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Sample records for low-angle silicon-sheet growth method

  1. Development of advanced methods for continuous Czochralski growth. Silicon sheet growth development for the large area silicon sheet task of the low cost silicon solar array project

    Science.gov (United States)

    Wolfson, R. G.; Sibley, C. B.

    1978-01-01

    The three components required to modify the furnace for batch and continuous recharging with granular silicon were designed. The feasibility of extended growth cycles up to 40 hours long was demonstrated by a recharge simulation experiment; a 6 inch diameter crystal was pulled from a 20 kg charge, remelted, and pulled again for a total of four growth cycles, 59-1/8 inch of body length, and approximately 65 kg of calculated mass.

  2. Effects of transverse temperature field nonuniformity on stress in silicon sheet growth

    Science.gov (United States)

    Mataga, P. A.; Hutchinson, J. W.; Chalmers, B.; Bell, R. O.; Kalejs, J. P.

    1987-01-01

    Stress and strain rate distributions are calculated using finite element analysis for steady-state growth of thin silicon sheet temperature nonuniformities imposed in the transverse (sheet width) dimension. Significant reductions in residual stress are predicted to occur for the case where the sheet edge is cooled relative to its center provided plastic deformation with high creep rates is present.

  3. The Effect of Creep on the Residual Stresses Generated During Silicon Sheet Growth

    Science.gov (United States)

    Hutchinson, J. W.; Lambropoulos, J. C.

    1984-01-01

    The modeling of stresses generated during the growth of thin silicon sheets at high speeds is an important part of the EFG technique since the experimental measurement of the stresses is difficult and prohibitive. The residual stresses which arise in such a growth process lead to serious problems which make thin Si ribbons unsuitable for fabrication. The constitutive behavior is unrealistic because at high temperature (close to the melting point) Si exhibits considerable creep which significantly relaxes the residual stresses. The effect of creep on the residual stresses generated during the growth of Si sheets at high speeds was addressed and the basic qualitative effect of creep are reported.

  4. Continuous Czochralski growth: Silicon sheet growth development of the large area silicon sheet task of the Low Cost Silicon Solar Array project

    Science.gov (United States)

    1978-01-01

    The primary objective of this contract is to develop equipment and methods for the economic production of single crystal ingot material by the continuous Czochralski (CZ) process. Continuous CZ is defined for the purpose of this work as the growth of at least 100 kilograms of ingot from only one melt container. During the reporting period (October, 1977 - September, 1978), a modified grower was made fully functional and several recharge runs were performed. The largest run lasted 44 hours and over 42 kg of ingot was produced. Little, if any, degradation in efficiency was observed as a result of pulling multiple crystals from one crucible. Solar efficiencies observed were between 9.3 and 10.4% AMO (13.0 and 14.6% AMI) compared to 10.5% (14.7% AMI) for optimum CZ material control samples. Using the SAMICS/IPEG format, economic analysis of continuous CZ suggests that 1986 DoE cost goals can only be met by the growth of large diameter, large mass crystals.

  5. Continuous Czochralski Growth. Silicon Sheet Growth Development of the Large Area Silicon Sheet Task of the Low Cost Silicon Solar Array Project

    Science.gov (United States)

    Merz, F.

    1979-01-01

    During the reporting period, a successful 100 kilogram run was performed. Six ingots of 13 cm diameter were grown, ranging in size from 15.5 kg to 17.7 kg. Melt replenishment methods included both poly rod and lump feed material. Samples from each ingot were prepared for solar cell fabrication and analyses, impurity analysis, and structural studies. The furnace was converted to the 14-inch hot zone and preliminary heat runs were performed. Two sucessful runs were demonstrated, by growing 25 kg ingots from 30 kg melts. Also, a 100 kg run was attempted, utilizing the 14 inch crucible hot zone, but was prematurely terminated due to excessive monoxide which accumulated on the viewports and a seed failure.

  6. LSA Large Area Silicon Sheet Task. Continuous Liquid Feed Czochralski Growth. [for solar cell fabrication

    Science.gov (United States)

    Fiegl, G.

    1979-01-01

    The design and development of equipment and processes to demonstrate continuous growth of crystals by the Czochralski method suitable for producing single silicon crystals for use in solar cells is presented. The growth of at least 150 kg of mono silicon crystal, 150 mm in diameter is continuous from one growth container. A furnace with continuous liquid replenishment of the growth crucible, accomplished by a meltdown system with a continuous solid silicon feed mechanism and a liquid transfer system, with associated automatic feedback controls is discussed. Due to the silicon monoxide build up in the furnace and its retarding effect on crystal growth the furnace conversion for operation in the low pressure range is described. Development of systems for continuous solid recharging of the meltdown chamber for various forms of poly silicon is described.

  7. LSA Large Area Silicon Sheet Task Continuous Liquid Feed Czochralski Growth

    Science.gov (United States)

    Fiegl, G.

    1979-01-01

    A process for the continuous growth of crystals by the Czochralski method, suitable for producing single silicon crystals for use in solar cells was studied. Continuous growth is the growth of 100 Kg of single silicon crystals, 10 cm in diameter, from one container. A furnace with continuous liquid replenishment of the growth crucible, accomplished by a melt-down system and a liquid transfer mechanism, with associated automatic feedback controls was developed. Elements of the transfer system were further developed and tested during actual transfer runs. Considerable simplification of the heating element of the transfer tube was achieved. Accuracy and reliability of the temperature sensor, which is part of the power input control system for the transfer tube, was improved. Electrical and thermal effectiveness were increased while assembly of the transfer tube system was further simplified.

  8. Large Area Silicon Sheet by EFG. [quality control and productivity of edge-defined film-fed growth of ribbons

    Science.gov (United States)

    1979-01-01

    Influences on ribbon quality which might be caused by various materials of construction which are used in the growth furnace were assessed. At the present level of ribbon quality, which has produced 8.5% to 9.5% efficient solar cells, no particular influence of any furnace part was detected. The experiments led to the suspicion that the general environment and the somewhat unoptimized materials handling procedures might be responsible for the current variations in ribbon quality and that, therefore, continuous work with this furnace under rather more stringent environmental conditions and operating procedures could perhaps improve materials quality to some extent. The work on the multiple furnace was continued with two multiple growth runs being performed. In these runs, the melt replenishment system performed poorly and extensive modifications to it were designed to make reliable melt feeding for five ribbon growth possible. Additional characterization techniques for wide ribbons, stress measurements, and growth dynamics experiments are reported.

  9. Laser-zone Growth in a Ribbon-to-ribbon (RTR) Process Silicon Sheet Growth Development for the Large Area Silicon Sheet Task of the Low Cost Solar Array Project

    Science.gov (United States)

    Baghdadi, A.; Gurtler, R. W.; Legge, R.; Sopori, B.; Rice, M. J.; Ellis, R. J.

    1979-01-01

    A technique for growing limited-length ribbons continually was demonstrated. This Rigid Edge technique can be used to recrystallize about 95% of the polyribbon feedstock. A major advantage of this method is that only a single, constant length silicon ribbon is handled throughout the entire process sequence; this may be accomplished using cassettes similar to those presently in use for processing Czochralski waters. Thus a transition from Cz to ribbon technology can be smoothly affected. The maximum size being considered, 3 inches x 24 inches, is half a square foot, and will generate 6 watts for 12% efficiency at 1 sun. Silicon dioxide has been demonstrated as an effective, practical diffusion barrier for use during the polyribbon formation.

  10. Flat-plate solar array project. Volume 3: Silicon sheet: Wafers and ribbons

    Science.gov (United States)

    Briglio, A.; Dumas, K.; Leipold, M.; Morrison, A.

    1986-01-01

    The primary objective of the Silicon Sheet Task of the Flat-Plate Solar Array (FSA) Project was the development of one or more low cost technologies for producing silicon sheet suitable for processing into cost-competitive solar cells. Silicon sheet refers to high purity crystalline silicon of size and thickness for fabrication into solar cells. Areas covered in the project were ingot growth and casting, wafering, ribbon growth, and other sheet technologies. The task made and fostered significant improvements in silicon sheet including processing of both ingot and ribbon technologies. An additional important outcome was the vastly improved understanding of the characteristics associated with high quality sheet, and the control of the parameters required for higher efficiency solar cells. Although significant sheet cost reductions were made, the technology advancements required to meet the task cost goals were not achieved.

  11. Orientation and Morphology Effects in Rapid Silicon Sheet Solidification

    Science.gov (United States)

    Ciszek, T. F.

    1984-01-01

    Radial growth anisotropies and equilibrium forms of point nucleated, dislocation free silicon sheets spreading horizontally on the free surface of a silicon melt were measured for (100), (110), (111), and (112) sheet planes. The growth process was recorded. Qualitative Wulff surface free energy polar plots were deduced from the equilibrium shapes for each sheet plane. Predicted geometries for the tip shape of unidirectional, dislocation free, horizontally grown sheets growing in various directions within the planes were analyzed. Polycrystalline sheets and dendrite propagation were analyzed. For dendrites, growth rates on the order of 2.5 m/min and growth rate anisotropies of 25 are measured.

  12. Continuous Czochralski growth: Silicon sheet growth development of the large area sheet task of the low cost silicon solar array project

    Science.gov (United States)

    Johnson, C. M.

    1980-12-01

    The growth of 100 kg of silicon single crystal material, ten cm in diameter or greater, and 150 kg of silicon single crystal material 15 cm or greater utilizing one common silicon container material (one crucible) is investigated. A crystal grower that is recharged with a new supply of polysilicon material while still under vacuum and at temperatures above the melting point of silicon is developed. It accepts large polysilicon charges up to 30 kg, grows large crystal ingots (to 15 cm diameter and 25 kg in weight), and holds polysilicon material for recharging (rod or lump) while, at the same time, growing crystal ingots. Special equipment is designed to recharge polysilicon rods, recharge polysilicon lumps, and handle and store large, hot silicon crystal ingots. Many continuous crystal growth runs were performed lasting as long as 109 hours and producing as many as ten crystal ingots, 15 cm with weights progressing to 27 kg.

  13. Hydrogen passivation of silicon sheet solar cells

    International Nuclear Information System (INIS)

    Tsuo, Y.S.; Milstein, J.B.

    1984-01-01

    Significant improvements in the efficiencies of dendritic web and edge-supported-pulling silicon sheet solar cells have been obtained after hydrogen ion beam passivation for a period of ten minutes or less. We have studied the effects of the hydrogen ion beam treatment with respect to silicon material damage, silicon sputter rate, introduction of impurities, and changes in reflectance. The silicon sputter rate for constant ion beam flux of 0.60 +- 0.05 mA/cm 2 exhibits a maximum at approximately 1400-eV ion beam energy

  14. The Dual-Angle Method for Fast, Sensitive T1 Measurement in Vivo with Low-Angle Adiabatic Pulses

    Science.gov (United States)

    Bottomley, P. A.; Ouwerkerk, R.

    A new method for measuring T1 based on a measurement of the ratio, R, of the steady-state partially saturated NMR signals acquired at two fixed low flip angles (hip-angle and excitation-field ( B1) inhomogeneity result in roughly proportionate errors in the apparent T1. The method is best implemented with adiabatic low-angle pulses such as B1-independent rotation (BIR-4) or BIR-4 phase-cycled (BIRP) pulses, which permit measurements with surface coils. Experimental validation was obtained at 2 T by comparison of unlocalized inversion-recovery and dual-angle proton ( 1H) and phosphorus ( 31P) measurements from vials containing doped water with 0.04 ≤ T1 ≤ 2.8 s and from the metabolites in the calf muscles of eight human volunteers. Calf muscle values of 6 ± 0.5 s for phosphocreatine and around 3.7 ± 0.8 s for the adenosine triphosphates (ATP) were in good agreement with inversion-recovery T1 values and values from the literature. Use of the dual-angle method accelerated T1 measurement time by about fivefold over inversion recovery. The dual-angle method was implemented in a one-dimensional localized surface-coil 31P spectroscopy sequence, producing consistent T1 measurements from phantoms, the calf muscle, and the human liver. 31P T1 values of ATP in the livers of six volunteers were about 0.5 ± 0.1 to 0.6 ± 0.2 s: the total exam times were about 35 minutes per subject. The method is ideally suited to low-sensitivity and/or low-concentration moieties, such as in 31P NMR in vivo, where study-time limitations are critical, and for rapid 1H T1 imaging.

  15. Evaluation of size distribution of starch granules in selected wheat varieties by the Low Angle Laser Light Scattering method

    International Nuclear Information System (INIS)

    Capouchová, I.; Petr, J.; Marešová, D.

    2003-01-01

    The distribution of the size of wheat starch granules using the method LALLS (Low Angle Laser Light Scattering), followed by the evaluation of the effect of variety, experimental site and intensity of cultivation on the vol. % of the starch A (starch granules > 10 μm) was determined. The total starch content and crude protein content in dry matter of flour T530 in selected collection of five winter wheat varieties were determined. Vol. % of the starch A in evaluated collection of wheat varieties varied between 65.31 and 72.34%. The effect of a variety on the vol. % of starch A seemed to be more marked than the effect of site and intensity of cultivation. The highest vol. % of starch A reached evaluated varieties from the quality group C, i.e. varieties unsuitable for baking utilisation (except variety Contra with high total content of starch in dry matter of flour T530, but relatively low vol. % of starch A). A low vol. % of starch A was also found in the variety Hana (very good variety for baking utilisation). Certain variety differences followed from the evaluation of distribution of starch fractions of starch granules, forming starch A. In the case of varieties Hana, Contra and Siria higher representation of fractions up to 30 μm was recorded, while starch A in the varieties Estica and Versailles was formed in higher degree by size fractions of starch granules over 30 μm and particularly size fraction > 50 μm was greatest in these varieties of all evaluated samples. With increasing total starch content in dry matter of flour T530 the crude protein content decreased; the vol. % of starch A not always increased proportionally with increasing total starch content. (author)

  16. LSA Large Area Silicon Sheet Task Continuous Czochralski Process Development

    Science.gov (United States)

    Rea, S. N.

    1979-01-01

    A commercial Czochralski crystal growing furnace was converted to a continuous growth facility by installation of a small, in-situ premelter with attendant silicon storage and transport mechanisms. Using a vertical, cylindrical graphite heater containing a small fused quartz test tube linear from which the molten silicon flowed out the bottom, approximately 83 cm of nominal 5 cm diamter crystal was grown with continuous melt addition furnished by the test tube premelter. High perfection crystal was not obtained, however, due primarily to particulate contamination of the melt. A major contributor to the particulate problem was severe silicon oxide buildup on the premelter which would ultimately drop into the primary melt. Elimination of this oxide buildup will require extensive study and experimentation and the ultimate success of continuous Czochralski depends on a successful solution to this problem. Economically, the continuous Czochralski meets near-term cost goals for silicon sheet material.

  17. Method for more accurate transmittance measurements of low-angle scattering samples using an integrating sphere with an entry port beam diffuser

    International Nuclear Information System (INIS)

    Nilsson, Annica M.; Jonsson, Andreas; Jonsson, Jacob C.; Roos, Arne

    2011-01-01

    For most integrating sphere measurements, the difference in light distribution between a specular reference beam and a diffused sample beam can result in significant errors. The problem becomes especially pronounced in integrating spheres that include a port for reflectance or diffuse transmittance measurements. The port is included in many standard spectrophotometers to facilitate a multipurpose instrument, however, absorption around the port edge can result in a detected signal that is too low. The absorption effect is especially apparent for low-angle scattering samples, because a significant portion of the light is scattered directly onto that edge. In this paper, a method for more accurate transmittance measurements of low-angle light-scattering samples is presented. The method uses a standard integrating sphere spectrophotometer, and the problem with increased absorption around the port edge is addressed by introducing a diffuser between the sample and the integrating sphere during both reference and sample scan. This reduces the discrepancy between the two scans and spreads the scattered light over a greater portion of the sphere wall. The problem with multiple reflections between the sample and diffuser is successfully addressed using a correction factor. The method is tested for two patterned glass samples with low-angle scattering and in both cases the transmittance accuracy is significantly improved.

  18. Silicon Sheet Quality is Improved By Meniscus Control

    Science.gov (United States)

    Yates, D. A.; Hatch, A. E.; Goldsmith, J. M.

    1983-01-01

    Better quality silicon crystals for solar cells are possible with instrument that monitors position of meniscus as sheet of solid silicon is drawn from melt. Using information on meniscus height, instrument generates feedback signal to control melt temperature. Automatic control ensures more uniform silicon sheets.

  19. Congenital cheek teratoma with temporo-mandibular joint ankylosis managed with ultra-thin silicone sheet interpositional arthroplasty.

    Science.gov (United States)

    Bhatnagar, Ankur; Verma, Vinay Kumar; Purohit, Vishal

    2013-01-01

    Primary cheek teratomas are rare with joint ankylosis (TMJA). The fundamental aim in the treatment of TMJA is the successful surgical resection of ankylotic bone, prevention of recurrence, and aesthetic improvement by ensuring functional occlusion. Early treatment is necessary to promote proper growth and function of mandible and to facilitate the positive psychological development of child. Inter-positional arthroplasty with ultra-thin silicone sheet was performed. Advantages include short operative time, less foreign material in the joint space leading to negligible foreign body reactions and least chances of implant extrusion. Instead of excising a large bony segment, a thin silicone sheet was interposed and then sutured ensuring preservation of mandibular height. Aggressive post-operative physiotherapy with custom made dynamic jaw exerciser was used to prevent recurrence.

  20. Low cost monocrystalline silicon sheet fabrication for solar cells by advanced ingot technology

    Science.gov (United States)

    Fiegl, G. F.; Bonora, A. C.

    1980-01-01

    The continuous liquid feed (CLF) Czochralski furnace and the enhanced I.D. slicing technology for the low-cost production of monocrystalline silicon sheets for solar cells are discussed. The incorporation of the CLF system is shown to improve ingot production rate significantly. As demonstrated in actual runs, higher than average solidification rates (75 to 100 mm/hr for 150 mm 1-0-0 crystals) can be achieved, when the system approaches steady-state conditions. The design characteristics of the CLF furnace are detailed, noting that it is capable of precise control of dopant impurity incorporation in the axial direction of the crystal. The crystal add-on cost is computed to be $11.88/sq m, considering a projected 1986 25-slice per cm conversion factor with an 86% crystal growth yield.

  1. The Efficacy of a Silicone Sheet in Postoperative Scar Management.

    Science.gov (United States)

    Kim, Jin Sam; Hong, Joon Pio; Choi, Jong Woo; Seo, Dong Kyo; Lee, Eun Sook; Lee, Ho Seong

    2016-09-01

    Silicone gel sheeting has been introduced to prevent scarring, but objective evidence for its usefulness in scar healing is limited. Therefore, the authors' objective was to examine the effectiveness of silicone gel sheeting by randomly applying it to only unilateral scars from a bilateral hallux valgus surgery with symmetrical closure. In a prospective randomized, blinded, intraindividual comparison study, the silicone gel sheeting was applied to 1 foot of a hallux valgus incision scar (an experiment group) for 12 weeks upon removal of the stitches, whereas the symmetrical scar from the other foot was left untreated (a control group). The scars were evaluated at 4 and 12 weeks after the silicon sheet application. The Vancouver Scar Scale was used to measure the vascularity, pigmentation, pliability, height, and length of the scars. Adverse effects were also evaluated, and they included pain, itchiness, rash, erythema, and skin softening. At weeks 4 and 12, the experiment group scored significantly better on the Vancouver Scar Scale in all items, except length (P sheet does not cause adverse effects (P sheet application did show a significant improvement in prevention of postoperative scarring.

  2. Low angle X-ray scattering

    International Nuclear Information System (INIS)

    Torrianni, I.L.

    1983-01-01

    The theoretical and experimental problems appearing in diffraction experiments at very low angles by several kinds of materials are discussed. The importance of synchrotron radiation in such problems is shown. (L.C.) [pt

  3. LSSA large area silicon sheet task continuous Czochralski process development

    Science.gov (United States)

    Rea, S. N.

    1978-01-01

    A Czochralski crystal growing furnace was converted to a continuous growth facility by installation of a premelter to provide molten silicon flow into the primary crucible. The basic furnace is operational and several trial crystals were grown in the batch mode. Numerous premelter configurations were tested both in laboratory-scale equipment as well as in the actual furnace. The best arrangement tested to date is a vertical, cylindrical graphite heater containing small fused silicon test tube liner in which the incoming silicon is melted and flows into the primary crucible. Economic modeling of the continuous Czochralski process indicates that for 10 cm diameter crystal, 100 kg furnace runs of four or five crystals each are near-optimal. Costs tend to asymptote at the 100 kg level so little additional cost improvement occurs at larger runs. For these conditions, crystal cost in equivalent wafer area of around $20/sq m exclusive of polysilicon and slicing was obtained.

  4. Silicon Sheet Growth Development for the Large Area Sheet Task of the Low Cost Solar Array Project. Heat Exchanger Method - Ingot Casting Fixed Abrasive Method - Multi-Wire Slicing

    Science.gov (United States)

    Schmid, F.; Khattak, C. P.

    1978-01-01

    Solar cells fabricated from HEM cast silicon yielded up to 15% conversion efficiencies. This was achieved in spite of using unpurified graphite parts in the HEM furnace and without optimization of material or cell processing parameters. Molybdenum retainers prevented SiC formation and reduced carbon content by 50%. The oxygen content of vacuum cast HEM silicon is lower than typical Czochralski grown silicon. Impregnation of 45 micrometers diamonds into 7.5 micrometers copper sheath showed distortion of the copper layer. However, 12.5 micrometers and 15 micrometers copper sheath can be impregnated with 45 micrometers diamonds to a high concentration. Electroless nickel plating of wires impregnated only in the cutting edge showed nickel concentration around the diamonds. This has the possibility of reducing kerf. The high speed slicer fabricated can achieve higher speed and longer stroke with vibration isolation.

  5. Vacuum die casting of silicon sheet for photovoltaic applications. First quarterly report, March 16-June 30, 1979

    Energy Technology Data Exchange (ETDEWEB)

    None

    1979-01-01

    The obtective of this program is to develop a vacuum die-casting process for producing silicon sheet suitable for photovoltaic cells and to develop production techniques for optimization of polycrystallie silicon solar cell output. Efforts will examine process methods which are directed toward minimum cost processing of silicon into a quality suitable for producing solar cells with a terrestrial efficiency greater than 12% and having the potential to be scaled for large quantity production. In the vacuum die casting technique, silicon is melted under vacuum, and an evacuated die with a thin rectangular cavity is inserted into the melt. Liquid silicon is then injected into the die using a positive pressure of an inert gas. The major portion of the die casting work will be performed at Stanford Research Institute International under subcontract. The initial approach will follow parallel tracks: (1) obtain mechanical design parameters by using boron nitride, which has been shown to be non-wetting to silicon; (2) optimize silicon nitride material composition and coatings by sessile drop experiments; (3) test effectiveness of fluoride salt interfacial media with a graphite mold; and (4) test effect of surface finish using both boron nitride and graphite. Having established the material and mechanical boundary conditions, a finalized version of the prototype assembly will be constructed and the casting varibles determined. Polycrystalline silicon solar cells, with and without impurities, will be fabricated, characterized, and optimized at ARCCO Solar. The major activities will focus on the use of Wacker SILCO, HEM and in-house materials until vacuum die cast wafers are available. A baseline process with vacuum metallized contacts will be established and a reference mass production process with screen-printed metallization and high-throughput diffusions will also be obtained.

  6. Temporomandibular joint arthroplasty for osteoarthrosis: A series of 24 patients that received a uni- or bilateral inter-positional silicone sheet.

    Science.gov (United States)

    Boutault, F; Cavallier, Z; Lauwers, F; Prevost, A

    2018-06-01

    To evaluate mid-term results from using a silicone sheet for inter-positional arthroplasty in moderate or severe cases of osteoarthrosis of the temporo-mandibular joint (TMJ). To also determine any remaining indications from this method. This retrospective study included patients that underwent surgery between 2008 and 2016. Pre- and post-operative mouth opening (MO), according to inter-incisal distance (mm) and pain score (PS: 0=no pain to 4=very severe pain) were recorded for 24 patients. Patients were divided according to thickness of the silicone sheet (group A: 1.0 mm, group B: 1.5 mm). The cohort included 22 females (92%). Mean age at surgery was 55 years±13 (26-80). Mean length of follow-up was 26 months±24 (6-80). Mean improvement in MO was 8.2 mm (+33%) and of PS was 1.7 (-68%). MO was not improved for two patients and worsened for one. PS score improved for all patients. No statistical difference was found between groups A and B. There was also a tendency for degradation of outcomes over time. The poor reputation of prosthetic discoplasty was not as evident in our series, even though anatomical and functional status seemed to deteriorate over time. This is because total-joint prosthetic replacement is often proposed instead. However, for elderly or fragile patients that have severe pain, and regarding cost-benefit aspects, conventional arthroplasty can still be discussed, especially since French national health-care insurance does not yet support TMJ prosthetic replacement for osteoarthrosis. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

  7. Silicon Ingot Casting - Heat Exchanger Method (HEM). Multi-Wire Slicing - Fixed Abrasive Slicing Technique (Fast). Phase 4 Silicon Sheet Growth Development for the Large Area Sheet Task of the Low-Cost Solar Array Project

    Science.gov (United States)

    Schmid, F.

    1981-01-01

    The crystallinity of large HEM silicon ingots as a function of heat flow conditions is investigated. A balanced heat flow at the bottom of the ingot restricts spurious nucleation to the edge of the melted-back seed in contact with the crucible. Homogeneous resistivity distribution over all the ingot has been achieved. The positioning of diamonds electroplated on wirepacks used to slice silicon crystals is considered. The electroplating of diamonds on only the cutting edge is described and the improved slicing performance of these wires evaluated. An economic analysis of value added costs of HEM ingot casting and band saw sectioning indicates the projected add on cost of HEM is well below the 1986 allocation.

  8. Silicon Ingot Casting - Heat Exchanger Method Multi-wire Slicing - Fixed Abrasive Slicing Technique. Phase 3 Silicon Sheet Growth Development for the Large Area Sheet Task of the Low-cost Solar Array Project

    Science.gov (United States)

    Schmid, F.; Khattak, C. P.

    1979-01-01

    Several 20 cm diameter silicon ingots, up to 6.3 kg. were cast with good crystallinity. The graphite heat zone can be purified by heating it to high temperatures in vacuum. This is important in reducing costs and purification of large parts. Electroplated wires with 45 um synthetic diamonds and 30 um natural diamonds showed good cutting efficiency and lifetime. During slicing of a 10 cm x 10 cm workpiece, jerky motion occurred in the feed and rocking mechanisms. This problem is corrected and modifications were made to reduce the weight of the bladeheat by 50%.

  9. Crystal growth for high-efficiency silicon solar cells workshop: Summary

    Science.gov (United States)

    Dumas, K. A.

    1985-01-01

    The state of the art in the growth of silicon crystals for high-efficiency solar cells are reviewed, sheet requirements are defined, and furture areas of research are identified. Silicon sheet material characteristics that limit cell efficiencies and yields were described as well as the criteria for the ideal sheet-growth method. The device engineers wish list to the material engineer included: silicon sheet with long minority carrier lifetime that is uniform throughout the sheet, and which doesn't change during processing; and sheet material that stays flat throughout device processing, has uniform good mechanical strength, and is low cost. Impurities in silicon solar cells depreciate cell performance by reducing diffusion length and degrading junctions. The impurity behavior, degradation mechanisms, and variations in degradation threshold with diffusion length for silicon solar cells were described.

  10. Ultra-low-angle boundary networks within recrystallizing grains

    DEFF Research Database (Denmark)

    Ahl, Sonja Rosenlund; Simons, Hugh; Zhang, Yubin

    2017-01-01

    We present direct evidence of a network of well-defined ultra-low-angle boundaries in bulk recrystallizing grains of 99.5% pure aluminium (AA1050) by means of a new, three-dimensional X-ray mapping technique; dark-field X-ray microscopy. These boundaries separate lattice orientation differences o...

  11. The Interaction between Particles and Low Angle Boundaries during Recovering of Aluminium-Alumina Alloys

    DEFF Research Database (Denmark)

    Jones, A.R.; Hansen, Niels

    1981-01-01

    Certain quantitative and qualitative aspects both of subgrain growth and of the interaction between particles and low angle grain boundaries during recovery have been investigated in two aluminium alloys containing low volume fractions of small alumina particles. Quantitative data have been...... pinning. The discrepancies between the experimental and theoretical results can be rationalised in terms of the limited nature of the physical effects modelled in the Zener analysis....

  12. Seismic Slip on an Oblique Detachment Fault at Low Angles

    Science.gov (United States)

    Janecke, S. U.; Steely, A. N.; Evans, J. P.

    2008-12-01

    Pseudotachylytes are one of the few accepted indicators of seismic slip along ancient faults. Low-angle normal faults have produced few large earthquakes in historic times and low-angle normal faults (detachment faults) are typically severely misoriented relative to a vertical maximum compressive stress. As a result many geoscientists question whether low-angle normal faults produce earthquakes at low angles. Relationships in southern California show that a major low-angle normal-oblique fault slipped at low angles and produced large earthquakes. The exhumed Late Cenozoic West Salton detachment fault preserves spectacular fault- related pseudotachylytes along its fault plane and injected into its hanging wall and footwall. Composite pseudotachylyte zones are up to 1.25 m thick and persists over lateral distances of at least 10's of meters. Pseudotachylyte is common in most thin sections of damaged fault rocks with more than 20% (by volume) of cataclasite. We recognized the presence of original melt using numerous criteria: abundant spherulites in thin sections, injection structures at both the thin-section and outcrop scale, black aphanitic textures, quenched vein margins, variations in microcrystallite textures and/or size with respect to the vein margin, and glassy textures in hand sample. Multiple earthquakes are inferred to produce the layered "stratigraphy" in some exposures of pseudotachylytes. We infer that the West Salton detachment fault formed and slipped at low angles because it nearly perfectly reactivates a Cretaceous ductile thrust system at the half km scale and dips between 10 and 45 degrees. The about 30 degree NNE dip of the detachment fault on the north side of Yaqui Ridge is likely steeper than its dip during detachment slip because there is local steepening on the flanks of the Yaqui Ridge antiform in a contractional stepover of a crosscutting Quaternary San Felipe dextral fault zone. These relationships indicate a low dip on the detachment

  13. Low-angle X-ray scattering from spices

    International Nuclear Information System (INIS)

    Desouky, O.S.; Ashour, Ahmed H.; Abdullah, Mohamed I.; Elshemey, Wael M.

    2002-01-01

    Low-angle scattering of X-rays is characterized by the presence of one or more peaks in the forward direction of scattering. These peaks are due to the interference of photons coherently scattered from the molecules of the medium. Thus these patterns are closely linked to the molecular structure of the investigated medium. In this work, low-angle X-ray scattering (LAXS) profiles of five spices; pimpinella anisum (anise), coriandrum sativum (coriander), cuminum cyminum (cumin), foenculum vulgare (fennel) and nigella sativa (nigella or black cumin) are presented after extensive measurements. It is found that all spices exhibit one characteristic peak at a scattering angle around 10 deg. This is equivalent to a value x=0.0565 A -1 , where x=sin(θ/2)/λ. The full width at half maximum (FWHM) of this peak is found to be characteristic for each type of the investigated spices. The possibility to detect the irradiation of these spices from their LAXS profiles is also examined after 10, 20, 30 and 40 kGy doses of gamma radiation. Except for anise, coriander and cumin at 40 kGy, there are no detectable deviations from the control samples in the scattering profiles of irradiated samples. These results comply with the recommendations of the FDA (US Food and Drug Administration) which defines 30 kGy as the maximum dose for irradiation of spices. The present technique could be used to detect over-irradiation, which causes damage to the molecular structure of some spices

  14. Minority carrier diffusion lengths and absorption coefficients in silicon sheet material

    Science.gov (United States)

    Dumas, K. A.; Swimm, R. T.

    1980-01-01

    Most of the methods which have been developed for the measurement of the minority carrier diffusion length of silicon wafers require that the material have either a Schottky or an ohmic contact. The surface photovoltage (SPV) technique is an exception. The SPV technique could, therefore, become a valuable diagnostic tool in connection with current efforts to develop low-cost processes for the production of solar cells. The technique depends on a knowledge of the optical absorption coefficient. The considered investigation is concerned with a reevaluation of the absorption coefficient as a function of silicon processing. A comparison of absorption coefficient values showed these values to be relatively consistent from sample to sample, and independent of the sample growth method.

  15. Low angle X-ray scattering in biological tissues

    International Nuclear Information System (INIS)

    Lemos, Carla; Braz, Delson; Pinto, Nivia G.V.; Lima, Joao C.; Castro, Carlos R.F.; Filgueiras, R.A.; Mendonca, Leonardo; Lopes, Ricardo T.; Barroso, Regina C.

    2007-01-01

    Low-angle x-ray scatter (LAXS) for tissue characterization is based on the differences which result from the interference of photons coherently scattered from molecules of each sample. Biological samples (bone, blood and blood components) have been studied in recent years in our laboratory using powder diffractometer. The scattering information was obtained using a Shimadzu DRX 6000 diffractometer at the Nuclear Instrumentation Laboratory, Rio de Janeiro, Brazil. Unpolarized monoenergetic Kα radiation from Cu provided 8.04 keV photons. The measurements were made in reflection mode (θ-2θ geometry), with the sample stationary on a goniometer which rotates the sample and detector about an axis lying in the plane of the top of the sample holder. LAXS profiles from whole blood, plasma and formed elements were measured to investigate the nature of scattering from such lyophilized samples. The statistical analysis shows that the variation found for the characterization parameters is significant for whole blood considering the age. Gender was positively associated with the variation of the second peak position for the profiles obtained for formed elements. The correlation of the measured relative coherent intensity with the mineral content in the bone samples was investigated. These results suggest that the measurement of bone mineral content within trabecular bone can be performed by using quantitative coherent scattering information. (author)

  16. Polarization Smoothing Generalized MUSIC Algorithm with Polarization Sensitive Array for Low Angle Estimation.

    Science.gov (United States)

    Tan, Jun; Nie, Zaiping

    2018-05-12

    Direction of Arrival (DOA) estimation of low-altitude targets is difficult due to the multipath coherent interference from the ground reflection image of the targets, especially for very high frequency (VHF) radars, which have antennae that are severely restricted in terms of aperture and height. The polarization smoothing generalized multiple signal classification (MUSIC) algorithm, which combines polarization smoothing and generalized MUSIC algorithm for polarization sensitive arrays (PSAs), was proposed to solve this problem in this paper. Firstly, the polarization smoothing pre-processing was exploited to eliminate the coherence between the direct and the specular signals. Secondly, we constructed the generalized MUSIC algorithm for low angle estimation. Finally, based on the geometry information of the symmetry multipath model, the proposed algorithm was introduced to convert the two-dimensional searching into one-dimensional searching, thus reducing the computational burden. Numerical results were provided to verify the effectiveness of the proposed method, showing that the proposed algorithm has significantly improved angle estimation performance in the low-angle area compared with the available methods, especially when the grazing angle is near zero.

  17. Utility of Vaccum Pressed Silicon Sheet as a Bite Raising Appliance in the Management of TMJ Dysfunction Syndrome.

    Science.gov (United States)

    Datarkar, Abhay; Daware, Surendra; Dande, Ravi

    2017-09-01

    Temporomandibular disorders (TMDs) represent a group of painful conditions involving the muscles of mastication and the temporomandibular joint (TMJ) that frequently encountered in general clinical practice. This study is designed to assess the utility of vacuum pressed silicon sheet as a bite raising appliance in the management of TMJ dysfunction syndrome. The patients for this study were selected from those with the chief complaint of TMJ disorder. Out of 200 patients, 104 patients were diagnosed with subluxation and 96 patients were diagnosed with internal derangement of temporomandibular joint. All the reported cases were managed conservatively with physiotherapy and muscle relaxant therapy for one week period and followed with silicon bite raising appliance over both the arches in the subsequent period. All the patients had pain relief within six months duration as graded over verbal analog scale. ANOVA scale was used for comparision of VAS scores. The use of vacuum pressed bite raising appliance in the management of TMJ disorder was found to be satisfactorily effective in alleviation of pain symptom in our study group.

  18. Large area silicon sheet by EFG. Fourth quarterly report, October 1-December 31, 1978

    Energy Technology Data Exchange (ETDEWEB)

    Wald, F.V.

    1979-03-01

    Crystal growth station no. 1 further explored displaced die concepts, along with some initial work on buckle characterization. Also, convective impurity redistribution was further studied. In particular, a side channel die was used to grow material doped with aluminum and compare the results at least semiquantitatively with computer calculations. The ribbons grown have not been characterized yet. In station no. 3A growth from single cartridges was continued to create a quality baseline to allow comparison of the results with those in the upcoming multiple run and to choose the most appropriate die design. Also fabrication and assembly work on the actual five ribbon furnace continued. On furnace 17 progress was made toward the development of the video optical system for edge position and meniscus height control. Also, in preparation for a detailed program, designed to explore the buckling problem, ribbon width ribon was then grown under stable conditions without a cold shoe, an achievement essential to finally arrive at quantitative correlations between growth conditions and buckle formation. The most significant result from the characterization program was a demonstration that the original runs with displaced dies were indeed reproducible, inasmuch as large area cells (7.5 x 7.5 cm/sup 2/) of approx. 9% efficiency could be fabricated again from run 18-103, a repeat of run no. 18-102 which had previously produced the best cells.

  19. Low cost silicon solar array project large area silicon sheet task: Silicon web process development

    Science.gov (United States)

    Duncan, C. S.; Seidensticker, R. G.; Mchugh, J. P.; Blais, P. D.; Davis, J. R., Jr.

    1977-01-01

    Growth configurations were developed which produced crystals having low residual stress levels. The properties of a 106 mm diameter round crucible were evaluated and it was found that this design had greatly enhanced temperature fluctuations arising from convection in the melt. Thermal modeling efforts were directed to developing finite element models of the 106 mm round crucible and an elongated susceptor/crucible configuration. Also, the thermal model for the heat loss modes from the dendritic web was examined for guidance in reducing the thermal stress in the web. An economic analysis was prepared to evaluate the silicon web process in relation to price goals.

  20. The Trapping of Helium at a Low Angle Tilt Boundary in Molybdenum

    NARCIS (Netherlands)

    Evans, J.H.; Veen, A. van; Hosson, J.Th.M. De; Bullough, R.; Willis, J.R.

    1984-01-01

    This paper presents experimental evidence of helium trapping at a set of b = [100] edge dislocations defining a low angle tilt boundary in molybdenum together with theoretical results on two aspects of helium-dislocation behaviour. The low angle boundary, with a misfit angle of ≈1/5 °, was found

  1. Factors influencing fast low angle positive contrast steady-state free precession (FLAPS) magnetic resonance imaging

    International Nuclear Information System (INIS)

    Dharmakumar, Rohan; Koktzoglou, Ioannis; Li Debiao

    2007-01-01

    The presence of susceptibility-shifting media can lead to signal voids in magnetic resonance images. While signal voids have been traditionally used to detect such magnetic perturbers, selective magnetic resonance imaging of off-resonant spins surrounding susceptibility-shifted media allows for them to be visualized as hyper-intense (positive contrast) regions. These positive contrast methods can potentially improve the detection conspicuity of magnetic perturbers against regions that appear dark due to the absence of protons, such as air. Recently, a fast low angle positive contrast steady-state free precession (FLAPS) technique has been proposed as a positive contrast imaging method. This work systematically evaluates the contrast characteristics and acquisition strategies of FLAPS-based imaging from the standpoint of imaging parameters and physical properties of the magnetic perturbers. Results show that scan parameters (T R , flip angle, B 0 ), physical properties of the perturber (size and concentration of shift reagent) and the ratio of the relaxation constants (T 1 /T 2 ) of the medium are significant factors influencing the FLAPS-based positive contrast

  2. Cyclically induced softening due to low-angle boundary annihilation in a martensitic steel

    International Nuclear Information System (INIS)

    Sauzay, Maxime; Brillet, Helene; Monnet, Isabelle; Mottot, Michel; Barcelo, Francoise; Fournier, Benjamin; Pineau, Andre

    2005-01-01

    Martensitic steels are known for their softening during cyclic tests carried out at high temperature. The softening has been at least partially explained by lath and sub-grain boundary elimination. This article is dedicated to an attempt at modelling both phenomena. Thanks to mechanical tests it is shown that the softening is mainly due to a decrease of the backstress. Transmission electron microscopy allows us to propose a mechanism of low-angle boundary elimination. Annihilation between dislocations of low-angle boundaries and incident mobile dislocations is modelled. The macroscopic backstress is finally computed using a Hall-Petch law and the Taylor model

  3. Accurate electron channeling contrast analysis of a low angle sub-grain boundary

    International Nuclear Information System (INIS)

    Mansour, H.; Crimp, M.A.; Gey, N.; Maloufi, N.

    2015-01-01

    High resolution selected area channeling pattern (HR-SACP) assisted accurate electron channeling contrast imaging (A-ECCI) was used to unambiguously characterize the structure of a low angle grain boundary in an interstitial-free-steel. The boundary dislocations were characterized using TEM-style contrast analysis. The boundary was determined to be tilt in nature with a misorientation angle of 0.13° consistent with the HR-SACP measurements. The results were verified using high accuracy electron backscatter diffraction (EBSD), confirming the approach as a discriminating tool for assessing low angle boundaries

  4. Designing a compensating quartz fiber calorimeter for low angle calorimetry at LHC

    International Nuclear Information System (INIS)

    Ferrando, A.; Fouz, M.C.; Josa, M.I.; Khan, A.; Rosowsky, A.; Salicio, J.M.

    1996-01-01

    We present a design of a compensating quartz fiber calorimeter, made of a unique active section, and ment for the specific physics requirements of the low angle calorimetry in LHC experiments. The purposed calorimeter is exemplified for the case of the CMS experiment

  5. An Accounting Method for Economic Growth

    OpenAIRE

    Hongchun Zhao

    2012-01-01

    As Chari et al. (2007) indicate, many growth theories explaining frictions in real economies are equivalent to a competitive economy, with some exogenous taxes. Using this idea, I developed an accounting method for identifying fundamental causes of economic growth. A two-sector neoclassical growth model with taxes is used as a prototype economy, and its equilibrium conditions define wedges. These wedges endogenously determine the long run growth rate, which is exogenous and not correlated wit...

  6. Architecture of a low-angle normal fault zone, southern Basin and Range (SE California)

    Science.gov (United States)

    Goyette, J. A.; John, B. E.; Campbell-Stone, E.; Stunitz, H.; Heilbronner, R.; Pec, M.

    2009-12-01

    Exposures of the denuded Cenozoic detachment fault system in the southern Sacramento Mountains (SE California) delimit the architecture of a regional low-angle normal fault, and highlight the evolution of these enigmatic faults. The fault was initiated ~23 Ma in quartzo-feldspathic basement gneiss and granitoids at a low-angle (2km, and amplitudes up to 100m. These corrugations are continuous along their hinges for up to 3.6 km. Damage zone fracture intensity varies both laterally, and perpendicular to the fault plane (over an area of 25km2), decreasing with depth in the footwall, and varies as a function of lithology and proximity to corrugation walls. Deformation is concentrated into narrow damage zones (100m) are found in areas where low-fracture intensity horses are corralled by sub-horizontal zones of cataclasite (up to 8m) and thick zones of epidote (up to 20cm) and silica-rich alteration (up to 1m). Sub-vertical shear and extension fractures, and sub-horizontal shear fractures/zones dominate the NE side of the core complex. In all cases, sub-vertical fractures verge into or are truncated by low-angle fractures that dominate the top of the damage zone. These low-angle fractures have an antithetic dip to the detachment fault plane. Some sub-vertical fractures become curviplanar close to the fault, where they are folded into parallelism with the sub-horizontal fault surface in the direction of transport. These field data, corroborated by ongoing microstructural analyses, indicate fault activity at a low angle accommodated by a variety of deformation mechanisms dependent on lithology, timing, fluid flow, and fault morphology.

  7. The formation of low-angle eolian stratification through the migration of protodunes

    Science.gov (United States)

    Ewing, R. C.; Phillips, J. D.; Weymer, B. A.; Barrineaux, P.; Bowling, R.; Nittrouer, J. A.

    2017-12-01

    Protodunes are low-relief, slipfaceless migrating bed forms that represent the emergent form of eolian sand dunes. Protodunes develop as cm-scale topography out of a flat bed of sand and evolve spatially and temporally into dunes with angle-of-repose slipfaces. Protodunes at White Sands Dune Field in New Mexico form at the upwind, trailing margin of the field, on dune stoss slopes, and in interdune areas. Here we analyze protodunes at the upwind margin of White Sands by coupling 200 mHz ground penetrating radar (GPR) with time-series high-resolution topography to characterize the origin and evolution of protodune stratification and the stratigraphic transition into fully developed dunes. We surveyed a 780m transect in the resultant transport direction of the dune field from SW to NE from sand patches through protodunes and into the first dune. We used airborne lidar surveys and structure-from-motion photogrammetry from 2007, 2008, 2009, 2010, 2015, and 2016. We find that protodune stratification forms at angles between 0-10 degrees by protodune migration. Dip angles increase as protodune amplitude increases along the transect. Accumulation of low-angle stratification increases across the first 650m and ranges from none to subcritical. Nearly aggradational accumulation of low-angle stratification occurs over the last 100m and is a precursor to angle-of-repose slipface formation. The origins of the aggradation and slipface development appear to be linked to protodune merging, dune interactions, and possibly to the development of a dune field-scale boundary layer. Protodunes and the formation of low-angle stratification at the upwind margin of White Sands are a good analog to the initiation of dune field development from sand sheets and the formation of low-angle stratification found at the base of eolian successions in the stratigraphic record.

  8. Advances on detectors for low-angle scattering of epithermal neutrons

    International Nuclear Information System (INIS)

    Perelli Cippo, E; Gorini, G; Tardocchi, M; Andreani, C; Pietropaolo, A; Senesi, R; Rhodes, N J; Schoonveld, E M

    2008-01-01

    The Very Low Angle Detector (VLAD) installed at the ISIS spallation neutron source is a novel instrument for epithermal neutron scattering with a range of applications in solid state physics. VLAD extends the kinematical space of the VESUVIO spectrometer to low momentum transfers at neutron energies above 1 eV. Measurements at scattering angles as low as 1° have been made with limitations due to the achievable signal/background ratio. (technical design note)

  9. Ultrathin Silicon Sheet in the Management of Unilateral Post-traumatic Temporo-Mandibuar Joint Ankylosis in Children: A Good Alternative to Conventional Techniques.

    Science.gov (United States)

    Aggarwal, Sushil Kumar; Ankur, Bhatnagar; Jain, R K

    2015-09-01

    We have described a new technique of using ultra-thin silicon sheet (0.2 mm) between two transected bony ends for temporo-mandibular joint (TMJ) ankylosis in children with advantages of short operative time, minimal foreign material insertion and faster recovery time post-operatively which makes our technique a good alternative to conventional techniques. Our study is a non-randomized prospective study conducted on 10 children aged between 4 and 15 years who presented to our tertiary care institute with severe trismus after traumatic injury and were willing to undergo this new technique. The main outcome measure taken into consideration was difference between pre-operative, intra-operative (on table) and post-operative mouth opening (minimum 2 years follow-up). The pre-operative mouth opening in our cases varied from 1 to 5 mm. The intra-operative mouth opening achieved ranged from 2.8 to 3.2 cm. The mouth opening was about more than 2.7 cm in all our cases at 2 years of follow-up. Our technique is a good alternative to conventional techniques used for TMJ ankylosis in children but few more randomized controlled trials are required to assess its effectiveness in comparison to conventional techniques and for universal adoption of this technique.

  10. Low-angle dunes in the Changjiang (Yangtze) Estuary: Flow and sediment dynamics under tidal influence

    Science.gov (United States)

    Hu, Hao; Wei, Taoyuan; Yang, Zhongyong; Hackney, Christopher R.; Parsons, Daniel R.

    2018-05-01

    It has long been highlighted that important feedbacks exist between river bed morphology, sediment transport and the turbulent flow field and that these feedbacks change in response to forcing mechanisms. However, our current understanding of bedform dynamics is largely based on studies of steady flow environments and cohesionless bed conditions. Few investigations have been made under rapidly changing flows. Here, we examine flow and sediment dynamics over low-angle dunes in unsteady flows in the Changjiang (Yangtze) Estuary, China. Topography, flow and sediment data were collected over a reach ca 1.8 km long through a semi-diurnal tidal cycle in a moderate tide of flood season. The results show that: (1) roughness length derived from the upper flow changes little with the flow reversing and displays the same value on both the ebb and flood tide. Moreover, the variability of individual bedform features plays an important role in roughness length variation. (2) Shear stress over the crest of low-angle dunes roughly represents the total spatially averaged stress over dunes in this study area, which has significant implications for advancing numerical models. (3) Changes in morphology, flow and sediment dynamics over dunes through time reveal how low-angle dunes evolve within a tidal cycle. (4) The clockwise hysteresis loops between flow dynamics and bedform features (height and aspect ratio) are also observed. The combination of suspended sediment transport and bedload transport on dune transformation and migration attributes to the clockwise hysteresis. The specific sediment composition of the riverbed, in some extent, affects the mechanism of sediment transport related to the exchange between suspended sediment and riverbed, but further investigation is needed to figure out the mechanism behind this for extended series of tides, such as spring/neap tide and tides in flooding and dry season.

  11. The very low angle detector for high-energy inelastic neutron scattering on the VESUVIO spectrometer

    International Nuclear Information System (INIS)

    Perelli Cippo, E.; Gorini, G.; Tardocchi, M.; Pietropaolo, A.; Andreani, C.; Senesi, R.; Rhodes, N.J.; Schooneveld, E.M.

    2008-01-01

    The Very Low Angle Detector (VLAD) bank has been installed on the VESUVIO spectrometer at the ISIS spallation neutron source. The new device allows for high-energy inelastic neutron scattering measurements, at energies above 1 eV, maintaining the wave vector transfer lower than 10A -1 . This opens a still unexplored region of the kinematical (q,ω) space, enabling new and challenging experimental investigations in condensed matter. This paper describes the main instrumental features of the VLAD device, including instrument design, detector response, and calibration procedure

  12. The very low angle detector for high-energy inelastic neutron scattering on the VESUVIO spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Perelli Cippo, E.; Gorini, G.; Tardocchi, M. [Dipartimento di Fisica ' G. Occhialini' , Universita degli Studi di Milano-Bicocca, Piazza della Scienza 3, 20126 Milano (Italy); Pietropaolo, A. [Dipartimento di Fisica ' G. Occhialini' , CNISM-Universita degli Studi di Milano-Bicocca, Piazza della Scienza 3, 20126 Milano (Italy); NAST Center - Nanoscienze-Nanotecnologie-Strumentazione, Universita degli Studi di Roma Tor Vergata, via della Ricerca Scientifica 1, 00133 Roma (Italy)], E-mail: antonino.pietropaolo@mib.infn.it; Andreani, C.; Senesi, R. [Dipartimento di Fisica and Centro NAST - Nanoscienze-Nanotecnologie-Strumentazione, Universita degli Studi di Roma Tor Vergata, via della Ricerca Scientifica 1, 00133 Roma (Italy); Rhodes, N.J.; Schooneveld, E.M. [ISIS Facility, Rutherford Appleton Laboratory, Chilton, Didcot, Oxfordshire 0QX OX11 (United Kingdom)

    2008-05-01

    The Very Low Angle Detector (VLAD) bank has been installed on the VESUVIO spectrometer at the ISIS spallation neutron source. The new device allows for high-energy inelastic neutron scattering measurements, at energies above 1 eV, maintaining the wave vector transfer lower than 10A{sup -1}. This opens a still unexplored region of the kinematical (q,{omega}) space, enabling new and challenging experimental investigations in condensed matter. This paper describes the main instrumental features of the VLAD device, including instrument design, detector response, and calibration procedure.

  13. The very low angle detector for high-energy inelastic neutron scattering on the VESUVIO spectrometer

    Science.gov (United States)

    Perelli Cippo, E.; Gorini, G.; Tardocchi, M.; Pietropaolo, A.; Andreani, C.; Senesi, R.; Rhodes, N. J.; Schooneveld, E. M.

    2008-05-01

    The Very Low Angle Detector (VLAD) bank has been installed on the VESUVIO spectrometer at the ISIS spallation neutron source. The new device allows for high-energy inelastic neutron scattering measurements, at energies above 1 eV, maintaining the wave vector transfer lower than 10Å-1. This opens a still unexplored region of the kinematical (q, ω) space, enabling new and challenging experimental investigations in condensed matter. This paper describes the main instrumental features of the VLAD device, including instrument design, detector response, and calibration procedure.

  14. THE GROWTH POINTS OF STATISTICAL METHODS

    OpenAIRE

    Orlov A. I.

    2014-01-01

    On the basis of a new paradigm of applied mathematical statistics, data analysis and economic-mathematical methods are identified; we have also discussed five topical areas in which modern applied statistics is developing as well as the other statistical methods, i.e. five "growth points" – nonparametric statistics, robustness, computer-statistical methods, statistics of interval data, statistics of non-numeric data

  15. Growth of large size lithium niobate single crystals of high quality by tilting-mirror-type floating zone method

    Energy Technology Data Exchange (ETDEWEB)

    Sarker, Abdur Razzaque, E-mail: razzaque_ru2000@yahoo.com [Department of Physics, University of Rajshahi (Bangladesh)

    2016-05-15

    Large size high quality LiNbO{sub 3} single crystals were grown successfully by tilting-mirror-type floating zone (TMFZ) technique. The grown crystals were characterized by X-ray diffraction, etch pits density measurement, Impedance analysis, Vibrating sample magnetometry (VSM) and UV-Visible spectrometry. The effect of mirror tilting during growth on the structural, electrical, optical properties and defect density of the LiNbO{sub 3} crystals were investigated. It was found that the defect density in the crystals reduced for tilting the mirror in the TMFZ method. The chemical analysis revealed that the grown crystals were of high quality with uniform composition. The single crystals grown by TMFZ method contains no low-angle grain boundaries, indicating that they can be used for high efficiency optoelectronic devices. (author)

  16. Low-angle polarized neutron and X-ray scattering from magnetic nanolayers and nanostructures

    CERN Document Server

    Paul, Amitesh

    2017-01-01

    This research monograph presents the latest results related to the characterization of low dimensional systems. Low-angle polarized neutron scattering and X-ray scattering at grazing incidence are used as the two main techniques to explore various physical phenomena of these systems. Special focus is put on systems like thin film transition metal and rare-earth layers, oxide heterostructures, hybrid systems, self-assembled nanostructures and self-diffusion.  Readers will gain in-depth knowledge about the usage of specular scattering and off-specular scattering techniques. Investigation of in-plane and out-of-plane structures and magnetism with vector magnetometric information is illustrated comprehensively. The book caters to a wide audience working in the field of nano-dimensional magnetic systems and the neutron and X-ray reflectometry community in particular.

  17. Low-angle X-ray scattering properties of irradiated spices

    International Nuclear Information System (INIS)

    Almeida, A.P.G.; Braz, D.; Barroso, R.C.; Lopes, R.T.

    2007-01-01

    The scattering of X-rays at low angles (LAXS) is a technique dominated by the coherent scattering process. One characteristic observation of low-angle coherent scattering is the so-called molecular interference effect, being characterized by the presence of one or more peaks in the forward direction of scattering. In the present study, LAXS profiles from five different spices are carefully measured in order to establish characteristic scattering signatures. Samples of Ceylon cinnamon, cumin, nutmeg, paprika and black pepper were bought in local market in Rio de Janeiro, Brazil. The LAXS patterns were obtained using a Shimadzu DRX 6000 diffractometer in reflection geometry. Coherent scattering patterns are measured for the samples for θ=5-35 o . The data were collected in 0.05 o increments every 3 s. In order to evaluate the possible molecular structure changes caused to the irradiation procedure, the signatures obtained for control (non-irradiated) spices were compared with spice samples irradiated with different doses varying from 3 to 40 kGy. The LAXS patterns of all samples were obtained after 30, 60, 90, 120 days to evaluate the effect of storage period. Scattering profiles from spices irradiated with different irradiation doses were obtained and the results compared. For each spice, there is no considerable deviation in shape in function of the irradiation dose. It indicates that the molecular structure of each analyzed spices is preserved considering the dose range chosen. The results show that the molecular structure was found to be stable during storage at the ambient temperature for up to 4 months

  18. Method for solid state crystal growth

    Science.gov (United States)

    Nolas, George S.; Beekman, Matthew K.

    2013-04-09

    A novel method for high quality crystal growth of intermetallic clathrates is presented. The synthesis of high quality pure phase crystals has been complicated by the simultaneous formation of both clathrate type-I and clathrate type-II structures. It was found that selective, phase pure, single-crystal growth of type-I and type-II clathrates can be achieved by maintaining sufficient partial pressure of a chemical constituent during slow, controlled deprivation of the chemical constituent from the primary reactant. The chemical constituent is slowly removed from the primary reactant by the reaction of the chemical constituent vapor with a secondary reactant, spatially separated from the primary reactant, in a closed volume under uniaxial pressure and heat to form the single phase pure crystals.

  19. Gap States at Low-Angle Grain Boundaries in Monolayer Tungsten Diselenide

    KAUST Repository

    Huang, Yu Li; Ding, Zijing; Zhang, Wenjing; Chang, Yung-Huang; Shi, Yumeng; Li, Lain-Jong; Song, Zhibo; Zheng, Yu Jie; Chi, Dongzhi; Quek, Su Ying; Wee, Andrew T. S.

    2016-01-01

    Two-dimensional (2D) transition metal dichalcogenides (TMDs) have revealed many novel properties of interest to future device applications. In particular, the presence of grain boundaries (GBs) can significantly influence the material properties of 2D TMDs. However, direct characterization of the electronic properties of the GB defects at the atomic scale remains extremely challenging. In this study, we employ scanning tunneling microscopy and spectroscopy to investigate the atomic and electronic structure of low-angle GBs of monolayer tungsten diselenide (WSe2) with misorientation angles of 3-6°. Butterfly features are observed along the GBs, with the periodicity depending on the misorientation angle. Density functional theory calculations show that these butterfly features correspond to gap states that arise in tetragonal dislocation cores and extend to distorted six-membered rings around the dislocation core. Understanding the nature of GB defects and their influence on transport and other device properties highlights the importance of defect engineering in future 2D device fabrication. © 2016 American Chemical Society.

  20. Ultra-fast low-angle rapid acquisition and relaxation enhancement (UFLARE) in patients with epilepsy

    International Nuclear Information System (INIS)

    Eriksson, S.H.; Symms, M.R.; Woermann, F.G.; Kendall, B.; Stevens, J.M.; Stepney, A.; Barker, G.J.; Niendorf, T.

    2001-01-01

    MRI is an important diagnostic tool in patients with epilepsy, but patient motion during long scans may result in image artefacts. We studied the utility of an ultra-fast MR sequence in patients with epilepsy. Ultra-fast low-angle rapid acquisition and relaxation enhancement (UFLARE) images were acquired for 100 consecutive patients and nine control subjects. Scans were compared with routine T2-weighted spin echo images for signal-to-noise ratio, contrast, and conspicuity, followed by a blind review of lesion detectability. UFLARE scans were also acquired for 15 patients who moved during conventional scans. All UFLARE scans had lower signal-to-noise ratios and lower contrast than the T2-weighted images. Compared with T1- and T2-weighted, PD and FLAIR images, 86% of hippocampal sclerosis (HS), 92% of large but only 24% of small white-matter lesions were detected on the blind review of the UFLARE images. Reduced motion artefacts were seen on the UFLARE images in all 15 patients who moved during the conventional scans, and in three patients UFLARE was the only sequence we were able to obtain. Despite the lower lesion detectability for smaller lesions, the use of an ultra-fast MRI sequence such as UFLARE may be very useful in patients who are not able to co-operate during conventional MRI examinations, if a general anaesthetic is to be avoided. (orig.)

  1. Gap States at Low-Angle Grain Boundaries in Monolayer Tungsten Diselenide

    KAUST Repository

    Huang, Yu Li

    2016-05-03

    Two-dimensional (2D) transition metal dichalcogenides (TMDs) have revealed many novel properties of interest to future device applications. In particular, the presence of grain boundaries (GBs) can significantly influence the material properties of 2D TMDs. However, direct characterization of the electronic properties of the GB defects at the atomic scale remains extremely challenging. In this study, we employ scanning tunneling microscopy and spectroscopy to investigate the atomic and electronic structure of low-angle GBs of monolayer tungsten diselenide (WSe2) with misorientation angles of 3-6°. Butterfly features are observed along the GBs, with the periodicity depending on the misorientation angle. Density functional theory calculations show that these butterfly features correspond to gap states that arise in tetragonal dislocation cores and extend to distorted six-membered rings around the dislocation core. Understanding the nature of GB defects and their influence on transport and other device properties highlights the importance of defect engineering in future 2D device fabrication. © 2016 American Chemical Society.

  2. Study of human blood and hemocomponents irradiated by low angle x ray scattering (LAXS)

    Energy Technology Data Exchange (ETDEWEB)

    Pinto, Nivia G. Villela; Barroso, Regina C. [Universidade do Estado do Rio de Janeiro (UERJ), RJ (Brazil). Inst. de Fisica. Dept. de Fisica Aplicada e Termodinamica], e-mail: nitatag@gmail.com; Mota, Carla L.S.; Almeida, Andre P.; Azeredo, Soraia R.; Braz, Delson [Coordenacao dos Programas de Pos-graduacao em Engenharia (COPPE/UFRJ), RJ (Brazil). Lab. de Instrumentacao Nuclear], e-mail: delson@lin.ufrj.br

    2009-07-01

    Irradiation of blood and blood components is currently practiced in developed and in a few developing countries. The main purpose of this process is the prevention of graft versus host disease in immunodeficient patients. The Food and Drug Administration recommends a dose range of 15 Gy to 25 Gy for these blood components. When x-ray photons are scattered from biological samples, their angular distribution shows one or more peaks in the forward direction of scattering. These peaks are characteristic for the investigated samples. Due to its wide range of biological and medical applications, low-angle x-ray scattering has attracted the attention of many authors. Thus in this present work was studied the possible variations in scattering profiles due to the irradiation when the gender of patients was considered. Fresh blood specimens were obtained from volunteers using vacutainer tubes containing EDTA, at the Dr. Eliel Figueiredo Laboratory, Rio de Janeiro. All the samples were lyophilized for 48 hours in a freeze drier in order to remove the water. The scattering measurements were carried out in e-2e reflection geometry using a powder diffractometer Shimadzu XRD- 6000. The measured characterization parameters for LAXS were associated with epidemiological data (gender). The mean values of the different parameters were compared using the Students's t-test for each characterization parameters. The scattering profiles from plasma and formed elements are characterized by the presence of two peaks in the forward direction of scattering. For epidemiological data (gender) analyzed was not found significant changes in the mostly of characterization parameters (p>0.05). (author)

  3. Development of new instrumentation for epithermal neutron scattering at very low angles

    International Nuclear Information System (INIS)

    Tardocchi, M.; Pietropaolo, A.; Andreani, C.; Gorini, G.; Perelli-Cippo, E.; Rhodes, N.J.; Schooneveld, E.M.; Senesi, R.

    2004-01-01

    New perspectives for epithermal neutron spectroscopy are opened up by the recent developments of Resonance Detectors (RD) for inverse geometry time-of-flight spectrometers at pulsed neutron sources. The RD is based on the combination of an analyser foil used as neutron-to-gamma converter and a suitable photon detector. Here, we report on the state of the RD which is based on a YAP scintillator viewing a natural uranium analyser foil. The response of the YAP detector to the radiative capture γ emission from the uranium analyser foil has been characterized with a bi-parametric measurement of a reference Pb sample, which allowed simultaneous measurements of both neutron time-of-flight and γ pulse height (energy) spectra. The analysis of the γ pulse height and neutron time-of-flight spectra permitted to identify the signal and background components. These measurements showed that a significant improvement in the signal-to-background ratio can be achieved by setting a lower level discrimination on the photon energy at about 600keV. The first application of RD is the Very Low Angle Detector Bank (VLAD) which is planned to be installed in the next three years as an upgrade of the VESUVIO spectrometer, at the ISIS pulsed neutron source. VLAD will extend the (q,ω) kinematical to low wave vector transfers (q10A-1) coupled to high-energy transfers (-bar ω>1eV), which is still unexplored by neutron scattering experiments. The first measurements obtained on an ice sample with a VLAD prototype consisting of four RD units are presented here

  4. Study of human blood and hemocomponents irradiated by low angle x ray scattering (LAXS)

    International Nuclear Information System (INIS)

    Pinto, Nivia G. Villela; Barroso, Regina C.; Mota, Carla L.S.; Almeida, Andre P.; Azeredo, Soraia R.; Braz, Delson

    2009-01-01

    Irradiation of blood and blood components is currently practiced in developed and in a few developing countries. The main purpose of this process is the prevention of graft versus host disease in immunodeficient patients. The Food and Drug Administration recommends a dose range of 15 Gy to 25 Gy for these blood components. When x-ray photons are scattered from biological samples, their angular distribution shows one or more peaks in the forward direction of scattering. These peaks are characteristic for the investigated samples. Due to its wide range of biological and medical applications, low-angle x-ray scattering has attracted the attention of many authors. Thus in this present work was studied the possible variations in scattering profiles due to the irradiation when the gender of patients was considered. Fresh blood specimens were obtained from volunteers using vacutainer tubes containing EDTA, at the Dr. Eliel Figueiredo Laboratory, Rio de Janeiro. All the samples were lyophilized for 48 hours in a freeze drier in order to remove the water. The scattering measurements were carried out in e-2e reflection geometry using a powder diffractometer Shimadzu XRD- 6000. The measured characterization parameters for LAXS were associated with epidemiological data (gender). The mean values of the different parameters were compared using the Students's t-test for each characterization parameters. The scattering profiles from plasma and formed elements are characterized by the presence of two peaks in the forward direction of scattering. For epidemiological data (gender) analyzed was not found significant changes in the mostly of characterization parameters (p>0.05). (author)

  5. Development of new instrumentation for epithermal neutron scattering at very low angles

    Energy Technology Data Exchange (ETDEWEB)

    Tardocchi, M. [INFM, UdR Milano-Bicocca and Dipartimento di Fisica ' G.Occhialini' , Universita degli Studi di Milano-Bicocca, Pizza Della Scienza 3, Milan 20126 (Italy)]. E-mail: marco.tardocchi@mib.infn.it; Pietropaolo, A. [Dipartimento di Fisica, Universita degli Studi di Roma Tor Vergata and INFM, UdR Roma Tor Vergata, Rome (Italy); Andreani, C. [Dipartimento di Fisica, Universita degli Studi di Roma Tor Vergata and INFM, UdR Roma Tor Vergata, Rome (Italy); Gorini, G. [INFM, UdR Milano-Bicocca and Dipartimento di Fisica ' G.Occhialini' , Universita degli Studi di Milano-Bicocca, Pizza Della Scienza 3, Milan 20126 (Italy); Perelli-Cippo, E. [INFM, UdR Milano-Bicocca and Dipartimento di Fisica ' G.Occhialini' , Universita degli Studi di Milano-Bicocca, Pizza Della Scienza 3, Milan 20126 (Italy); Rhodes, N.J. [Isis Facility, Rutherford Appleton Laboratory, Chilton, Didcot (United Kingdom); Schooneveld, E.M. [Isis Facility, Rutherford Appleton Laboratory, Chilton, Didcot (United Kingdom); Senesi, R. [Dipartimento di Fisica, Universita degli Studi di Roma Tor Vergata and INFM, UdR Roma Tor Vergata, Rome (Italy)

    2004-12-11

    New perspectives for epithermal neutron spectroscopy are opened up by the recent developments of Resonance Detectors (RD) for inverse geometry time-of-flight spectrometers at pulsed neutron sources. The RD is based on the combination of an analyser foil used as neutron-to-gamma converter and a suitable photon detector. Here, we report on the state of the RD which is based on a YAP scintillator viewing a natural uranium analyser foil. The response of the YAP detector to the radiative capture {gamma} emission from the uranium analyser foil has been characterized with a bi-parametric measurement of a reference Pb sample, which allowed simultaneous measurements of both neutron time-of-flight and {gamma} pulse height (energy) spectra. The analysis of the {gamma} pulse height and neutron time-of-flight spectra permitted to identify the signal and background components. These measurements showed that a significant improvement in the signal-to-background ratio can be achieved by setting a lower level discrimination on the photon energy at about 600keV. The first application of RD is the Very Low Angle Detector Bank (VLAD) which is planned to be installed in the next three years as an upgrade of the VESUVIO spectrometer, at the ISIS pulsed neutron source. VLAD will extend the (q,{omega}) kinematical to low wave vector transfers (q10A-1) coupled to high-energy transfers (-bar {omega}>1eV), which is still unexplored by neutron scattering experiments. The first measurements obtained on an ice sample with a VLAD prototype consisting of four RD units are presented here.

  6. Determination of the contents of A- and B-starches in barley using low angle laser light scattering

    Czech Academy of Sciences Publication Activity Database

    Bohačenko, I.; Chmelík, Josef; Psota, V.

    2006-01-01

    Roč. 24, č. 1 (2006), s. 11-18 ISSN 1212-1800 R&D Projects: GA MZe QD1005 Institutional research plan: CEZ:AV0Z40310501 Keywords : starch * barley * low angle laser light scattering Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 0.387, year: 2006

  7. Plant growth promoters and methods of using them

    KAUST Repository

    Al-Babili, Salim

    2017-01-01

    New plant growth regulators, including compounds and compositions, and methods of use including for promoting root growth. The compounds are carotenoid oxidation products, and a preferred example is 3-OH--β-apo-13-Carotenone. A method comprising

  8. Method of Promoting Single Crystal Growth During Melt Growth of Semiconductors

    Science.gov (United States)

    Su, Ching-Hua (Inventor)

    2013-01-01

    The method of the invention promotes single crystal growth during fabrication of melt growth semiconductors. A growth ampoule and its tip have a semiconductor source material placed therein. The growth ampoule is placed in a first thermal environment that raises the temperature of the semiconductor source material to its liquidus temperature. The growth ampoule is then transitioned to a second thermal environment that causes the semiconductor source material in the growth ampoule's tip to attain a temperature that is below the semiconductor source material's solidus temperature. The growth ampoule so-transitioned is then mechanically perturbed to induce single crystal growth at the growth ampoule's tip.

  9. Crystal growth of emerald by flux method

    International Nuclear Information System (INIS)

    Inoue, Mikio; Narita, Eiichi; Okabe, Taijiro; Morishita, Toshihiko.

