thicker TiNxOy and TiSi2 layers are obtained after RTA. This is because the TiSi2 layer retards the diffusion of Si from the underlying substrate into the Ti layer. NMOSFETs were fabricated using the TiNxOy/TiSi2 as a contact barrier formed by RTA at 900° C for 30 s and a significant reduction of contact resistance was obtained. In addition, electromigration test at a high current density indicated that a significant improvement in mean time to failure (MTF) has been obtained with the barrier.

  14. Effect of annealing procedure on the bonding of ceramic to cobalt-chromium alloys fabricated by rapid prototyping.

    Science.gov (United States)

    Tulga, Ayca

    2017-08-22

    An annealing procedure is a heat treatment process to improve the mechanical properties of cobalt-chromium (Co-Cr) alloys. However, information is lacking about the effect of the annealing process on the bonding ability of ceramic to Co-Cr alloys fabricated by rapid prototyping. The purpose of this in vitro study was to evaluate the effects of the fabrication techniques and the annealing procedure on the shear bond strength of ceramic to Co-Cr alloys fabricated by different techniques. Ninety-six cylindrical specimens (10-mm diameter, 10-mm height) made of Co-Cr alloy were prepared by casting (C), milling (M), direct process powder-bed (LaserCUSING) with and without annealing (CL+, CL), and direct metal laser sintering (DMLS) with annealing (EL+) and without annealing (EL). After the application of ceramic to the metal specimens, the metal-ceramic bond strength was assessed using a shear force test at a crosshead speed of 0.5 mm/min. Shear bond strength values were statistically analyzed by 1-way ANOVA and Tukey multiple comparison tests (α=.05). Although statistically significant differences were found among the 3 groups (M, 29.87 ±2.06; EL, 38.92 ±2.04; and CL+, 40.93 ±2.21; P=.002), no significant differences were found among the others (P>.05). The debonding surfaces of all specimens exhibited mixed failure mode. These results showed that the direct process powder-bed method is promising in terms of metal-ceramic bonding ability. The manufacturing technique of Co-Cr alloys and the annealing process influence metal-ceramic bonding. Copyright © 2017 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  15. Effect of Water Vapor, Temperature, and Rapid Annealing on Formamidinium Lead Triiodide Perovskite Crystallization

    Energy Technology Data Exchange (ETDEWEB)

    Aguiar, Jeffery A.; Wozny, Sarah; Alkurd, Nooraldeen R.; Yang, Mengjin; Kovarik, Libor; Holesinger, Terry G.; Al-Jassim, Mowafak; Zhu, Kai; Zhou, Weilie; Berry, Joseph J.

    2016-07-08

    Perovskite-based solar cells are one of the emerging candidates for radically lower cost photovoltaics. Herein, we report on the synthesis and crystallization of organic-inorganic formamidinium lead triiodide perovskite films under controlled atmospheric and environmental conditions. Using in situ (scanning) transmission electron microscopy, we make observations of the crystallization process of these materials in nitrogen and oxygen gas with and without the presence of water vapor. Complementary planar samples were also fabricated in the presence of water vapor and characterized by in situ X-ray diffraction. Direct observations of the material structure and final morphology indicate that the exposure to water vapor results in a porous film that is metastable, regardless of the presence of argon, nitrogen, or oxygen. However, the optimal crystallization temperature of 175 degrees C is unperturbed across conditions. Rapid modulation about the annealing temperature of 175 degrees C in +/-25 degrees C steps (150-200 degrees C) promotes crystallization and significantly improves the film morphology by overcoming the presence of impregnated water trapped in the material. Following this processing protocol, we demonstrate substantial growth to micron-size grains via observation inside of an environmentally controlled transmission electron microscope. Adapting this insight from our in situ microscopy, we are able to provide an informed materials protocol to control the structure and morphology of these organic-inorganic semiconductors, which is readily applicable to benchtop device growth strategies.

  16. Effect of Water Vapor, Temperature, and Rapid Annealing on Formamidinium Lead Triiodide Perovskite Crystallization

    Energy Technology Data Exchange (ETDEWEB)

    Aguiar, Jeffery A.; Wozny, Sarah; Alkurd, Nooraldeen R.; Yang, Mengjin; Kovarik, Libor; Holesinger, Terry; Al-Jassim, Mowafak M.; Zhu, Kai; Zhou, Weilie; Berry, J. J.

    2016-07-08

    Perovskite-based solar cells are one of the emerging candidates for radically lower cost photovoltaics. Herein, we report on the synthesis and crystallization of organic-inorganic formamidinium lead triiodide perovskite films under controlled atmospheric and environmental conditions. Using in situ (scanning) transmission electron microscopy, we make observations of the crystallization process of these materials in nitrogen and oxygen gas with and without the presence of water vapor. Complementary planar samples were also fabricated in the presence of water vapor and characterized by in situ X-ray diffraction. Direct observations of the material structure and final morphology indicate that the exposure to water vapor results in a porous film that is metastable, regardless of the presence of argon, nitrogen, or oxygen. However, the optimal crystallization temperature of 175 °C is unperturbed across conditions. Rapid modulation about the annealing temperature of 175 °C in ±25 °C steps (150-200 °C) promotes crystallization and significantly improves the film morphology by overcoming the presence of impregnated water trapped in the material. Following this processing protocol, we demonstrate substantial growth to micron-size grains via observation inside of an environmentally controlled transmission electron microscope. Adapting this insight from our in situ microscopy, we are able to provide an informed materials protocol to control the structure and morphology of these organic-inorganic semiconductors, which is readily applicable to benchtop device growth strategies.

  17. Activated Carbon Fibers "Thickly Overgrown" by Ag Nanohair Through Self-Assembly and Rapid Thermal Annealing

    Science.gov (United States)

    Yan, Xuefeng; Xu, Sijun; Wang, Qiang; Fan, Xuerong

    2017-11-01

    Anisotropic nanomaterial-modified carbon fibers attract increasing attention because of their superior properties over traditional ones. In this study, activated carbon fibers (ACFs) "thickly overgrown" by Ag nanohair were prepared through self-assembly and rapid thermal annealing. Viscose fibers with well-dispersed silver nanoparticles (AgNPs) on surfaces were first prepared through self-assembly of hyperbranched poly(amino-amine) (HBPAA)-capped AgNPs on viscose surfaces. HBPAA endowed the AgNP surfaces with negative charges and abundant amino groups, allowing AgNPs to monodispersively self-assemble to fiber surfaces. Ag nanohair-grown ACFs were prepared by sequential pre-oxidation and carbonization. Because the carbonization furnace was open-ended, ACFs are immediately transferrable to the outside of the furnace. Therefore, the Ag liquid adsorbed by ACF pores squeezed out to form Ag nanowires through thermal contraction. FESEM characterization indicated that Ag nanohairs stood on ACF surface and grew from ACF caps. XPS and XRD characterization showed that Ag successfully assembled to fiber surfaces and retained its metallic state even after high-temperature carbonization. TG analysis suggested that Ag nanohair-grown ACFs maintained their excellent thermal stabilities. Finally, the fabricated ACFs showed excellent and durable antibacterial activities, and the developed method may provide a potential strategy for preparing metal nanowire-grown ACFs.

  18. Activated Carbon Fibers "Thickly Overgrown" by Ag Nanohair Through Self-Assembly and Rapid Thermal Annealing.

    Science.gov (United States)

    Yan, Xuefeng; Xu, Sijun; Wang, Qiang; Fan, Xuerong

    2017-11-09

    Anisotropic nanomaterial-modified carbon fibers attract increasing attention because of their superior properties over traditional ones. In this study, activated carbon fibers (ACFs) "thickly overgrown" by Ag nanohair were prepared through self-assembly and rapid thermal annealing. Viscose fibers with well-dispersed silver nanoparticles (AgNPs) on surfaces were first prepared through self-assembly of hyperbranched poly(amino-amine) (HBPAA)-capped AgNPs on viscose surfaces. HBPAA endowed the AgNP surfaces with negative charges and abundant amino groups, allowing AgNPs to monodispersively self-assemble to fiber surfaces. Ag nanohair-grown ACFs were prepared by sequential pre-oxidation and carbonization. Because the carbonization furnace was open-ended, ACFs are immediately transferrable to the outside of the furnace. Therefore, the Ag liquid adsorbed by ACF pores squeezed out to form Ag nanowires through thermal contraction. FESEM characterization indicated that Ag nanohairs stood on ACF surface and grew from ACF caps. XPS and XRD characterization showed that Ag successfully assembled to fiber surfaces and retained its metallic state even after high-temperature carbonization. TG analysis suggested that Ag nanohair-grown ACFs maintained their excellent thermal stabilities. Finally, the fabricated ACFs showed excellent and durable antibacterial activities, and the developed method may provide a potential strategy for preparing metal nanowire-grown ACFs.

  19. Rapid and Sensitive Identification of the Herbal Tea Ingredient Taraxacum formosanum Using Loop-Mediated Isothermal Amplification

    Directory of Open Access Journals (Sweden)

    Guan-Hua Lai

    2015-01-01

    Full Text Available Taraxacum formosanum (TF is a medicinal plant used as an important component of health drinks in Taiwan. In this study, a rapid, sensitive and specific loop-mediated isothermal amplification (LAMP assay for authenticating TF was established. A set of four specific LAMP primers was designed based on the nucleotide sequence of the internal transcribed spacer 2 (ITS2 nuclear ribosomal DNA (nrDNA of TF. LAMP amplicons were successfully amplified and detected when purified genomic DNA of TF was added in the LAMP reaction under isothermal condition (65 °C within 45 min. These specific LAMP primers have high specificity and can accurately discriminate Taraxacum formosanum from other adulterant plants; 1 pg of genomic DNA was determined to be the detection limit of the LAMP assay. In conclusion, using this novel approach, TF and its misused plant samples obtained from herbal tea markets were easily identified and discriminated by LAMP assay for quality control.

  20. Interdiffusion and growth of chromium silicide at the interface of Cr/Si(As) system during rapid thermal annealing

    Energy Technology Data Exchange (ETDEWEB)

    Benkherbache, H. [Universite de M' Sila, (28000) M' Sila (Algeria); Merabet, A., E-mail: merabet_abdelali@yahoo.f [Laboratoire Physique et Mecanique des Materiaux Metalliques, Departement d' O.M.P., Faculte des Sciences de l' Ingenieur, Universite de Setif, (19000) Setif (Algeria)

    2010-02-26

    In this work, the solid-state reaction between a thin film of chromium and silicon has been studied using Rutherford backscattering spectroscopy, X-ray diffraction and the sheet resistance measurements. The thickness of 100 nm chromium layer has been deposited by electronic bombardment on Si (100) substrates, part of them had previously been implanted with arsenic ions of 10{sup 15} at/cm{sup 2} doses and an energy of 100 keV. The samples were heat treated under rapid thermal annealing at 500 {sup o}C for time intervals ranging from 15 to 60 s. The rapid thermal annealing leads to a reaction at the interface Cr/Si inducing the formation and the growth of the unique silicide CrSi{sub 2}, but no other phase can be detected. For samples implanted with arsenic, the saturation value of the sheet resistance is approximately 1.5 times higher than for the non-implanted case.

  1. Manipulating the adhesion of electroless nickel-phosphorus film on silicon wafers by silane compound modification and rapid thermal annealing

    OpenAIRE

    Hsu, Chin-Wei; Wang, Wei-Yen; Wang, Kuan-Ting; Chen, Hou-An; Wei, Tzu-Chien

    2017-01-01

    In this study, the effect of 3-2-(2-aminoethylamino) ethylamino propyl trimethoxysilane (ETAS) modification and post rapid thermal annealing (RTA) treatment on the adhesion of electroless plated nickel-phosphorus (ELP Ni-P) film on polyvinyl alcohol-capped palladium nanoclusters (PVA-Pd) catalyzed silicon wafers is systematically investigated. Characterized by pull-off adhesion, atomic force microscopy, X-ray spectroscopy and water contact angle, a time-dependent, three-staged ETAS grafting m...

  2. Development and evaluation of loop-mediated isothermal amplification assay for rapid detection of Capripoxvirus

    OpenAIRE

    Kanisht Batra; Aman Kumar; Vinay Kumar; Trilok Nanda; Maan, Narender S.; Sushila Maan

    2015-01-01

    Aim: The present study was undertaken to develop a nucleic acid-based diagnostic assay loop-mediated isothermal amplification assay (LAMP) targeting highly conserved genomic regions of Capripoxvirus (CaPVs) and its comparative evaluation with real-time polymerase chain reaction (PCR). Material and Methods: Lyophilized vaccine strain of sheeppox virus (SPPV) was used for optimization of LAMP assay. The LAMP assay was designed using envelope immunogenic protein (P32) coding gene targeting highl...

  3. Rapid thermal annealing of sputter-deposited ZnO:Al films for microcrystalline Si thin-film solar cells

    Directory of Open Access Journals (Sweden)

    Hanajiri T.

    2012-06-01

    Full Text Available Rapid thermal annealing of sputter-deposited ZnO and Al-doped ZnO (AZO films with and without an amorphous silicon (a-Si capping layer was investigated using a radio-frequency (rf argon thermal plasma jet of argon at atmospheric pressure. The resistivity of bare ZnO films on glass decreased from 108 to 104–105 Ω cm at maximum surface temperatures Tmaxs above 650 °C, whereas the resistivity increased from 10-4 to 10-3–10-2Ω cm for bare AZO films. On the other hand, the resistivity of AZO films with a 30-nm-thick a-Si capping layer remained below 10-4Ω cm, even after TPJ annealing at a Tmax of 825 °C. The film crystallization of both AZO and a-Si layers was promoted without the formation of an intermixing layer. Additionally, the crystallization of phosphorous- and boron-doped a-Si layers at the sample surface was promoted, compared to that of intrinsic a-Si under the identical plasma annealing conditions. The TPJ annealing of n+-a-Si/textured AZO was applied for single junction n-i-p microcrystalline Si thin-film solar cells.

  4. Improvement and Evaluation of Loop-Mediated Isothermal Amplification for Rapid Detection of Toxoplasma gondii Infection in Human Blood Samples.

    Directory of Open Access Journals (Sweden)

    Xi-Meng Sun

    Full Text Available Loop-mediated isothermal amplification (LAMP, an attractive DNA amplification method, was developed as a valuable tool for the rapid detection of Toxoplasma gondii. In this study, species-specific LAMP primers were designed by targeting the AF146527 sequence, which was a conserved sequence of 200- to 300-fold repetitive 529 bp fragment of T.gondii. LAMP reaction system was optimized so that it could detect the minimal DNA sample such as a single tachyzoite or 10 copies of recombinant plasmid. No cross-reactivity was found when using DNA from other parasites as templates. Subsequently, a total of 200 human blood samples were directly investigated by two diagnostic methods, LAMP and conventional PCR. Fourteen of 200 (7% samples were positive for Toxoplasma by LAMP (the primers developed in this study, whereas only 5 of 200 (2.5% were proved positive by conventional PCR. The procedure of the LAMP assay was very simple, as the reaction would be carried out in a single tube under isothermal conditions at 64°C and the result would be read out with 1 h (as early as 35 min with loop primers. Thus, this method has the advantages of rapid amplification, simple operation, and easy detection and would be useful for rapid and reliable clinical diagnosis of acute toxoplasmosis, especially in developing countries.

  5. Rapid Salmonella detection using an acoustic wave device combined with the RCA isothermal DNA amplification method

    Directory of Open Access Journals (Sweden)

    Antonis Kordas

    2016-12-01

    Full Text Available Salmonella enterica serovar Typhimurium is a major foodborne pathogen that causes Salmonellosis, posing a serious threat for public health and economy; thus, the development of fast and sensitive methods is of paramount importance for food quality control and safety management. In the current work, we are presenting a new approach where an isothermal amplification method is combined with an acoustic wave device for the development of a label free assay for bacteria detection. Specifically, our method utilizes a Love wave biosensor based on a Surface Acoustic Wave (SAW device combined with the isothermal Rolling Circle Amplification (RCA method; various protocols were tested regarding the DNA amplification and detection, including off-chip amplification at two different temperatures (30 °C and room temperature followed by acoustic detection and on-chip amplification and detection at room temperature, with the current detection limit being as little as 100 Bacteria Cell Equivalents (BCE/sample. Our acoustic results showed that the acoustic ratio, i.e., the amplitude over phase change observed during DNA binding, provided the only sensitive means for product detection while the measurement of amplitude or phase alone could not discriminate positive from negative samples. The method's fast analysis time together with other inherent advantages i.e., portability, potential for multi-analysis, lower sample volumes and reduced power consumption, hold great promise for employing the developed assay in a Lab on Chip (LoC platform for the integrated analysis of Salmonella in food samples.

  6. Sensitive and rapid detection of Giardia lamblia infection in pet dogs using loop-mediated isothermal amplification.

    Science.gov (United States)

    Li, Jie; Wang, Peiyuan; Zhang, Aiguo; Zhang, Ping; Alsarakibi, Muhamd; Li, Guoqing

    2013-04-01

    Giardia lamblia is recognized as one of the most prevalent parasites in dogs. The present study aimed to establish a loop-mediated isothermal amplification (LAMP) assay for rapid and specific detection of G. lamblia from dogs. The fecal samples were collected and prepared for microscopic analysis, and then the genomic DNA was extracted directly from purified cysts. The concentration of DNA samples of G. lamblia were diluted by 10-fold serially ranging from 10(-1) to 10(-5) ng/µl for LAMP and PCR assays. The LAMP assay allows the amplification to be finished within 60 min under isothermal conditions of 63℃ by employing 6 oligonucleotide primers designed based on G. lamblia elongation factor 1 alpha (EF1α) gene sequence. Our tests showed that the specific amplification products were obtained only with G. lamblia, while no amplification products were detected with DNA of other related protozoans. Sensitivity evaluation indicated that the LAMP assay was sensitive 10 times more than PCR. It is concluded that LAMP is a rapid, highly sensitive and specific DNA amplification technique for detection of G. lamblia, which has implications for effective control and prevention of giardiasis.

  7. Controlling Growth High Uniformity Indium Selenide (In2Se3) Nanowires via the Rapid Thermal Annealing Process at Low Temperature.

    Science.gov (United States)

    Hsu, Ya-Chu; Hung, Yu-Chen; Wang, Chiu-Yen

    2017-09-15

    High uniformity Au-catalyzed indium selenide (In2Se3) nanowires are grown with the rapid thermal annealing (RTA) treatment via the vapor-liquid-solid (VLS) mechanism. The diameters of Au-catalyzed In2Se3 nanowires could be controlled with varied thicknesses of Au films, and the uniformity of nanowires is improved via a fast pre-annealing rate, 100 °C/s. Comparing with the slower heating rate, 0.1 °C/s, the average diameters and distributions (standard deviation, SD) of In2Se3 nanowires with and without the RTA process are 97.14 ± 22.95 nm (23.63%) and 119.06 ± 48.75 nm (40.95%), respectively. The in situ annealing TEM is used to study the effect of heating rate on the formation of Au nanoparticles from the as-deposited Au film. The results demonstrate that the average diameters and distributions of Au nanoparticles with and without the RTA process are 19.84 ± 5.96 nm (30.00%) and about 22.06 ± 9.00 nm (40.80%), respectively. It proves that the diameter size, distribution, and uniformity of Au-catalyzed In2Se3 nanowires are reduced and improved via the RTA pre-treated. The systemic study could help to control the size distribution of other nanomaterials through tuning the annealing rate, temperatures of precursor, and growth substrate to control the size distribution of other nanomaterials. Graphical Abstract Rapid thermal annealing (RTA) process proved that it can uniform the size distribution of Au nanoparticles, and then it can be used to grow the high uniformity Au-catalyzed In2Se3 nanowires via the vapor-liquid-solid (VLS) mechanism. Comparing with the general growth condition, the heating rate is slow, 0.1 °C/s, and the growth temperature is a relatively high growth temperature, > 650 °C. RTA pre-treated growth substrate can form smaller and uniform Au nanoparticles to react with the In2Se3 vapor and produce the high uniformity In2Se3 nanowires. The in situ annealing TEM is used to realize the effect of heating rate on Au nanoparticle

  8. Rapid detection of Plasmodium falciparum with isothermal recombinase polymerase amplification and lateral flow analysis

    Science.gov (United States)

    2014-01-01

    Background Nucleic acid amplification is the most sensitive and specific method to detect Plasmodium falciparum. However the polymerase chain reaction remains laboratory-based and has to be conducted by trained personnel. Furthermore, the power dependency for the thermocycling process and the costly equipment necessary for the read-out are difficult to cover in resource-limited settings. This study aims to develop and evaluate a combination of isothermal nucleic acid amplification and simple lateral flow dipstick detection of the malaria parasite for point-of-care testing. Methods A specific fragment of the 18S rRNA gene of P. falciparum was amplified in 10 min at a constant 38°C using the isothermal recombinase polymerase amplification (RPA) method. With a unique probe system added to the reaction solution, the amplification product can be visualized on a simple lateral flow strip without further labelling. The combination of these methods was tested for sensitivity and specificity with various Plasmodium and other protozoa/bacterial strains, as well as with human DNA. Additional investigations were conducted to analyse the temperature optimum, reaction speed and robustness of this assay. Results The lateral flow RPA (LF-RPA) assay exhibited a high sensitivity and specificity. Experiments confirmed a detection limit as low as 100 fg of genomic P. falciparum DNA, corresponding to a sensitivity of approximately four parasites per reaction. All investigated P. falciparum strains (n = 77) were positively tested while all of the total 11 non-Plasmodium samples, showed a negative test result. The enzymatic reaction can be conducted under a broad range of conditions from 30-45°C with high inhibitory concentration of known PCR inhibitors. A time to result of 15 min from start of the reaction to read-out was determined. Conclusions Combining the isothermal RPA and the lateral flow detection is an approach to improve molecular diagnostic for P. falciparum in

  9. Loop-mediated isothermal amplification (LAMP)-based method for rapid mushroom species identification.

    Science.gov (United States)

    Vaagt, Franziska; Haase, Ilka; Fischer, Markus

    2013-02-27

    Toxic mushroom species, such as the death cap ( Amanita phalloides ), are responsible for most mushroom poisonings. In the present work, novel loop-mediated isothermal amplification (LAMP) assays were used for the differentiation of even closely related edible and toxic mushroom species. The applicability of these methods was tested by cross-reaction studies and analysis of spiked mushroom samples (raw and fried material). Contaminations at the level of 2% (w/w) could be detected in different mushroom blends. Three detection methods were used: agarose gel analysis, fluorimetric real-time detection, and visual detection by lateral flow dipsticks (LFD). The LAMP assay combined with LFD detection allows the identification of A. phalloides in about 2 h (including DNA extraction) at a very low level of technical equipment (micropestle, water bath, and mobile centrifuge), which makes this technique perfectly suited for on-site applications.

  10. Rapid thermal annealing of InAs/GaAs quantum dots under a GaAs proximity cap

    Energy Technology Data Exchange (ETDEWEB)

    Babinski, Adam; Jasinski, J.; Boz(overdot)ek, R.; Szepielow, A.; Baranowski, J. M.

    2001-10-15

    The effect of postgrowth rapid thermal annealing (RTA) on GaAs proximity-capped structures with self-assembled InAs/GaAs quantum dots (QDs) is investigated using transmission electron microscopy (TEM) and photoluminescence (PL). As can be seen from the TEM images, QDs increase their lateral sizes with increasing annealing temperature (up to 700 C). QDs cannot be distinguished after RTA at temperature 800 C or higher, and substantial thickening of the wetting layer can be seen instead. The main PL peak blueshifts as a result of RTA. We propose that in the as-grown sample as well, as in samples annealed at temperatures up to 700 C, the peak is due to the QDs. After RTA at 800 C and higher the PL peak is due to a modified wetting layer. Relatively fast dissolution of QDs is explained in terms of strain-induced lateral Ga/In interdiffusion. It is proposed that such a process may be of importance in proximity-capped RTA, when no group-III vacancy formation takes place at the sample/capping interface.

  11. Contacts realization by rapid thermal annealing in multicrystalline silicon solar cells with special emphasis on metal influence

    Energy Technology Data Exchange (ETDEWEB)

    El Omari, H.; Boyeaux, J.P.; Laugier, A. [Institut National des Sciences Appliquees de Lyon, Villeurbanne (France). Lab. de Physique de la Matiere

    1994-12-31

    To improve the quality of the screen printing contacts, the authors have previously shown the capability to sinter the screen printed contacts by Rapid Thermal Annealing (RTA) instead of commercial sintering; they have also noticed that the commonly used TiO{sub 2} coating deposited by spray enhances the quality of the contact either with classical annealing or RTA. The aim of the present work is to analyze the metal influence on either front or back contacts realization by RTA on Polix p type multicrystalline silicon subsequently phosphorus diffused. The screen printed contact was replaced by the chosen metal dot obtained by evaporation. The authors have studied: Al/TiO{sub 2}; Ag/Al/TiO{sub 2}; Cu/Al/TiO{sub 2}; Pt/Al/TiO{sub 2} and Cu/Cr/TiO{sub 2}. The RTA treatments were carried out at various temperatures and annealing time in an Ar ambience. The quality of the contacts are analyzed from I(V) characteristics, and possible diffusions of metallic species are characterized by SIMS experiments.

  12. Loop-mediated isothermal amplification: rapid detection of Angiostrongylus cantonensis infection in Pomacea canaliculata

    Directory of Open Access Journals (Sweden)

    Zhuo MingMing

    2011-10-01

    Full Text Available Abstract Background Angiostrongylus cantonensis is a zoonotic parasite that causes eosinophilic meningitis in humans. The most common source of infection with A. cantonensis is the consumption of raw or undercooked mollusks (e.g., snails and slugs harbouring infectious third-stage larvae (L3. However, the parasite is difficult to identify in snails. The purpose of this study was to develop a quick, simple molecular method to survey for A. cantonensis in intermediate host snails. Findings We used a loop-mediated isothermal amplification (LAMP assay, which was performed using Bst DNA polymerase. Reactions amplified the A. cantonensis 18S rRNA gene and demonstrated high sensitivity; as little as 1 fg of DNA was detected in the samples. Furthermore, no cross-reactivity was found with other parasites such as Toxoplasma gondii, Plasmodium falciparum, Schistosoma japonicum, Clonorchis sinensis, Paragonimus westermani and Anisakis. Pomacea canaliculata snails were exposed to A. cantonensis first-stage larvae (L1 in the laboratory, and L3 were observed in the snails thirty-five days after infection. All nine samples were positive as determined by the LAMP assay for A. cantonensis, which was identified as positive by using PCR and microscopy, this demonstrates that LAMP is sensitive and effective for diagnosis. Conclusions LAMP is an appropriate diagnostic method for the routine identification of A. cantonensis within its intermediate host snail P. canaliculata because of its simplicity, sensitivity, and specificity. It holds great promise as a useful monitoring tool for A. cantonensis in endemic regions.

  13. Development and evaluation of loop-mediated isothermal amplification assay for rapid detection of Capripoxvirus

    Directory of Open Access Journals (Sweden)

    Kanisht Batra

    2015-11-01

    Full Text Available Aim: The present study was undertaken to develop a nucleic acid-based diagnostic assay loop-mediated isothermal amplification assay (LAMP targeting highly conserved genomic regions of Capripoxvirus (CaPVs and its comparative evaluation with real-time polymerase chain reaction (PCR. Material and Methods: Lyophilized vaccine strain of sheeppox virus (SPPV was used for optimization of LAMP assay. The LAMP assay was designed using envelope immunogenic protein (P32 coding gene targeting highly conserved genomic regions of CaPV responsible for causing sheep pox, goat pox, and lumpy skin disease in sheep, goat and cattle respectively. Serial tenfold dilution of SPPV recombinant plasmid DNA was used for a calculating limit of detection. Analytical sensitivity and specificity were performed. Results: The test described is quick (30 min, sensitive and specific for detection of CaPVs. The described assay did not show any cross-reactivity to other related viruses that cause apparently similar clinical signs. It was found to be ten times more sensitive than conventional PCR however, 100 times less sensitive than quantitative PCR (qPCR. LAMP assay results were monitored by color change method using picogreen dye and agarose gel electrophoresis. Conclusion: LAMP assay can be a very good alternative for CaPV detection to other molecular techniques requiring sophisticated equipments.

  14. Development and evaluation of loop-mediated isothermal amplification assay for rapid detection of Capripoxvirus.

    Science.gov (United States)

    Batra, Kanisht; Kumar, Aman; Kumar, Vinay; Nanda, Trilok; Maan, Narender S; Maan, Sushila

    2015-11-01

    The present study was undertaken to develop a nucleic acid-based diagnostic assay loop-mediated isothermal amplification assay (LAMP) targeting highly conserved genomic regions of Capripoxvirus (CaPVs) and its comparative evaluation with real-time polymerase chain reaction (PCR). Lyophilized vaccine strain of sheeppox virus (SPPV) was used for optimization of LAMP assay. The LAMP assay was designed using envelope immunogenic protein (P32) coding gene targeting highly conserved genomic regions of CaPV responsible for causing sheep pox, goat pox, and lumpy skin disease in sheep, goat and cattle respectively. Serial tenfold dilution of SPPV recombinant plasmid DNA was used for a calculating limit of detection. Analytical sensitivity and specificity were performed. The test described is quick (30 min), sensitive and specific for detection of CaPVs. The described assay did not show any cross-reactivity to other related viruses that cause apparently similar clinical signs. It was found to be ten times more sensitive than conventional PCR however, 100 times less sensitive than quantitative PCR (qPCR). LAMP assay results were monitored by color change method using picogreen dye and agarose gel electrophoresis. LAMP assay can be a very good alternative for CaPV detection to other molecular techniques requiring sophisticated equipments.

  15. Numerical simulation of a plane turbulent mixing layer, with applications to isothermal, rapid reactions

    Science.gov (United States)

    Lin, P.; Pratt, D. T.

    1987-01-01

    A hybrid method has been developed for the numerical prediction of turbulent mixing in a spatially-developing, free shear layer. Most significantly, the computation incorporates the effects of large-scale structures, Schmidt number and Reynolds number on mixing, which have been overlooked in the past. In flow field prediction, large-eddy simulation was conducted by a modified 2-D vortex method with subgrid-scale modeling. The predicted mean velocities, shear layer growth rates, Reynolds stresses, and the RMS of longitudinal velocity fluctuations were found to be in good agreement with experiments, although the lateral velocity fluctuations were overpredicted. In scalar transport, the Monte Carlo method was extended to the simulation of the time-dependent pdf transport equation. For the first time, the mixing frequency in Curl's coalescence/dispersion model was estimated by using Broadwell and Breidenthal's theory of micromixing, which involves Schmidt number, Reynolds number and the local vorticity. Numerical tests were performed for a gaseous case and an aqueous case. Evidence that pure freestream fluids are entrained into the layer by large-scale motions was found in the predicted pdf. Mean concentration profiles were found to be insensitive to Schmidt number, while the unmixedness was higher for higher Schmidt number. Applications were made to mixing layers with isothermal, fast reactions. The predicted difference in product thickness of the two cases was in reasonable quantitative agreement with experimental measurements.

  16. Rapid construction of insulated genetic circuits via synthetic sequence-guided isothermal assembly.

    Science.gov (United States)

    Torella, Joseph P; Boehm, Christian R; Lienert, Florian; Chen, Jan-Hung; Way, Jeffrey C; Silver, Pamela A

    2014-01-01

    In vitro recombination methods have enabled one-step construction of large DNA sequences from multiple parts. Although synthetic biological circuits can in principle be assembled in the same fashion, they typically contain repeated sequence elements such as standard promoters and terminators that interfere with homologous recombination. Here we use a computational approach to design synthetic, biologically inactive unique nucleotide sequences (UNSes) that facilitate accurate ordered assembly. Importantly, our designed UNSes make it possible to assemble parts with repeated terminator and insulator sequences, and thereby create insulated functional genetic circuits in bacteria and mammalian cells. Using UNS-guided assembly to construct repeating promoter-gene-terminator parts, we systematically varied gene expression to optimize production of a deoxychromoviridans biosynthetic pathway in Escherichia coli. We then used this system to construct complex eukaryotic AND-logic gates for genomic integration into embryonic stem cells. Construction was performed by using a standardized series of UNS-bearing BioBrick-compatible vectors, which enable modular assembly and facilitate reuse of individual parts. UNS-guided isothermal assembly is broadly applicable to the construction and optimization of genetic circuits and particularly those requiring tight insulation, such as complex biosynthetic pathways, sensors, counters and logic gates.

  17. Rapid construction of insulated genetic circuits via synthetic sequence-guided isothermal assembly

    Energy Technology Data Exchange (ETDEWEB)

    Torella, JP; Boehm, CR; Lienert, F; Chen, JH; Way, JC; Silver, PA

    2013-12-28

    In vitro recombination methods have enabled one-step construction of large DNA sequences from multiple parts. Although synthetic biological circuits can in principle be assembled in the same fashion, they typically contain repeated sequence elements such as standard promoters and terminators that interfere with homologous recombination. Here we use a computational approach to design synthetic, biologically inactive unique nucleotide sequences (UNSes) that facilitate accurate ordered assembly. Importantly, our designed UNSes make it possible to assemble parts with repeated terminator and insulator sequences, and thereby create insulated functional genetic circuits in bacteria and mammalian cells. Using UNS-guided assembly to construct repeating promoter-gene-terminator parts, we systematically varied gene expression to optimize production of a deoxychromoviridans biosynthetic pathway in Escherichia coli. We then used this system to construct complex eukaryotic AND-logic gates for genomic integration into embryonic stem cells. Construction was performed by using a standardized series of UNS-bearing BioBrick-compatible vectors, which enable modular assembly and facilitate reuse of individual parts. UNS-guided isothermal assembly is broadly applicable to the construction and optimization of genetic circuits and particularly those requiring tight insulation, such as complex biosynthetic pathways, sensors, counters and logic gates.

  18. Rapid and sensitive detection of Bordetella bronchiseptica by loop-mediated isothermal amplification (LAMP

    Directory of Open Access Journals (Sweden)

    Hui Zhang

    2013-10-01

    Full Text Available Bordetella bronchiseptica causes acute and chronic respiratory infections in diverse animal species and occasionally in humans. In this study, we described the establishment of a simple, sensitive and cost-efficient loop-mediated isothermal amplification (LAMP assay for the detection of B. bronchiseptica. A set of primers towards a 235 bp region within the flagellum gene of B. bronchiseptica was designed with online software.. The specificity of the LAMP assay was examined by using 6 porcine pathogens and 100 nasal swabs collected from healthy pigs and suspect infected pigs. The results indicated that positive reactions were confirmed for all B. bronchiseptica and no cross-reactivity was observed from other non-B. bronchiseptica. In sensitivity evaluations, the technique successfully detected a serial dilutions of extracted B. bronchiseptica DNA with a detection limit of 9 copies, which was 10 times more sensitive than that of PCR. Compared with conventional PCR, the higher sensitivity of LAMP method and no need for the complex instrumentation make this LAMP assay a promising alternative for the diagnosis of B. bronchiseptica in rural areas and developing countries where there lacks of complex laboratory services.

  19. Development of a Loop-Mediated Isothermal Amplification Assay for Rapid Detection of Trichosporon asahii in Experimental and Clinical Samples

    Science.gov (United States)

    Zhou, Jianfeng; Liao, Yong; Li, Haitao; Lu, Xuelian; Han, Xiufeng; Tian, Yanli; Chen, Shanshan; Yang, Rongya

    2015-01-01

    Invasive trichosporonosis is a deep mycosis found mainly in immunocompromised hosts, and the major pathogen is Trichosporon asahii. We detected the species-specific intergenic spacers (IGS) of rRNA gene of T. asahii using a loop-mediated isothermal amplification (LAMP) assay in 15 isolates with 3 different visualization methods, including SYBR green detection, gel electrophoresis, and turbidimetric methods. The LAMP assay displayed superior rapidity to other traditional methods in the detection time; that is, only 1 h was needed for detection and identification of the pathogen DNA. Furthermore, the detection limit of the LAMP assay was more sensitive than the PCR assay. We also successfully detect the presence of T. asahii in samples from experimentally infected mice and samples from patients with invasive trichosporonosis caused by T. asahii, suggesting that this method may become useful in clinical applications in the near future. PMID:25692144

  20. Development of a Rapid and Sensitive Method for Detection of African Swine Fever Virus Using Loop-Mediated Isothermal Amplification

    Directory of Open Access Journals (Sweden)

    Xulong Wu

    Full Text Available ABSTRACT A loop-mediated isothermal amplification (LAMP assay was developed for rapid, sensitive and specific detection of African swine fever virus (ASFV. A set of LAMP primers was designed based on the sequence of the ASFV gene K205R. Reaction temperature and time were optimized to 64 oC and 60 min, respectively. LAMP products were detected by agarose gel electrophoresis or visually with the addition of fluorescent dye. The detection limit of the LAMP assay was approximately 6 copies of the target gene per microliter, 100 times more sensitive than conventional PCR. LAMP is a simple and inexpensive molecular assay format for ASFV detection. To date, African swine fever has not been reported in China. LAMP can be used to monitor ASFV spread into China, thereby reducing the threat of ASF.

  1. Rapid detection of newly isolated Tembusu-related Flavivirus by reverse-transcription loop-mediated isothermal amplification assay

    Directory of Open Access Journals (Sweden)

    Wang Youling

    2011-12-01

    Full Text Available Abstract Background From April 2010 to January 2011, a severe new viral disease had devastated most duck-farming regions in China. This disease affected not only laying ducks but also meat ducks, causing huge economic losses for the poultry industry. The objective of this study is to develop a one-step reverse transcription loop-mediated isothermal amplification (RT-LAMP assay for the detection of the new virus related to Tembusu-related Flavivirus. Results The RT-LAMP assay is very simple and rapid, and the amplification can be completed within 50 min under isothermal conditions at 63°C by a set of 6 primers targeting the E gene based on the sequences analysis of the newly isolated viruses and other closely related Flavivirus.The monitoring of gene amplification can also be visualized by using SYBR green I fluorescent dye. In addition, the RT-LAMP assay for newly isolated Tembusu-related Flavivirus showed higher sensitivity with an RNA detection-limit of 2 copies/μL compared with 190 copies/μL of the conventional RT-PCR method. The specificity was identified without cross reaction to other common avian pathogens. By screening a panel of clinical samples this method was more feasible in clinical settings and there was higher positive coincidence rate than conventional RT-PCR and virus isolation. Conclusion The RT-LAMP assay for newly isolated Tembusu-related Flavivirus is a valuable tool for the rapid and real-time detection not only in well-equipped laboratories but also in general conditions.

  2. Rapid crystallization of a-Si:H films with various silicon-to-hydrogen bonding configurations using rapid energy transfer annealing

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Y.-L. [Department of Electrical Engineering, National Chung Hsing University, Taichung 402, Taiwan (China)]. E-mail: yljiang@nchu.edu.tw; Chang, Y.-C. [Department of Electrical Engineering, National Chung Hsing University, Taichung 402, Taiwan (China)

    2006-04-03

    Hydrogenated amorphous silicon (a-Si:H) films were prepared by changing substrate temperature of plasma-enhanced chemical vapor deposition to induce different contents of monohydride and polyhydride bonds, which were then crystallized into polysilicon (poly-Si) films by rapid energy transfer annealing. Fourier transform infrared and transmission spectra show that the formation of numerous polyhydride bonds increases the hydrogen content and reduces the refractive index of a-Si:H films. The rise in the concentration of polyhydride bonds in as-deposited a-Si:H films can result in the increase of ultraviolet reflectance, small peak shift, and change in full width at half maximum of Raman scattering and X-ray diffraction peaks of the obtained poly-Si films after annealing. These results demonstrate that high-concentration polyhydride bonds can promote the rapid crystallization of a-Si:H and obtain high-crystallinity poly-Si films. Transmission electron microscopy identifies that the poly-Si films have the typical dendrite-like grain structure.

  3. Rapid sex identification of papaya (Carica papaya) using multiplex loop-mediated isothermal amplification (mLAMP).

    Science.gov (United States)

    Hsu, Te-Hua; Gwo, Jin-Chywan; Lin, Kuan-Hung

    2012-10-01

    Papaya (Carica papaya L.) is established as a cash crop throughout the tropical and subtropical regions due to its easy adaptation to diverse agricultural conditions, high yields, and prompt returns. The sex types of papaya plants are hermaphrodite, male, and female. Among them, hermaphroditic plants are the major type in papaya production, because the fruit has commercial advantages over that of the other sexes. Sex inheritance in papaya is determined by the M and M(h) dominant alleles in males and hermaphrodites, respectively, and a recessive m allele in females. Currently, all hermaphrodite seeds are not available due to the lethality of dominant homozygosity. Therefore, in this study, six male-hermaphrodite-specific markers were developed for a rapid sex identification using multiplex loop-mediated isothermal amplification (mLAMP) to efficiently and precisely select hermaphroditic individuals in the seedling or early growth stage. The LM1-LAMP assay consisted of two sex-LAMP reactions for amplifying two male-specific markers (T12 and Cpsm90) in one reaction, and showed several advantages in terms of a rapid reaction time (papaya production.

  4. Rapid sex identification method of spinach (Spinacia oleracea L.) in the vegetative stage using loop-mediated isothermal amplification.

    Science.gov (United States)

    Fujita, Naoko; Ayukawa, Yu; Fuke, Mitsutoshi; Teraoka, Tohru; Watanabe, Kyoko; Arie, Tsutomu; Komatsu, Ken

    2017-01-01

    A LAMP-mediated, simple and rapid method for sex identification in spinach was developed. Nutrient compositional analysis showed a higher iron content in male than female plants. Spinach (Spinacia oleracea L.) is a dioecious plant with its sex determined by the XY system. Male and female floral organs differ morphologically, but plants do not differ in the vegetative stage before flowering. PCR with Y chromosome markers has been used to determine the sex of dioecious plants before flowering. In this study, we developed a genotype-specific loop-mediated isothermal amplification (LAMP) for sex identification of individual vegetative-stage spinach plants, using primers designed for the genomic region flanked by male-specific markers. LAMP could specifically detect spinach males. The method was further modified to omit DNA purification and use just an aliquot of crude leaf extract homogenized in water. We compared the nutrient composition of males and females, finding higher amounts of iron in the males. Our method could therefore be used for rapidly discriminating male plants in the field, which is useful for efficient hybrid breeding.

  5. Loop-mediated isothermal amplification for the rapid detection of Chrysanthemum chlorotic mottle viroid (CChMVd).

    Science.gov (United States)

    Park, Jungan; Jung, Yuchul; Kil, Eui-Joon; Kim, Jaedeok; Thi Tran, Dung; Choi, Seung-Kook; Yoon, Ju-Yeon; Cho, Won Kyong; Lee, Sukchan

    2013-10-01

    Loop-mediated isothermal amplification (LAMP) is an established nucleic acid amplification method offering rapid, sensitive, and convenient diagnosis of infectious diseases. Chrysanthemum chlorotic mottle viroid (CChMVd) causes one of the most serious viral diseases in chrysanthemum in Korea. A sensitive LAMP assay was developed for rapidly detecting CChMVd infection. The assay was based on a set of four primers matching the specific region of the CChMVd genome. The CChMVd LAMP primer sets were designed using the sequences from nonsymptomatic and symptomatic CChMVd isolates in Korea. The efficiency and specificity of this method were optimized using Bst DNA polymerase, which allowed for increased viroid detection sensitivity. The reaction was carried out at 65 °C for 90 min, and was improved by adding SYBR Green I dye to the inside of the reaction tube lid prior to amplification. The results indicate that this LAMP method will be useful for chrysanthemum viroid disease monitoring and detecting CChMVd infectious disease. Crown Copyright © 2013. Published by Elsevier B.V. All rights reserved.

  6. Development of loop-mediated isothermal amplification (LAMP assay for rapid and sensitive identification of ostrich meat.

    Directory of Open Access Journals (Sweden)

    Amir Abdulmawjood

    Full Text Available Animal species identification is one of the primary duties of official food control. Since ostrich meat is difficult to be differentiated macroscopically from beef, therefore new analytical methods are needed. To enforce labeling regulations for the authentication of ostrich meat, it might be of importance to develop and evaluate a rapid and reliable assay. In the present study, a loop-mediated isothermal amplification (LAMP assay based on the cytochrome b gene of the mitochondrial DNA of the species Struthio camelus was developed. The LAMP assay was used in combination with a real-time fluorometer. The developed system allowed the detection of 0.01% ostrich meat products. In parallel, a direct swab method without nucleic acid extraction using the HYPLEX LPTV buffer was also evaluated. This rapid processing method allowed detection of ostrich meat without major incubation steps. In summary, the LAMP assay had excellent sensitivity and specificity for detecting ostrich meat and could provide a sampling-to-result identification-time of 15 to 20 minutes.

  7. Development of a Rapid Detection Method for Potato virus X by Reverse Transcription Loop-Mediated Isothermal Amplification

    Directory of Open Access Journals (Sweden)

    Joojin Jeong

    2015-09-01

    Full Text Available The primary step for efficient control of viral diseases is the development of simple, rapid, and sensitive virus detection. Reverse transcription loop-mediated isothermal amplification (RT-LAMP has been used to detect viral RNA molecules because of its simplicity and high sensitivity for a number of viruses. RT-LAMP for the detection of Potato virus X (PVX was developed and compared with conventional reverse transcription polymerase chain reaction (RT-PCR to demonstrate its advantages over RT-PCR. RT-LAMP reactions were conducted with or without a set of loop primers since one out of six primers showed PVX specificity. Based on real-time monitoring, RT-LAMP detected PVX around 30 min, compared to 120 min for RT-PCR. By adding a fluorescent reagent during the reaction, the extra step of visualization by gel electrophoresis was not necessary. RT-LAMP was conducted using simple inexpensive instruments and a regular incubator to evaluate whether RNA could be amplified at a constant temperature instead of using an expensive thermal cycler. This study shows the potential of RT-LAMP for the diagnosis of viral diseases and PVX epidemiology because of its simplicity and rapidness compared to RT-PCR.

  8. Rapid and sensitive detection of Plesiomonas shigelloides by loop-mediated isothermal amplification of the hugA gene.

    Directory of Open Access Journals (Sweden)

    Shuang Meng

    Full Text Available Plesiomonas shigelloides is one of the causative agents of human gastroenteritis, with increasing number of reports describing such infections in recent years. In this study, the hugA gene was chosen as the target to design loop-mediated isothermal amplification (LAMP assays for the rapid, specific, and sensitive detection of P. shigelloides. The performance of the assay with reference plasmids and spiked human stools as samples was evaluated and compared with those of quantitative PCR (qPCR. No false-positive results were observed for the 32 non-P. shigelloides strains used to evaluate assay specificity. The limit of detection for P. shigelloides was approximately 20 copies per reaction in reference plasmids and 5×10(3 CFU per gram in spiked human stool, which were more sensitive than the results of qPCR. When applied in human stool samples spiked with 2 low levels of P. shigelloides, the LAMP assays achieved accurate detection after 6-h enrichment. In conclusion, the LAMP assay developed in this study is a valuable method for rapid, cost-effective, and simple detection of P. shigelloides in basic clinical and field laboratories in the rural areas of China.

  9. A Simple and Rapid Identification Method for Mycobacterium bovis BCG with Loop-Mediated Isothermal Amplification.

    Directory of Open Access Journals (Sweden)

    Yuji Kouzaki

    Full Text Available Bacillus Calmette-Guérin (BCG is widely used as a live attenuated vaccine against Mycobacterium tuberculosis and is an agent for standard prophylaxis against the recurrence of bladder cancer. Unfortunately, it can cause severe infectious diseases, especially in immunocompromised patients, and the ability to immediately distinguish BCG from other M. tuberculosis complexes is therefore important. In this study, we developed a simple and easy-to-perform identification procedure using loop-mediated amplification (LAMP to detect deletions within the region of difference, which is deleted specifically in all M. bovis BCG strains. Reactions were performed at 64 °C for 30 min and successful targeted gene amplifications were detected by real-time turbidity using a turbidimeter and visual inspection of color change. The assay had an equivalent detection limit of 1.0 pg of genomic DNA using a turbidimeter whereas it was 10 pg with visual inspection, and it showed specificity against 49 strains of 44 pathogens, including M. tuberculosis complex. The expected LAMP products were confirmed through identical melting curves in real-time LAMP procedures. We employed the Procedure for Ultra Rapid Extraction (PURE kit to isolate mycobacterial DNA and found that the highest sensitivity limit with a minimum total cell count of mycobacterium (including DNA purification with PURE was up to 1 × 10(3 cells/reaction, based on color changes under natural light with FDA reagents. The detection limit of this procedure when applied to artificial serum, urine, cerebrospinal fluid, and bronchoalveolar lavage fluid samples was also about 1 × 10(3 cells/reaction. Therefore, this substitute method using conventional culture or clinical specimens followed by LAMP combined with PURE could be a powerful tool to enable the rapid identification of M. bovis BCG as point-of-care testing. It is suitable for practical use not only in resource-limited situations, but also in any

  10. Boosting photoelectrochemical performance of hematite photoanode with TiO2 underlayer by extremely rapid high temperature annealing

    Science.gov (United States)

    Wang, Dan; Chen, Ying; Zhang, Yang; Zhang, Xintong; Suzuki, Norihiro; Terashima, Chiaki

    2017-11-01

    Extremely rapid high temperature annealing (ER-HTA) was used to boost the photoelectrochemical (PEC) performance of hematite thin film deposited on a TiO2 nanosheet-modified SnO2:F substrate (FTO-TN-HM). The PEC performance of FTO-TN-HM photoanodes were strongly enhanced with increasing ER-HTA temperatures from 700 to 820 °C with a holding time as short as 30 s. The photocurrent density of FTO-TN-HM photoanode treated by ER-HTA at 800 °C was 0.49 mA cm-2 and interfacial hole transfer efficiency of 32% was achieved at 1.23 V vs. RHE, which were 18.8 and 16 times as great as FTO-TN-HM photoanodes annealed at 500 °C for 30 min, respectively. The effect of ER-HTA on the PEC performance of FTO-TN-HM photoanodes were studied comparatively, which suggested that the improved crystallinity, decreased recombination through surface states, and enhanced interfacial Ti4+ diffusion all contributed to their advanced PEC performance. Our studies confirm that the ER-HTA treatment is an effective method to improve the PEC properties of hematite photoanodes with TiO2 underlayer and might be applicable for other semiconducting photoelectrodes to get better PEC performance.

  11. The striking influence of rapid thermal annealing on InGaAsP grown by MBE: material and photovoltaic device

    Science.gov (United States)

    Ji, Lian; Tan, Ming; Ding, Chao; Honda, Kazuki; Harasawa, Ryo; Yasue, Yuya; Wu, Yuanyuan; Dai, Pan; Tackeuchi, Atsushi; Bian, Lifeng; Lu, Shulong; Yang, Hui

    2017-01-01

    Rapid thermal annealing (RTA) has been performed on InGaAsP solar cells with the bandgap energy of 1 eV grown by molecular beam epitaxy. With the employment of RTA under an optimized condition, the open voltage was increased from 0.45 to 0.5 V and the photoelectric conversion efficiency was increased from 11.87-13.2%, respectively, which was attributed to the crystal quality improvement of p-type InGaAsP and therefore a reduced recombination current inside depletion region. The integral photoluminescence (PL) intensity of p-type InGaAsP increased to 166 times after annealing at 800 °C and its PL decay time increased by one order of magnitude. While the changes of nominally undoped and n-doped InGaAsP were negligible. The different behaviors of the effect of RTA on InGaAsP of different doping types were attributed to the highly mobile "activator" - beryllium (Be) atom in p-type InGaAsP.

  12. Enhanced Photoelectrochemical Behavior of H-TiO2 Nanorods Hydrogenated by Controlled and Local Rapid Thermal Annealing.

    Science.gov (United States)

    Wang, Xiaodan; Estradé, Sonia; Lin, Yuanjing; Yu, Feng; Lopez-Conesa, Lluis; Zhou, Hao; Gurram, Sanjeev Kumar; Peiró, Francesca; Fan, Zhiyong; Shen, Hao; Schaefer, Lothar; Braeuer, Guenter; Waag, Andreas

    2017-12-01

    Recently, colored H-doped TiO2 (H-TiO2) has demonstrated enhanced photoelectrochemical (PEC) performance due to its unique crystalline core-disordered shell nanostructures and consequent enhanced conduction behaviors between the core-shell homo-interfaces. Although various hydrogenation approaches to obtain H-TiO2 have been developed, such as high temperature hydrogen furnace tube annealing, high pressure hydrogen annealing, hydrogen-plasma assisted reaction, aluminum reduction and electrochemical reduction etc., there is still a lack of a hydrogenation approach in a controlled manner where all processing parameters (temperature, time and hydrogen flux) were precisely controlled in order to improve the PEC performance of H-TiO2 and understand the physical insight of enhanced PEC performance. Here, we report for the first time a controlled and local rapid thermal annealing (RTA) approach to prepare hydrogenated core-shell H-TiO2 nanorods grown on F:SnO2 (FTO) substrate in order to address the degradation issue of FTO in the typical TiO2 nanorods/FTO system observed in the conventional non-RTA treated approaches. Without the FTO degradation in the RTA approach, we systematically studied the intrinsic relationship between the annealing temperature, structural, optical, and photoelectrochemical properties in order to understand the role of the disordered shell on the improved photoelectrochemical behavior of H-TiO2 nanorods. Our investigation shows that the improvement of PEC performance could be attributed to (i) band gap narrowing from 3.0 to 2.9 eV; (ii) improved optical absorption in the visible range induced by the three-dimensional (3D) morphology and rough surface of the disordered shell; (iii) increased proper donor density; (iv) enhanced electron-hole separation and injection efficiency due to the formation of disordered shell after hydrogenation. The RTA approach developed here can be used as a suitable hydrogenation process for TiO2 nanorods/FTO system for

  13. A lab-on-a-chip system with integrated sample preparation and loop-mediated isothermal amplification for rapid and quantitative detection of Salmonella spp. in food samples

    DEFF Research Database (Denmark)

    Sun, Yi; Than Linh, Quyen; Hung, Tran Quang

    2015-01-01

    and usually take a few hours to days to complete. In response to the demand for rapid on line or at site detection of pathogens, in this study, we describe for the first time an eight-chamber lab-on-a-chip (LOC) system with integrated magnetic beads-based sample preparation and loop-mediated isothermal...

  14. Development of an isothermal amplification-based assay for the rapid visual detection of Salmonella bacteria.

    Science.gov (United States)

    Liu, Hai-Bin; Zang, Yu-Xuan; Du, Xin-Jun; Li, Ping; Wang, Shuo

    2017-09-01

    The efficient and timely detection of pathogens is a major concern worldwide. The aim of this study was to establish a rapid detection method for Salmonella bacteria in food samples to facilitate timely treatment. Widely used detection methods currently include culture-based methods and PCR-based methods. The former are time consuming, requiring 2 to 3 d, whereas the latter have higher accuracy but are typically complicated, requiring expertise and expensive instruments. In this study, a sensitive and rapid approach for the visual and point-of-use detection of Salmonella bacteria based on recombinase polymerase amplification (RPA) and a lateral-flow (LF) nucleic acid strip was established. We designed a pair of primers according to the invA gene of Salmonella bacteria: one was modified with digoxin, and the other was modified with biotin. In the presence of the biotin- and digoxin-modified primers and target DNA, the RPA produced a substantial amount of duplex DNA attached to biotin and digoxin. The products were detected using LF strips through immunoreaction: anti-digoxin antibodies on the gold nanoparticles, digoxin on the duplex, streptavidin on the LF test line, and biotin on the duplex. The developed RPA-LF assay allowed detection of Salmonella genomic DNA in less than 20 min with simple water bath equipment or portable thermal equipment. In addition, the RPA-LF assay was highly sensitive, with a detection limit as low as 20 fg of target DNA or 1.05 × 101 cfu of bacteria in pure culture, and highly specific, exhibiting no cross-reaction with Staphylococcus aureus, Escherichia coli, Listeria monocytogenes, Shigella, Enterobacter aerogenes, or Campylobacter jejuni. Importantly, Salmonella could be detected in milk and chicken breast at concentrations as low as 1.05 × 100 cfu/mL or 1.05 × 100 cfu/g after enrichment for 2 h and in eggs at 1.05 × 100 cfu/g after enrichment for 4 h. Furthermore, RPA was more sensitive than PCR, which requires a thermal cycling

  15. Development of Isothermal Recombinase Polymerase Amplification Assay for Rapid Detection of Porcine Circovirus Type 2

    Directory of Open Access Journals (Sweden)

    Yang Yang

    2017-01-01

    Full Text Available Porcine circovirus virus type II (PCV2 is the etiology of postweaning multisystemic wasting syndrome (PMWS, porcine dermatitis, nephropathy syndrome (PDNS, and necrotizing pneumonia. Rapid diagnosis tool for detection of PCV2 plays an important role in the disease control and eradication program. Recombinase polymerase amplification (RPA assays using a real-time fluorescent detection (PCV2 real-time RPA assay and RPA combined with lateral flow dipstick (PCV2 RPA LFD assay were developed targeting the PCV2 ORF2 gene. The results showed that the sensitivity of the PCV2 real-time RPA assay was 102 copies per reaction within 20 min at 37°C and the PCV2 RPA LFD assay had a detection limit of 102 copies per reaction in less than 20 min at 37°C. Both assays were highly specific for PCV2, with no cross-reactions with porcine circovirus virus type 1, foot-and-mouth disease virus, pseudorabies virus, porcine parvovirus, porcine reproductive and respiratory syndrome virus, and classical swine fever virus. Therefore, the RPA assays provide a novel alternative for simple, sensitive, and specific identification of PCV2.

  16. Development of a loop-mediated Isothermal amplification assay for sensitive and rapid detection of Vibrio parahaemolyticus

    Directory of Open Access Journals (Sweden)

    Kawahara Ryuji

    2008-09-01

    Full Text Available Abstract Background Vibrio parahaemolyticus is a marine seafood-borne pathogen causing gastrointestinal disorders in humans. Thermostable direct hemolysin (TDH and TDH-related hemolysin (TRH are known as major virulence determinants of V. parahaemolyticus. Most V. parahaemolyticus isolates from the environment do not produce TDH or TRH. Total V. parahaemolyticus has been used as an indicator for control of seafood contamination toward prevention of infection. Detection of total V. parahaemolyticus using conventional culture- and biochemical-based assays is time-consuming and laborious, requiring more than three days. Thus, we developed a novel and highly specific loop-mediated isothermal amplification (LAMP assay for the sensitive and rapid detection of Vibrio parahaemolyticus. Results The assay provided markedly more sensitive and rapid detection of V. parahaemolyticus strains than conventional biochemical and PCR assays. The assay correctly identified 143 V. parahaemolyticus strains, but did not detect 33 non-parahaemolyticus Vibrio and 56 non-Vibrio strains. Sensitivity of the LAMP assay for direct detection of V. parahaemolyticus in pure cultures and in spiked shrimp samples was 5.3 × 102 CFU per ml/g (2.0 CFU per reaction. The sensitivity of the LAMP assay was 10-fold more sensitive than that of the conventional PCR assay. The LAMP assay was markedly faster, requiring for amplification 13–22 min in a single colony on TCBS agar from each of 143 V. parahaemolyticus strains and less than 35 min in spiked shrimp samples. The LAMP assay for detection of V. parahaemolyticus required less than 40 min in a single colony on thiosulfate citrate bile salt sucrose (TCBS agar and 60 min in spiked shrimp samples from the beginning of DNA extraction to final determination. Conclusion The LAMP assay is a sensitive, rapid and simple tool for the detection of V. parahaemolyticus and will facilitate the surveillance for control of contamination of V

  17. Investigation of Near-Surface Defects Induced by Spike Rapid Thermal Annealing in c-SILICON Solar Cells

    Science.gov (United States)

    Liu, Guodong; Ren, Pan; Zhang, Dayong; Wang, Weiping; Li, Jianfeng

    2016-01-01

    The defects induced by a spike rapid thermal annealing (RTA) process in crystalline silicon (c-Si) solar cells were investigated by the photoluminescence (PL) technique and the transmission electron microscopy (TEM), respectively. Dislocation defects were found to form in the near-surface junction region of the monocrystalline Si solar cell after a spike RTA process was performed at 1100∘C. Photo J-V characteristics were measured on the Si solar cell before and after the spike RTA treatments to reveal the effects of defects on the Si cell performances. In addition, the Silvaco device simulation program was used to study the effects of defects density on the cell performances by fitting the experimental data of RTA-treated cells. The results demonstrate that there was an obvious degradation in the Si solar cell performances when the defect density after the spike RTA treatment was above 1×1013cm-3.

  18. Characterization of phase development in non-isothermally annealed mould-cast and heat-treated Al-Mn-Sc-Zr alloys

    Energy Technology Data Exchange (ETDEWEB)

    Vlach, M., E-mail: martin.vlach@mff.cuni.cz; Stulikova, I.; Smola, B.; Zaludova, N.

    2010-12-15

    The effect of Mn addition on microstructure and mechanical properties during isochronal annealing in the temperature range of 20 deg. C - 570 deg. C of the mould-cast and heat-treated Al-Sc-Zr alloys with a various content of Mn and Zr was studied. The electrical resistometry together with the microhardness (HV0.3) measurements were compared to microstructure development. The microstructure development was examined by scanning electron microscopy, transmission electron microscopy and electron diffraction. Relative resistivity changes and the microhardness of the mould-cast and heat-treated Al-Mn-Sc-Zr alloys exhibit similar dependence on annealing temperature. Precipitation of the Al{sub 3}Sc particles is responsible for the peak microhardness in all these alloys. The microhardness decrease is slightly delayed during the isochronal annealing and during the high temperature heat treatment in the mould-cast alloy with the higher Zr-content due to a higher oversaturation of Zr. The decomposition sequence of the oversaturated solid solution of the studied Al-Mn-Sc-Zr alloys is compatible with the recently published decomposition sequence of the Al-Sc-Zr system and also with the formation of Mn,Fe-containing particles. It seems very probable that the addition of Mn does not influence the decomposition of solid solution of the ternary Al-Sc-Zr system. - Research Highlights: {yields} Al{sub 3}Sc particles are responsible for the peak microhardness in all the studied alloys. {yields} The microhardness decrease is delayed in the alloy with the higher Zr-content. {yields} The peak hardening of the heat-treated alloys is shifted to higher temperatures. {yields} Mn does not influence the decomposition sequence of the Al-Sc-Zr system.

  19. Development and evaluation of a novel and rapid detection assay for Botrytis cinerea based on loop-mediated isothermal amplification.

    Directory of Open Access Journals (Sweden)

    Ya-Bing Duan

    Full Text Available Botrytis cinerea is a devastating plant pathogen that causes grey mould disease. In this study, we developed a visual detection method of B. cinerea based on the Bcos5 sequence using loop-mediated isothermal amplification (LAMP with hydroxynaphthol blue dye (HNB. The LAMP reaction was optimal at 63 °C for 45 min. When HNB was added prior to amplification, samples with B. cinerea DNA developed a characteristic sky blue color after the reaction but those without DNA or with DNA of other plant pathogenic fungi did not. Results of HNB staining method were reconfirmed when LAMP products were subjected to gel electrophoresis. The detection limit of this LAMP assay for B. cinerea was 10(-3 ng µL(-1 of genomic DNA per reaction, which was 10-fold more sensitive than conventional PCR (10(-2 ng µL(-1. Detection of the LAMP assay for inoculum of B. cinerea was possible in the inoculated tomato and strawberry petals. In the 191 diseased samples, 180 (94.2% were confirmed as positive by LAMP, 172 (90.1% positive by the tissue separation, while 147 (77.0% positive by PCR. Because the LAMP assay performed well in aspects of sensitivity, specificity, repeatability, reliability, and visibility, it is suitable for rapid detection of B. cinerea in infected plant materials prior to storage and during transportation, such as cut flowers, fruits and vegetables.

  20. Development and evaluation of a novel and rapid detection assay for Botrytis cinerea based on loop-mediated isothermal amplification.

    Science.gov (United States)

    Duan, Ya-Bing; Ge, Chang-Yan; Zhang, Xiao-Ke; Wang, Jian-Xin; Zhou, Ming-Guo

    2014-01-01

    Botrytis cinerea is a devastating plant pathogen that causes grey mould disease. In this study, we developed a visual detection method of B. cinerea based on the Bcos5 sequence using loop-mediated isothermal amplification (LAMP) with hydroxynaphthol blue dye (HNB). The LAMP reaction was optimal at 63 °C for 45 min. When HNB was added prior to amplification, samples with B. cinerea DNA developed a characteristic sky blue color after the reaction but those without DNA or with DNA of other plant pathogenic fungi did not. Results of HNB staining method were reconfirmed when LAMP products were subjected to gel electrophoresis. The detection limit of this LAMP assay for B. cinerea was 10(-3) ng µL(-1) of genomic DNA per reaction, which was 10-fold more sensitive than conventional PCR (10(-2) ng µL(-1)). Detection of the LAMP assay for inoculum of B. cinerea was possible in the inoculated tomato and strawberry petals. In the 191 diseased samples, 180 (94.2%) were confirmed as positive by LAMP, 172 (90.1%) positive by the tissue separation, while 147 (77.0%) positive by PCR. Because the LAMP assay performed well in aspects of sensitivity, specificity, repeatability, reliability, and visibility, it is suitable for rapid detection of B. cinerea in infected plant materials prior to storage and during transportation, such as cut flowers, fruits and vegetables.

