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Sample records for plate dilution method

  1. An Evaluation Method for the Suppression of Pathogenic Fusarium oxysporum by Soil Microorganisms Using the Dilution Plate Technique.

    Science.gov (United States)

    Mitsuboshi, Masahiro; Kioka, Yuuzou; Noguchi, Katsunori; Asakawa, Susumu

    2016-09-29

    Soil-borne diseases caused by pathogenic microorganisms are one of the main factors responsible for the decline in crop yields in farmlands. Pathogenic Fusarium oxysporum causes serious damage to various crops, and, thus, a feasible diagnostic method for soil-borne diseases is required. We herein examined a simple method to evaluate the suppressiveness of soil microorganisms against a pathogen by co-cultivating indigenous soil microorganisms and a pathogenic fungus (F. oxysporum f. sp. spinaciae). We inoculated F. oxysporum onto the center of agar medium plates mixed with a dilution series of a suspension of organic fertilizers or soil. After an approximately one-week cultivation, the growth degree of F. oxysporum was estimated based on the size of the colonies that formed on the plates. The growth degree of F. oxysporum significantly differed among the organic fertilizers tested, indicating the usefulness of the method for evaluating suppressiveness by organic fertilizers. Differences in the growth degrees of F. oxysporum were associated with the incidence of disease in spinach on soil treated with organic fertilizers and inoculated with a pathogenic F. oxysporum strain. These results suggested that this method provides some useful information on the suppressiveness of organic fertilizers and soil against Fusarium wilt.

  2. Optimization of single plate-serial dilution spotting (SP-SDS) with sample anchoring as an assured method for bacterial and yeast cfu enumeration and single colony isolation from diverse samples.

    Science.gov (United States)

    Thomas, Pious; Sekhar, Aparna C; Upreti, Reshmi; Mujawar, Mohammad M; Pasha, Sadiq S

    2015-12-01

    We propose a simple technique for bacterial and yeast cfu estimations from diverse samples with no prior idea of viable counts, designated as single plate-serial dilution spotting (SP-SDS) with the prime recommendation of sample anchoring (10(0) stocks). For pure cultures, serial dilutions were prepared from 0.1 OD (10(0)) stock and 20 μl aliquots of six dilutions (10(1)-10(6)) were applied as 10-15 micro-drops in six sectors over agar-gelled medium in 9-cm plates. For liquid samples 10(0)-10(5) dilutions, and for colloidal suspensions and solid samples (10% w/v), 10(1)-10(6) dilutions were used. Following incubation, at least one dilution level yielded 6-60 cfu per sector comparable to the standard method involving 100 μl samples. Tested on diverse bacteria, composite samples and Saccharomyces cerevisiae, SP-SDS offered wider applicability over alternative methods like drop-plating and track-dilution for cfu estimation, single colony isolation and culture purity testing, particularly suiting low resource settings.

  3. Optimization of single plate-serial dilution spotting (SP-SDS with sample anchoring as an assured method for bacterial and yeast cfu enumeration and single colony isolation from diverse samples

    Directory of Open Access Journals (Sweden)

    Pious Thomas

    2015-12-01

    Full Text Available We propose a simple technique for bacterial and yeast cfu estimations from diverse samples with no prior idea of viable counts, designated as single plate-serial dilution spotting (SP-SDS with the prime recommendation of sample anchoring (100 stocks. For pure cultures, serial dilutions were prepared from 0.1 OD (100 stock and 20 μl aliquots of six dilutions (101–106 were applied as 10–15 micro-drops in six sectors over agar-gelled medium in 9-cm plates. For liquid samples 100–105 dilutions, and for colloidal suspensions and solid samples (10% w/v, 101–106 dilutions were used. Following incubation, at least one dilution level yielded 6–60 cfu per sector comparable to the standard method involving 100 μl samples. Tested on diverse bacteria, composite samples and Saccharomyces cerevisiae, SP-SDS offered wider applicability over alternative methods like drop-plating and track-dilution for cfu estimation, single colony isolation and culture purity testing, particularly suiting low resource settings.

  4. Comparative study of some factors affecting enumeration of moulds using dilution plate techniques.

    Science.gov (United States)

    Bragulat, M R; Abarca, M L; Bruguera, M T; Cabañes, F J

    1992-11-01

    The influence of dilution plating technique, nature of diluent, culture media and incubation period on the enumeration of moulds have been studied. Three new culture media containing Auramine, Gentian Violet and Malachite Green respectively have been induced in this study. No significant differences were observed between results obtained after 3, 5 and 7 days of incubation. Significantly higher recoveries were obtained using the surface-spread method than pour plate method. Using the first technique no effect of diluent was observed, and among the different culture media studied higher counts were obtained with medium containing Auramine.

  5. Authentic Active Learning Activities Demonstrating the Use of Serial Dilutions and Plate Counts

    Directory of Open Access Journals (Sweden)

    Jordon K. March

    2011-09-01

    Full Text Available Serial dilution and plate counting is often taught in courses for both microbiology and allied health students. Lecture examples and examination questions addressing how the method is used can sometimes be contrived: artificial data sets may have little or no meaning other than to have students perform a calculation. Here we provide a set of activities employing data sets acquired from the primary literature. Our objective was to have the students think critically about a real scenario in which serial dilution and plate count was used. Each activity requires students to read a paragraph describing the study, predict the results, perform the appropriate calculations, and then evaluate the results in light of their predictions. To test the efficacy of these activities, a pretest quiz was given to approximately 100 students in an allied health/general microbiology course. After a lecture on how microbes are enumerated, students were given a different quiz. The class was then divided randomly into groups of three or four students and assigned one of the activities. A postactivity quiz was also administered. Approximately two weeks later, a serial dilution/plate count question was used on an examination and served as a final posttest. Standardized learning gains were calculated for the quiz administered after each learning activity. Even though learning gains were significantly higher after the lecture, there was also a significant improvement between the lecture and the activity. Using an exercise based on an authentic set of data significantly improved student learning gains, and is a useful practice for teaching microbiology.

  6. How to optimize the drop plate method for enumerating bacteria.

    Science.gov (United States)

    Herigstad, B; Hamilton, M; Heersink, J

    2001-03-01

    The drop plate (DP) method can be used to determine the number of viable suspended bacteria in a known beaker volume. The drop plate method has some advantages over the spread plate (SP) method. Less time and effort are required to dispense the drops onto an agar plate than to spread an equivalent total sample volume into the agar. By distributing the sample in drops, colony counting can be done faster and perhaps more accurately. Even though it has been present in the laboratory for many years, the drop plate method has not been standardized. Some technicians use 10-fold dilutions, others use twofold. Some technicians plate a total volume of 0.1 ml, others plate 0.2 ml. The optimal combination of such factors would be useful to know when performing the drop plate method. This investigation was conducted to determine (i) the standard deviation of the bacterial density estimate, (ii) the cost of performing the drop plate procedure, (iii) the optimal drop plate design, and (iv) the advantages of the drop plate method in comparison to the standard spread plate method. The optimal design is the combination of factor settings that achieves the smallest standard deviation for a fixed cost. Computer simulation techniques and regression analysis were used to express the standard deviation as a function of the beaker volume, dilution factor, and volume plated. The standard deviation expression is also applicable to the spread plate method.

  7. DILUTE SURFACTANT METHODS FOR CARBONATE FORMATIONS

    Energy Technology Data Exchange (ETDEWEB)

    Kishore K. Mohanty

    2005-01-01

    There are many carbonate reservoirs in US (and the world) with light oil and fracture pressure below its minimum miscibility pressure (or reservoir may be naturally fractured). Many carbonate reservoirs are naturally fractured. Waterflooding is effective in fractured reservoirs, if the formation is water-wet. Many fractured carbonate reservoirs, however, are mixed-wet and recoveries with conventional methods are low (less than 10%). Thermal and miscible tertiary recovery techniques are not effective in these reservoirs. Surfactant flooding (or huff-n-puff) is the only hope, yet it was developed for sandstone reservoirs in the past. The goal of this research is to evaluate dilute (hence relatively inexpensive) surfactant methods for carbonate formations and identify conditions under which they can be effective. Imbibition in an originally oil-wet 2D capillary is the fastest in the case of Alf-38 and slowest in the case of DTAB (among the surfactants studied). Force of adhesion studies and contact angle measurements show that greater wettability alteration is possible with these anionic surfactants than the cationic surfactant studied. The water imbibition rate does not increase monotonically with an increase in the surfactant concentration. A numerical model has been developed that fits the rate of imbibition. Plans for the next quarter include conducting simulation and imbibition studies.

  8. Dilute Surfactant Methods for Carbonate Formations

    Energy Technology Data Exchange (ETDEWEB)

    Kishore K. Mohanty

    2006-02-01

    There are many fractured carbonate reservoirs in US (and the world) with light oil. Waterflooding is effective in fractured reservoirs, if the formation is water-wet. Many fractured carbonate reservoirs, however, are mixed-wet and recoveries with conventional methods are low (less than 10%). The process of using dilute anionic surfactants in alkaline solutions has been investigated in this work for oil recovery from fractured oil-wet carbonate reservoirs both experimentally and numerically. This process is a surfactant-aided gravity drainage where surfactant diffuses into the matrix, lowers IFT and contact angle, which decrease capillary pressure and increase oil relative permeability enabling gravity to drain the oil up. Anionic surfactants have been identified which at dilute concentration of 0.05 wt% and optimal salinity can lower the interfacial tension and change the wettability of the calcite surface to intermediate/water-wet condition as well or better than the cationic surfactant DTAB with a West Texas crude oil. The force of adhesion in AFM of oil-wet regions changes after anionic surfactant treatment to values similar to those of water-wet regions. The AFM topography images showed that the oil-wetting material was removed from the surface by the anionic surfactant treatment. Adsorption studies indicate that the extent of adsorption for anionic surfactants on calcite minerals decreases with increase in pH and with decrease in salinity. Surfactant adsorption can be minimized in the presence of Na{sub 2}CO{sub 3}. Laboratory-scale surfactant brine imbibition experiments give high oil recovery (20-42% OOIP in 50 days; up to 60% in 200 days) for initially oil-wet cores through wettability alteration and IFT reduction. Small (<10%) initial gas saturation does not affect significantly the rate of oil recovery in the imbibition process, but larger gas saturation decreases the oil recovery rate. As the core permeability decreases, the rate of oil recovery reduces

  9. Mathematical methods for elastic plates

    CERN Document Server

    Constanda, Christian

    2014-01-01

    Mathematical models of deformation of elastic plates are used by applied mathematicians and engineers in connection with a wide range of practical applications, from microchip production to the construction of skyscrapers and aircraft. This book employs two important analytic techniques to solve the fundamental boundary value problems for the theory of plates with transverse shear deformation, which offers a more complete picture of the physical process of bending than Kirchhoff’s classical one.   The first method transfers the ellipticity of the governing system to the boundary, leading to singular integral equations on the contour of the domain. These equations, established on the basis of the properties of suitable layer potentials, are then solved in spaces of smooth (Hölder continuous and Hölder continuously differentiable) functions.   The second technique rewrites the differential system in terms of complex variables and fully integrates it, expressing the solution as a combination of complex ana...

  10. Simplified Method for Groundwater Treatment Using Dilution and Ceramic Filter

    Science.gov (United States)

    Musa, S.; Ariff, N. A.; Kadir, M. N. Abdul; Denan, F.

    2016-07-01

    Groundwater is one of the natural resources that is not susceptible to pollutants. However, increasing activities of municipal, industrial, agricultural or extreme land use activities have resulted in groundwater contamination as occured at the Research Centre for Soft Soil Malaysia (RECESS), Universiti Tun Hussein Onn Malaysia (UTHM). Thus, aims of this study is to treat groundwater by using rainwater and simple ceramic filter as a treatment agent. The treatment uses rain water dilution, ceramic filters and combined method of dilute and filtering as an alternate treatment which are simple and more practical compared to modern or chemical methods. The water went through dilution treatment processes able to get rid of 57% reduction compared to initial condition. Meanwhile, the water that passes through the filtering process successfully get rid of as much as 86% groundwater parameters where only chloride does not pass the standard. Favorable results for the combination methods of dilution and filtration methods that can succesfully eliminate 100% parameters that donot pass the standards of the Ministry of Health and the Interim National Drinking Water Quality Standard such as those found in groundwater in RECESS, UTHM especially sulfate and chloride. As a result, it allows the raw water that will use clean drinking water and safe. It also proves that the method used in this study is very effective in improving the quality of groundwater.

  11. Multiregional evaluation of the SimPlate heterotrophic plate count method compared to the standard plate count agar pour plate method in water.

    Science.gov (United States)

    Jackson, R W; Osborne, K; Barnes, G; Jolliff, C; Zamani, D; Roll, B; Stillings, A; Herzog, D; Cannon, S; Loveland, S

    2000-01-01

    A new SimPlate heterotrophic plate count (HPC) method (IDEXX Laboratories, Westbrook, Maine) was compared with the pour plate method at 35 degrees C for 48 h. Six laboratories tested a total of 632 water samples. The SimPlate HPC method was found to be equivalent to the pour plate method by regression analysis (r = 0. 95; y = 0.99X + 0.06).

  12. Multiregional Evaluation of the SimPlate Heterotrophic Plate Count Method Compared to the Standard Plate Count Agar Pour Plate Method in Water

    OpenAIRE

    Jackson, R. Wayne; Osborne, Karen; Barnes, Gary; Jolliff, Carol; Zamani, Dianna; Roll, Bruce; Stillings, Amy; Herzog, David; Cannon, Shelly; Loveland, Scott

    2000-01-01

    A new SimPlate heterotrophic plate count (HPC) method (IDEXX Laboratories, Westbrook, Maine) was compared with the pour plate method at 35°C for 48 h. Six laboratories tested a total of 632 water samples. The SimPlate HPC method was found to be equivalent to the pour plate method by regression analysis (r = 0.95; y = 0.99X + 0.06).

  13. A lattice Boltzmann method for dilute polymer solutions.

    Science.gov (United States)

    Singh, Shiwani; Subramanian, Ganesh; Ansumali, Santosh

    2011-06-13

    We present a lattice Boltzmann approach for the simulation of non-Newtonian fluids. The method is illustrated for the specific case of dilute polymer solutions. With the appropriate local equilibrium distribution, phase-space dynamics on a lattice, driven by a Bhatnagar-Gross-Krook (BGK) relaxation term, leads to a solution of the Fokker-Planck equation governing the probability density of polymer configurations. Results for the bulk rheological characteristics for steady and start-up shear flow are presented, and compare favourably with those obtained using Brownian dynamics simulations. The new method is less expensive than stochastic simulation techniques, particularly in the range of small to moderate Weissenberg numbers (Wi).

  14. Effusion plate using additive manufacturing methods

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Thomas Edward; Keener, Christopher Paul; Ostebee, Heath Michael; Wegerif, Daniel Gerritt

    2016-04-12

    Additive manufacturing techniques may be utilized to construct effusion plates. Such additive manufacturing techniques may include defining a configuration for an effusion plate having one or more internal cooling channels. The manufacturing techniques may further include depositing a powder into a chamber, applying an energy source to the deposited powder, and consolidating the powder into a cross-sectional shape corresponding to the defined configuration. Such methods may be implemented to construct an effusion plate having one or more channels with a curved cross-sectional geometry.

  15. Effusion plate using additive manufacturing methods

    Science.gov (United States)

    Johnson, Thomas Edward; Keener, Christopher Paul; Ostebee, Heath Michael; Wegerif, Daniel Gerritt

    2016-04-12

    Additive manufacturing techniques may be utilized to construct effusion plates. Such additive manufacturing techniques may include defining a configuration for an effusion plate having one or more internal cooling channels. The manufacturing techniques may further include depositing a powder into a chamber, applying an energy source to the deposited powder, and consolidating the powder into a cross-sectional shape corresponding to the defined configuration. Such methods may be implemented to construct an effusion plate having one or more channels with a curved cross-sectional geometry.

  16. Agar dilution method for susceptibility testing of Neisseria gonorrhoeae

    Directory of Open Access Journals (Sweden)

    Marta C de Castillo

    1996-12-01

    Full Text Available The antibiotic susceptibilities of Neisseria gonorrhoeae isolates obtained from patients attending a clinic for sexually transmitted diseases in Tucumán, Argentina, were determined by the agar dilution method (MIC. 3.5% of the isolates produced ²-lactamase. A total of 96.5% of ²-lactamase negative isolates tested were susceptible to penicillin (MIC < 2 µgml-1; 14.03% of the tested isolates were resistant to tetracycline (MIC < 2 µgml-1, and 98% of the tested isolates were susceptible to spectinomycin (MIC < 64 µgml-1. The MICs for 95% of the isolates, tested for other drugs were: < 2 µgml-1 for cefoxitin, < 0.06 µgml-1 for cefotaxime, < 0.25 µgml-1 for norfloxacin, < 10 µgml-1 for cephaloridine, < 10 µgml-1 for cephalexin, and < 50 µgml-1 for kanamycin. Antibiotic resistance among N. gonorrhoeae isolates from Tucumán, Argentina, appeared to be primarily limited to penicillin and tetracycline, which has been a general use against gonorrhoeae in Tucumán since 1960. Periodic monitoring of the underlying susceptibility profiles of the N. gonorrhoeae strains prevalent in areas of frequent transmission may provide clues regarding treatment options and emerging of drug resistance.

  17. In vitro effect of intracanal medicaments on strict anaerobes by means of the broth dilution method

    Directory of Open Access Journals (Sweden)

    ROSA Odila Pereira da Silva

    2002-01-01

    Full Text Available The determination of bacterial susceptibility to intracanal medicaments is a necessity. Nevertheless, few studies utilize the proper methodology to carry out that evaluation with anaerobes. In this study, the steps of a broth dilution method, carried out in microplates (microdilution and tubes (macrodilution, to test the effect of traditional intracanal medicaments on anaerobic bacteria are described. The results are presented as values of minimal inhibitory and bactericidal concentrations (MIC and MBC. Standardized inocula of the anaerobic bacteria Prevotella nigrescens (ATCC 33563, Fusobacterium nucleatum (ATCC 25586 and Clostridium perfringens (ATCC 13124, in reinforced Clostridium medium (RCM and supplemented Brucella broth, were submitted to different concentrations of calcium hydroxide, chlorhexidine digluconate, camphorated paramonochlorophenol and formocresol solutions. The drugs were diluted in the same culture broths, in microplates and tubes, and were then incubated in anaerobiosis jars at 37ºC for 48 or 96 hours. The determination of MICs was carried out through visual and spectrophotometric readings, and the determination of MBCs, through the plating of aliquots on RCM-blood agar. For that kind of study, the macromethod with spectrophotometric reading should be the natural choice. MICs and MBCs obtained with the macromethod were compatible with the known clinical performance of the studied medications, and the values varied according to the bacteria and culture media employed. RCM was the most effective medium and C. perfringens, the most resistant microorganism.

  18. Quantifying Methane Fluxes Simply and Accurately: The Tracer Dilution Method

    Science.gov (United States)

    Rella, Christopher; Crosson, Eric; Green, Roger; Hater, Gary; Dayton, Dave; Lafleur, Rick; Merrill, Ray; Tan, Sze; Thoma, Eben

    2010-05-01

    Methane is an important atmospheric constituent with a wide variety of sources, both natural and anthropogenic, including wetlands and other water bodies, permafrost, farms, landfills, and areas with significant petrochemical exploration, drilling, transport, or processing, or refining occurs. Despite its importance to the carbon cycle, its significant impact as a greenhouse gas, and its ubiquity in modern life as a source of energy, its sources and sinks in marine and terrestrial ecosystems are only poorly understood. This is largely because high quality, quantitative measurements of methane fluxes in these different environments have not been available, due both to the lack of robust field-deployable instrumentation as well as to the fact that most significant sources of methane extend over large areas (from 10's to 1,000,000's of square meters) and are heterogeneous emitters - i.e., the methane is not emitted evenly over the area in question. Quantifying the total methane emissions from such sources becomes a tremendous challenge, compounded by the fact that atmospheric transport from emission point to detection point can be highly variable. In this presentation we describe a robust, accurate, and easy-to-deploy technique called the tracer dilution method, in which a known gas (such as acetylene, nitrous oxide, or sulfur hexafluoride) is released in the same vicinity of the methane emissions. Measurements of methane and the tracer gas are then made downwind of the release point, in the so-called far-field, where the area of methane emissions cannot be distinguished from a point source (i.e., the two gas plumes are well-mixed). In this regime, the methane emissions are given by the ratio of the two measured concentrations, multiplied by the known tracer emission rate. The challenges associated with atmospheric variability and heterogeneous methane emissions are handled automatically by the transport and dispersion of the tracer. We present detailed methane flux

  19. Microporous microchannel plates and method of manufacturing same

    Energy Technology Data Exchange (ETDEWEB)

    Beetz, C.P. Jr.; Boerstler, R.W.; Steinbeck, J.; Winn, D.R.

    2000-04-04

    A microchannel plate and method of manufacturing same is provided. The microchannel plate includes a plate consisting of an anodized material and a plurality of channels which are formed during the anodization of the material and extend between the two sides of the plate. Electrodes are also disposed on each side of the plate for generating an electrical field within the channels. Preferably, the material is alumina and the channels are activated such that the channel walls are conductive and highly secondary emissive.

  20. Microporous microchannel plates and method of manufacturing same

    Energy Technology Data Exchange (ETDEWEB)

    Beetz, Jr., Charles P. (New Milford, CT); Boerstler, Robert W. (Woodbury, CT); Steinbeck, John (Fitzwilliam, NH); Winn, David R. (Wilton, CT)

    2000-01-01

    A microchannel plate and method of manufacturing same is provided. The microchannel plate includes a plate consisting of an anodized material and a plurality of channels which are formed during the anodization of the material and extend between the two sides of the plate. Electrodes are also disposed on each side of the plate for generating an electrical field within the channels. Preferably, the material is alumina and the channels are activated such that the channel walls are conductive and highly secondary emissive.

  1. Microporous microchannel plates and method of manufacturing same

    Science.gov (United States)

    Beetz, Jr., Charles P.; Boerstler, Robert W.; Steinbeck, John; Winn, David R.

    2000-01-01

    A microchannel plate and method of manufacturing same is provided. The microchannel plate includes a plate consisting of an anodized material and a plurality of channels which are formed during the anodization of the material and extend between the two sides of the plate. Electrodes are also disposed on each side of the plate for generating an electrical field within the channels. Preferably, the material is alumina and the channels are activated such that the channel walls are conductive and highly secondary emissive.

  2. Collaborative study comparing the spiral plate and aerobic plate count methods.

    Science.gov (United States)

    Gilchrist, J E; Donnelly, C B; Peeler, J T; Campbell, J E

    1977-07-01

    The spiral plate count method is a semiautomated plating technique that greatly reduces manpower and material costs normally associated with the pour plating technique. In this collaborative study, 8 laboratories compared the spiral and pour plating techniques, using 4 samples each of 3 products: frozen pumpkin pie, frozen chicken pot pie, and shampoo. The results show that 10 of the 12 comparisons of means of the pour and spiral methods were not significantly different; 2 values were significant at alpha = 0.01. Overall, the components of variance were less than that of the current milk standard, and the replicate per cent coefficient of variation was satisfactory. This study indicates that the spiral plate method is an acceptable alternative to the pour plate method; the spiral plate method has been adopted as official first action.

  3. Application of Shape Lock-on Method in Plate Rolling

    Institute of Scientific and Technical Information of China (English)

    HU Xian-lei; WANG Jun; WANG Zhao-dong; LIU Xiang-hua; WANG Guo-dong

    2004-01-01

    AGC system can improve the plate gauge precision, and damage the plate shape if the shape control loop is left quite open. This damage will cause wave during rolling wide-thin plate. A control strategy named shape lock-on method is afforded for plate shape control. This method requires APC instead of AGC at last one or two passes during rolling wide-thin plate. Approved by theory and on-line application, this method is good for the plate shape and crown control with small effect on gauge control.

  4. Strain resolving method of composite plane plates

    Directory of Open Access Journals (Sweden)

    Ion FUIOREA

    2011-06-01

    Full Text Available The paper deals with the extension of isotropic plates problem to the case of composite plates. In order to perform it, the Kirchhoff-Love hypotheses were “softened” by some additional ones. Considering the constitutive laws for composite materials the stress functions were eliminated by using Cauchy equations. As a result a partial derivative equation in displacements was obtained. Finally the boundary condition formulation was extended for the case of complex composite plates.

  5. Methods for identifying lipoxygenase producing microorganisms on agar plates

    NARCIS (Netherlands)

    Nyyssola, A.; Heshof, R.; Haarmann, T.; Eidner, J.; Westerholm-Parvinen, A.; Langfelder, K.; Kruus, K.; Graaff, de L.H.; Buchert, J.

    2012-01-01

    Plate assays for lipoxygenase producing microorganisms on agar plates have been developed. Both potassium iodide-starch and indamine dye formation methods were effective for detecting soybean lipoxygenase activity on agar plates. A positive result was also achieved using the beta-carotene bleaching

  6. Numerical results for extended field method applications. [thin plates

    Science.gov (United States)

    Donaldson, B. K.; Chander, S.

    1973-01-01

    This paper presents the numerical results obtained when a new method of analysis, called the extended field method, was applied to several thin plate problems including one with non-rectangular geometry, and one problem involving both beams and a plate. The numerical results show that the quality of the single plate solutions was satisfactory for all cases except those involving a freely deflecting plate corner. The results for the beam and plate structure were satisfactory even though the structure had a freely deflecting corner.

  7. A plating method for metal coating of fiber Bragg grating

    Institute of Scientific and Technical Information of China (English)

    Yulong Li; Hua Zhang; Yan Feng; Gang Peng

    2009-01-01

    We present a method for metal coating optical fiber and in-fiber Bragg grating. The technology process which is based on electroless plating and electroplating method is described in detail. The fiber is firstly coated with a thin copper or nickel plate with electroless plating method. Then, a thicker nickel plate is coated on the surface of the conductive layer. Under the optimum conditions, the surfaces of chemical plating and electroplating coatings are all smooth and compact. There is no visible defect found in the cross-section. Using this two-step metallization method, the in-fiber Bragg grating can be well protected and its thermal sensitivity can be enhanced. After the metallization process, the fiber sensor is successfully embedded in the 42CrMo steel by brazing method. Thus a smart metal structure is achieved. The embedding results show that the plating method for metallization protection of in-fiber Bragg grating is effective.

  8. Assessment of effective parameters on dilution using approximate reasoning methods in longwall mining method, Iran coal mines

    CERN Document Server

    Owladeghaffari, H; Saeedi, G H R

    2008-01-01

    Approximately more than 90% of all coal production in Iranian underground mines is derived directly longwall mining method. Out of seam dilution is one of the essential problems in these mines. Therefore the dilution can impose the additional cost of mining and milling. As a result, recognition of the effective parameters on the dilution has a remarkable role in industry. In this way, this paper has analyzed the influence of 13 parameters (attributed variables) versus the decision attribute (dilution value), so that using two approximate reasoning methods, namely Rough Set Theory (RST) and Self Organizing Neuro- Fuzzy Inference System (SONFIS) the best rules on our collected data sets has been extracted. The other benefit of later methods is to predict new unknown cases. So, the reduced sets (reducts) by RST have been obtained. Therefore the emerged results by utilizing mentioned methods shows that the high sensitive variables are thickness of layer, length of stope, rate of advance, number of miners, type of...

  9. Solution of non-rectangular plates with macroelement method

    Science.gov (United States)

    Delyavskyy, Mykhaylo; Rosinski, Krystian

    2017-03-01

    New approach to static analysis of thin non-rectangular arbitrarily loaded plates, called the macroelement method, has been developed in this paper. Macroelement is a rectangular plate which entirely contains real plate. The mathematical model of macroelement was built. The equilibrium equations are performed for macroelement and boundary conditions are written on the line corresponding to contour of real plate in the nodes which are zero points of trigonometric functions, included in the macroelement model. The load is applied only to separate nodes on the surface of real plate, whereas the complement of a plate to macroelement is unloaded. Analysis of construction is reduced to solving a system of linear algebraic equations. The method provides better accuracy compared to finite element method and requires less equations. There is trapeze plate clamped at inclined edge and simply supported at opposite one considered in this paper. The other edges of the plate are free. Uniformly distributed load on the surface of real plate is taken into account.

  10. Differences in vancomycin MIC among MRSA isolates by agar dilution and E test method

    Directory of Open Access Journals (Sweden)

    K Tandel

    2012-01-01

    Full Text Available In this study, the correlation between vancomycin minimum inhibitory concentration (MIC obtained by the E test technique and the Clinical And Laboratory Standards Institute (CLSI agar dilution method was evaluated. A total of 53 Methicillin Resistant Staphylococcus aureus (MRSA strains were tested by both the methods in the present study. MICs of vancomycin obtained by the E test method were consistently higher (+0.5 to 2 log2 dilutions than those obtained by the agar dilution method. Out of 53 MRSA isolates, 49 isolates showed higher MIC results by E test than by agar dilution method. Three isolates showed same MIC result by both methods. Since many studies have demonstrated increased clinical failure with MRSA isolates for which vancomycin MICs are increased (>1 μg/ml but still within the susceptibility range (≤ 2 μg/ml, our findings suggest the requirement to re-look into the breakpoints for vancomycin for determining sensitivity of MRSA isolates. Guidelines should also specify the method to be used for determining the MIC.

  11. Total N difference method and 15N isotope dilution methode - A comparative study on N-fixation

    OpenAIRE

    2002-01-01

    In the study, the 15N fixation of a number of green manure crops were studied using either the 15N dilution technique, or the simple total N difference method. The results of the two methods were not very different, and the total N difference method seemed to give as good results as the more complicated and expencive 15N dillution method.

  12. In vitro Comparison of Disk Diffusion and Agar Dilution Antibiotic Susceptibility Test Methods for Neisseria gonorrhoeae

    Directory of Open Access Journals (Sweden)

    Marta C de Castillo

    1998-07-01

    Full Text Available At present, most Neisseria gonorrhoeae testing is done with ß-lactamase and agar dilution tests with common therapeutic agents. Generally, in bacteriological diagnosis laboratories in Argentina, study of antibiotic susceptibility of N.gonorrhoeae is based on ß-lactamase determination and agar dilution method with common therapeutic agents. The National Committee for Clinical Laboratory Standards (NCCLS has recently described a disk diffusion test that produces results comparable to the reference agar dilution method for antibiotic susceptibility of N.gonorrhoeae, using a dispersion diagram for analyzing the correlation between both techniques. We obtained 57 gonococcal isolates from patients attending a clinic for sexually transmitted diseases in Tucumán, Argentina. Antibiotic susceptibility tests using agar dilution and disk diffusion techniques were compared. The established NCCLS interpretive criteria for both susceptibility methods appeared to be applicable to domestic gonococcal strains. The correlation between the MIC's and the zones of inhibition was studied for penicillin, ampicillin, cefoxitin, spectinomycin, cefotaxime, cephaloridine, cephalexin, tetracycline, norfloxacin and kanamycin. Dispersion diagrams showed a high correlation between both methods.

  13. Body composition among Sri Lankan infants by 18*O dilution method and the validity of anthropometric equations to predict body fat against 18*O dilution

    Science.gov (United States)

    Body composition indicators provide a better guidance for growth and nutritional status of the infants. This study was designed to (1) measure the body composition of the Sri Lankan infants using a reference method, the 18*O dilution method; (2) calculate the body fat content of the infants using pu...

  14. Evaluation of CLSI agar dilution method and Trek Sensititre broth microdilution panel for determining antimicrobial susceptibility of Streptococcus pneumoniae.

    Science.gov (United States)

    Zhang, Sean X; Rawte, Prasad; Brown, Shirley; Lo, Steven; Siebert, Heather; Pong-Porter, Sylvia; Low, Donald E; Jamieson, Frances B

    2011-02-01

    Both the CLSI agar dilution method and Trek Sensititre broth microdilution panel for Streptococcus pneumoniae antimicrobial susceptibility testing were evaluated against the reference CLSI broth microdilution method using the most recently published CLSI breakpoints. While agar dilution was not an optimal method, the commercial panel appeared to be an acceptable method, with minor errors encountered for ceftriaxone, penicillin, and meropenem.

  15. Evaluation of CLSI Agar Dilution Method and Trek Sensititre Broth Microdilution Panel for Determining Antimicrobial Susceptibility of Streptococcus pneumoniae▿

    Science.gov (United States)

    Zhang, Sean X.; Rawte, Prasad; Brown, Shirley; Lo, Steven; Siebert, Heather; Pong-Porter, Sylvia; Low, Donald E.; Jamieson, Frances B.

    2011-01-01

    Both the CLSI agar dilution method and Trek Sensititre broth microdilution panel for Streptococcus pneumoniae antimicrobial susceptibility testing were evaluated against the reference CLSI broth microdilution method using the most recently published CLSI breakpoints. While agar dilution was not an optimal method, the commercial panel appeared to be an acceptable method, with minor errors encountered for ceftriaxone, penicillin, and meropenem. PMID:21123533

  16. Vibration Analysis of Plates by MLS-Element Method

    Science.gov (United States)

    Zhou, L.; Xiang, Y.

    2010-05-01

    This paper presents a novel numerical method, the moving least square element (MLS-element) method for the free vibration analysis of plates based on the Mindlin shear deformable plate theory. In the MLS-element method, a plate can be first divided into multiple elements which are connected through selected nodal points on the interfaces of the elements. An element can be of any shape and the size of the element varies dependent on the problem at hand. The shape functions of the element for the transverse displacement and the rotations are derived based on the MLS interpolation technique. The convergence and accuracy of the method can be controlled by either increasing the number of elements or by increasing the number of MLS interpolation points within elements. Two selected examples for vibration of a simply supported square Mindlin plate and a clamped L-shaped Mindlin plate are studied to illustrate the versatility and accuracy of the proposed method. It shows that the proposed method is highly accurate and flexible for the vibration analysis of plate problems. The method can be further developed to bridge the existing meshless method and the powerful finite element method in dealing with various engineering computational problems, such as large deformation and crack propagation in solid mechanics.

  17. FRACTURE CALCULATION OF BENDING PLATES BY BOUNDARY COLLOCATION METHOD

    Institute of Scientific and Technical Information of China (English)

    王元汉; 伍佑伦; 余飞

    2003-01-01

    Fracture of Kirchhoff plates is analyzed by the theory of complex variables and boundary collocation method. The deflections, moments and shearing forces of the plates are assumed to be the functions of complex variables. The functions can satisfy a series of basic equations and governing conditions, such as the equilibrium equations in the domain, the boundary conditions on the crack surfaces and stress singularity at the crack tips. Thus, it ts only necessary to consider the boundary conditions on the external boundaries of the plate, which can be approximately satisfied by the collocation method and least square technique. Different boundary conditions and loading cases of the cracked plates are analyzed and calculated. Compared to other methods, the numerical examples show that the present method has many advantages such as good accuracy and less computer time This is an effective semi-analytical and semi-numerical method.

  18. A spectroscopic method for determining thickness of quartz wave plate

    Institute of Scientific and Technical Information of China (English)

    Weiwei Feng; Lihuang Lin; Ligang Chen; Huafeng Zhu; Ruxin Li; Zhizhan Xu

    2006-01-01

    A spectroscopic method to determine thickness of quartz wave plate is presented. The method is based on chromatic polarization interferometry. With the polarization-resolved transmission spectrum (PRTS)curve, the phase retardation of quartz wave plate can be determined at a wide spectral range from 200 to2000 nm obviously. Through accurate judgment of extreme points of PRTS curve at long-wave band, the physical thickness of quartz wave plates can be obtained exactly. We give a measuring example and the error analysis. It is found that the measuring precision of thickness is mainly determined by the spectral resolution of spectrometer.

  19. A Dilute-and-Shoot LC-MS Method for Quantitating Opioids in Oral Fluid.

    Science.gov (United States)

    Enders, Jeffrey R; McIntire, Gregory L

    2015-10-01

    Opioid testing represents a dominant share of the market in pain management clinical testing facilities. Testing of this drug class in oral fluid (OF) has begun to rise in popularity. OF analysis has traditionally required extensive clean-up protocols and sample concentration, which can be avoided. This work highlights the use of a fast, 'dilute-and-shoot' method that performs no considerable sample manipulation. A quantitative method for the determination of eight common opioids and associated metabolites (codeine, morphine, hydrocodone, hydromorphone, norhydrocodone, oxycodone, noroxycodone and oxymorphone) in OF is described herein. OF sample is diluted 10-fold in methanol/water and then analyzed using an Agilent chromatographic stack coupled with an AB SCIEX 4500. The method has a 2.2-min LC gradient and a cycle time of 2.9 min. In contrast to most published methods of this particular type, this method uses no sample clean-up or concentration and has a considerably faster LC gradient, making it ideal for very high-throughput laboratories. Importantly, the method requires only 100 μL of sample and is diluted 10-fold prior to injection to help with instrument viability. Baseline separation of all isobaric opioids listed above was achieved on a phenyl-hexyl column. The validated calibration range for this method is 2.5-1,000 ng/mL. This 'dilute-and-shoot' method removes the unnecessary, costly and time-consuming extraction steps found in traditional methods and still surpasses all analytical requirements. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  20. A lumped mass finite element method for vibration analysis of elastic plate-plate structures

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The fully discrete lumped mass finite element method is proposed for vibration analysis of elastic plate-plate structures.In the space directions,the longitudinal displacements on plates are discretized by conforming linear elements,and the transverse displacements are discretized by the Morley element.By means of the second order central difference for discretizing the time derivative and the technique of lumped masses,a fully discrete lumped mass finite element method is obtained,and two approaches to choosing the initial functions are also introduced.The error analysis for the method in the energy norm is established,and some numerical examples are included to validate the theoretical analysis.

  1. Quality of potential harmonics expansion method for dilute Bose–Einstein condensate

    Indian Academy of Sciences (India)

    Anasuya Kundu; Barnali Chakrabarti

    2007-09-01

    We present and examine an approximate but ab initio many-body approach, viz., potential harmonics expansion method (PHEM), which includes two-body correlations for dilute Bose–Einstein condensates. Comparing the total ground state energy for three trapped interacting bosons calculated in PHEM with the exact energy, the new method is shown to be very good in the low density limit which is necessary for achieving Bose–Einstein condensation experimentally.

  2. Study on the Hinge-joined Plate Method

    Directory of Open Access Journals (Sweden)

    Li Sha

    2015-01-01

    Full Text Available In order to verify and perfect the theory of hinge-joined plate method and make it serve the bridge design better, this paper was written based on an actual bridge, and the ANSYS finite element model was established. Compared the hinge-joined plate method results with the analysis results and through the investigation and data analysis, it could be found that the assumption that the hinge-joined plate theory for the board lateral force transmission is reasonable, but the assuming hinge joints that only withstand shear stress and just have the shear checking is unreasonable. At the same time, this paper also proved that the strength reduction getting from the old and new concrete interface should be taken into account when using the hinge-joined plate method to calculate the transverse distribution coefficient and the effects on overall stiffness that the joint depth and thickness of deck pavement to the beam bridge.

  3. Thermal Analysis of Thin Plates Using the Finite Element Method

    Science.gov (United States)

    Er, G. K.; Iu, V. P.; Liu, X. L.

    2010-05-01

    The isotropic thermal plate is analyzed with finite element method. The solution procedure is presented. The elementary stiffness matrix and loading vector are derived rigorously with variation principle and the principle of minimum potential energy. Numerical results are obtained based on the derived equations and tested with available exact solutions. The problems in the finite element analysis are figured out. It is found that the finite element solutions can not converge as the number of elements increases around the corners of the plate. The derived equations presented in this paper are fundamental for our further study on more complicated thermal plate analysis.