    1979-01-01

    Emerald crystals have been formed in two binary fluxes of Li 2 O-MoO 2 and Li 2 O-V 2 O 5 using the slow cooling method and the temperature gradient method under various conditions. In the flux of Li 2 O-MoO 3 carried out in the range of 2 -- 5 of molar ratios (MoO 3 /Li 2 O), emerald was crystallized in the temperature range from 750 to 950 0 C, and the suitable crystallization conditions were found to be the molar ratio of 3 -- 4 and the temperature about 900 0 C. In the flux of Li 2 O-V 2 O 5 carried out in the range of 1.7 -- 5 of molar ratios (V 2 O 5 /Li 2 O), emerald was crystallized in the temperature range from 900 to 1150 0 . The suitable crystals were obtained at the molar ratio of 3 and the temperature range of 1000 -- 1100 0 C. The crystallization temperature rised with an increase in the molar ratio of the both fluxes. The emeralds grown in two binary fluxes were transparent green, having the density of 2.68, the refractive index of 1.56, and the two distinct bands in the visible spectrum at 430 and 600nm. The emerald grown in Li 2 O-V 2 O 5 flux was more bluish green than that grown in Li 2 O-MoO 3 flux. The size of the spontaneously nucleated emerald grown in the former flux was larger than the latter, when crystallized by the slow cooling method. As for the solubility of beryl in the two fluxes, Li 2 O-V 2 O 5 flux was superior to Li 2 O-MoO 3 flux whose small solubility of SiO 2 caused an experimental problem to the temperature gradient method. The suitability of the two fluxes for the crystal growth of emerald by the flux method was discussed from the view point of various properties of above-mentioned two fluxes. (author)

  10. Faulting at Mormon Point, Death Valley, California: A low-angle normal fault cut by high-angle faults

    Science.gov (United States)

    Keener, Charles; Serpa, Laura; Pavlis, Terry L.

    1993-04-01

    New geophysical and fault kinematic studies indicate that late Cenozoic basin development in the Mormon Point area of Death Valley, California, was accommodated by fault rotations. Three of six fault segments recognized at Mormon Point are now inactive and have been rotated to low dips during extension. The remaining three segments are now active and moderately to steeply dipping. From the geophysical data, one active segment appears to offset the low-angle faults in the subsurface of Death Valley.

  11. Importance of low-angle grain boundaries in YBa2Cu3O7-δ coated conductors

    International Nuclear Information System (INIS)

    Durrell, J H; Rutter, N A

    2009-01-01

    Over the past ten years the perception of grain boundaries in YBa 2 Cu 3 O 7-δ conductors has changed greatly. They are now not a problem to be eliminated, but an inevitable and potentially favourable part of the material. This change has arisen as a consequence of new manufacturing techniques which result in excellent grain alignment, reducing the spread of grain boundary misorientation angles. At the same time there is considerable recent evidence which indicates that the variation of properties of grain boundaries with mismatch angle is more complex than a simple exponential decrease in critical current. This is due to the fact that low-angle grain boundaries represent a qualitatively different system to high-angle boundaries. The time is therefore right for a targeted review of research into low-angle YBa 2 Cu 3 O 7-δ grain boundaries. This article does not purport to be a comprehensive review of the physics of grain boundaries as found in YBa 2 Cu 3 O 7-δ in general; for a broader overview we would recommend that the reader consult the comprehensive review of Hilgenkamp and Mannhart (2002 Rev. Mod. Phys. 74 485). The purpose of this article is to review the origin and properties of the low-angle grain boundaries found in YBa 2 Cu 3 O 7-δ coated conductors both individually and as a collective system. (topical review)

  12. Growth of sphagnum: methods of measurement

    Energy Technology Data Exchange (ETDEWEB)

    Clymo, R S

    1970-01-01

    The results presented here show that the growth of sphagnum is at least comparable with other communities from the same area. It seems desirable to know more about the field microenvironment and about the response of the plants. It is not possible, for example, to account satisfactorily for such obvious features of bog topography as hummocks and pools.

  13. Bayesian methods to estimate urban growth potential

    Science.gov (United States)

    Smith, Jordan W.; Smart, Lindsey S.; Dorning, Monica; Dupéy, Lauren Nicole; Méley, Andréanne; Meentemeyer, Ross K.

    2017-01-01

    Urban growth often influences the production of ecosystem services. The impacts of urbanization on landscapes can subsequently affect landowners’ perceptions, values and decisions regarding their land. Within land-use and land-change research, very few models of dynamic landscape-scale processes like urbanization incorporate empirically-grounded landowner decision-making processes. Very little attention has focused on the heterogeneous decision-making processes that aggregate to influence broader-scale patterns of urbanization. We examine the land-use tradeoffs faced by individual landowners in one of the United States’ most rapidly urbanizing regions − the urban area surrounding Charlotte, North Carolina. We focus on the land-use decisions of non-industrial private forest owners located across the region’s development gradient. A discrete choice experiment is used to determine the critical factors influencing individual forest owners’ intent to sell their undeveloped properties across a series of experimentally varied scenarios of urban growth. Data are analyzed using a hierarchical Bayesian approach. The estimates derived from the survey data are used to modify a spatially-explicit trend-based urban development potential model, derived from remotely-sensed imagery and observed changes in the region’s socioeconomic and infrastructural characteristics between 2000 and 2011. This modeling approach combines the theoretical underpinnings of behavioral economics with spatiotemporal data describing a region’s historical development patterns. By integrating empirical social preference data into spatially-explicit urban growth models, we begin to more realistically capture processes as well as patterns that drive the location, magnitude and rates of urban growth.

  14. The application of low angle Rutherford backscattering and channelling techniques to determine implantation induced disorder profile distributions in semiconductors

    International Nuclear Information System (INIS)

    Ahmed, N.A.G.; Christodoulides, C.E.; Carter, G.; Nobes, M.J.; Titov, A.I.

    1980-01-01

    Low angle exit (9 0 ) Rutherford backscattering geometry and channelling of 2 MeV 4 He + are employed to investigate the disorder depth profiles created by 40 keV N + implantation in (111) silicon and (100) GaAs targets. Parameters which can influence the disordering rate and its spatial distribution, such as ion fluence flux, substrate type and substrate temperature are examined. Under certain implantation conditions, the damage profile distributions are asymmetric - exhibiting a bimodal form in silicon targets or confined much closer to the GaAs surface than the normally expected mean range of 40 keV N + ions. (orig.)

  15. A computed microtomography method for understanding epiphyseal growth plate fusion

    Science.gov (United States)

    Staines, Katherine A.; Madi, Kamel; Javaheri, Behzad; Lee, Peter D.; Pitsillides, Andrew A.

    2017-12-01

    The epiphyseal growth plate is a developmental region responsible for linear bone growth, in which chondrocytes undertake a tightly regulated series of biological processes. Concomitant with the cessation of growth and sexual maturation, the human growth plate undergoes progressive narrowing, and ultimately disappears. Despite the crucial role of this growth plate fusion ‘bridging’ event, the precise mechanisms by which it is governed are complex and yet to be established. Progress is likely hindered by the current methods for growth plate visualisation; these are invasive and largely rely on histological procedures. Here we describe our non-invasive method utilising synchrotron x-ray computed microtomography for the examination of growth plate bridging, which ultimately leads to its closure coincident with termination of further longitudinal bone growth. We then apply this method to a dataset obtained from a benchtop microcomputed tomography scanner to highlight its potential for wide usage. Furthermore, we conduct finite element modelling at the micron-scale to reveal the effects of growth plate bridging on local tissue mechanics. Employment of these 3D analyses of growth plate bone bridging is likely to advance our understanding of the physiological mechanisms that control growth plate fusion.

  16. Comparison of test methods for mould growth in buildings

    DEFF Research Database (Denmark)

    Bonderup, Sirid; Gunnarsen, Lars Bo; Knudsen, Sofie Marie

    2016-01-01

    renovation needs. This is of importance when hidden surface testing would require destructive measures and subsequent renovation. After identifying available methods on the Danish market for assessing mould growth in dwellings, a case study was conducted to test the usefulness of the methods in four......The purpose of this work is to compare a range of test methods and kits for assessing whether a building structure is infested by mould fungi. A further purpose of this work is to evaluate whether air-based methods for sampling fungal emissions provide information qualifying decisions concerning...... methods measure different aspects relating to mould growth and vary in selectivity and precision. The two types of air samples indicated low levels of mould growth, even where the results of the other methods indicated high to moderate growth. With methods based on culture and DNA testing some differences...

  17. Re-assessing copepod growth using the Moult Rate method

    DEFF Research Database (Denmark)

    Hirst, Andrew G.; Keister, J. E.; Richardson, A. J.

    2014-01-01

    Estimating growth and production rates of mesozooplankton, and copepods in particular, is important in describing flows of material and energy though pelagic systems. Over the past 30 years, the Moult Rate (MR) method has been used to estimate juvenile copepod growth rates in ∼40 papers. Yet the MR......-moulting stage, e.g. copepodite stage 5 to adult. We performed experiments with Calanus pacificus to estimate growth of stage C5 using an alternative method. We found that the error size and sign varied between mass type (i.e. DW, C and N). Recommendations for practical future assessments of growth in copepods...

  18. Methods for measuring arctic and alpine shrub growth

    DEFF Research Database (Denmark)

    Myers-Smith, Isla; Hallinger, Martin; Blok, Daan

    2015-01-01

    Shrubs have increased in abundance and dominance in arctic and alpine regions in recent decades. This often dramatic change, likely due to climate warming, has the potential to alter both the structure and function of tundra ecosystems. The analysis of shrub growth is improving our understanding...... of tundra vegetation dynamics and environmental changes. However, dendrochronological methods developed for trees, need to be adapted for the morphology and growth eccentricity of shrubs. Here, we review current and developing methods to measure radial and axial growth, estimate age, and assess growth...... dynamics in relation to environmental variables. Recent advances in sampling methods, analysis and applications have improved our ability to investigate growth and recruitment dynamics of shrubs. However, to extrapolate findings to the biome scale, future dendroecologicalwork will require improved...

  19. of different weed control methods on Weed infestation, growth

    African Journals Online (AJOL)

    thinkexploitsint'l

    This weed control method also resulted in significantly better growth and ... proper management, it is possible to obtain 2,500 kg ha-1 (Onwueme and Sinha, 1991). ... however, time consuming, labour – intensive, strenuous and generally ...

  20. Silicon crystal growth using a liquid-feeding Czochralski method

    Science.gov (United States)

    Shiraishi, Yutaka; Kurosaka, Shoei; Imai, Masato

    1996-09-01

    Silicon single crystals with uniformity along the growth direction were grown using a new continuous Czochralski (CCZ) method. Polycrystalline silicon rods used as charge materials are melted by carbon heaters over a crucible without contact between the raw material and other substances. Using this method, silicon crystals with diameters as large as 6 or 8 inch and good uniformity along the growth direction were grown.

  1. Production study of light fragments emitted at low angle in relativistic heavy ion collisions

    International Nuclear Information System (INIS)

    Bastid, N.

    1987-03-01

    The Diogene plastic wall was built in order to study fragment production in a 0 O -6 O angular range. After generalities on heavy ion collisions and a description of the Diogene detector, methods used for data analysis allowing identification of charged particles and measurement of their energy and emission angle are presented. From correlation studies between the Diogene events and the plastic wall events, we can have an information on the centrality of collisions. On the other hand, the study of differential cross sections shows two existing sources: one formed by the projectile remnant, at a velocity close to beam velocity and a source of intermediary rapidity formed by the participants. We have shown that even for very central collisions and heavy targets, the target nucleus remains partially transparent. In order to explain projectile fragmentation mechanism, we have used two models: a coalescence model and a thermal model. The first model gives the value of the coalescence radius. It seems that this model does not apply to angles nearing 0 O . With the thermal model, we have been able to sort out apparent temperature values which confirm the weak excitation energy of the projectile remnant [fr

  2. Critical current behaviour of YBCO thin films described by vortex pinning on low-angle domain boundaries and vortex creep

    International Nuclear Information System (INIS)

    Golovchanskiy, I.A.; Pan, A.V.; Fedoseev, S.A.; Shcherbakova, O.V.; Dou, S.X.

    2012-01-01

    A pinning potential for vortices was introduced assuming plastic pinning of vortex lattice on chains of out-of-plane individual edge dislocations that form low-angle domain boundaries in high quality YBa 2 Cu 3 O 7 thin films. Using this pinning potential with the classical Kim-Anderson vortex creep approach a model for critical current dependence on field has been successfully developed. The model shows a plausible description of J c (B a ) over the entire field range. Electrical field criterion is incorporated providing the ability to compare measurements made with different criteria (including different measurement techniques). Applicability of this model has been verified by experimental data obtained by direct transport and magnetisation measurements on high quality films grown by pulsed laser deposition. Pinning potential obtained from the fitting procedure is consistent with theoretical predictions. The model showed that the effective pinning landscape changes under influence of external conditions.

  3. Characterization of thin-film multilayers using magnetization curves and modeling of low-angle X-ray diffraction data

    Energy Technology Data Exchange (ETDEWEB)

    Lane, M. [Emory & Henry College, VA (United States); Chaiken, A.; Michel, R.P. [Lawrence Livermore National Lab., CA (United States)

    1994-12-01

    We have characterized thin-film multilayers grown by ion-beam sputtering using magnetization curves and modeling of low-angle x-ray diffraction data. In our films, we use ferromagnetic layer = Co, Fe, and NiFe and spacer layer = Si, Ge, FeSi{sub 2}, and CoSi{sub 2}. We have studied the effects of (1) deposition conditions; (2) thickness of layers; (3) different layer materials; and (4) annealing. We find higher magnetization in films grown at 1000V rather than 500V and in films with spacer layers of 50{angstrom} rather than 100{angstrom}. We find higher coercivity in films with cobalt grown on germanium rather than silicon, metal grown on gold underlayers rather than on glass substrates, and when using thinner spacer layers. Finally, modeling reveals that films grown with disilicide layers are more thermally stable than films grown with silicon spacer layers.

  4. Construction of the World Health Organization child growth standards: Selection of methods for attained growth curves

    NARCIS (Netherlands)

    Borghi, E.; Onis, M. de; Garza, C.; Broeck, J. van den; Frongillo, E.A.; Grummer-Strawn, L.; Buuren, S. van; Pan, H.; Molinari, L.; Martorell, R.; Onyango, A.W.; Martines, J.C.; Pinol, A.; Siyam, A.; Victoria, C.G.; Bhan, M.K.; Araújo, C.L.; Lartey, A.; Owusu, W.B.; Bhandari, N.; Norum, K.R.; Bjoerneboe, G.-E.Aa.; Mohamed, A.J.; Dewey, K.G.; Belbase, K.; Chumlea, C.; Cole, T.; Shrimpton, R.; Albernaz, E.; Tomasi, E.; Cássia Fossati da Silveira, R. de; Nader, G.; Sagoe-Moses, I.; Gomez, V.; Sagoe-Moses, C.; Taneja, S.; Rongsen, T.; Chetia, J.; Sharma, P.; Bahl, R.; Baerug, A.; Tufte, E.; Alasfoor, D.; Prakash, N.S.; Mabry, R.M.; Al Rajab, H.J.; Helmi, S.A.; Nommsen-Rivers, L.A.; Cohen, R.J.; Heinig, M.J.

    2006-01-01

    The World Health Organization (WHO), in collaboration with a number of research institutions worldwide, is developing new child growth standards. As part of a broad consultative process for selecting the best statistical methods, WHO convened a group of statisticians and child growth experts to

  5. Aluminum-catalyzed silicon nanowires: Growth methods, properties, and applications

    Energy Technology Data Exchange (ETDEWEB)

    Hainey, Mel F.; Redwing, Joan M. [Department of Materials Science and Engineering, Materials Research Institute, The Pennsylvania State University, University Park, Pennsylvania 16802 (United States)

    2016-12-15

    Metal-mediated vapor-liquid-solid (VLS) growth is a promising approach for the fabrication of silicon nanowires, although residual metal incorporation into the nanowires during growth can adversely impact electronic properties particularly when metals such as gold and copper are utilized. Aluminum, which acts as a shallow acceptor in silicon, is therefore of significant interest for the growth of p-type silicon nanowires but has presented challenges due to its propensity for oxidation. This paper summarizes the key aspects of aluminum-catalyzed nanowire growth along with wire properties and device results. In the first section, aluminum-catalyzed nanowire growth is discussed with a specific emphasis on methods to mitigate aluminum oxide formation. Next, the influence of growth parameters such as growth temperature, precursor partial pressure, and hydrogen partial pressure on nanowire morphology is discussed, followed by a brief review of the growth of templated and patterned arrays of nanowires. Aluminum incorporation into the nanowires is then discussed in detail, including measurements of the aluminum concentration within wires using atom probe tomography and assessment of electrical properties by four point resistance measurements. Finally, the use of aluminum-catalyzed VLS growth for device fabrication is reviewed including results on single-wire radial p-n junction solar cells and planar solar cells fabricated with nanowire/nanopyramid texturing.

  6. Geometry and evolution of low-angle normal faults (LANF) within a Cenozoic high-angle rift system, Thailand: Implications for sedimentology and the mechanisms of LANF development

    Science.gov (United States)

    Morley, Chris K.

    2009-10-01

    At least eight examples of large (5-35 km heave), low-angle normal faults (LANFs, 20°-30° dip) occur in the Cenozoic rift basins of Thailand and laterally pass into high-angle extensional fault systems. Three large-displacement LANFs are found in late Oligocene-Miocene onshore rift basins (Suphan Buri, Phitsanulok, and Chiang Mai basins), they have (1) developed contemporaneous with, or after the onset of, high-angle extension, (2) acted as paths for magma and associated fluids, and (3) impacted sedimentation patterns. Displacement on low-angle faults appears to be episodic, marked by onset of lacustrine conditions followed by axial progradation of deltaic systems that infilled the lakes during periods of low or no displacement. The Chiang Mai LANF is a low-angle (15°-25°), high-displacement (15-35 km heave), ESE dipping LANF immediately east of the late early Miocene Doi Inthanon and Doi Suthep metamorphic core complexes. Early Cenozoic transpressional crustal thickening followed by the northward motion of India coupled with Burma relative to east Burma and Thailand (˜40-30 Ma) caused migmatization and gneiss dome uplift in the late Oligocene of the core complex region, followed by LANF activity. LANF displacement lasted 4-6 Ma during the early Miocene and possibly transported a late Oligocene-early Miocene high-angle rift system 35 km east. Other LANFs in Thailand have lower displacements and no associated metamorphic core complexes. The three LANFs were initiated as low-angle faults, not by isostatic rotation of high-angle faults. The low-angle dips appear to follow preexisting low-angle fabrics (thrusts, shear zones, and other low-angle ductile foliations) predominantly developed during Late Paleozoic and early Paleogene episodes of thrusting and folding.

  7. Continuum damage mechanics method for fatigue growth of surface cracks

    International Nuclear Information System (INIS)

    Feng Xiqiao; He Shuyan

    1997-01-01

    With the background of leak-before-break (LBB) analysis of pressurized vessels and pipes in nuclear plants, the fatigue growth problem of either circumferential or longitudinal semi-elliptical surface cracks subjected to cyclic loading is studied by using a continuum damage mechanics method. The fatigue damage is described by a scalar damage variable. From the damage evolution equation at the crack tip, a crack growth equation similar to famous Paris' formula is derived, which shows the physical meaning of Paris' formula. Thereby, a continuum damage mechanics approach is developed to analyze the configuration evolution of surface cracks during fatigue growth

  8. Materials and methods to increase plant growth and yield

    Science.gov (United States)

    Kirst, Matias

    2017-05-16

    The present invention relates to materials and methods for modulating growth rates, yield, and/or resistance to drought conditions in plants. In one embodiment, a method of the invention comprises increasing expression of an hc1 gene (or a homolog thereof that provides for substantially the same activity), or increasing expression or activity of the protein encoded by an hc1 gene thereof, in a plant, wherein expression of the hc1 gene or expression or activity of the protein encoded by an hc1 gene results in increased growth rate, yield, and/or drought resistance in the plant.

  9. Effect of Growth Parameters on SnO2 Nanowires Growth by Electron Beam Evaporation Method

    Science.gov (United States)

    Rakesh Kumar, R.; Manjula, Y.; Narasimha Rao, K.

    2018-02-01

    Tin oxide (SnO2) nanowires were synthesized via catalyst assisted VLS growth mechanism by the electron beam evaporation method at a growth temperature of 450 °C. The effects of growth parameters such as evaporation rate of Tin, catalyst film thickness, and different types of substrates on the growth of SnO2 nanowires were studied. Nanowires (NWs) growth was completely seized at higher tin evaporation rates due to the inability of the catalyst particle to initiate the NWs growth. Nanowires diameters were able to tune with catalyst film thickness. Nanowires growth was completely absent at higher catalyst film thickness due to agglomeration of the catalyst film. Optimum growth parameters for SnO2 NWs were presented. Nanocomposites such as Zinc oxide - SnO2, Graphene oxide sheets- SnO2 and Graphene nanosheets-SnO2 were able to synthesize at a lower substrate temperature of 450 °C. These nanocompsoites will be useful in enhancing the capacity of Li-ion batteries, the gas sensing response and also useful in increasing the photo catalytic activity.

  10. Modeling error distributions of growth curve models through Bayesian methods.

    Science.gov (United States)

    Zhang, Zhiyong

    2016-06-01

    Growth curve models are widely used in social and behavioral sciences. However, typical growth curve models often assume that the errors are normally distributed although non-normal data may be even more common than normal data. In order to avoid possible statistical inference problems in blindly assuming normality, a general Bayesian framework is proposed to flexibly model normal and non-normal data through the explicit specification of the error distributions. A simulation study shows when the distribution of the error is correctly specified, one can avoid the loss in the efficiency of standard error estimates. A real example on the analysis of mathematical ability growth data from the Early Childhood Longitudinal Study, Kindergarten Class of 1998-99 is used to show the application of the proposed methods. Instructions and code on how to conduct growth curve analysis with both normal and non-normal error distributions using the the MCMC procedure of SAS are provided.

  11. A summary of the low angle x-ray atomic scattering factors which have been measured by the critical voltage effect in High Energy Electron Diffraction (HEED)

    International Nuclear Information System (INIS)

    Fox, A.G.; Fisher, R.M.

    1987-08-01

    A tabulated summary of all the accurate (/approximately/0.1%) low-angle x-ray atomic scattering (form) factors which have been determined by the systematic critical voltage technique in HEED is presented. For low atomic number elements (Z/approx lt/40) the low angle form factors can be significantly different to best free atom values, and so the best band structure calculated and/or x-ray measured form factors consistent with the critical voltage measurements are also indicated. At intermediate atomic numbers Z≅40→50 only the very low-angle form factors appear to be different to the best free atom values, and even then only by a small amount. For heavy elements (Z/approx lt/70) the best free atom form factors appear to agree very closely with the critical voltage measured values and so, in this case, critical voltage measurements give very accurate measurements of Debye-Waller factors. 48 refs

  12. Effect of Low Angle Grain Boundaries on Mechanical Properties of DD5 Single Crystal Ni-base Superalloy

    Directory of Open Access Journals (Sweden)

    QIN Jianchao

    2017-06-01

    Full Text Available The effects of low angle grain boundaries on the mechanical properties of second generation single crystal superalloy DD5 were investigated and the test specimens were prepared by using seeds. The results show that at 870 ℃, the yield strength and breaking strength showed no difference when the angle is below 16.1°. The elongation is higher than 15% when the angle is below 11.4°, but the elongation decreases quickly when angle is above 11.4°. At 980 ℃/250 MPa, the rupture life is higher than 130 h when the angle is below 5.1°, and decreased slowly when the angle is above 5.1°. The rupture life still remaines 85% when the angle is 14.8°. But the rupture life decreases quickly when the angle is above 14.8°.At 1093 ℃/158 MPa, the rupture life is higher than 30 h when the angle is below 5.1°, and decreases when the angle is above 5.1°.

  13. Development of the Very Low Angle Detector (VLAD) for detection of epithermal neutrons at low momentum transfers

    International Nuclear Information System (INIS)

    Tardocchi, M.; Andreani, C.; Cremonesi, O.; Gorini, G.; Perelli-Cippo, E.; Pietropaolo, A.; Rhodes, N.; Schooneveld, E.; Senesi, R.

    2006-01-01

    New perspectives for epithermal neutron spectroscopy are opened up by the recent development of new instrumentation for inverse geometry time of flight spectrometers at pulsed neutron sources. One example is the Very Low Angle Detector (VLAD) bank which will be installed as an upgrade of the VESUVIO neutron spectrometer, at the ISIS pulsed neutron source. VLAD is developed for detecting epithermal neutrons in the 1-100 eV energy range at very low scattering angles (l deg. - 5 deg.). VLAD will extend the kinematical region covered by today's neutron scattering experiments to the region of low wave vector transfers ( -1 ) and high energy transfers (>1 eV). Accessing such kinematical region will allow new experimental studies in condensed matter systems. The neutron detection is based on Resonance Detectors (RD), which consist of the combination of a resonance foil used as neutron-to-gamma converter and a photon detector. The results obtained with a prototype VLAD detector confirm the potential of this kind of experiments at scattering angles as low as 2 deg. - 5 deg. GEANT4 simulations are used to address issues, such as detector cross talk, which arise with the construction of compact RD arrays

  14. Late Neogene low-angle thrusting on the northwestern margin of the South Carpathians (Poiana Rusca, West Romania)

    Science.gov (United States)

    Oczlon, Martin S.; Onescu, Dan

    2005-12-01

    Mineral exploration drillholes and geoelectric prospecting provide for the first time evidence for thrusting of the South Carpathian Paleozoic basement over northerly adjacent Middle Miocene sediments. Investigations were carried out in two locations, 30 km apart, along the northern margin of the Poiana Rusca Mountains, Romania, southwestern Carpathians. Drill holes in both locations encountered weakly consolidated Middle Miocene clay, sand, and fine gravel below Paleozoic low-grade metamorphic rocks. Intersections from various drill holes demonstrate the presence of low-angle thrusting. Kinematic indicators are so far lacking, but with a thrust direction oriented roughly normal to strike of the Poiana Rusca Mountains, minimum displacement is 1-1.4 km in northwestern or northern direction, respectively. Thrusting occurred most likely during the Late Miocene-Pliocene, whereafter Quaternary regional uplift dissected the thrust plane. In the tectonic framework of Neogene dextral translation of the Tisza-Dacia Block against the southerly adjacent Moesian Platform, transtension appears responsible for Middle Miocene basin formation along the northern margin of the Poiana Rusca region. Proceeding collision of the Tisza-Dacia Block with the East European Craton introduced stronger impingement of the Tisza-Dacia Block against the Moesian Platform, leading to a Late Miocene-Pliocene transpressional regime, in which the northern Poiana Rusca basement was thrust over its adjacent Middle Miocene sediments.

  15. Interdiffusion in nanometer-scale multilayers investigated by in situ low-angle x-ray diffraction

    Science.gov (United States)

    Wang, Wei-Hua; Bai, Hai Yang; Zhang, Ming; Zhao, J. H.; Zhang, X. Y.; Wang, W. K.

    1999-04-01

    An in situ low-angle x-ray diffraction technique is used to investigate interdiffusion phenomena in various metal-metal and metal-amorphous Si nanometer-scale compositionally modulated multilayers (ML's). The temperature-dependent interdiffusivities are obtained by accurately monitoring the decay of the first-order modulation peak as a function of annealing time. Activation enthalpies and preexponential factors for the interdiffusion in the Fe-Ti, Ag-Bi, Fe-Mo, Mo-Si, Ni-Si, Nb-Si, and Ag-Si ML's are determined. Activation enthalpies and preexponential factors for the interdiffusion in the ML's are very small compared with that in amorphous alloys and crystalline solids. The relation between the atomic-size difference and interdiffusion in the ML's are investigated. The observed interdiffusion characteristics are compared with that in amorphous alloys and crystalline α-Zr, α-Ti, and Si. The experimental results suggest that a collective atomic-jumping mechanism govern the interdiffusion in the ML's, the collective proposal involving 8-15 atoms moving between extended nonequilibrium defects by thermal activation. The role of the interdiffusion in the solid-state reaction in the ML's is also discussed.

  16. Development of low angle grain boundaries in lightly deformed superconducting niobium and their influence on hydride distribution and flux perturbation

    Science.gov (United States)

    Sung, Z.-H.; Wang, M.; Polyanskii, A. A.; Santosh, C.; Balachandran, S.; Compton, C.; Larbalestier, D. C.; Bieler, T. R.; Lee, P. J.

    2017-05-01

    This study shows that low angle grain boundaries (LAGBs) can be created by small 5% strains in high purity (residual resistivity ratio ≥ 200) superconducting radio frequency (SRF)-grade single crystalline niobium (Nb) and that these boundaries act as hydrogen traps as indicated by the distribution of niobium hydrides (Nb1-xHx). Nb1-xHx is detrimental to SRF Nb cavities due to its normal conducting properties at cavity operating temperatures. By designing a single crystal tensile sample extracted from a large grain (>5 cm) Nb ingot slice for preferred slip on one slip plane, LAGBs and dense dislocation boundaries developed. With chemical surface treatments following standard SRF cavity fabrication practice, Nb1-xHx phases were densely precipitated at the LAGBs upon cryogenic cooling (8-10 K/min). Micro-crystallographic analysis confirmed heterogeneous hydride precipitation, which included significant hydrogen atom accumulation in LAGBs. Magneto-optical imaging analysis showed that these sites can then act as sites for both premature flux penetration and eventually flux trapping. However, this hydrogen related degradation at LAGBs did not completely disappear even after an 800 °C/2 h anneal typically used for hydrogen removal in SRF Nb cavities. These findings suggest that hydride precipitation at an LAGB is facilitated by a non-equilibrium concentration of vacancy-hydrogen (H) complexes aided by mechanical deformation and the hydride phase interferes with the recovery process under 800 °C annealing.

  17. Plant growth promoters and methods of using them

    KAUST Repository

    Al-Babili, Salim

    2017-01-05

    New plant growth regulators, including compounds and compositions, and methods of use including for promoting root growth. The compounds are carotenoid oxidation products, and a preferred example is 3-OH--β-apo-13-Carotenone. A method comprising promoting the growth of at least one plant with use of an effective amount of at least one composition comprising an effective amount of at least one compound which is represented by A-B-C, wherein B is a bivalent polyene moiety, A is a monovalent moiety linked to B by a six-membered carbon ring, wherein the ring has at least one substituent linked to the ring by an oxygen atom, and C is a monovalent moiety linked to B by a carbonyl group. Synergistic effects can be used with combinations of compounds.

  18. Quantification of the toxic hexavalent chromium content in an organic matrix by X-ray photoelectron spectroscopy (XPS) and ultra-low-angle microtomy (ULAM)

    Energy Technology Data Exchange (ETDEWEB)

    Greunz, Theresia, E-mail: theresia.greunz@jku.at [Christian Doppler Laboratory for Microscopic and Spectroscopic Material Characterisation (CDL-MS-MACH), Center for Surface and Nanoanalytics (ZONA), Johannes Kepler University Linz, Altenberger Straße 69, 4040 Linz (Austria); Duchaczek, Hubert; Sagl, Raffaela [voestalpine Stahl GmbH, voestalpine-Straße 3, 4031 Linz (Austria); Duchoslav, Jiri; Steinberger, Roland [Christian Doppler Laboratory for Microscopic and Spectroscopic Material Characterisation (CDL-MS-MACH), Center for Surface and Nanoanalytics (ZONA), Johannes Kepler University Linz, Altenberger Straße 69, 4040 Linz (Austria); Strauß, Bernhard [voestalpine Stahl GmbH, voestalpine-Straße 3, 4031 Linz (Austria); Stifter, David [Christian Doppler Laboratory for Microscopic and Spectroscopic Material Characterisation (CDL-MS-MACH), Center for Surface and Nanoanalytics (ZONA), Johannes Kepler University Linz, Altenberger Straße 69, 4040 Linz (Austria)

    2017-02-28

    Highlights: • Common methods are not suitable for a reliable determination of Cr(VI) in organic coatings on steel. • Our proposed method is a combination of XPS and ultra-low-angle microtomy (ULAM). • The results allow referring to legal regulations of the Cr(VI) concentration. • For this method no accurate sample parameters are required. - Abstract: Cr(VI) is known for its corrosion inhibitive properties and is, despite legal regulations, still a potential candidate to be added to thin (1–3 μm) protective coatings applied on, e.g., electrical steel as used for transformers, etc. However, Cr(VI) is harmful to the environment and to the human health. Hence, a reliable quantification of it is of decisive interest. Commonly, an alkaline extraction with a photometric endpoint detection of Cr(VI) is used for such material systems. However, this procedure requires an accurate knowledge on sample parameters such as dry film thickness and coating density that are occasionally associated with significant experimental errors. We present a comprehensive study of a coating system with a defined Cr(VI) pigment concentration applied on electrical steel. X-ray photoelectron spectroscopy (XPS) was employed to resolve the elemental chromium concentration and the chemical state. Turning to the fact that XPS is extremely surface sensitive (<10 nm) and that the lowest commonly achievable lateral resolution is a number of times higher than the coating thickness (∼2 μm), a bulk analysis was achieved with XPS line scans on extended wedge-shaped tapers through the coating. For that purpose a special sample preparation step performed on an ultra-microtome was required prior to analysis. Since a temperature increase leads to a reduction of Cr(VI) we extend our method on samples, which were subjected to different curing temperatures. We show that our proposed approach now allows to determine the elemental and Cr(VI) concentration and distribution inside the coating.

  19. Synthesis of lithium niobate and monocrystal growth by Czochralski method

    International Nuclear Information System (INIS)

    Balzuweit, K.

    1988-01-01

    The qualitative analysis of lithium niobate by x-ray analysis and optical microscopy is presented. The lithium niobate compound was obtained by synthesis using niobium oxides and lithium carbonates. The lithium niobate monocrystal growth was done by Czochralski method. (M.C.K.)

  20. A crack growth evaluation method for interacting multiple cracks

    International Nuclear Information System (INIS)

    Kamaya, Masayuki

    2003-01-01

    When stress corrosion cracking or corrosion fatigue occurs, multiple cracks are frequently initiated in the same area. According to section XI of the ASME Boiler and Pressure Vessel Code, multiple cracks are considered as a single combined crack in crack growth analysis, if the specified conditions are satisfied. In crack growth processes, however, no prescription for the interference between multiple cracks is given in this code. The JSME Post-Construction Code, issued in May 2000, prescribes the conditions of crack coalescence in the crack growth process. This study aimed to extend this prescription to more general cases. A simulation model was applied, to simulate the crack growth process, taking into account the interference between two cracks. This model made it possible to analyze multiple crack growth behaviors for many cases (e.g. different relative position and length) that could not be studied by experiment only. Based on these analyses, a new crack growth analysis method was suggested for taking into account the interference between multiple cracks. (author)

  1. Adjusting the general growth balance method for migration

    OpenAIRE

    Hill, Kenneth; Queiroz, Bernardo

    2010-01-01

    Death distribution methods proposed for death registration coverage by comparison with census age distributions assume no net migration. This assumption makes it problematic to apply these methods to sub-national and national populations affected by substantial net migration. In this paper, we propose and explore a two-step process in which the Growth Balance Equation is first used to estimate net migration rates, using a model of age-specific migration, and then it is used to compare the obs...

  2. Standard test method for creep-fatigue crack growth testing

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2010-01-01

    1.1 This test method covers the determination of creep-fatigue crack growth properties of nominally homogeneous materials by use of pre-cracked compact type, C(T), test specimens subjected to uniaxial cyclic forces. It concerns fatigue cycling with sufficiently long loading/unloading rates or hold-times, or both, to cause creep deformation at the crack tip and the creep deformation be responsible for enhanced crack growth per loading cycle. It is intended as a guide for creep-fatigue testing performed in support of such activities as materials research and development, mechanical design, process and quality control, product performance, and failure analysis. Therefore, this method requires testing of at least two specimens that yield overlapping crack growth rate data. The cyclic conditions responsible for creep-fatigue deformation and enhanced crack growth vary with material and with temperature for a given material. The effects of environment such as time-dependent oxidation in enhancing the crack growth ra...

  3. Analysis by low-angle neutron scattering of the structure of the acetylcholine receptor from Torpedo californica in detergent solution

    International Nuclear Information System (INIS)

    Wise, D.S.; Karlin, A.; Schoenborn, B.P.

    1979-01-01

    The acetylcholine receptor from the electric tissue of Torpedo californica is a large, integral membrane protein containing four different types of polypeptide chains. In this paper the results of the use of low-angle neutron scattering to investigate the shape of the receptor-detergent complex and separately of its protein and detergent moieties are reported. By adjustment of the neutron-scattering density of the solvent with D 2 O to match that of one or the other of the moieties, its contribution to the scattering can be nearly, if not completely, eliminated. Neutron scattering from Triton X-100 micelles established that this detergent is contrast matched in 18% D 2 O. Scattering measurements on the receptor-detergent complex in this solvent yielded a radius of gyration of the acetylcholine receptor monomer of 46 +- 1 A. The radius of gyration and molecular volume (305,000 A 3 ) of the receptor is inconsistent with a compact spherical shape. These parameters are consistent with, for example, a prolate cylinder of dimensions (length x diameter) 150 x 50 A or an oblate cylinder, 25 x 130 A. More complex shapes are possible and in fact seem to be required to reconcile the present results with previous electron microscopic and x-ray analyses of receptor in membrane and with considerations of the function of the receptor in controlling ion permeability. The neutron-scattering data yield, in addition, an independent determination of the molecular weight of the receptor protein (240,000 +- 40,000), the extent of Triton X-100 binding in the complex (0.4 g/g protein), and from the extended scattering curve, an approximation to the shape of the receptor-Triton X-100 complex, namely an oblate ellipsoid of axial ratio 1:4

  4. Principles of crystallization, and methods of single crystal growth

    International Nuclear Information System (INIS)

    Chacra, T.

    2010-01-01

    Most of single crystals (monocrystals), have distinguished optical, electrical, or magnetic properties, which make from single crystals, key elements in most of technical modern devices, as they may be used as lenses, Prisms, or grating sin optical devises, or Filters in X-Ray and spectrographic devices, or conductors and semiconductors in electronic, and computer industries. Furthermore, Single crystals are used in transducer devices. Moreover, they are indispensable elements in Laser and Maser emission technology.Crystal Growth Technology (CGT), has started, and developed in the international Universities and scientific institutions, aiming at some of single crystals, which may have significant properties and industrial applications, that can attract the attention of international crystal growth centers, to adopt the industrial production and marketing of such crystals. Unfortunately, Arab universities generally, and Syrian universities specifically, do not give even the minimum interest, to this field of Science.The purpose of this work is to attract the attention of Crystallographers, Physicists and Chemists in the Arab universities and research centers to the importance of crystal growth, and to work on, in the first stage to establish simple, uncomplicated laboratories for the growth of single crystal. Such laboratories can be supplied with equipment, which are partly available or can be manufactured in the local market. Many references (Articles, Papers, Diagrams, etc..) has been studied, to conclude the most important theoretical principles of Phase transitions,especially of crystallization. The conclusions of this study, are summarized in three Principles; Thermodynamic-, Morphologic-, and Kinetic-Principles. The study is completed by a brief description of the main single crystal growth methods with sketches, of equipment used in each method, which can be considered as primary designs for the equipment, of a new crystal growth laboratory. (author)

  5. Growth of large patterned arrays of neurons using plasma methods

    International Nuclear Information System (INIS)

    Brown, I G; Bjornstad, K A; Blakely, E A; Galvin, J E; Monteiro, O R; Sangyuenyongpipat, S

    2003-01-01

    To understand how large systems of neurons communicate, we need to develop, among other things, methods for growing patterned networks of large numbers of neurons. Success with this challenge will be important to our understanding of how the brain works, as well as to the development of novel kinds of computer architecture that may parallel the organization of the brain. We have investigated the use of metal ion implantation using a vacuum-arc ion source, and plasma deposition with a filtered vacuum-arc system, as a means of forming regions of selective neuronal attachment on surfaces. Lithographic patterns created by the treating surface with ion species that enhance or inhibit neuronal cell attachment allow subsequent proliferation and/or differentiation of the neurons to form desired patterned neural arrays. In the work described here, we used glass microscope slides as substrates, and some of the experiments made use of simple masks to form patterns of ion beam or plasma deposition treated regions. PC-12 rat neurons were then cultured on the treated substrates coated with Type I Collagen, and the growth and differentiation was monitored. Particularly good selective growth was obtained using plasma deposition of diamond-like carbon films of about one hundred Angstroms thickness. Neuron proliferation and the elaboration of dendrites and axons after the addition of nerve growth factor both showed excellent contrast, with prolific growth and differentiation on the treated surfaces and very low growth on the untreated surfaces

  6. Growth of large patterned arrays of neurons using plasma methods

    Energy Technology Data Exchange (ETDEWEB)

    Brown, I G; Bjornstad, K A; Blakely, E A; Galvin, J E; Monteiro, O R; Sangyuenyongpipat, S [Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States)

    2003-05-01

    To understand how large systems of neurons communicate, we need to develop, among other things, methods for growing patterned networks of large numbers of neurons. Success with this challenge will be important to our understanding of how the brain works, as well as to the development of novel kinds of computer architecture that may parallel the organization of the brain. We have investigated the use of metal ion implantation using a vacuum-arc ion source, and plasma deposition with a filtered vacuum-arc system, as a means of forming regions of selective neuronal attachment on surfaces. Lithographic patterns created by the treating surface with ion species that enhance or inhibit neuronal cell attachment allow subsequent proliferation and/or differentiation of the neurons to form desired patterned neural arrays. In the work described here, we used glass microscope slides as substrates, and some of the experiments made use of simple masks to form patterns of ion beam or plasma deposition treated regions. PC-12 rat neurons were then cultured on the treated substrates coated with Type I Collagen, and the growth and differentiation was monitored. Particularly good selective growth was obtained using plasma deposition of diamond-like carbon films of about one hundred Angstroms thickness. Neuron proliferation and the elaboration of dendrites and axons after the addition of nerve growth factor both showed excellent contrast, with prolific growth and differentiation on the treated surfaces and very low growth on the untreated surfaces.

  7. The effects of lower crustal strength and preexisting midcrustal shear zones on the formation of continental core complexes and low-angle normal faults

    KAUST Repository

    Wu, Guangliang; Lavier, Luc L.

    2016-01-01

    To investigate the formation of core complexes and low-angle normal faults, we devise thermomechanical simulations on a simplified wedge-like orogenic hinterland that has initial topography, Moho relief, and a preexisting midcrustal shear zone that can accommodate shear at very low angles (<20°). We mainly vary the strength of the lower crust and the frictional strength of the preexisting midcrustal shear zone. We find that the strength of the lower crust and the existence and strength of a preexisting shear zone significantly affect the formation and evolution of core complexes. With increasing lower crustal strength, we recognize varying extensional features with decreasing exhumation rate: these are characterized by bivergent metamorphic massifs, classic Cordilleran metamorphic core complexes, multiple consecutive core complexes (or boudinage structures), and a flexural core complex underlined by a large subsurface low-angle detachment fault with a small convex curvature. Topographic loading and mantle buoyancy forces, together with divergent boundaries, drive a regional lower crustal flow that leads to the exhumation of the lower crust where intensive upper crustal faulting induces strong unloading. The detachment fault is a decoupling zone that accommodates large displacement and accumulates sustained shear strain at very low angle between upper and lower crust. Though the regional stress is largely Andersonian, we find non-Andersonian stress in regions adjacent to the preexisting shear zone and those with high topographic gradient. Our new models provide a view that is generally consistent with geological and geophysical observations on how core complexes form and evolve.

  8. The effects of lower crustal strength and preexisting midcrustal shear zones on the formation of continental core complexes and low-angle normal faults

    KAUST Repository

    Wu, Guangliang

    2016-08-22

    To investigate the formation of core complexes and low-angle normal faults, we devise thermomechanical simulations on a simplified wedge-like orogenic hinterland that has initial topography, Moho relief, and a preexisting midcrustal shear zone that can accommodate shear at very low angles (<20°). We mainly vary the strength of the lower crust and the frictional strength of the preexisting midcrustal shear zone. We find that the strength of the lower crust and the existence and strength of a preexisting shear zone significantly affect the formation and evolution of core complexes. With increasing lower crustal strength, we recognize varying extensional features with decreasing exhumation rate: these are characterized by bivergent metamorphic massifs, classic Cordilleran metamorphic core complexes, multiple consecutive core complexes (or boudinage structures), and a flexural core complex underlined by a large subsurface low-angle detachment fault with a small convex curvature. Topographic loading and mantle buoyancy forces, together with divergent boundaries, drive a regional lower crustal flow that leads to the exhumation of the lower crust where intensive upper crustal faulting induces strong unloading. The detachment fault is a decoupling zone that accommodates large displacement and accumulates sustained shear strain at very low angle between upper and lower crust. Though the regional stress is largely Andersonian, we find non-Andersonian stress in regions adjacent to the preexisting shear zone and those with high topographic gradient. Our new models provide a view that is generally consistent with geological and geophysical observations on how core complexes form and evolve.

  9. Material and method for promoting the growth of anaerobic bacteria

    Science.gov (United States)

    Adler, Howard I.

    1984-01-01

    A material and method for promoting the growth of anaerobic bacteria which includes a nutrient media containing a hydrogen donor and sterile membrane fragments of bacteria having an electron transfer system which reduces oxygen to water. Dissolved oxygen in the medium is removed by adding the sterile membrane fragments to the nutrient medium and holding the medium at a temperature of about 10.degree. to about 60.degree. C. until the dissolved oxygen is removed.

  10. Overview of the Mechanics of the Active Mai'iu Low Angle Normal Fault (Dayman Dome), Southeastern Papua New Guinea

    Science.gov (United States)

    Little, T. A.; Boulton, C. J.; Webber, S. M.; Mizera, M.; Oesterle, J.; Ellis, S. M.; Norton, K. P.; Wallace, L.; Biemiller, J.; Seward, D.; Boles, A.

    2016-12-01

    The Mai'iu Fault is a corrugated low-angle normal fault (LANF) that has slipped >24 km. It emerges near sea level at 21° N dip, and flattens southward over the dome crest at 3000 m. This reactivated Paleogene suture is slipping at up to 1 cm/year based on previous GPS data and preliminary 10Be cosmogenic nuclide exposure scarp dating. An alignment of microseismicity (Eilon et al. 2015) suggests a dip of 30° N at 15-25 km depth. Pseudotachylites are abundant in lower, mylonitic parts of the footwall. One vein yielded 40Ar/39Ar ages of 1.9-2.2 Ma, implying seismicity at 8-10 km depth at the above slip rate. Widespread, antithetic normal faults in the footwall are attributed to rolling-hinge controlled yielding during exhumation. A single rider block is downfolded into synformal megamullion. Unconformities within this block, and ductile folding and conjugate strike-slip faulting of mylonitic footwall fabrics record prolonged EW shortening and constriction. Many normal and strike-slip faults cut the metabasaltic footwall recording Andersonian stresses and flipping between σ1 and σ2. To exhume the steep faults, the LANF must have remained active despite differential stress being locally high enough to initiate well-oriented faults—relationships that bracket the frictional strength of the LANF. Quantitative XRD on mafic and serpentinitic gouges reveal the Mai'iu fault core is enriched in weak clays corrensite and saponite. Hydrothermal friction experiments were done at effective normal stresses of 30-210 MPa, and temperatures of 50-450oC. At shallow depths (T≤200 oC), clay-rich fault gouges are frictionally weak (μ=0.13-0.15 and 0.20-0.28) and velocity-strengthening. At intermediate depths (T>200 oC), the footwall is frictionally strong (μ=0.71-0.78 and 0.50-0.64) and velocity-weakening. Velocity-strengthening is observed at T≥400 oC. The experiments provide evidence for deep unstable slip, consistent with footwall pseudotachylites and microseismicity at

  11. Silicon Crystal Growth by the Electromagnetic Czochralski (EMCZ) Method

    Science.gov (United States)

    Watanabe, Masahito; Eguchi, Minoru; Hibiya, Taketoshi

    1999-01-01

    A new method for growing silicon crystals by using electromagnetic force to rotate the melt without crucible rotation has been developed. We call it electromagnetic Czochralski (EMCZ) growth. An electromagnetic force in the azimuthal direction is generated in the melt by the interaction between an electric current (I) through the melt in the radial direction and a vertical magnetic field (B). The rotation rate (ωm) of the silicon melt is continuously changed from 0 to over 105 rpm under I = 0 to 8 A and B = 0 to 0.1 T. Thirty-mm-diameter silicon single crystals free of dislocations could be grown under two conditions: I = 2.0 A and B = 0.05 T (ωm = 105 rpm); and I =0.2 A and B = 0.1 T (ωm = 15 rpm). The oxygen concentration in the crystals was 8 ×1017 atoms/cm3 for the high rotation rate and 1×1017 atoms/cm3 for the low rotation rate. The oxygen-concentration distributions in the radial direction in both crystals were more homogeneous than those in the crystals grown by conventional CZ and/or MCZ growth. This new crystal-growth method can be easily adopted for growing large-diameter silicon crystals.

  12. Methods of assessing grain-size distribution during grain growth

    DEFF Research Database (Denmark)

    Tweed, Cherry J.; Hansen, Niels; Ralph, Brian

    1985-01-01

    This paper considers methods of obtaining grain-size distributions and ways of describing them. In order to collect statistically useful amounts of data, an automatic image analyzer is used, and the resulting data are subjected to a series of tests that evaluate the differences between two related...... distributions (before and after grain growth). The distributions are measured from two-dimensional sections, and both the data and the corresponding true three-dimensional grain-size distributions (obtained by stereological analysis) are collected. The techniques described here are illustrated by reference...

  13. Standard test method for measurement of fatigue crack growth rates

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2015-01-01

    1.1 This test method covers the determination of fatigue crack growth rates from near-threshold to Kmax controlled instability. Results are expressed in terms of the crack-tip stress-intensity factor range (ΔK), defined by the theory of linear elasticity. 1.2 Several different test procedures are provided, the optimum test procedure being primarily dependent on the magnitude of the fatigue crack growth rate to be measured. 1.3 Materials that can be tested by this test method are not limited by thickness or by strength so long as specimens are of sufficient thickness to preclude buckling and of sufficient planar size to remain predominantly elastic during testing. 1.4 A range of specimen sizes with proportional planar dimensions is provided, but size is variable to be adjusted for yield strength and applied force. Specimen thickness may be varied independent of planar size. 1.5 The details of the various specimens and test configurations are shown in Annex A1-Annex A3. Specimen configurations other than t...

  14. Radially converging tracer test in a low-angle fracture zone at the Finnsjoen site, central Sweden. The fracture zone project - phase 3

    International Nuclear Information System (INIS)

    Gustafsson, E.; Nordqvist, R.

    1993-10-01

    The performance and results of a radially converging tracer test in a low-angle major fracture zone in crystalline rock are described. The extensive, about 100 m thick, zone 2 was encountered by means of borehole investigations at depths ranging from 100 to 250 metres at the Finnsjon site, central eastern Sweden. The zone studied (zone 2) consists of highly conductive, metre thick interconnected minor shear and fracture zones (sub-zones) with low conductive rock in between. The objective of the tracer test was primarily to determine flow and transport characteristics in a major fracture zone. Secondly new equipment, experimental design and methods of interpretation were developed, tested and improved. The converging flow field was created by pumping in a central borehole from a packed-off interval enclosing the whole thickness of zone 2. Tracer breakthrough was registered from all nine injection points, with first arrivals ranging from 24 to 3200 hours. Evaluated flow and transport parameters included; flow porosity, dispersivity, flow wetted surface, fracture aperture and hydraulic conductivity in fracture flow paths. Directional variations were found in the flow and transport parameters determined, which is concluded to be due to heterogeneity and/or anisotropy. This conditions is more pronounced at depth in zone 2. The results from the tracer test also clearly show that the upper boundary of zone 2 is highly conductive and consistent over hundreds of metres. Within zone 2, and between upper and lower margins, interconnected discrete minor shear and fracture zones (sub-zones) constitute flow paths of considerable variable residence times. The dispersion within the sub-zones of zone 2, expressed as Peclet numbers ranged from 16 to 40. Flow porosity was determined to be 0.001-0.05 in the upper sub-zone and 0.01-0.1 in the intermediate and lower ones and flow wetted surface area per volume of rock was calculated to be within 1-92 m 2 /m 3 . 68 refs, 61 figs, 40 tabs

  15. Methods to obtain referral criteria in growth monitoring

    NARCIS (Netherlands)

    Van Dommelen, Paula; Van Buuren, Stef

    An important goal of growth monitoring is to identify genetic disorders, diseases or other conditions that manifest themselves through an abnormal growth. The two main conditions that can be detected by height monitoring are Turner's syndrome and growth hormone deficiency. Conditions or risk factors

  16. Methods for improved growth of group III nitride buffer layers

    Science.gov (United States)

    Melnik, Yurity; Chen, Lu; Kojiri, Hidehiro

    2014-07-15

    Methods are disclosed for growing high crystal quality group III-nitride epitaxial layers with advanced multiple buffer layer techniques. In an embodiment, a method includes forming group III-nitride buffer layers that contain aluminum on suitable substrate in a processing chamber of a hydride vapor phase epitaxy processing system. A hydrogen halide or halogen gas is flowing into the growth zone during deposition of buffer layers to suppress homogeneous particle formation. Some combinations of low temperature buffers that contain aluminum (e.g., AlN, AlGaN) and high temperature buffers that contain aluminum (e.g., AlN, AlGaN) may be used to improve crystal quality and morphology of subsequently grown group III-nitride epitaxial layers. The buffer may be deposited on the substrate, or on the surface of another buffer. The additional buffer layers may be added as interlayers in group III-nitride layers (e.g., GaN, AlGaN, AlN).

  17. Seismic images of an extensional basin, generated at the hangingwall of a low-angle normal fault: The case of the Sansepolcro basin (Central Italy)

    Science.gov (United States)

    Barchi, Massimiliano R.; Ciaccio, Maria Grazia

    2009-12-01

    The study of syntectonic basins, generated at the hangingwall of regional low-angle detachments, can help to gain a better knowledge of these important and mechanically controversial extensional structures, constraining their kinematics and timing of activity. Seismic reflection images constrain the geometry and internal structure of the Sansepolcro Basin (the northernmost portion of the High Tiber Valley). This basin was generated at the hangingwall of the Altotiberina Fault (AtF), an E-dipping low-angle normal fault, active at least since Late Pliocene, affecting the upper crust of this portion of the Northern Apennines. The dataset analysed consists of 5 seismic reflection lines acquired in the 80s' by ENI-Agip for oil exploration and a portion of the NVR deep CROP03 profile. The interpretation of the seismic profiles provides a 3-D reconstruction of the basin's shape and of the sedimentary succession infilling the basin. This consisting of up to 1200 m of fluvial and lacustrine sediments: this succession is much thicker and possibly older than previously hypothesised. The seismic data also image the geometry at depth of the faults driving the basin onset and evolution. The western flank is bordered by a set of E-dipping normal faults, producing the uplifting and tilting of Early to Middle Pleistocene succession along the Anghiari ridge. Along the eastern flank, the sediments are markedly dragged along the SW-dipping Sansepolcro fault. Both NE- and SW-dipping faults splay out from the NE-dipping, low-angle Altotiberina fault. Both AtF and its high-angle splays are still active, as suggested by combined geological and geomorphological evidences: the historical seismicity of the area can be reasonably associated to these faults, however the available data do not constrain an unambiguous association between the single structural elements and the major earthquakes.

  18. Standardization of heparins by means of high performance liquid chromatography equipped with a low angle laser light scattering detector

    NARCIS (Netherlands)

    Hennink, W.E.; van den Berg, J.W.A.; Feijen, Jan

    1987-01-01

    This study shows that HPLC-LALLS (high performance liquid chromatography with a light-scattering detector) is a convenient and reliable method for the characterization of standard heparin samples, provided that polyelectrolyte artefacts are suppressed by a suitable dialysis procedure. The method has

  19. Growth of uranyl hydroxide nanowires and nanotubes with electrodeposition method

    International Nuclear Information System (INIS)

    Wang Lin; Yuan Liyong; Chai Zhifang; Shi Weiqun

    2013-01-01

    Actinides nanomaterials have great potential applications in fabrication of novel nuclear fuel and spent fuel reprocessing in advanced nuclear energy system. However, the relative research so far still lacks systematic investigation on the synthetic methods for actinides nanomaterials. In this work, we use track-etched membranes as hard templates to synthesize uranium based nanomaterials with novel structures by electrodeposition method. Through electrochemical behavior investigations and subsequent product characterizations such as energy dispersive spectrometer (EDS), fourier transform infrared spectroscopy (FTIR), the chemical composition of deposition products have been confirmed as the uranyl hydroxide. More importantly, accurate control of morphology and structures (nanowires and nanotubes) could be achieved by carefully adjusting the growth parameters such as deposition time and deposition current density. It was found that the preferred morphology of electrodeposition products is nanowire when a low current density was applied, whereas nanotubes could be formed only under conditions of high current density and the short deposition time. The mechanism for the formation of nanowires in track-etched membranes is based on the precipitation of uranyl hydroxide from uranyl nitrate solution, according to the previous researches about obtaining nanostructures of hydroxides from nitrate salt solutions. And we have concluded that the formation of nanotubes is attributed to the hydrogen bubbles generated by water electrolysis under the condition of over-potential electro-reduction. The conveying of hydrogen bubbles plays the role of dynamic template which can prevent the complete filling of uranyl hydroxide in the channels. Additionally, we transform the chemical composition of deposition products from uranyl hydroxide to triuranium octoxide by calcining them at 500 and 800 degree centigrade, respectively, and SEM results show the morphologies of nanowires and

  20. The influence of erupting lateral teeth on maxillary anterior crowding in two Angle Class I maloclussion cases with high and low angles

    Directory of Open Access Journals (Sweden)

    Hiroshi Ueda

    2016-01-01

    Full Text Available Two cases of anterior crowding, both Skeletal Class I and Angle Class I maloclussion, one being low angle and the other high angle respectively, respectively, were treated and evaluated to ascertain whether or not there is a relationship among disproportionate mesial axial angulation of the maxillary lateral teeth and the Frankfurt Horizontal-Functional Occlusal plane, therefore generating maxillary anterior crowding. Both cases were Japanese boys, the first one aged 9 years 10 months with chief complaint being anterior crowding and the second case aged 7 years and 8 months complaining of inadequate space for satisfying canine eruption. During and after the second stage of orthodontic treatment on both cases, several radiographic analysis were performed to assess treatment progress and retention; from these radiographs, it was noticed among other findings that in the high-angle case, the axial angulations of the maxillary lateral incisors were markedly smaller than in the low-angle case, thus indicating mesial tipping in the upper dental arch. This decreased mesial axial angulation of the lateral teeth observed at high angles may potentially cause maxillary space deficiency.

  1. Hypothesis for the mechanics and seismic behaviour of low-angle normal faults: the example of the Altotiberina fault Northern Apennines

    Directory of Open Access Journals (Sweden)

    C. Collettini

    2002-06-01

    Full Text Available Widespread mapping of low-angle normal faults in areas of former continental extension continues to prompt debate as to whether such structures may be seismically active at very low dips (? <30 °in the upper continental crust.The Northern Apennines provide an example where an active low-angle normal fault (Altotiberina fault, ATFcan be studied.A set of commercial seismic reflection profiles plus deep boreholes have been used to constrain the geometry of the fault at depth.These data have been integrated with a microseismic survey showing that part of the microseismicity (M <3.0is consistent with the geometry of the ATF as imaged by depth converted seismic reflection profiles.Frictional fault mechanics under Byerlee ?s friction coefficient and vertical ? 1 (constrained from the inversion of the focal mechanismsdefines the peculiar condition for reactivation of the ATF:small values of differential stress,? 1 ?? 3 <28 MPa,relatively high value of tensile strength of the fault surrounding rocks (T ~10 MPaand tensile fluid overpressure P f >? 3 (i.e.? v >0.93.The short-lived attainment of P f >? 3 along small fault portions,in an area characterised by large amounts of CO2,account for the microseismic activity located along the ATF,which occurs on rupture surfaces in the range of 10 ??10 ? 3 km 2..

  2. Simplified method of computation for fatigue crack growth

    International Nuclear Information System (INIS)

    Stahlberg, R.

    1978-01-01

    A procedure is described for drastically reducing the computation time in calculating crack growth for variable-amplitude fatigue loading when the loading sequence is periodic. By the proposed procedure, the crack growth, r, per loading is approximated as a smooth function and its reciprocal is integrated, rather than summing crack growth cycle by cycle. The savings in computation time results since only a few pointwise values of r must be computed to generate an accurate interpolation function for numerical integration. Further time savings can be achieved by selecting the stress intensity coefficient (stress intensity divided by load) as the argument of r. Once r has been obtained as a function of stress intensity coefficient for a given material, environment, and loading sequence, it applies to any configuration of cracked structure. (orig.) [de

  3. Influence of vortex-vortex interaction on critical currents across low-angle grain boundaries in YBa2Cu3O7-δ thin films

    Science.gov (United States)

    Albrecht, J.; Leonhardt, S.; Kronmüller, H.

    2001-01-01

    Low-angle grain boundaries with misorientation angles θ<5° in optimally doped thin films of YBa2Cu3O7-δ are investigated by magneto-optical imaging. By using a numerical inversion scheme of Biot-Savart's law, the critical current density across the grain boundary can be determined with a spatial resolution of about 5μm. Detailed investigation of the spatially resolved flux density and current density data shows that the current density across the boundary varies with varying local flux density. Combining the corresponding flux and current pattern, it is found that there exists a universal dependency of the grain boundary current on the local flux density. Considering the magnetic vortex-vortex interaction in and in the vicinity of the grain boundary, a model is developed that is able to describe the experimental data.

  4. The O H stretching band in ice Ih derived via eV neutron spectroscopy on VESUVIO using the new very low angle detector bank

    Science.gov (United States)

    Perelli-Cippo, E.; Gorini, G.; Tardocchi, M.; Andreani, C.; Pietropaolo, A.; Senesi, R.; Rhodes, N. J.; Schooneveld, E. M.

    2006-06-01

    Strong demand exists for an experimental facility enabling new experimental investigations on condensed matter systems based on epithermal neutron scattering at high energy and low momentum transfers. This need will be met by the very low angle detector (VLAD) bank, to be installed on the VESUVIO spectrometer at the ISIS spallation neutron source. The equipment will operate in the scattering angular range 1°<2θ<5°. Scattering measurements from a polycrystalline ice sample using a VLAD prototype demonstrates the effectiveness of the detection technique adopted for the construction of the full detector array. The resulting density of states in ice is 9±2 atoms/cell, in agreement with previous measurements.

  5. Growth of lead molybdate crystals by vertical Bridgman method

    Indian Academy of Sciences (India)

    Unknown

    The seeds were put in the seed wells, then the feed materials were filled in the cylinder of crucibles. The assembled crucible was sealed in order to prevent the volatilization of the melt during crystal growth. The cru- cible was installed in a refractory tube filled with Al2O3 powder to isolate it from external temperature fluctua-.

  6. Methods for measuring arctic and alpine shrub growth: A review

    NARCIS (Netherlands)

    Myers-Smith, I.H.; Hallinger, M.; Blok, D.; Sass-Klaassen, U.G.W.; Rayback, S.A.

    2015-01-01

    Shrubs have increased in abundance and dominance in arctic and alpine regions in recent decades. This often dramatic change, likely due to climate warming, has the potential to alter both the structure and function of tundra ecosystems. The analysis of shrub growth is improving our understanding of

  7. Inclusion free cadmium zinc tellurium and cadmium tellurium crystals and associated growth method

    Science.gov (United States)

    Bolotnikov, Aleskey E [South Setauket, NY; James, Ralph B [Ridge, NY

    2010-07-20

    The present disclosure provides systems and methods for crystal growth of cadmium zinc tellurium (CZT) and cadmium tellurium (CdTe) crystals with an inverted growth reactor chamber. The inverted growth reactor chamber enables growth of single, large, high purity CZT and CdTe crystals that can be used, for example, in X-ray and gamma detection, substrates for infrared detectors, or the like. The inverted growth reactor chamber enables reductions in the presence of Te inclusions, which are recognized as an important limiting factor in using CZT or CdTe as radiation detectors. The inverted growth reactor chamber can be utilized with existing crystal growth techniques such as the Bridgman crystal growth mechanism and the like. In an exemplary embodiment, the inverted growth reactor chamber is a U-shaped ampoule.

  8. Methods of forecasting crack growth rate under creep conditions

    International Nuclear Information System (INIS)

    Ol'kin, S.I.

    1979-01-01

    Using construction aluminium alloy application possibility of linear mechanics of the destruction for quantitative description of crack development process under creepage conditions is investigated. It is shown, that the grade dependence between the stress intensity coefficient and the crack growth rate takes place only at certain combination of the sample geometry and creepage parameters, and consequently, its applicability in every given case must necessarily be tested experimentally

  9. Insulin-like growth factors: assay methods and their implications

    International Nuclear Information System (INIS)

    Guyda, H.J.; Posner, B.I.; Schiffrin, A.; Rappaport, R.; Postel-Vinay, M.C.; Corvol, M.T.

    1981-01-01

    The insulin-like growth factors (IGF's) are small molecular weight peptides (6-10 x 10 3 daltons) that circulate in blood plasma almost entirely bound to macromolecular carrier proteins. The growth-promoting and insulin-like activities of IGF's can be explained by the observed ability of these peptides to interact with the IGF receptor on the one hand and with the insulin receptor on the other. These observations have led to the establishment of radioreceptor assays (RRA's), competitive protein binding assays (CPBA's), and more recently radioimmunoassays (RIA's) for the IGF's that have different specificities. Because of their ease of performance and sensitivity, the radioligand assays have largely supplanted the biological assays originally utilized to identify and characterize these anabolic peptides. In this report the authors' studies are summarised which utilize a slightly acidic IGF which has been purified on the basis of its insulin-like activity in an insulin RRA and which was termed ILAs. They refer to purified insulin-like peptides that have the properties of a somatomedin by the generic term insulin-like growth factor (IGF). Somatomedin (SM) activity will be utilized to connote that activity in plasma or serum determined by bioassay. The competitive dose-response curves for IGF peptides in the insulin RRA as well as those in the ILAs RRA are presented. A combination of bioassays, RRA and RIA were employed to assess somatomedin activity and IGF peptide levels in a number of clinical circumstances. The correlations are discussed. (Auth.)

  10. METHOD FOR EVALUATING MOLD GROWTH ON CEILING TILE

    Science.gov (United States)

    A method to extract mold spores from porous ceiling tiles was developed using a masticator blender. Ceiling tiles were inoculated and analyzed using four species of mold. Statistical analysis comparing results obtained by masticator extraction and the swab method was performed. T...

  11. Prior approval: the growth of Bayesian methods in psychology.

    Science.gov (United States)

    Andrews, Mark; Baguley, Thom

    2013-02-01

    Within the last few years, Bayesian methods of data analysis in psychology have proliferated. In this paper, we briefly review the history or the Bayesian approach to statistics, and consider the implications that Bayesian methods have for the theory and practice of data analysis in psychology.

  12. Measurement of fatigue crack growth rate of reactor structural material in air based on DCPD method

    International Nuclear Information System (INIS)

    Du Donghai; Chen Kai; Yu Lun; Zhang Lefu; Shi Xiuqiang; Xu Xuelian

    2014-01-01

    The principles and details of direct current potential drop (DCPD) in monitoring the crack growth of reactor structural materials was introduced in this paper. Based on this method, the fatigue crack growth rate (CGR) of typical structural materials in nuclear power systems was measured. The effects of applied load, load ratio and loading frequency on the fatigue crack growth rate of reactor structural materials were discussed. The result shows that the fatigue crack growth rate of reactor structural materials depends on the hardness of materials, and the harder the material is, the higher the rate of crack growth is. (authors)

  13. A hydroponic method for plant growth in microgravity

    Science.gov (United States)

    Wright, B. D.

    1985-01-01

    A hydroponic apparatus under development for long-term microgravity plant growth is described. The capillary effect root environment system (CERES) is designed to keep separate the nutrient and air flows, although both must be simultaneously available to the roots. Water at a pressure slightly under air pressure is allowed to seep into a plastic depression covered by a plastic screen and a porous membrane. A root in the air on the membrane outer surface draws the moisture through it. The laboratory model has a wire-based 1.241 mm mesh polyethylene screen and a filter membrane with 0.45 micron pores, small enough to prohibit root hair penetration. The design eliminates the need to seal-off the plant environment. Problems still needing attention include scaling up of the CERES size, controlling biofouling of the membrane, and extending the applications to plants without fibrous root systems.

  14. Detecting long-term growth trends using tree rings: a critical evaluation of methods.

    Science.gov (United States)

    Peters, Richard L; Groenendijk, Peter; Vlam, Mart; Zuidema, Pieter A

    2015-05-01

    Tree-ring analysis is often used to assess long-term trends in tree growth. A variety of growth-trend detection methods (GDMs) exist to disentangle age/size trends in growth from long-term growth changes. However, these detrending methods strongly differ in approach, with possible implications for their output. Here, we critically evaluate the consistency, sensitivity, reliability and accuracy of four most widely used GDMs: conservative detrending (CD) applies mathematical functions to correct for decreasing ring widths with age; basal area correction (BAC) transforms diameter into basal area growth; regional curve standardization (RCS) detrends individual tree-ring series using average age/size trends; and size class isolation (SCI) calculates growth trends within separate size classes. First, we evaluated whether these GDMs produce consistent results applied to an empirical tree-ring data set of Melia azedarach, a tropical tree species from Thailand. Three GDMs yielded similar results - a growth decline over time - but the widely used CD method did not detect any change. Second, we assessed the sensitivity (probability of correct growth-trend detection), reliability (100% minus probability of detecting false trends) and accuracy (whether the strength of imposed trends is correctly detected) of these GDMs, by applying them to simulated growth trajectories with different imposed trends: no trend, strong trends (-6% and +6% change per decade) and weak trends (-2%, +2%). All methods except CD, showed high sensitivity, reliability and accuracy to detect strong imposed trends. However, these were considerably lower in the weak or no-trend scenarios. BAC showed good sensitivity and accuracy, but low reliability, indicating uncertainty of trend detection using this method. Our study reveals that the choice of GDM influences results of growth-trend studies. We recommend applying multiple methods when analysing trends and encourage performing sensitivity and reliability

  15. Growth

    Science.gov (United States)

    John R. Jones; George A. Schier

    1985-01-01

    This chapter considers aspen growth as a process, and discusses some characteristics of the growth and development of trees and stands. For the most part, factors affecting growth are discussed elsewhere, particularly in the GENETICS AND VARIATION chapter and in chapters in PART 11. ECOLOGY. Aspen growth as it relates to wood production is examined in the WOOD RESOURCE...