  1. Rapid genotyping of carcinogenic human papillomavirus by loop-mediated isothermal amplification using a new automated DNA test (Clinichip HPV™).

    Science.gov (United States)

    Satoh, Toyomi; Matsumoto, Koji; Fujii, Takuma; Sato, Osamu; Gemma, Nobuhiro; Onuki, Mamiko; Saito, Hiroshi; Aoki, Daisuke; Hirai, Yasuo; Yoshikawa, Hiroyuki

    2013-03-01

    This study was designed to evaluate the Clinichip HPV test, a new DNA test that detects carcinogenic human papillomavirus (HPV) rapidly by loop-mediated isothermal amplification and performs genotyping of all 13 carcinogenic types using automated DNA chip technology with an assay time 2.5h. Using this test, 247 Japanese women (109 with normal cytology, 43 with cervical intraepithelial neoplasia grade 1, 60 with cervical intraepithelial neoplasia grade 2/3 and 35 with invasive cervical cancer) were tested for carcinogenic HPV genotypes. The results were compared to those obtained by the polymerase chain reaction-amplified DNA sequencing using 13 type-specific primers. Overall, there was very good agreement for the detection of carcinogenic HPV between the Clinichip test and direct sequencing, with 95.5% total agreement and a kappa value of 0.91. Comparison of the detection of individual HPV types shows that the overall agreement was also high (range: 96.8-100%). In women with cervical intraepithelial neoplasia grade 2 or worse, the detection rate of carcinogenic HPV was 95.7% by both the Clinichip test and the direct-sequencing method, indicating complete agreement between the two methods. In conclusion, it was found that the Clinichip test is a promising new laboratory method for genotyping of carcinogenic HPV. Copyright © 2012 Elsevier B.V. All rights reserved.

  2. A rapid, simple and sensitive loop-mediated isothermal amplification method to detect Anaplasma bovis in sheep and goats samples.

    Science.gov (United States)

    Wang, Jinhong; Zhang, Yan; Cui, Yanyan; Yan, Yaqun; Wang, Xiaoxing; Wang, Rongjun; Jian, Fuchun; Zhang, Longxian; Ning, Changshen

    2017-03-27

    A loop-mediated isothermal amplification (LAMP) technique has been widely used in detecting the nucleic acid of various pathogenic bacteria. In this study, a set of four LAMP primers was designed to specifically test Anaplasma bovis. The LAMP assay was performed at 62°C for 60min in a water bath. The specificity was confirmed by amplifying A. bovis isolate, while no cross reaction was observed with other five pathogens (Anaplasma bovis, Anaplasma phagocytophilum, Theileria luwenshuni, Babesia motasi and Schistosoma japonicum). The sensitivity of LAMP was 5×10(0)copies/μL, 100 times more than that of conventional PCR (5×10(2)copies/μL). Of 120 blood DNA extracted from sheep and goats field samples, 81 (67.5%), 22 (18.3%) and 43 (35.8%) were positively detected by LAMP, conventional PCR and nested PCR, respectively. The findings indicated that the developed LAMP assay is a new convenient tool for rapid and cost-effective detection of A. bovis. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. A simple and rapid method for detection of Goose Parvovirus in the field by loop-mediated isothermal amplification

    Directory of Open Access Journals (Sweden)

    MingShu Wang

    2010-01-01

    Full Text Available Abstract Background Goose parvovirus (GPV is a Dependovirus associated with latent infection and mortality in geese. Currently, in a worldwide scale, GPV severely affects geese production. The objective of this study is to develop a loop-mediated isothermal amplification (LAMP method for the sensitive, rapid, and inexpensive detection of GPV in the field. Results A set of six specific primers was designed by targeting the GPV VP3 DNA. With Bst DNA polymerase large fragment, the target DNA could be amplified at 65°C as early as 20 min of incubation in a simple water bath. A positive reaction was identified through the detection of the LAMP product by color change visible to the naked eye. The detection limit of the assay was 28 copies/μl of plasmid pVP3, and with equal sensitivity and specificity to fluorescent quantitative real-time PCR (FQ-PCR. Conclusions The high sensitivity, specificity, and simplicity, as well as the high throughput, make this method suitable for specific detection of GPV infection in both field conditions and laboratory settings. The utilization of complicated equipment and conduct of technical training on the GPV LAMP were not necessary.

  4. Loop-mediated isothermal amplification (LAMP) as an alternative to PCR: A rapid on-site detection of gene doping.

    Science.gov (United States)

    Salamin, Olivier; Kuuranne, Tiia; Saugy, Martial; Leuenberger, Nicolas

    2017-10-17

    Innovation in medical research has been diverted at multiple occasions to enhance human performance. The predicted great progress in gene therapy has raised some concerns regarding its misuse in the world of sports (gene doping) for several years now. Even though there is no evidence that gene doping has ever been used in sports, the continuous improvement of gene therapy techniques increases the likelihood of abuse. Therefore, since 2004, efforts have been invested by the anti-doping community and WADA for the development of detection methods. Several nested PCR and qPCR-based strategies exploiting the absence of introns in the transgenic DNA have been proposed for the long-term detection of transgene in blood. Despite their great sensitivity, those protocols are hampered by limitations of the techniques that can be cumbersome and costly. The purpose of this perspective is to describe a new approach based on loop-mediated isothermal amplification (LAMP) for the detection of gene doping. This protocol enables a rapid and simple method to amplify nucleic acids with a high sensitivity and specificity and with a simple visual detection of the results. LAMP is already being used in clinical application for the detection of viruses or mutations. Therefore, this technique has the potential to be further developed for the detection of foreign genetic material in elite athletes. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  5. Isothermal and rapid detection of pathogenic microorganisms using a nano-rolling circle amplification-surface plasmon resonance biosensor.

    Science.gov (United States)

    Shi, Dachuan; Huang, Junfu; Chuai, Zhengran; Chen, Dong; Zhu, Xiaoyan; Wang, Huan; Peng, Jia; Wu, Haiyan; Huang, Qing; Fu, Weiling

    2014-12-15

    Rolling circle amplification (RCA) of DNA is a sensitive and cost effective method for the rapid identification of pathogens without the need for sequencing. In this study, a surface plasmon resonance DNA biosensor based on RCA with a gold (Au) nanoparticle surface was established for isothermal identification of DNA. The probes included a specific padlock probe, a capture probe (CP), which is bound to biotin, and an Au nanoparticle-modified probe, which hybridizes with the RCA products. The CP was assembled on gold nanoparticles to increase its ability to bind and hybridize. The linear padlock probe, which was designed to circularize by ligation upon recognition of the bacterial pathogen-specific sequence in 16S rDNA, hybridizes to fully complementary sequences within the CP. Upon recognition, each target gene DNA is distinguished by localization onto the corresponding channel on the chip surface. Then, the immobilized CPs act as primers to begin the in situ solid-phase RCA reaction, which produces long single-stranded DNA. The RCA products fixed on the chip surface cause significant surface plasmon resonance angle changes. We demonstrated that six different bacterial pathogens can be identified simultaneously and that 0.5 pM of synthetic oligonucleotides and 0.5 pg μl(-1) of genomic DNA from clinical samples can be detected by this method with low background signals. Therefore, the multiplex diagnostic method provides a highly sensitive and specific approach for the rapid identification of positive samples. Copyright © 2014 Elsevier B.V. All rights reserved.

  6. Loop-mediated isothermal amplification (LAMP) test for specific and rapid detection of Brucella abortus in cattle.

    Science.gov (United States)

    Karthik, K; Rathore, Rajesh; Thomas, Prasad; Arun, T R; Viswas, K N; Agarwal, R K; Manjunathachar, H V; Dhama, Kuldeep

    2014-01-01

    Brucella abortus, the major causative agent of abortion in cattle and a zoonotic pathogen, needs to be diagnosed at an early stage. Loop-mediated isothermal amplification (LAMP) test is easy to perform and also promising to be adapted at field level. To develop a LAMP assay for specific and rapid detection of B. abortus from clinical samples of cattle. LAMP primers were designed targeting BruAb2_0168 region using specific software tool and LAMP was optimized. The developed LAMP was tested for its specificity with 3 Brucella spp. and 11 other non-Brucella spp. Sensitivity of the developed LAMP was also carried out with known quantity of DNA. Cattle whole blood samples and aborted fetal stomach contents were collected and used for testing with developed LAMP assay and results were compared with polymerase chain reaction (PCR). The developed LAMP assay works at 61 °C for 60 min and the detection limit was observed to be 100-fold more than the conventional PCR that is commonly used for diagnosis of B. abortus. Clinical sensitivity and specificity of the developed LAMP assay was 100% when compared with Rose Bengal plate test and standard tube agglutination test. SYB® green dye I was used to visualize the result with naked eye. The novelty of the developed LAMP assay for specifically detecting B. abortus infection in cattle along with its inherent rapidness and high sensitivity can be employed for detecting this economically important pathogen of cattle at field level as well be exploited for screening of human infections.

  7. Rapid Diagnosis of Trichomonas vaginalis by Testing Vaginal Swabs in an Isothermal Helicase-Dependent AmpliVue Assay.

    Science.gov (United States)

    Gaydos, Charlotte A; Hobbs, Marcia; Marrazzo, Jeanne; Schwebke, Jane; Coleman, Jenell S; Masek, Billie; Dize, Laura; Jang, Dan; Li, Jenny; Chernesky, Max

    2016-06-01

    The AmpliVue Trichomonas Assay (Quidel) is a new Federal Drug Administration-cleared rapid test for qualitative detection of Trichomonas vaginalis (TV) DNA in female vaginal specimens. The assay is based on BioHelix's helicase-dependent amplification isothermal technology in conjunction with a disposable lateral-flow detection device, with a total turnaround time of approximately 45 minutes. The objective of this study was to compare the performance of this new assay to wet preparation and culture as well as to another Federal Drug Administration-cleared nucleic acid amplification assay. Four clinician collected vaginal swabs were obtained from women attending sexually transmitted disease, family planning, and OB/GYN clinics and tested by AmpliVue Trichomonas Assay and comparator tests: saline microscopy, TV culture (InPouch), and Aptima TV. AmpliVue Trichomonas Assay results were compared with a composite positive comparator (CPC) as determined by the results from culture and/or wet mount microscopic examination. At least one of either the wet preparation or culture reference test results was required to be positive to establish CPC. A total of 992 patients, 342 symptomatic and 650 asymptomatic patients, were included in the study. Results for AmpliVue for all women combined compared with saline microscopy and culture as a CPC yielded a sensitivity of 100%. Specificity for all women was 98.2%. Overall percent agreement versus Aptima TV was 97.8%. Sensitivity for AmpliVue compared with Aptima was 90.7% %, whereas specificity was 98.9%. The rapid AmpliVue Trichomonas Assay performed as well as microscopy and culture, and had comparable sensitivity and specificity to another nucleic acid amplification test for the detection of TV. This study provided evidence of new diagnostic options and indicated very good performance of amplified testing for detection of TV in symptomatic and asymptomatic women.

  8. Rapid Diagnosis of Trichomonas vaginalis by Testing Vaginal Swabs in an Isothermal Helicase-Dependent AmpliVue™ Assay

    Science.gov (United States)

    Gaydos, Charlotte A.; Hobbs, Marcia; Marrazzo, Jeanne; Schwebke, Jane; Coleman, Jenell S.; Masek, Billie; Dize, Laura; Jang, Dan; Li, Jenny; Chernesky, Max

    2016-01-01

    Background The AmpliVue™ Trichomonas Assay (Quidel) is a new FDA cleared rapid test for qualitative detection of Trichomonas vaginalis (TV) DNA in female vaginal specimens. The assay is based on BioHelix’s Helicase-Dependent Amplification (HDA) isothermal technology in conjunction with a disposable lateral-flow detection device, with a total turn-around time of approximately 45 minutes. Objective The objective of this study was to compare the performance of this new assay to wet preparation and culture, as well as to another FDA cleared nucleic acid amplification assay. Methods Four clinician collected vaginal swabs were obtained from women attending STD, family planning, and OB/GYN clinics and tested by AmpliVue™ Trichomonas Assay and comparator tests: saline microscopy, TV culture (InPouch™), and Aptima® TV (ATV). AmpliVue™ Trichomonas Assay results were compared to a composite positive comparator (CPC) as determined by the results from culture and/or wet mount microscopic examination. At least one of either the wet preparation or culture reference test results was required to be positive to establish CPC. Results A total of 992 patients, 342 symptomatic and 650 asymptomatic patients, were included in the study. Results for AmpliVue for all women combined compared to saline microscopy and culture as a composite positive comparator yielded a sensitivity of 100%. Specificity for all women was 98.2%. Overall percent agreement versus Aptima® TV was 97.8%. Sensitivity for AmpliVue compared to Aptima® was 90.7% %, while specificity was 98.9%. Conclusions The rapid AmpliVue™ Trichomonas Assay performed as well as microscopy and culture, and had comparable sensitivity and specificity to another NAAT for the detection of TV. This study provided evidence of new diagnostic options and indicated very good performance of amplified testing for detection of TV in symptomatic and asymptomatic women. PMID:27196258

  9. Rapid laser annealing of Cu(In,Ga)Se2 thin films by using a continuous wave Nd:YAG laser (λ0= 532 nm)

    Science.gov (United States)

    Kim, Nam-Hoon; Ko, Pil Ju; Cho, Geum-Bae; Park, Chan Il

    2017-04-01

    Rapid laser annealing of a Cu(In,Ga)Se2 (CIGS) thin film absorber was proposed and demonstrated using a continuous 532-nm Nd:YAG laser, following sputtering with Cu0.9In0.7Ga0.3Se2 target, because the conventional annealing temperature for improving the crystallinity of CIGS thin films is higher than the decomposition temperature of a typical flexible polymer substrate. When the laser optical power was incrementally increased over the range from 2.00 to 3.00 W, for 200 s, XRD patterns showed the formation of CIGS chalcopyrite (112), (220/204), and (312/116) phases in the laser-annealed CIGS thin films, at laser optical powers of 2.75 and 3.00 W. The band gaps of these laser-annealed CIGS thin films varied from 1.45 to 1.83 eV and depended on the laser optical power. The relative mean absorbance of the laser-annealed CIGS thin films was 1.806, suggesting that approximately 98.44% of the incident photons were observed by the 600-nm-thick film in the visible spectral region. Conductivity type varied with changes in the laser optical power. The resistivities of the laser-annealed CIGS thin films were of order of 10-3 - 101 Ω-cm.

  10. Development of a loop-mediated isothermal amplification assay for rapid, sensitive detection of Campylobacter jejuni in cattle farm samples.

    Science.gov (United States)

    Dong, Hee-Jin; Cho, Ae-Ri; Hahn, Tae-Wook; Cho, Seongbeom

    2014-09-01

    Campylobacter jejuni is a leading cause of bacterial foodborne disease worldwide. The detection of this organism in cattle and their environment is important for the control of C. jejuni transmission and the prevention of campylobacteriosis. Here, we describe the development of a rapid and sensitive method for the detection of C. jejuni in naturally contaminated cattle farm samples, based on real-time loop-mediated isothermal amplification (LAMP) of the hipO gene. The LAMP assay was specific (100% inclusivity and exclusivity for 84 C. jejuni and 41 non-C. jejuni strains, respectively), sensitive (detection limit of 100 fg/μl), and quantifiable (R(2) = 0.9133). The sensitivity of the LAMP assay was then evaluated for its application to the naturally contaminated cattle farm samples. C. jejuni strains were isolated from 51 (20.7%) of 246 cattle farm samples, and the presence of the hipO gene was tested using the LAMP assay. Amplification of the hipO gene by LAMP within 30 min (mean ~10.8 min) in all C. jejuni isolates (n = 51) demonstrated its rapidity and accuracy. Next, template DNA was prepared from a total of 186 enrichment broth cultures of cattle farm samples either by boiling or using a commercial kit, and the sensitivity of detection of C. jejuni was compared between the LAMP and PCR assays. In DNA samples prepared by boiling, the higher sensitivity of the LAMP assay (84.4%) compared with the PCR assay (35.5%) indicates that it is less susceptible to the existence of inhibitors in sample material. In DNA samples prepared using a commercial kit, both the LAMP and PCR assays showed 100% sensitivity. We anticipate that the use of this rapid, sensitive, and simple LAMP assay, which is the first of its kind for the identification and screening of C. jejuni in cattle farm samples, may play an important role in the prevention of C. jejuni contamination in the food chain, thereby reducing the risk of human campylobacteriosis.

  11. Multiple Endonuclease Restriction Real-Time Loop-Mediated Isothermal Amplification: A Novel Analytically Rapid, Sensitive, Multiplex Loop-Mediated Isothermal Amplification Detection Technique.

    Science.gov (United States)

    Wang, Yi; Wang, Yan; Lan, Ruiting; Xu, Huaqing; Ma, Aijing; Li, Dongxun; Dai, Hang; Yuan, Xuejiao; Xu, Jianguo; Ye, Changyun

    2015-07-01

    Loop-mediated isothermal amplification (LAMP) is restricted to detecting a single target, limiting the usefulness of this method. To achieve multiplex LAMP-based detection, we developed a novel approach we called the multiple endonuclease restriction real-time-LAMP assay. In this system, the LAMP forward or backward inner primers contain 5' end short sequences that are recognized by the restriction endonuclease Nb.BsrDI, and the new forward or backward inner primers were modified at the 5' end with a fluorophore and in the middle with a dark quencher. Nb.BsrDI digests the newly synthesized double-stranded terminal sequences (5' end short sequences and their complementary sequences), which releases the quenching, resulting in a gain of signal. The assay permitted real-time detection of single or multiple target sequences in a single tube, and the positive results can be obtained in as short as 12 minutes. The novel methodology is highly efficient and specific, detecting down to 250 fg of DNA per reaction of Listeria DNA tested, and was successful in evaluating raw meat samples. The multiple endonuclease restriction real-time-LAMP technology, which is an extension of LAMP to accommodate robust, target-specific, and multiplex detection, provides a molecular diagnostic tool with less detection time and high sensitivity and specificity compared with those of LAMP and quantitative real-time PCR. Copyright © 2015 American Society for Investigative Pathology and the Association for Molecular Pathology. Published by Elsevier Inc. All rights reserved.

  12. Practical biophysics: Sensors for rapid detection of biological targets utilizing target-induced oligonucleotide annealing.

    Science.gov (United States)

    Heyduk, Tomasz

    2010-10-01

    Detection and quantitation of biomolecules is one of the most commonly performed measurements in biomedical research and clinical diagnostics. There is high demand for convenient, rapid and sensitive biomolecule detection methodologies. In this review we discuss a family of sensors that have been developed in our laboratory that share a common simple biophysical mechanism of action and that are capable of rapid detection of a diverse range of biological targets. The sensors generate fluorescence signal in the presence of the target molecule through target-induced association of short fluorochrome-labeled complementary oligonucleotides that are attached to target recognition elements of the sensors (antibodies, aptamers, etc.) via nanometer scale flexible linkers. This sensor design can be used for detecting proteins, antibodies, nucleic acids and whole cells. The assays using these sensors require only adding a sample to the sensor mix followed by simple fluorescence intensity readout. The simplicity, the speed of detection and the potential for miniaturization are the main assets of these sensors. 2010 Elsevier B.V. All rights reserved.

  13. Rapid identification of drug-type strains in Cannabis sativa using loop-mediated isothermal amplification assay.

    Science.gov (United States)

    Kitamura, Masashi; Aragane, Masako; Nakamura, Kou; Watanabe, Kazuhito; Sasaki, Yohei

    2017-01-01

    In Cannabis sativa L., tetrahydrocannabinol (THC) is the primary psychoactive compound and exists as the carboxylated form, tetrahydrocannabinolic acid (THCA). C. sativa is divided into two strains based on THCA content-THCA-rich (drug-type) strains and THCA-poor (fiber-type) strains. Both strains are prohibited by law in many countries including Japan, whereas the drug-type strains are regulated in Canada and some European countries. As the two strains cannot be discriminated by morphological analysis, a simple method for identifying the drug-type strains is required for quality control in legal cultivation and forensic investigation. We have developed a novel loop-mediated isothermal amplification (LAMP) assay for identifying the drug-type strains of C. sativa. We designed two selective LAMP primer sets for on-site or laboratory use, which target the drug-type THCA synthase gene. The LAMP assay was accomplished within approximately 40 min. The assay showed high specificity for the drug-type strains and its sensitivity was the same as or higher than that of conventional polymerase chain reaction. We also showed the effectiveness of melting curve analysis that was conducted after the LAMP assay. The melting temperature values of the drug-type strains corresponded to those of the cloned drug-type THCA synthase gene, and were clearly different from those of the cloned fiber-type THCA synthase gene. Moreover, the LAMP assay with simple sample preparation could be accomplished within 1 h from sample treatment to identification without the need for special devices or techniques. Our rapid, sensitive, specific, and simple assay is expected to be applicable to laboratory and on-site detection.

  14. Evaluation of loop-mediated isothermal amplification for the rapid, reliable, and robust detection of Salmonella in produce.

    Science.gov (United States)

    Yang, Qianru; Wang, Fei; Jones, Kelly L; Meng, Jianghong; Prinyawiwatkul, Witoon; Ge, Beilei

    2015-04-01

    Rapid, reliable, and robust detection of Salmonella in produce remains a challenge. In this study, loop-mediated isothermal amplification (LAMP) was comprehensively evaluated against real-time quantitative PCR (qPCR) for detecting diverse Salmonella serovars in various produce items (cantaloupe, pepper, and several varieties of lettuce, sprouts, and tomato). To mimic real-world contamination events, produce samples were surface-inoculated with low concentrations (1.1-2.9 CFU/25 g) of individual Salmonella strains representing ten serovars and tested after aging at 4 °C for 48 h. Four DNA extraction methods were also compared using produce enrichment broths. False-positive or false-negative results were not observed among 178 strains (151 Salmonella and 27 non-Salmonella) used to evaluate assay specificity. The detection limits for LAMP were 1.8-4 CFU per reaction in pure culture and 10(4)-10(6) CFU per 25 g (i.e., 10(2)-10(4) CFU per g) in produce without enrichment, comparable to those obtained by qPCR. After 6-8 h of enrichment, both LAMP and qPCR consistently detected these low concentrations of Salmonella of diverse serovars in all produce items except sprouts. The PrepMan Ultra sample preparation reagent yielded the best results among the four DNA extraction methods. Upon further validation, LAMP may be a valuable tool for routine Salmonella testing in produce. The difficulty of detecting Salmonella in sprouts, whether using LAMP or qPCR, warrants further study. Published by Elsevier Ltd.

  15. Development and evaluation of rapid novel isothermal amplification assays for important veterinary pathogens: Chlamydia psittaci and Chlamydia pecorum

    Directory of Open Access Journals (Sweden)

    Martina Jelocnik

    2017-09-01

    Full Text Available Background Chlamydia psittaci and Chlamydia pecorum are important veterinary pathogens, with the former also being responsible for zoonoses, and the latter adversely affecting koala populations in Australia and livestock globally. The rapid detection of these organisms is still challenging, particularly at the point-of-care (POC. In the present study, we developed and evaluated rapid, sensitive and robust C. psittaci-specific and C. pecorum-specific Loop Mediated Isothermal Amplification (LAMP assays for detection of these pathogens. Methods and Materials The LAMP assays, performed in a Genie III real-time fluorometer, targeted a 263 bp region of the C. psittaci-specific Cps_0607 gene or a 209 bp region of a C. pecorum-specific conserved gene CpecG_0573, and were evaluated using a range of samples previously screened using species-specific quantitative PCRs (qPCRs. Species-specificity for C. psittaci and C. pecorum LAMP targets was tested against DNA samples from related chlamydial species and a range of other bacteria. In order to evaluate pathogen detection in clinical samples, C. psittaci LAMP was evaluated using a total of 26 DNA extracts from clinical samples from equine and avian hosts, while for C. pecorum LAMP, we tested a total of 63 DNA extracts from clinical samples from koala, sheep and cattle hosts. A subset of 36 C. pecorum samples was also tested in a thermal cycler (instead of a real-time fluorometer using newly developed LAMP and results were determined as an end point detection. We also evaluated rapid swab processing (without DNA extraction to assess the robustness of these assays. Results Both LAMP assays were demonstrated to species-specific, highly reproducible and to be able to detect as little as 10 genome copy number/reaction, with a mean amplification time of 14 and 24 min for C. psittaci and C. pecorum, respectively. When testing clinical samples, the overall congruence between the newly developed LAMP assays and q

  16. Development and evaluation of rapid novel isothermal amplification assays for important veterinary pathogens: Chlamydia psittaci and Chlamydia pecorum.

    Science.gov (United States)

    Jelocnik, Martina; Islam, Md Mominul; Madden, Danielle; Jenkins, Cheryl; Branley, James; Carver, Scott; Polkinghorne, Adam

    2017-01-01

    Chlamydia psittaci and Chlamydia pecorum are important veterinary pathogens, with the former also being responsible for zoonoses, and the latter adversely affecting koala populations in Australia and livestock globally. The rapid detection of these organisms is still challenging, particularly at the point-of-care (POC). In the present study, we developed and evaluated rapid, sensitive and robust C. psittaci-specific and C. pecorum-specific Loop Mediated Isothermal Amplification (LAMP) assays for detection of these pathogens. The LAMP assays, performed in a Genie III real-time fluorometer, targeted a 263 bp region of the C. psittaci-specific Cps_0607 gene or a 209 bp region of a C. pecorum-specific conserved gene CpecG_0573, and were evaluated using a range of samples previously screened using species-specific quantitative PCRs (qPCRs). Species-specificity for C. psittaci and C. pecorum LAMP targets was tested against DNA samples from related chlamydial species and a range of other bacteria. In order to evaluate pathogen detection in clinical samples, C. psittaci LAMP was evaluated using a total of 26 DNA extracts from clinical samples from equine and avian hosts, while for C. pecorum LAMP, we tested a total of 63 DNA extracts from clinical samples from koala, sheep and cattle hosts. A subset of 36 C. pecorum samples was also tested in a thermal cycler (instead of a real-time fluorometer) using newly developed LAMP and results were determined as an end point detection. We also evaluated rapid swab processing (without DNA extraction) to assess the robustness of these assays. Both LAMP assays were demonstrated to species-specific, highly reproducible and to be able to detect as little as 10 genome copy number/reaction, with a mean amplification time of 14 and 24 min for C. psittaci and C. pecorum, respectively. When testing clinical samples, the overall congruence between the newly developed LAMP assays and qPCR was 92.3% for C. psittaci (91.7% sensitivity and 92

  17. Development of a rapid loop-mediated isothermal amplification assay for diagnosis and assessment of cure of Leishmania infection.

    Science.gov (United States)

    Verma, Sandeep; Singh, Ruchi; Sharma, Vanila; Bumb, Ram Avtar; Negi, Narendra Singh; Ramesh, V; Salotra, Poonam

    2017-03-23

    Leishmaniasis is a spectrum of diseases with great relevance to public health. Conventional diagnostic methods are time consuming, needing trained personnel. A robust, rapid and cost effective diagnostic test is warranted for on-time diagnosis and field application. We have developed a loop mediated isothermal amplification (LAMP) assay with primers (n = 6) based on Leishmania donovani kDNA for detection of Leishmania infection, using a closed tube to prevent cross-contamination. The assay was used to detect Leishmania infection in biological samples obtained from patients of visceral leishmaniasis (VL), post kala-azar dermal leishmaniasis (PKDL) and cutaneous leishmaniasis (CL). The assay was positive for L. donovani, L. tropica and L. major parasites, with the highest sensitivity towards L. donovani (1 fg DNA). The high sensitivity of the assay for detection of L. donovani was reflected in its ability to detect parasite DNA within 30 min of amplification time with a threshold detection limit of ≥25 copies per reaction. The assay detected parasite in 64 of 66 VL blood samples (sensitivity, 96.9%; 95% CI: 89.6-99.2%), 15 of 15 VL bone marrow aspirate samples (sensitivity, 100%; 95% CI:79.6-100%), 65 of 67 PKDL tissue biopsy samples (sensitivity, 97%; 95% CI:89.7-99.2%). The assay was evaluated in a few cases of CL wherein it was found positive in 8 of 10 tissue biopsies (sensitivity, 80%; 95% CI: 49-94.3%). The assay was negative in all control blood (n = 76) and tissue biopsy (n = 24) samples (specificity, 100%; 95% CI: 96.3-100%). Further, the assay was evaluated for its utility in assessment of cure in treated VL and PKDL patients. The assay detected parasite DNA in 2 of 20VL blood samples and 2 of 21 PKDL tissue samples. Out of 4 cases that were positive for parasite DNA at post treatment stage, 2 patients (1VL and 1 PKDL) returned with relapse. The study demonstrated a Leishmania genus specific closed tube LAMP assay for reliable and rapid

  18. Rapid, simple and sensitive detection of Q fever by loop-mediated isothermal amplification of the htpAB gene.

    Directory of Open Access Journals (Sweden)

    Lei Pan

    Full Text Available BACKGROUND: Q fever is the most widespread zoonosis, and domestic animals are the most common sources of transmission. It is not only difficult to distinguish from other febrile diseases because of the lack of specific clinical manifestations in humans, but it is also difficult to identify the disease in C. burnetii-carrying animals because of the lack of identifiable features. Conventional serodiagnosis requires sera from the acute and convalescent stages of infection, which are unavailable at early diagnosis. Nested PCR and real-time PCR require equipment. In this study, we developed a Loop-Mediated Isothermal Amplification (LAMP assay to identify C. burnetii rapidly and sensitively. METHODS: A universal LAMP primer set was designed to detect the repeated sequence IS1111a of the htpAB gene of C. burnetii using PrimerExplorer V4 software. The sensitivity of the LAMP assay was evaluated using known quantities of recombined reference plasmids containing the targeted genes. The specificity of the developed LAMP assay was determined using 26 members of order Rickettsiae and 18 other common pathogens. The utility of the LAMP assay was further compared with real time PCR by the examination 24 blood samples including 6 confirmed and 18 probable Q fever cases, which diagnosed by IFA serological assessment and real time PCR. In addition, 126 animal samples from 4 provinces including 97 goats, 7 cattle, 18 horses, 3 marmots and 1 deer were compared by these two methods. RESULTS: The limits of detection of the LAMP assay for the htpAB gene were 1 copy per reaction. The specificity of the LAMP assay was 100%, and no cross-reaction was observed among the bacteria used in the study. The positive rate of unknown febrile patients was 33.3%(95%CI 30.2%-36.4% for the LAMP assay and 8.3%(95%CI 7.4%-9.2% for the real time PCR(P<0.05. Similarly, the total positive rate of animals was 7.9%(95%CI 7.1%-8.7% for the LAMP assay and 0.8%(95%CI 0.7%-0.9%for the real time

  19. Rapid detection of Salmonella in food and feed by coupling loop-mediated isothermal amplification with bioluminescent assay in real-time

    OpenAIRE

    Yang, Qianru; Domesle, Kelly J; Wang, Fei; Ge, Beilei

    2016-01-01

    Background Salmonella is among the most significant pathogens causing food and feed safety concerns. This study examined the rapid detection of Salmonella in various types of food and feed samples by coupling loop-mediated isothermal amplification (LAMP) with a novel reporter, bioluminescent assay in real-time (BART). Performance of the LAMP-BART assay was compared to a conventional LAMP and the commercially available 3M Molecular Detection Assay (MDA) Salmonella. Results The LAMP-BART assay ...

  20. A lab-on-a-chip system with integrated sample preparation and loop-mediated isothermal amplification for rapid and quantitative detection of Salmonella spp. in food samples.

    Science.gov (United States)

    Sun, Yi; Quyen, Than Linh; Hung, Tran Quang; Chin, Wai Hoe; Wolff, Anders; Bang, Dang Duong

    2015-04-21

    Foodborne disease is a major public health threat worldwide. Salmonellosis, an infectious disease caused by Salmonella spp., is one of the most common foodborne diseases. Isolation and identification of Salmonella by conventional bacterial culture or molecular-based methods are time consuming and usually take a few hours to days to complete. In response to the demand for rapid on line or on site detection of pathogens, in this study, we describe for the first time an eight-chamber lab-on-a-chip (LOC) system with integrated magnetic bead-based sample preparation and loop-mediated isothermal amplification (LAMP) for rapid and quantitative detection of Salmonella spp. in food samples. The whole diagnostic procedures including DNA isolation, isothermal amplification, and real-time detection were accomplished in a single chamber. Up to eight samples could be handled simultaneously and the system was capable to detect Salmonella at concentration of 50 cells per test within 40 min. The simple design, together with high level of integration, isothermal amplification, and quantitative analysis of multiple samples in short time, will greatly enhance the practical applicability of the LOC system for rapid on-site screening of Salmonella for applications in food safety control, environmental surveillance, and clinical diagnostics.

  1. The effect of rapid thermal annealing on the photoluminescence of InAsN/InGaAs dot-in-a-well structures

    Energy Technology Data Exchange (ETDEWEB)

    Gargallo-Caballero, R; Miguel-Sanchez, J; Guzman, A; Hierro, A; Munoz, E [Instituto de Sistemas Optoelectronicos y MicrotecnologIa (ISOM)-Departamento de IngenierIa Electronica, ETSI Telecomunicacion, Universidad Politecnica de Madrid, Ciudad Universitaria s/n, 28040 Madrid (Spain)], E-mail: rgargallo@die.upm.es

    2008-03-21

    The effect of post-growth rapid thermal annealing on the optical characteristics of InAsN/InGaAs dot-in-a-well DWELL structures grown by molecular beam epitaxy on GaAs(1 0 0) has been studied. InAs/InGaAs DWELL structures have been used as a reference. Photoluminescence measurements of these samples show similar optical effects, such as a blueshift of the peak wavelength and a reduction of the full width of at half maximum PL emission, in both types of structures up to an annealing temperature of 750 deg. C. Nevertheless, at 850 deg. C, these effects are much more pronounced in the structures with N. These results suggest that an additional As-N interdiffusion process inside the InAsN quantum dots plays a dominant role in these effects at high annealing temperatures (850 deg. C) on InAsN/InGaAs structures.

  2. Effect of Annealing on the Microstructure of Rapidly Solidified Foils of Alloy Bi50Sn35In15

    Science.gov (United States)

    Shepelevich, V. G.; Shcherbachenko, L. P.

    2016-07-01

    The effect of annealing on the microstructure of foils of alloy Bi50Sn35In15 is studied. It is shown that prolongation of the annealing time is accompanied by coarsening of the structure, which reduces the specific surface of the interfaces virtually without changing the volume fractions of the phases.

  3. Investigations of rapid thermal annealing induced structural evolution of ZnO: Ge nanocomposite thin films via GISAXS

    Energy Technology Data Exchange (ETDEWEB)

    Ceylan, Abdullah, E-mail: aceylanabd@yahoo.com [Department of Physics Eng., Hacettepe University, Beytepe, 06800 Ankara (Turkey); Ozcan, Yusuf [Department of Electricity and Energy, Pamukkale University, Denizli (Turkey); Orujalipoor, Ilghar [Department of Nanotechnology and Nanomedicine, Hacettepe University, Beytepe, 06800 Ankara (Turkey); Huang, Yen-Chih; Jeng, U-Ser [National Synchrotron Radiation Research Center, 101 Hsin-Ann Road, Hsinchu Science Park, Hsinchu, Taiwan (China); Ide, Semra [Department of Physics Eng., Hacettepe University, Beytepe, 06800 Ankara (Turkey); Department of Nanotechnology and Nanomedicine, Hacettepe University, Beytepe, 06800 Ankara (Turkey)

    2016-06-07

    In this work, we present in depth structural investigations of nanocomposite ZnO: Ge thin films by utilizing a state of the art grazing incidence small angle x-ray spectroscopy (GISAXS) technique. The samples have been deposited by sequential r.f. and d.c. sputtering of ZnO and Ge thin film layers, respectively, on single crystal Si(100) substrates. Transformation of Ge layers into Ge nanoparticles (Ge-np) has been initiated by ex-situ rapid thermal annealing of asprepared thin film samples at 600 °C for 30, 60, and 90 s under forming gas atmosphere. A special attention has been paid on the effects of reactive and nonreactive growth of ZnO layers on the structural evolution of Ge-np. GISAXS analyses have been performed via cylindrical and spherical form factor calculations for different nanostructure types. Variations of the size, shape, and distributions of both ZnO and Ge nanostructures have been determined. It has been realized that GISAXS results are not only remarkably consistent with the electron microscopy observations but also provide additional information on the large scale size and shape distribution of the nanostructured components.

  4. Dependence of N incorporation into (Ga)InAsN QDs on Ga content probed by rapid thermal annealing

    Energy Technology Data Exchange (ETDEWEB)

    Gargallo-Caballero, R.; Guzman, A.; Ulloa, J.M.; Hierro, A.; Calleja, E. [Instituto de Sistemas Optoelectronicos y Microtecnologia (ISOM) - Departamento de Ingenieria Electronica, ETSI Telecomunicacion, Universidad Politecnica de Madrid (Spain); Hopkinson, M. [Department of Electronic and Electrical Engineering, EPSRC National Centre for III-V Technologies, University of Sheffield (United Kingdom)

    2009-06-15

    In this letter we demonstrate that the N incorporation into (Ga)InAsN quantum dots (QDs), grown on GaAs (100) by radio-frequency (RF) plasma assisted molecular beam epitaxy (MBE), is enhanced as the Ga content increases up to 30% and decreases for Ga contents higher than 30%. Thus, this effect exhibits a maximum N incorporation with a Ga content of 30%. Two sets of (Ga)InAsN QDs samples have been grown under the same growth conditions but with different N contents in one of them and with different Ga concentration in the other set. Optical analysis using Photoluminescence (PL) measurements of the as-grown and post growth rapid thermal annealed samples have been performed. The experimental results show a clear increase of the blueshift with the N concentration as occurred in dilute nitride quantum well (QW) structures. PL peak emission wavelength as high as 1.55{mu}m has been obtained from QDs capped with GaAs. (copyright 2009 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  5. Effects of Rapid Thermal Annealing on the Structural, Electrical, and Optical Properties of Zr-Doped ZnO Thin Films Grown by Atomic Layer Deposition

    Directory of Open Access Journals (Sweden)

    Jingjin Wu

    2016-08-01

    Full Text Available The 4 at. % zirconium-doped zinc oxide (ZnO:Zr films grown by atomic layer deposition (ALD were annealed at various temperatures ranging from 350 to 950 °C. The structural, electrical, and optical properties of rapid thermal annealing (RTA treated ZnO:Zr films have been evaluated to find out the stability limit. It was found that the grain size increased at 350 °C and decreased between 350 and 850 °C, while creeping up again at 850 °C. UV–vis characterization shows that the optical band gap shifts towards larger wavelengths. The Hall measurement shows that the resistivity almost keeps constant at low annealing temperatures, and increases rapidly after treatment at 750 °C due to the effect of both the carrier concentration and the Hall mobility. The best annealing temperature is found in the range of 350–550 °C. The ZnO:Zr film-coated glass substrates show good optical and electrical performance up to 550 °C during superstrate thin film solar cell deposition.

  6. Structural stability of hydrogenated amorphous carbon overcoats used in heat-assisted magnetic recording investigated by rapid thermal annealing

    KAUST Repository

    Wang, N.

    2013-01-01

    Ultrathin amorphous carbon (a-C) films are extensively used as protective overcoats of magnetic recording media. Increasing demands for even higher storage densities have necessitated the development of new storage technologies, such as heat-assisted magnetic recording (HAMR), which uses laser-assisted heating to record data on high-stability media that can store single bits in extremely small areas (∼1 Tbit/in.2). Because HAMR relies on locally changing the coercivity of the magnetic medium by raising the temperature above the Curie temperature for data to be stored by the magnetic write field, it raises a concern about the structural stability of the ultrathin a-C film. In this study, rapid thermal annealing (RTA) experiments were performed to examine the thermal stability of ultrathin hydrogenated amorphous carbon (a-C:H) films deposited by plasma-enhanced chemical vapor deposition. Structural changes in the a-C:H films caused by RTA were investigated by x-ray photoelectron spectroscopy, Raman spectroscopy, x-ray reflectivity, and conductive atomic force microscopy. The results show that the films exhibit thermal stability up to a maximum temperature in the range of 400-450 °C. Heating above this critical temperature leads to hydrogen depletion and sp 2 clustering. The critical temperature determined by the results of this study represents an upper bound of the temperature rise due to laser heating in HAMR hard-disk drives and the Curie temperature of magnetic materials used in HAMR hard disks. © 2013 American Institute of Physics.

  7. Rapid and visual detection of human enterovirus coxsackievirus A16 by reverse transcription loop-mediated isothermal amplification combined with lateral flow device.

    Science.gov (United States)

    Yan, G; Jun, L; Kangchen, Z; Yiyue, G; Yang, Y; Xiaoyu, Z; Zhiyang, S; Lunbiao, C

    2015-12-01

    In this study, a reverse transcription loop-mediated isothermal amplification (RT-LAMP) combined with lateral flow device (LFD) technology to rapidly detect CVA16 was developed and evaluated. RT-LAMP assay was optimized to amplify VP1 gene of CVA16. Amplified products were analysed by LFD and capillary electrophoresis. The RT-LAMP-LFD assay showed 100% specificity in detecting CVA16, and showed analytical sensitivity of 0·55 TCID50 per reaction mixture. Comparison of the RT-LAMP-LFD assay with real-time RT-PCR developed previously in clinical specimens showed 93·3% agreement. The RT-LAMP-LFD assay is more sensitive in detecting CVA16 RNA. The RT-LAMP-LFD assay presented here might offer a rapid and simple alternative in clinical diagnosis of CVA16. Coxsackievirus A16 (CVA16) is one of the major causative agents of hand, foot and mouth disease (HFMD). Rapid and reliable detection and typing of it can limit the spread. We developed a reverse transcription loop-mediated isothermal amplification (RT-LAMP) combined with lateral flow device (LFD) technology to rapidly detect CVA16. The high sensitivity and specificity and its ease of use make this assay ideal for use in resource-limited settings such as primary care facilities and clinical laboratories in developing countries. © 2015 The Society for Applied Microbiology.

  8. Effects of rapid thermal annealing on two-dimensional delocalized electronic states of the epitaxial N δ-doped layer in GaAs

    Energy Technology Data Exchange (ETDEWEB)

    Ogawa, Yasuhiro; Harada, Yukihiro; Baba, Takeshi; Kaizu, Toshiyuki; Kita, Takashi [Department of Electrical and Electronic Engineering, Graduate School of Engineering, Kobe University, 1-1 Rokkodai, Nada, Kobe 657-8501 (Japan)

    2016-03-14

    We have conducted rapid thermal annealing (RTA) for improving the two-dimensional (2D) arrangement of electronic states in the epitaxial nitrogen (N) δ-doped layer in GaAs. RTA rearranged the N-pair configurations in the GaAs (001) plane and reduced the number of non-radiative recombination centers. Furthermore, a Landau shift, representing the 2D delocalized electronic states in the (001) plane, was observed at around zero magnetic field intensity in the Faraday configuration.

  9. Evaluation of a Fully Automated Analyzer for Rapid Measurement of Water Vapor Sorption Isotherms for Applications in Soil Science

    DEFF Research Database (Denmark)

    Arthur, Emmanuel; Tuller, Markus; Moldrup, Per

    2014-01-01

    The characterization and description of important soil processes such as water vapor transport, volatilization of pesticides, and hysteresis require accurate means for measuring the soil water characteristic (SWC) at low water potentials. Until recently, measurement of the SWC at low water...... sorption isotherms. In this technical note we present a comprehensive evaluation of the VSA instrument for a wide range of differently textured soils and discuss optimal measurement settings. The effects of operation mode, air-flow rate, sample pretreatment, test temperature, sample mass, and mass trigger...... point on resultant sorption isotherms were evaluated for a relative humidity range from 0.10 to 0.90. Both adsorption and desorption branches were measured for all soils within a reasonable time period (10 – 50 h). Sample masses larger than 3.5 g resulted in incomplete adsorption and desorption, while...

  10. Effect of rapid thermal annealing on the Mo back contact properties for Cu{sub 2}ZnSnSe{sub 4} solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Placidi, Marcel, E-mail: mplacidi@irec.cat [Catalonia Institute for Energy Research (IREC), Jardins de les Dones de Negre 1, pl.2, 08930 St Adrià del Besòs, Barcelona (Spain); Espindola-Rodriguez, Moises; Lopez-Marino, Simon; Sanchez, Yudania; Giraldo, Sergio; Acebo, Laura; Neuschitzer, Markus [Catalonia Institute for Energy Research (IREC), Jardins de les Dones de Negre 1, pl.2, 08930 St Adrià del Besòs, Barcelona (Spain); Alcobé, Xavier [Centres Científics i Tecnològics (CCiTUB), Lluis Solé i Sabarís 1, 08028 Barcelona (Spain); Pérez-Rodríguez, Alejandro [Catalonia Institute for Energy Research (IREC), Jardins de les Dones de Negre 1, pl.2, 08930 St Adrià del Besòs, Barcelona (Spain); IN2UB, Departament d’Electrònica, Universitat de Barcelona, Martí i Franquès 1, 08028 Barcelona (Spain); Saucedo, Edgardo [Catalonia Institute for Energy Research (IREC), Jardins de les Dones de Negre 1, pl.2, 08930 St Adrià del Besòs, Barcelona (Spain)

    2016-08-05

    The effect of a rapid thermal process (RTP) on the molybdenum (Mo) back contact for Cu{sub 2}ZnSnSe{sub 4} (CZTSe) solar cells is here investigated. It is shown that the annealing of the Mo layer during 5 min at 550 °C, not only improves the crystalline quality of the back contact (avoiding the absorber decomposition at this region because Mo becomes more resistant to the selenization), but also helps achieving higher crystalline quality of the absorber with bigger grains, reducing the current leakage through the heterojunction. We demonstrate that this is related to the relaxation of the compressive stress of the CZTSe absorber, when synthesized on the RTP annealed substrates. CZTSe solar cells prepared on annealed Mo films exhibited higher short circuit current densities and higher open circuit voltages, resulting in 10% and 33% higher fill factors and efficiencies. - Highlights: • An RTP annealing applied for the first time on Mo for CZTSe solar cells. • Clear improvement of the efficiency from 5.7 to 7.6% with RTP treatment. • Discussion of this improvement with adequate material/device characterizations. • Stress-induced defects responsible of the electrical leakage are revealed.

  11. Rapid and sensitive detection of Laem-Singh virus by reverse transcription loop-mediated isothermal amplification combined with a lateral flow dipstick.

    Science.gov (United States)

    Arunrut, Narong; Seetang-Nun, Yortyot; Phromjai, Jurairat; Panphut, Wattana; Kiatpathomchai, Wansika

    2011-10-01

    Laem-Singh virus (LSNV) was discovered recently in Thailand in farmed Giant Tiger shrimp (Penaeus monodon) displaying signs of slow growth syndrome. Loop-mediated isothermal amplification (LAMP) allows DNA to be amplified rapidly at a constant temperature. Here a reverse transcription (RT)-LAMP method was combined with a chromatographic lateral-flow dipstick (LFD) to detect LSNV RNA rapidly and specifically. The reaction was optimized at 65°C for 30 min and amplified DNA hybridized to an FITC-labeled oligonucleotide probe for 5 min was detected at LFD test line 5 min after application. Including 10 min for rapid RNA extraction, test results could be generated within 1h and did not require electrophoresis. Compared to an existing RT-PCR method, the RT-LAMP-LFD was also ∼1000-fold more sensitive in detecting LSNV RNA. Copyright © 2011 Elsevier B.V. All rights reserved.

  12. Specific, Sensitive, and Rapid Diagnosis of Active Toxoplasmosis by a Loop-Mediated Isothermal Amplification Method Using Blood Samples from Patients ▿

    OpenAIRE

    Lau, Yee Ling; Meganathan, Puviarasi; Sonaimuthu, Parthasarathy; Thiruvengadam, Girija; Nissapatorn, Veeranoot; Chen, Yeng

    2010-01-01

    Loop-mediated isothermal amplification (LAMP), a rapid nucleic acid amplification method, was developed for the clinical diagnosis of toxoplasmosis. Three LAMP assays based on the SAG1, SAG2, and B1 genes of Toxoplasma gondii were developed. The sensitivities and specificities of the LAMP assays were evaluated by comparison with the results of conventional nested PCR. The LAMP assays were highly sensitive and had a detection limit of 0.1 tachyzoite, and no cross-reactivity with the DNA of oth...

  13. Correlating the silicon surface passivation to the nanostructure of low-temperature a-Si:H after rapid thermal annealing

    Science.gov (United States)

    Macco, Bart; Melskens, Jimmy; Podraza, Nikolas J.; Arts, Karsten; Pugh, Christopher; Thomas, Owain; Kessels, Wilhelmus M. M.

    2017-07-01

    Using an inductively coupled plasma, hydrogenated amorphous silicon (a-Si:H) films have been prepared at very low temperatures (growth. The correlation between the a-Si:H nanostructure and the activation of a-Si:H/c-Si interface passivation, upon annealing, has been studied in detail. This yields a structural model that qualitatively describes the different processes that take place in the a-Si:H films during annealing. The presented experimental findings and insights can prove to be useful in the further development of very thin a-Si:H passivation layers for use in silicon heterojunction solar cells.

  14. Rapid thermal annealing of p-type silicon: Correlation between deep-level transient spectroscopy and lifetime measurements

    Science.gov (United States)

    Poggi, Antonella; Susi, Enrichetta; Bumuri, Maria Angela; Carotta, Maria Cristina

    1994-03-01

    The correlation between minority carrier lifetime and deep-level transient spectroscopy measurements was used in order to obtain more information about the mechanisms of defect formation and annealing in CS and FZ silicon during high temperature heating by lamp. Different energy levels induced by lamp annealings were detected: a good correlation with the lifetime behavior was observed of a donor at E(sub v) + 0.29 eV. No direct influence of the oxygen content was detected at 1050 C, while at 750 C a gettering action of oxygen aggregates can be hypothesized.

  15. Rapid thermal annealing and modulation-doping effects on InAs/GaAs quantum dots photoluminescence dependence on excitation power

    Energy Technology Data Exchange (ETDEWEB)

    Chaâbani, W. [Laboratoire Matériaux-Molécules et Applications, Institut Préparatoire aux Etudes Scientifiques et Techniques, Université de Carthage, La Marsa 2070 (Tunisia); Melliti, A., E-mail: adnenmelliti@yahoo.fr [Laboratoire Matériaux-Molécules et Applications, Institut Préparatoire aux Etudes Scientifiques et Techniques, Université de Carthage, La Marsa 2070 (Tunisia); Maaref, M.A. [Laboratoire Matériaux-Molécules et Applications, Institut Préparatoire aux Etudes Scientifiques et Techniques, Université de Carthage, La Marsa 2070 (Tunisia); Testelin, C. [Institut des NanoSciences de Paris, UPMC Univ., Paris 06, UMR 7588, F-75005 Paris (France); CNRS, UMR 7588, INSP, F-75005 Paris (France); Lemaître, A. [Laboratoire de Photonique et Nanostructures (LPN), CNRS, Route de Nozay, F-91460 Marcoussis (France)

    2016-07-15

    The optical properties of p-doped and annealed InAs/GaAs quantum dots (QDs) was investigated by photoluminescence (PL) as a function of temperature and excitation power density (P{sub exc}). At low-T, PL spectra of rapid thermal annealing (RTA) and p-modulation doped QDs show an energy blueshift and redshift, respectively. A superlinear dependence of integrated PL intensity on P{sub exc} at high-T was found only for undoped QD. The superlinearity was suppressed by modulation-doping and RTA effects. A linear dependence of I{sub PL} at all temperatures and a decrease of the carrier-carrier Coulomb interaction at high-T was found after RTA.

  16. A Large-Area Nanoplasmonic Sensor Fabricated by Rapid Thermal Annealing Treatment for Label-Free and Multi-Point Immunoglobulin Sensing.

    Science.gov (United States)

    Lin, Hana Tzu-Han; Yang, Chuan-Kai; Lin, Chi-Chen; Wu, Albert Meng-Hsin; Wang, Lon A; Huang, Nien-Tsu

    2017-05-02

    Immunoglobulins are important biomarkers to evaluate the immune status or development of infectious diseases. To provide timely clinical treatments, it is important to continuously monitor the level of multiple immunoglobulins. Localized surface plasmon resonance (LSPR)-based nanoplasmonic sensors have been demonstrated for multiplex immunoglobulins detection. However, the sensor fabrication process is usually slow and complicated, so it is not accessible for large-area and batch fabrication. Herein, we report a large-area (2 cm × 2 cm) nanofabrication method using physical vapor deposition followed by a rapid thermal annealing treatment. To optimize the sensor performance, we systematically characterized three fabrication conditions, including (1) the deposition thickness; (2) the maximum annealing temperature, and (3) the annealing time. The corresponding absorbance spectrum profile and surface morphology of the nanostructures were observed by a UV-VIS spectrometer and atomic force microscopy. We then tested the sensitivity of the sensor using a glucose solution at different concentrations. The results showed that the sensor with 10 nm gold deposition thickness under 5-min 900 °C rapid thermal annealing can achieve the highest sensitivity (189 nm RIU-1). Finally, we integrated this nanoplasmonic sensor with a microchannel and a motorized stage to perform a 10-spot immunoglobulin detection in 50 min. Based on its real-time, dynamic and multi-point analyte detection capability, the nanoplasmonic sensor has the potential to be applied in high-throughput or multiplex immunoassay analysis, which would be beneficial for disease diagnosis or biomedical research in a simple and cost-effective platform.

  17. Rapid detection of Bombyx mori nucleopolyhedrovirus (BmNPV) by loop-mediated isothermal amplification assay combined with a lateral flow dipstick method.

    Science.gov (United States)

    Zhou, Yang; Wu, Jiege; Lin, Feng; Chen, Naifu; Yuan, Shaofei; Ding, Lina; Gao, Li; Hang, Bangxing

    2015-12-01

    The Bombyx mori nucleopolyhedrovirus (BmNPV) is a principal pathogen of the domestic silkworm. The disease often breaks out in sericultural countries and due to its high infectivity; it is difficult to control, resulting in heavy economic loss. In order to develop a rapid, sensitive visual detection and simple-to-use novel technology for detection of BmNPV, a loop-mediated isothermal amplification (LAMP) assay combined with a lateral flow dipstick (LFD) method was described. In this study, a set of four primers and a labeled probe were designed specifically to recognize six distinct regions of the BmNPV gp41 gene, and the LAMP for the detection of BmNPV was developed by isothermal amplification at 61 °C for 45 min, followed by hybridization with an FITC-labeled DNA probe for 5 min and detected by LFD within 5 min. The detection limit of LAMP-LFD was 0.2 pg DNA extracted from silkworm infected with BmNPV and was 100 times more sensitive than conventional PCR. No product was generated from silkworm infected with other viruses. Furthermore, we applied the technique to detect BmNPV in the hemolymph and feces at different intervals post infection (pi). In conclusion, the novel LAMP-LFD setup presented here is simple, rapid, reliable, and has the potential for future use in the detection of BmNPV. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Development of a fluorescent-intercalating-dye-based reverse transcription loop-mediated isothermal amplification assay for rapid detection of seasonal Japanese B encephalitis outbreaks in pigs.

    Science.gov (United States)

    Tian, C J; Lin, Z X; He, X M; Luo, Q; Luo, C B; Yu, H Q; Chen, R; Wu, X W; Zhu, D Z; Ren, Z J; Bi, Y Z; Ji, J

    2012-08-01

    The standardization and validation of a one-step, single-tube, accelerated fluorescent-intercalating-dye-based reverse transcription loop-mediated isothermal amplification (RT-LAMP) assay targeting the NS3 gene of Japanese B encephalitis virus (JEV) is described for rapid, simple, and high-throughput detection of JEV. The amplification can be completed in 35 min under isothermal conditions at 63°C by employing a set of six primers targeting the NS3 gene of JEV. The RT-LAMP assay described demonstrated high sensitivity for detecting JEV, with a detection limit in swine samples of 8.13 PFU/ml. The specificity of the selected primer sets was established by cross-reactivity studies with pathogens that exhibit similar clinical signs and testing of samples from healthy animals. The clinical applicability of the RT-LAMP assay was validated using either spiked samples or samples from seasonal outbreaks. The comparative evaluation of the RT-LAMP assay revealed 79.59 % concordance with conventional RT-PCR targeting the E gene of JEV. The RT-LAMP assay reported here is a valuable tool for rapid real-time and high-throughput seasonal infection surveillance and quarantine after outbreak through blood sampling by using ordinary real-time PCR thermocyclers without purchasing an expensive Loopamp real-time turbidimeter.

  19. Electrical characteristics and interfacial reactions of rapidly annealed Pt/Ru Schottky contacts on n-type GaN

    Energy Technology Data Exchange (ETDEWEB)

    Reddy, N.N.K.; Rajagopal Reddy, V. [Department of Physics, Sri Venkateswara University, Tirupati (India); Choi, C.J. [School of Semiconductor and Chemical Engineering, Semiconductor Physics Research Center (SPRC), Chonbuk National University, Jeonju (Korea, Republic of)

    2011-07-15

    The electrical properties and interfacial reactions of Pt/Ru Schottky contacts on n-type gallium nitride (GaN) have been investigated as a function of annealing temperature. The calculated Schottky barrier height (SBH) of the as-deposited Pt/Ru Schottky contact is found to be 0.69 eV current-voltage (I-V) and 0.76 eV capacitance-voltage (C-V). Experimental results showed that the SBHs are increased on increasing the annealing temperature. When the contact is annealed at 600 C, a maximum barrier height is obtained and the corresponding values are 0.87 eV (I-V) and 0.99 eV (C-V). The Norde method was also employed to extract the barrier height of Pt/Ru Schottky contacts and the values are 0.70 and 0.86 eV for the samples as-deposited and annealed at 600 C, which are in good agreement with those obtained from the I-V measurement. Shifts of the surface Fermi level are measured with the change in position of the Ga 2p core level peak. Based on the X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) studies, the formation of gallide phases at the Ru/Pt/n-GaN interface could be the reason for the increase in SBH at elevated temperatures. Atomic force microscopy (AFM) results showed that the surface morphology of the Pt/Ru Schottky contact did not change significantly even after annealing at 600 C. These results point out that a Pt/Ru Schottky contact may be a suitable candidate for the fabrication of GaN-based high-temperature device applications. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  20. Rapid in vitro splicing of coding sequences from genomic DNA by isothermal recombination reaction-based PCR

    Directory of Open Access Journals (Sweden)

    Wenxuan Chen

    2016-09-01

    Full Text Available Cloning of coding sequence (CDS is an important step for gene function research. Here, we reported a simple and efficient strategy for assembling multiple-exon into an intron-free CDS from genomic DNA (gDNA by an isothermal recombination reaction-based PCR (IRR-PCR method. As an example, a 2067-bp full-length CDS of the anther-specific expression gene OsABCG15, which is composed of seven exons and six introns, was generated by IRR-PCR using genomic DNA of rice leaf as the template. Actually, this approach can be wildly applied to any DNA sequences assembly to achieve CDS cloning, gene fusion and multiple site-directed mutagenesis in functional genomics studies in vitro.

  1. Specific, sensitive and rapid detection of human plasmodium knowlesi infection by loop-mediated isothermal amplification (LAMP in blood samples

    Directory of Open Access Journals (Sweden)

    Anthony Claudia N

    2011-07-01

    Full Text Available Abstract Background The emergence of Plasmodium knowlesi in humans, which is in many cases misdiagnosed by microscopy as Plasmodium malariae due to the morphological similarity has contributed to the needs of detection and differentiation of malaria parasites. At present, nested PCR targeted on Plasmodium ssrRNA genes has been described as the most sensitive and specific method for Plasmodium detection. However, this method is costly and requires trained personnel for its implementation. Loop-mediated isothermal amplification (LAMP, a novel nucleic acid amplification method was developed for the clinical detection of P. knowlesi. The sensitivity and specificity of LAMP was evaluated in comparison to the results obtained via microscopic examination and nested PCR. Methods LAMP assay was developed based on P. knowlesi genetic material targeting the apical membrane antigen-1 (AMA-1 gene. The method uses six primers that recognize eight regions of the target DNA and it amplifies DNA within an hour under isothermal conditions (65°C in a water-bath. Results LAMP is highly sensitive with the detection limit as low as ten copies for AMA-1. LAMP detected malaria parasites in all confirm cases (n = 13 of P. knowlesi infection (sensitivity, 100% and none of the negative samples (specificity, 100% within an hour. LAMP demonstrated higher sensitivity compared to nested PCR by successfully detecting a sample with very low parasitaemia ( Conclusion With continuous efforts in the optimization of this assay, LAMP may provide a simple and reliable test for detecting P. knowlesi malaria parasites in areas where malaria is prevalent.

  2. Rapid thermal annealing effect on the spatial resistivity distribution of AZO thin films deposited by pulsed-direct-current sputtering for solar cells applications

    Energy Technology Data Exchange (ETDEWEB)

    Ayachi, Boubakeur, E-mail: boubakeur.ayachi@ed.univ-lille1.fr [Institute of Electronics, Microelectronics and Nanotechnology, Lille 1 University, Avenue Poincaré, UMR 8520, CS 60069, Villeneuve d’Ascq 59652 (France); Aviles, Thomas [CROSSLUX, Avenue Georges Vacher, ZI Rousset Peynier, Immeuble CCE, Rousset 13106 (France); Vilcot, Jean-Pierre [Institute of Electronics, Microelectronics and Nanotechnology, Lille 1 University, Avenue Poincaré, UMR 8520, CS 60069, Villeneuve d’Ascq 59652 (France); Sion, Cathy [Institute of Electronics, Microelectronics and Nanotechnology, Lille 1 University, Avenue Poincaré, UMR 8520, CS 60069, Villeneuve d’Ascq 59652 (France); Ecole Centrale Lille, Cité Scientifique – CS20048, Villeneuve d’Ascq 59651 (France)

    2016-03-15

    Graphical abstract: - Highlights: • High quality pulsed-DC sputtered AZO thin films were obtained after RTA treatment. • RTA for 30 s was sufficient to achieve uniform spatial resistivity distribution. • RTA for longer than 1 min showed a small increase in resistivity value. • Such improvement was attributed to grain boundaries passivation and doping activation. • In the framework of low cost solar cells development, RTA process would be helpful. - Abstract: Room temperature deposited aluminium-doped zinc oxide thin films on glass substrate, using pulsed-DC magnetron sputtering, have shown high optical transmittance and low electrical resistivity with high uniformity of its spatial distribution after they were exposed to a rapid thermal annealing process at 400 °C under N{sub 2}H{sub 2} atmosphere. It is particularly interesting to note that such an annealing process of AZO thin films for only 30 s was sufficient, on one hand to improve their optical transmittance from 73% to 86%, on the other hand to both decrease their resistivity from 1.7 × 10{sup −3} Ω cm to 5.1 × 10{sup −4} Ω cm and achieve the highest uniformity spatial distribution. To understand the mechanisms behind such improvements of the optoelectronic properties, electrical, optical, structural and morphological changes as a function of annealing time have been investigated by using hall measurement, UV–visible spectrometry, X-ray diffraction and scanning electron microscope imaging, respectively.

  3. Application of fast thermal annealing to ferrites treatment; Application du recuit thermique rapide au traitement des ferrites

    Energy Technology Data Exchange (ETDEWEB)

    Legros, R.

    1995-12-31

    Annealing of magneto-optic memory disks require very fast treatment not to damage glass substrate. This article relates the optimisation of process and the choice of the most suitable alloy. Thermal rise time is linear for 15 s, then a 5 s constant 1273 degree Kelvin step is applied, and then a cooling phase starting at switching off the twelve 1 kw lamps. The most suitable alloy is the one containing manganese additions. (D.L.) 18 refs.

  4. Development of loop-mediated isothermal amplification (LAMP) assay for the rapid detection of Penicillium nordicum in dry-cured meat products.