  4. Measurement of Infinite Diluted Activity Coefficient of Solvents in Polymer by Inverse Gas Chromatography Method

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    @@1 INTRODUCTION Due to its short experimental time, little sample needed, suitable for broad temperature range, inverse gas chromatography (IGC) has been widely used to measure variety of properties of polymer systems, such as the intinite diluted activity coefficients of solvent in polymer, the glass transition temperature of polymer and the surface properties of polymer[1-5], etc. Those data have been used to develop the group contribution method for the prediction of thermodynamic proper-ties of polymer solution[6].

  5. SPLITTING MODULUS FINITE ELEMENT METHOD FOR ORTHOGONAL ANISOTROPIC PLATE BENGING

    Institute of Scientific and Technical Information of China (English)

    党发宁; 荣廷玉; 孙训方

    2001-01-01

    Splitting modulus variational principle in linear theory of solid mechanics was introduced, the principle for thin plate was derived, and splitting modulus finite element method of thin plate was established too. The distinctive feature of the splitting model is that its functional contains one or more arbitrary additional parameters, called splitting factors,so stiffness of the model can be adjusted by properly selecting the splitting factors. Examples show that splitting modulus method has high precision and the ability to conquer some illconditioned problems in usual finite elements. The cause why the new method could transform the ill-conditioned problems into well-conditioned problem, is analyzed finally.

  6. Method for conducting electroless metal-plating processes

    Science.gov (United States)

    Petit, George S.; Wright, Ralph R.

    1978-01-01

    This invention is an improved method for conducting electroless metal-plating processes in a metal tank which is exposed to the plating bath. The invention solves a problem commonly encountered in such processes: how to determine when it is advisable to shutdown the process in order to clean and/or re-passivate the tank. The new method comprises contacting the bath with a current-conducting, non-catalytic probe and, during plating operations, monitoring the gradually changing difference in electropotential between the probe and tank. It has been found that the value of this voltage is indicative of the extent to which nickel-bearing decomposition products accumulate on the tank. By utilizing the voltage to determine when shutdown for cleaning is advisable, the operator can avoid premature shutdown and at the same time avoid prolonging operations to the point that spontaneous decomposition occurs.

  7. A COMBINED HYBRID FINITE ELEMENT METHOD FOR PLATE BENDING PROBLEMS

    Institute of Scientific and Technical Information of China (English)

    Tian-xiao Zhou; Xiao-ping Xie

    2003-01-01

    In this paper, a combined hybrid method is applied to finite element discretization ofplate bending problems. It is shown that the resultant schemes are stabilized, i.e., theconvergence of the schemes is independent of inf-sup conditions and any other patch test.Based on this, two new series of plate elements are proposed.

  8. Novel boundary element method for resolving plate bending problems

    Institute of Scientific and Technical Information of China (English)

    陈颂英; 王乐勤; 焦磊

    2003-01-01

    This paper discusses the application of the boundary contour method for resolving plate bending problems. The exploitation of the integrand divergence free property of the plate bending boundary integral equation based on the Kirchhoff hypothesis and a very useful application of Stokes' Theorem are presented to convert surface integrals on boundary elements to the computation of bending potential functions on the discretized boundary points, even for curved surface elements of arbitrary shape. Singularity and treatment of the discontinued corner point are not needed at all. The evaluation of the physics variant at internal points is also shown in this article. Numerical results are presented for some plate bending problems and compared against analytical and previous solutions.

  9. Methods for identifying lipoxygenase producing microorganisms on agar plates.

    Science.gov (United States)

    Nyyssölä, Antti; Heshof, Ruud; Haarmann, Thomas; Eidner, Jasmin; Westerholm-Parvinen, Ann; Langfelder, Kim; Kruus, Kristiina; de Graaff, Leo; Buchert, Johanna

    2012-03-26

    Plate assays for lipoxygenase producing microorganisms on agar plates have been developed. Both potassium iodide-starch and indamine dye formation methods were effective for detecting soybean lipoxygenase activity on agar plates. A positive result was also achieved using the β-carotene bleaching method, but the sensitivity of this method was lower than the other two methods. The potassium iodide-starch and indamine dye formation methods were also applied for detecting lipoxygenase production by Trichoderma reesei and Pichia pastoris transformants expressing the lipoxygenase gene of the fungus Gaeumannomyces graminis. In both cases lipoxygenase production in the transformants could be identified. For detection of the G. graminis lipoxygenase produced by Aspergillus nidulans the potassium iodide-starch method was successful. When Escherichia coli was grown on agar and soybean lipoxygenase was applied on the culture lipoxygenase activity could clearly be detected by the indamine dye formation method. This suggests that the method has potential for screening of metagenomic libraries in E. coli for lipoxygenase activity.

  10. Evaluation of method for phthalate extraction from milk related to milk dilution ratio

    Directory of Open Access Journals (Sweden)

    Milojković Danica S.

    2015-01-01

    Full Text Available Liquid-liquid extraction techniques were compared coupled with gas chromatography-mass spectrometry (GC-MS, for the extraction and the determination of four phthalates: dimethyl phthalate (DMP, di-n-butyl phthalate (DBP, benzyl butyl phthalate (BBP and di-(2-ethylhexyl phthalate (DEHP in six different kinds of milk-based samples. Extraction factors: sample preparation, organic solvent type and volume, salt effect, agitation and the extraction time were optimized. The ion of base peaks (m/z 149 for DBP, BBP and DEHP and m/z 163 for DMP for investigated phthalates were selected for the screening studies. The acquisition was performed at the selected ion monitoring mode. The MSD response for GC-MS phthalate calibration standards was linear between 0.25 and 2.50 μg mL-1 with calculated LODs between 0.01 μg mL-1 to 0.04 μg mL-1 and LOQs of 0.05 μg mL-1 to 0.12 μg mL-1, while repeatability was between 1.7 % to 4.9 % RSD. The study demonstrated an increase of the recovery of less polar phthalates in matrix milk standards by matrix dilution. Recovery for hydrophilic phthalates, like DMP, was not changed by matrix dilution and it was continuously low for the investigated method. Two spiking levels were tested for influence of matrix dilution on phthalate recovery, showed the same trend. [Projekat Ministarstva nauke Republike Srbije, br. 31060

  11. Application of optical diffraction method in designing phase plates

    Science.gov (United States)

    Lei, Ze-Min; Sun, Xiao-Yan; Lv, Feng-Nian; Zhang, Zhen; Lu, Xing-Qiang

    2016-11-01

    Continuous phase plate (CPP), which has a function of beam shaping in laser systems, is one kind of important diffractive optics. Based on the Fourier transform of the Gerchberg-Saxton (G-S) algorithm for designing CPP, we proposed an optical diffraction method according to the real system conditions. A thin lens can complete the Fourier transform of the input signal and the inverse propagation of light can be implemented in a program. Using both of the two functions can realize the iteration process to calculate the near-field distribution of light and the far-field repeatedly, which is similar to the G-S algorithm. The results show that using the optical diffraction method can design a CPP for a complicated laser system, and make the CPP have abilities of beam shaping and phase compensation for the phase aberration of the system. The method can improve the adaptation of the phase plate in systems with phase aberrations.

  12. Simpler and More Accurate: Weighing the Mercury in Electrolytic Cells by Radiotracer Dilution Method

    Directory of Open Access Journals (Sweden)

    Sugiharto

    2010-08-01

    Full Text Available Weight of mercury in electrolytic cell of soda industry is usually measured gravimetrically, which is typical labor work in character. Error sources of the gravimetric method might have come from the fact that some mercury’s are usually trapped in the cell due to complicated structure of electrolytic cell. This cause unknown errors. In addition, formation of amalgam at the cathode may cause a further uncertainty in the measurement. Total error from gravimetric method is 4% on average. Radiotracer dilution method provides advantages either for simplification of procedure and reduction of measurement error. In this experiment radioisotope mercury 203Hg, which was prepared in nuclear reactor was used to examine 13 of 14 electrolytic cells of soda plant. Each electrolytic cell was designed containing approximately 700 kg inactive mercury. Before injection, the radioisotope mercury was mixed with non radioisotope mercury in a bath to obtain a suitable injection aliquots and standard references. Calibration curve, which was derived from two stage dilution processes taken from standard references, was used to examine degree of mixing between radioisotope and non radioisotope mercury and it was also used in weight calculation of non radioisotope mercury in electrolytic cell. Injection was carried out simply by pouring the injection aliquots into the flowing mercury at the inlet side of the cell. Mercury samples from the cells were extracted at regular time intervals and filled into vials for counting. This was done for the primary conformation of the completeness of mixing of the tracer with the non radioisotope mercury in each cell. When complete mixing is achieved, the unknown quantity of mercury in each cell was calculated based on mass balance principle. From the calculation the weight of mercury in each electrolytic cell was not the same and maximum error of measurement obtained from this method is 2.48 %. Compared to gravimetrically error

  13. An isotope-dilution standard GC/MS/MS method for steroid hormones in water

    Science.gov (United States)

    Foreman, William T.; Gray, James L.; ReVello, Rhiannon C.; Lindley, Chris E.; Losche, Scott A.

    2013-01-01

    An isotope-dilution quantification method was developed for 20 natural and synthetic steroid hormones and additional compounds in filtered and unfiltered water. Deuterium- or carbon-13-labeled isotope-dilution standards (IDSs) are added to the water sample, which is passed through an octadecylsilyl solid-phase extraction (SPE) disk. Following extract cleanup using Florisil SPE, method compounds are converted to trimethylsilyl derivatives and analyzed by gas chromatography with tandem mass spectrometry. Validation matrices included reagent water, wastewater-affected surface water, and primary (no biological treatment) and secondary wastewater effluent. Overall method recovery for all analytes in these matrices averaged 100%; with overall relative standard deviation of 28%. Mean recoveries of the 20 individual analytes for spiked reagent-water samples prepared along with field samples analyzed in 2009–2010 ranged from 84–104%, with relative standard deviations of 6–36%. Detection levels estimated using ASTM International’s D6091–07 procedure range from 0.4 to 4 ng/L for 17 analytes. Higher censoring levels of 100 ng/L for bisphenol A and 200 ng/L for cholesterol and 3-beta-coprostanol are used to prevent bias and false positives associated with the presence of these analytes in blanks. Absolute method recoveries of the IDSs provide sample-specific performance information and guide data reporting. Careful selection of labeled compounds for use as IDSs is important because both inexact IDS-analyte matches and deuterium label loss affect an IDS’s ability to emulate analyte performance. Six IDS compounds initially tested and applied in this method exhibited deuterium loss and are not used in the final method.

  14. Discharge measurement with salt dilution method in irrigation canals: direct sampling and geophysical controls

    Directory of Open Access Journals (Sweden)

    C. Comina

    2013-08-01

    Full Text Available An important starting point for designing management improvements, particularly in irrigation areas, is to record the baseline state of the water resources, including the amount of discharge from canals. In this respect discharge measurements by means of the salt dilution method is a traditional and well-documented technique. However, this methodology can be strongly influenced by the natural streaming characteristics of the canal (e.g. laminar vs. turbulent flow and accurate precautions must be considered in the choice of both the measuring section and the length of the measuring reach of the canal which can affect the plume shape. The knowledge of plume distribution in the measuring cross-section is of primary importance for a correct location of sampling points aimed in obtaining a reliable measurement. To obtain this, geophysical imaging of an NaCl plume from a slug-injection salt dilution test has been performed within this paper by means of cross-flow fast electric resistivity tomography (FERT in a real case history. Direct sampling of the same plume has been also performed with a multisampling optimization technique to obtain an average value over the measuring section by means of contemporarily sampling water in nine points. Results show that a correct visualization of the passage of the salt plume is possible by means of geophysical controls and that this can potentially help in the correct location of sampling points.

  15. Diffusion behavior of Cr diluted in bcc and fcc Fe: Classical and quantum simulation methods

    Energy Technology Data Exchange (ETDEWEB)

    Ramunni, Viviana P., E-mail: vpram@cnea.gov.ar [CONICET, Avda. Rivadavia 1917, Cdad. de Buenos Aires C.P. 1033 (Argentina); Comisión Nacional de Energía Atómica, Gerencia Materiales, Av. Del Libertador 8250, C1429BNP Ciudad de Buenos Aires (Argentina); Rivas, Alejandro M.F. [CONICET, Avda. Rivadavia 1917, Cdad. de Buenos Aires C.P. 1033 (Argentina); Comisión Nacional de Energía Atómica, Departamento de Física Teórica, Tandar, Av. Del Libertador 8250, C1429BNP Ciudad de Buenos Aires (Argentina)

    2015-07-15

    We characterize the atomic mobility behavior driven by vacancies, in bcc and fcc Fe−Cr diluted alloys, using a multi-frequency model. We calculate the full set of the Onsager coefficients and the tracer self and solute diffusion coefficients in terms of the mean jump frequencies. The involved jump frequencies are calculated using a classical molecular static (CMS) technique. For the bcc case, we also perform quantum calculations based on the density functional theory (DFT). There, we show that, in accordance with Bohr's correspondence principle, as the size of the atomic cell (total number of atoms) is increased, quantum results with DFT recover the classical ones obtained with CMS calculations. This last ones, are in perfect agreement with available experimental data for both, solute and solvent diffusion coefficients. For high temperatures, in the fcc phase where no experimental data are yet available, our CMS calculations predict the expected solute and solvent diffusion coefficients. - Graphical abstract: Display Omitted - Highlights: • Comparison of diffusion coefficients obtained from classical and quantum methods. • We perform our calculations in diluted bcc/fcc Fe–Cr alloy. • Magnetic and phonon effects must be taken into account. • Classical calculations are in perfect agreement with experimental data.

  16. Methodical Specifics of Thermal Experiments with Thin Carbon Reinforced Plates

    Directory of Open Access Journals (Sweden)

    O. V. Denisov

    2015-01-01

    Full Text Available Polymer composite materials (CM are widely used in creation of large space constructions, especially reflectors of space antennas. Composite materials should provide high level of specific stiffness and strength for space structures. Thermal conductivity in reinforcement plane is a significant factor in case of irregular heating space antennas. Nowadays, data on CM reinforcement plane thermal conductivity are limited and existing methods of its defining are imperfect. Basically, traditional methods allow us to define thermal conductivity in perpendicular direction towards the reinforcement plane on the samples of round or rectangular plate. In addition, the thickness of standard samples is larger than space antenna thickness. Consequently, new methods are required. Method of contact heating, which was developed by BMSTU specialists with long hollow carbon beam, could be a perspective way. This article is devoted to the experimental method of contact heating on the thin carbon plates.Thermal tests were supposed to provide a non-stationary temperature field with a gradient being co-directional with the plane reinforcement in the material sample. Experiments were conducted in vacuum chamber to prevent unstructured convection. Experimental thermo-grams processing were calculated by 1-d thermal model for a thin plate. Influence of uncertainty of experimental parameters, such as (radiation emission coefficients of sample surface, glue, temperature sensors and uncertainty of sensors placement on the result of defined thermal conductivity has been estimated. New data on the thermal conductivity in reinforcement plane were obtained within 295 - 375 K temperature range, which can be used to design and develop reflectors of precision space antennas. In the future it is expedient to conduct tests of thin-wall plates from carbon fiber-reinforced plastic in wide temperature range, especially in the low-range temperatures.

  17. Assay of tyrosol and hydroxytyrosol in olive oil by tandem mass spectrometry and isotope dilution method.

    Science.gov (United States)

    Mazzotti, Fabio; Benabdelkamel, Hicham; Di Donna, Leonardo; Maiuolo, Loredana; Napoli, Anna; Sindona, Giovanni

    2012-12-01

    Hydroxytyrosol and tyrosol, the strong antioxidant present in large amount in virgin olive oil have been assayed by LC-MS/MS under MRM condition and isotope dilution method, using d(2)-labelled internal standards obtained by simple synthetic procedures. The assay has been performed under MRM condition monitoring two transitions for each analyte to improve the specificity. This paper deals with a modern approach for assaying the content of this polyphenols in virgin olive oil down to a limit of a few hundreds of parts per billion. Tyrosol and hydroxytyrosol ranged from 10 to 47ppm and from 5 to 25ppm in commercial olive oil, respectively. The accuracy (98-107%) and analytical parameters values confirm the reliability of the proposed approach. The method can be extended to any natural matrices, including mill wastes, after a simple step of sample preparation.

  18. Silver-halide sensitized gelatin (SHSG) processing method for pulse holograms recorded on VRP plates

    Science.gov (United States)

    Evstigneeva, Maria K.; Drozdova, Olga V.; Mikhailov, Viktor N.

    2002-06-01

    One of the most important area of holograph applications is display holography. In case of pulse recording the requirement for vibration stability is easier than compared to CW exposure. At the same time it is widely known that the behavior of sliver-halide holographic materials strongly depends on the exposure duration. In particular the exposure sensitivity drastically decreases under nanosecond pulse duration. One of the effective ways of the diffraction efficiency improvement is SHSG processing method. This processing scheme is based on high modulation of refractive index due to microvoids appearance inside emulsion layer. It should be mentioned that the SHSG method was used earlier only in the cases when the holograms were recorded by use of CW lasers. This work is devoted to the investigation of SHSG method for pulse hologram recording on VRP plates. We used a pulsed YLF:Nd laser with pulse duration of 25 nanoseconds and wavelength of 527 nm. Both transmission and reflection holograms were recorded. The different kinds of bleaching as well as developing solutions were investigated. Our final processing scheme includes the following stages: 1) development in non-tanning solution, 2) rehalogenating bleach, 3) intermediate alcohol drying, 4) uniform second exposure, 5) second development in diluted developer, 6) reverse bleaching, 7) fixing and 8) gradient drying in isopropyl alcohol. Diffraction efficiency of transmission holograms was of about 60 percent and reflection mirror holograms was of about 45 percent. Thus we have demonstrated the SHSG processing scheme for producing effective holograms on VRP plates under pulse exposure.

  19. Numerical Methods for Plate Forming by Line Heating

    DEFF Research Database (Denmark)

    Clausen, Henrik Bisgaard

    2000-01-01

    Line heating is the process of forming originally flat plates into a desired shape by means of heat treatment. Parameter studies are carried out on a finite element model to provide knowledge of how the process behaves with varying heating conditions. For verification purposes, experiments are ca...... are carried out; one set of experiments investigates the actual heat flux distribution from a gas torch and another verifies the validty of the FE calculations. Finally, a method to predict the heating pattern is described....

  20. Combination cellulose plate (non-agar solid support) and agar plate method improves isolation of fungi from soil.

    Science.gov (United States)

    Nonaka, Kenichi; Todaka, Nemuri; Ōmura, Satoshi; Masuma, Rokuro

    2014-11-01

    This is the first report describing the improved isolation of common filamentous fungi via a method combining cellulose plate and agar plate system. A cellulose plate is a porous plate made of nanofibrous crystaline cellulose. Isolating fungi from soils using these types of media separately resulted in the number of fungal colonies appearing on cellulose plates being lower than that on agar plates. However, the number of actual fungal species isolated using cellulose plates alone was more or less the same as that found using agar plates. Significantly, the diversity of isolates using a combination of the two media was greater than using each media individually. As a result, numerous new or rare fungal species with potential, including previously proposed new species, were isolated successfully in this way. All fungal colonies, including the Penicillium species, that appeared on the cellulose plate penetrated in potato dextrose were either white or yellow. Cultivation on cellulose plates with added copper ion overcomes the change in coloration, the colonies appearing as they do following cultivation on potato dextrose agar.

  1. DAFS measurements using the image-plate Weissenberg method

    Energy Technology Data Exchange (ETDEWEB)

    Sugioka, N.; Matsumoto, K.; Sasaki, S. [Tokyo Inst. of Technology, Materials and Structures Lab., Yokohama (Japan); Tanaka, M.; Mori, T. [National Lab. for High Energy Physics, Photon Factory, Tsukuba (Japan)

    1998-05-01

    An instrumental technique for DAFS measurements which can provide site-specific information is proposed. The approach uses (i) focusing optics with parabolic mirrors and a double-crystal monochromator, (ii) the Laue and Bragg settings and (iii) data collection by the image-plate Weissenberg method. Six image exposures are recorded per plate at five intrinsic energies and one reference energy. The single-crystal measurements were performed at the Co K-absorption edge, and the 200, 220 and 311 reflections of CoO and 511 and 911 reflections of Co{sub 3}O{sub 4} were used for analysis. The regression analysis of {chi}(k), Fourier transforms of k{sup 3}{chi}(k) and back-Fourier filtering have been performed. 20 refs.

  2. DAFS measurements using the image-plate Weissenberg method.

    Science.gov (United States)

    Sugioka, N; Matsumoto, K; Tanaka, M; Mori, T; Sasaki, S

    1998-05-01

    An instrumental technique for DAFS measurements which can provide site-specific information is proposed. The approach uses (i) focusing optics with parabolic mirrors and a double-crystal monochromator, (ii) the Laue and Bragg settings and (iii) data collection by the image-plate Weissenberg method. Six image exposures are recorded per plate at five intrinsic energies and one reference energy. The single-crystal measurements were performed at the Co K-absorption edge, and the 200, 220 and 311 reflections of CoO and 511 and 911 reflections of Co(3)O(4) were used for analysis. The regression analysis of chi(k), Fourier transforms of k(3)chi(k) and back-Fourier filtering have been performed.

  3. Should the AOAC use-dilution method be continued for regulatory purposes?

    Science.gov (United States)

    Omidbakhsh, Navid

    2012-01-01

    Despite its very poor reproducibility, AOAC INTERNATIONAL's use-dilution method (UDM) for bactericidal activity (AOAC Methods 964.02, 955.14, and 955.15) has been required by the U.S. Environmental Protection Agency (EPA) since 1953 for regulatory purposes, while methods with better reproducibility have been adopted in Canada and Australia. This study reviews UDM from a statistical perspective. Additionally, the test's expected results were compared to those obtained from actual evaluation of several formulations. Significant gaps have been identified in the reproducibility of the test data as predicted by statistical analysis and those presented to the EPA for product registration. UDM's poor reproducibility, along with its qualitative nature, requires the concentration of the active ingredient to be high enough to ensure all or most carriers to be free of any viable organisms. This is not in accord with the current trends towards sustainability, human safety, and environmental protection. It is recommended that the use of the method for regulatory purposes be phased out as soon as possible, and methods with better design and reproducibility be adopted instead.

  4. Analysis of ochratoxin A in grapes, musts and wines by LC–MS/MS: First comparison of stable isotope dilution assay and diastereomeric dilution assay methods

    Energy Technology Data Exchange (ETDEWEB)

    Roland, Aurélie, E-mail: aurelie@nyseos.fr [Nyseos, 2 place Pierre Viala, Montpellier Cedex 1 34060 (France); Bros, Pauline, E-mail: pauline.bros@gmail.com [Institut Français de la Vigne et du Vin, UMT Qualinnov, 2 place Pierre Viala, Montpellier Cedex 1 34060 (France); Bouisseau, Anaïs, E-mail: anais.bouisseau@gmail.com [Nyseos, 2 place Pierre Viala, Montpellier Cedex 1 34060 (France); Institut des Biomolécules Max Mousseron, UMR-CNRS-5247, Universités Montpellier I and II, Place Eugène Bataillon, 34095 Montpellier (France); Cavelier, Florine, E-mail: florine@univ-montp2.fr [Institut des Biomolécules Max Mousseron, UMR-CNRS-5247, Universités Montpellier I and II, Place Eugène Bataillon, 34095 Montpellier (France); Schneider, Rémi, E-mail: remi.schneider@vignevin.com [Institut Français de la Vigne et du Vin, UMT Qualinnov, 2 place Pierre Viala, Montpellier Cedex 1 34060 (France)

    2014-03-01

    Highlights: • OTA extraction on immunoaffinity columns is not adapted for DIDA quantification. • The use of a labeled internal standard is compulsory to obtain reliable results. • SIDA and DIDA quantification approaches have been compared for the first time. Abstract: Ochratoxin A (OTA) exhibits potent nephrotoxic, carcinogenic and teratogenic effects and its maximum level in wines has been set to 2 μg L⁻¹ by regulation. Consequently, the analytical procedures for OTA determination in wines have to be both very sensitive and reliable. In this paper, we compared two quantification methods: the stable isotope dilution assay (SIDA) and the diastereomeric dilution assay (DIDA). For this purpose, non-natural analogues of OTA were synthesized: the labeled OTA (OTA-d₄) as a diastereomeric mixture for the SIDA and one non-natural OTA’s diastereomer (OTA-dia) for the DIDA. To quantify OTA in red grapes, musts or wines, the sample preparation was optimized using immunoaffinity column extraction and the analysis was performed by LC–MS/MS in Multiple Reaction Monitoring mode. A validation procedure in agreement with the International Organization of Vine and Wine recommendations was conducted. It appeared that SIDA quantification exhibited excellent sensitivity (LOD < 1 ng L⁻¹), accuracy (recovery = 98%), repeatability (RSD < 3%) and intermediate reproducibility (RSD < 4%) compared to quantification by DIDA. Indeed, DIDA method did not provide satisfactory results demonstrating that immunoaffinity extraction is exclusively selective for the natural OTA and not for its diastereomer, which therefore cannot be considered as a good internal standard for this particular method.

  5. Finite strip method combined with other numerical methods for the analysis of plates

    Science.gov (United States)

    Cheung, M. S.; Li, Wenchang

    1992-09-01

    Finite plate strips are combined with finite elements or boundary elements in the analysis of rectangular plates with some minor irregularities such as openings, skew edges, etc. The plate is divided into regular and irregular regions. The regular region is analyzed by the finite strip method while the irregular one is analyzed by the finite element or boundary element method. A special transition element and strip are developed in order to connect the both regions. Numerical examples will show the accuracy and efficiency of this combined analysis.

  6. Screening fungicides for use in fish culture: Evaluation of the agar plug transfer, cellophane transfer, and agar dilution methods

    Science.gov (United States)

    Bailey, Tom A.

    1983-01-01

    The reliability, reproducibility, and usefulness of three screening methods -- the cellophane transfer, the agar plug transfer, and the agar dilution -- to screen aquatic fungicides were evaluated. Achlya flagellata and Saprolegnia hypogyna were exposed to 1, 10, and 100 mg/L of malachite green to test each method. The cellophane transfer and agar plug transfer techniques had similar reliability and reproducibility in rating fungicidal activity, and were both superior to the agar dilution technique. The agar plug transfer and agar dilution techniques adequately projected in vivo activity of malachite green, but the cellophane transfer technique overestimated its activity. Overall, the agar plug transfer technique most accurately rated the activity of malachite green and was the easiest test to perform. It therefore appears to be the method of choice for testing aquatic fungicides.

  7. Comparison of the compact dry TC method with the standard pour plate method (AOAC official method 966.23) for determining aerobic colony counts in food samples: Performance-tested method.

    Science.gov (United States)

    Kodaka, Hidemasa; Mizuochi, Shingo; Teramura, Hajime; Nirazuka, Tadanobu

    2005-01-01

    Compact Dry TC qualifies as a rapid method kit for determining aerobic colony counts in foods. The plates are presterilized and contain culture medium and a cold-soluble gelling agent. The medium is rehydrated by inoculating 1 mL diluted sample into the center of the self-diffusible medium and allowing the solution to diffuse by capillary action. The plates can then be incubated and the colonies counted without any additional steps. The Compact Dry TC method was validated with 5 different raw meats. The performance tests were conducted at 35 degrees and 30 degrees C. In all required performance studies, no apparent differences were observed between the Compact Dry TC method and the Standard Pour Plate method (AOAC Official Method 966.23) for the detection level of aerobic microorganisms. For the accuracy claim (n = 60), a correlation factor of r2(35) = 0.9977 (35 degrees C) and r2(30) = 0.9932 (30 degrees C) could be assigned, as stated in the application for "Performance Tested Method." Quality consistency and storage robustness studies, showed no significant variations in plate count results with different production lots or plates of diverse storage age.

  8. Multi-mycotoxin stable isotope dilution LC-MS/MS method for Fusarium toxins in beer.

    Science.gov (United States)

    Habler, Katharina; Gotthardt, Marina; Schüler, Jan; Rychlik, Michael

    2017-03-01

    A stable isotope dilution LC-MS/MS multi-mycotoxin method was developed for 12 different Fusarium toxins including modified mycotoxins in beer (deoxynivalenol-3-glucoside, deoxynivalenol, 3-acetyldeoxynivalenol, 15-acetyl-deoxynivalenol, HT2-toxin, T2-toxin, enniatin B, B1, A1, A, beauvericin and zearalenone). As sample preparation and purification of beer a combined solid phase extraction for trichothecenes, enniatins, beauvericin and zearalenone was firstly developed. The validation of the new method gave satisfying results: intra-day and inter-day precision and recoveries were 1-5%, 2-8% and 72-117%, respectively. In total, 61 different organic and conventional beer samples from Germany and all over the world were analyzed by using the newly developed multi-mycotoxin method. In summary, deoxynivalenol, deoxynivalenol-3-glucoside, 3-acetyldeoxynivaleneol and enniatin B were quantified in rather low contents in the investigated beer samples. None of the other monitored Fusarium toxins like 15-acetyldeoxynivalenol, HT2- and T2-toxin, zearalenone, enniatin B1, A1, A or beauvericin were detectable.

  9. Simulation of Lamb wave reflections at plate edges using the semi-analytical finite element method.

    Science.gov (United States)

    Ahmad, Z A B; Gabbert, U

    2012-09-01

    In typical Lamb wave simulation practices, effects of plate edge reflections are often not considered in order to simplify the wave signal interpretations. Methods that are based on infinite plates such as the semi-analytical finite element method is effective in simulating Lamb waves as it excludes the effect of plate edges. However, the inclusion of plate edges in a finite plate could render this method inapplicable, especially for transient response simulations. Here, by applying the ratio of Lamb mode reflections at plate edges, and representing the reflection at plate edges using infinite plate solutions, the semi-analytical finite element method can be applied for transient response simulation, even when the plate is no longer infinite.

  10. Enumeration of total aerobic microorganisms in foods by SimPlate Total Plate Count-Color Indicator methods and conventional culture methods: collaborative study.

    Science.gov (United States)

    Feldsine, Philip T; Leung, Stephanie C; Lienau, Andrew H; Mui, Linda A; Townsend, David E

    2003-01-01

    The relative efficacy of the SimPlate Total Plate Count-Color Indicator (TPC-CI) method (SimPlate 35 degrees C) was compared with the AOAC Official Method 966.23 (AOAC 35 degrees C) for enumeration of total aerobic microorganisms in foods. The SimPlate TPC-CI method, incubated at 30 degrees C (SimPlate 30 degrees C), was also compared with the International Organization for Standardization (ISO) 4833 method (ISO 30 degrees C). Six food types were analyzed: ground black pepper, flour, nut meats, frozen hamburger patties, frozen fruits, and fresh vegetables. All foods tested were naturally contaminated. Nineteen laboratories throughout North America and Europe participated in the study. Three method comparisons were conducted. In general, there was count difference in recovery among the SimPlate methods and their corresponding reference methods. Mean log counts between the 2 reference methods were also very similar. Repeatability (Sr) and reproducibility (SR) standard deviations were similar among the 3 method comparisons. The SimPlate method (35 degrees C) and the AOAC method were comparable for enumerating total aerobic microorganisms in foods. Similarly, the SimPlate method (30 degrees C) was comparable to the ISO method when samples were prepared and incubated according to the ISO method.

  11. PLATE

    DEFF Research Database (Denmark)

    Kling, Joyce; Hjulmand, Lise-Lotte

    2008-01-01

    ’s level of English is sufficient for the increasing number of courses offered in English each semester. This paper addresses these concerns and describes a pilot project initiated in 2003 at CBS to gauge the overall English language proficiency of those teaching content courses in English. Through......Copenhagen Business School (CBS) finds itself needing to address the issue of English-medium instruction for its increasing number of foreign exchange and full degree students. With internationalisation as a main pillar of the institution’s agenda, there are concerns whether the teaching faculty...... the Project in Language Assessment for Teaching in English (PLATE) language professionals from CBS’s Language Center observe teachers and provide feedback using evaluation criteria from the Common European Framework for Reference (CEFR) supplemented by some additional criteria which take the LSP nature...

  12. PLATE

    DEFF Research Database (Denmark)

    Kling, Joyce; Hjulmand, Lise-Lotte

    2008-01-01

    Copenhagen Business School (CBS) finds itself needing to address the issue of English-medium instruction for its increasing number of foreign exchange and full degree students. With internationalisation as a main pillar of the institution’s agenda, there are concerns whether the teaching faculty......’s level of English is sufficient for the increasing number of courses offered in English each semester. This paper addresses these concerns and describes a pilot project initiated in 2003 at CBS to gauge the overall English language proficiency of those teaching content courses in English. Through...... the Project in Language Assessment for Teaching in English (PLATE) language professionals from CBS’s Language Center observe teachers and provide feedback using evaluation criteria from the Common European Framework for Reference (CEFR) supplemented by some additional criteria which take the LSP nature...

  13. Mercury speciation analysis in seafood by species-specific isotope dilution: method validation and occurrence data

    Energy Technology Data Exchange (ETDEWEB)

    Clemens, Stephanie; Guerin, Thierry [Agence Nationale de Securite Sanitaire de l' Alimentation, Laboratoire de Securite des Aliments de Maisons-Alfort, Unite des Contaminants Inorganiques et Mineraux de l' Environnement, ANSES, Maisons-Alfort (France); Monperrus, Mathilde; Donard, Olivier F.X.; Amouroux, David [IPREM UMR 5254 CNRS - Universite de Pau et des Pays de l' Adour, Laboratoire de Chimie Analytique Bio-Inorganique et Environnement, Institut des Sciences Analytiques et de Physico-chimie pour l' Environnement et les Materiaux, Pau Cedex (France)

    2011-11-15

    Methylmercury (MeHg) and total mercury (THg) in seafood were determined using species-specific isotope dilution analysis and gas chromatography combined with inductively coupled plasma mass spectrometry. Sample preparation methods (extraction and derivation step) were evaluated on certified reference materials using isotopically enriched Hg species. Solid-liquid extraction, derivation by propylation and automated agitation gave excellent accuracy and precision results. Satisfactory figures of merit for the selected method were obtained in terms of limit of quantification (1.2 {mu}g Hg kg{sup -1} for MeHg and 1.4 {mu}g Hg kg{sup -1} for THg), repeatability (1.3-1.7%), intermediate precision reproducibility (1.5% for MeHg and 2.2% for THg) and trueness (bias error less than 7%). By means of a recent strategy based on accuracy profiles ({beta}-expectation tolerance intervals), the selected method was successfully validated in the range of approximately 0.15-5.1 mg kg{sup -1} for MeHg and 0.27-5.2 mg kg{sup -1} for THg. Probability {beta} was set to 95% and the acceptability limits to {+-}15%. The method was then applied to 62 seafood samples representative of consumption in the French population. The MeHg concentrations were generally low (1.9-588 {mu}g kg{sup -1}), and the percentage of MeHg varied from 28% to 98% in shellfish and from 84% to 97% in fish. For all real samples tested, methylation and demethylation reactions were not significant, except in one oyster sample. The method presented here could be used for monitoring food contamination by MeHg and inorganic Hg in the future to more accurately assess human exposure. (orig.)

  14. Determination of Uranium and Plutonium Concentration in 1AF by Isotopic Dilution Mass Spectrometry Methods

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    <正>It is important data to measure uranium and plutonium concentration for the reprocessing plant control analysis. The determination of uranium and plutonium concentration in 1AF by isotopic dilution mass

  15. A new method to determine the yield stress of diluted polymeric solutions

    Science.gov (United States)

    Soto, Enrique; Ruiz, Servando; Cordova Aguilar, Maria Soledad

    2012-11-01

    A new method to measure the yield stress for diluted polymeric solutions is presented. The tested solutions exhibit shear thinning behavior a once the critical yield stress is overcame. In rheology, these fluids are known as Herschel-Buckley. The yield stress phenomenon and its relation with bubble motion is an important issue for different industries, for example, personal care, paints and some others. As a result of the yield stress, small bubbles remain trapped in the fluid bulk, but above a critical volume, which is related with the characteristic yield stress, the bubbles flow in the liquid. In order to change the bubble volume, the liquid is placed in a cylindrical container whose pressure is decreased by a vacuum pump. The bubble growths as the pressure decreases and keeps its position until it reaches the critical volume. The bubble shape changes with volume and velocity, and a competition among surface, gravitational, inertial and viscous forces is discussed. The yield stress determined value is higher than the obtained from simple shear measurements due to the complex flow around the bubble.

  16. An evaluation of blood smears made by a new method using a spinner and diluted blood.

    Science.gov (United States)

    Nourbakhsh, M; Atwood, J G; Raccio, J; Seligson, D

    1978-12-01

    Blood smears were prepared with the use of a spinner, which rotated with a fixed velocity for a fixed time. All blood samples used for spun smears were diluted with a fixed ratio of buffered isotonic saline solution. Distribution of cells in these smears was found to be random. The average number of cells per unit area was substantially uniform from place to place on the same slide and on multiple slides made with the smae sample. The distribution of leukocytes by type was also iniform. For different blood samples, the average number of cells per unit area in the smears correlated well with the measured cell concentrations per unit volume in the samples for leukocytes, erythrocytes and platelets. Leukocyte differential counts on replicate spun smears using the same bloods also agreed to within the sampling error. They similarly agreed with differential counts on pulled smears made from undiluted samples of the same bloods. With few exceptions, erythrocytic morphology on the spun smears was comparable to that on the good areas of pulled smears made with undiluted samples of the same bloods. Nearly all the spun smears were suitable for both viual and fully automated hematologic examination for leukocytes, erythrocytes, and platelets. This was true over nearly the whole area of each spun slide. In these ways this spinner method makes smears whose consistently high quality is little affected by either the properties of the blood sample or the skill of maker.

  17. Performance of the AOAC use-dilution method with targeted modifications: collaborative study.

    Science.gov (United States)

    Tomasino, Stephen F; Parker, Albert E; Hamilton, Martin A; Hamilton, Gordon C

    2012-01-01

    The U.S. Environmental Protection Agency (EPA), in collaboration with an industry work group, spearheaded a collaborative study designed to further enhance the AOAC use-dilution method (UDM). Based on feedback from laboratories that routinely conduct the UDM, improvements to the test culture preparation steps were prioritized. A set of modifications, largely based on culturing the test microbes on agar as specified in the AOAC hard surface carrier test method, were evaluated in a five-laboratory trial. The modifications targeted the preparation of the Pseudomonas aeruginosa test culture due to the difficulty in separating the pellicle from the broth in the current UDM. The proposed modifications (i.e., the modified UDM) were compared to the current UDM methodology for P. aeruginosa and Staphylococcus aureus. Salmonella choleraesuis was not included in the study. The goal was to determine if the modifications reduced method variability. Three efficacy response variables were statistically analyzed: the number of positive carriers, the log reduction, and the pass/fail outcome. The scope of the collaborative study was limited to testing one liquid disinfectant (an EPA-registered quaternary ammonium product) at two levels of presumed product efficacies, high and low. Test conditions included use of 400 ppm hard water as the product diluent and a 5% organic soil load (horse serum) added to the inoculum. Unfortunately, the study failed to support the adoption of the major modification (use of an agar-based approach to grow the test cultures) based on an analysis of method's variability. The repeatability and reproducibility standard deviations for the modified method were equal to or greater than those for the current method across the various test variables. However, the authors propose retaining the frozen stock preparation step of the modified method, and based on the statistical equivalency of the control log densities, support its adoption as a procedural change to

  18. AN ELECTROPLATING METHOD OF FORMING PLATINGS OF NICKEL, COBALT, NICKEL ALLOYS OR COBALT ALLOYS

    DEFF Research Database (Denmark)

    1997-01-01

    An electroplating method of forming platings of nickel, cobalt, nickel alloys or cobalt alloys with reduced stresses in an electrodepositing bath of the type: Watt's bath, chloride bath or a combination thereof, by employing pulse plating with periodic reverse pulse and a sulfonated naphthalene...... additive. This method makes it possible to deposit nickel, cobalt, nickel or cobalt platings without internal stresses....