  16. The role of Gd-enhanced three-dimensional MRI fast low-angle shot (FLASH) in the evaluation of symptomatic lumbosacral nerve roots

    Energy Technology Data Exchange (ETDEWEB)

    Kikkawa, Ichiro; Sugimoto, Hideharu; Saita, Kazuo; Ookami, Hitoshi; Nakama, Sueo; Hoshino, Yuichi [Jichi Medical School, Minamikawachi, Tochigi (Japan)

    2001-07-01

    In the field of lumbar spine disorders, three-dimensional (3-D) magnetic resonance imaging (MRI) can clearly depict a lumbar nerve root from the distal region to the dorsal root ganglion. In this study, we used a gadoliniumdiethylenetriaminepentaacetic acid (Gd-DTPA) enhanced-three-dimensional (3-D) fast low-angle shot (FLASH) sequence when examining lumbosacral disorders. The subjects were 33 patients (14 men and 19 women) in whom lumbosacral neural compression had been diagnosed clinically. Twenty-one patients had lumbar disc herniation, 11 had lumbar spinal stenosis, and 1 had lumbar radiculopathy caused by rheumatoid arthritis. Five subjects with low back pain were also studied as a control group. In all patients and in all 5 of the controls, the dorsal root ganglion of every root was enhanced clearly. There was no root enhancement in the 5 controls. Enhancement of the symptomatic nerve roots, caused by compression, was found in 11 of the 33 patients. All 11 patients had rediculopathy, and muscle weakness was more frequent in patients with enhanced nerve roots than in those without enhancement. There was no enhancement of the cauda equina, even in the patients with cauda syndrome. The enhancement effect may reflect some pathological condition of the compressed nerve root and needs to be studied further. (author)

  17. The role of Gd-enhanced three-dimensional MRI fast low-angle shot (FLASH) in the evaluation of symptomatic lumbosacral nerve roots

    International Nuclear Information System (INIS)

    Kikkawa, Ichiro; Sugimoto, Hideharu; Saita, Kazuo; Ookami, Hitoshi; Nakama, Sueo; Hoshino, Yuichi

    2001-01-01

    In the field of lumbar spine disorders, three-dimensional (3-D) magnetic resonance imaging (MRI) can clearly depict a lumbar nerve root from the distal region to the dorsal root ganglion. In this study, we used a gadoliniumdiethylenetriaminepentaacetic acid (Gd-DTPA) enhanced-three-dimensional (3-D) fast low-angle shot (FLASH) sequence when examining lumbosacral disorders. The subjects were 33 patients (14 men and 19 women) in whom lumbosacral neural compression had been diagnosed clinically. Twenty-one patients had lumbar disc herniation, 11 had lumbar spinal stenosis, and 1 had lumbar radiculopathy caused by rheumatoid arthritis. Five subjects with low back pain were also studied as a control group. In all patients and in all 5 of the controls, the dorsal root ganglion of every root was enhanced clearly. There was no root enhancement in the 5 controls. Enhancement of the symptomatic nerve roots, caused by compression, was found in 11 of the 33 patients. All 11 patients had rediculopathy, and muscle weakness was more frequent in patients with enhanced nerve roots than in those without enhancement. There was no enhancement of the cauda equina, even in the patients with cauda syndrome. The enhancement effect may reflect some pathological condition of the compressed nerve root and needs to be studied further. (author)

  18. Growth of Cu thin films by the successive ionic layer adsorption and reaction (SILAR) method

    International Nuclear Information System (INIS)

    Lindroos, S.; Ruuskanen, T.; Ritala, M.; Leskelae, M.

    2004-01-01

    Copper thin films were grown on reduced indium tin oxide, molybdenum and polymer substrates using successive ionic layer adsorption and reaction (SILAR) method. Copper films were grown sequentially in a controlled way using simple copper salt and basic solution of formaldehyde as precursors. The copper films were polycrystalline with no preferred orientation as characterised by X-ray diffraction. On all substrates, the growth was clearly island growth in the beginning but after the whole surface was covered, the growth was more homogeneous

  19. Sensitive double-antibody method for simultaneous determination of insulin and growth hormone

    International Nuclear Information System (INIS)

    Koparanova, O.; Sotirov, G.; Tyrkolev, N.

    1982-01-01

    A method is described for simultaneous determination of insulin and growth hormone in one sample, using double-antibody technique. The method is characterized by appreciable sensitivity (2.5 μE/ml for insulin and a.2 ng/ml for growth hormone), exactness (variation quotient 6-16 per cent) and reproducibility (96.9-117 per cent). There was no statistically significant difference in the insulin and growth hormone values of the same sera, determined by the here suggested and the standard methods. The necessary test material for examination of either hormone is minimal (0.2 ml). One may thus extend the possibilities for radioimmunologic determination of insulin and growth hormone, when only minor amounts of serum or other biological fluid are available. The method is also less time consuming. Results are reported of statistical processing of an experimental model and different sera determined by the standard method and the one described by the authors. (author)

  20. Comparison of Fluorescence Microscopy and Different Growth Media Culture Methods for Acanthamoeba Keratitis Diagnosis.

    Science.gov (United States)

    Peretz, Avi; Geffen, Yuval; Socea, Soergiu D; Pastukh, Nina; Graffi, Shmuel

    2015-08-01

    Acanthamoeba keratitis (AK), a potentially blinding infection of the cornea, is caused by a free-living protozoan. Culture and microscopic examination of corneal scraping tissue material is the conventional method for identifying Acanthamoeba. In this article, we compared several methods for AK diagnosis of 32 patients: microscopic examination using fluorescent dye, specific culture on growth media-non-nutrient agar (NNA), culture on liquid growth media-peptone yeast glucose (PYG), and TYI-S-33. AK was found in 14 patients. Thirteen of the specimens were found AK positive by fluorescence microscopic examination, 11 specimens were found AK positive on PYG growth media, and 9 specimens were found AK positive on TYI-S-33 growth media. Only five specimens were found AK positive on NNA growth media. Therefore, we recommend using fluorescence microscopy technique and culture method, especially PYG liquid media. © The American Society of Tropical Medicine and Hygiene.

  1. New synthesis method for the growth of epitaxial graphene

    Energy Technology Data Exchange (ETDEWEB)

    Yu, X.Z. [Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Laboratory of Condensed Matter Spectroscopy and Opto-Electronic Physics, Department of Physics, Shanghai Jiao Tong University, 1954 Hua Shan Road, Shanghai 200030 (China); Hwang, C.G.; Jozwiak, C.M.; Koehl, A. [Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Schmid, A.K. [National Center for Electron Microscopy, Lawrence Berkeley National Laboratory, Berkeley, CA 94709 (United States); Lanzara, A., E-mail: ALanzara@lbl.gov [Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Department of Physics, University of California, Berkeley, CA 94720 (United States)

    2011-04-15

    Highlights: {yields} We report a new straightforward method for the synthesis of micrometer scale graphene sheets. {yields} The process is based on a face to face mehtod in which two SiC substrates are placed one on top of the other and are heated simultaneously, leading to highly homogeneous samples. {yields} The number of graphene layers is determined by the annealing temperature. - Abstract: As a viable candidate for an all-carbon post-CMOS electronics revolution, epitaxial graphene has attracted significant attention. To realize its application potential, reliable methods for fabricating large-area single-crystalline graphene domains are required. A new way to synthesize high quality epitaxial graphene, namely 'face-to-face' method, has been reported in this paper. The structure and morphologies of the samples are characterized by low-energy electron diffraction, atomic force microscopy, angle-resolved photoemission spectroscopy and Raman spectroscopy. The grown samples show better quality and larger length scales than samples grown through conventional thermal desorption. Moreover, the graphene thickness can be easily controlled by changing annealing temperature.

  2. Monitoring crack growth by a potential drop method

    International Nuclear Information System (INIS)

    Tomlinson, J.R.

    1978-01-01

    A theoretical model has been developed for the surface current flow and potential distribution around a surface breaking crack. This model's predictions have been confirmed in the laboratory and the method applied on site. It proved possible by careful design and rigorous testing to overcome the problems of interference in an electrically noisy environment. The principal weaknesses of the technique are that it is only capable of detecting cracks that break the accessible surface of the component, and that there may be problems with conductive bridging across the crack. On the other hand, the lack of any sophisticated probe in contact with the component makes the method suitable for high temperature use, and, being an electrical method, it is capable of continuous use. The use of a.c., as opposed to d.c., enables lower currents to be used. Given good access to the crack tip, a high sensitivity can be obtained, which enables noise rejection to be achieved with the use of a high threshold. (orig.) [de

  3. Floating Silicon Method

    Energy Technology Data Exchange (ETDEWEB)

    Kellerman, Peter

    2013-12-21

    The Floating Silicon Method (FSM) project at Applied Materials (formerly Varian Semiconductor Equipment Associates), has been funded, in part, by the DOE under a “Photovoltaic Supply Chain and Cross Cutting Technologies” grant (number DE-EE0000595) for the past four years. The original intent of the project was to develop the FSM process from concept to a commercially viable tool. This new manufacturing equipment would support the photovoltaic industry in following ways: eliminate kerf losses and the consumable costs associated with wafer sawing, allow optimal photovoltaic efficiency by producing high-quality silicon sheets, reduce the cost of assembling photovoltaic modules by creating large-area silicon cells which are free of micro-cracks, and would be a drop-in replacement in existing high efficiency cell production process thereby allowing rapid fan-out into the industry.

  4. Conformal growth method of ferroelectric materials for multifunctional composites

    Science.gov (United States)

    Bowland, Christopher Charles

    Multifunctional composites are the next generation of composites and aim to simultaneously meet multiple performance objectives to create system-level performance enhancements. Current fiber-reinforced composites have offered improved efficiency and performance through weight reduction and increased strength. However, these composites satisfy singular performance objectives. Therefore, the concept of multifunctional composites was developed as an approach to create components in a system that serve multiple functions. These composites aim to reduce the required components in a system by integrating unifunctional components together thus reducing the weight and complexity of the system as a whole. This work offers an approach to create multifunctional composites through the development of a structural, multifunctional fiber. This is achieved by synthesizing a ferroelectric material on the surface of carbon fiber. In this work, a two-step hydrothermal reaction is developed for synthesizing a conformal film of barium titanate (BaTiO3) on the surface of carbon fiber. A fundamental understanding of this hydrothermal process is performed on planar substrates leading to the development of processing parameters that result in epitaxial-type growth of highly-aligned BaTiO3 nanowires. This work establishes the hydrothermal reaction as a powerful synthesis technique for generating nanostructured BaTiO3 on carbon fiber creating a novel, multifunctional fiber. A reaction optimization process leads to the development of parameters that stabilize tetragonal phase BaTiO3 without the need for subsequent heat treatments. The application potential of these fibers is illustrated with both single fibers and woven fabrics. Single fiber cantilever beams are fabricated and subjected to vibrations to determine its voltage output with the ultimate goal of producing an air flow sensor. Carbon fiber reinforced composite integration is carried out by scaling up the hydrothermal reaction to

  5. Methods for growth regulation of greenhouse produced ornamental pot- and bedding plants – a current review

    Directory of Open Access Journals (Sweden)

    Bergstrand Karl-Johan I.

    2017-06-01

    Full Text Available Chemical plant growth regulators (PGRs are used in the production of ornamental potted and bedding plants. Growth control is needed for maximizing production per unit area, reducing transportation costs and to obtain a desired visual quality. However, the use of PGRs is associated with toxicity risks to humans and the environment. In many countries the availability of PGRs is restricted as few substances are registered for use. A number of alternative methods have been suggested. The methods include genetic methods (breeding and crop cultivation practices such as fertigation, temperature and light management. A lot of research into “alternative” growth regulation was performed during the 1980-1990s, revealing several possible ways of using different climatic factors to optimize plant growth with respect to plant height. In recent years, the interest in climatic growth regulation has been resurrected, not least due to the coming phase-out of the plant growth regulator chlormequat chloride (CCC. Today, authorities in many countries are aiming towards reducing the use of agrochemicals. At the same time, there is a strong demand from consumers for products produced without chemicals. This article provides a broad overview of available methods for non-chemical growth control. It is concluded that a combination of plant breeding and management of temperature, fertigation and light management has the potential of replacing chemical growth regulators in the commercial production of ornamental pot- and bedding plants.

  6. GePb Alloy Growth Using Layer Inversion Method

    Science.gov (United States)

    Alahmad, Hakimah; Mosleh, Aboozar; Alher, Murtadha; Banihashemian, Seyedeh Fahimeh; Ghetmiri, Seyed Amir; Al-Kabi, Sattar; Du, Wei; Li, Bauhoa; Yu, Shui-Qing; Naseem, Hameed A.

    2018-04-01

    Germanium-lead films have been investigated as a new direct-bandgap group IV alloy. GePb films were deposited on Si via thermal evaporation of Ge and Pb solid sources using the layer inversion metal-induced crystallization method for comparison with the current laser-induced recrystallization method. Material characterization of the films using x-ray diffraction analysis revealed highly oriented crystallinity and Pb incorporation as high as 13.5% before and 5.2% after annealing. Transmission electron microscopy, scanning electron microscopy, and energy-dispersive x-ray mapping of the samples revealed uniform incorporation of elements and complete layer inversion. Optical characterization of the GePb films by Raman spectroscopy and photoluminescence techniques showed that annealing the samples resulted in higher crystalline quality as well as bandgap reduction. The bandgap reduction from 0.67 eV to 0.547 eV observed for the highest-quality material confirms the achievement of a direct-bandgap material.

  7. GePb Alloy Growth Using Layer Inversion Method

    Science.gov (United States)

    Alahmad, Hakimah; Mosleh, Aboozar; Alher, Murtadha; Banihashemian, Seyedeh Fahimeh; Ghetmiri, Seyed Amir; Al-Kabi, Sattar; Du, Wei; Li, Bauhoa; Yu, Shui-Qing; Naseem, Hameed A.

    2018-07-01

    Germanium-lead films have been investigated as a new direct-bandgap group IV alloy. GePb films were deposited on Si via thermal evaporation of Ge and Pb solid sources using the layer inversion metal-induced crystallization method for comparison with the current laser-induced recrystallization method. Material characterization of the films using x-ray diffraction analysis revealed highly oriented crystallinity and Pb incorporation as high as 13.5% before and 5.2% after annealing. Transmission electron microscopy, scanning electron microscopy, and energy-dispersive x-ray mapping of the samples revealed uniform incorporation of elements and complete layer inversion. Optical characterization of the GePb films by Raman spectroscopy and photoluminescence techniques showed that annealing the samples resulted in higher crystalline quality as well as bandgap reduction. The bandgap reduction from 0.67 eV to 0.547 eV observed for the highest-quality material confirms the achievement of a direct-bandgap material.

  8. New evaluation method of crack growth in SiC/SiC composites using interface elements

    International Nuclear Information System (INIS)

    Serizawa, H.; Ando, M.; Lewinsohn, C.A.; Murakawa, H.

    2000-01-01

    Crack propagation behavior in SiC/SiC composites was analyzed using a new computer simulation method that included time-dependent interface elements. The simulation method was used to describe the time-dependent crack growth in SiC/SiC composites under four-point bending of single-edge-notched beam bend-bars. Two methods were used to simulate time-dependent crack growth in SiC/SiC composites due to fiber creep. In one method, the creep property was introduced into the interface elements by the general method of finite element method (FEM) analysis. In the second method, a new technique making the best use of the potential function was used to represent crack closure tractions due to creeping fibers. The stage-II slow crack growth of a general creep deformation was simulated by both methods. Additionally, stage-III crack growth and the transition from stage-II to stage-III could be simulated by the new method. The new method has the potential to completely simulate time-dependent crack growth behavior in SiC/SiC composites due to fiber creep

  9. Study of growth of polyaniline chain by EPR method

    Energy Technology Data Exchange (ETDEWEB)

    Kulikov, A V [Inst. of Chemical Physics, Chernogolovka (Russian Federation); Kogan, Ya L [Inst. of Chemical Physics, Chernogolovka (Russian Federation); Fokeeva, L S [Inst. of Chemical Physics, Chernogolovka (Russian Federation)

    1993-03-22

    Chemical aniline polymerization has been studied by the EPR method. After a long delay a weak EPR signal I is appeared and transformed rapidly into a strong Lorentzian line. Constants of spin exchange of signals I and II with paramagnetic probes Fe(CN)[sub 6][sup 3-], Co[sup 2+] and O[sub 2], freely diffusing in solution, have been determined. Effect of ferricyanide ions and urea, a breaker of hydrogen bonds, has been measured for signals I and II. Data obtained show the formation of an array of positive charges in PANI at early stage of doping. Constants of spin exchange depend on prehistory of samples. Averaging of EPR line widths of different paramagnetic centers in polyaniline was found. (orig.)

  10. Self-assembling peptide amphiphiles and related methods for growth factor delivery

    Science.gov (United States)

    Stupp, Samuel I [Chicago, IL; Donners, Jack J. J. M.; Silva, Gabriel A [Chicago, IL; Behanna, Heather A [Chicago, IL; Anthony, Shawn G [New Stanton, PA

    2009-06-09

    Amphiphilic peptide compounds comprising one or more epitope sequences for binding interaction with one or more corresponding growth factors, micellar assemblies of such compounds and related methods of use.

  11. Growth of magnetite films by a hydrogel method

    Energy Technology Data Exchange (ETDEWEB)

    Velásquez, A.A., E-mail: avelas26@eafit.edu.edu.co [Grupo de Electromagnetismo Aplicado, Universidad EAFIT, A.A. 3300, Medellín (Colombia); Marín, C.C. [Grupo de Electromagnetismo Aplicado, Universidad EAFIT, A.A. 3300, Medellín (Colombia); Urquijo, J.P. [Grupo de Estado Sólido, Instituto de Física, Universidad de Antioquia, A.A. 1226, Medellín (Colombia)

    2017-06-15

    Magnetite (Fe{sub 3}O{sub 4}) films were grown on glass substrates by formation and condensation of complex of iron oxides in an agarose hydrogel. The obtained films were characterized by Fourier Transform Infrared Spectroscopy (FTIR), Thermogravimetric Analysis (TGA), Scanning Electron Microscopy (SEM), Room Temperature Mössbauer Spectroscopy (TMS), Vibrating Sample Magnetometry (VSM), Atomic Force Microscopy (AFM) and Voltage vs. Current measurements by the four-point method. FTIR and TGA measurements showed that some polymer chains of agarose remain linked to the surface of the magnetic particles of the films after heat treatment. SEM measurements showed that the films are composed by quasi spherical particles with sizes around 55 nm. Mössbauer spectroscopy measurements showed two sextets with broaden lines, which were assigned to magnetite with a distributed particle size, and two doublets, which were assigned to superparamagnetic phases of magnetite. For the specific dimensions of the films prepared, measurements of Voltage vs. Current showed an ohmic behavior for currents between 0 and 200 nA, with a resistance of 355 kΩ.

  12. Growth of magnetite films by a hydrogel method

    International Nuclear Information System (INIS)

    Velásquez, A.A.; Marín, C.C.; Urquijo, J.P.

    2017-01-01

    Magnetite (Fe 3 O 4 ) films were grown on glass substrates by formation and condensation of complex of iron oxides in an agarose hydrogel. The obtained films were characterized by Fourier Transform Infrared Spectroscopy (FTIR), Thermogravimetric Analysis (TGA), Scanning Electron Microscopy (SEM), Room Temperature Mössbauer Spectroscopy (TMS), Vibrating Sample Magnetometry (VSM), Atomic Force Microscopy (AFM) and Voltage vs. Current measurements by the four-point method. FTIR and TGA measurements showed that some polymer chains of agarose remain linked to the surface of the magnetic particles of the films after heat treatment. SEM measurements showed that the films are composed by quasi spherical particles with sizes around 55 nm. Mössbauer spectroscopy measurements showed two sextets with broaden lines, which were assigned to magnetite with a distributed particle size, and two doublets, which were assigned to superparamagnetic phases of magnetite. For the specific dimensions of the films prepared, measurements of Voltage vs. Current showed an ohmic behavior for currents between 0 and 200 nA, with a resistance of 355 kΩ.

  13. Influence of Plant Growth Regulators (PGRs and Planting Method on Growth and Yield in Oil Pumpkin (Cucurbita pepo var. styriaca

    Directory of Open Access Journals (Sweden)

    Shirzad SURE

    2012-05-01

    Full Text Available The effect of plant growth regulators IBA (indole butyric acid, GA3 (gibberellin and ethylene (as ethephon in two methods of planting was investigated (each method was considered as a separate experiment on morphological characters and yield of medicinal pumpkin. The experiments were carried out in a factorial trial based on completely randomized block design, with four replicates. The treatments were combined with priming and spraying with the above PGRs. The first seed priming with control (water, IBA 100 ppm, GA3 25 ppm and ethephon 200 ppm, and when seedling developed to 4 leaf stage sprayed there with control (water, IBA 100 ppm, GA3 25 ppm and ethephon 200 ppm for three times. In both planting methods, there were all of these treatments. The result showed that PGRs and planting method had significant effects on vegetative, flowering and yield characteristics including: leaf area %DM plant, number of male and female flowers per plant, number of fruit/plant, fruits fresh weight, seeds length and width, number of seed per fruit, seed yield, % seeds oil and oil yield. Hence spraying with GA3 25 ppm in four leaf stage at trellis method could be a suitable treatment for enhancing growth and yield of medicinal pumpkin.

  14. Isothermal microcalorimetry - A quantitative method to monitor Trypanosoma congolense growth and growth inhibition by trypanocidal drugs in real time.

    Science.gov (United States)

    Gysin, M; Braissant, O; Gillingwater, K; Brun, R; Mäser, P; Wenzler, T

    2018-03-16

    Trypanosoma congolense is a protozoan parasite that is transmitted by tsetse flies, causing African Animal Trypanosomiasis, also known as Nagana, in sub-Saharan Africa. Nagana is a fatal disease of livestock that causes severe economic losses. Two drugs are available, diminazene and isometamidium, yet successful treatment is jeopardized by drug resistant T. congolense. Isothermal microcalorimetry is a highly sensitive tool that can be used to study growth of the extracellular T. congolense parasites or to study parasite growth inhibition after the addition of antitrypanosomal drugs. Time of drug action and time to kill can be quantified in a simple way by real time heat flow measurements. We established a robust protocol for the microcalorimetric studies of T. congolense and developed mathematical computations in R to calculate different parameters related to growth and the kinetics of drug action. We demonstrate the feasibility and benefit of the method exemplary with the two standard drugs, diminazene aceturate and isometamidium chloride. The method and the mathematical approach can be translated to study other pathogenic or non-pathogenic cells if they are metabolically active and grow under axenic conditions. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

  15. Cellular Automaton Modeling of Dendritic Growth Using a Multi-grid Method

    International Nuclear Information System (INIS)

    Natsume, Y; Ohsasa, K

    2015-01-01

    A two-dimensional cellular automaton model with a multi-grid method was developed to simulate dendritic growth. In the present model, we used a triple-grid system for temperature, solute concentration and solid fraction fields as a new approach of the multi-grid method. In order to evaluate the validity of the present model, we carried out simulations of single dendritic growth, secondary dendrite arm growth, multi-columnar dendritic growth and multi-equiaxed dendritic growth. From the results of the grid dependency from the simulation of single dendritic growth, we confirmed that the larger grid can be used in the simulation and that the computational time can be reduced dramatically. In the simulation of secondary dendrite arm growth, the results from the present model were in good agreement with the experimental data and the simulated results from a phase-field model. Thus, the present model can quantitatively simulate dendritic growth. From the simulated results of multi-columnar and multi-equiaxed dendrites, we confirmed that the present model can perform simulations under practical solidification conditions. (paper)

  16. [A reliability growth assessment method and its application in the development of equipment in space cabin].

    Science.gov (United States)

    Chen, J D; Sun, H L

    1999-04-01

    Objective. To assess and predict reliability of an equipment dynamically by making full use of various test informations in the development of products. Method. A new reliability growth assessment method based on army material system analysis activity (AMSAA) model was developed. The method is composed of the AMSAA model and test data conversion technology. Result. The assessment and prediction results of a space-borne equipment conform to its expectations. Conclusion. It is suggested that this method should be further researched and popularized.

  17. Methods and Measures: Growth Mixture Modeling--A Method for Identifying Differences in Longitudinal Change among Unobserved Groups

    Science.gov (United States)

    Ram, Nilam; Grimm, Kevin J.

    2009-01-01

    Growth mixture modeling (GMM) is a method for identifying multiple unobserved sub-populations, describing longitudinal change within each unobserved sub-population, and examining differences in change among unobserved sub-populations. We provide a practical primer that may be useful for researchers beginning to incorporate GMM analysis into their…

  18. Moment magnitude, local magnitude and corner frequency of small earthquakes nucleating along a low angle normal fault in the Upper Tiber valley (Italy)

    Science.gov (United States)

    Munafo, I.; Malagnini, L.; Chiaraluce, L.; Valoroso, L.

    2015-12-01

    The relation between moment magnitude (MW) and local magnitude (ML) is still a debated issue (Bath, 1966, 1981; Ristau et al., 2003, 2005). Theoretical considerations and empirical observations show that, in the magnitude range between 3 and 5, MW and ML scale 1∶1. Whilst for smaller magnitudes this 1∶1 scaling breaks down (Bethmann et al. 2011). For accomplishing this task we analyzed the source parameters of about 1500 (30.000 waveforms) well-located small earthquakes occurred in the Upper Tiber Valley (Northern Apennines) in the range of -1.5≤ML≤3.8. In between these earthquakes there are 300 events repeatedly rupturing the same fault patch generally twice within a short time interval (less than 24 hours; Chiaraluce et al., 2007). We use high-resolution short period and broadband recordings acquired between 2010 and 2014 by 50 permanent seismic stations deployed to monitor the activity of a regional low angle normal fault (named Alto Tiberina fault, ATF) in the framework of The Alto Tiberina Near Fault Observatory project (TABOO; Chiaraluce et al., 2014). For this study the direct determination of MW for small earthquakes is essential but unfortunately the computation of MW for small earthquakes (MW < 3) is not a routine procedure in seismology. We apply the contributions of source, site, and crustal attenuation computed for this area in order to obtain precise spectral corrections to be used in the calculation of small earthquakes spectral plateaus. The aim of this analysis is to achieve moment magnitudes of small events through a procedure that uses our previously calibrated crustal attenuation parameters (geometrical spreading g(r), quality factor Q(f), and the residual parameter k) to correct for path effects. We determine the MW-ML relationships in two selected fault zones (on-fault and fault-hanging-wall) of the ATF by an orthogonal regression analysis providing a semi-automatic and robust procedure for moment magnitude determination within a

  19. Effectiveness of the cervical vertebral maturation method to predict postpeak circumpubertal growth of craniofacial structures.

    NARCIS (Netherlands)

    Fudalej, P.S.; Bollen, A.M.

    2010-01-01

    INTRODUCTION: Our aim was to assess effectiveness of the cervical vertebral maturation (CVM) method to predict circumpubertal craniofacial growth in the postpeak period. METHODS: The CVM stage was determined in 176 subjects (51 adolescent boys and 125 adolescent girls) on cephalograms taken at the

  20. A new method for high yield purification of type beta transforming growth factor from human platelets

    NARCIS (Netherlands)

    Eijnden-van Raaij, A.J.M. van den; Koornneef, I.; Zoelen, E.J.J. van

    1988-01-01

    A new method was developed for the purification of type beta transforming growth factor from human platelets. This method is a three-step procedure including gel filtration, weak cation exchange HPLC and reverse phase HPLC. All steps are carried out at low pH using exclusively volatile acidic buffer

  1. Cervical vertebral maturation method and mandibular growth peak: a longitudinal study of diagnostic reliability.

    Science.gov (United States)

    Perinetti, Giuseppe; Primozic, Jasmina; Sharma, Bhavna; Cioffi, Iacopo; Contardo, Luca

    2018-03-28

    The capability of the cervical vertebral maturation (CVM) method in the identification of the mandibular growth peak on an individual basis remains undetermined. The diagnostic reliability of the six-stage CVM method in the identification of the mandibular growth peak was thus investigated. From the files of the Oregon and Burlington Growth Studies (data obtained between early 1950s and middle 1970s), 50 subjects (26 females, 24 males) with at least seven annual lateral cephalograms taken from 9 to 16 years were identified. Cervical vertebral maturation was assessed according to the CVM code staging system, and mandibular growth was defined as annual increments in Co-Gn distance. A diagnostic reliability analysis was carried out to establish the capability of the circumpubertal CVM stages 2, 3, and 4 in the identification of the imminent mandibular growth peak. Variable durations of each of the CVM stages 2, 3, and 4 were seen. The overall diagnostic accuracy values for the CVM stages 2, 3, and 4 were 0.70, 0.76, and 0.77, respectively. These low values appeared to be due to false positive cases. Secular trends in conjunction with the use of a discrete staging system. In most of the Burlington Growth Study sample, the lateral head film at age 15 was missing. None of the CVM stages 2, 3, and 4 reached a satisfactorily diagnostic reliability in the identification of imminent mandibular growth peak.

  2. A Method for Upper Bounding Long Term Growth of Network Access Speed

    Directory of Open Access Journals (Sweden)

    Thomas Phillip Knudsen

    2006-06-01

    Full Text Available The development in home Internet access speed has shown an exponential development with growth rates averaging 25% per year. For resource management in network provisioning it becomes an urgent question how long such growth can continue. This paper presents a method for calculating an upper bound to visual content driven growth, proceeding from datarate requirements for a full virtual environment. Scenarios and approaches for reducing datarate requirements are considered and discussed. The presented figures for an upper bound on network access speed are discussed and perspectives on further research presented.

  3. A Method for Upper Bounding Long Term Growth of Network Access Speed

    DEFF Research Database (Denmark)

    Knudsen, Thomas Phillip; Pedersen, Jens Myrup; Madsen, Ole Brun

    2004-01-01

    The development in home Internet access speed has shown an exponential development with growth rates averaging 25% per year. For resource management in network provisioning it becomes an urgent question how long such growth can continue. This paper presents a method for calculating an upper bound...... to visual content driven growth, proceeding from datarate requirements for a full virtual environment. Scenarios and approaches for reducing datarate requirements are considered and discussed. The presented figures for an upper bound on network access speed are discussed and perspectives on further research...

  4. Researching Seeds: Films, Sanitation Methods, Microbiological Growth, Viability, and Selection for New Crops

    Science.gov (United States)

    Padgett, Niki; Smith, Trent

    2018-01-01

    A major factor in long-term human exploration of the solar system is crop growth in microgravity. Space crops can provide fresh, nutritious food to supplement diets for astronauts. Important factors impacting space plant growth and consumption are water delivery to root zone in microgravity, sanitation methods for microbiological safety, plant responses to light quality/spectrum, and identifying optimal edible plants suitable for growth on the International Space Station (ISS). Astronauts growing their own food on the ISS provides necessary data for crop production for long duration deep space missions. The seed film project can be used in Advanced Plant Habitat and Veggies that are currently being utilized on the ISS.

  5. An Eulerian-Lagrangian finite-element method for modeling crack growth in creeping materials

    International Nuclear Information System (INIS)

    Lee Hae Sung.

    1991-01-01

    This study is concerned with the development of finite-element-solution methods for analysis of quasi-static, ductile crack growth in history-dependent materials. The mixed Eulerian-Langrangian description (ELD) kinematic model is shown to have several desirable properties for modeling inelastic crack growth. Accordingly, a variational statement based on the ELD for history-dependent materials is developed, and a new moving-grid finite-element method based on the variational statement is presented. The moving-grid finite-element method based on the variational statement is presented. The moving-grid finite-element method is applied to the analysis of transient, quasi-static, mode-III crack growth in creeping materials. A generalized Petrov-Galerkin method (GPG) is developed that simultaneously stabilizes the statement to admit L 2 basis functions for the nonlinear strain field. Quasi-static, model-III crack growth in creeping materials under small-scale-yielding (SSY) conditions is considered. The GPG/ELD moving-grid finite-element formulation is used to model a transient crack-growth problem. The GPG/ELD results compare favorably with previously-published numerical results and the asymptotic solutions

  6. Homogeneous SiGe crystal growth in microgravity by the travelling liquidus-zone method

    International Nuclear Information System (INIS)

    Kinoshita, K; Arai, Y; Inatomi, Y; Sakata, K; Takayanagi, M; Yoda, S; Miyata, H; Tanaka, R; Sone, T; Yoshikawa, J; Kihara, T; Shibayama, H; Kubota, Y; Shimaoka, T; Warashina, Y

    2011-01-01

    Homogeneous SiGe crystal growth experiments will be performed on board the ISS 'Kibo' using a gradient heating furnace (GHF). A new crystal growth method invented for growing homogeneous mixed crystals named 'travelling liquidus-zone (TLZ) method' is evaluated by the growth of Si 0.5 Ge 0.5 crystals in space. We have already succeeded in growing homogeneous 2mm diameter Si 0.5 Ge 0.5 crystals on the ground but large diameter homogeneous crystals are difficult to be grown due to convection in a melt. In microgravity, larger diameter crystals can be grown with suppressing convection. Radial concentration profiles as well as axial profiles in microgravity grown crystals will be measured and will be compared with our two-dimensional TLZ growth model equation and compositional variation is analyzed. Results are beneficial for growing large diameter mixed crystals by the TLZ method on the ground. Here, we report on the principle of the TLZ method for homogeneous crystal growth, results of preparatory experiments on the ground and plan for microgravity experiments.

  7. Extraction of solubles from plant biomass for use as microbial growth stimulant and methods related thereto

    Energy Technology Data Exchange (ETDEWEB)

    Lau, Ming Woei

    2015-12-08

    A method for producing a microbial growth stimulant (MGS) from a plant biomass is described. In one embodiment, an ammonium hydroxide solution is used to extract a solution of proteins and ammonia from the biomass. Some of the proteins and ammonia are separated from the extracted solution to provide the MGS solution. The removed ammonia can be recycled and the proteins are useful as animal feeds. In one embodiment, the method comprises extracting solubles from pretreated lignocellulosic biomass with a cellulase enzyme-producing growth medium (such T. reesei) in the presence of water and an aqueous extract.

  8. Improved Growth Methods for LaBr3 Scintillation Radiation Detectors

    International Nuclear Information System (INIS)

    McGregor, Douglas S.

    2011-01-01

    The objective is to develop advanced materials for deployment as high-resolution gamma ray detectors. Both LaBr3 and CeBr3 are advanced scintillation materials, and will be studied in this research. Prototype devices, in collaboration Sandia National Laboratories, will be demonstrated along with recommendations for mass production and deployment. It is anticipated that improved methods of crystal growth will yield larger single crystals of LaBr3 for deployable room-temperature operated gamma radiation spectrometers. The growth methods will be characterized. The LaBr3 and CeBr3 scintillation crystals will be characterized for light yield, spectral resolution, and for hardness.

  9. Standard test method for measurement of creep crack growth times in metals

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2007-01-01

    1.1 This test method covers the determination of creep crack growth (CCG) in metals at elevated temperatures using pre-cracked specimens subjected to static or quasi-static loading conditions. The time (CCI), t0.2 to an initial crack extension δai = 0.2 mm from the onset of first applied force and creep crack growth rate, ˙a or da/dt is expressed in terms of the magnitude of creep crack growth relating parameters, C* or K. With C* defined as the steady state determination of the crack tip stresses derived in principal from C*(t) and Ct (1-14). The crack growth derived in this manner is identified as a material property which can be used in modeling and life assessment methods (15-25). 1.1.1 The choice of the crack growth correlating parameter C*, C*(t), Ct, or K depends on the material creep properties, geometry and size of the specimen. Two types of material behavior are generally observed during creep crack growth tests; creep-ductile (1-14) and creep-brittle (26-37). In creep ductile materials, where cr...

  10. Single-crystal growth of Group IVB and VB carbides by the floating-zone method

    International Nuclear Information System (INIS)

    Finch, C.B.; Chang, Y.K.; Abraham, M.M.

    1989-02-01

    The floating-zone method for the growth of Group IVB and VB carbides is described and reviewed. We have systematically investigated the technique and confirmed the growth of large single crystals of TiC/sub 0.95/, ZrC/sub 0.93/, ZrC/sub 0.98/, VC/sub 0.80/, NbC/sub 0.95/, TaC/sub 0.89/. Optimal growth conditions were in the 0.5-2.0 cm/h range under 8-12 atm helium. Good crystal growth results were achieved with hot-pressed starting rods of 90-95% density, using a ''double pancake'' induction coil and a 200-kHz/100- kW rf power supply. 36 refs., 5 figs., 3 tabs

  11. Evaluation of stable crack growth by using the finite element method

    International Nuclear Information System (INIS)

    Saarenheimo, A.

    1996-01-01

    In the study the analysis of stable crack growth by using the finite element method is considered. The results of numerical analyses are compared with the corresponding experimental results. The applications are reported in three separate papers enclosed at the end of the work. The first paper deals with the numerical analysis of a full scale pressure vessel test. The second and the third paper concern numerical analyses of fracture mechanical test specimens. In the literature study section of the work basic theories of fracture mechanics and common crack growth criteria are presented. The balance equations needed are written based on thermodynamical considerations. Physical interpretations of the energy release rate are briefly considered. Numerical calculation methods for determining the J-integral values are presented. The virtual crack extension method is used in the numerical examples. Also the Domain integral method and its implementation in the finite element method are described. (orig.) (70 refs.)

  12. Complete Tangent Stiffness for eXtended Finite Element Method by including crack growth parameters

    DEFF Research Database (Denmark)

    Mougaard, J.F.; Poulsen, P.N.; Nielsen, L.O.

    2013-01-01

    the crack geometry parameters, such as the crack length and the crack direction directly in the virtual work formulation. For efficiency, it is essential to obtain a complete tangent stiffness. A new method in this work is presented to include an incremental form the crack growth parameters on equal terms......The eXtended Finite Element Method (XFEM) is a useful tool for modeling the growth of discrete cracks in structures made of concrete and other quasi‐brittle and brittle materials. However, in a standard application of XFEM, the tangent stiffness is not complete. This is a result of not including...... with the degrees of freedom in the FEM‐equations. The complete tangential stiffness matrix is based on the virtual work together with the constitutive conditions at the crack tip. Introducing the crack growth parameters as direct unknowns, both equilibrium equations and the crack tip criterion can be handled...

  13. Evaluation of Irrigation Methods for Highbush Blueberry. I. Growth and Water Requirements of Young Plants

    Science.gov (United States)

    A study was conducted in a new field of northern highbush blueberry (Vaccinium corymbosum L. 'Elliott') to determine the effects of different irrigation methods on growth and water requirements of uncropped plants during the first 2 years after planting. The plants were grown on mulched, raised beds...

  14. In ovo method for evaluating the effect of nutritional therapies on tumor development, growth and vascularization

    OpenAIRE

    Dupertuis, Yves M.; Delie, Florence; Cohen, Marie; Pichard, Claude

    2015-01-01

    In the state of the art evaluation of nutritional therapy on tumor development, growth and vascularization requires tedious and expensive in vivo assays in which a significant number of animals undergo invasive treatments. Therefore, new alternative methods to avoid animal suffering and sacrifice are welcome. This review presents a rapid and low-cost method of experimental radio/chemotherapy in tumor xenografted chicken chorioallantoic membrane (CAM), which may contribute to implement the 3R ...

  15. Non-Contact Plant Growth Measurement Method and System Based on Ubiquitous Sensor Network Technologies

    Directory of Open Access Journals (Sweden)

    Intae Ryoo

    2011-04-01

    Full Text Available This paper proposes a non-contact plant growth measurement system using infrared sensors based on the ubiquitous sensor network (USN technology. The proposed system measures plant growth parameters such as the stem radius of plants using real-time non-contact methods, and generates diameter, cross-sectional area and thickening form of plant stems using this measured data. Non-contact sensors have been used not to cause any damage to plants during measurement of the growth parameters. Once the growth parameters are measured, they are transmitted to a remote server using the sensor network technology and analyzed in the application program server. The analyzed data are then provided for administrators and a group of interested users. The proposed plant growth measurement system has been designed and implemented using fixed-type and rotary-type infrared sensor based measurement methods and devices. Finally, the system performance is compared and verified with the measurement data that have been obtained by practical field experiments.

  16. Comparison of growth methods and biological activities of brazilian marine Streptomyces

    Directory of Open Access Journals (Sweden)

    A. C. Granato

    2013-03-01

    Full Text Available The present work describes the study of the growth and the cytotoxic and antitumor activities of the extracts of the marine microorganisms Streptomyces acrymicini and Streptomyces cebimarensis, the latter a new strain. Both microorganisms were collected from coastal marine sediments of the north coast of São Paulo state. Growth was performed in a shaker and in a bioreactor using Gym medium and the broths of both microorganisms were extracted with ethyl acetate and n-butanol. Three extracts, two organic and one aqueous, from each microorganism were obtained and tested for cytotoxic and antitumor activity using the SF-295 (Central Nervous System, HCT-8 (Colon cell lines, and the MTT (3-(4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide method. The growth methods were compared and show that, although the shaker presented reasonable results, the bioreactor represents the best choice for growth of these microorganisms. The biological activity of the different extracts was evaluated and it was demonstrated that the growth methodology may influence the secondary metabolite production and the biological activity.

  17. An efficient computational method for global sensitivity analysis and its application to tree growth modelling

    International Nuclear Information System (INIS)

    Wu, Qiong-Li; Cournède, Paul-Henry; Mathieu, Amélie

    2012-01-01

    Global sensitivity analysis has a key role to play in the design and parameterisation of functional–structural plant growth models which combine the description of plant structural development (organogenesis and geometry) and functional growth (biomass accumulation and allocation). We are particularly interested in this study in Sobol's method which decomposes the variance of the output of interest into terms due to individual parameters but also to interactions between parameters. Such information is crucial for systems with potentially high levels of non-linearity and interactions between processes, like plant growth. However, the computation of Sobol's indices relies on Monte Carlo sampling and re-sampling, whose costs can be very high, especially when model evaluation is also expensive, as for tree models. In this paper, we thus propose a new method to compute Sobol's indices inspired by Homma–Saltelli, which improves slightly their use of model evaluations, and then derive for this generic type of computational methods an estimator of the error estimation of sensitivity indices with respect to the sampling size. It allows the detailed control of the balance between accuracy and computing time. Numerical tests on a simple non-linear model are convincing and the method is finally applied to a functional–structural model of tree growth, GreenLab, whose particularity is the strong level of interaction between plant functioning and organogenesis. - Highlights: ► We study global sensitivity analysis in the context of functional–structural plant modelling. ► A new estimator based on Homma–Saltelli method is proposed to compute Sobol indices, based on a more balanced re-sampling strategy. ► The estimation accuracy of sensitivity indices for a class of Sobol's estimators can be controlled by error analysis. ► The proposed algorithm is implemented efficiently to compute Sobol indices for a complex tree growth model.

  18. Growth of ruby crystals by the heat exchanger method, phase 1: NSF small business innovation research

    Science.gov (United States)

    Schmid, F.; Khattak, C. P.

    1980-03-01

    Conditions for the growth of large, uniformly doped laser crystals by the heat exchanger method are explored. Determination of the melt point, selection of crucible material and establishment of furnace operating parameters are discussed. The melt point of ruby was found to be 2040 plus or minus 10 C. Molybdenum crucibles can be used to contain ruby in vacuum as well as under argon atmospheres at desired superheat temperatures over extended periods required for crystal growth. Thermodynamic analysis was conducted and vapor pressures of volatile species calculated. Experimentally, volatilization of chromium oxides was suppressed by using welded covers on crucibles and operating under an argon pressure in the furnace.

  19. A new diatom growth inhibition assay using the XTT colorimetric method.

    Science.gov (United States)

    Jiang, Weina; Akagi, Takuya; Suzuki, Hidekazu; Takimoto, Ayaka; Nagai, Hiroshi

    2016-01-01

    Marine biofouling, which leads to significant operational stress and economic damage on marine infrastructures, is a major problem in marine related industries. Currently, the most common way to avoid marine biofouling involves the use of biocidal products in surface coatings. However, the need for environmentally friendly antibiofouling compounds has increased rapidly with the recent global prohibition of harmful antifoulants, such as tributyltin (TBT). In particular, periphytic diatoms have been shown to contribute significantly to biofilms, which play an important role in biofouling. Therefore, inhibiting the proliferation of fouling diatoms is a very important step in the prevention of marine biofouling. In this study, we developed a new, rapid, accurate, and convenient growth inhibition assay using the XTT colorimetric method to prevent the growth of the fouling periphytic diatom, Nitzschia amabilis Hidek. Suzuki (replaced synonym, Nitzschia laevis Hustedt). The feasibility of this method was verified by determining the growth inhibition activities of two standard photosynthetic inhibitors, DCMU and CuSO4. However, neither inhibitor had any cytotoxic activities at the range of concentrations tested. Moreover, this method was applied by screening and purification of herbicidic but non-cytotoxic compounds from cyanobacteria extracts. Our results demonstrate the utility of this newly established growth inhibition assay for the identification of marine anti-biofouling compounds. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. Microwave-assisted Facile and Ultrafast Growth of ZnO Nanostructures and Proposition of Alternative Microwave-assisted Methods to Address Growth Stoppage

    Science.gov (United States)

    Rana, Abu Ul Hassan Sarwar; Kang, Mingi; Kim, Hyun-Seok

    2016-04-01

    The time constraint in the growth of ZnO nanostructures when using a hydrothermal method is of paramount importance in contemporary research, where a long fabrication time rots the very essence of the research on ZnO nanostructures. In this study, we present the facile and ultrafast growth of ZnO nanostructures in a domestic microwave oven within a pressurized environment in just a few minutes. This method is preferred for the conventional solution-based method because of the ultrafast supersaturation of zinc salts and the fabrication of high-quality nanostructures. The study of the effect of seed layer density, growth time, and the solution’s molar concentration on the morphology, alignment, density, and aspect ratio of ZnO nanorods (ZNRs) is explored. It is found in a microwave-assisted direct growth method that ~5 mins is the optimum time beyond which homogeneous nucleation supersedes heterogeneous nucleation, which results in the growth stoppage of ZNRs. To deal with this issue, we propound different methods such as microwave-assisted solution-replacement, preheating, and PEI-based growth methods, where growth stoppage is addressed and ZNRs with a high aspect ratio can be grown. Furthermore, high-quality ZnO nanoflowers and ZnO nanowalls are fabricated via ammonium hydroxide treatment in a very short time.

  1. Taguchi method for partial differential equations with application in tumor growth.

    Science.gov (United States)

    Ilea, M; Turnea, M; Rotariu, M; Arotăriţei, D; Popescu, Marilena

    2014-01-01

    The growth of tumors is a highly complex process. To describe this process, mathematical models are needed. A variety of partial differential mathematical models for tumor growth have been developed and studied. Most of those models are based on the reaction-diffusion equations and mass conservation law. A variety of modeling strategies have been developed, each focusing on tumor growth. Systems of time-dependent partial differential equations occur in many branches of applied mathematics. The vast majority of mathematical models in tumor growth are formulated in terms of partial differential equations. We propose a mathematical model for the interactions between these three cancer cell populations. The Taguchi methods are widely used by quality engineering scientists to compare the effects of multiple variables, together with their interactions, with a simple and manageable experimental design. In Taguchi's design of experiments, variation is more interesting to study than the average. First, Taguchi methods are utilized to search for the significant factors and the optimal level combination of parameters. Except the three parameters levels, other factors levels other factors levels would not be considered. Second, cutting parameters namely, cutting speed, depth of cut, and feed rate are designed using the Taguchi method. Finally, the adequacy of the developed mathematical model is proved by ANOVA. According to the results of ANOVA, since the percentage contribution of the combined error is as small. Many mathematical models can be quantitatively characterized by partial differential equations. The use of MATLAB and Taguchi method in this article illustrates the important role of informatics in research in mathematical modeling. The study of tumor growth cells is an exciting and important topic in cancer research and will profit considerably from theoretical input. Interpret these results to be a permanent collaboration between math's and medical oncologists.

  2. Growth mechanisms and morphology of NaCl monocrystals obtained by the Czochralski method

    International Nuclear Information System (INIS)

    Goujon, Gilles G.

    1969-01-01

    In its first part, this research thesis describes the various aspects of the theory of crystal growth in melt bath by drawing with growth being limited either by heat transfer phenomena or by mechanisms of molecule transport through the interface. The second part addresses the quality of the obtained monocrystals (dislocations, dislocation density) while discussing the impact of external growth parameters (germ choice and orientation, drawing speed, rotating speed, atmosphere, impurities, crystal diameter). Then, the author presents an experimental study (equipment, experimental conditions) and discusses its results (influence of temperature on crystal geometry, morphology of side surface, study of crystal plane faces by chemical attack). The next part proposes an interpretation of the morphology change of a crystal drawn by the Czochralski method

  3. Graphene growth on Ge(100)/Si(100) substrates by CVD method.

    Science.gov (United States)

    Pasternak, Iwona; Wesolowski, Marek; Jozwik, Iwona; Lukosius, Mindaugas; Lupina, Grzegorz; Dabrowski, Pawel; Baranowski, Jacek M; Strupinski, Wlodek

    2016-02-22

    The successful integration of graphene into microelectronic devices is strongly dependent on the availability of direct deposition processes, which can provide uniform, large area and high quality graphene on nonmetallic substrates. As of today the dominant technology is based on Si and obtaining graphene with Si is treated as the most advantageous solution. However, the formation of carbide during the growth process makes manufacturing graphene on Si wafers extremely challenging. To overcome these difficulties and reach the set goals, we proposed growth of high quality graphene layers by the CVD method on Ge(100)/Si(100) wafers. In addition, a stochastic model was applied in order to describe the graphene growth process on the Ge(100)/Si(100) substrate and to determine the direction of further processes. As a result, high quality graphene was grown, which was proved by Raman spectroscopy results, showing uniform monolayer films with FWHM of the 2D band of 32 cm(-1).

  4. A simple method to tune graphene growth between monolayer and bilayer

    Directory of Open Access Journals (Sweden)

    Xiaozhi Xu

    2016-02-01

    Full Text Available Selective growth of either monolayer or bilayer graphene is of great importance. We developed a method to readily tune large area graphene growth from complete monolayer to complete bilayer. In an ambient pressure chemical vapor deposition process, we used the sample temperature at which to start the H2 flow as the control parameter and realized the change from monolayer to bilayer growth of graphene on Cu foil. When the H2 starting temperature was above 700°C, continuous monolayer graphene films were obtained. When the H2 starting temperature was below 350°C, continuous bilayer films were obtained. Detailed characterization of the samples treated under various conditions revealed that heating without the H2 flow caused Cu oxidation. The more the Cu substrate oxidized, the less graphene bilayer could form.

  5. Development of a model for on-line control of crystal growth by the AHP method

    Science.gov (United States)

    Gonik, M. A.; Lomokhova, A. V.; Gonik, M. M.; Kuliev, A. T.; Smirnov, A. D.

    2007-05-01

    The possibility to apply a simplified 2D model for heat transfer calculations in crystal growth by the axial heat close to phase interface (AHP) method is discussed in this paper. A comparison with global heat transfer calculations with the CGSim software was performed to confirm the accuracy of this model. The simplified model was shown to provide adequate results for the shape of the melt-crystal interface and temperature field in an opaque (Ge) and a transparent crystal (CsI:Tl). The model proposed is used for identification of the growth setup as a control object, for synthesis of a digital controller (PID controller at the present stage) and, finally, in on-line simulations of crystal growth control.

  6. Verification of annual growth rings in Egyptian trees by C-14 method

    International Nuclear Information System (INIS)

    Belacy, N.; Abou El-Nour, F.; Jacoby, G.C.

    1990-01-01

    Annual growth rings in trees were thought to be due to sharp seasonal variations in the precipitation rates during the year. Accordingly temperature zone trees such as Egyptian trees were supposed to be away from this phenomenon. The temperature zones which are meant here are those of no sharp seasonal variations in the precipitation rates. The present study applied carbon-14 dating to prove that the growth rings in some Egyptian trees are annual. The method was based on the tropospheric measurements of C-14 during the period 1954-1981. C-14 exhibited a sharp peak resulting from the ever greater series of nuclear tests during 1963-1965. The presence of this peak for Egyptian trees proved that they form annual growth rings. (orig.) [de

  7. The performance studies of DKDP crystals grown by a rapid horizontal growth method

    Science.gov (United States)

    Xie, Xiaoyi; Qi, Hongji; Wang, Bin; Wang, Hu; Chen, Duanyang; Shao, Jianda

    2018-04-01

    A deuterated potassium dihydrogen phosphate (DKDP) crystal with about 70% deuterium level was grown by a rapid horizontal growth method with independent design equipment, which includes a continuous filtration system. The cooling program during crystal growth was designed according to a self-developed software to catch the size of growing crystal in real time. The crystal structure, optical performance and laser induced damage threshold (LIDT) of this DKDP crystal were investigated in this paper. The deuterium concentration of the crystal was confirmed by the neutron diffraction technique, which was effective and available in determining a complete range of deuteration level. The dielectric property was measured to evaluate the perfection of the lattice. The transmittance and LIDT were carried out further to evaluate the optical and functional properties of this DKDP crystal grown in the rapid horizontal growth technique. All of the detailed characterization for DKDP figured out that the 70% deuterated KDP crystal grown in this way had relatively good qualities.

  8. A high precision extrapolation method in multiphase-field model for simulating dendrite growth

    Science.gov (United States)

    Yang, Cong; Xu, Qingyan; Liu, Baicheng

    2018-05-01

    The phase-field method coupling with thermodynamic data has become a trend for predicting the microstructure formation in technical alloys. Nevertheless, the frequent access to thermodynamic database and calculation of local equilibrium conditions can be time intensive. The extrapolation methods, which are derived based on Taylor expansion, can provide approximation results with a high computational efficiency, and have been proven successful in applications. This paper presents a high precision second order extrapolation method for calculating the driving force in phase transformation. To obtain the phase compositions, different methods in solving the quasi-equilibrium condition are tested, and the M-slope approach is chosen for its best accuracy. The developed second order extrapolation method along with the M-slope approach and the first order extrapolation method are applied to simulate dendrite growth in a Ni-Al-Cr ternary alloy. The results of the extrapolation methods are compared with the exact solution with respect to the composition profile and dendrite tip position, which demonstrate the high precision and efficiency of the newly developed algorithm. To accelerate the phase-field and extrapolation computation, the graphic processing unit (GPU) based parallel computing scheme is developed. The application to large-scale simulation of multi-dendrite growth in an isothermal cross-section has demonstrated the ability of the developed GPU-accelerated second order extrapolation approach for multiphase-field model.

  9. Numerical investigation of flows in Czochralski crystal growth by an axisymmetric lattice Boltzmann method

    Science.gov (United States)

    Peng, Y.; Shu, C.; Chew, Y. T.; Qiu, J.

    2003-03-01

    An alternative new method called lattice Boltzmann method (LBM) is applied in this work to simulate the flows in Czochralski crystal growth, which is one of the widely used prototypical systems for melt-crystal growth. The standard LBM can only be used in Cartesian coordinate system and we extend it to be applicable to this axisymmetric thermal flow problem, avoiding the use of three-dimensional LBM on Cartesian coordinate system. The extension is based on the following idea. By inserting position and time dependent source terms into the evolution equation of standard LBM, the continuity and NS equations on the cylindrical coordinate system [1] can be recovered. Our extension is validated by its application to the benchmark problem suggested by Wheeler [2].

  10. Numerical investigation of flows in Czochralski crystal growth by an axisymmetric lattice Boltzmann method

    International Nuclear Information System (INIS)

    Peng, Y.; Shu, C.; Chew, Y.T.; Qiu, J.

    2003-01-01

    An alternative new method called lattice Boltzmann method (LBM) is applied in this work to simulate the flows in Czochralski crystal growth, which is one of the widely used prototypical systems for melt-crystal growth. The standard LBM can only be used in Cartesian coordinate system and we extend it to be applicable to this axisymmetric thermal flow problem, avoiding the use of three-dimensional LBM on Cartesian coordinate system. The extension is based on the following idea. By inserting position and time dependent source terms into the evolution equation of standard LBM, the continuity and NS equations on the cylindrical coordinate system can be recovered. Our extension is validated by its application to the benchmark problem suggested by Wheeler

  11. Numerical investigation of flows in Czochralski crystal growth by an axisymmetric lattice Boltzmann method

    CERN Document Server

    Peng, Y; Chew, Y T; Qiu, J

    2003-01-01

    An alternative new method called lattice Boltzmann method (LBM) is applied in this work to simulate the flows in Czochralski crystal growth, which is one of the widely used prototypical systems for melt-crystal growth. The standard LBM can only be used in Cartesian coordinate system and we extend it to be applicable to this axisymmetric thermal flow problem, avoiding the use of three-dimensional LBM on Cartesian coordinate system. The extension is based on the following idea. By inserting position and time dependent source terms into the evolution equation of standard LBM, the continuity and NS equations on the cylindrical coordinate system can be recovered. Our extension is validated by its application to the benchmark problem suggested by Wheeler .

  12. Influence of Te and Se doping on ZnO films growth by SILAR method

    Science.gov (United States)

    Güney, Harun; Duman, Ćaǧlar

    2016-04-01

    The AIP Successive ionic layer adsorption and reaction (SILAR) is an economic and simple method to growth thin films. In this study, SILAR method is used to growth Selenium (Se) and Tellurium (Te) doped zinc oxide (ZnO) thin films with different doping rates. For characterization of the films X-ray diffraction (XRD), absorbance and scanning electron microscopy (SEM) are used. XRD results are showed well-defined strongly (002) oriented crystal structure for all samples. Also, absorbance measurements show, Te and Se concentration are proportional and inversely proportional with band gap energy, respectively. SEM measurements show that the surface morphology and thickness of the material varied with Se and/or Te and varying concentrations.

  13. Influence of Te and Se doping on ZnO films growth by SILAR method

    International Nuclear Information System (INIS)

    Güney, Harun; Duman, Çağlar

    2016-01-01

    The AIP Successive ionic layer adsorption and reaction (SILAR) is an economic and simple method to growth thin films. In this study, SILAR method is used to growth Selenium (Se) and Tellurium (Te) doped zinc oxide (ZnO) thin films with different doping rates. For characterization of the films X-ray diffraction (XRD), absorbance and scanning electron microscopy (SEM) are used. XRD results are showed well-defined strongly (002) oriented crystal structure for all samples. Also, absorbance measurements show, Te and Se concentration are proportional and inversely proportional with band gap energy, respectively. SEM measurements show that the surface morphology and thickness of the material varied with Se and/or Te and varying concentrations.

  14. Influence of Te and Se doping on ZnO films growth by SILAR method

    Energy Technology Data Exchange (ETDEWEB)

    Güney, Harun, E-mail: harunguney25@hotmail.com [Department of Electric and Energy, Vocation High School, Ağrı İbrahim Çeçen University (Turkey); Duman, Çağlar, E-mail: caglarduman@erzurum.edu.tr [Department of Electrical and Electronic Engineering, Faculty of Engineering, Erzurum Technical University (Turkey)

    2016-04-18

    The AIP Successive ionic layer adsorption and reaction (SILAR) is an economic and simple method to growth thin films. In this study, SILAR method is used to growth Selenium (Se) and Tellurium (Te) doped zinc oxide (ZnO) thin films with different doping rates. For characterization of the films X-ray diffraction (XRD), absorbance and scanning electron microscopy (SEM) are used. XRD results are showed well-defined strongly (002) oriented crystal structure for all samples. Also, absorbance measurements show, Te and Se concentration are proportional and inversely proportional with band gap energy, respectively. SEM measurements show that the surface morphology and thickness of the material varied with Se and/or Te and varying concentrations.

  15. Methods for growth of relatively large step-free SiC crystal surfaces

    Science.gov (United States)

    Neudeck, Philip G. (Inventor); Powell, J. Anthony (Inventor)

    2002-01-01

    A method for growing arrays of large-area device-size films of step-free (i.e., atomically flat) SiC surfaces for semiconductor electronic device applications is disclosed. This method utilizes a lateral growth process that better overcomes the effect of extended defects in the seed crystal substrate that limited the obtainable step-free area achievable by prior art processes. The step-free SiC surface is particularly suited for the heteroepitaxial growth of 3C (cubic) SiC, AlN, and GaN films used for the fabrication of both surface-sensitive devices (i.e., surface channel field effect transistors such as HEMT's and MOSFET's) as well as high-electric field devices (pn diodes and other solid-state power switching devices) that are sensitive to extended crystal defects.

  16. Prediction system of hydroponic plant growth and development using algorithm Fuzzy Mamdani method

    Science.gov (United States)

    Sudana, I. Made; Purnawirawan, Okta; Arief, Ulfa Mediaty

    2017-03-01

    Hydroponics is a method of farming without soil. One of the Hydroponic plants is Watercress (Nasturtium Officinale). The development and growth process of hydroponic Watercress was influenced by levels of nutrients, acidity and temperature. The independent variables can be used as input variable system to predict the value level of plants growth and development. The prediction system is using Fuzzy Algorithm Mamdani method. This system was built to implement the function of Fuzzy Inference System (Fuzzy Inference System/FIS) as a part of the Fuzzy Logic Toolbox (FLT) by using MATLAB R2007b. FIS is a computing system that works on the principle of fuzzy reasoning which is similar to humans' reasoning. Basically FIS consists of four units which are fuzzification unit, fuzzy logic reasoning unit, base knowledge unit and defuzzification unit. In addition to know the effect of independent variables on the plants growth and development that can be visualized with the function diagram of FIS output surface that is shaped three-dimensional, and statistical tests based on the data from the prediction system using multiple linear regression method, which includes multiple linear regression analysis, T test, F test, the coefficient of determination and donations predictor that are calculated using SPSS (Statistical Product and Service Solutions) software applications.

  17. Effects of different CMV-heat-inactivation-methods on growth factors in human breast milk.

    Science.gov (United States)

    Goelz, Rangmar; Hihn, Eva; Hamprecht, Klaus; Dietz, Klaus; Jahn, Gerhard; Poets, Christian; Elmlinger, Martin

    2009-04-01

    Preterm infants can inoculate virulent cytomegalovirus (CMV) through their mothers' raw breast milk. Complete virus inactivation is achieved only by heat treatment, but the effect on growth factors has never been assessed systematically. Insulin-like-growth-factor-1-, IGF-2-, insulin-like-growth-factor-binding-protein-2-, and IGFBP-3-concentrations were measured, before and after heating, in 51 breast-milk-samples from 28 mothers, and epidermal-growth-factor-concentrations in a subgroup of 35 samples from 22 mothers. Two heating methods were applied: Short-term (5 s) pasteurisation at 62, 65, and 72 degrees C, and long-term Holder-Pasteurisation (30 min) at 63 degrees C. IGF-1, IGF-2, IGFBP-2, and IGFBP-3 were measured by RIA, and EGF by ELISA. Heating for 30 min decreased significantly IGF-1 by 39.4%, IGF-2 by 9.9%, IGFBP-2 by 19.1%, and IGFBP-3 by 7.0%. In contrast, IGF-1, IGF-2, IGFBP-2, and IGFBP-3 were not altered significantly when using a short heating duration of 5 s, irrespective of the level of temperature, except for IGF-2 at 62 degrees C for 5 s (p = 0.041) and IGFBP-2 at 72 degrees C for 5 s (p = 0.025). Neither long- nor short-time heating methods changed the concentration of EGF. Only short heating methods (5 s, 62-72 degrees C) can preserve, almost completely, the concentrations of IGFs in human milk, whereas Holder-Pasteurization does not.

  18. High Quality, Low Cost Bulk Gallium Nitride Substrates Grown by the Electrochemical Solution Growth Method

    Energy Technology Data Exchange (ETDEWEB)

    Seacrist, Michael [SunEdison Inc., St. Peters, MO (United States)

    2017-08-15

    The objective of this project was to develop the Electrochemical Solution Growth (ESG) method conceived / patented at Sandia National Laboratory into a commercially viable bulk gallium nitride (GaN) growth process that can be scaled to low cost, high quality, and large area GaN wafer substrate manufacturing. The goal was to advance the ESG growth technology by demonstrating rotating seed growth at the lab scale and then transitioning process to prototype commercial system, while validating the GaN material and electronic / optical device quality. The desired outcome of the project is a prototype commercial process for US-based manufacturing of high quality, large area, and lower cost GaN substrates that can drive widespread deployment of energy efficient GaN-based power electronic and optical devices. In year 1 of the project (Sept 2012 – Dec 2013) the overall objective was to demonstrate crystalline GaN growth > 100um on a GaN seed crystal. The development plan included tasks to demonstrate and implement a method for purifying reagent grade salts, develop the reactor 1 process for rotating seed Electrochemical Solution Growth (ESG) of GaN, grow and characterize ESG GaN films, develop a fluid flow and reaction chemistry model for GaN film growth, and design / build an improved growth reactor capable of scaling to 50mm seed diameter. The first year’s project objectives were met in some task areas including salt purification, film characterization, modeling, and reactor 2 design / fabrication. However, the key project objective of the growth of a crystalline GaN film on the seed template was not achieved. Amorphous film growth on the order of a few tenths of a micron has been detected with a film composition including Ga and N, plus several other impurities originating from the process solution and hardware. The presence of these impurities, particularly the oxygen, has inhibited the demonstration of crystalline GaN film growth on the seed template. However, the

  19. METHODS FOR OVERCOMING SEED DORMANCY AND THE INITIAL GROWTH OF Ziziphus joazeiro Mart. IN DIFFERENT SOILS

    Directory of Open Access Journals (Sweden)

    JOSENARA DAIANE DE SOUZA COSTA

    2016-01-01

    Full Text Available Considering the potential and importance of biodiversity of the Caatinga biome, studies on endemic species are relevant to conservation of its natural resources. The objectives of this work was to evaluate seed viability and physical methods for overcoming seed dormancy in juazeiro (Ziziphus joazeiro Mart. and assess the influence of different types of soil on the initial growth of juazeiro plants. The experiments were conducted in three stages. In the first stage, the viability of seeds from different lots was evaluated using the tetrazolium test. The second stage was conducted in a plant nursery, evaluating the application of physical processes (scarification with sandpaper and hammer in overcoming seed dormancy, and the initial growth of the plants. In the third step, the chlorophyll a and b contents, gas exchange and dry matter accumulation were evaluated in young juazeiro plants in three types of soil (Oxisol, Entisol and Vertisol. The results indicate that the viability of juazeiro seeds is greatly influenced by differences between the progenitor plants and by storage conditions, which enable a longevity of two years when stored at 22°C and 16% of relative humidity. The scarification methods with sandpaper and hammer are not efficient to reduce the time and uniform seed germination. The juazeiro plants have high growth potential in different edaphic environments, adapting well to soils of different textures and chemical compositions.

  20. Simulating the growth process of aromatic polyamide layer by monomer concentration controlling method

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Yan [Vontron Technology Co., Ltd., Guiyang 550018, Guizhou (China); Liang, Songmiao, E-mail: liangsongmiao@vontron.com.cn [Vontron Technology Co., Ltd., Guiyang 550018, Guizhou (China); Wu, Zongce; Cai, Zhiqi [Vontron Technology Co., Ltd., Guiyang 550018, Guizhou (China); Zhao, Ning [National Laboratory of Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences (ICCAS), Beijing 100190 (China)

    2014-09-30

    Highlights: • A concentration controlling method to simulate the growth process of polyamide layer was developed. • The surface structure features and properties of polyamide layer at its different growth stages were systematically investigated. • Structure transition from spherical aggregator to leaf-like to typical ridge-and-valley was observed. • The performance of RO membrane is closely related to the structure of polyamide. - Abstract: With the wide distribution and gradual increase of TMC concentration (C{sub TMC}) from 1 × 10{sup −4} wt% to 2.5 × 10{sup −1} wt%, the main purpose of this work is to simulate the surface structure and properties of polyamide layer of reverse osmosis membranes at its different growth stage. The surface structure and properties of the resulted membranes were then characterized by atomic force microscopy (AFM), scanning electron microscope (SEM), attenuated total reflectance infrared (ATR-IR) spectroscopy, drop shape analysis system and electrokinetic analyzer. The structure growth of polyamide layer underwent in turn three different stages including spherical aggregator, leaf-like and typical ridge-valley structure. Spherical aggregator is the intrinsic structure in the inner layer of polyamide while leaf-like structure is transitional on the outmost polyamide layer. Furthermore, to clarify the effect of the structure change on the properties of polyamide layer, contact angle and zeta potential in the surface of polyamide layer were studied. Hydrophilic surface of polyamide layer is accessible at higher TMC concentration because of the presence of negative charged groups. Performances of the membranes were further measured with an emphasis on studying its structure–performance relationship during the growth process of polyamide layer.

  1. The study of thin film growth by using Monte Carlo method

    International Nuclear Information System (INIS)

    Tandogan, M.; Aktas, S.

    2010-01-01

    Thin film growth was studied by using Monte Carlo simulation method. Three basic models were used in this study. Model A, the gas particles used for the formation of film were under no external effects until they stick on the surface or to another particle which already stickled on the surface to form the film. Model B, gases were drifted towards the surface by an external agent. Model C, where the gas particles in the closed container were always distributed uniformly throughout the container while they are in gas state. The simulations revealed the fact that for an ideal thin film growth Model C gave the best result to prepare a thin film while a thicker but a better quality could be obtained by Model B.

  2. On some descriptive and predictive methods for the dynamics of cancer growth

    Directory of Open Access Journals (Sweden)

    Iulian T. Vlad

    2015-09-01

    Full Text Available Cancer is a widely spread disease that affects a large proportion of the human population, and many research teams are developing algorithms to help medics to understand this disease. In particular, tumor growth has been studied from different viewpoints and several mathematical models have been proposed. In this paper, we review a set of comprehensive and modern tools that are useful for prediction of cancer growth in space and time. We comment on three alternative approaches. We first consider spatio-temporal stochastic processes within a Bayesian framework to model spatial heterogeneity, temporal dependence and spatio-temporal interactions amongst the pixels, providing a general modeling framework for such dynamics. We then consider predictions based on geometric properties of plane curves and vectors, and propose two methods of geometric prediction. Finally we focus on functional data analysis to statistically compare tumor contour evolutions. We also analyze real data on brain tumor.

  3. A simple method for analysing the effects of algae on the growth of Lemna and preventing algal growth in duckweed bioassays

    NARCIS (Netherlands)

    Szabo, S.; Roijackers, R.M.M.; Scheffer, M.

    2003-01-01

    A simple novel method for indoor culture experiments with small floating water plants, such as Lemnaceae, is described. Experiments demonstrate that the method allows for longer lasting culture experiments with Lemna, avoiding algal growth and self-shading of fronds by overcrowding. This is achieved

  4. Responses of growth of lady's fingers (Abelmoschus esculentus L.) to different treatments methods of dairy wastewater.

    Science.gov (United States)

    Al-Dulaimi, Rana Ibrahim; Ismail, Norli; Ibrahim, Mahamad H

    2014-01-01

    Water is one of the most important precious resources found on the earth, and are most often affected by anthropogenic activities and by industry. Pollution caused by human beings and industries is a serious concern throughout the world. Population growth, massive urbanization, rapid rate of industrialization and modern techniques in agriculture have accelerated water pollution and led to the gradual deterioration of its quality. A large quantity of waste water disposed of at sea or on land has caused environmental problems which have led to environmental pollution, economic losses and chemical risks caused by the wastewater, and its impact on agriculture. However, waste water which contain nutrients and organic matter has possible advantages for agricultural purposes. Therefore, the presented study was undertaken to assess the impact of Dairy Effluent (treated and untreated waste water) on seed germination, seedling growth, dry matter production and the biochemical parameters of lady's fingers (Abelmoschus esculentus L.). A field experiment in a green house was conducted to use raw and treated dairy wastewater for watering lady's fingers (Abelmoschus esculentus L.). The plants were watered using (WW) raw dairy wastewater, (T1) chemicals treatment, (T2) physical treatment, (T3) dilution method treatment and tap water (TW) in pot experiments. Ten plants of each treatment /3 replicate were randomly selected and labelled for the collection of data. The data was collected sequentially, starting with chlorophyll content pre-harvest, vegetative qualities (shoot, root and seedling length) and dry matter quality (shoot and root dry matter) pos-tharvest. The effect was seen on the germination seed and growth of the plant. The results showed inhibitory effect from dairy effluent (WW) on seed germination and plant growth. Treatment with chemicals showed statistically significant differences with other treatments. Chemical treatment (TC2) at 20 mg/L Al2(SO4)3 and pH 6

  5. In ovo method for evaluating the effect of nutritional therapies on tumor development, growth and vascularization

    Directory of Open Access Journals (Sweden)

    Yves M. Dupertuis

    2015-10-01

    Full Text Available In the state of the art evaluation of nutritional therapy on tumor development, growth and vascularization requires tedious and expensive in vivo assays in which a significant number of animals undergo invasive treatments. Therefore, new alternative methods to avoid animal suffering and sacrifice are welcome. This review presents a rapid and low-cost method of experimental radio/chemotherapy in tumor xenografted chicken chorioallantoic membrane (CAM, which may contribute to implement the 3R principle (Reduce, Refine, Replace. Advantages and limitations of the CAM as an experimental model in cancer research are discussed. Improving the CAM model by using tumor spheroid grafting and positron emission and computed tomography imaging would help to overcome the drawbacks of poor tumor grafting efficiency and restrained 2-D tumor growth measurement to the CAM surface. Such a simple, reliable, reproducible and quantitative method for obtaining dose–response analysis and estimating treatment schedule (i.e. type, route, dose and timing would provide an alternative to the time-consuming and expensive evaluation step in animals before initiating clinical trials.