    Science.gov (United States)

    Ferrara, M; Perrone, G; Gallo, A; Epifani, F; Visconti, A; Susca, A

    2015-06-02

    The need of powerful diagnostic tools for rapid, simple, and cost-effective detection of food-borne fungi has become very important in the area of food safety. Currently, several isothermal nucleic acid amplification methods have been developed as an alternative to PCR-based analyses. Loop-mediated isothermal amplification (LAMP) is one of these innovative methods; it requires neither gel electrophoresis to separate and visualize the products nor expensive laboratory equipment and it has been applied already for detection of pathogenic organisms. In the current study, we developed a LAMP assay for the specific detection of Penicillium nordicum, the major causative agent of ochratoxin A contamination in protein-rich food, especially dry-cured meat products. The assay was based on targeting otapksPN gene, a key gene in the biosynthesis of ochratoxin A (OTA) in P. nordicum. Amplification of DNA during the reaction was detected directly in-tube by color transition of hydroxynaphthol blue from violet to sky blue, visible to the naked eye, avoiding further post amplification analyses. Only DNAs isolated from several P. nordicum strains led to positive results and no amplification was observed from non-target OTA and non OTA-producing strains. The assay was able to detect down to 100 fg of purified targeted genomic DNA or 10(2) conidia/reaction within 60 min. The LAMP assay for detection and identification of P. nordicum was combined with a rapid DNA extraction method set up on serially diluted conidia, providing an alternative rapid, specific and sensitive DNA-based method suitable for application directly "on-site", notably in key steps of dry-cured meat production. Copyright © 2015 Elsevier B.V. All rights reserved.

  5. Rapid detection of aflatoxin producing fungi in food by real-time quantitative loop-mediated isothermal amplification.

    Science.gov (United States)

    Luo, Jie; Vogel, Rudi F; Niessen, Ludwig

    2014-12-01

    Aflatoxins represent a serious risk for human and animal health. They are mainly produced by Aspergillus flavus and Aspergillus parasiticus but also by Aspergillus nomius. Three species specific turbidimeter based real-time LAMP (loop-mediated isothermal amplification) assays were developed to quantify the three species individually in conidial solutions and to define contamination levels in samples of shelled Brazil nuts, maize, and peanuts. Standard curves relating spore numbers to time to threshold (Tt) values were set up for each of the species. Assays had detection limits of 10, 100 and 100 conidia per reaction of A. flavus, A. parasiticus, and A. nomius, respectively. Analysis of contaminated sample materials revealed that the A. nomius specific real-time LAMP assay detected a minimum of 10 conidia/g in Brazil nuts while assays specific for A. flavus and A. parasiticus had detection limits of 10(2) conidia/g and 10(5) conidia/g, respectively in peanut samples as well as 10(4) conidia/g and 10(4) conidia/g, respectively in samples of maize. The real-time LAMP assays developed here appear to be promising tools for the prediction of potential aflatoxigenic risk at an early stage and in all critical control points of the food and feed production chain. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Development of a loop-mediated isothermal amplification method for rapid mass-screening of sand flies for Leishmania infection.

    Science.gov (United States)

    Nzelu, Chukwunonso O; Gomez, Eduardo A; Cáceres, Abraham G; Sakurai, Tatsuya; Martini-Robles, Luiggi; Uezato, Hiroshi; Mimori, Tatsuyuki; Katakura, Ken; Hashiguchi, Yoshihisa; Kato, Hirotomo

    2014-04-01

    Entomological monitoring of Leishmania infection in leishmaniasis endemic areas offers epidemiologic advantages for predicting the risk and expansion of the disease, as well as evaluation of the effectiveness of control programs. In this study, we developed a highly sensitive loop-mediated isothermal amplification (LAMP) method for the mass screening of sand flies for Leishmania infection based on the 18S rRNA gene. The LAMP technique could detect 0.01 parasites, which was more sensitive than classical PCR. The method was robust and could amplify the target DNA within 1h from a crude sand fly template without DNA purification. Amplicon detection could be accomplished by the newly developed colorimetric malachite green (MG)--mediated naked eye visualization. Pre-addition of MG to the LAMP reaction solution did not inhibit amplification efficiency. The field applicability of the colorimetric MG-based LAMP assay was demonstrated with 397 field-caught samples from the endemic areas of Ecuador and eight positive sand flies were detected. The robustness, superior sensitivity, and ability to produce better visual discriminatory reaction products than existing LAMP fluorescence and turbidity assays indicated the field potential usefulness of this new method for surveillance and epidemiological studies of leishmaniasis in developing countries. Copyright © 2013 Elsevier B.V. All rights reserved.

  7. Loop-mediated isothermal amplification (LAMP) assay for the rapid detection of the sexually-transmitted parasite, Trichomonas vaginalis.

    Science.gov (United States)

    Adao, Davin Edric V; Rivera, Windell L

    2016-01-01

    A loop-mediated isothermal amplification (LAMP) assay was developed to detect the sexually-transmitted parasite, Trichomonas vaginalis in vaginal swabs. The presence of T. vaginalis was detected from 121 female sex workers attending a social hygiene clinic in Balibago, Angeles City, Pampanga, Philippines using culture, polymerase chain reaction (PCR), and the developed LAMP assay. The high analytical sensitivity of LAMP detected a higher prevalence of T. vaginalis (42.06%) compared to culture (8.26%) and PCR (7.44%). Additionally, this assay did not cross-react with DNAs of other trichomonads that can infect humans such as Trichomonas tenax and Pentatrichomonas hominis as well as the pathogens, Candida albicans and Staphylococcus aureus. The LAMP assay developed had a limit of detection (0.036 ng/μl) lower than that of PCR using the primers TvK3 and TvK7 (0.36 ng/μl). Prevalence of T. vaginalis in female sex workers in this area of the Philippines may be higher than previously estimated. Discordant results of PCR and LAMP may be due to different reactions to different kinds of inhibitors in the vaginal swabs.

  8. Loop-mediated isothermal amplification (LAMP) assays for rapid detection and differentiation of Nosema apis and N. ceranae in honeybees.

    Science.gov (United States)

    Ptaszyńska, Aneta A; Borsuk, Grzegorz; Woźniakowski, Grzegorz; Gnat, Sebastian; Małek, Wanda

    2014-08-01

    Nosemosis is a contagious disease of honeybees (Apis mellifera) manifested by increased winter mortality, poor spring build-up and even the total extinction of infected bee colonies. In this paper, loop-mediated isothermal amplifications (LAMP) were used for the first time to identify and differentiate N. apis and N. ceranae, the causative agents of nosemosis. LAMP assays were performed at a constant temperature of 60 °C using two sets of six species-specific primers, recognising eight distinct fragments of 16S rDNA gene and GspSSD polymerase with strand displacement activity. The optimal time for LAMP and its Nosema species sensitivity and specificity were assessed. LAMP only required 30 min for robust identification of the amplicons. Ten-fold serial dilutions of total DNA isolated from bees infected with microsporidia were used to determine the detection limit of N. apis and N. ceranae DNAs by LAMP and standard PCR assays. LAMP appeared to be 10(3) -fold more sensitive than a standard PCR in detecting N. apis and N. ceranae. LAMP methods developed by us are highly Nosema species specific and allow to identify and differentiate N. apis and N. ceranae. © 2014 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

  9. Development and evaluation of loop-mediated isothermal amplifiation for rapid detection of Nosema ceranae in honeybee

    Directory of Open Access Journals (Sweden)

    Vena Chupia

    2016-12-01

    Full Text Available Objective: To develop loop-mediated isothermal amplification (LAMP to detect Nosema ceranae (N. ceranae in honeybee samples. Methods: LAMP primers were designed recognizing six distinct fragments of 16s rRNA gene and LAMP reaction was determined by optimizing the concentration of reagents, such as forward inner primer and backward inner primer, deoxynucleoside triphosphate and betaine, time and temperature. Ten-fold serial dilutions of DNA were used to determine the detection limit and accuracy using both LAMP and PCR tests. Results: LAMP required 1.2 µmol/L of forward inner primer and backward inner primer primers, 0.2 µmol/L of forward outer primers and backward outer primer, 2 µmol/L of Mg2+, 0.6 mol/L of betaine, 0.6 µmol/L of deoxynucleoside triphosphate, 4.8 IU of Bst DNA polymerase and 30 ng of DNA. The optimal temperature was 63 °C and after a 40-min incubation time, a clearly ladder-like pattern of LAMP product appeared in the gel electrophoresis. LAMP appeared more sensitive than a standard PCR in detection of N. ceranae. Conclusions: LAMP gave a good results and it could be an alternative diagnostic tool instead of PCR to detect N. ceranae infection in honeybee.

  10. Application of novel loop-mediated isothermal amplification (LAMP) for rapid authentication of the herbal tea ingredient Hedyotis diffusa Willd.

    Science.gov (United States)

    Li, Ming; Wong, Yuk-Lau; Jiang, Li-Li; Wong, Ka-Lok; Wong, Yuen-Ting; Lau, Clara Bik-San; Shaw, Pang-Chui

    2013-12-01

    Hedyotis diffusa Willd. (Baihuasheshecao) is an ingredient of herbal teas commonly consumed in the Orient and tropical Asia for cancer treatment and health maintenance. In the market, this ingredient is frequently adulterated by the related species Hedyotis corymbosa (L.) Lam. The objective of this study is to develop a novel loop-mediated isothermal amplification (LAMP) technique to differentiate H. diffusa from its adulterant H. corymbosa. A set of four internal control primers (F3, FIP, BIP and B3) were designed based on six loci in the internal transcribed spacer (ITS) for LAMP of both H. diffusa and H. corymbosa. Two specific primers (S_F3 and S_FIP) were designed for specific LAMP detection of H. diffusa only. Our data showed that LAMP was successful for both H. diffusa and H. corymbosa in internal control. In contrast, only H. diffusa was detected in specific LAMP using the specific primers S_F3 and S_FIP. This study showed that LAMP was useful to differentiate H. diffusa from its adulterant H. corymbosa. This study is significant for the verification of the authenticity for better quality control of this common herbal tea ingredient. The strategy of including an internal control assures the quality of the concerned DNA region for LAMP. Copyright © 2013 Elsevier Ltd. All rights reserved.

  11. Development of Primer Sets for Loop-Mediated Isothermal Amplification that Enables Rapid and Specific Detection of Streptococcus dysgalactiae, Streptococcus uberis and Streptococcus agalactiae

    Directory of Open Access Journals (Sweden)

    Deguo Wang

    2015-05-01

    Full Text Available Streptococcus dysgalactiae, Streptococcus uberis and Streptococcus agalactiae are the three main pathogens causing bovine mastitis, with great losses to the dairy industry. Rapid and specific loop-mediated isothermal amplification methods (LAMP for identification and differentiation of these three pathogens are not available. With the 16S rRNA gene and 16S-23S rRNA intergenic spacers as targets, four sets of LAMP primers were designed for identification and differentiation of S. dysgalactiae, S. uberis and S. agalactiae. The detection limit of all four LAMP primer sets were 0.1 pg DNA template per reaction, the LAMP method with 16S rRNA gene and 16S-23S rRNA intergenic spacers as the targets can differentiate the three pathogens, which is potentially useful in epidemiological studies.

  12. Loop-mediated isothermal amplification (LAMP) assay-A rapid detection tool for identifying red fox (Vulpes vulpes) DNA in the carcasses of harbour porpoises (Phocoena phocoena).

    Science.gov (United States)

    Heers, Teresa; van Neer, Abbo; Becker, André; Grilo, Miguel Luca; Siebert, Ursula; Abdulmawjood, Amir

    2017-01-01

    Carcasses of wild animals are often visited by different scavengers. However, determining which scavenger caused certain types of bite marks is particularly difficult and knowledge thereof is lacking. Therefore, a loop-mediated isothermal amplification (LAMP) assay (target sequence cytochrome b) was developed to detect red fox DNA in carcasses of harbour porpoises. The MSwab™ method for direct testing without prior DNA isolation was validated. As a detection device, the portable real-time fluorometer Genie® II was used, which yields rapid results and can be used in field studies without huge laboratory equipment. In addition to in vitro evaluation and validation, a stranded and scavenged harbour porpoise carcass was successfully examined for red fox DNA residues. The developed LAMP method is a valuable diagnostic tool for confirming presumable red fox bite wounds in harbour porpoises without further DNA isolation steps.

  13. Rapid and ultrasensitive detection of microRNA by target-assisted isothermal exponential amplification coupled with poly (thymine)-templated fluorescent copper nanoparticles

    Science.gov (United States)

    Park, Kwan Woo; Batule, Bhagwan S.; Kang, Kyoung Suk; Park, Ki Soo; Park, Hyun Gyu

    2016-10-01

    We devised a novel method for rapid and ultrasensitive detection of target microRNA (miRNA) by employing target-assisted isothermal exponential amplification (TAIEA) combined with poly (thymine)-templated fluorescent copper nanoparticles (CuNPs) as signaling probes. The target miRNA hybridizes to the unimolecular template DNA and works as a primer for the extension reaction to form double-stranded product, which consequently generates two nicking endonuclease recognition sites. By simultaneous nicking and displacement reactions, exponential amplification generates many poly (thymine) strands as final products, which are employed for the synthesis of fluorescent CuNPs. Based on the fluorescent signal from CuNPs, target miRNA is detected as low as 0.27 fM around 1 h of total analysis time. The diagnostic capability of this system has been successfully demonstrated by reliably detecting target miRNA from different cell lysates, showing its great potential towards real clinical applications.

  14. Development of Primer Sets for Loop-Mediated Isothermal Amplification that Enables Rapid and Specific Detection of Streptococcus dysgalactiae, Streptococcus uberis and Streptococcus agalactiae.

    Science.gov (United States)

    Wang, Deguo; Liu, Yanhong

    2015-05-26

    Streptococcus dysgalactiae, Streptococcus uberis and Streptococcus agalactiae are the three main pathogens causing bovine mastitis, with great losses to the dairy industry. Rapid and specific loop-mediated isothermal amplification methods (LAMP) for identification and differentiation of these three pathogens are not available. With the 16S rRNA gene and 16S-23S rRNA intergenic spacers as targets, four sets of LAMP primers were designed for identification and differentiation of S. dysgalactiae, S. uberis and S. agalactiae. The detection limit of all four LAMP primer sets were 0.1 pg DNA template per reaction, the LAMP method with 16S rRNA gene and 16S-23S rRNA intergenic spacers as the targets can differentiate the three pathogens, which is potentially useful in epidemiological studies.

  15. Development of a loop-mediated isothermal amplification assay for rapid detection of Nocardia salmonicida, the causative agent of nocardiosis in fish.

    Science.gov (United States)

    Xia, Liqun; Zhang, Honglian; Lu, Yishan; Cai, Jia; Wang, Bei; Jian, Jichang

    2015-03-01

    Nocardia salmonicida is one of the main pathogens of fish nocardiosis. The purpose of this study was to build a loop-mediated isothermal amplification (LAMP) method for the rapid and sensitive detection of N. salmonicida. A set of four primers were designed from the 16S-23S rRNA intergenic spacer region of N. salmonicida, and conditions for LAMP were optimized as incubating all the reagents for 60 min at 64°C. LAMP products were judged with agar gel electrophoresis as well as with the naked eye after the addition of SYBR Green I. Results showed the sensitivity of the LAMP assay was 1.68 × 10(3) CFU/ml (16.8 CFU per reaction) and 10-fold higher than that of PCR. The LAMP method was also effectively applied to detect N. salmonicida in diseased fish samples, and it may potentially facilitate the surveillance and early diagnosis of fish nocardiosis.

  16. Uracil-DNA glycosylase-treated reverse transcription loop-mediated isothermal amplification for rapid detection of avian influenza virus preventing carry-over contamination.

    Science.gov (United States)

    Kim, Eun-Mi; Jeon, Hyo-Sung; Kim, Ji-Jung; Shin, Yeun-Kyung; Lee, Youn-Jeong; Yeo, Sang-Geon; Park, Choi-Kyu

    2016-09-30

    Here, we describe a uracil-DNA glycosylase (UNG)-treated reverse transcription loop-mediated isothermal amplification (uRT-LAMP) for the visual detection of all subtypes of avian influenza A virus (AIV). The uRT-LAMP assay can prevent unwanted amplification by carryover contamination of the previously amplified DNA, although the detection limit of the uRT-LAMP assay is 10-fold lower than that of the RT-LAMP without a UNG treatment. To the best of our knowledge, this is the first successful application of deoxyuridine triphosphate/UNG strategy in RT-LAMP for AIV detection, and the assay can be applied for the rapid, and reliable diagnosis of AIVs, even in contaminated samples.

  17. Development of a loop-mediated isothermal amplification (LAMP) assay for rapid and specific detection of common genetically modified organisms (GMOs).

    Science.gov (United States)

    Feng, Jiawang; Tang, Shiming; Liu, Lideng; Kuang, Xiaoshan; Wang, Xiaoyu; Hu, Songnan; You, Shuzhu

    2015-03-01

    Here, we developed a loop-mediated isothermal amplification (LAMP) assay for 11 common transgenic target DNA in GMOs. Six sets of LAMP primer candidates for each target were designed and their specificity, sensitivity, and reproductivity were evaluated. With the optimized LAMP primers, this LAMP assay was simply run within 45-60 min to detect all these targets in GMOs tested. The sensitivity, specificity, and reproductivity of the LAMP assay were further analyzed in comparison with those of Real-Time PCR. In consistent with real-time PCR, detection of 0.5% GMOs in equivalent background DNA was possible using this LAMP assay for all targets. In comparison with real-time PCR, the LAMP assay showed the same results with simple instruments. Hence, the LAMP assay developed can provide a rapid and simple approach for routine screening as well as specific events detection of many GMOs.

  18. Rapid, Sensitive, and Carryover Contamination-Free Loop-Mediated Isothermal Amplification-Coupled Visual Detection Method for 'Candidatus Liberibacter asiaticus'.

    Science.gov (United States)

    Qian, Wenjuan; Meng, Youqing; Lu, Ying; Wu, Cui; Wang, Rui; Wang, Liu; Qian, Cheng; Ye, Zunzhong; Wu, Jian; Ying, Yibin

    2017-09-27

    Huanglongbing is a devastating citrus disease, and 'Candidatus Liberibacter asiaticus' (Las) is the most prevalent huanglongbing-associated bacterium. Its field detection remains challenging. In this work, a visual, rapid, sensitive, and carryover contamination-free method was developed for field detection of Las. Leaf samples were treated with 500 μL of 0.5 M sodium hydroxide solution for 3 min, and 50-fold dilutions were directly amplified by loop-mediated isothermal amplification. Then, a novel SYTO-9-based visual detection method was used to evaluate amplification results without uncapping operation. Negative samples remained colorless, while positive samples generated obvious green fluorescence, which could be easily distinguished by the naked eye with a mini-fluorescent-emission cartridge developed originally. The proposed detection method could be accomplished within 40 min and is about 100 times more sensitive than conventional TaqMan polymerase chain reaction. The reliability of this method was also verified by analyzing practical samples.

  19. The effect of the rapid thermal annealing on the interdiffusion and the reaction at the interface of the binary system Cr/Si

    Energy Technology Data Exchange (ETDEWEB)

    Merabet, A. [Laboratoire Physique et Mecanique des Materiaux Metalliques, Departement d' O.M.P., Faculte des Sciences de l' Ingenieur, Universite de Setif, Setif 19000 (Algeria)]. E-mail: merabet_abdelali@yahoo.fr

    2004-12-15

    In order to understand the growth mechanism of the silicides and the effect of the dopant on the electrical activity, a thin layer of chromium (100 nm) is deposited on the single crystal silicon (1 0 0) substrate implanted (10{sup 15} As{sup +} atoms/cm{sup 2}, 100 keV) and non implanted. Afterwards, we performed a rapid thermal annealing in the interval of temperature (450-600 deg. C) for a fixed duration of 45 s. The samples are analyzed by X ray-diffraction (XRD) and Rutherford backscattering spectrometry (RBS). The electrical activity has been investigated by the method of the four-point probes. The analysis of the samples by XRD and RBS showed that the rapid thermal annealing (RTA) leads to a reaction at the interface Cr/Si inducing the formation and the growth of the unique silicide CrSi{sub 2}. It is also established that the kinetics growth of CrSi{sub 2} presents a linear evolution with temperature. This fact shows that the growth is governed by a chemical reaction of the interface. Sheet resistance measurements have been performed to study the electrical behavior for these structures. It is worth to point out that the presence of the implanted arsenic in the single crystal silicon increased the resistance in a significant manner.

  20. Ion-beam mixed ultra-thin cobalt suicide (CoSi2) films by cobalt sputtering and rapid thermal annealing

    Science.gov (United States)

    Kal, S.; Kasko, I.; Ryssel, H.

    1995-10-01

    The influence of ion-beam mixing on ultra-thin cobalt silicide (CoSi2) formation was investigated by characterizing the ion-beam mixed and unmixed CoSi2 films. A Ge+ ion-implantation through the Co film prior to silicidation causes an interface mixing of the cobalt film with the silicon substrate and results in improved silicide-to-silicon interface roughness. Rapid thermal annealing was used to form Ge+ ion mixed and unmixed thin CoSi2 layer from 10 nm sputter deposited Co film. The silicide films were characterized by secondary neutral mass spectroscopy, x-ray diffraction, tunneling electron microscopy (TEM), Rutherford backscattering, and sheet resistance measurements. The experi-mental results indicate that the final rapid thermal annealing temperature should not exceed 800°C for thin (films reveals that Ge+ ion mixing (45 keV, 1 × 1015 cm-2) produces homogeneous silicide with smooth silicide-to-silicon interface.

  1. Development and application of loop-mediated isothermal amplification assays for rapid visual detection of cry2Ab and cry3A genes in genetically-modified crops.

    Science.gov (United States)

    Li, Feiwu; Yan, Wei; Long, Likun; Qi, Xing; Li, Congcong; Zhang, Shihong

    2014-08-27

    The cry2Ab and cry3A genes are two of the most important insect-resistant exogenous genes and had been widely used in genetically-modified crops. To develop more effective alternatives for the quick identification of genetically-modified organisms (GMOs) containing these genes, a rapid and visual loop-mediated isothermal amplification (LAMP) method to detect the cry2Ab and cry3A genes is described in this study. The LAMP assay can be finished within 60 min at an isothermal condition of 63 °C. The derived LAMP products can be obtained by a real-time turbidimeter via monitoring the white turbidity or directly observed by the naked eye through adding SYBR Green I dye. The specificity of the LAMP assay was determined by analyzing thirteen insect-resistant genetically-modified (GM) crop events with different Bt genes. Furthermore, the sensitivity of the LAMP assay was evaluated by diluting the template genomic DNA. Results showed that the limit of detection of the established LAMP assays was approximately five copies of haploid genomic DNA, about five-fold greater than that of conventional PCR assays. All of the results indicated that this established rapid and visual LAMP assay was quick, accurate and cost effective, with high specificity and sensitivity. In addition, this method does not need specific expensive instruments or facilities, which can provide a simpler and quicker approach to detecting the cry2Ab and cry3A genes in GM crops, especially for on-site, large-scale test purposes in the field.

  2. Development and Application of Loop-Mediated Isothermal Amplification Assays for Rapid Visual Detection of cry2Ab and cry3A Genes in Genetically-Modified Crops

    Directory of Open Access Journals (Sweden)

    Feiwu Li

    2014-08-01

    Full Text Available The cry2Ab and cry3A genes are two of the most important insect-resistant exogenous genes and had been widely used in genetically-modified crops. To develop more effective alternatives for the quick identification of genetically-modified organisms (GMOs containing these genes, a rapid and visual loop-mediated isothermal amplification (LAMP method to detect the cry2Ab and cry3A genes is described in this study. The LAMP assay can be finished within 60 min at an isothermal condition of 63 °C. The derived LAMP products can be obtained by a real-time turbidimeter via monitoring the white turbidity or directly observed by the naked eye through adding SYBR Green I dye. The specificity of the LAMP assay was determined by analyzing thirteen insect-resistant genetically-modified (GM crop events with different Bt genes. Furthermore, the sensitivity of the LAMP assay was evaluated by diluting the template genomic DNA. Results showed that the limit of detection of the established LAMP assays was approximately five copies of haploid genomic DNA, about five-fold greater than that of conventional PCR assays. All of the results indicated that this established rapid and visual LAMP assay was quick, accurate and cost effective, with high specificity and sensitivity. In addition, this method does not need specific expensive instruments or facilities, which can provide a simpler and quicker approach to detecting the cry2Ab and cry3A genes in GM crops, especially for on-site, large-scale test purposes in the field.

  3. Clinical evaluation of a loop-mediated isothermal amplification (LAMP assay for rapid detection of Neisseria meningitidis in cerebrospinal fluid.

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    DoKyung Lee

    Full Text Available Neisseria meningitidis (Nm is a leading causative agent of bacterial meningitis in humans. Traditionally, meningococcal meningitis has been diagnosed by bacterial culture. However, isolation of bacteria from patients' cerebrospinal fluid (CSF is time consuming and sometimes yields negative results. Recently, polymerase chain reaction (PCR-based diagnostic methods of detecting Nm have been considered the gold standard because of their superior sensitivity and specificity compared with culture. In this study, we developed a loop-mediated isothermal amplification (LAMP method and evaluated its ability to detect Nm in cerebrospinal fluid (CSF.We developed a meningococcal LAMP assay (Nm LAMP that targets the ctrA gene. The primer specificity was validated using 16 strains of N. meningitidis (serogroup A, B, C, D, 29-E, W-135, X, Y, and Z and 19 non-N. meningitidis species. Within 60 min, the Nm LAMP detected down to ten copies per reaction with sensitivity 1000-fold more than that of conventional PCR. The LAMP assays were evaluated using a set of 1574 randomly selected CSF specimens from children with suspected meningitis collected between 1998 and 2002 in Vietnam, China, and Korea. The LAMP method was shown to be more sensitive than PCR methods for CSF samples (31 CSF samples were positive by LAMP vs. 25 by PCR. The detection rate of the LAMP method was substantially higher than that of the PCR method. In a comparative analysis of the PCR and LAMP assays, the clinical sensitivity, specificity, positive predictive value, and negative predictive value of the LAMP assay were 100%, 99.6%, 80.6%, and 100%, respectively.Compared to PCR, LAMP detected Nm with higher analytical and clinical sensitivity. This sensitive and specific LAMP method offers significant advantages for screening patients on a population basis and for diagnosis in clinical settings.

  4. Rapid colorimetric detection of Zika virus from serum and urine specimens by reverse transcription loop-mediated isothermal amplification (RT-LAMP).

    Science.gov (United States)

    Calvert, Amanda E; Biggerstaff, Brad J; Tanner, Nathan A; Lauterbach, Molly; Lanciotti, Robert S

    2017-01-01

    Zika virus (ZIKV) has emerged as a major global public health concern in the last two years due to its link as a causative agent of human birth defects. Its rapid expansion into the Western Hemisphere as well as the ability to be transmitted from mother to fetus, through sexual transmission and possibly through blood transfusions has increased the need for a rapid and expansive public health response to this unprecedented epidemic. A non-invasive and rapid ZIKV diagnostic screening assay that can be performed in a clinical setting throughout pregnancy is vital for prenatal care of women living in areas of the world where exposure to the virus is possible. To meet this need we have developed a sensitive and specific reverse transcriptase loop-mediated isothermal amplification (RT-LAMP) assay to detect ZIKV RNA in urine and serum with a simple visual detection. RT-LAMP results were shown to have a limit of detection 10-fold higher than qRT-PCR. As little as 1.2 RNA copies/μl was detected by RT-LAMP from a panel of 178 diagnostic specimens. The assay was shown to be highly specific for ZIKV RNA when tested with diagnostic specimens positive for dengue virus (DENV) and chikungunya virus (CHIKV). The assay described here illustrates the potential for a fast, reliable, sensitive and specific assay for the detection of ZIKV from urine or serum that can be performed in a clinical or field setting with minimal equipment and technological expertise.

  5. Development of a real-time fluorescence loop-mediated isothermal amplification assay for rapid and quantitative detection of Fusarium oxysporum f. sp. niveum in soil.

    Science.gov (United States)

    Peng, Jun; Zhan, Yuanfeng; Zeng, Fanyun; Long, Haibo; Pei, Yuelin; Guo, Jianrong

    2013-12-01

    Fusarium wilt caused by Fusarium oxysporum f. sp. niveum (Fon) is one of the major limiting factors for watermelon production worldwide. Rapid and accurate detection of the causal pathogen is the cornerstone of integrated disease management. In this paper, a real-time fluorescence loop-mediated isothermal amplification (RealAmp) assay was developed for the rapid and quantitative detection of Fon in soil. Positive products were amplified only from Fon isolates and not from any other species or formae speciales of F. oxysporum tested, showing a high specificity of the primer sets. The detection limit of the RealAmp assay was 1.2 pg μL(-1) genomic DNA or 10(3) spores g(-1) of artificially inoculated soil, whereas real-time PCR could detect as low as 12 fg μL(-1) or 10(2) spores g(-1). The RealAmp assay was further applied to detect eight artificially inoculated and 85 field soil samples. No significant differences were found between the results tested by the RealAmp and real-time PCR assays. The RealAmp assay is a simple, rapid and effective technique for the quantitative detection and monitoring of Fon in soil under natural conditions. © 2013 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

  6. A rapid molecular diagnosis of cutaneous leishmaniasis by colorimetric malachite green-loop-mediated isothermal amplification (LAMP) combined with an FTA card as a direct sampling tool.

    Science.gov (United States)

    Nzelu, Chukwunonso O; Cáceres, Abraham G; Guerrero-Quincho, Silvia; Tineo-Villafuerte, Edwin; Rodriquez-Delfin, Luis; Mimori, Tatsuyuki; Uezato, Hiroshi; Katakura, Ken; Gomez, Eduardo A; Guevara, Angel G; Hashiguchi, Yoshihisa; Kato, Hirotomo

    2016-01-01

    Leishmaniasis remains one of the world's most neglected diseases, and early detection of the infectious agent, especially in developing countries, will require a simple and rapid test. In this study, we established a quick, one-step, single-tube, highly sensitive loop-mediated isothermal amplification (LAMP) assay for rapid detection of Leishmania DNA from tissue materials spotted on an FTA card. An FTA-LAMP with pre-added malachite green was performed at 64°C for 60min using a heating block and/or water bath and DNA amplification was detected immediately after incubation. The LAMP assay had high detection sensitivity down to a level of 0.01 parasites per μl. The field- and clinic-applicability of the colorimetric FTA-LAMP assay was demonstrated with 122 clinical samples collected from patients suspected of having cutaneous leishmaniasis in Peru, from which 71 positives were detected. The LAMP assay in combination with an FTA card described here is rapid and sensitive, as well as simple to perform, and has great potential usefulness for diagnosis and surveillance of leishmaniasis in endemic areas. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. Field Evaluation of Malaria Microscopy, Rapid Malaria Tests and Loop-Mediated Isothermal Amplification in a Rural Hospital in South Western Ethiopia.

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    Juan Cuadros

    Full Text Available In up to one third of the hospitals in some rural areas of Africa, laboratory services in malaria diagnosis are limited to microscopy by thin film, as no capability to perform thick film exists (gold standard in terms of sensitivity for malaria diagnosis. A new rapid molecular malaria diagnostic test called Loop-mediated isothermal DNA amplification (LAMP has been recently validated in clinical trials showing exceptional sensitivity and specificity features. It could be a reliable diagnostic tool to be implemented without special equipment or training.The objective of this proof of concept study was to confirm the feasibility of using LAMP technique for diagnosis of malaria in a rural Ethiopian hospital with limited resources.This study was carried out in Gambo General Hospital, West Arsi Province (Ethiopia, from November 1st to December 31st 2013. A total of 162 patients with a non-focal febrile syndrome were investigated. The diagnostic capability (sensitivity, specificity, positive predictive and negative predictive values of rapid malaria tests and microscopy by thin film was evaluated in comparison with LAMP. Eleven (6.79% out of the 162 patients with fever and suspected malaria, tested positive for LAMP, 3 (1.85% for rapid malaria tests and none of the eleven cases was detected by thin film microscopy.LAMP can be performed in basic rural laboratories without the need for specialized infrastructure and it may set a reliable tool for malaria control to detect a low level parasitemia.

  8. Development of a simple and rapid reverse transcription-loop mediated isothermal amplification (RT-LAMP) assay for sensitive detection of Citrus tristeza virus.

    Science.gov (United States)

    Warghane, Ashish; Misra, Pragati; Bhose, Sumit; Biswas, Kajal Kumar; Sharma, Ashwani Kumar; Reddy, M Krishna; Ghosh, Dilip Kumar

    2017-12-01

    Tristeza is a devastating disease of citrus and reported to be present in almost all countries where it is cultivated as a commercial crop. The etiological agent of this disease is Citrus tristeza virus (CTV), a member of the genus Closterovirus with in the family Closteroviridae. The pathogen is restricted to the phloem tissue of the infected citrus plant and has a monopartite ss (+) RNA genome of ∼20kb size. Till date, there is no effective control measure available for this virus. Management of tristeza depends on destruction of CTV infected field plants, production of virus-free planting material for new orchard establishment and controlling viruliferous aphid vectors responsible for field spread of the pathogen. Availability of rapid diagnostic assay is essential for rapid and efficient detection of the pathogen. In the present investigation, RT-LAMP (reverse transcription-loop mediated isothermal amplification), a highly sensitive, robust and low cost assay has been developed for rapid detection of CTV in infected citrus plant samples. Based on conserved nucleotide sequences available in GenBank and specific to p25 gene (major coat protein gene) of predominant CTV isolates of India, four primer sets (CTV-F3, CTV-B3, CTV-FIP and CTV-BIP) ware designed and custom synthesized. The amplified LAMP products obtained after maintaining isothermal condition of 65°C for 60min duration could be visible easily with necked eyes in presence of SYBR Green I (100X). Subsequently, LAMP products were verified by electrophoresis run in 1.5% agarose gel. The RT-LAMP results obtained with known CTV isolates maintained in screen house of CCRI, Nagpur were validated using field samples and thereafter it was further confirmed by conventional RT-PCR (reveres transcription-polymerase chain reaction) assay. The sensitivity of CTV-RT-LAMP protocol standardized in the present study was 100 times more than conventional one step RT-PCR assay. It also has maximum detection limit up to 0

  9. Development of Loop-Mediated Isothermal Amplification (LAMP) assay for rapid detection of Fusarium oxysporum f. sp. ciceris - wilt pathogen of chickpea.

    Science.gov (United States)

    Ghosh, Raju; Nagavardhini, Avuthu; Sengupta, Anindita; Sharma, Mamta

    2015-02-11

    Fusarium oxysporum f. sp. ciceris (Foc), the causal agent of Fusarium wilt is a devastating pathogen of chickpea. In chickpea, various soil borne pathogens produce (s) similar symptoms, therefore cannot be distinguished easily at field level. There is real need for a rapid, inexpensive, and easy to operate and maintain genotyping tool to facilitate accurate disease diagnosis and surveillance for better management of Fusarium wilt outbreaks. In this study, we developed a loop-mediated isothermal amplification (LAMP) assay targeting the elongation factor 1 alpha gene sequence for visual detection of Foc. The LAMP reaction was optimal at 63°C for 60 min. When hydroxynaphthol blue (HNB) was added before amplification, samples with Foc DNA developed a characteristic sky blue colour but those without DNA or with the DNA of six other plant pathogenic fungi did not. Results obtained with LAMP and HNB were confirmed when LAMP products were subjected to gel electrophoresis. The detection limit of this LAMP assay for Foc was 10 fg of genomic DNA per reaction, while that of conventional PCR was 100 pg. In conclusion, it was found that a LAMP assay combined with HNB is simple, rapid, sensitive, and specific. The LAMP assay does not require specialized equipment, hence can be used in the field for the rapid detection of Foc. This is the first report of the use of LAMP assay for the detection of Foc. The presented LAMP method provides a specific, sensitive and rapid diagnostic tool for the distinction of Foc, with the potential to be standardized as a detection method for Foc in endemic areas and will be very useful for monitoring the disease complex in the field further suggesting the management strategies.

  10. Influence of Annealing Temperature on the Magnetic Properties of Rapidly Quenched (Nd,Pr2-(Fe,Co,Ga,Ti,C14B/α-Fe Nanocomposite Ribbons

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    Rahim Sabbaghizadeh

    2013-01-01

    Full Text Available The effects of different heat treatment temperatures on the structure and magnetic properties of Nd-Fe-B nanocomposite permanent magnetic alloys with nominal composition of Nd9.4Pr0.6Fe74.5Co6B6Ga0.5Ti1.5C1.5 have been investigated. The most practical method to produce nanostructured metallic materials is rapid solidification. Melt spinning with constant wheel speed of V=40 m/s was employed to produce ribbons. As-spun ribbons were examined by using differential scanning calorimetry (DSC and X-ray diffractometer (XRD with Cu-kα radiation. The ribbons were annealed at different temperatures in order to extract the best magnetic properties. The XRD and electron microscopy technique results confirm that grains are in the size of less than 50 nm. In addition, optimum magnetic properties were obtained at 700°C annealed temperature.

  11. Development of a Loop-Mediated Isothermal Amplification Assay for Rapid and Specific Identification of ACT Producing Alternaria alternata, the Agent of Brown Spot Disease in Tangerine.

    Science.gov (United States)

    Moghimi, Hamid; Moradi, Amir; Hamedi, Javad; Basiri, Mina

    2016-03-01

    Rapid, accurate, and easy identification of pathogenic agents has always been important in medicine, veterinary, and agriculture. The brown spot infection is among the most common diseases in tangerine caused by Alternaria alternata. Due to the existence of seven various pathotypes of A. alternata species, it is challenging and time consuming to detect a pathotype responsible for citrus brown spot. In this study, we were seeking a rapid and specific approach to identify the tangerine pathotype within the A. alternata-pathogenic species, using the loop-mediated isothermal amplification (LAMP) method and actts2 gene as a marker molecule. Nine pathogenic samples were obtained from the region of Ramsar, Iran, and certified as A. alternata-pathogenic isolates. Specific primers were designed for regions coding for Alternaria citri toxin (ACT), and the PCR and LAMP reactions were performed. Our data showed that the primers designed for the tangerine pathotype of A. alternata were specific, and in both reactions, positive results were only observed in desired pathotypes. In the other pathotypes of this species as well as other standard fungal samples as negative controls, no positive result was observed. Therefore, our results suggest the possibility to detect the tangerine-specific A. alternata pathotype from other related species with a high accuracy and in early stages of the disease.

  12. Development and Evaluation of Loop-Mediated Isothermal Amplification Assay for Rapid Detection of Tylenchulus semipenetrans Using DNA Extracted from Soil

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    Zhi-Qiang Song

    2017-04-01

    Full Text Available Tylenchulus semipenetrans is an important and widespread plant-parasitic nematode of citrus worldwide and can cause citrus slow decline disease leading to significant reduction in tree growth and yield. Rapid and accurate detection of T. semipenetrans in soil is important for the disease forecasting and management. In this study, a loop-mediated isothermal amplification (LAMP assay was developed to detect T. semipenetrans using DNA extracted from soil. A set of five primers was designed from the internal transcribed spacer region (ITS1 of rDNA, and was highly specific to T. semipenetrans. The LAMP reaction was performed at 63°C for 60 min. The LAMP product was visualized directly in one reaction tube by adding SYBR Green I. The detection limit of the LAMP assay was 10−2 J2/0.5 g of soil, which was 10 times more sensitive than conventional PCR (10−1 J2/0.5 g of soil. Examination of 24 field soil samples revealed that the LAMP assay was applicable to a range of soils infested naturally with T. semipenetrans, and the total assay time was less than 2.5 h. These results indicated that the developed LAMP assay is a simple, rapid, sensitive, specific and accurate technique for detection of T. semipenetrans in field soil, and contributes to the effective management of citrus slow decline disease.

  13. Rapid diagnostic detection of plum pox virus in Prunus plants by isothermal AmplifyRP(®) using reverse transcription-recombinase polymerase amplification.

    Science.gov (United States)

    Zhang, Shulu; Ravelonandro, Michel; Russell, Paul; McOwen, Nathan; Briard, Pascal; Bohannon, Seven; Vrient, Albert

    2014-10-01

    Plum pox virus (PPV) causes the most destructive viral disease known as plum pox or Sharka disease in stone fruit trees. As an important regulated pathogen, detection of PPV is thus of critical importance to quarantine and eradication of the spreading disease. In this study, the innovative development of two AmplifyRP(®) tests is reported for a rapid isothermal detection of PPV using reverse transcription-recombinase polymerase amplification. In an AmplifyRP(®) test, all specific recombination and amplification reactions occur at a constant temperature without thermal cycling and the test results are either recorded in real-time with a portable fluorescence reader or displayed using a lateral flow strip contained inside an amplicon detection chamber. The major improvement of this assay is that the entire test from sample preparation to result can be completed in as little as 20min and can be performed easily both in laboratories and in the field. The results from this study demonstrated the ability of the AmplifyRP(®) technique to detect all nine PPV strains (An, C, CR, D, EA, M, Rec, T, or W). Among the economic benefits to pathogen surveys is the higher sensitivity of the AmplifyRP(®) to detect PPV when compared to the conventional ELISA and ImmunoStrip(®) assays. This is the first report describing the use of such an innovative technique to detect rapidly plant viruses affecting perennial crops. Copyright © 2014 Elsevier B.V. All rights reserved.

  14. Rapid and simple detection of Japanese encephalitis virus by reverse transcription loop-mediated isothermal amplification combined with a lateral flow dipstick.

    Science.gov (United States)

    Deng, Jieru; Pei, Jingjing; Gou, Hongchao; Ye, Zuodong; Liu, Cuicui; Chen, Jinding

    2015-03-01

    Japanese encephalitis virus (JEV) is a major cause of viral encephalitis in geographical areas, such as Asia and Western Pacific, where it is a threat to human and animal health. To control this disease, it is necessary to develop a rapid, simple, accurate method for diagnosis. In this study, a method based on reverse transcription loop-mediated isothermal amplification (RT-LAMP) coupled with a lateral flow dipstick (LFD) has been developed to detect JEV (JEV RT-LAMP-LFD). The entire assay can be completed within 70 min, and in this study, no false positive results were observed when other pathogens were tested, indicating that the assay is a highly specific method for the detection of JEV. Additionally, the sensitivity of the RT-LAMP-LFD assay for SA14-14-2 strain was 50 pg of RNA, which was similar to that of RT-PCR and RT-LAMP combined with gel electrophoresis, and was 10-fold more sensitive than RT-LAMP combined with calcein. The limit of detection for this assay was 5 pg of RNA. In addition, no false positive results were obtained with 14 serum samples. Our results indicate that this RT-LAMP-LFD assay will be of great value for JEV infection testing due to its rapid and highly specific and sensitive properties. Copyright © 2014 Elsevier B.V. All rights reserved.

  15. Pulsed Laser Annealing of Carbon

    Science.gov (United States)

    Abrahamson, Joseph P.

    This dissertation investigates laser heating of carbon materials. The carbon industry has been annealing carbon via traditional furnace heating since at least 1800, when Sir Humphry Davy produced an electric arc with carbon electrodes made from carbonized wood. Much knowledge has been accumulated about carbon since then and carbon materials have become instrumental both scientifically and technologically. However, to this day the kinetics of annealing are not known due to the slow heating and cooling rates of furnaces. Additionally, consensus has yet to be reached on the cause of nongraphitizability. Annealing trajectories with respect to time at temperature are observed from a commercial carbon black (R250), model graphitizable carbon (anthracene coke) and a model nongraphitizable carbon (sucrose char) via rapid laser heating. Materials were heated with 1064 nm and 10.6 im laser radiation from a Q-switched Nd:YAG laser and a continuous wave CO2 laser, respectively. A pulse generator was used reduce the CO2 laser pulse width and provide high temporal control. Time-temperature-histories with nanosecond temporal resolution and temperature reproducibility within tens of degrees Celsius were determined by spectrally resolving the laser induced incandescence signal and applying multiwavelength pyrometry. The Nd:YAG laser fluences include: 25, 50, 100, 200, 300, and 550 mJ/cm2. The maximum observed temperature ranged from 2,400 °C to the C2 sublimation temperature of 4,180 °C. The CO2 laser was used to collect a series of isothermal (1,200 and 2,600 °C) heat treatments versus time (100 milliseconds to 30 seconds). Laser heated samples are compared to furnace annealing at 1,200 and 2,600 °C for 1 hour. The material transformation trajectory of Nd:YAG laser heated carbon is different than traditional furnace heating. The traditional furnace annealing pathway is followed for CO2 laser heating as based upon equivalent end structures. The nanostructure of sucrose char

  16. Field-Deployable Reverse Transcription-Insulated Isothermal PCR (RT-iiPCR) Assay for Rapid and Sensitive Detection of Foot-and-Mouth Disease Virus.

    Science.gov (United States)

    Ambagala, A; Fisher, M; Goolia, M; Nfon, C; Furukawa-Stoffer, T; Ortega Polo, R; Lung, O

    2017-10-01

    Foot-and-mouth disease (FMD) is a highly contagious viral disease of cloven-hoofed animals, which can decimate the livestock industry and economy of countries previously free of this disease. Rapid detection of foot-and-mouth disease virus (FMDV) is critical to containing an FMD outbreak. Availability of a rapid, highly sensitive and specific, yet simple and field-deployable assay would support local decision-making during an FMDV outbreak. Here we report validation of a novel reverse transcription-insulated isothermal PCR (RT-iiPCR) assay that can be performed on a commercially available, compact and portable POCKIT™ analyser that automatically analyses data and displays '+' or '-' results. The FMDV RT-iiPCR assay targets the 3D region of the FMDV genome and was capable of detecting 9 copies of in vitro-transcribed RNA standard with 95% confidence. It accurately identified 63 FMDV strains belonging to all seven serotypes and showed no cross-reactivity with viruses causing similar clinical diseases in cloven-hoofed animals. The assay was able to identify FMDV RNA in multiple sample types including oral, nasal and lesion swabs, epithelial tissue suspensions, vesicular and oral fluid samples, even before the appearance of clinical signs. Clinical sensitivity of the assay was comparable or slightly higher than the laboratory-based real-time RT-PCR assay in use. The assay was able to detect FMDV RNA in vesicular fluid samples without nucleic acid extraction. For RNA extraction from more complex sample types, a commercially available taco™ mini transportable magnetic bead-based, automated extraction system was used. This assay provides a potentially useful field-deployable diagnostic tool for rapid detection of FMDV in an outbreak in FMD-free countries or for routine diagnostics in endemic countries with less structured laboratory systems. © 2016 Her Majesty the Queen in Right of Canada.

  17. Rapid colorimetric detection of Zika virus from serum and urine specimens by reverse transcription loop-mediated isothermal amplification (RT-LAMP.

    Directory of Open Access Journals (Sweden)

    Amanda E Calvert

    Full Text Available Zika virus (ZIKV has emerged as a major global public health concern in the last two years due to its link as a causative agent of human birth defects. Its rapid expansion into the Western Hemisphere as well as the ability to be transmitted from mother to fetus, through sexual transmission and possibly through blood transfusions has increased the need for a rapid and expansive public health response to this unprecedented epidemic. A non-invasive and rapid ZIKV diagnostic screening assay that can be performed in a clinical setting throughout pregnancy is vital for prenatal care of women living in areas of the world where exposure to the virus is possible. To meet this need we have developed a sensitive and specific reverse transcriptase loop-mediated isothermal amplification (RT-LAMP assay to detect ZIKV RNA in urine and serum with a simple visual detection. RT-LAMP results were shown to have a limit of detection 10-fold higher than qRT-PCR. As little as 1.2 RNA copies/μl was detected by RT-LAMP from a panel of 178 diagnostic specimens. The assay was shown to be highly specific for ZIKV RNA when tested with diagnostic specimens positive for dengue virus (DENV and chikungunya virus (CHIKV. The assay described here illustrates the potential for a fast, reliable, sensitive and specific assay for the detection of ZIKV from urine or serum that can be performed in a clinical or field setting with minimal equipment and technological expertise.

  18. Rapid and Sensitive Detection of Norovirus Genomes in Oysters by a Two-Step Isothermal Amplification Assay System Combining Nucleic Acid Sequence-Based Amplification and Reverse Transcription-Loop-Mediated Isothermal Amplification Assays▿

    Science.gov (United States)

    Fukuda, Shinji; Sasaki, Yukie; Seno, Masato

    2008-01-01

    We developed a two-step isothermal amplification assay system, which achieved the detection of norovirus (NoV) genomes in oysters with a sensitivity similar to that of reverse transcription-seminested PCR. The time taken for the amplification of NoV genomes from RNA extracts was shortened to about 3 h. PMID:18456857

  19. Rapid and Sensitive Detection of Norovirus Genomes in Oysters by a Two-Step Isothermal Amplification Assay System Combining Nucleic Acid Sequence-Based Amplification and Reverse Transcription-Loop-Mediated Isothermal Amplification Assays▿

    OpenAIRE

    Fukuda, Shinji; Sasaki, Yukie; Seno, Masato

    2008-01-01

    We developed a two-step isothermal amplification assay system, which achieved the detection of norovirus (NoV) genomes in oysters with a sensitivity similar to that of reverse transcription-seminested PCR. The time taken for the amplification of NoV genomes from RNA extracts was shortened to about 3 h.

  20. Rapid and sensitive detection of norovirus genomes in oysters by a two-step isothermal amplification assay system combining nucleic acid sequence-based amplification and reverse transcription-loop-mediated isothermal amplification assays.

    Science.gov (United States)

    Fukuda, Shinji; Sasaki, Yukie; Seno, Masato

    2008-06-01

    We developed a two-step isothermal amplification assay system, which achieved the detection of norovirus (NoV) genomes in oysters with a sensitivity similar to that of reverse transcription-seminested PCR. The time taken for the amplification of NoV genomes from RNA extracts was shortened to about 3 h.

  1. Sensitive and rapid detection of campylobacter species from stools of children with diarrhea in Japan by the loop-mediated isothermal amplification method.

    Science.gov (United States)

    Ushijima, Hiroshi; Nishimura, Shuichi; Thongprachum, Aksara; Shimizu-Onda, Yuko; Tran, Dinh Nguyen; Pham, Ngan Thi Kim; Takanashi, Sayaka; Dey, Shuvra Kanti; Okitsu, Shoko; Yamazaki, Wataru; Mizuguchi, Masashi; Hayakawa, Satoshi

    2014-01-01

    We detected Campylobacter spp. in 5% (20/380) of diarrheal stool samples collected at an outpatient clinic in Kyoto using a commercial loop-mediated isothermal amplification (LAMP) kit with a fluorescent detection reagent after DNA extraction. The sensitivity and specificity were 100% in comparison with those of semi-nested PCR for the differentiation of Campylobacter jejuni and Campylobacter coli. Fourteen of the 20 samples were already determined as C. jejuni by the culture method. All 20 samples were also positive for C. jejuni by the PCR method. Among the 58 cultured samples, the sensitivity of the culture method against the LAMP method was 93.3% (14/15) and the specificity was 100% (43/43). The detection rate of Campylobacter spp. from the heated supernatants by the LAMP method was lower than that from the supernatant after DNA extraction. In total, 25% (5/20) of the Campylobacter-positive samples by the LAMP method were co-infected with norovirus (3/20), rotavirus (1/20), and human parechovirus (1/20), although no other bacterial co-infection was identified by the culture method. C. jejuni was mostly detected in children aged >5 years throughout the year. Based on these results, we concluded that care should be taken while diagnosing Campylobacter infection in children. Our newly modified LAMP method is a rapid, easy, and useful method for this diagnosis.

  2. Rapid and Sensitive Detection of the Main Contaminating Fungus Penicillium restrictum in Jet Fuel using Loop-Mediated Isothermal Amplification Combined with a Lateral Flow Dipstick

    Directory of Open Access Journals (Sweden)

    Xiong Yun

    2016-06-01

    Full Text Available We report a new contaminating fungus of jet fuel, Penicillium restrictum, which accounted for nearly 17% of the total sequence identified from five jet fuel samples as determined by the application of Illumina MiSeq sequencing-by-synthesis. We also report the development and validation of a new loop-mediated isothermal amplification (LAMP assay combined with a lateral flow dipstick (LFD for the repaid detection of P. restrictum. The optimal reaction conditions and primer set for LAMP were determined using a real-time turbidimeter. The LAMP-LFD assay was 1000-fold more sensitive than traditional PCR. P. restrictum could be detected specifically using the LAMP-LFD assay, and no amplification was observed when genomic DNA from another seven fungi found in jet fuel was tested. Eleven jet fuel samples from the field were tested using the LAMP-LFD assay we developed. Seven of them were positive for the presence of P. restrictum. These results were verified by traditional microbiological detection methods. Our results indicate that the LAMP-LFD assay is a rapid, accurate and sensitive tool for the detection of P. restrictum and could represent a new template for the detection of contaminating fungi in jet fuel.

  3. Rapid and sensitive detection of Mycoplasma synoviae by an insulated isothermal polymerase chain reaction-based assay on a field-deployable device.

    Science.gov (United States)

    Kuo, Hung-Chih; Lo, Dan-Yuan; Chen, Chiou-Lin; Tsai, Yun-Long; Ping, Jia-Fong; Lee, Chien-Hsien; Lee, Pei-Yu Alison; Chang, Hsiao-Fen Grace

    2017-01-01

    Mycoplasma synoviae (MS), causing respiratory diseases, arthritis, and eggshell apex abnormalities in avian species, is an important pathogen in the poultry industry. Implementation of a biosecurity plan is important in MS infection management. Working on a field-deployable POCKIT™ device, an insulated isothermal polymerase chain reaction (iiPCR) assay has a potential for timely MS detection on the farm. The MS iiPCR assay had limit of detection 95% of about 9 genome equivalents by testing serial dilutions of a standard DNA. The detection endpoint of the assay for detection of MS genomic DNA was comparable to a reference real-time PCR. The assay did not crossreact with other important avian pathogens, including avian reovirus, Mycoplasma gallisepticum, Staphylococcus aureus, Escherichia coli, Pasteurella multocida, and Salmonella Pullorum. When 92 synovial fluid and respiratory tract swab samples collected from chickens, turkeys, and geese suspected of MS infection were tested, the clinical performance of the MS iiPCR had 97.8% agreement (Cohen's kappa value, 0.95) with that of the reference real-time PCR. In conclusion, the MS iiPCR/POCKIT™ system, working with field-deployable manual or automatic nucleic acid extraction methods, has potential to serve as a rapid and sensitive on-site tool to facilitate timely detection of MS. © The Author 2016. Published by Oxford University Press on behalf of Poultry Science Association.

  4. Rapid and quantitative detection of Fusarium oxysporum f. sp. cubense race 4 in soil by real-time fluorescence loop-mediated isothermal amplification.

    Science.gov (United States)

    Peng, Jun; Zhang, He; Chen, Fengping; Zhang, Xin; Xie, Yixian; Hou, Xianwen; Li, Guangyi; Pu, Jinji

    2014-12-01

    In this study, a real-time fluorescence loop-mediated isothermal amplification (RealAmp) was developed and evaluated for the rapid and quantitative detection of Fusarium oxysporum f. sp. cubense race 4 (R4) in soil. The LAMP primer set was designed based on previously verified RAPD marker sequences, and the RealAmp assay could specifically detect and distinguish R4 isolates from other related species. The detection sensitivity of the RealAmp assay was approx. 3·82 × 10(3) copies of plasmid DNA or 10(3) of spores per gram in artificially infested soil, indicating that the method is highly tolerant to inhibitor substances in soil compared to real-time PCR. Combining previously published TR4-specific detection methods with the newly established R4-specific RealAmp assay, an indirect approach to detect and differentiate ST4 isolates was achieved by comparing the detection results of R4 and TR4 simultaneously. The existence of ST4 isolates in China was subsequently confirmed through the developed approach. The developed RealAmp assay has been confirmed to be a simple, rapid and effective method to detect R4 in soil, which facilitates to further identify and distinguish ST4 isolates through the comparative analysis of detection results between TR4 and R4 simultaneously. The technique is an alternative quantitative detection method, which will be used for a routine detection service for the soil-borne pathogen in China. © 2014 The Society for Applied Microbiology.

  5. Rapid detection of Salmonella in food and feed by coupling loop-mediated isothermal amplification with bioluminescent assay in real-time.

    Science.gov (United States)

    Yang, Qianru; Domesle, Kelly J; Wang, Fei; Ge, Beilei

    2016-06-17

    Salmonella is among the most significant pathogens causing food and feed safety concerns. This study examined the rapid detection of Salmonella in various types of food and feed samples by coupling loop-mediated isothermal amplification (LAMP) with a novel reporter, bioluminescent assay in real-time (BART). Performance of the LAMP-BART assay was compared to a conventional LAMP and the commercially available 3M Molecular Detection Assay (MDA) Salmonella. The LAMP-BART assay was 100 % specific among 178 strains (151 Salmonella and 27 non-Salmonella) tested. The detection limits were 36 cells per reaction in pure culture and 10(4) to 10(6) CFU per 25 g in spiked food and feed samples without enrichment, which were comparable to those of the conventional LAMP and 3M MDA Salmonella but 5-10 min faster. Ground turkey showed a strong inhibition on 3M MDA Salmonella, requiring at least 10(8) CFU per 25 g for detection. The correlation between Salmonella cell numbers and LAMP-BART signals was high (R (2) = 0.941-0.962), suggesting good quantification capability. After 24 h enrichment, all three assays accurately detected 1 to 3 CFU per 25 g of Salmonella among five types of food (cantaloupe, ground beef, ground turkey, shell eggs, and tomato) and three types of feed (cattle feed, chicken feed, and dry dog food) examined. However, 10(1) CFU per 25 g was required for cattle feed when tested by 3M MDA Salmonella. The Salmonella LAMP-BART assay was rapid, specific, sensitive, quantitative, and robust. Upon further validation, it may become a valuable tool for routine screening of Salmonella in various types of food and feed samples.

  6. An insulated isothermal PCR method on a field-deployable device for rapid and sensitive detection of canine parvovirus type 2 at points of need.

    Science.gov (United States)

    Wilkes, Rebecca P; Lee, Pei-Yu A; Tsai, Yun-Long; Tsai, Chuan-Fu; Chang, Hsiu-Hui; Chang, Hsiao-Fen G; Wang, Hwa-Tang T

    2015-08-01

    Canine parvovirus type 2 (CPV-2), including subtypes 2a, 2b and 2c, causes an acute enteric disease in both domestic and wild animals. Rapid and sensitive diagnosis aids effective disease management at points of need (PON). A commercially available, field-deployable and user-friendly system, designed with insulated isothermal PCR (iiPCR) technology, displays excellent sensitivity and specificity for nucleic acid detection. An iiPCR method was developed for on-site detection of all circulating CPV-2 strains. Limit of detection was determined using plasmid DNA. CPV-2a, 2b and 2c strains, a feline panleukopenia virus (FPV) strain, and nine canine pathogens were tested to evaluate assay specificity. Reaction sensitivity and performance were compared with an in-house real-time PCR using serial dilutions of a CPV-2b strain and 100 canine fecal clinical samples collected from 2010 to 2014, respectively. The 95% limit of detection of the iiPCR method was 13 copies of standard DNA and detection limits for CPV-2b DNA were equivalent for iiPCR and real-time PCR. The iiPCR reaction detected CPV-2a, 2b and 2c and FPV. Non-targeted pathogens were not detected. Test results of real-time PCR and iiPCR from 99 fecal samples agreed with each other, while one real-time PCR-positive sample tested negative by iiPCR. Therefore, excellent agreement (k = 0.98) with sensitivity of 98.41% and specificity of 100% in detecting CPV-2 in feces was found between the two methods. In conclusion, the iiPCR system has potential to serve as a useful tool for rapid and accurate PON, molecular detection of CPV-2. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

  7. Reverse transcription loop-mediated isothermal amplification assays for rapid identification of eastern and western strains of bluetongue virus in India.

    Science.gov (United States)

    Maan, S; Maan, N S; Batra, K; Kumar, A; Gupta, A; Rao, Panduranga P; Hemadri, Divakar; Reddy, Yella Narasimha; Guimera, M; Belaganahalli, M N; Mertens, P P C

    2016-08-01

    Bluetongue virus (BTV) infects all ruminants, including cattle, goats and camelids, causing bluetongue disease (BT) that is often severe in naïve deer and sheep. Reverse-transcription-loop-mediated-isothermal-amplification (RT-LAMP) assays were developed to detect eastern or western topotype of BTV strains circulating in India. Each assay uses four primers recognizing six distinct sequences of BTV genome-segment 1 (Seg-1). The eastern (e)RT-LAMP and western (w)RT-LAMP assay detected BTV RNA in all positive isolates that were tested (n=52, including Indian BTV-1, -2, -3, -5, -9, -10, -16, -21 -23, and -24 strains) with high specificity and efficiency. The analytical sensitivity of the RT-LAMP assays is comparable to real-time RT-PCR, but higher than conventional RT-PCR. The accelerated eRT-LAMP and wRT-LAMP assays generated detectable levels of amplified DNA, down to 0.216 fg of BTV RNA template or 108 fg of BTV RNA template within 60-90min respectively. The assays gave negative results with RNA from foot-and-mouth-disease virus (FMDV), peste des petits ruminants virus (PPRV), or DNA from Capripox viruses and Orf virus (n=10), all of which can cause clinical signs similar to BT. Both RT-LAMP assays did not show any cross-reaction among themselves. The assays are rapid, easy to perform, could be adapted as a 'penside' test making them suitable for 'front-line' diagnosis, helping to identify and contain field outbreaks of BTV. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. Development of a loop-mediated isothermal amplification technique and comparison with quantitative real-time PCR for the rapid visual detection of canine neosporosis.

    Science.gov (United States)

    Mahittikorn, Aongart; Thammasonthijarern, Nipa; Roobthaisong, Amonrattana; Udonsom, Ruenruetai; Popruk, Supaluk; Siri, Sukhontha; Mori, Hirotake; Sukthana, Yaowalark

    2017-08-23

    Dogs are the definitive hosts of Neospora caninum and play an important role in the transmission of the parasite. Despite the high sensitivity of existing molecular tools such as quantitative real-time PCR (qPCR), these techniques are not suitable for use in many countries because of equipment costs and difficulties in implementing them for field diagnostics. Therefore, we developed a simplified technique, loop-mediated isothermal amplification (LAMP), for the rapid visual detection of N. caninum. LAMP specificity was evaluated using a panel containing DNA from a range of different organisms. Sensitivity was evaluated by preparing 10-fold serial dilutions of N. caninum tachyzoites and comparing the results with those obtained using qPCR. Assessment of the LAMP results was determined by recognition of a colour change after amplification. The usefulness of the LAMP assay in the field was tested on 396 blood and 115 faecal samples from dogs, and one placenta from a heifer collected in Lopburi, Nakhon Pathom, Sa Kaeo, and Ratchaburi provinces, Thailand. Specificity of the LAMP technique was shown by its inability to amplify DNA from non-target pathogens or healthy dogs. The detection limit was the equivalent of one genome for both LAMP and qPCR. LAMP and qPCR detected positive N. caninum infection in 15 of 396 (3.8%) blood samples; LAMP detected 9/115 (7.8%) positive faecal samples, while qPCR detected 5/115 (4.3%) positive faecal samples. The placental tissue was shown to be positive by both techniques. Agreement between LAMP and qPCR was perfect in blood samples (kappa value, 1.00) and substantial in faecal samples (kappa value, 0.697). This is the first known LAMP assay developed for the amplification of N. caninum. The technique effectively and rapidly detected the parasite with high sensitivity and specificity and was cost-effective. This assay could be used in the field to confirm the diagnosis of canine or bovine neosporosis.

  9. Ti-thickness-dependent electromigration resistance for Ti/Al-Cu-Si metallization with and without barrier rapid-thermal-anneal in an ammonia ambient

    Science.gov (United States)

    Fu, Kuan Y.; Kawasaki, Hisao; Olowolafe, Johnson O.; Pyle, Ronald E.

    1993-05-01

    The electromigration resistance for Al-Cu-Si alloy over a Ti underlayer as a function of the initial Ti thickness in the range of 0 angstroms - 1000 angstroms is investigated. After the Ti deposition, test structures have been divided into groups with and without a rapid thermal anneal (RTA) in an ammonia ambient to form a TiN barrier. The electromigration resistance of these barrier metallization systems, in general, increases with the initial Ti thickness, except when the initial Ti thickness is less than 600 angstroms for the RTA TiN/Al-Cu-Si system. A model is proposed to explain this electromigration characteristic as a function of the initial Ti thickness for these barrier metallization systems, with the support of texture analysis of the Al-alloy surface and stress measurements of barrier layers using X-ray diffraction and wafer curvature. This study highlights a direction of how a Ti-based barrier metallization system should be processed in order to optimize its electromigration resistance.