  19. Models of convection-driven tectonic plates - A comparison of methods and results

    Science.gov (United States)

    King, Scott D.; Gable, Carl W.; Weinstein, Stuart A.

    1992-01-01

    Recent numerical studies of convection in the earth's mantle have included various features of plate tectonics. This paper describes three methods of modeling plates: through material properties, through force balance, and through a thin power-law sheet approximation. The results obtained are compared using each method on a series of simple calculations. From these results, scaling relations between the different parameterizations are developed. While each method produces different degrees of deformation within the surface plate, the surface heat flux and average plate velocity agree to within a few percent. The main results are not dependent upon the plate modeling method and herefore are representative of the physical system modeled.

  20. Fine particulate speciation profile and emission factor of municipal solid waste incinerator established by dilution sampling method.

    Science.gov (United States)

    Yang, Hsi-Hsien; Luo, Shao-Wei; Lee, Kuei-Ting; Wu, Jhin-Yan; Chang, Chun Wei; Chu, Pei Feng

    2016-08-01

    In this study, fine particulate matter (PM2.5) emitted from a municipal solid waste incinerator (MSWI) was collected using dilution sampling method. Chemical compositions of the collected PM2.5 samples, including carbon content, metal elements, and water-soluble ions, were analyzed. Traditional in-stack hot sampling was simultaneously conducted to compare the influences of dilution on PM2.5 emissions and the characteristics of the bonded chemical species. The results, established by a dilution sampling method, show that PM2.5 and total particulate matter (TPM) emission factors were 61.6 ± 4.52 and 66.1 ± 5.27 g ton-waste(-1), respectively. The average ratio of PM2.5/TPM is 0.93, indicating that more than 90% of PM emission from the MSWI was fine particulate. The major chemical species in PM2.5 included organic carbon (OC), Cl(-), NH4(+), elemental carbon (EC) and Si, which account for 69.7% of PM2.5 mass. OC was from the unburned carbon in the exhaust, which adsorbed onto the particulate during the cooling process. High Cl(-) emission is primarily attributable to wastes containing plastic bags made of polyvinyl chloride, salt in kitchen refuse and waste biomass, and so on. Minor species that account for 0.01-1% of PM2.5 mass included SO4(2-), K(+), Na, K, NO3(-), Al, Ca(2+), Zn, Ca, Cu, Fe, Pb, and Mg. The mean ratio of dilution method/in-stack hot method was 0.454. The contents of water-soluble ions (Cl(-), SO4(2-), NO3(-)) were significantly enriched in PM2.5 via gas-to-particle conversion in the dilution process. Results indicate that in-stack hot sampling would underestimate levels of these species in PM2.5. PM2.5 samples from a municipal solid waste incinerator (MSWI) were collected simultaneously by a dilution sampling technique and a traditional in-stack method. PM2.5 emission factors and chemical speciation profiles were established. Dilution sampling provides more reliable data than in-stack hot sampling. The results can be applied to estimate the PM2

  1. Using the tracer-dilution discharge method to develop streamflow records for ice-affected streams in Colorado

    Science.gov (United States)

    Capesius, Joseph P.; Sullivan, Joseph R.; O'Neill, Gregory B.; Williams, Cory A.

    2005-01-01

    Accurate ice-affected streamflow records are difficult to obtain for several reasons, which makes the management of instream-flow water rights in the wintertime a challenging endeavor. This report documents a method to improve ice-affected streamflow records for two gaging stations in Colorado. In January and February 2002, the U.S. Geological Survey, in cooperation with the Colorado Water Conservation Board, conducted an experiment using a sodium chloride tracer to measure streamflow under ice cover by the tracer-dilution discharge method. The purpose of this study was to determine the feasibility of obtaining accurate ice-affected streamflow records by using a sodium chloride tracer that was injected into the stream. The tracer was injected at two gaging stations once per day for approximately 20 minutes for 25 days. Multiple-parameter water-quality sensors at the two gaging stations monitored background and peak chloride concentrations. These data were used to determine discharge at each site. A comparison of the current-meter streamflow record to the tracer-dilution streamflow record shows different levels of accuracy and precision of the tracer-dilution streamflow record at the two sites. At the lower elevation and warmer site, Brandon Ditch near Whitewater, the tracer-dilution method overestimated flow by an average of 14 percent, but this average is strongly biased by outliers. At the higher elevation and colder site, Keystone Gulch near Dillon, the tracer-dilution method experienced problems with the tracer solution partially freezing in the injection line. The partial freezing of the tracer contributed to the tracer-dilution method underestimating flow by 52 percent at Keystone Gulch. In addition, a tracer-pump-reliability test was conducted to test how accurately the tracer pumps can discharge the tracer solution in conditions similar to those used at the gaging stations. Although the pumps were reliable and consistent throughout the 25-day study period

  2. A method for designing plates in treatments of proximal humeral fracture and distal radial fracture

    Directory of Open Access Journals (Sweden)

    Lin Wang

    2016-11-01

    Full Text Available The purpose of this paper was to quickly design fixation plates for fractured proximal humerus and distal radius according to the requirements of surgical treatment. Therefore, a new method to quickly design cloverleaf plate appropriate for proximal humerus and volar plate appropriate for distal radius is put forward. First, three-dimensional (3D reconstruction models of fractured proximal humerus and distal radius were generated based on deforming mean parametric models of proximal humerus and distal radius, respectively. Second, based on region-of-interest marked on the 3D reconstruction model of proximal humerus and distal radius, abutted surfaces of cloverleaf plate and volar plate were established, respectively. Then, parametric abutted surface was established after setting rational parameters for the surface of the cloverleaf plate. Parametric abutted surface of volar plate was established using the same method. Finally, parametric cloverleaf plate and volar plate are generated through thickening their respective parametric abutted surfaces. The parametric plates, acting as templates, accelerate and simplify the design process and therefore allow users to construct plate with editing valid parameters easily. Group of cloverleaf plates and volar plates with different sizes were generated quickly, showing that the proposed method is feasible and effective.

  3. A New Method for Correcting Vehicle License Plate Tilt

    Institute of Scientific and Technical Information of China (English)

    Mei-Sen Pan; Qi Xiong; Jun-Biao Yan

    2009-01-01

    In the course of vehicle license plate (VLP) automatic recognition, tilt correction is a very crucial process. According to Karhunen-Loeve (K-L) transformation, the coordinates of characters in the image are arranged into a two-dimensional covariance matrix, on the basis of which the centered process is carried out. Then, the eigenvector and the rotation angle α are computed in turn. The whole image is rotated by -α. Thus, image horizontal tilt correction is performed. In the vertical tilt correction process, three correction methods, which are K-L transformation method, the line fitting method based on K-means clustering (LFMBKC), and the line fitting based on least squares (LFMBLS), are put forward to compute the vertical tilt angle θ. After shear transformation (ST) is imposed on the rotated image, the final correction image is obtained. The experimental results verify that this proposed method can be easily implemented, and can quickly and accurately get the tilt angle. It provides a new effective way for the VLP image tilt correction as well.

  4. Evaluation of DAPI direct count, computer assisted and plate count methods

    OpenAIRE

    Chivu, Bogdan

    2010-01-01

    The feasibility of using automatic counting of bacteria stained with highly specific and sensitive fluorescing DNA stain DAPI, 4',6-diamidino-2-phenylindole, and direct manual counting to enumerate both pure culture of Pseudomonas putida overnight culture and sea water enhanced culture, was tested in correlation with plate direct counting, turbidity and absorbance at 600nm, to obtain cross validation. Six diluted samples from overnight pure culture of Pseudomonas putida and sea water culture ...

  5. Antimicrobial susceptibility of Erysipelothrix rhusiopathiae isolated from pigs in Southern Japan with a modified agar dilution method.

    Science.gov (United States)

    Chuma, Takehisa; Kawamoto, Toshio; Shahada, Francis; Fujimoto, Hideki; Okamoto, Karoku

    2010-05-01

    The determination of antimicrobial minimum inhibitory concentration (MIC) in Erysipelothrix rhusiopathiae by using the agar dilution method has not been covered by the Clinical and Laboratory Institute (CLSI). Only the broth microdilution method has been outlined. This report describes a modification of the agar dilution procedure for E. rhusiopathiae using Trypto-soy agar supplemented with 0.1% Tween 80 and incubation in ambient air at 37 degrees C for 24 hr. The MICs of the assay were in agreement with those of the broth microdilution method recommended by the CLSI. Antimicrobial susceptibility test was performed using this method for 149 E. rhusiopathiae isolates from 2 meat processing plants in Kagoshima Prefecture during the period of April 2004 to March 2005. The number of strains resistant to oxytetracycline, erythromycin, lincomycin, ofloxacin and enrofloxacin were 56 (37.6%), 4 (2.7%), 18 (12.1%), 21 (14.1%) and 19 (12.8%), respectively. All strains were susceptible to ampicillin.

  6. Isotope-dilution TurboFlow-LC-MS/MS method for simultaneous quantification of ten steroid metabolites in serum

    DEFF Research Database (Denmark)

    Søeborg, Tue; Frederiksen, Hanne; Johannsen, Trine Holm

    2017-01-01

    An isotope-dilution TurboFlow-LC-MS/MS method for simultaneous quantification of the ten steroid metabolites dehydroepiandrosterone sulfate (DHEAS), progesterone, 17α-hydroxyprogesterone (17-OHP), Δ4-androstenedione (Adione), corticosterone, 11-deoxycortisol, cortisol, cortisone, testosterone (T)...... possible only to include some of these analytes for specific diagnostic purposes which make the new method an extremely useful tool in the clinical laboratory....

  7. Investigation of acoustic field near to elastic thin plate using integral method

    Directory of Open Access Journals (Sweden)

    В.І. Токарев

    2004-01-01

    Full Text Available  Investigation of acoustic field near to elastic thin plate using  integral method The influence of boundary conditions on sound wave propagation, radiation and transmission through thin elastic plate is investigated. Necessary for that numerical model was found using the Helmholtz equation and equation of oscilated plate by means of integral formulation of the solution for acoustic fields near to elastic thin plate and for bending waves of small amplitudes.

  8. Energy flow in plate assembles by hierarchical version of finite element method

    DEFF Research Database (Denmark)

    Wachulec, Marcin; Kirkegaard, Poul Henning

    method has been proposed. In this paper a modified hierarchical version of finite element method is used for modelling of energy flow in plate assembles. The formulation includes description of in-plane forces so that planes lying in different planes can be modelled. Two examples considered are: L......-corner of two rectangular plates an a I-shaped plate girder made of five plates. Energy distribution among plates due to harmonic load is studied and the comparison of performance between the hierarchical and standard finite element formulation is presented....

  9. Development of optimization method for plate heat exchanger with undulation

    Directory of Open Access Journals (Sweden)

    Dvořák Václav

    2016-01-01

    Full Text Available The article deals with optimization of undulated heat transfer surface of plate heat exchanger. The goal of optimization is not only to increase effectiveness of heat transfer but also to reduce the pressure drop. A combined pattern of undulation which combines herringbone pattern and wavy pattern was optimized and best values of four parameters were found; angle of herringbone pattern, number, phase and amplitude of longitudinal waves of wavy pattern. The optimization procedure looked for maximum of objective function which was a linear combination of effectiveness and pressure drop. We used simple Monte Carlo method and the optimum was searched for four values of reference pressure drop. Four different optimization were run and we investigated the effect of various definition of objective function and parameters of undulation. It was found that during optimization of combined pattern, the herringbone pattern is more favoured than wavy pattern. It is caused by the fact that herringbone pattern was described by the only one free parameter, which was the angle of undulation, and therefore it is more likely to be found by a stochastic method. This assumption was confirmed when simple wavy pattern was optimized and higher values of objective function and effectiveness were found.

  10. Hydrophobic grid membrane filter method for aerobic plate count in foods: collaborative study.

    Science.gov (United States)

    Entis, P

    1986-01-01

    Twenty-one laboratories participated in a collaborative study to validate a hydrophobic grid membrane filter (HGMF) method for aerobic plate count by comparing its performance against the AOAC/APHA pour plate method. Raw milk, raw poultry, whole egg powder, flours, and spices were included in the study. Counts obtained by the HGMF and pour plate methods did not differ significantly, except in the case of whole egg powder, for which the HGMF method produced significantly higher counts. The hydrophobic grid membrane filter method for aerobic plate count in foods has been adopted official first action.

  11. Diluted melt proton exchange slab waveguides in LiNbO3: A new fabrication and characterization method

    DEFF Research Database (Denmark)

    Veng, Torben; Skettrup, Torben

    1997-01-01

    A method of dilute-melt proton exchange employing a mixture of glycerol and KHSO4 with lithium benzoate added is used to fabricate planar waveguides in c-cut LiNbO3. With this exchange melt system the waveguide refractive index profiles can be fabricated with a high degree of reproducibility. In ...... refractive index change and composition of this glycerol, KHSO4 and lithium benzoate exchange melt system....

  12. Research on Transverse Acetabular Fracture Fixation Using Different Plate Attachment Methods

    Directory of Open Access Journals (Sweden)

    Gediminas Gaidulis

    2015-03-01

    Full Text Available The article deals with the problem of transverse acetabular fracture fixation using different plate attachment methods. A 3D model of pelvis and hip joint structure was created and the design of three different fixation plates using SolidWorks was made. The plates were fixed at distances of 10, 20 and 30 mm from the acetabulum. The model was meshed into finite elements, a static external load of 2500 N was added and the analysis of stress distribution in plates and fracture displacement was performed. The obtained results showed that fracture displacement was quite similar in all fixation methods. However, the maximal stress in the nearest from the acetabulum plate was higher than yield strength. Thus, this placement is not eligible. The plate fixed at a distance of 30 mm from the acetabulum appeared the most suitable because of the smallest and symmetrical stress distribution in the plate.

  13. USDA FSIS and FDA BAM culture methods BBL CHROMagar Salmonella prepared plated and Difco dehydrated culture media.

    Science.gov (United States)

    Ritter, Vicki; Dick, Nancy

    2009-01-01

    BBL and Difco CHROMagar Salmonella (CS) was evaluated internally and externally for the recovery of Salmonella in raw chicken, raw ground beef, raw fish, lettuce, and shell eggs. The raw chicken and ground beef were processed according to the U.S. Department of Agriculture, Food Safety and Inspection Service reference methods. The raw fish, lettuce, and shell eggs were processed according to the U.S. Food and Drug Administration, Bacteriological Analytical Manual procedures. Only raw chicken was found to be naturally contaminated with Salmonella; all other matrixes were seeded with an appropriate dilution of organism to achieve fractionally positive results. Salmonella strains were permitted to equilibrate with the culture-negative matrixes for 48 h at 4 degrees C. Twenty 25 g samples of each food matrix plus 5 uninoculated samples were processed. CS prepared plates (CS PPM) and laboratory prepared plates from dehydrated culture media (CS DCM) were evaluated with the reference method media. A total of 16 positive cultures were obtained from the raw chicken samples, 17 in the raw ground beef, 18 in the raw fish and lettuce, and 11 in the shell eggs. A Chi-square analysis was performed on each of the food matrixes. BBL CS produced comparable results with the reference methods on all matrixes, resulting in a method agreement of 100% based on the Chi-square results. In testing known isolates the sensitivity and specificity was determined to be 94%. Specificity improved to 98% when tetrathionate broth enrichment was used. A negative- and false-positive rate of 6% was found with known isolates. No false negatives were found in testing the food matrixes. The performance of the CS prepared plate and laboratory prepared plate was identical.

  14. Semi-Analytical Finite Strip Transfer Matrix Method for Buckling Analysis of Rectangular Thin Plates

    Directory of Open Access Journals (Sweden)

    Li-Ke Yao

    2015-01-01

    Full Text Available Plates and shells are main components of modern engineering structures, whose buckling analysis has been focused by researchers. In this investigation, rectangular thin plates with loaded edges simply supported can be discretized by semi-analytical finite strip technology. Then the control equations of the strip elements of the buckling plate will be rewritten as the transfer equations by transfer matrix method. A new approach, namely semi-analytical Finite Strip Transfer Matrix Method, is developed for the buckling analysis of plates. This method requires no global stiffness matrix of the system, reduces the system matrix order, and improves the computational efficiency. Comparing with some theoretical results and FEM’s results of two illustrations (the plates and the ribbed plates under six boundary conditions, the method is proved to be reliable and effective.

  15. The Brazilian dilution method for ballast water exchange; O metodo de diluicao brasileiro para troca de agua de lastro

    Energy Technology Data Exchange (ETDEWEB)

    Mauro, Celso Alleluia [PETROBRAS, Rio de Janeiro, RJ (Brazil). Centro de Pesquisas. Avaliacao e Monitoramento Ambiental]. E-mail: celso@cenpes.petrobras.com.br; Land, Claudio Goncalves [PETROBRAS, Rio de Janeiro, RJ (Brazil). Abastecimento, Logistica e Planejamento]. E-mail: cgland@petrobras.com.br; Pimenta, Jose Maria Hollanda Alvares; Barreto, Francisco Carlos Peixoto [PETROBRAS, Rio de Janeiro, RJ (Brazil). Engenharia; Brandao, Marcus Vinicius Lisboa; Marroig, Nilton Lemos [Transpetro, Rio de Janeiro, RJ (Brazil). Frota Nacional de Petroleiros. Inspetoria Geral; Tristao, Maria Luiza Braganca [PETROBRAS, Rio de Janeiro, RJ (Brazil). Centro de Pesquisas. Quimica; Fadel, Andre Luiz da Fonseca [PETROBRAS, Rio de Janeiro, RJ (Brazil). Financas Corporativa e Tesouraria; Villac, Maria Celia; Fernandes, Lohengrin; Paranhos, Rodolfo; Dias, Cristina; Bonecker, Sergio; Denise Tenenbaum [Universidade Federal, Rio de Janeiro, RJ (Brazil). Inst. de Biologia; Persich, Graziela; Garcia, Virginia; Odebrecht, Clarisse [Fundacao Universidade do Rio Grande, RS (Brazil). Dept. de Oceanografia

    2002-12-01

    In a precautionary approach and dealing with the coming International Maritime Organization (IMO) regulations on ballast water, PETROBRAS developed a new method for ballast water exchange in tankers. Differently from ordinary methods PETROBRAS method which have been called Brazilian Dilution Method (BDM) or Dilution Method involves ballast loading through the top with simultaneous unloading from the bottom of the tanks. The method proposal was firstly presented to IMO, which encouraged PETROBRAS to carry out a field trial. PETROBRAS in June 1998 carried out a trial in the product carrier M/V Lavras. A simulation study was useful to plan the trial assessing the theoretical efficiency of the method, establishing the best sampling points and comparing the BDM with the Tank Overfilling Method (TOM). Simulation showed that for the same tank shape, the water renewal in BDM is more effective than in TOM and that 90 % of water renewal could be obtained by BDM. A dye concentration variation monitoring and a biological assessment were performed and the results confirmed that over than 90 % of the ballast water was renewed after three exchanges. The method was proved safe, practical, economical and suitable to minimize the risk of exotic species transport between ports. (author)

  16. Analysis of thin plates by the weak form quadrature element method

    Institute of Scientific and Technical Information of China (English)

    ZHONG HongZhi; YUE ZhiGuang

    2012-01-01

    The recently proposed weak form quadrature element method (QEM) is applied to flexural and vibrational analysis of thin plates.The integrals involved in the variational description of a thin plate are evaluated by an efficient numerical scheme and the partial derivatives at the integration sampling points are then approximated using differential quadrature analogs.Neither the grid pattern nor the number of nodes is fixed,being adjustable according to convergence need.The C1 continuity conditions characterizing the thin plate theory are discussed and the robustness of the weak form quadrature element for thin plates against shape distortion is examined.Examples are presented and comparisons with analytical solutions and the results of the finite element method are made to demonstrate the convergence and computational efficiency of the weak form quadrature element method.It is shown that the present formulation is applicable to thin plates with varying thickness as well as uniform plates.

  17. FREE VIBRATION OF ANISOTROPIC RECTANGULAR PLATES BY GENERAL ANALYTICAL METHOD

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    According to the differential equation for transverse displacement function of anisotropic rectangular thin plates in free vibration, a general analytical solution is established. This general solution, composed of the composite solutions of trigonometric function and hyperbolic function, can satisfy the problem of arbitrary boundary conditions along four edges. The algebraic polynomial with double sine series solutions can also satisfy the problem of boundary conditions at four corners. Consequently, this general solution can be used to solve the vibration problem of anisotropic rectangular plates with arbitrary boundaries accurately. The integral constants can be determined by boundary conditions of four edges and four corners. Each natural frequency and vibration mode can be solved by the determinate of coefficient matrix from the homogeneous linear algebraic equations equal to zero. For example, a composite symmetric angle ply laminated plate with four edges clamped has been calculated and discussed.

  18. Biomechanical Evaluation of the Fixation Methods for Transcondylar Fracture of the Humerus:ONI Plate Versus Conventional Plates and Screws

    Directory of Open Access Journals (Sweden)

    Shimamura,Yasunori

    2010-04-01

    Full Text Available

    We biomechanically evaluated the bone fixation rigidity of an ONI plate (Group I during fixation of experimentally created transcondylar humerus fractures in cadaveric elbows, which are the most frequently observed humeral fractures in the elderly, and compared it with the rigidity achieved by 3 conventional fixation methods:an LCP reconstruction plate 3.5 using a locking mechanism (Group II, a conventional reconstruction plate 3.5 (CRP with a cannulated cancellous screw (Group III, and a CRP with 2 cannulated cancellous screws (CS in a crisscross orientation (Group IV. In the axial loading test, the mean failure loads were:Group I, 98.9+/-32.6;Group II, 108.5+/-27.2;Group III, 50.0+/-7.5;and Group IV, 34.5+/-12.2 (N. Group I fixations failed at a significantly higher load than those of Groups III and IV (p0.05. In the extension loading test, the mean failure loads were:Group I, 34.0+/-12.4;Group II, 51.0+/-14.8;Group III, 19.3+/-6.0;and Group IV, 14.7+/-3.1 (N. Group IV fixations showed a significantly lower failure load than those of Group I (p0.05. The fixation rigidities against mechanical loading by the ONI plate and LCP plate were comparable. These results suggested that an ONI system might be superior to the CRP and CS method, and comparable to the LCP method in terms of fixation rigidity for distal humerus fractures.

  19. Ceramic hot plate and method for its manufacture

    NARCIS (Netherlands)

    Noordhoek, M.J.; Van den Heuvel, R.C.; Kelder, E.M.; Schoonman, J.

    2000-01-01

    The subject is a hot plate comprising at least one cooking zone of ceramic material to be located above a heat source of a cooking range. The cooking zone consists of a ceramic material exhibiting a Mott transition. The material exhibiting a Mott transition may consist of a primary ceramic material,

  20. THE METHOD OF REMOVAL YTTRIUM (III AND YTTERBIUM (III FROM DILUTE AQUEOUS SOLUTIONS

    Directory of Open Access Journals (Sweden)

    Olga Lobacheva

    2016-04-01

    Full Text Available Yttrium (III and ytterbium (III cations ion flotation from diluted aqueous solutions in the presence of chloride ions using sodium dodecyl sulfate as collector agent were studied. Y (III and Yb (III distribution and recovery coefficients as a function of aqueous phase рН value at different sodium chloride concentrations were received. Yttrium (III and ytterbium (III chloro and hydroxo complexes instability constants were calculated. The calculation of separation coefficient at рН specified values depending on chloride ion concentration was conducted. Maximum separation coefficient was observed when chloride concentration of 0.01 M is 50 at рН 7.8. Ksep is minimal in nitrate medium ans is 3 at рН 7.0. At sodium chloride concentration of 0.05 М Ksep is 9 at рН 7.8.

  1. New method for solving the bending problem of rectangular plates with mixed boundary conditions

    Directory of Open Access Journals (Sweden)

    Liu Xin Min

    2016-01-01

    Full Text Available A new method is used to solve the rectangular plate bending problem with mixed boundary conditions. The method overcomes the complicated derivation of the classical solution by Fourth-order differential problem into integrating question. Under uniform loading rectangular plate bending problem with one side fixed the opposite side half simply supported half fixed the other two sides free rectangular plate, one side simply supported the opposite side half simply supported half fixed the other two sides free rectangular plate is systematically solved. According to the actual boundary conditions of the rectangular plate, the corresponding characteristic equation can easily be set up. It is presented deflection curve equation and the numerical calculation. By compared the results of the equation to the finite element program, we are able to demonstrate the correctness of the method. So the method not only has certain theoretical value, but also can be directly applied to engineering practice.

  2. A Novel Morphological Method for Detection and Recognition of Vehicle License Plates

    Directory of Open Access Journals (Sweden)

    S. H.M. Kasaei

    2009-01-01

    Full Text Available Problem statement: License plate detection and recognition is an image-processing technique used to identify a vehicle by its license plate. This notable technology has got multiple applications in various traffic and security cases. To name but a few, toll roads, border control, security and car tracking are same of its applications. The main stage is the isolation of the license plate, from the digital image of the car obtained by a digital camera under different circumstances such as illumination, slop, distance and angle. Approach: This study presented a novel method of identifying and recognizing license plates based on the morphology and template matching. The algorithm started with reprocessing and signal conditioning. Next license plate is localized using morphological operators. Then a template matching scheme will be used to recognize the digits and characters within the plate. Results: The system was tested on Iranian car plate images and the performance was 97.3% of correct plates identification and localization and 92% of correct recognized characters. The results regarding the complexity of the problem and diversity of the test cases showed the high accuracy and robustness of the proposed method. The method could also be applicable for other applications in the transport information systems, where automatic recognition of registration plates, shields, signs and so on is often necessary. Conclusion: This system was customized for the identification of Iranian license plates. The results showed that this algorithm performs well on different types of vehicles including Iranian car and motorcycle plates as well as diverse circumstances. We believe that this system can be redesigned and tested for multi national car license plates in the future time regarding their own attributes.

  3. Spiral plate count method for the examination of raw and pasteurized milk.

    Science.gov (United States)

    Donnelly, C B; Gilchrist, J E; Peeler, J T; Campbell, J E

    1976-07-01

    The spiral plate count method (SPLPC) was compared with the standard plate count (SPC) method by examining 201 samples of raw and pasteurized milk. Although the means of the two methods differed significantly at alpha = 0.01,the difference was less than 10% and was not considered to be of any practical importance. The pooled replicate variances of both methods were less than 0.003, indicating good agreement between duplicate plates, with the variance of the SPLPC slightly less than that of the SPC. We believe this study indicates that the SPLPC could be substituted for the SPC in the bacteriological examination of milk.

  4. The constraint method: A new finite element technique. [applied to static and dynamic loads on plates

    Science.gov (United States)

    Tsai, C.; Szabo, B. A.

    1973-01-01

    An approch to the finite element method which utilizes families of conforming finite elements based on complete polynomials is presented. Finite element approximations based on this method converge with respect to progressively reduced element sizes as well as with respect to progressively increasing orders of approximation. Numerical results of static and dynamic applications of plates are presented to demonstrate the efficiency of the method. Comparisons are made with plate elements in NASTRAN and the high-precision plate element developed by Cowper and his co-workers. Some considerations are given to implementation of the constraint method into general purpose computer programs such as NASTRAN.

  5. Test Method for High β Particle Emission Rate of 63Ni Source Plate

    Directory of Open Access Journals (Sweden)

    ZHANG Li-feng

    2015-01-01

    Full Text Available For the problem of measurement difficulties of β particle emission rate of Ni-63 source plate used for Ni-63 betavoltaic battery, a relative test method of scintillation current method was erected according to the measurement principle of scintillation detector.β particle emission rate of homemade Ni-63 source plate was tested by the method, and the test results were analysed and evaluated, it was initially thought that scintillation current method was a feasible way of testing β particle emission rate of Ni-63 source plate with high β particle emission rate.

  6. The effect of semen collection method and level of egg yolk on capability of dilution and storage of buck semen

    Directory of Open Access Journals (Sweden)

    N.N. Dhaher

    2013-12-01

    Full Text Available The study was conducted to evaluate the effect of semen collection method for reduction of the deleterious interaction between the enzymes of bulbourethral gland and egg yolk during the dilution and storage of buck semen by three different level of egg yolk. Ten bucks were used in this study; the bucks were divided into two groups (five bucks in each group. Semen samples were collected once a week for four weeks from the bucks in first group using an artificial vagina, and from the animals in second group using an electroejaculator. The collected semen samples were diluted with sodium citrate extender with three different level of egg yolk (5, 10 and 20%. Extend semen samples were stored at 5 °C for three days. Computer assisted sperm analysis and Sperm Class Analyzer® were used for evaluation of the buck semen samples. Sperm motility parameters were evaluated which includes; percentage of motile sperm, percentage of progressive motile sperm, the value of the linear velocity (VSL, the value of the average velocity (VAP, the value of the curvilinear velocity (VCL, and the amplitude of lateral movement of the head (ALH. Results showed that all sperm motility parameters under the different level of egg yolk in semen samples that collected by artificial vagina were significantly higher than those which collected by electroejaculator. The percentage of motile sperm and progressive motile sperm of samples that collected by artificial vagina were higher at 10% of egg yolk, while these motility parameters were higher at 5% of egg yolk for semen samples that collected by electroejaculator. The differences between the two methods of semen collection in VCL and ALH were clear and the values were higher in samples that collected using the artificial vagina. The values of VSL, VAP and VCL of semen samples that collected by artificial vagina were higher at the second day than first day of semen storage under 10% of egg yolk. In conclusion, there are effects

  7. A License Plate Locating Method Based on Tophat-bothat Changing and Line Scanning

    Energy Technology Data Exchange (ETDEWEB)

    Hou, P G; Zhao, J; Liu, M [Electrical Engineering Institute of Yanshan University, QinHuangdao, Hebei (China)

    2006-10-15

    The automatic license plate recognition is an important technique to obtain traffic information, it mixes computer vision, image processing techniques and pattern recognition techniques, it is an important technique in intelligent traffic system. In a vehicle license plate recognition system, plate region detection is the key step before the final recognition. This article introduces the whole process of plate region detection. Top - hat and bot - hat transformation are used for enhancing the image contrast in this paper, and wavelet threshold method is used as image filter, and a improved line scanning is used for plate region detection at last. This method has strong practicability. The experimental results demonstrate that the method introduced in this paper is effective.

  8. Development of an Isotope-Dilution Liquid Chromatography/Mass Spectrometric Method for the Accurate Determination of Acetaminophen in Tablets

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Hyun Ju; Kim, Byung Joo; Lee, Joon Hee; Hwang, Eui Jin [Korea Research Institute of Standards and Science, Daejeon (Korea, Republic of)

    2010-12-15

    Acetaminophen (N-acetyl-p-aminophenol) is one of the most popular analgesic and antipyretic drugs. An isotope dilution mass spectrometric method based on LC/MS was developed as a candidate reference method for the accurate determination of acetaminophen in pharmaceutical product. After spiking an isotope labeled acetaminophen (acetyl-{sup 13}C{sub 2}, {sup 15}Nacetaminophen) as an internal standard, tablet extracts were analyzed by LC/MS in a selected reaction monitoring (SRM) mode to detect ions at m/z 152→110 and m/z 155→111 for acetaminophen and acetyl-{sup 13}C{sub 2}, {sup 15}N-acetaminophen, respectively. The repeatability and reproducibility of the developed ID/LC-MS method were tested for the validation and assessment of metrological quality of the method.

  9. Ice-affected streamflow records using tracer-dilution discharge methods

    Science.gov (United States)

    Capesius, J.P.; Sullivan, J.R.; Williams, C.A.; O'Neill, G. B.; ,

    2002-01-01

    Accurate ice-affected streamflow records are difficult to obtain for several reasons. Problems measuring stage, variable backwater conditions, access limitations in wintertime, and problems measuring flowing water under ice cover all contribute to make ice-affected streamflow records less accurate than open-channel streamflow records. The inaccuracy of ice-affected streamflow records is particularly troublesome for small streams where Instream-Flow water rights exist. The Colorado Water Conservation Board uses these water rights to protect in-stream aquatic communities. In January and February 2002, the U.S. Geological Survey, in cooperation with the Colorado Water Conservation Board, conducted an experiment using a sodium chloride tracer to determine streamflow under ice cover. The purpose of this study is to determine the usefulness and accuracy of ice-affected streamflow records using a sodium chloride tracer that was automatically injected into the stream. The tracer was injected at two gaging stations once per day for up to 25 days. Multiple-parameter water-quality sensors at the two gaging stations monitored background and peak tracer concentrations and conductance. These data were used to determine discharge at each site. A comparison of current-meter measurements to tracer-dilution discharge measurements shows an underestimation of discharge due to inaccuracy of current-meter measurements with ice cover and inconsistent tracer-pump rates caused by partial freezing of the tracer solution in the injection lines.

  10. Physical chemical and citotoxic evaluation of highly diluted solutions of Euphorbia tirucalli L. prepared through the fifty milesimal homeopathic method

    Directory of Open Access Journals (Sweden)

    Carlos Renato Zacharias

    2010-07-01

    Full Text Available Background: although Hahnemann described the fifty-milesimal (LM method in the 6th edition of the Organon of the Medical Art, very little research has been carried out on the physical chemical properties of these homeopathic preparations. Furthermore, there is still no evidence allowing for the correlation between the alleged physical chemical properties and the biological effects of high dilutions. Aims: to evaluate physical chemical characteristics of LM preparations including electrical conductivity, pH and refraction index, and their effect on biological experimental models. Materials and methods: preparations tested for physical chemical analysis were dilutions 1 lm to 10 lm of Euphorbia tirucalli L. prepared from the latex and the juice of the plant. To rule the seasonal characteristics of this plant, 2 different populations were used, one collected in June 2007 and the other in May 2008. Furthermore, the cytotoxic effect of Euphorbia tirucalli 5 lm was tested on human breast cancer cells (MCF7 through MTT assay. Some differences among the two collections were observed. However, any clear correlation could be observed between physical chemical properties and biological activity.

  11. A comparison between orthogonal and parallel plating methods for distal humerus fractures: a prospective randomized trial.

    Science.gov (United States)

    Lee, Sang Ki; Kim, Kap Jung; Park, Kyung Hoon; Choy, Won Sik

    2014-10-01

    With the continuing improvements in implants for distal humerus fractures, it is expected that newer types of plates, which are anatomically precontoured, thinner and less irritating to soft tissue, would have comparable outcomes when used in a clinical study. The purpose of this study was to compare the clinical and radiographic outcomes in patients with distal humerus fractures who were treated with orthogonal and parallel plating methods using precontoured distal humerus plates. Sixty-seven patients with a mean age of 55.4 years (range 22-90 years) were included in this prospective study. The subjects were randomly assigned to receive 1 of 2 treatments: orthogonal or parallel plating. The following results were assessed: operating time, time to fracture union, presence of a step or gap at the articular margin, varus-valgus angulation, functional recovery, and complications. No intergroup differences were observed based on radiological and clinical results between the groups. In our practice, no significant differences were found between the orthogonal and parallel plating methods in terms of clinical outcomes, mean operation time, union time, or complication rates. There were no cases of fracture nonunion in either group; heterotrophic ossification was found 3 patients in orthogonal plating group and 2 patients in parallel plating group. In our practice, no significant differences were found between the orthogonal and parallel plating methods in terms of clinical outcomes or complication rates. However, orthogonal plating method may be preferred in cases of coronal shear fractures, where posterior to anterior fixation may provide additional stability to the intraarticular fractures. Additionally, parallel plating method may be the preferred technique used for fractures that occur at the most distal end of the humerus.

  12. A Novel Separation Method of Microthrix parvicella Filaments from Activated Sludge by a Hydrophobic Plate.

    Science.gov (United States)

    Fei, Xuening; Li, Songya; Cao, Lingyun; Yan, Weiguo; Ma, Huaji; Jia, Guozhi

    2015-10-01

    The aim of this paper is to develop a novel method to separate Microthrix parvicella (M. parvicella) filaments from activated sludge easily and quickly, as there are a few difficulties in the isolation of M. parvicella filaments, such as complicated isolation process, time consuming, etc. In this work, a series of hydrophobic plate with and without microchannels have been prepared for the separation of M. parvicella filaments. The results showed that the presence of microchannels and hydrophobic property of the hydrophobic plates affected the separation efficiency of M. parvicella significantly. The scanning electron microscope and Keyence Digital Microscope analysis results showed that the diameter of microchannels was similar to the width of M. parvicella filament, which was beneficial for the fastening of M. parvicella filaments on the plate. The hydrophobic property of the prepared plates was tested by contact angle of water droplets, and the results displayed that the polydimethylsiloxane (PDMS) plate possessed the highest contact angle compared with that of other plates, like polymethylmethacrylate, polystyrene plate, and PDMS plate with no hydrophobic microchannels. Thus, it was concluded that the high separation efficiency of PDMS plates to M. parvicella filaments was due to its best hydrophobic property.

  13. Energy flow in plate assembles by hierarchical version of finite element method

    DEFF Research Database (Denmark)

    Wachulec, Marcin; Kirkegaard, Poul Henning

    method has been proposed. In this paper a modified hierarchical version of finite element method is used for modelling of energy flow in plate assembles. The formulation includes description of in-plane forces so that planes lying in different planes can be modelled. Two examples considered are: L......The dynamic analysis of structures in medium and high frequencies are usually focused on frequency and spatial averages of energy of components, and not the displacement/velocity fields. This is especially true for structure-borne noise modelling. For the analysis of complicated structures......-corner of two rectangular plates an a I-shaped plate girder made of five plates. Energy distribution among plates due to harmonic load is studied and the comparison of performance between the hierarchical and standard finite element formulation is presented....

  14. Soil plate bioassay: an effective method to determine ecotoxicological risks.

    Science.gov (United States)

    Boluda, R; Roca-Pérez, L; Marimón, L

    2011-06-01

    Heavy metals have become one of the most serious anthropogenic stressors for plants and other living organisms. Having efficient and feasible bioassays available to assess the ecotoxicological risks deriving from soil pollution is necessary. This work determines pollution by Cd, Co, Cr, Cu, Ni, Pb, V and Zn in two soils used for growing rice from the Albufera Natural Park in Valencia (Spain). Both were submitted to a different degree of anthropic activity, and their ecotoxicological risk was assessed by four ecotoxicity tests to compare their effectiveness: Microtox test, Zucconi test, pot bioassay (PB) and soil plate bioassay (SPB). The sensitivity of three plant species (barley, cress and lettuce) was also assessed. The results reveal a different degree of effectiveness and level of inhibition in the target organisms' growth depending on the test applied, to such an extent that the one-way analysis of variance showed significant differences only for the plate bioassay results, with considerable inhibition of root and shoot elongation in seedlings. Of the three plant species selected, lettuce was the most sensitive species to toxic effects, followed by cress and barley. Finally, the results also indicate that the SPB is an efficient, simple and economic alternative to other ecotoxicological assays to assess toxicity risks deriving from soil pollution.