  6. Optimization of the purification methods for recovery of recombinant growth hormone from Paralichthys olivaceus

    Science.gov (United States)

    Zang, Xiaonan; Zhang, Xuecheng; Mu, Xiaosheng; Liu, Bin

    2013-03-01

    This study aimed to optimize the purification of recombinant growth hormone from Paralichthys olivaceus. Recombinant flounder growth hormone (r-fGH) was expressed by Escherichia coli in form of inclusion body or as soluble protein under different inducing conditions. The inclusion body was renatured using two recovery methods, i.e., dilution and dialysis. Thereafter, the refolded protein was purified by Glutathione Sepharase 4B affinity chromatography and r-fGH was obtained by cleavage of thrombin. For soluble products, r-fGH was directly purified from the lysates by Glutathione Sepharase 4B affinity chromatography. ELISA-receptor assay demonstrated that despite its low receptor binding activity, the r-fGH purified from refolded inclusion body had a higher yield (2.605 mg L-1) than that from soluble protein (1.964 mg L-1). Of the tested recovery methods, addition of renaturing buffer (pH 8.5) into denatured inclusion body yielded the best recovery rate (17.9%). This work provided an optimized purification method for high recovery of r-fGH, thus contributing to the application of r-fGH to aquaculture.

  7. Method for single crystal growth of photovoltaic perovskite material and devices

    Science.gov (United States)

    Huang, Jinsong; Dong, Qingfeng

    2017-11-07

    Systems and methods for perovskite single crystal growth include using a low temperature solution process that employs a temperature gradient in a perovskite solution in a container, also including at least one small perovskite single crystal, and a substrate in the solution upon which substrate a perovskite crystal nucleates and grows, in part due to the temperature gradient in the solution and in part due to a temperature gradient in the substrate. For example, a top portion of the substrate external to the solution may be cooled.

  8. Model for determining vapor equilibrium rates in the hanging drop method for protein crystal growth

    Science.gov (United States)

    Baird, James K.; Frieden, Richard W.; Meehan, E. J., Jr.; Twigg, Pamela J.; Howard, Sandra B.; Fowlis, William A.

    1987-01-01

    An engineering analysis of the rate of evaporation of solvent in the hanging drop method of protein crystal growth is presented. Results are applied to 18 drop and well arrangements commonly encountered in the laboratory. The chemical nature of the salt, drop size and shape, drop concentration, well size, well concentration, and temperature are taken into account. The rate of evaporation increases with temperature, drop size, and the salt concentration difference between the drop and the well. The evaporation in this model possesses no unique half-life. Once the salt in the drop achieves 80 percent of its final concentration, further evaporation suffers from the law of diminishing returns.

  9. Optimization of Growth Medium for Efficient Cultivation of Lactobacillus salivarius i 24 using Response Surface Method

    Directory of Open Access Journals (Sweden)

    Lim, C. H.

    2007-01-01

    Full Text Available Production of Lactobacillus salivarius i 24, a probiotic strain for chicken, was studied in batch fermentation using 500 mL Erlenmeyer flask. Response surface method (RSM was used to optimize the medium for efficient cultivation of the bacterium. The factors investigated were yeast extract, glucose and initial culture pH. A polynomial regression model with cubic and quartic terms was used for the analysis of the experimental data. Estimated optimal conditions of the factors for growth of L. salivarius i 24 were; 3.32 % (w/v glucose, 4.31 % (w/v yeast extract and initial culture pH of 6.10.

  10. A new method to manipulate broiler chicken growth and metabolism: Response to mixed LED light system

    Science.gov (United States)

    Yang, Yefeng; Yu, Yonghua; Pan, Jinming; Ying, Yibin; Zhou, Hong

    2016-05-01

    Present study introduced a new method to manipulate broiler chicken growth and metabolism by mixing the growth-advantage LED. We found that the green/blue LED mixed light system (G-B and G × B) have the similar stimulatory effect on chick body weight with single green light and single blue light (G and B), compared with normal artificial light (P = 0.028). Moreover, the percentage of carcass was significantly greater in the mixed light (G × B) when compared with the single light (P = 0.003). Synchronized with body weight, the mixed light (G-B and G × B) had a significant improved influence on the feed conversion of birds compared with normal light (P = 0.002). A significant improvement in feed conversion were found in mixed light (G × B) compared with single LED light (P = 0.037). G group resulted in a greater high-density lipoprotein cholesterol level than B group (P = 0.002), whereas B group resulted in a greater low-density lipoprotein cholesterol level than G group (P = 0.017). The mixed light significantly increased the birds’ glucose level in comparison with the single light (P = 0.003). This study might establish an effective strategy for maximizing growth of chickens by mixed LED technology.

  11. Development of a microtitre-based spectrophotometric method to monitor Babesia divergens growth in vitro.

    Science.gov (United States)

    Malandrin, Laurence; Marchand, Anne-Marie; Chauvin, Alain

    2004-09-01

    Babesia divergens multiplication cycle involves erythrocyte invasion, intracellular division, and erythrocyte lysis with the simultaneous liberation of hemoglobin. We have decided to set up a spectrophotometric protocol based on hemoglobin concentration in the culture supernatants to monitor B. divergens in vitro growth. After the selection of 405 nm as the most appropriate endpoint hemoglobin wavelength in our conditions (hemoglobin concentration in the supernatant), cultures were standardized [1 x 10(9) red blood cell (RBC)/ml, 1-2.5 x 10(5) infected red blood cell (iRBC)/ml] to allow their monitoring over 3 days. The protocol was then compared to the most commonly used growth measurement methods: parasitemia counting and [(3)H]hypoxanthine incorporation. An excellent correlation was demonstrated between A(405) of the culture supernatant and parasitemia of the iRBC, whatever the RBC concentration used in the medium. This correlation was also evidenced between A(405) and [(3)H]hypoxanthine incorporation for [(3)H]hypoxanthine concentrations lower than 4 microCi/ml. Our assays also highlighted the inhibitory effect of [(3)H]hypoxanthine on B. divergens growth even when used at low concentrations (0.8 microCi/ml) and for a short incorporation duration (24 h). This effect was confirmed by both A(405) and parasitemia counting. In conclusion, A(405) measurement of B. divergens culture supernatant represents a simple, rapid, safe, and reliable way to measure the in vitro growth of this parasite. Generation times of three different B. divergens strains were then determined by the protocol described here and varied between 8 h 36 min and 13 h 8 min.

  12. Solution of Dendritic Growth in Steel by the Novel Point Automata Method

    International Nuclear Information System (INIS)

    Lorbiecka, A Z; Šarler, B

    2012-01-01

    The aim of this paper is the simulation of dendritic growth in steel in two dimensions by a coupled deterministic continuum mechanics heat and species transfer model and a stochastic localized phase change kinetics model taking into account the undercooling, curvature, kinetic, and thermodynamic anisotropy. The stochastic model receives temperature and concentration information from the deterministic model and the deterministic heat, and species diffusion equations receive the solid fraction information from the stochastic model. The heat and species transfer models are solved on a regular grid by the standard explicit Finite Difference Method (FDM). The phase-change kinetics model is solved by a novel Point Automata (PA) approach. The PA method was developed [1] in order to circumvent the mesh anisotropy problem, associated with the classical Cellular Automata (CA) method. The PA approach is established on randomly distributed points and neighbourhood configuration, similar as appears in meshless methods. A comparison of the PA and CA methods is shown. It is demonstrated that the results with the new PA method are not sensitive to the crystallographic orientations of the dendrite.

  13. Estimation of Staphylococcus aureus growth parameters from turbidity data: characterization of strain variation and comparison of methods.

    Science.gov (United States)

    Lindqvist, R

    2006-07-01

    Turbidity methods offer possibilities for generating data required for addressing microorganism variability in risk modeling given that the results of these methods correspond to those of viable count methods. The objectives of this study were to identify the best approach for determining growth parameters based on turbidity data and use of a Bioscreen instrument and to characterize variability in growth parameters of 34 Staphylococcus aureus strains of different biotypes isolated from broiler carcasses. Growth parameters were estimated by fitting primary growth models to turbidity growth curves or to detection times of serially diluted cultures either directly or by using an analysis of variance (ANOVA) approach. The maximum specific growth rates in chicken broth at 17 degrees C estimated by time to detection methods were in good agreement with viable count estimates, whereas growth models (exponential and Richards) underestimated growth rates. Time to detection methods were selected for strain characterization. The variation of growth parameters among strains was best described by either the logistic or lognormal distribution, but definitive conclusions require a larger data set. The distribution of the physiological state parameter ranged from 0.01 to 0.92 and was not significantly different from a normal distribution. Strain variability was important, and the coefficient of variation of growth parameters was up to six times larger among strains than within strains. It is suggested to apply a time to detection (ANOVA) approach using turbidity measurements for convenient and accurate estimation of growth parameters. The results emphasize the need to consider implications of strain variability for predictive modeling and risk assessment.

  14. An application of the variable-r method to subpopulation growth rates in a 19th century agricultural population

    Directory of Open Access Journals (Sweden)

    Corey Sparks

    2009-07-01

    Full Text Available This paper presents an analysis of the differential growth rates of the farming and non-farming segments of a rural Scottish community during the 19th and early 20th centuries using the variable-r method allowing for net migration. Using this method, I find that the farming population of Orkney, Scotland, showed less variability in their reproduction and growth rates than the non-farming population during a period of net population decline. I conclude by suggesting that the variable-r method can be used in general cases where the relative growth of subpopulations or subpopulation reproduction is of interest.

  15. Simple and convenient preparation of Au-Pt core-shell nanoparticles on surface via a seed growth method

    International Nuclear Information System (INIS)

    Qian Lei; Sha Yufang; Yang Xiurong

    2006-01-01

    Au-Pt core-shell nanoparticles were prepared on glass surface by a seed growth method. Gold nanoparticles were used as seeds and ascorbic acid-H 2 PtCl 6 solutions as growth solutions to deposit Pt shell on the surface of gold nanoparticles. These core-shell nanoparticles and their growth process were examined by UV-Vis spectroscopy, X-ray photoelectron spectroscopy, atomic force microscopy and field-emission environmental scanning electron microscopy and the results indicated that the deposition speed was fast and nanoparticles with obvious core-shell structure could be obtained after 2 min. Moreover, this seed growth method for preparation of the core-shell nanoparticles is simple and convenient compared with other seed growth methods with NH 4 OH as a mild reductant. In addition, electrochemical experiments indicated that these Au-Pt core-shell nanoparticles had similar electrochemical properties to those of the bulk Pt electrode

  16. Long-term response to recombinant human growth hormone treatment: a new predictive mathematical method.

    Science.gov (United States)

    Migliaretti, G; Ditaranto, S; Guiot, C; Vannelli, S; Matarazzo, P; Cappello, N; Stura, I; Cavallo, F

    2018-07-01

    Recombinant GH has been offered to GH-deficient (GHD) subjects for more than 30 years, in order to improve height and growth velocity in children and to enhance metabolic effects in adults. The aim of our work is to describe the long-term effect of rhGH treatment in GHD pediatric patients, suggesting a growth prediction model. A homogeneous database is defined for diagnosis and treatment modalities, based on GHD patients afferent to Hospital Regina Margherita in Turin (Italy). In this study, 232 GHD patients are selected (204 idiopathic GHD and 28 organic GHD). Each measure is shown in terms of mean with relative standard deviations (SD) and 95% confidence interval (95% CI). To estimate the final height of each patient on the basis of few measures, a mathematical growth prediction model [based on Gompertzian function and a mixed method based on the radial basis functions (RBFs) and the particle swarm optimization (PSO) models] was performed. The results seem to highlight the benefits of an early start of treatment, further confirming what is suggested by the literature. Generally, the RBF-PSO method shows a good reliability in the prediction of the final height. Indeed, RMSE is always lower than 4, i.e., in average the forecast will differ at most of 4 cm to the real value. In conclusion, the large and accurate database of Italian GHD patients allowed us to assess the rhGH treatment efficacy and compare the results with those obtained in other Countries. Moreover, we proposed and validated a new mathematical model forecasting the expected final height after therapy which was validated on our cohort.

  17. The Art of Memory and the Growth of the Scientific Method

    Directory of Open Access Journals (Sweden)

    Gopal P. Sarma

    2015-07-01

    Full Text Available I argue that European schools of thought on memory and memorization were critical in enabling growth of the scientific method. After giving a historical overview of the development of the memory arts from ancient Greece through 17th century Europe, I describe how the Baconian viewpoint on the scientific method was fundamentally part of a culture and a broader dialogue that conceived of memorization as a foundational methodology for structuring knowledge and for developing symbolic means for representing scientific concepts. The principal figures of this intense and rapidly evolving intellectual milieu included some of the leading thinkers traditionally associated with the scientific revolution; among others, Francis Bacon, Renes Descartes, and Gottfried Leibniz. I close by examining the acceleration of mathematical thought in light of the art of memory and its role in 17th century philosophy, and in particular, Leibniz’s project to develop a universal calculus.

  18. Evaluation of immunological methods for detection of bovine growth hormone (BGH) produced in E. coli

    International Nuclear Information System (INIS)

    Rosner, A.; Zwang, R.; Aviv, H.

    1982-01-01

    The use of several immunological methods for studies on synthesis of bovine growth hormone (BGH) by E. coli is described here. The ELISA procedure was shown to be the least sensitive and unfit for assaying BGH in E. coli extracts. The solid-phase radioimmunoassay (RIA) proved to be highly sensitive, but since E. coli extract itself (not containing BGH) interfered with the immunological reaction, its use for measuring BGH was practically limited. The best adequate procedure proved to be radioimmunoassay in solution, which was not adversely affected by the E. coli extract and was sufficiently sensitive to detect nanogram quantities of BGH. The size of the BGH produced by normal bacterial cells was investigated by protein fractionation, transfer to nitrocellulose paper and detection by anti-BGH serum. This method also served for semi-quantitative determination of BGH in the bacterial extract. (Auth.)

  19. Evaluation of immunological methods for detection of bovine growth hormone (BGH) produced in E. coli

    Energy Technology Data Exchange (ETDEWEB)

    Rosner, A; Zwang, R; Aviv, H [Weizmann Institute of Science, Rehovot (Israel). Dept. of Virology

    1982-07-30

    The use of several immunological methods for studies on synthesis of bovine growth hormone (BGH) by E. coli is described here. The ELISA procedure was shown to be the least sensitive and unfit for assaying BGH in E. coli extracts. The solid-phase radioimmunoassay (RIA) proved to be highly sensitive, but since E. coli extract itself (not containing BGH) interfered with the immunological reaction, its use for measuring BGH was practically limited. The most adequate procedure proved to be radioimmunoassay in solution, which was not adversely affected by the E. coli extract and was sufficiently sensitive to detect nanogram quantities of BGH. The size of the BGH produced by normal bacterial cells was investigated by protein fractionation, transfer to nitrocellulose paper and detection by anti-BGH serum. This method also served for semi-quantitative determination of BGH in the bacterial extract.

  20. A new method to produce macroporous Mg-phosphate bone growth substitutes

    Energy Technology Data Exchange (ETDEWEB)

    Babaie, Elham, E-mail: Elham.Babaie@rockets.utoledo.edu [Department of Biomedical Engineering, University of Toledo, Toledo, OH 43606 (United States); Lin, Boren [Department of Biomedical Engineering, University of Toledo, Toledo, OH 43606 (United States); Bhaduri, Sarit B. [Department of Mechanical, Industrial and Manufacturing Engineering, University of Toledo, Toledo, OH 43606 (United States); Department of Surgery (Dentistry), University of Toledo, Toledo, OH 43614 (United States)

    2017-06-01

    This paper is a sequel to our previous effort in developing Mg-phosphate orthopedic cements using amorphous Mg-phosphate (AMP) as the precursor. In this paper, we report a new real-time in situ technique to create macroporous bone growth substitute (BGS). The method uses biodegradable Mg-particles as the porogen. As opposed to the conventional wisdom of providing corrosion protection layers to biodegradable Mg-alloys, the present method uses the fast corrosion kinetics of Mg to create macropores in real time during the setting of the cement. An aqueous solution of PVA was used as the setting solution. Using this technique, a macroporous cement containing up to 91% porosity is obtained, as determined by pycnometry. Due to formation of H{sub 2} gas bubbles from corrosion of Mg, the cement becomes macroporous. The pore sizes as big as 760 μm were observed. The results of SBF soaking indicated change in crystallinity as confirmed via scanning electron microscopy (SEM) and X-ray diffraction (XRD). Our in vitro cytocompatibility evaluation also revealed that the macroporous bone growth substitute composed of bobierrite is cytocompatible and can improve gene expression. - Highlights: • We report a new real time, in situ technique to fabricate macroporous bone grafts. • Self-corroding Mg granules act as porogens. • Compositions containing AMP and PVA self-set within a reasonable time. • The final bone graft substitute showed promising biocompatibility. • The results provide important information on the porosity content and bioactivity.

  1. Solutions for implementing time-of-flight techniques in low-angle neutron scattering, as realized on the Low-Q Diffractometer at Los Alamos

    International Nuclear Information System (INIS)

    Hjelm, R.P. Jr.; Seeger, P.A.

    1992-01-01

    The implementation of small-angle (Low-momentum transfer) neutron scattering at pulsed spallation sources, using time of flight methods, has meant the introduction of some new ideas in instrument design, data acquisition, data reduction and computer management of the experiment and the data. Here we recount some of the salient aspects of solutions for implementing time of fight small-angle neutron scattering instruments at pulsed sources, as realized on the Low-Q Diffractometer, LQD, at Los Alamos. We consider, fortlier, some of the problems that are yet to be solved, and take a short excursion into the future of SANS instrumentation at pulsed sources

  2. A new method for evaluating forest thinning: growth dominance in managed Pinus resinosa stands

    Science.gov (United States)

    John B. Bradford; Anthony W. D' Amato; Brian J. Palik; Shawn. Fraver

    2010-01-01

    Growth dominance is a relatively new, simple, quantitative metric of within-stand individual tree growth patterns, and is defined as positive when larger trees in the stand display proportionally greater growth than smaller trees, and negative when smaller trees display proportionally greater growth than larger trees. We examined long-term silvicultural experiments in...

  3. Identification of growth phases and influencing factors in cultivations with AGE1.HN cells using set-based methods.

    Directory of Open Access Journals (Sweden)

    Steffen Borchers

    Full Text Available Production of bio-pharmaceuticals in cell culture, such as mammalian cells, is challenging. Mathematical models can provide support to the analysis, optimization, and the operation of production processes. In particular, unstructured models are suited for these purposes, since they can be tailored to particular process conditions. To this end, growth phases and the most relevant factors influencing cell growth and product formation have to be identified. Due to noisy and erroneous experimental data, unknown kinetic parameters, and the large number of combinations of influencing factors, currently there are only limited structured approaches to tackle these issues. We outline a structured set-based approach to identify different growth phases and the factors influencing cell growth and metabolism. To this end, measurement uncertainties are taken explicitly into account to bound the time-dependent specific growth rate based on the observed increase of the cell concentration. Based on the bounds on the specific growth rate, we can identify qualitatively different growth phases and (in-validate hypotheses on the factors influencing cell growth and metabolism. We apply the approach to a mammalian suspension cell line (AGE1.HN. We show that growth in batch culture can be divided into two main growth phases. The initial phase is characterized by exponential growth dynamics, which can be described consistently by a relatively simple unstructured and segregated model. The subsequent phase is characterized by a decrease in the specific growth rate, which, as shown, results from substrate limitation and the pH of the medium. An extended model is provided which describes the observed dynamics of cell growth and main metabolites, and the corresponding kinetic parameters as well as their confidence intervals are estimated. The study is complemented by an uncertainty and outlier analysis. Overall, we demonstrate utility of set-based methods for analyzing cell

  4. Identification of growth phases and influencing factors in cultivations with AGE1.HN cells using set-based methods.

    Science.gov (United States)

    Borchers, Steffen; Freund, Susann; Rath, Alexander; Streif, Stefan; Reichl, Udo; Findeisen, Rolf

    2013-01-01

    Production of bio-pharmaceuticals in cell culture, such as mammalian cells, is challenging. Mathematical models can provide support to the analysis, optimization, and the operation of production processes. In particular, unstructured models are suited for these purposes, since they can be tailored to particular process conditions. To this end, growth phases and the most relevant factors influencing cell growth and product formation have to be identified. Due to noisy and erroneous experimental data, unknown kinetic parameters, and the large number of combinations of influencing factors, currently there are only limited structured approaches to tackle these issues. We outline a structured set-based approach to identify different growth phases and the factors influencing cell growth and metabolism. To this end, measurement uncertainties are taken explicitly into account to bound the time-dependent specific growth rate based on the observed increase of the cell concentration. Based on the bounds on the specific growth rate, we can identify qualitatively different growth phases and (in-)validate hypotheses on the factors influencing cell growth and metabolism. We apply the approach to a mammalian suspension cell line (AGE1.HN). We show that growth in batch culture can be divided into two main growth phases. The initial phase is characterized by exponential growth dynamics, which can be described consistently by a relatively simple unstructured and segregated model. The subsequent phase is characterized by a decrease in the specific growth rate, which, as shown, results from substrate limitation and the pH of the medium. An extended model is provided which describes the observed dynamics of cell growth and main metabolites, and the corresponding kinetic parameters as well as their confidence intervals are estimated. The study is complemented by an uncertainty and outlier analysis. Overall, we demonstrate utility of set-based methods for analyzing cell growth and

  5. Study Of Soot Growth And Nucleation By A Time-Resolved Synchrotron Radiation Based X-Ray Absorption Method

    National Research Council Canada - National Science Library

    Mitchell, Judith I

    2001-01-01

    This report results from a contract tasking University of Rennes I as follows: The contractor will perform a study of soot growth and nucleation by a time-resolved synchrotron radiation based x-ray absorption method...

  6. Determining individual variation in growth and its implication for life-history and population processes using the empirical Bayes method.

    Directory of Open Access Journals (Sweden)

    Simone Vincenzi

    2014-09-01

    Full Text Available The differences in demographic and life-history processes between organisms living in the same population have important consequences for ecological and evolutionary dynamics. Modern statistical and computational methods allow the investigation of individual and shared (among homogeneous groups determinants of the observed variation in growth. We use an Empirical Bayes approach to estimate individual and shared variation in somatic growth using a von Bertalanffy growth model with random effects. To illustrate the power and generality of the method, we consider two populations of marble trout Salmo marmoratus living in Slovenian streams, where individually tagged fish have been sampled for more than 15 years. We use year-of-birth cohort, population density during the first year of life, and individual random effects as potential predictors of the von Bertalanffy growth function's parameters k (rate of growth and L∞ (asymptotic size. Our results showed that size ranks were largely maintained throughout marble trout lifetime in both populations. According to the Akaike Information Criterion (AIC, the best models showed different growth patterns for year-of-birth cohorts as well as the existence of substantial individual variation in growth trajectories after accounting for the cohort effect. For both populations, models including density during the first year of life showed that growth tended to decrease with increasing population density early in life. Model validation showed that predictions of individual growth trajectories using the random-effects model were more accurate than predictions based on mean size-at-age of fish.

  7. Determining individual variation in growth and its implication for life-history and population processes using the empirical Bayes method.

    Science.gov (United States)

    Vincenzi, Simone; Mangel, Marc; Crivelli, Alain J; Munch, Stephan; Skaug, Hans J

    2014-09-01

    The differences in demographic and life-history processes between organisms living in the same population have important consequences for ecological and evolutionary dynamics. Modern statistical and computational methods allow the investigation of individual and shared (among homogeneous groups) determinants of the observed variation in growth. We use an Empirical Bayes approach to estimate individual and shared variation in somatic growth using a von Bertalanffy growth model with random effects. To illustrate the power and generality of the method, we consider two populations of marble trout Salmo marmoratus living in Slovenian streams, where individually tagged fish have been sampled for more than 15 years. We use year-of-birth cohort, population density during the first year of life, and individual random effects as potential predictors of the von Bertalanffy growth function's parameters k (rate of growth) and L∞ (asymptotic size). Our results showed that size ranks were largely maintained throughout marble trout lifetime in both populations. According to the Akaike Information Criterion (AIC), the best models showed different growth patterns for year-of-birth cohorts as well as the existence of substantial individual variation in growth trajectories after accounting for the cohort effect. For both populations, models including density during the first year of life showed that growth tended to decrease with increasing population density early in life. Model validation showed that predictions of individual growth trajectories using the random-effects model were more accurate than predictions based on mean size-at-age of fish.

  8. A low-angle normal fault and basement structures within the Enping Sag, Pearl River Mouth Basin: Insights into late Mesozoic to early Cenozoic tectonic evolution of the South China Sea area

    Science.gov (United States)

    Ye, Qing; Mei, Lianfu; Shi, Hesheng; Shu, Yu; Camanni, Giovanni; Wu, Jing

    2018-04-01

    The basement structure of the Cenozoic Enping Sag, within the Pearl River Mouth Basin on the northern margin of South China Sea, is revealed by borehole-constrained high-quality 3D seismic reflection data. Such data suggest that the Enping Sag is bounded in the north by a low-angle normal fault. We interpret this low-angle normal fault to have developed as the result of the reactivation of a pre-existing thrust fault part of a pre-Cenozoic thrust system. This is demonstrated by the selective reactivation of the pre-existing thrust and by diffuse contractional deformation recognized from the accurate analysis of basement reflections. Another significant result of this study is the finding of some residual rift basins within the basement of the Enping Sag. Both the thrust system and the residual basins are interpreted to have developed after the emplacement of continental margin arc-related granitoids (J3-K1) that define the basement within the study area. Furthermore, seismic sections show that the pre-existing residual rift basins are offset by the main thrust fault and they are both truncated by the Tg unconformity. These structural relationships, interpreted in the frame of previous studies, help us to reconstruct a six-event structural evolution model for the Enping Sag from the late Mesozoic to the early Cenozoic. In particular, we interpret the residual rift basins to have formed as the result of back-arc extension due to the slab roll-back of the Paleo-Pacific Plate subduction in the early K2. The thrust system has recorded a compressional event in the late K2 that followed the back-arc extension in the SCS area. The mechanism of this compressional event is still to be clarified, and might be related to continuous subduction of the Paleo-Pacific Plate or to the continent-continent collision between a micro-continental block and the South China margin.

  9. Evaporation kinetics in the hanging drop method of protein crystal growth

    Science.gov (United States)

    Baird, James K.; Frieden, Richard W.; Meehan, E. J., Jr.; Twigg, Pamela J.; Howard, Sandra B.; Fowlis, William A.

    1987-01-01

    An engineering analysis of the rate of evaporation of solvent in the hanging drop method of protein crystal growth is presented; these results are applied to 18 different drop and well arrangements commonly encountered in the laboratory, taking into account the chemical nature of the salt, the drop size and shape, the drop concentration, the well size, the well concentration, and the temperature. It is found that the rate of evaporation increases with temperature, drop size, and with the salt concentration difference between the drop and the well. The evaporation possesses no unique half-life. Once the salt in the drop achieves about 80 percent of its final concentration, further evaporation suffers from the law of diminishing returns.

  10. Growth of polyaniline nanofibers for supercapacitor applications using successive ionic layer adsorption and reaction (SILAR) method

    Energy Technology Data Exchange (ETDEWEB)

    Deshmukh, P. R.; Pusawale, S. N.; Shinde, N. M.; Lokhande, C. D. [Shivaji University, Kolhapur (India)

    2014-07-15

    We report the synthesis of polyaniline nanofibers using the successive ionic layer adsorption and reaction (SILAR) method. The structural study shows the amorphous nature of polyaniline. The formation of polyaniline nanofibers has been revealed by scanning electron microscopy (SEM) whereas the confirmation of polyaniline material is obtained from Fourier transform infrared (FT-IR) spectroscopy. A plausible explanation illustrating the growth mechanism is presented. A maximum specific capacitance of 1078 F·g{sup -1} at a scan rate of 5 mV·s{sup -1} is obtained. The charge-discharge behavior shows a maximum specific power of 1.2 kW·kg{sup -1} and specific energy of 64 Wh·kg{sup -1}. The ease of the synthesis and the interesting electrochemical properties indicate that polyaniline nanofibers are promising materials for supercapacitor applications.

  11. Growth of polyaniline nanofibers for supercapacitor applications using successive ionic layer adsorption and reaction (SILAR) method

    International Nuclear Information System (INIS)

    Deshmukh, P. R.; Pusawale, S. N.; Shinde, N. M.; Lokhande, C. D.

    2014-01-01

    We report the synthesis of polyaniline nanofibers using the successive ionic layer adsorption and reaction (SILAR) method. The structural study shows the amorphous nature of polyaniline. The formation of polyaniline nanofibers has been revealed by scanning electron microscopy (SEM) whereas the confirmation of polyaniline material is obtained from Fourier transform infrared (FT-IR) spectroscopy. A plausible explanation illustrating the growth mechanism is presented. A maximum specific capacitance of 1078 F·g -1 at a scan rate of 5 mV·s -1 is obtained. The charge-discharge behavior shows a maximum specific power of 1.2 kW·kg -1 and specific energy of 64 Wh·kg -1 . The ease of the synthesis and the interesting electrochemical properties indicate that polyaniline nanofibers are promising materials for supercapacitor applications.

  12. On a separating method for mixed-modes crack growth in wood material using image analysis

    Science.gov (United States)

    Moutou Pitti, R.; Dubois, F.; Pop, O.

    2010-06-01

    Due to the complex wood anatomy and the loading orientation, the timber elements are subjected to a mixed-mode fracture. In these conditions, the crack tip advance is characterized by mixed-mode kinematics. In order to characterize the fracture process function versus the loading orientation, a new mixed-mode crack growth timber specimen is proposed. In the present paper, the design process and the experimental validation of this specimen are proposed. Using experimental results, the energy release rate is calculated for several modes. The calculi consist on the separation of each fracture mode. The design of the specimen is based on the analytical approach and numerical simulation by finite element method. The specimen particularity is the stability of the crack propagation under a force control.

  13. Using growth-based methods to determine direct effects of salinity on soil microbial communities

    Science.gov (United States)

    Rath, Kristin; Rousk, Johannes

    2015-04-01

    Soil salinization is a widespread agricultural problem and increasing salt concentrations in soils have been found to be correlated with decreased microbial activity. A central challenge in microbial ecology is to link environmental factors, such as salinity, to responses in the soil microbial community. That is, it can be difficult to distinguish direct from indirect effects. In order to determine direct salinity effects on the community we employed the ecotoxicological concept of Pollution-Induced Community Tolerance (PICT). This concept is built on the assumption that if salinity had an ecologically relevant effect on the community, it should have selected for more tolerant species and strains, resulting in an overall higher community tolerance to salt in communities from saline soils. Growth-based measures, such as the 3H-leucine incorporation into bacterial protein , provide sensitive tools to estimate community tolerance. They can also provide high temporal resolution in tracking changes in tolerance over time. In our study we used growth-based methods to investigate: i) at what levels of salt exposure and over which time scales salt tolerance can be induced in a non-saline soil, and (ii) if communities from high salinity sites have higher tolerance to salt exposure along natural salinity gradients. In the first part of the study, we exposed a non-saline soil to a range of salinities and monitored the development of community tolerance over time. We found that community tolerance to intermediate salinities up to around 30 mg NaCl per g soil can be induced at relatively short time scales of a few days, providing evidence that microbial communities can adapt rapidly to changes in environmental conditions. In the second part of the study we used soil samples originating from natural salinity gradients encompassing a wide range of salinity levels, with electrical conductivities ranging from 0.1 dS/m to >10 dS/m. We assessed community tolerance to salt by

  14. Growth and characterization of magnetite-maghemite thin films by the dip coating method

    Energy Technology Data Exchange (ETDEWEB)

    Velásquez, A. A., E-mail: avelas26@eafit.edu.edu.co; Arnedo, A. [Universidad EAFIT, Grupo de Electromagnetismo Aplicado (Colombia)

    2017-11-15

    We present the process of growth and characterization of magnetite-maghemite thin films obtained by the dip coating method. The thin films were deposited on glass substrates, using a ferrofluid of nanostructured magnetite-maghemite particles as precursor solution. During the growth of the films the following parameters were controlled: number of dips of the substrates, dip velocity of the substrates and drying times. The films were characterized by Atomic Force Microscopy, Scanning Elelectron Microscopy, four-point method for resistance measurement, Room Temperature Mössbauer Spectroscopy and Hall effect. Mössbauer measurements showed the presence of a sextet attributed to maghemite (γ-Fe{sub 2}O{sub 3}) and two doublets attributed to superparamagnetic magnetite (Fe{sub 3}O{sub 4}), indicating a distribution of oxidation states of the iron as well as a particle size distribution of the magnetic phases in the films. Atomic force microscopy measurements showed that the films cover quasi uniformly the substrates, existing in them some pores with sub-micron size. Scanning Electron Microscopy measurements showed a uniform structure in the films, with spherical particles with size around 10 nm. Voltage versus current measurements showed an ohmic response of the films for currents between 0 and 100 nA. On the other hand, Hall effect measurements showed a nonlinear response of the Hall voltage with the magnetic flux density applied perpendicular to the plane of the films, however the response is fairly linear for magnetic flux densities between 0.15 and 0.35 T approximately. The results suggest that the films are promising for application as magnetic flux density sensors.

  15. Growth and characterization of magnetite-maghemite thin films by the dip coating method

    International Nuclear Information System (INIS)

    Velásquez, A. A.; Arnedo, A.

    2017-01-01

    We present the process of growth and characterization of magnetite-maghemite thin films obtained by the dip coating method. The thin films were deposited on glass substrates, using a ferrofluid of nanostructured magnetite-maghemite particles as precursor solution. During the growth of the films the following parameters were controlled: number of dips of the substrates, dip velocity of the substrates and drying times. The films were characterized by Atomic Force Microscopy, Scanning Elelectron Microscopy, four-point method for resistance measurement, Room Temperature Mössbauer Spectroscopy and Hall effect. Mössbauer measurements showed the presence of a sextet attributed to maghemite (γ-Fe_2O_3) and two doublets attributed to superparamagnetic magnetite (Fe_3O_4), indicating a distribution of oxidation states of the iron as well as a particle size distribution of the magnetic phases in the films. Atomic force microscopy measurements showed that the films cover quasi uniformly the substrates, existing in them some pores with sub-micron size. Scanning Electron Microscopy measurements showed a uniform structure in the films, with spherical particles with size around 10 nm. Voltage versus current measurements showed an ohmic response of the films for currents between 0 and 100 nA. On the other hand, Hall effect measurements showed a nonlinear response of the Hall voltage with the magnetic flux density applied perpendicular to the plane of the films, however the response is fairly linear for magnetic flux densities between 0.15 and 0.35 T approximately. The results suggest that the films are promising for application as magnetic flux density sensors.

  16. Effect of fertilization methods on growth of pear trees, yielding and fruit quality

    Directory of Open Access Journals (Sweden)

    Tomasz Lipa

    2013-04-01

    Full Text Available The experiment was carried out in the commercial orchard near Lublin on five-year old pear trees of two cultivars: ‘Conference’and ‘Lukasowka’, planted on Quince MA. The objective of the study was evaluated the reaction of pear on the method of application of fertilizers. In the early spring the surface broadcasting of fertilizers was used (N – 71,5 kg, P 2O5 – 33,0 kg, K 2 O – 114,0 kg and from the May to the middle of August the fertigation was applied (N – 76,4 kg, P 2O5 – 49,5 kg, K 2 O – 84,2 kg. Method of fertilizer’s applications had no significant effect on the growth of evaluated trees. There were no differences in quantity of yield in dependence on the method of fertilization. In the case of cv. ‘Lukasowka’the beneficial influence of the way of fertilization on morphology of fruits (their diameter, height and mass was stated. Such an effect was not observed in the case of the ‘Conference’.

  17. Study on the Growth of Holes in Cold Spraying via Numerical Simulation and Experimental Methods

    Directory of Open Access Journals (Sweden)

    Guosheng Huang

    2016-12-01

    Full Text Available Cold spraying is a promising method for rapid prototyping due to its high deposition efficiency and high-quality bonding characteristic. However, many researchers have noticed that holes cannot be replenished and will grow larger and larger once formed, which will significantly decrease the deposition efficiency. No work has yet been done on this problem. In this paper, a computational simulation method was used to investigate the origins of these holes and the reasons for their growth. A thick copper coating was deposited around the pre-drilled, micro-size holes using a cold spraying method on copper substrate to verify the simulation results. The results indicate that the deposition efficiency inside the hole decreases as the hole become deeper and narrower. The repellant force between the particles perpendicular to the impaction direction will lead to porosity if the particles are too close. There is a much lower flattening ratio for successive particles if they are too close at the same location, because the momentum energy contributes to the former particle’s deformation. There is a high probability that the above two phenomena, resulting from high powder-feeding rate, will form the original hole, which will grow larger and larger once it is formed. It is very important to control the powder feeding rate, but the upper limit is yet to be determined by further simulation and experimental investigation.

  18. Effectiveness of the cervical vertebral maturation method to predict postpeak circumpubertal growth of craniofacial structures.

    Science.gov (United States)

    Fudalej, Piotr; Bollen, Anne-Marie

    2010-01-01

    Our aim was to assess effectiveness of the cervical vertebral maturation (CVM) method to predict circumpubertal craniofacial growth in the postpeak period. The CVM stage was determined in 176 subjects (51 adolescent boys and 125 adolescent girls) on cephalograms taken at the end of treatment (T2; mean ages, 15.75 years [boys] and 15.23 years [girls]) in subjects from the postretention database at the University of Washington in Seattle. Craniofacial growth was evaluated from the following measurements on cephalograms at T2 and end of follow-up (T3) (mean ages, 29.01 years [men] and 28.08 years [women]): condylion to gnathion, condylion to gonion, gonion to gnathion, sella to gnathion, nasion to menton, anterior nasal spine to menton, and sella to gonion. The change of each variable from T2 to T3 was assessed with paired t tests. Parametric (t tests or analysis of variance [ANOVA]) or nonparametric (Mann-Whitney or Kruskal-Wallis) tests were used to detect intergroup differences. One hundred eight subjects (35 boys, 73 girls) demonstrated CVM stage 3, 56 (16 boys, 40 girls) were in CVM stage 4, and 12 (all girls) were in CVM stage 5 at T2. Intrasex comparisons showed that boys in CVM stages 3 and 4 could be differentiated regarding changes of all variables. In the girls, only those in CVM stages 3 and 4 could be differentiated based on the amount of changes of 2 measurements: condylion to gonion and sella to gonion. Intersex comparisons showed that boys in CVM stage 3 had significantly more changes than girls (P <0.01). Boys in CVM stage 4 showed significant differences compared with girls in CVM stage 4 for only 2 variables (sella to gonion and condylion to gonion; P <0.001 and P = 0.012, respectively). The CVM method was modestly effective in determining the amount of postpeak circumpubertal craniofacial growth. Copyright 2010 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

  19. Effect of culture methods on individual variation in the growth of sea cucumber Apostichopus japonicus within a cohort and family

    Science.gov (United States)

    Qiu, Tianlong; Zhang, Libin; Zhang, Tao; Bai, Yucen; Yang, Hongsheng

    2014-07-01

    There is substantial individual variation in the growth rates of sea cucumber Apostichopus japonicus individuals. This necessitates additional work to grade the seed stock and lengthens the production period. We evaluated the influence of three culture methods (free-mixed, isolated-mixed, isolated-alone) on individual variation in growth and assessed the relationship between feeding, energy conversion efficiency, and individual growth variation in individually cultured sea cucumbers. Of the different culture methods, animals grew best when reared in the isolated-mixed treatment (i.e., size classes were held separately), though there was no difference in individual variation in growth between rearing treatment groups. The individual variation in growth was primarily attributed to genetic factors. The difference in food conversion efficiency caused by genetic differences among individuals was thought to be the origin of the variance. The level of individual growth variation may be altered by interactions among individuals and environmental heterogeneity. Our results suggest that, in addition to traditional seed grading, design of a new kind of substrate that changes the spatial distribution of sea cucumbers would effectively enhance growth and reduce individual variation in growth of sea cucumbers in culture.

  20. Life cycle and population growth rate of Caenorhabditis elegans studied by a new method.

    Science.gov (United States)

    Muschiol, Daniel; Schroeder, Fabian; Traunspurger, Walter

    2009-05-16

    The free-living nematode Caenorhabditis elegans is the predominant model organism in biological research, being used by a huge number of laboratories worldwide. Many researchers have evaluated life-history traits of C. elegans in investigations covering quite different aspects such as ecotoxicology, inbreeding depression and heterosis, dietary restriction/supplement, mutations, and ageing. Such traits include juvenile growth rates, age at sexual maturity, adult body size, age-specific fecundity/mortality, total reproduction, mean and maximum lifespan, and intrinsic population growth rates. However, we found that in life-cycle experiments care is needed regarding protocol design. Here, we test a recently developed method that overcomes some problems associated with traditional cultivation techniques. In this fast and yet precise approach, single individuals are maintained within hanging drops of semi-fluid culture medium, allowing the simultaneous investigation of various life-history traits at any desired degree of accuracy. Here, the life cycles of wild-type C. elegans strains N2 (Bristol, UK) and MY6 (Münster, Germany) were compared at 20 degrees C with 5 x 10(9) Escherichia coli ml-1 as food source. High-resolution life tables and fecundity schedules of the two strains are presented. Though isolated 700 km and 60 years apart from each other, the two strains barely differed in life-cycle parameters. For strain N2 (n = 69), the intrinsic rate of natural increase (r m d(-1)), calculated according to the Lotka equation, was 1.375, the net reproductive rate (R 0) 291, the mean generation time (T) 90 h, and the minimum generation time (T min) 73.0 h. The corresponding values for strain MY6 (n = 72) were r m = 1.460, R0 = 289, T = 84 h, and T min = 67.3 h. Peak egg-laying rates in both strains exceeded 140 eggs d(-1). Juvenile and early adulthood mortality was negligible. Strain N2 lived, on average, for 16.7 d, while strain MY6 died 2 days earlier; however

  1. Life cycle and population growth rate of Caenorhabditis elegans studied by a new method

    Directory of Open Access Journals (Sweden)

    Schroeder Fabian

    2009-05-01

    Full Text Available Abstract Background The free-living nematode Caenorhabditis elegans is the predominant model organism in biological research, being used by a huge number of laboratories worldwide. Many researchers have evaluated life-history traits of C. elegans in investigations covering quite different aspects such as ecotoxicology, inbreeding depression and heterosis, dietary restriction/supplement, mutations, and ageing. Such traits include juvenile growth rates, age at sexual maturity, adult body size, age-specific fecundity/mortality, total reproduction, mean and maximum lifespan, and intrinsic population growth rates. However, we found that in life-cycle experiments care is needed regarding protocol design. Here, we test a recently developed method that overcomes some problems associated with traditional cultivation techniques. In this fast and yet precise approach, single individuals are maintained within hanging drops of semi-fluid culture medium, allowing the simultaneous investigation of various life-history traits at any desired degree of accuracy. Here, the life cycles of wild-type C. elegans strains N2 (Bristol, UK and MY6 (Münster, Germany were compared at 20°C with 5 × 109 Escherichia coli ml-1 as food source. Results High-resolution life tables and fecundity schedules of the two strains are presented. Though isolated 700 km and 60 years apart from each other, the two strains barely differed in life-cycle parameters. For strain N2 (n = 69, the intrinsic rate of natural increase (rmd-1, calculated according to the Lotka equation, was 1.375, the net reproductive rate (R0 291, the mean generation time (T 90 h, and the minimum generation time (Tmin 73.0 h. The corresponding values for strain MY6 (n = 72 were rm = 1.460, R0 = 289, T = 84 h, and Tmin = 67.3 h. Peak egg-laying rates in both strains exceeded 140 eggs d-1. Juvenile and early adulthood mortality was negligible. Strain N2 lived, on average, for 16.7 d, while strain MY6 died 2 days

  2. The effect of cutting origin and organic plant growth regulator on the growth of Daun Ungu (Graptophyllum pictum) through stem cutting method

    Science.gov (United States)

    Pratama, S. P.; Yunus, A.; Purwanto, E.; Widyastuti, Y.

    2018-03-01

    Graptophyllum pictum is one of medical plants which has important chemical content to treat diseases. Leaf, bark and flower can be used to facilitate menstruation, treat hemorrhoid, constipation, ulcers, ulcers, swelling, and earache. G. pictum is difficult to propagated by seedling due to the long duration of seed formation, thusvegetative propagation is done by stem cutting. The aims of this study are to obtain optimum combination of cutting origin and organic plant growth regulator in various consentration for the growth of Daun Ungu through stem cutting method. This research was conducted at Research center for Medicinal Plant and Traditional DrugTanjungsari, Tegal Gede, Karanganyar in June to August 2016. Origin of cuttings and organic plant growth regulator were used as treatments factor. A completely randomized design (RAL) is used and data were analyzed by F test (ANOVA) with a confidence level of 95%. Any significant differences among treatment followed with Duncan test at a = 5%. The research indicates that longest root was resulted from the treatment of 0,5 ml/l of organic plant growth regulator. The treatment of 1 ml/l is able to increase the fresh and dry weight of root, treatment of 1,5 ml/l of organic plant growth regulator was able to increase the percentage of growing shoots. Treatment of base part as origin of cuttings increases the length, fresh weight and and dry weight of shoot, increase the number of leaves. Interaction treatment between 1 ml/l consentration of organic plant growth regulator and central part origin of cuttings is capable of increasing the leaf area, whereas treatment without organic plant growth regulator and base part as planting material affects the smallest leaf area.

  3. Use of the Delphi method for determining community growth goals inventory: the Nashville experience

    Science.gov (United States)

    Vishwa K. Varma

    1977-01-01

    The author discusses the growth-inducing pressures on Nashville, Tennessee, describes the application of the Delphi technique to develop an inventory of the community's growth goals, and suggests that the development of a list of community goals is a necessary first step toward growth management.

  4. Crack growth prediction method considering interaction between multiple cracks. Growth of surface cracks of dissimilar size under cyclic tensile and bending load

    International Nuclear Information System (INIS)

    Kamaya, Masayuki; Miyokawa, Eiichi; Kikuchi, Masanori

    2011-01-01

    When multiple cracks approach one another, the stress intensity factor is likely to change due to the interaction of the stress field. This causes change in growth rate and shape of cracks. In particular, when cracks are in parallel position to the loading direction, the shape of cracks becomes non-planar. In this study, the complex growth of interacting cracks is evaluated by using the S-Version finite element method, in which local detailed finite element mesh (local mesh) is superposed on coarse finite element model (global mesh) representing the global structure. In order to investigate the effect of interaction on the growth behavior, two parallel surface cracks are subjected to cyclic tensile or bending load. It is shown that the smaller crack is shielded by larger crack due to the interaction and stops growing when the difference in size of two cracks is significant. Based on simulations of various conditions, a procedure and criteria for evaluating crack growth for fitness-for-service assessment is proposed. According to the procedure, the interaction is not necessary to be considered in the crack growth prediction when the difference in size of two cracks exceeds the criterion. (author)

  5. Vertically aligned carbon nanotube growth by pulsed laser deposition and thermal chemical vapor deposition methods

    International Nuclear Information System (INIS)

    Sohn, Jung Inn; Nam, Chunghee; Lee, Seonghoon

    2002-01-01

    We have grown vertically aligned carbon nanotubes on the various substrates such as a planar p-type Si(1 0 0) wafer, porous Si wafer, SiO 2 , Si 3 N 4 , Al 2 O 3 , and Cr by thermal chemical vapor deposition (CVD) at 800 deg.C, using C 2 H 2 gas as a carbon source and Fe catalyst films deposited by a pulsed laser on the substrates. The Fe films were deposited for 5 min by pulsed laser deposition (PLD). The advantage of Fe deposition by PLD over other deposition methods lies in the superior adhesion of Fe to a Si substrate due to high kinetic energies of the generated Fe species. Scanning electron microscopy (SEM) images show that vertically well-aligned carbon nanotubes are grown on Fe nanoparticles formed from the thermal annealing of the Fe film deposited by PLD on the various substrates. Atomic force microscopy (AFM) images show that the Fe film annealed at 800 deg.C is broken to Fe nanoparticles of 10-50 nm in size. We show that the appropriate density of Fe nanoparticles formed from the thermal annealing of the film deposited by PLD is crucial in growing vertically aligned carbon nanotubes. Using a PLD and a lift-off method, we developed the selective growth of carbon nanotubes on a patterned Fe-coated Si substrate

  6. ZnO crystal growth on microelectrode by electrochemical deposition method

    International Nuclear Information System (INIS)

    Kondo, Y; Ashida, A; Nouzu, N; Fujimura, N

    2011-01-01

    Zinc Oxide crystals were grown by constant potential electrochemical deposition method on the substrate with the Pt working electrode which consists of Pt film with large area and μm-sized line and space structured area. In case of depositions with cathodic potential of -0.3V, ZnO crystal is not observed on the micro electrode, but observed on the electrode with large area (0.2 cm 2 ). By using electrolyte with higher pH, ZnO crystal grows on both areas. In case of lower pH, ZnO crystal does not grow on either. From these results, the pH range for growth of ZnO on the microelectrode seems to be higher than that on the electrode with large area. And, it is expected that the pH just on the surface of μm-sized electrode is lower than that in the bulk of electrolyte. Based on these results, it can be concluded that control of the pH in vicinity of the surface is very important to ECD method for micro- and nano-scaled devices.

  7. A method for analyzing changing prison populations: explaining the growth of the elderly in prison.

    Science.gov (United States)

    Luallen, Jeremy; Kling, Ryan

    2014-12-01

    For the past several decades, the U.S. prison system has witnessed a steady and persistent increase in the ages of prison populations. Given the additional costs and burdens placed on prisons as they house older inmates, this aging trend has generated intense interest among policy makers and academics who seek to understand why prison populations are getting older. This article presents a method for evaluating drivers influencing the change in age distributions among prisoners. We define a methodological approach and demonstrate its application using prison data from four states reporting to the Bureau of Justice Statistics' National Corrections Reporting Program. We find that since 2000, the primary driver of overall growth in the elderly populations in prison (defined as inmates over 50) is the increasing admission age of offenders entering prison. Moreover, changes in offense mix and sentence length/time served over the last decade have had significantly less influence on the age composition of prison populations. We also find that the impact of explanatory factors varies across states and offense types. For example, prison admission and exit rates explain much of the change in elderly drug offenders in New York, but not elderly violent offenders, where admission age plays a much stronger explanatory role. Our analysis offers an effective demonstration that supports the use of this method as an important and informative first step toward understanding components of change that affect the problem of prison aging. © The Author(s) 2014.

  8. Gold nanoparticle growth control - Implementing novel wet chemistry method on silicon substrate

    KAUST Repository

    Al-Ameer, Ammar

    2013-04-01

    Controlling particle size, shape, nucleation, and self-assembly on surfaces are some of the main challenges facing electronic device fabrication. In this work, growth of gold nanoparticles over a wide range of sizes was investigated by using a novel wet chemical method, where potassium iodide is used as the reducing solution and gold chloride as the metal precursor, on silicon substrates. Four parameters were studied: soaking time, solution temperature, concentration of the solution of gold chloride, and surface pre-treatment of the substrate. Synthesized nanoparticles were then characterized using scanning electron microscopy (SEM). The precise control of the location and order of the grown gold overlayer was achieved by using focused ion beam (FIB) patterning of a silicon surface, pre-treated with potassium iodide. By varying the soaking time and temperature, different particle sizes and shapes were obtained. Flat geometrical shapes and spherical shapes were observed. We believe, that the method described in this work is potentially a straightforward and efficient way to fabricate gold contacts for microelectronics. © 2013 IEEE.

  9. Growth and properties of ZnO films on polymeric substrate by spray pyrolysis method

    Energy Technology Data Exchange (ETDEWEB)

    Kriisa, Merike; Kärber, Erki [Department of Materials Science, Tallinn University of Technology, Ehitajate tee 5, 19086 Tallinn (Estonia); Krunks, Malle, E-mail: malle.krunks@ttu.ee [Department of Materials Science, Tallinn University of Technology, Ehitajate tee 5, 19086 Tallinn (Estonia); Mikli, Valdek [Centre for Materials Research, Tallinn University of Technology, Ehitajate tee 5, 19086 Tallinn (Estonia); Unt, Tarmo; Kukk, Mart; Mere, Arvo [Department of Materials Science, Tallinn University of Technology, Ehitajate tee 5, 19086 Tallinn (Estonia)

    2014-03-31

    The growth of ZnO layers deposited by spray pyrolysis on polymeric substrate was studied. Zinc acetate precursor solution was sprayed onto preheated polyimide (PI) and glass reference substrates at 380 °C. The structural, morphological, optical and electrical properties of the layers were measured by X-ray diffraction, scanning electron microscopy, optical spectroscopy and van der Pauw and Hall method. ZnO:In layers could be grown on PI when deposited onto undoped ZnO layer acting as a buffer layer on PI. Independent of the substrate type, the ZnO/ZnO:In bilayer showed a mixed morphology from smooth canvas-like surface to large scrolled belt grains dependent on buffer layer morphology. Due to the formation of scrolled belts, the ZnO:In layer shows no preferential orientation, yet the preferred orientation of the ZnO buffer crystallites is (100) plane parallel to the substrate. The bilayers deposited on PI exhibit high light scattering capability (haze factor of 85–95% in the spectral region of 350–1500 nm). The resistivity of the ZnO:In film in bilayer on PI is 4.4 × 10{sup −2} Ω cm mainly due to low carrier mobility of 1.5 cm{sup 2}/Vs, the carrier concentration is 10{sup 20} cm{sup −3}. - Highlights: • ZnO:In layers were grown on polyimide substrate by spray pyrolysis. • The buffer layer morphology is controlled by the layer thickness and spray rate. • ZnO/ZnO:In bilayer morphology is dependent on the surface of buffer layer. • Rough buffer layer leads to rough bilayer with scrolled belts (diameter of 2–6 μm). • Due to scrolled belts layers show no preferential growth yet highly scatter light.

  10. Sequential purification and crystal growth for the production of low cost silicon substrates. Quarterly technical progress report No. 1, 15 September 1979-31 December 1979

    Energy Technology Data Exchange (ETDEWEB)

    Liaw, M.; Secco, F.; Ingle, B.; Down, D.

    1980-02-01

    Over the past several years, Motorola's Materials Technology Laboratory (MTL), has been conducting several projects with goals directed at the production of high quality low cost silicon crystals. One of the projects which is being investigated is the direct purification of MG-Si. A unique characteristic of the approach used by this project is the use of a crystal puller to perform both purification and crystal growth. Sequential steps of purification were taken. By the completion of this series of purification, the purified MG-Si melt will be further purified by impurity redistribution using ingot pulling. The final purified silicon will be in an ingot form of desired dimensions for slicing into silicon sheets. The sequential steps of purification include: (1) leaching of MG-Si charge, (2) phase separation, (3) reactive gas treatment, (4) liquid-liquid extraction (called Slagging), and (5) purification by redistribution of impurities using ingot pulling. Progress on items (1) and (2) is reported. (WHK)

  11. Development of Auto-Seeding System Using Image Processing Technology in the Sapphire Crystal Growth Process via the Kyropoulos Method

    Directory of Open Access Journals (Sweden)

    Churl Min Kim

    2017-04-01

    Full Text Available The Kyropoulos (Ky and Czochralski (Cz methods of crystal growth are used for large-diameter single crystals. The seeding process in these methods must induce initial crystallization by initiating contact between the seed crystals and the surface of the melted material. In the Ky and Cz methods, the seeding process lays the foundation for ingot growth during the entire growth process. When any defect occurs in this process, it is likely to spread to the entire ingot. In this paper, a vision system was constructed for auto seeding and for observing the surface of the melt in the Ky method. An algorithm was developed to detect the time when the internal convection of the melt is stabilized by observing the shape of the spoke pattern on the melt material surface. Then, the vision system and algorithm were applied to the growth furnace, and the possibility of process automation was examined for sapphire growth. To confirm that the convection of the melt was stabilized, the position of the island (i.e., the center of a spoke pattern was detected using the vision system and image processing. When the observed coordinates for the center of the island were compared with the coordinates detected from the image processing algorithm, there was an average error of 1.87 mm (based on an image with 1024 × 768 pixels.

  12. ANALYSIS OF GROWTH OF LALAWAK Barbonymus balleroides (VALENCIENNES, 1842 IN THREE CULTURE METHODS

    Directory of Open Access Journals (Sweden)

    Deni Radona

    2017-09-01

    Full Text Available In fish culture, optimal growth could be influenced by various culture methods. Aim of the study was to evaluate the productivity of Barbonymus balleroides, lalawak in floating net cages, concrete ponds, and earthen ponds. Cultivation was designed with the circulation water system. Experiment was conducted using completely randomized design with three treatments and three replications for each treatment. The experimental fish, sized of 4.20 ± 0.64 cm SL and weight of 2.14 ± 0.99 g, were obtained from induced breeding. The stocking density used was 20 individuals/m3. Fish were fed 3% of total weight two times every day using commercial pellet with 35% protein content for 90 day. The result showed that lalawak reared in earthen pond was no significant difference on length, weight, and biomass compared with that one in concrete pond (P>0.05, but significantly different (P0.05 among the three different culture systems for survival rate and FCR. Lalawak reared on earthen pond system supported with optimal water quality could increase productivity value.

  13. Synthesis and growth mechanism of sponge-like nickel using a hydrothermal method

    Science.gov (United States)

    Shao, Bin; Yin, Xueguo; Hua, Weidong; Ma, Yilong; Sun, Jianchun; Li, Chunhong; Chen, Dengming; Guo, Donglin; Li, Kejian

    2018-05-01

    Sponge-like nickel composed of micro-chains with a diameter of 1-5 μm was selectively synthesized by the hydrothermal method, using sodium hydroxide (NaOH) as the alkaline reagent, aqueous hydrazine as reducing agent and citric acid as a coordination agent. The time-dependent samples prepared at different NaOH concentrations were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and Fourier transform infrared spectrometer (FTIR). The results showed that the agglomerates of nickel citrate hydrazine complex nanoplates were first precipitated and then reduced to prickly nickel micro-chains at a lower NaOH concentration, which played a role in the further formation of sponge-like nickel. Also, the probable growth mechanism of the sponge-like nickel was proposed. The magnetic properties of sponge-like nickel were studied using a vibrating sample magnetometer. The sponge-like nickel exhibited a ferromagnetic behavior with a saturation magnetization value of 43.8 emu g-1 and a coercivity value of 120.7 Oe.

  14. EFFECT OF SOWING DATE AND WEED CONTROL METHOD ON THE GROWTH AND YIELD OF SOYBEAN

    Directory of Open Access Journals (Sweden)

    Nasrin Akter

    2016-06-01

    Full Text Available Sowing date and weed management play a significant role in determining soybean growth, development and seed yield. Results showed that different sowing date and weed control methods had significant effect on relative weed density, weed biomass, weed control efficiency, plant height, dry weight plant-1 and seed yield of soybean. Among the infested weed species in the experimental field the dominant weeds were Lindernia procumbens (44.78%, Echinochloa colonum (26.39% and Cynodon dactylon (16.30%. The results also revealed that early sowing (2 January brought about the highest seed yield (2.17 t ha-1 and sowing delay (1 February resulted in the lowest yield (1.64 t ha-1. Two times hand weeding (20 and 40 DAS controlled the weeds most effectively and led to highest seed yield (2.23 t ha-1 which was statistically similar (2.19 t ha-1 with herbicide application. Combination effect showed that the highest seed yield (2.50 t ha-1 was obtained from 2 January sowing when the crop was weeded by hand at 20 and 40 DAS.

  15. Numerical simulation of bubble growth and departure during flow boiling period by lattice Boltzmann method

    International Nuclear Information System (INIS)

    Sun, Tao; Li, Weizhong; Yang, Shuai

    2013-01-01

    Highlights: • The bubble departure diameter is proportional to g −0.425 in quiescent fluid. • The bubble release frequency is proportional to g 0.678 in quiescent fluid. • The simulation result supports the transient micro-convection model. • The bubble departure diameter has exponential relation with inlet velocity. • The bubble release frequency has linear relation with inlet velocity. -- Abstract: Nucleate boiling flows on a horizontal plate are studied in this paper by a hybrid lattice Boltzmann method, where both quiescent and slowly flowing ambient are concerned. The process of a single bubble growth on and departure from the superheated wall is simulated. The simulation result supports the transient micro-convection model. The bubble departure diameter and the release frequency are investigated from the simulation result. It is found that the bubble departure diameter and the release frequency are proportional to g −0.425 and g 0.678 in quiescent fluid, respectively, where g is the gravitational acceleration. Nucleate boiling in slowly flowing ambient is also calculated in consideration of forced convection. It is presented that the bubble departure diameter and the release frequency have exponential relationship and linear relationship with inlet velocity in slowly flowing fluid, respectively

  16. Determination of the slow crack growth susceptibility coefficient of dental ceramics using different methods.

    Science.gov (United States)

    Gonzaga, Carla Castiglia; Cesar, Paulo Francisco; Miranda, Walter Gomes; Yoshimura, Humberto Naoyuki

    2011-11-01

    This study compared three methods for the determination of the slow crack growth susceptibility coefficient (n) of two veneering ceramics (VM7 and d.Sign), two glass-ceramics (Empress and Empress 2) and a glass-infiltrated alumina composite (In-Ceram Alumina). Discs (n = 10) were prepared according to manufacturers' recommendations and polished. The constant stress-rate test was performed at five constant stress rates to calculate n(d) . For the indentation fracture test to determine n(IF) , Vickers indentations were performed and the crack lengths were measured under an optical microscope. For the constant stress test (performed only for d.Sign for the determination of n(s) ) four constant stresses were applied and held constant until the specimens' fracture and the time to failure was recorded. All tests were performed in artificial saliva at 37°C. The n(d) values were 17.2 for Empress 2, followed by d.Sign (20.5), VM7 (26.5), Empress (30.2), and In-Ceram Alumina (31.1). In-Ceram Alumina and Empress 2 showed the highest n(IF) values, 66.0 and 40.2, respectively. The n(IF) values determined for Empress (25.2), d.Sign (25.6), and VM7 (20.1) were similar. The n(s) value determined for d.Sign was 31.4. It can be concluded that the n values determined for the dental ceramics evaluated were significantly influenced by the test method used. 2011 Wiley Periodicals, Inc.

  17. The Effect of Plant Cultivar, Growth Media, Harvest Method and Post Harvest Treatment on the Microbiology of Edible Crops

    Science.gov (United States)

    Hummerick, Mary P.; Gates, Justin R.; Nguyen, Bao-Thang; Massa, Gioia D.; Wheeler, Raymond M.

    2011-01-01

    Systems for the growth of crops in closed environments are being developed and tested for potential use in space applications to provide a source of fresh food. Plant growth conditions, growth media composition and harvest methods can have an effect on the microbial population of the plant, and therefore should be considered along with the optimization of plant growth and harvest yields to ensure a safe and palatable food crop. This work examines the effect of plant cultivar, growth media, and harvest method on plant microbial populations. Twelve varieties of leafy greens and herbs were grown on a mixture of Fafard #2 and Arcillite in the pillow root containment system currently being considered for the VEGGIE plant growth unit developed by Orbitec. In addition, ,Sierra and Outredgeous lettuce varieties were grown in three different mixtures (Fafard #2, Ardllite, and Perlite/Vermiculite). The plants were analyzed for microbial density. Two harvest methods, "cut and come again" (CACA) and terminal harvest were also compared. In one set ofexpe'riments red leaf lettuce and mizuna were grown in pots in a Biomass Production System for education. Plants were harvested every two weeks by either method. Another set of experiments was performed using the rooting pillows to grow 5 varieties of leafy greens and cut harvesting at different intervals. Radishes were harvested and replanted at two-week intervals. Results indicate up to a 3 IOglO difference in microbial counts between some varieties of plants. Rooting medium resulted in an approximately 2 IOglO lower count in the lettuce grown in arscillite then those grown in the other mixtures. Harvest method and frequency had less impact on microbial counts only showing a significant increase in one variety of plant. Post harvest methods to decrease the bacterial counts on edible crops were investigated in these and other experiments. The effectiveness of PRO-SAN and UV-C radiation is compared.

  18. Effect of solution volume covariation on the growth mechanism of Au nanorods using the seed-mediated method

    International Nuclear Information System (INIS)

    Ma, Xiao; Wang, Moo-Chin; Feng, Jinyang; Zhao, Xiujian

    2015-01-01

    The effect of solution volume covariation on the growth mechanism of Au nanorods synthesized using a seed-mediated method was studied. The results from the ultraviolet–visible absorption spectra of gold nanorods (GNRs) revealed that the transverse surface plasmon resonance was ∼550 nm for all GNR samples synthesized in various total volumes of growth solutions. The wavelength of longitudinal surface plasmon resonance of GNRs increased from 757 to 915 nm, with the total volume of growth solution being raised from 10 to 320 ml. Moreover, the calculated aspect ratio (AR) also increased from 3.55 to 5.21 while the total volume of growth solution increased from 10 to 320 ml. Transmission electron microscopy microstructures showed that the growth mechanism of GNRs along 〈1 0 0〉 is in accordance with the hypothesis that the ratio of the number of monodispersed Au atoms existing in the growth solution to the number of seeds explain the behavior of Au atoms deposited on the nanorods with respect to all of the constituent concentrations in the growth solution on the AR of GNRs

  19. Weed-crop competition effects on growth and yield of sugarcane planted using two methods

    International Nuclear Information System (INIS)

    Zafar, M.; Tanveer, A.; Cheema, Z.A.; Ashraf, M.

    2010-01-01

    Effect of planting techniques and weed-crop competition periods on yield potential of spring planted sugarcane variety HSF-240 was studied at the Ayub Agricultural Research Institute, Faisalabad, Pakistan. The experiment was laid out in RCBD with a split-plot arrangement, with four replications and net plot size of 3.6m x 10m. In the experiment, two planting techniques viz., 60 cm apart rows in flat sowing technique and 120 cm apart rows in trench sowing technique were randomized in main plots. Seven weed-crop competition periods viz., Zero (weed free), weed-crop competition for 45, 60, 75, 90, 105 days after sowing (DAS) and weedy check (full season weed-crop competition) were randomized in sub-plots. Sugarcane sown by trench method exhibited more leaf area index (LAI), average crop growth rate (ACGR) and yield contributing attributes. Trench sowing by yielding 72.22 and 75.08 t ha/sup -1/ stripped cane yields, significantly showed superiority over the flat sowing, which gave 64.13 and 66.04 t ha/sup -1/ stripped cane yields in 2005-06 and 2006- 07, respectively. Generally, there was an increase in weed population and biomass but decrease in leaf area index, crop growth rate and yield components with an increase in weed-crop competition period. A decrease of 10.06, 17.90, 22.42, 28.65, 37.64 and 56.89% in stripped cane yield was observed for weed-crop competition periods of 45, 60, 75, 90, 105 DAS and weedy check as compared with zero competition in 2005-06, respectively. In 2006-07, the respective decrease in stripped cane yield was 9.84, 18.76, 22.92, 27.98, 38.75, and 54.98%. Trench sowing at 1.2 m row spacing proved better sowing technique and 45 DAS was the critical period of weed-crop competition. (author)

  20. Development of test method for evaluating root resistance of pavement used for roof garden caused by thickening growth of root

    Energy Technology Data Exchange (ETDEWEB)

    Ishihara, Saori; Tanaka, Kyoji [Tokyo Institute of Technology, Tokyo, (Japan)

    2010-07-01

    The growth of roots of plants can damage roof garden components, such as pavements. This paper developed a test method for evaluating the resistance of pavement used in roof gardens to damage from a thickening growth of roots. The study assessed the behaviour of plant roots and evaluated the force of root growth subjected to hypertrophy. A system to measure the enlargement force of roots was designed and used for measurements over a period of 8 months on a cherry blossom of 21 years growth. The enlargement force was approximately 440 N/cm. A mechanical simulated root was designed and used to carry out experimental tests on asphalt pavements. The tests results demonstrated the viability of simulated root for evaluation of root resistances in pavements and various components of roof gardens.

  1. Statistical prediction of AVB wear growth and initiation in model F steam generator tubes using Monte Carlo method

    International Nuclear Information System (INIS)

    Lee, Jae Bong; Park, Jae Hak; Kim, Hong Deok; Chung, Han Sub; Kim, Tae Ryong

    2005-01-01

    The growth of AVB wear in Model F steam generator tubes is predicted using the Monte Carlo Method and statistical approaches. The statistical parameters that represent the characteristics of wear growth and wear initiation are derived from In-Service Inspection (ISI) Non-Destructive Evaluation (NDE) data. Based on the statistical approaches, wear growth model are proposed and applied to predict wear distribution at the End Of Cycle (EOC). Probabilistic distributions of the number of wear flaws and maximum wear depth at EOC are obtained from the analysis. Comparing the predicted EOC wear flaw data with the known EOC data the usefulness of the proposed method is examined and satisfactory results are obtained

  2. Statistical prediction of AVB wear growth and initiation in model F steam generator tubes using Monte Carlo method

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jae Bong; Park, Jae Hak [Chungbuk National Univ., Cheongju (Korea, Republic of); Kim, Hong Deok; Chung, Han Sub; Kim, Tae Ryong [Korea Electtric Power Research Institute, Daejeon (Korea, Republic of)

    2005-07-01

    The growth of AVB wear in Model F steam generator tubes is predicted using the Monte Carlo Method and statistical approaches. The statistical parameters that represent the characteristics of wear growth and wear initiation are derived from In-Service Inspection (ISI) Non-Destructive Evaluation (NDE) data. Based on the statistical approaches, wear growth model are proposed and applied to predict wear distribution at the End Of Cycle (EOC). Probabilistic distributions of the number of wear flaws and maximum wear depth at EOC are obtained from the analysis. Comparing the predicted EOC wear flaw data with the known EOC data the usefulness of the proposed method is examined and satisfactory results are obtained.

  3. [Growth of codoped CdWO4 crystals by Bridgman method and their optical spectra].