  10. Fabrication of a Cu(InGaSe2 Thin Film Photovoltaic Absorber by Rapid Thermal Annealing of CuGa/In Precursors Coated with a Se Layer

    Directory of Open Access Journals (Sweden)

    Chun-Yao Hsu

    2013-01-01

    Full Text Available Cu(InGaSe2 (CIGS thin film absorbers are prepared using sputtering and selenization processes. The CuGa/In precursors are selenized during rapid thermal annealing (RTA, by the deposition of a Se layer on them. This work investigates the effect of the Cu content in precursors on the structural and electrical properties of the absorber. Using X-ray diffraction, field emission scanning electron microscopy, Raman spectroscopy, and Hall effect measurement, it is found that the CIGS thin films produced exhibit facetted grains and a single chalcopyrite phase with a preferred orientation along the (1 1 2 plane. A Cu-poor precursor with a Cu/( ratio of 0.75 demonstrates a higher resistance, due to an increase in the grain boundary scattering and a reduced carrier lifetime. A Cu-rich precursor with a Cu/( ratio of 1.15 exhibits an inappropriate second phase ( in the absorber. However, the precursor with a Cu/( ratio of 0.95 exhibits larger grains and lower resistance, which is suitable for its application to solar cells. The deposition of this precursor on Mo-coated soda lime glass substrate and further RTA causes the formation of a MoSe2 layer at the interface of the Mo and CIGS.

  11. Nitrogen Gas Flow Ratio and Rapid Thermal Annealing Temperature Dependences of Sputtered Titanium Nitride Gate Work Function and Their Effect on Device Characteristics

    Science.gov (United States)

    Liu, Yongxun; Hayashida, Tetsuro; Matsukawa, Takashi; Endo, Kazuhiko; Masahara, Meishoku; O'uchi, Shinich; Sakamoto, Kunihiro; Ishii, Kenichi; Tsukada, Junichi; Ishikawa, Yuki; Yamauchi, Hiromi; Ogura, Atsushi; Suzuki, Eiichi

    2008-04-01

    A sputtered titanium nitride (TiN) metal gate has systematically been investigated, and the dependences of TiN work function (φTiN) and device performance on nitrogen gas flow ratio [RN=N2/(N2+Ar)] in sputtering and rapid thermal annealing (RTA) temperature (TR) are clarified. It is experimentally found that φTiN slightly decreases from 4.87 to 4.78 eV with increasing RN from 17 to 83%, and it markedly decreases with increasing TR. The analysis of the electrical characteristics of fabricated metal-oxide-semiconductor field-effect transistors (MOSFETs) shows that the optimal RN range is 17-50%, and a higher RN offers a lower Vth owing to the lower φTiN. The origin of φTiN decrease with increasing RN and TR is discussed. The obtained results indicate that φTiN can be controlled by sputtering and RTA conditions, and are very useful for setting the appropriate Vth for lightly doped channel devices such as a FinFET.

  12. UV-pretreatment- and near-infrared rapid thermal annealing-enhanced dehydrogenation for a-Si:H thin films at 400 °C

    Energy Technology Data Exchange (ETDEWEB)

    Ji, Sanghyun [AP Systems Corp., 15-5 Dongtansandan 8-gil, Dongtanmyeon, Hwaseongsi, Gyeonggido 445-811 (Korea, Republic of); Dept. of Chem. and Biomol. Engng., Sogang Univ., 35 Baekbeomro, Mapogu, Seoul 121-742 (Korea, Republic of); Hwang, Chi-Sun [ETRI, 138 Gajeongro, Yuseonggu, Daejeon 305-350 (Korea, Republic of); Jeong, Pilseong; Lee, Sungyong [AP Systems Corp., 15-5 Dongtansandan 8-gil, Dongtanmyeon, Hwaseongsi, Gyeonggido 445-811 (Korea, Republic of); Lee, Kwang Soon, E-mail: kslee@sogang.ac.kr [Dept. of Chem. and Biomol. Engng., Sogang Univ., 35 Baekbeomro, Mapogu, Seoul 121-742 (Korea, Republic of)

    2016-01-01

    A new dehydrogenation processing method was developed for the low-temperature polysilicon process. This method can reduce both the process temperature and time through the combination of an ultraviolet pretreatment (UVP) process with near-infrared rapid thermal annealing (NIR-RTA). NIR-RTA using tungsten-halogen lamps was observed to reduce the dehydrogenation time by approximately two thirds and the temperature by approximately 20 °C compared to conventional furnace processing. The UVP process was able to lower the dehydrogenation temperature by a further 20 °C. Thus, the new dehydrogenation process, consisting of UVP followed by NIR-RTA, could achieve a hydrogen concentration of 1.97 at.% in 20 min at 360 °C. - Highlights: • An enhanced dehydrogenation process for flexible substrates as well as glass substrates is proposed.. • UV pretreatment and NIR-RTA are used.. • Temperature of the LTPS process for a-Si:H thin films could be reduced by 40 °C.. • Dehydrogenation time of the LTPS process could be reduced by 20 min..

  13. ZnO nanorod arrays prepared by chemical bath deposition combined with rapid thermal annealing: structural, photoluminescence and field emission characteristics

    Science.gov (United States)

    Chen, Hung-Wei; Yang, Hsi-Wen; He, Hsin-Min; Lee, Yi-Mu

    2016-01-01

    ZnO nanorod arrays were prepared by low temperature chemical bath deposition (CBD) combined with rapid thermal annealing (RTA) under different ambient conditions. The structure and morphology of the synthesized ZnO have been characterized by field-emission scanning electron microscopy (FESEM) and x-ray diffraction (XRD). The obtained ZnO samples are highly crystalline with a hexagonal wurtzite phase and also display well-aligned array structure. A pronounced effect on increased nanorod length was found for the RTA-treated ZnO as compared to the as-grown ZnO. Analysis of XRD indicates that the (0 0 2) feature peak of the as-grown ZnO was shifted towards a lower angle as compared to the peaks of RTA-treated ZnO samples due to the reduction of tensile strain along the c-axis by RTA. Photoluminescence (PL) studies reveal that the ZnO nanorod arrays receiving RTA in an O2 environment have the sharpest UV emission band and greatest intensity ratio of near band-edge emission (NBE) to deep level emission (DLE). Additionally, the effects of RTA on the field emission properties were evaluated. The results demonstrate that RTA an O2 environment can lower the turn-on field and improve the field enhancement factor. The stability of the field emission current was also tested for 4 h.

  14. Improved ground-state modulation characteristics in 1.3 μm InAs/GaAs quantum dot lasers by rapid thermal annealing

    Directory of Open Access Journals (Sweden)

    Ngo Chun

    2011-01-01

    Full Text Available Abstract We investigated the ground-state (GS modulation characteristics of 1.3 μm InAs/GaAs quantum dot (QD lasers that consist of either as-grown or annealed QDs. The choice of annealing conditions was determined from our recently reported results. With reference to the as-grown QD lasers, one obtains approximately 18% improvement in the modulation bandwidth from the annealed QD lasers. In addition, the modulation efficiency of the annealed QD lasers improves by approximately 45% as compared to the as-grown ones. The observed improvements are due to (1 the removal of defects which act as nonradiative recombination centers in the QD structure and (2 the reduction in the Auger-related recombination processes upon annealing.

  15. Available area isotherm

    NARCIS (Netherlands)

    Bosma, JC; Wesselingh, JA

    A new isotherm is presented for adsorption of proteins, the available area isotherm. This isotherm has a steric basis, unlike the (steric) mass action model. The shape of the available area isotherm is determined only by geometric exclusion. With the new isotherm, experimental results can be fitted

  16. Surface morphological, electrical and transport properties of rapidly annealed double layers Ru/Cr Schottky structure on n-type InP

    Science.gov (United States)

    Shanthi Latha, K.; Rajagopal Reddy, V.

    2017-07-01

    The electrical and transport properties of a fabricated bilayer Ru/Cr/ n-InP Schottky diode (SD) have been investigated at different annealing temperatures. Atomic force microscopy results have showed that the overall surface morphology of the Ru/Cr/ n-InP SD is fairly smooth at elevated temperatures. High barrier height is achieved for the diode annealed at 300 °C compared to the as-deposited, annealed at 200 and 400 °C diodes. The series resistance and shunt resistance of the Ru/Cr/ n-InP SD are estimated by current-voltage method at different annealing temperatures. The barrier heights and series resistance are also determined by Cheung's and modified Norde functions. The interface state density of the Ru/Cr/ n-InP SD is found to be decreased after annealing at 300 °C and then slightly increased upon annealing at 400 °C. The difference between barrier heights obtained from current-voltage and capacitance-voltage is also discussed. Experimental results have showed that the Poole-Frenkel emission is found to be dominant in the lower bias region whereas Schottky emission is dominant in the higher bias region for the Ru/Cr/ n-InP SDs irrespective of annealing temperatures.

  17. Rapid detection of equine influenza virus H3N8 subtype by insulated isothermal RT-PCR (iiRT-PCR) assay using the POCKIT™ Nucleic Acid Analyzer.

    Science.gov (United States)

    Balasuriya, Udeni B R; Lee, Pei-Yu Alison; Tiwari, Ashish; Skillman, Ashley; Nam, Bora; Chambers, Thomas M; Tsai, Yun-Long; Ma, Li-Juan; Yang, Pai-Chun; Chang, Hsiao-Fen Grace; Wang, Hwa-Tang Thomas

    2014-10-01

    Equine influenza (EI) is an acute, highly contagious viral respiratory disease of equids. Currently, equine influenza virus (EIV) subtype H3N8 continues to be the most important respiratory pathogen of horses in many countries around the world. The need to achieve a rapid diagnosis and to implement effective quarantine and movement restrictions is critical in controlling the spread of EIV. In this study, a novel, inexpensive and user-friendly assay based on an insulated isothermal RT-PCR (iiRT-PCR) method on the POCKIT™, a field-deployable device, was described and validated for point-of-need detection of EIV-H3N8 in clinical samples. The newly established iiRT-PCR assay targeting the EIV HA3 gene was evaluated for its sensitivity using in vitro transcribed (IVT) RNA, as well as ten-fold serial dilutions of RNA extracted from the prototype H3N8 strain A/equine/Miami/1/63. Inclusivity and exclusivity panels were tested for specificity evaluation. Published real-time RT-PCR (rRT-PCR) assays targeting the NP and HA3 genes were used as the reference standards for comparison of RNA extracted from field strains and from nasal swab samples collected from experimentally infected horses, respectively. Limit of detection with a 95% probability (LoD95%) was estimated to be 11copies of IVT RNA. Clinical sensitivity analysis using RNA prepared from serial dilutions of a prototype EIV (Miami 1/63/H3N8) showed that the iiRT-PCR assay was about 100-fold more sensitive than the rRT-PCR assay targeting the NP gene of EIV subtype H3N8. The iiRT-PCR assay identified accurately fifteen EIV H3N8 strains and two canine influenza virus (CIV) H3N8 strains, and did not cross-react with H6N2, H7N7, H1N1 subtypes or any other equine respiratory viral pathogens. Finally, 100% agreement was found between the iiRT-PCR assay and the universal influenza virus type A rRT-PCR assay in detecting the EIV A/equine/Kentucky/7/07 strain in 56 nasal swab samples collected from experimentally inoculated

  18. The Development and Evaluation of a Loop-Mediated Isothermal Amplification Method for the Rapid Detection of Salmonella enterica serovar Typhi.

    Directory of Open Access Journals (Sweden)

    Fenxia Fan

    Full Text Available Typhoid fever remains a public health threat in many countries. A positive result in traditional culture is a gold-standard for typhoid diagnosis, but this method is time consuming and not sensitive enough for detection of samples containing a low copy number of the target organism. The availability of the loop-mediated isothermal amplification (LAMP assay, which offers high speed and simplicity in detection of specific targets, has vastly improved the diagnosis of numerous infectious diseases. However, little research efforts have been made on utilizing this approach for diagnosis of Salmonella enterica serovar Typhi by targeting a single and specific gene. In this study, a LAMP assay for rapid detection of S. Typhi based on a novel marker gene, termed STY2879-LAMP, was established and evaluated with real-time PCR (RT-PCR. The specificity tests showed that STY2879 could be amplified in all S. Typhi strains isolated in different years and regions in China, whereas no amplification was observable in non-typhoidal strains covering 34 Salmonella serotypes and other pathogens causing febrile illness. The detection limit of STY2879-LAMP for S. Typhi was 15 copies/reaction in reference plasmids, 200 CFU/g with simple heat-treatment of DNA extracted from simulated stool samples and 20 CFU/ml with DNA extracted from simulated blood samples, which was 10 fold more sensitive than the parallel RT-PCR control experiment. Furthermore, the sensitivity of STY2879-LAMP and RT-PCR combining the traditional culture enrichment method for simulated stool and blood spiked with lower S. Typhi count during the 10 h enrichment time was also determined. In comparison with LAMP, the positive reaction time for RT-PCR required additional 2-3 h enrichment time for either simulated stool or blood specimens. Therefore, STY2879-LAMP is of practical value in the clinical settings and has a good potential for application in developing regions due to its easy-to-use protocol.

  19. Electrical and structural properties of (Pd/Au) Schottky contact to as grown and rapid thermally annealed GaN grown by MBE

    Energy Technology Data Exchange (ETDEWEB)

    Nirwal, Varun Singh, E-mail: varun.nirwal30@gmail.com; Singh, Joginder; Gautam, Khyati; Peta, Koteswara Rao [Department of Electronic Science, University of Delhi South Campus, Benito Juarez Road, New Delhi-110021 (India)

    2016-05-06

    We studied effect of thermally annealed GaN surface on the electrical and structural properties of (Pd/Au) Schottky contact to Ga-polar GaN grown by molecular beam epitaxy on Si substrate. Current voltage (I-V) measurement was used to study electrical properties while X-ray diffraction (XRD) measurement was used to study structural properties. The Schottky barrier height calculated using I-V characteristics was 0.59 eV for (Pd/Au) Schottky contact on as grown GaN, which increased to 0.73 eV for the Schottky contact fabricated on 700 °C annealed GaN film. The reverse bias leakage current at -1 V was also significantly reduced from 6.42×10{sup −5} A to 7.31×10{sup −7} A after annealing. The value of series resistance (Rs) was extracted from Cheung method and the value of R{sub s} decreased from 373 Ω to 172 Ω after annealing. XRD results revealed the formation of gallide phases at the interface of (Pd/Au) and GaN for annealed sample, which could be the reason for improvement in the electrical properties of Schottky contact after annealing.

  20. Rapid and sensitive detection of Mycoplasma synoviae by an insulated isothermal polymerase chain reaction-based assay on a field-deployable device

    OpenAIRE

    Kuo, Hung-Chih; Lo, Dan-Yuan; Chen, Chiou-Lin; Tsai, Yun-Long; Ping, Jia-Fong; Lee, Chien-Hsien; Lee, Pei-Yu Alison; Chang, Hsiao-Fen Grace

    2016-01-01

    Mycoplasma synoviae (MS), causing respiratory diseases, arthritis, and eggshell apex abnormalities in avian species, is an important pathogen in the poultry industry. Implementation of a biosecurity plan is important in MS infection management. Working on a field-deployable POCKIT? device, an insulated isothermal polymerase chain reaction (iiPCR) assay has a potential for timely MS detection on the farm. The MS iiPCR assay had limit of detection 95% of about 9 genome equivalents by testing se...

  1. Structural, electrical, and surface morphological characteristics of rapidly annealed Pt/Ti Schottky contacts to n-type InP

    Energy Technology Data Exchange (ETDEWEB)

    Reddy, V. Rajagopal; Reddy, D. Subba; Naik, S. Sankar [Department of Physics, Sri Venkateswara University, Tirupati (India); Choi, C.J. [School of Semiconductor and Chemical Engineering, Semiconductor Physics Research Center (SPRC), Chonbuk National University, Jeonju (Korea, Republic of)

    2011-10-15

    We have investigated the electrical and structural properties of Pt/Ti metallization scheme on n-type InP as a function of annealing temperature using current-voltage (I-V), capacitance-voltage (C-V), Auger electron spectroscopy (AES), and X-ray diffraction (XRD) measurements. Measurements showed that barrier height of as-deposited Pt/Ti Schottky contact is 0.62 eV (I-V) and 0.76 eV (C-V). Experimental results indicate that high-quality Schottky contact with barrier height and ideality factor of 0.66 eV (I-V), 0.80 eV (C-V), and 1.14 can be achieved after annealing at 400 C for 1 min in N{sub 2} atmosphere. Further, it is observed that the barrier height slightly decreases to 0.55 eV (I-V) and 0.71 eV (C-V) after annealing at 500 C. Norde method is also employed to calculate the barrier height of Pt/Ti Schottky contacts. The obtained values are in good agreement with those obtained by I-V measurements. These results indicate that the optimum annealing temperature for the Pt/Ti Schottky contact is 400 C. According to AES and XRD analysis, the formation of indium phases at the Pt/Ti/n-InP interface could be the reason for the increase of Schottky barrier height (SBH) after annealing at 400 C. Results also showed the formation of phosphide phases at the interface. This may be the reason for the decrease in the barrier height after annealing at 500 C. The AFM results showed that the overall surface morphology of Pt/Ti Schottky contact is reasonably smooth. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  2. Influence of homo-buffer layers and post-deposition rapid thermal annealing upon atomic layer deposition grown ZnO at 100 °C with three-pulsed precursors per growth cycle

    Science.gov (United States)

    Cheng, Yung-Chen; Yuan, Kai-Yun; Chen, Miin-Jang

    2017-10-01

    ZnO main epilayers are deposited with three-pulsed precursors in every growth cycle at 100 °C on various thicknesses of 300 °C-grown homo-buffer layers by atomic layer deposition (ALD) on sapphire substrate. Samples are treated without and with post-deposition rapid thermal annealing (RTA). Two different annealing temperatures 300 and 1000 °C are utilized in the ambience of oxygen for 5 min. Extremely low background electron concentration 8.4 × 1014 cm-3, high electron mobility 62.1 cm2/V s, and pronounced enhancement of near bandgap edge photoluminescence (PL) are achieved for ZnO main epilayer with sufficient thickness of buffer layer (200 ALD cycles) and post-deposition RTA at 1000 °C. Effective block and remove of thermally unstable mobile defects and other crystal lattice imperfections are the agents of quality promotion of ZnO thin film.

  3. The development of loop-mediated isothermal amplification (LAMP) assays for the rapid authentication of five forbidden vegetables in strict vegetarian diets

    OpenAIRE

    Meng-Shiou Lee; Ting-Ying Su; Yi-Yang Lien; Shyang-Chwen Sheu

    2017-01-01

    Plant-based food ingredients such as garlic, Chinese leek, Chinese onion, green onion and onion are widely used in many cuisines around the world. However, these ingredients known as the ?five forbidden vegetables? (FFVs) are not allowed in some vegetarian diets. In this study, a loop-mediated isothermal amplification (LAMP) assay was developed for the detection of FFVs using five respective LAMP primer sets. The specific primers targeted the ITS1-5.8S-ITS2 nuclear ribosomal DNA sequence regi...

  4. Rapid adsorption of copper(II and lead(II by rice straw/Fe₃O₄ nanocomposite: optimization, equilibrium isotherms, and adsorption kinetics study.

    Directory of Open Access Journals (Sweden)

    Roshanak Khandanlou

    Full Text Available Rice straw/magnetic nanocomposites (RS/Fe3O4-NCs were prepared via co-precipitation method for removal of Pb(II and Cu(II from aqueous solutions. Response surface methodology (RSM was utilized to find the optimum conditions for removal of ions. The effects of three independent variables including initial ion concentration, removal time, and adsorbent dosage were investigated on the maximum adsorption of Pb (II and Cu (II. The optimum conditions for the adsorption of Pb(II and Cu(II were obtained (100 and 60 mg/L of initial ion concentration, (41.96 and 59.35 s of removal time and 0.13 g of adsorbent for both ions, respectively. The maximum removal efficiencies of Pb(II and Cu(II were obtained 96.25% and 75.54%, respectively. In the equilibrium isotherm study, the adsorption data fitted well with the Langmuir isotherm model. The adsorption kinetics was best depicted by the pseudo-second order model. Desorption experiments showed adsorbent can be reused successfully for three adsorption-desorption cycles.

  5. One simple DNA extraction device and its combination with modified visual loop-mediated isothermal amplification for rapid on-field detection of genetically modified organisms.

    Science.gov (United States)

    Zhang, Miao; Liu, Yinan; Chen, Lili; Quan, Sheng; Jiang, Shimeng; Zhang, Dabing; Yang, Litao

    2013-01-02

    Quickness, simplicity, and effectiveness are the three major criteria for establishing a good molecular diagnosis method in many fields. Herein we report a novel detection system for genetically modified organisms (GMOs), which can be utilized to perform both on-field quick screening and routine laboratory diagnosis. In this system, a newly designed inexpensive DNA extraction device was used in combination with a modified visual loop-mediated isothermal amplification (vLAMP) assay. The main parts of the DNA extraction device included a silica gel membrane filtration column and a modified syringe. The DNA extraction device could be easily operated without using other laboratory instruments, making it applicable to an on-field GMO test. High-quality genomic DNA (gDNA) suitable for polymerase chain reaction (PCR) and isothermal amplification could be quickly isolated from plant tissues using this device within 15 min. In the modified vLAMP assay, a microcrystalline wax encapsulated detection bead containing SYBR green fluorescent dye was introduced to avoid dye inhibition and cross-contaminations from post-LAMP operation. The system was successfully applied and validated in screening and identification of GM rice, soybean, and maize samples collected from both field testing and the Grain Inspection, Packers, and Stockyards Administration (GIPSA) proficiency test program, which demonstrated that it was well-adapted to both on-field testing and/or routine laboratory analysis of GMOs.

  6. Impact of ink synthesis on processing of inkjet-printed silicon nanoparticle thin films: A comparison of Rapid Thermal Annealing and photonic sintering

    Energy Technology Data Exchange (ETDEWEB)

    Drahi, E.; Blayac, S. [Centre Microélectronique de Provence/Ecole Nationale Supérieure des Mines de Saint Etienne, 880, avenue de Mimet Gardanne, 13541 (France); Borbely, A. [Science des Matériaux et des Structures/Ecole Nationale Supérieure des Mines de Saint Etienne, 158, cours Fauriel Saint Etienne Cedex 2, 42023 (France); Benaben, P. [Centre Microélectronique de Provence/Ecole Nationale Supérieure des Mines de Saint Etienne, 880, avenue de Mimet Gardanne, 13541 (France)

    2015-01-01

    Inkjet printing has a high potential for cost reduction in solar cell and thermoelectric industry. This study demonstrates that silicon thin films can be produced by inkjet-printing of silicon nanoparticles followed by subsequent drying and annealing steps. Ink formulation is crucial for the sintering of the silicon nanoparticles and control of the microstructure at low temperature. Upon heating, the microstructure is modified from porous layer made of juxtaposed silicon nanoparticles to denser layer with coarser grains. This evolution is monitored by scanning electron microscopy and by micro-Raman spectroscopy, which offer a fast and precise characterization of the microstructure and chemical composition of thin films. Above a threshold temperature of 800 °C cracks appear within thin film and substrate because of the stress induced by the oxidation of the surface. An innovative sintering method, photonic annealing, is studied in order to reduce both oxidation and stress in the thin films as well as reducing processing time. Evolution of the thermal conductivity is performed by micro-Raman spectroscopy and can be tailored in a large range between ~ 1 and ~ 100 W·m{sup −1}·K{sup −1} depending on the sintering method and atmosphere. Therefore control of the microstructure evolution with applied annealing process allows tailoring of both microstructure and thermal conductivity of the silicon thin films. - Highlights: • Impact of ink synthesis on sintering (Si nanoparticle surface chemistry) • Photonic annealing of inkjet printed Si nanoparticles • Micro-Raman spectroscopy and X-Ray Diffraction for thin film characterization.

  7. Loop-Mediated Isothermal Amplification (LAMP) for Rapid Detection and Quantification of Dehalococcoides Biomarker Genes in Commercial Reductive Dechlorinating Cultures KB-1 and SDC-9.

    Science.gov (United States)

    Kanitkar, Yogendra H; Stedtfeld, Robert D; Steffan, Robert J; Hashsham, Syed A; Cupples, Alison M

    2016-01-08

    Real-time quantitative PCR (qPCR) protocols specific to the reductive dehalogenase (RDase) genes vcrA, bvcA, and tceA are commonly used to quantify Dehalococcoides spp. in groundwater from chlorinated solvent-contaminated sites. In this study, loop-mediated isothermal amplification (LAMP) was developed as an alternative approach for the quantification of these genes. LAMP does not require a real-time thermal cycler (i.e., amplification is isothermal), allowing the method to be performed using less-expensive and potentially field-deployable detection devices. Six LAMP primers were designed for each of three RDase genes (vcrA, bvcA, and tceA) using Primer Explorer V4. The LAMP assays were compared to conventional qPCR approaches using plasmid standards, two commercially available bioaugmentation cultures, KB-1 and SDC-9 (both contain Dehalococcoides species). DNA was extracted over a growth cycle from KB-1 and SDC-9 cultures amended with trichloroethene and vinyl chloride, respectively. All three genes were quantified for KB-1, whereas only vcrA was quantified for SDC-9. A comparison of LAMP and qPCR using standard plasmids indicated that quantification results were similar over a large range of gene concentrations. In addition, the quantitative increase in gene concentrations over one growth cycle of KB-1 and SDC-9 using LAMP was comparable to that of qPCR. The developed LAMP assays for vcrA and tceA genes were validated by comparing quantification on the Gene-Z handheld platform and a real-time thermal cycler using DNA isolated from eight groundwater samples obtained from an SDC-9-bioaugmented site (Tulsa, OK). These assays will be particularly useful at sites subject to bioaugmentation with these two commonly used Dehalococcoides species-containing cultures. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  8. The development of loop-mediated isothermal amplification (LAMP) assays for the rapid authentication of five forbidden vegetables in strict vegetarian diets.

    Science.gov (United States)

    Lee, Meng-Shiou; Su, Ting-Ying; Lien, Yi-Yang; Sheu, Shyang-Chwen

    2017-03-14

    Plant-based food ingredients such as garlic, Chinese leek, Chinese onion, green onion and onion are widely used in many cuisines around the world. However, these ingredients known as the "five forbidden vegetables" (FFVs) are not allowed in some vegetarian diets. In this study, a loop-mediated isothermal amplification (LAMP) assay was developed for the detection of FFVs using five respective LAMP primer sets. The specific primers targeted the ITS1-5.8S-ITS2 nuclear ribosomal DNA sequence regions among the five vegetables. The results demonstrated that the identification of FFVs using the newly developed LAMP assay is more sensitive than the traditional PCR method. Using pepper, basil, parsley, chili and ginger as references, established LAMP primer sets showed high specificity for the identification of the FFV species. Moreover, when FFVs were mixed with other plant ingredients at different ratios (100:0, 50:50, 20:80, 10:90, 5:95, 2:98, and 1:99), no cross-reactivity was evident using LAMP. Finally, genomic DNAs extracted from boiled and steamed FFVs in processed foods were used as templates; the performance of the LAMP reaction was not influenced using validated LAMP primers. Not only can FFV ingredients be identified but commercial foods containing FFVs can also be authenticated. This LAMP method will be useful for the authentication of FFVs in practical food markets in the future.

  9. Development of a rapid, simple method for detecting Naegleria fowleri visually in water samples by loop-mediated isothermal amplification (LAMP.

    Directory of Open Access Journals (Sweden)

    Aongart Mahittikorn

    Full Text Available Naegleria fowleri is the causative agent of the fatal disease primary amebic meningoencephalitis. Detection of N. fowleri using conventional culture and biochemical-based assays is time-consuming and laborious, while molecular techniques, such as PCR, require laboratory skills and expensive equipment. We developed and evaluated a novel loop-mediated isothermal amplification (LAMP assay targeting the virulence-related gene for N. fowleri. Time to results is about 90 min and amplification products were easily detected visually using hydroxy naphthol blue. The LAMP was highly specific after testing against related microorganisms and able to detect one trophozoite, as determined with spiked water and cerebrospinal fluid samples. The assay was then evaluated with a set of 80 water samples collected during the flooding crisis in Thailand in 2011, and 30 natural water samples from border areas of northern, eastern, western, and southern Thailand. N. fowleri was detected in 13 and 10 samples using LAMP and PCR, respectively, with a Kappa coefficient of 0.855. To the best of our knowledge, this is the first report of a LAMP assay for N. fowleri. Due to its simplicity, speed, and high sensitivity, the LAMP method described here might be useful for quickly detecting and diagnosing N. fowleri in water and clinical samples, particularly in resource-poor settings.

  10. Development of a rapid, simple method for detecting Naegleria fowleri visually in water samples by loop-mediated isothermal amplification (LAMP).

    Science.gov (United States)

    Mahittikorn, Aongart; Mori, Hirotake; Popruk, Supaluk; Roobthaisong, Amonrattana; Sutthikornchai, Chantira; Koompapong, Khuanchai; Siri, Sukhontha; Sukthana, Yaowalark; Nacapunchai, Duangporn

    2015-01-01

    Naegleria fowleri is the causative agent of the fatal disease primary amebic meningoencephalitis. Detection of N. fowleri using conventional culture and biochemical-based assays is time-consuming and laborious, while molecular techniques, such as PCR, require laboratory skills and expensive equipment. We developed and evaluated a novel loop-mediated isothermal amplification (LAMP) assay targeting the virulence-related gene for N. fowleri. Time to results is about 90 min and amplification products were easily detected visually using hydroxy naphthol blue. The LAMP was highly specific after testing against related microorganisms and able to detect one trophozoite, as determined with spiked water and cerebrospinal fluid samples. The assay was then evaluated with a set of 80 water samples collected during the flooding crisis in Thailand in 2011, and 30 natural water samples from border areas of northern, eastern, western, and southern Thailand. N. fowleri was detected in 13 and 10 samples using LAMP and PCR, respectively, with a Kappa coefficient of 0.855. To the best of our knowledge, this is the first report of a LAMP assay for N. fowleri. Due to its simplicity, speed, and high sensitivity, the LAMP method described here might be useful for quickly detecting and diagnosing N. fowleri in water and clinical samples, particularly in resource-poor settings.

  11. Rapid detection of Piper yellow mottle virus and Cucumber mosaic virus infecting black pepper (Piper nigrum) by loop-mediated isothermal amplification (LAMP).

    Science.gov (United States)

    Bhat, A I; Siljo, A; Deeshma, K P

    2013-10-01

    The loop-mediated isothermal amplification (LAMP) assay for Piper yellow mottle virus and the reverse transcription (RT) LAMP assay for Cucumber mosaic virus each consisted of a set of five primers designed against the conserved sequences in the viral genome. Both RNA and DNA isolated from black pepper were used as a template for the assay. The results were assessed visually by checking turbidity, green fluorescence and pellet formation in the reaction tube and also by gel electrophoresis. The assay successfully detected both viruses in infected plants whereas no cross-reactions were recorded with healthy plants. Optimum conditions for successful amplification were determined in terms of the concentrations of magnesium sulphate and betaine, temperature, and duration. The detection limit for both LAMP and RT-LAMP was up to 100 times that for conventional PCR and up to one-hundredth of that for real-time PCR. The optimal conditions arrived at were validated by testing field samples of infected vines of three species from different regions. Copyright © 2013 Elsevier B.V. All rights reserved.

  12. Formation of tree-like and vortex magnetic domains of nanocrystalline α-(Fe,Si) in La–Fe–Si ribbons during rapid solidification and subsequent annealing

    Energy Technology Data Exchange (ETDEWEB)

    Hou, Xueling, E-mail: xlhou@staff.shu.edu.cn [Laboratory for Microstructures of Shanghai University, Shanghai 200444 (China); School of Materials Science and Engineering, Shanghai University, Shanghai 200072 China (China); Tian, Yue [Laboratory for Microstructures of Shanghai University, Shanghai 200444 (China); School of Materials Science and Engineering, Shanghai University, Shanghai 200072 China (China); Key Laboratory of Magnetic Materials and Devices, Ningbo Institute of Material Technology and Engineering, CAS, Ningbo 315201 (China); Xue, Yun; Liu, Chunyu [Laboratory for Microstructures of Shanghai University, Shanghai 200444 (China); School of Materials Science and Engineering, Shanghai University, Shanghai 200072 China (China); Xia, Weixing [Key Laboratory of Magnetic Materials and Devices, Ningbo Institute of Material Technology and Engineering, CAS, Ningbo 315201 (China); Xu, Hui [Laboratory for Microstructures of Shanghai University, Shanghai 200444 (China); School of Materials Science and Engineering, Shanghai University, Shanghai 200072 China (China); Lampen-Kelley, Paula, E-mail: plampen@utk.edu [Department of Physics, University of South Florida, Tampa, FL 33620 (United States); Srikanth, Hariharan [Department of Physics, University of South Florida, Tampa, FL 33620 (United States); Phan, Manh-Huong, E-mail: phanm@usf.edu [Department of Physics, University of South Florida, Tampa, FL 33620 (United States)

    2016-06-05

    The characteristic magnetic domains at the surfaces of melt-spun La–Fe–Si ribbons under different thermal processing conditions are explored using room-temperature Lorentz force microscopy and electron holography. In as-quenched ribbons, the magnetic domain structure is found to change from a tree-like morphology on the surface far from the copper wheel during quenching to a vortex-type domain structure on the surface in contact with the wheel. In the initial stages of annealing, domains on both surfaces developed a vortex behavior. Detailed microstructural observations demonstrated nanocrystalline α-(Fe,Si) regions embedded in the majority La(Fe,Si){sub 13} phase due to a partially completed peritectoid reaction between α-(Fe,Si) and LaFeSi. The room temperature magnetic domains disappeared along with the residual α-(Fe,Si) upon extended heat treatment, yielding a homogeneous La(Fe,Si){sub 13} material. Magnetometry measurements and analysis reveal the absence of strong coupling between the α-(Fe,Si) and La(Fe,Si){sub 13} phases, so that the presence of α-(Fe,Si) nanocrystallites with a vortex-type structure does not favor an enhanced magnetocaloric response in the ribbons. - Highlights: • Microstructure and magnetic domain structure investigated in La–Fe–Si ribbons. • Fe magnetic domains transformed from tree-like to vortex-type by annealing. • No magnetic coupling evident between nanocrystalline Fe and La(Fe,Si){sub 13} matrix.

  13. Detection of Magnaporthe oryzae chrysovirus 1 in Japan and establishment of a rapid, sensitive and direct diagnostic method based on reverse transcription loop-mediated isothermal amplification.

    Science.gov (United States)

    Komatsu, Ken; Urayama, Syun-Ichi; Katoh, Yu; Fuji, Shin-Ichi; Hase, Shu; Fukuhara, Toshiyuki; Arie, Tsutomu; Teraoka, Tohru; Moriyama, Hiromitsu

    2016-02-01

    Magnaporthe oryzae chrysovirus 1 (MoCV1) is a mycovirus with a dsRNA genome that infects the rice blast fungus Magnaporthe oryzae and impairs its growth. To date, MoCV1 has only been found in Vietnamese isolates of M. oryzae, and the distribution of this virus in M. oryzae isolates from other parts of the world remains unknown. In this study, using a one-step reverse transcription PCR (RT-PCR) assay, we detected a MoCV1-related virus in M. oryzae in Japan (named MoCV1-AK) whose sequence shares considerable similarity with that of the MoCV1 Vietnamese isolate. To establish a system for a comprehensive survey of MoCV1 infection in the field, we developed a reverse transcription loop-mediated isothermal amplification (RT-LAMP) assay for direct detection of the virus. The sensitivity of the RT-LAMP assay was at least as high as that of the one-step RT-PCR assay. In addition, we detected MoCV1-AK in M. oryzae-infected oatmeal agar plates and lesions on rice leaves using the RT-LAMP assay without dsRNA extraction, by simple sampling with a toothpick. Preliminary screening of MoCV1 in Japanese M. oryzae isolates indicated that MoCV1 is currently distributed in rice fields in Japan. Our results provide a first example of the application of RT-LAMP for the detection of mycoviruses, which will accelerate surveys for mycovirus infection.

  14. Validation of a commercial insulated isothermal PCR-based POCKIT test for rapid and easy detection of white spot syndrome virus infection in Litopenaeus vannamei.

    Directory of Open Access Journals (Sweden)

    Yun-Long Tsai

    Full Text Available Timely pond-side detection of white spot syndrome virus (WSSV plays a critical role in the implementation of bio-security measures to help minimize economic losses caused by white spot syndrome disease, an important threat to shrimp aquaculture industry worldwide. A portable device, namely POCKIT™, became available recently to complete fluorescent probe-based insulated isothermal PCR (iiPCR, and automatic data detection and interpretation within one hour. Taking advantage of this platform, the IQ Plus™ WSSV Kit with POCKIT system was established to allow simple and easy WSSV detection for on-site users. The assay was first evaluated for its analytical sensitivity and specificity performance. The 95% limit of detection (LOD of the assay was 17 copies of WSSV genomic DNA per reaction (95% confidence interval [CI], 13 to 24 copies per reaction. The established assay has detection sensitivity similar to that of OIE-registered IQ2000™ WSSV Detection and Protection System with serial dilutions of WSSV-positive Litopenaeus vannamei DNA. No cross-reaction signals were generated from infectious hypodermal and haematopoietic necrosis virus (IHHNV, monodon baculovirus (MBV, and hepatopancreatic parvovirus (HPV positive samples. Accuracy analysis using 700 L. vannamei of known WSSV infection status shows that the established assayhassensitivity93.5% (95% CI: 90.61-95.56% and specificity 97% (95% CI: 94.31-98.50%. Furthermore, no discrepancy was found between the two assays when 100 random L. vannamei samples were tested in parallel. Finally, excellent correlation was observed among test results of three batches of reagents with 64 samples analyzed in three different laboratories. Working in a portable device, IQ Plus™ WSSV Kit with POCKIT system allows reliable, sensitive and specific on-site detection of WSSV in L. vannamei.

  15. Effects of rapid thermal annealing on structural, chemical, and electrical characteristics of atomic-layer deposited lanthanum doped zirconium dioxide thin film on 4H-SiC substrate

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Way Foong, E-mail: wayfoong317@yahoo.com.sg [Institute of Nano Optoelectronics Research and Technology, School of Physics, Universiti Sains Malaysia, 11800 Penang (Malaysia); Centre for Research Initiatives (CRI) Natural Sciences, Universiti Sains Malaysia, 11800 Penang (Malaysia); Quah, Hock Jin, E-mail: jinquah1st@hotmail.com [Institute of Nano Optoelectronics Research and Technology, School of Physics, Universiti Sains Malaysia, 11800 Penang (Malaysia); Centre for Research Initiatives (CRI) Natural Sciences, Universiti Sains Malaysia, 11800 Penang (Malaysia); Lu, Qifeng, E-mail: Qifeng@liverpool.ac.uk [Department of Electrical Engineering and Electronics, University of Liverpool, Liverpool L69 3GJ (United Kingdom); Mu, Yifei, E-mail: Y.mu@student.liverpool.ac.uk [Department of Electrical Engineering and Electronics, University of Liverpool, Liverpool L69 3GJ (United Kingdom); Ismail, Wan Azli Wan, E-mail: azli.ismail@mimos.my [Advance Analytical Services Lab, MIMOS Wafer Fab, MIMOS Berhad, Technology Park Malaysia, 57000 Kuala Lumpur (Malaysia); Rahim, Bazura Abdul, E-mail: bazura@mimos.my [Advance Analytical Services Lab, MIMOS Wafer Fab, MIMOS Berhad, Technology Park Malaysia, 57000 Kuala Lumpur (Malaysia); Esa, Siti Rahmah, E-mail: rahmah.esa@mimos.my [Advance Analytical Services Lab, MIMOS Wafer Fab, MIMOS Berhad, Technology Park Malaysia, 57000 Kuala Lumpur (Malaysia); Kee, Yeh Yee, E-mail: yy.kee@mimos.my [Advance Analytical Services Lab, MIMOS Wafer Fab, MIMOS Berhad, Technology Park Malaysia, 57000 Kuala Lumpur (Malaysia); Zhao, Ce Zhou, E-mail: cezhou.zhao@xjtlu.edu.cn [Department of Electrical Engineering and Electronics, University of Liverpool, Liverpool L69 3GJ (United Kingdom); Department of Electrical and Electronic Engineering, Xi’an Jiaotong-Liverpool University, Suzhou, Jiangsu 215123 (China); and others

    2016-03-01

    Graphical abstract: - Highlights: • Studies of RTA temperatures on La doped ZrO2 atomic layer deposited on 4HSiC. • Oxygen vacancies improved insulating and catalytic properties of La doped ZrO2. • 700 °C annealed sample showed the highest EB, k value, and sensitivity on O2. • La doped ZrO2 was proposed as a potential metal reactive oxide on 4H-SiC. - Abstract: Effects of rapid thermal annealing at different temperatures (700–900 °C) on structural, chemical, and electrical characteristics of lanthanum (La) doped zirconium oxide (ZrO{sub 2}) atomic layer deposited on 4H-SiC substrates have been investigated. Chemical composition depth profiling analysis using X-ray photoelectron spectroscopy (XPS) and cross-sectional studies using high resolution transmission electron microscopy equipped with energy dispersive X-ray spectroscopy line scan analysis were insufficient to justify the presence of La in the investigated samples. The minute amount of La present in the bulk oxide was confirmed by chemical depth profiles of time-of-flight secondary ion mass spectrometry. The presence of La in the ZrO{sub 2} lattice led to the formation of oxygen vacancies, which was revealed through binding energy shift for XPS O 1s core level spectra of Zr−O. The highest amount of oxygen vacancies in the sample annealed at 700 °C has yielded the acquisition of the highest electric breakdown field (∼ 6.3 MV/cm) and dielectric constant value (k = 23) as well as the highest current–time (I–t) sensor response towards oxygen gas. The attainment of both the insulating and catalytic properties in the La doped ZrO{sub 2} signified the potential of the doped ZrO{sub 2} as a metal reactive oxide on 4H-SiC substrate.

  16. Energy Band Diagram near the Interface of Aluminum Oxide on p-Si Fabricated by Atomic Layer Deposition without/with Rapid Thermal Cycle Annealing Determined by Capacitance-Voltage Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Satoh, N. [Department of Electrical Engineering, Kyoto University, Kyoto (Japan); Cesar, I.; Lamers, M.; Romijn, I.; Bakker, K.; Olson, C.; Oosterling Saynova, D.; Komatsu, Y.; Weeber, A. [ECN Solar Energy, Petten (Netherlands); Verbake, F.; Wiggers, M. [Philips Research, Eindhoven (Netherlands)

    2012-07-01

    We evaluated the fixed charge (Qf) and the interface state density (Dit) from the capacitance-voltage (C-V) measurement before and after rapid thermal cycle annealing (RTCA) using p-type silicon in which the passivation was performed with aluminum oxide (Al2O3) film by atomic layer deposition (ALD). From C-V measurement we obtained the surface potential (VS), accumulation and depletion width, and as a result, energy band diagrams were produced. It was determined that a barrier height of approximately 100 mV was induced by fixed negative charges in the Al2O3 layer near the interface to the p-type Si substrate. The field effect of the Al2O3 passivation layer created by RTCA strongly remains without depending on the gate voltage (VG)

  17. Evaluation of a field-deployable reverse transcription-insulated isothermal PCR for rapid and sensitive on-site detection of Zika virus.

    Science.gov (United States)

    Carossino, Mariano; Li, Yanqiu; Lee, Pei-Yu A; Tsai, Chuan-Fu; Chou, Pin-Hsing; Williams, Dennis; Skillman, Ashley; Frank Cook, R; Brown, Grayson; Chang, Hsiao-Fen G; Wang, Hwa-Tang T; Balasuriya, Udeni B R

    2017-12-19

    The recent emergence of Zika virus (ZIKV) in Brazil and its precipitous expansion throughout the Americas has highlighted the urgent need for a rapid and reliable on-site diagnostic assay suitable for viral detection. Such point-of-need (PON), low-cost diagnostics are essential for ZIKV control in vulnerable areas with limited resources. We developed and evaluated a ZIKV-specific field-deployable RT-iiPCR reagent set targeting the E gene for rapid detection of ZIKV in ZIKV-spiked human and mosquito specimens, and compared its performance to the Center for Disease Control and Prevention (CDC) and Pan American Health Organization (PAHO) RT-qPCR assays targeting the E and NS2B genes, respectively. These assays demonstrated exclusive specificity for ZIKV (African and Asian lineages), had limits of detection ranging from 10 to 100 in vitro transcribed RNA copies/μl and detection endpoints at 10 plaque forming units/ml of infectious tissue culture fluid. Analysis of human whole blood, plasma, serum, semen, urine, and mosquito pool samples spiked with ZIKV showed an agreement of 90% (k = 0.80), 92% (k = 0.82), 95% (k = 0.86), 92% (k = 0.81), 90% (k = 0.79), and 100% (k = 1), respectively, between the RT-iiPCR assay and composite results from the reference RT-qPCR assays. Overall, the concurrence between the ZIKV RT-iiPCR and the reference RT-qPCR assays was 92% (k = 0.83). The ZIKV RT-iiPCR has a performance comparable to the reference CDC and PAHO RT-qPCR assays but provides much faster results (~1.5 h) with a field-deployable system that can be utilized as a PON diagnostic with the potential to significantly improve the quality of the health care system in vulnerable areas.

  18. Influence of degree of deformation in rolling on anneal hardening ...

    Indian Academy of Sciences (India)

    This paper reports results of investigations carried out on a cast copper alloy containing 8 at.% Al. The alloy, and pure copper for the sake of comparison, were subjected to cold rolling with a final reduction of 30, 50 or 70%. The cold rolled copper and copper alloy samples were isochronally and isothermally annealed up to ...

  19. Annealing of silicon optical fibers

    Science.gov (United States)

    Gupta, N.; McMillen, C.; Singh, R.; Podila, R.; Rao, A. M.; Hawkins, T.; Foy, P.; Morris, S.; Rice, R.; Poole, K. F.; Zhu, L.; Ballato, J.

    2011-11-01

    The recent realization of silicon core optical fibers has the potential for novel low insertion loss rack-to-rack optical interconnects and a number of other uses in sensing and biomedical applications. To the best of our knowledge, incoherent light source based rapid photothermal processing (RPP) was used for the first time to anneal glass-clad silicon core optical fibers. X-ray diffraction examination of the silicon core showed a considerable enhancement in the length and amount of single crystallinity post-annealing. Further, shifts in the Raman frequency of the silicon in the optical fiber core that were present in the as-drawn fibers were removed following the RPP treatment. Such results indicate that the RPP treatment increases the local crystallinity and therefore assists in the reduction of the local stresses in the core, leading to more homogenous fibers. The dark current-voltage characteristics of annealed silicon optical fiber diodes showed lower leakage current than the diodes based on as-drawn fibers. Photons in UV and vacuum ultraviolet (VUV) regions play a very important role in improving the bulk and carrier transport properties of RPP-treated silicon optical fibers, and the resultant annealing permits a path forward to in situ enhancement of the structure and properties of these new crystalline core optical fibers.

  20. Development of a Real-Time Fluorescence Loop-Mediated Isothermal Amplification Assay for Rapid and Quantitative Detection of Fusarium oxysporum f. sp. cubense Tropical Race 4 In Soil

    Science.gov (United States)

    Pu, Jinji; Qi, Yanxiang; Yu, Qunfang; Xie, Yixian; Peng, Jun

    2013-01-01

    Fusarium oxysporum f. sp. cubense (Foc), the causal agent of Fusarium wilt (Panama disease), is one of the most devastating diseases of banana (Musa spp.). The Foc tropical race 4 (TR4) is currently known as a major concern in global banana production. No effective resistance is known in Musa to Foc, and no effective measures for controlling Foc once banana plants have been infected in place. Early and accurate detection of Foc TR4 is essential to protect banana industry and guide banana planting. A real-time fluorescence loop-mediated isothermal amplification assay (RealAmp) was developed for the rapid and quantitative detection of Foc TR4 in soil. The detection limit of the RealAmp assay was approximately 0.4 pg/µl plasmid DNA when mixed with extracted soil DNA or 103 spores/g of artificial infested soil, and no cross-reaction with other relative pathogens were observed. The RealAmp assay for quantifying genomic DNA of TR4 was confirmed by testing both artificially and naturally infested samples. Quantification of the soil-borne pathogen DNA of Foc TR4 in naturally infested samples was no significant difference compared to classic real-time PCR (P>0.05). Additionally, RealAmp assay was visual with an improved closed-tube visual detection system by adding SYBR Green I fluorescent dye to the inside of the lid prior to amplification, which avoided the inhibitory effects of the stain on DNA amplification and makes the assay more convenient in the field and could thus become a simple, rapid and effective technique that has potential as an alternative tool for the detection and monitoring of Foc TR4 in field, which would be a routine DNA-based testing service for the soil-borne pathogen in South China. PMID:24376590

  1. Rapid and sensitive detection of novel avian-origin influenza A (H7N9 virus by reverse transcription loop-mediated isothermal amplification combined with a lateral-flow device.

    Directory of Open Access Journals (Sweden)

    Yiyue Ge

    Full Text Available A severe disease in humans caused by a novel avian-origin influenza A (H7N9 virus emerged in China recently, which has caused at least 128 cases and 26 deaths. Rapid detection of the novel H7N9 virus is urgently needed to differentiate the disease from other infections, and to facilitate infection control as well as epidemiologic investigations. In this study, a reverse transcription loop-mediated isothermal amplification combined with a lateral flow device (RT-LAMP-LFD assay to rapidly detect H7N9 virus was developed and evaluated. The RT-LAMP primers were designed to target the haemagglutinin (HA and neuraminidase (NA genes of H7N9 virus. Results of 10-fold dilution series assays showed that analysis of RT-LAMP products by the LFD method was as sensitive as real-time turbidity detection, and that the analytic sensitivities of the HA and NA RT-LAMP assays were both 10 copies of synthetic RNA. Furthermore, both the assays showed 100% clinical specificity for identification of H7N9 virus. The performance characteristics of the RT-LAMP-LFD assay were evaluated with 80 clinical specimens collected from suspected H7N9 patients. The NA RT-LAMP-LFD assay was more sensitive than real time RT-PCR assay. Compared with a combination of virus culture and real-time RT-PCR, the sensitivity, specificity, positive predictive value, and negative predictive value of the RT-LAMP-LFD assay were all 100%. Overall, The RT-LAMP-LFD assay established in this study can be used as a reliable method for early diagnosis of the avian-origin influenza A (H7N9 virus infection.

  2. Isothermal assembly of DNA origami structures using denaturing agents.

    Science.gov (United States)

    Jungmann, Ralf; Liedl, Tim; Sobey, Thomas L; Shih, William; Simmel, Friedrich C

    2008-08-06

    DNA origami is one of the most promising recent developments in DNA self-assembly. It allows for the construction of arbitrary nanoscale patterns and objects by folding a long viral scaffold strand using a large number of short "staple" strands. Assembly is usually accomplished by thermal annealing of the DNA molecules in buffer solution. We here demonstrate that both 2D and 3D origami structures can be assembled isothermally by annealing the DNA strands in denaturing buffer, followed by a controlled reduction of denaturant concentration. This opens up origami assembly for the integration of temperature-sensitive components.

  3. Annealing study of a bistable cluster defect

    Energy Technology Data Exchange (ETDEWEB)

    Junkes, Alexandra, E-mail: alexandra.junkes@desy.d [Institute for Experimental Physics, University of Hamburg, 22761 Hamburg (Germany); Eckstein, Doris [Institute for Experimental Physics, University of Hamburg, 22761 Hamburg (Germany); Pintilie, Ioana [Institute for Experimental Physics, University of Hamburg, 22761 Hamburg (Germany); NIMP Bucharest-Margurele (Romania); Makarenko, Leonid F. [Belarusian State University, Minsk (Belarus); Fretwurst, Eckhart [Institute for Experimental Physics, University of Hamburg, 22761 Hamburg (Germany)

    2010-01-11

    This work deals with the influence of neutron and proton induced cluster related defects on the properties of n-type silicon detectors. Defect concentrations were obtained by means of Deep Level Transient Spectroscopy (DLTS) and Thermally Stimulated Current (TSC) technique, while the full depletion voltage and the reverse current were extracted from capacitance-voltage (C-V) and current-voltage (I-V) characteristics. The annealing behaviour of the reverse current can be correlated with the annealing of the cluster related defect levels labeled E4a and E4b by making use of their bistability. This bistability was characterised by isochronal and isothermal annealing studies and it was found that the development with increasing annealing temperature is similar to that of divacancies. This supports the assumption that E4a and E4b are vacancy related defects. In addition we observe an influence of the disordered regions on the shape and height of the DLTS or TSC signals corresponding to point defects like the vacancy-oxygen complex.

  4. Modelling and multiparameter control applied to a fast annealing furnace; Modelisation et Commande Multivariable Appliquee a un Four de Recuit Rapide

    Energy Technology Data Exchange (ETDEWEB)

    Bardon, B.

    1995-01-31

    Rapid Thermal Processing (RTP) technology is a delicate field to the control engineer. Its compatibility to single-wafer processing is well suited for performing thermal steps in the state-of-the-art integrated circuit (IC) manufacturing. Control of the wafer temperature during the processing is essential. The main problem in the scalar (SISO) approach is due to the steady-state temperature uniformity. A solution to this problem is to vary the spatial energy flux distribution radiating to the wafer. To achieve this requirement, one approach is the use a multivariable (MIMO) control law to manipulate independently the different lamps banks. Thermal process are highly non linear and distributed in nature. Besides, these non-linearities implies process dynamics variations. In this work, after physically describing our process about a reference value of the power and temperature, we present an off-line identification procedure (in the aim of devising a linear multivariable model) using input/output data for different reference values from real experiences and multi-variable least square algorithm. Afterwards, particular attention is devoted to the structure parameter determination of the linear model. Based on the linear model, a multivariable PID controller is designed. The controller coupled with the least mean square identification algorithm is tested under real conditions. The performances of the MIMO adaptive controller is also evaluated in tracking as well as in regulation. (author) refs.

  5. Diagnostic Accuracy of Loop-mediated Isothermal Amplifica-tion Assay as a Field Molecular Tool for Rapid Mass Screening of Old World Leishmania Infections in Sand Flies and In Vitro Culture

    Directory of Open Access Journals (Sweden)

    Mehdi GHODRATI

    2017-12-01

    Full Text Available AbstractBackground: We employed a highly sensitive loop-mediated isothermal amplification (LAMP by targeting 18S rRNA gene to identify the rapid mass screening of Leishmania infections in captured sand flies of southwest Iran and In vitro culture. Methods: One hundred fifty sand flies were collected from 11 sites adjacent to Iraqi’s borders in southern parts of Khuzestan Province by using sticky sheets of paper and CDC miniature light traps during late May 2014 to Nov 2015. Following morphological identification of sand flies species, the DNA of infected samples was extracted and amplified by PCR and LAMP assays by targeting ITS-rDNA and 18S rRNA genes. The PCR amplicons were directly sequenced to conduct the phylogenetic analysis Results: Ten (6.6% Leishmania infections were identified by LAMP assay (detection limit 0.01 parasites DNA among infected Sergentomyia baghdadis, S. sintoni and Phlebotomus papatasi sand flies that was more sensitive than PCR (n=6.4%; (detection limit 101parasites DNA. LAMP can identify 101-106promastigotes/100 µl RPMI 1640 while PCR recognized104-106 promastigotes. The majority infection rate of sand flies was confirmed to L. major inferred by phylogenetic analysis. Conclusion: This is the first exploration characterized the Old World Leishmania infections by LAMP technique in both infected sand flies and In vitro conditions. The LAMP method because of its shorter reaction time, robustness, more sensitivity, lack of requirement of complicated equipment and visual discriminatory of positivity can be appeared a promising tool instead of PCR to identify low Leishmania loads and entomological monitoring of leishmaniasis in resource-limited endemic of the world.

  6. Intravesicle Isothermal DNA Replication

    Directory of Open Access Journals (Sweden)

    Ross Lindsey A

    2011-04-01

    Full Text Available Abstract Background Bacterial and viral DNA replication was previously reconstituted in vitro from component parts 1234. Significant advances in building minimal cell-like structures also have been made recently 567. Combining the two approaches would further attempts to build a minimal cell-like structure capable of undergoing evolution by combining membrane encapsulation and genome replication. Towards this end, we attempted to use purified genomic replication protein components from thermophilic bacterial sources to copy strands of DNA isothermally within lipid vesicles. Findings Bacterial replication components (such as helicases and DNA polymerases are compatible with methods for the generation of lipid vesicles. Encapsulation inside phospholipid vesicles does not inhibit the activity of bacterial DNA genome replication machinery. Further the described system is efficient at isothermally amplifying short segments of DNA within phospholipid vesicles. Conclusions Herein we show that bacterial isothermal DNA replication machinery is functional inside of phospholipid vesicles, suggesting that replicating cellular mimics can be built from purified bacterial components.

  7. Effects of rapid thermal annealing on the properties of HfO{sub 2}/La{sub 2}O{sub 3} nanolaminate films deposited by plasma enhanced atomic layer deposition

    Energy Technology Data Exchange (ETDEWEB)

    Cao, Duo; Cheng, Xinhong, E-mail: xh-cheng@mail.sim.ac.cn; Zheng, Li; Wang, Zhongjian; Xu, Dawei; Xia, Chao; Shen, Lingyan; Wang, Qian; Yu, Yuehui [State Key Laboratory of Functional Materials for Informatics, SIMIT, Chinese Academy of Sciences, Shanghai 200050, People' s Republic of China and University of Chinese Academy of Sciences, Beijing 100049 (China); Shen, DaShen [Department of Electrical and Computer Engineering, University of Alabama in Huntsville, Huntsville, Alabama 35899 (United States)

    2015-01-15

    In this work, HfO{sub 2}/La{sub 2}O{sub 3} nanolaminate films were deposited on Si substrates by plasma enhanced atomic layer deposition with in situ plasma treatment. Different annealing treatments were adopted to change films structure and performance. The upper HfO{sub 2} layers in HfO{sub 2}/La{sub 2}O{sub 3} nanolaminates were easily crystallized after annealing at 800 °C, while all the La{sub 2}O{sub 3} layers kept amorphous. X-ray photoelectron spectroscopy results indicated that LaO(OH) and La(OH){sub 3} peaks became weak, H{sub 2}O molecules in laminates evaporated during high-temperature annealing. Band diagram analysis showed that valence band offset and band gap widened after 800 °C annealing. Annealing, especially 800 °C annealing, had gentle effect on leakage current, but could obviously change capacitance and permittivity due to tetragonal and cubic phase formed in the HfO{sub 2} film.

  8. Optimized Laser Thermal Annealing on Germanium for High Dopant Activation and Low Leakage Current

    DEFF Research Database (Denmark)

    Shayesteh, Maryam; O' Connell, Dan; Gity, Farzan

    2014-01-01

    In this paper, state-of-the-art laser thermal annealing is used to fabricate Ge diodes. We compared the effect of laser thermal annealing (LTA) and rapid thermal annealing (RTA) on dopant activation and electrical properties of phosphorus and Arsenic-doped n +/p junctions. Using LTA, high carrier...

  9. Meat Species Identification using Loop-mediated Isothermal Amplification Assay Targeting Species-specific Mitochondrial DNA.

    Science.gov (United States)

    Cho, Ae-Ri; Dong, Hee-Jin; Cho, Seongbeom

    2014-01-01

    Meat source fraud and adulteration scandals have led to consumer demands for accurate meat identification methods. Nucleotide amplification assays have been proposed as an alternative method to protein-based assays for meat identification. In this study, we designed Loop-mediated isothermal amplification (LAMP) assays targeting species-specific mitochondrial DNA to identify and discriminate eight meat species; cattle, pig, horse, goat, sheep, chicken, duck, and turkey. The LAMP primer sets were designed and the target genes were discriminated according to their unique annealing temperature generated by annealing curve analysis. Their unique annealing temperatures were found to be 85.56±0.07℃ for cattle, 84.96±0.08℃ for pig, and 85.99±0.05℃ for horse in the BSE-LAMP set (Bos taurus, Sus scrofa domesticus and Equus caballus); 84.91±0.11℃ for goat and 83.90±0.11℃ for sheep in the CO-LAMP set (Capra hircus and Ovis aries); and 86.31±0.23℃ for chicken, 88.66±0.12℃ for duck, and 84.49±0.08℃ for turkey in the GAM-LAMP set (Gallus gallus, Anas platyrhynchos and Meleagris gallopavo). No cross-reactivity was observed in each set. The limits of detection (LODs) of the LAMP assays in raw and cooked meat were determined from 10 pg/μL to 100 fg/μL levels, and LODs in raw and cooked meat admixtures were determined from 0.01% to 0.0001% levels. The assays were performed within 30 min and showed greater sensitivity than that of the PCR assays. These novel LAMP assays provide a simple, rapid, accurate, and sensitive technology for discrimination of eight meat species.

  10. Isothermal titration calorimetry.

    Science.gov (United States)

    Lewis, Edwin A; Murphy, Kenneth P

    2005-01-01

    Isothermal titration calorimetry is an ideal technique for measuring biological binding interactions. It does not rely on the presence of chromophores or fluorophores, nor does it require an enzymatic assay. Because the technique relies only on the detection of a heat effect upon binding, it can be used to measure the binding constant, K, the enthalpy of binding, DeltaH degrees and the stoichiometry, or number of binding sites, n. This chapter describes instrumentation, experimental design, and the theoretical underpinnings necessary to run and analyze a calorimetric binding experiment.

  11. Evaluation of loop mediated isothermal amplification for diagnosis of ...

    African Journals Online (AJOL)

    Tuberculosis (TB) remains an important global public health problem. The lack of rapid and accurate diagnostic testing is an important impediment to global tuberculosis control. Loop mediated isothermal amplification (LAMP) is a rapid method for nucleic acid amplification. In this study, we assessed the performance of an ...

  12. Covariant Description of Isothermic Surfaces

    Science.gov (United States)

    Tafel, J.

    2016-12-01

    We present a covariant formulation of the Gauss-Weingarten equations and the Gauss-Mainardi-Codazzi equations for surfaces in 3-dimensional curved spaces. We derive a coordinate invariant condition on the first and second fundamental form which is locally necessary and sufficient for the surface to be isothermic. We show how to construct isothermic coordinates.

  13. Formation of a random recrystallization texture in heavily cold rolled and annealed Al-1%Si alloy

    DEFF Research Database (Denmark)

    Chen, Y.L.; Huang, T.L.; Gong, X.

    2013-01-01

    An Al-1%Si alloy cold rolled to a von Mises stain of 4.5 was isothermally annealed at 210°C. A random recrystallization texture was obtained, which was attributed to the effects of particles of different sizes on the nucleation and growth of grains during recrystallization. © (2013) Trans Tech...

  14. Shock, post-shock annealing, and post-annealing shock in ureilites

    Science.gov (United States)

    Rubin, Alan E.

    2006-01-01

    The thermal and shock histories of ureilites can be divided into four periods: 1) formation, 2) initial shock, 3) post-shock annealing, and 4) post-annealing shock. Period 1 occurred ˜4.55 Ga ago when ureilites formed by melting chondritic material. Impact events during period 2 caused silicate darkening, undulose to mosaic extinction in olivines, and the formation of diamond, lonsdaleite, and chaoite from indigenous carbonaceous material. Alkali-rich fine-grained silicates may have been introduced by impact injection into ureilites during this period. About 57% of the ureilites were unchanged after period 2. During period 3 events, impact-induced annealing caused previously mosaicized olivine grains to become aggregates of small unstrained crystals. Some ureilites experienced reduction as FeO at the edges of olivine grains reacted with C from the matrix. Annealing may also be responsible for coarsening of graphite in a few ureilites, forming euhedral-appearing, idioblastic crystals. Orthopyroxene in Meteorite Hills (MET) 78008 may have formed from pigeonite by annealing during this period. The Rb-Sr internal isochron age of ˜4.0 Ga for MET 78008 probably dates the annealing event. At this late date, impacts are the only viable heat source. About 36% of ureilites experienced period 3 events, but remained unchanged afterwards. During period 4, ˜7% of the ureilites were shocked again, as is evident in the polymict breccia, Elephant Moraine (EET) 83309. This rock contains annealed mosaicized olivine aggregates composed of small individual olivine crystals that exhibit undulose extinction. Ureilites may have formed by impact-melting chondritic material on a primitive body with heterogeneous O isotopes. Plagioclase was preferentially lost from the system due to its low impedance to shock compression. Brief melting and rapid burial minimized the escape of planetary-type noble gases from the ureilitic melts. Incomplete separation of metal from silicates during impact

  15. Sorption isotherm measurements by NMR.

    Science.gov (United States)

    Leisen, Johannes; Beckham, Haskell W; Benham, Michael

    2002-01-01

    An experimental setup is described for the automated recording of sorption isotherms by NMR experiments at precisely defined levels of relative humidity (RH). Implementation is demonstrated for a cotton fabric; Bloch decays. T1 and T2* relaxation times were measured at predefined steps of increasing and decreasing relative humidities (RHs) so that a complete isotherm of NMR properties was obtained. Bloch decays were analyzed by fitting to relaxation functions consisting or a slow- and a fast-relaxing component. The fraction of slow-relaxing component was greater than the fraction of sorbed moisture determined from gravimetric sorption data. The excess slow-relaxing component was attributed to plasticized segments of the formerly rigid cellulose matrix. T1 and T2* sorption isotherms exhibit hysteresis similar to gravimetric sorption isotherms. However, correlating RH to moisture content (MC) reveals that both relaxation constants depend only on MC, and not on the history of moisture exposure.