  15. Vibration analysis of orthotropic circular and elliptical nano-plates embedded in elastic medium based on nonlocal Mindlin plate theory and using Galerkin method

    Energy Technology Data Exchange (ETDEWEB)

    Anjomshoa, Amin; Tahani, Masoud [Ferdowsi University, Mashhad (Iran, Islamic Republic of)

    2016-06-15

    In the present study a continuum model based on the nonlocal elasticity theory is developed for free vibration analysis of embedded ortho tropic thick circular and elliptical nano-plates rested on an elastic foundation. The elastic foundation is considered to behave like a Pasternak type of foundations. Governing equations for vibrating nano-plate are derived according to the Mindlin plate theory in which the effects of shear deformations of nano-plate are also included. The Galerkin method is then employed to obtain the size dependent natural frequencies of nano-plate. The solution procedure considers the entire nano-plate as a single super-continuum element. Effect of nonlocal parameter, lengths of nano-plate, aspect ratio, mode number, material properties, thickness and foundation on circular frequencies are investigated. It is seen that the nonlocal frequencies of the nano-plate are smaller in comparison to those from the classical theory and this is more pronounced for small lengths and higher vibration modes. It is also found that as the aspect ratio increases or the nanoplate becomes more elliptical, the small scale effect on natural frequencies increases. Further, it is observed that the elastic foundation decreases the influence of nonlocal parameter on the results. Since the effect of shear deformations plays an important role in vibration analysis and design of nano-plates, by predicting smaller values for fundamental frequencies, the study of these nano-structures using thick plate theories such as Mindlin plate theory is essential.

  16. Source location in plates based on the multiple sensors array method and wavelet analysis

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Hong Jun; Shin, Tae Jin; Lee, Sang Kwon [Inha University, Incheon (Korea, Republic of)

    2014-01-15

    A new method for impact source localization in a plate is proposed based on the multiple signal classification (MUSIC) and wavelet analysis. For source localization, the direction of arrival of the wave caused by an impact on a plate and the distance between impact position and sensor should be estimated. The direction of arrival can be estimated accurately using MUSIC method. The distance can be obtained by using the time delay of arrival and the group velocity of the Lamb wave in a plate. Time delay is experimentally estimated using the continuous wavelet transform for the wave. The elasto dynamic theory is used for the group velocity estimation.

  17. Free Vibration Analysis of Sectorial Plates Using the Triangular Differential Quadrature Method

    Institute of Scientific and Technical Information of China (English)

    李欣; 钟宏志; 何玉红

    2004-01-01

    The triangular differential quadrature method was used to analyze the free vibrations of moderately thick sectorial plates. A triangular serendipity transformation was introduced to map the sectorial domain onto a unit isosceles right triangle. The first six non-dimensional frequencies of the sectorial plates were obtained for various combinations of clamped and simply supported boundary conditions. For sectorial plates with simply supported radial edges, the present results agree well with the available exact solutions and finite element solutions, demonstrating the effectiveness of the method.

  18. Consideration of Uninterrupted Conditions in Solving the Tasks of Plate Bending by the Finite - Element Method

    Directory of Open Access Journals (Sweden)

    Azaryan N. A.

    2007-06-01

    Full Text Available It is suggested a modification of tetragonal finite - element method, where the tasks of plate bending with taking into accountancy uninterrupted normal efforts or displacements are reduced to quadratic programming ones.

  19. Plate screening methods for the detection of polysaccharase-producing microorganisms

    NARCIS (Netherlands)

    Ruijssenaars, H.J.; Hartmans, S.

    2000-01-01

    Polysaccharide-degrading enzymes (polysaccharases) are widely applied in industry. One of the sources of these enzymes are polysaccharide-degrading microorganisms. To obtain such microorganisms from enrichment cultures, strain collections or gene libraries, efficient plate screening methods are requ

  20. Isolation method (direct plating or enrichment) does not affect antimicrobial susceptibility of Campylobacter from chicken carcasses

    Science.gov (United States)

    To determine if Campylobacter isolation method influenced antimicrobial susceptibility results, the minimum inhibitory concentrations (MIC) of nine antimicrobials were compared for 291 pairs of Campylobacter isolates recovered from chicken carcass rinse samples using direct plating and an enrichment...

  1. A multiresolution finite element method based on a new locking-free rectangular Mindlin plate element

    CERN Document Server

    Xia, Yi-Ming

    2015-01-01

    A locking-free rectangular Mindlin plate element with a new multi-resolution analysis (MRA) is proposed and a multireolution finite element method is hence presented. The MRA framework is formulated out of a mutually nesting displacement subspace sequence. The MRA endows the proposed element with the resolution level (RL) to adjust the element node number, thus modulating structural analysis accuracy accordingly. As a result, the traditional 4-node rectangular Mindlin plate element and method is a mono-resolution one and also a special case of the proposed element and method. The meshing for the monoresolution plate element model is based on the empiricism while the RL adjusting for the multiresolution is laid on the rigorous mathematical basis. The accuracy of a structural analysis is actually determined by the RL, not by the mesh. The rational MRA enables the implementation of the multiresolution Mindlin plate element method to be more rational and efficient than that of the conventional monoresolution or o...

  2. Implementation Methods of Computer Aided Design-Drawing and Drawing Management for Plate Cutting-Machine

    Institute of Scientific and Technical Information of China (English)

    DONG Yu-de; ZHAO Han; TAN Jian-rong

    2002-01-01

    The implementation methods of computer aided design,drawing and drawing management for plate cuttingmachine are discussed. The system structure for plate cutting- machine design is put forward firstly, then some key technologies and their implementation methods are introduced, which include the structure management of graphics, the unification of graph and design calculation, information share of part, assemble and drawing management system, and movement simulation of key components.

  3. Orthotopic Autologous Chondrocyte Grafting as a Method of Treatment of Growth Plate Damage in Rabbits.

    Science.gov (United States)

    Tomaszewski, Ryszard; Wiktor, Łukasz; Gap, Artur

    2016-10-28

    With the continuous advances in the therapy of joint cartilage injury, some of those classification systems are also being used for evaluating the quality of regenerating cartilage. Histo lo gi cal assessment of joint cartilage is a very important component in the staging of osteoarthritis and tracing therapeutic outcomes. We performed a histological assessment of regenerating growth plate in a group of New Zealand white rabbits as a component of autologous chondrocyte therapy for growth plate damage. We studied a group of 14 five-week-old in-bred white rabbits. We used a tre phine needle to harvest growth plate from the medial fourth of tibial width. The mean duration of the procedure was 25 minutes (range: 12-37 minutes). We conducted a total of 25 growth plate harvesting procedures. In 21 cases, we placed a drainage tube at the site of the defect for 22 days. After removing the tube, we introduced a cartilago-fibrinous construct containing cultured autologous chondrocytes into 14 defects, while 4 defects were left intact. Three growth plates represented non-intervention controls. Our analysis showed satisfactory graft morphology and integration; absence of inflammatory res ponse and fair restitution of growth plate architecture. 1. Growth plate damage can lead to the development of an angular deformity as a result of im paired longitudinal bone growth; 2. Autologous chondrocyte grafting is a good method of treatment for growth plate damage; 3. A weakness of autologous chondrocyte grafting is the relatively long time of chondrocyte culturing.

  4. An Effective Method for Free Vibration of Plate on Elastic Half Space

    Institute of Scientific and Technical Information of China (English)

    Wang Yuanhan; Gong Wenhui

    2004-01-01

    The vibration analysis of a plate on an elastic foundation is an important problem in engineering. It is the interaction of a plate with the three-dimensional half space and the plate is usually loaded from both the upper and lower surfaces. The contact pressure from the soil can not be predefined. According to Lamb's solution for a single oscillating force acting on a point on the surface of an elastic half space, and the relevant approximation formulae, a relation between the local pressure and the deflection of the plate has been proposed. Based on this analysis, the reaction of the soil can be represented as the deformation of the plate. Therefore, the plate can be separated from the soil and only needs to be divided by a number of elements in the analysis. The following procedure is the same as the standard finite element method. This is a semi-analytical and semi-numerical method. It has been applied to the dynamic analysis of circular or rectangular plates on the elastic half space, at low or high frequency vibration, and on rigid, soft or flexible foundations. The results show that this method is versatile and highly accurate.

  5. Echinocandin susceptibility testing of Candida species: comparison of EUCAST EDef 7.1, CLSI M27-A3, Etest, disk diffusion, and agar dilution methods with RPMI and isosensitest media.

    Science.gov (United States)

    Arendrup, Maiken Cavling; Garcia-Effron, Guillermo; Lass-Flörl, Cornelia; Lopez, Alicia Gomez; Rodriguez-Tudela, Juan-Luis; Cuenca-Estrella, Manuel; Perlin, David S

    2010-01-01

    This study compared nine susceptibility testing methods and 12 endpoints for anidulafungin, caspofungin, and micafungin with the same collection of blinded FKS hot spot mutant (n = 29) and wild-type isolates (n = 94). The susceptibility tests included EUCAST Edef 7.1, agar dilution, Etest, and disk diffusion with RPMI-1640 plus 2% glucose (2G) and IsoSensitest-2G media and CLSI M27A-3. Microdilution plates were read after 24 and 48 h. The following test parameters were evaluated: fks hot spot mutants overlapping the wild-type distribution, distance between the two populations, number of very major errors (VMEs; fks mutants misclassified as susceptible), and major errors (MEs; wild-type isolates classified as resistant) using a wild-type-upper-limit value (WT-UL) (two twofold-dilutions higher than the MIC(50)) as the susceptibility breakpoint. The methods with the lowest number of errors (given as VMEs/MEs) across the three echinocandins were CLSI (12%/1%), agar dilution with RPMI-2G medium (14%/0%), and Etest with RPMI-2G medium (8%/3%). The fewest errors overall were observed for anidulafungin (4%/1% for EUCAST, 4%/3% for CLSI, and 3%/9% for Etest with RPMI-2G). For micafungin, VME rates of 10 to 71% were observed. For caspofungin, agar dilution with either medium was superior (VMEs/MEs of 0%/1%), while CLSI, EUCAST with IsoSensitest-2G medium, and Etest were less optimal (VMEs of 7%, 10%, and 10%, respectively). Applying the CLSI breakpoint (S CLSI results, 89.2% fks hot spot mutants were classified as anidulafungin susceptible, 60.7% as caspofungin susceptible, and 92.9% as micafungin susceptible. In conclusion, no test was perfect, but anidulafungin susceptibility testing using the WT-UL to define susceptibility reliably identified fks hot spot mutants.

  6. Echinocandin Susceptibility Testing of Candida Species: Comparison of EUCAST EDef 7.1, CLSI M27-A3, Etest, Disk Diffusion, and Agar Dilution Methods with RPMI and IsoSensitest Media▿

    Science.gov (United States)

    Arendrup, Maiken Cavling; Garcia-Effron, Guillermo; Lass-Flörl, Cornelia; Lopez, Alicia Gomez; Rodriguez-Tudela, Juan-Luis; Cuenca-Estrella, Manuel; Perlin, David S.

    2010-01-01

    This study compared nine susceptibility testing methods and 12 endpoints for anidulafungin, caspofungin, and micafungin with the same collection of blinded FKS hot spot mutant (n = 29) and wild-type isolates (n = 94). The susceptibility tests included EUCAST Edef 7.1, agar dilution, Etest, and disk diffusion with RPMI-1640 plus 2% glucose (2G) and IsoSensitest-2G media and CLSI M27A-3. Microdilution plates were read after 24 and 48 h. The following test parameters were evaluated: fks hot spot mutants overlapping the wild-type distribution, distance between the two populations, number of very major errors (VMEs; fks mutants misclassified as susceptible), and major errors (MEs; wild-type isolates classified as resistant) using a wild-type-upper-limit value (WT-UL) (two twofold-dilutions higher than the MIC50) as the susceptibility breakpoint. The methods with the lowest number of errors (given as VMEs/MEs) across the three echinocandins were CLSI (12%/1%), agar dilution with RPMI-2G medium (14%/0%), and Etest with RPMI-2G medium (8%/3%). The fewest errors overall were observed for anidulafungin (4%/1% for EUCAST, 4%/3% for CLSI, and 3%/9% for Etest with RPMI-2G). For micafungin, VME rates of 10 to 71% were observed. For caspofungin, agar dilution with either medium was superior (VMEs/MEs of 0%/1%), while CLSI, EUCAST with IsoSensitest-2G medium, and Etest were less optimal (VMEs of 7%, 10%, and 10%, respectively). Applying the CLSI breakpoint (S ≤ 2 μg/ml) for CLSI results, 89.2% fks hot spot mutants were classified as anidulafungin susceptible, 60.7% as caspofungin susceptible, and 92.9% as micafungin susceptible. In conclusion, no test was perfect, but anidulafungin susceptibility testing using the WT-UL to define susceptibility reliably identified fks hot spot mutants. PMID:19884370

  7. In vitro susceptibility of filamentous fungi to copper nanoparticles assessed by rapid XTT colorimetry and agar dilution method.

    Science.gov (United States)

    Ghasemian, E; Naghoni, A; Tabaraie, B; Tabaraie, T

    2012-12-01

    Metal nanoparticles and their uses in various aspects have recently drawn a great deal of attention. One of the major applications is that it can be used as an antimicrobial agent. They can be considered in approaches targeted to decrease the harms caused by microorganisms, specifically fungi, threatening the medical and industrial areas. The aim of this study was to investigate the antifungal activity of synthesized copper nanoparticles (CuNPs) against four filamentous fungi including Alternaria alternata, Aspergillus flavus, Fusarium solani, and Penicillium chrysogenum. Zerovalent copper nanoparticles of mean size 8nm were synthesized by inert gas condensation (IGC) method. The antifungal activity of these synthesized copper nanoparticles was measured against selected fungi by using two different techniques including agar dilution method and XTT reduction assay. The minimal inhibitory concentrations (MICs) for copper nanoparticles by agar dilution method were less or equal to 40mg/L for P. chrysogenum, less or equal to 60mg/L for A. alternata, less or equal to 60mg/L for F. solani, and less or equal to 80mg/L for A. flavus. And also MICs obtained by XTT reduction assay ranged from 40 to 80mg/L. Our data demonstrated that the copper nanoparticles inhibited fungal growth, but the fungal sensitivity to copper nanoparticles varies depending on the fungal species. Therefore, it is advisable that the minimal inhibitory concentrations (MICs) be examined before using these compounds. It is hoped that, in future, copper nanoparticles could replace some antifungal agents, making them applicable to many different medical devices and antimicrobial control system. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

  8. Optical and Magnetic Properties of Fe-Doped GaN Diluted Magnetic Semiconductors Prepared by MOCVD Method

    Institute of Scientific and Technical Information of China (English)

    TAG Zhi-Kuo; ZHANG Rong; CUI Xu-Gao; XIU Xiang-Qian; ZHANG Guo-Yu; XIE Zi-Li; GU Shu-Lin; SHI Yi; ZHENG You-Dou

    2008-01-01

    @@ Fe-doped GaN thin films are grown on c-sapphires by metal organic chemical vapour deposition method (MOCVD).Crystalline quality and phase purity are characterized by x-ray diffraction and Raman scattering measurements.There are no detectable second phases formed during growth and no significant degradation in crystalline quality as Fe ions are doped. Fe-related optical transitions are observed in photoluminescence spectra. Magnetic measurements reveal that the films show room-temperature ferromagnetic behaviour. The ferromagnetism may originate from carrier-mediated Fe-doped CaN diluted magnetic semiconductors or nanoscale iron dusters and Fe-N compounds which we have not detected.

  9. Preparation of Nano-sized Zirconium Carbide Powders through a Novel Active Dilution Self-propagating High Temperature Synthesis Method

    Institute of Scientific and Technical Information of China (English)

    DA Aoyun; LONG Fei; WANG Jilin; XING Weihong; WANG Yang; ZHANG Fan; WANG Weimin; FU Zhengyi

    2015-01-01

    High quality nano-sized zirconium carbide (ZrC) powders were successfully fabricated via a developed chemical active dilution self-propagating high-temperature synthesis (SHS) method assisted by ball milling pretreatment process using traditional cheap zirconium dioxide powder (ZrO2), magnesium powder (Mg) and sucrose (C12H22O11) as raw materials. FSEM, TEM, HRTEM, SAED, XRD, FTIR and Raman, ICP-AES, laser particle size analyzer, oxygen and nitrogen analyzer, carbon/sulfur determinator and TG-DSC were employed for the characterization of the morphology, structure, chemical composition and thermal stability of the as-synthesized ZrC samples. The as-synthesized samples demonstrated high purity, low oxygen content and evenly distributed ZrC nano-powders with an average particle size of 50nm. In addition, the effects of endothermic rate and the possible chemical reaction mechanism were also discussed.

  10. DUAL RECIPROCITY BOUNDARY ELEMENT METHOD FOR FLEXURAL WAVES IN THIN PLATE WITH CUTOUT

    Institute of Scientific and Technical Information of China (English)

    GAO Suo-wen; WANG Yue-sheng; ZHANG Zi-mao; MA Xing-rui

    2005-01-01

    The theoretical analysis and numerical calculation of scattering of elastic waves and dynamic stress concentrations in the thin plate with the cutout was studied using dual reciprocity boundary element method (DRM). Based on the work equivalent law, the dual reciprocity boundary integral equations for flexural waves in the thin plate were established using static fundamental solution. As illustration, numerical results for the dynamic stress concentration factors in the thin plate with a circular hole are given.The results obtained demonstrate good agreement with other reported results and show high accuracy.

  11. Natural frequencies of cracked functionally graded material plates by the extended finite element method

    CERN Document Server

    Natarajan, S; Bordas, S; Rabczuk, T; Kerfriden, P

    2011-01-01

    In this paper, the linear free flexural vibration of cracked functionally graded material plates is studied using the extended finite element method. A 4-noded quadrilateral plate bending element based on field and edge consistency requirement with 20 degrees of freedom per element is used for this study. The natural frequencies and mode shapes of simply supported and clamped square and rectangular plates are computed as a function of gradient index, crack length, crack orientation and crack location. The effect of thickness and influence of multiple cracks is also studied.

  12. Vibration and Buckling Analysis of Moderately Thick Plates using Natural Element Method

    Directory of Open Access Journals (Sweden)

    Mohammad Etemadi

    2015-07-01

    Full Text Available Using natural element method (NEM, the buckling and the free vibration behaviors of moderate thick plates is studied here. The basis of NEM is natural neighbors and Voronoi cells concepts. The shape functions of nodes located in the domain is equal to the proportion of common natural neighbors area divided by area that related by each Voronoi cells. First step in analyzing the moderate thick plates is identification boundaries. This is done by nodes scattering on problem domain. Mindlin/Reissner theory is used to express the equations of moderate thick plate. First and second order shape functions obtained from natural element method are used to discretize differential equations. Using numerical integration on whole discrete equations of domain, stiffness, geometry and mass matrices of plate are obtained. Buckling loads and vibration modes are expressed by substituting these matrices in plate equations of motions. Arbitrary shapes of plate are selected for solution. Comparing the results of the current approach with those obtained by other numerical analytical methods, it is shown that natural element method can solve problems with complex areas accurately.

  13. 盐度对稀释平板法研究红树林区土壤微生物数量的影响%Effect of salinity on microbial densities of soil in the dilution plate technique applied in mangrove areas

    Institute of Scientific and Technical Information of China (English)

    张瑜斌; 林鹏; 魏小勇; 庄铁诚

    2008-01-01

    When the soil microbial densities are determined in mangroves and corresponding mudflat at the same tidal level by the dilution plate method, the agar media and dilution water are generally made up of aged seawater in most cases, and effects of salinity in agar media and dilution water on the enumeration of microbes is seldom taken into consideration. The effects of salinity on soil microbial counting from the samples in mangrove areas in Jiulongjiang Estuary of Fujian, and Futian Mangrove Nature Reserve of Shenzhen, China, were tested by dilution plate technique. The results showed that the soil microbial densities in mangroves and mudflat were significantly influenced by the salinity of dilution water and agar media. For the bacteria, the seawater served as sterilized dilution water was significantly (P<0.05) more benefic to the enumeration on the plates than the freshwater, but in reverse for the actinomycetes and fungi. The increasing salinity of media within 35 significantly decreased microbial colonies on the plates, especially for the actinomycetes, in spite of the fact that the effect of salinity of media on fungal numbers was not indefinite. The bacterial colonies were more abundant on the agar plates with low salinity than with high salinity or without any NaCl. It was proposed that some methodological improvements were needed when the dilution plate technique was applied to microbial counting in the samples of mangrove forest and mudflat at the same tidal level in inter-tidal zone. The sterilized dilution water should be prepared with seawater for the bacteria, but with freshwater or low saline water for the actinomycetes and fungi. The salinity of agar media should be low for the microbial isolation and enumeration of soil samples from the mangrove areas including mudflats.%在使用稀释平板法分离潮间带红树林及其对照光滩土壤微生物以及计数时,多数情况下使用陈海水制作培养基和稀释水,很少考虑培养基和

  14. Determination of niobium in rocks by an isotope dilution spectrophotometric method

    Science.gov (United States)

    Greenland, L.P.; Campbell, E.Y.

    1970-01-01

    Rocks and minerals are fused with sodium peroxide in the presence of carrierfree 95Nb. The fusion cake is leached with water and the precipitate dissolved in hydrofluoric-sulfuric acid mixture. Niobium is extracted into methyl isobutyl ketone and further purified by ion exchange. The amount of niobium is determined spectrophotometrically with 4-(2-pyridylazo)-resorcinol, and the chemical yield of the separations determined by counting 95Nb. This procedure is faster and less sensitive to interferences than previously proposed methods for determining niobium in rocks.The high purity of the separated niobium makes the method applicable to nearly all matrices. ?? 1970.

  15. DIFFERENTIAL QUADRATURE METHOD FOR BENDING OF ORTHOTROPIC PLATES WITH FINITE DEFORMATION AND TRANSVERSE SHEAR EFFECTS

    Institute of Scientific and Technical Information of China (English)

    李晶晶; 程昌钧

    2004-01-01

    Based on the Reddy' s theory of plates with the effect of higher-order shear deformations, the governing equations for bending of orthotropic plates with finite deformations were established. The differential quadrature ( DQ ) method of nonlinear analysis to the problem was presented. New DQ approach, presented by Wang and Bert (DQWB), is extended to handle the multiple boundary conditions of plates. The techniques were also further extended to simplify nonlinear computations. The numerical convergence and comparison of solutions were studied. The results show that the DQ method presented is very reliable and valid. Moreover, the influences of geometric and material parameters as well as the transverse shear deformations on nonlinear bending were investigated.Numerical results show the influence of the shear deformation on the static bending of orthotropic moderately thick plate is significant.

  16. A simplified dilution method for detection of Campylobacter in broiler ceca

    Science.gov (United States)

    Campylobacter species, a leading foodborne pathogen, is linked to poultry. Development of intervention strategies depends on the ability to rapidly and consistently recover and estimate the number of bacteria present. The objective of this experim ent was to validate a semi-quantitative method for d...

  17. New method and uncertainty estimation for plate dimensions and surface measurements

    Science.gov (United States)

    Ali, Salah H. R.; Buajarern, Jariya

    2014-03-01

    Dimensional and surface quality for tile plate manufacturing control is facing difficult engineering challenges. One of these challenges being that plates in large-scale mass production contain geometrically uneven surfaces. There is a traditional measurement method used to assess the tile plate dimensions and surface quality based on standard specifications: ISO-10545-2: 1995, EOS-3168-2: 2007 and TIS 2398-2:2008. A new measurement method of the dimensions and surface quality for ceramic oblong large-scale tile plate has been developed compared to the traditional method. The strategy of the proposed method is based on CMM straightness measurement strategy instead of the centre point in the traditional method. Expanded uncertainties budgets in the measurements of each method have been estimated in detail. The capability of accurate estimations of real actual results of centre of curvature (CC), centre of edge (CE), warpage (W) and edge crack defects parameters has been achieved according to standards. Moreover, the obtained results showed not only a more accurate method but also improved the quality of tile plate products significantly.

  18. New Measurement Method and Uncertainty Estimation for Plate Dimensions and Surface Quality

    Directory of Open Access Journals (Sweden)

    Salah H. R. Ali

    2013-01-01

    Full Text Available Dimensional and surface quality for plate production control is facing difficult engineering challenges. One of these challenges is that plates in large-scale mass production contain geometric uneven surfaces. There is a traditional measurement method used to assess the tile plate dimensions and surface quality based on standard specifications: ISO-10545-2: 1995, EOS-3168-2: 2007, and TIS 2398-2: 2008. A proposed measurement method of the dimensions and surface quality for ceramic oblong large-scale tile plate has been developed compared to the traditional method. The strategy of new method is based on CMM straightness measurement strategy instead of the centre point in the traditional method. Expanded uncertainties budgets in the measurements of each method have been estimated in detail. The capability of accurate estimations of real actual results for centre of curvature (CC, centre of edge (CE, warpage (W, and edge crack defects parameters has been achieved according to standards. Moreover, the obtained results not only showed better accurate new method but also improved the quality of plate products significantly.

  19. Numerical Methods for Plate Forming by Line Heating

    DEFF Research Database (Denmark)

    Clausen, Henrik Bisgaard

    2000-01-01

    Few researchers have addressed so far the topic Line Heating in the search for better control of the process. Various methods to help understanding the mechanics have been used, including beam analysis approximation, equivalent force calculation and three-dimensional finite element analysis. I...... consider here finite element methods to model the behaviour and to predict the heating paths....

  20. Topology Optimization of Constrained Layer Damping on Plates Using Method of Moving Asymptote (MMA Approach

    Directory of Open Access Journals (Sweden)

    Zheng Ling

    2011-01-01

    Full Text Available Damping treatments have been extensively used as a powerful means to damp out structural resonant vibrations. Usually, damping materials are fully covered on the surface of plates. The drawbacks of this conventional treatment are also obvious due to an added mass and excess material consumption. Therefore, it is not always economical and effective from an optimization design view. In this paper, a topology optimization approach is presented to maximize the modal damping ratio of the plate with constrained layer damping treatment. The governing equation of motion of the plate is derived on the basis of energy approach. A finite element model to describe dynamic performances of the plate is developed and used along with an optimization algorithm in order to determine the optimal topologies of constrained layer damping layout on the plate. The damping of visco-elastic layer is modeled by the complex modulus formula. Considering the vibration and energy dissipation mode of the plate with constrained layer damping treatment, damping material density and volume factor are considered as design variable and constraint respectively. Meantime, the modal damping ratio of the plate is assigned as the objective function in the topology optimization approach. The sensitivity of modal damping ratio to design variable is further derived and Method of Moving Asymptote (MMA is adopted to search the optimized topologies of constrained layer damping layout on the plate. Numerical examples are used to demonstrate the effectiveness of the proposed topology optimization approach. The results show that vibration energy dissipation of the plates can be enhanced by the optimal constrained layer damping layout. This optimal technology can be further extended to vibration attenuation of sandwich cylindrical shells which constitute the major building block of many critical structures such as cabins of aircrafts, hulls of submarines and bodies of rockets and missiles as an

  1. DYNAMIC RESPONSE OF PLATES DUE TO MOVING VEHICLES USING FINITE STRIP METHOD

    Institute of Scientific and Technical Information of China (English)

    程远胜; 张佑啟; 区达光

    2002-01-01

    Dynamic response of beam-like structures to moving vehicles has been extensive-ly studied. However, the study on dynamic response of plates to moving vehicles has so farreceived but scant attention. A plate-vehicle strip for simulating the interaction between arectangular plate and moving vehicles was described. For the portion of strips that are in di-rect contact with the moving vehicles, the plate-vehicle strips were employed. Conventionalplate finite strips were used to model the portion of strips that are not directly under the ac-tion of moving vehicles. In the analysis, each moving vehicle is idealized as a one-foot dy-namic system with the unsprung mass and sprund mass interconnected by a spring and adashpot. The numerical results obtained from the proposed method agree well with availableresults.

  2. Electrochemical Device Comprising Composite Bipolar Plate and Method of Using the Same

    Science.gov (United States)

    Mittelsteadt, Cortney K. (Inventor); Braff, William A. (Inventor)

    2017-01-01

    An electrochemical device and methods of using the same. In one embodiment, the electrochemical device may be used as a fuel cell and/or as an electrolyzer and includes a membrane electrode assembly (MEA), an anodic gas diffusion medium in contact with the anode of the MEA, a cathodic gas diffusion medium in contact with the cathode, a first bipolar plate in contact with the anodic gas diffusion medium, and a second bipolar plate in contact with the cathodic gas diffusion medium. Each of the bipolar plates includes an electrically-conductive, chemically-inert, non-porous, liquid-permeable, substantially gas-impermeable membrane in contact with its respective gas diffusion medium, as well as a fluid chamber and a non-porous an electrically-conductive plate.

  3. Electrochemical Device Comprising Composite Bipolar Plate and Method of Using the Same

    Science.gov (United States)

    Mittelsteadt, Cortney K. (Inventor); Braff, William A. (Inventor)

    2013-01-01

    An electrochemical device and methods of using the same. In one embodiment, the electrochemical device may be used as a fuel cell and/or as an electrolyzer and includes a membrane electrode assembly (MEA), an anodic gas diffusion medium in contact with the anode of the MEA, a cathodic gas diffusion medium in contact with the cathode, a first bipolar plate in contact with the anodic gas diffusion medium, and a second bipolar plate in contact with the cathodic gas diffusion medium. Each of the bipolar plates includes an electrically-conductive, chemically-inert, non-porous, liquid-permeable, substantially gas-impermeable membrane in contact with its respective gas diffusion medium, as well as a fluid chamber and a non-porous an electrically-conductive plate.

  4. The evaluation of susceptibility of clinical and environmental Nontuberculosis mycobacterium isolated from Isfahan to Ciprofloxacin by Agar dilution method

    Directory of Open Access Journals (Sweden)

    Tooba Radaei

    2013-01-01

    Full Text Available Introduction: Ciprofloxacin is a fluoroquinolone antibiotic which is active against mycobacteria and functions by inhibiting DNA gyrase and topoisomerase IV enzymes. Resistance to ciprofloxacin and other fluoroquinolones may evolve rapidly, even during a course of treatment. Nowadays, mycobacteria exhibit resistance worldwide and usage of the fluoroquinolones, particularly in nontuberculous mycobacteria disease, has complicated the related treatments. Materials and methods: A total of 39 clinical and environmental isolates of NTM from microbial collections of Isfahan Microbiology Department and Tuberculosis center were obtained. The isolates were investigated by primary conventional methods consisting of colony characteristics, pigmentation, growth temperature, rate of growth and Ziehl–Neelsen staining. The susceptibility of isolates to the concentrations of 1, 2 and 4 µg/ml of ciprofloxacin was determined by agar dilution method according to the CLSI guideline.Results: Thirty nine isolates were identified by phenotypic tests. The frequency of isolates was as follow: M. fortuitum; 25 cases, M. gordonae; 10 cases, M. smegmatis; 1 case, M.‏conceptionense; 1 case and M. abscessus; 2 cases. All isolates except Mycobacterium abscessus were sensitive to all three concentrations of 1, 2 and 4 µg/ml ciprofloxacin.Discussion and conclusion: Due to the sensitivity of environmental nontuberculous mycobacteria isolates (except M. abscessus and clinical isolates including M. fortuitum and M.‏gordonae to ciprofloxacin, this antibiotic could be regarded as the original drug in the treatment of these infections.

  5. Online determination of copper in aluminum alloy by microchip solvent extraction using isotope dilution ICP-MS method.

    Science.gov (United States)

    Kagawa, Tsuyoshi; Ohno, Masashi; Seki, Tatsuya; Chikama, Katsumi

    2009-09-15

    Isotope dilution mass spectroscopy (IDMS)/ICP-MS combined with microchip solvent extraction was successfully applied for the online determination of copper in an aluminum alloy. The microchip solvent extraction was developed for the separation of Cu from major element, and optimal pH range was wider than that of the batchwise extraction method. The dimensions of the microchip were 30 mm x 70 mm and that of micro-channel on the microchip was 180 microm wide and 40 microm deep. The copper complex with 8-hydroxyquinoline was extracted into o-xylene at pH 5.5 and back extracted with 0.1 mol l(-1) nitric acid at flow rate of 20 microl min(-1). The total extraction efficiency (water/organic solvent/nitric acid) was around 40%. IDMS/ICP-MS was coupled with solvent extraction for precise determination of Cu. The extraction and back-extraction on the microchip took about 1s and the total measurement time for the IDMS/ICP-MS was about 40s/sample. The blank value of this method was 0.1 ng g(-1). The proposed method was used for the determination of Cu in Al standard materials (JSAC 0121-C, The Japan Society for Analytical Chemistry and 7074 Al alloy, Nippon Light Metal Co. Ltd.). The obtained analytical results are in good agreement with the certified values.

  6. An Agar-Based Method for Plating Marine Protozoan Parasites of the Genus Perkinsus.

    Directory of Open Access Journals (Sweden)

    Emma R Cold

    Full Text Available The genus Perkinsus includes protozoan parasites of mollusks responsible for losses in the aquaculture industry and hampering the recovery of natural shellfish beds worldwide, and they are a key taxon for understanding intracellular parasitism adaptations. The ability to propagate the parasite in liquid media, in the absence of the host, has been crucial for improving understanding of its biology; however, alternative techniques to grow the parasite are needed to explore other basic aspects of the Perkinsus spp. biology. We optimized a DME: Ham's F12-5% FBS- containing solid agar medium for plating Perkinsus marinus. This solid medium supported trophozoite propagation both by binary fission and schizogony. Colonies were visible to the naked eye 17 days after plating. We tested the suitability of this method for several applications, including the following: 1 Subcloning P. marinus isolates: single discrete P. marinus colonies were obtained from DME: Ham's F12-5% FBS- 0.75% agar plates, which could be further propagated in liquid medium; 2 Subcloning engineered Perkinsus mediterraneus MOE[MOE]: GFP by streaking cultures on plates; 3 Chemical susceptibility: Infusing the DME: Ham's F12-5% FBS- 0.75% agar plates with triclosan resulted in inhibition of the parasite propagation in a dose-dependent manner. Altogether, our plating method has the potential for becoming a key tool for investigating diverse aspects of Perkinsus spp. biology, developing new molecular tools, and for biotechnological applications.

  7. Modeling of Intermesh Schedule for Strong Heavy Plate Roller Straightener and Finite Element Method Modification

    Directory of Open Access Journals (Sweden)

    Meng Xu

    2016-01-01

    Full Text Available Regarding straightening unit as the research object, considered the different of roller spacing, a mathematical model of intermesh schedule suitable to the 2800 seven-roller strong heavy plate straightening machine was deduced by the geometric method. According to the mathematical model, the intermesh schedules of several specifications of plate were calculated, and the finite element model of straightening process was established in the finite element analysis software Abaqus. By analysing, it was found that those plates after straightening cannot meet the requirement of flatness, due to the existence of the work hardening. The bending deflection of the last straightening unit was modified and the new calculation formula of intermesh schedule was obtained. The values of the modified coefficients were determined by the finite element method. The intermesh schedules of other specifications of plate were calculated by the modified calculation formula and then verified it in Abaqus. The simulation results showed that those plates after straightening meet the requirement of flatness. So, the research results provide a theoretical basis for development of a new plate straightening machine and formulation of intermesh schedule.

  8. An Agar-Based Method for Plating Marine Protozoan Parasites of the Genus Perkinsus.

    Science.gov (United States)

    Cold, Emma R; Freyria, Nastasia J; Martínez Martínez, Joaquín; Fernández Robledo, José A

    2016-01-01

    The genus Perkinsus includes protozoan parasites of mollusks responsible for losses in the aquaculture industry and hampering the recovery of natural shellfish beds worldwide, and they are a key taxon for understanding intracellular parasitism adaptations. The ability to propagate the parasite in liquid media, in the absence of the host, has been crucial for improving understanding of its biology; however, alternative techniques to grow the parasite are needed to explore other basic aspects of the Perkinsus spp. biology. We optimized a DME: Ham's F12-5% FBS- containing solid agar medium for plating Perkinsus marinus. This solid medium supported trophozoite propagation both by binary fission and schizogony. Colonies were visible to the naked eye 17 days after plating. We tested the suitability of this method for several applications, including the following: 1) Subcloning P. marinus isolates: single discrete P. marinus colonies were obtained from DME: Ham's F12-5% FBS- 0.75% agar plates, which could be further propagated in liquid medium; 2) Subcloning engineered Perkinsus mediterraneus MOE[MOE]: GFP by streaking cultures on plates; 3) Chemical susceptibility: Infusing the DME: Ham's F12-5% FBS- 0.75% agar plates with triclosan resulted in inhibition of the parasite propagation in a dose-dependent manner. Altogether, our plating method has the potential for becoming a key tool for investigating diverse aspects of Perkinsus spp. biology, developing new molecular tools, and for biotechnological applications.

  9. Applications of a General Finite-Difference Method for Calculating Bending Deformations of Solid Plates

    Science.gov (United States)

    Walton, William C., Jr.

    1960-01-01

    This paper reports the findings of an investigation of a finite - difference method directly applicable to calculating static or simple harmonic flexures of solid plates and potentially useful in other problems of structural analysis. The method, which was proposed in doctoral thesis by John C. Houbolt, is based on linear theory and incorporates the principle of minimum potential energy. Full realization of its advantages requires use of high-speed computing equipment. After a review of Houbolt's method, results of some applications are presented and discussed. The applications consisted of calculations of the natural modes and frequencies of several uniform-thickness cantilever plates and, as a special case of interest, calculations of the modes and frequencies of the uniform free-free beam. Computed frequencies and nodal patterns for the first five or six modes of each plate are compared with existing experiments, and those for one plate are compared with another approximate theory. Beam computations are compared with exact theory. On the basis of the comparisons it is concluded that the method is accurate and general in predicting plate flexures, and additional applications are suggested. An appendix is devoted t o computing procedures which evolved in the progress of the applications and which facilitate use of the method in conjunction with high-speed computing equipment.

  10. Development of Time-Reversal Method for Impact Source Identification on Plate Structures

    Directory of Open Access Journals (Sweden)

    Chunlin Chen

    2013-01-01

    Full Text Available This paper presents a detailed study on the impact source identification of a plate structure using time-reversal (T-R method. Prior to impact monitoring, the plate is calibrated (or characterized by transfer functions at discrete locations on the plate surface. Both impact location and impact loading time-history are identified using T-R technique and associated signal processing algorithms. Numerical verification for finite-size isotropic plates under low velocity impacts is performed to demonstrate the versatility of T-R method for impact source identification. The tradeoff between accuracy of the impact location detection and calibration spacing is studied in detail. In particular, the effect of plate thickness on calibration spacing has been examined. A number of parameters selected for determining the impact location, approximated transfer functions and steps taken for reconstructing the impact loading time-history are also examined. Two types of noise with various intensities contaminated in strain response and/or transfer functions are investigated for demonstrating the stability and reliability of the T-R method. The results show that T-R method is robust against noise in impact location detection and force reconstruction in circumventing the inherent ill-conditioned inverse problem. Only transfer functions are needed to be calibrated and four sensors are requested in T-R method for impact identification.

  11. High Velocity Tensile Test for Thin Plate Specimen with One Bar Method

    Science.gov (United States)

    Itabashi, Masaaki

    In order to design thin-walled impact-resistant structure, for example, an automotive body, dynamic behavior of thin plate is essential. So far, except for laminated composite materials, high velocity tensile test of thin plate specimen did not attract impact researchers' and engineers' attention very much. In this paper, the previous thin plate specimen assembly for the one bar method was improved. The one bar method has been utilized for cylindrical specimens of various solid materials and is known as an effective high velocity tensile testing technique. Unfortunately, the previous assembly introduced a tremendous initial peak on stress-strain curves, even for aluminum alloys. With a new specimen assembly, stress-strain curves for IF (Interstitial-atom Free) steel and 7075-T6 aluminum alloy obtained by the one bar method were almost equivalent to those obtained by the tensile version of the split Hopkinson pressure bar method.