    Science.gov (United States)

    Yu, Can; Xia, Hai-Ping; Wang, Dong-Jie; Chen, Hong-Bing

    2011-09-01

    The CdWO4 crystals with good quality in the size of Phi25 mm x 120 mm, doped with Co in 0.5% molar fraction in the raw composition, were grown by the Bridgman method by taking -70 degrees C x cm(-1) of solid-liquid interface and -0.50 mm x h(-1) growth rate. The crystal presents transparence and deep blue. The X-ray diffraction (XRD) was used to characterize the crystals. Three absorption peaks at 518, 564 and 655 nm respectively, which are attributed to the overlapping of 4 T1 (4F) --> 4A2 (4F) and 4 T1 (4F) --> 4 T1 (4P) of Co2+ octahedrons, and a wide band centered at 1 863 nm, which is attributed to 4Ti (4F) --> 4 T2 (4F), was observed. The absorption results indicated that the Co ions presented +2 valence in crystal and located within the distorted oxygen octahedrons. The crystal-field parameter D(q) and the Racah parameter B were estimated to be 990 and 726.3 cm(-1) respectively based on the absorption spectra. A fluorescence emission at 778 nm (4T1 (4P) --> 4 T1 (4F)) for codoped CdWO4 crystals was observed under excitation by 520 nm light. It can be deduced from the changes in absorption and emission intensity of different parts of crystal that the concentration of Co2+ ion in crystal increased along growing direction and the effective distribution coefficient of Co2+ ion in CdWO4 crystal is less than 1.

  4. Gold nanoparticle growth control - Implementing novel wet chemistry method on silicon substrate

    KAUST Repository

    Al-Ameer, Ammar; Katsiev, Habib; Sinatra, Lutfan; Hussein, Irshad; Bakr, Osman

    2013-01-01

    Controlling particle size, shape, nucleation, and self-assembly on surfaces are some of the main challenges facing electronic device fabrication. In this work, growth of gold nanoparticles over a wide range of sizes was investigated by using a novel

  5. Test Method Variability in Slow Crack Growth Properties of Sealing Glasses

    Science.gov (United States)

    Salem, J. A.; Tandon, R.

    2010-01-01

    The crack growth properties of several sealing glasses were measured by using constant stress rate testing in 2 and 95 percent RH (relative humidity). Crack growth parameters measured in high humidity are systematically smaller (n and B) than those measured in low humidity, and crack velocities for dry environments are 100x lower than for wet environments. The crack velocity is very sensitive to small changes in RH at low RH. Biaxial and uniaxial stress states produced similar parameters. Confidence intervals on crack growth parameters that were estimated from propagation of errors solutions were comparable to those from Monte Carlo simulation. Use of scratch-like and indentation flaws produced similar crack growth parameters when residual stresses were considered.

  6. Coupled FEM-DBEM method to assess crack growth in magnet system of Wendelstein 7-X

    Directory of Open Access Journals (Sweden)

    R. Citarella

    2013-10-01

    Full Text Available The fivefold symmetric modular stellarator Wendelstein 7-X (W7-X is currently under construction in Greifswald, Germany. The superconducting coils of the magnet system are bolted onto a central support ring and interconnected with five so-called lateral support elements (LSEs per half module. After welding of the LSE hollow boxes to the coil cases, cracks were found in the vicinity of the welds that could potentially limit the allowed number N of electromagnetic (EM load cycles of the machine. In response to the appearance of first cracks during assembly, the Stress Intensity Factors (SIFs were calculated and corresponding crack growth rates of theoretical semi-circular cracks of measured sizes in potentially critical position and orientation were predicted using Paris’ law, whose parameters were calibrated in fatigue tests at cryogenic temperature. In this paper the Dual Boundary Element Method (DBEM is applied in a coupled FEM-DBEM approach to analyze the propagation of multiple cracks with different shapes. For this purpose, the crack path is assessed with the Minimum Strain Energy density criterion and SIFs are calculated by the J-integral approach. The Finite Element Method (FEM is adopted to model, using the commercial codes Ansys or Abaqus;, the overall component whereas the submodel analysis, in the volume surrounding the cracked area, is performed by FEM (“FEM-FEM approach” or alternatively by DBEM (“FEM-DBEM approach”. The “FEM-FEM approach” considers a FEM submodel, that is extracted from the FEM global model; the latter provide the boundary conditions for the submodel. Such approach is affected by some restrictions in the crack propagation phase, whereas, with the “FEM-DBEM approach”, the crack propagation simulation is straightforward. In this case the submodel is created in a DBEM environment with boundary conditions provided by the global FEM analysis; then the crack is introduced and a crack propagation analysis

  7. A non-destructive selection method for faster growth at suboptimal temperature in common bean (Phaseolus vulgaris)

    NARCIS (Netherlands)

    Drijfhout, E.; Oeveren, J.C. van; Jansen, R.C.

    1991-01-01

    A non-destructive method has been developed to select common bean (Phaseolus vulgaris L.) plants whose growth is less effected at a suboptimal temperature. Shoot weight was determined at a suboptimal (14°C) and optimal temperature (20°C), 38 days after sowing and accessions identified with a

  8. Does economic growth erode social capital and subjective well-being? Old question, new method

    OpenAIRE

    Mikucka, Malgorzata; Sarracino, Francesco; 3rd International Annual Conference of the LCSR: “Cultural and Economic changes under cross-national perspective”

    2013-01-01

    The work of Easterlin questioned the relationship between economic growth and life satisfaction. Subsequent research on “Easterlin paradox” provided conflicting evidence, which suggests that the paradox holds in some conditions but not in others. However, these conditions were only rarely investigated by the literature, in part because the debate has been limited by use of country-level aggregated data. Our paper fills this gap by investigating the relationship between economic growth and lif...

  9. How do economic growth and social capital shape subjective well-being? Old question, new method

    OpenAIRE

    Mikucka, Malgorzata; Sarracino, Francesco; The 4th LCSR International Workshop “Social and Cultural Changes in Cross-National Perspective: Values and Modernization”

    2014-01-01

    The work of Easterlin questioned the relationship between economic growth and life satisfaction. Subsequent research on “Easterlin paradox” provided conflicting evidence, which suggests that the paradox holds in some conditions but not in others. However, these conditions were only rarely investigated by the literature, in part because the debate has been limited by use of country-level aggregated data. Our paper fills this gap by investigating the relationship between economic growth and lif...

  10. Fatigue crack growth studies on a tee junction using ultrasonic non-destructive methods

    International Nuclear Information System (INIS)

    Subramanian, C.V.; Thavasimuthu, M.; Ramesh, A.S.; Jayakumar, T.; Kalyanasundaram, P.; Baldev Raj

    1996-01-01

    Fatigue cracks need to be detected and sized to maintain structural integrity. The significance of cracks detected in service must also be assessed. This paper describes the on-line ultrasonic testing carried out on a Tee joint subjected to fatigue loading. The initiation and growth of the cracks were monitored for every 5,000 cycles up to 40,000 cycles. The study demonstrated the use of ultrasonic testing for fatigue crack growth detection and sizing. (author)

  11. Improvement of elastic-plastic fatigue crack growth evaluation method. 2. Crack opening behavior

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, Yukio [Central Research Inst. of Electric Power Industry, Tokyo (Japan)

    2001-05-01

    Evaluation of crack growth behavior under cyclic loading is often required in the structural integrity assessment of cracked components. Closing and re-opening of the crack give large influence on crack growth rate through the change of fracture mechanics parameters. Based on the finite element analysis for a center-cracked plate, dependency of crack opening ratio on applied stress range and mean stress was examined. Simple formulae for representing the results were derived for plane stress and plane strain conditions. (author)

  12. Gracob: a novel graph-based constant-column biclustering method for mining growth phenotype data

    KAUST Repository

    Alzahrani, Majed A.; Kuwahara, Hiroyuki; Wang, Wei; Gao, Xin

    2017-01-01

    Growth phenotype profiling of genome-wide genedeletion strains over stress conditions can offer a clear picture that the essentiality of genes depends on environmental conditions. Systematically identifying groups of genes from such high-throughput data that share similar patterns of conditional essentiality and dispensability under various environmental conditions can elucidate how genetic interactions of the growth phenotype are regulated in response to the environment.We first demonstrate that detecting such\\co-fit

  13. Gracob: a novel graph-based constant-column biclustering method for mining growth phenotype data

    KAUST Repository

    Alzahrani, Majed A.

    2017-04-05

    Growth phenotype profiling of genome-wide genedeletion strains over stress conditions can offer a clear picture that the essentiality of genes depends on environmental conditions. Systematically identifying groups of genes from such high-throughput data that share similar patterns of conditional essentiality and dispensability under various environmental conditions can elucidate how genetic interactions of the growth phenotype are regulated in response to the environment.We first demonstrate that detecting such\\\\co-fit

  14. Method to evaluate steering and alignment algorithms for controlling emittance growth

    International Nuclear Information System (INIS)

    Adolphsen, C.; Raubenheimer, T.

    1993-04-01

    Future linear colliders will likely use sophisticated beam-based alignment and/or steering algorithms to control the growth of the beam emittance in the linac. In this paper, a mathematical framework is presented which simplifies the evaluation of the effectiveness of these algorithms. As an application, a quad alignment that uses beam data taken with the nominal linac optics, and with a scaled optics, is evaluated in terms of the dispersive emittance growth remaining after alignment

  15. A generalized diffusion model for growth of nanoparticles synthesized by colloidal methods.

    Science.gov (United States)

    Wen, Tianlong; Brush, Lucien N; Krishnan, Kannan M

    2014-04-01

    A nanoparticle growth model is developed to predict and guide the syntheses of monodisperse colloidal nanoparticles in the liquid phase. The model, without any a priori assumptions, is based on the Fick's law of diffusion, conservation of mass and the Gibbs-Thomson equation for crystal growth. In the limiting case, this model reduces to the same expression as the currently accepted model that requires the assumption of a diffusion layer around each nanoparticle. The present growth model bridges the two limiting cases of the previous model i.e. complete diffusion controlled and adsorption controlled growth of nanoparticles. Specifically, the results show that a monodispersion of nanoparticles can be obtained both with fast monomer diffusion and with surface reaction under conditions of small diffusivity to surface reaction constant ratio that results is growth 'focusing'. This comprehensive description of nanoparticle growth provides new insights and establishes the required conditions for fabricating monodisperse nanoparticles critical for a wide range of applications. Copyright © 2013 Elsevier Inc. All rights reserved.

  16. Manure placement method influenced growth, phenology and bunch yield of three Musagenotypes in a humid zone of Southern Nigeria

    OpenAIRE

    A. Tenkouano; O. O. Ndukwe; K. P. Baiyeri

    2013-01-01

    Manure placement methods earlier evaluated in a greenhouse using the banana cultivar PITA 14 as a test-crop significantly influenced root system development, vegetative growth, nutrient uptake, whole plant dry matter yield and distribution of the crop. These placement methods plus an additional treatment were re-evaluated in a field experiment over two cropping cycles using three Musa genotypes. The treatments were: a full dose of poultry manure placed on the soil surface – top dressing(T1),a...

  17. Determination of the growth restriction factor and grain size for aluminum alloys by a quasi-binary equivalent method

    International Nuclear Information System (INIS)

    Mitrašinović, A.M.; Robles Hernández, F.C.

    2012-01-01

    Highlights: ► A new method to determine the growth restricting factor. (Q) is proposed ► The proposed method is highly accurate (R 2 = 0.99) and simple. ► A major novelty of this method is the determination of Q for non-dilute samples. ► The method proposed herein is based on quasi-binary phase diagrams and composition. ► This method can be easily implemented industrially or as a research tool. - Abstract: In the present research paper is suggested a new methodology to determine the growth restricting factor (Q) and grain size (GS) for various Al-alloys. The present method combines a thermodynamical component based on the liquidus behavior of each alloying element that is later incorporated into the well known growth restricting models for multi-component alloys. This approach that can be used to determine Q and/or GS based on the chemical composition and the slope of the liquidus temperature of any Al-alloy solidified in close to equilibrium conditions. This method can be modified further in order to assess the effect of cooling rate or thermomechanical processing on growth restricting factor and grain size. In the present paper is proposed a highly accurate (R 2 = 0.99) and validated model for Al–Si alloys, but it can be modified for any other Al–X alloying system. The present method can be used for alloys with relatively high solute content and due to the use of the thermodynamics of liquidus this system considers the poisoning effects of single and multi-component alloying elements.

  18. Effect of amaranth dye on the growth and properties of conventional and SR method grown KAP single crystals

    Science.gov (United States)

    Babu Rao, G.; P., Rajesh; Ramasamy, P.

    2018-04-01

    The 0.1 mol% amaranth added KAP single crystals were grown from aqueous solutions by both slow evaporation solution technique and Sankaranarayanan-Ramasamy method. The single crystal having dimension of 45 mm length and 12 mm diameter was grown with growth rate of 1.5 mm/day using SR method. 87 % transmittance is obtained for SR method grown amaranth added KAP single crystal. The high intense luminescence at 661 nm is obtained from amaranth added conventional and SR method grown KAP single crystal. The amaranth added KAP single crystal possesses good mechanical and laser damage threshold stability.

  19. Temperature Effect Study on Growth and Survival of Pathogenic Vibrio parahaemolyticus in Jinjiang Oyster (Crassostrea rivularis with Rapid Count Method

    Directory of Open Access Journals (Sweden)

    Yuan Wang

    2018-01-01

    Full Text Available The growth of Vibrio parahaemolyticus (V. parahaemolyticus in oysters during postharvest storage increases the possibility of its infection in humans. In this work, to investigate the growth or survival profiles in different media, pathogenic V. parahaemolyticus in APW, Jinjiang oyster (JO, Crassostrea rivularis slurry, and live JO were studied under different temperatures. All the strain populations were counted through our double-layer agar plate (DLAP method. In APW, the pathogenic V. parahaemolyticus showed continuous growth under 15, 25, and 35°C, while a decline in behavior was displayed under 5°C. The similar survival trend of pathogenic V. parahaemolyticus in JO slurry and live JO was observed under 5, 25, and 35°C, except the delayed growth or decline profile compared to APW. Under 15°C, they displayed decline and growth profile in JO slurry and live JO, respectively. These results indicate the different sensitivity of pathogenic V. parahaemolyticus in these matrices to temperature variation. Furthermore, nonpathogenic V. parahaemolyticus displayed little difference in survival profiles when inoculated in live JO under corresponding temperatures. The results indicate that inhibition or promotion effect could be regulated under different storage temperature for both pathogenic and nonpathogenic strains. Besides, the DLAP method showed the obvious quickness and efficiency during the bacteria count.

  20. New Crystal-Growth Methods for Producing Lattice-Matched Substrates for High-Temperature Superconductors

    Energy Technology Data Exchange (ETDEWEB)

    Boatner, L.A.

    2008-06-24

    This effort addressed the technical problem of identifying and growing, on a commercial scale, suitable single-crystal substrates for the subsequent deposition of epitaxial thin films of high temperature semiconductors such as GaN/AlN. The lack of suitable lattice-matched substrate materials was one of the major problem areas in the development of semiconducting devices for use at elevated temperatures as well as practical opto-electronic devices based on Al- and GaN technology. Such lattice-matched substrates are necessary in order to reduce or eliminate high concentrations of defects and dislocations in GaN/AlN and related epitaxial thin films. This effort concentrated, in particular, on the growth of single crystals of ZnO for substrate applications and it built on previous ORNL experience in the chemical vapor transport growth of large single crystals of zinc oxide. This combined expertise in the substrate growth area was further complemented by the ability of G. Eres and his collaborators to deposit thin films of GaN on the subject substrates and the overall ORNL capability for characterizing the quality of such films. The research effort consisted of research on the growth of two candidate substrate materials in conjunction with concurrent research on the growth and characterization of GaN films, i.e. the effort combined bulk crystal growth capabilities in the area of substrate production at both ORNL and the industrial partner, Commercial Crystal Growth Laboratories (CCL), Naples, Florida, with the novel thin-film deposition techniques previously developed in the ORNL SSD.

  1. Ordered mesoporous silica prepared by quiescent interfacial growth method - effects of reaction chemistry

    Science.gov (United States)

    2013-01-01

    Acidic interfacial growth can provide a number of industrially important mesoporous silica morphologies including fibers, spheres, and other rich shapes. Studying the reaction chemistry under quiescent (no mixing) conditions is important for understanding and for the production of the desired shapes. The focus of this work is to understand the effect of a number of previously untested conditions: acid type (HCl, HNO3, and H2SO4), acid content, silica precursor type (TBOS and TEOS), and surfactant type (CTAB, Tween 20, and Tween 80) on the shape and structure of products formed under quiescent two-phase interfacial configuration. Results show that the quiescent growth is typically slow due to the absence of mixing. The whole process of product formation and pore structuring becomes limited by the slow interfacial diffusion of silica source. TBOS-CTAB-HCl was the typical combination to produce fibers with high order in the interfacial region. The use of other acids (HNO3 and H2SO4), a less hydrophobic silica source (TEOS), and/or a neutral surfactant (Tweens) facilitate diffusion and homogenous supply of silica source into the bulk phase and give spheres and gyroids with low mesoporous order. The results suggest two distinct regions for silica growth (interfacial region and bulk region) in which the rate of solvent evaporation and local concentration affect the speed and dimension of growth. A combined mechanism for the interfacial bulk growth of mesoporous silica under quiescent conditions is proposed. PMID:24237719

  2. Growth Factor Inhibiting PKC Sensor in E-coli Environment Using Classification Technique and ANN Method

    Directory of Open Access Journals (Sweden)

    T. K. BASAK

    2011-03-01

    Full Text Available Protein kinease C plays an important role in angiogenesis and apoptosis in cancer. During the phase of angiogenesis the growth factor is up regulated where as during apoptosis the growth factor is down regulated. For down regulation of growth factor the pH environment of intra-cellular fluid has a specific range in the alkaline medium. Protein kinease C along with E-coli through interaction of Selenometabolite is able to maintain that alkaline environment for the apoptosis of the cancer cell with inhibition of the growth factor related to antioxidant/oxidant ratio. The present paper through implementation of Artificial Neural Network and Decision Tree has focused on metastasis linked with Capacitance Relaxation phenomena and down regulation of growth factor (VGEF. In this paper a distributed neural network has been applied to a data mining problem for classification of cancer stages inorder to have proper diagnosis of patient with PKC sensor. The Network was trained off line using 270 patterns each of 6 inputs. Using the weight obtained during training, fresh patterns were tested for accuracy in diagnosis linked with the stages of cancer.

  3. Layer-by-Layer Method for the Synthesis and Growth of Surface Mounted Metal-Organic Frameworks (SURMOFs

    Directory of Open Access Journals (Sweden)

    Osama Shekhah

    2010-02-01

    Full Text Available A layer-by-layer method has been developed for the synthesis of metal-organic frameworks (MOFs and their deposition on functionalized organic surfaces. The approach is based on the sequential immersion of functionalized organic surfaces into solutions of the building blocks of the MOF, i.e., the organic ligand and the inorganic unit. The synthesis and growth of different types of MOFs on substrates with different functionalization, like COOH, OH and pyridine terminated surfaces, were studied and characterized with different surface characterization techniques. A controlled and highly oriented growth of very homogenous films was obtained using this method. The layer-by-layer method offered also the possibility to study the kinetics of film formation in more detail using surface plasmon resonance and quartz crystal microbalance. In addition, this method demonstrates the potential to synthesize new classes of MOFs not accessible by conventional methods. Finally, the controlled growth of MOF thin films is important for many applications like chemical sensors, membranes and related electrodes.

  4. Quarter elliptical crack growth using three dimensional finite element method and crack closure technique

    Energy Technology Data Exchange (ETDEWEB)

    Gozin, Mohammad-Hosein; Aghaie-Khafri, Mehrdad [K. N. Toosi University of Technology, Tehran (Korea, Republic of)

    2014-06-15

    Shape evolution of a quarter-elliptical crack emanating from a hole is studied. Three dimensional elastic-plastic finite element analysis of the fatigue crack closure was considered and the stress intensity factor was calculated based on the duplicated elastic model at each crack tip node. The crack front node was advanced proportional to the imposed effective stress intensity factor. Remeshing was applied at each step of the crack growth and solution mapping algorithm was considered. Crack growth retardation at free surfaces was successfully observed. A MATLAB-ABAQUS interference code was developed for the first time to perform crack growth on the basis of crack closure. Simulation results indicated that crack shape is sensitive to the remeshing strategy. Predictions based on the proposed models were in good agreement with Carlson's experiments results.

  5. Posttraumatic growth following a first episode of psychosis: a mixed methods research protocol using a convergent design.

    Science.gov (United States)

    Jordan, Gerald; Malla, Ashok; Iyer, Srividya N

    2016-07-25

    The suffering people experience following a first episode of psychosis is great, and has been well-investigated. Conversely, potential positive outcomes following a first episode of psychosis have been under-investigated. One such outcome that may result from a first episode of psychosis is posttraumatic growth, or a positive aftermath following the trauma of a first psychotic episode. While posttraumatic growth has been described following other physical and mental illnesses, posttraumatic growth has received very little attention following a first episode of psychosis. To address this research gap, we will conduct a mixed methods study aimed at answering two research questions: 1) How do people experience posttraumatic growth following a first episode of psychosis? 2) What predicts, or facilitates, posttraumatic growth following a first episode of psychosis? The research questions will be investigated using a mixed methods convergent design. All participants will be service-users being offered treatment for a first episode of psychosis at a specialized early intervention service for young people with psychosis, as well as their case managers.. A qualitative descriptive methodology will guide data-collection through semi-structured interviews with service-users. Service-users and case managers will complete questionnaires related to posttraumatic growth and its potential predictors using quantitative methods. These predictors include the impact a first episode of psychosis on service-users' lives, the coping strategies they use; the level of social support they enjoy; and their experiences of resilience and recovery. Qualitative data will be subject to thematic analysis, quantitative data will be subject to multiple regression analyses, and results from both methods will be combined to answer the research questions in a holistic way. Findings from this study are expected to show that in addition to suffering, people with a first episode of psychosis may experience

  6. Growth of GaN single crystals by a Ca- and Ba-added Na flux method

    Science.gov (United States)

    Ukegawa, H.; Konishi, Y.; Fujimori, T.; Miyoshi, N.; Imade, M.; Yoshimura, M.; Kitaoka, Y.; Sasaki, T.; Mori, Y.

    2011-02-01

    GaN substrates are desirable for fabricating ultra-violet LEDs and LDs, and high-power and high-frequency transistors. High-quality GaN single crystals can be obtained by using Na flux method, but the growth habit of bulk crystals must be controlled. In this study, we investigated the effects of additives (Ca, Ba) on the growth habit and impurity concentration in the crystals. The aspect ratio (c/a) of the crystals was increased by increasing the amount of additives, showing that the growth habit could be changed from the pyramidal shape to the prism shape. Ba concentration was below the detection limit (1x1015 atoms/cm3).

  7. Simple control of surface topography of gold nanoshells by a surfactant-less seeded-growth method.

    Science.gov (United States)

    Topete, Antonio; Alatorre-Meda, Manuel; Villar-Álvarez, Eva M; Cambón, Adriana; Barbosa, Silvia; Taboada, Pablo; Mosquera, Víctor

    2014-07-23

    We report the synthesis of branched gold nanoshells (BGNS) through a seeded-growth surfactant-less method. This was achieved by decorating chitosan-Pluronic F127 stabilized poly(lactic-co-gycolic) acid nanoparticles (NPs) with Au seeds (NP-seed), using chitosan as an electrostatic self-assembling agent. Branched shells with different degrees of anisotropy and optical response were obtained by modulating the ratios of HAuCl4/K2CO3 growth solution, ascorbic acid (AA) and NP-seed precursor. Chitosan and AA were crucial in determining the BGNS size and structure, acting both as coreductants and structure directing growth agents. Preliminary cytotoxicity experiments point to the biocompatibility of the obtained BGNS, allowing their potential use in biomedical applications. In particular, these nanostructures with "hybrid" compositions, which combine the features of gold nanoshells and nanostars showed a better performance as surface enhanced Raman spectroscopy probes in detecting intracellular cell components than classical smoother nanoshells.

  8. Influence of the Hydrothermal Method Growth Parameters on the Zinc Oxide Nanowires Deposited on Several Substrates

    Directory of Open Access Journals (Sweden)

    Concepción Mejía-García

    2014-01-01

    Full Text Available We report the synthesis of ZnO nanowires grown on several substrates (PET, glass, and Si using a two-step process: (a preparation of the seed layer on the substrate by spin coating, from solutions of zinc acetate dihydrate and 1-propanol, and (b growth of the ZnO nanostructures by dipping the substrate in an equimolar solution of zinc nitrate hexahydrate and hexamethylenetetramine. Subsequently, films were thermally treated with a commercial microwave oven (350 and 700 W for 5, 20, and 35 min. The ZnO nanowires obtained were characterized structurally, morphologically, and optically using XRD, SEM, and UV-VIS transmission, respectively. XRD patterns spectra revealed the presence of Zn(OH2 on the films grown on glass and Si substrates. A preferential orientation along c-axis directions for films grown on PET substrate was observed. An analysis by SEM revealed that the growth of the ZnO nanowires on PET and glass is better than the growth on Si when the same growth parameters are used. On glass substrates, ZnO nanowires less than 50 nm in diameter and between 200 nm and 1200 nm in length were obtained. The ZnO nanowires band gap energy for the films grown on PET and glass was obtained from optical transmission spectra.

  9. New improved method for evaluation of growth by food related fungi on biologically derived materials

    DEFF Research Database (Denmark)

    Bergenholtz, Karina P.; Nielsen, Per Væggemose

    2002-01-01

    Biologically derived materials, obtained as commercial and raw materials (Polylactate (PLA), Polyhydroxybutyrate (PHB), potato, wheat and corn starch) were tested for their ability to support fungal growth using a modified ASTM G21-96 (American Society for Testing and Materials) standard as well...

  10. Time dependent growth of vertically aligned carbon nanotube forest using a laser activated catalytical CVD method

    NARCIS (Netherlands)

    Haluska, M.; Bellouard, Y.J.; Dietzel, A.H.

    2008-01-01

    We report the growth of vertically aligned single-wall and multi-wall carbon nanotube forest using a Laser Activated - Catalytic Chemical Vapor Deposition process. The experiments were performed in a cold-wall reactor filled with an ethylene-hydrogen-argon gas mixture in a 5:2:8 ratio at ambient

  11. Growth of Nd doped LiNbO3 crystals using Bridgman method and its ...

    Indian Academy of Sciences (India)

    Administrator

    state for several hours so that a stable solid–liquid inter- face could ... growth would hold for about one week. ... Figure 4. The absorption spectrum of the Nd : LiNbO3 crystal. Figure 5. .... This work was supported by K C Wong Magna Fund in.

  12. Growth rates in modern speleothems from Santana Cave, Brazil, by the 210Pb-method

    International Nuclear Information System (INIS)

    Bonotto, D.M.; Karmann, I.; Baskaran, M.M.

    2012-01-01

    The Santana Cave is located at the Upper Ribeira Touristic State Park (PETAR-Parque Estadual Turístico do Alto Ribeira) in southern São Paulo State, Brazil. This paper describes 210 Pb activity concentration data in soda straw stalactites samples collected at Salão das Flores in Santana Cave that is a fossil tributary of the cave river. Non-expensive alpha counting following some analytical steps for extracting and depositing 210 Po were used for providing the 210 Pb data. In the analyzed samples, 210 Pb values of increasingly older samples fitted an exponential curve, thus suggesting that the production of 210 Pb has been constant with time. Also, the near-ideal fit indicated that the growth was uniform and there was no break in the continuous growth. The soda straw growth rates were determined from the best fit to the exponential curve through the 210 Pb activity concentration. The results of the measurements allowed estimate a longitudinal rate corresponding to 1.3 mm/yr and a lateral rate of 0.01 mm/yr, which permitted calculate times of 70 years and 317–498 years for their formation, respectively. The lateral growth rate is compatible with values from studies of chemical weathering rates held under laboratory and natural conditions.

  13. Growth of ZrSiO4 single crystal by flux method

    International Nuclear Information System (INIS)

    Ushio, Masumi; Nishitani, Yoshinari

    1982-01-01

    ZrSiO 4 single crystals were grown from the Na 2 O.3 V 2 O 5 fluxed melt at constant soaking temperatures of 900 0 C and 1000 0 C for periods up to 1710h, using the natural zircon seeds. Temperature difference between the seed and nutrient was 0.5 -- 5 0 C. A solubility curve of the natural zircon in Na 2 O.3 V 2 O 5 was determined. It was found that about 5.7g of the natural crystal dissolved in Na 2 O.3 V 2 O 5 in 48h at 1000 0 C and about 7.5g at 1200 0 C. .the maximum growth weight was about 0.35 2 g under conditions of the temperature difference of 2 0 C and the soaking for 1205h at 1000 0 C. The grown crystal was initially bounded with the c-, m-, p-, a-planes and very small planes consisting of the u- and x-, and finally bounded with the m- and p-planes. The observed linear growth rates of planes of ZrSiO 4 single crystals were in the following order:a(100) > c(001) > p(111) > m(110). The growth rates of a- and m-planes were about 5 -- 7 x 10 -4 mm/h and 0.9 -- 1.0 x 10 -4 mm/h, respectively. The growth hillocks of rounded triangular shape and elliptic shape extended to the direction of c-axis, were observed on the p- and m-planes, respectively. The observed step distence of the spiral and the step height were about 0.97 5 μm and 0.17 2 μm, respectively. The observed linear rate of advance of the step on the m-plane was about 0.4 0 -- 1.2 x 10 -8 cm/s. A linear growth rate of the m-plane was then calculated to be 0.2 5 -- 0.7 1 x 10 -4 mm/h by the BCF theory, which agreed in order of magnitude with the observes growth rate of the m-plabe. (author)

  14. Comparison between two meshless methods based on collocation technique for the numerical solution of four-species tumor growth model

    Science.gov (United States)

    Dehghan, Mehdi; Mohammadi, Vahid

    2017-03-01

    As is said in [27], the tumor-growth model is the incorporation of nutrient within the mixture as opposed to being modeled with an auxiliary reaction-diffusion equation. The formulation involves systems of highly nonlinear partial differential equations of surface effects through diffuse-interface models [27]. Simulations of this practical model using numerical methods can be applied for evaluating it. The present paper investigates the solution of the tumor growth model with meshless techniques. Meshless methods are applied based on the collocation technique which employ multiquadrics (MQ) radial basis function (RBFs) and generalized moving least squares (GMLS) procedures. The main advantages of these choices come back to the natural behavior of meshless approaches. As well as, a method based on meshless approach can be applied easily for finding the solution of partial differential equations in high-dimension using any distributions of points on regular and irregular domains. The present paper involves a time-dependent system of partial differential equations that describes four-species tumor growth model. To overcome the time variable, two procedures will be used. One of them is a semi-implicit finite difference method based on Crank-Nicolson scheme and another one is based on explicit Runge-Kutta time integration. The first case gives a linear system of algebraic equations which will be solved at each time-step. The second case will be efficient but conditionally stable. The obtained numerical results are reported to confirm the ability of these techniques for solving the two and three-dimensional tumor-growth equations.

  15. Effects of Irrigation Methods on the Growth of Petunia Grown in Heat Fusion Polyester Fiber Hardened Medium without Polythylene Pot

    OpenAIRE

    後藤, 丹十郎; 島, 浩二; 東, 千里; 森下, 照久; 藤井, 一徳; 元岡, 茂治

    2006-01-01

    Recenty, polyethylene pots(PP) present a significant environmental issue for waste disposal. To develop bedding plant production system without PP, properties of compacted medium hardened by heat fusion polyester fiber were investigated. Effects of irrigation methods on the growth of vegetative propagated petunia grown in medium without PP were investigated. The effect of medium type was not as significant as the difference in water loss per pot. Water loss per pot of medium without PP was ab...

  16. Evaluating the robustness of three ring-width measurement methods for growth release reconstruction

    Czech Academy of Sciences Publication Activity Database

    Maes, S. L.; Vannoppen, A.; Altman, Jan; Van den Bulcke, J.; Decocq, G.; De Mil, T.; Depauw, L.; Landuyt, D.; Perring, M. P.; Van Acker, J.; Vanhellemont, M.; Verheyen, K.

    2017-01-01

    Roč. 46, DEC 2017 (2017), s. 67-76 ISSN 1125-7865 R&D Projects: GA ČR(CZ) GA17-07378S; GA ČR(CZ) GA14-12262S Institutional support: RVO:67985939 Keywords : Dendrochronology * Growth release * Ring-width measurement Subject RIV: EH - Ecology, Behaviour OBOR OECD: Ecology Impact factor: 2.259, year: 2016

  17. Surface reconstruction: An effective method for the growth of mismatched materials

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Yu; Zheng, Beining; Wu, Xiaofeng; Yuan, Long; Wu, Jie; Guo, Hongping; Huang, Keke; Feng, Shouhua, E-mail: shfeng@mail.jlu.edu.cn

    2016-01-01

    Graphical abstract: High quality thin film of GaSb was fabricated with molecular beam epitaxy technique on the reconstructed Si(1 1 1) surface. - Highlights: • Surface reconstruction formed by different surface treatments controls the heteroepitaxial growth. • Mismatched stress can be effectively released when the mismatched material epi-film tilts out of the epitaxial interface plane to create a coincidence-site lattice. • GaSb films grown on Si(1 1 1)-(5√3 × 5√3)-Sb surface show better crystal quality and morphology for its self-assembled 2D fishbone structure. - Abstract: The crystalline quality of epitaxial films depends on the degree of lattice match between substrates and films. Here, we report a growth strategy for large mismatched epi-films to grow GaSb films on Si(1 1 1) substrates. The epitaxial strategy can be influenced by controlling the surface reconstructions of Sb-treated Si(1 1 1). The film with the best quality was grown on Si(1 1 1)-(5√3 × 5√3)-Sb surface due to the stress release and the formation of a self-assembled 2D fishbone structure. Controlled surface engineering provides an effective pathway towards the growth of the large mismatched materials.

  18. INVITED REVIEW: Inhibitors of myostatin as methods of enhancing muscle growth and development.

    Science.gov (United States)

    Chen, P R; Lee, K

    2016-08-01

    With the increasing demand for affordable, high-quality meat, livestock and poultry producers must continually find ways to maximize muscle growth in their animals without compromising palatability of the meat products. Muscle mass relies on myoblast proliferation during prenatal or prehatch stages and fiber hypertrophy through protein synthesis and nuclei donation by satellite cells after birth or hatch. Therefore, understanding the cellular and molecular mechanisms of myogenesis and muscle development is of great interest. Myostatin is a well-known negative regulator of muscle growth and development that inhibits proliferation and differentiation in myogenic cells as well as protein synthesis in existing muscle fibers. In this review, various inhibitors of myostatin activity or signaling are examined that may be used in animal agriculture for enhancing muscle growth. Myostatin inhibitors are relevant as potential therapies for muscle-wasting diseases and muscle weakness in humans and animals. Currently, there are no commercial myostatin inhibitors for agriculture or biomedical purposes because the safest and most effective option has yet to be identified. Further investigation of myostatin inhibitors and administration strategies may revolutionize animal production and the medical field.

  19. Comparison of manual mycobacteria growth indicator tube and epsilometer test with agar proportion method for susceptibility testing of Mycobacterium tuberculosis

    Directory of Open Access Journals (Sweden)

    N Karabulut

    2014-01-01

    Full Text Available Background and Objectives: Antimycobacterial susceptibility tests take weeks, and delayed therapy can lead to spread of Mycobacterium tuberculosis. Therefore, rapid, accurate and cost-effective methods are required for proper therapy selection. In this study, the Mycobacteria growth indicator tube (MGIT and epsilometer test (Etest methods were compared to the agar proportion method for susceptibility testing of Mycobacterium tuberculosis. Materials and Methods: The susceptibility tests against isoniazid (INH, rifampin (RIF, streptomycin (STM and ethambutol (ETM of 51 M. tuberculosis complex isolates were analyzed by the MGIT, Etest and agar proportion methods. Results: The concordance between MGIT/Etest and agar proportion methods was 98% for INH and 100% for RIF, STM, ETM. There were not statistically significant differences in results of the susceptibility tests between MGIT/Etest and the reference agar proportion method. Conclusion: The results have shown that MGIT and Etest methods can be used instead of the agar proportion method, because these two methods are more rapid and easier than the agar proportion method.

  20. Geomorphic and Structural Evidence for Rolling Hinge Style Deformation in the Footwall of an Active Low Angle Normal Fault, Mai'iu Fault, Woodlark Rift, SE Papua New Guinea

    Science.gov (United States)

    Mizera, M.; Little, T.; Norton, K. P.; Webber, S.; Ellis, S. M.; Oesterle, J.

    2016-12-01

    While shown to operate in oceanic crust, rolling hinge style deformation remains a debated process in metamorpic core complexes (MCCs) in the continents. The model predicts that unloading and isostatic uplift during slip causes a progressive back-tilting in the upper crust of a normal fault that is more steeply dipping at depth. The Mai'iu Fault in the Woodlark Rift, SE Papua New Guinea, is one of the best-exposed and fastest slipping (probably >7 mm/yr) active low-angle normal faults (LANFs) on Earth. We analysed structural field data from this fault's exhumed slip surface and footwall, together with geomorphic data interpreted from aerial photographs and GeoSAR-derived digital elevation models (gridded at 5-30 m spacing), to evaluate deformational processes affecting the rapidly exhuming, domal-shaped detachment fault. The exhumed fault surface emerges from the ground at the rangefront near sea level with a northward dip of 21°. Up-dip, it is well-preserved, smooth and corrugated, with some fault remnants extending at least 29 km in the slip direction. The surface flattens over the crest of the dome, beyond where it dips S at up to 15°. Windgaps perched on the crestal main divide of the dome, indicate both up-dip tectonic advection and progressive back-tilting of the exhuming fault surface. We infer that slip on a serial array of m-to-km scale up-to-the-north, steeply S-dipping ( 75°) antithetic-sense normal faults accommodated some of the exhumation-related, inelastic bending of the footwall. These geomorphically well expressed faults strike parallel to the main Mai'iu fault at 110.9±5°, have a mean cross-strike spacing of 1520 m, and slip with a consistent up-to-the-north sense of throw ranging from <5 m to 120 m. Apparently the Mai'iu Fault was able to continue slipping despite having to negotiate this added fault-roughness. We interpret the antithetic faulting to result from bending stresses, and to provide the first clear examples of rolling hinge

  1. Crystal growth by Bridgman and Czochralski method of the ferromagnetic quantum critical material YbNi4P2

    Science.gov (United States)

    Kliemt, K.; Krellner, C.

    2016-09-01

    The tetragonal YbNi4P2 is one of the rare examples of compounds that allow the investigation of a ferromagnetic quantum critical point. We report in detail on two different methods which have been used to grow YbNi4P2 single crystals from a self-flux. The first, a modified Bridgman method, using a closed crucible system yields needle-shaped single crystals oriented along the [001]-direction. The second method, the Czochralski growth from a levitating melt, yields large single crystals which can be cut in any desired orientation. With this crucible-free method, samples without flux inclusions and a resistivity ratio at 1.8 K of RR1.8K = 17 have been grown.

  2. Nucleation and growth of microdroplets of ionic liquids deposited by physical vapor method onto different surfaces

    Science.gov (United States)

    Costa, José C. S.; Coelho, Ana F. S. M. G.; Mendes, Adélio; Santos, Luís M. N. B. F.

    2018-01-01

    Nanoscience and technology has generated an important area of research in the field of properties and functionality of ionic liquids (ILs) based materials and their thin films. This work explores the deposition process of ILs droplets as precursors for the fabrication of thin films, by means of physical vapor deposition (PVD). It was found that the deposition (by PVD on glass, indium tin oxide, graphene/nickel and gold-coated quartz crystal surfaces) of imidazolium [C4mim][NTf2] and pyrrolidinium [C4C1Pyrr][NTf2] based ILs generates micro/nanodroplets with a shape, size distribution and surface coverage that could be controlled by the evaporation flow rate and deposition time. No indication of the formation of a wetting-layer prior to the island growth was found. Based on the time-dependent morphological analysis of the micro/nanodroplets, a simple model for the description of the nucleation process and growth of ILs droplets is presented. The proposed model is based on three main steps: minimum free area to promote nucleation; first order coalescence; second order coalescence.

  3. PIV as a method for quantifying root cell growth and particle displacement in confocal images.

    Science.gov (United States)

    Bengough, A Glyn; Hans, Joachim; Bransby, M Fraser; Valentine, Tracy A

    2010-01-01

    Particle image velocimetry (PIV) quantifies displacement of patches of pixels between successive images. We evaluated PIV as a tool for microscopists by measuring displacements of cells and of a surrounding granular medium in confocal laser scanning microscopy images of Arabidopsis thaliana roots labeled with cell-membrane targeted green fluorescent protein. Excellent accuracy (e.g., displacement standard deviation PIV-predicted and actual displacements (r(2) > 0.83). Root mean squared error for these distorted images was 0.4-1.1 pixels, increasing at higher magnification factors. Cell growth and rhizosphere deformation were tracked with good temporal (e.g., 1-min interval) and spatial resolution, with PIV patches located on recognizable cell features being tracked more successfully. Appropriate choice of GFP-label was important to decrease small-scale biological noise due to intracellular motion. PIV of roots grown in stiff 2% versus 0.7% agar showed patterns of cell expansion consistent with physically impeded roots of other species. Roots in glass ballotini underwent rapid changes in growth direction on a timescale of minutes, associated with localized arching of ballotini. By tracking cell vertices, we monitored automatically cell length, width, and area every minute for 0.5 h for cells in different stages of development. In conclusion, PIV measured displacements successfully in images of living root cells and the external granular medium, revealing much potential for use by microscopists. (c) 2009 Wiley-Liss, Inc.

  4. An effective neodimium segregation coefficient in neodimium-doped yttrium-aluminum-garnet crystal growth by pulling method

    International Nuclear Information System (INIS)

    Shiroki, Ken-ichi; Kuwano, Yasuhiko

    1978-01-01

    Effective Nd segregation coefficient in the Nd:YAG (Nd-doped Y 3 Al 5 O 12 ) crystal growth by pulling method was determined precisely over 0 -- 1.3 atom% Nd concentration range at a 0.6 mm hr -1 growth rate. Two Nd:YAG crystals (-- 20 g) were grown from a large melt (-- 1 kg). Neodymium concentrations in the crystals and residual melts were estimated by fluorescent X-ray analysis, and a value of 0.21 was obtained as the effective segregation coefficient. Next, the optical absorption coefficient of Nd:YAG crystal at 5889 A absorption peak was measured in order to analyze a small specimen for Nd by optical absorption measurements. The optical absorption coefficient of 0.97 mm -1 .atom% -1 was determined in this way. The Nd concentrations, calculated by the segregation coefficient, agreed well with those obtained by optical absorption measurements at 5889 A for six successively grown Nd:YAG crystals. Therefore, the obtained segregation coefficient, 0.21, was confirmed as a reliable value for the Nd:YAG crystal growth by the pulling method. (auth.)

  5. Method for Bacterial Growth and Ammonia Production and Effect of Inhibitory Substances in Disposable Absorbent Hygiene Products.

    Science.gov (United States)

    Forsgren-Brusk, Ulla; Yhlen, Birgitta; Blomqvist, Marie; Larsson, Peter

    The purpose of this study was to evaluate a pragmatic laboratory method to provide a technique for developing incontinence products better able to reduce malodor when used in the clinical setting. Bacterial growth and bacterially formed ammonia in disposable absorbent incontinence products was measured by adding synthetic urine inoculated with bacteria to test samples cut from the crotch area of the product. The inhibitory effect's of low pH (4.5 and 4.9) and 3 antimicrobial substances-chlorhexidine, polyhexamethylene biguanide (PHMB), and thymol-at 2 concentrations each, were studied. From the initial inocula of 3.3 log colony-forming units per milliliter (cfu/mL) at baseline, the bacterial growth of the references increased to 5.0 to 6.0 log cfu/mL at 6 hours for Escherichia coli, Proteus mirabilis, and Enterococcus faecalis. At 12 hours there was a further increase to 7.0 to 8.9 log cfu/mL. Adjusting the pH of the superabsorbent in the incontinence product from 6.0 to pH 4.5 and pH 4.9 significantly (P disposable absorbent products to inhibit bacterial growth and ammonia production. This technique, we describe, provides a pragmatic method for assessing the odor-inhibiting capacity of specific incontinence products.

  6. Nursing students' preferences of strategies surrounding cinenurducation in a first year child growth and development courses: A mixed methods study.

    Science.gov (United States)

    Oh, Jina; Steefel, Lorraine

    2016-01-01

    Use of film in the classroom (cinenurducation) promotes nursing students' motivation and understanding of concepts about child growth and development; however, consensus has not been reached regarding students' preferred strategies and what they view as effective. To identify nursing students' preferences for pedagogical strategies surrounding film use in a Child Growth and Development course. A mixed methods study encompassing a concurrent triangulation strategy was undertaken. Eighty-three students attending the first year nursing class in the fall semester 2012 at a private University in South Korea participated. Films or film clips were shown either before or after pedagogical strategies including lecture, presentation, personal essay, group report, or group discussion, followed by a questionnaire to assess student preferences and their opinions on the impact of strategies on motivation and learning. A focus group with 10 participants provided their opinions. Although the preference for the time when films were watched showed no significant difference (t=.388, p=.699), participants preferred the following pedagogical methods: watching films with a group, saying this was more effective compared to watching films alone (t=5.488, pstrategies surrounding cinenurducation helped them gain conceptual knowledge in a Child Growth and Development course. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Growth and yield of patchouli (Pogostemon cablin, Benth) due to mulching and method of fertilizer on rain-fed land

    Science.gov (United States)

    Nasruddin; Harahap, E. M.; Hanum, C.; Siregar, L. A. M.

    2018-02-01

    The drought stress that occurs during growth results in a drastic reduction in growth and yield. This study was aimed to study the effect of mulching and method of fertilizer application in reducing the impact of drought stress on patchouli plants. The experiment was conducted from July to December 2016 using a split plot design into three replications with two treatment factors. The first factor was mulch factor with three levels, i.e. M0 (without mulch), M1 (rice straw mulch) and M2 (silver black plastic mulch). The second factor was the method of fertilizer application consisting of three stages: C1 (once), C2 (twice), C3 (three times). The parameters included plant height, number of branches, number of leaves, root length, wet weight of plant, root canopy ratio, total of chlorophyll, soil temperature and soil moisture content. The results showed the use of straw mulch reduce the impact of drought stress on patchouli plants. Two times fertilizer application gave better growth and yield. The use of straw mulch produced lower temperature degrees and maintained soil moisture content.

  8. A comparison of diamond growth rate using in-liquid and conventional plasma chemical vapor deposition methods

    International Nuclear Information System (INIS)

    Takahashi, Yoshiyuki; Toyota, Hiromichi; Nomura, Shinfuku; Mukasa, Shinobu; Inoue, Toru

    2009-01-01

    In order to make high-speed deposition of diamond effective, diamond growth rates for gas-phase microwave plasma chemical vapor deposition and in-liquid microwave plasma chemical vapor deposition are compared. A mixed gas of methane and hydrogen is used as the source gas for the gas-phase deposition, and a methanol solution of ethanol is used as the source liquid for the in-liquid deposition. The experimental system pressure is in the range of 60-150 kPa. While the growth rate of diamond increases as the pressure increases, the amount of input microwave energy per unit volume of diamond is 1 kW h/mm 3 regardless of the method used. Since the in-liquid deposition method provides a superior cooling effect through the evaporation of the liquid itself, a higher electric input power can be applied to the electrodes under higher pressure environments. The growth rate of in-liquid microwave plasma chemical vapor deposition process is found to be greater than conventional gas-phase microwave plasma chemical vapor deposition process under the same pressure conditions.

  9. A comparison of diamond growth rate using in-liquid and conventional plasma chemical vapor deposition methods

    Science.gov (United States)

    Takahashi, Yoshiyuki; Toyota, Hiromichi; Nomura, Shinfuku; Mukasa, Shinobu; Inoue, Toru

    2009-06-01

    In order to make high-speed deposition of diamond effective, diamond growth rates for gas-phase microwave plasma chemical vapor deposition and in-liquid microwave plasma chemical vapor deposition are compared. A mixed gas of methane and hydrogen is used as the source gas for the gas-phase deposition, and a methanol solution of ethanol is used as the source liquid for the in-liquid deposition. The experimental system pressure is in the range of 60-150 kPa. While the growth rate of diamond increases as the pressure increases, the amount of input microwave energy per unit volume of diamond is 1 kW h/mm3 regardless of the method used. Since the in-liquid deposition method provides a superior cooling effect through the evaporation of the liquid itself, a higher electric input power can be applied to the electrodes under higher pressure environments. The growth rate of in-liquid microwave plasma chemical vapor deposition process is found to be greater than conventional gas-phase microwave plasma chemical vapor deposition process under the same pressure conditions.

  10. Synthesis of Pd@Pt Core-shell Nanoparticles based on Photochemical Seed Growth Method and Co-reduction Method and the Electrocatalytic Performance

    Directory of Open Access Journals (Sweden)

    Li Shanshan

    2016-01-01

    Full Text Available A series of Pd@Pt nanoparticles were synthesized based on electrochemical seed growth method and co-reduction method in polyethylene-glycol and acetone solution system. The TEM/HR-TEM and XPS characterization proved that the prepared composite nanoparticles present core-shell structure and analyzed the chemical state of the particles. The electrocatalytic performance of Pd@Pt particles was studied by using the electrochemical workstation. The results showed that the Pd@Pt/C catalyst of different molar ratios of Pd to Pt exhibited preferable catalytic activity and stability for the methanol catalytic oxidation reaction. Among which, the Pd@Pt nanoparticles (Pd:Pt=1:1 prepared by co-reduction method, presented highest catalytic activity, which is 2 times higher than that of Pt/C catalyst. The high catalytic activity produced by the core-shell structure was briefly discussed.

  11. Applicability of an innovative steroid-profiling method to determine synthetic growth promoter abuse in cattle

    NARCIS (Netherlands)

    Blokland, M.H.; Tricht, van E.F.; Ginkel, van L.A.; Sterk, S.S.

    2017-01-01

    A robust LC–MS/MS method was developed to quantify a large number of phase I and phase II steroids in urine. The decision limit is for most compounds lower than 1 ng ml−1 with a measurement uncertainty smaller than 30%. The method is fully validated and was applied to assess the influence of

  12. ECONOMETRIC METHODS AND MODELS USED IN THE ANALYSIS OF THE FACTORIAL INFLUENCE OF THE GROSS DOMESTIC PRODUCT GROWTH

    Directory of Open Access Journals (Sweden)

    Constantin ANGHELACHE

    2017-06-01

    Full Text Available Gross Domestic Product is the most representative synthetic indicator that expresses the evolution of the national economy. This macroeconomic indicator is used in the analysis of the level of the national economy, as well as the dynamic evolution of the national economy. In the forecast studies we rely on GDP evolution. In these situations, we might identify the factors of economic growth, and their influence. On the evolution of GDP have influence some factors: employees, labour productivity, the level of technology, investments and foreign direct investment, imports, exports or net exports, total consumption, and so on. We can analyze the data series and graphical representation. Detailed analysis is performed using econometric methods, parameters which express interdependence, meaning and intensity of correlation. Thus, we estimate the economic developments. The authors studied and proposed some econometric models for the analysis of economic growth/forecast. The novelty is that we adapt some econometric models to macroeconomic analysis.

  13. Box-scan: A novel 3DXRD method for studies of recrystallization and grain growth

    DEFF Research Database (Denmark)

    Lyckegaard, Allan; Poulsen, Henning Friis; Ludwig, Wolfgang

    2012-01-01

    Within the last decade a number of x-ray diffraction methods have been presented for non-destructive 3D characterization of polycrystalline materials. 3DXRD [1] and Diffraction Contrast Tomography [2,3,4] are examples of such methods providing full spatial and crystallographic information...... of the individual grains. Both methods rely on specially designed high-resolution near-field detectors for acquire the shape of the illuminated grains, and therefore the spatial resolution is for both methods limited by the resolution of the detector, currently ~2 micrometers. Applying these methods using...... for dynamic studies requiring high temporal resolution and set-ups involving bulky sample environments (e.g. furnaces, stress-rigs etc.)...

  14. Utilization of organic fertilizer to increase paddy growth and productivity using System of Rice Intensification (SRI method in saline soil

    Directory of Open Access Journals (Sweden)

    V . O . Subardja

    2016-01-01

    Full Text Available Soil salinity has negative effect on soil biodiversity as well as microbial activities. Hence, rice growth also effected by salinity. Application of organic fertilizer and adoption of System of Rice Intensification (SRI cultivation might improve the (biological soil properties and increase rice yield. The aim of this study was to evaluate the effect of two different rice cultivation methods namely conventional rice cultivation method and System of Rice Intensification (SRI rice cultivation method and two kinds organic fertilizer on improvement of soil biological properties and rice yield. In this study, a split plot experimental design was applied where rice cultivation method (conventional and SRI was the main plot and two kinds of organic fertilizer (market waste and rice straw was the sub plot. The treatments had four replicates. The results showed that SRI cultivation with market waste organic fertilizer could increase soil biological properties (population of microbe, fungi and soil respiration. The same treatment also increased rice growth and production. Combination of SRI and market waste organic fertilizer yielded the highest rice production (7.21 t/ha.

  15. Numerical Simulation of Yttrium Aluminum Garnet(YAG) Single Crystal Growth by Resistance Heating Czochralski(CZ) Method

    Energy Technology Data Exchange (ETDEWEB)

    You, Myeong Hyeon; Cha, Pil Ryung [Kookmin University, Seoul (Korea, Republic of)

    2017-01-15

    Yttrium Aluminum Garnet (YAG) single crystal has received much attention as the high power solid-state laser’s key component in industrial and medical applications. Various growth methods have been proposed, and currently the induction-heating Czochralski (IHCZ) growth method is mainly used to grow YAG single crystal. Due to the intrinsic properties of the IHCZ method, however, the solid/liquid interface has a downward convex shape and a sharp tip at the center, which causes a core defect and reduces productivity. To produce YAG single crystals with both excellent quality and higher yield, it is essential to control the core defects. In this study, using computer simulations we demonstrate that the resistance-heating CZ (RHCZ) method may avoid a downward convex interface and produce core defect free YAG single crystal. We studied the effects of various design parameters on the interface shape and found that there was an optimum combination of design parameter and operating conditions that produced a flat solid-liquid interface.

  16. Remote sensing change detection methods to track deforestation and growth in threatened rainforests in Madre de Dios, Peru

    Science.gov (United States)

    Shermeyer, Jacob S.; Haack, Barry N.

    2015-01-01

    Two forestry-change detection methods are described, compared, and contrasted for estimating deforestation and growth in threatened forests in southern Peru from 2000 to 2010. The methods used in this study rely on freely available data, including atmospherically corrected Landsat 5 Thematic Mapper and Moderate Resolution Imaging Spectroradiometer (MODIS) vegetation continuous fields (VCF). The two methods include a conventional supervised signature extraction method and a unique self-calibrating method called MODIS VCF guided forest/nonforest (FNF) masking. The process chain for each of these methods includes a threshold classification of MODIS VCF, training data or signature extraction, signature evaluation, k-nearest neighbor classification, analyst-guided reclassification, and postclassification image differencing to generate forest change maps. Comparisons of all methods were based on an accuracy assessment using 500 validation pixels. Results of this accuracy assessment indicate that FNF masking had a 5% higher overall accuracy and was superior to conventional supervised classification when estimating forest change. Both methods succeeded in classifying persistently forested and nonforested areas, and both had limitations when classifying forest change.

  17. Growth and characterization of magnesium chloride and lanthanum chloride doped strontium tartrate crystals - gel method

    International Nuclear Information System (INIS)

    Kalaiarasi, S.; Jaikumar, D.

    2014-01-01

    Growth of single crystals of doped strontium tartrate by controlled diffusion of strontium chloride into the silica gel charged with tartaric acid at room temperature is narrated. In this study, we synthesized magnesium chloride (5% and 10%) doped strontium tartrate crystals and Lanthanum chloride (5%, 10% and 15%) doped strontium tartrate crystals are grown. The crystal structure of the compound crystals was confirmed by single crystal X-ray diffraction. The Fourier transform infrared spectrum of pure and doped crystals are recorded and analyzed. The UV-Vis-NIR spectrum analysis reveals that the optical study of the grown crystals. The second harmonic generation efficiency was measured by using Kurtz powder technique with Nd:YAG laser of wavelength 1064 nm. (author)

  18. Development of an aptamer-based affinity purification method for vascular endothelial growth factor

    Directory of Open Access Journals (Sweden)

    Maren Lönne

    2015-12-01

    Full Text Available Since aptamers bind their targets with high affinity and specificity, they are promising alternative ligands in protein affinity purification. As aptamers are chemically synthesized oligonucleotides, they can be easily produced in large quantities regarding GMP conditions allowing their application in protein production for therapeutic purposes. Several advantages of aptamers compared to antibodies are described in general within this paper. Here, an aptamer directed against the human Vascular Endothelial Growth Factor (VEGF was used as affinity ligand for establishing a purification platform for VEGF in small scale. The aptamer was covalently immobilized on magnetic beads in a controlled orientation resulting in a functional active affinity matrix. Target binding was optimized by introduction of spacer molecules and variation of aptamer density. Further, salt-induced target elution was demonstrated as well as VEGF purification from a complex protein mixture proving the specificity of protein-aptamer binding.

  19. Thermal transport during the growth of crystalline fibers by the laser-heated float zone method

    International Nuclear Information System (INIS)

    Feigelson, R.S.

    1990-01-01

    Single crystal fibers may someday prove useful in a variety of advanced device applications. At the current time, fibers for optical, superconducting, and structural applications are under investigation. The advantage of single crystal fibers for optical devices lies in the enhanced light guiding properties one can obtain compared to a bulk crystal of the same material. Potential fiber-optic applications include optical transmission lines for remote temperature sensing and spectroscopy, solid-state lasers and amplifiers, and nonlinear devices such as harmonic generators, Raman shifters and optical parameters oscillators. In the area of superconductivity, the potential for producing long flexible fibers of the Bi 2 Sr 2 CaCu 2 O 8 high temperature superconductor which are capable of carrying high electrical current has been demonstrated. This superconductor, like other high T c materials is incongruently melting and growth rates (fiber throughput), therefore, have to be reduced to optimize the superconducting properties. Interest in single crystal fibers for structural applications stems from a strong technological interest in high strength, light weight fiber-matrix composites capable of operating at elevated temperatures. The very high crystalline perfection possible in single crystal fibers of certain materials, for example Al 2 O 3 , make them very attractive for special high temperature structural applications. Single crystal fibers are noted for having greater lower defects and hence higher strength than comparable bulk crystals. For most of the fiber applications mentioned above, stringent requirements exist for uniform diameter, homogeneous composition, and a low density of crystalline defects. Excellent growth stability is needed to obtain such fibers

  20. Kyropoulos method for growth of nonlinear optical organic crystal ABP (4-aminobenzophenone) from the melt

    Science.gov (United States)

    Pan, Shoukui; Okano, Y.; Tsunekawa, S.; Fukuda, T.

    1993-03-01

    The Kyropoulus method was used to grow nonlinear optical organic crystals ABP (4-aminobenzophenone). The crystals were characterized by nonlinear optical measurements and had a large effect of frequency doubling.

  1. Development of growth rate measuring method for intracellular, parasitic acid-fast bacteria using radioisotopes

    International Nuclear Information System (INIS)

    Nakata, Noboru; Fukutomi, Yasuo

    1998-01-01

    To prevent and treat infections diseases caused by pathogenic acid-fast bacteria such as Mycobacterium leprae, Tubercle bacillus, it is important to elucidate the mechanisms of intracellular proliferations of these bacteria. This research project was started to make DNA library using a new constructed shuttle vector. Development of in vitro evaluation method for intracellular proliferation of mycobacterium and its transformed cells was attempted on the basis of Buddemeyer method. This method was able to precisely determine the metabolic activities as low as those in leprae and its modified method using 14 C-palmitic acid was highly sensitive and the results were obtainable in a shorter period. The generated CO 2 was satisfactorily absorbed into scintillator without using a filter paper. A new culture medium from which arginine, a NO-producing compound was eliminated was used to repress the sterilizing effects of NO, but the metabolic activities of leprae was not enhanced. (M.N.)

  2. Development of growth rate measuring method for intracellular, parasitic acid-fast bacteria using radioisotopes

    Energy Technology Data Exchange (ETDEWEB)

    Nakata, Noboru; Fukutomi, Yasuo [National Inst. of Infectious Deseases, Tokyo (Japan)

    1998-02-01

    To prevent and treat infections diseases caused by pathogenic acid-fast bacteria such as Mycobacterium leprae, Tubercle bacillus, it is important to elucidate the mechanisms of intracellular proliferations of these bacteria. This research project was started to make DNA library using a new constructed shuttle vector. Development of in vitro evaluation method for intracellular proliferation of mycobacterium and its transformed cells was attempted on the basis of Buddemeyer method. This method was able to precisely determine the metabolic activities as low as those in leprae and its modified method using {sup 14}C-palmitic acid was highly sensitive and the results were obtainable in a shorter period. The generated CO{sub 2} was satisfactorily absorbed into scintillator without using a filter paper. A new culture medium from which arginine, a NO-producing compound was eliminated was used to repress the sterilizing effects of NO, but the metabolic activities of leprae was not enhanced. (M.N.)

  3. Methods to quantify soft-tissue based facial growth and treatment outcomes in children: a systematic review.

    Directory of Open Access Journals (Sweden)

    Sander Brons

    Full Text Available CONTEXT: Technological advancements have led craniofacial researchers and clinicians into the era of three-dimensional digital imaging for quantitative evaluation of craniofacial growth and treatment outcomes. OBJECTIVE: To give an overview of soft-tissue based methods for quantitative longitudinal assessment of facial dimensions in children until six years of age and to assess the reliability of these methods in studies with good methodological quality. DATA SOURCE: PubMed, EMBASE, Cochrane Library, Web of Science, Scopus and CINAHL were searched. A hand search was performed to check for additional relevant studies. STUDY SELECTION: Primary publications on facial growth and treatment outcomes in children younger than six years of age were included. DATA EXTRACTION: Independent data extraction by two observers. A quality assessment instrument was used to determine the methodological quality. Methods, used in studies with good methodological quality, were assessed for reliability expressed as the magnitude of the measurement error and the correlation coefficient between repeated measurements. RESULTS: In total, 47 studies were included describing 4 methods: 2D x-ray cephalometry; 2D photography; anthropometry; 3D imaging techniques (surface laser scanning, stereophotogrammetry and cone beam computed tomography. In general the measurement error was below 1 mm and 1° and correlation coefficients range from 0.65 to 1.0. CONCLUSION: Various methods have shown to be reliable. However, at present stereophotogrammetry seems to be the best 3D method for quantitative longitudinal assessment of facial dimensions in children until six years of age due to its millisecond fast image capture, archival capabilities, high resolution and no exposure to ionizing radiation.

  4. Influence of the growth parameters on TiO2 thin films deposited using the MOCVD method

    Directory of Open Access Journals (Sweden)

    Bernardi M. I. B.

    2002-01-01

    Full Text Available In this work we report the synthesis of TiO2 thin films by the Organometallic Chemical Vapor Deposition (MOCVD method. The influence of deposition parameters used during the growth in the obtained structural characteristics was studied. Different temperatures of the organometallic bath, deposition time, temperature and type of the substrate were combined. Using Scanning Electron Microscopy associated to Electron Dispersive X-Ray Spectroscopy, Atomic Force Microscopy and X-ray Diffraction, the strong influence of these parameters in the thin films final microstructure was verified.

  5. Effects of different soil remediation methods on inhibition of lead absorption and growth and quality of Dianthus superbus L.

    Science.gov (United States)

    Yang, Xiaoyu; Ma, Siyue; Li, Jianheng

    2017-12-01

    Heavy metal pollution in soil poses a serious threat to the growth of plants used in traditional Chinese medicine. Therefore, a pot experiment was conducted to study the effects of various soil remediation methods on the performance of Herba Dianthi (Dianthus superbus L.) grown on Pb-contaminated soil. The results show that inoculation of Herba Dianthi with arbuscular mycorrhizal fungi (AMF) led to a significant reduction in Pb uptake (P< 0.05), and increased root development and root-to-shoot ratio compared to untreated control plants, along with the highest content of active components. When planting with Trifolium repens, the reduction effect of Pb absorption was insignificant. Herba Dianthi showed improved growth and active ingredients, and the lowest Pb content, with AMF inoculation. The addition of EDTA decreased the growth of Herba Dianthi, but promoted the absorption of Pb. The inhibition of tumor cells was highest in E2. In conclusion, inoculation with AMF can ensure that plant lead content meets testing standards, helping to improve the quality of medicinal herbs.

  6. A kinetic Monte Carlo simulation method of van der Waals epitaxy for atomistic nucleation-growth processes of transition metal dichalcogenides.

    Science.gov (United States)

    Nie, Yifan; Liang, Chaoping; Cha, Pil-Ryung; Colombo, Luigi; Wallace, Robert M; Cho, Kyeongjae

    2017-06-07

    Controlled growth of crystalline solids is critical for device applications, and atomistic modeling methods have been developed for bulk crystalline solids. Kinetic Monte Carlo (KMC) simulation method provides detailed atomic scale processes during a solid growth over realistic time scales, but its application to the growth modeling of van der Waals (vdW) heterostructures has not yet been developed. Specifically, the growth of single-layered transition metal dichalcogenides (TMDs) is currently facing tremendous challenges, and a detailed understanding based on KMC simulations would provide critical guidance to enable controlled growth of vdW heterostructures. In this work, a KMC simulation method is developed for the growth modeling on the vdW epitaxy of TMDs. The KMC method has introduced full material parameters for TMDs in bottom-up synthesis: metal and chalcogen adsorption/desorption/diffusion on substrate and grown TMD surface, TMD stacking sequence, chalcogen/metal ratio, flake edge diffusion and vacancy diffusion. The KMC processes result in multiple kinetic behaviors associated with various growth behaviors observed in experiments. Different phenomena observed during vdW epitaxy process are analysed in terms of complex competitions among multiple kinetic processes. The KMC method is used in the investigation and prediction of growth mechanisms, which provide qualitative suggestions to guide experimental study.

  7. Modelling the growth of ZnO thin films by PVD methods and the effects of post-annealing.

    Science.gov (United States)

    Blackwell, Sabrina; Smith, Roger; Kenny, Steven D; Walls, John M; Sanz-Navarro, Carlos F

    2013-04-03

    Results are presented for modelling of the evaporation and magnetron sputter deposition of Zn(x)O(y) onto an O-terminated ZnO (0001¯) wurtzite surface. Growth was simulated through a combination of molecular dynamics (MD) and an on-the-fly kinetic Monte Carlo (otf-KMC) method, which finds diffusion pathways and barriers without prior knowledge of transitions. We examine the effects of varying experimental parameters, such as substrate bias, distribution of the deposition species and annealing temperature. It was found when comparing evaporation and sputtering growth that the latter process results in a denser and more crystalline structure, due to the higher deposition energy of the arriving species. The evaporation growth also exhibits more stacking faults than the sputtered growth. Post-annealing at 770 K did not allow complete recrystallization, resulting in films which still had stacking faults where monolayers formed in the zinc blende phase, whereas annealing at 920 K enabled the complete recrystallization of some films to the wurtzite structure. At the latter temperature atoms could also sometimes be locked in the zinc blende phase after annealing. When full recrystallization did not take place, both wurtzite and zinc blende phases were seen in the same layer, resulting in a phase boundary. Investigation of the various distributions of deposition species showed that, during evaporation, the best quality film resulted from a stoichiometric distribution where only ZnO clusters were deposited. During sputtering, however, the best quality film resulted from a slightly O rich distribution. Two stoichiometric distributions, one involving mainly ZnO clusters and the other involving mainly single species, showed that the distribution of deposition species makes a huge impact on the grown film. The deposition of predominantly single species causes many more O atoms at the surface to be sputtered or reflected, resulting in an O deficiency of up to 18% in the

  8. Logging costs and cutting methods in young-growth ponderosa pine in California

    Science.gov (United States)

    Philip M. McDonald; William A. Atkinson; Dale O. Hall

    1969-01-01

    Mixed-conifer stands at the Challenge Experimental Forest, Calif., were cut to four specifications: seed-tree, group selection, single tree selection, and clearcut. Logging costs and production rates were compared and evaluated. Cutting method had little effect on felling or skidding production; felling ranged from 1,802 to 2,019 bd ft per hour, and skidding from 3,138...

  9. Instructors' Growth in TPACK: Teaching Technology-Infused Methods Courses to Preservice Teachers

    Science.gov (United States)

    Foulger, Teresa S.; Buss, Ray R.; Wetzel, Keith; Lindsey, LeeAnn

    2015-01-01

    We were concerned about teaching a stand-alone technology integration course while advocating that teachers employ full integration. Our college moved to a tech-infusion model whereby our educational technology curriculum would be incorporated in methods courses. Using a qualitative approach, we documented experiences of teacher educators who were…

  10. An efficient and reproducible method for improving growth of a soil alga (Chlorococcum infusionum) for toxicity assays.

    Science.gov (United States)

    Nam, Sun-Hwa; An, Youn-Joo

    2015-12-01

    This study evaluated five methods of soil inoculation using the soil alga Chlorococcum infusionum to determine the most efficient and reproducible method for promoting the growth of soil algae for toxicity testing. The five techniques included application of C. infusionum in a circle on top of the soil, to a central spot on top of the soil, to a central spot in the subsoil, to one side on top of the soil, and application divided between a circle and a central spot on top of the soil. Of these, the first method generated the greatest amount of chlorophyll fluorescence and was the method with the best reproducibility. We evaluated the applicability of this method in an assessment of the toxicity of copper and nickel to C. infusionum in two representative standard soils. Copper (20-75 mg/kg for OECD soil and 20-60 mg/kg Lufa 2.2 soil) and nickel (400-500 mg/kg for OECD soil and 60-100 mg/kg Lufa 2.2 soil) reduced the chlorophyll fluorescence of C. infusionum when the inoculation was delivered in a circle on top of both soil types. To our knowledge, this is the first study to assess the suitability of different soil algal inoculation methods for terrestrial toxicity testing. Copyright © 2015 Elsevier B.V. All rights reserved.

  11. Low temperature and self catalytic growth of ultrafine ITO nanowires by electron beam evaporation method and their optical and electrical properties

    International Nuclear Information System (INIS)

    Kumar, R. Rakesh; Rao, K. Narasimha; Rajanna, K.; Phani, A.R.