  16. Hybrid annealing: Coupling a quantum simulator to a classical computer

    Science.gov (United States)

    Graß, Tobias; Lewenstein, Maciej

    2017-05-01

    Finding the global minimum in a rugged potential landscape is a computationally hard task, often equivalent to relevant optimization problems. Annealing strategies, either classical or quantum, explore the configuration space by evolving the system under the influence of thermal or quantum fluctuations. The thermal annealing dynamics can rapidly freeze the system into a low-energy configuration, and it can be simulated well on a classical computer, but it easily gets stuck in local minima. Quantum annealing, on the other hand, can be guaranteed to find the true ground state and can be implemented in modern quantum simulators; however, quantum adiabatic schemes become prohibitively slow in the presence of quasidegeneracies. Here, we propose a strategy which combines ideas from simulated annealing and quantum annealing. In such a hybrid algorithm, the outcome of a quantum simulator is processed on a classical device. While the quantum simulator explores the configuration space by repeatedly applying quantum fluctuations and performing projective measurements, the classical computer evaluates each configuration and enforces a lowering of the energy. We have simulated this algorithm for small instances of the random energy model, showing that it potentially outperforms both simulated thermal annealing and adiabatic quantum annealing. It becomes most efficient for problems involving many quasidegenerate ground states.

  17. Annealing for plant life management: hardness, tensile and Charpy toughness properties of irradiated, annealed and re-irradiated mock-up low alloy nuclear pressure vessel steel

    Energy Technology Data Exchange (ETDEWEB)

    Tipping, Philip; Cripps, Robin (Paul Scherrer Inst. (PSI), Villigen (Switzerland))

    1994-01-01

    Hardness, tensile and Charpy properties of an irradiated (I) and irradiated-annealed-reirradiated (IAR) mock-up pressure vessel steel are presented. Spectrum tailored pressurized light water reactor (PWR) irradiation at 290[sup o]C by fast neutrons up to nominal fluences of 5 x 10[sup 19]/cm[sup 2] (E [>=] 1 MeV) in a swimming pool type reactor caused the hardness, tensile yield stress and tensile strength to increase. Embrittlement also occurred as indicated by Charpy toughness tests. The optimum annealing heat treatment for the main program was determined using isochronal and isothermal runs on the material and measuring the Vickers microhardness. The response to an intermediate annealing treatment (460[sup o]C for 18 h), when 50% of the target fluence has been reached and then irradiating to the required end fluence (IAR condition) was then monitored further by Charpy and tensile mechanical properties. Annealing was beneficial in mitigating overall hardening or embrittlement effects. The rate of re-embrittlement after annealing and re-irradiating was no faster than when no annealing had been performed. Annealing temperatures below 440[sup o]C were indicated as requiring relatively long times, i.e. [>=] 168 h to achieve some reduction in radiation induced hardness for example. (Author).

  18. Radiation annealing in cuprous oxide

    DEFF Research Database (Denmark)

    Vajda, P.

    1966-01-01

    Experimental results from high-intensity gamma-irradiation of cuprous oxide are used to investigate the annealing of defects with increasing radiation dose. The results are analysed on the basis of the Balarin and Hauser (1965) statistical model of radiation annealing, giving a square...

  19. Effective dopant activation by susceptor-assisted microwave annealing of low energy boron implanted and phosphorus implanted silicon

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Zhao; Vemuri, Rajitha N. P.; Alford, T. L., E-mail: TA@asu.edu [School of Matter, Transport, and Energy, Arizona State University, Tempe, Arizona 85287 (United States); David Theodore, N. [CHD-Fab, Freescale Semiconductor Inc., 1300 N. Alma School Rd., Chandler, Arizona 85224 (United States); Lu, Wei; Lau, S. S. [Department of Electrical Engineering, University of California, San Diego, California 92093 (United States); Lanz, A. [Department of Mathematics, Norfolk State University, Norfolk, Virginia 23504 (United States)

    2013-12-28

    Rapid processing and reduced end-of-range diffusion result from susceptor-assisted microwave (MW) annealing, making this technique an efficient processing alternative for electrically activating dopants within ion-implanted semiconductors. Sheet resistance and Hall measurements provide evidence of electrical activation. Susceptor-assisted MW annealing, of ion-implanted Si, enables more effective dopant activation and at lower temperatures than required for rapid thermal annealing (RTA). Raman spectroscopy and ion channeling analyses are used to monitor the extent of ion implantation damage and recrystallization. The presence and behavior of extended defects are monitored by cross-section transmission electron microscopy. Phosphorus implanted Si samples experience effective electrical activation upon MW annealing. On the other hand, when boron implanted Si is MW annealed, the growth of extended defects results in reduced crystalline quality that hinders the electrical activation process. Further comparison of dopant diffusion resulting from MW annealing and rapid thermal annealing is performed using secondary ion mass spectroscopy. MW annealed ion implanted samples show less end-of-range diffusion when compared to RTA samples. In particular, MW annealed P{sup +} implanted samples achieve no visible diffusion and equivalent electrical activation at a lower temperature and with a shorter time-duration of annealing compared to RTA. In this study, the peak temperature attained during annealing does not depend on the dopant species or dose, for susceptor-assisted MW annealing of ion-implanted Si.

  20. Study of a Thermal Annealing Approach for Very High Total Dose Environments

    Science.gov (United States)

    Dhombres, S.; Michez, A.; Boch, J.; Saigné, F.; Beauvivre, S.; Kraehenbuehl, D.; Vaillé, J.-R.; Adell, P. C.; Lorfèvre, E.; Ecoffet, R.; Roig, F.

    2014-12-01

    Total dose effect remains one challenging issue for electronics systems intended to space applications. For high total dose missions, like Jupiter missions, or for scientific instruments for which functionality and precision must be guaranteed, dose effect is one of the main drawbacks. So, new solutions must be found in order to ensure the reliability of the mission. In this paper, an analysis of a thermal annealing approach is done. This approach consists of applying isothermal annealing cycles to a device such that its electrical characteristics can be regenerated after being degraded by total ionizing dose. The analysis is based on experimental results obtained on Power MOSFET and CMOS APS imager. The impact of electric field during annealing is also investigated. It is shown that thermal annealing can be applied to electronic devices in order to extend their lifetime.

  1. Rapid and high-capacity ultrasonic assisted adsorption of ternary toxic anionic dyes onto MOF-5-activated carbon: Artificial neural networks, partial least squares, desirability function and isotherm and kinetic study.

    Science.gov (United States)

    Askari, Hanieh; Ghaedi, Mehrorang; Dashtian, Kheibar; Azghandi, Mohammad Hossein Ahmadi

    2017-07-01

    The present paper focused on the ultrasonic assisted simultaneous removal of fast green (FG), eosin Y (EY) and quinine yellow (QY) from aqueous media following using MOF-5 as a metal organic framework and activated carbon hybrid (AC-MOF-5). The structure and morphology of AC-MOF-5 was identified by SEM, FTIR and XRD analysis. The interactive and main effects of variables such as pH, initial dyes concentration (mgL -1 ), adsorbent dosage (mg) and sonication time (min) on removal percentage were studied by central composite design (CCD), subsequent desirability function (DF) permit to achieved real variable experimental condition. Optimized values were found 7.06, 5.68, 7.59 and 5.04mgL -1 , 0.02g and 2.55min for pH, FG, EY and QY concentration, adsorbent dosage and sonication time, respectively. Under this conditions removal percentage were obtained 98.1%, 98.1% and 91.91% for FG, EY and QY, respectively. Two models, namely partial least squares (PLS) and multi-layer artificial neural network (ANN) model were used for building up to construct an empirical model to predict the dyes under study removal behavior. The obtained results show that ANN and PLS model is a powerful tool for prediction of under-study dyes adsorption by AC-MOF-5. The evaluation and estimation of equilibrium data from traditional isotherm models display that the Langmuir model indicated the best fit to the equilibrium data with maximum adsorption capacity of 21.230, 20.242 and 18.621mgg -1 , for FG, EY and QY, respectively, while the adsorption rate efficiently follows the pseudo-second-order model. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Effect of Annealing Processes on Cu-Zr Alloy Film for Copper Metallization

    Science.gov (United States)

    Wang, Ying; Li, Fu-yin; Tang, Bin-han

    2017-10-01

    The effect of two different annealing processes on the microstructure and barrier-forming ability of Cu-Zr alloy films has been investigated. Cu-Zr alloy films were deposited directly onto SiO2/Si substrates via direct current magnetron sputtering and subsequently annealed by the vacuum annealing process (VAP) or rapid annealing process under argon atmosphere at temperatures 350°C, 450°C, and 550°C. Then, the microstructure, interface characteristics, and electrical properties of the samples were measured. After annealing, the samples showed a preferential (111) crystal orientation, independent of the annealing process. After two annealing methods, Zr aggregated at the Cu-Zr/SiO2 interface and no serious interdiffusion occurred between Cu and Si. The leakage current measurements revealed that the samples annealed by VAP show a higher reliability. According to the results, the vacuum annealing has better barrier performance than the rapid annealing when used for the fabrication of Cu-based interconnects.

  3. Isothermal structural relaxation of Fe40Ni40B20 metallic glass in the relaxation times spectrum model

    NARCIS (Netherlands)

    Csach, K; Haruyama, O; Kasardova, A; Ocelik, Vaclav

    1997-01-01

    The structural relaxation of amorphous as-quenched Fe40Ni40B20 sample was investigated during isothermal annealing at temperatures close to 400 degrees C by: (i) the residual electrical resistance measured at liquid N-2 temperature; (ii) the in-situ electrical resistance; and (iii) the length

  4. Evolution of E-centers during the annealing of Sb-doped Si0.8Ge0.2

    DEFF Research Database (Denmark)

    Kilpeläinen, S.; Tuomisto, F.; Slotte, J.

    2011-01-01

    Evolution of the chemical surroundings of vacancy complexes in Sb-doped ([Sb] = 2 × 1018 and 2 × 1019 cm−3) Si0.8Ge0.2 was studied with positron annihilation spectroscopy in Doppler broadening mode. The study was performed by annealing the samples both isochronally and isothermally. Defect....... The stable state reached after the anneals was found to differ from that measured from an as-grown sample. This difference was deemed to be the result of Ge gathering in small clusters during the annealing thus breaking the initially random Ge distribution....

  5. Laser thermal annealing of Ge, optimized for highly activated dopants and diode ION/IOFF ratios

    DEFF Research Database (Denmark)

    Shayesteh, M.; O'Connell, D.; Gity, F.

    2014-01-01

    The authors compared the influence of laser thermal annealing (LTA) and rapid thermal annealing (RTA) on dopant activation and electrical performance of phosphorus and arsenic doped n+/p junction. High carrier concentration above 1020 cm-3 as well as an ION/IOFF ratio of approximately 105 and ide...

  6. Quantum annealing with manufactured spins.

    Science.gov (United States)

    Johnson, M W; Amin, M H S; Gildert, S; Lanting, T; Hamze, F; Dickson, N; Harris, R; Berkley, A J; Johansson, J; Bunyk, P; Chapple, E M; Enderud, C; Hilton, J P; Karimi, K; Ladizinsky, E; Ladizinsky, N; Oh, T; Perminov, I; Rich, C; Thom, M C; Tolkacheva, E; Truncik, C J S; Uchaikin, S; Wang, J; Wilson, B; Rose, G

    2011-05-12

    Many interesting but practically intractable problems can be reduced to that of finding the ground state of a system of interacting spins; however, finding such a ground state remains computationally difficult. It is believed that the ground state of some naturally occurring spin systems can be effectively attained through a process called quantum annealing. If it could be harnessed, quantum annealing might improve on known methods for solving certain types of problem. However, physical investigation of quantum annealing has been largely confined to microscopic spins in condensed-matter systems. Here we use quantum annealing to find the ground state of an artificial Ising spin system comprising an array of eight superconducting flux quantum bits with programmable spin-spin couplings. We observe a clear signature of quantum annealing, distinguishable from classical thermal annealing through the temperature dependence of the time at which the system dynamics freezes. Our implementation can be configured in situ to realize a wide variety of different spin networks, each of which can be monitored as it moves towards a low-energy configuration. This programmable artificial spin network bridges the gap between the theoretical study of ideal isolated spin networks and the experimental investigation of bulk magnetic samples. Moreover, with an increased number of spins, such a system may provide a practical physical means to implement a quantum algorithm, possibly allowing more-effective approaches to solving certain classes of hard combinatorial optimization problems.

  7. Properties of rapidly solidified Al-12.5 Si-1Ni alloy

    Energy Technology Data Exchange (ETDEWEB)

    Tawtik, N.L.; Abdel Hady, E.M.; Bastawros, A.M. [Nat. Res. Centre, Giza (Egypt). Solid State Phys. Dept.

    1998-11-01

    Rapidly solidified Al-12.5 Si-1 Ni ribbons were prepared by melt spinning. The Si solid solubility was extended to high values as deduced from X-ray diffraction and TEM. This high solubility of Si was found to have significant effects on the various properties of this alloy. High values of electric resistivity was observed which was about four times the fully annealed values. Furthermore rapid solidification improved the tensile strength and the toughness of this alloy as compared with its classically solidified counter part. The relaxation kinetics was followed by isothermal resistivity measurements. The relaxation follows an equation which has the Johnson-Mehl-Avrami (JMA) form. No metastable phase was observed. (orig.)

  8. Isothermal Titration Calorimetry of RNA

    OpenAIRE

    Salim, Nilshad N.; Feig, Andrew L.

    2008-01-01

    Isothermal titration calorimetry (ITC) is a fast and robust method to study the physical basis of molecular interactions. A single well-designed experiment can provide complete thermodynamic characterization of a binding reaction, including Ka, ΔG, ΔH, ΔS and reaction stoichiometry (n). Repeating the experiment at different temperatures allows determination of the heat capacity change (ΔCP) of the interaction. Modern calorimeters are sensitive enough to probe even weak biological interactions...

  9. Study of photoluminescence from annealed bulk-ZnO single crystals

    Energy Technology Data Exchange (ETDEWEB)

    Yoneta, M.; Ohishi, M.; Saito, H. [Department of Applied Physics, Okayama University of Science, 1-1 Ridai-cho, Okayama 700-0005 (Japan); Yoshino, K. [Department of Electrical and Electronic Engineering, Miyazaki University, 1-1 Gakuen Kibanadai-nishi, Miyazaki 889-2192 (Japan); Honda, M. [Faculty of Science, Naruto University of Education, 748 Nakajima, Takashima, Naruto-cho, Naruto-shi 772-8502 (Japan)

    2006-03-15

    We have investigated the influence of rapid thermal annealing on the photoluminescence of bulk-ZnO single crystal. As-grown ZnO wafer, illuminated by 325 nm ultraviolet light at 4.2 K, emitted the visible luminescence of pale green centered of 2.29 eV. The luminescence was observed by the anneal at the temperature range between 400 C and 1000 C, however, its intensity decreased with anneal temperature. The free-exciton and the 2.18 eV emission line were obtained by the anneal at 1200 C for 60 sec. From the X-ray diffraction and the surface morphology measurements, the improvement of the crystallinity of bulk-ZnO crystal were confirmed. We suggest that a rapid thermal annealing technique is convenience to improve the the quality of bul-ZnO single crystals. (copyright 2006 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  10. Detection of fish nocardiosis by loop-mediated isothermal amplification.

    Science.gov (United States)

    Itano, T; Kawakami, H; Kono, T; Sakai, M

    2006-06-01

    Loop-mediated isothermal amplification (LAMP) is a novel method that amplifies DNA with high specificity and rapidity under isothermal conditions. In this study, using the LAMP method, a protocol for detecting Nocardia seriolae which is a causative agent of fish nocardiosis, was designed. A set of four primers, two inner and two outer, were designed based on the sequence of the 16S-23S ribosomal RNA internal transcribed spacer region of N. seriolae. Time and temperature conditions for detection of N. seriolae were optimized for 60 min at 65 degrees C. Other fish pathogen was not amplified by this LAMP system. The detection of N. seriola using LAMP was found to be more sensitive than that by polymerase chain reaction. LAMP is a highly sensitive and rapid diagnostic procedure for detection of N. seriolae. LAMP is a useful diagnostic method for fish nocardiosis.

  11. Error-corrected quantum annealing with hundreds of qubits

    Science.gov (United States)

    Pudenz, Kristen L.; Albash, Tameem; Lidar, Daniel A.

    2014-02-01

    Quantum information processing offers dramatic speedups, yet is susceptible to decoherence, whereby quantum superpositions decay into mutually exclusive classical alternatives, thus robbing quantum computers of their power. This makes the development of quantum error correction an essential aspect of quantum computing. So far, little is known about protection against decoherence for quantum annealing, a computational paradigm aiming to exploit ground-state quantum dynamics to solve optimization problems more rapidly than is possible classically. Here we develop error correction for quantum annealing and experimentally demonstrate it using antiferromagnetic chains with up to 344 superconducting flux qubits in processors that have recently been shown to physically implement programmable quantum annealing. We demonstrate a substantial improvement over the performance of the processors in the absence of error correction. These results pave the way towards large-scale noise-protected adiabatic quantum optimization devices, although a threshold theorem such as has been established in the circuit model of quantum computing remains elusive.

  12. Toward understanding dynamic annealing processes in irradiated ceramics

    Energy Technology Data Exchange (ETDEWEB)

    Myers, Michael Thomas [Texas A & M Univ., College Station, TX (United States)

    2013-05-01

    High energy particle irradiation inevitably generates defects in solids. The ballistic formation and thermalization of the defect creation process occur rapidly, and are believed to be reasonably well understood. However, knowledge of the evolution of defects after damage cascade thermalization, referred to as dynamic annealing, is quite limited. Unraveling the mechanisms associated with dynamic annealing is crucial since such processes play an important role in the formation of stable postirradiation disorder in ion-beam-processing of semiconductors, and determines the “radiation tolerance” of many nuclear materials. The purpose of this dissertation is to further our understanding of the processes involved in dynamic annealing. In order to achieve this, two main tasks are undertaken.

  13. Influence of alloying and secondary annealing on anneal hardening ...

    Indian Academy of Sciences (India)

    Unknown

    Abstract. This paper reports results of investigation carried out on sintered copper alloys (Cu, 8 at%; Zn,. Ni, Al and Cu–Au with 4 at%Au). The alloys were subjected to cold rolling (30, 50 and 70%) and annealed isochronally up to recrystallization temperature. Changes in hardness and electrical conductivity were fol-.

  14. The effect of annealing on the elastoplastic and viscoelastic responses of isotactic polypropylene

    DEFF Research Database (Denmark)

    Drozdov, Aleksey D.; Christiansen, Jesper de Claville

    2002-01-01

    Observations are reported on isotactic polypropylene (i) in a series of tensile tests with a constant strain rate on specimens annealed for 24 h at various temperatures in the range from 110to 150 C, (ii) in two series of creep tests in the subyield region of deformations on samples not subjected...... to thermal treatment and on specimens annealed at 140 C, and (iii) in a series of tensile relaxation tests on non-annealed specimens. Constitutive equations are derived for the elastoplastic and non-linear viscoelastic responses of semicrystalline polymers. A polymer is treated as an equivalent transient...... equations for isothermal deformations with small strains are derived by using the laws of thermodynamics. Adjustable parameters in the stress–strain relations are found by fitting the experimental data. 2003 Elsevier Science B.V. All rights reserved....

  15. Isothermal decomposition kinetics of nickel (II) hydroxide powder

    Energy Technology Data Exchange (ETDEWEB)

    Carney, C.S., E-mail: Casey.Carney@CONTR.NETL.DOE.GOV [National Energy Technology Laboratory, U.S. Dept. of Energy, Albany, OR (United States); AECOM, P.O. Box 1959, Albany, OR (United States); Chinn, R.E.; Doğan, Ö.N. [National Energy Technology Laboratory, U.S. Dept. of Energy, Albany, OR (United States); Gao, M.C. [National Energy Technology Laboratory, U.S. Dept. of Energy, Albany, OR (United States); AECOM, P.O. Box 1959, Albany, OR (United States)

    2015-09-25

    Highlights: • A first order random nucleation model was proposed for the decomposition of nickel hydroxide. • Trapped lattice product water greatly suppressed high conversion reaction rates. • Annealing experiments of the Ni–Ni(OH){sub 2}–NiO phase triangle yielded only two phases: Ni and NiO. • This Ni–Ni(OH){sub 2}–NiO phase triangle in the Ni-rich corner of the Ni–O–H system was confirmed. - Abstract: Nickel (II) hydroxide powder was investigated by thermogravimetry for isothermal decomposition kinetics and verification of the Ni–O–H ternary phase diagram at low temperatures. The activation energy and frequency factor were measured as E{sub a} = 134 kJ/mol and A = 1.27 × 10{sup 10} s{sup −1}, respectively. The validity of the first-order random nucleation model was confirmed, as opposed to diffusion and or moving-boundary models. The dependence of TGA results on specimen size was noted. The Ni–Ni(OH){sub 2}–NiO phase triangle was confirmed. Accordingly, a thermodynamic description of the system was established in the Ni-rich corner, and the isotherm at room temperature is calculated.

  16. Influence of annealing on the shot-peened surface of duplex stainless steel at elevated temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Feng, Qiang; Wu, Xueyan [School of Materials Science and Engineering, Shanghai Jiao Tong University, No. 800 Dongchuan Road, Shanghai 200240 (China); Jiang, Chuanhai, E-mail: chjiang2011@163.com [School of Materials Science and Engineering, Shanghai Jiao Tong University, No. 800 Dongchuan Road, Shanghai 200240 (China); Xu, Zhou; Zhan, Ke [School of Materials Science and Engineering, Shanghai Jiao Tong University, No. 800 Dongchuan Road, Shanghai 200240 (China)

    2013-02-15

    Highlights: ► The relaxations of residual stresses caused by thermal treatments were studied. ► Dislocation density of γ-phase is higher than that of α-phase in the surface after shot peening. ► A new phase appeared apparently at the annealing temperature of 700 °C. ► Activation enthalpy for stress relaxation of γ-phase is lowered than that of α-phase. ► Microhardness is influenced by dislocation density relief and composition of phases. -- Abstract: In order to investigate the residual stress relaxations of shot-peened surface, isothermal annealing treatments were carried out on duplex stainless steel (DSS) S32205 after shot peening (SP) with temperature ranging from 600 to 700 °C. A new phase with a tetragonal crystal structure (σ-phase) appears apparently at the annealing temperature of 700 °C for 64 min. The rates of residual stress relaxation in austenite (γ-phase) are higher than that in ferrite (α-phase) under the corresponding annealing temperature for 64 min. The residual-stress relaxation process during isothermal annealing could be described by Zener–Wert–Avrami function. The activation enthalpy for residual stress relaxation in γ-phase is lower than that in α-phase. At temperature of 700 °C, the microhardness increases gradually after reduction at the initial stage because the strengthening of the new σ-phase is dominating with the prolongation of annealing time, the content-increased γ-phase may also have a certain contribution.

  17. Morphological, thermal and annealed microhardness ...

    Indian Academy of Sciences (India)

    The effects of annealing temperature on the microhardness of IPNs were studied using the Vickers method. SEM indicates the homogeneous morphological features for IPN. The role of gelatin, AN and crosslinker on the developed hard biopolymer has been described with the help of DSC thermograms and microhardness ...

  18. Kinetics of Isothermal Reactive Diffusion Between Solid Cu and Liquid Sn

    Science.gov (United States)

    O, M.; Suzuki, T.; Kajihara, M.

    2017-09-01

    The Cu/Sn system is one of the most fundamental and important metallic systems for solder joints in electric devices. To realize reliable solder joints, information on reactive diffusion at the solder joint is very important. In the present study, we experimentally investigated the kinetics of the reactive diffusion between solid Cu and liquid Sn using semi-infinite Cu/Sn diffusion couples prepared by an isothermal bonding technique. Isothermal annealing of the diffusion couple was conducted in the temperature range of 533-603 K for various times up to 172.8 ks (48 h). Using annealing, an intermetallic layer composed of Cu6Sn5 with scallop morphology and Cu3Sn with rather uniform thickness is formed at the original Cu/Sn interface in the diffusion couple. The growth of the Cu6Sn5 scallop occurs much more quickly than that of the Cu3Sn layer and thus predominates in the overall growth of the intermetallic layer. This tendency becomes more remarkable at lower annealing temperatures. The total thickness of the intermetallic layer is proportional to a power function of the annealing time, and the exponent of the power function is close to unity at all the annealing temperatures. This means that volume diffusion controls the intermetallic growth and the morphology of the Cu6Sn5/Sn interface influences the rate-controlling process. Adopting a mean value of 0.99 for the exponent, we obtain a value of 26 kJ/mol for the activation enthalpy of the intermetallic growth.

  19. Kinetics of Isothermal Reactive Diffusion Between Solid Cu and Liquid Sn

    Science.gov (United States)

    O, M.; Suzuki, T.; Kajihara, M.

    2018-01-01

    The Cu/Sn system is one of the most fundamental and important metallic systems for solder joints in electric devices. To realize reliable solder joints, information on reactive diffusion at the solder joint is very important. In the present study, we experimentally investigated the kinetics of the reactive diffusion between solid Cu and liquid Sn using semi-infinite Cu/Sn diffusion couples prepared by an isothermal bonding technique. Isothermal annealing of the diffusion couple was conducted in the temperature range of 533-603 K for various times up to 172.8 ks (48 h). Using annealing, an intermetallic layer composed of Cu6Sn5 with scallop morphology and Cu3Sn with rather uniform thickness is formed at the original Cu/Sn interface in the diffusion couple. The growth of the Cu6Sn5 scallop occurs much more quickly than that of the Cu3Sn layer and thus predominates in the overall growth of the intermetallic layer. This tendency becomes more remarkable at lower annealing temperatures. The total thickness of the intermetallic layer is proportional to a power function of the annealing time, and the exponent of the power function is close to unity at all the annealing temperatures. This means that volume diffusion controls the intermetallic growth and the morphology of the Cu6Sn5/Sn interface influences the rate-controlling process. Adopting a mean value of 0.99 for the exponent, we obtain a value of 26 kJ/mol for the activation enthalpy of the intermetallic growth.

  20. Quantum Spin Glasses, Annealing and Computation

    Science.gov (United States)

    Tanaka, Shu; Tamura, Ryo; Chakrabarti, Bikas K.

    2017-05-01

    List of tables; List of figures, Preface; 1. Introduction; Part I. Quantum Spin Glass, Annealing and Computation: 2. Classical spin models from ferromagnetic spin systems to spin glasses; 3. Simulated annealing; 4. Quantum spin glass; 5. Quantum dynamics; 6. Quantum annealing; Part II. Additional Notes: 7. Notes on adiabatic quantum computers; 8. Quantum information and quenching dynamics; 9. A brief historical note on the studies of quantum glass, annealing and computation.

  1. Improvement on the electrical characteristics of Pd/HfO{sub 2}/6H-SiC MIS capacitors using post deposition annealing and post metallization annealing

    Energy Technology Data Exchange (ETDEWEB)

    Esakky, Papanasam, E-mail: papanasamte@gmail.com; Kailath, Binsu J

    2017-08-15

    Highlights: • Post deposition annealing (PDA) and post metallization annealing (PMA) on the electrical characteristics of Pd/HfO{sub 2}/6H-SiC MIS capacitors. • Post deposition N{sub 2}O plasma annealing inhibits crystallization of HfO{sub 2} during high temperature annealing. • Plasma annealing followed by RTA in N{sub 2} results in formation of hafnium silicate at the HfO{sub 2}-SiC interface. • PDA reduces interface state density (D{sub it}) and gate leakage current density (J{sub g}) by order. • PMA in forming gas for 40 min results in better passivation and reduces D{sub it} by two orders and J{sub g} by thrice. - Abstract: HfO{sub 2} as a gate dielectric enables high electric field operation of SiC MIS structure and as gas sensor HfO{sub 2}/SiC capacitors offer higher sensitivity than SiO{sub 2}/SiC capacitors. The issue of higher density of oxygen vacancies and associated higher leakage current necessitates better passivation of HfO{sub 2}/SiC interface. Effect of post deposition annealing in N{sub 2}O plasma and post metallization annealing in forming gas on the structural and electrical characteristics of Pd/HfO{sub 2}/SiC MIS capacitors are reported in this work. N{sub 2}O plasma annealing suppresses crystallization during high temperature annealing thereby improving the thermal stability and plasma annealing followed by rapid thermal annealing in N{sub 2} result in formation of Hf silicate at the HfO{sub 2}/SiC interface resulting in order of magnitude lower density of interface states and gate leakage current. Post metallization annealing in forming gas for 40 min reduces interface state density by two orders while gate leakage current density is reduced by thrice. Post deposition annealing in N{sub 2}O plasma and post metallization annealing in forming gas are observed to be effective passivation techniques improving the electrical characteristics of HfO{sub 2}/SiC capacitors.

  2. Isothermal Stability and Selected Mechanical Properties of Zr48Cu36Al8Ag8 Bulk Metallic Glass

    Directory of Open Access Journals (Sweden)

    Błyskun P.

    2017-09-01

    Full Text Available The aim of this work was to investigate the influence of isothermal annealing on the amorphous structure stability of the Zr48Cu36Al8Ag8 alloy. A series of continuous heating examinations was performed on the differential scanning calorimeter in order to determine the temperature limits for isothermal annealing series where the time to crystallization was measured. The obtained results were calculated and a time-temperature-transformation diagram was created and discussed. Static compression test as well as microhardness measurements of the as-quenched samples gave a mechanical properties results supplement. The measured properties (σc = 1800 MPa and 614 HV0.05 are comparable to the literature results for this alloy. Fractographic observations with the scanning electron microscope were also performed in order to prove some plasticity observed during the strength tests.

  3. Isothermal titration calorimetry of RNA.

    Science.gov (United States)

    Salim, Nilshad N; Feig, Andrew L

    2009-03-01

    Isothermal titration calorimetry (ITC) is a fast and robust method to study the physical basis of molecular interactions. A single well-designed experiment can provide complete thermodynamic characterization of a binding reaction, including K(a), DeltaG, DeltaH, DeltaS and reaction stoichiometry (n). Repeating the experiment at different temperatures allows determination of the heat capacity change (DeltaC(P)) of the interaction. Modern calorimeters are sensitive enough to probe even weak biological interactions making ITC a very popular method among biochemists. Although ITC has been applied to protein studies for many years, it is becoming widely applicable in RNA biochemistry as well, especially in studies which involve RNA folding and RNA interactions with small molecules, proteins and with other RNAs. This review focuses on best practices for planning, designing and executing effective ITC experiments when one or more of the reactants is an RNA.

  4. The Insulator to Superconductor Transition in Ga-Doped Semiconductor Ge Single Crystal Induced by the Annealing Temperature

    Directory of Open Access Journals (Sweden)

    Y. B. Sun

    2015-01-01

    Full Text Available We have fabricated the heavily Ga-doped layer in Ge single crystal by the implantation and rapid thermal annealing method. The samples show a crossover from the insulating to the superconducting behavior as the annealing temperature increases. Transport measurements suggest that the superconductivity is from the heavily Ga-doped layer in Ge.

  5. Feasibility of Simulated Annealing Tomography

    CERN Document Server

    Vo, Nghia T; Moser, Herbert O

    2014-01-01

    Simulated annealing tomography (SAT) is a simple iterative image reconstruction technique which can yield a superior reconstruction compared with filtered back-projection (FBP). However, the very high computational cost of iteratively calculating discrete Radon transform (DRT) has limited the feasibility of this technique. In this paper, we propose an approach based on the pre-calculated intersection lengths array (PILA) which helps to remove the step of computing DRT in the simulated annealing procedure and speed up SAT by over 300 times. The enhancement of convergence speed of the reconstruction process using the best of multiple-estimate (BoME) strategy is introduced. The performance of SAT under different conditions and in comparison with other methods is demonstrated by numerical experiments.

  6. Simulated annealing model of acupuncture

    Science.gov (United States)

    Shang, Charles; Szu, Harold

    2015-05-01

    The growth control singularity model suggests that acupuncture points (acupoints) originate from organizers in embryogenesis. Organizers are singular points in growth control. Acupuncture can cause perturbation of a system with effects similar to simulated annealing. In clinical trial, the goal of a treatment is to relieve certain disorder which corresponds to reaching certain local optimum in simulated annealing. The self-organizing effect of the system is limited and related to the person's general health and age. Perturbation at acupoints can lead a stronger local excitation (analogous to higher annealing temperature) compared to perturbation at non-singular points (placebo control points). Such difference diminishes as the number of perturbed points increases due to the wider distribution of the limited self-organizing activity. This model explains the following facts from systematic reviews of acupuncture trials: 1. Properly chosen single acupoint treatment for certain disorder can lead to highly repeatable efficacy above placebo 2. When multiple acupoints are used, the result can be highly repeatable if the patients are relatively healthy and young but are usually mixed if the patients are old, frail and have multiple disorders at the same time as the number of local optima or comorbidities increases. 3. As number of acupoints used increases, the efficacy difference between sham and real acupuncture often diminishes. It predicted that the efficacy of acupuncture is negatively correlated to the disease chronicity, severity and patient's age. This is the first biological - physical model of acupuncture which can predict and guide clinical acupuncture research.

  7. Isothermal thermogravimetric data acquisition analysis system

    Science.gov (United States)

    Cooper, Kenneth, Jr.

    1991-01-01

    The description of an Isothermal Thermogravimetric Analysis (TGA) Data Acquisition System is presented. The system consists of software and hardware to perform a wide variety of TGA experiments. The software is written in ANSI C using Borland's Turbo C++. The hardware consists of a 486/25 MHz machine with a Capital Equipment Corp. IEEE488 interface card. The interface is to a Hewlett Packard 3497A data acquisition system using two analog input cards and a digital actuator card. The system provides for 16 TGA rigs with weight and temperature measurements from each rig. Data collection is conducted in three phases. Acquisition is done at a rapid rate during initial startup, at a slower rate during extended data collection periods, and finally at a fast rate during shutdown. Parameters controlling the rate and duration of each phase are user programmable. Furnace control (raising and lowering) is also programmable. Provision is made for automatic restart in the event of power failure or other abnormal terminations. Initial trial runs were conducted to show system stability.

  8. Competitive annealing of multiple DNA origami: formation of chimeric origami

    Science.gov (United States)

    Majikes, Jacob M.; Nash, Jessica A.; LaBean, Thomas H.

    2016-11-01

    Scaffolded DNA origami are a robust tool for building discrete nanoscale objects at high yield. This strategy ensures, in the design process, that the desired nanostructure is the minimum free energy state for the designed set of DNA sequences. Despite aiming for the minimum free energy structure, the folding process which leads to that conformation is difficult to characterize, although it has been the subject of much research. In order to shed light on the molecular folding pathways, this study intentionally frustrates the folding process of these systems by simultaneously annealing the staple pools for multiple target or parent origami structures, forcing competition. A surprising result of these competitive, simultaneous anneals is the formation of chimeric DNA origami which inherit structural regions from both parent origami. By comparing the regions inherited from the parent origami, relative stability of substructures were compared. This allowed examination of the folding process with typical characterization techniques and materials. Anneal curves were then used as a means to rapidly generate a phase diagram of anticipated behavior as a function of staple excess and parent staple ratio. This initial study shows that competitive anneals provide an exciting way to create diverse new nanostructures and may be used to examine the relative stability of various structural motifs.

  9. A study of the non-isothermal crystallization kinetic of Zn10Se90 glass

    Science.gov (United States)

    Abdel-Rahim, M. A.; Hafiz, M. M.; Abdel-Latief, A. Y.; Abd-Elnaiem, Alaa M.; Alwany, A. Elwhab. B.

    2015-06-01

    The glass transition and the crystallization kinetics of Zn10Se90 glass by differential thermal analysis (DTA) technique under non-isothermal conduction were studied. The effective activation energies of the glass transition and the crystallization have been evaluated on the basses of the Kissinger and Matusita et al. approximations. Kinetic parameters of the crystallization process are significantly influenced by the heating rate. We have compared the experimental DTA with the calculated data curves for Zn10Se90 system using the Johanson-Mehl-Avrami (JMA) and Sestak-Berggren SB( M, N) models. Simulation results indicated that the SB( M, N) model is more suitable for describing the crystallization kinetics for the studied composition. Furthermore, the crystalline phases of annealed Zn10Se90 were characterized by X-ray diffraction. The surface morphology of the annealed samples was examined using scanning electron microscopy.

  10. Microstructure and mechanical behavior of annealed MP35N alloy wire

    Energy Technology Data Exchange (ETDEWEB)

    Prasad, M.J.N.V. [School of Engineering, Brown University, Providence, RI 02912 (United States); Department of Metallurgical Engineering and Materials Science, Indian Institute of Technology Bombay, Powai, Mumbai 400076 (India); Reiterer, M.W. [Medtronic, PLC, USA, Science and Technology, Minneapolis, MN 55432 (United States); Kumar, K.S., E-mail: Sharvan_Kumar@brown.edu [School of Engineering, Brown University, Providence, RI 02912 (United States)

    2015-06-11

    In a previous paper, the microstructure, monotonic, and cyclic response of as-drawn ~100 μm diameter MP35N low-Ti alloy wire were presented and discussed. In this sequel paper, the effects of annealing the same cold-drawn wire on microstructure and mechanical properties are examined. Specifically, segments of the wire were annealed for 1 h at 973 K, 1023 K, 1073 K, 1123 K and 1173 K in a vacuum furnace. The resulting microstructure was characterized by SEM, EBSD and TEM and compared to the as-drawn microstructure. In-situ heating in the TEM of MP35N ribbon in a similarly cold worked condition enabled corroboration of microstructure evolution during annealing. Annealed wires were tested monotonically and cyclically in uniaxial tension at room temperature, the latter using a stress ratio (R) of 0.3. In addition, the annealed wires were tested cyclically at R=−1 using the rotating beam bending fatigue test. Post-deformation structures and fracture surfaces were characterized using TEM and SEM respectively. Annealing the cold drawn wire results in recrystallization and grain growth; the extent is dependent on the annealing temperature. Deformation twin boundaries in the as-drawn structure illustrate faceted bulging and eventually complete elimination, the microstructure evolving into fine equiaxed grains containing coarser annealing twins with no significant change in texture. Yield strength decreases rapidly with recrystallization to almost half the value of the as-drawn condition, but is accompanied by an increase in modulus (by ~25%) and tensile elongation reaching ~30%. Cyclic response by the way of S–N curves is not enhanced by annealing on an absolute stress scale (due to the loss in yield strength) although the annealed wires are cyclically superior when the stress data are normalized by yield stress.

  11. Quantum annealing for combinatorial clustering

    Science.gov (United States)

    Kumar, Vaibhaw; Bass, Gideon; Tomlin, Casey; Dulny, Joseph

    2018-02-01

    Clustering is a powerful machine learning technique that groups "similar" data points based on their characteristics. Many clustering algorithms work by approximating the minimization of an objective function, namely the sum of within-the-cluster distances between points. The straightforward approach involves examining all the possible assignments of points to each of the clusters. This approach guarantees the solution will be a global minimum; however, the number of possible assignments scales quickly with the number of data points and becomes computationally intractable even for very small datasets. In order to circumvent this issue, cost function minima are found using popular local search-based heuristic approaches such as k-means and hierarchical clustering. Due to their greedy nature, such techniques do not guarantee that a global minimum will be found and can lead to sub-optimal clustering assignments. Other classes of global search-based techniques, such as simulated annealing, tabu search, and genetic algorithms, may offer better quality results but can be too time-consuming to implement. In this work, we describe how quantum annealing can be used to carry out clustering. We map the clustering objective to a quadratic binary optimization problem and discuss two clustering algorithms which are then implemented on commercially available quantum annealing hardware, as well as on a purely classical solver "qbsolv." The first algorithm assigns N data points to K clusters, and the second one can be used to perform binary clustering in a hierarchical manner. We present our results in the form of benchmarks against well-known k-means clustering and discuss the advantages and disadvantages of the proposed techniques.

  12. Electromagnetic imaging and simulated annealing

    Science.gov (United States)

    Gibert, Dominique; Virieux, Jean

    1991-05-01

    In contrast with acoustical imaging methods, for which the wave field is dominated by propagation effects, electromagnetic imaging of conductive media suffers from the diffusive behavior of the electromagnetic field. An important question to address when working toward the achievement of electromagnetic imaging concerns the possibility of resolving the diffusion damping. Exact inversion will be looking at the solvability of the integral equation relating a diffusive field to its dual wavefield. This equation is ill posed because its Laplace-like kernel makes the inverse problem of finding the dual wave field a notoriously difficult (both numerically and mathematically) one. Stochastic inversion is another alternative based on least squares fitting. In this inverse problem approach, extracting the wave field is still a relatively instable process, although the L2 misfit function for data without noise presents a global minimum. The simulated annealing overcomes this instability for parameterization of this problem designed as follows. The unknown wave field is expected to be a sequence of impulsive functions. The number of impulsive functions can be determined by using a statistical criterion, called AIC, which comes from the Prony technique. The simulated annealing is applied to the positions of the reflections, while the amplitudes, which are not taken as parameters, are obtained by linear fitting. The simulated annealing method proves to be efficient even in the presence of noise. Furthermore, this nonlinear numerical inversion furnishes statistical quantities which allows an estimation of the resolution. Simple synthetic examples illustrate the performance of the inversion, while a synthetic finite element example shows the final pseudo-seismic section to be processed by standard seismic migration techniques.

  13. Loviisa Unit One: Annealing - healing

    Energy Technology Data Exchange (ETDEWEB)

    Kohopaeae, J.; Virsu, R. [ed.; Henriksson, A. [ed.

    1997-11-01

    Unit 1 of the Loviisa nuclear powerplant was annealed in connection with the refuelling outage in the summer of 1996. This type of heat treatment restored the toughness properties of the pressure vessel weld, which had been embrittled be neutron radiation, so that it is almost equivalent to a new weld. The treatment itself was an ordinary metallurgical procedure that took only a few days. But the material studies that preceded it began over fifteen years ago and have put IVO at the forefront of world-wide expertise in the area of radiation embrittlement

  14. Population Annealing Monte Carlo for Frustrated Systems

    Science.gov (United States)

    Amey, Christopher; Machta, Jonathan

    Population annealing is a sequential Monte Carlo algorithm that efficiently simulates equilibrium systems with rough free energy landscapes such as spin glasses and glassy fluids. A large population of configurations is initially thermalized at high temperature and then cooled to low temperature according to an annealing schedule. The population is kept in thermal equilibrium at every annealing step via resampling configurations according to their Boltzmann weights. Population annealing is comparable to parallel tempering in terms of efficiency, but has several distinct and useful features. In this talk I will give an introduction to population annealing and present recent progress in understanding its equilibration properties and optimizing it for spin glasses. Results from large-scale population annealing simulations for the Ising spin glass in 3D and 4D will be presented. NSF Grant DMR-1507506.

  15. Theory of radiation disordering and annealing semiconductors

    Science.gov (United States)

    Oksengendler, B. L.; Turaeva, N. N.

    A new model of radiation disordering of semiconductors is proposed. According to this model, disordering clusters capable of self-annealing are stabilized by auto-localized electronic excitations (electrons, holes and excitons). Impulse annealing of this medium takes place if the electron stoppers are annihilated so that the disordered clusters emerge. This model is in accordance with experimental data of amorphization and impulse annealing.

  16. Keystream Generator Based On Simulated Annealing

    Directory of Open Access Journals (Sweden)

    Ayad A. Abdulsalam

    2011-01-01

    Full Text Available Advances in the design of keystream generator using heuristic techniques are reported. A simulated annealing algorithm for generating random keystream with large complexity is presented. Simulated annealing technique is adapted to locate these requirements. The definitions for some cryptographic properties are generalized, providing a measure suitable for use as an objective function in a simulated annealing algorithm, seeking randomness that satisfy both correlation immunity and the large linear complexity. Results are presented demonstrating the effectiveness of the method.

  17. Phase Engineering of Perovskite Materials for High-Efficiency Solar Cells: Rapid Conversion of CH3NH3PbI3to Phase-Pure CH3NH3PbCl3via Hydrochloric Acid Vapor Annealing Post-Treatment.

    Science.gov (United States)

    Zhou, Weiran; Zhou, Pengcheng; Lei, Xunyong; Fang, Zhimin; Zhang, Mengmeng; Liu, Qing; Chen, Tao; Zeng, Hualing; Ding, Liming; Zhu, Jun; Dai, Songyuan; Yang, Shangfeng

    2018-01-17

    Organometal halide CH 3 NH 3 PbI 3 (MAPbI 3 ) has been commonly used as the light absorber layer of perovskite solar cells (PSCs), and, especially, another halide element chlorine (Cl) has been often incorporated to assist the crystallization of perovskite film. However, in most cases, a predominant MAPbI 3 phase with trace of Cl - is obtained ultimately and the role of Cl involvement remains unclear. Herein, we develop a low-cost and facile method, named hydrochloric acid vapor annealing (HAVA) post-treatment, and realize a rapid conversion of MAPbI 3 to phase-pure MAPbCl 3 , demonstrating a new concept of phase engineering of perovskite materials toward efficiency enhancement of PSCs for the first time. The average grain size of perovskite film after HAVA post-treatment increases remarkably through an Ostwald ripening process, leading to a denser and smoother perovskite film with reduced trap states and enhanced crystallinity. More importantly, the generation of MAPbCl 3 secondary phase via phase engineering is beneficial for improving the carrier mobility with a more balanced carrier transport rate and enlarging the band gap of perovskite film along with optimized energy level alignment. As a result, under the optimized HAVA post-treatment time (2 min), we achieved a significant enhancement of the power conversion efficiency (PCE) of the MAPbI 3 -based planar heterojunction-PSC device from 14.02 to 17.40% (the highest PCE reaches 18.45%) with greatly suppressed hysteresis of the current-voltage response.

  18. Temperature Scaling Law for Quantum Annealing Optimizers.

    Science.gov (United States)

    Albash, Tameem; Martin-Mayor, Victor; Hen, Itay

    2017-09-15

    Physical implementations of quantum annealing unavoidably operate at finite temperatures. We point to a fundamental limitation of fixed finite temperature quantum annealers that prevents them from functioning as competitive scalable optimizers and show that to serve as optimizers annealer temperatures must be appropriately scaled down with problem size. We derive a temperature scaling law dictating that temperature must drop at the very least in a logarithmic manner but also possibly as a power law with problem size. We corroborate our results by experiment and simulations and discuss the implications of these to practical annealers.

  19. Magnetic and mechanical properties of Cu (75 wt%) – 316L grade stainless steels synthesized by ball milling and annealing

    Energy Technology Data Exchange (ETDEWEB)

    Mondal, Bholanath, E-mail: bholanath_mondal@yahoo.co.in [Department of Central Scientific Services, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700032 (India); Chabri, Sumit [Department of Metallurgy and Materials Engineering, Indian Institute of Engineering Science and Technology, Shibpur, Howrah 711103 (India); Sardar, Gargi [Department of Zoology, Baruipur College, South 24 Parganas, 743610 (India); Bhowmik, Nandagopal [Department of Metallurgy and Materials Engineering, Indian Institute of Engineering Science and Technology, Shibpur, Howrah 711103 (India); Sinha, Arijit, E-mail: arijitsinha2@yahoo.co.in [School of Materials Science and Engineering, Indian Institute of Engineering Science and Technology, Shibpur, Howrah 711103 (India); Chattopadhyay, Partha Protim [Department of Metallurgy and Materials Engineering, Indian Institute of Engineering Science and Technology, Shibpur, Howrah 711103 (India)

    2015-05-01

    Elemental powders of Cu (75 wt%) and 316-stainless steel (25 wt%) has been subjected to ball milling upto 70 h followed by isothermal annealing at the temperature range of 350–750 °C for 1 h to investigate the microstructural evolution along with magnetic and mechanical properties. After 40 h of milling, the bcc Fe is almost dissolved in the solid solution of Cu but no significant change has been observed in the XRD pattern after 70 h of milling, Annealing of the alloy has resulted in precipitation of nanocrystalline bcc-Fe in Cu which triggers the soft ferromagnetic properties. The extensive mechanical characterization has been done at the microstructural scale by nanoindentation technique which demonstrates a hardening behavior of the compacted and annealed alloys due to possible precipitation of nanocrystalline bcc-Fe in Cu. - Highlights: • Nanocrystalline phases with partial amorphorization obtained after 70 h of milling. • Precipitation and grain coarsening of Fe and Cu after annealing as observed by XRD. • Annealing of the ball milled sample upto 550 {sup o}C has evolved ferromagnetic behavior. • Nanoindentation predicts a hardening behavior of annealed ball milled samples.

  20. DOE`s annealing prototype demonstration projects

    Energy Technology Data Exchange (ETDEWEB)

    Warren, J.; Nakos, J.; Rochau, G.

    1997-02-01

    One of the challenges U.S. utilities face in addressing technical issues associated with the aging of nuclear power plants is the long-term effect of plant operation on reactor pressure vessels (RPVs). As a nuclear plant operates, its RPV is exposed to neutrons. For certain plants, this neutron exposure can cause embrittlement of some of the RPV welds which can shorten the useful life of the RPV. This RPV embrittlement issue has the potential to affect the continued operation of a number of operating U.S. pressurized water reactor (PWR) plants. However, RPV material properties affected by long-term irradiation are recoverable through a thermal annealing treatment of the RPV. Although a dozen Russian-designed RPVs and several U.S. military vessels have been successfully annealed, U.S. utilities have stated that a successful annealing demonstration of a U.S. RPV is a prerequisite for annealing a licensed U.S. nuclear power plant. In May 1995, the Department of Energy`s Sandia National Laboratories awarded two cost-shared contracts to evaluate the feasibility of annealing U.S. licensed plants by conducting an anneal of an installed RPV using two different heating technologies. The contracts were awarded to the American Society of Mechanical Engineers (ASME) Center for Research and Technology Development (CRTD) and MPR Associates (MPR). The ASME team completed its annealing prototype demonstration in July 1996, using an indirect gas furnace at the uncompleted Public Service of Indiana`s Marble Hill nuclear power plant. The MPR team`s annealing prototype demonstration was scheduled to be completed in early 1997, using a direct heat electrical furnace at the uncompleted Consumers Power Company`s nuclear power plant at Midland, Michigan. This paper describes the Department`s annealing prototype demonstration goals and objectives; the tasks, deliverables, and results to date for each annealing prototype demonstration; and the remaining annealing technology challenges.

  1. GPU accelerated population annealing algorithm

    Science.gov (United States)

    Barash, Lev Yu.; Weigel, Martin; Borovský, Michal; Janke, Wolfhard; Shchur, Lev N.

    2017-11-01

    Population annealing is a promising recent approach for Monte Carlo simulations in statistical physics, in particular for the simulation of systems with complex free-energy landscapes. It is a hybrid method, combining importance sampling through Markov chains with elements of sequential Monte Carlo in the form of population control. While it appears to provide algorithmic capabilities for the simulation of such systems that are roughly comparable to those of more established approaches such as parallel tempering, it is intrinsically much more suitable for massively parallel computing. Here, we tap into this structural advantage and present a highly optimized implementation of the population annealing algorithm on GPUs that promises speed-ups of several orders of magnitude as compared to a serial implementation on CPUs. While the sample code is for simulations of the 2D ferromagnetic Ising model, it should be easily adapted for simulations of other spin models, including disordered systems. Our code includes implementations of some advanced algorithmic features that have only recently been suggested, namely the automatic adaptation of temperature steps and a multi-histogram analysis of the data at different temperatures. Program Files doi:http://dx.doi.org/10.17632/sgzt4b7b3m.1 Licensing provisions: Creative Commons Attribution license (CC BY 4.0) Programming language: C, CUDA External routines/libraries: NVIDIA CUDA Toolkit 6.5 or newer Nature of problem: The program calculates the internal energy, specific heat, several magnetization moments, entropy and free energy of the 2D Ising model on square lattices of edge length L with periodic boundary conditions as a function of inverse temperature β. Solution method: The code uses population annealing, a hybrid method combining Markov chain updates with population control. The code is implemented for NVIDIA GPUs using the CUDA language and employs advanced techniques such as multi-spin coding, adaptive temperature

  2. Kinetics of Ferrite Recrystallization and Austenite Formation During Intercritical Annealing of the Cold-Rolled Ferrite/Martensite Duplex Structures

    Science.gov (United States)

    Mazaheri, Y.; Kermanpur, A.; Najafizadeh, A.; Kalashami, A. Ghatei

    2016-03-01

    Ultrafine-grained, dual-phase (UFG DP) steels were produced by a new route using an uncommon cold-rolling and subsequent intercritical annealing of ferrite/martensite duplex starting microstructures. The effects of processing parameters such as rolling reduction, intercritical annealing temperature, and time on the microstructural evaluations have been studied. UFG DP steels with an average grain size of about 1 to 2 μm were achieved by short intercritical annealing of the 80 pct cold-rolled duplex microstructures. The kinetics of ferrite recrystallization and austenite formation were studied based on the Johnson-Mehl-Avrami-Kolmogorov (JMAK) model. The proposed model for describing the isothermal austenite formation kinetics was applied successfully to the nonisothermal conditions. It was found that complete recrystallization of ferrite before the austenite formation led to the formation of a large extent randomly distributed austenite in the ferrite matrix and a chain-networked structure.

  3. Nanocomposite Nd-Fe-Ti-B magnets produced by melt spinning and flash annealing

    Science.gov (United States)

    Hosokawa, Akihide; Takagi, Kenta; Kuriiwa, Takahiro

    2017-10-01

    We have attempted to fabricate a nanocomposite Nd-Fe-Ti-B magnet. Flash-lamp rapid annealing treatments were performed for melt-spun ribbons to obtain the α-Fe/Nd2Fe14B composite microstructure, and the evolution of magnetic properties by the annealing was studied by vibration sample magnetometer (VSM). It was found that the magnetic properties were improved by relatively short-time annealing at the temperatures near the crystallization temperature. Further higher-temperature and longer annealing treatments resulted in deterioration of the magnetic properties. For the selected samples, recoil curves were measured to analyze the spring-back behaviors. Transmission electron microscopy (TEM) was performed to investigate the microstructural factors for the deterioration of the magnetic properties. The relation between the variation of the magnetic properties (coercivity, saturation magnetization and recoil permeability) and the microstructural factors were discussed.

  4. Atomic-scale investigation of graphene grown on Cu foil and the effects of thermal annealing.

    Science.gov (United States)

    Cho, Jongweon; Gao, Li; Tian, Jifa; Cao, Helin; Wu, Wei; Yu, Qingkai; Yitamben, Esmeralda N; Fisher, Brandon; Guest, Jeffrey R; Chen, Yong P; Guisinger, Nathan P

    2011-05-24

    We have investigated the effects of thermal annealing on ex-situ chemically vapor deposited submonolayer graphene islands on polycrystalline Cu foil at the atomic-scale using ultrahigh vacuum scanning tunneling microscopy. Low-temperature annealed graphene islands on Cu foil (at ∼430 °C) exhibit predominantly striped Moiré patterns, indicating a relatively weak interaction between graphene and the underlying polycrystalline Cu foil. Rapid high-temperature annealing of the sample (at 700-800 °C) gives rise to the removal of Cu oxide and the recovery of crystallographic features of the copper that surrounds the intact graphene. These experimental observations of continuous crystalline features between the underlying copper (beneath the graphene islands) and the surrounding exposed copper areas revealed by high-temperature annealing demonstrates the impenetrable nature of graphene and its potential application as a protective layer against corrosion.

  5. The effect of annealing on the nonlinear viscoelastic response of isotactic polypropylene

    DEFF Research Database (Denmark)

    Drozdov, Aleksey D.; Christiansen, Jesper de Claville

    2002-01-01

    Three series of tensile relaxation tests are performed on isotactic polypropylene at room temperature in the vicinity of the yield point. In the first series of experiments, injection-molded samples are used without thermal pre-treatment. In the second and third series. the specimens are annealed...... at 130°C for 4 and 24 hours, respectively. Constitutive equations are derived for the time-dependent response of semicrystalline polymers at isothermal loading with small strains. A polymer is treated as an equivalent temporary network of macromolecules bridged by junctions (physical cross...... spectrum (characterized by the distribution of MRs with various potential energies) is independent of mechanical factors, but is altered at annealing. For specimens not subjected to thermal treatment, the growth of longitudinal strain does not affect the volume fraction of active MRs and the attempt rate...

  6. Lattice location of platinum ions implanted into single crystal zirconia and their annealing behaviour

    Energy Technology Data Exchange (ETDEWEB)

    Cao, D.X. [Royal Melbourne Inst. of Tech., VIC (Australia); Sood, D.K. [Academia Sinica, Shanghai, SH (China). Shanghai Inst. of Nuclear Research; Brown, I.G. [Lawrence Berkeley Lab., CA (United States)

    1993-12-31

    Single crystal samples of (100) oriented cubic zirconia stabilised with 9.5 mol % yttria were implanted with platinum ions, using a metal vapour vacuum arc (MEVVA) high current ion implanter, to a nominal dose of 1x10{sup 17} ions/cm{sup 2}. The implanted samples were annealed isothermally in air ambient at 1200 deg C, from 1-24 hours. Rutherford Backscattering Spectrometry and Channeling (RBSC) of 2 MeV He ions are employed to determine depth distributions of ion damage, Pt ions and substitutionality of Pt ions before and after annealing. The damage behaviour, Pt migration and lattice location are discussed in terms of metastable phase formation and solid solubility considerations. 7 refs., 3 figs.

  7. Nitrogen Adsorption on Graphene Sponges Synthesized by Annealing a Mixture of Nickel and Carbon Powders

    Directory of Open Access Journals (Sweden)

    Grehov V.

    2017-08-01

    Full Text Available Adsorption by graphene sponge (GS manufactured by annealing nickel-carbon powder mixture in inert atmosphere has been studied. By determining the specific surface area (SSA for the GS sample, it has been found that Brunauer, Emmett, Teller method (BET of approximation of experimental isotherms gives wrong results in the pressure range of 0.025–0.12 because adsorption in this pressure region is affected by walls of ampoule. Real SSA value has been found by subtracting pore effect method (SPE or by BET approximation in a low range of relative pressure of 0.0004–0.002.

  8. Influence of Intercritical Annealing Temperature on Mechanical ...

    African Journals Online (AJOL)

    The influence of intercritical annealing temperature on the microstructure and mechanical properties of an 0.23%C low alloy steel was undertaken in this work. The as-received steel was normalised and afterwards annealed in the (α+γ) region at 730OC, 750OC, 770OC and 790OC followed by quenching in hot water at ...

  9. Isothermal and Two-Temperature Zone Selenization of Mo Layers

    Directory of Open Access Journals (Sweden)

    L. Kaupmees

    2012-01-01

    Full Text Available Glass/Mo, Mo foil, glass/Mo/In, and glass/Mo/Cu stacked layers were selenized in closed vacuum tubes by isothermal and/or two-temperature zone annealing in Se vapors. The selenization process was studied dependent on Se vapor pressure, temperature and time. Samples were selenized from 375 to 580°C for 30 and 60 minutes. The applied Se pressure was varied between 130 and 4.4⋅103 Pa. The increase of MoSe2 film thickness was found to depend on the origin of Mo. MoSe2 thickness dL on Mo-foil was much higher than on sputtered Mo layers, and it depended linearly on time and as a power function dL~PSe1/2 on Se vapor pressure. The residual oxygen content in the formed MoSe2 layers was much lower in the two-zone selenization process. If Mo was covered with Cu or In before selenization, these were found to diffuse into formed MoSe2 layer. All the MoSe2 layers showed p-type conductivity.

  10. Visual Detection of Potato leafroll virus by One-step Reverse Transcription Loop-Mediated Isothermal Amplification of DNA with Hydroxynaphthol Blue Dye

    NARCIS (Netherlands)

    Ahmadi, S.; Almasi, A.M.; Fatehi, F.; Struik, P.C.; Moradi, A.

    2013-01-01

    Loop-mediated isothermal amplification (LAMP) assay is a novel technique for amplifying DNA under constant temperature, with high specificity, sensitivity, rapidity and efficiency. We applied reverse transcription loop-mediated isothermal amplification (RT-LAMP) to visually detect Potato leafroll

  11. Isothermal and non-isothermal torrefaction characteristics and kinetics of microalga Scenedesmus obliquus CNW-N.

    Science.gov (United States)

    Chen, Wei-Hsin; Wu, Zih-Ying; Chang, Jo-Shu

    2014-03-01

    Isothermal and non-isothermal torrefaction characteristics and kinetics of microalga Scenedesmus obliquus (S. obliquus) CNW-N are studied using thermogravimetric analysis. The pyrolysis of S. obliquus CNW-N with increasing temperature is characterized by four-stage decomposition. Depending on the torrefaction temperature, light, mild, and severe torrefaction from the weight loss and the maximum decomposition rate of the microalga can be classified. Under the same average temperature and torrefaction duration, non-isothermal torrefaction gives more severe pretreatment than the isothermal one. Increasing the heating rate of non-isothermal torrefaction also intensifies the pretreatment severity. Therefore, microalgae can be torrefied via non-isothermal torrefaction in a shorter time under the same pretreatment extent. The atomic H/C ratio in the microalga decreases with increasing torrefaction severity, whereas the atomic O/C ratio rises. The analysis suggests that the activation energy of isothermal torrefaction is 57.52×10(3)Jmol(-1), while it is between 40.14×10(3) and 88.41×10(3)Jmol(-1) for non-isothermal torrefaction. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. Modeling of Experimental Adsorption Isotherm Data

    Directory of Open Access Journals (Sweden)

    Xunjun Chen

    2015-01-01

    Full Text Available Adsorption is considered to be one of the most effective technologies widely used in global environmental protection areas. Modeling of experimental adsorption isotherm data is an essential way for predicting the mechanisms of adsorption, which will lead to an improvement in the area of adsorption science. In this paper, we employed three isotherm models, namely: Langmuir, Freundlich, and Dubinin-Radushkevich to correlate four sets of experimental adsorption isotherm data, which were obtained by batch tests in lab. The linearized and non-linearized isotherm models were compared and discussed. In order to determine the best fit isotherm model, the correlation coefficient (r2 and standard errors (S.E. for each parameter were used to evaluate the data. The modeling results showed that non-linear Langmuir model could fit the data better than others, with relatively higher r2 values and smaller S.E. The linear Langmuir model had the highest value of r2, however, the maximum adsorption capacities estimated from linear Langmuir model were deviated from the experimental data.

  13. Influence of the microstructure on the magnetic properties of Fe{sub 86}Zr{sub 7}Nb{sub 1}Cu{sub 1}B{sub 5} alloy in the states following solidification and following short-duration annealing below the crystallization temperature

    Energy Technology Data Exchange (ETDEWEB)

    Gondro, Joanna, E-mail: j.gondro@wp.pl

    2017-06-15

    Highlights: • The samples prepared, in the form of ribbons, using a rapid-cooling method. • Amorphous ribbon of the alloy, of nominal composition Fe{sub 86}Zr{sub 7}Nb{sub 1}Cu{sub 1}B{sub 5}. • The amorphous structure was confirmed using XRD, Mössbauer spectroscopy and the microstructure of the specimens were observed with the use of high resolution transmission electron microscopy. • The magnetic properties of the samples were determined by analysis of initial magnetization curves. - Abstract: This paper investigates the influence of heat treatment on the magnetic properties of alloy samples prepared, in the form of ribbons, using a rapid-cooling method. The adopted isothermal annealing processes were found to lead: to the homogenization of the composition, to relaxation of the structure in the amorphous state, and to nanocrystallization. It has been shown that structural relaxation, occurring within the volume of the tested samples, exerts a large influence on the magnetic properties. Observed changes in the distribution of the induction hyperfine field at the {sup 57}Fe nuclei represent direct proof that chemical and topological disorder exists within the volume of the alloy, and the annealing process reduces the internal energy of the entire system. Considering the random anisotropy model for nanocrystalline materials, it can be concluded that the factor that increases, for example, the saturation magnetization is an increase in strength of exchange interactions, which is a measure of the ferromagnetic correlation interactions.

  14. Precision Laser Annealing of Focal Plane Arrays

    Energy Technology Data Exchange (ETDEWEB)

    Bender, Daniel A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); DeRose, Christopher [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Starbuck, Andrew Lea [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Verley, Jason C. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Jenkins, Mark W. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-09-01

    We present results from laser annealing experiments in Si using a passively Q-switched Nd:YAG microlaser. Exposure with laser at fluence values above the damage threshold of commercially available photodiodes results in electrical damage (as measured by an increase in photodiode dark current). We show that increasing the laser fluence to values in excess of the damage threshold can result in annealing of a damage site and a reduction in detector dark current by as much as 100x in some cases. A still further increase in fluence results in irreparable damage. Thus we demonstrate the presence of a laser annealing window over which performance of damaged detectors can be at least partially reconstituted. Moreover dark current reduction is observed over the entire operating range of the diode indicating that device performance has been improved for all values of reverse bias voltage. Additionally, we will present results of laser annealing in Si waveguides. By exposing a small (<10 um) length of a Si waveguide to an annealing laser pulse, the longitudinal phase of light acquired in propagating through the waveguide can be modified with high precision, <15 milliradian per laser pulse. Phase tuning by 180 degrees is exhibited with multiple exposures to one arm of a Mach-Zehnder interferometer at fluence values below the morphological damage threshold of an etched Si waveguide. No reduction in optical transmission at 1550 nm was found after 220 annealing laser shots. Modeling results for laser annealing in Si are also presented.