  12. A method for the routine determination of methylmercury in marine tissue by GC isotope dilution-ICP-MS.

    Science.gov (United States)

    Valdersnes, Stig; Maage, Amund; Fliegel, Daniel; Julshamn, Kåre

    2012-01-01

    Currently, there is no legal limit for methyl mercury (MeHg) in food; thus, no standardized method for the determination of MeHg in seafood exists within the European jurisdiction. In anticipation of a future legislative limit an inductively coupled plasma isotope dilution mass spectrometry (GC-ICP-ID-MS) method was developed in collaboration with the European Standardization Organization (CEN). The method comprises spiking the tissue sample with Me201Hg, followed by decomposition with tetramethylammonium hydroxide, pH adjustment and derivatization with sodium tetraethylborate, and finally organic extraction of the derivatized MeHg in a hexane phase. Subsequently, the sample is analyzed via GC-ICP-MS and the result calculated using the ID equation. The working range of the method was 0.0005-1.321 mg/kg MeHg in marine tissue, with an internal reproducibility (RSD) of 12-1%. The method was validated based on statistical measures, such as the z-scores, using the commercially available reference materials from National Institute of Standards and Technology Standard Reference Material (NIST SRM) 1566b, NIST SRM 2977 and National Research Council of Canada (NRCC) TORT 2, NRCC, DORM 3, NRCC DOLT 4, and European Reference Material (ERM) CE 464. Z-scores for all standard reference materials, except for NIST SRM 1566b, were better than 11.51. The wide range of marine tissues used during the validation ensures that the method will be applicable for measuring of MeHg in seafood matrixes of all kinds.

  13. Verification of 235U mass content in nuclear fuel plates by an absolute method

    Science.gov (United States)

    El-Gammal, W.

    2007-01-01

    Nuclear Safeguards is referred to a verification System by which a State can control all nuclear materials (NM) and nuclear activities under its authority. An effective and efficient Safeguards System must include a system of measurements with capabilities sufficient to verify such NM. Measurements of NM using absolute methods could eliminate the dependency on NM Standards, which are necessary for other relative or semi-absolute methods. In this work, an absolute method has been investigated to verify the 235U mass content in nuclear fuel plates of Material Testing Reactor (MTR) type. The most intense gamma-ray signature at 185.7 keV emitted after α-decay of the 235U nuclei was employed in the method. The measuring system (an HPGe-spectrometer) was mathematically calibrated for efficiency using the general Monte Carlo transport code MCNP-4B. The calibration results and the measured net count rate were used to estimate the 235U mass content in fuel plates at different detector-to-fuel plate distances. Two sets of fuel plates, containing natural and low enriched uranium, were measured at the Fuel Fabrication Facility. Average accuracies for the estimated 235U masses of about 2.62% and 0.3% are obtained for the fuel plates containing natural and low enriched uranium; respectively, with a precision of about 3%.

  14. Vibration of circular plate with multiple eccentric circular perforations by the Rayleigh-Ritz method

    Energy Technology Data Exchange (ETDEWEB)

    Saeedi, Khodabakhsh; Bhat, Rama B.; Stiharu, Ion [Concordia University, Montreal (Canada); Leo, Alfin [2Parker Filtration Canada, Laval (Canada)

    2012-05-15

    The free vibration of a circular plate with multiple perforations is analyzed by using the Rayleigh-Ritz method. Admissible functions are assumed to be separable functions of radial and tangential coordinates. Trigonometric functions are assumed in the circumferential direction. The radial shape functions are the boundary characteristic orthogonal polynomials generated following the Gram-Schmidt recurrence scheme. The assumed functions are used to estimate the kinetic and the potential energies of the plate depending on the number and the position of the perforations. The eigenvalues, representing the dimensionless natural frequencies, are compared with the results obtained using Bessel functions, where the exact solution is available. Moreover, the eigenvectors, which are the unknown coefficients of the Rayleigh-Ritz method, are used to present the mode shapes of the plate. To validate the analytical results of the plates with multiple perforations, experimental investigations are also performed. Two unique case studies that are not addressed in the existing literature are considered. The results of the Rayleigh-Ritz method are found to be in good agreement with those from the experiments. Although the method presented can be employed in the vibration analysis of plates with different boundary conditions and shapes of the perforations, circular perforations that are free on the edges are studied in this paper. The results are presented in terms of dimensionless frequencies and mode shapes.

  15. Application of isotope dilution method for measuring bioavailability of organic contaminants sorbed to dissolved organic matter (DOM)

    Energy Technology Data Exchange (ETDEWEB)

    Delgado-Moreno, Laura, E-mail: laura.delgado@eez.csic.es; Wu, Laosheng; Gan, Jay

    2015-08-15

    Natural waters such as surface water and sediment porewater invariably contain dissolved organic matter (DOM). Association of strongly hydrophobic contaminants (HOCs) with DOM leads to decreased toxicity and bioavailability, but bioavailability of DOM-sorbed HOCs is difficult to measure. Current methods to estimate bioavailability of HOCs in water are based on only the freely dissolved concentration (C{sub free}). The ignorance of the exchangeable fraction of HOCs sorbed on DOM may result in an underestimation of the toxicity potential of HOCs to aquatic organisms. Here we explore the applicability of an isotope dilution method (IDM) to measuring the desorption fraction of DOM-sorbed pyrene and bifenthrin and determining their exchangeable pool (E) as an approximation of bioavailability. E values, expressed as percentage of the total concentration, ranged between 0.80 and 0.92% for pyrene and 0.74 and 0.85% for bifenthrin, depending primarily on the amount of chemical in the freely dissolved form. However, between 34 and 78% of the DOM-sorbed pyrene was exchangeable. This fraction ranged between 23% and 82% for bifenthrin. The ability of IDM to predict bioavailability was further shown from a significant relationship (r{sup 2} > 0.72, P < 0.0001) between E and bioaccumulation into Daphnia magna. Therefore, IDM may be used to improve the bioavailability measurement and risk assessment of HOCs in aquatic systems.

  16. Non-invasive method of field imaging in parallel plate waveguides

    DEFF Research Database (Denmark)

    Iwaszczuk, Krzysztof; Andryieuski, Andrei; Lavrinenko, Andrei

    2011-01-01

    We present a new non-invasive air-photonic-based method of terahertz (THz) field imaging inside a parallel plate waveguide. The method is based on THz field-enhanced second harmonic generation of the fundamental laser beam in an external electric field. We also demonstrate the direct measurements...

  17. C1-continuous Virtual Element Method for Poisson-Kirchhoff plate problem

    Energy Technology Data Exchange (ETDEWEB)

    Gyrya, Vitaliy [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Mourad, Hashem Mohamed [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-09-20

    We present a family of C1-continuous high-order Virtual Element Methods for Poisson-Kirchho plate bending problem. The convergence of the methods is tested on a variety of meshes including rectangular, quadrilateral, and meshes obtained by edge removal (i.e. highly irregular meshes). The convergence rates are presented for all of these tests.

  18. A force plate based method for the calibration of force/torque sensors

    NARCIS (Netherlands)

    Faber, Gert S.; Chang, Chien-Chi; Kingma, Idsart; Schepers, H. Martin; Herber, Sebastiaan; Veltink, Peter H.; Dennerlein, Jack T.

    2012-01-01

    This study describes a novel calibration method for six-degrees-of-freedom force/torque sensors (FTsensors) using a pre-calibrated force plate (FP) as a reference measuring device. In this calibration method, the FTsensor is rigidly connected to a FP and force/torque data are synchronously recorded

  19. A simple agar plate method, using micro-algae, for herbicide bio-assay or detection.

    Science.gov (United States)

    Wright, S J

    1975-07-01

    A simple, inexpensive method is described for the bio-assay of herbicides using micro-algae growing on agar plates. A result is obtainable in 2 days and the method is suitable for biodetection of herbicide residues, or toxicity studies on soil or aquatic pollutants.

  20. A new multiresolution finite element method based on a multiresolution quadrilateral plate element

    CERN Document Server

    Xia, YiMing

    2014-01-01

    A new multiresolution quadrilateral plate element is proposed and a multiresolution finite element method is hence presented. The multiresolution analysis (MRA) framework is formulated out of a mutually nesting displacement subspace sequence, whose basis functions are constructed of scaling and shifting on the element domain of basic node shape function. The basic node shape function is constructed by extending shape function around a specific node. The MRA endows the proposed element with the resolution level (RL) to adjust the element node number, thus modulating structural analysis accuracy accordingly. As a result, the traditional 4-node quadrilateral plate element and method is a monoresolution one and also a special case of the proposed element and method. The meshing for the monoresolution plate element model is based on the empiricism while the RL adjusting for the multiresolution is laid on the rigorous mathematical basis. The accuracy of a structural analysis is fully determined by the RL, not by th...

  1. Ultrafast Laser Engraving Method to Fabricate Gravure Plate for Printed Metal-Mesh Touch Panel

    Directory of Open Access Journals (Sweden)

    Weiyuan Chen

    2015-10-01

    Full Text Available In order to engrave gravure plate with fine lines structures, conventional art used lithography with dry/wet etching. Lithography with dry/wet etching method allows to engrave lines with smooth concave shape, but its disadvantages include difficulty in controlling aspect ratio, high and uniform in large size process, substrate material limitation due to etching solution availability, and process complexity. We developed ultra-fast laser technology to directly engrave a stainless plate, a gravure plate, to be used for fabricating 23 in. metal-mesh touch panel by gravure offset printing process. The technology employs high energy pulse to ablate materials from a substrate. Because the ultra-fast laser pulse duration is shorter than the energy dissipation time between material lattices, there is no heating issue during the ablation process. Therefore, no volcano-type protrusion on the engraved line edges occurs, leading to good printing quality. After laser engraving, we then reduce surface roughness of the gravure plate using electro-polishing process. Diamond like carbon (DLC coating layer is then added onto the surface to increase scratch resistance. We show that this procedure can fabricate gravure plate for gravure offset printing process with minimum printing linewidth 10.7 μm. A 23 in. metal-mesh pattern was printed using such gravure plate and fully functional touch panel was demonstrated in this work.

  2. 3-D vibration analysis of annular sector plates using the Chebyshev-Ritz method

    Science.gov (United States)

    Zhou, D.; Lo, S. H.; Cheung, Y. K.

    2009-02-01

    The three-dimensional free vibration of annular sector plates with various boundary conditions is studied by means of the Chebyshev-Ritz method. The analysis is based on the three-dimensional small strain linear elasticity theory. The product of Chebyshev polynomials satisfying the necessary boundary conditions is selected as admissible functions in such a way that the governing eigenvalue equation can be conveniently derived through an optimization process by the Ritz method. The boundary functions guarantee the satisfaction of the geometric boundary conditions of the plates and the Chebyshev polynomials provide the robustness for numerical calculation. The present study provides a full vibration spectrum for the thick annular sector plates, which cannot be given by the two-dimensional (2-D) theories such as the Mindlin theory. Comprehensive numerical results with high accuracy are systematically produced, which can be used as benchmark to evaluate other numerical methods. The effect of radius ratio, thickness ratio and sector angle on natural frequencies of the plates with a sector angle from 120° to 360° is discussed in detail. The three-dimensional vibration solutions for plates with a re-entrant sector angle (larger than 180°) and shallow helicoidal shells (sector angle larger than 360°) with a small helix angle are presented for the first time.

  3. A numerical method for multiple cracks in an infinite elastic plate

    Institute of Scientific and Technical Information of China (English)

    YAN Xiang-qiao; WU Hai-peng

    2005-01-01

    This article examines the interaction of multiple cracks in an infinite plate by using a numerical method. The numerical method consists of the non-singular displacement discontinuity element presented by Crouch and Starfied and the crack tip displacement discontinuity elements proposed by the author. In the numerical method implementation, the left or the right crack tip element is placed locally at the corresponding left or right crack tip on top of the constant displacement discontinuity elements that cover the entire crack surface and the other boundaries. The numerical method is called a hybrid displacement discontinuity method. The following test examples of crack problems in an infinite plate under tension are included: "center-inclined cracked plate", "interaction of two collinear cracks with equal length", "interaction of three collinear cracks with equal length", "interaction of two parallel cracks with equal length", and "interaction of one horizontal crack and one inclined crack". The present numerical results show that the numerical method is simple yet very accurate for analyzing the interaction of multiple cracks in an infinite plate.

  4. Dynamic Error Analysis Method for Vibration Shape Reconstruction of Smart FBG Plate Structure

    Directory of Open Access Journals (Sweden)

    Hesheng Zhang

    2016-01-01

    Full Text Available Shape reconstruction of aerospace plate structure is an important issue for safe operation of aerospace vehicles. One way to achieve such reconstruction is by constructing smart fiber Bragg grating (FBG plate structure with discrete distributed FBG sensor arrays using reconstruction algorithms in which error analysis of reconstruction algorithm is a key link. Considering that traditional error analysis methods can only deal with static data, a new dynamic data error analysis method are proposed based on LMS algorithm for shape reconstruction of smart FBG plate structure. Firstly, smart FBG structure and orthogonal curved network based reconstruction method is introduced. Then, a dynamic error analysis model is proposed for dynamic reconstruction error analysis. Thirdly, the parameter identification is done for the proposed dynamic error analysis model based on least mean square (LMS algorithm. Finally, an experimental verification platform is constructed and experimental dynamic reconstruction analysis is done. Experimental results show that the dynamic characteristics of the reconstruction performance for plate structure can be obtained accurately based on the proposed dynamic error analysis method. The proposed method can also be used for other data acquisition systems and data processing systems as a general error analysis method.

  5. ITSTUDIES ON THE EFFECT OF UREA ON THE COMPATIBILITY OF PMMA/PVC MIXTURES IN DMF BY A DILUTE- SOLUTION VISCOMETRY METHOD

    Institute of Scientific and Technical Information of China (English)

    Rajai Baraka; Jamil K.J. Salem; Hani Hilles; Omar Melad

    2002-01-01

    The interaction between poly(methymethacrylate) (PMMA) and poly(vinyl chloride) (PVC) has been studied in dilute urea solutions of dimethylformamide (DMF) at 28℃ using a dilute solution viscometry method. The results show that the polymer mixtures are compatible in DMF solution in the absence of urea. The influence of urea addition on the degree of compatibility of the polymer mixtures has been studied in terms of the compatibility parameters (Abm and A[r]m). It was found that the compatibility of the polymer mixtures is decreased with increasing urea addition, passing through a minimum at 0.5 M urea.

  6. The Interpretation of Dynamic Contact Angles Measured by the Wilhelmy Plate Method

    Science.gov (United States)

    Ramé

    1997-01-01

    We present an analysis for properly interpreting apparent dynamic contact angles measured using the Wilhelmy plate method at low capillary numbers, Ca. This analysis removes the ambiguity in current dynamic measurements which interpret data with the same formula as static measurements. We properly account for all forces, including viscous forces, acting on the plate as it moves into or out of a liquid bath. Our main result, valid at O(1) as Ca --> 0, relates the apparent dynamic contact angle to material-dependent, geometry-independent parameters necessary for describing dynamic wetting of a system. The special case of the apparent contact angle = pi/2 was solved to O(Ca). This O(Ca) solution can guide numerical work necessary for higher Ca's and arbitrary values of the apparent contact angle. These results make the Wilhelmy plate a viable method for determining material parameters for dynamic spreading.

  7. The dynamic flexibility method in structural dynamics: Application to nonuniform beams and plates and to cavity-backed plates

    Science.gov (United States)

    Lee, Jinkyo

    1993-01-01

    Efficient and accurate analytical or semi-analytical solutions have been developed for the dynamics of one and two dimensional linear structures employing elemental dynamic flexibility formulation. This dissertation is divided into three parts. In the first, the elemental flexibility formulation is developed for Euler-Bernoulli beams having discontinuous section properties, which can be viewed as the synthesis of uniform beams, and the exactness of the solution is established. In the second, the elemental flexibility formulation is extended to thin rectangular plates having Levy boundary conditions, and conditions under which the exact solution can be achieved are presented. In the third, the structural-acoustic problem of Helmholtz fluid enclosed by a partially flexible cavity is posed and solved. Here, a concise analytical representation of the structural dynamics is used in conjunction with a boundary element approach for the fluid medium to give an efficient and accurate semi-analytical solution. All three sections are organized along similar lines. Following an introduction and review of the pertinent literature, the governing equations are derived and solved, a series of example problems is presented, the results from the examples are compared with similar results from the literature, and efficacy of the method when compared with other methods is discussed. This is followed by a general conclusions section and a series of appendices.

  8. High-Frequency Dynamic Analysis of Plates in Thermal Environments Based on Energy Finite Element Method

    Directory of Open Access Journals (Sweden)

    Di Wang

    2015-01-01

    Full Text Available The energy density governing equation to analyze the high-frequency dynamic behavior of plates in thermal environments is derived in this paper, in which the thermal effects are considered to change the membrane stress state and temperature dependent material properties of plates. Then the thermal effects on the energy reflection and transmission coefficients are dealt with hereof. Based on the above, an EFEM (energy finite element method based approximate approach for the energy analysis of coupled plates under nonuniform thermal environments is proposed. The approach could be conducted by three steps: (1 thermal analysis, (2 thermal stress analysis, and (3 forming element matrixes, joint matrixes, and the whole EFEM formulation for the energy analysis. The same mesh model is used for all the three steps. The comparison between EFEM results and classical modal superposition method results of simply supported plates in various uniform thermal environments and coupled plates in nonuniform thermal environments demonstrated that the derived energy governing equation and the proposed approach described well the smooth time- and locally space-averaged energy density. It is found that the distributions and levels of energy density are affected by thermal effects, and the variation trends are related to exciting frequency.

  9. Dynamic Stationary Response of Reinforced Plates by the Boundary Element Method

    Directory of Open Access Journals (Sweden)

    Luiz Carlos Facundo Sanches

    2007-01-01

    Full Text Available A direct version of the boundary element method (BEM is developed to model the stationary dynamic response of reinforced plate structures, such as reinforced panels in buildings, automobiles, and airplanes. The dynamic stationary fundamental solutions of thin plates and plane stress state are used to transform the governing partial differential equations into boundary integral equations (BIEs. Two sets of uncoupled BIEs are formulated, respectively, for the in-plane state (membrane and for the out-of-plane state (bending. These uncoupled systems are joined to form a macro-element, in which membrane and bending effects are present. The association of these macro-elements is able to simulate thin-walled structures, including reinforced plate structures. In the present formulation, the BIE is discretized by continuous and/or discontinuous linear elements. Four displacement integral equations are written for every boundary node. Modal data, that is, natural frequencies and the corresponding mode shapes of reinforced plates, are obtained from information contained in the frequency response functions (FRFs. A specific example is presented to illustrate the versatility of the proposed methodology. Different configurations of the reinforcements are used to simulate simply supported and clamped boundary conditions for the plate structures. The procedure is validated by comparison with results determined by the finite element method (FEM.

  10. Experimental method for and theoretical research on defect tolerance of fixed plate based on damage mechanics

    Institute of Scientific and Technical Information of China (English)

    Zhan Zhixin; Hu Weiping; Zhang Miao; Zhu Yuefa; Meng Qingchun

    2013-01-01

    An experimental method and a theoretical analysis based on continuum damage mechan-ics are applied for the defects tolerance of fixed plate. The defects type studied in this article is scratch, which is considered a typical defect on fixed plate according to the engineering practice. The general approach to the defects tolerance analysis of scratched fixed plate is presented. The method of fatigue life prediction for standard notched specimens has been established on the basis of continuum damage mechanics. For the purpose of obtaining the influence law of fatigue life in consequence of scratches, fatigue experiments of standard notched specimens and scratched specimens have been done. Evalu-ation of the fatigue life of scratched fixed plate has been carried out. And the value of scratch defects permissible to the condition of safety service life has been worked out. According to the results of the-oretical calculations, the fatigue experiment of scratched fixed plate has been performed. The outcome shows that the theoretical prediction tallies with the experimental results.

  11. Analysis of a novel field dilution method for testing samples that exceed the analytic range of point-of-care blood lead analyzers.

    Science.gov (United States)

    Neri, Antonio James; Roy, Joannie; Jarrett, Jeffery; Pan, Yi; Dooyema, Carrie; Caldwell, Kathleen; Umar-Tsafe, Nasir Tsafe; Olubiyo, Ruth; Brown, Mary Jean

    2014-01-01

    Investigators developed and evaluated a dilution method for the LeadCare II analyzer (LCII) for blood lead levels >65 μg/dL, the analyzer's maximum reporting value. Venous blood samples from lead-poisoned children were initially analyzed in the field using the dilution method. Split samples were analyzed at the US Centers for Disease Control and Prevention (CDC) laboratory using both the dilution method and inductively coupled plasma-mass spectrometry (ICP-MS). The concordance correlation coefficient of CDC LCII vs. ICP-MS values (N = 211) was 0.976 (95 % confidence interval (CI) 0.970-0.981); of Field LCII vs. ICP-MS (N = 68) was 0.910 (95% CI 0.861-0.942), and CDC LCII vs. Field LCII (N = 53) was 0.721 (95% CI 0.565-0.827). Sixty percent of CDC and 54% of Field LCII values were within ±10% of the ICP-MS value. Results from the dilution method approximated ICP-MS values and were useful for field-based decision-making. Specific recommendations for additional evaluation are provided.

  12. HE NEW METHOD OF MINIMALLY INVASIVE OSTEOSYTHESIS OF HUMERAL SHAFT FRACTURES WITH HELICAL PLATES

    Directory of Open Access Journals (Sweden)

    A. Y. Kochish

    2016-01-01

    Full Text Available The purpose of investigation is to approve the new method of minimally invasive plate osteosynthesis in cases of diaphyseal humeral shaft fractures with helical plate.Materials and methods. During experimental cadaveric part of the study implantation of long helical plate on humerus using minimally invasive technique on 14 fresh cadaveric shoulders was done. plate was inserted from two incisions 3-5 cm long in the upper part of the shoulder on the lateral side and in the lower part on the anterior side. Clinical part of the study included 31 patients with isolated humeral shaft fractures and humeral shaft fractures associated with fractures of proximal humerus and treated by minimally invasive fixation with helical plate.Results. Cadaveric study included preparation and special measuring and showed that implantation of the helical plate in proposed way gives safe distances between plate and axial, radial, musculocutaneous, median nerves, main humeral vessels and tendon of the long head of the biceps.Results of the clinical part of the study: radiological evidence of bone healing were observed on the 12 weeks in 10 from 28 cases (36%, on the 18 weeks in 18 from 25 (72%, on the 24 weeks in all 25 cases (100%. On the 24 weeks after surgery results on the DASH scale in average were 13±3,6 (from 3 to 36. Where in good results were in 17 (68% cases, satisfactory in 8 (32% cases. On the Constant Shoulder Score at the same time averege results were 80±4,63 (from 60 to 91. Exellent result was in 7 (28% cases, good in 12 (48%, satisfactory in 5 (20% cases and bad in one (4% case with subacromial impidgement after wrong plate positioning. There were no any cases of vascular and neurological complications and nonunions.Conclusion. Minimally invasive fixation of humeral shaft fractures with helical plates is safe and effective method of surgical treatment with good dynamic of functional rehabilitation and can be recommended for clinical use.

  13. Validating the plate mapping method: Comparing drawn foods and actual foods of university students in a cafeteria.

    Science.gov (United States)

    Sharp, David E

    2016-05-01

    To examine effects of plate size on meals, I developed a method I label plate mapping. To validate plate mapping, a quasi-experimental between participants study was conducted that asked university students to accurately draw their lunch meal. Participants were randomized into groups where they were asked either pre-consumption or post-consumption to draw their lunch on either a 9″ or 11″ paper plate. Coding plate drawings for total meal size revealed that students drew bigger meals on larger plates and participant meal size drawings were more accurate when the plate provided was the same size as the meal plate used. Gender moderated meal size drawings, with women generally drawing meals that were more highly correlated and similarly sized to actual meals when compared to the drawings of men. Overall, the size of plate drawings was highly correlated with the size of actual foods, which provides support for the validity of the method of plate mapping. These findings suggest that plate mapping can be applied to estimate meal size and assess sensitivity to plate size. Gaining a better understanding of the mechanisms and processes that influence food consumption habits can help increase awareness of these cues for both academics as well as for consumers of food and benefit short- and long-term health goals.

  14. Photography - Determination of thiosulphate and other residual chemicals in processed photographic films, plates and papers - Methylene blue photometric method and silver sulphide densitometric method

    CERN Document Server

    International Organization for Standardization. Geneva

    1977-01-01

    Photography - Determination of thiosulphate and other residual chemicals in processed photographic films, plates and papers - Methylene blue photometric method and silver sulphide densitometric method

  15. Accurate calculation methods for natural frequencies of plates with special attention to the higher modes

    NARCIS (Netherlands)

    Oosterhout, G.M.; Hoogt, van der P.J.M.; Spiering, R.M.E.J.

    1995-01-01

    Various computational methods have been studied with respect to their suitability for obtaining very accurate solutions of plate vibration problems, especially for the higher modes. Because of the interest in the higher modes, also higher order effects such as transverse shear deformation and rotati

  16. Vibration analysis of cracked plates using the extended finite element method

    Energy Technology Data Exchange (ETDEWEB)

    Bachene, M. [University of Medea, Department of Mechanical Engineering, Medea (Algeria); Tiberkak, R. [University of Blida, Department of Mechanical Engineering, Blida (Algeria); Rechak, S. [National Polytechnic School of Algiers, Laboratory of Mechanical Engineering and Development, Algiers (Algeria)

    2009-03-15

    In the present paper, the extended finite element method (X-FEM) is adopted to analyze vibrations of cracked plates. Mindlin's plate theory taking into account the effects of shear deformation and rotatory inertia is included in the development of the model. First, conventional FEM without any discontinuity is carried out, then the enrichment proposed by Moes et al. (Int J Numer Methods Eng 46, 131-150, 1999) of nodal elements containing cracks is added to the FEM formulation. Numerical implementation of enriched elements by discontinuous functions is performed, and thus dynamic equations (stiffness and mass matrices) are established. A FORTRAN computer code based on the X-FEM formulation is hence developed. Rectangular and square plates containing through-edge and central cracks with different boundary conditions are considered. The subspace iteration method is used to solve the eigenvalue problem. Natural frequencies as well as the corresponding eigenfunctions are consequently calculated as a function of the crack length. The obtained results show that the X-FEM is an efficient method in the dynamic analysis of plates containing discontinuities. (orig.)

  17. THREE-DIMENSIONAL ANALYSIS OF FUNCTIONALLY GRADED PLATE BASED ON THE HAAR WAVELET METHOD

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A three-dimensional analysis of a simply-supported functionally graded rectangular plate with an arbitrary distribution of material properties is made using a simple and effective method based on the Haar wavelet. With good features in treating singularities, Haar series solution converges rapidly for arbitrary distributions, especially for the case where the material properties change rapidly in some regions. Through numerical examples the influences of the ratio of material constants on the top and bottom surfaces and different material gradient distributions on the structural response of the plate to mechanical stimuli are studied.

  18. Interaction of Shock Waves in Cement Mortar Plate Investigated by the Digital Speckle Correlation Method

    Institute of Scientific and Technical Information of China (English)

    LI Xu-Dong; LIU Kai-Xin; ZHANG Guang-Sheng; WEN Shang-Gang; TAN Fu-Li

    2008-01-01

    @@ Interaction of shock waves in cement mortar plate is studied by digital speckle correlation method and digital high-speed photography technique. When the plates were destroyed by two detonators exploding at the same time, variation of shock wave field is obtained. Experimental results show that the interaction of shock waves will result in a nonlinear huge increase of local normal strain, leading to large deformation and serious destruction. However, the occurrence of this strongly nonlinear phenomenon sensitively depends on the interval between detonators, and it will only appear when the interval is smaller than the diameter of the region where shock waves exist.

  19. Effect of Welding Parameters on Dilution and Weld Bead Geometry in Cladding

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The effect of pulsed gas metal arc welding (GMAW) variables on the dilution and weld bead geometry in cladding X65 pipeline steel with 316L stainless steel was studied. Using a full factorial method, a series of experiments were carried out to know the effect of wire feed rate, welding speed, distance between gas nozzle and plate, and the vertical angle of welding on dilution and weld bead geometry. The findings indicate that the dilution of weld metal and its dimension i.e. width, height and depth increase with the feed rate, but the contact angle of the bead decreases first and then increases. Meantime, welding speed has an opposite effect except for dilution. There is an interaction effect between welding parameters at the contact angle. The results also show forehand welding or decreasing electrode extension decrease the angle of contact. Finally,a mathematical model is contrived to highlight the relationship between welding variables with dilution and weld bead geometry.

  20. Nanocrystalline silicon and silicon quantum dots formation within amorphous silicon carbide by plasma enhanced chemical vapour deposition method controlling the Argon dilution of the process gases

    Energy Technology Data Exchange (ETDEWEB)

    Kole, Arindam; Chaudhuri, Partha, E-mail: erpc@iacs.res.in

    2012-11-01

    Structural and optical properties of the amorphous silicon carbide (a-SiC:H) thin films deposited by radio frequency plasma enhanced chemical vapour deposition method from a mixture of silane (SiH{sub 4}) and methane (CH{sub 4}) diluted in argon (Ar) have been studied with variation of Ar dilution from 94% to 98.4%. It is observed that nanocrystalline silicon starts to form within the a-SiC:H matrix by increasing the dilution to 96%. With further increase in Ar dilution to 98% formation of the silicon nanocrystals (nc-Si) with variable size is enhanced. The optical band gap (E{sub g}) of the a-SiC:H film decreases from 2.0 eV to 1.9 eV with increase in Ar dilution from 96% to 98% as the a-SiC:H films gradually become Si rich. On increasing the Ar dilution further to 98.4% leads to the appearance of crystalline silicon quantum dots (c-Si q-dots) of nearly uniform size of 3.5 nm. The quantum confinement effect is apparent from the sharp increase in the E{sub g} value to 2.6 eV. The phase transformation phenomenon from nc-Si within the a-SiC:H films to Si q-dot were further studied by high resolution transmission electron microscopy and the grazing angle X-ray diffraction spectra. A relaxation in the lattice strain has been observed with the formation of Si q-dots.

  1. A Review of Metallic Bipolar Plates for Proton Exchange Membrane Fuel Cells: Materials and Fabrication Methods

    Directory of Open Access Journals (Sweden)

    Shahram Karimi

    2012-01-01

    Full Text Available The proton exchange membrane fuel cell offers an exceptional potential for a clean, efficient, and reliable power source. The bipolar plate is a key component in this device, as it connects each cell electrically, supplies reactant gases to both anode and cathode, and removes reaction products from the cell. Bipolar plates have been fabricated primarily from high-density graphite, but in recent years, much attention has been paid to developing cost-effective and feasible alternative materials. Two different classes of materials have attracted attention: metals and composites. This paper offers a comprehensive review of the current research being carried out on metallic bipolar plates, covering materials and fabrication methods.

  2. Characterization of nano-sized SiC@Ni composite fabricated by electroless plating method.

    Science.gov (United States)

    Xu, Zhan; Chen, Yigang

    2013-02-01

    A nano-sized SiC@Ni composite was prepared by simple electroless plating method. Nickel can be reduced by Na2H2PO2 under the catalysis of Pd to despite onto the surface of SiC nanoparticles. The composite structure was characterized by means of TEM images, XRD and the components were analyzed using EDS. The coating layer on the SiC particles was several nanometers thick and mainly in a form of fine Ni crystalline grain and amorphous Ni-P alloy. By increasing the concentration of Na2H2PO2 in the plating bath, the uniformity of the coating layer can be improved obviously. Both of the magnetism and crystallinity of Ni coatings depends on the P content in the coating which can be decreased by increasing the pH values of plating solutions. The SiC@Ni particles exhibited soft magnetic characteristics.

  3. Plate measurement techniques and reduction methods used by the West German satellite observers, and resulting consequences for the observation

    Science.gov (United States)

    Deker, H.

    1971-01-01

    The West German tracking stations are equipped with ballistic cameras. Plate measurement and plate reduction must therefore follow photogrammetric methods. Approximately 100 star positions and 200 satellite positions are measured on each plate. The mathematical model for spatial rotation of the bundle of rays is extended by including terms for distortion and internal orientation of the camera as well as by providing terms for refraction which are computed for the measured coordinates of the star positions on the plate. From the measuring accuracy of the plate coordinates it follows that the timing accuracy for the exposures has to be about one millisecond, in order to obtain a homogeneous system.

  4. Single strain isolation method for cell culture-adapted hepatitis C virus by end-point dilution and infection.

    Directory of Open Access Journals (Sweden)

    Nao Sugiyama

    Full Text Available The hepatitis C virus (HCV culture system has enabled us to clarify the HCV life cycle and essential host factors for propagation. However, the virus production level of wild-type JFH-1 (JFH-1/wt is limited, and this leads to difficulties in performing experiments that require higher viral concentrations. As the cell culture-adapted JFH-1 has been reported to have robust virus production, some mutations in the viral genome may play a role in the efficiency of virus production. In this study, we obtained cell culture-adapted virus by passage of full-length JFH-1 RNA-transfected Huh-7.5.1 cells. The obtained virus produced 3 log-fold more progeny viruses as compared with JFH-1/wt. Several mutations were identified as being responsible for robust virus production, but, on reverse-genetics analysis, the production levels of JFH-1 with these mutations did not reach the level of cell culture-adapted virus. By using the single strain isolation method by end-point dilution and infection, we isolated two strains with additional mutations, and found that these strains have the ability to produce more progeny viruses. On reverse-genetics analysis, the strains with these additional mutations were able to produce robust progeny viruses at comparable levels as cell culture-adapted JFH-1 virus. The strategy used in this study will be useful for identifying strains with unique characteristics, such as robust virus production, from a diverse population, and for determining the responsible mutations for these characteristics.

  5. 有限稀释法筛选轮状病毒LD9株纯化方法的建立及应用%Development and application of limiting dilution method for screening rotavirus LD9

    Institute of Scientific and Technical Information of China (English)

    寇桂英; 余黎; 朱传凤; 王名强; 周旭

    2012-01-01

    目的:建立有限稀释法克隆纯化轮状病毒的试验方法,筛选出感染性强、遗传特性稳定的轮状病毒基因重配株LD9.方法:梯度稀释LD9毒种,用5个稀释度(10-4~10-8)的病毒感染铺满单层Vero细胞的96孔板细胞,培养6d,- 20℃冻融,培养物传代至24孔板继续培养6d,显微镜下观察细胞病变(CPE),- 20℃冻融后检测.以相同方法重复克隆纯化3次,筛选获得病毒滴度稳定、具有稳定遗传特性的纯化病毒,由T25、T75到2,4,10层细胞工厂逐级放大培养.结果:筛选出适用于疫苗生产用的遗传特性稳定、感染性强的LD9疫苗候选株.结论:建立了适用于轮状病毒克隆纯化的筛选方法.%Objective; To establish the limiting dilution method for purifying rotavirus; to screen and obtain reassortant rotavirus strain LD9 with strong infectivity and genetic stability. Methods; A serial 10 time dilution (10 -4~10-8) of the ressortant rotavirus LD9 were prepared, the virus was inoculated in 96-well plates with monolayer of Vero cells. The cell culture 6 days postinfection was frozen at - 20℃ and then thawed. The subpassage was cultured in 24-well plate for 6 days, and CPE of cells was observed under a microscope. Then the culture was examined after freezing-thawing at - 20 ℃ and room temperature. The purification process was repeated three times to screen and obtain the highly-infectious reassortant rotavirus with genetic stability. The subpassage cultures were then enlarged into T25, T75, 2-Layer, 4-Layer, 10-layer cell factories gradually. Results; We had screened and obtained the highly-infectious reassortant rotavirus with genetic stability. Conclusion; The limiting dilution approach of purifying rotavirus has been established.

  6. Dynamic buckling analysis of delaminated composite plates using semi-analytical finite strip method

    Science.gov (United States)

    Ovesy, H. R.; Totounferoush, A.; Ghannadpour, S. A. M.

    2015-05-01

    The delamination phenomena can become of paramount importance when the design of the composite plates is concerned. In the current study, the effect of through-the-width delamination on dynamic buckling behavior of a composite plate is studied by implementing semi-analytical finite strip method. In this method, the energy and work integrations are computed analytically due to the implementation of trigonometric functions. Moreover, the method can lead to converged results with comparatively small number of degrees of freedom. These features have made the method quite efficient. To account for delamination effects, displacement field is enriched by adding appropriate terms. Also, the penetration of the delamination surfaces is prevented by incorporating an appropriate contact scheme into the time response analysis. Some selected results are validated against those available in the literature.

  7. The vibration and stability analysis of moderate thick plates by the method of lines

    Science.gov (United States)

    Tang, Shou-Gao; Yuan, Si

    1992-06-01

    The method of lines based on Hu Hai-chang's theory for the vibration and stability of moderate thick plates is developed. The standard nonlinear ordinary differential equation (ODE) system for natural frequencies and critical load is given by use of ODE techniques; any indicated eigenvalue could be obtained directly from ODE solver by employing the so-called initial eigenfunction technique instead of the mode orthogonality condition. Numerical examples show that the present method is very effective and reliable.

  8. Evaluation of the 3M Petrifilm Enterobacteriaceae Count plate method for the enumeration of Enterobacteriaceae in foods.

    Science.gov (United States)

    Silbernagel, Karen M; Lindberg, Kathryn G

    2002-09-01

    Results of the 3M Petrifilm Enterobacteriaceae Count (EB) plate method were compared with those of the standard violet red bile glucose agar (VRBG) method for the detection and enumeration of Enterobacteriaceae. Studies involving 107 bacterial strains demonstrated that the Petrifilm EB plate method is as sensitive as and more selective than the VRBG method. Sixty of the 62 pure Enterobacteriaceae cultures were recovered by both methods. In addition, 38 of the 45 non-Enterobacteriaceae organisms did not grow on the Petrifilm EB plate, while 28 of the 45 non-Enterobacteriaceae organisms did not grow on the VRBG plate. Colony counts from 174 naturally contaminated and 120 artificially inoculated dairy and nondairy food samples showed that the Petrifilm EB plate method performed as well as or better than the standard VRBG method for the enumeration of Enterobacteriaceae.

  9. Determination of thyroid hormones in mouse tissues by isotope-dilution microflow liquid chromatography-mass spectrometry method.