    2014-01-01

    Highlights: • ITO nanowires were grown by e-beam evaporation method. • ITO nanowires growth done at low substrate temperature of 350 °C. • Nanowires growth was carried out without use of catalyst and reactive oxygen gas. • Nanowires growth proceeds via self catalytic VLS growth. • Grown nanowires have diameter 10–20 nm and length 1–4 μm long. • ITO nanowire films have shown good antireflection property. - Abstract: We report the self catalytic growth of Sn-doped indium oxide (ITO) nanowires (NWs) over a large area glass and silicon substrates by electron beam evaporation method at low substrate temperatures of 250–400 °C. The ITO NWs growth was carried out without using an additional reactive oxygen gas and a metal catalyst particle. Ultrafine diameter (∼10–15 nm) and micron long ITO NWs growth was observed in a temperature window of 300–400 °C. Transmission electron microscope studies confirmed single crystalline nature of the NWs and energy dispersive spectroscopy studies on the NWs confirmed that the NWs growth proceeds via self catalytic vapor-liquid-solid (VLS) growth mechanism. ITO nanowire films grown on glass substrates at a substrate temperature of 300–400 °C have shown ∼2–6% reflection and ∼70–85% transmission in the visible region. Effect of deposition parameters was systematically investigated. The large area growth of ITO nanowire films would find potential applications in the optoelectronic devices

  12. Coarse-graining and hybrid methods for efficient simulation of stochastic multi-scale models of tumour growth

    International Nuclear Information System (INIS)

    Cruz, Roberto de la; Guerrero, Pilar; Calvo, Juan; Alarcón, Tomás

    2017-01-01

    The development of hybrid methodologies is of current interest in both multi-scale modelling and stochastic reaction–diffusion systems regarding their applications to biology. We formulate a hybrid method for stochastic multi-scale models of cells populations that extends the remit of existing hybrid methods for reaction–diffusion systems. Such method is developed for a stochastic multi-scale model of tumour growth, i.e. population-dynamical models which account for the effects of intrinsic noise affecting both the number of cells and the intracellular dynamics. In order to formulate this method, we develop a coarse-grained approximation for both the full stochastic model and its mean-field limit. Such approximation involves averaging out the age-structure (which accounts for the multi-scale nature of the model) by assuming that the age distribution of the population settles onto equilibrium very fast. We then couple the coarse-grained mean-field model to the full stochastic multi-scale model. By doing so, within the mean-field region, we are neglecting noise in both cell numbers (population) and their birth rates (structure). This implies that, in addition to the issues that arise in stochastic-reaction diffusion systems, we need to account for the age-structure of the population when attempting to couple both descriptions. We exploit our coarse-graining model so that, within the mean-field region, the age-distribution is in equilibrium and we know its explicit form. This allows us to couple both domains consistently, as upon transference of cells from the mean-field to the stochastic region, we sample the equilibrium age distribution. Furthermore, our method allows us to investigate the effects of intracellular noise, i.e. fluctuations of the birth rate, on collective properties such as travelling wave velocity. We show that the combination of population and birth-rate noise gives rise to large fluctuations of the birth rate in the region at the leading edge

  13. Cu diffusion as an alternative method for nanopatterned CuTCNQ film growth

    International Nuclear Information System (INIS)

    Capitán, M J; Álvarez, J; Miranda, R; Navío, C

    2016-01-01

    In this paper we show by means of ‘in situ’ x-ray diffraction studies that CuTCNQ formation from Cu(solid)–TCNQ(solid tetracyanoquinodimethane) goes through Cu diffusion at room temperature. The film quality depends on the TCNQ evaporation rate. At low evaporation rate we get a single phase-I CuTCNQ film very well crystallized and well oriented. The film has a CuTCNQ(0 2 0) orientation. The film is formed by CuTCNQ nanorods of a very homogeneous size. The film homogeneity has also been seen by atomic force microscopy (AFM). The electronic properties of the film have been measured by x-ray photoelectron spectroscopy (XPS) and ultra-violet photoelectron spectroscopy (UPS). Thus, the Cu-diffusion method has arisen as a very simple, clean and efficient method to grow localized CuTCNQ nanorods on Cu, opening up new insights for technological applications. (paper)

  14. Growth of Bi 12SiO 20 single crystals by the pulling-down method with continuous feeding

    Science.gov (United States)

    Maida, Shigeru; Higuchi, Mikio; Kodaira, Kohei

    1999-09-01

    Bi 12SiO 20 single crystals were successfully grown by the pulling-down method with continuous feeding. As-grown crystals were amber in color and transparent, and had no cracks or inclusions. A crystal with homogeneous composition was obtained from Bi-rich feed powder having a composition of 14.1 mol% SiO 2, whereas precipitates of Bi 4Si 3O 12 were observed on the surface of a crystal grown with stoichiometric powder. The shape of the solid-liquid interface during the crystal growth was estimated to be almost flat, which was favorable to avoid core formation. Average dislocation density was 4×10 3/cm 2, which was comparable to that of Bi 12SiO 20 crystals grown by the Czochralski method.

  15. Moderating effect of ammonia on particle growth and stability of quasi-monodisperse silver nanoparticles synthesized by the Turkevich method.

    Science.gov (United States)

    Gorup, Luiz F; Longo, Elson; Leite, Edson R; Camargo, Emerson R

    2011-08-15

    A new method to stabilize silver nanoparticles by the addition of ammonia is proposed. Colloidal dispersions of silver nanoparticles were synthesized by the Turkevich method using sodium citrate to reduce silver nitrate at high pH and at 90 °C. After approximately 12 min, a diluted ammonia solution was added to the reaction flask to form soluble diamine silver (I) complexes that played an important growth moderating role, making it possible to stabilize metallic silver nanoparticles with sizes as small as 1.6 nm after 17 min of reaction. Colloidal dispersions were characterized by UV-visible absorption spectroscopy, X-ray diffraction, and transmission electronic microscopy. Copyright © 2011 Elsevier Inc. All rights reserved.

  16. Oriented growth of magnetite along the carbon nanotubes via covalently bonded method in a simple solvothermal system

    Energy Technology Data Exchange (ETDEWEB)

    Zhan Yingqing; Zhao Rui; Meng Fanbing; Lei Yajie; Zhong Jiachun; Yang Xulin [Research Branch of Functional Materials, Institute of Microelectronic and Solid State Electronic, University of Electronic Science and Technology of China, Chengdu 610054 (China); Liu Xiaobo, E-mail: liuxb@uestc.edu.cn [Research Branch of Functional Materials, Institute of Microelectronic and Solid State Electronic, University of Electronic Science and Technology of China, Chengdu 610054 (China)

    2011-06-15

    Highlights: > Novel CNTs/magnetite hybrid materials were prepared via covalently bonded method. > Stable interaction between nitriles and iron ion promoted the oriented growth of magnetite. > The hybrid material exhibited higher magnetism and electromagnetic properties - Abstract: A new type of CNTs/magnetite hybrid material was prepared via covalently bonded method in a simple solvothermal system using FeCl{sub 3} as iron source, ethylene glycol as the reducing agent, and 4-aminophenoxyphthalonitrile-grafted CNTs as templates. The magnetite nanoparticles, with the diameters of 70-80 nm, were self-assembled along the CNTs. The FTIR, UV-vis and DSC revealed that a stable covalent bond between nitriles group and iron ion promoted the oriented growth of magnetite nanoparticles along the CNTs, resulting in good dispersibility and solution storage stability. The magnetic properties measurements indicated that a higher saturated magnetization (70.7 emu g{sup -1}) existed in the CNTs/magnetite hybrid material, which further enhanced the electromagnetic properties. The magnetic loss was caused mainly by natural resonance, which is in good agreement with the Kittel equation results. The novel electromagnetic hybrid material is believed to have potential applications in the microwave absorbing performances.

  17. Oriented growth of magnetite along the carbon nanotubes via covalently bonded method in a simple solvothermal system

    International Nuclear Information System (INIS)

    Zhan Yingqing; Zhao Rui; Meng Fanbing; Lei Yajie; Zhong Jiachun; Yang Xulin; Liu Xiaobo

    2011-01-01

    Highlights: → Novel CNTs/magnetite hybrid materials were prepared via covalently bonded method. → Stable interaction between nitriles and iron ion promoted the oriented growth of magnetite. → The hybrid material exhibited higher magnetism and electromagnetic properties - Abstract: A new type of CNTs/magnetite hybrid material was prepared via covalently bonded method in a simple solvothermal system using FeCl 3 as iron source, ethylene glycol as the reducing agent, and 4-aminophenoxyphthalonitrile-grafted CNTs as templates. The magnetite nanoparticles, with the diameters of 70-80 nm, were self-assembled along the CNTs. The FTIR, UV-vis and DSC revealed that a stable covalent bond between nitriles group and iron ion promoted the oriented growth of magnetite nanoparticles along the CNTs, resulting in good dispersibility and solution storage stability. The magnetic properties measurements indicated that a higher saturated magnetization (70.7 emu g -1 ) existed in the CNTs/magnetite hybrid material, which further enhanced the electromagnetic properties. The magnetic loss was caused mainly by natural resonance, which is in good agreement with the Kittel equation results. The novel electromagnetic hybrid material is believed to have potential applications in the microwave absorbing performances.

  18. Numerical simulation of flow and mass transfer for large KDP crystal growth via solution-jet method

    Science.gov (United States)

    Yin, Huawei; Li, Mingwei; Hu, Zhitao; Zhou, Chuan; Li, Zhiwei

    2018-06-01

    A novel technique of growing large crystals of potassium dihydrogen phosphate (KDP) named solution-jet method is proposed. The aim is to increase supersaturation on the pyramidal face, especially for crystal surface regions close to the rotation axis. The fluid flow and surface supersaturation distribution of crystals grown under different conditions were computed using the finite-volume method. Results indicate that the time-averaged supersaturation of the pyramidal face in the proposed method significantly increases and the supersaturation difference from the crystal center to edge clearly decreases compared with the rotating-crystal method. With increased jet velocity, supersaturation on the pyramidal face steadily increases. Rotation rate considerably affects the magnitude and distribution of the prismatic surface supersaturation. With increased crystal size, the mean value of surface supersaturation averaged over the pyramid gradually decreases; conversely, standard deviation increases, which is detrimental to crystal growth. Moreover, the significant roles played by natural and forced convection in the process of mass transport are discussed. Results show that further increased jet velocity to 0.6 m/s renders negligible the effects of natural convection around the pyramid. The simulation for step propagation indicates that solution-jet method can promote a steady step migration and enhance surface morphology stability, which can improve the crystal quality.

  19. Growth and Characterization of Indium Doped ZnO Nano wires Using Thermal Evaporation Method

    International Nuclear Information System (INIS)

    Abrar Ismardi; Dee, C.F.; Majlis, B.Y.

    2011-01-01

    Indium doped ZnO nano wires were grown on silicon substrate using vapor thermal deposition method without using any catalyst. Morphological structures were extensively investigated using field emission scanning electron microscopy (FESEM) and show that the nano wires have uniformly hexagonal nano structures with diameters less than 100 nm and lengths from one to a few microns. The sample was measured for elemental composition with energy dispersive X-ray (EDX) spectroscopy, Zn, In and O elements were found on the sample. XRD spectrum of indium doped ZnO nano wires revealed that the nano wires have a high crystalline structure. (author)

  20. Modelling and Simulation of Photosynthetic Microorganism Growth: Random Walk vs. Finite Difference Method

    Czech Academy of Sciences Publication Activity Database

    Papáček, Š.; Matonoha, Ctirad; Štumbauer, V.; Štys, D.

    2012-01-01

    Roč. 82, č. 10 (2012), s. 2022-2032 ISSN 0378-4754. [Modelling 2009. IMACS Conference on Mathematical Modelling and Computational Methods in Applied Sciences and Engineering /4./. Rožnov pod Radhoštěm, 22.06.2009-26.06.2009] Grant - others:CENAKVA(CZ) CZ.1.05/2.1.00/01.0024; GA JU(CZ) 152//2010/Z Institutional research plan: CEZ:AV0Z10300504 Keywords : multiscale modelling * distributed parameter system * boundary value problem * random walk * photosynthetic factory Subject RIV: EI - Biotechnology ; Bionics Impact factor: 0.836, year: 2012

  1. [Selecting methods and awaiting growth: the teaching experience of fundamental nursing practicum instructors].

    Science.gov (United States)

    Lin, Hui-Chen; Lin, Chi-Yi; Chien, Tsui-Wei; Liu, Kuei-Fen; Chen, Miao-Yen; Lin, Wen-Chuan

    2013-02-01

    A constellation of factors accounts for teaching efficacy in the fundamental nursing practicum. Teachers play a critical role in terms of designing and executing an appropriate teaching plan, choosing effective methods, and holding appropriate teaching attitudes. It is thus extremely important that clinical teachers master the core characteristics of basic nursing practice. This study aimed to illuminate the core characteristics of basic nursing practice for students for reference by clinical practicum teachers. Qualitative research was used to identify the fundamentals of nursing practice by clinical teacher. Five focus group meetings were convened during the practice period. The researchers presided over group discussions held during the normal weekly teaching schedule and lasting approximately 2-4 hours each. The content analysis was adopted to analyze the data. Three major themes were proposed, including (1) student status: "novices were stymied by problems and thus improved slowly"; (2) teacher awareness: "teachers need to be aware of student capabilities, mood, and discomfort"; and (3) teaching style: "a good choice of methods should support and encourage students. To cultivate professional nursing knowledge and self-confidence for future professional commitment, clinical teachers must first understand the characteristics and motivations of learning of their students and then select the, skills, and attitudes appropriate to provide step-by-step guidance. Communication with staffs and the preparation of atmosphere prior to nursing practice are also essential for students. Results provide insights into the technical college environment with regard to basic-level clinical nursing practice.

  2. Water-assisted growth of graphene on carbon nanotubes by the chemical vapor deposition method.

    Science.gov (United States)

    Feng, Jian-Min; Dai, Ye-Jing

    2013-05-21

    Combining carbon nanotubes (CNTs) with graphene has been proved to be a feasible method for improving the performance of graphene for some practical applications. This paper reports a water-assisted route to grow graphene on CNTs from ferrocene and thiophene dissolved in ethanol by the chemical vapor deposition method in an argon flow. A double injection technique was used to separately inject ethanol solution and water for the preparation of graphene/CNTs. First, CNTs were prepared from ethanol solution and water. The injection of ethanol solution was suspended and water alone was injected into the reactor to etch the CNTs. Thereafter, ethanol solution was injected along with water, which is the key factor in obtaining graphene/CNTs. Transmission electron microscopy, scanning electron microscopy, X-ray diffraction, and Raman scattering analyses confirmed that the products were the hybrid materials of graphene/CNTs. X-ray photo-electron spectroscopy analysis showed the presence of oxygen rich functional groups on the surface of the graphene/CNTs. Given the activity of the graphene/CNT surface, CdS quantum dots adhered onto it uniformly through simple mechanical mixing.

  3. Numerical approximations for the molecular beam epitaxial growth model based on the invariant energy quadratization method

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Xiaofeng, E-mail: xfyang@math.sc.edu [Department of Mathematics, University of South Carolina, Columbia, SC 29208 (United States); Zhao, Jia, E-mail: zhao62@math.sc.edu [Department of Mathematics, University of South Carolina, Columbia, SC 29208 (United States); Department of Mathematics, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599 (United States); Wang, Qi, E-mail: qwang@math.sc.edu [Department of Mathematics, University of South Carolina, Columbia, SC 29208 (United States); Beijing Computational Science Research Center, Beijing (China); School of Materials Science and Engineering, Nankai University, Tianjin (China)

    2017-03-15

    The Molecular Beam Epitaxial model is derived from the variation of a free energy, that consists of either a fourth order Ginzburg–Landau double well potential or a nonlinear logarithmic potential in terms of the gradient of a height function. One challenge in solving the MBE model numerically is how to develop proper temporal discretization for the nonlinear terms in order to preserve energy stability at the time-discrete level. In this paper, we resolve this issue by developing a first and second order time-stepping scheme based on the “Invariant Energy Quadratization” (IEQ) method. The novelty is that all nonlinear terms are treated semi-explicitly, and the resulted semi-discrete equations form a linear system at each time step. Moreover, the linear operator is symmetric positive definite and thus can be solved efficiently. We then prove that all proposed schemes are unconditionally energy stable. The semi-discrete schemes are further discretized in space using finite difference methods and implemented on GPUs for high-performance computing. Various 2D and 3D numerical examples are presented to demonstrate stability and accuracy of the proposed schemes.

  4. TiO2 thin film growth using the MOCVD method

    Directory of Open Access Journals (Sweden)

    Bernardi M.I.B.

    2001-01-01

    Full Text Available Titanium oxide (TiO2 thin films were obtained using the MOCVD method. In this report we discuss the properties of a film, produced using a ordinary deposition apparatus, as a function of the deposition time, with constant deposition temperature (90 °C, oxygen flow (7,0 L/min and substrate temperature (400 °C. The films were characterized by X-ray diffraction (XRD, scanning electron microscopy (SEM, atomic force microscopy (AFM and visible and ultra-violet region spectroscopy (UV-Vis. The films deposited on Si (100 substrates showed the anatase polycrystalline phase, while the films grown on glass substrates showed no crystallinity. Film thickness increased with deposition time as expected, while the transmittance varied from 72 to 91% and the refractive index remained close to 2.6.

  5. Few-layer graphene growth from polystyrene as solid carbon source utilizing simple APCVD method

    Science.gov (United States)

    Ahmadi, Shahrokh; Afzalzadeh, Reza

    2016-07-01

    This research article presents development of an economical, simple, immune and environment friendly process to grow few-layer graphene by controlling evaporation rate of polystyrene on copper foil as catalyst and substrate utilizing atmospheric pressure chemical vapor deposition (APCVD) method. Evaporation rate of polystyrene depends on molecular structure, amount of used material and temperature. We have found controlling rate of evaporation of polystyrene by controlling the source temperature is easier than controlling the material weight. Atomic force microscopy (AFM) as well as Raman Spectroscopy has been used for characterization of the layers. The frequency of G‧ to G band ratio intensity in some samples varied between 0.8 and 1.6 corresponding to few-layer graphene. Topography characterization by atomic force microscopy confirmed Raman results.

  6. Evaluation of a Mobile Application for Multiplier Method Growth and Epiphysiodesis Timing Predictions.

    Science.gov (United States)

    Wagner, Pablo; Standard, Shawn C; Herzenberg, John E

    The multiplier method (MM) is frequently used to predict limb-length discrepancy and timing of epiphysiodesis. The traditional MM uses complex formulae and requires a calculator. A mobile application was developed in an attempt to simplify and streamline these calculations. We compared the accuracy and speed of using the traditional pencil and paper technique with that using the Multiplier App (MA). After attending a training lecture and a hands-on workshop on the MM and MA, 30 resident surgeons were asked to apply the traditional MM and the MA at different weeks of their rotations. They were randomized as to the method they applied first. Subjects performed calculations for 5 clinical exercises that involved congenital and developmental limb-length discrepancies and timing of epiphysiodesis. The amount of time required to complete the exercises and the accuracy of the answers were evaluated for each subject. The test subjects answered 60% of the questions correctly using the traditional MM and 80% of the questions correctly using the MA (P=0.001). The average amount of time to complete the 5 exercises with the MM and MA was 22 and 8 minutes, respectively (P<0.0001). Several reports state that the traditional MM is quick and easy to use. Nevertheless, even in the most experienced hands, performing the calculations in clinical practice can be time-consuming. Errors may result from choosing the wrong formulae and from performing the calculations by hand. Our data show that the MA is simpler, more accurate, and faster than the traditional MM from a practical standpoint. Level II.

  7. Statistical modelling and RCS detrending methods provide similar estimates of long-term trend in radial growth of common beech in north-eastern France

    OpenAIRE

    Bontemps , Jean-Daniel; Esper , Jan

    2011-01-01

    International audience; Dendrochronological methods have greatly contributed to the documentation of past long-term trends in forest growth. These methods primarily focus on the high-frequency signals of tree ring chronologies. They require the removal of the ageing trend in tree growth, known as 'standardisation' or 'detrending', as a prerequisite to the estimation of such trends. Because the approach is sequential, it may however absorb part of the low-frequency historical signal. In this s...

  8. Modifications of micro-pulling-down method for the growth of selected Li-containing crystals for neutron scintillator and VUV scintillation crystals

    Science.gov (United States)

    Pejchal, J.; Fujimoto, Y.; Chani, V.; Yanagida, T.; Yokota, Y.; Yoshikawa, A.; Nikl, M.; Beitlerova, A.

    2012-12-01

    To develop new and efficient neutron scintillator, Ti-doped LiAlO2 single crystal was grown by micro-pulling-down method. The X-ray excited radioluminescence spectra and neutron light yield were measured. Positive effect of Mg codoping on the overall scintillation efficiency was found. The BaLu2F8 single crystal was grown by micro-pulling-down method using low temperature gradient at growth interface and applying quenching immediately after growth process.

  9. Application of a data reconciliation method to the stoichiometric analysis of Fibrobacter succinogenes growth.

    Science.gov (United States)

    Guiavarch, Erell; Pons, Agnes; Creuly, Catherine; Dussap, Claude-Gilles

    2008-12-01

    Fibrobacter succinogenes S85, a strictly anaerobic Gram-negative bacterium, was grown in continuous culture in a bioreactor at different dilution rates (0.02 to 0.092 h(-1)) on a fully synthetic culture medium with glucose as carbon source. Glucose and ammonium sulfate consumption, as well as biomass, succinate, acetate, formate, and carbohydrate production were regularly measured. The relevant biomass elemental compositions were established for each dilution rate. Robustness of the experimental information was checked by C and N mass balances estimation, which were satisfactory. A detailed overall stoichiometry analysis of the process, including all substrates and products of the culture, was proposed. Online and off-line parameters measured during the culture brought a large number of data which were weighted by their respective variance associated to the measured value. The material balance resulted in an overdetermined linear system of equations made of weighted relationships including experimental data, elemental balances (C, H, O, N, S, Na), and an additional constraint. The mass balances involved in stoichiometric equations were solved using data reconciliation and linear algebra methods to take into account error measurements. This methodology allowed to establish the overall stoichiometric equation for each dilution rate studied.

  10. Physico-chemical aspects of the bovine growth hormone iodination by the electrolytic method

    International Nuclear Information System (INIS)

    Caro, R.A.; Ciscato, V.A.; Giacomini, S.M.V. de; Quiroga, S.; Kurcbart, H.; Radicella, R.

    1975-04-01

    With a view to studying the mechanism by which iodine is incorporated into the bovine somatotropin molecule, labelling was carried out by the electrolytic method (pH7.4, current 20 μA) as a function of time for various total iodine/protein ratios. In all cases the labelling yields were determined by paper electrophoresis. The corresponding degree of iodination was calculated on the basis of the values obtained and knowledge of the amount of reacting protein, values greater than 12 being obtained in many cases. Enzymatic hydrolysis was carried out on all the samples obtained and in the hydrolysates an increase in free iodide was observed which became more manifest as the iodide/protein molar ratio increased. The percentage of radioactivity from monoiodotyrosine and diiodotyrosine was determined for the various degrees of iodination from chromatograms of the hydrolysates. For an iodination value of 12, diiodotyrosine radioactivity of 70% was found. When the degree of relative iodination for each iodide/protein molar ratio is calculated from the hydrolysis data, it can be seen that only 75% of the total number of available places in the tyrosine residues accept the incorporation of iodine. This fact suggests that not all tyrosine residues are equally accessible. (author)

  11. Coarse-graining and hybrid methods for efficient simulation of stochastic multi-scale models of tumour growth

    Science.gov (United States)

    de la Cruz, Roberto; Guerrero, Pilar; Calvo, Juan; Alarcón, Tomás

    2017-12-01

    The development of hybrid methodologies is of current interest in both multi-scale modelling and stochastic reaction-diffusion systems regarding their applications to biology. We formulate a hybrid method for stochastic multi-scale models of cells populations that extends the remit of existing hybrid methods for reaction-diffusion systems. Such method is developed for a stochastic multi-scale model of tumour growth, i.e. population-dynamical models which account for the effects of intrinsic noise affecting both the number of cells and the intracellular dynamics. In order to formulate this method, we develop a coarse-grained approximation for both the full stochastic model and its mean-field limit. Such approximation involves averaging out the age-structure (which accounts for the multi-scale nature of the model) by assuming that the age distribution of the population settles onto equilibrium very fast. We then couple the coarse-grained mean-field model to the full stochastic multi-scale model. By doing so, within the mean-field region, we are neglecting noise in both cell numbers (population) and their birth rates (structure). This implies that, in addition to the issues that arise in stochastic-reaction diffusion systems, we need to account for the age-structure of the population when attempting to couple both descriptions. We exploit our coarse-graining model so that, within the mean-field region, the age-distribution is in equilibrium and we know its explicit form. This allows us to couple both domains consistently, as upon transference of cells from the mean-field to the stochastic region, we sample the equilibrium age distribution. Furthermore, our method allows us to investigate the effects of intracellular noise, i.e. fluctuations of the birth rate, on collective properties such as travelling wave velocity. We show that the combination of population and birth-rate noise gives rise to large fluctuations of the birth rate in the region at the leading edge of

  12. A mixed-methods study of mid-career science teachers: The growth of professional empowerment

    Science.gov (United States)

    Moreland, Amy Laphelia

    The purpose of this concurrent, mixed-methods study was to examine the professional empowerment qualities of mid-career (years 4-8), science teachers. I used the construct of professional empowerment as the theoretical frame to explore K-12 mid-career science teachers' career trajectories and consider how they can be supported professionally and ideally retained over time. In investigating the qualities of these teachers, I also constructed a new teaching trajectory model and tested the differences between mid-career and veteran science teachers. I analyzed seventy-eight surveys of mid-career science teachers across Texas, including six in-depth, interview-based case studies. The qualitative piece used behavior-over-time graphing combined with the interviews and the quantitative component used survey data from the Teacher Empowerment Survey (TES). Results indicated that science content knowledge gain through professional development opportunities was an especially important factor in supporting mid-career teachers' sense of empowerment. This increased content knowledge connected positively with the dimensions of decision-making, status, and impact. In a between-group analysis using a larger subset of TES data, I analyzed 254 surveys by conducting a nonparametric statistical test. A statistically significant difference was found between the two groups, in that mid-career science teachers had a lower sense of "status" than their more experienced counterparts (p empowerment. The study was situated within a broader scope of exploring how educational leaders and professional development providers can understand and support science teachers of varying experience levels. A well-designed and possibly differentiated professional development program could successfully connect with these kind of empowered and receptive mid-career science teachers, and thus increase the probability of implementing quality science education programs, content, and pedagogy into schools. The

  13. Time of Growth Dependent of ZnO-Nanorods by Self-Assembly Methods and its Structural Properties

    Science.gov (United States)

    Aprilia, A.; Bahtiar, A.; Safriani, L.; Ayunita, C. C.; Afifah, N.; Syakir, N.; Risdiana; Saragi, T.; Hidayat, S.; Fitrilawati; Siregar, R. E.

    2017-05-01

    ZnO-nanorods (ZnO-Nrs) have been successfully prepared on glass substrate using self-assembly method by varying deposition time. Zn acetate dehydrate and 2-methoxyethanol was used as raw material and solvent respectively (for ZnO seed layer preparation), meanwhile Zn nitrate hexahydrate and hexametylenetetramine (HMTA) dissolved in deionized water used as solution growth of ZnO-Nanorods (ZnO-Nrs). In this work, deposition times of ZnO-Nrs were varied by 120 min, 150 min, 180 min and 210 minutes at 100°C of annealing temperature. In order to investigate the physical properties of resulting ZnO, several measurements such as x-ray diffraction (XRD), ultra-violet visible spectroscopy and scanning electron microscopy (SEM) were carried out. Based on ZnO nanorods SEM image with varying time depositions, seems that increasing deposition time the nanorod size decrease but when the time reach 210 min, the average size of nanorods turned back increase. From XRD measurement, the average grain size and lattice constant (c) which is assemble the nanorod structure and lattice constant (c) was determined by Debye-Scherrer formula and Bragg law’s respectively. The growth process of ZnO nanorod by 180 min time deposition was known as an appropriate time to produce ZnO nanorods with high crystal quality due to sharp peak intensity of XRD spectrum.

  14. Inhibition of calcium carbonate crystal growth by organic additives using the constant composition method in conditions of recirculating cooling circuits

    Science.gov (United States)

    Chhim, Norinda; Kharbachi, Chams; Neveux, Thibaut; Bouteleux, Céline; Teychené, Sébastien; Biscans, Béatrice

    2017-08-01

    The cooling circuits used in power plants are subject to mineral crystallization which can cause scaling on the surfaces of equipment and construction materials reducing their heat exchange efficiency. Precipitated calcium carbonate is the predominant mineral scale commonly observed in cooling systems. Supersaturation is the key parameter controlling the nucleation and growth of calcite in these systems. The present work focuses on the precipitation of calcite using the constant composition method at constant supersaturation, through controlled addition of reactants to a semi-batch crystallizer, in order to maintain constant solution pH. The determination of the thermodynamic driving force (supersaturation) was based on the relevant chemical equilibria, total alkalinity and calculation of the activity coefficients. Calcite crystallization rates were derived from the experiments performed at supersaturation levels similar to those found in industrial station cooling circuits. Several types of seeds particles were added into the aqueous solution to mimic natural river water conditions in terms of suspended particulate matters content, typically: calcite, silica or illite particles. The effect of citric and copolycarboxylic additive inhibitors added to the aqueous solution was studied. The calcium carbonate growth rate was reduced by 38.6% in the presence of the citric additive and a reduction of 92.7% was observed when the copolycarboxylic additive was used under identical experimental conditions. These results are explained by the location of the adsorbed inhibitor at the crystal surface and by the degree of chemical bonding to the surface.

  15. Acute and Impaired Wound Healing: Pathophysiology and Current Methods for Drug Delivery, Part 2: Role of Growth Factors in Normal and Pathological Wound Healing: Therapeutic Potential and Methods of Delivery

    Science.gov (United States)

    Demidova-Rice, Tatiana N.; Hamblin, Michael R.; Herman, Ira M.

    2012-01-01

    This is the second of 2 articles that discuss the biology and pathophysiology of wound healing, reviewing the role that growth factors play in this process and describing the current methods for growth factor delivery into the wound bed. PMID:22820962

  16. Modeling the growth and interaction of stylolite networks, using the discrete element method for pressure solution

    Science.gov (United States)

    Makedonska, N.; Sparks, D. W.; Aharonov, E.

    2012-12-01

    Pressure solution (also termed chemical compaction) is considered the most important ductile deformation mechanism operating in the Earth's upper crust. This mechanism is a major player in a variety of geological processes, including evolution of sedimentary basins, hydrocarbon reservoirs, aquifers, earthquake recurrence cycles, and fault healing. Pressure solution in massive rocks often localizes into solution seams or stylolites. Field observations of stylolites often show elastic/brittle interactions in regions between pressure solution features, including and shear fractures, veins and pull-apart features. To understand these interactions, we use a grain-scale model based on the Discrete Element Method that allows granular dissolution at stressed contacts between grains. The new model captures both the slow chemical compaction process and the more abrupt brittle fracturing and sliding between grains. We simulate a sample of rock as a collection of particles, each representing either a grain or a unit of rock, bonded to each other with breakable cement. We apply external stresses to this sample, and calculate elastic and frictional interactions between the grains. Dissolution is modeled by an irreversible penetration of contacting grains into each other at a rate that depends on the contact stress and an adjustable rate constant. Experiments have shown that dissolution rates at grain contacts are greatly enhanced when there is a mineralogical contrast. Therefore, we dissolution rate constant can be increased to account for an amount of impurities (e.g. clay in a quartz or calcite sandstone) that can accumulate on dissolving contacts. This approach allows large compaction and shear strains within the rock, while allowing examination of local grain-scale heterogeneity. For example, we will describe the effect of pressure solution on the distribution of contact forces magnitudes and orientations. Contact forces in elastic granular packings are inherently

  17. A rapid, reliable method of evaluating growth and viability of intraerythrocytic protozoan hemoparasites using fluorescence flow cytometry.

    Science.gov (United States)

    Davis, W C; Wyatt, C R; Hamilton, M J; Goff, W L

    1992-01-01

    Fluorescence flow cytometry was employed to assess the potential of a vital dye, hydroethidine, for use in the detection and monitoring of the viability of hemoparasites in infected erythrocytes, using Babesia bovis as a model parasite. The studies demonstrated that hydroethidine is taken up by B. bovis and metabolically converted to the DNA binding fluorochrome, ethidium. Following uptake of the dye, erythrocytes containing viable parasites were readily distinguished and quantitated. Timed studies with the parasiticidal drug, Ganaseg, showed that it is possible to use the fluorochrome assay to monitor the effects of the drug on the rate of replication and viability of B. bovis in culture. The assay provides a rapid method for evaluation of the in vitro effect of drugs on hemoparasites and for analysis of the effect of various components of the immune response, such as lymphokines, monocyte products, antibodies, and effector cells (T, NK, LAK, ADCC) on the growth and viability of intraerythrocytic parasites.

  18. A rapid, reliable method of evaluating growth and viability of intraerythrocytic protozoan hemoparasites using fluorescence flow cytometry

    Directory of Open Access Journals (Sweden)

    W. C. Davis

    1992-01-01

    Full Text Available Fluorescence flow cytometry was employed to assess the potential of a vital dye, hydroethiedine, for use in the detection and monitoring of the viability of hemoparasites in infected erythrocytes, using Babesia bovis as a model parasite. The studies demonstrated that hydroethidine is taken up by B. bovis and metabolically converted to the DNA binding fluorochrone, ethidium. Following uptake of the dye, erythrocytes contamine viable parasites were readily distinguished and quantitated. Timed studies with the parasiticidal drug, Ganaseg, showed that it is possible to use the fluorochrome assay to monitor the effects of the drug on the rate of replication and viability of B. bovis in culture. The assay provides a rapid method for evaluation of the in vitro effect of drugs on hemoparasites and for analysis of the effect of various components of the immune response, such as lymphokines, monocyte products, antibodies, and effector cells (T, NK, LAK, ADCC on the growth and viability of intraerythrocytic parasites.

  19. Melt growth of zinc aluminate spinel single crystal by the micro-pulling down method under atmospheric pressure

    Science.gov (United States)

    Kamada, K.; Shoji, Y.; Yamaji, A.; Kurosawa, S.; Yokota, Yuui; Ohashi, Y.; Kim, Kyoung Jin; Ivanov, M.; Kochurikhin, V. V.; Yoshikawa, A.

    2018-06-01

    ZnAl2O4 crystals were grown using few starting compositions with various ZnO:AlO3/2 ratio using an Ir wire seed and Ir + Re crucible under ordinary pressure with Ar + 2%O2 atmosphere by the radiofrequency heating μ-PD furnace. The ZnAl2O4 spinel single crystal with 4 mm diameter could be successfully grown by the μ-PD method by optimization of starting melt composition considering with Zinc oxide evaporation. During 10 min of growth under normal pressure the formation of ZnAl2O4 single phase observed even at high vapor pressure of ZnO. The transmittance spectra and X-ray locking curve were measured for evaluating of grown ZnAl2O4 crystals quality.

  20. Numerical analysis of interfacial growth and deformation in horizontal stratified two-phase flow by lattice Boltzmann method

    International Nuclear Information System (INIS)

    Ebihara, Ken-ichi

    2005-03-01

    paper, first, the validity and the usefulness of the lattice-gas model and the lattice Boltzmann method for the numerical analysis of two-phase flow are examined by applying the two-phase fluid model of these methods to the phenomena of the falling droplet and the rising bubble. Next, on the basis of the examination of its numerical results, the horizontal stratified two-phase flow, which is the fundamental and important flow and often observed in a practical situation, is simulated by use of the HCZ model that is the two-phase fluid model of the lattice Boltzmann method proposed by He, Chen, and Zhang. The HCZ model can simulate Rayleigh-Taylor instability which shows complex interfacial phenomena. It is verified that the simulated interfacial growth is subject to the Kelvin-Helmholtz instability theory and can reproduce the curve concerning the interfacial growth of the theoretical flow regime map proposed by Taitel and Dukler (T-D map). Furthermore, it is found that the interfacial growth in the channel with the narrow width needs more superficial flow velocity than that given by the T-D map. In the simulation of the droplet generation in the horizontal stratified two-phase flow, it is verified that the HCZ model can also reproduce the experimental correlation proposed by Ishii and Grolmes within the range of the distribution of experimental data. According to the results of this report, it is found that the HCZ model of the lattice Boltzmann method can simulate complex interfacial phenomena in the horizontal stratified two-phase flow and reproduce the theoretical flow regime map and the experimental correlation. Considering the application of this model to more practical two-phase flow, it is also seen that this model has some problems which have to be solved, such as practical density difference, thermal influence and so on. (author)

  1. Real-time growth study of plasma assisted atomic layer epitaxy of InN films by synchrotron x-ray methods

    Energy Technology Data Exchange (ETDEWEB)

    Nepal, Neeraj [U.S. Naval Research Laboratory, 4555 Overlook Avenue SW, Washington, DC 20375; Anderson, Virginia R. [American Society for Engineering Education, 1818 N Street NW, Washington, DC 20036; Johnson, Scooter D. [U.S. Naval Research Laboratory, 4555 Overlook Avenue SW, Washington, DC 20375; Downey, Brian P. [U.S. Naval Research Laboratory, 4555 Overlook Avenue SW, Washington, DC 20375; Meyer, David J. [U.S. Naval Research Laboratory, 4555 Overlook Avenue SW, Washington, DC 20375; DeMasi, Alexander [Physics Department, Boston University, 590 Commonwealth Avenue, Boston, Massachusetts 02215; Robinson, Zachary R. [Department of Physics, SUNY College at Brockport, 350 New Campus Dr, Brockport, New York 14420; Ludwig, Karl F. [Physics Department, Boston University, 590 Commonwealth Avenue, Boston, Massachusetts 02215; Eddy, Charles R. [U.S. Naval Research Laboratory, 4555 Overlook Avenue SW, Washington, DC 20375

    2017-03-13

    The temporal evolution of high quality indium nitride (InN) growth by plasma-assisted atomic layer epitaxy (ALEp) on a-plane sapphire at 200 and 248 °C was probed by synchrotron x-ray methods. The growth was carried out in a thin film growth facility installed at beamline X21 of the National Synchrotron Light Source at Brookhaven National Laboratory and at beamline G3 of the Cornell High Energy Synchrotron Source, Cornell University. Measurements of grazing incidence small angle x-ray scattering (GISAXS) during the initial cycles of growth revealed a broadening and scattering near the diffuse specular rod and the development of scattering intensities due to half unit cell thick nucleation islands in the Yoneda wing with correlation length scale of 7.1 and 8.2 nm, at growth temperatures (Tg) of 200 and 248 °C, respectively. At about 1.1 nm (two unit cells) of growth thickness nucleation islands coarsen, grow, and the intensity of correlated scattering peak increased at the correlation length scale of 8.0 and 8.7 nm for Tg = 200 and 248 °C, respectively. The correlated peaks at both growth temperatures can be fitted with a single peak Lorentzian function, which support single mode growth. Post-growth in situ x-ray reflectivity measurements indicate a growth rate of ~0.36 Å/cycle consistent with the growth rate previously reported for self-limited InN growth in a commercial ALEp reactor. Consistent with the in situ GISAXS study, ex situ atomic force microscopy power spectral density measurements also indicate single mode growth. Electrical characterization of the resulting film revealed an electron mobility of 50 cm2/V s for a 5.6 nm thick InN film on a-plane sapphire, which is higher than the previously reported mobility of much thicker InN films grown at higher temperature by molecular beam epitaxy directly on sapphire. These early results indicated that in situ synchrotron x-ray study of the epitaxial growth kinetics of InN films is a very powerful method to

  2. Growth of Bi doped cadmium zinc telluride single crystals by Bridgman oscillation method and its structural, optical, and electrical analyses

    International Nuclear Information System (INIS)

    Carcelen, V.; Rodriguez-Fernandez, J.; Dieguez, E.; Hidalgo, P.

    2010-01-01

    The II-VI compound semiconductor cadmium zinc telluride (CZT) is very useful for room temperature radiation detection applications. In the present research, we have successfully grown Bi doped CZT single crystals with two different zinc concentrations (8 and 14 at. %) by the Bridgman oscillation method, in which one experiment has been carried out with a platinum (Pt) tube as the ampoule support. Pt also acts as a cold finger and reduces the growth velocity and enhances crystalline perfection. The grown single crystals have been studied with different analysis methods. The stoichiometry was confirmed by energy dispersive by x-ray and inductively coupled plasma mass spectroscopy analyses and it was found there is no incorporation of impurities in the grown crystal. The presence of Cd and Te vacancies was determined by cathodoluminescence studies. Electrical properties were assessed by I-V analysis and indicated higher resistive value (8.53x10 8 Ω cm) for the crystal grown with higher zinc concentration (with Cd excess) compare to the other (3.71x10 5 Ω cm).

  3. An Improved Method of Mitigating Laser Induced Surface Damage Growth in Fused Silica Using a Rastered, Pulsed CO2 Laser

    Energy Technology Data Exchange (ETDEWEB)

    Bass, I L; Guss, G M; Nostrand, M J; Wegner, P L

    2010-10-21

    A new method of mitigating (arresting) the growth of large (>200 m diameter and depth) laser induced surface damage on fused silica has been developed that successfully addresses several issues encountered with our previously-reported large site mitigation technique. As in the previous work, a tightly-focused 10.6 {micro}m CO{sub 2} laser spot is scanned over the damage site by galvanometer steering mirrors. In contrast to the previous work, the laser is pulsed instead of CW, with the pulse length and repetition frequency chosen to allow substantial cooling between pulses. This cooling has the important effect of reducing the heat-affected zone capable of supporting thermo-capillary flow from scale lengths on the order of the overall scan pattern to scale lengths on the order of the focused laser spot, thus preventing the formation of a raised rim around the final mitigation site and its consequent down-stream intensification. Other advantages of the new method include lower residual stresses, and improved damage threshold associated with reduced amounts of redeposited material. The raster patterns can be designed to produce specific shapes of the mitigation pit including cones and pyramids. Details of the new technique and its comparison with the previous technique will be presented.

  4. Effects of the pH/pCO2 control method in the growth medium of phytoplankton

    Science.gov (United States)

    Shi, D.; Xu, Y.; Morel, F. M. M.

    2009-02-01

    To study the effects of ocean acidification on the physiology of phytoplankton requires that the key chemical parameters of the growth medium, pCO2, pH and Ω (the saturation state of calcium carbonate) be carefully controlled. This is made difficult by the interdependence of these parameters. Moreover, in growing batch cultures of phytoplankton, the fixation of CO2, the uptake of nutrients and, for coccolithophores, the precipitation of calcite all change the inorganic carbon and acid-base chemistry of the medium. For example, absent pH-buffering or CO2 bubbling, a sizeable decrease in pCO2 occurs at a biomass concentration as low as 50 μM C in non-calcifying cultures. Even in cultures where pCO2 or pH is maintained constant, other chemical parameters change substantially at high cell densities. The quantification of these changes is facilitated by the use of buffer capacities. Experimentally we observe that all methods of adjustment of pCO2/pH can be used, the choice of one or the other depending on the specifics of the experiments. The mechanical effect of bubbling of cultures seems to induce more variable results than other methods of pCO2/pH control. While highly convenient, the addition of pH buffers to the medium induces changes in trace metal availability and cannot be used under trace metal-limiting conditions.

  5. Growth Mechanism of γ-MnS Nanorod-Arrays by Hydrothermal Method on Anodic Aluminum Oxide Template

    International Nuclear Information System (INIS)

    Huang, Jianming; Liu, Weifeng; Lv, Yong; Yao, Lianzeng

    2010-01-01

    Hydrothermal method is a general, low-cost and convenience method which was utilized for synthesis of nanomaterials. Our research group has reported that oriented MnS nanorods on anodic aluminum oxide template were synthesized under a hydrothermal condition and demonstrated the effect of precursor content on the morphology evolution of as-samples. In order to research the growth mechanism of the arrays, herein we synthesized MnS nanorod arrays by combination of anodic aluminum oxide template and hydrothermal method on different substrates. Through-hole anodic aluminum oxide templates were prepared using Al foil (99.999%) via a two-step anodization process as described in literature. To investigate the effect of different substrates on the morphology of the-products, different substrates including anodic aluminum oxide template (sample A), one-step anodization Al foil (sample B, which was prepared by first anodizing Al foil for 10h and then removing the alumina layer with the mixed acid (0.6 M H 3 PO 4 and 0.15 M H 2 CrO 4 ), where the foil still kept the close-packed concave nano-pits consistently with the nanopole of anodic aluminum oxide template), Al foil (sample C, dipped in HNO 3 solution and covered by a compact alumina layer), Si wafer (sample D) respectively were put into Teflon-lined stainless steel autoclaves of 20 mL capacity filled with 16 mL mixed solution consisting of 2 mol/L MnCl 4 and 2 mol/L thiourea. We kept the reaction at 150 .deg. C for 20 h. When reactions completed the products were washed three times with distilled water and absolute ethanol, respectively. Then the products were dried in an oven at 60 .deg. C

  6. Growth Mechanism of γ-MnS Nanorod-Arrays by Hydrothermal Method on Anodic Aluminum Oxide Template

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Jianming; Liu, Weifeng; Lv, Yong; Yao, Lianzeng [Chinese Academy of Science, Hefei, Anhui (China)

    2010-09-15

    Hydrothermal method is a general, low-cost and convenience method which was utilized for synthesis of nanomaterials. Our research group has reported that oriented MnS nanorods on anodic aluminum oxide template were synthesized under a hydrothermal condition and demonstrated the effect of precursor content on the morphology evolution of as-samples. In order to research the growth mechanism of the arrays, herein we synthesized MnS nanorod arrays by combination of anodic aluminum oxide template and hydrothermal method on different substrates. Through-hole anodic aluminum oxide templates were prepared using Al foil (99.999%) via a two-step anodization process as described in literature. To investigate the effect of different substrates on the morphology of the-products, different substrates including anodic aluminum oxide template (sample A), one-step anodization Al foil (sample B, which was prepared by first anodizing Al foil for 10h and then removing the alumina layer with the mixed acid (0.6 M H{sub 3}PO{sub 4} and 0.15 M H{sub 2}CrO{sub 4}), where the foil still kept the close-packed concave nano-pits consistently with the nanopole of anodic aluminum oxide template), Al foil (sample C, dipped in HNO{sub 3} solution and covered by a compact alumina layer), Si wafer (sample D) respectively were put into Teflon-lined stainless steel autoclaves of 20 mL capacity filled with 16 mL mixed solution consisting of 2 mol/L MnCl{sub 4} and 2 mol/L thiourea. We kept the reaction at 150 .deg. C for 20 h. When reactions completed the products were washed three times with distilled water and absolute ethanol, respectively. Then the products were dried in an oven at 60 .deg. C.

  7. InGaN nanocolumn growth self-induced by in-situ annealing and ion irradiation during growth process with molecular beam epitaxy method

    Science.gov (United States)

    Xue, Junjun; Cai, Qing; Zhang, Baohua; Ge, Mei; Chen, Dunjun; Zheng, Jianguo; Zhi, Ting; Tao, Zhikuo; Chen, Jiangwei; Wang, Lianhui; Zhang, Rong; Zheng, Youdou

    2017-11-01

    Incubation and shape transition are considered as two essential processes for nucleating of self-assembly InGaN nanocolumns (NCs) in traditional way. We propose a new approach for nuclei forming directly by in-situ annealing and ion irradiating the InGaN template during growing process. The nanoislands, considered as the nuclei of NCs, were formed by a combinational effect of thermal and ion etching (TIE), which made the gaps of the V-pits deeper and wider. On account of the decomposition of InGaN during TIE process, more nitride-rich amorphous alloys would intent to accumulate in the corroded V-pits. The amorphous alloys played a key role to promote the following growth from 2D regime into Volmer-Weber growth regime so that the NC morphology took place, rather than a compact film. As growth continued, the subsequently epitaxial InGaN alloys on the annealed NC nuclei were suffered in biaxial compressive stress for losing part of indium content from the NC nuclei during the TIE process. Strain relaxation, accompanied by thread dislocations, came up and made the lattice planes misoriented, which prevented the NCs from coalescence into a compact film at later period of growing.

  8. An Improved Version of the Cervical Vertebral Maturation (CVM) Method for the Assessment of Mandibular Growth in Deutero-Malay Sub Race

    Science.gov (United States)

    Oscandar, Fahmi; Malinda, Yuti; Azhari, H.; Murniati, Nani; Yeh Ong, Sing; Subiyanto; Supian, Sudradjat

    2018-01-01

    In this paper, Cervical Vertebral Maturation method was used to assess the mandibular growth in Deutero-Malay sub race. Twenty eight laterals Cephalometric radiographs of Deutero-Malay sub race aged 9-15 were observed. The observation used stratified random sampling by measuring the quantitative and qualitative assessment of the 2nd through 4th cervical vertebra of the subjects. It produced the diagram of developmental stages of cervical vertebrae for Deutero-Malay sub race. The diagram can be used to determine mandibular growth in term of qualitative by matching the shape of cervical vertebrae. It was obtained that the Cervical Vertebral Maturation method can be used to assess mandibular growth in Deutero-Malay sub race by matching the shape of cervical vertebrae to the diagram of developmental stages of cervical vertebrae. In addition, Cervical Vertebral Maturation method can be used to identification person’s age.

  9. Experimental and theoretical analysis of the rate of solvent equilibration in the hanging drop method of protein crystal growth

    Science.gov (United States)

    Fowlis, William W.; Delucas, Lawrence J.; Twigg, Pamela J.; Howard, Sandra B.; Meehan, Edward J.

    1988-01-01

    The principles of the hanging-drop method of crystal growth are discussed, and the rate of water evaporation in a water droplet (containing protein, buffer, and a precipitating agent) suspended above a well containing a double concentration of precipitating agent is investigated theoretically. It is shown that, on earth, the rate of evaporation may be determined from diffusion theory and the colligative properties of solutions. The parameters affecting the rate of evaporation include the temperature, the vapor pressure of water, the ionization constant of the salt, the volume of the drop, the contact angle between the droplet and the coverslip, the number of moles of salt in the droplet, the number of moles of water and salt in the well, the molar volumes of water and salt, the distance from the droplet to the well, and the coefficient of diffusion of water vapor through air. To test the theoretical equations, hanging-drop experiments were conducted using various reagent concentrations in 25-microliter droplets and measuring the evaporation times at 4 C and 25 C. The results showed good agreement with the theory.

  10. Growth of Yb3+-doped Y2O3 single crystal rods by the micro-pulling-down method

    International Nuclear Information System (INIS)

    Mun, J.H.; Novoselov, A.; Yoshikawa, A.; Boulon, G.; Fukuda, T.

    2005-01-01

    The rare-earth sesquioxides (RE 2 O 3 , RE = Lu, Y and Sc) are very promising host crystals for advanced laser diode (LD)-pumped Yb 3+ -doped solid-state lasers due to unusual combination, almost unique of favourable structural, thermal and spectroscopic properties which are described. In spite of these favourable properties, the bulk single crystal growth technology for the rare-earth sesquioxides has not been established yet. The extremely high melting temperature at around 2400 deg. C has prevented it. However, we shall show that yttrium oxide crystals (Yb x Y 1-x ) 2 O 3 , x = 0.0, 0.005, 0.05, 0.08 and 0.15 of cylindrical shape as laser rods with 4.2 mm in diameter and 15-20 mm in length have been grown from rhenium crucibles by the micro-pulling-down method. The crystal quality characterisation of undoped Y 2 O 3 crystal was determined using X-ray rocking curve (XRC) analysis. Yb were homogeneously distributed in Y 2 O 3 host crystal

  11. Water Assisted Growth of C60 Rods and Tubes by Liquid–Liquid Interfacial Precipitation Method

    Directory of Open Access Journals (Sweden)

    Cheuk-Wai Tai

    2012-06-01

    Full Text Available C60 nanorods with hexagonal cross sections are grown using a static liquid–liquid interfacial precipitation method in a system of C60/m-dichlorobenzene solution and ethanol. Adding water to the ethanol phase leads instead to C60 tubes where both length and diameter of the C60 tubes can be controlled by the water content in the ethanol. Based on our observations we find that the diameter of the rods/tubes strongly depends on the nucleation step. We propose a liquid-liquid interface growth model of C60 rods and tubes based on the diffusion rate of the good C60 containing solvent into the poor solvent as well as on the size of the crystal seeds formed at the interface between the two solvents. The grown rods and tubes exhibit a hexagonal solvate crystal structure with m-dichlorobenzene solvent molecules incorporated into the crystal structure, independent of the water content. An annealing step at 200 °C at a pressure < 1 kPa transforms the grown structures into a solvent-free face centered cubic structure. Both the hexagonal and the face centered cubic structures are very stable and neither morphology nor structure shows any signs of degradation after three months of storage.

  12. Release potential of single-wall carbon nanotubes produced by super-growth method during manufacturing and handling

    International Nuclear Information System (INIS)

    Ogura, Isamu; Sakurai, Hiromu; Mizuno, Kohei; Gamo, Masashi

    2011-01-01

    We investigated the release potential of single-wall carbon nanotubes (CNTs) produced by the super-growth method during their manufacturing and handling processes at a research facility. We generally sampled air at points both outside and inside of protective enclosures such as a glove box and fume hood. Sampling the air outside of the enclosures was intended to evaluate the actual exposure of workers to CNTs, while sampling the air inside the enclosures was performed to quantify the release of CNTs to the air in order to estimate the potential exposure of workers without protection. The results revealed that airborne CNTs were generated when (1) CNTs were separated from the substrates using a spatula and placed in a container in a glove box; (2) an air gun was used to clean the air filters (containing dust that included CNTs) of a vacuum cleaner; (3) a vacuum cleaner was used to collect CNTs (emission with exhaust air from the cleaner); (4) the container of CNTs was opened; and (5) CNTs in the bin of the cleaner were transferred to a container. In these processes, airborne CNTs were only found inside the enclosures, except for a small amount of CNTs released from the glove box when it was opened. Electron microscopic observations of aerosol particles found CNT clusters, which were fragments of CNT forests, with sizes ranging from submicrometers to tens of micrometers.

  13. A proposal for evaluation method of crack growth due to cyclic overload for piping materials based on an elastic-plastic fracture mechanics parameter

    International Nuclear Information System (INIS)

    Yamaguchi, Yoshihito; Katsuyama, Jinya; Onizawa, Kunio; Li, Yinsheng; Sugino, Hideharu

    2011-01-01

    The magnitude of Niigata-ken Chuetsu-Oki earthquake in 2007 was beyond the assumed one provided in seismic design. Therefore it becomes an important issue to evaluate the crack growth behaviors due to the cyclic overload like large earthquake. Fatigue crack growth is usually evaluated by Paris's law using the range of stress intensity factor (ΔK). However, ΔK is inappropriate in a loading condition beyond small scale yielding. In this study, the crack growth behaviors for piping materials were investigated based on an elastic-plastic fracture mechanics parameter, J-integral. It was indicated that the crack growth due to the cyclic overload beyond small scale yielding could be the sum of fatigue and ductile crack growth. The retardation effect of excessive loading on the crack growth was observed after the loading. The modified Wheeler model using J-integral has been proposed for the prediction of retardation effect. Finally, an evaluation method for crack growth behaviors due to the cyclic overload is suggested. (author)

  14. Effect of Strain Restored Energy on Abnormal Grain Growth in Mg Alloy Simulated by Phase Field Methods

    Science.gov (United States)

    Wu, Yan; Huang, Yuan-yuan

    2018-03-01

    Abnormal grain growth of single phase AZ31 Mg alloy in the spatio-temporal process has been simulated by phase field models, and the influencing factors of abnormal grain growth are studied in order to find the ways to control secondary recrystallization in the microstructure. The study aims to find out the mechanisms for abnormal grain growth in real alloys. It is shown from the simulated results that the abnormal grain growth can be controlled by the strain restored energy. Secondary recrystallization after an annealing treatment can be induced if there are grains of a certain orientation in the microstructure with local high restored energy. However, if the value of the local restored energy at a certain grain orientation is not greater than 1.1E 0, there may be no abnormal grain growth in the microstructure.

  15. 14C/C measurements support Andreev's internode method to determine lichen growth rates in Cladina stygia (Fr.) Ahti

    Energy Technology Data Exchange (ETDEWEB)

    Holt, E; Bench, G

    2007-12-05

    Growth rates and the ability to date an organism can greatly contribute to understanding its population biology and community dynamics. 1n 1954, Andreev proposed a method to date Cladina, a fruticose lichen, using total thallus length and number of internodes. No research, however, has demonstrated the reliability of this technique or compared its estimates to those derived by other means. In this study, we demonstrate the utility of {sup 14}C/C ratios to determine lichen age and growth rate in Cladina stygia (Fr.) Ahti collected from northwestern Alaska, USA. The average growth rate using {sup 14}C/C ratios was 6.5 mm {center_dot} yr{sup -1}, which was not significantly different from growth rates derived by Andreev's internode method (average = 6.2 mm {center_dot} yr{sup -1}); thus, suggesting the reliability of Andreev's simple field method for dating lichens. In addition, we found lichen growth rates appeared to differ with geographic location, yet did not seem related to ambient temperature and total precipitation.

  16. A simple method to evaluate the fission gas release at fuel grain boundary including the grain growth both at constant and at transient power histories

    International Nuclear Information System (INIS)

    Paraschiv, M.; Paraschiv, A.

    1991-01-01

    A method to rewrite Fick's second law for a region with a moving boundary when the moving law in time of this boundary is known, has been proposed. This method was applied to Booth's sphere model for radioactive and stable fission product diffusion from the oxide fuel grain in order to take into account the grain growth. The solution of this new equation was presented in the mathematical formulation for power histories from ANS 5.4 model for the stable species. It is very simple to apply and very accurate. The results obtained with this solution for constant and transient temperatures show that the fission gas release (FGR) at grain boundary is strongly dependent on kinetics of grain growth. The utilization of two semiempirical grain growth laws, from published information, shows that the fuel microstructural properties need to be multicitly considered in the fission gas release for every manufacturer of fuel. (orig.)

  17. Banned antibacterial growth promoters in animal feed: Collaborative trial on the liquid chromatography-tandem mass spectrometry method developed in the feedstuffs-radius project

    NARCIS (Netherlands)

    Poucke, C.V.; Dumoulin, F.; Yakkundi, S.; Situ, C.; Elliott, C.T.; Grutters, E.M.; Verheijen, R.; Schilt, R.; Eriksson, S.; Peteghem, C.V.

    2006-01-01

    A chemical confirmation method for the identification and quantification of five banned antibacterial growth promoters (AGPs) in animal feed was developed and in-house validated as part of the European Feedstuffs-RADIUS project [1]. To complete the validation process a collaborative trial was

  18. The Impact of Student Teaching Experience on Pre-Service Teachers' Readiness for Technology Integration: A Mixed Methods Study with Growth Curve Modeling

    Science.gov (United States)

    Sun, Yan; Strobel, Johannes; Newby, Timothy J.

    2017-01-01

    Adopting a two-phase explanatory sequential mixed methods research design, the current study examined the impact of student teaching experiences on pre-service teachers' readiness for technology integration. In phase-1 of quantitative investigation, 2-level growth curve models were fitted using online repeated measures survey data collected from…

  19. Growth and luminescence properties of Eu:SrI.sub.2./sub. single crystals prepared by modified micro-pulling-down method

    Czech Academy of Sciences Publication Activity Database

    Král, Robert; Jarý, Vítězslav; Pejchal, Jan; Kurosawa, S.; Nitsch, Karel; Yokota, Y.; Nikl, Martin; Yoshikawa, A.

    2016-01-01

    Roč. 63, č. 2 (2016), s. 453-458 ISSN 0018-9499 R&D Projects: GA MŠk(CZ) LH14266 Institutional support: RVO:68378271 Keywords : Eu 2+ and Eu 3+ doping * crystal growth * luminescence * micro-pulling-down method * strontium iodide Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.171, year: 2016

  20. Equiaxed and columnar dendrite growth simulation in Al-7Si- Mg ternary alloys using cellular automaton method

    International Nuclear Information System (INIS)

    Chen, Rui; Xu, Qingyan; Liu, Baicheng

    2015-01-01

    In this paper, a modified cellular automaton (MCA) model allowing for the prediction of dendrite growth of Al-Si-Mg ternary alloys in two and three dimensions is presented. The growth kinetic of S/L interface is calculated based on the solute equilibrium approach. In order to describe the dendrite growth with arbitrarily crystallographic orientations, this model introduces a modified decentered octahedron algorithm for neighborhood tracking to eliminate the effect of mesh dependency on dendrite growth. The thermody namic and kinetic data needed for dendrite growth is obtained through coupling with Pandat software package in combination with thermodynamic/kinetic/equilibrium phase diagram calculation databases. The effect of interactions between various alloying elements on solute diffusion coefficient is considered in the model. This model has first been used to simulate Al-7Si (weight percent) binary dendrite growth followed by a validation using theoretical predictions. For ternary alloy, Al-7Si-0.5Mg dendrite simulation has been carried out and the effects of solute interactions on diffusion matrix as well as the differences of Si and Mg in solute distribution have been analyzed. For actual application, this model has been applied to simulate the equiaxed dendrite growth with various crystallographic orientations of Al-7Si-0.36Mg ternary alloy, and the predicted secondary dendrite arm spacing (SDAS) shows a reasonable agreement with the experimental ones. Furthermore, the columnar dendrite growth in directional solidification has also been simulated and the predicted primary dendrite arm spacing (PDAS) is in good agreement with experiments. The simulated results effectively demonstrate the abilities of the model in prediction of dendritic microstructure of Al-Si-Mg ternary alloy. (paper)

  1. Equiaxed and columnar dendrite growth simulation in Al-7Si- Mg ternary alloys using cellular automaton method

    Science.gov (United States)

    Chen, Rui; Xu, Qingyan; Liu, Baicheng

    2015-06-01

    In this paper, a modified cellular automaton (MCA) model allowing for the prediction of dendrite growth of Al-Si-Mg ternary alloys in two and three dimensions is presented. The growth kinetic of S/L interface is calculated based on the solute equilibrium approach. In order to describe the dendrite growth with arbitrarily crystallographic orientations, this model introduces a modified decentered octahedron algorithm for neighborhood tracking to eliminate the effect of mesh dependency on dendrite growth. The thermody namic and kinetic data needed for dendrite growth is obtained through coupling with Pandat software package in combination with thermodynamic/kinetic/equilibrium phase diagram calculation databases. The effect of interactions between various alloying elements on solute diffusion coefficient is considered in the model. This model has first been used to simulate Al-7Si (weight percent) binary dendrite growth followed by a validation using theoretical predictions. For ternary alloy, Al-7Si-0.5Mg dendrite simulation has been carried out and the effects of solute interactions on diffusion matrix as well as the differences of Si and Mg in solute distribution have been analyzed. For actual application, this model has been applied to simulate the equiaxed dendrite growth with various crystallographic orientations of Al-7Si-0.36Mg ternary alloy, and the predicted secondary dendrite arm spacing (SDAS) shows a reasonable agreement with the experimental ones. Furthermore, the columnar dendrite growth in directional solidification has also been simulated and the predicted primary dendrite arm spacing (PDAS) is in good agreement with experiments. The simulated results effectively demonstrate the abilities of the model in prediction of dendritic microstructure of Al-Si-Mg ternary alloy.

  2. Growth dynamics of SiGe nanowires by the Vapour Liquid Solid method and its impact on SiGe/Si axial heterojunction abruptness.

    Science.gov (United States)

    Pura, Jose Luis; Periwal, Priyanka; Baron, Thierry; Jimenez, Juan

    2018-06-05

    The Vapour Liquid Solid (VLS) method is by far the most extended procedure for bottom-up nanowire growth. This method also allows for the manufacture of nanowire axial heterojunctions in a straightforward way. To do this, during the growth process the precursor gases are switched on/off to obtain the desired change in the nanowire composition. Using this technique axially heterostructured nanowires can be grown, which are crucial for the fabrication of electronic and optoelectronic devices. SiGe/Si nanowires are compatible with Complementary Metal Oxide Semiconductor (CMOS) technology, this improves their versatility and the possibility of integration with the current electronic technologies. Abrupt heterointerfaces are fundamental for the development and correct operation of electronic and optoelectronic devices. Unfortunately, VLS growth of SiGe/Si heterojunctions does not provide abrupt transitions because of the high solubility of group IV semiconductors in Au, with the corresponding reservoir effect that precludes the growth of sharp interfaces. In this work, we studied the growth dynamics of SiGe/Si heterojunctions based on already developed models for VLS growth. A composition map of the Si-Ge-Au liquid alloy is proposed to better understand the impact of the growing conditions on the nanowire growth process and the heterojunction formation. The solution of our model provides heterojunction profiles in good agreement with experimental measurements. Finally, the in-depth study of the composition map provides a practical approach to reduce drastically the heterojunction abruptness by reducing the Si and Ge concentrations in the catalyst droplet. This converges with previous approaches that use catalysts aiming to reduce the solubility of the atomic species. This analysis opens new paths to reduce the heterojunction abruptness using Au catalysts, but the model can be naturally extended to other catalysts and semiconductors. © 2018 IOP Publishing Ltd.

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

    Science.gov (United States)

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

    2018-02-01

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

  4. Numerical analysis of transport phenomena in Y-Ba-Cu-O melt during growth of superconducting crystal Y123 by Czochralski method

    Science.gov (United States)

    Szmyd, J. S.; Suzuki, K.

    2003-10-01

    In 1993, at the Superconductivity Research Laboratory (SRL), International Superconductivity Technology Centre (ISTEC), in Tokyo, continuous growth of large single crystals of YBa 2Cu 3O 7- x (Y123) was achieved by the application of a modified Czochralski method. This paper presents the numerical computations of the flow, thermal and Y concentration fields in the Ba-Cu-O melt for Y123 single crystal growth by this modified method. The finite volume method was used to calculate the fluid flow, heat transfer and yttrium distribution in the melt with staggered numerical grid. The flow in the melt was modelled as an incompressible Newtonian and Boussinesque fluid. Calculations are presented for a combined flow regime of buoyancy-driven natural convection and crystal-rotation-driven forced convection.

  5. A new direct growth method of graphene on Si-face of 6H-SiC by synergy of the inner and external carbon sources

    Science.gov (United States)

    Yang, Zhiyuan; Xu, Shicai; Zhao, Lili; Zhang, Jing; Wang, Zhengping; Chen, Xiufang; Cheng, Xiufeng; Yu, Fapeng; Zhao, Xian

    2018-04-01

    Graphene is a promising two-dimensional material that has possible application in various disciplines, due to its super properties, including high carrier mobility, chemical stability, and optical transparency etc. In this paper, we report an inner and external carbon synergy (IECS) method to grow graphene on Si-face of 6H-SiC. This method combined the advantages of chemical vapor deposition (CVD) and traditional epitaxial growth (EG) based on silicon carbide, which providing a feasible approach for growing graphene on the SiC substrates. The graphene was synthesized within just 3 min, which was more than one order of magnitude faster than the graphene grown on 6H-SiC substrates by the traditional EG method. The growth temperature was ∼200 °C lower than the EG process. The directly grown graphene maintained the compatibility with the semiconductor technique, which is benefit for use in graphene-based microelectronic devices.

  6. High-precision improved-analytic-exponentiation results for multiple-photon effects in low-angle Bhabha scattering at the SLAC Linear Collider and the CERN e+e- collider LEP

    International Nuclear Information System (INIS)

    Jadach, S.; Richter-Was, E.; Ward, B.F.L.; Was, Z.

    1991-01-01

    Starting from an earlier benchmark analytical calculation of the luminosity process e + e-→e + e-+(γ) at the SLAC Linear Collider (SLC) and the CERN e + e- collider LEP, we use the methods of Yennie, Frautschi, and Suura to develop an analytical improved naive exponentiated formula for this process. The formula is compared to our multiple-photon Monte Carlo event generator BHLUMI (1.13) for the same process. We find agreement on the overall cross-section normalization between the exponentiated formula and BHLUMI below the 0.2% level. In this way, we obtain an important cross-check on the normalization of our higher-order results in BHLUMI and we arrive at formulas which represent the LEP/SLC luminosity process in the below 1% Z 0 physics tests of the SU(2) L xU(1) theory in complete analogy with the famous high-precision Z 0 line-shape formulas for the e + e-→μ + μ - process discussed by Berends et al., for example

  7. Preincubation of Penicillium commune conidia under modified atmosphere conditions: Influence on growth potential as determined by an impedimetric method

    DEFF Research Database (Denmark)

    Haasum, Iben; Nielsen, Per Væggemose

    1996-01-01

    The combined effect of preincubation time, relative humidity (r.h.), headspace carbon dioxide (CO2) and oxygen (O2) on subsequent growth potential of conidia from Penicillium commune was studied using Response Surface Modelling (RSM). Native conidia were preincubated under modified atmosphere...... conditions in sealed vials for 14, 35 and 56 d. Lag time and growth rates were determined using impedance microbiology on a Bactometer. Conidia survived and some swelling was observed during all experimental preincubation conditions. Regression analysis of the subsequent growth responses showed that relative...... humidity in the vials was the most significant factor affecting lag time of the conidia after preincubation for 14 and 35 d. Storage for 35 d extended lag times by 15 h when the level of r.h. was increased from 41% to 80%. After prolonged storage (56 d) r.h and CO2 levels elicited a significant effect...

  8. Ge-Si single crystal growth when the begining of an ingot prepared by a new method is used as the begining of the feeding alloy

    International Nuclear Information System (INIS)

    Tahirov, V.I.; Quliyev, A.F.; Hasanov, Z.Y.; Qahramanov, N.F.

    2008-01-01

    Ge-Si system is used to describe binary solid solution single crystal growth when the beginning of the ingot prepared by a new method is used as the beginning of the feeding alloy. At first the feeding ingot is prepared by Bridgman method, then it is exposed to the zone melting. Content distribution of the feeding alloy and the grown crystal is determined by solving the continuity equation. The crystals grown by this method can be used for construction of the vary-zone structures

  9. Growth of ZnO nanowire arrays directly onto Si via substrate topographical adjustments using both wet chemical and dry etching methods

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Nathan A., E-mail: 523615@swansea.ac.uk [Centre for Nanohealth, Department of Physics, College of Science, University of Swansea, Singleton Park SA2 8PP United Kingdom (United Kingdom); Evans, Jon E.; Jones, Daniel R. [Multidisciplinary Nanotechnology Centre, College of Engineering, University of Swansea, Singleton Park, SA2 8PP United Kingdom (United Kingdom); Lord, Alex M. [Centre for Nanohealth, College of Engineering, University of Swansea, Singleton Park, SA2 8PP United Kingdom (United Kingdom); Wilks, S.P. [Centre for Nanohealth, Department of Physics, College of Science, University of Swansea, Singleton Park SA2 8PP United Kingdom (United Kingdom)

    2015-03-15

    Highlights: • Arrays of catalyst-free ZnO NWs have been grown by CVD without seed layers on Si. • Si surface topography was altered by substrate etching, resulting in NW growth. • XPS analysis shows growth is related to topography and not surface contamination. • Using e-beam lithography with etching, selective nanowire growth is demonstrated. • Electrical measurements on the arrays show improved conduction through the Si. - Abstract: Arrays of CVD catalyst-free ZnO nanowires have been successfully grown without the use of seed layers, using both wet chemical and dry plasma etching methods to alter surface topography. XPS analysis indicates that the NW growth cannot be attributed to a substrate surface chemistry and is therefore directly related to the substrate topography. These nanowires demonstrate structural and optical properties typical of CVD ZnO nanowires. Moreover, the NW arrays exhibit a degree of vertical alignment of less than 20° from the substrate normal. Electrical measurements suggest an improved conduction path through the substrate over seed layer grown nanowires. Furthermore, the etching technique was combined with e-beam lithography to produce high resolution selective area nanowire growth. The ability to pattern uniform nanowires using mature dry etch technology coupled with the increased charge transport through the substrate demonstrates the potential of this technique in the vertical integration of nanowire arrays.

  10. Growth and accumulation of flavan-3-ol in Camellia sinensis through callus culture and suspension culture method

    Directory of Open Access Journals (Sweden)

    Sutini Sutini

    2017-02-01

    Full Text Available This study was aimed to assess flavan-3-ol biomass in C. sinensis through callus cultures and suspension cultures derived from leaf explants. Callus initiation of both cultures were using Murashige and Skoog medium were enriched with plant growth regulators Naphtha-lene Acetic Acid 3.0 mg/L and kinetin 2.0 mg/L. The procedures in this study were: (1 callus initiation by cutting the leaves of C. sinen-sis shoots then planted on Murashige and Skoog medium that were enriched with plant growth regulators, (2 sub callus culture on fresh medium that enriched with the same growth regulators, (3 suspension culture initiation of liquid callus, (4 growth examination of callus and suspension cultures in week 12, (5 examination of qualitative-quantitative content of flavan-3-olin suspension cultures at week 4. The results show that suspension cultures contain biomass flavan-3-ol that increase in the same manner of the increase of callus age and weight

  11. Validity of the tritiated thymidine method for estimating bacterial growth rates: measurement of isotope dilution during DNA synthesis

    International Nuclear Information System (INIS)

    Pollard, P.C.; Moriarty, D.J.W.