  15. Applicability of Different Isothermal EOS at Nanomaterials

    Directory of Open Access Journals (Sweden)

    Deepika P. Joshi

    2013-01-01

    Full Text Available The present study explains the behaviour of nanomaterials such as AlN, CdSe, Ge, WC, and Ni- and Fe-filled-MWCNTs under high pressure. Among the number of isothermal EOSs available, we prefer only two parameter-based isothermal equations (i.e., Murnaghan equation, usual Tait's equation, Suzuki equation and Shanker equation. The present work shows the theoretical study of thermo-elastic properties especially relative compression (V/V0, isothermal bulk modulus (KP/K0, and compressibility (αP/α0 of nanomaterials. After comparing all formulations with available experimental data, we conclude that pressure dependence of relative compression (V/V0 for the nanomaterials, are in good agreement for all the equations at lower pressure range. At higher pressure range, Suzuki and Shanker formulations show some deviation from experimental values.

  16. Cylinder packing by simulated annealing

    Directory of Open Access Journals (Sweden)

    M. Helena Correia

    2000-12-01

    Full Text Available This paper is motivated by the problem of loading identical items of circular base (tubes, rolls, ... into a rectangular base (the pallet. For practical reasons, all the loaded items are considered to have the same height. The resolution of this problem consists in determining the positioning pattern of the circular bases of the items on the rectangular pallet, while maximizing the number of items. This pattern will be repeated for each layer stacked on the pallet. Two algorithms based on the meta-heuristic Simulated Annealing have been developed and implemented. The tuning of these algorithms parameters implied running intensive tests in order to improve its efficiency. The algorithms developed were easily extended to the case of non-identical circles.Este artigo aborda o problema de posicionamento de objetos de base circular (tubos, rolos, ... sobre uma base retangular de maiores dimensões. Por razões práticas, considera-se que todos os objetos a carregar apresentam a mesma altura. A resolução do problema consiste na determinação do padrão de posicionamento das bases circulares dos referidos objetos sobre a base de forma retangular, tendo como objetivo a maximização do número de objetos estritamente posicionados no interior dessa base. Este padrão de posicionamento será repetido em cada uma das camadas a carregar sobre a base retangular. Apresentam-se dois algoritmos para a resolução do problema. Estes algoritmos baseiam-se numa meta-heurística, Simulated Annealling, cuja afinação de parâmetros requereu a execução de testes intensivos com o objetivo de atingir um elevado grau de eficiência no seu desempenho. As características dos algoritmos implementados permitiram que a sua extensão à consideração de círculos com raios diferentes fosse facilmente conseguida.

  17. GIBBS ADSORPTION ISOTHERM FOR CONCENTRATION AS VARIABLE

    OpenAIRE

    SHIMIN ZHANG

    2005-01-01

    Gibbs adsorption isotherm of the multicomponent system for concentration instead of chemical potential as independent variables is deduced and explained in a simple way. For the multicomponent system composed of α and β phases with plane interface, if the β phase is a dilute solution, and component k is solvent as well as $c_k^\\alpha \\ll c_k^\\beta, c_i^\\alpha \\ll c_i^\\beta$, Gibbs adsorption isotherm of component i can be expressed as $\\Gamma_i^{(k)} = -(c_i^\\beta/RT)(\\partial \\gamma/\\partial...

  18. Simultaneous elimination of carryover contamination and detection of DNA with uracil-DNA-glycosylase-supplemented loop-mediated isothermal amplification (UDG-LAMP).

    Science.gov (United States)

    Hsieh, Kuangwen; Mage, Peter L; Csordas, Andrew T; Eisenstein, Michael; Soh, H Tom

    2014-04-11

    We report a one-pot, closed-vessel enzymatic assay that eliminates carryover contamination while preserving robust DNA amplification in loop-mediated isothermal amplification (LAMP), providing reliable and rapid detection of target DNA in contaminated samples.

  19. Global warming: Temperature estimation in annealers

    Directory of Open Access Journals (Sweden)

    Jack Raymond

    2016-11-01

    Full Text Available Sampling from a Boltzmann distribution is NP-hard and so requires heuristic approaches. Quantum annealing is one promising candidate. The failure of annealing dynamics to equilibrate on practical time scales is a well understood limitation, but does not always prevent a heuristically useful distribution from being generated. In this paper we evaluate several methods for determining a useful operational temperature range for annealers. We show that, even where distributions deviate from the Boltzmann distribution due to ergodicity breaking, these estimates can be useful. We introduce the concepts of local and global temperatures that are captured by different estimation methods. We argue that for practical application it often makes sense to analyze annealers that are subject to post-processing in order to isolate the macroscopic distribution deviations that are a practical barrier to their application.

  20. Gradient Solvent Vapor Annealing of Thin Films

    Science.gov (United States)

    Albert, Julie; Bogart, Timothy; Lewis, Ronald; Epps, Thomas

    2011-03-01

    The development of block copolymer materials for emerging nanotechnologies requires an understanding of how surface energy/chemistry and annealing conditions affect thin film self-assembly. Specifically, in solvent vapor annealing (SVA), the use of solvent mixtures and the manipulation of solvent vapor concentration are promising approaches for obtaining a desired morphology or nanostructure orientation. We designed and fabricated solvent-resistant devices to produce discrete SVA gradients in composition and/or concentration to efficiently explore SVA parameter space. We annealed copolymer films containing poly(styrene), poly(isoprene), and/or poly(methyl methacrylate) blocks, monitored film thicknesses during annealing, and characterized film morphologies with atomic force microscopy. Morphological changes across the gradients such as the transformation from parallel cylinders to spheres with increasing solvent selectivity provided insight into thin film self-assembly, and the gradient device has enabled us to determine transition compositions and/or concentrations.

  1. Sequence crystallization during isotherm evaporation of southern ...

    African Journals Online (AJOL)

    Sequence crystallization during isotherm evaporation of southern Algeria chott Baghdad natural brine. M Zatout, M Hacini, A.H. Hamzaoui, A M'nif. Abstract. Southern Algerian's natural brine sampled from chott Baghdad may be a source of mineral salts with a high economic value. These salts are recoverable by simple ...

  2. LIMEPY: Lowered Isothermal Model Explorer in PYthon

    Science.gov (United States)

    Gieles, Mark; Zocchi, Alice

    2017-10-01

    LIMEPY solves distribution function (DF) based lowered isothermal models. It solves Poisson's equation used on input parameters and offers fast solutions for isotropic/anisotropic, single/multi-mass models, normalized DF values, density and velocity moments, projected properties, and generates discrete samples.

  3. LNA-modified isothermal oligonucleotide microarray for ...

    Indian Academy of Sciences (India)

    Experimental results revealed that KOD Dash DNA polymerase could efficiently incorporate Cy3-dCTP into the PCR products, and the LNA-isothermal ... Key Laboratory of Medical Cell Biology (Ministry of Education), Department of Biochemistry and Molecular Biology, China Medical University, Shenyang, 110001, China ...

  4. Performance Characteristics of an Isothermal Freeze Valve

    Energy Technology Data Exchange (ETDEWEB)

    Hailey, A.E.

    2001-08-22

    This document discusses performance characteristics of an isothermal freeze valve. A freeze valve has been specified for draining the DWPF melter at the end of its lifetime. Two freeze valve designs have been evaluated on the Small Cylindrical Melter-2 (SCM-2). In order to size the DWPF freeze valve, the basic principles governing freeze valve behavior need to be identified and understood.

  5. Isothermal Titration Calorimetry in the Student Laboratory

    Science.gov (United States)

    Wadso, Lars; Li, Yujing; Li, Xi

    2011-01-01

    Isothermal titration calorimetry (ITC) is the measurement of the heat produced by the stepwise addition of one substance to another. It is a common experimental technique, for example, in pharmaceutical science, to measure equilibrium constants and reaction enthalpies. We describe a stirring device and an injection pump that can be used with a…

  6. High Temperature Annealing Studies on the Piezoelectric Properties of Thin Aluminum Nitride Films

    Energy Technology Data Exchange (ETDEWEB)

    R. Farrell; V. R. Pagan; A. Kabulski; Sridhar Kuchibhatl; J. Harman; K. R. Kasarla; L. E. Rodak; P. Famouri; J. Peter Hensel; D. Korakakis

    2008-05-01

    A Rapid Thermal Annealing (RTA) system was used to anneal sputtered and MOVPE grown Aluminum Nitride (AlN) thin films at temperatures up to 1000°C in ambient and controlled environments. According to Energy Dispersive X-Ray Analysis (EDAX), the films annealed in an ambient environment rapidly oxidize after five minutes at 1000°C. Below 1000°C the films oxidized linearly as a function of annealing temperature which is consistent with what has been reported in literature [1]. Laser Doppler Vibrometry (LDV) was used to measure the piezoelectric coefficient, d33, of these films. Films annealed in an ambient environment had a weak piezoelectric response indicating that oxidation on the surface of the film reduces the value of d33. A high temperature furnace has been built that is capable of taking in-situ measurements of the piezoelectric response of AlN films. In-situ d33 measurements are recorded up to 300°C for both sputtered and MOVPE-grown AlN thin films. The measured piezoelectric response appears to increase with temperature up to 300°C possibly due to stress in the film.

  7. High Temperature Annealing Studies on the Piezoelectric Properties of Thin Aluminum Nitride Films

    Energy Technology Data Exchange (ETDEWEB)

    Farrell, R.; Pagan, V.R.; Kabulski, A.; Kuchibhatla, S.; Harman, J.; Kasarla, K.R.; Rodak, L.E.; Hensel, J.P.; Famouri, P.; Korakakis, D.

    2008-01-01

    A Rapid Thermal Annealing (RTA) system was used to anneal sputtered and MOVPE-grown Aluminum Nitride (AlN) thin films at temperatures up to 1000°C in ambient and controlled environments. According to Energy Dispersive X-Ray Analysis (EDAX), the films annealed in an ambient environment rapidly oxidize after five minutes at 1000°C. Below 1000°C the films oxidized linearly as a function of annealing temperature which is consistent with what has been reported in literature [1]. Laser Doppler Vibrometry (LDV) was used to measure the piezoelectric coefficient, d33, of these films. Films annealed in an ambient environment had a weak piezoelectric response indicating that oxidation on the surface of the film reduces the value of d33. A high temperature furnace has been built that is capable of taking in-situ measurements of the piezoelectric response of AlN films. In-situ d33 measurements are recorded up to 300°C for both sputtered and MOVPE-grown AlN thin films. The measured piezoelectric response appears to increase with temperature up to 300°C possibly due to stress in the film.

  8. Structural relaxation in annealed hyperquenched basaltic glasses

    DEFF Research Database (Denmark)

    Guo, Xiaoju; Mauro, John C.; Potuzak, M.

    2012-01-01

    The enthalpy relaxation behavior of hyperquenched (HQ) and annealed hyperquenched (AHQ) basaltic glass is investigated through calorimetric measurements. The results reveal a common onset temperature of the glass transition for all the HQ and AHQ glasses under study, indicating that the primary...... relaxation is activated at the same temperature regardless of the initial departure from equilibrium. The analysis of secondary relaxation at different annealing temperatures provides insights into the enthalpy recovery of HQ glasses....

  9. Microfluidic continuous flow digital loop-mediated isothermal amplification (LAMP).

    Science.gov (United States)

    Rane, Tushar D; Chen, Liben; Zec, Helena C; Wang, Tza-Huei

    2015-02-07

    Digital nucleic acid detection is rapidly becoming a popular technique for ultra-sensitive and quantitative detection of nucleic acid molecules in a wide range of biomedical studies. Digital polymerase chain reaction (PCR) remains the most popular way of conducting digital nucleic acid detection. However, due to the need for thermocycling, digital PCR is difficult to implement in a streamlined manner on a single microfluidic device, leading to complex fragmented workflows and multiple separate devices and instruments. Loop-mediated isothermal amplification (LAMP) is an excellent isothermal alternative to PCR with potentially better specificity than PCR because of the use of multiple primer sets for a nucleic acid target. Here we report a microfluidic droplet device implementing all the steps required for digital nucleic acid detection including droplet generation, incubation and in-line detection for digital LAMP. As compared to microchamber or droplet array-based digital assays, the continuous flow operation of this device eliminates the constraints on the number of total reactions imposed by the footprint of the device and the analysis throughput caused by the time for lengthy incubation and transfer of materials between instruments.

  10. Robust isothermal electric control of exchange bias at room temperature

    Science.gov (United States)

    Binek, Christian

    2011-03-01

    Voltage-controlled spintronics is of particular importance to continue progress in information technology through reduced power consumption, enhanced processing speed, integration density, and functionality in comparison with present day CMOS electronics. Almost all existing and prototypical solid-state spintronic devices rely on tailored interface magnetism, enabling spin-selective transmission or scattering of electrons. Controlling magnetism at thin-film interfaces, preferably by purely electrical means, is a key challenge to better spintronics. Currently, most attempts to electrically control magnetism focus on potentially large magnetoelectric effects of multiferroics. We report on our interest in magnetoelectric Cr 2 O3 (chromia). Robust isothermal electric control of exchange bias is achieved at room temperature in perpendicular anisotropic Cr 2 O3 (0001)/CoPd exchange bias heterostructures. This discovery promises significant implications for potential spintronics. From the perspective of basic science, our finding serves as macroscopic evidence for roughness-insensitive and electrically controllable equilibrium boundary magnetization in magnetoelectric antiferromagnets. The latter evolves at chromia (0001) surfaces and interfaces when chromia is in one of its two degenerate antiferromagnetic single domain states selected via magnetoelectric annealing. Theoretical insight into the boundary magnetization and its role in electrically controlled exchange bias is gained from first-principles calculations and general symmetry arguments. Measurements of spin-resolved ultraviolet photoemission, magnetometry at Cr 2 O3 (0001) surfaces, and detailed investigations of the unique exchange bias properties of Cr 2 O3 (0001)/CoPd including its electric controllability provide macroscopically averaged information about the boundary magnetization of chromia. Laterally resolved X-ray PEEM and temperature dependent MFM reveal detailed microscopic information of the chromia

  11. Coronal Loops: Evolving Beyond the Isothermal Approximation

    Science.gov (United States)

    Schmelz, J. T.; Cirtain, J. W.; Allen, J. D.

    2002-05-01

    Are coronal loops isothermal? A controversy over this question has arisen recently because different investigators using different techniques have obtained very different answers. Analysis of SOHO-EIT and TRACE data using narrowband filter ratios to obtain temperature maps has produced several key publications that suggest that coronal loops may be isothermal. We have constructed a multi-thermal distribution for several pixels along a relatively isolated coronal loop on the southwest limb of the solar disk using spectral line data from SOHO-CDS taken on 1998 Apr 20. These distributions are clearly inconsistent with isothermal plasma along either the line of sight or the length of the loop, and suggested rather that the temperature increases from the footpoints to the loop top. We speculated originally that these differences could be attributed to pixel size -- CDS pixels are larger, and more `contaminating' material would be expected along the line of sight. To test this idea, we used CDS iron line ratios from our data set to mimic the isothermal results from the narrowband filter instruments. These ratios indicated that the temperature gradient along the loop was flat, despite the fact that a more complete analysis of the same data showed this result to be false! The CDS pixel size was not the cause of the discrepancy; rather, the problem lies with the isothermal approximation used in EIT and TRACE analysis. These results should serve as a strong warning to anyone using this simplistic method to obtain temperature. This warning is echoed on the EIT web page: ``Danger! Enter at your own risk!'' In other words, values for temperature may be found, but they may have nothing to do with physical reality. Solar physics research at the University of Memphis is supported by NASA grant NAG5-9783. This research was funded in part by the NASA/TRACE MODA grant for Montana State University.

  12. Effects of annealing conditions on the dielectric properties of solution-processed Al2O3 layers for indium-zinc-tin-oxide thin-film transistors.

    Science.gov (United States)

    Kim, Yong-Hoon; Kim, Kwang-Ho; Park, Sung Kyu

    2013-11-01

    In this paper, the effects of annealing conditions on the dielectric properties of solution-processed aluminum oxide (Al2O3) layers for indium-zinc-tin-oxide (IZTO) thin-film transistors (TFTs) have been investigated. The dielectric properties of Al2O3 layers such as leakage current density and dielectric strength were largely affected by their annealing conditions. In particular, oxygen partial pressure in rapid thermal annealing, and the temperature profile of hot plate annealing had profound effects on the dielectric properties. From a refractive index analysis, the enhanced dielectric properties of Al2O3 gate dielectrics can be attributed to higher film density depending on the annealing conditions. With the low-temperature-annealed Al2O3 gate dielectric at 350 degrees C, solution-processed IZTO TFTs with a field-effect mobility of approximately 2.2 cm2/Vs were successfully fabricated.

  13. Pyrolysis kinetics of coking coal mixed with biomass under non-isothermal and isothermal conditions.

    Science.gov (United States)

    Jeong, Ha Myung; Seo, Myung Won; Jeong, Sang Mun; Na, Byung Ki; Yoon, Sang Jun; Lee, Jae Goo; Lee, Woon Jae

    2014-03-01

    To investigate the kinetic characteristics of coking coal mixed with biomass during pyrolysis, thermogravimetric (TG) and thermo-balance reactor (TBR) analyses were conducted under non-isothermal and isothermal condition. Yellow poplar as a biomass (B) was mixed with weak coking coal (WC) and hard coking coal (HC), respectively. The calculated activation energies of WC/B blends were higher than those of HC/B blends under non-isothermal and isothermal conditions. The coal/biomass blends show increased reactivity and decreased activation energy with increasing biomass blend ratio, regardless of the coking properties of the coal. The different char structures of the WC/B and HC/B blends were analyzed by BET and SEM. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Detection of Botrytis cinerea by loop-mediated isothermal amplification.

    Science.gov (United States)

    Tomlinson, J A; Dickinson, M J; Boonham, N

    2010-12-01

    To develop a sensitive, rapid and simple method for detection of Botrytis cinerea based on loop-mediated isothermal amplification (LAMP) that would be suitable for use outside a conventional laboratory setting. A LAMP assay was designed based on the intergenic spacer of the B. cinerea nuclear ribosomal DNA (rDNA). The resulting assay was characterized in terms of sensitivity and specificity using DNA extracted from cultures. The assay consistently amplified 65 pg B. cinerea DNA. No cross-reactivity was observed with a range of other fungal pathogens, with the exception of the closely related species Botrytis pelargonii. Use of a novel real-time LAMP platform (the OptiGene Genie I) allowed detection of B. cinerea in infected rose petals, with amplification occurring in cut flowers, fruit and vegetables. © 2010 British Crown Copyright. Letters in Applied Microbiology 51, 650-657 © 2010 The Society for Applied Microbiology.

  15. Isothermal Aging Precipitate of TB17 Titanium Alloy

    Directory of Open Access Journals (Sweden)

    WANG Zhe

    2016-10-01

    Full Text Available Transmission Electron Microscope (TEM, X-Ray Diffraction(XRD and Optical Microscope(OMwere employed to investigate the aging precipitation behavior of a new type of ultra-high strength TB17 titanium alloy. The results show that during heat solution treated in the β phase field followed by aging the secondary α phase is nucleated, precipitated and grew on the β phase matrix,and the precipitated phase is lamellar structure which has burgers relation with the matrix. The secondary α phase content is increased rapidly and finally reach a steady-state as aging time increased and the final product of aging consists of α phase and β phase. there is a good linearity relationship between the content of secondary α phase and the hardness of age hardening. The TB17 titanium alloy isothermal phase transformation kinetics can be described by JMAK equation.

  16. Origin of reverse annealing effect in hydrogen-implanted silicon

    Energy Technology Data Exchange (ETDEWEB)

    Di, Zengfeng [Los Alamos National Laboratory; Nastasi, Michael A [Los Alamos National Laboratory; Wang, Yongqiang [Los Alamos National Laboratory

    2009-01-01

    In contradiction to conventional damage annealing, thermally annealed H-implanted Si exhibits an increase in damage or reverse annealing behavior, whose mechanism has remained elusive. On the basis of quantitative high resolution transmission electron microscopy combined with channeling Rutherford backscattering analysis, we conclusively elucidate that the reverse annealing effect is due to the nucleation and growth of hydrogen-induce platelets. Platelets are responsible for an increase in the height and width the channeling damage peak following increased isochronal anneals.

  17. Quantum Annealing and Quantum Fluctuation Effect in Frustrated Ising Systems

    OpenAIRE

    Tanaka, Shu; Tamura, Ryo

    2012-01-01

    Quantum annealing method has been widely attracted attention in statistical physics and information science since it is expected to be a powerful method to obtain the best solution of optimization problem as well as simulated annealing. The quantum annealing method was incubated in quantum statistical physics. This is an alternative method of the simulated annealing which is well-adopted for many optimization problems. In the simulated annealing, we obtain a solution of optimization problem b...

  18. Investigations on variation of defects in fused silica with different annealing atmospheres using positron annihilation spectroscopy

    Science.gov (United States)

    Zhang, Lijuan; Chen, Jing; Jiang, Yilan; Liu, Jiandang; Gu, Bingchuan; Jiang, Xiaolong; Bai, Yang; Zhang, Chuanchao; Wang, Haijun; Luan, Xiaoyu; Ye, Bangjiao; Yuan, Xiaodong; Liao, Wei

    2017-10-01

    The laser damage resistance properties of the fused silica can be influenced by the microstructure variation of the atom-size intrinsic defects and voids in bulk silica. Two positron annihilation spectroscopy techniques have been used to investigate the microstructure variation of the vacancy clusters and the structure voids in the polishing redeposition layer and the defect layer of fused silica after annealing in different atmospheres. The fused silica samples were isothermally annealed at 1000 K for 3 h in a furnace under an air atmosphere, a vacuum atmosphere and a hydrogen atmosphere, respectively. The positron annihilation results show that ambient oxygen atmosphere only affects the surface of the fused silica (about 300 nm depth) due to the large volume and low diffusion coefficient of the oxygen atom. However, hydrogen atoms can penetrate into the defect layer inside the fused silica and then have an influence on vacancy defects and vacancy clusters, while having no effect on the large voids. Besides, research results indicate that an annealing process can reduce the size and concentration of vacancy clusters. The obtained data can provide important information for understanding the laser damage mechanism and improving laser damage resistance properties of the fused silica optics.

  19. Isothermal calorimetry on enzymatic biodiesel production

    DEFF Research Database (Denmark)

    Fjerbæk, Lene

    2008-01-01

    information about effects taking place when using lipases immobilized on an inert carrier for transesterification of a triglyceride and an alcohol as for biodiesel production. The biodiesel is produced by rapeseed oil and methanol as well as ethanol and a commercial biocatalyst Novozym 435 from Novozymes...... containing a Candida Antarctica B lipase immobilized on an acrylic resin. The reaction investigated is characterized by immiscible liquids (oil, methanol, glycerol and biodiesel) and enzymes imm. on an inert carrier during reaction, which allows several effects to take place that during normal reaction...... conditions can not be elucidated. These effects have been observed with isothermal calorimetry bringing forth new information about the reaction of enzymes catalyzing transesterification. Enzymatic biodiesel production has until now not been investigated with isothermal microcalorimetry, but the results...

  20. Analysis of Cooperativity by Isothermal Titration Calorimetry

    Directory of Open Access Journals (Sweden)

    Alan Brown

    2009-08-01

    Full Text Available Cooperative binding pervades Nature. This review discusses the use of isothermal titration calorimetry (ITC in the identification and characterisation of cooperativity in biological interactions. ITC has broad scope in the analysis of cooperativity as it determines binding stiochiometries, affinities and thermodynamic parameters, including enthalpy and entropy in a single experiment. Examples from the literature are used to demonstrate the applicability of ITC in the characterisation of cooperative systems.

  1. Analysis of cooperativity by isothermal titration calorimetry.

    Science.gov (United States)

    Brown, Alan

    2009-08-04

    Cooperative binding pervades Nature. This review discusses the use of isothermal titration calorimetry (ITC) in the identification and characterisation of cooperativity in biological interactions. ITC has broad scope in the analysis of cooperativity as it determines binding stiochiometries, affinities and thermodynamic parameters, including enthalpy and entropy in a single experiment. Examples from the literature are used to demonstrate the applicability of ITC in the characterisation of cooperative systems.

  2. Analysis of Cooperativity by Isothermal Titration Calorimetry

    OpenAIRE

    Brown, Alan

    2009-01-01

    Cooperative binding pervades Nature. This review discusses the use of isothermal titration calorimetry (ITC) in the identification and characterisation of cooperativity in biological interactions. ITC has broad scope in the analysis of cooperativity as it determines binding stiochiometries, affinities and thermodynamic parameters, including enthalpy and entropy in a single experiment. Examples from the literature are used to demonstrate the applicability of ITC in the characterisation of coop...

  3. Sorption isotherms of Portuguese varieties of pears.

    OpenAIRE

    Barroca, Maria João

    2005-01-01

    In this study the desorption isotherms of fresh pears were investigated at 30 ºC for fruits of the varieties Amêndoa, Amorim, Carapinheira Branca and S. Bartolomeu, all original from Portugal. This value of temperature was established to represent the summer average daily temperatures in Portugal, where the solar dried of pears is carried out. From the results obtained it was possible to verify that the behaviour of the equilibrium moisture content against the corresponding water activity is ...

  4. Adsorption isotherms of pear at several temperatures

    Directory of Open Access Journals (Sweden)

    Mitrevski Vangelče

    2015-01-01

    Full Text Available The moisture adsorption isotherms of pear were determined at 15ºC, 30ºC and 45ºC using the standard static gravimetric method over a range of water activity from 0.112 to 0.920. The experimental data were fitted with isotherm equations recommended in ASAE Standard D245.5. In order to find which equation gives the best results, large number of numerical experiments were performed. After that, several statistical criteria proposed in scientific literature for estimation and selection of the best sorption isotherm equations were used. For each equation and experimental data set, the average performance index was calculated and models were ranked afterwards. After that, some statistical rejection criteria were checked (D’Agostino-Pearson test of normality, single-sample run test and significance and precision of the model parameters. The performed statistical analysis shows that the Guggenheim-Anderson-de Boer (GAB equation has the highest value of average performance index, but higher correlation between pair of parameters leads to lower precision of estimated parameters.[Projekat Ministarstva nauke Republike Srbije, br. TR 31058

  5. Annealing recovery of nanoscale silicon surface damage caused by Ga focused ion beam

    Energy Technology Data Exchange (ETDEWEB)

    Xiao, Y.J.; Fang, F.Z., E-mail: fzfang@gmail.com; Xu, Z.W., E-mail: zongweixu@163.com; Hu, X.T.

    2015-07-15

    Graphical abstract: - Highlights: • The defects growth increased rapidly at low dose, and then significantly slowed down before continued amorphous layer formed. • The swelling of implantation region results from the combination of surface roughing and the decrease in the surface density. • Both melting on the top surface and recrystallization at crystalline/amorphous interface have existed as annealing at 2400 K, which is near the melting point. • Ga ions migrated together and were swept by the c-Si/a-Si interface during annealing, left sunken at the surface. - Abstracts: In this paper, molecular dynamics method with the Tersoff–ZBL combined interatomic potential was adopted to study the dynamics of focused ion beam (FIB) milling and subsequent annealing. The Ga FIB induced damage and its recovery mechanism during subsequent annealing process were investigated in nanoscale time and space. To investigate the nanoscale damage during FIB milling with the ion energy of 0.5 keV, 1 keV and 2 keV, radial distribution function, bond length distribution, bond angle distribution, and common neighbour analysis (CNA) were calculated and analyzed under various ion doses. FIB irradiated silicon substrate with ion dose of 2 × 10{sup 14} ions/cm{sup 2} was annealed at various annealing temperatures from 1400 K to 2400 K. Molecular dynamics simulation illustrated that as a-Si region was surrounded by c-Si after implantation, the recrystallization lead to a c-Si regrowth processes both from bottom towards top surface and from periphery to centre. The damage area profiles by CNA represented a shortest recovery time of 2.0 ns at 2200 K. Both melting on the top surface and recrystallization at crystalline/amorphous interface have existed as annealing at 2400 K, which is near the melting point. Ga migrated together and moved towards the surface with the a-Si/c-Si interface.

  6. Hydrogen Annealing Of Single-Crystal Superalloys

    Science.gov (United States)

    Smialek, James L.; Schaeffer, John C.; Murphy, Wendy

    1995-01-01

    Annealing at temperature equal to or greater than 2,200 degrees F in atmosphere of hydrogen found to increase ability of single-crystal superalloys to resist oxidation when subsequently exposed to oxidizing atmospheres at temperatures almost as high. Supperalloys in question are principal constituents of hot-stage airfoils (blades) in aircraft and ground-based turbine engines; also used in other high-temperature applications like chemical-processing plants, coal-gasification plants, petrochemical refineries, and boilers. Hydrogen anneal provides resistance to oxidation without decreasing fatigue strength and without need for coating or reactive sulfur-gettering constituents. In comparison with coating, hydrogen annealing costs less. Benefits extend to stainless steels, nickel/chromium, and nickel-base alloys, subject to same scale-adhesion and oxidation-resistance considerations, except that scale is chromia instead of alumina.

  7. Traffic Flow Optimization Using a Quantum Annealer

    Directory of Open Access Journals (Sweden)

    Florian Neukart

    2017-12-01

    Full Text Available Quantum annealing algorithms belong to the class of metaheuristic tools, applicable for solving binary optimization problems. Hardware implementations of quantum annealing, such as the quantum processing units (QPUs produced by D-Wave Systems, have been subject to multiple analyses in research, with the aim of characterizing the technology’s usefulness for optimization and sampling tasks. In this paper, we present a real-world application that uses quantum technologies. Specifically, we show how to map certain parts of a real-world traffic flow optimization problem to be suitable for quantum annealing. We show that time-critical optimization tasks, such as continuous redistribution of position data for cars in dense road networks, are suitable candidates for quantum computing. Due to the limited size and connectivity of current-generation D-Wave QPUs, we use a hybrid quantum and classical approach to solve the traffic flow problem.

  8. Impact of laser anneal on NiPt silicide texture and chemical composition

    Energy Technology Data Exchange (ETDEWEB)

    Feautrier, C.; Ozcan, A. S.; Lavoie, C.; Valery, A.; Beneyton, R.; Borowiak, C.; Clément, L.; Pofelski, A.; Salem, B.

    2017-06-14

    We have combined synchrotron X-ray pole figure measurements and transmission electron microscopy (TEM) nano-beam diffraction to study the impact of millisecond laser anneal on the texture and microstructure of NiPt silicide thin films. The powerful use of nano-beam diffraction in plan-view geometry allows here for both a mapping of grain orientation and intra-grain measurements even if these crystalline grains become very small. With this unique combination of local and large-scale probes, we find that silicide formation on n and p doped substrates using laser annealing results in smaller grains compared with the films processed using standard rapid thermal annealing. The laser annealed samples also result in grains that are more epitaxially oriented with respect to the Si substrate. For n-type substrate, the film is dominated by (020) and (013) oriented fibers with significant levels of intra-grain bending (transrotation) observed in both types of grains. For p-type substrates, mostly epitaxially aligned grains are detected. TEM coupled with energy-dispersive X-ray analysis was also used to study the elemental distribution in the silicide samples. Here, we confirm that laser anneal leads to a larger accumulation of platinum at the silicide-substrate interface and modifies the distribution of dopants throughout the film.

  9. Annealing effects and DLTS study on NPN silicon bipolar junction transistors irradiated by heavy ions

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Chaoming; Li, Xingji, E-mail: lxj0218@hit.edu.cn; Yang, Jianqun; Rui, Erming

    2014-01-21

    Isochronal anneal sequences have been carried out on 3DG112 silicon NPN bipolar junction transistors (BJTs) irradiated with 20 MeV bromine (Br) heavy ions. The Gummel curve is utilized to characterize the annealing behavior of defects in both the emitter-base depletion region and the neutral base. We find that the base current (I{sub B}) decreases with the increasing annealing temperature, while the collector current (I{sub C}) remains invariable. The current gain varies slightly, when the annealing temperature (T{sub A}) is lower than 400 K, while varies rapidly at T{sub A}<450 K, and the current gain of the 3DG112 BJT annealing at 700 K almost restore to that of the pre-radiation transistor. Deep level transient spectroscopy (DLTS) data is used to assign the relative magnitude of each of the important defects. Based on the in situ electrical measurement and DLTS spectra, it is clear that the V{sub 2}(−/0)+V-P traps are the main contribution to the degradation of current gain after the 20 MeV Br ions irradiation. The V{sub 2}(−/0)+V-P peak has many of the characteristics expected for the current gain degradation.

  10. Annealing effects and DLTS study on NPN silicon bipolar junction transistors irradiated by heavy ions

    Science.gov (United States)

    Liu, Chaoming; Li, Xingji; Yang, Jianqun; Rui, Erming

    2014-01-01

    Isochronal anneal sequences have been carried out on 3DG112 silicon NPN bipolar junction transistors (BJTs) irradiated with 20 MeV bromine (Br) heavy ions. The Gummel curve is utilized to characterize the annealing behavior of defects in both the emitter-base depletion region and the neutral base. We find that the base current (IB) decreases with the increasing annealing temperature, while the collector current (IC) remains invariable. The current gain varies slightly, when the annealing temperature (TA) is lower than 400 K, while varies rapidly at TABJT annealing at 700 K almost restore to that of the pre-radiation transistor. Deep level transient spectroscopy (DLTS) data is used to assign the relative magnitude of each of the important defects. Based on the in situ electrical measurement and DLTS spectra, it is clear that the V2(-/0)+V-P traps are the main contribution to the degradation of current gain after the 20 MeV Br ions irradiation. The V2(-/0)+V-P peak has many of the characteristics expected for the current gain degradation.

  11. Sequential multiple-step europium ion implantation and annealing of GaN

    KAUST Repository

    Miranda, S. M C

    2014-01-20

    Sequential multiple Eu ion implantations at low fluence (1×1013 cm-2 at 300 keV) and subsequent rapid thermal annealing (RTA) steps (30 s at 1000 °C or 1100 °C) were performed on high quality nominally undoped GaN films grown by metal organic chemical vapour deposition (MOCVD) and medium quality GaN:Mg grown by hydride vapour phase epitaxy (HVPE). Compared to samples implanted in a single step, multiple implantation/annealing shows only marginal structural improvement for the MOCVD samples, but a significant improvement of crystal quality and optical activation of Eu was achieved in the HVPE films. This improvement is attributed to the lower crystalline quality of the starting material, which probably enhances the diffusion of defects and acts to facilitate the annealing of implantation damage and the effective incorporation of the Eu ions in the crystal structure. Optical activation of Eu3+ ions in the HVPE samples was further improved by high temperature and high pressure annealing (HTHP) up to 1400 °C. After HTHP annealing the main room temperature cathodo- and photoluminescence line in Mg-doped samples lies at ∼ 619 nm, characteristic of a known Mg-related Eu3+ centre, while after RTA treatment the dominant line lies at ∼ 622 nm, typical for undoped GaN:Eu. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Positron annihilation spectroscopy study on annealing effect of CuO nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Shi, Jianjian; Wang, Jiaheng; Yang, Wei; Zhu, Zhejie; Wu, Yichu, E-mail: ycwu@whu.edu.cn [School of Physics and Technology, Hubei Key Laboratory of Nuclear Solid State Physics, Wuhan University (WHU), Wuhan (China)

    2016-03-15

    The microstructure and defects of CuO nanoparticles under isochronal annealing were investigated by positron annihilation spectroscopy (PAS), X-ray diffraction (XRD) and scanning electron microscope (SEM). XRD and SEM results indicated that the average grain sizes of CuO nanoparticles grew slowly below 800 °C, and then increased rapidly with the annealing temperature from 800 to 1000 °C. Positron lifetime analysis exhibited that positrons were mainly annihilated in mono-vacancies (V{sub Cu}, V{sub O}) and vacancy clusters when annealing from 200 to 800 °C. Furthermore, W-S plot of Doppler broadening spectra at different annealing temperatures found that the (W, S) points distributed on two different defect species, which suggested that V{sup −}{sub Cu} - V{sup +}{sub O} complexes were produced when the grains grew to bigger size after annealing above 800 °C, and positrons might annihilate at these complexes. (author)

  13. Adsorption isotherm of non-azeotropic solution onto porous adsorbents

    Science.gov (United States)

    Bono, A.; Ramlan, N. A.; Anisuzzaman, S. M.; Chu, C. M.; Farm, Y. Y.

    2016-06-01

    Adsorption isotherm is essential component in the understanding of the adsorption process. Several methods of the measurements, analysis and interpretation of adsorption from solution have been reported in the literature. Most of the measurements of adsorption isotherm from solution were involved the measurement of excess isotherm conducted at low region of sorbates concentration. Direct interpretation of excess adsorption isotherm as adsorption isotherm is always been practice. Therefore, in this work a study on the measurement of the adsorption isotherm from solution of non-azeotropic organic solvent mixture onto porous adsorbents for whole range of liquid concentration was conducted. The study included the measurement of excess adsorption isotherm using conventional technique. Theoretical analysis and interpretation of adsorption isotherm from the excess isotherm were conducted using Pseudo Ideal Adsorption, Gibbs Dividing Plane Model and Langmuir-Fruendlich binary isotherm model. For organic solvents, acetone and propanol were chosen as the adsorbates due to the non-azeotropic properties in the mixture. Activated carbon and silicalite were chosen as adsorbents due to the different in their porosity such as macro porous and micro porous structure. The result of the study has revealed that the adsorption isotherm of non-azeotropic mixture onto activated carbon and silicalite can be interpreted as monolayer type of adsorption.

  14. Computational Multiqubit Tunnelling in Programmable Quantum Annealers

    Science.gov (United States)

    2016-08-25

    height in Fig. 2 for different values of s (Fig. 7). A disadvantage of SVMC as outlined above and introduced in ref. 20 is that there is no natural...be an important future task to determine the maximal K attainable by current technology and how large it can be made in next generations. The...annealing of a disordered spin system. Science 284, 779–781 (1999). 5. Santoro, G. E., Martoňák, R., Tosatti, E. & Car, R. Theory of quantum annealing of an

  15. Effect of annealing on intrinsic magnetic properties in experimentally shocked magnetite

    Science.gov (United States)

    Kontny, Agnes; Reznik, Boris; Boubnov, Alexey; Göttlicher, Jörg; Steininger, Ralph

    2017-04-01

    Magnetite is an important magnetic carrier on planetary bodies and one of the most significant magnetic minerals in shocked crustal rocks on Earth. This study focuses on the intrinsic magnetic properties and chemical stability of magnetite, shocked experimentally between 5 and 30 GPa and subsequently heated in argon atmosphere up to 700°C. From pre-shocked, shocked and afterwards annealed samples temperature-dependent magnetic susceptibility and saturation isothermal magnetization as well as the Curie and Verwey transition temperature were measured. Shocked magnetite used for the heating experiments is characterized by decreasing magnetic susceptibility, increasing SIRM, a multidomain to pseudo single domain transition, and a decrease in apparent crystallite size seen in X-ray diffraction pattern with increasing shock pressure (Reznik et al., 2016). All these features are in agreement with magnetic domain size reduction caused either by grain fragmentation or a pinning of domain walls at crystal defects and dislocations. However, an increasing width and temperature of the Verwey transition, along with a very small expansion in the lattice cell parameter indicates also distortion of the tetrahedral and octahedral crystal sites. Annealing of the shocked samples strongly modifies the intrinsic magnetic properties and suggests a significant amount of non-permanent magnetic changes in impacted rocks. Therefore, special attention was given to the identification of the iron oxidation state and its coordination geometry in shocked and annealed magnetite using synchrotron-assisted X-ray absorption spectroscopy. In addition to defect healing, the ordering of ferric and ferrous iron on tetrahedral and octahedral sites seems to play a crucial role in the interpretation of the intrinsic magnetic properties modifications in shocked and annealed magnetite. Reznik, B., Kontny, A., Fritz, J., Gerhards, U., 2016, Shock-induced deformation phenomena in magnetite and their

  16. Effect of thermal annealing on structural properties of GeSn thin films grown by molecular beam epitaxy

    Science.gov (United States)

    Zhang, Z. P.; Song, Y. X.; Li, Y. Y.; Wu, X. Y.; Zhu, Z. Y. S.; Han, Y.; Zhang, L. Y.; Huang, H.; Wang, S. M.

    2017-10-01

    GeSn alloy with 7.68% Sn concentration grown by molecular beam epitaxy has been rapidly annealed at different temperatures from 300°C to 800°C. Surface morphology and roughness annealed below or equal to 500°C for 1 min have no obvious changes, while the strain relaxation rate increasing. When the annealing temperature is above or equal to 600°C, significant changes occur in surface morphology and roughness, and Sn precipitation is observed at 700°C. The structural properties are analyzed by reciprocal space mapping in the symmetric (004) and asymmetric (224) planes by high resolution X-ray diffraction. The lateral correlation length and the mosaic spread are extracted for the epi-layer peaks in the asymmetric (224) diffraction. The most suitable annealing temperature to improve both the GeSn lattice quality and relaxation rate is about 500°C.

  17. Exploring the problem of mold growth and the efficacy of various mold inhibitor methods during moisture sorption isotherm measurements.

    Science.gov (United States)

    Yu, X; Martin, S E; Schmidt, S J

    2008-03-01

    Mold growth is a common problem during the equilibration of food materials at high relative humidity values using the standard saturated salt slurry method. Exposing samples to toluene vapor and mixing samples with mold inhibitor chemicals are suggested methods for preventing mold growth while obtaining isotherms. However, no published research was found that examined the effect of mold growth on isotherm performance or the efficacy of various mold inhibitor methods, including their possible effect on the physicochemical properties of food materials. Therefore, the objectives of this study were to (1) explore the effect of mold growth on isotherm performance in a range of food materials, (2) investigate the effectiveness of 4 mold inhibitor methods, irradiation, 2 chemical inhibitors (potassium sorbate and sodium acetate), and toluene vapor, on mold growth on dent corn starch inoculated with A. niger, and (3) examine the effect of mold inhibitor methods on the physicochemical properties of dent corn starch, including isotherm performance, pasting properties, gelatinization temperature, and enthalpy. Mold growth was found to affect starch isotherm performance by contributing to weight changes during sample equilibration. Among the 4 mold inhibitor methods tested, irradiation and toluene vapor were found to be the most effective for inhibiting growth of A. niger on dent cornstarch. However, both methods exhibited a significant impact on the starches' physiochemical properties, suggesting the need to probe the efficacy of other mold inhibitor methods and explore the use of new rapid isotherm instruments, which hamper mold growth by significantly decreasing measurement time.

  18. Defect annealing processes for polycrystalline silicon thin-film solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Steffens, S., E-mail: simon.steffens@helmholtz-berlin.de [Helmholtz-Zentrum Berlin, Berlin (Germany); Becker, C. [Helmholtz-Zentrum Berlin, Berlin (Germany); Zollondz, J.-H., E-mail: hzollondz@masdarpv.com [CSG Solar AG, Thalheim (Germany); Chowdhury, A.; Slaoui, A. [L’Institut d’Électronique du Solide et des Systèmes, Strasbourg (France); Lindekugel, S. [Fraunhofer-Institut für Solare Energiesysteme, Freiburg (Germany); Schubert, U.; Evans, R. [Suntech R and D Australia Pty Ltd, Sydney (Australia); Rech, B. [Helmholtz-Zentrum Berlin, Berlin (Germany)

    2013-05-15

    Highlights: ► Defect annealing processes were applied to polycrystalline silicon thin films. ► Conventional rapid thermal annealing was compared to novel annealing processes using a laser system and a zone-melting recrystallization setup. ► The open circuit voltages could be enhanced from below 170 mV up to 482 mV. ► Increase in Sun's-V{sub OC} values with decrease in FWHM of the TO Raman phonon of crystalline silicon. ► Solar cells were fabricated for I–V-measurements: Best solar cell efficiency of 6.7%. -- Abstract: A variety of defect healing methods was analyzed for optimization of polycrystalline silicon (poly-Si) thin-film solar cells on glass. The films were fabricated by solid phase crystallization of amorphous silicon deposited either by plasma enhanced chemical vapor deposition (PECVD) or by electron-beam evaporation (EBE). Three different rapid thermal processing (RTP) set-ups were compared: A conventional rapid thermal annealing oven, a dual wavelength laser annealing system and a movable two sided halogen lamp oven. The two latter processes utilize focused energy input for reducing the thermal load introduced into the glass substrates and thus lead to less deformation and impurity diffusion. Analysis of the structural and electrical properties of the poly-Si thin films was performed by Suns-V{sub OC} measurements and Raman spectroscopy. 1 cm{sup 2} cells were prepared for a selection of samples and characterized by I–V-measurements. The poly-Si material quality could be extremely enhanced, resulting in increase of the open circuit voltages from about 100 mV (EBE) and 170 mV (PECVD) in the untreated case up to 480 mV after processing.

  19. influence of intercritical annealing temperature on mechanical

    African Journals Online (AJOL)

    User

    Mechanical testing. (tensile, impact and hardness) of the annealed samples were conducted at room temperature. The fracture surfaces of the impact test samples were examined using the scanning electron microscope (SEM). Micros structural ... improved formability, capacity to absorb crash energy and ability to resist ...

  20. Thermal annealing in neutron-irradiated tribromobenzenes

    DEFF Research Database (Denmark)

    Siekierska, K.E.; Halpern, A.; Maddock, A. G.

    1968-01-01

    The distribution of 82Br among various products in neutron-irradiated isomers of tribromobenzene has been investigated, and the effect of thermal annealing examined. Reversed-phase partition chromatography was employed for the determination of radioactive organic products, and atomic bromine...

  1. Hierarchical Network Design Using Simulated Annealing

    DEFF Research Database (Denmark)

    Thomadsen, Tommy; Clausen, Jens

    2002-01-01

    networks are described and a mathematical model is proposed for a two level version of the hierarchical network problem. The problem is to determine which edges should connect nodes, and how demand is routed in the network. The problem is solved heuristically using simulated annealing which as a sub...

  2. influence of intercritical annealing temperature on mechanical

    African Journals Online (AJOL)

    User

    of the impact test samples were examined using the scanning electron microscope (SEM). Micros structural evolution of the samples was also examined with an optical microscope. The results showed that all the evaluated mechanical properties were improved by intercritical annealing, with the samples treated at 790OC ...

  3. Non-isothermal crystallization kinetics of As30Te60Ga10 glass

    Science.gov (United States)

    Mohamed, Mansour; Abd-Elnaiem, Alaa M.; Hassan, R. M.; Abdel-Rahim, M. A.; Hafiz, M. M.

    2017-08-01

    The crystallization study under non-isothermal conditions of As30Te60Ga10 glass was investigated. The studied composition was synthesized by melt-quenching technique and characterized by different techniques such as X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and differential scanning calorimetry (DSC). The XRD analysis revealed that the as-prepared and annealed bulk glass of As30Te60Ga10 exhibit the amorphous, and polycrystalline nature, respectively. The DSC results showed that the heating rate affects the characteristic temperatures, for instance, the glass transition, onset, and peak crystallization temperatures. Furthermore, some thermal analysis methods such as the Kissinger and Matusita et al., approximations were employed to determine the crystallization parameters: for example Avrami exponent and the activation energies for glass transition and crystallization process. In addition, we have compared the experimental DSC data with the calculated ones based on the Johnson-Mehl-Avrami (JMA) and Sestak-Berggren SB(M,N) models. The results indicated that the SB(M,N) model is more suitable for describing the non-isothermal crystallization kinetics of the investigated composition.

  4. Isothermal Gravitational Segregation: Algorithms and Specifications

    DEFF Research Database (Denmark)

    Halldórsson, Snorri; Stenby, Erling Halfdan

    2000-01-01

    New algorithms for calculating the isothermal equilibrium state of reservoir fluids under the influence of gravity are presented. Two types of specifications are considered: the specification of pressure and composition at a reference depth; and the specification of the total overall content...... of the reservoir, along with the reservoir geometry. It is shown how both types of calculations can be performed in an efficient and robust manner using volume-based thermodynamics. The new method makes it possible to evaluate the influence of reservoir geometry and gravity segregation on the hydrocarbon reserves...

  5. Diagnosis of brugian filariasis by loop-mediated isothermal amplification.

    Directory of Open Access Journals (Sweden)

    Catherine B Poole

    Full Text Available In this study we developed and evaluated a Brugia Hha I repeat loop-mediated isothermal amplification (LAMP assay for the rapid detection of Brugia genomic DNA. Amplification was detected using turbidity or fluorescence as readouts. Reactions generated a turbidity threshold value or a clear visual positive within 30 minutes using purified genomic DNA equivalent to one microfilaria. Similar results were obtained using DNA isolated from blood samples containing B. malayi microfilariae. Amplification was specific to B. malayi and B. timori, as no turbidity was observed using DNA from the related filarial parasites Wuchereria bancrofti, Onchocerca volvulus or Dirofilaria immitis, or from human or mosquito. Furthermore, the assay was most robust using a new strand-displacing DNA polymerase termed Bst 2.0 compared to wild-type Bst DNA polymerase, large fragment. The results indicate that the Brugia Hha I repeat LAMP assay is rapid, sensitive and Brugia-specific with the potential to be developed further as a field tool for diagnosis and mapping of brugian filariasis.

  6. Crystallization kinetics of the Cu50Zr50 metallic glass under isothermal conditions

    Science.gov (United States)

    Gao, Qian; Jian, Zengyun; Xu, Junfeng; Zhu, Man; Chang, Fange; Han, Amin

    2016-12-01

    Amorphous structure of the melt-spun Cu50Zr50 amorphous alloy ribbons were confirmed by X-ray diffraction (XRD) and high-resolution transmission electron microscopy (HR-TEM). Isothermal crystallization kinetics of these alloy ribbons were investigated using differential scanning calorimetry (DSC). Besides, Arrhenius and Johnson-Mehl-Avrami (JMA) equations were utilized to obtain the isothermal crystallization kinetic parameters. As shown in the results, the local activation energy Eα decreases by a large margin at the crystallized volume fraction αbasically constant at 0.1<α<0.9. Therefore, it turns out that the unchanged barrier is overcome in the crystallization process. Finally, Eα rapidly decreases at 0.9<α<1, implying that crystallization becomes easier and easier to proceed. Nucleation activation energy Enucleation is greater than growth activation energy Egrowth, so nucleation is harder than growth in isothermal process. In terms of the local Avrami exponent n(α), it ranges 1.1-7.4, revealing that isothermal crystallization mechanism is interface-controlled one- two- or three-dimensional growth with different nucleation rates.

  7. Development of one-step Loop-Mediated Isothermal Amplification (LAMP) for the detection of norovirus in oysters

    Science.gov (United States)

    The aim of this study was to develop a simple and rapid technique for detecting human norovirus (NoV). The loop-mediated isothermal amplification (LAMP) technique was evaluated and found to be sensitive, highly specific, and useful for routine oyster testing. Reverse transcription-LAMP (RT-LAMP) pri...

  8. Intense pulsed light annealing of copper zinc tin sulfide nanocrystal coatings

    Energy Technology Data Exchange (ETDEWEB)

    Williams, Bryce A.; Smeaton, Michelle A.; Holgate, Collin S.; Trejo, Nancy D.; Francis, Lorraine F., E-mail: francis@umn.edu; Aydil, Eray S., E-mail: aydil@umn.edu [Department of Chemical Engineering and Materials Science, University of Minnesota, 151 Amundson Hall, 421 Washington Avenue SE, Minneapolis, Minnesota 55455 (United States)

    2016-09-15

    A promising method for forming the absorber layer in copper zinc tin sulfide [Cu{sub 2}ZnSnS{sub 4} (CZTS)] thin film solar cells is thermal annealing of coatings cast from dispersions of CZTS nanocrystals. Intense pulsed light (IPL) annealing utilizing xenon flash lamps is a potential high-throughput, low-cost, roll-to-roll manufacturing compatible alternative to thermal annealing in conventional furnaces. The authors studied the effects of flash energy density (3.9–11.6 J/cm{sup 2}) and number of flashes (1–400) during IPL annealing on the microstructure of CZTS nanocrystal coatings cast on molybdenum-coated soda lime glass substrates (Mo-coated SLG). The annealed coatings exhibited cracks with two distinct linear crack densities, 0.01 and 0.2 μm{sup −1}, depending on the flash intensity and total number of flashes. Low density cracking (0.01 μm{sup −1}, ∼1 crack per 100 μm) is caused by decomposition of CZTS at the Mo-coating interface. Vapor decomposition products at the interface cause blisters as they escape the coating. Residual decomposition products within the blisters were imaged using confocal Raman spectroscopy. In support of this hypothesis, replacing the Mo-coated SLG substrate with quartz eliminated blistering and low-density cracking. High density cracking is caused by rapid thermal expansion and contraction of the coating constricted on the substrate as it is heated and cooled during IPL annealing. Finite element modeling showed that CZTS coatings on low thermal diffusivity materials (i.e., SLG) underwent significant differential heating with respect to the substrate with rapid rises and falls of the coating temperature as the flash is turned on and off, possibly causing a build-up of tensile stress within the coating prompting cracking. Use of a high thermal diffusivity substrate, such as a molybdenum foil (Mo foil), reduces this differential heating and eliminates the high-density cracking. IPL annealing in presence of sulfur

  9. ISOTHERMAL PYROLYSIS OF KRAFT PULP MILL SLUDGE

    Directory of Open Access Journals (Sweden)

    Syamsudin Syamsudin

    2014-12-01

    Full Text Available Kraft pulp mill sludge cake composed of rejected wood fibers and activated sludge microorganisms. With a heating value about 14 MJ/kg (dried basis, this type of biomass had a potential as an alternative energy source. Unfortunately, it had an ash content of 27.6% and a moisture content of 80%. For reducing moisture content with minimum energy consumption, a combination of mechanical dewatering and thermal drying was studied previously. Meanwhile, experiments on isothermal pyrolysis had been carried out for further improvement on ultimate and proximate analysis of solid fuel. Final mass of char obtained from pyrolysis at 500oC was not significantly different from that of 700oC, so pyrolysis was considered to be optimum at 500oC. A char obtained from pyrolysis at temperature of 500oC had a pore surface area of 77.049 m2/g (highest among other temperatures. Kinetic of isothermal pyrolysis was well represented with a first order modified volumetric model with a frequency factor of 0.782 1/s and an activation of 34.050 kJ/mol.

  10. A note on simulated annealing to computer laboratory scheduling ...

    African Journals Online (AJOL)

    The concepts, principles and implementation of simulated Annealing as a modem heuristic technique is presented. Simulated Annealing algorithm is used in solving real life problem of Computer Laboratory scheduling in order to maximize the use of scarce and insufficient resources. KEY WORDS: Simulated Annealing ...

  11. Moisture sorption isotherms of cereals at different temperatures.

    Science.gov (United States)

    Ertugay, M F; Certel, M

    2000-04-01

    In this research, moisture sorption isotherms of wheat (Kink and Lancer) barley, rye, oat and corn were determined at 20, 25, 35, 50 and 70 degrees C. The sorption isotherm curves of all cereal samples showed the characteristics of type II isotherm. This indicated that the adsorption occurred in cereal samples was a multilayer adsorption and cereal samples were of a microcapillary structure. In addition, the adsorption in cereal samples decreased as temperature increased.

  12. Minority carrier lifetime in furnace and E-beam annealed CZ silicon

    Energy Technology Data Exchange (ETDEWEB)

    Susi, E.; Lulli, G.; Passari, L.

    1987-05-01

    Thermally induced defects in CZ silicon are studied, with the aim of identifying the mechanisms responsible for lifetime changes and the role of oxygen in them. For low temperature heatings lifetime can either decrease or increase: a gettering activity of neutral oxygen clusters which participate in the dissociation equilibria of Fe-B pairs is postulated. The effects of pretreatments performed by a conventional diffusion furnace or by rapid thermal annealing are discussed.

  13. Isothermal Amplification and Lateral-Flow Assay for Detecting Crown-Gall-Causing Agrobacterium spp.

    Science.gov (United States)

    Fuller, Skylar L; Savory, Elizabeth A; Weisberg, Alexandra J; Buser, Jessica Z; Gordon, Michael I; Putnam, Melodie L; Chang, Jeff H

    2017-09-01

    Agrobacterium is a genus of soilborne gram-negative bacteria. Members carrying oncogenic plasmids can cause crown gall disease, which has significant economic costs, especially for the orchard and nursery industries. Early and rapid detection of pathogenic Agrobacterium spp. is key to the management of crown gall disease. To this end, we designed oligonucleotide primers and probes to target virD2 for use in a molecular diagnostic tool that relies on isothermal amplification and lateral-flow-based detection. The oligonucleotide tools were tested in the assay and evaluated for detection limit and specificity in detecting alleles of virD2. One set of primers that successfully amplified virD2 when used with an isothermal recombinase was selected. Both tested probes had detection limits in picogram amounts of DNA. Probe 1 could detect all tested pathogenic isolates that represented most of the diversity of virD2. Finally, the coupling of lateral-flow detection to the use of these oligonucleotide primers in isothermal amplification helped to reduce the onerousness of the process, and alleviated reliance on specialized tools necessary for molecular diagnostics. The assay is an advancement for the rapid molecular detection of pathogenic Agrobacterium spp.

  14. Dynamical Frustration in ANNNI Model and Annealing

    Science.gov (United States)

    Sen, Parongama; Das, Pratap K.

    Simulated annealing is usually applied to systems with frustration, like spin glasses and optimisation problems, where the energy landscape is complex with many spurious minima. There are certain other systems, however, which have very simple energy landscape picture and ground states, but still the system fails to reach its ground state during a energy-lowering dynamical process. This situation corresponds to "dynamical frustration ". We have specifically considered the case of the axial next nearest neighbour (ANNNI) chain, where such a situation is encountered. In Sect. II, we elaborate the notion of dynamic frustration with examples and in Sect. III, the dynamics in ANNNI model is discussed in detail. The results of application of the classical and quantum annealing are discussed in Sects. IV and V. Summary and some concluding comments are given in the last section.

  15. Isothermal and non-isothermal sublimation kinetics of zirconium tetrachloride (ZrCl{sub 4}) for producing nuclear grade Zr

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Jae Hong [Department of Materials Engineering, Hanyang University, Ansan 426-791 (Korea, Republic of); Choi, Mi Sun [Research Institute of Industrial Science and Technology (RIST), Pohang 790-330 (Korea, Republic of); Min, Dong Joon [Department of Materials Science and Engineering, Yonsei University, Seoul 120-749 (Korea, Republic of); Park, Joo Hyun, E-mail: basicity@hanyang.ac.kr [Department of Materials Engineering, Hanyang University, Ansan 426-791 (Korea, Republic of)

    2014-02-14

    Sublimation of ZrCl{sub 4} is important for the production of nuclear grade metallic Zr in Kroll's process. The sublimation kinetics of ZrCl{sub 4} was investigated by thermogravimetric analysis under both isothermal and non-isothermal conditions. The sublimation rate of ZrCl{sub 4} increased with increasing temperature under isothermal conditions. ZrCl{sub 4} sublimation was confirmed to be a zero-order process under isothermal conditions, whereas it was first-order kinetics under non-isothermal conditions. The activation energy of ZrCl{sub 4} sublimation under isothermal conditions was 21.7 kJ mol{sup −1}. The activation energy for non-isothermal sublimation was 101.4 kJ mol{sup −1} and 108.1 kJ mol{sup −1} with the Kissinger method and Flynn–Wall–Ozawa method, respectively. These non-isothermal activation energies were very close to the heat of sublimation (103.3 kJ mol{sup −1}). Sublimation occurs by two elementary steps: surface reaction and desorption. Therefore, the overall activation energy of ZrCl{sub 4} sublimation is 104.8 (±3.4) kJ mol{sup −1}. The activation energy of the surface reaction and desorption steps are proposed to be 83.1 kJ mol{sup −1} and 21.7 kJ mol{sup −1}, respectively. - Highlights: • Sublimation kinetics of ZrCl{sub 4} was quantitatively analyzed using TGA method. • Isothermal and non-isothermal sublimation kinetics were quantitatively evaluated. • Activation energies of isothermal and non-isothermal kinetics were obtained. • Sublimation mechanism was proposed from kinetic analyses and SEM observations. • This kinetic information will be very useful in production of nuclear grade Zr.

  16. A Laboratory to Demonstrate the Effect of Thermal History on Semicrystalline Polymers Using Rapid Scanning Rate Differential Scanning Calorimetry

    Science.gov (United States)

    Badrinarayanan, Prashanth; Kessler, Michael R.

    2010-01-01

    A detailed understanding of the effect of thermal history on the thermal properties of semicrystalline polymers is essential for materials scientists and engineers. In this article, we describe a materials science laboratory to demonstrate the effect of parameters such as heating rate and isothermal annealing conditions on the thermal behavior of…

  17. Entanglement in a Quantum Annealing Processor

    Science.gov (United States)

    2016-09-07

    Entanglement in a Quantum Annealing Processor T. Lanting,1,* A. J. Przybysz,1 A. Yu. Smirnov,1 F. M. Spedalieri,2,3 M. H. Amin,1,4 A. J. Berkley,1 R...promising path to a practical quantum processor . We have built a series of architecturally scalable QA processors consisting of networks of manufactured...such processor , demonstrating quantum coherence in these systems. We present experimental evidence that, during a critical portion of QA, the qubits

  18. Simulated annealing algorithm for optimal capital growth

    Science.gov (United States)

    Luo, Yong; Zhu, Bo; Tang, Yong

    2014-08-01

    We investigate the problem of dynamic optimal capital growth of a portfolio. A general framework that one strives to maximize the expected logarithm utility of long term growth rate was developed. Exact optimization algorithms run into difficulties in this framework and this motivates the investigation of applying simulated annealing optimized algorithm to optimize the capital growth of a given portfolio. Empirical results with real financial data indicate that the approach is inspiring for capital growth portfolio.

  19. Isothermal titration calorimetry of supramolecular polymers.

    Science.gov (United States)

    Arnaud, Alix; Bouteiller, Laurent

    2004-08-03

    A method to characterize the self-association of supramolecular polymers by isothermal titration calorimetry (ITC) has been designed. Association constants in the range 10(4)-10(6) dm(3) mol(-1) have been successfully determined from the heat exchange occurring when a supramolecular polymer solution is injected into a calorimetric cell containing pure solvent. Very good agreement with literature values has been obtained. Compared to other techniques (such as NMR or Fourier transform infrared spectroscopy), the use of ITC presents several advantages: (i) the enthalpy of association is obtained together with the association constant from the same experiment, (ii) the measurements can be performed in almost any solvent, and (iii) systems with higher association constants can be characterized.

  20. Simulated annealing with probabilistic analysis for solving traveling salesman problems

    Science.gov (United States)

    Hong, Pei-Yee; Lim, Yai-Fung; Ramli, Razamin; Khalid, Ruzelan

    2013-09-01

    Simulated Annealing (SA) is a widely used meta-heuristic that was inspired from the annealing process of recrystallization of metals. Therefore, the efficiency of SA is highly affected by the annealing schedule. As a result, in this paper, we presented an empirical work to provide a comparable annealing schedule to solve symmetric traveling salesman problems (TSP). Randomized complete block design is also used in this study. The results show that different parameters do affect the efficiency of SA and thus, we propose the best found annealing schedule based on the Post Hoc test. SA was tested on seven selected benchmarked problems of symmetric TSP with the proposed annealing schedule. The performance of SA was evaluated empirically alongside with benchmark solutions and simple analysis to validate the quality of solutions. Computational results show that the proposed annealing schedule provides a good quality of solution.

  1. Postshock Annealing and Postannealing Shock in Equilibrated Ordinary Chondrites: Implications for the Thermal and Shock Histories of Chondritic Asteroids

    Science.gov (United States)

    Rubin, Alan E.