    Science.gov (United States)

    De Angelis, Meri; Giesert, Florian; Finan, Brian; Clemmensen, Christoffer; Müller, Timo D; Vogt-Weisenhorn, Daniela; Tschöp, Matthias H; Schramm, Karl-Werner

    2016-10-15

    Thyroid hormones (THs) play a critical role in the regulation of many biological processes such as growth, metabolism and development both in humans and wildlife. In general, TH levels are measured by immunoassay (IA) methods but the specificity of the antibodies used in these assays limits selectivity. In the last decade, several analytical methods using liquid chromatography-mass spectrometry (LC-MS) and tandem mass spectrometry (LC-MS/MS) have been developed to measure THs. These new techniques proved to be more accurate than the IA analysis and they were widely used for the determination of TH level in different human and animal tissues. A large part of LC-MS/MS methods described in literature employed between 200 and 500mg of sample, however this quantity can be considered too high especially when preclinical studies are conducted using mice as test subjects. Thus an analytical method that reduces the amount of tissue is essential. In this study, we developed a procedure for the analysis of six THs; L-thyroxine (T4), 3,3',5-triiodo-l-thyronine (T3), 3,3',5'-triiodo-l-thyronine (rT3), 3,5-diiodo-l-thyronine (rT2), 3,3'-diiodo-l-thyronine (T2), 3-iodo-l-thyronine (T1) using isotope ((13)C6-T4, (13)C6-T3, (13)C6-rT3, (13)C6-T2) dilution liquid chromatography-mass spectrometry. The major difference with previously described methods lies in the utilization of a nano-UPLC (Ultra Performance Liquid Chromatography) system in micro configuration. This approach leads to a reduction compared to the published methods, of column internal diameter, flow rate, and injected volume. The result of all these improvements is a decrease in the amount of sample necessary for the analysis. The method was tested on six different mouse tissues: liver, heart, kidney, muscle, lung and brown adipose tissue (BAT). The nano-UPLC system was interfaced with a quadrupole time-of-flight mass spectrometer (Q-TOF2-MS) using the positive ion mode electrospray ionization. In our analytical method

  10. AN EFFECTIVE BOUNDARY ELEMENT METHOD FOR ANALYSIS OF CRACK PROBLEMS IN A PLANE ELASTIC PLATE

    Institute of Scientific and Technical Information of China (English)

    YAN Xiang-qiao

    2005-01-01

    A simple and effective boundary element method for stress intensity factor calculation for crack problems in a plane elastic plate is presented. The boundary element method consists of the constant displacement discontinuity element presented by Crouch and Starfield and the crack-tip displacement discontinuity elements proposed by YAN Xiangqiao. In the boundary element implementation the left or the right crack-tip displacement discontinuity element was placed locally at the corresponding left or right each crack tip on top of the constant displacement discontinuity elements that cover the entire crack surface and the other boundaries. Test examples ( i. e. , a center crack in an infinite plate under tension, a circular hole and a crack in an infinite plate under tension) are included to illustrate that the numerical approach is very simple and accurate for stress intensity factor calculation of plane elasticity crack problems. In addition, specifically, the stress intensity factors of branching cracks emanating from a square hole in a rectangular plate under biaxial loads were analysed. These numerical results indicate the present numerical approach is very effective for calculating stress intensity factors of complex cracks in a 2-D finite body, and are used to reveal the effect of the biaxial loads and the cracked body geometry on stress intensity factors.

  11. Preparation of zeolite a coatings on copper plates by using the substrate heating method

    Directory of Open Access Journals (Sweden)

    S. Teber

    2010-12-01

    Full Text Available The substrate heating method was used to grow zeolite 4A coatings on copper plates. The reaction mixture was kept at 25º C, while the plate was heated to a higher temperature. In some of the synthesis experiments performed, the reaction mixture was circulated in the system. The coatings prepared were characterized by X-ray diffraction and scanning electron microscopy. It was demonstrated that crystalline and pure zeolite 4A coatings could be formed on copper by using the substrate heating method from a highly alkaline solution, in which dissolution and oxidation of the copper plates took place. A coating with about 310 µm mass equivalent thickness could be grown on copper after 72 h of synthesis. The thickness decreased when circulation was applied. Compared to coatings previously prepared on stainless steel plates under similar experimental conditions, thicker coatings were grown on copper. It is possible that the roughened surface of copper in the highly alkaline reaction mixture provided a higher number of nucleation sites.

  12. Analysis of Nonlinear Vibration of Hard Coating Thin Plate by Finite Element Iteration Method

    Directory of Open Access Journals (Sweden)

    Hui Li

    2014-01-01

    Full Text Available This paper studies nonlinear vibration mechanism of hard coating thin plate based on macroscopic vibration theory and proposes finite element iteration method (FEIM to theoretically calculate its nature frequency and vibration response. First of all, strain dependent mechanical property of hard coating is briefly introduced and polynomial method is adopted to characterize the storage and loss modulus of coating material. Then, the principle formulas of inherent and dynamic response characteristics of the hard coating composite plate are derived. And consequently specific analysis procedure is proposed by combining ANSYS APDL and self-designed MATLAB program. Finally, a composite plate coated with MgO + Al2O3 is taken as a study object and both nonlinear vibration test and analysis are conducted on the plate specimen with considering strain dependent mechanical parameters of hard coating. Through comparing the resulting frequency and response results, the practicability and reliability of FEIM have been verified and the corresponding analysis results can provide an important reference for further study on nonlinear vibration mechanism of hard coating composite structure.

  13. Waves on Thin Plates: A New (Energy Based) Method on Localization

    Science.gov (United States)

    Turkaya, Semih; Toussaint, Renaud; Kvalheim Eriksen, Fredrik; Lengliné, Olivier; Daniel, Guillaume; Grude Flekkøy, Eirik; Jørgen Måløy, Knut

    2016-04-01

    Noisy acoustic signal localization is a difficult problem having a wide range of application. We propose a new localization method applicable for thin plates which is based on energy amplitude attenuation and inversed source amplitude comparison. This inversion is tested on synthetic data using a direct model of Lamb wave propagation and on experimental dataset (recorded with 4 Brüel & Kjær Type 4374 miniature piezoelectric shock accelerometers, 1 - 26 kHz frequency range). We compare the performance of this technique with classical source localization algorithms, arrival time localization, time reversal localization, localization based on energy amplitude. The experimental setup consist of a glass / plexiglass plate having dimensions of 80 cm x 40 cm x 1 cm equipped with four accelerometers and an acquisition card. Signals are generated using a steel, glass or polyamide ball (having different sizes) quasi perpendicular hit (from a height of 2-3 cm) on the plate. Signals are captured by sensors placed on the plate on different locations. We measure and compare the accuracy of these techniques as function of sampling rate, dynamic range, array geometry, signal to noise ratio and computational time. We show that this new technique, which is very versatile, works better than conventional techniques over a range of sampling rates 8 kHz - 1 MHz. It is possible to have a decent resolution (3cm mean error) using a very cheap equipment set. The numerical simulations allow us to track the contributions of different error sources in different methods. The effect of the reflections is also included in our simulation by using the imaginary sources outside the plate boundaries. This proposed method can easily be extended for applications in three dimensional environments, to monitor industrial activities (e.g boreholes drilling/production activities) or natural brittle systems (e.g earthquakes, volcanoes, avalanches).

  14. A passive guard for low thermal conductivity measurement of small samples by the hot plate method

    Science.gov (United States)

    Jannot, Yves; Degiovanni, Alain; Grigorova-Moutiers, Veneta; Godefroy, Justine

    2017-01-01

    Hot plate methods under steady state conditions are based on a 1D model to estimate the thermal conductivity, using measurements of the temperatures T 0 and T 1 of the two sides of the sample and of the heat flux crossing it. To be consistent with the hypothesis of the 1D heat flux, either a hot plate guarded apparatus is used, or the temperature is measured at the centre of the sample. On one hand the latter method can be used only if the ratio thickness/width of the sample is sufficiently low and on the other hand the guarded hot plate method requires large width samples (typical cross section of 0.6  ×  0.6 m2). That is why both methods cannot be used for low width samples. The method presented in this paper is based on an optimal choice of the temperatures T 0 and T 1 compared to the ambient temperature T a, enabling the estimation of the thermal conductivity with a centered hot plate method, by applying the 1D heat flux model. It will be shown that these optimal values do not depend on the size or on the thermal conductivity of samples (in the range 0.015-0.2 W m-1 K-1), but only on T a. The experimental results obtained validate the method for several reference samples for values of the ratio thickness/width up to 0.3, thus enabling the measurement of the thermal conductivity of samples having a small cross-section, down to 0.045  ×  0.045 m2.

  15. Key techniques and applications of adaptive growth method for stiffener layout design of plates and shells

    Science.gov (United States)

    Ding, Xiaohong; Ji, Xuerong; Ma, Man; Hou, Jianyun

    2013-11-01

    The application of the adaptive growth method is limited because several key techniques during the design process need manual intervention of designers. Key techniques of the method including the ground structure construction and seed selection are studied, so as to make it possible to improve the effectiveness and applicability of the adaptive growth method in stiffener layout design optimization of plates and shells. Three schemes of ground structures, which are comprised by different shell elements and beam elements, are proposed. It is found that the main stiffener layouts resulted from different ground structures are almost the same, but the ground structure comprised by 8-nodes shell elements and both 3-nodes and 2-nodes beam elements can result in clearest stiffener layout, and has good adaptability and low computational cost. An automatic seed selection approach is proposed, which is based on such selection rules that the seeds should be positioned on where the structural strain energy is great for the minimum compliance problem, and satisfy the dispersancy requirement. The adaptive growth method with the suggested key techniques is integrated into an ANSYS-based program, which provides a design tool for the stiffener layout design optimization of plates and shells. Typical design examples, including plate and shell structures to achieve minimum compliance and maximum bulking stability are illustrated. In addition, as a practical mechanical structural design example, the stiffener layout of an inlet structure for a large-scale electrostatic precipitator is also demonstrated. The design results show that the adaptive growth method integrated with the suggested key techniques can effectively and flexibly deal with stiffener layout design problem for plates and shells with complex geometrical shape and loading conditions to achieve various design objectives, thus it provides a new solution method for engineering structural topology design optimization.

  16. A TIME DOMAIN METHOD FOR QUASI-STATIC ANALYSIS OF VISCOELASTIC THIN PLATES

    Institute of Scientific and Technical Information of China (English)

    张能辉; 程昌钧

    2001-01-01

    Based on the Boltzmann's superposition principles of linear viscoelastic materials for quasi-static problems of viscoelastic thin plates was given. By the Galerkin method in spatial domain, the original integro-partial-differential system could be transformed into an integral system. The latter further was reduced to a differential system by using the new method for temporal domain presented in this paper. Numerical results show that compared with the ordinary finite difference method, the new method in this paper is simpler to operate and has some advantages, such as, no storage and quicker computational speed etc.

  17. Nonconforming stabilized combined finite element method for Reissner-Mindlin plate

    Institute of Scientific and Technical Information of China (English)

    Min-fu FENG; Yan YANG; Tian-xiao ZHOU

    2009-01-01

    Based on combination of two variational principles, a nonconforming sta-bilized finite element method is presented for the Reissner-Mindlin plates. The method is convergent when the finite element space is energy-compatible. Error estimates are derived. In particular, three finite element spaces are applied in the computation. Nu-merical results show that the method is insensitive to the mesh distortion and has better performence than the MITC4 and DKQ methods. With properly chosen parameters, high accuracy can be obtained at coarse meshes.

  18. Characterization of dilute magnetic semiconducting transition metal doped ZnO thin films by sol–gel spin coating method

    Energy Technology Data Exchange (ETDEWEB)

    Vijayaprasath, G.; Murugan, R. [Department of Physics, Alagappa University, Karaikudi 630004, Tamil Nadu (India); Ravi, G., E-mail: gravicrc@gmail.com [Department of Physics, Alagappa University, Karaikudi 630004, Tamil Nadu (India); Mahalingam, T. [Department of Electrical and Computer Engineering, Ajou University, Suwon 443-749 (Korea, Republic of); Hayakawa, Y. [Research Institute of Electronics, Shizuoka University, Hamamatsu 432-8011 (Japan)

    2014-09-15

    Graphical abstract: - Highlights: • Diluted magnetic semiconducting TM (Ni, Mn, Co) doped ZnO thin films were fabricated by sol–gel spin coating technique. • The XRD analyses revealed that the TM (Ni, Mn, Co) doped ZnO films have hexagonal wurtzite structure. • Photoluminescence and micro-Raman spectra were interpreted for TM (Ni, Mn, Co) doped ZnO thin films. • SEM morphology studies were made for Zn{sub 0.97} Ni{sub 0.03}O, Zn{sub 0.97} Mn{sub 0.03}O and Zn{sub 0.97} Co{sub 0.03}O thin films. • Room temperature ferromagnetism was observed in TM (Ni, Mn, Co) doped ZnO thin films. - Abstract: Pure and transition metal (TM = Ni, Mn, Co) doped zinc oxide (ZnO) thin films were prepared by sol–gel spin coating method with a concentration of 0.03 mol% of transition metals. X-ray diffraction studies revealed the polycrystalline nature of the films with the presence of hexagonal wurtzite structure. UV transmittance spectra showed that all the films are highly transparent in the visible region and in the case of doped ZnO thin films, d–d transition was observed in the violet region due to the existence of crystalline defects and grain boundaries. The optical band gap of the films decreases with increasing orbital occupation numbers of 3d electrons due to the orbital splitting of magnetic ions. Ultraviolet and near-infrared electronic transitions were observed which reveals a strong relationship with the doping of transition metal into ZnO site. The observed luminescence in the green, violet and red regions strongly depends on the doping elements owing to the different oxygen vacancy, oxygen interstitial, and surface morphology. The surface morphology of thin films was investigated by scanning electron microscope (SEM). The energy dispersive X-ray analysis (EDX) confirmed the stoichiometric composition of the TM doped ZnO thin films. Magnetic measurements at room temperature exhibited well defined ferromagnetic features of the thin films.

  19. Validation of a two-plate microbiological method for screening antibiotic residues in shrimp tissue.

    Science.gov (United States)

    Dang, Pham Kim; Degand, Guy; Danyi, Sophie; Pierret, Gilles; Delahaut, Philippe; Ton, Vu Dinh; Maghuin-Rogister, Guy; Scippo, Marie-Louise

    2010-07-05

    Microbiological inhibition screening tests could play an important role to detect residues of antibiotics in the different animal food products, but very few are available for the aquaculture products in general, and for shrimps in particular. A two-plate microbiological method to screen shrimp for residues of the most commonly used antibiotics has been developed and validated according to criteria derived from the European Commission Decision 2002/657/CE. Bacillus subtilis was used as a sensitive strain to target antibiotics. Culture conditions on Petri plates (pH of medium) were selected to enhance the capacity of antibiotic detection. Antibiotic residues were extracted from shrimps using acetonitrile/acetone (70/30, v/v) before application on Petri plates seeded with B. subtilis. The method was validated using spiked blank tissues as well as antibiotic treated shrimps with enrofloxacin and tetracycline, two antibiotics often found to be used in shrimp production. For tetracyclines and (fluoro)quinolones, the detection capability was below the maximum residue limit (MRL), while it was around the MRL for sulfonamides. The specificity of the microbiological screening was 100% in all cases while the sensitivity and accuracy was 100% in almost all cases. The capacity of the method to detect contaminated samples was confirmed on antibiotic treated shrimps, analyzed in parallel with a confirmatory method (Liquid Chromatography coupled to mass spectrometry (LC-MS)).

  20. Crack Imaging and Quantification in Aluminum Plates with Guided Wave Wavenumber Analysis Methods

    Science.gov (United States)

    Yu, Lingyu; Tian, Zhenhua; Leckey, Cara A. C.

    2015-01-01

    Guided wavefield analysis methods for detection and quantification of crack damage in an aluminum plate are presented in this paper. New wavenumber components created by abrupt wave changes at the structural discontinuity are identified in the frequency-wavenumber spectra. It is shown that the new wavenumbers can be used to detect and characterize the crack dimensions. Two imaging based approaches, filter reconstructed imaging and spatial wavenumber imaging, are used to demonstrate how the cracks can be evaluated with wavenumber analysis. The filter reconstructed imaging is shown to be a rapid method to map the plate and any existing damage, but with less precision in estimating crack dimensions; while the spatial wavenumber imaging provides an intensity image of spatial wavenumber values with enhanced resolution of crack dimensions. These techniques are applied to simulated wavefield data, and the simulation based studies show that spatial wavenumber imaging method is able to distinguish cracks of different severities. Laboratory experimental validation is performed for a single crack case to confirm the methods' capabilities for imaging cracks in plates.

  1. [Butanol extraction combined with dilute hydrochloric acid dissolution-atomic fluorescence spectrometric method for indirect determination of molybdenum in Chinese herbal medicine].

    Science.gov (United States)

    Lu, Jian-Ping; Geng, Guo-Xing; Tang, Yan-Kui; Lu, Zhi-Yong

    2012-12-01

    A method for indirectly determining the molybdenum in Chinese herbal medicine by butanol extraction and dilute hydrochloric acid dissolution was established for atomic fluorescence spectrometry. The molybdoarsenate heteropoly acid, formed in the presence of As(V) and ammonium molybdate in 0.3 mol x L(-1) sulphuric acid medium, was separated and enriched in the organic solvent, then the evaporation of organic reagent was implemented and the left residue was dissolved in dilute hydrochloric acid in which the arsenic content was determined on behalf of molybdenum. In the optimum experimental conditions, molybdenum content in 0-15 microg x L(-1) range depicts a good linear relationship, the detection limit and relative standard deviation of 0.44 microg x L(-1) and 1.1% were obtained, respectively. Spiked Chinese herbal medicine samples were determined with the proposed method, and recoveries of 95.6%-101.3% were achieved.

  2. Developments in variational methods for high performance plate and shell elements

    Science.gov (United States)

    Felippa, Carlos A.; Militello, Carmelo

    1991-01-01

    High performance elements are simple finite elements constructed to deliver engineering accuracy with coarse arbitrary grids. This is part of a series on the variational foundations of high-performance elements, with emphasis on plate and shell elements constructed with the free formulation (FF) and assumed natural strain (ANS) methods. Parameterized variational principles are studied that provide a common foundation for the FF and ANS methods, as well as for a combination of both. From this unified formulation a variant of the ANS formulation, called the assumed natural deviatoric strain (ANDES) formulation, emerges as an important special case. The first ANDES element, a high-performance 9 degrees of freedom triangular Kirchhoff plate bending element, is briefly described to illustrate the use of the new formulation.

  3. Probabilistic fracture investigation of symmetric angle ply laminated composite plates using displacement correlation method

    Directory of Open Access Journals (Sweden)

    Lal Achchhe

    2016-01-01

    Full Text Available The second order statistics of mixed mode stress intensity factors (MSIF of single edge V-notched angle ply laminated composite plate subjected to uniaxial tensile load with uncertinity in the system properties using displacement correlation method (DCM is evaluated. The random system properties such as material properties, crack opening and crack length are modelled as combined uncorrelated and correlated random system variables. A C0 finite element method (FEM based on higher order shear deformation plate theory (HSDT is used for basic formulation. The Taylor series based first order perturbation technique (FOPT, second order perturbation technique (SOPT are used and direct Monte Carlo simulation (MCS is performed to evaluate the statistics (mean and coefficient of variance of the mixed mode SIFs. The present work signifies the accurate analysis of frature behaviour by influence of different random variables and fibre orientations on the fracture behaviour in angle ply laminates.

  4. Homotopy perturbation method for heat transfer flow of a third grade fluid between parallel plates

    Energy Technology Data Exchange (ETDEWEB)

    Siddiqui, A.M. [Pennsylvania State University, York Campus, York, PA 17403 (United States); Zeb, A. [COMSATS Institute of Information Technology, 30 H-8/1, Islamabad (Pakistan)], E-mail: amtaz56@yahoo.co.uk; Ghori, Q.K. [COMSATS Institute of Information Technology, 30 H-8/1, Islamabad (Pakistan); Benharbit, A.M. [Pennsylvania State University, York Campus, York, PA 17403 (United States)

    2008-04-15

    The present paper studies the heat transfer flow of a third grade fluid between two heated parallel plates for the constant viscosity model. Three flow problems, namely plane Couette flow, plane Poiseuille flow and plane Couette-Poiseuille flow have been considered. In each case the non-linear momentum equation and the energy equation have been solved using the homotopy perturbation method. Explicit analytical expressions for the velocity field and the temperature distribution have been derived.

  5. Determination of Rock Mass Modulus Using the Plate Loading Method at Yucca Mountain, Nevada

    Energy Technology Data Exchange (ETDEWEB)

    Finley, R.E.; George, J.T.; Riggins, M.

    1999-08-02

    A suite of plate loading tests has recently been conducted by Sandia National Laboratories at the Exploratory Studies Facility at Yucca Mountain, Nevada. Fielding of these in situ tests as well as other approaches undertaken for the determination of rock mass modulus are described. The various methodologies are evaluated and their data compared. Calculation by existing empirical methods and numerical modeling are compared to each other as well as to field data.

  6. Structural analysis of plate-type fuel assemblies and development of a non-destructive method to assess their integrity

    Energy Technology Data Exchange (ETDEWEB)

    Caresta, Mauro, E-mail: mcaresta@yahoo.it [School of Mechanical and Manufacturing Engineering, The University of New South Wales, Sydney 2052, NSW (Australia); Wassink, David [Australian Nuclear Science and Technology Organisation (ANSTO), Lucas Heights 2234, NSW (Australia)

    2013-09-15

    Highlights: • A plate-type fuel assembly is made of thin plates mounted in a box-like structure. • Drag force from the coolant can shift the plates. • A non invasive method is proposed to test the strength of the plate connections. • The natural frequencies’ shift is used to assess the fuel integrity. -- Abstract: This work is concerned with the structural behaviour and the integrity of parallel plate-type nuclear fuel assemblies. A plate-type assembly consists of several thin plates mounted in a box-like structure and is subjected to a coolant flow that can result in a considerable drag force. A finite element model of an assembly is presented to study the sensitivity of the natural frequencies to the stiffness of the plates’ junctions. It is shown that the shift in the natural frequencies of the torsional modes can be used to check the global integrity of the fuel assembly while the local natural frequencies of the inner plates can be used to estimate the maximum drag force they can resist. Finally a non-destructive method is developed to assess the resistance of the inner plates to bear an applied load. Extensive computational and experimental results are presented to prove the applicability of the method presented.

  7. Effect of different heating methods on deformation of metal plate under upsetting mechanism in laser forming

    Science.gov (United States)

    Shi, Yongjun; Liu, Yancong; Yi, Peng; Hu, Jun

    2012-03-01

    In a laser forming process, different forming mechanisms have different deformation behaviors. The aim of laser forming is to acquire plane strain under an upsetting mechanism, while a plate undergoes a small bending deformation. In some industrial applications, the bending strain should not occur. To achieve high-precision forming, the deformation behaviors of a metal plate when an upsetting mechanism plays a dominant role are studied in the paper. Several heating methods are proposed to reduce the plane strain difference along the thickness direction and little bending deformation resulting from a small temperature difference between the top and bottom surfaces of the plate. The results show that negligible bending deformation and a uniform plastic plane strain field can be obtained by simultaneously heating the top and bottom surfaces with the same process parameters. A conventional scanning method needs a larger spot diameter and slower scanning speed under the upsetting mechanism, but a smaller spot diameter and quicker scanning speed may be selected using the simultaneous heating method, which can greatly widen the potential scope of process parameters.

  8. Comparative detection of bacterial adhesion to Caco-2 cells with ELISA, radioactivity and plate count methods.

    Science.gov (United States)

    Le Blay, Gwenaëlle; Fliss, Ismaïl; Lacroix, Christophe

    2004-11-01

    Different methods are used to study bacterial adhesion to intestinal epithelial cells, which is an important step in pathogenic infection as well as in probiotic colonization of the intestinal tract. The aim of this study was to compare the ELISA-based method with more conventional plate count and radiolabeling methods for bacterial adhesion detection. An ELISA-based assay was optimized for the detection of Bifidobacterium longum and Escherichia coli O157:H7, which are low and highly adherent bacteria, respectively. In agreement with previous investigations, a percentage of adhesion below 1% was obtained for B. longum with ELISA. However, high nonspecific background and low positive signals were measured due to the use of polyclonal antibodies and the low adhesion capacity with this strain. In contrast, the ELISA-based method developed for E. coli adhesion detected a high adhesion percentage (15%). For this bacterium the three methods tested gave similar results for the highest bacterial concentrations (6.8 Log CFU added bacteria/well). However, differences among methods increased with the addition of decreased bacterial concentration due to different detection thresholds (5.9, 5.6 and 2.9 Log CFU adherent bacteria/well for radioactivity, ELISA and plate count methods, respectively). The ELISA-based method was shown to be a good predictor for bacterial adhesion compared to the radiolabeling method when good quality specific antibodies were used. This technique is convenient and allows handling of numerous samples.

  9. An Inverse method of elastic constants for unidirectional fiber-reinforced composite plate

    Institute of Scientific and Technical Information of China (English)

    YANG Jing; CUI Lian-jun; XU Jian; CHENG Jian-chun

    2006-01-01

    An inverse method is presented to determine the elastic constants of an experimental sample,a titanium graphite unidirectional fiber-reinforced composite plate,using wavelet transform and neural networks.Optimal algorithms of wavelet transform and neural networks are given here in order to improve the accuracy of inversion results.Coherent results were shown in both fiber direction and cross fiber direction,proving the feasibility of this method.Neither the group velocity of the Lamb wave modes are needed,as in the conventional method,and no direct least-square fitting of the experimental waveforms is necessary.

  10. A Comprehensive Study of Internal Distraction Plating, an Alternative Method for Distal Radius Fractures

    Science.gov (United States)

    Mavani, Kinjal J

    2016-01-01

    Introduction The management of highly comminuted distal radius fractures still remains a major treatment challenge. Articular comminution and compromised bone quality are the culprits. One novel approach is the technique of Internal Distraction Plating which involves “bridging” the fracture with the use of a standard 3.5mm plate applied dorsally in distraction from the radius, proximal to the fracture, to the long finger metacarpal distally, bypassing the comminuted segment. The plate is removed once fracture union has been achieved. Aim The present study was conducted with the aim to evaluate the role of internal dorsal distraction plating as an alternative method in the treatment of fracture distal radius in terms of special indications, technique and outcome. Materials and Methods This study was a prospective longitudinal study on 20 patients (mean age 62 years) treated with internal distraction plating for comminuted distal radius fractures with specific indications. Regular follow-ups with standard radiographs and analysis were done upto 24 months. Functional outcome were assessed by DASH Score and the Gartland and Werley demerit score. Results At final follow-up, all fractures had united and X-rays showed mean palmar tilt of 7°, positive ulnar variance of 0.5mm, radial inclination of 18° and average loss of 2mm of radial height. Mean range of motion values for wrist flexion 46°, extension 50°, pronation 79° and supination 77° At final follow-up, the mean DASH score was 32. 85% patient had excellent to good result as per Gartland and Werley demerit score. This construct has yield satisfactory clinical and radiographic results with these very challenging injuries. Conclusion The purpose of this study was to report the radiographic and the functional outcomes of treatment with this technique. External fixator and volar plating in communited distal end radius fractures are not always satisfactory in old age with osteoporotic bone because of

  11. Microscopic studies of the influence of main exposure time on parameters of flexographic printing plate produced by digital thermal method.

    Science.gov (United States)

    Harri, Liliya

    2009-10-01

    The digital thermal technology of producing flexographic printing plates from photopolymer plates is one of the newest technologies. This technology allows to develop flexographic plates without the use of any solvent. The process of producing flexographic printing plates by the digital thermal method consists of several main stages: back exposure, laser exposure, main exposure, thermal development, post exposure, and light finishing. The studies carried out with the use of optical stereoscopic microscopy allowed to determine the effect of time of main exposure to ultraviolet radiation on the dot area, diameter, and edge factor of halftone dots reproduced on flexographic printing plate produced by the digital thermal method, as well as on the quality of reproducing the surface and on the profiles of free-standing printing microelements. The results of the microscopic studies performed have allowed to define the criteria of establishing optimum time of main exposure of photopolymer plates used in the digital thermal technology of producing flexographic printing plates. A precise definition of the criteria for determining the optimum time of main exposure will enable to reduce the time-consuming control tests and to eliminate errors in both the process of manufacturing flexographic printing plates and in the printing process carried out with the use of such plates.

  12. Dilution Methods in Flow Injection Analysis. Evaluation of Different Approaches as Exemplified for the Determination of Nitrosyl in Concentrated Sulphuric Acid

    DEFF Research Database (Denmark)

    Jørgensen, Ulla Vang; Nielsen, Steffen; Hansen, Elo Harald

    1998-01-01

    Instigated by developing a flow injection procedure for assay of nitrosyl in concentrated sulphuric acid, different approaches for reliable and robust on-line dilution in FIA were evaluated. These comprised the application of mixing tees in conjunction with mixing coils (including knotted reactors...... approach the criteria stipulated were that the procedure should allow a dilution factor of approximately 100, yet without excessive zone spreading, so that it, on one hand, effectively could eliminate the pronounced Schlieren effect encountered when mixing concentrated sulphuric acid with an aqueous...... in conjunction with knotted reactors of relatively large internal diameter (1.5 mm). The optimized FI-manifold was used with the Griess method for the spectrophotometric assay of nitrosyl (nitrite) in standards prepared in the matrix of concentrated sulphuric acid (detection limit 0.16 mg/l NO+-N (3s...

  13. Calculation method of composite foundation sedimentation of grouting pile with cover plate under embankment load

    Institute of Scientific and Technical Information of China (English)

    顾长存; 洪昌地; 马文彬; 李雪平

    2008-01-01

    Grouting pile is a new soft soil foundation treatment method with characteristics such as no vibration, no noise, no soil compaction, light construction machines and quick construction velocity and so on. At present, study on reinforcement mechanism and design calculation method of composite foundation of grouting pile is initially started without design specifications, so it is usually required to draw on design specifications of stump pile when designing composite foundation of grouting pile while grouting pile has its characteristics and difference although reinforcement mechanisms and construction processes of two types of piles are similar. Sedimentation formula of composite foundation of grouting pile with cover plate is educed and a suitable deformation mode is proposed by aiming to deformation characteristics of composite foundation of grouting pile with cover plate under embankment load on basis of relevant sedimentation theories of composite foundation by combination of characteristics of composite foundation of grouting pile. The sedimentation calculation formula of grouting pile with cover plate under embankment load is educed according to balance relation of force and displacement coordination conditions by elastic theory and sedimentation calculation model established is validated by sedimentation monitoring documents of one expressway in China.

  14. Stochastic finite element method for random harmonic analysis of composite plates with uncertain modal damping parameters

    Science.gov (United States)

    Sepahvand, K.

    2017-07-01

    Damping parameters of fiber-reinforced composite possess significant uncertainty due to the structural complexity of such materials. Considering the parameters as random variables, this paper uses the generalized polynomial chaos (gPC) expansion to capture the uncertainty in the damping and frequency response function of composite plate structures. A spectral stochastic finite element formulation for damped vibration analysis of laminate plates is employed. Experimental modal data for samples of plates is used to identify and realize the range and probability distributions of uncertain damping parameters. The constructed gPC expansions for the uncertain parameters are used as inputs to a deterministic finite element model to realize random frequency responses on a few numbers of collocation points generated in random space. The realizations then are employed to estimate the unknown deterministic functions of the gPC expansion approximating the responses. Employing modal superposition method to solve harmonic analysis problem yields an efficient sparse gPC expansion representing the responses. The results show while the responses are influenced by the damping uncertainties at the mid and high frequency ranges, the impact in low frequency modes can be safely ignored. Utilizing a few random collocation points, the method indicates also a very good agreement compared to the sampling-based Monte Carlo simulations with large number of realizations. As the deterministic finite element model serves as black-box solver, the procedure can be efficiently adopted to complex structural systems with uncertain parameters in terms of computational time.

  15. -ree vibration analysis of cracked thin plates by quasi-convex coupled isogeometric-meshfree method

    Institute of Scientific and Technical Information of China (English)

    Hanjie ZHANG[1,2; JunzhaoWU[1,2; Dongdong WANG[1,2

    2015-01-01

    The free vibration analysis of cracked thin plates via a quasi-convex coupled isogeometric-meshfree method is presented. This formulation employs the consistently coupled isogeometric-meshfree strategy where a mixed basis vector of the convex B-splines is used to impose the consistency conditions throughout the whole problem domain. Meanwhile, the rigid body modes related to the mixed basis vector and reproducing conditions are also discussed. The mixed basis vector simultaneously offers the consistent isogeometric-meshfree coupling in the coupled region and the quasi-convex property for the meshfree shape functions in the meshfree region, which is particularly attractive for the vibration analysis. The quasi-convex meshfree shape functions mimic the isogeometric basis function as well as offer the meshfree nodal arrangement flexibility. Subsequently, this approach is exploited to study the free vibration analysis of cracked plates, in which the plate geometry is exactly represented by the isogeometric basis functions, while the cracks are discretized by meshfree nodes and highly smoothing approximation is invoked in the rest of the problem domain. The efficacy of the present method is illustrated through several numerical examples.

  16. A Sandwich Method Using Kapandji Intrafocal Pinning to Facilitate Palmar Plating of Displaced Distal Radius Fractures.

    Science.gov (United States)

    Huang, Hui-Kuang; Huang, Yi-Chao; Wang, Jung-Pan; Chang, Ming-Chau

    2017-09-01

    The use of palmar plating in the treatment of dorsally displaced distal radius fracture is very common, and can result in a good functional outcome. We present an easy "sandwich method" to reduce the fracture and to facilitate osteosynthesis. Firstly, the dorsal Kapandji intrafocal wire was applied to achieve the reduction of the dorsally displaced fracture and provide a volar-directed force. Then the intra-articular fractures were reduced or the metaphyseal defect is stuffed with bone graft if necessary. Finally, the anatomical plate is used to buttress and push back the distal fragment to complete the osteosynthesis. The postoperative radiographic parameters, comparing with the contralateral noninjured side, could achieve similar radial height, radial inclination, volar tilt, and ulnar variance without significant difference.

  17. Modelling Thermal Shock in Functionally Graded Plates with Finite Element Method

    Directory of Open Access Journals (Sweden)

    Vyacheslav N. Burlayenko

    2016-01-01

    Full Text Available Thermomechanical behavior and crack propagation in a functionally graded metal/ceramic plate undergoing thermal shock are analyzed by using the finite element method. A two-dimensional plane strain functionally graded finite element has been developed within the ABAQUS software environment for this purpose. An actual material gradation has been accomplished by sampling material quantities directly at the Gauss points of the element via programming appropriate user-defined subroutines. The virtual crack closure technique is used to model a crack growth under thermal loading. Contact possible between crack lips during the crack advance is taken into account in thermomechanical simulations as well. The paper shows that the presented finite element model can be applied to provide an insight into the thermomechanical respond and failure of the metal/ceramic plate.

  18. An Unstructured Finite Volume Method for Impact Dynamics of a Thin Plate

    Institute of Scientific and Technical Information of China (English)

    Weidong Chen; Yanchun Yu

    2012-01-01

    The examination of an unstructured finite volume method for structural dynamics is assessed for simulations of systematic impact dynamics.A robust display dual-time stepping method is utilized to obtain time accurate solutions.The study of impact dynamics is a complex problem that should consider strength models and state equations to describe the mechanical behavior of materials.The current method has several features.1) Discrete equations of unstructured finite volume method naturally follow the conservation law.2)Display dual-time stepping method is suitable for the analysis of impact dynamic problems of time accurate solutions.3) The method did not produce grid distortion when large deformation appeared.The method is validated by the problem of impact dynamics of an elastic plate with initial conditions and material properties.The results validate the finite element numerical data.

  19. Evaluation of the petrifilm plate method for the enumeration of aerobic microorganisms and coliforms in retailed meat samples.

    Science.gov (United States)

    Park, Y H; Seo, K S; Ahn, J S; Yoo, H S; Kim, S P

    2001-11-01

    This study was designed to compare the effectiveness and applicability of the Petrifilm plate method with the Association of Official Analytical Chemists' (AOAC) standard aerobic count method and violet red bile agar method for meat products. The comparison was carried out using 303 meat samples collected from various retailers: 110 pork samples, 87 chicken samples, and 107 beef samples. In the comparison of the correlation coefficient (R) between the conventional method and the Petrifilm plate method by a linear regression analysis, the correlation coefficient in total microorganisms was 0.99, 0.95, and 0.94 in pork, beef, and chicken samples, respectively. The correlation coefficient in coliform count was 0.83, 0.96, and 0.81 in pork, beef, and chicken samples, respectively. Based on the high correlation in the total microorganism count, it might be possible to replace the conventional methods with the Petrifilm plate method. For coliform counts, the Petrifilm plate method also showed a generally high correlation coefficient, except for pork samples, which are more subject to contamination. The Petrifilm plate method was simpler and less time-consuming in sample preparation and, in procedures, faster than the conventional method. These results suggested that the 3M Petrifilm plate method could replace the conventional methods in the analysis of microorganism contamination measurement in meat products.

  20. Evaluation of the SimPlate method for enumeration of Escherichia coli in swab samples from beef and lamb carcasses.

    Science.gov (United States)

    Hauge, Sigrun J; Nesbakken, Truls; Skjerve, Eystein; Dommarsnes, Kari; Østensvik, Øyvin

    2010-08-15

    Abattoirs have to enumerate Escherichia coli on carcass surfaces as part of compulsory HACCP monitoring and they therefore need rapid and reliable methods. The objective of this study was to compare a conventional plating method with a faster, simpler method for detection and enumeration of E. coli in samples from naturally contaminated carcasses. The two methods were the conventional pour plate method of the Nordic Committee on Food Analysis; NMKL Method No. 125, and the enzymatic method of SimPlate Coliforms &E. coli. Materials were 588 cotton-cloth samples used for swabbing 100 cm(2) areas on four sites on cattle and lamb carcasses in three commercial abattoirs in Norway. E. coli was detected by at least one of the methods in 270 (46%) of the samples. Forty-five samples (8%) were positive only by SimPlate while 28 samples (5%) were positive only by NMKL125. Cohen's kappa value was 0.74 for detection/non-detection results, which showed a high level of agreement between the two methods. E. coli counts determined by the conventional NMKL125 method showed a high concordance correlation (ccc 0.80, slope 0.99) with most probable number (MPN) values obtained with SimPlate. SimPlate is a rapid and reliable method for detection and enumeration of E. coli and a suitable alternative method for use with swab samples from cattle and lamb carcasses.

  1. Study on Interaction Between Two Parallel Plates with Iteration Method in Functional Theory

    Institute of Scientific and Technical Information of China (English)

    Ming Zhou; Zheng-wu Wang; Zu-min Xu

    2008-01-01

    By introducing the functional theory into the calculation of electric double layer (EDL) interaction,the interaction energies of two parallel plates were calculated respectively at low,moderate,and high potentials. Compared with the results of two existing methods,Debye-Hiickel and Langmuir methods,which are appli- cable just to the critical potentials and perform poorly in the intermediate potential,the functional approach not only has much simpler expression of the EDL interaction energy,but also performs well in the entire range of potentials.

  2. Diagnosis of pertussis in vaccinated children of Khairpur, Sindh, Pakistan by Cough Plate Method

    Directory of Open Access Journals (Sweden)

    Syed Habib Bukhari

    2011-09-01

    Full Text Available Objectives: Pertussis or whooping cough is a communicable infection of upper respiratory tract that mainly affects children. Reports regarding resurgence of pertussis in vaccinated children mainly motivated us to document pertussis in the children. The aim of the study was to explore pertussis in vaccinated children using an alternative method for pertussis diagnosis.Materials and methods: A total of 700 clinical samples were collected during study period (2006-2009, from suspected whooping cough cases of Diphtheria-tetanus- whole cell pertussis (DTwP vaccinated children both male and female aged from 6 months to 84 months The classical ‘Cough Plate Method’ instead of Nasopharyngeal Swab was used for sampling to find out its potential in diagnosis of pertussis.Results: Present study reports the presence of pertussis in vaccinated children using Cough Plate Method. The method successfully isolated Bordetella pertussis from suspected patients of pertussis. A total of 28 culture confirmed cases were detected among 700 samples tested. (Total Isolation rate: 4%.The peak incidence age under risk was 48 months. However, pertussis was detected in children aged as young as 6 and 12 months.Conclusion: The ‘Cough plate’ method used for isolation proved successful and simple instead of nasopharyngeal swabs that is difficult to perform and children may be reluctant to this sampling method when tried. J Microbiol Infect Dis 2011;1 (2 : 68-72

  3. Standard Test Method for Mechanical Hydrogen Embrittlement Evaluation of Plating/Coating Processes and Service Environments

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2010-01-01

    1.1 This test method describes mechanical test methods and defines acceptance criteria for coating and plating processes that can cause hydrogen embrittlement in steels. Subsequent exposure to chemicals encountered in service environments, such as fluids, cleaning treatments or maintenance chemicals that come in contact with the plated/coated or bare surface of the steel, can also be evaluated. 1.2 This test method is not intended to measure the relative susceptibility of different steels. The relative susceptibility of different materials to hydrogen embrittlement may be determined in accordance with Test Method F1459 and Test Method F1624. 1.3 This test method specifies the use of air melted AISI E4340 steel per SAE AMS-S-5000 (formerly MIL-S-5000) heat treated to 260 – 280 ksi (pounds per square inch x 1000) as the baseline. This combination of alloy and heat treat level has been used for many years and a large database has been accumulated in the aerospace industry on its specific response to exposure...