    1984-01-01

    The rate of tritiated thymidine incorporation into DNA was used to estimate bacterial growth rates in aquatic environments. To be accurate, the calculation of growth rates has to include a factor for the dilution of isotope before incorporation. The validity of an isotope dilution analysis to determine this factor was verified in experiments reported here with cultures of a marine bacterium growing in a chemostat. Growth rates calculated from data on chemostat dilution rates and cell density agreed well with rates calculated by tritiated thymidine incorporation into DNA and isotope dilution analysis. With sufficiently high concentrations of exogenous thymidine, de novo synthesis of deoxythymidine monophosphate was inhibited, thereby preventing the endogenous dilution of isoope. The thymidine technique was also shown to be useful for measuring growth rates of mixed suspensions of bacteria growing anaerobically. Thymidine was incorporated into the DNA of a range of marine pseudomonads that were investigated. Three species did not take up thymidine. The common marine cyanobacterium Synechococcus species did not incorporate thymidine into DNA

  12. Diagnostic reliability of the cervical vertebral maturation method and standing height in the identification of the mandibular growth spurt.

    Science.gov (United States)

    Perinetti, Giuseppe; Contardo, Luca; Castaldo, Attilio; McNamara, James A; Franchi, Lorenzo

    2016-07-01

    To evaluate the capability of both cervical vertebral maturation (CVM) stages 3 and 4 (CS3-4 interval) and the peak in standing height to identify the mandibular growth spurt throughout diagnostic reliability analysis. A previous longitudinal data set derived from 24 untreated growing subjects (15 females and nine males,) detailed elsewhere were reanalyzed. Mandibular growth was defined as annual increments in Condylion (Co)-Gnathion (Gn) (total mandibular length) and Co-Gonion Intersection (Goi) (ramus height) and their arithmetic mean (mean mandibular growth [mMG]). Subsequently, individual annual increments in standing height, Co-Gn, Co-Goi, and mMG were arranged according to annual age intervals, with the first and last intervals defined as 7-8 years and 15-16 years, respectively. An analysis was performed to establish the diagnostic reliability of the CS3-4 interval or the peak in standing height in the identification of the maximum individual increments of each Co-Gn, Co-Goi, and mMG measurement at each annual age interval. CS3-4 and standing height peak show similar but variable accuracy across annual age intervals, registering values between 0.61 (standing height peak, Co-Gn) and 0.95 (standing height peak and CS3-4, mMG). Generally, satisfactory diagnostic reliability was seen when the mandibular growth spurt was identified on the basis of the Co-Goi and mMG increments. Both CVM interval CS3-4 and peak in standing height may be used in routine clinical practice to enhance efficiency of treatments requiring identification of the mandibular growth spurt.

  13. Effects of Tillage Methods on Some Soil Physical Properties, Growth and Yield of Water Melon in a Semi-Arid Region of Nigeria

    Directory of Open Access Journals (Sweden)

    A. Dauda

    2017-02-01

    Full Text Available An appropriate tillage method is necessary to create an optimum seed bed condition for optimum crop growth and yield. Two-year field experiment was conducted in 2013 and 2014 to investigate the effects of different tillage methods on the physical properties of sandy loam soil, growth and yield of water melon (Citrullus vulgaris in a semi-arid environment. The Tillage treatments were disc ploughing plus disc harrowing (DP+DH, double disc ploughing (DDP, double disc harrowing (DDH, disc ploughing (DP and disc harrowing (DH as minimum tillage (MT and zero tillage (ZT and direct drilling method (control. The watermelon seeds were Planted manually placing three (3 seeds per hole at an interval of 1.5m along the rows and 50cm between the rows at an average depth of 5cm. The treatments were laid in a randomized complete block design (RCBD with four replications. Results showed that disc ploughing + disc harrowing (DP+DH was found to be more appropriate and profitable tillage method in improving soil physical properties and growth and yield of water melon in a sandy loam soil. Watermelon yield, fruit weight (FW, fruit length (FL, fruit diameter (FD and leaf area index (LAI were significantly influenced (P=0.05, but influence of tillage treatments were not significant on the number of fruit per plant (NFPP. A numerical value of 31.0t/ha, 26.0, 5.4kg, 29.0cm, and 33.8cm were recorded for maximum crop yield, NFPP, FW, FD and FL respectively in DP+DH-treated plots. For zero tillage (ZT treatment, maximum of crop yield and NFPP were 26.5t/ha and 20.0 respectively. Thus for enhanced growth and yield of watermelon, DP/DH would be more preferable. The orthodox method of zero tillage is out rightly discouraged

  14. Cathodoluminescence of GaN diped with Zn in the process of epitaxial growth and by the method of ionic implantation

    International Nuclear Information System (INIS)

    Khasanov, I.Sh.; Gippius, A.A.; Kuznetsov, A.V.; Petrov, M.N.; Sletov, M.M.

    1984-01-01

    The cathodoluminescence (CL) method was used to investigate the epitaxial GaN layers doped with Zn both in the process of growth and by the method of ionic implantation for the purpose of clarifying the effect of doping technique on impurity luminescence. It was shown that (2-3)x10 18 cm -3 concentration is optimal with respect to intensity of impurity ''blue'' luminescence for gallium nitride doped with Zn. The intensity of GaN ''blue'' luminescence during Zn ionic implantation is several times lower as compared with doping in the process of growth. This is related to incomplete optical activation of impurity atoms in the process of postimplantation thermal annealing. Increase of zinc concentration above optimal during ionic implantation intensifies crystal lattice disordering, which is supported by intensification of 1.7 eV cathodoluminescence band in spectra conditioned by defects

  15. Nitrogen-doping effects on the growth, structure and electrical performance of carbon nanotubes obtained by spray pyrolysis method

    Energy Technology Data Exchange (ETDEWEB)

    Ionescu, Mihnea Ioan; Zhang Yong; Li Ruying [Department of Mechanical and Materials Engineering, University of Western Ontario, London, ON N6A 5B9 (Canada); Abou-Rachid, Hakima [Defense Research and Development Canada - Valcartier, 2459 Boulevard PieXI Nord, Quebec, QC G3J 1X5 (Canada); Sun Xueliang, E-mail: xsun@eng.uwo.ca [Department of Mechanical and Materials Engineering, University of Western Ontario, London, ON N6A 5B9 (Canada)

    2012-03-01

    Vertically aligned nitrogen-doped carbon nanotubes (CNTs) with modulated nitrogen content have been synthesized in a large scale by using spray pyrolysis chemical vapor deposition technique. The effects of nitrogen doping on the growth, structure and electrical performance of carbon nanotubes have been systematically examined. Field emission scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, and Raman techniques have been employed to characterize the morphology, composition, and vibrational properties of nanotubes. The results indicate that the nitrogen incorporation significantly influences the growth rate, morphology, size and structure of nanotubes. Electrical measurement investigation of the nanotubes indicates that the change in electrical resistance increases with temperature and pressure as the nitrogen concentration increases inside the tubes. This work presents a versatile, safe, and easy way to scale up route of growing carbon nanotubes with controlled nitrogen content and modulated structure, and may provide an insight in developing various nitrogen-doped carbon-based nanodevices.

  16. An empirical investigation on different methods of economic growth rate forecast and its behavior from fifteen countries across five continents

    Science.gov (United States)

    Yin, Yip Chee; Hock-Eam, Lim

    2012-09-01

    Our empirical results show that we can predict GDP growth rate more accurately in continent with fewer large economies, compared to smaller economies like Malaysia. This difficulty is very likely positively correlated with subsidy or social security policies. The stage of economic development and level of competiveness also appears to have interactive effects on this forecast stability. These results are generally independent of the forecasting procedures. Countries with high stability in their economic growth, forecasting by model selection is better than model averaging. Overall forecast weight averaging (FWA) is a better forecasting procedure in most countries. FWA also outperforms simple model averaging (SMA) and has the same forecasting ability as Bayesian model averaging (BMA) in almost all countries.

  17. Dentoalveolar growth of patients with complete unilateral cleft lip and palate by early two-stage furlow and push-back method: preliminary results.

    Science.gov (United States)

    Kitagawa, Taiji; Kohara, Hiroshi; Sohmura, Taiji; Takahashi, Junzo; Tachimura, Takashi; Wada, Takeshi; Kogo, Mikihiko

    2004-09-01

    This study examined dentoalveolar growth changes prior to the time of palatoplasty up to 3 years of age by the early two-stage Furlow and push-back methods. Thirty-four Japanese patients with complete unilateral cleft lip and palate (UCLP) treated with either a two-stage Furlow procedure (Furlow group: seven boys, eight girls) from 1998 to 2002 or a push-back procedure (push-back group; 12 boys, 7 girls) from 1993 to 1997. Consecutive plaster models were measured by three-dimensional laser scanner, before primary palatoplasty, before hard palate closure (Furlow group only), and at 3 years of age. Bite measures were taken at 3 years of age. In the Furlow group, arch length, canine width, first and second deciduous molar width and cross-sectional area, and depth and volume at midpoint showed greater growth than in the push-back group. In the Furlow group, the crossbite score was also better than in the push-back group at 3 years of age. In comparison with the push-back group, inhibition of growth impediment in the anterior region was observed in the horizontal direction in the Furlow group. In the midregion, it was observed in the horizontal and vertical directions, and in the posterior region it was observed in the horizontal direction. The results demonstrate that the early two-stage Furlow method showed progressive alveolar growth. Therefore, the early two-stage Furlow method is a more beneficial procedure than the push-back method.

  18. Inter-lab comparison of precision and recommended methods for age estimation of Florida manatee (Trichechus manatus latirostris) using growth layer groups in earbones

    OpenAIRE

    Brill, Katherine; Marmontel, Miriam; Bolen-Richardson, Meghan; Stewart, Robert EA

    2016-01-01

    Manatees are routinely aged by counting Growth Layer Groups (GLGs) in periotic bones (earbones). Manatee carcasses recovered in Florida between 1974 and 2010 provided age-estimation material for three readers and formed the base for a retrospective analysis of aging precision (repeatability). All readers were in good agreement (high precision) with the greatest apparent source of variation being the result of earbone remodelling with increasing manatee age. Over the same period, methods of sa...

  19. Pretreatment of clinical specimens with sodium dodecyl (lauryl) sulfate is not suitable for the mycobacteria growth indicator tube cultivation method.

    OpenAIRE

    Pfyffer, G E; Welscher, H M; Kissling, P

    1997-01-01

    When using the Mycobacteria Growth Indicator Tube (MGIT), pretreatment of clinical specimens with N-acetyl-L-cysteine-NaOH is recommended by the manufacturer. Processing of clinical specimens (n = 1,000) with sodium dodecyl (lauryl) sulfate-NaOH resulted in both poor recovery and delayed mean time to detection of acid-fast bacilli. Values were comparable to those obtained on solid media.

  20. Life cycle and population growth rate of Caenorhabditis elegans studied by a new method

    OpenAIRE

    Schroeder Fabian; Muschiol Daniel; Traunspurger Walter

    2009-01-01

    Abstract Background The free-living nematode Caenorhabditis elegans is the predominant model organism in biological research, being used by a huge number of laboratories worldwide. Many researchers have evaluated life-history traits of C. elegans in investigations covering quite different aspects such as ecotoxicology, inbreeding depression and heterosis, dietary restriction/supplement, mutations, and ageing. Such traits include juvenile growth rates, age at sexual maturity, adult body size, ...

  1. The growth of GaN films by alternate source gas supply hot-mesh CVD method

    Energy Technology Data Exchange (ETDEWEB)

    Komae, Yasuaki; Saitou, Takeshi [Nagaoka University of Technology, Nagaoka 940-2188 (Japan); Suemitsu, Maki; Ito, Takashi [Center of Interdisciplinary Research, Tohoku University, Sendai 980-8578 (Japan); Endoh, Tetsuo [Research Institute of Electrical Communication, Tohoku University, Sendai 980-8577 (Japan); Nakazawa, Hideki [Faculty of Science and Technology, Hirosaki University, Hirosaki 036-8561 (Japan); Narita, Yuzuru [Faculty of Engineering, Yamagata University, Yonezawa 992-8510 (Japan); Takata, Masasuke; Akahane, Tadashi [Nagaoka University of Technology, Nagaoka 940-2188 (Japan); Yasui, Kanji, E-mail: kyasui@vos.nagaokaut.ac.j [Nagaoka University of Technology, Nagaoka 940-2188 (Japan)

    2009-04-30

    Gallium nitride (GaN) films and Aluminium nitride (AlN) layers were deposited on SiC/Si (111) substrates by an alternating source gas supply or an intermittent supply of a source gas such as ammonia (NH{sub 3}), trimethylgallium (TMG) or trimethylaluminum (TMA) in a hot-mesh chemical vapor deposition (CVD) apparatus. The AlN layer was deposited as a buffer layer using NH{sub 3} and TMA on a SiC layer grown by carbonization on Si substrates using propane (C{sub 3}H{sub 8}). GaN films were grown on an AlN layer by a reaction between NH{sub x} radicals generated on a ruthenium (Ru) coated tungsten (W)-mesh and TMG molecules. An alternating source gas supply or an intermittent supply of one of the source gases during the film growth are expected to be effective for the suppression of gas phase reactions and for the enhancement of precursor migration on the substrate surface. By the intermittent supply of alkylmetal gas only during the growth of the AlN layer, the defect generation in the GaN films was reduced. GaN film growth by intermittent supply on an AlN buffer layer, however, did not lead to the improvement of the film quality.

  2. Grain growth behavior of Li{sub 4}SiO{sub 4} pebbles fabricated by agar method for tritium breeder

    Energy Technology Data Exchange (ETDEWEB)

    Xiang, Maoqiao [School of Materials Science and Engineering, University of Science and Technology Beijing, 30 Xueyuan Road, Haidian District, Beijing 100083 (China); Zhang, Yingchun, E-mail: zycustb@126.com [School of Materials Science and Engineering, University of Science and Technology Beijing, 30 Xueyuan Road, Haidian District, Beijing 100083 (China); Zhang, Yun; Wang, Chaofu; Liu, Wei [School of Materials Science and Engineering, University of Science and Technology Beijing, 30 Xueyuan Road, Haidian District, Beijing 100083 (China); Yu, Yonghong [Department of Physics, Renmin University of China, Beijing, 100872 (China)

    2016-11-15

    Highlights: • Grain sizes of Li{sub 4}SiO{sub 4} were adjusted by different silicon sources. • Grain growth exponent of Li{sub 4}SiO{sub 4} was about 3. • Grain growth activation energy of Li{sub 4}SiO{sub 4} was about 125.54 kJ/mol. • Grain growth of Li{sub 4}SiO{sub 4} pebble was controlled by vapor transport. - Abstract: The Li{sub 4}SiO{sub 4} tritium breeding pebbles will be filled in the blanket and used for 2 years or more at high temperatures, which would increase the grain size and affect tritium release. Hence, grain sizes of the Li{sub 4}SiO{sub 4} pebbles fabricated by agar method were investigated, and two kinds of different silicon sources (crystal and amorphous SiO{sub 2}) with different particle sizes were used. The particle size of SiO{sub 2} could affect grain size and density of the Li{sub 4}SiO{sub 4} pebble. And the isothermal sintering was carried out to study the grain growth kinetics of Li{sub 4}SiO{sub 4}. The grain growth exponent (n) and the activation energy (Q) were calculated by the phenomenological kinetic equation. The calculated n values were 4.10, 3.98, 3.34 and 2.96, and corresponding Q values were 152.15, 147.99, 125.54 and 110.58 kJ/mol, respectively. At the higher sintering temperatures (950 and 1000 °C), the grain growth of Li{sub 4}SiO{sub 4} was controlled by vapor transport.

  3. A cellular automaton - finite volume method for the simulation of dendritic and eutectic growth in binary alloys using an adaptive mesh refinement

    Science.gov (United States)

    Dobravec, Tadej; Mavrič, Boštjan; Šarler, Božidar

    2017-11-01

    A two-dimensional model to simulate the dendritic and eutectic growth in binary alloys is developed. A cellular automaton method is adopted to track the movement of the solid-liquid interface. The diffusion equation is solved in the solid and liquid phases by using an explicit finite volume method. The computational domain is divided into square cells that can be hierarchically refined or coarsened using an adaptive mesh based on the quadtree algorithm. Such a mesh refines the regions of the domain near the solid-liquid interface, where the highest concentration gradients are observed. In the regions where the lowest concentration gradients are observed the cells are coarsened. The originality of the work is in the novel, adaptive approach to the efficient and accurate solution of the posed multiscale problem. The model is verified and assessed by comparison with the analytical results of the Lipton-Glicksman-Kurz model for the steady growth of a dendrite tip and the Jackson-Hunt model for regular eutectic growth. Several examples of typical microstructures are simulated and the features of the method as well as further developments are discussed.

  4. Low-angled peripheral intravenous catheter tip placement decreases phlebitis.

    Science.gov (United States)

    Tanabe, Hidenori; Murayama, Ryoko; Yabunaka, Koichi; Oe, Makoto; Takahashi, Toshiaki; Komiyama, Chieko; Sanada, Hiromi

    2016-11-02

    Peripheral intravenous catheters (PIVCs) are frequently removed due to phlebitis. We hypothesized that catheters made of polyurethane, which is more flexible than Teflon, would decrease phlebitis, and that flexibility could be estimated by measuring the catheter-tip angle. Ultrasonography in two groups of patients with different catheter types was then used to compare catheter-tip angles and phlebitis. Observational studies were carried out at a medical ward in a university hospital. Infusion therapy was administered to one group of patients in 2014 using Teflon catheters (control group, n = 200), and to another group of patients in 2015 using polyurethane catheters (investigational group, n = 207). The symptoms were assessed according to a scale developed by the Infusion Nurses Society. Long-axis ultrasonography images taken immediately before catheter removal were used to measure the angle between the central line of the catheter within 2 mm from the distal point and a tangent to the vessel wall. There were no significant differences between the two groups with respect to sex, age, and medical diagnosis. In the control and investigational groups, the rates of phlebitis were 37% (73/200) and 17% (36/207), respectively (pPhlebitis occurred more frequently when the catheter-tip was placed at angle >5.8°. The frequency of phlebitis was lower in the polyurethane, in which the catheter was placed at lower angle, almost parallel to the vessel. Our results will aid in developing new catheters and in improving PIVC-securement techniques.

  5. GALAXI: Gallium anode low-angle x-ray instrument

    Directory of Open Access Journals (Sweden)

    Emmanuel Kentzinger

    2016-03-01

    Full Text Available The high brilliance laboratory small angle X-ray scattering instrument GALAXI, which is operated by JCNS, Forschungszentrum Jülich, permits the investigation of chemical correlations in bulk materials or of structures deposited on a surface at nanometre and mesoscopic length scales. The instrument is capable to perform GISAXS experiments in reflection at grazing incidence as well as SAXS experiments in transmission geometry. The X-ray flux on sample is comparable or higher than the one obtained at a comparable beamline at a second generation synchrotron radiation source.

  6. The use of 32P Method to Evaluate the Growth of Lowland Rice Cultivated in a System of Rice Intensification (SRI

    Directory of Open Access Journals (Sweden)

    A. Citraresmini

    2013-08-01

    Full Text Available A pot experiment has been conducted to evaluate the growth of the Dyah Suci, a lowland rice variety, in an SRI (System of Rice Intensification planting system. The phosphorus-32 (32P isotope technique was used to evaluate the growth of plants in relation with their phosphorus uptake. The uptake was assumed to vary in the same direction as the growth of the plant. The 32P uptake is assumed to vary in the opposite direction to the plant’s total phosphorus uptake. Here the 32P uptake is expressed in count per minutes (cpm which is then transformed to disintegration per minute (dpm. The results show that, in terms of promoting the plant’s uptake of phosphorus, the SRI planting system is superior to the conventional planting system, and it is manifested in the higher dry weight of straw and grain. From this experiment it is concluded that the 32P method can be used satisfactorily as a tool for explaining the relation between P-uptake and plant growth

  7. Study of Effects of Time, Quantity and Application Method of Benzylaminopurine and Gibberellic Acid Growth Regulators on Breaking Seed Dormancy of Kelussia odoratissima M.

    Directory of Open Access Journals (Sweden)

    S. Zafarian

    2013-06-01

    Full Text Available Karafs Kouhi (Kelussia odoratissima M. is one of the important medicinal plants of umbelliferae family and native of Zagros Mountains range, which is endangered due to illegal harvests. In order to accelerate breaking the seed dormancy of this plant, a factorial experiment based on completely randomized design with four replications, was carried in Faculty of Agriculture, Shahrekord University. The seeds of Karafs Kouhi from Saraghaseyed ecotype were treated under three time periods (25, 50, 75 and 100 days after planting, combination of enzylaminopurine (BAP (concentrations of 0, 0.75 and 1.5 mg/L and gibberellic acid (GA3 (concentrations of 0, 250 and 500 mg/L and application methods of these growth regulators (soaking seeds in the growth regulators and use of growth regulators directly on the medium. In this experiment, germination percentage, rootlet length and hypocotyl length were studied. The results indicated that 100 days after planting significantly (P≥0.01 showed the highest rates in the three studied traits. In this treatment, the germination percentage was 86.94%, rootlet length was 9.43 cm and hypocotyl length was 11.64 cm. Moreover, the interaction of the factors was not significant for all the traits. The best combination to increase germination percent, rootlet length and germination rate, was 0.75 mg/L BAP, 500 mg/L GA3 and direct use of growth regulators. To increase hypocotyl length, only 500 mg/L GA3 is recommended.

  8. Impact of the Great East Japan Earthquake on feeding methods and newborn growth at 1 month postpartum: results from the Fukushima Health Management Survey

    International Nuclear Information System (INIS)

    Kyozuka, Hyo; Yasuda, Shun; Kawamura, Makoto; Nomura, Yasuhisa; Fujimori, Keiya; Goto, Aya; Yasumura, Seiji; Abe, Masafumi

    2016-01-01

    This study examined the effects of three disasters (the Great East Japan Earthquake of March 11, 2011, followed by a tsunami and the Fukushima Daiichi Nuclear Power Plant accident) on feeding methods and growth in infants born after the disasters. Using results from the Fukushima Health Management Survey, Soso District (the affected area where the damaged nuclear power plant is located) and Aizu District (a less-affected area located farthest from the plant) were compared. In this study, newborn and maternal background characteristics were examined, as well as feeding methods, and other factors for newborn growth at the first postpartum examination for 1706 newborns born after the disaster in the affected (n = 836) and less-affected (n = 870) areas. Postpartum examinations took place 1 month after birth. Feeding method trends were examined, and multivariate regression analyses were used to investigate effects on newborn mass gain. There were no significant differences in background characteristics among newborns in these areas. When birth dates were divided into four periods to assess trends, no significant change in the exclusive breastfeeding rate was found, while the exclusive formula-feeding rate was significantly different across time periods in the affected area (p = 0.02). Multivariate analyses revealed no significant independent associations of maternal depression and change in medical facilities (possible disaster effects) with other newborn growth factors in either area. No area differences in newborn growth at the first postpartum examination or in exclusive breastfeeding rates were found during any period. Exclusive formula-feeding rates varied across time periods in the affected, but not in the less-affected area. It is concluded that effective guidance to promote breast-feeding and prevent exclusive use of formula is important for women in post-disaster circumstances. (orig.)

  9. Impact of the Great East Japan Earthquake on feeding methods and newborn growth at 1 month postpartum: results from the Fukushima Health Management Survey

    Energy Technology Data Exchange (ETDEWEB)

    Kyozuka, Hyo; Yasuda, Shun; Kawamura, Makoto; Nomura, Yasuhisa; Fujimori, Keiya [Fukushima Medical University, Department of Obstetrics and Gynecology, School of Medicine, Fukushima (Japan); Goto, Aya; Yasumura, Seiji [Radiation Medical Science Center for the Fukushima Health Management Survey, Fukushima (Japan); Fukushima Medical University, Department of Public Health, School of Medicine, Fukushima (Japan); Abe, Masafumi [Radiation Medical Science Center for the Fukushima Health Management Survey, Fukushima (Japan)

    2016-05-15

    This study examined the effects of three disasters (the Great East Japan Earthquake of March 11, 2011, followed by a tsunami and the Fukushima Daiichi Nuclear Power Plant accident) on feeding methods and growth in infants born after the disasters. Using results from the Fukushima Health Management Survey, Soso District (the affected area where the damaged nuclear power plant is located) and Aizu District (a less-affected area located farthest from the plant) were compared. In this study, newborn and maternal background characteristics were examined, as well as feeding methods, and other factors for newborn growth at the first postpartum examination for 1706 newborns born after the disaster in the affected (n = 836) and less-affected (n = 870) areas. Postpartum examinations took place 1 month after birth. Feeding method trends were examined, and multivariate regression analyses were used to investigate effects on newborn mass gain. There were no significant differences in background characteristics among newborns in these areas. When birth dates were divided into four periods to assess trends, no significant change in the exclusive breastfeeding rate was found, while the exclusive formula-feeding rate was significantly different across time periods in the affected area (p = 0.02). Multivariate analyses revealed no significant independent associations of maternal depression and change in medical facilities (possible disaster effects) with other newborn growth factors in either area. No area differences in newborn growth at the first postpartum examination or in exclusive breastfeeding rates were found during any period. Exclusive formula-feeding rates varied across time periods in the affected, but not in the less-affected area. It is concluded that effective guidance to promote breast-feeding and prevent exclusive use of formula is important for women in post-disaster circumstances. (orig.)

  10. Influence of Thawing Methods and Storage Temperatures on Bacterial Diversity, Growth Kinetics, and Biogenic Amine Development in Atlantic Mackerel

    DEFF Research Database (Denmark)

    Onyang, S.; Palmadottir, H.; Tomason, T.

    2016-01-01

    Limited knowledge is currently available on the influence of fish thawing and subsequent storage conditions on bacterial growth kinetics, succession, and diversity alongside the production of biogenic amines. This study aimed to address these factors during the thawing and subsequent storage of m...... amine producing bacteria, with the exception of the genus Proteus, which was 8.6% in fast-thawed mackerel during storage at ambient temperature. This suggests that the decarboxylation potential is dependent on both microbial load and microbial community structure....

  11. Study on method and mechanism of deep well circulation for the growth control of Microcystis in aquaculture pond.

    Science.gov (United States)

    Cong, Haibing; Sun, Feng; Wu, Jun; Zhou, Yue; Yan, Qi; Ren, Ao; Xu, Hu

    2017-06-01

    In order to control the growth of Microcystis in aquaculture ponds and reduce its adverse effect on water quality and aquaculture, a production-scale experiment of deep well circulation treatment was carried out in an aquaculture pond with water surface area of 63,000 m 2 and water depth of 1.6-2.0 m. Compared with the control pond, the experiment pond had better water quality as indicated by 64.2% reduction in chlorophyll a, and 81.1% reduction in algal cells. The chemical oxygen demand, total nitrogen, and total phosphorus concentration were reduced by 55.1%, 57.5%, and 50.8%, respectively. The treatment efficiency is mainly due to the growth control of Microcystis (i.e. cell reduction of 96.4%). The gas vesicles collapsing because of the water pressure was suggested to be the mechanism for Microcystis suppression by the deep well circulation treatment. The Microcystis lost its buoyancy after gas vesicles collapsed and it settled to the bottom of the aquaculture pond. As a result, the algae reproduction was suppressed because algae could only grow in the area with enough sunlight (i.e. water depth less than 1 m).

  12. Precipitation of thin-film organic single crystals by a novel crystal growth method using electrospray and ionic liquid film

    Science.gov (United States)

    Ueda, Hiroyuki; Takeuchi, Keita; Kikuchi, Akihiko

    2018-04-01

    We report an organic single crystal growth technique, which uses a nonvolatile liquid thin film as a crystal growth field and supplies fine droplets containing solute from the surface of the liquid thin film uniformly and continuously by electrospray deposition. Here, we investigated the relationships between the solute concentration of the supplied solution and the morphology and size of precipitated crystals for four types of fluorescent organic low molecule material [tris(8-hydroxyquinoline)aluminum (Alq3), 2-(4-biphenylyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole (PBD), N,N‧-bis(3-methylphenyl)-N,N‧-diphenylbenzidine (TPD), and N,N-bis(naphthalene-1-yl)-N,N-diphenyl-benzidine (NPB)] using an ionic liquid as the nonvolatile liquid. As the concentration of the supplied solution decreased, the morphology of precipitated crystals changed from dendritic or leaf shape to platelike one. At the solution concentration of 0.1 mg/ml, relatively large platelike single crystals with a diagonal length of over 100 µm were obtained for all types of material. In the experiment using ionic liquid and dioctyl sebacate as nonvolatile liquids, it was confirmed that there is a clear positive correlation between the maximum volume of the precipitated single crystal and the solubility of solute under the same solution supply conditions.

  13. New method for the study and control of crystal growth: dilatometry under thermal gradient. Theory and application

    International Nuclear Information System (INIS)

    Potard, C.

    1975-01-01

    A new method was developed to study and control solidification processes by means of differential dilatometry. A mathematical analysis of this method is made and first results are presented. A relation is established between the variations of the volume of the sample and that of the solid obtained. The gravimetric method used for volume measurement is also mathematically analyzed. These results are applied to two solidification experiments on InSb, in strongly perturbed and controlled cooling regimes. Precisions are given on the limits of this method, and further developments towards phase transformation studies and control are envisaged [fr

  14. Effects of copper precursor concentration on the growth of cupric oxide nanorods for photoelectrode using a modified chemical bath deposition method

    Energy Technology Data Exchange (ETDEWEB)

    Oh, Hee-bong [Department of Nano Science and Engineering, High Safety Vehicle Core Technology Research Center, Inje University, Gimhae, Gyeongnam 621-749 (Korea, Republic of); Ryu, Hyukhyun, E-mail: hhryu@inje.ac.kr [Department of Nano Science and Engineering, High Safety Vehicle Core Technology Research Center, Inje University, Gimhae, Gyeongnam 621-749 (Korea, Republic of); Lee, Won-Jae [Department of Materials and Components Engineering, Dong-Eui University, Busan 614-714 (Korea, Republic of)

    2015-01-25

    Highlights: • CuO nanorod photoelectrodes were prepared by modified CBD method. • The CuO nanorods were vertically grown with a high growth rate. • Effects of precursor concentration on the CuO nanorods were investigated. - Abstract: In this study, vertically aligned CuO nanorods were grown using a modified chemical bath deposition method with various copper precursor concentrations. The morphological, structural, optical and photoelectrochemical properties of the synthesized CuO samples were characterized using a field-emission scanning electron microscope, an X-ray diffractometer, a UV–visible spectrometer and a three-electrode potentiostat, respectively. The growth rates of the samples varied from 4.3 to 500 nm/min with the varying precursor concentrations. The vertically well-grown CuO nanorods exhibited one-dimensional growth along the (0 2 0) plane. We obtained a maximum photocurrent density of −1.05 mA/cm{sup 2} at −0.6 V (vs. SCE) from the CuO nanorod photoelectrode grown using the 10 mM copper precursor concentration.

  15. [Effect of light intensity on the growth and digestive enzyme activity of juvenile sea cucumber Apostichopus japonicas under two kinds of culture methods].

    Science.gov (United States)

    Wei, Zi-Zhong; Zhao, Wen

    2014-01-01

    The effects of light intensity (0, 1000, 2000 and 3000 1x) on the growth and digestive enzyme activity of juvenile sea cucumber Apostichopus japonicus under two kinds of culture methods (compound Chinese medicine preparation and microbial preparation) were studied. Results showed that the relative mass gain rate (WGR) and the specific growth rate (SGR) of juvenile sea cucumber were significantly affected by light intensity (P sea cucumber under different light intensities were 2000 1x > 1000 1x > 3000 1x > 0 1x. Under the same light intensity, the growth of juvenile sea cucumber under the two kinds of culture methods were significantly different (P sea cucumber. The order of amylase and lipase activity was 2000 1x > 1000 1x > 3000 1x > 0 1x, while that of protease activity was 1000 1x > 2000 1x > 0 1x > 3000 1x. Under the same light intensity, the digestive enzyme activities of the Chinese medicine treatment were generally higher than those of the microbial treatment.

  16. Crystal Growth and Characterization of (Bi0.5Na0.5)TiO3-BaTiO3 Single Crystals Obtained by a Top-Seeded Solution Growth Method under High-Pressure Oxygen Atmosphere

    Science.gov (United States)

    Onozuka, Hiroaki; Kitanaka, Yuuki; Noguchi, Yuji; Miyayama, Masaru

    2011-09-01

    A single crystal of ferroelectric 0.88(Bi,Na)TiO3-0.12BaTiO3 (BNT-BT) solid solution with tetragonal P4mm structure was grown by a top-seeded solution growth (TSSG) method at a high oxygen pressure (PO2 ) of 0.9 MPa. The crystals exhibited a large remanent polarization (Pr) of 54 µC/cm2, which leads to a spontaneous polarization estimated to be 54 µC/cm2. The large Pr compared with that of crystals grown at PO2 = 0.1 MPa is suggested to originate from a low oxygen vacancy concentration. The high-PO2 TSSG method is demonstrated to be effective for obtaining large-sized, high-quality BNT-BT crystals.

  17. Application of the potential-drop method to measurements of hydrogen-induced sub-critical crack growth in zirconium-2.5 wt% niobium

    International Nuclear Information System (INIS)

    Simpson, L.A.; Clarke, C.F.

    1977-10-01

    Adaptation of the potential-drop method of crack-following to the problem of hydrogen-induced sub-critical crack growth in Zr-2.5% Nb is described. Reasons for non-linearity in the calibration of crack extension against potential drop in compact tension specimens are discussed. It is shown that despite non-linearities, careful comparison of fractographic features with the potential-drop record can lead to a continuous plot of crack velocity against time or stress intensity factor. Procedures for correcting data through temperature and load changes are also described. The application of the technique to studies of the mechanism of hydrogen crack growth is illustrated with several examples. (author)

  18. Growth of high quality Bi2Sr2CaCu2Oy single crystals by the modified vertical Bridgman method

    International Nuclear Information System (INIS)

    Nagashima, O.; Tanaka, H.; Echizen, Y.; Kishida, S.

    2004-01-01

    We grew Bi 2 Sr 2 CaCu 2 O y (Bi-2212) single crystals by the modified vertical Bridgman (VB) method, and investigated their characteristics in order to clarify the optimum growth conditions for obtaining high-quality Bi-2212 single crystals. The Bi-2212 single crystals were grown changing pulling rates or using starting materials after pre-treatments. We found that the superconducting critical temperature (T c ) of the single crystal prepared at a slow growth rate of 0.25 mm/h was about 88 K and that the single crystals were a Bi-2212 single phase. Moreover, the single crystals grown using the starting materials pre-treated in Ar and O 2 atmospheres, had the T c of about 88 and 86 K, respectively. In addition, both of single crystals were Bi-2212 single phase

  19. Ga N nano wires and nano tubes growth by chemical vapor deposition method at different NH{sub 3} flow rate

    Energy Technology Data Exchange (ETDEWEB)

    Li, P.; Liu, Y.; Meng, X. [Wuhan University, School of Physics and Technology, Key Laboratory of Artificial Micro and Nanostructures of Ministry of Education, Wuhan 430072 (China)

    2016-11-01

    Ga N nano wires and nano tubes have been successfully synthesized via the simple chemical vapor deposition method. NH{sub 3} flow rate was found to be a crucial factor in the synthesis of different type of Ga N which affects the shape and the diameter of generated Ga N nano structures. X-ray diffraction confirms that Ga N nano wires grown on Si(111) substrate under 900 degrees Celsius and with NH{sub 3} flow rate of 50 sc cm presents the preferred orientation growth in the (002) direction. It is beneficial to the growth of nano structure through catalyst annealing. Transmission electron microscopy and scanning electron microscopy were used to measure the size and structures of the samples. (Author)

  20. Methods of Monitoring Cell Fate and Tissue Growth in Three-Dimensional Scaffold-Based Strategies for In Vitro Tissue Engineering.

    Science.gov (United States)

    Leferink, Anne M; van Blitterswijk, Clemens A; Moroni, Lorenzo

    2016-08-01

    In the field of tissue engineering, there is a need for methods that allow assessing the performance of tissue-engineered constructs noninvasively in vitro and in vivo. To date, histological analysis is the golden standard to retrieve information on tissue growth, cellular distribution, and cell fate on tissue-engineered constructs after in vitro cell culture or on explanted specimens after in vivo applications. Yet, many advances have been made to optimize imaging techniques for monitoring tissue-engineered constructs with a sub-mm or μm resolution. Many imaging modalities have first been developed for clinical applications, in which a high penetration depth has been often more important than lateral resolution. In this study, we have reviewed the current state of the art in several imaging approaches that have shown to be promising in monitoring cell fate and tissue growth upon in vitro culture. Depending on the aimed tissue type and scaffold properties, some imaging methods are more applicable than others. Optical methods are mostly suited for transparent materials such as hydrogels, whereas magnetic resonance-based methods are mostly applied to obtain contrast between hard and soft tissues regardless of their transparency. Overall, this review shows that the field of imaging in scaffold-based tissue engineering is developing at a fast pace and has the potential to overcome the limitations of destructive endpoint analysis.

  1. A practical method for computation of ductile crack growth by means of finite elements and parametric 3D-modelling

    International Nuclear Information System (INIS)

    Baumjohann, F.; Kroening, J.

    1999-01-01

    The present paper originates from a contribution to the safety assessment of a reactor pressure vessel (RPV). Investigations evaluating the safety against brittle fracture (exclosure of crack initiation and arrest assessments) are completed by calculations concerning ductile crack extension. Crack geometries including the expected crack extension are generated parametrically by a computer code and are used for further calculations with finite element programs. J-integrals of ductile growing cracks located between two comparative contours are determined by interpolation. The comparative contours are loaded by instationary temperature and pressure fields and are evaluated in advance. Taking the stability condition into consideration, the ductile crack extension is determined by pursuing the equilibrium between loading and crack resistance. The automatic modelling and a mathematical program processing the finite element results evaluate the crack growth of the finite element results very effectively. (orig.)

  2. Suppression of Plesiomonas shigelloides growth in the Direct Plating method for the enumeration of Escherichia coli in water

    NARCIS (Netherlands)

    Schets FM; List C; Kadar M; de Ruiter H; Medema GJ; MGB; Water Storage Corporation Brabantse Biesbosch; Werkendam; National Institute of Hygiene; Budapest; RIZA; Lelystad

    1998-01-01

    Plesiomonas shigelloides bleek vals positieve reacties te veroorzaken in de Escherichia coli Direct Plating (DP) methode. In het hier beschreven onderzoek is geprobeerd de groei van Plesiomonas te onderdrukken door toevoeging van het vibriostaticum O/129

  3. Effect of Different Planting Methods of Onion (Allium cepa L. and Nitrogen Rate on Onion Growth Pattern under Interference with Purple Nutsedge (Cyperus rotundus

    Directory of Open Access Journals (Sweden)

    N Karimi Arpnahy

    2016-07-01

    Full Text Available Introduction Human always has looked for improving food production through increasing crops yield. In this path, weeds through competition with crop for environmental factors and inputs have reduced the quantity and quality of crop products. Competition for nitrogen absorption not only is the most common form of intra-specific competition amongst crop plants, but also is the most popular form of inter-specific competition in the system of weed-crop interference. Therefore, understanding the method of nitrogen absorption and its allocation in competing plants, will be a key tool to improve weed management strategies. Materials and Methods In order to study the effect of sowing method and nitrogen rate on the growth pattern of onion under interference with purple nutsedge, a factorial experiment based on a randomized complete block design was conducted with three replications at the Research Greenhouse of University of Birjand in 2013. The first factor included three sowing methods of onion (seed sowing, onion set and transplanting and the second factor consisted of three levels of nitrogen (50, 100 and 150 kg N ha-1, equivalent of 25, 50 and 75 mg N kg-1 soil that urea fertilizer with a purity of 46% was used for this purpose. Results and Discussion The results of the analysis of variance showed that nitrogen levels had significant effects on plant height, leaf area index as well as aboveground and bulb dry weights. Furthermore, sowing methods revealed significant effects on plant height, leaf number, leaf area index as well as aboveground and bulb dry weights. Moreover, the interaction between sowing methods and levels of nitrogen had a significant effect on plant height, leaf area index and aboveground dry weight, while it had no significant effect on leaf number and bulb dry weight. The results of the comparisons of the means of onion planting methods and nitrogen levels interactions confirmed that the superiority of the influence of onion set

  4. Inter-lab comparison of precision and recommended methods for age estimation of Florida manatee (Trichechus manatus latirostris using growth layer groups in earbones

    Directory of Open Access Journals (Sweden)

    Katherine Brill

    2016-06-01

    Full Text Available Manatees are routinely aged by counting Growth Layer Groups (GLGs in periotic bones (earbones. Manatee carcasses recovered in Florida between 1974 and 2010 provided age-estimation material for three readers and formed the base for a retrospective analysis of aging precision (repeatability. All readers were in good agreement (high precision with the greatest apparent source of variation being the result of earbone remodelling with increasing manatee age. Over the same period, methods of sample preparation and of determining a final age estimate changed. We examined the effects of altering methods on ease of reading GLGs and found no statistical differences. Accurate age estimates are an important component for effective management of the species and for better models of population trends and we summarize the currently recommended methods for estimating manatee ages using earbones.

  5. Effects of Reforestation and Site Preparation Methods on Early Growth and Survival of Scots Pine (Pinus sylvestris L. in South-Eastern Poland

    Directory of Open Access Journals (Sweden)

    Marta Aleksandrowicz-Trzcińska

    2017-11-01

    Full Text Available Successful tree regeneration is a key process in ensuring forest sustainability and one of the most crucial investments made in silviculture. This study compared the effects of three reforestation methods (planting, direct seeding, and natural regeneration and three mechanical site preparation methods (double mould-board forest plough (FP; active plough (AP; and forest mill (FM on biometric parameters, survival, and density of Scots pine (Pinus sylvestris L. seedlings in the first 4 years of growth in a clear-cut area in south-eastern Poland. Planted seedlings were higher, thicker in root collar, and had higher survival rates after the fourth growing season than trees from natural regeneration and direct seeding. Site preparation methods did not affect the density of planted seedlings. After natural regeneration and direct seeding, seedling density was lower and less homogeneous (plots with no seedlings in FM soil preparation in comparison to other methods. The survival of pines in all reforestation methods was not affected significantly by site preparation methods. Our results indicate that the best mechanical site preparation method for planting is FM, as this is the one that least disturbs the soil environment. For direct seeding the best results were achieved after AP preparation. Natural regeneration of Scots pine was most effective after FP use, and in relatively wet years also after AP use.

  6. Simulation of processes of water aerosol coagulation-condensation growth using a combination of methods of groups and fractions

    International Nuclear Information System (INIS)

    Alexander G Godizov; Alexander D Efanov; Alexander A Lukianov; Olga V Supotnitskaya

    2005-01-01

    Full text of publication follows: To describe the phenomena involving aerosol, the model in lumped parameters is used, which is based on the kinetic integral-differential equation for the function of particle distribution of size and content of soluble and insoluble impurities with sources and collision integrals. By the function of particle size distribution, the integral parameters of aerosol can be determined: water content (mass of condensed moisture in a unit of volume), dust content (mass of insoluble condensation nuclei in a unit of volume), calculational concentration and the mean radius of particles. In the aerosol transfer problem being considered, the thermodynamic fields are the external data obtained with a thermal-hydraulic computer code. For numerical simulation of the kinetic equation describing aerosol behavior in coagulation-condensation processes, a hybrid method is used, which combines the method of groups and the method of fractions. To solve the complete equation of aerosol transfer, the method of fractions is used. The integral equation describing aerosol coagulation is solved by means of the group method. The group method based on the representation of particle size distribution in terms of a linear combination of δ-functions with time-dependent arguments makes it possible to calculate the integral parameters of spectrum: the moments of distribution function at a small number of groups. The test calculations were performed by giving the particle spectrum as a lognormal distribution and Γ- function. The hybrid method combined with the thermal-hydraulic computer code enables one to simulate volume condensation of steam at varying thermal-hydraulic conditions. (authors)

  7. Driving Down HB-LED Costs. Implementation of Process Simulation Tools and Temperature Control Methods of High Yield MOCVD Growth

    Energy Technology Data Exchange (ETDEWEB)

    Quinn, William [Veeco Process Equipment, Inc., Plainview, NY (United States)

    2012-04-30

    The overall objective of this multi-faceted program is to develop epitaxial growth systems that meet a goal of 75% (4X) cost reduction in the epitaxy phase of HB-LED manufacture. A 75% reduction in yielded epitaxy cost is necessary in order to achieve the cost goals for widespread penetration of HB-LED's into back-lighting units (BLU) for LCD panels and ultimately for solid-state lighting (SSL). To do this, the program will address significant improvements in overall equipment Cost of Ownership, or CoO. CoO is a model that includes all costs associated with the epitaxy portion of production. These aspects include cost of yield, capital cost, operational costs, and maintenance costs. We divide the program into three phases where later phases will incorporate the gains of prior phases. Phase one activities are enabling technologies. In collaboration with Sandia National Laboratories we develop a Fluent-compatible chemistry predictive model and a set of mid-infrared and near-ultraviolet pyrometer monitoring tools. Where previously the modeling of the reactor dynamics were studied within FLUENT alone, here, FLUENT and Chemkin are integrated into a comprehensive model of fluid dynamics and the most advanced transport equations developed for Chemkin. Specifically, the Chemkin model offered the key reaction terms for gas-phase nucleation, a key consideration in the optimization of the MOCVD process. This new predictive model is used to design new MOCVD reactors with optimized growth conditions and the newly developed pyrometers are used monitor and control the MOCVD process temperature to within 0.5°C run-to-run and within each wafer. This portion of the grant is in collaboration with partners at Sandia National Laboratories. Phase two activities are continuous improvement projects which extend the current reactor platform along the lines of improved operational efficiency, improved systems control for throughput, and carrier modifications for increased yield

  8. Büyümenin Kaynakları Yönteminin Türkiye’deki Gözlemlerinden Esinlenen Bir Eleştirisi = A Critique of the Application of Sources of Growth Method in Turkey

    Directory of Open Access Journals (Sweden)

    Zeyyat HATİBOĞLU

    2000-01-01

    Full Text Available The source of growth approach to economic growth, which is the most widely used analysis in determining economic growth of countries, is criticized by drawing upon the recent Turkish experience. In traditional analyses, the change in relative prices of goods are totally ignored. In fact, the source of growth approach is based on the impact of the rate of growth of capital and labor inputs, each multiplied by their relative share in national income plus the rate of technical growth. The calculation of growth of the Turkish economy reveals that in 1980-1998 period, in which both input and productivity increases were higher than those in the previous period (1950-1977, the growth rate has been lower than the previous period. This has suggested that there was something wrong with the source of growth method. Thereupon, it is detected that the relative decrease of labor intensive goods prices, which accured in the second period, must have exerted a decreasing influence on the growth of national income. Whereas when the source of growth approach is used this is not visible. Again, the coincidence or necessity of a decrease in the absolute level of national income along with a decrease of the growth rate of the economy suggests that the measurement of national income by foreign exchange prices should constitute a better measurement for detecting its change over time.

  9. Extended Finite Element Method XFEM for ductile tearing: Large crack growth modelization based on the transition from a continuous medium to the crack via a cohesive zone model

    International Nuclear Information System (INIS)

    Simatos, A.

    2010-01-01

    This work extends the applicability of local models for ductile fracture to large crack growth modelization for ductile tearing. This is done inserting a cohesive zone model whose constitutive law is identified in order to be consistent with the local model. The consistency is obtained through the cohesive law incremental construction which ensures the equivalence of the energy and of the mechanical response of the models. The extension of the applicability domain of the local modelization is enabled via the XFEM framework which allows for maintaining the mechanical energy during the crack extension step. This method permits also to introduce the cohesive zone model during the calculation without regards to the mesh of the structure for its maximal tensile stress. To apply the XFEM to ductile tearing, this method is extended to non linear problems (Updated Lagrangian Formulation, large scale yield plasticity). The cohesive zone model grows when the criterion defined in term of porosity, tested at the front of the cohesive crack front, is verified. The cohesive zone growth criterion is determined in order to model most of the damaging phase with the local model to ensure that the modelization takes into account the triaxiality ratio history accurately. The proposed method is applied to the Rousselier local model for ductile fracture in the XFEM framework of Cast3M, the FE software of the CEA. (author) [fr

  10. Single crystal growth of pure and Nd-doped Y2O3 by flotating zone method with Xe arc lamp imaging furnace

    International Nuclear Information System (INIS)

    Tsuiki, H.; Kitazawa, K.; Fueki, K.; Masumoto, T.; Shiroki, K.

    1980-01-01

    Single crystals of undoped and Nd-doped yttrium oxide were grown by the floating zone method with a Xe arc lamp imaging furnace. The crystals were grown in the and directions. Transparent and subgrain-free single crystals were obtained at a growth rate of 30-60 mm/h for the undoped yttrium oxide. Facets of the cubic [100] and [211] were observed though the high temperature phase of the crystal is hexagonal. Dislocation densities of undoped yttrium oxide are given. (orig./WE)

  11. Formation of proteoglycan and collagen-rich scaffold-free stiff cartilaginous tissue using two-step culture methods with combinations of growth factors.

    Science.gov (United States)

    Miyazaki, Tatsuya; Miyauchi, Satoshi; Matsuzaka, Satoshi; Yamagishi, Chie; Kobayashi, Kohei

    2010-05-01

    Tissue-engineered cartilage may be expected to serve as an alternative to autologous chondrocyte transplantation treatment. Several methods for producing cartilaginous tissue have been reported. In this study, we describe the production of scaffold-free stiff cartilaginous tissue of pig and human, using allogeneic serum and growth factors. The tissue was formed in a mold using chondrocytes recovered from alginate bead culture and maintained in a medium with transforming growth factor-beta and several other additives. In the case of porcine tissue, the tear strength of the tissue and the contents of proteoglycan (PG) and collagen per unit of DNA increased dose-dependently with transforming growth factor-beta. The length of culture was significantly and positively correlated with thickness, tear strength, and PG and collagen contents. Tear strength showed positive high correlations with both PG and collagen contents. A positive correlation was also seen between PG content and collagen content. Similar results were obtained with human cartilaginous tissue formed from chondrocytes expanded in monolayer culture. Further, an in vivo pilot study using pig articular cartilage defect model demonstrated that the cartilaginous tissue was well integrated with surrounding tissue at 13 weeks after the implantation. In conclusion, we successfully produced implantable scaffold-free stiff cartilaginous tissue, which characterized high PG and collagen contents.

  12. The Antifungal Inhibitory Concentration Effectiveness Test From Ethanol Seed Arabica Coffee (Coffea arabica) Extract Against The Growth Of Candida albicans Patient Isolate With In Vitro Method

    Science.gov (United States)

    Satria Rakatama, Adam; Pramono, Andri; Yulianti, Retno

    2018-03-01

    Candida albicans are the most frequent cause of Vulvovaginalis Candidiasis infection. Its treatment using antifungal drugs, are oftenly caused side effects. The reduction of C.albicans growth and the reduction of antifungal drugs side effect, were our main purposed. Our study objective is determine the effectiveness of inhibitory power of arabica coffee seed ethanol extract on the growth of C.albicans patient isolates. The type of this research is experimental research. Kirby-bauer method with the Saboraud Dextrose Agar (SDA) media was used in this experiment. Inhibitory zone was observed around the disc, to determine the inhibitory power. The results showed that the inhibitory zone was formed on arabica coffee seed ethanol extract on 10%, 20%, 40%, and 80% concentration. Kruskal-Wallis test results (pthe concentration groups tested against the treatment group. The inhibitory zone was formed because of biochemical compound in arabica coffee seed such as caffeine, phenol, alkaloids, flavonoids, and saponins. Inhibitory zone in C.albicans patient isolates were smaller compared with C.albicans ATCC 90028 as gold standard. This showed that the virulence of C.albicans from patients isolates were higher. We concluded that arabica coffee seed ethanol extract could inhibiting the growth of C.albicans patient isolates. Optimization of coffee seed ethanol extract to obtain maximum active ingredients still needs to be done. This knowledge is expected to be used for the beginning manufacturer antifungal drug from natural product.

  13. Autologous method for ex vivo expansion of human limbal epithelial progenitor cells based on plasma rich in growth factors technology.

    Science.gov (United States)

    Riestra, A C; Vazquez, N; Chacon, M; Berisa, S; Sanchez-Avila, R M; Orive, G; Anitua, E; Meana, A; Merayo-Lloves, J

    2017-04-01

    Develop an autologous culture method for ex vivo expansion of human limbal epithelial progenitor cells (LEPCs) using Plasma Rich in Growth Factors (PRGF) as a growth supplement and as a scaffold for the culture of LEPCs. LEPCs were cultivated in different media supplemented with 10% fetal bovine serum (FBS) or 10% PRGF. The outgrowths, total number of cells, colony forming efficiency (CFE), morphology and immunocytochemistry against p63- α and cytokeratins 3 and 12 (CK3-CK12) were analyzed. PRGF was also used to elaborate a fibrin membrane. The effects of the scaffold on the preservation of stemness and the phenotypic characterization of LEPCs were investigated through analysis of CK3-CK12, ABCG-2 and p63. LEPCs cultivated with PRGF showed a significantly higher growth area than FBS cultures. Moreover, the number of cells were also higher in PRGF than FBS, while displaying a better morphology overall. CFE was found to be also higher in PRGF groups compared to FBS, and the p63-α expression also differed between groups. LEPCs cultivated on PRGF membranes appeared as a confluent monolayer of cells and still retained p63 and ABCG-2 expression, being negative for CK3-CK12. PRGF can be used in corneal tissue engineering, supplementing the culture media, even in a basal media without any other additives, as well as providing a scaffold for the culture. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Large and high-quality single-crystal growth of cuprate superconductor Bi-2223 using the traveling-solvent floating-zone (TSFZ) method

    Science.gov (United States)

    Adachi, Shintaro; Usui, Tomohiro; Kosugi, Kenta; Sasaki, Nae; Sato, Kentaro; Fujita, Masaki; Yamada, Kazuyoshi; Fujii, Takenori; Watanabe, Takao

    In high superconducting transition temperature (high-Tc) cuprates, it is empirically known that Tc increases on increasing the number of CuO2 planes in a unit cell n from 1 to 3. Bi-family cuprates are ideal for investigating the microscopic mechanism involved. However, it is difficult to grow tri-layered Bi-2223, probably owing to its narrow crystallization field. Here, we report improved crystal growth of this compound using the TSFZ method under conditions slightly different from those in an earlier report [J. Cryst. Growth 223, 175 (2001)]. A Bi-rich feed-rod composition of Bi2.2Sr1.9Ca2Cu3Oy and a slightly oxygen-reduced atmosphere (mixed gas flow of O2 (10%) and Ar (90%)) were adopted for the crystal growth. In addition, to increase the supersaturation of the melts, we applied a large temperature gradient along the solid-liquid interface by shielding a high-angle light beam using Al foil around the quartz tube. In this way, we succeeded in preparing large (2 × 2 × 0 . 05 mm3) and high-quality (almost 100% pure) Bi-2223 single crystals. Hirosaki University Grant for Exploratory Research by Young Scientists and Newly-appointed Scientists.

  15. Modeling of helium bubble nucleation and growth in austenitic stainless steels using an Object Kinetic Monte Carlo method

    International Nuclear Information System (INIS)

    De Backer, A.; Adjanor, G.; Domain, C.; Lescoat, M.L.; Jublot-Leclerc, S.; Fortuna, F.; Gentils, A.; Ortiz, C.J.; Souidi, A.; Becquart, C.S.

    2015-01-01

    Implantation of 10 keV helium in 316L steel thin foils was performed in JANNuS-Orsay facility and modeled using a multiscale approach. Density Functional Theory (DFT) atomistic calculations [1] were used to obtain the properties of He and He-vacancy clusters, and the Binary Collision Approximation based code MARLOWE was applied to determine the damage and He-ion depth profiles as in [2,3]. The processes involved in the homogeneous He bubble nucleation and growth were defined and implemented in the Object Kinetic Monte Carlo code LAKIMOCA [4]. In particular as the He to dpa ratio was high, self-trapping of He clusters and the trap mutation of He-vacancy clusters had to be taken into account. With this multiscale approach, the formation of bubbles was modeled up to nanometer-scale size, where bubbles can be observed by Transmission Electron Microscopy. Their densities and sizes were studied as functions of fluence (up to 5 × 10 19 He/m 2 ) at two temperatures (473 and 723 K) and for different sample thicknesses (25–250 nm). It appears that the damage is not only due to the collision cascades but is also strongly controlled by the He accumulation in pressurized bubbles. Comparison with experimental data is discussed and sensible agreement is achieved

  16. Development and improvement of measuring method for growth rate of intracellular symbiotic acid-fast bacteria using radioisotopes

    Energy Technology Data Exchange (ETDEWEB)

    Nakata, Noboru; Fukutomi, Yasuo [National Inst. for Leprosy Research, Higashimurayama, Tokyo (Japan)

    1997-02-01

    The aim of this research group was to investigate the factors which might mediate the growth of mycobacterium lepra and relate to its affinity to the nerve tissue. In this year, constructions of a mycobacterium smegmatis mutant having a high transform ability and a shuttle vector between E. coli and acid-fast bacteria was attempted. From the wild type of m. smegmatis, a highly transformable mutant was obtained and the rate of transformation of the mutant was ca. 10{sup 5} times higher than the parent. And two shuttle vectors for E. coli/acid-fast bacteria; pALKMZErO (6.2 kb) and pHSGM59 (5.4 kb) were constructed. Since the former was unstable in M. smegmatis, the latter vector was used for the following experiments. Expression of `cat` gene cloned by pHSGM59 was identified in M. smegmatis. Further, DNA library of M. leprae was prepared by the use of the vector. Approximately, 1 x 10{sup 4} transformed clones were obtained. The analysis of the plasmids recovered from the clones is under way. (M.N.)

  17. Pulsed electromagnetic field: an organic compatible method to promote plant growth and yield in two corn types.

    Science.gov (United States)

    Bilalis, Dimitrios J; Katsenios, Nikolaos; Efthimiadou, Aspasia; Karkanis, Anestis

    2012-12-01

    Pre-sowing treatment of pulsed electromagnetic fields was used in corn seeds, in both indoor and outdoor conditions, in order to investigate the effect on plant growth and yield. The results of this research showed that pulsed electromagnetic fields can enhance plant characteristics, both under controlled environmental conditions and uncontrolled field conditions. The two varieties responded differently in the duration of magnetic field. Seeds were treated for 0, 15, 30, and 45 min with pulsed electromagnetic field (MF-0, MF-15, MF-30, and MF-45). Common corn variety performed better results in MF-30 treatment, while sweet corn variety performed better in MF-45 treatment. Magnetic field improved germination percentage, vigor, chlorophyll content, leaf area, plant fresh and dry weight, and finally yields. In the very interesting measurement of yield, seeds that have been exposed to magnetic field for 30 and 45 min have been found to perform the best results with no statistical differences among them. Another interesting finding was in root dry weight measurements, where magnetic field has a negative impact in MF-30 treatment in both hybrids, however without affecting other measurements. Enhancements on plant characteristics with economic impact on producer's income could be the future of a modern, organic, and sustainable agriculture.

  18. Modeling of helium bubble nucleation and growth in austenitic stainless steels using an Object Kinetic Monte Carlo method

    Energy Technology Data Exchange (ETDEWEB)

    De Backer, A., E-mail: andree.debacker@ccfe.ac.uk [UMET, UMR 8207, Université Lille 1, Villeneuve d’Ascq (France); CCFE, Culham Centre for Fusion Energy, Abingdon, Oxon (United Kingdom); Adjanor, G.; Domain, C.; Lescoat, M.L. [EDF R& D, MMC Centre des Renardières, Moret-sur-Loing (France); Jublot-Leclerc, S.; Fortuna, F.; Gentils, A. [CSNSM, Univ Paris-Sud, CNRS/IN2P3, Orsay (France); Ortiz, C.J. [CIEMAT, Laboratorio Nacional de Fusión por Confinamiento Magnético, Madrid (Spain); Souidi, A. [Université Dr. Tahar Moulay de Saida, Saida (Algeria); Becquart, C.S. [UMET, UMR 8207, Université Lille 1, Villeneuve d’Ascq (France)

    2015-06-01

    Implantation of 10 keV helium in 316L steel thin foils was performed in JANNuS-Orsay facility and modeled using a multiscale approach. Density Functional Theory (DFT) atomistic calculations [1] were used to obtain the properties of He and He-vacancy clusters, and the Binary Collision Approximation based code MARLOWE was applied to determine the damage and He-ion depth profiles as in [2,3]. The processes involved in the homogeneous He bubble nucleation and growth were defined and implemented in the Object Kinetic Monte Carlo code LAKIMOCA [4]. In particular as the He to dpa ratio was high, self-trapping of He clusters and the trap mutation of He-vacancy clusters had to be taken into account. With this multiscale approach, the formation of bubbles was modeled up to nanometer-scale size, where bubbles can be observed by Transmission Electron Microscopy. Their densities and sizes were studied as functions of fluence (up to 5 × 10{sup 19} He/m{sup 2}) at two temperatures (473 and 723 K) and for different sample thicknesses (25–250 nm). It appears that the damage is not only due to the collision cascades but is also strongly controlled by the He accumulation in pressurized bubbles. Comparison with experimental data is discussed and sensible agreement is achieved.

  19. Nitrogen and azolla response on growth of rice plant of Mitra-I variety with SRI method

    International Nuclear Information System (INIS)

    Nurmayulis; Putra Utama; Dewi Firnia; Hasnan Yani; Ania Citraresmini

    2011-01-01

    The research was conducted in Cisadap, Bunter Village, District of Sukadana, Ciamis Regency, West Java Province from January to May 2011. This study was carried out to know the response of growth of rice plant which was fertilized by nitrogen fertilizer and Azolla michrophylla using the system of rice intensification. This research used five dozes of nitrogen fertilizer (0 %, 25 %, 50 %, 75 %, 100 %) from N 92 kg ha -1 as a recommended nitrogen fertilizer (urea 200 kg ha -1 ), and also 1,13 ton ha -1 Azolla michrophylla. The result obtained from this research showed that the application of N fertilizer at 50 % of the recommend dose (100 kg ha -1 ) with adding Azolla at a rate of 1.13 t ha -1 gave good result in the terms of plant height at 2-6 weeks after planting and number of tillers at 2-7 weeks after planting. Interaction of the 50 % N fertilizer from the recommended dose planting 1,13 t ha -1 give the highest dry weight of Azolla of plants at seven weeks after planting. (author)

  20. Low-cost growth of magnesium doped gallium nitride thin films by sol-gel spin coating method

    Science.gov (United States)

    Amin, N. Mohd; Ng, S. S.

    2018-01-01

    Low-cost sol-gel spin coating growth of magnesium (Mg) doped gallium nitride (GaN) thin films with different concentrations of Mg was reported. The effects of the Mg concentration on the structural, surface morphology, elemental compositions, lattice vibrational, and electrical properties of the deposited films were investigated. X-ray diffraction results show that the Mg-doped samples have wurtzite structure with preferred orientation of GaN(002). The crystallite size decreases and the surface of the films with pits/pores were formed, while the crystalline quality of the films degraded as the Mg concentration increases from 2% to 6. %. All the Raman active phonon modes of the wurtzite GaN were observed while a broad peak attributed to the Mg-related lattice vibrational mode was detected at 669 cm-1. Hall effect results show that the resistivity of the thin films decreases while the hole concentration and hall mobility of thin films increases as the concentration of the Mg increases.

  1. Development and improvement of measuring method for growth rate of intracellular symbiotic acid-fast bacteria using radioisotopes

    International Nuclear Information System (INIS)

    Nakata, Noboru; Fukutomi, Yasuo

    1997-01-01

    The aim of this research group was to investigate the factors which might mediate the growth of mycobacterium lepra and relate to its affinity to the nerve tissue. In this year, constructions of a mycobacterium smegmatis mutant having a high transform ability and a shuttle vector between E. coli and acid-fast bacteria was attempted. From the wild type of m. smegmatis, a highly transformable mutant was obtained and the rate of transformation of the mutant was ca. 10 5 times higher than the parent. And two shuttle vectors for E. coli/acid-fast bacteria; pALKMZErO (6.2 kb) and pHSGM59 (5.4 kb) were constructed. Since the former was unstable in M. smegmatis, the latter vector was used for the following experiments. Expression of 'cat' gene cloned by pHSGM59 was identified in M. smegmatis. Further, DNA library of M. leprae was prepared by the use of the vector. Approximately, 1 x 10 4 transformed clones were obtained. The analysis of the plasmids recovered from the clones is under way. (M.N.)

  2. Growth of Cd0.96Zn0.04Te single crystals by vapor phase gas transport method

    Directory of Open Access Journals (Sweden)

    S. H. Tabatabai Yazdi

    2006-03-01

    Full Text Available   Cd0.96Zn0.04Te crystals were grown using vapor phase gas transport method (VPGT. The results show that dendritic crystals with grain size up to 3.5 mm can be grown with this technique. X-ray diffraction and Laue back-reflection patterns show that dendritic crystals are single-phase, whose single crystal grains are randomly oriented with respect to the gas-transport axis. Electrical measurements, carried out using Van der Pauw method, show that the as-grown crystals have resistivity of about 104 Ω cm and n-type conductivity.

  3. Flight Investigation at Low Angles of Attack to Determine the Longitudinal Stability and Control Characteristics of a Cruciform Canard Missile Configuration with a Low-Aspect-Ratio Wing and Blunt Nose at Mach Numbers from 1.2 to 2.1

    Science.gov (United States)

    Brown, Clarence A , Jr

    1957-01-01

    A full- scale rocket-powered model of a cruciform canard missile configuration with a low- aspect - ratio wing and blunt nose has been flight tested by the Langley Pilotless Aircraft Research Division. Static and dynamic longitudinal stability and control derivatives of this interdigitated canard-wing missile configuration were determined by using the pulsed- control technique at low angles of attack and for a Mach number range of 1.2 to 2.1. The lift - curve slope showed only small nonlinearities with changes in control deflection or angle of attack but indicated a difference in lift- .curve slope of approximately 7 percent for the two control deflections of delta = 3.0 deg and delta= -0.3 deg . The large tail length of the missile tested was effective in producing damping in pitch throughout the Mach number range tested. The aerodynamic- center location was nearly constant with Mach number for the two control deflections but was shown to be less stable with the larger control deflection. The increment of lift produced by the controls was small and positive throughout the Mach number range tested, whereas the pitching moment produced by the controls exhibited a normal trend of reduced effectiveness with increasing Mach number.The effectiveness of the controls in producing angle of attack, lift, and pitching moment was good at all Mach numbers tested.

  4. A Post-Final Assignment for the Methods Course: Providing an Incentive to Professional Growth for Future Teachers.

    Science.gov (United States)

    Bentley, Michael L.

    This paper describes J. Rosengren's post-final assignment and M. Harmin's truth signs activity that were incorporated into a secondary science methods course for preservice teachers. The strength of the post-final assignment is that it is a strategy for extending student learning past the end of a course and even beyond the initial teaching…

  5. The liquid phase epitaxy method for the construction of oriented ZIF-8 thin films with controlled growth on functionalized surfaces

    KAUST Repository

    Shekhah, Osama; Eddaoudi, Mohamed

    2013-01-01

    Highly-oriented ZIF-8 thin films with controllable thickness were grown on an -OH-functionalized Au substrate using the liquid phase epitaxy method at room temperature, as evidenced by SEM and PXRD. The adsorption-desorption properties of the resulting ZIF-8 thin film were investigated for various VOCs using the QCM technique. © The Royal Society of Chemistry 2013.

  6. Controlled growth of epitaxial CeO2 thin films with self-organized nanostructure by chemical solution method

    DEFF Research Database (Denmark)

    Yue, Zhao; Grivel, Jean-Claude

    2013-01-01

    Chemical solution deposition is a versatile technique to grow oxide thin films with self-organized nanostructures. Morphology and crystallographic orientation control of CeO2 thin films grown on technical NiW substrates by a chemical solution deposition method are achieved in this work. Based...

  7. Influence of irrigation method and container type on Northern red oak seedling growth and media electrical conductivity

    Science.gov (United States)

    Anthony S. Davis; Douglass F. Jacobs; Ronald P. Overton; R. Kasten Dumroese

    2008-01-01

    Container production of hardwood seedlings has not been extensively practiced. Efficient nursery production of hardwood seedlings in containers can be limited by formation of a broad foliar canopy, which limits irrigation uniformity. This study was established to investigate suitability of subirrigation, a method of irrigating seedlings from the container base that...