    2006-01-01

    In addition to shock effects in olivine, plagioclase, orthopyroxene and Ca-pyroxene, petrographic shock indicators in equilibrated ordinary chondrites (OC) include chromite veinlets, chromite-plagioclase assemblages, polycrystalline troilite, metallic Cu, irregularly shaped troilite grains within metallic Fe-Ni, rapidly solidified metal-sulfide intergrowths, martensite and various types of plessite, metal-sulfide veins, large metal and/or sulfide nodules, silicate melt veins, silicate darkening, low-Ca clinopyroxene, silicate melt pockets, and large regions of silicate melt. The presence of some of these indicators in every petrologic type-4 to -6 ordinary chondrite (OC) demonstrates that collisional events caused all equilibrated OC to reach shock stages S3-S6. Those type-4 to -6 OC that are classified as shock-stage S1 (on the basis of sharp optical extinction in olivine) underwent postshock annealing due to burial beneath materials heated by the impact event. Those type-4 to -6 OC that are classified S2 (on the basis of undulose extinction and lack of planar fractures in olivine) were shocked to stage S3-S6, annealed to stage S1 and then shocked again to stage S2. Some OC were probably shocked to stage 253 after annealing. It seems likely that many OC experienced multiple episodes of shock and annealing. Because 40Ar-39Ar chronological data indicate that MIL 99301 (LL6, Sl) was annealed approximately 4.26 Ga ago, presumably as a consequence of a major impact, it seems reasonable to suggest that other equilibrated S1 and S2 OC (which contain relict shock features) were also annealed by impacts. Because some type-6 S1 OC (e.g., Guarena, Kernouve, Portales Valley, all of which contain relict shock features) were annealed 4.44-4.45 Ga ago (during a period when impacts were prevalent and most OC were thermally metamorphosed), it follows that impact-induced annealing could have contributed significantly to OC thermal metamorphism.

  2. Moisture sorption isotherms of dehydrated whey proteins

    Directory of Open Access Journals (Sweden)

    Suzana Rimac Brnčić

    2010-03-01

    Full Text Available Moisture sorption isotherms describe the relation between the moisture content of the dry material (food and relative humidity of the surrounding environment. The data obtained are important in modelling of drying process conditions, packaging and shelf-life stability of food that will provide maximum retaining of aroma, colour and texture as well as nutritive and biological value. The objective of this research was to establish the equilibrium moisture content and water activity, as well as monolayer value of two commercial powdered whey protein isolates before and after tribomechanical micronisation and enzymatic hydrolysis, respectively. At the same time it was necessary to evaluate the best moisture sorption isotherm equation to fit the experimental data. The equilibrium moisture contents in investigated samples were determined using standard gravimetric method at 20 °C. The range of water activities was 0.11 to 0.75. The monolayer moisture content was estimated from sorption data using Brunauer-Emmett-Teller (BET and Guggenheim-Anderson-de Boer (GAB models. The results have shown that tribomechanically treated whey protein isolates as well as protein hydrolizates had lower monolayer moisture content values as well as higher corresponding water activity. Therefore, in spite of the fact that they have lower moisture content, they can be storage at higher relative humidity compared to untreated samples. BET model gave better fit to experimental sorption data for a water activity range from 0.11-0.54, while GAB model gave the closest fit for a water activity to 0.75.

  3. Zn Diffusion and α-Fe(Zn) Layer Growth During Annealing of Zn-Coated B Steel

    Science.gov (United States)

    Janik, Vit; Lan, Yongjun; Beentjes, Peter; Norman, David; Hensen, Guido; Sridhar, Seetharaman

    2016-01-01

    Direct hot press forming of Zn-coated 22MnB5 steels is impeded by micro-cracks that occur in the substrate due to the presence of Zn during the forming process. A study was therefore undertaken to quantify concentration of Zn across the α-Fe(Zn) coating and on grain boundaries in the α-Fe(Zn) layer and the underlying γ-Fe(Zn) substrate after isothermal annealing of Zn-coated 22MnB5 at 1173 K (900 °C) and to link the Zn distribution to the amount and type of micro-cracks observed in deformed samples. Finite difference model was developed to describe Zn diffusion and the growth of the α-Fe(Zn) layer. The penetration of Zn into the γ-Fe(Zn) substrate after 600 seconds annealing at 1173 K (900 °C) through bulk diffusion is estimated to be 3 μm, and the diffusion depth of Zn on the γ-Fe(Zn) grain boundaries is estimated to be 6 μm, which is significantly shorter than the maximum length (15 to 50 μm) of the micro-cracks formed in the severely stressed conditions, indicating that the Zn diffusion into the γ-Fe(Zn) from the α-Fe(Zn) during annealing is not correlated to the depth of micro-cracks. On the other hand, the maximum amount of Zn present in α-Fe(Zn) layer decreases with annealing time as the layer grows and Zn oxidizes, and the amount of Zn-enriched areas inside the α-Fe(Zn) layer is reduced leading to reduced length of cracking. Solid-Metal-Induced Embrittlement mechanism is proposed to explain the benefit of extended annealing on reduced depth of micro-crack penetration into the γ-Fe(Zn) substrate.

  4. High-throughput investigation of single and binary protein adsorption isotherms in anion exchange chromatography employing multivariate analysis.

    Science.gov (United States)

    Field, Nicholas; Konstantinidis, Spyridon; Velayudhan, Ajoy

    2017-08-11

    The combination of multi-well plates and automated liquid handling is well suited to the rapid measurement of the adsorption isotherms of proteins. Here, single and binary adsorption isotherms are reported for BSA, ovalbumin and conalbumin on a strong anion exchanger over a range of pH and salt levels. The impact of the main experimental factors at play on the accuracy and precision of the adsorbed protein concentrations is quantified theoretically and experimentally. In addition to the standard measurement of liquid concentrations before and after adsorption, the amounts eluted from the wells are measured directly. This additional measurement corroborates the calculation based on liquid concentration data, and improves precision especially under conditions of weak or moderate interaction strength. The traditional measurement of multicomponent isotherms is limited by the speed of HPLC analysis; this analytical bottleneck is alleviated by careful multivariate analysis of UV spectra. Copyright © 2017. Published by Elsevier B.V.

  5. Effects of Thermal Annealing Upon the Morphology of Polymer-Fullerene Blends

    KAUST Repository

    Verploegen, Eric

    2010-08-18

    Grazing incidence X-ray scattering (GIXS) is used to characterize the morphology of poly(3-hexylthiophene) (P3HT)-phenyl-C61-butyric acid methyl ester (PCBM) thin film bulk heterojunction (BHJ) blends as a function of thermal annealing temperature, from room temperature to 220 °C. A custom-built heating chamber for in situ GIXS studies allows for the morphological characterization of thin films at elevated temperatures. Films annealed with a thermal gradient allow for the rapid investigation of the morphology over a range of temperatures that corroborate the results of the in situ experiments. Using these techniques the following are observed: the melting points of each component; an increase in the P3HT coherence length with annealing below the P3HT melting temperature; the formation of well-oriented P3HT crystallites with the (100) plane parallel to the substrate, when cooled from the melt; and the cold crystallization of PCBM associated with the PCBM glass transition temperature. The incorporation of these materials into BHJ blends affects the nature of these transitions as a function of blend ratio. These results provide a deeper understanding of the physics of how thermal annealing affects the morphology of polymer-fullerene BHJ blends and provides tools to manipulate the blend morphology in order to develop high-performance organic solar cell devices. © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Microstructural Coarsening during Thermomechanical Fatigue and Annealing of Micro Flip-Chip Solder Joints

    Energy Technology Data Exchange (ETDEWEB)

    Barney, Monica Michele [Univ. of California, Berkeley, CA (United States)

    1998-12-01

    Microstructural evolution due to thermal effects was studied in micro solder joints (55 ± 5 μm). The composition of the Sn/Pb solder studied was found to be hypereutectic with a tin content of 65-70 wt%.This was determined by Energy Dispersive X-ray analysis and confirmed with quantitative stereology. The quantitative stereological value of the surface-to-volume ratio was used to characterize and compare the coarsening during thermal cycling from 0-160 C to the coarsening during annealing at 160 C. The initial coarsening of the annealed samples was more rapid than the cycled samples, but tapered off as time to the one-half as expected. Because the substrates to which the solder was bonded have different thermal expansion coefficients, the cycled samples experienced a mechanical strain with thermal cycling. The low-strain cycled samples had a 2.8% strain imposed on the solder and failed by 1,000 cycles, despite undergoing less coarsening than the annealed samples. The high-strain cycled samples experienced a 28% strain and failed between 25 and 250 cycles. No failures were observed in the annealed samples. Failure mechanisms and processing issues unique to small, fine pitch joints are also discussed.

  7. New Theoretical Expressions for the Five Adsorption Type Isotherms ...

    African Journals Online (AJOL)

    The physico-chemical parameters intervening in the adsorption process that present the models could deduced directly from the adsorption isotherms with numerical simulation. We determine the adequate model for each Type isotherm, which fixes with direct numerical simulation the monlayer, multilayer or condensation ...

  8. Non-isothermal crystallization kinetics and thermal behaviour of ...

    Indian Academy of Sciences (India)

    Administrator

    Abstract. The thermal behaviour and crystallization kinetics of PA12/SEBS-g-MA blends were investigated under non-isothermal and isothermal conditions using thermogravimetric analysis and differential scanning calorimetry, respectively. The macrokinetic model given by Avrami was used to analyse both the non-.

  9. Synthesis, characterization and isotherm studies of new composite ...

    Indian Academy of Sciences (India)

    Sorption isotherm studies of La 3 + , Ce 3 + , Nd 3 + and Sm 3 + ions were performed at differentreaction temperatures and analysed by Langmuir, Freundlich, Dubinin–Raduchkivich and Temkin isotherm models. Thermodynamic parameters such as Δ G ∘ , Δ H ∘ and Δ S ∘ were determined and found to be endothermic ...

  10. Non-isothermal crystallization kinetics of polyethylene–clay ...

    Indian Academy of Sciences (India)

    Administrator

    Abstract. Non-isothermal crystallization kinetics of pure medium density polyethylene (MDPE) and MDPE– clay nanocomposites have been investigated by differential scanning calorimeter. The modified Avrami,. Ozawa, Liu and Ziabicki equations have been applied to describe non-isothermal crystallization process. The.

  11. Modeling polychlorinated biphenyl sorption isotherms for soot and coal

    NARCIS (Netherlands)

    Jantunen, A.P.K.; Koelmans, A.A.; Jonker, M.T.O.

    2010-01-01

    Sorption isotherms (pg-ng/L) were measured for 11 polychlorinated biphenyls (PCBs) of varying molecular planarity from aqueous solution to two carbonaceous geosorbents, anthracite coal and traffic soot. All isotherms were reasonably log-log-linear, but smooth for traffic soot and staircase-shaped

  12. Estimation of Specific Surface Area using Langmuir Isotherm ...

    African Journals Online (AJOL)

    Michael Horsfall

    ABSTRACT: A comparison of four widely used linear equations of the Langmuir types of isotherm (The. Langmuir Type 1, 2, 3 and 4 ) were examined in an experiment using dye sorption onto derived acid and salt treated Fish Activated Carbon (H3PO4-FAC and ZnCl2-FAC respectively). Isotherm parameters obtained.

  13. Synthesis, non-isothermal crystallization and magnetic properties of ...

    Indian Academy of Sciences (India)

    A non-isothermal study of the crystallization kinetic of ferrite/PEVA nanocomposite was carried out by differential scanning calorimetry (DSC), scanning electron microscope (SEM) and X-ray diffraction (XRD) techniques. It was observed that the Ozawa equation describes perfectly the primary process of non-isothermal ...

  14. Speeds of sound and isothermal compressibility of ternary liquid ...

    Indian Academy of Sciences (India)

    The isothermal compressibility of these mixtures has also been computed theoretically using different models for hard sphere equations of state and Flory's statistical theory. Computed values of isothermal compressibility have been compared with experimental findings. A satisfactory agreement has been observed.

  15. An improved experimental and regression methodology for sorption isotherms

    NARCIS (Netherlands)

    Quirijns, E.J.; Boxtel, van A.J.B.; Loon, van W.K.P.; Straten, van G.

    2005-01-01

    Sorption isotherms of corn and starch cylinders with immobilised catalase are experimentally determined at different temperatures for use in drying models in optimal control studies. This application of the sorption isotherm requires an accurate prediction of the sorption data at different

  16. Synthesis, characterization and isotherm studies of new composite ...

    Indian Academy of Sciences (India)

    1Atomic Energy Authority, Hot Labs Center, Cairo 13759, Egypt. 2Faculty of Science, Chemistry Department, ... coagulation, sedimentation, flotation, filtration, membrane processes, electrochemical techniques, ion ...... isotherm relating to the amount of gas adsorbed on a surface. Now, this model is a well-known isotherm ...

  17. Adsorption isotherms and kinetics for dibenzothiophene on activated ...

    Indian Academy of Sciences (India)

    Adsorption isotherms were obtained and desulphurization kinetics were carried out on solutions of dibenzothiophene (DBT) and thiophene in a model fuel. The efficiencies of DBT and thiophene removal were reported. The adsorption isotherms fitted the Langmuir and Freundlich models. The highest adsorption capacity for ...

  18. Integrated Microfluidic Nucleic Acid Isolation, Isothermal Amplification, and Amplicon Quantification

    Science.gov (United States)

    Mauk, Michael G.; Liu, Changchun; Song, Jinzhao; Bau, Haim H.

    2015-01-01

    Microfluidic components and systems for rapid (nucleic acids (NAs) are extracted from relatively large (~mL) volume sample lysates using an embedded porous silica glass fiber or cellulose binding phase (“membrane”) to capture sample NAs in a flow-through, filtration mode; (2) NAs captured on the membrane are isothermally (~65 °C) amplified; (3) amplicon production is monitored by real-time fluorescence detection, such as with a smartphone CCD camera serving as a low-cost detector; and (4) paraffin-encapsulated, lyophilized reagents for temperature-activated release are pre-stored in the chip. Limits of Detection (LOD) better than 103 virons/sample can be achieved. A modified chip with conduits hosting a diffusion-mode amplification process provides a simple visual indicator to readily quantify sample NA template. In addition, a companion microfluidic device for extracting plasma from whole blood without a centrifuge, generating cell-free plasma for chip-based molecular diagnostics, is described. Extensions to a myriad of related applications including, for example, food testing, cancer screening, and insect genotyping are briefly surveyed. PMID:27600235

  19. The analysis of isotherms of radionuclides sorption by inorganic sorbents

    Science.gov (United States)

    Bykova, E. P.; Nedobukh, T. A.

    2017-09-01

    The isotherm of cesium sorption by an inorganic sorbent based on granulated glauconite obtained in a wide cesium concentrations range was mathematically treated using Langmuir, Freundlich and Redlich-Peterson sorption models. The algorithms of mathematical treatment of experimental data using these models were described; parameters of all isotherms were determined. It was shown that estimating the correctness of various sorption models relies not only on the correlation coefficient values but also on the closeness of the calculated and experimental data. Various types of sorption sites were found as a result of mathematical treatment of the isotherm of cesium sorption. The algorithm was described and calculation of parameters of the isotherm was performed under the assumption that simultaneous sorption on all three types of sorption sites occurs in accordance with Langmuir isotherm.

  20. Isothermal martensite formation at sub-zero temperatures

    DEFF Research Database (Denmark)

    Stojko, Allan; Hansen, Mikkel Fougt; Slycke, Jan

    2011-01-01

    Sub-zero treatment of steels with an M1 below 0°C relies (partly) on a continuation of the martensite formation. The present work reports on the observation of isothermal martensite formation in the sub-zero temperature regime for two steels: AISI 1070 and AISI 52100. Samples were austenitized......, quenched in oil, and thereafter investigated with vibrating sample magnetometry, which allows a quantitative assessment of the fraction of retained austenite as a function of the sub-zero temperature and time. Isothermal martensite formation was observed on interrupting the continuous cooling (5 K....../min) at temperatures in the range of 80-233 K. The kinetics of isothermal martensite formation depends strongly on the temperature and can be described by Johnson-Mehl-Avrami-Kolmogorov kinetics. Isothermal experiments with dilatometry indicated the occurrence of a volume increase on isothermal holding, consistent...

  1. Modeling and Prediction of Soil Water Vapor Sorption Isotherms

    DEFF Research Database (Denmark)

    Arthur, Emmanuel; Tuller, Markus; Moldrup, Per

    2015-01-01

    Soil water vapor sorption isotherms describe the relationship between water activity (aw) and moisture content along adsorption and desorption paths. The isotherms are important for modeling numerous soil processes and are also used to estimate several soil (specific surface area, clay content......, cation exchange capacity) and engineering properties (e.g., swelling potential). Our objectives for this work were to: (i) evaluate the potential of several theoretical and empirical isotherm models to accurately describe measured moisture adsorption/desorption isotherms (aw range of 0.03 to 0.......93) for a wide range of soils; and (ii) develop and test regression models for estimating the isotherms from clay content. Preliminary results show reasonable fits of the majority of the investigated empirical and theoretical models to the measured data although some models were not capable to fit both sorption...

  2. Electrical transport and current properties of rare-earth dysprosium Schottky electrode on p-type GaN at various annealing temperatures

    Science.gov (United States)

    Nagaraju, G.; Ravindranatha Reddy, K.; Rajagopal Reddy, V.

    2017-11-01

    The electrical and current transport properties of rapidly annealed Dy/p-GaN SBD are probed by I–V and C–V techniques. The estimated barrier heights (BH) of as-deposited and 200 °C annealed SBDs are 0.80 eV ( I–V)/0.93 eV (C–V) and 0.87 eV (I–V)/1.03 eV (C–V). However, the BH rises to 0.99 eV (I–V)/ 1.18 eV(C–V) and then slightly deceases to 0.92 eV (I–V)/1.03 eV (C–V) after annealing at 300 °C and 400 °C. The utmost BH is attained after annealing at 300 °C and thus the optimum annealing for SBD is 300 °C. By applying Cheung’s functions, the series resistance of the SBD is estimated. The BHs estimated by I–V, Cheung’s and Ψ S–V plot are closely matched; hence the techniques used here are consistency and validity. The interface state density of the as-deposited and annealed contacts are calculated and we found that the N SS decreases up to 300 °C annealing and then slightly increases after annealing at 400 °C. Analysis indicates that ohmic and space charge limited conduction mechanisms are found at low and higher voltages in forward-bias irrespective of annealing temperatures. Our experimental results demonstrate that the Poole–Frenkel emission is leading under the reverse bias of Dy/p-GaN SBD at all annealing temperatures.

  3. Binary Sparse Phase Retrieval via Simulated Annealing

    Directory of Open Access Journals (Sweden)

    Wei Peng

    2016-01-01

    Full Text Available This paper presents the Simulated Annealing Sparse PhAse Recovery (SASPAR algorithm for reconstructing sparse binary signals from their phaseless magnitudes of the Fourier transform. The greedy strategy version is also proposed for a comparison, which is a parameter-free algorithm. Sufficient numeric simulations indicate that our method is quite effective and suggest the binary model is robust. The SASPAR algorithm seems competitive to the existing methods for its efficiency and high recovery rate even with fewer Fourier measurements.

  4. Fourier-transforming with quantum annealers

    Directory of Open Access Journals (Sweden)

    Itay eHen

    2014-07-01

    Full Text Available We introduce a set of quantum adiabatic evolutions that we argue may be used as `building blocks', or subroutines, in the onstruction of an adiabatic algorithm that executes Quantum Fourier Transform (QFT with the same complexity and resources as its gate-model counterpart. One implication of the above construction is the theoretical feasibility of implementing Shor's algorithm for integer factorization in an optimal manner, and any other algorithm that makes use of QFT, on quantum annealing devices. We discuss the possible advantages, as well as the limitations, of the proposed approach as well as its relation to traditional adiabatic quantum computation.

  5. Preparation and Thermal Characterization of Annealed Gold Coated Porous Silicon

    Directory of Open Access Journals (Sweden)

    Afarin Bahrami

    2012-01-01

    Full Text Available Porous silicon (PSi layers were formed on a p-type Si wafer. Six samples were anodised electrically with a 30 mA/cm2 fixed current density for different etching times. The samples were coated with a 50–60 nm gold layer and annealed at different temperatures under Ar flow. The morphology of the layers, before and after annealing, formed by this method was investigated by scanning electron microscopy (SEM. Photoacoustic spectroscopy (PAS measurements were carried out to measure the thermal diffusivity (TD of the PSi and Au/PSi samples. For the Au/PSi samples, the thermal diffusivity was measured before and after annealing to study the effect of annealing. Also to study the aging effect, a comparison was made between freshly annealed samples and samples 30 days after annealing.

  6. Annealing furnace for III-V semiconductor devices

    Science.gov (United States)

    O'Connor, J. M.; Hier, H. S.; Ketchum, R. M.

    1986-02-01

    A furnace for annealing ion implantation damage in III-V semiconductors has been built and tested. Designed for research applications, the furnace can accommodate odd shapes of material up to 2 in. in diameter. Samples are loaded onto a novel cantilevered support and are not moved during the annealing operation, facilitating proximity annealing techniques. Both chambers of this dual chambered system are O-ring sealed for added safety during annealing in an arsine gas ambient. Electron mobilities between 4400 and 4600 cm2/V s at 300 K are routinely measured for 2×1017 cm-3 gallium arsenide material annealed in this sytem. The system has been used to anneal indium phosphide as well as gallium arsenide wafers.

  7. A "release" protocol for isothermal titration calorimetry.

    Science.gov (United States)

    Heerklotz, H H; Binder, H; Epand, R M

    1999-05-01

    Isothermal titration calorimetry (ITC) has become a standard method for investigating the binding of ligands to receptor molecules or the partitioning of solutes between water and lipid vesicles. Accordingly, solutes are mixed with membranes (or ligands with receptors), and the subsequent heats of incorporation (or binding) are measured. In this paper we derive a general formula for modeling ITC titration heats in both binding and partitioning systems that allows for the modeling of the classic incorporation or binding protocols, as well as of new protocols assessing the release of solute from previously solute-loaded vesicles (or the dissociation of ligand/receptor complexes) upon dilution. One major advantage of a simultaneous application of the incorporation/binding and release protocols is that it allows for the determination of whether a ligand is able to access the vesicle interior within the time scale of the ITC experiment. This information cannot be obtained from a classical partitioning experiment, but it must be known to determine the partition coefficient (or binding constant and stochiometry) and the transfer enthalpy. The approach is presented using the partitioning of the nonionic detergent C12EO7 to palmitoyloleoylphosphatidylcholine vesicles. The release protocol could also be advantageous in the case of receptors that are more stable in the ligand-saturated rather than the ligand-depleted state.

  8. Sorption isotherm characteristics of aonla flakes.

    Science.gov (United States)

    Alam, Md Shafiq; Singh, Amarjit

    2011-06-01

    The equilibrium moisture content was determined for un-osmosed and osmosed (salt osmosed and sugar osmosed) aonla flakes using the static method at temperatures of 25, 40,50, 60 and 70 °C over a range of relative humidities from 20 to 90%. The sorption capacity of aonla decreased with an increase in temperature at constant water activity. The sorption isotherms exhibited hysteresis, in which the equilibrium moisture content was higher at a particular equilibrium relative humidity for desorption curve than for adsorption. The hysteresis effect was more pertinent for un-osmosed and salt osmosed samples in comparison to sugar osmosed samples. Five models namely the modified Chung Pfost, modified Halsey, modified Henderson, modified Exponential and Guggenheim-Anderson-de Boer (GAB) were evaluated to determine the best fit for the experimental data. For both adsorption and desorption process of aonla fruit, the equilibrium moisture content of un-osmosed and osmosed aonla samples can be predicted well by GAB model as well as modified Exponential model. Moreover, the modified Exponential model was found to be the best for describing the sorption behaviour of un-osmosed and salt osmosed samples while, GAB model for sugar osmosed aonla samples.

  9. Optimal Move Class For Simulated Annealing With Underlying Optimal Schedule

    OpenAIRE

    Hartwig, Ines

    2009-01-01

    Die vorliegende Arbeit befasst sich mit dem Versuch der Optimierung von Simulated Annealing. Genauer gesagt, werden Simulationsergebnisse für einfache Spinglassysteme in Abhängigkeit von verschiedenen Nachbarschaftsmodellen berechnet – jeweils unter Verwendung des optimalen Abkühlverlaufs. Ziel ist es, eine Faustregel für die dynamische Anpassung der Nachbarschaftsbeziehung während einer Annealing-Simulation zu finden. The thesis at hand presents an attempt to optimize simulated annealing. ...

  10. Combining isothermal rolling circle amplification and electrochemiluminescence for highly sensitive point mutation detection

    Science.gov (United States)

    Su, Qiang; Zhou, Xiaoming

    2008-12-01

    Many pathogenic and genetic diseases are associated with changes in the sequence of particular genes. We describe here a rapid and highly efficient assay for the detection of point mutation. This method is a combination of isothermal rolling circle amplification (RCA) and high sensitive electrochemluminescence (ECL) detection. In the design, a circular template generated by ligation upon the recognition of a point mutation on DNA targets was amplified isothermally by the Phi29 polymerase using a biotinylated primer. The elongation products were hybridized with tris (bipyridine) ruthenium (TBR)-tagged probes and detected in a magnetic bead based ECL platform, indicating the mutation occurrence. P53 was chosen as a model for the identification of this method. The method allowed sensitive determination of the P53 mutation from wild-type and mutant samples. The main advantage of RCA-ECL is that it can be performed under isothermal conditions and avoids the generation of false-positive results. Furthermore, ECL provides a faster, more sensitive, and economical option to currently available electrophoresis-based methods.

  11. Error-corrected quantum annealing with hundreds of qubits

    National Research Council Canada - National Science Library

    Pudenz, Kristen L; Albash, Tameem; Lidar, Daniel A

    2014-01-01

    .... So far, little is known about protection against decoherence for quantum annealing, a computational paradigm aiming to exploit ground-state quantum dynamics to solve optimization problems more...

  12. Annealing effects on deuterium retention behavior in damaged tungsten

    Directory of Open Access Journals (Sweden)

    S. Sakurada

    2016-12-01

    Full Text Available Effects of annealing after/under iron (Fe ion irradiation on deuterium (D retention behavior in tungsten (W were studied. The D2 TDS spectra as a function of heating temperature for 0.1dpa damaged W showed that the D retention was clearly decreased as the annealing temperature was increased. In particular, the desorption of D trapped by voids was largely reduced by annealing at 1173K. The TEM observation indicated that the size of dislocation loops was clearly grown, and its density was decreased by the annealing above 573K. After annealing at 1173K, almost all the dislocation loops were recovered. The results of positron annihilation spectroscopy suggested that the density of vacancy-type defects such as voids, was decreased as the annealing temperature was increased, while its size was increased, indicating that the D retention was reduced by the recovery of the voids. Furthermore, it was found that the desorption temperature of D trapped by the voids for damaged W above 0.3dpa was shifted toward higher temperature side. These results lead to a conclusion that the D retention behavior is controlled by defect density. The D retention in the samples annealed during irradiation was less than that annealed after irradiation. This result shows that defects would be quickly annihilated before stabilization by annealing during irradiation.

  13. Phase field modeling of dendritic coarsening during isothermal

    Directory of Open Access Journals (Sweden)

    Zhang Yutuo

    2011-08-01

    Full Text Available Dendritic coarsening in Al-2mol%Si alloy during isothermal solidification at 880K was investigated by phase field modeling. Three coarsening mechanisms operate in the alloy: (a melting of small dendrite arms; (b coalescence of dendrites near the tips leading to the entrapment of liquid droplets; (c smoothing of dendrites. Dendrite melting is found to be dominant in the stage of dendritic growth, whereas coalescence of dendrites and smoothing of dendrites are dominant during isothermal holding. The simulated results provide a better understanding of dendrite coarsening during isothermal solidification.

  14. Total Correlation Function Integrals and Isothermal Compressibilities from Molecular Simulations

    DEFF Research Database (Denmark)

    Wedberg, Rasmus; Peters, Günther H.j.; Abildskov, Jens

    2008-01-01

    Generation of thermodynamic data, here compressed liquid density and isothermal compressibility data, using molecular dynamics simulations is investigated. Five normal alkane systems are simulated at three different state points. We compare two main approaches to isothermal compressibilities: (1...... in approximately the same amount of time. This suggests that computation of total correlation function integrals is a route to isothermal compressibility, as accurate and fast as well-established benchmark techniques. A crucial step is the integration of the radial distribution function. To obtain sensible results...

  15. MEDICAL STAFF SCHEDULING USING SIMULATED ANNEALING

    Directory of Open Access Journals (Sweden)

    Ladislav Rosocha

    2015-07-01

    Full Text Available Purpose: The efficiency of medical staff is a fundamental feature of healthcare facilities quality. Therefore the better implementation of their preferences into the scheduling problem might not only rise the work-life balance of doctors and nurses, but also may result into better patient care. This paper focuses on optimization of medical staff preferences considering the scheduling problem.Methodology/Approach: We propose a medical staff scheduling algorithm based on simulated annealing, a well-known method from statistical thermodynamics. We define hard constraints, which are linked to legal and working regulations, and minimize the violations of soft constraints, which are related to the quality of work, psychic, and work-life balance of staff.Findings: On a sample of 60 physicians and nurses from gynecology department we generated monthly schedules and optimized their preferences in terms of soft constraints. Our results indicate that the final value of objective function optimized by proposed algorithm is more than 18-times better in violations of soft constraints than initially generated random schedule that satisfied hard constraints.Research Limitation/implication: Even though the global optimality of final outcome is not guaranteed, desirable solutionwas obtained in reasonable time. Originality/Value of paper: We show that designed algorithm is able to successfully generate schedules regarding hard and soft constraints. Moreover, presented method is significantly faster than standard schedule generation and is able to effectively reschedule due to the local neighborhood search characteristics of simulated annealing.

  16. Magnetic field annealing for improved creep resistance

    Energy Technology Data Exchange (ETDEWEB)

    Brady, Michael P.; Ludtka, Gail M.; Ludtka, Gerard M.; Muralidharan, Govindarajan; Nicholson, Don M.; Rios, Orlando; Yamamoto, Yukinori

    2015-12-22

    The method provides heat-resistant chromia- or alumina-forming Fe-, Fe(Ni), Ni(Fe), or Ni-based alloys having improved creep resistance. A precursor is provided containing preselected constituents of a chromia- or alumina-forming Fe-, Fe(Ni), Ni(Fe), or Ni-based alloy, at least one of the constituents for forming a nanoscale precipitate MaXb where M is Cr, Nb, Ti, V, Zr, or Hf, individually and in combination, and X is C, N, O, B, individually and in combination, a=1 to 23 and b=1 to 6. The precursor is annealed at a temperature of 1000-1500.degree. C. for 1-48 h in the presence of a magnetic field of at least 5 Tesla to enhance supersaturation of the M.sub.aX.sub.b constituents in the annealed precursor. This forms nanoscale M.sub.aX.sub.b precipitates for improved creep resistance when the alloy is used at service temperatures of 500-1000.degree. C. Alloys having improved creep resistance are also disclosed.

  17. Superplasticity of Annealed H13 Steel.

    Science.gov (United States)

    Duan, Zhenxin; Pei, Wen; Gong, Xuebo; Chen, Hua

    2017-07-28

    H13 steel is a widely used hot work die material. A new type of hot working method is imperative to develop complex and precise dies. In this paper, the heat treatment of H13 steel (AISI) was carried out by annealing, the final structure is a point or spherical pearlite, and the grain size is about 30-40 μm. The tensile properties of the annealed microstructure were investigated at 650, 750, and 850 °C with the strain rates of 1 × 10(-3) s(-1), 5 × 10(-4) s(-1), and 1 × 10(-4) s(-1). The tensile fracture and microstructure were analyzed by SEM and HREM. The results show that the tensile samples reach superplasticity at the strain rate of 1 × 10(-4) s(-1) in the temperature range of 750-850 °C. When the temperature is 850 °C, the maximum elongation rate reaches 112.5%. This demonstrates the possibility of making superplastic forming molds. During the tensile process, the refined M23C₆ and other high hardness carbides which are dispersed uniformly in the matrix, effectively inhibits grain growth and hinders dislocation movement, leading to the improvement of plasticity.

  18. A coherent quantum annealer with Rydberg atoms

    Science.gov (United States)

    Glaetzle, A. W.; van Bijnen, R. M. W.; Zoller, P.; Lechner, W.

    2017-06-01

    There is a significant ongoing effort in realizing quantum annealing with different physical platforms. The challenge is to achieve a fully programmable quantum device featuring coherent adiabatic quantum dynamics. Here we show that combining the well-developed quantum simulation toolbox for Rydberg atoms with the recently proposed Lechner-Hauke-Zoller (LHZ) architecture allows one to build a prototype for a coherent adiabatic quantum computer with all-to-all Ising interactions and, therefore, a platform for quantum annealing. In LHZ an infinite-range spin-glass is mapped onto the low energy subspace of a spin-1/2 lattice gauge model with quasi-local four-body parity constraints. This spin model can be emulated in a natural way with Rubidium and Caesium atoms in a bipartite optical lattice involving laser-dressed Rydberg-Rydberg interactions, which are several orders of magnitude larger than the relevant decoherence rates. This makes the exploration of coherent quantum enhanced optimization protocols accessible with state-of-the-art atomic physics experiments.

  19. Effect of annealing temperature on magnetic property of Si{sub 1-x}Cr{sub x} thin films

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Wenyong; Guo Liping, E-mail: guolp@whu.edu.cn; Peng Guoliang; Li Tiecheng; Feng Shixuan; Zhou Zhongpo; Peng Ting; Quan Zuci

    2011-11-01

    Polycrystalline Si{sub 1-x}Cr{sub x} thin films have been prepared by magnetron sputtering followed by rapid thermal annealing (RTA) for crystallization. RTA was performed at 800 Degree-Sign C for 5 min, 1200 Degree-Sign C for 30 s and 1200 Degree-Sign C for 2 min, in a N{sub 2} flow. The magnetic hysteresis loops were observed at room temperature in all the samples except for RTA at 800 Degree-Sign C for 5 min, and the annealing caused the decrease of saturation magnetization relative to the as-grown film. X-ray diffraction spectra and Raman spectra showed that the annealing process lead the deposited amorphous film to be crystallized and CrSi{sub 2} phase formed. The magnetism of the films was determined by the competition between crystallinity and precipitation of diamagnetic CrSi{sub 2} phase.

  20. Fabrication of Ohmic contact on semi-insulating 4H-SiC substrate by laser thermal annealing

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, Yue; Lu, Wu-yue; Wang, Tao; Chen, Zhi-zhan, E-mail: zzchen@shnu.edu.cn [Department of Physics, Shanghai Normal University, 100 Guilin Road, Shanghai 200234 (China)

    2016-06-14

    The Ni contact layer was deposited on semi-insulating 4H-SiC substrate by magnetron sputtering. The as-deposited samples were treated by rapid thermal annealing (RTA) and KrF excimer laser thermal annealing (LTA), respectively. The RTA annealed sample is rectifying while the LTA sample is Ohmic. The specific contact resistance (ρ{sub c}) is 1.97 × 10{sup −3} Ω·cm{sup 2}, which was determined by the circular transmission line model. High resolution transmission electron microscopy morphologies and selected area electron diffraction patterns demonstrate that the 3C-SiC transition zone is formed in the near-interface region of the SiC after the as-deposited sample is treated by LTA, which is responsible for the Ohmic contact formation in the semi-insulating 4H-SiC.

  1. Endpoint Visual Detection of Three Genetically Modified Rice Events by Loop-Mediated Isothermal Amplification

    Directory of Open Access Journals (Sweden)

    Qing Zhu

    2012-11-01

    Full Text Available Genetically modified (GM rice KMD1, TT51-1, and KF6 are three of the most well known transgenic Bt rice lines in China. A rapid and sensitive molecular assay for risk assessment of GM rice is needed. Polymerase chain reaction (PCR, currently the most common method for detecting genetically modified organisms, requires temperature cycling and relatively complex procedures. Here we developed a visual and rapid loop-mediated isothermal amplification (LAMP method to amplify three GM rice event-specific junction sequences. Target DNA was amplified and visualized by two indicators (SYBR green or hydroxy naphthol blue [HNB] within 60 min at an isothermal temperature of 63 °C. Different kinds of plants were selected to ensure the specificity of detection and the results of the non-target samples were negative, indicating that the primer sets for the three GM rice varieties had good levels of specificity. The sensitivity of LAMP, with detection limits at low concentration levels (0.01%–0.005% GM, was 10- to 100-fold greater than that of conventional PCR. Additionally, the LAMP assay coupled with an indicator (SYBR green or HNB facilitated analysis. These findings revealed that the rapid detection method was suitable as a simple field-based test to determine the status of GM crops.

  2. Annealing-induced interfacial atomic intermixing in InAs/GaSb type II superlattices

    Science.gov (United States)

    Li, Xiaochao; Zhang, Yong; Jiang, Dongwei; Guo, Fengyun; Zhao, Liancheng

    2017-10-01

    We have investigated the effect of post-growth rapid thermal annealing (RTA) on the interface structure and atomic intermixing of InAs/GaSb type II superlattices (T2SLs). It is found that the mechanism of interfacial atomic interdiffusion of the anion (In/Ga) and the cation (As/Sb) is different. The activation energies of 0.62 eV and 0.27 eV are calculated to describe the In/Ga and As/Sb interdiffusion. In T2SLs, RTA will promote As/Sb intermixing across the interfaces between 450 and 480 °C, while In/Ga intermixing will be activated at 500 °C annealing. This demonstrates that the appropriate In/Ga intermixing is important to control the deterioration of the interfacial quality and the formation of dislocations, which is very crucial for the device performance.

  3. Inkjet-Printed In-Ga-Zn Oxide Thin-Film Transistors with Laser Spike Annealing

    Science.gov (United States)

    Huang, Hang; Hu, Hailong; Zhu, Jingguang; Guo, Tailiang

    2017-07-01

    Inkjet-printed In-Ga-Zn oxide (IGZO) thin-film transistors (TFTs) have been fabricated at low temperature using laser spike annealing (LSA) treatment. Coffee-ring effects during the printing process were eliminated to form uniform IGZO films by simply increasing the concentration of solute in the ink. The impact of LSA on the TFT performance was studied. The field-effect mobility, threshold voltage, and on/off current ratio were greatly influenced by the LSA treatment. With laser scanning at 1 mm/s for 40 times, the 30-nm-thick IGZO TFT baked at 200°C showed mobility of 1.5 cm2/V s, threshold voltage of -8.5 V, and on/off current ratio >106. Our findings demonstrate the feasibility of rapid LSA treatment of low-temperature inkjet-printed oxide semiconductor transistors, being comparable to those obtained by conventional high-temperature annealing.

  4. Ideal Adsorption Isotherm Behavior for Cooling Applications.

    Science.gov (United States)

    Bagheri, Morteza H; Schiffres, Scott N

    2018-01-24

    Purely heat-driven refrigeration has the potential for high primary-energy efficiency, especially when powered by waste heat or solar thermal sources. This paper presents a novel expression for the ideal adsorption step location as a function of operating conditions. This methodology is then applied to a hypothetical stepwise material to evaluate its intrinsic efficiency. This analysis technique is then extended to allow facile efficiency comparisons for any adsorbent-refrigerant pair using an adsorbent's isotherm and heat of adsorption properties. This work focuses on limitations to efficiency due to the equilibrium thermodynamics. It is found that a stepwise adsorbent can have a single-effect intrinsic efficiency of as high as about 85% of Carnot, assuming typical adsorbent specific heats and uptake capacity. Using these tools, we analyze the maximum ratio of cooling to heat input (coefficient of performance) for two adsorption pairs, zeolite 13X-water and UiO-66-water, which are found to have maximum coefficients of performance of 0.52 and 0.88 for a cold-side temperature of 10 °C and an ambient temperature of 30 °C, respectively. Meanwhile, the maximum fraction of Carnot cooling is 37% for zeolite 13X-water and 67% for UiO-66-water. Moreover, these peak fractions of Carnot occur at much higher regeneration temperatures for 13X (196 °C) than for UiO-66 (60 °C). These two materials could be coupled in a two-stage cascading triple-effect adsorption cycle that operates with a combined coefficient of performance of 1.50 at a regeneration temperature of 196 °C, a cold-side temperature of 10 °C, and an ambient temperature of 30 °C.

  5. Annealing effects and DLTS study on PNP silicon bipolar junction transistors irradiated by 20 MeV Br ions

    Science.gov (United States)

    Liu, Chaoming; Li, Xingji; Yang, Jianqun; Bollmann, Joachim

    2014-01-01

    Isochronal anneal sequences have been carried out on 3CG130 silicon PNP bipolar junction transistors (BJTs) irradiated with 20 MeV bromine (Br) heavy ions. The Gummel curve was utilized to characterize the annealing behavior of defects in both the emitter-base depletion region and the neutral base. The results show that the base current (IB) decreases with the increasing annealing temperature, while the collector current (IC) keeps invariably. The current gain varies slightly, when the annealing temperature (TA) is lower than 500 K, while varies rapidly at TA>550 K, and the current gain of the 3CG130 BJT annealing at 700 K almost restore to that of the pre-radiation transistor. The deep level transient spectroscopy (DLTS) data was used to assign the relative magnitude of each of the important defects. Based on the in situ electrical measurement and DLTS spectra, it is clear that the V2(+/0) trap is the main contribution to the degradation of current gain after the 20 MeV Br ions irradiation. The V2(+/0) peak has many characteristics expected for the current gain degradation.

  6. Annealing effects and DLTS study on PNP silicon bipolar junction transistors irradiated by 20 MeV Br ions

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Chaoming [School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001 (China); Li, Xingji, E-mail: lxj0218@hit.edu.cn [School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001 (China); Yang, Jianqun [School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001 (China); Bollmann, Joachim [Institute of Electronics and Sensor Materials, TU Bergakademie, Freiberg 71691 (Germany)

    2014-01-21

    Isochronal anneal sequences have been carried out on 3CG130 silicon PNP bipolar junction transistors (BJTs) irradiated with 20 MeV bromine (Br) heavy ions. The Gummel curve was utilized to characterize the annealing behavior of defects in both the emitter-base depletion region and the neutral base. The results show that the base current (I{sub B}) decreases with the increasing annealing temperature, while the collector current (I{sub C}) keeps invariably. The current gain varies slightly, when the annealing temperature (T{sub A}) is lower than 500 K, while varies rapidly at T{sub A}>550 K, and the current gain of the 3CG130 BJT annealing at 700 K almost restore to that of the pre-radiation transistor. The deep level transient spectroscopy (DLTS) data was used to assign the relative magnitude of each of the important defects. Based on the in situ electrical measurement and DLTS spectra, it is clear that the V{sub 2}(+/0) trap is the main contribution to the degradation of current gain after the 20 MeV Br ions irradiation. The V{sub 2}(+/0) peak has many characteristics expected for the current gain degradation.

  7. Improved Isotherm Data for Adsorption of Methane on Activated Carbons

    KAUST Repository

    Loh, Wai Soong

    2010-08-12

    This article presents the adsorption isotherms of methane onto two different types of activated carbons, namely, Maxsorb III and ACF (A-20) at temperatures from (5 to 75) °C and pressures up to 2.5 MPa. The volumetric technique has been employed to measure the adsorption isotherms. The experimental results presented herein demonstrate the improved accuracy of the uptake values compared with previous measurement techniques for similar adsorbate-adsorbent combinations. The results are analyzed with various adsorption isotherm models. The heat of adsorption, which is concentration and temperature dependent, has been calculated from the measured isotherm data. Henry\\'s law coefficients for these adsorbent-methane pairs are also evaluated at various temperatures. © 2010 American Chemical Society.

  8. Non-isothermal crystallization kinetics of polyethylene–clay ...

    Indian Academy of Sciences (India)

    MDPE) and MDPE–clay nanocomposites have been investigated by differential scanning calorimeter. The modified Avrami, Ozawa, Liu and Ziabicki equations have been applied to describe non-isothermal crystallization process. The results of ...

  9. Isothermal martensite formation at sub-zero temperatures

    DEFF Research Database (Denmark)

    Stojko, Allan; Hansen, Mikkel Fougt; Slycke, Jan

    2010-01-01

    Sub-zero treatment of steels with an Mf below zero degrees Celsius relies (partly) on a continuation of the martensite formation. The present work reports on the observation of isothermal martensite formation in the sub-zero temperature regime for two steels: AISI 1070 and AISI 52100. Samples were...... austenitized and quenched in oil and thereafter investigated with vibrating sample agnetometry, which allows a quantitative assessment of the fraction of retained austenite as a function of the subzero temperature and time. Isothermal martensite formation was observed on interrupting the continuous cooling (5...... with a continuation of the martensitic transformation. On prolonged isothermal holding a volume reduction was observed for AISI 52100, but not for AISI 1070. A mechanism is proposed that explains the occurrence of isothermal martensite formation....

  10. Determination of Differential Enthalpy and Isotherm by Adsorption Calorimetry

    OpenAIRE

    Garcia-Cuello, V.; Moreno-Piraján, J. C; Giraldo-Gutiérrez, L.; K. Sapag; Zgrablich, G.

    2008-01-01

    An adsorption microcalorimeter for the simultaneous determination of the differential heat of adsorption and the adsorption isotherm for gas-solid systems are designed, built, and tested. For this purpose, a Calvet heat-conducting microcalorimeter is developed and is connected to a gas volumetric unit built in stainless steel to record adsorption isotherms. The microcalorimeter is electrically calibrated to establish its sensitivity and reproducibility, obtaining K=154.34±0.23 WV−1. The adsor...

  11. Simple isotherm equations to fit type I adsorption data

    OpenAIRE

    Mosquera, Martin A.

    2009-01-01

    A simple model to fit experimental data of adsorption of gases and vapours on microporous adsorbents (type I isotherms) is proposed. The main assumption is that the adsorbate phase can be divided into identical and non-interacting effective subsystems. This gives rise to a simple multiparametric isotherm based on the grand canonical ensemble statistics, whose functional form is a ratio of two polynomial functions. The parameters are interpreted as effective equilibrium constants. A simplified...

  12. Karakteristik Kurva Isotherm Sorpsi Air Tepung Jagung Instan

    OpenAIRE

    Nur Aini; Vicentius Prihananto; Gunawan Wijonarko

    2014-01-01

    Instantiation of flour was expected to affect the equilibrium moisture content which changes the nature of the product. Instant corn flour as raw material of semi-moist foods should be determined of its equilibrium moisture content using the curve of moisture sorption isotherm. Curves of moisture sorption isotherm plays an important role in food drying system, particularly for predicting the shelf life of foods that have low water content. The research was aimed to obtain moisture...

  13. Karakteristik Kurva Isotherm Sorpsi Air Tepung Jagung Instan

    OpenAIRE

    Aini, Nur; Prihananto, Vicentius; Wijonarko, Gunawan

    2014-01-01

    Instantiation of flour was expected to affect the equilibrium moisture content which changes the nature of the product. Instant corn flour as raw material of semi-moist foods should be determined of its equilibrium moisture content using the curve of moisture sorption isotherm. Curves of moisture sorption isotherm plays an important role in food drying system, particularly for predicting the shelf life of foods that have low water content. The research was aimed to obtain moisture sorption is...

  14. Isothermal Roll Forging of T55 Compressor Blades. Phase 2

    Science.gov (United States)

    1980-06-01

    Roll-Forging From 0.375 Inch Ti6Al4V to 7 Simulated Mid-Span Shrouded Blade in One Pass 5 Comparison of Airfoil Edge Finishing Operations 9 6...Isothermal Rolled Ti6Al4V Bar (single pass) (#74-20001 Figure 4. Isothermal Roll-Forging From 0.375 Inch Ti6A14V to Simulated Mid

  15. Isothermal Calorimetry for Biological Applications in Food Science and Technology

    OpenAIRE

    Wadsö, Lars; Gomez, Federico

    2009-01-01

    All physical, chemical and biological processes produce heat and isothermal calorimetry is a general measurement technique to study all kinds of processes by the heat they produce. This paper gives several examples of studies of biological processes in the food area using isothermal calorimetry. It is for example shown how different unit operations influence respiration of vegetable tissue, how the kinetics of a fermentation process can be studied, and how spoilage processes can be followed f...

  16. Characterization of β-lactamase activity using isothermal titration calorimetry.

    Science.gov (United States)

    Wang, Wen-Jing; Wang, Qian; Zhang, Ye; Lu, Rui; Zhang, Yi-Lin; Yang, Ke-Wu; Lei, Jin-E; He, Yuan

    2017-08-01

    Hydrolysis of β-lactam antibiotic by β-lactamase is the most common mechanism of β-lactam resistance in clinical isolates. Timely detection and characterization of β-lactamases are therefore of utmost biomedical importance. Conventional spectrophotometric method is time-consuming and cannot provide thermodynamic information on β-lactamases. A new assay was developed for the study of β-lactamase activity in protein solutions (Metallo-β-lactamase L1) and in clinical bacterial cells, based on heat-flow changes derived from enzymatic hydrolysis of β-lactams using isothermal titration calorimetry. (1) The thermokinetic parameters of three antibiotics (penicillin G, cefazolin and imipenem) and the inhibition constant of an azolylthioacetamide inhibitor were determined using the calorimetric assay. The results from the calorimetric assays were consistent with the data from the spectrophotometric assay. (2) The values of heat change in the calorimetric assay using two clinical Escherichia coli strains correlated well with their antibiotic susceptibility results from the broth dilution experiment. The subtypes of β-lactamase were also determined in the calorimetric assay. The ITC assay is a reliable and fast method to study β-lactamase enzyme kinetics and inhibition. It can also provide thermodynamic information on antibiotic hydrolysis, which has been taken advantage of in this work to study β-lactamase activity in two clinical Escherichia coli isolates. As the first calorimetric study of β-lactamase activity, it may provide a new assay to assist biomedical validation of new β-lactamase inhibitors, and also has potential applications on rapid antibiotic susceptibility testing and screening β-lactamase producing bacteria. Copyright © 2017. Published by Elsevier B.V.

  17. Integrated Microfluidic Nucleic Acid Isolation, Isothermal Amplification, and Amplicon Quantification

    Directory of Open Access Journals (Sweden)

    Michael G. Mauk

    2015-10-01

    Full Text Available Microfluidic components and systems for rapid (<60 min, low-cost, convenient, field-deployable sequence-specific nucleic acid-based amplification tests (NAATs are described. A microfluidic point-of-care (POC diagnostics test to quantify HIV viral load from blood samples serves as a representative and instructive example to discuss the technical issues and capabilities of “lab on a chip” NAAT devices. A portable, miniaturized POC NAAT with performance comparable to conventional PCR (polymerase-chain reaction-based tests in clinical laboratories can be realized with a disposable, palm-sized, plastic microfluidic chip in which: (1 nucleic acids (NAs are extracted from relatively large (~mL volume sample lysates using an embedded porous silica glass fiber or cellulose binding phase (“membrane” to capture sample NAs in a flow-through, filtration mode; (2 NAs captured on the membrane are isothermally (~65 °C amplified; (3 amplicon production is monitored by real-time fluorescence detection, such as with a smartphone CCD camera serving as a low-cost detector; and (4 paraffin-encapsulated, lyophilized reagents for temperature-activated release are pre-stored in the chip. Limits of Detection (LOD better than 103 virons/sample can be achieved. A modified chip with conduits hosting a diffusion-mode amplification process provides a simple visual indicator to readily quantify sample NA template. In addition, a companion microfluidic device for extracting plasma from whole blood without a centrifuge, generating cell-free plasma for chip-based molecular diagnostics, is described. Extensions to a myriad of related applications including, for example, food testing, cancer screening, and insect genotyping are briefly surveyed.

  18. An Isothermal Steam Expander for an Industrial Steam Supplying System

    Directory of Open Access Journals (Sweden)

    Chen-Kuang Lin

    2015-01-01

    Full Text Available Steam is an essential medium used in the industrial process. To ensure steam quality, small and middle scale boilers are often adopted. However, because a higher steam pressure (compared to the necessary steam pressure is generated, the boiler’s steam pressure will be reduced via a pressure regulator before the steam is directed through the process. Unfortunately, pressure is somewhat wasted during the reducing process. Therefore, in order to promote energy efficiency, a pressure regulator is replaced by a steam expander. With this steam expander, the pressure will be transformed into mechanical energy and extracted during the expansion process. A new type of isothermal steam expander for an industrial steam supplying system will be presented in the paper. The isothermal steam expander will improve the energy efficiency of a traditional steam expander by replacing the isentropic process with an isothermal expansion process. With this, steam condensation will decrease, energy will increase, and steam quality will be improved. Moreover, the mathematical model of the isothermal steam expander will be established by using the Schmidt theory, the same principle used to analyze Stirling engines. Consequently, by verifying the correctness of the theoretical model for the isothermal steam expander using experimental data, a prototype of 100 c.c. isothermal steam expander is constructed.

  19. Effect of annealing temperature on the microstructure and tensile properties of a bimodal nano/micro grained 1020 carbon steel prepared by aluminothermic reaction casting

    Science.gov (United States)

    La, Peiqing; Guo, Xin; Wang, Hongding; Shi, Ting; Zhen, Xiaojuan; Wei, Fuan; Lu, Xuefeng

    2016-03-01

    Bulk 1020 carbon steel was prepared by aluminothermic reaction casting. After casting, isothermal aging treatments at different temperatures are performed for different periods up to 8 h. Microstructure characterization was performed using many methods, including optical microscopy, X-ray diffraction, scanning electron microscopy and transmission electron microscopy. It was found that the steel consisted of a nanocrystalline- ferrite matrix and a microcrystalline pearlite phase with a laminar structure. The average grain sizes of the ferrite were 23, 24, 28, and 37 nm for the cast steel and for samples annealed at 600, 800, and 1000 °C, respectively. As the annealing temperature increased, the volume fraction of the pearlite initially increased and then decreased, while the laminar spacing of pearlite increased from 240 to 900 nm. When annealed at 1000 °C, a spherical black micron pearlite particle was formed. The tensile and yield strength dramatically decreased, and the elongation varied slightly with the annealing temperature. A ductile phase was achieved by extending the holding time.

  20. Effect of isochronal annealing on phase transformation studies of ...

    Indian Academy of Sciences (India)

    Abstract. The effect of isochronal annealing on the phase transformation in iron oxide nanoparticles is reported in this work. Iron oxide ... The phase transformation is complete at annealing temperature of 442◦C as confirmed by differential ..... Han S, Yu T, Park J, Koo B, Joo J, Hyeon T, Hong S and Im J. 2004 J. Phys. Chem.

  1. Electrical annealing of severely deformed copper: microstructure and hardness

    Science.gov (United States)

    Nobakht, Saeed; Kazeminezhad, Mohsen

    2017-10-01

    Commercial pure copper sheets were severely deformed after primary annealing to a strain magnitude of 2.32 through constrained groove pressing. After induction of an electrical current, the sheets were heated for 0.5, 1, 2, or 3 s up to maximum temperatures of 150, 200, 250, or 300°C. To compare the annealing process in the current-carrying system with that in the current-free system, four other samples were heated to 300°C at holding times of 60, 90, 120, or 150 s in a salt bath. The microstructural evolution and hardness values of the samples were then investigated. The results generally indicated that induction of an electrical current could accelerate the recrystallization process by decreasing the thermodynamic barriers for nucleation. In other words, the current effect, in addition to the thermal effect, enhanced the diffusion rate and dislocation climb velocity. During the primary stages of recrystallization, the grown nuclei of electrically annealed samples showed greater numbers and a more homogeneous distribution than those of the samples annealed in the salt bath. In the fully recrystallized condition, the grain size of electrically annealed samples was smaller than that of conventionally annealed samples. The hardness values and metallographic images obtained indicate that, unlike the conventional annealing process, which promotes restoration phenomena with increasing heating time, the electrical annealing process does not necessarily promote these phenomena. This difference is hypothesized to stem from conflicts between thermal and athermal effects during recrystallization.

  2. Effect of isochronal annealing on phase transformation studies of ...

    Indian Academy of Sciences (India)

    The effect of isochronal annealing on the phase transformation in iron oxide nanoparticles is reported in this work. Iron oxide nanoparticles were successfully synthesized using an ash supported technique followed by annealing for 2 h at various temperatures between 300 and 700° C. It was observed using X-ray diffraction ...

  3. Influence of degree of deformation in rolling on anneal hardening ...

    Indian Academy of Sciences (India)

    Unknown

    increase in the electrical conductivity. The amount of strengthening increases with increasing degree of prior cold work. The X-ray analysis shows a change in the lattice parameter during annealing when anneal hardening effect was observed. ... The strength properties of cold-worked substitutional solid solutions increased ...

  4. Effect of heat moisture treatment and annealing on physicochemical ...

    African Journals Online (AJOL)

    Red sorghum starch was physically modified by annealing and heat moisture treatment. The swelling power and solubility increased with increasing temperature range (60-90°), while annealing and heatmoisture treatment decreased swelling power and solubility of starch. Solubility and swelling were pH dependent with ...

  5. Angular filter refractometry analysis using simulated annealing.

    Science.gov (United States)

    Angland, P; Haberberger, D; Ivancic, S T; Froula, D H

    2017-10-01

    Angular filter refractometry (AFR) is a novel technique used to characterize the density profiles of laser-produced, long-scale-length plasmas [Haberberger et al., Phys. Plasmas 21, 056304 (2014)]. A new method of analysis for AFR images was developed using an annealing algorithm to iteratively converge upon a solution. A synthetic AFR image is constructed by a user-defined density profile described by eight parameters, and the algorithm systematically alters the parameters until the comparison is optimized. The optimization and statistical uncertainty calculation is based on the minimization of the χ(2) test statistic. The algorithm was successfully applied to experimental data of plasma expanding from a flat, laser-irradiated target, resulting in an average uncertainty in the density profile of 5%-20% in the region of interest.

  6. Annealing a magnetic cactus into phyllotaxis

    Science.gov (United States)

    Nisoli, Cristiano; Gabor, Nathaniel M.; Lammert, Paul E.; Maynard, J. D.; Crespi, Vincent H.

    2010-04-01

    The appearance of mathematical regularities in the disposition of leaves on a stem, scales on a pine-cone, and spines on a cactus has puzzled scholars for millennia; similar so-called phyllotactic patterns are seen in self-organized growth, polypeptides, convection, magnetic flux lattices and ion beams. Levitov showed that a cylindrical lattice of repulsive particles can reproduce phyllotaxis under the (unproved) assumption that minimum of energy would be achieved by two-dimensional Bravais lattices. Here we provide experimental and numerical evidence that the Phyllotactic lattice is actually a ground state. When mechanically annealed, our experimental “magnetic cactus” precisely reproduces botanical phyllotaxis, along with domain boundaries (called transitions in Botany) between different phyllotactic patterns. We employ a structural genetic algorithm to explore the more general axially unconstrained case, which reveals multijugate (multiple spirals) as well as monojugate (single-spiral) phyllotaxis.

  7. Entanglement in a Quantum Annealing Processor

    Science.gov (United States)

    Lanting, T.; Przybysz, A. J.; Smirnov, A. Yu.; Spedalieri, F. M.; Amin, M. H.; Berkley, A. J.; Harris, R.; Altomare, F.; Boixo, S.; Bunyk, P.; Dickson, N.; Enderud, C.; Hilton, J. P.; Hoskinson, E.; Johnson, M. W.; Ladizinsky, E.; Ladizinsky, N.; Neufeld, R.; Oh, T.; Perminov, I.; Rich, C.; Thom, M. C.; Tolkacheva, E.; Uchaikin, S.; Wilson, A. B.; Rose, G.

    2014-04-01

    Entanglement lies at the core of quantum algorithms designed to solve problems that are intractable by classical approaches. One such algorithm, quantum annealing (QA), provides a promising path to a practical quantum processor. We have built a series of architecturally scalable QA processors consisting of networks of manufactured interacting spins (qubits). Here, we use qubit tunneling spectroscopy to measure the energy eigenspectrum of two- and eight-qubit systems within one such processor, demonstrating quantum coherence in these systems. We present experimental evidence that, during a critical portion of QA, the qubits become entangled and entanglement persists even as these systems reach equilibrium with a thermal environment. Our results provide an encouraging sign that QA is a viable technology for large-scale quantum computing.

  8. Angular filter refractometry analysis using simulated annealing

    Science.gov (United States)

    Angland, P.; Haberberger, D.; Ivancic, S. T.; Froula, D. H.

    2017-10-01

    Angular filter refractometry (AFR) is a novel technique used to characterize the density profiles of laser-produced, long-scale-length plasmas [Haberberger et al., Phys. Plasmas 21, 056304 (2014)]. A new method of analysis for AFR images was developed using an annealing algorithm to iteratively converge upon a solution. A synthetic AFR image is constructed by a user-defined density profile described by eight parameters, and the algorithm systematically alters the parameters until the comparison is optimized. The optimization and statistical uncertainty calculation is based on the minimization of the χ2 test statistic. The algorithm was successfully applied to experimental data of plasma expanding from a flat, laser-irradiated target, resulting in an average uncertainty in the density profile of 5%-20% in the region of interest.

  9. Infrared study on annealing effect on conformation of zinc stearate.

    Science.gov (United States)

    Ishioka, Tsutomu; Kiritani, Atsushi; Kojima, Takuya

    2007-04-01

    The molecular conformation and thermal transition behavior of two zinc stearate specimens, unannealed one and annealed one, were compared. The unannealed specimen has one thermal transition at 134 degrees C. Annealing was made by increasing temperature to 150 degrees C and cooling to room temperature slowly. This annealed specimen has an exothermic peak at 103 degrees C, and endothermic shoulders and a peak at 118, 124 and 131 degrees C, respectively. The observed frequencies of all bands of the unannealed specimen at room temperature are assigned to the all-trans conformation. We found new bands at 858, 823, 793, 766, 688, and 604 cm-1 for the annealed specimen. Based on the normal mode analyses, these bands are assigned to the TGT conformation at the COO end, where T means trans and G means gauche. The annealed specimen consists of almost all-trans molecule but partial molecules have the TGT conformation.

  10. Stored energy and annealing behavior of heavily deformed aluminium

    DEFF Research Database (Denmark)

    Kamikawa, Naoya; Huang, Xiaoxu; Kondo, Yuka

    2012-01-01

    are quantified such as boundary spacing, misorientation angle and dislocation density for 99.99% aluminium deformed by accumulative roll-bonding to a strain of 4.8. Two different annealing processes have been applied; (i) one-step annealing for 0.5 h at 100-400°C and (ii) two-step annealing for 6 h at 175°C...... followed by 0.5 h annealing at 200-600°C, where the former treatment leads to discontinuous recrystallization and the latter to uniform structural coarsening. This behavior has been analyzed in terms of the relative change during annealing of energy stored as elastic energy in the dislocation structure...

  11. A study on moisture isotherms of formulations: the Use of polynomial equations to predict the moisture isotherms of tablet products

    OpenAIRE

    Li, Yanxia; Sanzgiri, Yeshwant D.; Chen, Yisheng

    2003-01-01

    The objectives of this study were to investigate the effects of manufacturing parameters on the moisture sorption isotherms of some tablet formulations and to predict the moisture isotherms of the final formulations using polynomial equations. Three tablet formulations including a placebo and 2 drug products were prepared through wet granulation, drying, compression, and coating processes. Equilibrium moisture content of excipients and granules at 25°C with different relative humidities were ...

  12. Production of valuable pyrolytic oils from mixed Municipal Solid Waste (MSW in Indonesia using non-isothermal and isothermal experimental

    Directory of Open Access Journals (Sweden)

    Indra Mamad Gandidi

    2017-09-01

    Full Text Available Municipal solid waste (MSW, disposed of at open dumping sites, poses health risks, contaminates surface water, and releases greenhouse gasses such as methane. However, pyrolysis offers the opportunity to convert MSW into Bio-Oil (BO for clean energy resource. In this paper, an MSW sample consisting of plastic, paper and cardboard, rubber and textiles, and vegetable waste is pyrolysed on a laboratory scale in a fixed-bed vacuum reactor. In the non-isothermal process, the sample was fed into the reactor and then heated. In the isothermal process, the reactor is first heated and then the sample is added. The non-isothermal process created greater BO in both quality and quantity. The BO had a larger amount of gasoline species than diesel-48 fuel, with at 33.44%the BO produced by isothermal pyrolysis and 36.42% in non-isothermal pyrolysis. However the product of isothermal pyrolysis had a higher acid content that reduced its heating value.

  13. Isothermal and non-isothermal infiltration and deuterium transport: a case study on undisturbed soil column from headwater catchment

    Science.gov (United States)

    Sobotkova, Martina; Snehota, Michal; Tesar, Miroslav

    2017-04-01

    Isothermal and non-isothermal infiltration experiments with tracer breakthrough were carried out in the laboratory on intact column of sandy loam soil taken from Roklan site (Sumava Mountains, Czech Republic). In the case of isothermal experiment, the temperature of infiltrating water was almost equal to the initial temperature of the sample. For the non-isothermal case the infiltration was performed using water approximately 10 °C colder than was the initial temperature of soil sample. The experiments were otherwise conducted under the same initial and boundary conditions. Pressure heads and temperatures in two depths (8.8 and 15.3 cm) inside the soil were monitored as well as the temperature of water entering and leaving the sample. Water drained freely through the perforated plate at the bottom of the sample by gravity and outflow was measured using tipping bucket flowmeter. Permeability of the sample calculated for steady state stages of the experiment showed that significant difference between water flow rates recorded during two experiment could not be justified only by temperature induced changes of water viscosity and density. Results of deuterium breakthrough were nearly identical for isothermal and non-isothermal conditions.