  4. Direct Preparation of Strontium Aluminate Phosphor Plate by Reactive Infiltration Method

    Energy Technology Data Exchange (ETDEWEB)

    Watari, T [Ceramic Research Laboratory, Graduate School of Science and Engineering, Saga University, 1 Honjo, Saga 840-8502 (Japan); Ikeue, K; Torikai, T; Yada, M, E-mail: watarit@cc.saga-u.ac.jp [Graduate School of Science and Engineering, Saga University, 1 Hojo, Saga 840-8502 (Japan)

    2011-05-15

    Sr-aluminate phosphor plates were prepared by the infiltration-reaction method. The mixture of SrCO{sub 3}, Eu{sub 2}O{sub 3}, Dy{sub 2}O{sub 3} powders were mixed and coated on the porous alumina plate, followed by heating at 1300deg. C for 4h under 10%H{sub 2}+90%N{sub 2} gas atmosphere. After processing, the surface part of the Al{sub 2}O{sub 3} plate became dense, {approx}20{mu}m thickness. SrAl{sub 2}O{sub 4} and Sr{sub 3}Al{sub 2}O{sub 6} phases were observed as the product. The coated mixture powder changed to a liquid state and infiltrated into the pores of the alumina plate. During processing, the following reactions occurred; SrCO{sub 3{yields}}SrO+CO{sub 2}, SrO+Al{sub 2}O{sub 3{yields}}SrAl{sub 2}O{sub 4}, 3SrO+Al{sub 2}O{sub 3{yields}}Sr{sub 3}Al{sub 2}O{sub 6}. According to the Sr distribution analysis at the dense layer, Sr{sub 3}Al{sub 2}O{sub 6} and SrAl{sub 2}O{sub 4} phases were mainly formed in the surface-side and Al{sub 2}O{sub 3}-side layers, respectively. This plate emits green luminescence by the irradiation of the 'black-light'. The wave length of the emitted light was in the range of 450-650nm, and the maximum intensity appeared at 520nm. Also, this plate showed green afterglow. The best mixing ratio was Sr/Eu/Dy = 5/1/1. This afterglow intensity decreased from 0.14cdm{sup -2} (0sec.) to 0.01cdm{sup -2} (30sec.). We observed the green afterglow for 3 hours in the dark.

  5. Depth compensating calculation method of computer-generated holograms using symmetry and similarity of zone plates

    Science.gov (United States)

    Wei, Hui; Gong, Guanghong; Li, Ni

    2017-10-01

    Computer-generated hologram (CGH) is a promising 3D display technology while it is challenged by heavy computation load and vast memory requirement. To solve these problems, a depth compensating CGH calculation method based on symmetry and similarity of zone plates is proposed and implemented on graphics processing unit (GPU). An improved LUT method is put forward to compute the distances between object points and hologram pixels in the XY direction. The concept of depth compensating factor is defined and used for calculating the holograms of points with different depth positions instead of layer-based methods. The proposed method is suitable for arbitrary sampling objects with lower memory usage and higher computational efficiency compared to other CGH methods. The effectiveness of the proposed method is validated by numerical and optical experiments.

  6. A simple method to definethe heat conductivity of a limited plate

    Directory of Open Access Journals (Sweden)

    Evdokimov Andrey Sergeevich

    2014-02-01

    Full Text Available To the present moment there are a lot of ways to define heat conductivity and thermal diffusivity of solid bodies. The schemes of determining heat conductivity, which use transient methods, usually include a heater and a cooler. The sample is placed in between them. The temperature and temperature differential is determined using several thermocouples.The authors present a method of determining the thermal characteristics of a sample in the form of a rectangular plate, allowing to apply only one thermocouple, which leads to a simple analytical expression for thermal diffusivity. The described method provides high-precision determination of thermal diffusivity of the body of small size and with the accuracy sufficient for practice — conductivity coefficient. The method uses a simple mathematical model and minimal hardware resources compared to other methods. The exception is the heat-insulating materials. The determination of their thermal conductivity using this method can lead to poor accuracy.

  7. Error compensation of thin plate-shape part with prebending method in face milling

    Science.gov (United States)

    Yi, Wei; Jiang, Zhaoliang; Shao, Weixian; Han, Xiangcheng; Liu, Wenping

    2015-01-01

    Low weight and good toughness thin plate parts are widely used in modern industry, but its flexibility seriously impacts the machinability. Plenty of studies focus on the influence of machine tool and cutting tool on the machining errors. However, few researches focus on compensating machining errors through the fixture. In order to improve the machining accuracy of thin plate-shape part in face milling, this paper presents a novel method for compensating the surface errors by prebending the workpiece during the milling process. First, a machining error prediction model using finite element method is formulated, which simplifies the contacts between the workpiece and fixture with spring constraints. Milling forces calculated by the micro-unit cutting force model are loaded on the error prediction model to predict the machining error. The error prediction results are substituted into the given formulas to obtain the prebending clamping forces and clamping positions. Consequently, the workpiece is prebent in terms of the calculated clamping forces and positions during the face milling operation to reduce the machining error. Finally, simulation and experimental tests are carried out to validate the correctness and efficiency of the proposed error compensation method. The experimental measured flatness results show that the flatness improves by approximately 30 percent through this error compensation method. The proposed method not only predicts the machining errors in face milling thin plate-shape parts but also reduces the machining errors by taking full advantage of the workpiece prebending caused by fixture, meanwhile, it provides a novel idea and theoretical basis for reducing milling errors and improving the milling accuracy.

  8. Error Compensation of Thin Plate-shape Part with Prebending Method in Face Milling

    Institute of Scientific and Technical Information of China (English)

    YI Wei; JIANG Zhaoliang; SHAO Weixian; HAN Xiangcheng; LIU Wenping

    2015-01-01

    Low weight and good toughness thin plate parts are widely used in modern industry, but its flexibility seriously impacts the machinability. Plenty of studies focus on the influence of machine tool and cutting tool on the machining errors. However, few researches focus on compensating machining errors through the fixture. In order to improve the machining accuracy of thin plate-shape part in face milling, this paper presents a novel method for compensating the surface errors by prebending the workpiece during the milling process. First, a machining error prediction model using finite element method is formulated, which simplifies the contacts between the workpiece and fixture with spring constraints. Milling forces calculated by the micro-unit cutting force model are loaded on the error prediction model to predict the machining error. The error prediction results are substituted into the given formulas to obtain the prebending clamping forces and clamping positions. Consequently, the workpiece is prebent in terms of the calculated clamping forces and positions during the face milling operation to reduce the machining error. Finally, simulation and experimental tests are carried out to validate the correctness and efficiency of the proposed error compensation method. The experimental measured flatness results show that the flatness improves by approximately 30 percent through this error compensation method. The proposed method not only predicts the machining errors in face milling thin plate-shape parts but also reduces the machining errors by taking full advantage of the workpiece prebending caused by fixture, meanwhile, it provides a novel idea and theoretical basis for reducing milling errors and improving the milling accuracy.

  9. The analysis of the accuracy of the wheel alignment inspection method on the side-slip plate stand

    Science.gov (United States)

    Gajek, A.; Strzępek, P.

    2016-09-01

    The article presents the theoretical basis and the results of the examination of the wheel alignment inspection method on the slide slip plate stand. It is obligatory test during periodic technical inspection of the vehicle. The measurement is executed in the dynamic conditions. The dependence between the lateral displacement of the plate and toe-in of the tested wheels has been shown. If the diameter of the wheel rim is known then the value of the toe-in can be calculated. The comparison of the toe-in measurements on the plate stand and on the four heads device for the wheel alignment inspection has been carried out. The accuracy of the measurements and the influence of the conditions of the tests on the plate stand (the way of passing through the plate) were estimated. The conclusions about the accuracy of this method are presented.

  10. Damage Detection of Closed Crack in a Metallic Plate Using Nonlinear Ultrasonic Time Reversal Method

    Directory of Open Access Journals (Sweden)

    Wang Zhang

    2013-01-01

    Full Text Available Initial cracks in metallic structures incline to be closed at rest. Such incipient damage generally fails to be detected and located with traditional linear ultrasonic techniques because ultrasonic waves penetrate the contact area of the closed crack. In this paper, an imaging algorithm based on nonlinear ultrasonic time reversal method is proposed to detect closed cracks in aluminum plates. Two surface-bonded piezoelectric transducer arrays are used to generate, receive, and reemit ultrasonic wave signals. The closed crack is simulated by tightening a bolt on the aluminum plate. By applying large amplitude excitation voltage on the PZT transducers, the closed crack could be opened and closed. The transmitted waves recorded by PZT array contain nonlinear components, the signals are time reversed and emitted back, and the tone burst reconstructions are achieved. The linear reciprocity and the time reversibility break down due to the presence of the nonlinear components. The correlation coefficient between the original excitation signal and the reconstructed signal is calculated to define the damage index for individual sensing path and is used to develop an imaging algorithm to locate the closed crack on the plate. The experimental results demonstrate that incident wave signals and their reconstructed signals can be used to accurately detect and locate closed cracks.

  11. Apparatus and method for explosive bonding to edge of flyer plate

    Science.gov (United States)

    Bement, Laurence J.; Kushnick, Anne C.

    1991-09-01

    The invention is an apparatus and a process for the explosive joining of a flyer plate and a base plate. The apparatus consists of a flyer plate positioned over a base plate. The flyer plate has a notch containing a filler material in intimate contact with the flyer plate. An adhesive means holds a ribbon explosive partially overlapping the notch in the flyer plate. A detonating means initiates the ribbon explosive that drives the flyer plate to accomplish a high velocity, angular collision between the mating surfaces. This collision creates surface melts and effacing bonding, resulting in electron sharing linkups between the plates. An unbonded tab fractures at a base of the notch leaving a bond to an edge of the attached flyer plate.

  12. 3M Petrifilm enterobacteriaceae count plate method for enumeration of enterobacteriaceae in selected foods: collaborative study.

    Science.gov (United States)

    Silbernagel, Karen M; Lindberg, Kathryn G

    2003-01-01

    The practice of detecting and enumerating all oxidase-negative, glucose-fermenting-Gram-negative rods (i.e., the family Enterobacteriaceae) is used to indicate unsanitary or inadequate food processing conditions. The objective of this interlaboratory collaborative study was to evaluate and compare the methods described in Standard Methods for the Examination of Dairy Products (SMEDP) and the Compendium of Methods for the Microbiological Examination of Foods (Compendium) with a commercial product, the 3M Petrifilm Enterobacteriaceae Count Plate, for the recovery of Enterobacteriaceae in foods. Six foods--cheddar cheese, milk, flour, frozen prepared meals, frozen broccoli, and nut pieces--were analyzed for Enterobacteriaceae by 12 collaborating laboratories. For each food tested, the collaborators received 8 blind test portions consisting of a control test portion and 3 levels of inoculated test portion, each in duplicate. Each test portion was tested by the Petrifilm Enterobacteriaceae Count Plate method as well as the SMEDP or Compendium methods. The precision estimates (repeatability or within-laboratory variation, and reproducibility or between-laboratory variation) were calculated with standard statistical techniques.

  13. Application of the quadrilateral area coordinate method: a new element for laminated composite plate bending problems

    Institute of Scientific and Technical Information of China (English)

    Song Cen; Xiangrong Fu; Yuqiu Long; Hongguang Li; Zhenhan Yao

    2007-01-01

    Recently, some new quadrilateral finite elements were successfully developed by the Quadrilateral Area Coordinate (QAC) method. Compared with those traditional models using isoparametric coordinates, these new models are less sensitive to mesh distortion. In this paper, a new displacement-based, 4-node 20-DOF (5-DOF per node)quadrilateral bending element based on the first-order shear deformation theory for analysis of arbitrary laminated composite plates is presented. Its bending part is based on the element AC-MQ4, a recent-developed high-performance Mindlin-Reissner plate element formulated by QAC method and the generalized conforming condition method; and its in-plane displacement fields are interpolated by bilinear shape functions in isoparametric coordinates. Furthermore,the hybrid post-processing procedure, which was firstly proposed by the authors, is employed again to improve the stress solutions, especially for the transverse shear stresses. The resulting element, denoted as AC-MQ4-LC, exhibits excellent performance in all linear static and dynamic numerical examples. It demonstrates again that the QAC method, the generalized conforming condition method, and the hybrid post-processing procedure are efficient tools for developing simple, effective and reliable finite element models.

  14. Investigation of the thermodynamic properties and phase transitions in a strongly diluted three-vertex antiferromagnetic Potts model by the Monte Carlo method

    Science.gov (United States)

    Murtazaev, A. K.; Babaev, A. B.; Ataeva, G. Ya.

    2017-01-01

    The thermodynamic properties and phase transitions in a two-dimensional strongly diluted threevertex antiferromagnetic Potts model on a triangular lattice have been investigated using the Monte Carlo method. The systems with linear dimensions of L × L = N, where L = 18-48, have been considered. It has been shown using the method of fourth-order Binder cumulants that, upon the introduction of nonmagnetic impurities into the spin system described by the two-dimensional antiferromagnetic Potts model, the firstorder phase transition changes to a second-order phase transition.

  15. Extended layerwise method for laminated composite plates with multiple delaminations and transverse cracks

    Science.gov (United States)

    Li, D. H.; Zhang, X.; Sze, K. Y.; Liu, Y.

    2016-10-01

    In this paper, the extended layerwise method (XLWM), which was developed for laminated composite beams with multiple delaminations and transverse cracks (Li et al. in Int J Numer Methods Eng 101:407-434, 2015), is extended to laminated composite plates. The strong and weak discontinuous functions along the thickness direction are adopted to simulate multiple delaminations and interlaminar interfaces, respectively, whilst transverse cracks are modeled by the extended finite element method (XFEM). The interaction integral method and maximum circumferential tensile criterion are used to calculate the stress intensity factor (SIF) and crack growth angle, respectively. The XLWM for laminated composite plates can accurately predicts the displacement and stress fields near the crack tips and delamination fronts. The thickness distribution of SIF and thus the crack growth angles in different layers can be obtained. These information cannot be predicted by using other existing shell elements enriched by XFEM. Several numerical examples are studied to demonstrate the capabilities of the XLWM in static response analyses, SIF calculations and crack growth predictions.

  16. ON MORTAR-TYPE TRUNC ELEMENT METHOD FOR PLATE BENDING PROBOEM

    Institute of Scientific and Technical Information of China (English)

    刘庆; 李立康

    2002-01-01

    Wepresnet a brief introduction of applying the idea of mortar method to locally non-conforming TRUNC element for solving plate bending problem. At the interfaces, three mortarconditions, one for the value of solution in pointwise way, the other two for the normal and tan-gential derivatives of the solution in projection way, are provided to secure the global conver-gence. A fte some detailed analysis, we obtain that its error estimates in both energy norm and dis-crete H1 norm are optimal for u* ∈ H3 (Ω)∩ H20(Ω).

  17. The overlapping plates method applied to CCD observations of 243 Ida

    Science.gov (United States)

    Owen, W. M., Jr.; Yeomans, D. K.

    1994-01-01

    The overlapping plates method has been applied to crossing-point Charge Coupled Device (CCD) observations of minor planet 243 Ida to produce absolute position measurements precise to better than 0.1 sec and differential position measurements precise to better than 0.06 sec. Although these observations numbered only 17 out of the 520 that produced the final ground-based Ida ephemeris for the Galileo spacecraft flyby, their inclusion decreased Ida's downtrack error from 78 to 60 km and its out-of-plane error from 58 to 44 km.

  18. Polarization characterization of PZT disks and of embedded PZT plates by thermal wave methods

    Energy Technology Data Exchange (ETDEWEB)

    Eydam, Agnes, E-mail: Agnes.Eydam@tu-dresden.de; Suchaneck, Gunnar, E-mail: Agnes.Eydam@tu-dresden.de; Gerlach, Gerald [Technische Universität Dresden, Solid State Electronics Laboratory, Helmholtzstraße 18, 01062 Dresden (Germany); Esslinger, Sophia; Schönecker, Andreas; Neumeister, Peter [Fraunhofer Institute for Ceramic Technologies and Systems, Winterbergstraße 28, 01277 Dresden (Germany)

    2014-11-05

    In this work, the thermal wave method was applied to characterize PZT disks and embedded PZT plates with regard to the polarization magnitude and spatial homogeneity. The samples were exposed to periodic heating by means of a laser beam and the pyroelectric response was determined. Thermal relaxation times (single time constants or distributions of time constants) describe the heat losses of the PZT samples to the environment. The resulting pyroelectric current spectrum was fitted to the superposition of thermal relaxation processes. The pyroelectric coefficient gives insight in the polarization distribution. For PZT disks, the polarization distribution in the surface region showed a characteristic decrease towards the electrodes.

  19. A SIMILARITY METHOD FOR LAMINAR WAKE OF POWER-LAW FLUID FLOW AROUND A FLAT PLATE

    Institute of Scientific and Technical Information of China (English)

    Liu Cun-fang; Wang Mei-xia

    2003-01-01

    Based on the characteristic equation for power-law fluid and the Prandtl boundary layer equation, using the similarity method similar to that of Newtonian fluids, two similarity variables were given and a normal differential equation was derived for the laminar wake of power-law fluid flow produced by a flat plate. And numerical results were obtained. The results show that the power-law index n has evident influence on the velocity distribution in the wake. In the wake, velocity gradient is larger, and the wake is narrower for larger n.

  20. Using the heat flow plate method for determining thermal conductivity of building materials

    Science.gov (United States)

    Flori, M.; Puţan, V.; Vîlceanu, L.

    2017-01-01

    The heat flow plate method is used to determine thermal conductivity of a building material sample made of Rohacell (insulating foam). Experimental technique consists in placing the sample with a reference material on top (polystyrene sample) in a calorimetric chamber and heating from underside. Considering that the heat flux which passes through the two layers is constant and knowing thermal conductivity of the reference material, the sample thermal conductivity is determined. The temperature difference between the two opposite sample’s sides is recorded only when the steady state is achieved (constant heat flux).

  1. Predicting method of local damage in reinforced concrete plate with absorber sandwiched between two concrete panels under hard projectile impact

    Energy Technology Data Exchange (ETDEWEB)

    Shirai, Tetsuo; Kambayashi, Atsushi; Ueda, Masatoshi [Takenaka Corp., Osaka (Japan); Ohno, Tomonori; Ishikawa, Nobutaka

    1995-07-01

    The predicting method of local damage in reinforced concrete plate with absorber sandwiched between two concrete panels (double-layered RC plate) under the impact of hard projectile is studied in this paper. The results of high-velocity impact tests to investigate the impact resistance of double-layered RC plates are reported. To evaluate quantitatively the extent of local damage, the existing formulae and the alternative predicting formulae with the multivariate analysis presented here are employed. The prediction of the proposed formulae can agree reasonably well with the actual observed damage, thus can be a useful method in impact resistant design. (author).

  2. Numerical manifold method for the forced vibration of thin plates during bending.

    Science.gov (United States)

    Jun, Ding; Song, Chen; Wei-Bin, Wen; Shao-Ming, Luo; Xia, Huang

    2014-01-01

    A novel numerical manifold method was derived from the cubic B-spline basis function. The new interpolation function is characterized by high-order coordination at the boundary of a manifold element. The linear elastic-dynamic equation used to solve the bending vibration of thin plates was derived according to the principle of minimum instantaneous potential energy. The method for the initialization of the dynamic equation and its solution process were provided. Moreover, the analysis showed that the calculated stiffness matrix exhibited favorable performance. Numerical results showed that the generalized degrees of freedom were significantly fewer and that the calculation accuracy was higher for the manifold method than for the conventional finite element method.

  3. Numerical Manifold Method for the Forced Vibration of Thin Plates during Bending

    Directory of Open Access Journals (Sweden)

    Ding Jun

    2014-01-01

    Full Text Available A novel numerical manifold method was derived from the cubic B-spline basis function. The new interpolation function is characterized by high-order coordination at the boundary of a manifold element. The linear elastic-dynamic equation used to solve the bending vibration of thin plates was derived according to the principle of minimum instantaneous potential energy. The method for the initialization of the dynamic equation and its solution process were provided. Moreover, the analysis showed that the calculated stiffness matrix exhibited favorable performance. Numerical results showed that the generalized degrees of freedom were significantly fewer and that the calculation accuracy was higher for the manifold method than for the conventional finite element method.

  4. Robust scatter correction method for cone-beam CT using an interlacing-slit plate

    CERN Document Server

    Huang, Kuidong; Zhang, Dinghua; Zhang, Hua; Shi, Wenlong

    2015-01-01

    Cone-beam computed tomography (CBCT) has been widely used in medical imaging and industrial nondestructive testing, but the presence of scattered radiation will cause significant reduction of image quality. In this article, a robust scatter correction method for CBCT using an interlacing-slit plate (ISP) is carried out for convenient practice. Firstly, a Gaussian filtering method is proposed to compensate the missing data of the inner scatter image, and simultaneously avoid too-large values of calculated inner scatter and smooth the inner scatter field. Secondly, an interlacing-slit scan without detector gain correction is carried out to enhance the practicality and convenience of the scatter correction method. Finally, a denoising step for scatter-corrected projection images is added in the process flow to control the noise amplification. The experimental results show that the improved method can not only make the scatter correction more robust and convenient, but also achieve a good quality of scatter-corre...

  5. MODIFIED LAYER REMOVAL METHOD FOR MEASUREMENT OF RESIDUAL STRESS DISTRIBUTION IN THICK PRE-STRETCHED ALUMINUM PLATE

    Institute of Scientific and Technical Information of China (English)

    WANGShu-hong; ZUODun-wen; WANGMin; WANGZong-rong

    2004-01-01

    The integrated structure parts are widely used in aircraft. The distortion caused by residual stresses in thick pre-stretched aluminum plates during machining integrated parts is a common and serious problem. To predict and control the machining distortion, the residual stress distribution in the thick plate must be measured firstly. The modified removal method for measuring residual stress in thick pre-stretched aluminum plates is proposed and the stress-strain relation matrix is deduced by elasticity theory. The residual stress distribution in specimen of 7050T7451 plate is measured by using the method, and measurement results are analyzed and compared with data obtained by other methods. The method is effective to measure the residual stress.

  6. RESEARCH ON THE COMPANION SOLUTION FOR A THIN PLATE IN THE MESHLESS LOCAL BOUNDARY INTEGRAL EQUATION METHOD

    Institute of Scientific and Technical Information of China (English)

    龙述尧; 熊渊博

    2004-01-01

    The meshless local boundary integral equation method is a currently developed numerical method, which combines the advantageous features of Galerkin finite element method(GFEM), boundary element method(BEM) and element free Galerkin method(EFGM), and is a truly meshless method possessing wide prospects in engineering applications.The companion solution and all the other formulas required in the meshless local boundary integral equation for a thin plate were presented, in order to make this method apply to solve the thin plate problem.

  7. Three-Dimensional Elasticity Solutions for Sound Radiation of Functionally Graded Materials Plates considering State Space Method

    Directory of Open Access Journals (Sweden)

    Tieliang Yang

    2016-01-01

    Full Text Available This paper presents an analytical study for sound radiation of functionally graded materials (FGM plate based on the three-dimensional theory of elasticity. The FGM plate is a mixture of metal and ceramic, and its material properties are assumed to have smooth and continuous variation in the thickness direction according to a power-law distribution in terms of volume fractions of the constituents. Based on the three-dimensional theory of elasticity and state space method, the governing equations with variable coefficients of the FGM plate are derived. The sound radiation of the vibration plate is calculated with Rayleigh integral. Comparisons of the present results with those of solutions in the available literature are made and good agreements are achieved. Finally, some parametric studies are carried out to investigate the sound radiation properties of FGM plates.

  8. 2D simulation and analysis of fluid flow between two sinusoidal parallel plates using lattice Bolzmann method

    Directory of Open Access Journals (Sweden)

    Marković Jelena Đ.

    2013-01-01

    Full Text Available In order to obtain a better heat transfer, it is important to enhance fluid mixing in heat exchangers. Since there are negative effects when heat exchangers are operating in turbulent regime (like significant pressure drop, increased size of the pump it is necessary to apply the techniques which would provide better fluid mixing when heat exchangers are operating in laminar regime. Investigations have shown that use of sinusoidal instead of flat plates results in this effect. This study is a result of two dimensional simulation of fluid flow between two parallel sinusoidal plates. Simulation was done with the use of modified Openlb code, based on lattice Boltzmann method. Reynolds number was varied from 200 to 1000, and space between the plates was varied from 3cm to 5 cm. Results showed that sinusoidal plates enhance fluid mixing, especially with greater values of Re and smaller space between the plates, which is in agreement with previous investigations.

  9. Method of producing exfoliated graphite composite compositions for fuel cell flow field plates

    Energy Technology Data Exchange (ETDEWEB)

    Zhamu, Aruna; Shi, Jinjun; Guo, Jiusheng; Jang, Bor Z

    2014-04-08

    A method of producing an electrically conductive composite composition, which is particularly useful for fuel cell bipolar plate applications. The method comprises: (a) providing a supply of expandable graphite powder; (b) providing a supply of a non-expandable powder component comprising a binder or matrix material; (c) blending the expandable graphite with the non-expandable powder component to form a powder mixture wherein the non-expandable powder component is in the amount of between 3% and 60% by weight based on the total weight of the powder mixture; (d) exposing the powder mixture to a temperature sufficient for exfoliating the expandable graphite to obtain a compressible mixture comprising expanded graphite worms and the non-expandable component; (e) compressing the compressible mixture at a pressure within the range of from about 5 psi to about 50,000 psi in predetermined directions into predetermined forms of cohered graphite composite compact; and (f) treating the so-formed cohered graphite composite to activate the binder or matrix material thereby promoting adhesion within the compact to produce the desired composite composition. Preferably, the non-expandable powder component further comprises an isotropy-promoting agent such as non-expandable graphite particles. Further preferably, step (e) comprises compressing the mixture in at least two directions. The method leads to composite plates with exceptionally high thickness-direction electrical conductivity.

  10. Method of producing exfoliated graphite composite compositions for fuel cell flow field plates

    Science.gov (United States)

    Zhamu, Aruna; Shi, Jinjun; Guo, Jiusheng; Jang, Bor Z

    2014-04-08

    A method of producing an electrically conductive composite composition, which is particularly useful for fuel cell bipolar plate applications. The method comprises: (a) providing a supply of expandable graphite powder; (b) providing a supply of a non-expandable powder component comprising a binder or matrix material; (c) blending the expandable graphite with the non-expandable powder component to form a powder mixture wherein the non-expandable powder component is in the amount of between 3% and 60% by weight based on the total weight of the powder mixture; (d) exposing the powder mixture to a temperature sufficient for exfoliating the expandable graphite to obtain a compressible mixture comprising expanded graphite worms and the non-expandable component; (e) compressing the compressible mixture at a pressure within the range of from about 5 psi to about 50,000 psi in predetermined directions into predetermined forms of cohered graphite composite compact; and (f) treating the so-formed cohered graphite composite to activate the binder or matrix material thereby promoting adhesion within the compact to produce the desired composite composition. Preferably, the non-expandable powder component further comprises an isotropy-promoting agent such as non-expandable graphite particles. Further preferably, step (e) comprises compressing the mixture in at least two directions. The method leads to composite plates with exceptionally high thickness-direction electrical conductivity.

  11. Efficiency of Removing Chromium from Plating Industry Wastewater using the Electrocoagulation Method

    Directory of Open Access Journals (Sweden)

    Borghe-ei S.M.1 PhD,

    2015-06-01

    Full Text Available Aims Chromium is one of the most important metallic pollutants in plating industry wastewater. This toxic metal is a serious threat to human health and to the environment due to its cumulative effects and non-degradability. This research intended to study the effects of pH, contact time, and voltage on the degree of chromium removal from wastewater of plating industry by using the electrocoagulation method. Materials & Methods This laboratory research conducted from late May to late November 2012. A 1000cc reactor at laboratory scale was used that included 4 aluminum electrodes of 90% purity, dimensions of 5 by 10cm, and thickness of 1mm, with parallel arrangement. Synthetic chromium-bearing wastewater was prepared at the initial concentration of 50mg/l. The process is done at pH values of 3, 7, and 9, electric potentials of 20, 30, and 40 volts contact durations of 20, 40, 60, and 80 minutes. Findings The degree of chromium reduction did not change linearly with time in the solution and strongly depended on the pH. The efficiency of chromium removal in the samples had an ascending trend with increases in voltage from 20 to 30 and 40 volts. The degree of chromium removal increased at longer contact times. Conclusion Lower pH, more contact time and higher voltages are effective factors in the chromium removal from wastewater by coagulation method.

  12. High-Temperature Thermal Conductivity Measurement Apparatus Based on Guarded Hot Plate Method

    Science.gov (United States)

    Turzo-Andras, E.; Magyarlaki, T.

    2017-10-01

    An alternative calibration procedure has been applied using apparatus built in-house, created to optimize thermal conductivity measurements. The new approach compared to those of usual measurement procedures of thermal conductivity by guarded hot plate (GHP) consists of modified design of the apparatus, modified position of the temperature sensors and new conception in the calculation method, applying the temperature at the inlet section of the specimen instead of the temperature difference across the specimen. This alternative technique is suitable for eliminating the effect of thermal contact resistance arising between a rigid specimen and the heated plate, as well as accurate determination of the specimen temperature and of the heat loss at the lateral edge of the specimen. This paper presents an overview of the specific characteristics of the newly developed "high-temperature thermal conductivity measurement apparatus" based on the GHP method, as well as how the major difficulties are handled in the case of this apparatus, as compared to the common GHP method that conforms to current international standards.

  13. Application of Homotopy Analysis Method to the Unsteady Squeezing Flow of a Second-Grade Fluid between Circular Plates

    Directory of Open Access Journals (Sweden)

    Mohammad Mehdi Rashidi

    2010-01-01

    Full Text Available We investigated an axisymmetric unsteady two-dimensional flow of nonconducting, incompressible second grade fluid between two circular plates. The similarity transformation is applied to reduce governing partial differential equation (PDE to a nonlinear ordinary differential equation (ODE in dimensionless form. The resulting nonlinear boundary value problem is solved using homotopy analysis method and numerical method. The effects of appropriate dimensionless parameters on the velocity profiles are studied. The total resistance to the upper plate has been calculated.

  14. The boundary point method for Reissner′s plates%Reissner型板边界点法

    Institute of Scientific and Technical Information of China (English)

    吴约; 王左辉

    2001-01-01

    In this paper, a series of particular solutions are formed by utilizing correspondent Reissher′s plate fundamental solutions. Thus all elements in the coefficient matrix of boundary element equations for plates to be solved will be determined by boundary point method. In the process of solving, interpolation and numerical integration are not needed and numerical treatment for singular integration is avoided, meanwhile, the calculation of physical characteristics of any point does not depend on boundary unknowns to be solved, therefore, the accuracy is excellent. The method presented may be applied to solving the problems of all kinds of plates and shells no matter if the problem is isotropic or anisotropic. But it should be noticed that the matrix of all particular solution field should conform with the fundamental solution of the specific problem.%文章采用Reissner型板基本解来构建一系列特解,再通过边界点法确定边界元方程系效矩阵的全部元素。解算中不涉及具体插值,不用数值积分,避免了奇性处理,而任意点物理量的计算不依赖于待解的边界未知量,算效高,精度好。该法还可用来分析其它各类板壳问题,无论是各向同性还是各向异性的,不同的只是应按各自的基本解来构造全特解场矩阵。

  15. A novel prediction method of vibration and acoustic radiation for rectangular plate with particle dampers

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Dongqiang; Wu, Chengjun [Xi' an Jiaotong University, Xi' an (China)

    2016-03-15

    Particle damping technology is widely used in mechanical and structural systems or civil engineering to reduce vibration and suppress noise as a result of its high efficiency, simplicity and easy implementation, low cost, and energy-saving characteristic without the need for any auxiliary power equipment. Research on particle damping theory has focused on the vibration response of the particle damping structure, but the acoustic radiation of the particle damping structure is rarely investigated. Therefore, a feasible modeling method to predict the vibration response and acoustic radiation of the particle damping structure is desirable to satisfy the actual requirements in industrial practice. In this paper, a novel simulation method based on multiphase flow theory of gas particle by COMSOL multiphysics is developed to study the vibration and acoustic radiation characteristics of a cantilever rectangular plate with Particle dampers (PDs). The frequency response functions and scattered far-field sound pressure level of the plate without and with PDs under forced vibration are predicted, and the predictions agree well with the experimental results. Results demonstrate that the added PDs have a significant effect on vibration damping and noise reduction for the primary structure. The presented work in this paper shows that the theoretical work is valid, which can provide important theoretical guidance for low-noise optimization design of particle damping structure. This model also has an important reference value for the noise control of this kind of structure.

  16. Orifice plate for controlling solids flow, methods of use thereof and articles comprising the same

    Energy Technology Data Exchange (ETDEWEB)

    Jukkola, Glen D.; Teigen, Bard C.

    2017-01-31

    Disclosed herein is an orifice plate comprising one or more plates having orifices disposed therein; the orifices being operative to permit the flow of solids from a moving bed heat exchanger to a solids flow control system; where the orifice plate is downstream of a tube bundle of the moving bed heat exchanger and upstream of the solids flow control system and wherein the orifice plate is operative to evenly distribute the flow of solids in the solids flow control system.

  17. Liquid crystal thermography. A method for monitoring temperature gradients in microtitration plates.

    Science.gov (United States)

    Oliver, D G; Sanders, A H; Jang, L; Poy, D; Van Heuvelen, A

    1983-03-11

    Precise quantitative heat transfer information in microtitration plates can be obtained by filling the wells of a microtitration plate with cholesteric liquid crystals and incubating the plates at the desired temperature in different incubators. The liquid crystals indicate temperature by changes in discrete reproducible colors over various temperature ranges. With these instrumented plates, interwell thermal gradients may be documented visually and are in close agreement with results obtained by using wire thermocouple measuring techniques.

  18. Thermal buckling analysis of annular FGM plate having variable thickness under thermal load of arbitrary distribution by finite element method

    Energy Technology Data Exchange (ETDEWEB)

    Ghomshei, Mansour Mohieddin; Abbasi, Vahid [Islamic Azad University, Alborz (Iran, Islamic Republic of)

    2013-04-15

    In this paper, a finite element formulation is developed for analyzing the axisymmetric thermal buckling of FGM annular plates of variable thickness subjected to thermal loads generally distributed nonuniformly along the plate radial coordinate. The FGM assumed to be isotropic with material properties graded in the thickness direction according to a simple power-law in terms of the plate thickness coordinate, and has symmetry with respect to the plate midplane. At first, the pre-buckling plane elasticity problem is developed and solved using the finite element method, to determine the distribution of the pre-buckling in-plane forces in terms of the temperature rise distribution. Subsequently, based on Kierchhoff plate theory and using the principle of minimum total potential energy, the weak form of the differential equation governing the plate thermal stability is derived, then by employing the finite element method, the stability equations are solved numerically to evaluate the thermal buckling load factor. Convergence and validation of the presented finite element model are investigated by comparing the numerical results with those available in the literature. Parametric studies are carried out to cover the effects of parameters including thickness-to-radius ratio, taper parameter and boundary conditions on the thermal buckling load factor of the plates.

  19. Comparison of discrimination methods for alpha radiation signals using imaging plates.

    Science.gov (United States)

    Chen, B; Zhuo, W

    2012-11-01

    The discrimination of different radiation signals is important for quantitative measurements of naturally occurring radionulides by using the technique of imaging plates (IPs). In this study, four discrimination algorithms previously proposed for discriminating and counting the incident alpha signals were experimentally compared from the view points of linearity response, the discrimination capability of alpha signals from beta signals and the detection uncertainty. The results showed that all the methods had a good linearity response and could discriminate alpha signals from beta signals. In general, a larger region of interest (ROI) has a higher detection efficiency, but the discrimination capability of alpha signals from beta signals is worse. By taking into account both the detection efficiency and the uncertainty of detection, the algorithm using an ROI of 5 × 100 μm × 100 μm was considered to be the most appropriate method for quantitative measurements of alpha radiation.

  20. Vibration Analysis of Rectangular Plates with One or More Guided Edges via Bicubic B-Spline Method

    Directory of Open Access Journals (Sweden)

    W.J. Si

    2005-01-01

    Full Text Available A simple and accurate method is proposed for the vibration analysis of rectangular plates with one or more guided edges, in which bicubic B-spline interpolation in combination with a new type of basis cubic B-spline functions is used to approximate the plate deflection. This type of basis cubic B-spline functions can satisfy simply supported, clamped, free, and guided edge conditions with easy numerical manipulation. The frequency characteristic equation is formulated based on classical thin plate theory by performing Hamilton's principle. The present solutions are verified with the analytical ones. Fast convergence, high accuracy and computational efficiency have been demonstrated from the comparisons. Frequency parameters for 13 cases of rectangular plates with at least one guided edge, which are possible by approximate or numerical methods only, are presented. These results are new in literature.

  1. Generalized equations of finite difference method in the problems of dynamic load calculation for thin bending plates

    Directory of Open Access Journals (Sweden)

    Gabbasov Radek Fatykhovich

    Full Text Available Bending plate is widely used in the construction of large-span structures. Its advantage is light weight, industrial production, low cost and easy installation. Implementing the algorithm for calculating bending plates in engineering practice is an important issue of the construction science. The generalized equations of finite difference method is a new trend in the calculation of building construction. FDM with generalized equation provides additional options for an engineer along with other methods (FEM. In the article the algorithm for dynamic calculation of thin bending plates basing on FDM was developed. The computer programs for dynamic calculation were created on the basis of the algorithm. The authors come to the conclusion that the more simple equations of FDM can be used in case of solving the impulse load problems in dynamic load calculation of thin bending plate.

  2. Petrifilm rapid S. aureus Count Plate method for rapid enumeration of Staphylococcus aureus in selected foods: collaborative study.

    Science.gov (United States)

    Silbernagel, K M; Lindberg, K G

    2001-01-01

    A rehydratable dry-film plating method for Staphylococcus aureus in foods, the 3M Petrifilm Rapid S. aureus Count Plate method, was compared with AOAC Official Method 975.55 (Staphylococcus aureus in Foods). Nine foods-instant nonfat dried milk, dry seasoned vegetable coating, frozen hash browns, frozen cooked chicken patty, frozen ground raw pork, shredded cheddar cheese, fresh green beans, pasta filled with beef and cheese, and egg custard-were analyzed for S. aureus by 13 collaborating laboratories. For each food tested, the collaborators received 8 blind test samples consisting of a control sample and 3 levels of inoculated test sample, each in duplicate. The mean log counts for the methods were comparable for pasta filled with beef and cheese; frozen hash browns; cooked chicken patty; egg custard; frozen ground raw pork; and instant nonfat dried milk. The repeatability and reproducibility variances of the Petrifilm Rapid S. aureus Count Plate method were similar to those of the standard method.