  8. Mixed-Method Research on Learning Vocabulary through Technology Reveals Vocabulary Growth in Second-Grade Students

    Science.gov (United States)

    Huang, SuHua

    2015-01-01

    A mixed-method embedded research design was employed to investigate the effectiveness of the integration of technology for second-grade students' vocabulary development and learning. Two second-grade classes with a total of 40 students (21 boys and 19 girls) were randomly selected to participate in this study for the course of a semester. One…

  9. Method of propagation, stimulation of rhizomes growth in vitro culture and adaptation in the open ground for the genus Miscanthus representatives

    Directory of Open Access Journals (Sweden)

    С. М. Гонтаренко

    2017-09-01

    Full Text Available Purpose. To develop a method of propagation, stimulation of rhizomes growth in vitro culture for the genus Miscanthus representatives and their adaptation in the open field without the use of greenhouse complexes for acclimatization and completion of growing. Methods. Biotechnological procedures, mathematical and statistical analyses. Results. Prescription of nutrient medium was developed for explants inoculation, sprouts propagation, rhizomes growth stimulation in vitro. Such sterile explants as seeds, buds to be removed from rhizomes, parts of  stems with bud were placed on modified media with mineral portion by Murashige and Skoog (MS that contained 0,5–1 dose of macroelements and one dose of microelements,  vitamins (10 mg/l of thia­minum, 1,0 mg/l of pyridoxine, 1,0 mg/l of nicotinic acid and 1,0 mg/l of ascorbic acid supplemented with amino acids (250 mg/l of glutamic acid, 3 mg/l of tyrosine, 3 mg/l of arginine, 2 mg/l of hydroxyproline, plant growth regulators [0,5–1,0 mg/l of GA (gibberelline acid, 0,2 mg/l of 6-BAP (6-Benzylaminopurine, 0,1 mg/l of NAA (α-naphtylacetic acid] in different variations. After seed germination, buds emerging and sprouts formation 1–2 cm in height, for propagation purpose they were passivated on the medium of other composition that differed from previous one by the content and ratio of growth regulators, especially by a high concentration of cytokinins [6-BAP (0,4–0,5 mg/l, kinetin (0,5 mg/l, adenine (0,5 mg/k] in different variations in presence of GA (0,2 mg/l. In order to stimulate rhizomes growth, microclones were transferred on media with other composition and ratio growth regulators (6-BAP (0,2–0,3 mg/l + GA (0,5–1,0 mg/l or 6-BAP (0,2–0,3 mg/l + GA (0,5–1,0 mg/l + NAA (0,1 mg/l,  in other words,  with a high content of gibberellins. After the formation of rhizomes 10–15 cm in length, miscanthus plants were planted out in the open ground. Stimulation of

  10. An economical non-destructive method for estimating eelgrass, Zostera marina (Potamogetonaceae leaf growth rates: formal development and use in northwestern Baja California

    Directory of Open Access Journals (Sweden)

    Elena Solana-Arellano

    2008-09-01

    Full Text Available Seagrass beds provide much of the primary production in estuaries; host many fishes and fish larvae, and abate erosion. The present study presents original analytical methods for estimating mean leaf-growth rates of eelgrass (Zostera marina. The method was calibrated by using data collected in a Z. marina meadow at Punta Banda estuary in Baja California, Mexico. The analytical assessments were based on measurements of leaf length and standard regression procedures. We present a detailed explanation of the formal procedures involved in the derivation of these analytical methods. The measured daily leaf-growth rate was 10.9 mm d-1 leaf-1. The corresponding value projected by our method was 10.2 mm d-1 leaf-1. The associated standard errors were of 0.53 and 0.56 mm d-1 leaf-1 respectively. The method was validated by projecting leaf-growth rates from an independent data set, which gave consistent results. The use of the method to obtain the mean leaf growth rate of a transplanted plot is also illustrated. Comparison of our leaf-growth data with previously reported assessments show the significant forcing of sea-surface temperature on eelgrass leaf dynamics. The formal constructs provided here are of general scope and can be applied to equivalent eelgrass data sets in a straightforward manner. Rev. Biol. Trop. 56 (3: 1003-1013. Epub 2008 September 30.Las praderas de pastos marinos abaten la erosión y aportan gran parte de la productividad primaria de los esteros y son refugio de muchos peces y sus larvas. El presente trabajo introduce métodos analíticos para estimar las tasas medias de crecimiento foliar de Zostera marina L. y sus varianzas. La calibración del método se llevó a cabo utilizando datos de una pradera de esta fanerógama en el Estero de Punta Banda Baja California, México. Las referidas estimaciones analíticas, se basan en medias de longitud foliar y en procedimientos estandarizados de regresión. Dichas determinaciones son por

  11. Effect of castration method and analgesia on inflammation, behavior, growth performance, and carcass traits in feedlot cattle.

    Science.gov (United States)

    Roberts, S L; Powell, J G; Hughes, H D; Richeson, J T

    2018-02-15

    Our objective was to determine the effect of castration timing, method, and use of the analgesic meloxicam (MEL) on inflammation, behavior, performance, and carcass traits in feedlot cattle. This study was a randomized complete block design conducted over a 3-yr period. In total, 194 crossbred beef calves from a single ranch origin were randomized at birth to receive one of five treatments arranged as a 2 × 2 + 1 factorial: 1) bulls castrated within 48 h of birth (CON), 2) bulls surgically castrated on day 0 without MEL (SUR), 3) bulls surgically castrated on day 0 with MEL (SUR + MEL), 4) bulls band castrated on d 0 without MEL (BAN), and 5) bulls band castrated on day 0 with MEL (BAN + MEL). Upon feedlot arrival (day -11; average 287 ± 2.03 d of age), animals were blocked by initial BW (224 ± 4.5 kg) and assigned randomly to treatment pens in three consecutive years (n = 2 pens per treatment in each year). Oral MEL was administered at 1 mg/kg BW concurrent with applicable castration treatment on day 0. Data were analyzed using the MIXED and GLIMMIX procedures of SAS with pen (year) serving as experimental unit. From days 0 to 7, ADG was reduced (P = 0.01) for surgical (-0.42) compared to band (0.43 kg/d) castration. Conversely, ADG was increased for surgical (1.74) vs. band (1.46 kg/d) castration from days 14 to 32. There was also an overall (day 0 to final) improvement in ADG for MEL (P = 0.02), but no effect of castration method was observed (P = 0.81). The CON group had the greatest (P = 0.05) marbling score. Backfat thickness was increased (P = 0.01) for MEL. A treatment × day interaction (P = 0.04) existed for serum haptoglobin, with SUR having the greatest (P castrated treatment reduced (P = 0.01) serum haptoglobin concentration on day 1. Relative to baseline, standing duration for surgical castration was increased 113 min (P castration on day 0. Step count was greatest for BAN, intermediate for CON, and least for surgical (P castration, whereas

  12. Growth performance and pork fat quality as measured by three methods of pigs fed 20% DDGS and slaughtered using a standard industry split marketing strategy.

    Science.gov (United States)

    Shircliff, K E; Callahan, Z D; Wilmoth, T A; Ohman, C E; Johnson, R C; Wiegand, B R

    2015-10-01

    A total of 40 pens containing 22 crossbred barrows (initial BW = 43.07 ± 1.61 kg; PIC 1050 × PIC 337 genetics) were housed in a commercial wean to finish facility. Pens were randomly allotted to dietary treatments in a 2 × 3 factorial arrangement with 2 levels of dried distillers grains with solubles (DDGS; 0% or 20%) and chosen for 1 of 3 marketing cuts removing 4, 8, and 10 animals from each pen. Fat tissue samples were removed from the anterior tip of the jowl and posterior to the sternum on the belly edge 1d postmortem. Fatty acid composition was determined via the Folch method, and iodine values (IV) were calculated from chemical titrations, fatty acid profile (GC IV), and in-plant Bruker near-infrared (NIR) spectroscopy. Pearson's correlation coefficients for IV determination methods were estimated. Inclusion of 20% DDGS did not change ( > 0.05) growth performance, whereas marketing cut affected performance, with the second cut producing the most efficient pigs ( marketing time changed growth performance.

  13. Effects of two droplet-based dissolving microneedle manufacturing methods on the activity of encapsulated epidermal growth factor and ascorbic acid.

    Science.gov (United States)

    Huh, Inyoung; Kim, Suyong; Yang, Huisuk; Jang, Mingyu; Kang, Geonwoo; Jung, Hyungil

    2018-03-01

    Dissolving microneedle (DMN) is an attractive, minimally invasive transdermal drug delivery technology. The drugs encapsulated in the DMNs are exposed to a series of thermal, chemical, and physical stresses during the fabrication process, decreasing their therapeutic activity. Current DMN fabrication methods, such as micro-molding, drawing lithography, droplet-born air blowing, and centrifugal lithography, undergo different manufacturing processes involving differing stress conditions. Among the methods, we compared the effects of two droplet-based methods, droplet-born air blowing and centrifugal lithography, on the activity of encapsulated drugs using epidermal growth factor and ascorbic acid as model drugs. Although the appearance and physical properties of DMNs fabricated by the two methods were similar, the immunoreactivity of encapsulated epidermal growth factor in centrifugal lithography and droplet-born air blowing was 92.08±2.86% and 80.67±8.00%, respectively, at baseline, and decreased to 75.32±19.40% and 41.75±16.17%, respectively, 24h after drug-loading. The free-radical scavenging activity of ascorbic acid was maintained at 88.24±0.78% in DMNs fabricated by centrifugal lithography, but decreased over time to 67.02±1.11% in DMNs fabricated by droplet-born air blowing. These findings indicate that the manufacturing conditions of centrifugal lithography exert less stress on the drug-loaded DMNs, minimizing activity loss over time, and therefore that centrifugal lithography is suitable for fabricating DMNs loaded with fragile biological drugs. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Method

    Directory of Open Access Journals (Sweden)

    Ling Fiona W.M.

    2017-01-01

    Full Text Available Rapid prototyping of microchannel gain lots of attention from researchers along with the rapid development of microfluidic technology. The conventional methods carried few disadvantages such as high cost, time consuming, required high operating pressure and temperature and involve expertise in operating the equipment. In this work, new method adapting xurography method is introduced to replace the conventional method of fabrication of microchannels. The novelty in this study is replacing the adhesion film with clear plastic film which was used to cut the design of the microchannel as the material is more suitable for fabricating more complex microchannel design. The microchannel was then mold using polymethyldisiloxane (PDMS and bonded with a clean glass to produce a close microchannel. The microchannel produced had a clean edge indicating good master mold was produced using the cutting plotter and the bonding between the PDMS and glass was good where no leakage was observed. The materials used in this method is cheap and the total time consumed is less than 5 hours where this method is suitable for rapid prototyping of microchannel.

  15. Evaluating the Effect of Onion (Allium cepa L. Sowing Methods on Growth Characteristics of Purple Nutsedge (Cyperus rotundus L. under Different Levels of Nitrogen Fertilizer

    Directory of Open Access Journals (Sweden)

    Nosratollah Karimi Arpnahy

    2017-03-01

    Full Text Available Introduction: Increasing crop competitive ability is an important part of integrated weed management (IWM. In this regard, identifying weeds reaction to soil fertility status for developing fertilizing methods, as components of IWM programs, is a necessity. Materials and Methods: In order to evaluate the growth characteristics of purple nutsedge under the conditions of interference with onion, a factorial experiment based on randomized complete block design was conducted with three replications at the Research Greenhouse of University of Birjand in 2013. The first factor included three sowing methods of onion (seed sowing, onion set and transplanting and the second factor included three levels of nitrogen (50, 100 and 150 kg N ha-1, equivalent to 25, 50 and 75 mg N kg-1 soil, urea fertilizer with a purity of 46% was used for this purpose. Results and Discussion: The results of analysis of variance showed that sowing method and nitrogen levels had significant effects on plant height, leaf area, aboveground dry weight as well as tuber number and underground dry weights. Moreover, the interaction between sowing methods and nitrogen levels had a significant effect on plant height, leaf area, aboveground dry weight as well as tuber number and underground dry weights. The results of the comparisons of the mean for the interaction of planting methods and different levels of nitrogen indicated an increased weeds growth in direct seeding method and high levels of nitrogen in weed height trait, so that the greatest nutsedge height during the growing season (92.33 cm was obtained at direct seeding method and high nitrogen levels . Moreover, the lowest weed height during the growing season was obtained at onion set planting method and 50 kg ha-1 nitrogen. The highest leaf area of purple nutsedge at ten weeks after planting (446.65 cm2, was obtained in direct seeding method and high levels of nitrogen, and the lowest value for this trait (203.38 cm2, was

  16. Health State Monitoring of Bladed Machinery with Crack Growth Detection in BFG Power Plant Using an Active Frequency Shift Spectral Correction Method

    Directory of Open Access Journals (Sweden)

    Weifang Sun

    2017-08-01

    Full Text Available Power generation using waste-gas is an effective and green way to reduce the emission of the harmful blast furnace gas (BFG in pig-iron producing industry. Condition monitoring of mechanical structures in the BFG power plant is of vital importance to guarantee their safety and efficient operations. In this paper, we describe the detection of crack growth of bladed machinery in the BFG power plant via vibration measurement combined with an enhanced spectral correction technique. This technique enables high-precision identification of amplitude, frequency, and phase information (the harmonic information belonging to deterministic harmonic components within the vibration signals. Rather than deriving all harmonic information using neighboring spectral bins in the fast Fourier transform spectrum, this proposed active frequency shift spectral correction method makes use of some interpolated Fourier spectral bins and has a better noise-resisting capacity. We demonstrate that the identified harmonic information via the proposed method is of suppressed numerical error when the same level of noises is presented in the vibration signal, even in comparison with a Hanning-window-based correction method. With the proposed method, we investigated vibration signals collected from a centrifugal compressor. Spectral information of harmonic tones, related to the fundamental working frequency of the centrifugal compressor, is corrected. The extracted spectral information indicates the ongoing development of an impeller blade crack that occurred in the centrifugal compressor. This method proves to be a promising alternative to identify blade cracks at early stages.

  17. Optical sensing method to analyze germination rate of Capsicum annum seeds treated with growth-promoting chemical compounds using optical coherence tomography

    Science.gov (United States)

    Wijesinghe, Ruchire Eranga; Lee, Seung-Yeol; Kim, Pilun; Jung, Hee-Young; Jeon, Mansik; Kim, Jeehyun

    2017-09-01

    Seed germination rate differs based on chemical treatments, and nondestructive measurements of germination rate have become an essential requirement in the field of agriculture. Seed scientists and other biologists are interested in optical sensing technologies-based biological discoveries due to nondestructive detection capability. Optical coherence tomography (OCT) has recently emerged as a powerful method for biological and plant material discoveries. We report an extended application of OCT by monitoring the germination rate acceleration of chemically primed seeds. To validate the versatility of the method, Capsicum annum seeds were primed using three chemical compounds: sterile distilled water (SDW), butandiol, and 1-hexadecene. Monitoring was performed using a 1310-nm swept source OCT system. The results confirmed more rapid morphological variations in the seeds treated with 1-hexadecene medium than the seeds treated with SDW and butandiol within 8 consecutive days. In addition, fresh weight measurements (gold standard) of seeds were monitored for 15 days, and the obtained results were correlated with the OCT results. Thus, such a method can be used in various agricultural fields, and OCT shows potential as a rigorous sensing method for selecting the optimal plant growth-promoting chemical compounds rapidly, when compared with the gold standard methods.

  18. Health State Monitoring of Bladed Machinery with Crack Growth Detection in BFG Power Plant Using an Active Frequency Shift Spectral Correction Method.

    Science.gov (United States)

    Sun, Weifang; Yao, Bin; He, Yuchao; Chen, Binqiang; Zeng, Nianyin; He, Wangpeng

    2017-08-09

    Power generation using waste-gas is an effective and green way to reduce the emission of the harmful blast furnace gas (BFG) in pig-iron producing industry. Condition monitoring of mechanical structures in the BFG power plant is of vital importance to guarantee their safety and efficient operations. In this paper, we describe the detection of crack growth of bladed machinery in the BFG power plant via vibration measurement combined with an enhanced spectral correction technique. This technique enables high-precision identification of amplitude, frequency, and phase information (the harmonic information) belonging to deterministic harmonic components within the vibration signals. Rather than deriving all harmonic information using neighboring spectral bins in the fast Fourier transform spectrum, this proposed active frequency shift spectral correction method makes use of some interpolated Fourier spectral bins and has a better noise-resisting capacity. We demonstrate that the identified harmonic information via the proposed method is of suppressed numerical error when the same level of noises is presented in the vibration signal, even in comparison with a Hanning-window-based correction method. With the proposed method, we investigated vibration signals collected from a centrifugal compressor. Spectral information of harmonic tones, related to the fundamental working frequency of the centrifugal compressor, is corrected. The extracted spectral information indicates the ongoing development of an impeller blade crack that occurred in the centrifugal compressor. This method proves to be a promising alternative to identify blade cracks at early stages.

  19. Responses of growth of lady’s fingers ([i]Abelmoschus esculentus [/i]L. to different treatments methods of dairy wastewater

    Directory of Open Access Journals (Sweden)

    Rana Ibrahim Al-Dulaimi

    2014-03-01

    Full Text Available Introduction and objective. Water is one of the most important precious resources found on the earth, and are most often affected by anthropogenic activities and by industry. Pollution caused by human beings and industries is a serious concern throughout the world. Population growth, massive urbanization, rapid rate of industrialization and modern techniques in agriculture have accelerated water pollution and led to the gradual deterioration of its quality. A large quantity of waste water disposed of at sea or on land has caused environmental problems which have led to environmental pollution, economic losses and chemical risks caused by the wastewater, and its impact on agriculture. However, waste water which contain nutrients and organic matter has possible advantages for agricultural purposes. Therefore, the presented study was undertaken to assess the impact of Dairy Effluent (treated and untreated waste water on seed germination, seedling growth, dry matter production and the biochemical parameters of lady’s fingers ([i]Abelmoschus esculentus[/i] L.. Materials and methods. A field experiment in a green house was conducted to use raw and treated dairy wastewater for watering lady’s fingers (Abelmoschus esculentus L.. The plants were watered using (WW raw dairy wastewater, (T1 chemicals treatment, (T2 physical treatment, (T3 dilution method treatment and tap water (TW in pot experiments. Ten plants of each treatment /3 replicate were randomly selected and labelled for the collection of data. The data was collected sequentially, starting with chlorophyll content pre-harvest, vegetative qualities (shoot, root and seedling length and dry matter quality (shoot and root dry matter pos-tharvest. Results. The effect was seen on the germination seed and growth of the plant. The results showed inhibitory effect from dairy effluent (WW on seed germination and plant growth. Treatment with chemicals showed statistically significant differences with

  20. Experimental methods for screening parameters influencing the growth to product yield (Y(x/CH4 of a biological methane production (BMP process performed with Methanothermobacter marburgensis

    Directory of Open Access Journals (Sweden)

    Sébastien Bernacchi

    2014-12-01

    simple, unstructured mathematical model and experimental verification with Methanobacterium thermoautotrophicum. Biotechnol Bioeng 51: 645-658.12. Peillex JP, Fardeau ML, Belaich JP (1990 Growth of Methanobacterium thermoautotrophicum on hydrogen-carbon dioxide: high methane productivities in continuous culture. Biomass 21:315-321.13. Nishimura N, Kitaura S, Mimura A, et al. (1992 Cultivation of thermophilic methanogen KN-15 on hydrogen-carbon dioxide under pressurized conditions. J Ferment Bioeng 73: 477-480.14. Morii H, Koga Y, Nagai S (1987 Energetic analysis of the growth of Methanobrevibacter arboriphilus A2 in hydrogen-limited continuous cultures. Biotechnol Bioeng 29: 310-315.15. de Poorter LMI, Geerts WJ, Keltjens JT (2007 Coupling of Methanothermobacter thermautotrophicus methane formation and growth in fed-batch and continuous cultures under different H2 gassing regimens. Appl Environ Microbiol 73: 740-749.16. Schoenheit P, Moll J, Thauer RK (1980 Growth parameters (Ks, μmax, Ys of Methanobacterium thermoautotrophicum. Arch Microbiol 127: 59-65.17. Gerhard E, Butsch BM, Marison IW, et al. (1993 Improved growth and methane production conditions for Methanobacterium thermoautotrophicum. Appl Microbiol Biotechnol 40: 432-437.18. Seifert AH, Rittmann S, Bernacchi S, et al. (2013 Method for assessing the impact of emission gasses on physiology and productivity in biological methanogenesis. Bioresour Technol 136:747-751.19. Fardeau ML, Peillex JP, Belaich JP (1987 Energetics of the growth of Methanobacterium thermoautotrophicum and Methanococcus thermolithotrophicus on ammonium chloride and dinitrogen. Arch Microbiol 148: 128-131.20. Fardeau ML, Belaich JP (1986 Energetics of the growth of Methanococcus thermolithotrophicus. Arch Microbiol 144: 381-385.21. Morgan RM, Pihl TD, Nolling J (1997 Hydrogen regulation of growth, growth yields, and methane gene transcription in Methanobacterium thermoautotrophicum Delta H. J Bacteriol 179:889-898.22. Archer DB (1985

  1. Epitaxial growth of Er, Ti doped LiNbO3 films prepared by sol-gel method

    International Nuclear Information System (INIS)

    Takahashi, Makoto; Yoshiga, Tsuyoshi; Kajitani, Naofumi; Takeda, Yuki; Sato, Shoji; Wakita, Koichi; Ohnishi, Naoyuki; Hotta, Kazutoshi; Kurachi, Masato

    2006-01-01

    Erbium (Er 3+ ) doped lithium niobate (LiNbO 3 ) thick films were deposited on z-cut congruent LiNbO 3 (LN) substrate by the sol-gel method from the 0.20 mol/dm 3 precursor solution containing various Er 3+ concentration and 0.10 mol/dm 3 poly(vinyl alcohol) (PVA), and their crystal characteristics were evaluated. The Er 3+ concentration in the LN film was controlled by the Er 3+ concentration in the starting solution. The orientation relationships between Er doped LN films and substrates were determined by X-ray diffraction, Raman spectroscopy, and transmission electron microscopy, and (006) oriented Er doped LN epitaxial layers with parallel epitaxial relationships could be grown on the z-cut LN wafer. Moreover, it was made clear from the electron beam diffraction measurements that the film came to be polycrystalline, when the Er concentration was over 3 mol%. The refractive index of Er-doped LN films decreased with increasing Er concentration. 1.5 mol% Ti: 1.0 mol% Er LN films, which acted as a waveguide, were prepared by our so-gel method. It showed the 1530 nm emission by 980 nm excitation, which was considered to be due to the Er 3+ corresponding to the 4 I 13/2 → 4 I 15/2 transition. (author)

  2. Método simplificado para determinar el potencial de crecimiento en pacientes de Ortodoncia A simplified method to determine the potential growth in Orthodontics patients

    Directory of Open Access Journals (Sweden)

    Gladia Toledo Mayarí

    2010-06-01

    Full Text Available Se realizó una investigación de innovación tecnológica, de corte transversal, con el objetivo de presentar un método simplificado para determinar el potencial de crecimiento en pacientes tributarios de tratamiento ortodóncico, en una muestra de 150 pacientes entre 8 y 16 años, que ingresaron en la Clínica de Ortodoncia de la Facultad de Estomatología de la Habana, entre los años 2004 y 2006. A cada paciente se le realizó una radiografía de la mano izquierda y por primera vez en Cuba se estudiaron en la misma muestra, tres métodos de evaluación del potencial de crecimiento (métodos TW2, Grave y Brown, y determinación de los estadios de maduración de la falange media del tercer dedo. Una vez determinados éstos, se calcularon la correlación y la concordancia entre los mismos. Hubo altos coeficientes de correlación (hembras rho= 0,888 y varones rho= 0,921 y de concordancia (hembras Kappa= 1,000 y varones Kappa= 0,964. Se concluyó que la evaluación del potencial de crecimiento que presentaron los pacientes de Ortodoncia puede ser efectuada mediante la realización de una radiografía de la falange media del tercer dedo de la mano izquierda, lo cual constituye un útil método simplificado de evaluación.A cross-sectional technological innovation research was conducted to tender a simplified method to determine the potential growth of 150 Orthodontics patients aged between 8 and 16 admitted in the Orthodontics Clinic from the Stomatology of Ciudad de La Habana in 2004 and 2006. Each patient underwent left hand X-ray and for the first time in Cuba and in the same sample it was possible to study three assessment methods of potential growth (TW2 Method, Grave and Brown and stage determination of maturation of middle phalanx of third finger. After determination, we estimated the correlation and concordance among them, noting high correlation coefficients (rho females= 0,888 and rho= males 0,921 and of concordance (Kappa females= 1

  3. Delayed growth

    Science.gov (United States)

    ... Slow rate of growth; Retarded growth and development; Growth delay Images Toddler development References Cooke DW, Divall SA, Radovick S. Normal and aberrant growth in children. In: Melmed S, Polonsky KS, Larsen PR, ...

  4. (0 0 2-oriented growth and morphologies of ZnO thin films prepared by sol-gel method

    Directory of Open Access Journals (Sweden)

    Guo Dongyun

    2016-09-01

    Full Text Available Zinc acetate was used as a starting material to prepare Zn-solutions from solvents and ligands with different boiling temperature. The ZnO thin films were prepared on Si(1 0 0 substrates by spin-coating method. The effect of baking temperature and boiling temperature of the solvents and ligands on their morphologies and orientation was investigated. The solvents and ligands with high boiling temperature were favorable for relaxation of mechanical stress to form the smooth ZnO thin films. As the solvents and ligands with low boiling temperature were used to prepare Zn-solutions, the prepared ZnO thin films showed (0 0 2 preferred orientation. As n-propanol, 2-methoxyethanol, 2-(methylaminoethanol and monoethanolamine were used to prepare Zn-solutions, highly (0 0 2-oriented ZnO thin films were formed by adjusting the baking temperature.

  5. method

    Directory of Open Access Journals (Sweden)

    L. M. Kimball

    2002-01-01

    Full Text Available This paper presents an interior point algorithm to solve the multiperiod hydrothermal economic dispatch (HTED. The multiperiod HTED is a large scale nonlinear programming problem. Various optimization methods have been applied to the multiperiod HTED, but most neglect important network characteristics or require decomposition into thermal and hydro subproblems. The algorithm described here exploits the special bordered block diagonal structure and sparsity of the Newton system for the first order necessary conditions to result in a fast efficient algorithm that can account for all network aspects. Applying this new algorithm challenges a conventional method for the use of available hydro resources known as the peak shaving heuristic.

  6. Growth by the μ-PD Method and Visible Laser Operation of a Single-Crystal Fiber of Pr3+:KY3F10

    Directory of Open Access Journals (Sweden)

    Jun Shu

    2017-07-01

    Full Text Available We report on the first growth, spectroscopy, and visible laser operation of a single-crystal fiber (SCF of KY3F10 (KYF grown by the micro-pulling-down (μ-PD method, doped with Pr3+ ions. This material has a cubic lattice, which makes it appealing for use in the industry. However, KYF crystals are considered difficult to grow with high optical quality, even with well-established methods. Nevertheless, we grew a 50-mm-long SCF of Pr:KYF, which was transparent in its inner part. We studied the spectroscopic features of it in comparison with existing literature and with samples of the same crystal grown by the Czochralski method, and we did not notice any large differences. These characterizations confirmed that is indeed possible to grow high-quality crystals of Pr:KYF by the μ-PD method. Unfortunately, the crystal proved to be more brittle than typical KYF and especially difficult to polish, leading to rough and irregular facets, as evidenced by transmission measurements. Despite these issues, we obtained continuous-wave laser operation in the orange, red, and deep red regions, using a sample carved from the SCF as active medium and an InGaN-based laser diode as pump source, though with lower performances than in existing reports on this crystal.

  7. An Innovative Context-Based Crystal-Growth Activity Space Method for Environmental Exposure Assessment: A Study Using GIS and GPS Trajectory Data Collected in Chicago.

    Science.gov (United States)

    Wang, Jue; Kwan, Mei-Po; Chai, Yanwei

    2018-04-09

    Scholars in the fields of health geography, urban planning, and transportation studies have long attempted to understand the relationships among human movement, environmental context, and accessibility. One fundamental question for this research area is how to measure individual activity space, which is an indicator of where and how people have contact with their social and physical environments. Conventionally, standard deviational ellipses, road network buffers, minimum convex polygons, and kernel density surfaces have been used to represent people's activity space, but they all have shortcomings. Inconsistent findings of the effects of environmental exposures on health behaviors/outcomes suggest that the reliability of existing studies may be affected by the uncertain geographic context problem (UGCoP). This paper proposes the context-based crystal-growth activity space as an innovative method for generating individual activity space based on both GPS trajectories and the environmental context. This method not only considers people's actual daily activity patterns based on GPS tracks but also takes into account the environmental context which either constrains or encourages people's daily activity. Using GPS trajectory data collected in Chicago, the results indicate that the proposed new method generates more reasonable activity space when compared to other existing methods. This can help mitigate the UGCoP in environmental health studies.

  8. Growth and characterization of indium-doped Cd1−xZnxTe crystal by traveling heater method

    International Nuclear Information System (INIS)

    Wei, Gaoli; Wang, Linjun; Zhang, Jijun; Yuan, Zhenwen; Qin, Kaifeng; Min, Jiahua; Liang, Xiaoyan; Xia, Yiben

    2013-01-01

    An indium-doped detector grade Cd 0.9 Zn 0.1 Te crystal was grown by the THM technique from Te-rich solution. The as-grown crystal showed the dark resistivity of (1–3)×10 10 Ω cm. Through IR transmission microscopy Te inclusion with regular triangular or circular shapes could be observed, and the size of Te inclusion was around 7 μm and the concentration was ∼10 5 cm −3 . The impurity concentrations were greatly reduced for the THM grown CZT, as compared to the Bridgman method grown CZT. A resolution of 8.5% was achieved under the 662 keV 137 Cs gamma ray radiation at room temperature for the as-grown CZT samples. -- Highlights: ► Detector grade Cd 1−x Zn x Te has been successfully grown by the THM technique. ► The as-grown CZT has a resistivity of ∼10 10 Ω cm. ► Te inclusions' size and concentration were comparable to the commercial CZT. ► A resolution of 8.5% was achieved for the 137 Cs 662 keVgamma line

  9. Influence of growth and photocatalytic properties of copper selenide (CuSe) nanoparticles using reflux condensation method

    Energy Technology Data Exchange (ETDEWEB)

    Sonia, S. [Department of Nanoscience and Technology, Bharathiar University, Coimbatore 641046 (India); Kumar, P. Suresh [Thin Film and Nanomaterials Laboratory, Department of Physics, Bharathiar University, Coimbatore 641046 (India); Mangalaraj, D., E-mail: dmraj800@yahoo.com [Department of Nanoscience and Technology, Bharathiar University, Coimbatore 641046 (India); Ponpandian, N.; Viswanathan, C. [Department of Nanoscience and Technology, Bharathiar University, Coimbatore 641046 (India)

    2013-10-15

    Influence of reaction conditions on the synthesis of copper selenide (CuSe) nanoparticles and their photo degradation activity is studied. Nearly monodispersed uniform size (23–44 nm) nanoparticles are synthesized by varying the reaction conditions using reflux condensation method. The obtained nanoparticles are characterized by X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy and UV–visible absorption spectroscopy. The X-ray diffraction analysis of the sample shows the formation of nanoparticles with hexagonal CuSe structure. The result indicates that on increasing the reaction time from 4 to 12 h, the particle size decreases from 44 to 23 nm, but an increase in the reaction temperature increases the particle size. The calculated band gap E{sub g} is ranging from 2.34 to 3.05 eV which is blue shifted from the bulk CuSe (2.2 eV). The photocatalytic degradation efficiency of the CuSe nanoparticles on two organic dyes Methylene blue (MB) and Rhodamine-B (RhB) in aqueous solution under UV region is calculated as 76 and 87% respectively.

  10. Quantification of rat retinal growth and vascular population changes after single and split doses of proton irradiation: translational study using stereology methods

    Science.gov (United States)

    Mao, Xiao W.; Archambeau, John O.; Kubinova, Lucie; Boyle, Soames; Petersen, Georgia; Grove, Roger; Nelson, G. A. (Principal Investigator)

    2003-01-01

    This study quantified architectural and population changes in the rat retinal vasculature after proton irradiation using stereology. A 100 MeV conformal proton beam delivered 8, 14, 20 and 28 Gy as single and split doses to the whole eye. The vascular networks were prepared from retinal digests. Stereological methods were used to obtain the area of the retina and unbiased estimates of microvessel/artery/vein endothelial, pericyte and smooth muscle population, and vessel length. The retinal area increased progressively in the unirradiated, age-matched controls and in the retinas irradiated with 8 and 14 Gy, indicating uniform progressive retinal growth. No growth occurred after 20 and 28 Gy. Regression analysis of total endothelial cell number in all vessels (arteries, veins and capillaries) after irradiation documented a progressive time- and dose-dependent cell loss occurring over 15 to 24 months. The difference from controls was significant (Ppopulations after split doses. At 10 Gy, the rate of endothelial cell loss, a dose parameter used to characterize the time- and dose-dependent loss of the endothelial population, was doubled.

  11. A New Method for Re-Analyzing Evaluation Bias: Piecewise Growth Curve Modeling Reveals an Asymmetry in the Evaluation of Pro and Con Arguments.

    Directory of Open Access Journals (Sweden)

    Jens Jirschitzka

    Full Text Available In four studies we tested a new methodological approach to the investigation of evaluation bias. The usage of piecewise growth curve modeling allowed for investigation into the impact of people's attitudes on their persuasiveness ratings of pro- and con-arguments, measured over the whole range of the arguments' polarity from an extreme con to an extreme pro position. Moreover, this method provided the opportunity to test specific hypotheses about the course of the evaluation bias within certain polarity ranges. We conducted two field studies with users of an existing online information portal (Studies 1a and 2a as participants, and two Internet laboratory studies with mostly student participants (Studies 1b and 2b. In each of these studies we presented pro- and con-arguments, either for the topic of MOOCs (massive open online courses, Studies 1a and 1b or for the topic of M-learning (mobile learning, Studies 2a and 2b. Our results indicate that using piecewise growth curve models is more appropriate than simpler approaches. An important finding of our studies was an asymmetry of the evaluation bias toward pro- or con-arguments: the evaluation bias appeared over the whole polarity range of pro-arguments and increased with more and more extreme polarity. This clear-cut result pattern appeared only on the pro-argument side. For the con-arguments, in contrast, the evaluation bias did not feature such a systematic picture.

  12. Synthesis of human pancreatic growth hormone-releasing factor and two omission analogs by segment-coupling method in aqueous solution

    Energy Technology Data Exchange (ETDEWEB)

    Blake, J.; Westphal, M.; Li, C.H. (Laboratory of Molecular Endocrinology, University of California, San Francisco, USA)

    1984-01-01

    The human growth hormone-releasing factor (GRF) peptides (GlyS/sup 15/)-GRF-(1-15) (IV), trifluoroacetyl-GRF-(20-44) (VI), trifluoroacetyl-GRF-(18-44) (VIII), and trifluoroacetyl-GRF-(16-44) (X) were synthesized by the solidphase method. Each of the peptides was reacted with citraconic anhydride and the trifluoroacetyl group was removed by reaction with 10% hydrazine in water. The citraconylated GRF-(1-15) peptide was coupled to the (20-44), (18-44) or (16-44) peptides by reaction with silver nitrate/N-hydroxysuccinimide to give GRF-(1-15)-(20-44) (XII), GRF-(1-15)-(18-44) (XIII), or GRF-(1-44), respectively. GRF-(1-44) was shown to stimulate the release of rat growth hormone from rat pituitary cells with an ED/sub 50/=8.8 x 10/sup -11/M. Peptides XII and XIII were inactive, either as agonists or as antagonists of the action of GRF-(1-44).

  13. Single-crystal SrTiO3 fiber grown by laser heated pedestal growth method: influence of ceramic feed rod preparation in fiber quality

    Directory of Open Access Journals (Sweden)

    D. Reyes Ardila

    1998-10-01

    Full Text Available The rapidly spreading use of optical fiber as a transmission medium has created an interest in fiber-compatible optical devices and methods for growing them, such as the Laser Heated Pedestal Growth (LHPG. This paper reports on the influence of the ceramic feed rod treatment on fiber quality and optimization of ceramic pedestal processing that allows improvements to be made on the final quality in a simple manner. Using the LHPG technique, transparent crack-free colorless single crystal fibers of SrTiO3 (0.50 mm in diameter and 30-40 mm in length were grown directly from green-body feed rods, without using external oxygen atmosphere.

  14. Growth of (CH 3) 2NH 2CuCl 3 single crystals using evaporation method with different temperatures and solvents

    Science.gov (United States)

    Chen, L. M.; Tao, W.; Zhao, Z. Y.; Li, Q. J.; Ke, W. P.; Wang, X. M.; Liu, X. G.; Fan, C.; Sun, X. F.

    2010-10-01

    The bulk single crystals of low-dimensional magnet (CH 3) 2NH 2CuCl 3 (DMACuCl 3 or MCCL) are grown by a slow evaporation method with different kinds of solvents, different degrees of super-saturation of solution and different temperatures of solution, respectively. Among three kinds of solvent, methanol, alcohol and water, alcohol is found to be the best one for growing MCCL crystals because of its structural similarity to the raw materials and suitable evaporation rate. The best growth temperature is in the vicinity of 35 °C. The problem of the crystals deliquescing in air has been solved through recrystallization process. The crystals are characterized by means of X-ray diffraction, specific heat and magnetic susceptibility.

  15. Numerical Study of Single Bubble Growth on and Departure from a Horizontal Superheated Wall by Three-dimensional Lattice Boltzmann Method

    Science.gov (United States)

    Feng, Yuan; Li, Hui-Xiong; Guo, Kai-Kai; Zhao, Jian-Fu; Wang, Tai

    2018-05-01

    A three-dimensional hybrid lattice Boltzmann method was used to simulate the progress of a single bubble's growth and departure from a horizontal superheated wall. The evolutionary process of the bubble shapes and also the temperature fields during pool nucleate boiling were obtained and the influence of the gravitational acceleration on the bubble departure diameter (BDD), the bubble release frequency (BRF) and the heat flux on the superheated wall was analyzed. The simulation results obtained by the present three-dimensional numerical studies demonstrate that the BDD is proportional to g^{-0.301}, the BRF is proportional to g^{-0.58}, and the averaged wall heat flux is proportional to g^{0.201}, where g is the gravitational acceleration. These results are in good agreement with the common-used experimental correlations, indicating the rationality of the present numerical model and results.

  16. Growth, Structural and Optical Characterization of ZnO Nanotubes on Disposable-Flexible Paper Substrates by Low-Temperature Chemical Method

    Directory of Open Access Journals (Sweden)

    M. Y. Soomro

    2012-01-01

    Full Text Available We report the synthesis of vertically aligned ZnO nanotubes (NTs on paper substrates by low-temperature hydrothermal method. The growth of ZnO NTs on the paper substrate is discussed; further, the structural and optical properties are investigated by scanning electron microscope (SEM, transmission electron microscopy (TEM, X-ray diffraction (XRD, energy-dispersive X-ray spectroscopy (EDS, and cathodoluminescence (CL, and it was found that the ZnO NTs on paper substrate fulfill the structural and optical properties of ZnO NTs grown on other conventional substrates. This will be more beneficial in future usage of ZnO NTs in different fields and applications. Particularly, this approach opens the ways in research and development for high volume manufacturing of low-cost, flexible optoelectronics devices on disposable paper substrates and can be used in the future miniaturization trends.

  17. Implementation of a constant load method, for determination of crack growth velocities in MEX-03 system of National Institute of Nuclear Research

    International Nuclear Information System (INIS)

    Diaz S, A.; Fuentes C, P.; Merino C, F.

    2009-10-01

    Whit the objective of to complete the existent techniques for susceptibility evaluation to phenomenon of stress corrosion cracking in laboratories of Applied Sciences Area of National Institute of Nuclear Research; was realized and documented the modification of a high pressure and temperature equipment, identified as MEX-03 to carry out the implementation of a growth and crack propagation assay, using a constant load method. The assay was realized to a specimen of stainless steel AISI 304l type CT of an inch, which was previously thermally sensitize, simulating the typical degradation of this materials type below operation conditions in a BWR. The MEX-03 system, consist from an annexed auto key to a load system which originally was controlled by displacement; therefore were carried out modifications to achieve the control by load. The realized adjustments allowed to maintain a constant load during all the experiment, and as much the temperature conditions (T = 288 C) as of pressure (P = 8 Mpa) were controlled during the assay realization. The steel was exposed to a conditioned ambient with hydrogen gas addition; simulating a well-known alternative chemistry as hydrogen water chemistry that is used to mitigate the phenomenon of stress corrosion cracking, main degradation mechanism of austenitic stainless steels. The continuation of the crack behavior was realized by means of electric potential fall technique and later was validated of visual form through the fractographic analysis of cracked surface. The modification and control of equipment for realization of this experiment is necessary, for what should be carried out new assays, whose results will allow to establish the effect of dynamic and static methods in velocity determination of crack growth to laboratory level; to be considered in the existent models of crack propagation in systems and components in operation. (Author)

  18. An Evaluation of the Accuracy of the Subtraction Method Used for Determining Platelet Counts in Advanced Platelet-Rich Fibrin and Concentrated Growth Factor Preparations

    Directory of Open Access Journals (Sweden)

    Taisuke Watanabe

    2017-01-01

    Full Text Available Platelet concentrates should be quality-assured of purity and identity prior to clinical use. Unlike for the liquid form of platelet-rich plasma, platelet counts cannot be directly determined in solid fibrin clots and are instead calculated by subtracting the counts in other liquid or semi-clotted fractions from those in whole blood samples. Having long suspected the validity of this method, we herein examined the possible loss of platelets in the preparation process. Blood samples collected from healthy male donors were immediately centrifuged for advanced platelet-rich fibrin (A-PRF and concentrated growth factors (CGF according to recommended centrifugal protocols. Blood cells in liquid and semi-clotted fractions were directly counted. Platelets aggregated on clot surfaces were observed by scanning electron microscopy. A higher centrifugal force increased the numbers of platelets and platelet aggregates in the liquid red blood cell fraction and the semi-clotted red thrombus in the presence and absence of the anticoagulant, respectively. Nevertheless, the calculated platelet counts in A-PRF/CGF preparations were much higher than expected, rendering the currently accepted subtraction method inaccurate for determining platelet counts in fibrin clots. To ensure the quality of solid types of platelet concentrates chairside in a timely manner, a simple and accurate platelet-counting method should be developed immediately.

  19. Alternative methods for toxicity assessments in fish: comparison of the fish embryo toxicity and the larval growth and survival tests in zebrafish and fathead minnows.

    Science.gov (United States)

    Jeffries, Marlo K Sellin; Stultz, Amy E; Smith, Austin W; Rawlings, Jane M; Belanger, Scott E; Oris, James T

    2014-11-01

    An increased demand for chemical toxicity evaluations has resulted in the need for alternative testing strategies that address animal welfare concerns. The fish embryo toxicity (FET) test developed for zebrafish (Danio rerio) is one such alternative, and the application of the FET test to other species such as the fathead minnow (Pimephales promelas) has been proposed. In the present study, the performances of the FET test and the larval growth and survival (LGS; a standard toxicity testing method) test in zebrafish and fathead minnows were evaluated. This required that testing methods for the fathead minnow FET and zebrafish LGS tests be harmonized with existing test methods and that the performance of these testing strategies be evaluated by comparing the median lethal concentrations of 2 reference toxicants, 3,4-dicholoraniline and ammonia, obtained via each of the test types. The results showed that procedures for the zebrafish FET test can be adapted and applied to the fathead minnow. Differences in test sensitivity were observed for 3,4-dicholoraniline but not ammonia; therefore, conclusions regarding which test types offer the least or most sensitivity could not be made. Overall, these results show that the fathead minnow FET test has potential as an alternative toxicity testing strategy and that further analysis with other toxicants is warranted in an effort to better characterize the sensitivity and feasibility of this testing strategy. © 2014 SETAC.

  20. Growth and reproductive potential of Eisenia foetida (Sav) on various zoo animal dungs after two methods of pre-composting followed by vermicomposting.

    Science.gov (United States)

    Pérez-Godínez, Edmundo Arturo; Lagunes-Zarate, Jorge; Corona-Hernández, Juan; Barajas-Aceves, Martha

    2017-06-01

    Disposal of animal manure without treatment can be harmful to the environment. In this study, samples of four zoo animal dungs and one horse dung were pre-composted in two ways: (a) traditional composting and (b) bokashi pre-composting for 1month, followed by vermicomposting for 3months. The permanence (PEf) and reproductive potential (RP) of Eisenia foetida as well as the quality of vermicompost were evaluated. The PEf values and RP index of E. foetida were higher for samples pre-composted using the traditional composting method (98.7-88% and 31.85-16.27%, respectively) followed by vermicomposting (92.7-72.7% and 22.96-13.51%, respectively), when compared with those for bokashi pre-composted samples followed by vermicomposting, except for the horse dung sample (100% for both the parameters). The values of electrical conductivity (EC), cation exchange capacity (CEC), organic C, total N, available P, C/N ratio, and pH showed that both treatments achieved the norms of vermicompost (bokashi pre-composting followed by vermicomposting produced the highest values (98.7-70.7%, 97.67-96.65%, and 2.7-1.97%, respectively), when compared with the other method adapted in this study. Nevertheless, further studies with plants for plant growth evaluation are needed to assess the benefits and limitations of these two pre-composting methods prior to vermicomposting. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. In-situ Raman spectroscopy. A method to study and control the growth of microcrystalline silicon for thin-film solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Muthmann, Stefan

    2012-08-22

    This work deals with the design and application of a novel experiment, which enables in-situ Raman measurements during the parallel plate plasma enhanced chemical vapor deposition (PECVD) of {mu}cSi:H. Measurements of the crystalline volume fraction (I{sub C}{sup RS}) and the temperature of a growing film are carried out using the novel setup. To enable in-situ Raman measurement of central regions of the coated substrate in a PECVD system, optical access under normal incidence is necessary. An experimental setup in which an optical feed-through was integrated into a PECVD electrode was developed. This setup introduces a disturbance to the electrical field which sustains the plasma. By designing metallic shields the impact of the feed through was reduced considerably at low optical losses. The homogeneity of films deposited with the novel setup in different growth regimes was studied. A correlation between the magnitude of the inhomogeneity caused by the feed-through and the characteristics of the deposition regimes is found. Raman spectroscopy demands the illumination of a sample with a laser and the collection of the scattered radiation. Due to absorption of the laser light the temperature of the illuminated film is increased. Since the temperature determines the properties of a growing film the laser-induced temperature increase was studied. By pulsing the laser radiation of minimal temperature increase at maximal signal intensity was obtained. The crystalline volume fraction of a growing {mu}cSi:H layer was determined in-situ with the novel setup. A minimal temporal resolution of less than 17.5 s at sufficient signal-to-noise-ratio was achieved, which corresponds to less than 9 nm of deposited material during one measurement interval at the industrial standard growth rate of 0.5 nm/s. The obtained results were compared to depth resolved measurements which were carried out after the deposition. An excellent agreement between both methods validates the reliability

  2. Evaluation of Sowing Date, Plant Density and Harvest Method on Growth, Yield and Yield Components of Baby Corn (Zea mays L. var. SC403su

    Directory of Open Access Journals (Sweden)

    A. Rahmani

    2014-12-01

    Full Text Available Considering importance of baby corn, the study was consisted of sowing date (14th June, 3th July and 24th July as main Plots and plant densities (6.5, 8.5 and 10.5. plant m-2 as sub Plots and two harvest methods (baby corn, as first harvest sweet corn and next ear as baby corn on Growth parameter and yield of baby corn (Zea mays L. Var SC403su in agricultural Research Center and Natural Resources of Khorasan Razavi Province, Mashhad on 2009. The experiment was carried out in a factorial split plot design based on randomized completely block design with 4 replications. The results showed the highest plant height on sowing date 3thJuly with average 168.6 cm. Also the highest standard ear percentage that one of the important factors for food manufactory had on sowing date 24th July with plant density 10.5 plants plant m-2, by harvesting method baby corn with 63.9 percentages. Also The results showed the highest substandard ear percentage of baby corn was belonged to sowing date 24th July with 8.5 plant m-2, by harvesting method (baby corn sweet corn with 74.6%. The highest harvest ear index was belonged to sowing date14thJune, by harvesting method (baby corn sweet corn with 35.29 percentages. Therefore, sowing date 3thJuly for forage production with average 4 kg m-2 by harvesting method baby corn are recommended for lateral produce production. Considering to Mashhad weather conditions, producing the highest and best standard ear percentage, density, 10.5 plants per square meter and 24th July planting is recommended.

  3. Molecular beam epitaxy of GaAs nanowires and their sustainability for optoelectronic applications. Comparing Au- and self-assisted growth methods

    Energy Technology Data Exchange (ETDEWEB)

    Breuer, Steffen

    2011-09-28

    In this work the synthesis of GaAs nanowires by molecular beam epitaxy (MBE) using the vapour-liquid-solid (VLS) mechanism is investigated. A comparison between Au- and self-assisted VLS growth is at the centre of this thesis. While the Au-assisted method is established as a versatile tool for nanowire growth, the recently developed self-assisted variation results from the exchange of Au by Ga droplets and thus eliminates any possibility of Au incorporation. By both methods, we achieve nanowires with epitaxial alignment to the Si(111) substrates. Caused by differences during nanowire nucleation, a parasitic planar layer grows between the nanowires by the Au-assisted method, but can be avoided by the self-assisted method. Au-assisted nanowires grow predominantly in the metastable wurtzite crystal structure, while their self-assisted counterparts have the zincblende structure. All GaAs nanowires are fully relaxed and the strain arising from the lattice mismatch between GaAs and Si of 4.1 % is accommodated by misfit dislocations at the interface. Self-assisted GaAs nanowires are generally found to have vertical and non-polar side facets, while tilted and polar nanofacets were described for Au-assisted GaAs nanowires. We employ VLS nucleation theory to understand the effect of the droplet material on the lateral facets. Optoelectronic applications require long minority carrier lifetimes at room temperature. We fabricate GaAs/(Al,Ga)As core-shell nanowires and analyse them by transient photoluminescence (PL) spectroscopy. The results are 2.5 ns for the self-assisted nanowires as well as 9 ps for the Au-assisted nanowires. By temperature-dependent PL measurements we find a characteristic activation energy of 77 meV that is present only in the Au-assisted nanowires. We conclude that most likely Au is incorporated from the droplets into the GaAs nanowires and acts as a deep, non-radiative recombination centre.

  4. Scanning electron microscopy analysis of the growth of dental plaque on the surfaces of removable orthodontic aligners after the use of different cleaning methods

    Directory of Open Access Journals (Sweden)

    Levrini L

    2015-12-01

    Full Text Available Luca Levrini, Francesca Novara, Silvia Margherini, Camilla Tenconi, Mario Raspanti Department of Surgical and Morphological Sciences, Dental Hygiene School, Research Centre Cranio Facial Disease and Medicine, University of Insubria, Varese, Italy Background: Advances in orthodontics are leading to the use of minimally invasive technologies, such as transparent removable aligners, and are able to meet high demands in terms of performance and esthetics. However, the most correct method of cleaning these appliances, in order to minimize the effects of microbial colonization, remains to be determined. Purpose: The aim of the present study was to identify the most effective method of cleaning removable orthodontic aligners, analyzing the growth of dental plaque as observed under scanning electron microscopy. Methods: Twelve subjects were selected for the study. All were free from caries and periodontal disease and were candidates for orthodontic therapy with invisible orthodontic aligners. The trial had a duration of 6 weeks, divided into three 2-week stages, during which three sets of aligners were used. In each stage, the subjects were asked to use a different method of cleaning their aligners: 1 running water (control condition; 2 effervescent tablets containing sodium carbonate and sulfate crystals followed by brushing with a toothbrush; and 3 brushing alone (with a toothbrush and toothpaste. At the end of each 2-week stage, the surfaces of the aligners were analyzed under scanning electron microscopy. Results: The best results were obtained with brushing combined with the use of sodium carbonate and sulfate crystals; brushing alone gave slightly inferior results. Conclusion: On the basis of previous literature results relating to devices in resin, studies evaluating the reliability of domestic ultrasonic baths for domestic use should be encouraged. At present, pending the availability of experimental evidence, it can be suggested that dental

  5. Grain-boundary engineering applied to grain growth in a high temperature material

    International Nuclear Information System (INIS)

    Huda, Z.

    1993-01-01

    Crystallography of grain boundaries are determined for a high temperature material, before and after grain growth processes, so as to study the induction of special properties useful for application in components of a gas-turbine engine. The philosophy of grain-boundary engineering is applied to grain growth in APK-6, a powder formed nickel-base superalloy so as to establish the possible structure/property relationships. The alloy in the as received condition is shown to possess a strong texture and contained coincident site lattices (CSL) boundaries with most boundaries having sigma values in the range of 3 > sigma > 25. A normal grain-growth heat treatment result in a good population of low angle grain boundaries, and drastically reduces the proportion of CSL boundaries. A strong [011] annealing texture is observed after an intermediate grain growth; most grain boundaries, here, tend to be high angle indicating a possibility of possessing special properties. (author)

  6. Investigation of Growth and Survival of Transplanted Plane and Pine Trees According to IBA Application, Tree Age, Transplanting Time and Method

    Directory of Open Access Journals (Sweden)

    N. Etemadi

    2015-03-01

    Full Text Available The major problems in transplanting the landscape trees are high level of mortality and low establishment rate of transplanted trees, especially in the first year. In order to achieve the best condition for successful transplanting of pine and plane trees in Isfahan landscape, the present study was carried out based on a completely randomized block design with four replicates and three treatments including transplanting method (balled and burlapped and bare root, tree age (immature and mature and IBA application (0 and 150 mg/L. Trees were transplanted during 2009 and 2010 in three times (dormant season, early and late growing season. Survival rate and Relative Growth Rate index based on tree height (RGRH and trunk diameter (RGRD were measured during the first and second years. Trees transplanted early in the growing season showed the most survival percentage during the two years, as compared to other transplanting dates. Survival of Balled and burlapped and immature transplanted trees was significantly greater than bare root or mature trees. The significant effect of age treatment was continued in the second year. IBA treatment had no effect on survival rate of the studied species. Balled and burlapped and immature transplanted pine trees also had higher RGRH and RGRD compared to bare root or mature trees. According to the results of this study, early growing season is the best time for transplanting pine and plane trees. Also, transplanting of immature trees using balled and burlapped method is recommended to increase the survival and establishment rate.

  7. An assessment of the toxicity of crude oils in soils using earthworms, Microtox reg-sign Solid-Phase and early plant growth methods

    International Nuclear Information System (INIS)

    Vipond, T.E.; Dorn, P.B.; Salanitro, J.P.; Huesemann, M.H.; Wisniewski, H.L.; Moore, K.O.

    1993-01-01

    The qualitative assessment of soil quality resulting from a chemical or oil spill and/or remediation effort may be obtained by evaluating the toxicity to soil organisms. To enhance the authors understanding of the soil quality resulting from oil spill remediation, they have begun a program to assess three soil toxicity test methods. A heavy, medium and light crude oil were spiked into a sandy soil and a topsoil in the laboratory. The earthworm (Eisenia foetida) 14-d lethality assay, the modified Microbics Microtox Solid-Phase method, and the 14-d agricultural plant seed germination rate and plant growth assay were exposed to combinations of crude oils and soils. Earthworms were 1.4 to 14 times more sensitive than the Microtox and 1.3 to >77 times more sensitive than the plants to the oily soils. Light crude oil in sandy soil was the most toxic to the earthworms. Six percent heavy crude oil in topsoil showed little effect on the three organisms with LC50's ranging from 6.7--7.3 for earthworms to no effects on plants. These bioassay techniques are shown to be sensitive indicators of soil quality and may be used to evaluate the soil quality of remediated oil soils

  8. Assessment of the microbial growth potential of slow sand filtrate with the biomass production potential test in comparison with the assimilable organic carbon method.

    Science.gov (United States)

    van der Kooij, Dick; Veenendaal, Harm R; van der Mark, Ed J; Dignum, Marco

    2017-11-15

    Slow sand filtration is the final treatment step at four surface-water supplies in the Netherlands. The microbial growth potential (MGP) of the finished water was measured with the assimilable organic carbon (AOC) method using pure cultures and the biomass production potential (BPP) test. In the BPP test, water samples were incubated untreated at 25 °C and the active-biomass concentration was measured by adenosine tri-phosphate (ATP) analysis. Addition of a river-water inoculum improved the test performance and characteristic growth and maintenance profiles of the water were obtained. The maximum ATP concentration attained within seven days and the cumulative biomass production after 14 days of incubation (BPC 14 , d ng ATP L -1 ) showed highly significant and strong linear relationships with the AOC in the slow sand filtrates. The lowest AOC and BPC 14 levels were observed in the supplies applying dune filtration without ozonation in post treatment, with AOC/TOC = 1.7 ± 0.3 μg acetate-C equivalents mg -1 C and BPC 14 /TOC = 16.3 ± 2.2 d ng ATP mg -1 C, corresponding with 1.2 ± 0.19 ng ATP mg -1 C. These characteristics may represent the lowest specific MGP of natural organic matter achievable by biofiltration at temperatures ≤20 °C. The AOC and BPC 14 concentrations in the slow sand filtrate of the supply treating lake water by ozonation with granular-activated-carbon filtration and slow sand filtration as post treatment increased with decreasing temperature. The BPP test revealed that this slow sand filtrate sampled at 2 °C contained growth-promoting compounds that were not detected with the AOC test. These observations demonstrate the utility of the BPP test for assessing the MGP of drinking water and show the performance limits of biofiltration for MGP reduction. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Scanning electron microscopy analysis of the growth of dental plaque on the surfaces of removable orthodontic aligners after the use of different cleaning methods.

    Science.gov (United States)

    Levrini, Luca; Novara, Francesca; Margherini, Silvia; Tenconi, Camilla; Raspanti, Mario

    2015-01-01

    Advances in orthodontics are leading to the use of minimally invasive technologies, such as transparent removable aligners, and are able to meet high demands in terms of performance and esthetics. However, the most correct method of cleaning these appliances, in order to minimize the effects of microbial colonization, remains to be determined. The aim of the present study was to identify the most effective method of cleaning removable orthodontic aligners, analyzing the growth of dental plaque as observed under scanning electron microscopy. Twelve subjects were selected for the study. All were free from caries and periodontal disease and were candidates for orthodontic therapy with invisible orthodontic aligners. The trial had a duration of 6 weeks, divided into three 2-week stages, during which three sets of aligners were used. In each stage, the subjects were asked to use a different method of cleaning their aligners: 1) running water (control condition); 2) effervescent tablets containing sodium carbonate and sulfate crystals followed by brushing with a toothbrush; and 3) brushing alone (with a toothbrush and toothpaste). At the end of each 2-week stage, the surfaces of the aligners were analyzed under scanning electron microscopy. The best results were obtained with brushing combined with the use of sodium carbonate and sulfate crystals; brushing alone gave slightly inferior results. On the basis of previous literature results relating to devices in resin, studies evaluating the reliability of domestic ultrasonic baths for domestic use should be encouraged. At present, pending the availability of experimental evidence, it can be suggested that dental hygienists should strongly advise patients wearing orthodontic aligners to clean them using a combination of brushing and commercially available tablets for cleaning oral appliances.

  10. A novel method, digital genome scanning detects KRAS gene amplification in gastric cancers: involvement of overexpressed wild-type KRAS in downstream signaling and cancer cell growth

    Directory of Open Access Journals (Sweden)

    Yanagihara Kazuyoshi

    2009-06-01

    Full Text Available Abstract Background Gastric cancer is the third most common malignancy affecting the general population worldwide. Aberrant activation of KRAS is a key factor in the development of many types of tumor, however, oncogenic mutations of KRAS are infrequent in gastric cancer. We have developed a novel quantitative method of analysis of DNA copy number, termed digital genome scanning (DGS, which is based on the enumeration of short restriction fragments, and does not involve PCR or hybridization. In the current study, we used DGS to survey copy-number alterations in gastric cancer cells. Methods DGS of gastric cancer cell lines was performed using the sequences of 5000 to 15000 restriction fragments. We screened 20 gastric cancer cell lines and 86 primary gastric tumors for KRAS amplification by quantitative PCR, and investigated KRAS amplification at the DNA, mRNA and protein levels by mutational analysis, real-time PCR, immunoblot analysis, GTP-RAS pull-down assay and immunohistochemical analysis. The effect of KRAS knock-down on the activation of p44/42 MAP kinase and AKT and on cell growth were examined by immunoblot and colorimetric assay, respectively. Results DGS analysis of the HSC45 gastric cancer cell line revealed the amplification of a 500-kb region on chromosome 12p12.1, which contains the KRAS gene locus. Amplification of the KRAS locus was detected in 15% (3/20 of gastric cancer cell lines (8–18-fold amplification and 4.7% (4/86 of primary gastric tumors (8–50-fold amplification. KRAS mutations were identified in two of the three cell lines in which KRAS was amplified, but were not detected in any of the primary tumors. Overexpression of KRAS protein correlated directly with increased KRAS copy number. The level of GTP-bound KRAS was elevated following serum stimulation in cells with amplified wild-type KRAS, but not in cells with amplified mutant KRAS. Knock-down of KRAS in gastric cancer cells that carried amplified wild

  11. Single crystal growth of 67%BiFeO3-33%BaTiO3 solution by the floating zone method

    Science.gov (United States)

    Rong, Y.; Zheng, H.; Krogstad, M. J.; Mitchell, J. F.; Phelan, D.

    2018-01-01

    The growth conditions and the resultant grain morphologies and phase purities from floating-zone growth of 67%BiFeO3-33%BaTiO3 (BF-33BT) single crystals are reported. We find two formidable challenges for the growth. First, a low-melting point constituent leads to a pre-melt zone in the feed-rod that adversely affects growth stability. Second, constitutional super-cooling (CSC), which was found to lead to dendritic and columnar features in the grain morphology, necessitates slow traveling rates during growth. Both challenges were addressed by modifications to the floating-zone furnace that steepened the temperature gradient at the melt-solid interfaces. Slow growth was also required to counter the effects of CSC. Single crystals with typical dimensions of hundreds of microns have been obtained which possess high quality and are suitable for detailed structural studies.

  12. Single crystal growth of 67%BiFeO 3 -33%BaTiO 3 solution by the floating zone method

    Energy Technology Data Exchange (ETDEWEB)

    Rong, Y.; Zheng, H.; Krogstad, M. J.; Mitchell, J. F.; Phelan, D.

    2018-01-01

    The growth conditions and the resultant grain morphologies and phase purities from floating-zone growth of 67%BiFeO3-33%BaTiO3 (BF-33BT) single crystals are reported. We find two formidable challenges for the growth. First, a low-melting point constituent leads to a pre-melt zone in the feed-rod that adversely affects growth stability. Second, constitutional super-cooling (CSC), which was found to lead to dendritic and columnar features in the grain morphology, necessitates slow traveling rates during growth. Both challenges were addressed by modifications to the floating-zone furnace that steepened the temperature gradient at the melt-solid interfaces. Slow growth was also required to counter the effects of CSC. Single crystals with typical dimensions of hundreds of microns have been obtained which possess high quality and are suitable for detailed structural studies.

  13. Development of an Efficient Regeneration and Transformation Method for Nicothiana tabacum L. through the Optimization of Growth Regulators and Sucrose Concentration

    Directory of Open Access Journals (Sweden)

    maria Beihaghi

    2018-03-01

    Full Text Available Introduction: Plant tissue culture is a collection of techniques used to maintain or grow plant cells, tissues or organs under sterile conditions on a nutrient culture medium of known composition and widely used to produce clones of a plant in a method known as micropropagation. Plant research often involves growing new plants in a controlled environment. These may be plants that we have genetically altered in some way or may be plants of which we need many copies all exactly alike. These things can be accomplished through tissue culture of small tissue pieces from the plant of interest. These small pieces may come from a single mother plant or they may be the result of genetic transformation of single plant cells which are then encouraged to grow and to ultimately develop into a whole plant. Tissue culture techniques are often used for commercial production of plants as well as for plant research. Tobacco (Nicotiana tabacum L. is one of the most important model plants used in the physiologic, genetic and tissue culture studies. The manipulation of tobacco genetic structure requires an efficient technique of gene transferring and regeneration. Whereas, the tobacco plant is a very effective bioreactor in the production of recombinant proteins, in this research we optimized the best tissue culture system and also, genetic transformation process of this plant. Materials and Methods: Our plant tissue culture protocols, Include helpful information for Murashige and Skoog media, plant growth regulators, plant growth hormones, plant transformation systems, and other products for plant tissue culture. For this purpose, different concentrations of sucrose and 4 combinations of growth regulators (BAP and NAA on callus induction, direct shoot regeneration and rooting were examined in a factorial experiment based on completely randomized design with 3 replications. The sensitivity of tobacco explants to kanamycin was examined through the cultivation of them

  14. Growth of dopamine crystals

    Energy Technology Data Exchange (ETDEWEB)

    Patil, Vidya, E-mail: vidya.patil@ruparel.edu; Patki, Mugdha, E-mail: mugdha.patki@ruparel.edu [D. G. Ruparel College, Senapati Bapat Marg, Mahim, Mumbai – 400 016 (India)

    2016-05-06

    Many nonlinear optical (NLO) crystals have been identified as potential candidates in optical and electro-optical devices. Use of NLO organic crystals is expected in photonic applications. Hence organic nonlinear optical materials have been intensely investigated due to their potentially high nonlinearities, and rapid response in electro-optic effect compared to inorganic NLO materials. There are many methods to grow organic crystals such as vapor growth method, melt growth method and solution growth method. Out of these methods, solution growth method is useful in providing constraint free crystal. Single crystals of Dopamine have been grown by evaporating the solvents from aqueous solution. Crystals obtained were of the size of orders of mm. The crystal structure of dopamine was determined using XRD technique. Images of crystals were obtained using FEG SEM Quanta Series under high vacuum and low KV.

  15. Growth Disorders

    Science.gov (United States)

    ... too little of it may be very short. Treatment with growth hormone can stimulate growth. People can also have too much growth hormone. Usually the cause is a pituitary gland tumor, which is not cancer. Too much growth hormone can cause gigantism in children, where their bones and their body ...

  16. Assessment of the Factors Contributing to the Growth or Spoilage of Meyerozyma guilliermondii in Organic Yogurt: Comparison of Methods for Strain Differentiation

    Directory of Open Access Journals (Sweden)

    Petra Wrent

    2015-08-01

    Full Text Available In this work we analyze the spoiling potential of Meyerozyma guilliermondii in yogurt. The analysis was based on contaminated samples sent to us by an industrial laboratory over two years. All the plain and fruit yogurt packages were heavily contaminated by yeasts, but only the last ones, containing fermentable sugars besides lactose, were spoiled by gas swelling. These strains were unable to grow and ferment lactose (as the type strain; they did grow on lactate plus galactose, fermented glucose and sucrose, and galactose (weakly, but did not compete with lactic acid bacteria for lactose. This enables them to grow in any yogurt, although only those with added jam were spoiled due to the fermentation of the fruit sugars. Fermentation, but not growth, was strongly inhibited at 8 °C. In consequence, in plain yogurt as well as in any yogurt maintained at low temperature, yeast contamination would not be detected by the consumer. The risk could be enhanced because the species has been proposed for biological control of fungal infections in organic agriculture. The combination of the IGS PCR-RFLP (amplification of the intergenic spacer region of rDNA followed by restriction fragment length polymorphism analysis method and mitochondrial DNA-RFLP makes a good tool to trace and control the contamination by M. guilliermondii.

  17. Cd{sub 1−x}Mn{sub x}Te ultrasmall quantum dots growth in a silicate glass matrix by the fusion method

    Energy Technology Data Exchange (ETDEWEB)

    Dantas, Noelio Oliveira; Lima Fernandes, Guilherme de; Almeida Silva, Anielle Christine [Laboratório de Novos Materiais Isolantes e Semicondutores (LNMIS), Instituto de Física, Universidade Federal de Uberlândia, 38408-100 Uberlândia, MG (Brazil); Baffa, Oswaldo; Gómez, Jorge Antônio [Departamento de Física, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, 14040-901 Ribeirão Preto, SP (Brazil)

    2014-09-29

    In this study, we synthesized Cd{sub 1−x}Mn{sub x}Te ultrasmall quantum dots (USQDs) in SiO{sub 2}-Na{sub 2}CO{sub 3}-Al{sub 2}O{sub 3}-B{sub 2}O{sub 3} glass system using the fusion method. Growth of these Cd{sub 1−x}Mn{sub x}Te USQDs was confirmed by optical absorption, atomic force microscopy (AFM), magnetic force microscopy (MFM), scanning transmission electron microscopy (TEM), and electron paramagnetic resonance (EPR) measurements. The blueshift of absorption transition with increasing manganese concentration gives evidence of incorporation of manganese ions (Mn{sup 2+}) in CdTe USQDs. AFM, TEM, and MFM confirmed, respectively, the formation of high quality Cd{sub 1−x}Mn{sub x}Te USQDs with uniformly distributed size and magnetic phases. Furthermore, EPR spectra showed six lines associated to the S = 5/2 spin half-filled d-state, characteristic of Mn{sup 2+}, and confirmed that Mn{sup 2+} are located in the sites core and surface of the CdTe USQD. Therefore, synthesis of high quality Cd{sub 1−x}Mn{sub x}Te USQDs may allow the control of optical and magnetic properties.

  18. Significance of Herbaspirillum seropedicae inoculation and/or straw amendment on growth and dinitrogen fixation of wheat using 15N-dilution method.

    Science.gov (United States)

    el-Komy, H M; Saad, O A; Hetta, A M

    2003-01-01

    The effect of Herbaspirillum seropedicae inoculation and/or maize straw (0, 5 and 10 Mg/hm2) amendment on the growth and N2 fixation of wheat was determined in pot experiments using 15N-dilution method. Inoculation resulted in accumulation of fixed nitrogen, and % N from atmosphere being 24.6 and 26.5% in wheat shoot and grain, respectively. Straw amendment reduced % Natm to 16.1 and 20.2% at high straw level (10 Mg/hm2). Rational nitrogen fertilization (180 kg N/hm2) completely inhibited N2 fixation by H. seropedicae inoculation. Bacterial inoculation increased dry shoot and grain yield up to 23 and 31%, respectively. The highest levels of shoot and grain dry mass (46.5 and 42.4%) were obtained by N-fertilization in both inoculated and uninoculated plants. Total shoot and grain N-yield increased irrespective of organic matter amendment by inoculation up to 9 and 25%, respectively. N-fertilized plants recorded a maximum increase in N-yield (57 and 51%). H. seropedicae was reisolated from inoculated wheat histosphere after harvesting (90 d from sowing). Neither organic matter nor mineral nitrogen applications had any marked effect on bacterial total counts colonizing wheat histosphere. Moreover, no symptoms of mottled stripe disease were observed on leaves and stems of inoculated plants.

  19. The Effect of Alumina and Magnesia Supported Germanium Nanoparticles on the Growth of Carbon Nanotubes in the Chemical Vapor Deposition Method

    Directory of Open Access Journals (Sweden)

    Ghazaleh Allaedini

    2015-01-01

    Full Text Available The effect of alumina and magnesia supported germanium (Ge nanoparticles on the synthesis of carbon nanotubes (CNTs using the chemical vapor deposition (CVD method in atmospheric pressure was investigated. The TEM micrographs confirmed the formation of carbon nanotubes, and the field emission scanning electron microscopy (FESEM analysis suggested a tip-growth mechanism for the grown carbon nanotubes. The X-ray diffraction (XRD pattern indicated a graphitic nature of the carbon nanotubes. The obtained CNTs using Ge nanoparticles supported by MgO resulted in a higher degree of graphitization than the CNTs obtained using Ge nanoparticles supported by Al2O3. Raman spectroscopy analysis of the CNTs confirmed the presence of radial breathing modes (RBM, which verified the formation of CNTs. High frequency Raman analysis demonstrated that the degree of graphitization of the synthesized CNTs using magnesia supported Ge nanoparticles is higher than that of the alumina supported Ge nanoparticles with the values of (ID/IG ratios equal to 0.45 and 0.73, respectively.

  20. Concentration of the 241Pu in air samples from Chernobyl at Belgrade site estimated by a 241Am in growth method

    International Nuclear Information System (INIS)

    Vukanac, I.; Novkovic, D.; Djurasevic, M.; Obradovic, Z.; Kandi, A.

    2006-01-01

    The surface air samples collected in the first half of May 1986 at Vinca- Belgrade site were prepared and measured at the end of the 1991 and beginning of the 1992. year. Activity concentrations of the 137 Cs immediately after the Chernobyl accident were determined by means of gamma spectrometry, while the air activity concentration of 238 Pu and 239,240 Pu were determined by alpha spectrometry, after the plutonium radiochemical separation. The 236 Pu was used as a tracer. The same samples were remeasured after 13 years, during the 2004. The surface air activity concentrations of 241 Pu were estimated by a 241 Am in-growth method. The built up activities of 236 Pu progenies were determined from the recorded spectra and also calculated using the Bateman equations. The 241 Am activity in the remeasured samples, obtained by complex spectral analysis was confirmed by gamma spectrometry. The 241 Pu activity concentration in measured air samples ranged from 240 μBq/m3 to 7800 μBq/m3. The average activity concentration ratio 241 Pu/ 239,240 Pu originated from Chernobyl accident was approximately 100. (authors)