  14. Non-isothermal crystallization kinetics of As{sub 30}Te{sub 60}Ga{sub 10} glass

    Energy Technology Data Exchange (ETDEWEB)

    Mohamed, Mansour; Abd-Elnaiem, Alaa M.; Abdel-Rahim, M.A.; Hafiz, M.M. [Assiut University, Physics Department, Faculty of Science, Assiut (Egypt); Hassan, R.M. [Assiut University, Physics Department, Faculty of Science, Assiut (Egypt); Aden University, Physics Department, Faculty of Education-Zingiber, Aden (Yemen)

    2017-08-15

    The crystallization study under non-isothermal conditions of As{sub 30}Te{sub 60}Ga{sub 10} glass was investigated. The studied composition was synthesized by melt-quenching technique and characterized by different techniques such as X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and differential scanning calorimetry (DSC). The XRD analysis revealed that the as-prepared and annealed bulk glass of As{sub 30}Te{sub 60}Ga{sub 10} exhibit the amorphous, and polycrystalline nature, respectively. The DSC results showed that the heating rate affects the characteristic temperatures, for instance, the glass transition, onset, and peak crystallization temperatures. Furthermore, some thermal analysis methods such as the Kissinger and Matusita et al., approximations were employed to determine the crystallization parameters: for example Avrami exponent and the activation energies for glass transition and crystallization process. In addition, we have compared the experimental DSC data with the calculated ones based on the Johnson-Mehl-Avrami (JMA) and Sestak-Berggren SB(M,N) models. The results indicated that the SB(M,N) model is more suitable for describing the non-isothermal crystallization kinetics of the investigated composition. (orig.)

  15. Differential binding models for isothermal titration calorimetry: moving beyond the Wiseman isotherm.

    Science.gov (United States)

    Herrera, Isaac; Winnik, Mitchell A

    2013-07-25

    We present a set of model-independent differential equations to analyze isothermal titration calorimetry (ITC) experiments. In contrast with previous approaches that begin with specific assumptions about the number of binding sites and the interactions among them (e.g., sequential, independent, cooperative), our derivation makes more general assumptions, such that a receptor with multiple sites for one type of ligand species (homotropic binding) can be studied with the same analytical expression. Our approach is based on the binding polynomial formalism, and the resulting analytical expressions can be extended to account for any number of binding sites and any type of binding interaction among them. We refer to the set of model-independent differential equations to study ITC experiments as a differential binding model (DBM). To demonstrate the flexibility of our DBM, we present the analytical expressions to study receptors with one or two binding sites. The DBM for a receptor with one site is equivalent to the Wiseman isotherm but with a more intuitive representation that depends on the binding polynomial and the dimensionless parameter c = K·MT, where K is the binding constant and MT the total receptor concentration. In addition, we show how to constrain the general DBM for a receptor with two sites to represent sequential, independent, or cooperative binding interactions between the sites. We use the sequential binding model to study the binding interaction between Gd(III) and citrate anions. In addition, we simulate calorimetry titrations of receptors with positive, negative, and noncooperative interactions between the two binding sites. Finally, we derive a DBM for titrations of receptors with n-independent binding sites.

  16. Advanced phase change composite by thermally annealed defect-free graphene for thermal energy storage.

    Science.gov (United States)

    Xin, Guoqing; Sun, Hongtao; Scott, Spencer Michael; Yao, Tiankai; Lu, Fengyuan; Shao, Dali; Hu, Tao; Wang, Gongkai; Ran, Guang; Lian, Jie

    2014-09-10

    Organic phase change materials (PCMs) have been utilized as latent heat energy storage and release media for effective thermal management. A major challenge exists for organic PCMs in which their low thermal conductivity leads to a slow transient temperature response and reduced heat transfer efficiency. In this work, 2D thermally annealed defect-free graphene sheets (GSs) can be obtained upon high temperature annealing in removing defects and oxygen functional groups. As a result of greatly reduced phonon scattering centers for thermal transport, the incorporation of ultralight weight and defect free graphene applied as nanoscale additives into a phase change composite (PCC) drastically improve thermal conductivity and meanwhile minimize the reduction of heat of fusion. A high thermal conductivity of the defect-free graphene-PCC can be achieved up to 3.55 W/(m K) at a 10 wt % graphene loading. This represents an enhancement of over 600% as compared to pristine graphene-PCC without annealing at a comparable loading, and a 16-fold enhancement than the pure PCM (1-octadecanol). The defect-free graphene-PCC displays rapid temperature response and superior heat transfer capability as compared to the pristine graphene-PCC or pure PCM, enabling transformational thermal energy storage and management.

  17. The Effect of Solution Annealing on the Microstructural Behavior of Alloy 22 Welds

    Energy Technology Data Exchange (ETDEWEB)

    El-Dasher, B S; Edgecumbe, T S; Torres, S G

    2005-05-06

    Multi-pass gas tungsten arc welds of Alloy 22 were subjected to solution annealing durations of 20 minutes, 24 hours, 72 hours and 1 week at temperatures of 1075, 1121, 1200, and 1300 C. The specimens were studied in cross section by secondary electron microscopy to determine the effect of solution annealing on tetrahedrally close packed (TCP) precipitate stability. Electron backscatter diffraction mapping was also performed on all of the specimens to determine the recrystallization behavior of the welds. It was found that complete TCP precipitate dissolution occurs after solution annealing at 1075 C and 1121 C for 24 hours, and at 1200 C and 1300 C for durations of 20 minutes. Regions of most rapid recrystallization were correlated to the regions of lowest solute content and highest residual tensile stresses. Texture analysis indicated that while the columnar dendrites originally present in the weld grew with a <001> orientation in the transverse direction (opposite the heat flow direction), the recrystallized grains adopt a <101> orientation in the transverse direction when recrystallization and TCP phase dissolution occur simultaneously.

  18. Fission-track annealing characteristics of meteoritic phosphates

    Energy Technology Data Exchange (ETDEWEB)

    Mold, P.; Bull, R.K.; Durrani, S.A. (Birmingham Univ. (UK). Dept. of Physics)

    1984-01-01

    Laboratory annealing experiments have been conducted on merrillite and chlorapatite crystals from the Estacado (H6) chondrite, and on merrillite from the Bondoc mesosiderite. The annealing behaviour of the two phosphate minerals in Estacado was found to differ in that the annealing curves obtained were distinct for each mineral and temperatures required for total annealing of fossil tracks were significantly higher for merrillite than for apatite. Nevertheless, estimates of effective closing temperatures for these minerals, on the basis of experimental results obtained to date, do not indicate a significant difference between the two (84 +- 10 deg C for Estacado merrillite; 66 +- 10 deg C for Estacado apatite); both estimates being based on the annealing of fossil tracks and assuming a cooling-rate of approx. 1 deg C/Myr. Annealing expriments were also conducted with merrillite from the Bondoc mesosiderite, and both fossil and freshly-induced tracks were found to be less easily annealed than in the case of Estacado merrillite. An estimated closing temperature of 134 +- 15 deg C was deduced from the results so far obtained, using freshly-induced tracks and assuming a cooling-rate of 0.2 deg C/Myr.

  19. Effects on external quantum efficiency of electrochemically constructed n-ZnO/p-Cu2O photovoltaic device by annealing

    Science.gov (United States)

    Khoo, Pei Loon; Kikkawa, Yuuki; Shinagawa, Tsutomu; Izaki, Masanobu

    2017-07-01

    Cuprous oxide (Cu2O), a terrestrial abundant, low cost, nontoxic, intrinsically p-type oxide semiconductor with bandgap energy of about 2eV, has recently received increasing attention as a light absorbing layer in solar cells. However, the performances of electrochemically constructed Cu2O solar devices are poor compared to the theoretical power conversion efficiency. This research was conducted focusing on the EQE performance, which is closely related to the short circuit current of a solar device. ZnO/Cu2O-PV-devices were constructed electrochemically with 3-electrode cell on Ga:ZnO/SLG substrates; ZnO layers were deposited from an aqueous solution of 8 mmolL-1 zinc nitrate hexahydrate at 63°C, 0.01 Coulomb cm-2, and -0.8V, while Cu2O layers were deposited from aqueous solution containing 0.4 molL-1 copper (II) acetate monohydrate (pH12.5), at 40°C, 1.5 Coulomb cm-2, and -0.4V. Devices were then annealed under different temperatures of 150°C, 200°C, 250°C, and 300°C for 60 minutes with a Rapid Thermal Anneal furnace (RTA). The EQE of the devices were measured with a spectral sensitivity device and compared to the non-annealed device. Further studies were made such as morphology observation of the films by FE-SEM and measurements of X-ray diffraction patterns. Annealed samples showed improved maximum EQE at 150-200°C of annealing, indicating that EQE above 90% can be achieved, proving the validity of EQE improvement via low temperature annealing method for thin film Cu2O photovoltaic devices.

  20. Annealed Scaling for a Charged Polymer

    Energy Technology Data Exchange (ETDEWEB)

    Caravenna, F., E-mail: francesco.caravenna@unimib.it [Università degli Studi di Milano-Bicocca, Dipartimento di Matematica e Applicazioni (Italy); Hollander, F. den, E-mail: denholla@math.leidenuniv.nl [Leiden University, Mathematical Institute (Netherlands); Pétrélis, N., E-mail: nicolas.petrelis@univ-nantes.fr [Université de Nantes, Laboratoire de Mathématiques Jean Leray UMR 6629 (France); Poisat, J., E-mail: poisat@ceremade.dauphine.fr [Université Paris-Dauphine, PSL Research University, CEREMADE, UMR 7534 (France)

    2016-03-15

    This paper studies an undirected polymer chain living on the one-dimensional integer lattice and carrying i.i.d. random charges. Each self-intersection of the polymer chain contributes to the interaction Hamiltonian an energy that is equal to the product of the charges of the two monomers that meet. The joint probability distribution for the polymer chain and the charges is given by the Gibbs distribution associated with the interaction Hamiltonian. The focus is on the annealed free energy per monomer in the limit as the length of the polymer chain tends to infinity. We derive a spectral representation for the free energy and use this to prove that there is a critical curve in the parameter plane of charge bias versus inverse temperature separating a ballistic phase from a subballistic phase. We show that the phase transition is first order. We prove large deviation principles for the laws of the empirical speed and the empirical charge, and derive a spectral representation for the associated rate functions. Interestingly, in both phases both rate functions exhibit flat pieces, which correspond to an inhomogeneous strategy for the polymer to realise a large deviation. The large deviation principles in turn lead to laws of large numbers and central limit theorems. We identify the scaling behaviour of the critical curve for small and for large charge bias. In addition, we identify the scaling behaviour of the free energy for small charge bias and small inverse temperature. Both are linked to an associated Sturm-Liouville eigenvalue problem. A key tool in our analysis is the Ray-Knight formula for the local times of the one-dimensional simple random walk. This formula is exploited to derive a closed form expression for the generating function of the annealed partition function, and for several related quantities. This expression in turn serves as the starting point for the derivation of the spectral representation for the free energy, and for the scaling theorems

  1. Embrittlement recovery due to annealing of reactor pressure vessel steels

    Energy Technology Data Exchange (ETDEWEB)

    Eason, E.D.; Wright, J.E.; Nelson, E.E. [Modeling and Computing Services, Boulder, CO (United States); Odette, G.R.; Mader, E.V. [Univ. of California, Santa Barbara, CA (United States)

    1996-03-01

    Embrittlement of reactor pressure vessels (RPVs) can be reduced by thermal annealing at temperatures higher than the normal operating conditions. Although such an annealing process has not been applied to any commercial plants in the United States, one US Army reactor, the BR3 plant in Belgium, and several plants in eastern Europe have been successfully annealed. All available Charpy annealing data were collected and analyzed in this project to develop quantitative models for estimating the recovery in 30 ft-lb (41 J) Charpy transition temperature and Charpy upper shelf energy over a range of potential annealing conditions. Pattern recognition, transformation analysis, residual studies, and the current understanding of the mechanisms involved in the annealing process were used to guide the selection of the most sensitive variables and correlating parameters and to determine the optimal functional forms for fitting the data. The resulting models were fitted by nonlinear least squares. The use of advanced tools, the larger data base now available, and insight from surrogate hardness data produced improved models for quantitative evaluation of the effects of annealing. The quality of models fitted in this project was evaluated by considering both the Charpy annealing data used for fitting and the surrogate hardness data base. The standard errors of the resulting recovery models relative to calibration data are comparable to the uncertainty in unirradiated Charpy data. This work also demonstrates that microhardness recovery is a good surrogate for transition temperature shift recovery and that there is a high level of consistency between the observed annealing trends and fundamental models of embrittlement and recovery processes.

  2. Anisotropic annealing of fission fragments in synthetic quartz

    CERN Document Server

    Sawamura, T; Narita, M

    1999-01-01

    A study on the thermal annealing behavior of fission fragments in synthetic quartz crystals was performed for application of synthetic quartz to track detectors under high temperature circumstances: x-, y-, and z-cut quartz plates were exposed to fission fragments from sup 2 sup 5 sup 2 Cf and were annealed up to 750 deg. C. It was found that track retention depended on the crystallographic structure: the annealing temperature, where the number of etched tracks was sharply reduced, was 550 deg. C for the x- and y-cut plates and 750 deg. C for z-cut plates. Track sizes decrease and disperse with reductions in the track retention.

  3. Quantum annealing of the traveling-salesman problem.

    Science.gov (United States)

    Martonák, Roman; Santoro, Giuseppe E; Tosatti, Erio

    2004-11-01

    We propose a path-integral Monte Carlo quantum annealing scheme for the symmetric traveling-salesman problem, based on a highly constrained Ising-like representation, and we compare its performance against standard thermal simulated annealing. The Monte Carlo moves implemented are standard, and consist in restructuring a tour by exchanging two links (two-opt moves). The quantum annealing scheme, even with a drastically simple form of kinetic energy, appears definitely superior to the classical one, when tested on a 1002-city instance of the standard TSPLIB.

  4. Annealing properties of potato starches with different degrees of phosphorylation

    DEFF Research Database (Denmark)

    Muhrbeck, Per; Svensson, E

    1996-01-01

    Changes in the gelatinization temperature interval and gelatinization enthalpy with annealing time at 50 degrees C were followed for a number of potato starch samples, with different degrees of phosphorylation, using differential scanning calorimetry. The gelatinization temperature increased...... with the length of the annealing time up to the maximum time of 1280 min and a clear relation to the degree of phosphorylation was observed. The gelatinization enthalpy changed very slowly during the initial period of annealing, but faster in the later stages of the process. The increase in enthalpy was largest...

  5. Synthesis-dependent strand annealing in meiosis.

    Directory of Open Access Journals (Sweden)

    Melissa S McMahill

    2007-11-01

    Full Text Available Recent studies led to the proposal that meiotic gene conversion can result after transient engagement of the donor chromatid and subsequent DNA synthesis-dependent strand annealing (SDSA. Double Holliday junction (dHJ intermediates were previously proposed to form both reciprocal crossover recombinants (COs and noncrossover recombinants (NCOs; however, dHJs are now thought to give rise mainly to COs, with SDSA forming most or all NCOs. To test this model in Saccharomyces cerevisiae, we constructed a random spore system in which it is possible to identify a subset of NCO recombinants that can readily be accounted for by SDSA, but not by dHJ-mediated recombination. The diagnostic class of recombinants is one in which two markers on opposite sides of a double-strand break site are converted, without conversion of an intervening heterologous insertion located on the donor chromatid. This diagnostic class represents 26% of selected NCO recombinants. Tetrad analysis using the same markers provided additional evidence that SDSA is a major pathway for NCO gene conversion in meiosis.

  6. Synthesis-dependent strand annealing in meiosis.

    Science.gov (United States)

    McMahill, Melissa S; Sham, Caroline W; Bishop, Douglas K

    2007-11-06

    Recent studies led to the proposal that meiotic gene conversion can result after transient engagement of the donor chromatid and subsequent DNA synthesis-dependent strand annealing (SDSA). Double Holliday junction (dHJ) intermediates were previously proposed to form both reciprocal crossover recombinants (COs) and noncrossover recombinants (NCOs); however, dHJs are now thought to give rise mainly to COs, with SDSA forming most or all NCOs. To test this model in Saccharomyces cerevisiae, we constructed a random spore system in which it is possible to identify a subset of NCO recombinants that can readily be accounted for by SDSA, but not by dHJ-mediated recombination. The diagnostic class of recombinants is one in which two markers on opposite sides of a double-strand break site are converted, without conversion of an intervening heterologous insertion located on the donor chromatid. This diagnostic class represents 26% of selected NCO recombinants. Tetrad analysis using the same markers provided additional evidence that SDSA is a major pathway for NCO gene conversion in meiosis.

  7. The RNA annealing mechanism of the HIV-1 Tat peptide: conversion of the RNA into an annealing-competent conformation.

    Science.gov (United States)

    Doetsch, Martina; Fürtig, Boris; Gstrein, Thomas; Stampfl, Sabine; Schroeder, Renée

    2011-05-01

    The annealing of nucleic acids to (partly) complementary RNA or DNA strands is involved in important cellular processes. A variety of proteins have been shown to accelerate RNA/RNA annealing but their mode of action is still mainly uncertain. In order to study the mechanism of protein-facilitated acceleration of annealing we selected a short peptide, HIV-1 Tat(44-61), which accelerates the reaction efficiently. The activity of the peptide is strongly regulated by mono- and divalent cations which hints at the importance of electrostatic interactions between RNA and peptide. Mutagenesis of the peptide illustrated the dominant role of positively charged amino acids in RNA annealing--both the overall charge of the molecule and a precise distribution of basic amino acids within the peptide are important. Additionally, we found that Tat(44-61) drives the RNA annealing reaction via entropic rather than enthalpic terms. One-dimensional-NMR data suggest that the peptide changes the population distribution of possible RNA structures to favor an annealing-prone RNA conformation, thereby increasing the fraction of colliding RNA molecules that successfully anneal.

  8. Determination of Differential Enthalpy and Isotherm by Adsorption Calorimetry

    Directory of Open Access Journals (Sweden)

    V. Garcia-Cuello

    2008-01-01

    Full Text Available An adsorption microcalorimeter for the simultaneous determination of the differential heat of adsorption and the adsorption isotherm for gas-solid systems are designed, built, and tested. For this purpose, a Calvet heat-conducting microcalorimeter is developed and is connected to a gas volumetric unit built in stainless steel to record adsorption isotherms. The microcalorimeter is electrically calibrated to establish its sensitivity and reproducibility, obtaining K=154.34±0.23 WV−1. The adsorption microcalorimeter is used to obtain adsorption isotherms and the corresponding differential heats for the adsorption of CO2 on a reference solid, such as a NaZSM-5 type zeolite. Results for the behavior of this system are compared with those obtained with commercial equipment and with other studies in the literature.

  9. Sorption isotherms: A review on physical bases, modeling and measurement

    Energy Technology Data Exchange (ETDEWEB)

    Limousin, G. [Atomic Energy Commission, Tracers Technology Laboratory, 38054 Grenoble Cedex (France) and Laboratoire d' etude des Transferts en Hydrologie et Environnement (CNRS-INPG-IRD-UJF), BP 53, 38041 Grenoble Cedex (France)]. E-mail: guillaumelimousin@yahoo.fr; Gaudet, J.-P. [Laboratoire d' etude des Transferts en Hydrologie et Environnement (CNRS-INPG-IRD-UJF), BP 53, 38041 Grenoble Cedex (France); Charlet, L. [Laboratoire de Geophysique Interne et Techtonophysique - CNRS-IRD-LCPC-UJF-Universite de Savoie, BP 53, 38041 Grenoble Cedex (France); Szenknect, S. [Atomic Energy Commission, Tracers Technology Laboratory, 38054 Grenoble Cedex (France); Barthes, V. [Atomic Energy Commission, Tracers Technology Laboratory, 38054 Grenoble Cedex (France); Krimissa, M. [Electricite de France, Division Recherche et Developpement, Laboratoire National d' Hydraulique et d' Environnement - P78, 6 quai Watier, 78401 Chatou (France)

    2007-02-15

    The retention (or release) of a liquid compound on a solid controls the mobility of many substances in the environment and has been quantified in terms of the 'sorption isotherm'. This paper does not review the different sorption mechanisms. It presents the physical bases underlying the definition of a sorption isotherm, different empirical or mechanistic models, and details several experimental methods to acquire a sorption isotherm. For appropriate measurements and interpretations of isotherm data, this review emphasizes 4 main points: (i) the adsorption (or desorption) isotherm does not provide automatically any information about the reactions involved in the sorption phenomenon. So, mechanistic interpretations must be carefully verified. (ii) Among studies, the range of reaction times is extremely wide and this can lead to misinterpretations regarding the irreversibility of the reaction: a pseudo-hysteresis of the release compared with the retention is often observed. The comparison between the mean characteristic time of the reaction and the mean residence time of the mobile phase in the natural system allows knowing if the studied retention/release phenomenon should be considered as an instantaneous reversible, almost irreversible phenomenon, or if reaction kinetics must be taken into account. (iii) When the concentration of the retained substance is low enough, the composition of the bulk solution remains constant and a single-species isotherm is often sufficient, although it remains strongly dependent on the background medium. At higher concentrations, sorption may be driven by the competition between several species that affect the composition of the bulk solution. (iv) The measurement method has a great influence. Particularly, the background ionic medium, the solid/solution ratio and the use of flow-through or closed reactor are of major importance. The chosen method should balance easy-to-use features and representativity of the studied

  10. A discrete version of the Darboux transform for isothermic surfaces

    CERN Document Server

    Hertrich-Jeromin, U J; Pinkall, U; Hertrich-Jeromin, Udo; Hoffmann, Tim; Pinkall, Ulrich

    1996-01-01

    We study Christoffel and Darboux transforms of discrete isothermic nets in 4-dimensional Euclidean space: definitions and basic properties are derived. Analogies with the smooth case are discussed and a definition for discrete Ribaucour congruences is given. Surfaces of constant mean curvature are special among all isothermic surfaces: they can be characterized by the fact that their parallel constant mean curvature surfaces are Christoffel and Darboux transforms at the same time. This characterization is used to define discrete nets of constant mean curvature. Basic properties of discrete nets of constant mean curvature are derived.

  11. Isothermal Gas assisted displacement of a polystyrene melt

    DEFF Research Database (Denmark)

    Eriksson, Torbjörn Gerhard; Rasmussen, Henrik K.

    2007-01-01

    Isothermal gas displacements of a polystyrene melt (shaped as circular cylinder with a radius of 2.5mm) placed inside a circular steel annulus were performed. A flow valve ensures a constant flow rate and rotational symmetric flow during the displacement. The experiments show an increase in the s......Isothermal gas displacements of a polystyrene melt (shaped as circular cylinder with a radius of 2.5mm) placed inside a circular steel annulus were performed. A flow valve ensures a constant flow rate and rotational symmetric flow during the displacement. The experiments show an increase...

  12. Interpretation of Quasi-Isothermal Thermogravimetric Weight Curves

    DEFF Research Database (Denmark)

    Sørensen, Ole Toft

    1979-01-01

    Quasi-isothermal analysis (QIA) is a very useful technique. Compared to conventional non-isothermal thermogravimetry, close-lying reactions can easily be separated by use of this method and kinetic data can be obtained for each intermediate reaction in a single run. This paper discusses the shape...... of the weight and temperature curves expected in QIA for different controlling mechanisms, and a method is given for calculating the activation energies from these curves. As an example, the QIA curves obtained in thermal decomposition of ammonium-uranyl carbonate (AUC) are analysed and the kinetics of some...... of the intermediate reactions are determined....

  13. Non-stoquastic Hamiltonians in quantum annealing via geometric phases

    National Research Council Canada - National Science Library

    Walter Vinci; Daniel A Lidar

    2017-01-01

    We argue that a complete description of quantum annealing implemented with continuous variables must take into account the non-adiabatic Aharonov-Anandan geometric phase that arises when the system...

  14. Homogenization of CZ Si wafers by Tabula Rasa annealing

    Energy Technology Data Exchange (ETDEWEB)

    Meduna, M., E-mail: mjme@physics.muni.c [Department of Condensed Matter Physics, Masaryk University, Kotlarska 2, CZ-61137 Brno (Czech Republic); Caha, O.; Kubena, J.; Kubena, A. [Department of Condensed Matter Physics, Masaryk University, Kotlarska 2, CZ-61137 Brno (Czech Republic); Bursik, J. [Institute of Physics of Materials, Academy of Sciences of the Czech Republic, Zizkova 22, CZ-61662 Brno (Czech Republic)

    2009-12-15

    The precipitation of interstitial oxygen in Czochralski grown silicon has been investigated by infrared absorption spectroscopy, chemical etching, transmission electron microscopy and X-ray diffraction after application of homogenization annealing process called Tabula Rasa. The influence of this homogenization step consisting in short time annealing at high temperature has been observed for various temperatures and times. The experimental results involving the interstitial oxygen decay in Si wafers and absorption spectra of SiO{sub x} precipitates during precipitation annealing at 1000 deg. C were compared with other techniques for various Tabula Rasa temperatures. The differences in oxygen precipitation, precipitate morphology and evolution of point defects in samples with and without Tabula Rasa applied is evident from all used experimental techniques. The results qualitatively correlate with prediction of homogenization annealing process based on classical nucleation theory.

  15. Tunable cobalt nanoparticle synthesis by intense pulse flash annealing

    National Research Council Canada - National Science Library

    Mosey, Aaron; Gaire, Babu; Kim, Jeongwhan; Ryu, Jong Eun; Cheng, Ruihua

    2017-01-01

    .... Here we report a cost-effective method to synthesize magnetic nanoparticles. Samples were fabricated by sputtering magnetic thin films on carbon nanotube substrates followed by xenon intense pulsed light flash annealing...

  16. Solvent vapor annealing of an insoluble molecular semiconductor

    KAUST Repository

    Amassian, Aram

    2010-01-01

    Solvent vapor annealing has been proposed as a low-cost, highly versatile, and room-temperature alternative to thermal annealing of organic semiconductors and devices. In this article, we investigate the solvent vapor annealing process of a model insoluble molecular semiconductor thin film - pentacene on SiO 2 exposed to acetone vapor - using a combination of optical reflectance and two-dimensional grazing incidence X-ray diffraction measurements performed in situ, during processing. These measurements provide valuable and new insight into the solvent vapor annealing process; they demonstrate that solvent molecules interact mainly with the surface of the film to induce a solid-solid transition without noticeable swelling, dissolving or melting of the molecular material. © 2010 The Royal Society of Chemistry.

  17. Postshock Annealing of the Baszkówka Meteorite

    Science.gov (United States)

    Krzesińska, A.

    2012-09-01

    Chromite-plagioclase assemblages, native copper flanks and macroporosity are observed in the Baszkówka meteorite. Silicates however do not show crystal defects. Healed cracks testify on the annealing of their structure after strong shock event.

  18. Reinforcement Learning via Boltzmann Machines Implemented on Quantum Annealers

    Science.gov (United States)

    Levit, A.; Crawford, D.; Ronagh, P.; Oberoi, J.; Ghadermarzy, N.

    2016-12-01

    Recent studies have suggested promising application of quantum annealing devices as Boltzmann distribution samplers. We exploit this idea to develop a reinforcement learning framework using Boltzmann machines implemented on quantum annealing systems. We apply our method to find optimal policies in Markov decision processes. The evolution of the reinforcement learning algorithms relies on training a Neural Network. We use Quantum Monte-Carlo simulation of an associated network of qubits to provide experimental evidence of suitability of our approach.

  19. Improved mapping of the travelling salesman problem for quantum annealing

    Science.gov (United States)

    Troyer, Matthias; Heim, Bettina; Brown, Ethan; Wecker, David

    2015-03-01

    We consider the quantum adiabatic algorithm as applied to the travelling salesman problem (TSP). We introduce a novel mapping of TSP to an Ising spin glass Hamiltonian and compare it to previous known mappings. Through direct perturbative analysis, unitary evolution, and simulated quantum annealing, we show this new mapping to be significantly superior. We discuss how this advantage can translate to actual physical implementations of TSP on quantum annealers.

  20. Precise annealing of focal plane arrays for optical detection

    Energy Technology Data Exchange (ETDEWEB)

    Bender, Daniel A.

    2017-10-17

    Precise annealing of identified defective regions of a Focal Plane Array ("FPA") (e.g., exclusive of non-defective regions of the FPA) facilitates removal of defects from an FPA that has been hybridized and/or packaged with readout electronics. Radiation is optionally applied under operating conditions, such as under cryogenic temperatures, such that performance of an FPA can be evaluated before, during, and after annealing without requiring thermal cycling.

  1. Influence of phosphate esters on the annealing properties of starch

    DEFF Research Database (Denmark)

    Wischmann, Bente; Muhrbeck, Per

    1998-01-01

    The effects of annealing on native potato, waxy maize, and phosphorylated waxy maize starches were compared. Phosphorylated waxy maize starch responded to annealing in a manner between that of the naturally phosphorylated potato starch and that of the native waxy maize starch. The gelatinisation ....... It was concluded that the phosphate groups have similar effects as they do in the native, naturally phosphorylated potato starch, although the substitution pattern is not entirely the same in the artificially phosphorylated starch....

  2. Development and application of a quantitative loop-mediated isothermal amplification method for detecting genetically modified maize MON863.

    Science.gov (United States)

    Huang, Sicong; Xu, Yuancong; Yan, Xinghua; Shang, Ying; Zhu, Pengyu; Tian, Wenying; Xu, Wentao

    2015-01-01

    A SYBR Green I-based quantitative loop-mediated isothermal amplification (LAMP) assay was developed for the rapid detection of genetically modified maize MON863. A set of primers was designed based on the integration region of the Cry3Bb1 and tahsp17 genes. The qualitative and quantitative reaction conditions (dNTPs, betaine, primers, Mg(2+), Bst polymerase, temperature, reaction time) were optimized. The concentrations of Mg(2+) and betaine were found to be important to the LAMP assay. The detection limits of both qualitative and quantitative LAMP for MON863 were as low as 4 haploid genomic DNA, and the LAMP reactions can be completed within 1 h at an isothermal temperature of 65 °C. The results of this study demonstrate that this new SYBR Green I-based quantitative LAMP assay system is reliable, sensitive and accurate. © 2014 Society of Chemical Industry.

  3. Solubility and moisture sorption isotherms of whey-protein-based edible films as influenced by lipid and plasticizer incorporation.

    Science.gov (United States)

    Kim, S J; Ustunol, Z

    2001-09-01

    Plasticized whey-protein and whey-protein emulsion films were produced using sorbitol and glycerol as plasticizers and butterfat and candelilla wax as lipids. Protein, plasticizer, and lipid ratios were optimized to obtain acceptable free-standing flexible films. Water solubility (20 degrees C, 24 h) and moisture sorption isotherms (0.18-0.90 a(w), 25 degrees C) of the films were determined. The experimental moisture sorption isotherm values were fitted using the Guggenheim-Anderson-DeBoer (GAB) model. Solubility and equilibrium moisture contents (EMC) of the films were influenced by plasticizer and lipid incorporation. EMCs of all films increased rapidly at a(w) > or = 0.65. Incorporation of lipids reduced solubilities and EMCs of sorbitol- and glycerol-plasticized films. The effects of plasticizer and lipid type on GAB constants were also determined.

  4. Effect of Annealing Process on the Properties of Ni(55%)Cr(40%)Si(5%) Thin-Film Resistors.

    Science.gov (United States)

    Cheng, Huan-Yi; Chen, Ying-Chung; Li, Pei-Jou; Yang, Cheng-Fu; Huang, Hong-Hsin

    2015-10-02

    Resistors in integrated circuits (ICs) are implemented using diffused methods fabricated in the base and emitter regions of bipolar transistor or in source/drain regions of CMOS. Deposition of thin films on the wafer surface is another choice to fabricate the thin-film resistors in ICs' applications. In this study, Ni(55%)Cr(40%)Si(5%) (abbreviated as NiCrSi) in wt % was used as the target and the sputtering method was used to deposit the thin-film resistors on Al2O3 substrates. NiCrSi thin-film resistors with different thicknesses of 30.8 nm~334.7 nm were obtained by controlling deposition time. After deposition, the thin-film resistors were annealed at 400 °C under different durations in N₂ atmosphere using the rapid thermal annealing (RTA) process. The sheet resistance of NiCrSi thin-film resistors was measured using the four-point-probe method from 25 °C to 125 °C, then the temperature coefficient of resistance could be obtained. We aim to show that resistivity of NiCrSi thin-film resistors decreased with increasing deposition time (thickness) and the annealing process had apparent effect on the sheet resistance and temperature coefficient of resistance. We also aim to show that the annealed NiCrSi thin-film resistors had a low temperature coefficient of resistance (TCR) between 0 ppm/°C and +50 ppm/°C.

  5. Rapid construction of insulated genetic circuits via synthetic sequence-guided isothermal assembly

    OpenAIRE

    Torella, Joseph P.; Boehm, Christian R.; Lienert, Florian; Chen, Jan-Hung; Way, Jeffrey C.; Silver, Pamela A.

    2013-01-01

    In vitro recombination methods have enabled one-step construction of large DNA sequences from multiple parts. Although synthetic biological circuits can in principle be assembled in the same fashion, they typically contain repeated sequence elements such as standard promoters and terminators that interfere with homologous recombination. Here we use a computational approach to design synthetic, biologically inactive unique nucleotide sequences (UNSes) that facilitate accurate ordered assembly....

  6. Thermalization, Freeze-out, and Noise: Deciphering Experimental Quantum Annealers

    Science.gov (United States)

    Marshall, Jeffrey; Rieffel, Eleanor G.; Hen, Itay

    2017-12-01

    By contrasting the performance of two quantum annealers operating at different temperatures, we address recent questions related to the role of temperature in these devices and their function as "Boltzmann samplers." Using a method to reliably calculate the degeneracies of the energy levels of large-scale spin-glass instances, we are able to estimate the instance-dependent effective temperature from the output of annealing runs. Our results corroborate the "freeze-out" picture which posits two regimes, one in which the final state corresponds to a Boltzmann distribution of the final Hamiltonian with a well-defined "effective temperature" determined at a freeze-out point late in the annealing schedule, and another regime in which such a distribution is not necessarily expected. We find that the output distributions of the annealers do not, in general, correspond to a classical Boltzmann distribution for the final Hamiltonian. We also find that the effective temperatures at different programing cycles fluctuate greatly, with the effect worsening with problem size. We discuss the implications of our results for the design of future quantum annealers to act as more-effective Boltzmann samplers and for the programing of such annealers.

  7. Quantum versus simulated annealing in wireless interference network optimization

    Science.gov (United States)

    Wang, Chi; Chen, Huo; Jonckheere, Edmond

    2016-05-01

    Quantum annealing (QA) serves as a specialized optimizer that is able to solve many NP-hard problems and that is believed to have a theoretical advantage over simulated annealing (SA) via quantum tunneling. With the introduction of the D-Wave programmable quantum annealer, a considerable amount of effort has been devoted to detect and quantify quantum speedup. While the debate over speedup remains inconclusive as of now, instead of attempting to show general quantum advantage, here, we focus on a novel real-world application of D-Wave in wireless networking—more specifically, the scheduling of the activation of the air-links for maximum throughput subject to interference avoidance near network nodes. In addition, D-Wave implementation is made error insensitive by a novel Hamiltonian extra penalty weight adjustment that enlarges the gap and substantially reduces the occurrence of interference violations resulting from inevitable spin bias and coupling errors. The major result of this paper is that quantum annealing benefits more than simulated annealing from this gap expansion process, both in terms of ST99 speedup and network queue occupancy. It is the hope that this could become a real-word application niche where potential benefits of quantum annealing could be objectively assessed.

  8. Quantum versus simulated annealing in wireless interference network optimization.

    Science.gov (United States)

    Wang, Chi; Chen, Huo; Jonckheere, Edmond

    2016-05-16

    Quantum annealing (QA) serves as a specialized optimizer that is able to solve many NP-hard problems and that is believed to have a theoretical advantage over simulated annealing (SA) via quantum tunneling. With the introduction of the D-Wave programmable quantum annealer, a considerable amount of effort has been devoted to detect and quantify quantum speedup. While the debate over speedup remains inconclusive as of now, instead of attempting to show general quantum advantage, here, we focus on a novel real-world application of D-Wave in wireless networking-more specifically, the scheduling of the activation of the air-links for maximum throughput subject to interference avoidance near network nodes. In addition, D-Wave implementation is made error insensitive by a novel Hamiltonian extra penalty weight adjustment that enlarges the gap and substantially reduces the occurrence of interference violations resulting from inevitable spin bias and coupling errors. The major result of this paper is that quantum annealing benefits more than simulated annealing from this gap expansion process, both in terms of ST99 speedup and network queue occupancy. It is the hope that this could become a real-word application niche where potential benefits of quantum annealing could be objectively assessed.

  9. Thermal, quantum and simulated quantum annealing: analytical comparisons for simple models

    OpenAIRE

    Bapst, Victor; Semerjian, Guilhem

    2015-01-01

    We study various annealing dynamics, both classical and quantum, for simple mean-field models and explain how to describe their behavior in the thermodynamic limit in terms of differential equations. In particular we emphasize the differences between quantum annealing (i.e. evolution with Schr\\"odinger equation) and simulated quantum annealing (i.e. annealing of a Quantum Monte Carlo simulation).

  10. mediated isothermal amplification of the pat selectable marker gene

    African Journals Online (AJOL)

    ajl yemi

    2011-11-28

    Nov 28, 2011 ... *Corresponding author. E-mail: wuzhongyi@yahoo.com. Tel: 86-10-51503668; Fax: 86-10-51503980. Abbreviations: LAMP, Loop-mediated isothermal amplification;. PCR, polymerase chain reaction; FIP, forward inner primer;. BIP, backward inner primer; GMOs, genetically modified organisms; CTAB, cetyl ...

  11. Non-isothermal Moisture Transport Through Insulation Materials

    DEFF Research Database (Denmark)

    Peuhkuri, Ruut Hannele; Rode, Carsten; Hansen, Kurt Kielsgaard

    2008-01-01

    conclusions and therefore the question about existence of the type of transport forms driven by the non-isothermal effects remains open. Rather surprisingly, all the materials, including the almost non-hygroscopic materials (e.g. rock wool) and very hygroscopic materials (e.g. cellulose insulation) showed...

  12. Isothermal, kinetic and thermodynamic studies on basic dye sorption ...

    African Journals Online (AJOL)

    In this paper, a new cation sorbent, which bore carboxyl and hydroxyl groups of tartaric acid (TA) derived from esterified wheat straw (EWS), was originally prepared by solid phase thermochemistry method. The isotherm, kinetics and thermodynamics of basic dye sorptions from aqueous solution onto EWS were investigated ...

  13. Water Sorption Isotherm Characteristics of Seeds of Six Indigenous ...

    African Journals Online (AJOL)

    Water Sorption Isotherm Characteristics of Seeds of Six Indigenous Forest Tree Species in Ghana. ... West African Journal of Applied Ecology ... The relationship between storage temperature, relative humidity and seed water content was investigated for six indigenous forest tree seed species, namely Garcinia kola, ...

  14. ISOTHERMAL AND THERMOMECHANICAL FATIGUE OF A NICKEL-BASE SUPERALLOY

    Directory of Open Access Journals (Sweden)

    Carlos Carvalho Engler-Pinto Júnior

    2014-06-01

    Full Text Available Thermal gradients arising during transient regimes of start-up and shutdown operations produce a complex thermal and mechanical fatigue loading which limits the life of turbine blades and other engine components operating at high temperatures. More accurate and reliable assessment under non-isothermal fatigue becomes therefore mandatory. This paper investigates the nickel base superalloy CM 247LC-DS under isothermal low cycle fatigue (LCF and thermomechanical fatigue (TMF. Test temperatures range from 600°C to 1,000°C. The behavior of the alloy is strongly affected by the temperature variation, especially in the 800°C-1,000°C range. The Ramberg-Osgood equation fits very well the observed isothermal behavior for the whole temperature range. The simplified non-isothermal stress-strain model based on linear plasticity proposed to represent the thermo-mechanical fatigue behavior was able to reproduce the observed behavior for both in-phase and out-of-phase TMF cycling.

  15. Isothermal martensite formation at sub-zero temperatures

    DEFF Research Database (Denmark)

    Stojko, Allan; Hansen, Mikkel Fougt; Slycke, Jan

    2012-01-01

    Sub-zero treatment of steels with an Mf below 0°C relies (partly) on a continuation of the martensite formation. The present work reports on the observation of isothermal martensite formation in the sub-zero temperature regime for two steels: AISI 1070 and AISI 52100. Samples were austenitized...

  16. LES of droplet-laden non-isothermal channel flow

    NARCIS (Netherlands)

    Michalek, W.R.; Liew, R.; Kuerten, Johannes G.M.; Zeegers, J.C.H.

    In this paper subgrid models for LES of droplet-laden non-isothermal channel flow are tested and improved for three Reynolds numbers based on friction velocity, Reτ of 150, 395, and 950 with the aim to develop a simulation method for LES of a droplet-laden Ranque-Hilsch vortex tube. A new subgrid

  17. Whole genome amplification: Use of advanced isothermal method

    African Journals Online (AJOL)

    Yomi

    2010-12-29

    Dec 29, 2010 ... Whole genome amplification: Use of advanced isothermal method. Sima Moghaddaszadeh Ahrabi1, Safar Farajnia2,3*, Ghodratollah Rahimi-Mianji4, Soheila. Montazer Saheb3 ... Moreover, application of high fidelity and high possessive DNA ..... between I-PEP with MDA by using serial dilutions of.

  18. Speeds of sound and isothermal compressibility of ternary liquid ...

    Indian Academy of Sciences (India)

    Isentropic compressibility has been widely used to study the molecular interactions through its excess value. On the other hand, it can also be used to deduce other useful thermodynamic properties such as isothermal compressibility (βT ), heat capacity ratio (γ), internal pressure (pi) and cohesive energy density (CED).

  19. Adsorption isotherms and kinetics for dibenzothiophene on activated ...

    Indian Academy of Sciences (India)

    energy-dispersive X-ray spectroscopy, field-emission transmission electron microscopy, X-ray diffraction and X-ray photoelectron spectrometre. Adsorption isotherms were obtained and desulphurization kinetics were carried out on solutions of dibenzothiophene (DBT) and thiophene in a model fuel. The efficiencies of DBT ...

  20. Isothermal, kinetic and thermodynamic studies on basic dye sorption ...

    African Journals Online (AJOL)

    PRECIOUS

    2009-12-15

    Dec 15, 2009 ... Full Length Research Paper. Isothermal, kinetic and thermodynamic studies on ... al., 2008), castor seed shell (Oladoja et al., 2008), coffee husk (Oliveira et al., 2008), neem leaf powder (Tahir et ... length and washed with tap water to remove soil and dust and then dried overnight at 50°C. Dried wheat straw ...

  1. Water adsorption isotherms and thermodynamic properties of cassava bagasse

    Energy Technology Data Exchange (ETDEWEB)

    Polachini, Tiago Carregari, E-mail: tiagopolachini@terra.com.br; Betiol, Lilian Fachin Leonardo; Lopes-Filho, José Francisco; Telis-Romero, Javier

    2016-05-20

    Highlights: • Adsorption isotherms and composition of cassava bagasse were determined. • GAB equation was the best-fitted model to sorption data of type II isotherm. • Isosteric heat of sorption was calculated in a range of equilibrium moisture content. • Differential enthalpy and entropy confirmed the isokinetic compensation theory. • Water adsorption by cassava bagasse is considered an enthalpy driven process. - Abstract: Losses of food industry are generally wet products that must be dried to posterior use and storage. In order to optimize drying processes, the study of isotherms and thermodynamic properties become essential to understand the water sorption mechanisms of cassava bagasse. For this, cassava bagasse was chemically analyzed and had its adsorption isotherms determined in the range of 293.15–353.15 K through the static gravimetric method. The models of GAB, Halsey, Henderson, Oswin and Peleg were fitted, and best adjustments were found for GAB model with R{sup 2} > 0.998 and no pattern distribution of residual plots. Isosteric heat of adsorption and thermodynamic parameters could be determined as a function of moisture content. Compensation theory was confirmed, with linear relationship between enthalpy and entropy and higher values of isokinetic temperature (T{sub B} = 395.62 K) than harmonic temperature. Water adsorption was considered driven by enthalpy, clarifying the mechanisms of water vapor sorption in cassava bagasse.

  2. Isotherm, kinetic, and thermodynamic study of ciprofloxacin sorption on sediments.

    Science.gov (United States)

    Mutavdžić Pavlović, Dragana; Ćurković, Lidija; Grčić, Ivana; Šimić, Iva; Župan, Josip

    2017-04-01

    In this study, equilibrium isotherms, kinetics and thermodynamics of ciprofloxacin on seven sediments in a batch sorption process were examined. The effects of contact time, initial ciprofloxacin concentration, temperature and ionic strength on the sorption process were studied. The K d parameter from linear sorption model was determined by linear regression analysis, while the Freundlich and Dubinin-Radushkevich (D-R) sorption models were applied to describe the equilibrium isotherms by linear and nonlinear methods. The estimated K d values varied from 171 to 37,347 mL/g. The obtained values of E (free energy estimated from D-R isotherm model) were between 3.51 and 8.64 kJ/mol, which indicated a physical nature of ciprofloxacin sorption on studied sediments. According to obtained n values as measure of intensity of sorption estimate from Freundlich isotherm model (from 0.69 to 1.442), ciprofloxacin sorption on sediments can be categorized from poor to moderately difficult sorption characteristics. Kinetics data were best fitted by the pseudo-second-order model (R 2  > 0.999). Thermodynamic parameters including the Gibbs free energy (ΔG°), enthalpy (ΔH°) and entropy (ΔS°) were calculated to estimate the nature of ciprofloxacin sorption. Results suggested that sorption on sediments was a spontaneous exothermic process.

  3. On the calculation of disjoining pressure isotherms for nonaqueous films.

    Science.gov (United States)

    Correa, Rafael; Saramago, Benilde

    2004-02-15

    A review of the methods of London and Hamaker and of Lifshitz for calculating disjoining pressure isotherms of nonaqueous liquid films is presented. The disjoining pressure isotherms for films of n-octane and of three triglycerides (tributyrin, tricaprylin, and triolein) on glass were calculated using both methods. The disjoining pressure isotherms for films on silanized glass were calculated using only the London-Hamaker approach. The refractive indices and static dielectric constants, necessary for the calculations, were measured. The silanized glass was considered to be the original glass covered by a layer with the same characteristic frequency as the underlying glass and a smaller limiting value of the dielectric constant epsilon(0). The limiting dielectric constant epsilon(0) and the thickness of the surface layer were taken as adjustable parameters. The disjoining pressure isotherms indicate that all films are stable on glass. In contrast, the stability of the films formed on silanized glass was found to depend mainly on the value of epsilon(0) and, less strongly, on the thickness of the surface layer. The stability of the films decreased with the decrease of epsilon(0) and, for each value of epsilon(0), was maximal for the thinnest surface layer.

  4. Development and application of a loop-mediated isothermal ...

    African Journals Online (AJOL)

    Haemophilus parasuis is the causative agent of Glässer's disease that has received much attention recently, due to the increasing economic losses this disease inflicts upon the pig industry worldwide. In this study, loop-mediated isothermal amplification method (LAMP) methodology was designed for diagnosing H.

  5. Non-isothermal gas absorption with reversible chemical reaction

    NARCIS (Netherlands)

    Vas Bhat, R.D.; Swaaij, W.P.M. van; Benes, N.E.; Kuipers, J.A.M.; Versteeg, G.F.

    1997-01-01

    A fundamental description of non-isothermal mass transfer accompanied by a single reversible chemical reaction has been presented. The description is based on the Higbie penetration theory. Arrhenius type dependence of solubility, reaction rates and diffusivities on temperature has been assumed.

  6. Non-isothermal gas absorption with reversible chemical reaction.

    NARCIS (Netherlands)

    Vas bhat, R.D.; van Swaaij, Willibrordus Petrus Maria; Benes, Nieck Edwin; Kuipers, J.A.M.; Versteeg, Geert

    1997-01-01

    A fundamental description of non-isothermal mass transfer accompanied by a single reversible chemical reaction has been presented. The description is based on the Higbie penetration theory. Arrhenius type dependence of solubility, reaction rates and diffusivities on temperature has been assumed.

  7. Isothermal Titration Calorimetry Can Provide Critical Thinking Opportunities

    Science.gov (United States)

    Moore, Dale E.; Goode, David R.; Seney, Caryn S.; Boatwright, Jennifer M.

    2016-01-01

    College chemistry faculties might not have considered including isothermal titration calorimetry (ITC) in their majors' curriculum because experimental data from this instrumental method are often analyzed via automation (software). However, the software-based data analysis can be replaced with a spreadsheet-based analysis that is readily…

  8. Effect of gamma irradiation on moisture sorption isotherms of cowpeas

    African Journals Online (AJOL)

    The effect of gamma irradiation on moisture sorption isotherms of cowpeas was investigated The nonirradiated and irradiated cowpeas exhibited the typical three stage sigmoidal curve found in most foods. There was also a concomitant increase in the equilibrium moisture content (EMC) as relative humidity increased for ...

  9. Annealing effects on strain and stress sensitivity of polymer optical fibre based sensors

    DEFF Research Database (Denmark)

    Pospori, A.; Marques, C. A. F.; Zubel, M. G.

    2016-01-01

    The annealing effects on strain and stress sensitivity of polymer optical fibre Bragg grating sensors after their photoinscription are investigated. PMMA optical fibre based Bragg grating sensors are first photo-inscribed and then they were placed into hot water for annealing. Strain, stress...... and force sensitivity measurements are taken before and after annealing. Parameters such as annealing time and annealing temperature are investigated. The change of the fibre diameter due to water absorption and the annealing process is also considered. The results show that annealing the polymer optical...

  10. Loop-mediated isothermal amplification (LAMP) based detection of Colletotrichum falcatum causing red rot in sugarcane.

    Science.gov (United States)

    Chandra, Amaresh; Keizerweerd, Amber T; Que, Youxiong; Grisham, Michael P

    2015-08-01

    Red rot, caused by Colletotrichum falcatum, is a destructive disease prevalent in most sugarcane-producing countries. Disease-free sugarcane planting materials (setts) are essential as the pathogen spreads primarily through infected setts. The present study was undertaken to develop a loop-mediated isothermal amplification (LAMP) assay for the detection of C. falcatum. C. falcatum genomic DNA was isolated from pure mycelium culture and infected tissues. Four sets of primers corresponding to a unique DNA sequence specific to C. falcatum were designed. Specificity of the LAMP test was checked with DNA of another fungal pathogen of sugarcane, Puccinia melanocephala, as well as two closely-related species, Colletotrichum fructivorum and Colletotrichum acutatum. No reaction was found with the three pathogens. When C. falcatum DNA from pure culture was used in a detection limit analysis, sensitivity of the LAMP method was observed to be ten times higher than that of conventional PCR; however, sensitivity was only 5 times higher when DNA from C. falcatum-infected tissues was used. Using the LAMP assay, C. falcatum DNA is amplified with high specificity, efficiency, and rapidity under isothermal conditions. Moreover, visual judgment of color change in <1 h without further post-amplification processing makes the LAMP method convenient, economical, and useful in diagnostic laboratories and the field.

  11. Investigation of aerodynamic structure of isothermal swirl flow in a two-stage burner

    Science.gov (United States)

    Yusupov, R. R.; Krasinsky, D. V.; Shtork, S. I.

    2017-09-01

    The work is devoted to experimental and numerical study of aerodynamic structure of a swirl flow in isothermal model of a vortex burner device that is characterized by the fluid flow supply via two sequentially-mounted tangential swirlers. Depending on the way of the flow supply into the second-stage swirler, either co-swirl or counter-swirl of two flows can be realized. The effect of the second-stage supply direction on the resulting aerodynamic structure has been investigated. Using LDA measurement system the profiles of averaged axial and tangential velocity components were obtained. Experiments have shown that in the co-swirl case the flow inside the vortex burner model is characterized by strong non-uniformity, while in the counter-swirl regime a rapid mixing of the flows from the first and second stages occurs, resulting in a uniform distribution of the flow across the chamber section. Numerical simulation of 3D isothermal turbulent flow has been performed for the counter-swirl regime using the differential Reynolds stress model in the time-dependent formulation. Using the Q-criterion for the identification of vortices in numerical data arrays, the evolution of large-scale vortex structures of the swirl flow inside the vortex chamber has been visualized, indicating the presence of two spiral-shape vortex filaments in the vortex chamber. The periodic character of dynamics of these vortex structures has been revealed.

  12. Temperature stability of proteins: Analysis of irreversible denaturation using isothermal calorimetry.

    Science.gov (United States)

    Schön, Arne; Clarkson, Benjamin R; Jaime, Maria; Freire, Ernesto

    2017-11-01

    The structural stability of proteins has been traditionally studied under conditions in which the folding/unfolding reaction is reversible, since thermodynamic parameters can only be determined under these conditions. Achieving reversibility conditions in temperature stability experiments has often required performing the experiments at acidic pH or other nonphysiological solvent conditions. With the rapid development of protein drugs, the fastest growing segment in the pharmaceutical industry, the need to evaluate protein stability under formulation conditions has acquired renewed urgency. Under formulation conditions and the required high protein concentration (∼100 mg/mL), protein denaturation is irreversible and frequently coupled to aggregation and precipitation. In this article, we examine the thermal denaturation of hen egg white lysozyme (HEWL) under irreversible conditions and concentrations up to 100 mg/mL using several techniques, especially isothermal calorimetry which has been used to measure the enthalpy and kinetics of the unfolding and aggregation/precipitation at 12°C below the transition temperature measured by DSC. At those temperatures the rate of irreversible protein denaturation and aggregation of HEWL is measured to be on the order of 1 day-1 . Isothermal calorimetry appears a suitable technique to identify buffer formulation conditions that maximize the long term stability of protein drugs. © 2017 Wiley Periodicals, Inc.

  13. Thermal stability and non-isothermal crystallization kinetics of Pd82Si18 amorphous ribbon

    Science.gov (United States)

    Wang, Xutong; Zeng, Mo; Nollmann, Niklas; Wilde, Gerhard; Wang, Jiang; Tang, Chengying

    2017-06-01

    Rapidly quenched Pd82Si18 ribbon was prepared by melt spinning. The thermal stability and non-isothermal crystallization kinetics of Pd82Si18 amorphous ribbon were investigated by differential scanning calorimeter measurements. Its structure was investigated by X-ray diffraction and transmission electronic microscopy. The activation energy was calculated by the Kissinger method, and the nucleation and growth during non-isothermal crystallization were investigated by the local activation energy and local Avrami exponent. The average activation energy for Pd82Si18 amorphous ribbon based on the Kissinger method is 330.672 kJ/mol, indicating that it has high thermal stability. The local activation energy of the glass ribbon was determined by the Kissinger-Akahira-Sunose method, and the local Avrami exponent was obtained based on the Johnson-Mehl-Avrami model. The calculated local activation energy increases to a maximum when the crystallization column fraction reaches 0.3, and it then decreases, which shows that crystallization is a multistep process. The local Avrami exponent indicates that the crystallization process of Pd82Si18 amorphous ribbon is controlled by volume nucleation with three-dimensional growth at various nucleation rates.

  14. Thermal stability and non-isothermal crystallization kinetics of Pd82Si18 amorphous ribbon

    Directory of Open Access Journals (Sweden)

    Xutong Wang

    2017-06-01

    Full Text Available Rapidly quenched Pd82Si18 ribbon was prepared by melt spinning. The thermal stability and non-isothermal crystallization kinetics of Pd82Si18 amorphous ribbon were investigated by differential scanning calorimeter measurements. Its structure was investigated by X-ray diffraction and transmission electronic microscopy. The activation energy was calculated by the Kissinger method, and the nucleation and growth during non-isothermal crystallization were investigated by the local activation energy and local Avrami exponent. The average activation energy for Pd82Si18 amorphous ribbon based on the Kissinger method is 330.672 kJ/mol, indicating that it has high thermal stability. The local activation energy of the glass ribbon was determined by the Kissinger–Akahira–Sunose method, and the local Avrami exponent was obtained based on the Johnson–Mehl–Avrami model. The calculated local activation energy increases to a maximum when the crystallization column fraction reaches 0.3, and it then decreases, which shows that crystallization is a multistep process. The local Avrami exponent indicates that the crystallization process of Pd82Si18 amorphous ribbon is controlled by volume nucleation with three-dimensional growth at various nucleation rates.

  15. GMO detection in food and feed through screening by visual loop-mediated isothermal amplification assays.

    Science.gov (United States)

    Wang, Cong; Li, Rong; Quan, Sheng; Shen, Ping; Zhang, Dabing; Shi, Jianxin; Yang, Litao

    2015-06-01

    Isothermal DNA/RNA amplification techniques are the primary methodology for developing on-spot rapid nucleic acid amplification assays, and the loop-mediated isothermal amplification (LAMP) technique has been developed and applied in the detection of foodborne pathogens, plant/animal viruses, and genetically modified (GM) food/feed contents. In this study, one set of LAMP assays targeting on eight frequently used universal elements, marker genes, and exogenous target genes, such as CaMV35S promoter, FMV35S promoter, NOS, bar, cry1Ac, CP4 epsps, pat, and NptII, were developed for visual screening of GM contents in plant-derived food samples with high efficiency and accuracy. For these eight LAMP assays, their specificity was evaluated by testing commercial GM plant events and their limits of detection were also determined, which are 10 haploid genome equivalents (HGE) for FMV35S promoter, cry1Ac, and pat assays, as well as five HGE for CaMV35S promoter, bar, NOS terminator, CP4 epsps, and NptII assays. The screening applicability of these LAMP assays was further validated successfully using practical canola, soybean, and maize samples. The results suggested that the established visual LAMP assays are applicable and cost-effective for GM screening in plant-derived food samples.

  16. Loop Mediated Isothermal Amplification (LAMP): A Versatile Technique for Detection of Microorganisms.

    Science.gov (United States)

    Wong, Yien-Ping; Othman, Shuhaidah; Lau, Yee-Ling; Son, Radu; Chee, Hui-Yee

    2017-11-22

    Loop mediated isothermal amplification (LAMP) amplifies DNA with high specificity, efficiency, and rapidity under isothermal conditions by using a DNA polymerase with high displacement strand activity and a set of specifically designed primers to amplify targeted DNA strands. Following its first discovery by Notomi et al. in the year 2000, LAMP was further developed over the years which involved the combination of this technique with other molecular approaches, such as reverse transcription and multiplex amplification for the detection of infectious diseases caused by microorganisms in humans, livestock and plants. In this review, available types of LAMP techniques will be discussed together with their applications in detection of various microorganisms'. Up to date, there are varieties of LAMP detection methods available including colorimetric and fluorescent detection, real-time monitoring using turbidity meter and detection using lateral flow device which will also be highlighted in this review. Apart from that, commercialization of LAMP technique had also been reported such as lyophilized form of LAMP reagents kit and LAMP primer sets for detection of pathogenic microorganisms. On top of that, advantages and limitations of this molecular detection method are also described together with its future potential as a diagnostic method for infectious disease. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  17. Determination of competitive adsorption isotherm of enantiomers on preparative chromatographic columns using inverse method.

    Science.gov (United States)

    Xu, Jin; Zhu, Lei; Xu, Guoqian; Yu, Weifang; Ray, Ajar K

    2013-01-18

    Precise determination of competitive adsorption isotherm is of great importance for model-based optimization and scale-up of chromatographic separation processes, particularly for the simulated moving bed (SMB) systems due to its intrinsic complexity. In this study, five parameters of a bi-Langmuir model for adsorption of ketoprofen enantiomers on a preparative Chiralpak AD column at 25°C were determined by the application of inverse method (IM). Transport-dispersive (TD) model parameters, axial dispersion and mass transfer coefficients were independently estimated first by tuning a series of linear pulse experiments. Competitive adsorption isotherm model parameters were then determined independently by fitting the experimental data. A new numerical scheme that couples non-dominated sorting genetic algorithm (NSGA) and Levenberg-Marquardt algorithm (LMA) was proposed for the data fitting. NSGA was capable of rapidly locating the optimal solution in the parametric space while LGA allowed speedy convergence given a good initial guess. Independently measured band profiles and simulated moving bed (SMB) experiments were later used to validate the model parameters. The experimental results were in good agreement with the model predictions. Copyright © 2012 Elsevier B.V. All rights reserved.

  18. Magnetic vinylphenyl boronic acid microparticles for Cr(VI) adsorption: Kinetic, isotherm and thermodynamic studies

    Energy Technology Data Exchange (ETDEWEB)

    Kara, Ali, E-mail: akara@uludag.edu.tr [Uludag University, Faculty of Arts and Science, Department of Chemistry, 16059 Bursa (Turkey); Demirbel, Emel [Uludag University, Faculty of Arts and Science, Department of Chemistry, 16059 Bursa (Turkey); Tekin, Nalan [Kocaeli University, Faculty of Arts and Science, Department of Chemistry, 41380 Kocaeli (Turkey); Osman, Bilgen; Beşirli, Necati [Uludag University, Faculty of Arts and Science, Department of Chemistry, 16059 Bursa (Turkey)

    2015-04-09

    Highlights: • Cr(VI) can oxidize biological molecules and be one of the most harmful substance. • Magnetic seperation techniques are used on different applications in many fields. • Magnetic systems can be used for rapid and selective removal as a magnetic processor. • We investigate properties of both new material and other magnetic adsorbents reported in the literatures on the adsorption of Cr(VI) ions. • No researchments were reported on adsorption of Cr(VI) with magnetic vinylphenyl boronic acid microparticles. - Abstract: Magnetic vinylphenyl boronic acid microparticles, poly(ethylene glycol dimethacrylate(EG)–vinylphenyl boronic acid(VPBA)) [m-poly(EG–VPBA)], produced by suspension polymerization and characterized, was found to be an efficient solid polymer for Cr(VI) adsorption. The m-poly(EG–VPBA) microparticles were prepared by copolymerizing of ethylene glycol dimethylacrylate (EG) with 4-vinyl phenyl boronic acid (VPBA). The m-poly(EG–VPBA) microparticles were characterized by N{sub 2} adsorption/desorption isotherms, electron spin resonance (ESR), X-ray diffraction (XRD), fourier transform infrared spectroscopy (FTIR), thermal gravimetric analysis (TGA), elemental analysis, scanning electron microscope (SEM) and swelling studies. The m-poly(EG–VPBA) microparticles were used at adsorbent/Cr(VI) ion ratios. The influence of pH, Cr(VI) initial concentration, temperature of the removal process was investigated. The maximum removal of Cr(VI) was observed at pH 2. Langmuir isotherm and Dubinin–Radushkvich isotherm were found to better fit the experiment data rather than Fruendlich isotherm. The kinetics of the adsorption process of Cr(VI) on the m-poly(EG–VPBA) microparticles were investigated using the pseudo first-order, pseudo-second-order, Ritch-second-order and intraparticle diffusion models, results showed that the pseudo-second order equation model provided the best correlation with the experimental results. The thermodynamic

  19. High-density Bi-Pb-Sr-Ca-Cu-O superconductor prepared by rapid thermal melt processing

    Energy Technology Data Exchange (ETDEWEB)

    Moon, B.M.; Lalevic, B. (Department of Electrical and Computer Engineering, Rutgers, The State University of New Jersey, P. O. Box 909, Piscataway, New Jersey 08855-0909 (US)); Kear, B.H.; McCandlish, L.E. (Department of Mechanics and Materials Science, Rutgers, The State University of New Jersey, P. O. Box 909, Piscataway, New Jersey 08855-0909); Safari, A.; Meskoob, M. (Department of Ceramic Science and Engineering, Rutgers, The State University of New Jersey, P. O. Box 909, Piscataway, New Jersey 08855-0909)

    1989-10-02

    A high quality, dense Bi-Pb-Sr-Ca-Cu-O superconductor has been successfully synthesized by rapid thermal melt processing. Conventionally sintered pellets were melted at 1200 {degree}C, cooled rapidly, and then annealed. As-melted samples exhibited semiconductor behavior, which upon annealing became superconducting at 115 K ({ital T}{sub {ital c}}(zero)=105 K). A detailed study of various processing techniques has been carried out.

  20. High-density Bi-Pb-Sr-Ca-Cu-O superconductor prepared by rapid thermal melt processing

    Science.gov (United States)

    Moon, B. M.; Lalevic, B.; Kear, B. H.; McCandlish, L. E.; Safari, A.; Meskoob, M.

    1989-10-01

    A high quality, dense Bi-Pb-Sr-Ca-Cu-O superconductor has been successfully synthesized by rapid thermal melt processing. Conventionally sintered pellets were melted at 1200 °C, cooled rapidly, and then annealed. As-melted samples exhibited semiconductor behavior, which upon annealing became superconducting at 115 K [Tc(zero)=105 K]. A detailed study of various processing techniques has been carried out.