  3. Determination of low methylmercury concentrations in peat soil samples by isotope dilution GC-ICP-MS using distillation and solvent extraction methods.

    Science.gov (United States)

    Pietilä, Heidi; Perämäki, Paavo; Piispanen, Juha; Starr, Mike; Nieminen, Tiina; Kantola, Marjatta; Ukonmaanaho, Liisa

    2015-04-01

    Most often, only total mercury concentrations in soil samples are determined in environmental studies. However, the determination of extremely toxic methylmercury (MeHg) in addition to the total mercury is critical to understand the biogeochemistry of mercury in the environment. In this study, N2-assisted distillation and acidic KBr/CuSO4 solvent extraction methods were applied to isolate MeHg from wet peat soil samples collected from boreal forest catchments. Determination of MeHg was performed using a purge and trap GC-ICP-MS technique with a species-specific isotope dilution quantification. Distillation is known to be more prone to artificial MeHg formation compared to solvent extraction which may result in the erroneous MeHg results, especially with samples containing high amounts of inorganic mercury. However, methylation of inorganic mercury during the distillation step had no effect on the reliability of the final MeHg results when natural peat soil samples were distilled. MeHg concentrations determined in peat soil samples after distillation were compared to those determined after the solvent extraction method. MeHg concentrations in peat soil samples varied from 0.8 to 18 μg kg(-1) (dry weight) and the results obtained with the two different methods did not differ significantly (p=0.05). The distillation method with an isotope dilution GC-ICP-MS was shown to be a reliable method for the determination of low MeHg concentrations in unpolluted soil samples. Furthermore, the distillation method is solvent-free and less time-consuming and labor-intensive when compared to the solvent extraction method. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Management of infectious fractures with "Non-Contact Plate" (NCP) method.

    Science.gov (United States)

    Alemdar, Celil; Azboy, Ibrahim; Atiç, Ramazan; Özkul, Emin; Gem, Mehmet; Kapukaya, Ahmet

    2015-09-01

    The aim of this study was to evaluate the outcomes of internal fixation with Non-Contact Plating (NCP) after deep infection caused by previous surgeries of the tibia or femur fractures. The study included 15 patients (4 female and 11 male). The mean age patients was 36.6 years (range, 21-64 years). There were 6 femur and 9 tibia fractures. The mean follow-up period was 25.7 months (range, 15-45 months). The study comprised 11 open and 4 closed fractures. External fixator was used in 3, plate in 4, and intramedullary nail in 8 patients for index surgery. Deep infection was diagnosed via clinical findings, laboratory parameters, and microbiological evaulation. Deep infection was diagnosed within a mean period of 5.5 weeks (range, 2-10 weeks). The infecting organism was methicillin-resistant staphylococcus aureus (MRSA) in 5, methicillin-sensitive staphylococcus aureus (MSSA) in 6, pseudomonas auroginosa in 2, and enterobacteriacea in 2 patients. Union achieved in all patients. Mean time to union was 17 (range, 11-38) weeks. Delayed union was observed in 3 patients who required additional surgeries. Of these one patient developed osteomyelitis. The NCP is an effective alternative method in the treatment of deep infection encountered after internal or external fixation for the tibia, or femur fractures.

  5. Comparison of Primary Models to Predict Microbial Growth by the Plate Count and Absorbance Methods.

    Science.gov (United States)

    Pla, María-Leonor; Oltra, Sandra; Esteban, María-Dolores; Andreu, Santiago; Palop, Alfredo

    2015-01-01

    The selection of a primary model to describe microbial growth in predictive food microbiology often appears to be subjective. The objective of this research was to check the performance of different mathematical models in predicting growth parameters, both by absorbance and plate count methods. For this purpose, growth curves of three different microorganisms (Bacillus cereus, Listeria monocytogenes, and Escherichia coli) grown under the same conditions, but with different initial concentrations each, were analysed. When measuring the microbial growth of each microorganism by optical density, almost all models provided quite high goodness of fit (r(2) > 0.93) for all growth curves. The growth rate remained approximately constant for all growth curves of each microorganism, when considering one growth model, but differences were found among models. Three-phase linear model provided the lowest variation for growth rate values for all three microorganisms. Baranyi model gave a variation marginally higher, despite a much better overall fitting. When measuring the microbial growth by plate count, similar results were obtained. These results provide insight into predictive microbiology and will help food microbiologists and researchers to choose the proper primary growth predictive model.

  6. A Novel Two-Step Method for Fabricating Silver Plating Cotton Fabrics

    Directory of Open Access Journals (Sweden)

    Hao Liu

    2016-01-01

    Full Text Available A novel two-step method was presented for fabricating silver plating cotton fabrics (SPCFs with high electrical conductivity and excellent washing fastness. First, polydopamine (PDA film was coated on the surface of cotton fabrics by in situ polymerization of dopamine, the silver ions in silver nitrate solution were reduced by the catechol groups of polydopamine, and silver nanoparticles were combined with polydopamine by covalent bond on the surface of cotton fabrics. Second, silver ions were reduced by glucose, and silver plating was coated on the surface. Subsequently, the properties of SPCFs were characterized by field emission scanning electron microscopy (FESEM, X-ray photoelectron spectroscopy (XPS and thermogravimetric analysis (TGA, and so forth. With the increasing of silver-ammonia solution concentration or dopamine concentration, the surface resistivity of SPCFs decreases and gradually stabilized. The surface resistivity of the SPCFs can reach 0.12±0.02 Ω, and electromagnetic shielding effectiveness (ESE of the SPCFs can reach 58.5±4.5 dB. Conductive fabrics have wide application prospect in many of fields, such as antibacterial, intelligent textiles, smart garments, electromagnetic shielding, and flexible sensors.

  7. Comparison of agar dilution, broth microdilution, disk diffusion, E-test, and BACTEC radiometric methods for antimicrobial susceptibility testing of clinical isolates of the Nocardia asteroides complex.

    Science.gov (United States)

    Ambaye, A; Kohner, P C; Wollan, P C; Roberts, K L; Roberts, G D; Cockerill, F R

    1997-01-01

    An evaluation was undertaken to determine the optimal method for the in vitro susceptibility testing of 26 Nocardia asteroides complex isolates to the following antimicrobial agents: amikacin, ampicillin, amoxicillin-clavulanate, ceftriaxone, ciprofloxacin, erythromycin, imipenem, minocycline, and trimethoprim-sulfamethoxazole. Five testing methods were studied including the agar dilution, broth microdilution, and disk diffusion methods, the epsilometer test (E-test), and the BACTEC radiometric method. Results for each antimicrobial agent and each testing method were interpreted as indicating susceptibility, intermediate susceptibility, or resistance according to current guidelines of the National Committee for Clinical Laboratory Standards (NCCLS) for bacteria that grow aerobically and were then compared to a "gold standard" susceptibility test result. The gold standard result for each Nocardia isolate was established by a consensus of the results of the majority of testing methods used in the study. When the results were combined for all antimicrobial agents tested against all Nocardia isolates by all methods, the BACTEC radiometric method produced the highest level of agreement (97.9%) with the consensus results and had the fewest very major (n = 1), major (n = 2), and minor (n = 2) errors. In contrast, the results of the agar dilution method were in least agreement (93.2%) with the consensus results, and this method also produced the most very major (n = 8), major (n = 4), and, along with the disk diffusion method, minor (n = 6) errors. For all test methods, interpretive errors were most frequent when testing ampicillin or amoxicillin-clavulanate. Moreover, for all Nocardia nova isolates tested, ampicillin susceptibility results by any of the testing methods were not in agreement with the results of testing for beta-lactamase by the nitrocefin (Cefinase) disk method. We conclude that among the methods evaluated, the BACTEC radiometric method appeared to be the

  8. Improved non-dimensional dynamic influence function method for vibration analysis of arbitrarily shaped plates with clamped edges

    Directory of Open Access Journals (Sweden)

    Sang-Wook Kang

    2016-03-01

    Full Text Available A new formulation for the non-dimensional dynamic influence function method, which was developed by the authors, is proposed to efficiently extract eigenvalues and mode shapes of clamped plates with arbitrary shapes. Compared with the finite element and boundary element methods, the non-dimensional dynamic influence function method yields highly accurate solutions in eigenvalue analysis problems of plates and membranes including acoustic cavities. However, the non-dimensional dynamic influence function method requires the uneconomic procedure of calculating the singularity of a system matrix in the frequency range of interest for extracting eigenvalues because it produces a non-algebraic eigenvalue problem. This article describes a new approach that reduces the problem of free vibrations of clamped plates to an algebraic eigenvalue problem, the solution of which is straightforward. The validity and efficiency of the proposed method are illustrated through several numerical examples.

  9. Experimental comparison and validation of hot-ball method with guarded hot plate method on polyurethane foams

    Science.gov (United States)

    Hudec, Ján; Glorieux, Christ; Dieška, Peter; Kubičár, Ľudovít

    2016-07-01

    The Hot-ball method is an innovative transient method for measuring thermophysical properties. The principle is based on heating of a small ball, incorporated in measured medium, by constant heating power and simultaneous measuring of the ball's temperature response since the heating was initiated. The shape of the temperature response depends on thermophysical properties of the medium, where the sensor is placed. This method is patented by Institute of Physics, SAS, where the method and sensors based on this method are being developed. At the beginning of the development of sensors for this method we were oriented on monitoring applications, where relative precision is much more important than accuracy. Meanwhile, the quality of sensors was improved good enough to be used for a new application - absolute measuring of thermophysical parameters of low thermally conductive materials. This paper describes experimental verification and validation of measurement by hot-ball method. Thanks to cooperation with Laboratory of Soft Matter and Biophysics of Catholic University of Leuven in Belgium, established Guarded Hot Plate method was used as a reference. Details about measuring setups, description of the experiments and results of the comparison are presented.

  10. High-throughput culturing of fungi from plant litter by a dilution-to-extinction technique.

    Science.gov (United States)

    Collado, Javier; Platas, Gonzalo; Paulus, Barbara; Bills, Gerald F

    2007-06-01

    High-throughput bacterial cultivation has improved the recovery of slow-growing and previously uncultured bacteria. The most robust high-throughput methods are based on techniques of 'dilution to extinction' or 'extinction culturing'. The low-density partitioning of CFUs in tubes or microwells exploits the fact that the number of culturable species typically increases as inoculum density decreases. Bacterial high-throughput culturing methods were adapted to fungi to generate large numbers of fungal extinction cultures. The efficiency of extinction culturing was assessed by comparing it with particle filtration and automated plate-streaking. Equal volumes of particle suspension from five litter collections of the New Zealand forest tree Elaeocarpus dentatus were compared. Dilute particle suspensions of litter were pipetted into 48-well tissue culture plates containing 1 mL of agar medium per well. Particle volumes from the same samples were applied to continuous agar surfaces in Omnitray plates by automated streaking, and fungal diversity and richness were measured. The spectrum of isolates was assessed by microscopy and sequencing of the ITS or 28S region of the rRNA gene. Estimates of species diversity between the two methods were comparable, but extinction culturing increased species richness. Compared with plating methods using continuous surfaces, extinction culturing distributes fungal propagules over partitioned surfaces. Intercolony interactions are reduced, permitting longer incubation times, and colony initiation and recovery improved. Effort to evaluate and recover colonies from fungal isolation plates was substantially reduced.

  11. Temperature-independent pectin gel method for aerobic plate count in dairy and nondairy food products: collaborative study.

    Science.gov (United States)

    Roth, J N

    1988-01-01

    Ten laboratories participated in a collaborative study to compare the pectin-based plate count (PC) Redigel method with the aerobic plate count and standard plate count agar-based standard methods for the estimation of total bacterial counts in 9 different nondairy food and dairy food products. The foods were cream, homogenized milk, raw milk, cheese, raw chicken, raw oysters, frozen broccoli, flour, and spices. Each laboratory analyzed 6 samples (3 sample pairs) of each food group. Counts obtained by the pectin-based plate count and agar-based plate count methods differed significantly (P less than 0.05) only for homogenized milk, where the pectin gel method resulted in higher counts. The actual counts were higher in the pectin gel method in 8 of the 9 food groups. The log means for pectin gel and agar-based media, respectively, for the 9 food groups were: cream 8.106 and 7.844; homogenized milk 8.642 and 8.231; raw milk 8.711 and 8.423; chicken 7.654 and 7.645; oysters 7.201 and 7.180; broccoli 7.102 and 6.798; cheese 8.045 and 8.055; flour 4.112 and 3.988; spice 5.379 and 5.314. The repeatability standard deviations favored the pectin gel method in 6 of the 9 foods tested. The reproducibility standard deviations favored the pectin gel method in 7 of the 9 foods tested. These results strongly support the suitability of the pectin gel method as an alternative to agar-based plate count and other methods for total bacterial counts in nondairy and dairy food products. The pectin gel method has been adopted official first action.

  12. Reconstruction of Dispersive Lamb Waves in Time Plates Using a Time Reversal Method

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Hyun Jo [Wonkwang University, Iksan (Korea, Republic of)

    2008-02-15

    Time reversal (TR) of nondispersive body waves has been used in many applications including ultrasonic NDE. However, the study of the TR method for Lamb waves on thin structures is not well established. In this paper, the full reconstruction of the input signal is investigated for dispersive Lamb waves by introducing a time reversal operator based on the Mindlin plate theory. A broadband and a narrowband input waveform are employed to reconstruct the A{sub 0} mode of Lamb wave propagations. Due to the frequency dependence of the TR process of Lamb waves, different frequency components of the broadband excitation are scaled differently during the time reversal process and the original input signal cannot be fully restored. This is the primary reason for using a narrowband excitation to enhance the flaw detectability

  13. Local Projection-Based Stabilized Mixed Finite Element Methods for Kirchhoff Plate Bending Problems

    Directory of Open Access Journals (Sweden)

    Xuehai Huang

    2013-01-01

    Full Text Available Based on stress-deflection variational formulation, we propose a family of local projection-based stabilized mixed finite element methods for Kirchhoff plate bending problems. According to the error equations, we obtain the error estimates of the approximation to stress tensor in energy norm. And by duality argument, error estimates of the approximation to deflection in H1-norm are achieved. Then we design an a posteriori error estimator which is closely related to the equilibrium equation, constitutive equation, and nonconformity of the finite element spaces. With the help of Zienkiewicz-Guzmán-Neilan element spaces, we prove the reliability of the a posteriori error estimator. And the efficiency of the a posteriori error estimator is proved by standard bubble function argument.

  14. Effect of crack on the impact response of plates by the extended finite element method (X-FEM)

    Energy Technology Data Exchange (ETDEWEB)

    Tiberkak, Rachid [University of Blida, Soumaa (Algeria); Bachene, Mourad [University of Medea, Medea (Algeria); Rechak, Said [Ecole Nationale Polytechnique, Algiers (Algeria)

    2014-06-15

    The dynamic response of cracked isotropic plates subjected to impact loading is studied in this paper. The impact properties of cracked plate are compared with the virgin ones to predict the eventual presence of discontinuities in plates. The extended finite element method (X-FEM) is employed in the mathematical modeling of the impact problem, wherein the effects of shear deformation is considered. Conventional finite element without any discontinuity is initially conducted in the numerical implementation. Enriched functions are then added to the nodal displacement field for element nodes that contain cracks. The effects of crack length and crack position on contact force and on plate deflection are analyzed. Results show that the maximal contact force decreases as the deflection increases with increasing crack length a . The effect of crack position on the dynamic response is less pronounced when the crack is near the fixed end.

  15. Single Transducer Ultrasonic Imaging Method that Eliminates the Effect of Plate Thickness Variation in the Image

    Science.gov (United States)

    Roth, Don J.

    1996-01-01

    This article describes a single transducer ultrasonic imaging method that eliminates the effect of plate thickness variation in the image. The method thus isolates ultrasonic variations due to material microstructure. The use of this method can result in significant cost savings because the ultrasonic image can be interpreted correctly without the need for machining to achieve precise thickness uniformity during nondestructive evaluations of material development. The method is based on measurement of ultrasonic velocity. Images obtained using the thickness-independent methodology are compared with conventional velocity and c-scan echo peak amplitude images for monolithic ceramic (silicon nitride), metal matrix composite and polymer matrix composite materials. It was found that the thickness-independent ultrasonic images reveal and quantify correctly areas of global microstructural (pore and fiber volume fraction) variation due to the elimination of thickness effects. The thickness-independent ultrasonic imaging method described in this article is currently being commercialized under a cooperative agreement between NASA Lewis Research Center and Sonix, Inc.

  16. Binding of nontarget microorganisms from food washes to anti-Salmonella and anti-E. coli O157 immunomagnetic beads: minimizing the errors of random sampling in extreme dilute systems.

    Science.gov (United States)

    Irwin, Peter; Nguyen, Thi Ly-Huong; Chen, Chin-Yi

    2008-05-01

    For most applications, 3-5 observations, or samplings (n), are utilized to estimate total aerobic plate count in an average population (μ) that is greater than about 50 cells, or colony forming units (CFU), per sampled volume. We have chosen to utilize a 6 × 6 drop plate method for bacterial colony selection because it offers the means to rapidly perform all requisite dilutions in a 96-well format and plate these dilutions on solid media using minimal materials. Besides traditional quantitative purposes, we also need to select colonies which are well-separated from each other for the purpose of bacterial identification. To achieve this goal using the drop plate format requires the utilization of very dilute solutions (μ food samples along with most probable number (MPN) analyses and it was found that the two enumeration methods did not differ significantly.

  17. Estimation of plate material properties by means of a complex wavenumber fit using Hankel's functions and the image source method

    Science.gov (United States)

    Roozen, N. B.; Leclère, Q.; Ege, K.; Gerges, Y.

    2017-03-01

    This paper presents a new wave fitting approach to estimate the frequency dependent material properties of thin isotropic plate structures from an experimentally obtained vibrational field, exciting the plate at a single point. The method projects the measurement data on to an analytical image source model, in which Hankel's functions are used for a description of the wave fields emanating from the point of excitation, including the reflected wave fields from the edges of the finite plate. By minimizing the error between the projected field and the measured field, varying the complex wave number and the source strengths of the image sources, an optimum fit is searched for. Thus the source strengths of the image sources do not need to be determined theoretically, but are estimated from the fit on to the experimental data instead (thus avoiding difficulties in theoretically assessing the reflection coefficient of the edges of the plate). The approach uses a complex wavenumber fit, enabling the determination of the dynamic stiffness of the plate structure and its damping properties as function of frequency. The method is especially suited for plates with a sufficient amount of damping, excited at high frequencies.

  18. Enumeration of total coliforms and E. coli in foods by the SimPlate coliform and E. coli color indicator method and conventional culture methods: collaborative study.

    Science.gov (United States)

    Feldsine, Philip T; Lienau, Andrew H; Roa, Nerie H; Green, Shannon T

    2005-01-01

    The relative effectiveness of the SimPlate Coliform and E. coli Color Indicator (CEc-CI) method was compared to the AOAC 3-tube Most Probable Number (MPN) methods for enumerating and confirming coliforms and Escherichia coli in foods (966.23 and 966.24). In this study, test portions were prepared and analyzed according to the conditions stated in both the AOAC methods and SimPlate directions for use. Six food types were artificially contaminated with coliform bacteria and E. coli: frozen burritos, frozen broccoli, fluid pasteurized milk, whole almond nut meats, cheese, and powdered cake mix. Method comparisons were conducted. Overall, the SimPlate method demonstrated coliform and E. coli counts compared to the AOAC reference methods for the majority of food types and levels analyzed. In all cases, the repeatability and reproducibility of the SimPlate CEc-CI method were not different from those of the reference methods and in certain cases, were statistically better than those of the AOAC 3-tube MPN methods. These results indicate that the SimPlate CEc-CI method and the reference culture methods are comparable for enumeration of both total coliforms and E. coli in foods.

  19. Comparison of a quantitative microtiter method, a quantitative automated method, and the plate-count method for determining microbial complement resistance.

    Science.gov (United States)

    Lee, M D; Wooley, R E; Brown, J; Spears, K R; Nolan, L K; Shotts, E B

    1991-01-01

    A quantitative microtiter method for determining the degree of complement resistance or sensitivity of microorganisms is described. The microtiter method is compared with a quantitative automated system and the standard plate-count technique. Data were accumulated from 30 avian Escherichia coli isolates incubated at 35 C with either chicken plasma or heat-inactivated chicken plasma. Analysis of data generated by the automated system and plate-count techniques resulted in a classification of the microorganisms into three groups: those sensitive to the action of complement; those of intermediate sensitivity to the action of complement; and those resistant to the action of complement. Although the three methods studied did not agree absolutely, there were statistically significant correlations among them.

  20. A force plate based method for the calibration of force/torque sensors.

    Science.gov (United States)

    Faber, Gert S; Chang, Chien-Chi; Kingma, Idsart; Schepers, H Martin; Herber, Sebastiaan; Veltink, Peter H; Dennerlein, Jack T

    2012-04-30

    This study describes a novel calibration method for six-degrees-of-freedom force/torque sensors (FTsensors) using a pre-calibrated force plate (FP) as a reference measuring device. In this calibration method, the FTsensor is rigidly connected to a FP and force/torque data are synchronously recorded while a dynamic functional loading procedure is applied by the researcher. Based on these data an accurate calibration matrix for the FTsensor can easily be obtained via least-squares optimization. Using this calibration method, this study further investigated what loading methods are appropriate for the calibration of FTsensors intended for ambulatory measurement of ground reaction forces (GRFs). Seven different loading methods were compared (e.g., walking, pushing while standing on the FTsensor). Calibration matrices were calculated based on the raw data from the seven loading methods individually and all loading methods combined. Performance of these calibration matrices was subsequently compared in an in situ trial. During the in situ trial, five common work tasks (e.g., walking, manual lifting, pushing) were performed by an experimenter, while standing on the FP wearing a "ForceShoe" with two calibrated FTsensors attached to its sole. Root-mean-square differences (RMSDs) between the FTsensor and FP outcomes were calculated over all tasks. Using the calibration matrices based on all loading methods combined resulted in small RMSDs (GRF: <8 N, center of pressure: <2 mm). Using the calibration matrices based on "pushing against manual resistance" resulted in similar RMSDs, proving it to be the best single loading method.

  1. A simple method for the detection of protease activity on agar plates using Bromocresolgreen Dye

    Directory of Open Access Journals (Sweden)

    Ponnuswamy Vijayaraghavan

    2013-07-01

    proteolytic activity using bromocresol green dye on substrate agar plates. Two methods were highlighted in this article. The first method was adopted to determine the proteolytic activity by flooding bromocresol green reagent on casein/skimmed milk agar plates. Later, a minimum of 0.0015% of bromocresol green was incorporated with the substrate agar plates before autoclaving to detect the proteolytic activity of bacteria. The proteolytic activity appeared as a colourless zone, while the rest of the plates were greenish-blue in colour which was pH dependent. This method was easy to perform and cheap.  

  2. New Approaches on Quantification of Campylobacter jejuni in Poultry Samples: The Use of Digital PCR and Real-time PCR against the ISO Standard Plate Count Method

    Science.gov (United States)

    Papić, Bojan; Pate, Mateja; Henigman, Urška; Zajc, Urška; Gruntar, Igor; Biasizzo, Majda; Ocepek, Matjaž; Kušar, Darja

    2017-01-01

    Campylobacteriosis is the most frequently reported bacterial food-borne illness in the European Union and contaminated broiler meat is considered the most important source of infection in humans. The aim of the present study was to evaluate real-time PCR (qPCR) and digital PCR (dPCR) for quantification of Campylobacter jejuni in 75 broiler neck-skin samples collected from a poultry slaughterhouse, and to compare them with the ISO 10272-2 standard plate count method. For qPCR standard curve, C. jejuni-negative neck-skin samples were spiked with C. jejuni suspension with a known number of bacterial cells. The observed CFU/g values by qPCR correlated greatly with the expected values and qPCR showed good performance with the reliable limit of detection (rLOD) and limit of quantification (LOQ) of three and 31 target copies per reaction, respectively. However, both rLOD (1219 CFU/g) and LOQ (12,523 CFU/g) were beyond the EFSA-proposed critical limit of 500–1,000 CFU/g of neck skin. Although C. jejuni cell counts were ≤1,000 CFU/g in only 7/75 samples by plate counting, they were ≤LOQ in 60/75 and ≤rLOD in 26/75 (≤1,000 CFU/g in 24/75) samples by qPCR. A strong and statistically significant correlation was observed between qPCR and dPCR. Both PCR-based methods correlated significantly with the plate count method; however, the correlation was moderate. Using the Bland–Altman analysis, an average agreement was noted between all three methods, although with a large standard deviation. A significant bias toward overestimation in dPCR was observed, probably due to the relatively high number of false positive calls. The linear dynamic range was comparable in both PCR-based methods; however, qPCR proved to be more suitable for routine use. In the future, the establishment of a reliable molecular quantification of C. jejuni in poultry samples showing a wide range of contamination levels down to the proposed critical limit is needed to enable time- and cost

  3. Robust scatter correction method for cone-beam CT using an interlacing-slit plate

    Science.gov (United States)

    Huang, Kui-Dong; Xu, Zhe; Zhang, Ding-Hua; Zhang, Hua; Shi, Wen-Long

    2016-06-01

    Cone-beam computed tomography (CBCT) has been widely used in medical imaging and industrial nondestructive testing, but the presence of scattered radiation will cause significant reduction of image quality. In this article, a robust scatter correction method for CBCT using an interlacing-slit plate (ISP) is carried out for convenient practice. Firstly, a Gaussian filtering method is proposed to compensate the missing data of the inner scatter image, and simultaneously avoid too-large values of calculated inner scatter and smooth the inner scatter field. Secondly, an interlacing-slit scan without detector gain correction is carried out to enhance the practicality and convenience of the scatter correction method. Finally, a denoising step for scatter-corrected projection images is added in the process flow to control the noise amplification The experimental results show that the improved method can not only make the scatter correction more robust and convenient, but also achieve a good quality of scatter-corrected slice images. Supported by National Science and Technology Major Project of the Ministry of Industry and Information Technology of China (2012ZX04007021), Aeronautical Science Fund of China (2014ZE53059), and Fundamental Research Funds for Central Universities of China (3102014KYJD022)

  4. Tuning of Feedback Decoupling Controller for Two-Dimensional Heat Plate by Using VRFT Method

    Science.gov (United States)

    Matsunaga, Nobutomo; Nakano, Masahiko; Okajima, Hiroshi; Kawaji, Shigeyasu

    In manufacturing processes, inappropriate thermal distribution, which is observed in both steady and transient states of the thermal plant, leads to inferior quality. For a plant with strong thermal interaction, decoupling control is effective in precisely tuning the control system. We proposed the decoupling controller based on the temperature-difference feedback model. However, no parameter-identification method of thermal interaction has been presented so far. Traditionally, iterative tuning by trial and error has been used to tune the controller parameters. In the case of an industrial plant, the tuning time would be long because of the large time constants of the plant. Recently, the virtual reference feedback tuning (VRFT) method, which can be used for off-line tuning of the controller parameters using a set of I/O data, has been studied to examine the possibility of shortening the tuning time. In this paper, a VRFT method for the feedback decoupling controller is proposed for a two-dimensional heat plate by taking consideration the thermal interaction property. The effectiveness of this VRFT method is evaluated by performing an experimental simulation.

  5. Numerical simulation of two-dimensional spouted bed with draft plates by discrete element method

    Institute of Scientific and Technical Information of China (English)

    Yongzhi ZHAO; Yi CHENG; Maoqiang JIANG; Yong JIN

    2008-01-01

    A discrete element method (DEM)-computa-tional fluid dynamics (CFD) two-way coupling method was employed to simulate the hydrodynamics in a two-dimensional spouted bed with draft plates. The motion of particles was modeled by the DEM and the gas flow was modeled by the Navier-Stokes equation. The interactions between gas and particles were considered using a two-way coupling method. The motion of particles in the spouted bed with complex geometry was solved by com-bining DEM and boundary element method (BEM). The minimal spouted velocity was obtained by the BEM-DEM-CFD simulation and the variation of the flow pat-tern in the bed with different superficial gas velocity was studied. The relationship between the pressure drop of the spouted bed and the superficial gas velocity was achieved from the simulations. The radial profile of the averaged vertical velocities of particles and the profile of the aver-aged void fraction in the spout and the annulus were stat-istically analyzed. The flow characteristics of the gas-solid system in the two-dimensional spouted bed were clearly described by the simulation results.

  6. Application of Approximation Full-Load Distribution Method to Pass Scheduling on Plate Mill With Hydro-Bending System

    Institute of Scientific and Technical Information of China (English)

    HU Xian-lei; ZHANG Qi-sheng; ZHAO Zhong; TIAN Yong; LIU Xiang-hua; WANG Guo-dong

    2006-01-01

    The influence of positive bending system on plate crown control was researched. The approximation full-load distribution method for pass scheduling was put forward. This method can not only make full use of the mill capacity with decreased pass number, but also give quality product of excellent flatness.

  7. A Simple Method of Detecting Chlamydia Trachomatis Using Enzymatically Amplified DNA and Immobilized Probes on Microtiter Plate

    Institute of Scientific and Technical Information of China (English)

    王仁礼; 熊艳; 张龙兴; 蒋秀蓉; 张忠恕

    1998-01-01

    We have developed a simple and economical method for Chlamydia trachomatis detecting, called microtiter plate hybridization (PCR-MPtt) , which may replace standard PCR. This method is similar to that of an ELISA. Briefly, the PCR products labeled at the 5' termini with biotin were hybridized with probes immobilized on a microtiter well

  8. Influence of the ARC patterning method and annealing on the contact adhesion of Ni/Cu-plated solar cells

    Science.gov (United States)

    Baik, Jong Wook; Lee, Sang Hee; Lee, Doo Won; Lee, Soo Hong

    2016-05-01

    Ni/Cu two-step plating is a promising metallization technique because low contact resistance and improved contact adhesion can be achieved after the Ni annealing process. Also, narrow fingers, which are required for high-efficiency solar cells, can be formed by plating. However, the reliability of contact adhesion is still considered one obstacle to industrializing solar cells with plated metal contacts. In this experiment, the influence of ARC opening methods on plated contact adhesion was investigated because the roughnesses of the Si surfaces produced by using pico-second laser ablation and photolithography may be different. Also, the annealing process was conducted before and after plating Cu/Ag metal stacks. The sequence of the annealing can be significant for efficient production because plating is a wet process while annealing is a dry process. The contact adhesion was measured by using a peel-off test. The test was conducted on a 1.5-mm-wide by a 60 ~ 70- mm-long bus bar area. A 3.2-N/mm adhesion force was recorded as a highest average value along the bus bar.

  9. The hp-MITC finite element method for the Reissner-Mindlin plate problem

    Science.gov (United States)

    Ainsworth, Mark; Pinchedez, Katia

    2002-11-01

    The popular MITC finite elements used for the approximation of the Reissner-Mindlin plate are extended to the case where elements of non-uniform degree p distribution are used on locally refined meshes. Such an extension is of particular interest to the hp-version and hp-adaptive finite element methods. A priori error bounds are provided showing that the method is locking-free. The analysis is based on new approximation theoretic results for non-uniform Brezzi-Douglas-Fortin-Marini spaces, and extends the results obtained in the case of uniform order approximation on globally quasi-uniform meshes presented by Stenberg and Suri (SIAM J. Numer. Anal. 34 (1997) 544). Numerical examples illustrating the theoretical results and comparing the performance with alternative standard Galerkin approaches are presented for two new benchmark problems with known analytic solution, including the case where the shear stress exhibits a boundary layer. The new method is observed to be locking-free and able to provide exponential rates of convergence even in the presence of boundary layers.

  10. Methods for testing Zernike phase plates and a report on silicon-based phase plates with reduced charging and improved ageing characteristics.

    Science.gov (United States)

    Marko, Michael; Meng, Xing; Hsieh, Chyongere; Roussie, James; Striemer, Christopher

    2013-11-01

    Imaging with Zernike phase plates is increasingly being used in cryo-TEM tomography and cryo-EM single-particle applications. However, rapid ageing of the phase plates, together with the cost and effort in producing them, present serious obstacles to widespread adoption. We are experimenting with phase plates based on silicon chips that have thin windows; such phase plates could be mass-produced and made available at moderate cost. The windows are coated with conductive layers to reduce charging, and this considerably extends the useful life of the phase plates compared to traditional pure-carbon phase plates. However, a compromise must be reached between robustness and transmission through the phase-plate film. Details are given on testing phase-plate performance by means of imaging an amorphous thin film and evaluating the power spectra of the images.

  11. Solution of a Problem of Natural Oscillations of a Finite Plate with Fastened Base and Method of Levinson

    Directory of Open Access Journals (Sweden)

    Vardanov A.H.

    2010-12-01

    Full Text Available The exact solution of three-dimensional problem of free vibrations of a finite elastic plate with fastened base is considered. The problem is solved with the Lame potentials and by method of Levinson, which has formulated to solve the three-dimensional plate problem with free faces. The dispersion equation for the vibration frequencies and the self functions characterizing the amplitude of oscillation are derived. Problems are solved in the case of the Navier conditions defined on the facial surfaces. It is shown that the method of Levinson leads to the exact solution.

  12. Dry rehydratable film method for rapid enumeration of coliforms in foods (3M Petrifilm Rapid Coliform Count plate): collaborative study.

    Science.gov (United States)

    Kinneberg, Karen M; Lindberg, Kathryn G

    2002-01-01

    A rehydratable dry-film plating method for coliforms in foods, the 3M Petrifilm Rapid Coliform Count plate method, was compared with the U.S. Food and Drug Administration's Bacteriological Analytical Manual method for nondairy foods and the American Public Health Association's Standard Methods for the Examination of Dairy Products (SMEDP) method for dairy foods. Six food types, vanilla ice cream, cheddar cheese, fresh refrigerated uncooked pasta, wheat flour, prepared frozen macaroni and cheese, and frozen hash browns, were analyzed for coliforms by 11 collaborating laboratories. For each food product tested, the collaborators received 8 blind samples consisting of a control sample and 3 levels of inoculated sample, each in duplicate. The mean log counts for the methods were comparable. The repeatability and reproducibility variances of the Petrifilm Rapid Coliform Count method at 14 and 24 h were not significantly different from those of the standard methods.

  13. A semi-Lagrangian transport method for kinetic problems with application to dense-to-dilute polydisperse reacting spray flows

    Science.gov (United States)

    Doisneau, François; Arienti, Marco; Oefelein, Joseph C.

    2017-01-01

    For sprays, as described by a kinetic disperse phase model strongly coupled to the Navier-Stokes equations, the resolution strategy is constrained by accuracy objectives, robustness needs, and the computing architecture. In order to leverage the good properties of the Eulerian formalism, we introduce a deterministic particle-based numerical method to solve transport in physical space, which is simple to adapt to the many types of closures and moment systems. The method is inspired by the semi-Lagrangian schemes, developed for Gas Dynamics. We show how semi-Lagrangian formulations are relevant for a disperse phase far from equilibrium and where the particle-particle coupling barely influences the transport; i.e., when particle pressure is negligible. The particle behavior is indeed close to free streaming. The new method uses the assumption of parcel transport and avoids to compute fluxes and their limiters, which makes it robust. It is a deterministic resolution method so that it does not require efforts on statistical convergence, noise control, or post-processing. All couplings are done among data under the form of Eulerian fields, which allows one to use efficient algorithms and to anticipate the computational load. This makes the method both accurate and efficient in the context of parallel computing. After a complete verification of the new transport method on various academic test cases, we demonstrate the overall strategy's ability to solve a strongly-coupled liquid jet with fine spatial resolution and we apply it to the case of high-fidelity Large Eddy Simulation of a dense spray flow. A fuel spray is simulated after atomization at Diesel engine combustion chamber conditions. The large, parallel, strongly coupled computation proves the efficiency of the method for dense, polydisperse, reacting spray flows.

  14. A semi-Lagrangian transport method for kinetic problems with application to dense-to-dilute polydisperse reacting spray flows

    Energy Technology Data Exchange (ETDEWEB)

    Doisneau, François, E-mail: fdoisne@sandia.gov; Arienti, Marco, E-mail: marient@sandia.gov; Oefelein, Joseph C., E-mail: oefelei@sandia.gov

    2017-01-15

    For sprays, as described by a kinetic disperse phase model strongly coupled to the Navier–Stokes equations, the resolution strategy is constrained by accuracy objectives, robustness needs, and the computing architecture. In order to leverage the good properties of the Eulerian formalism, we introduce a deterministic particle-based numerical method to solve transport in physical space, which is simple to adapt to the many types of closures and moment systems. The method is inspired by the semi-Lagrangian schemes, developed for Gas Dynamics. We show how semi-Lagrangian formulations are relevant for a disperse phase far from equilibrium and where the particle–particle coupling barely influences the transport; i.e., when particle pressure is negligible. The particle behavior is indeed close to free streaming. The new method uses the assumption of parcel transport and avoids to compute fluxes and their limiters, which makes it robust. It is a deterministic resolution method so that it does not require efforts on statistical convergence, noise control, or post-processing. All couplings are done among data under the form of Eulerian fields, which allows one to use efficient algorithms and to anticipate the computational load. This makes the method both accurate and efficient in the context of parallel computing. After a complete verification of the new transport method on various academic test cases, we demonstrate the overall strategy's ability to solve a strongly-coupled liquid jet with fine spatial resolution and we apply it to the case of high-fidelity Large Eddy Simulation of a dense spray flow. A fuel spray is simulated after atomization at Diesel engine combustion chamber conditions. The large, parallel, strongly coupled computation proves the efficiency of the method for dense, polydisperse, reacting spray flows.

  15. A robust two-node, 13 moment quadrature method of moments for dilute particle flows including wall bouncing

    Science.gov (United States)

    Sun, Dan; Garmory, Andrew; Page, Gary J.

    2017-02-01

    For flows where the particle number density is low and the Stokes number is relatively high, as found when sand or ice is ingested into aircraft gas turbine engines, streams of particles can cross each other's path or bounce from a solid surface without being influenced by inter-particle collisions. The aim of this work is to develop an Eulerian method to simulate these types of flow. To this end, a two-node quadrature-based moment method using 13 moments is proposed. In the proposed algorithm thirteen moments of particle velocity, including cross-moments of second order, are used to determine the weights and abscissas of the two nodes and to set up the association between the velocity components in each node. Previous Quadrature Method of Moments (QMOM) algorithms either use more than two nodes, leading to increased computational expense, or are shown here to give incorrect results under some circumstances. This method gives the computational efficiency advantages of only needing two particle phase velocity fields whilst ensuring that a correct combination of weights and abscissas is returned for any arbitrary combination of particle trajectories without the need for any further assumptions. Particle crossing and wall bouncing with arbitrary combinations of angles are demonstrated using the method in a two-dimensional scheme. The ability of the scheme to include the presence of drag from a carrier phase is also demonstrated, as is bouncing off surfaces with inelastic collisions. The method is also applied to the Taylor-Green vortex flow test case and is found to give results superior to the existing two-node QMOM method and is in good agreement with results from Lagrangian modelling of this case.

  16. Differential specificity of selective culture media for enumeration of pathogenic vibrios: advantages and limitations of multi-plating methods.

    Science.gov (United States)

    Nigro, Olivia D; Steward, Grieg F

    2015-04-01

    Plating environmental samples on vibrio-selective chromogenic media is a commonly used technique that allows one to quickly estimate concentrations of putative vibrio pathogens or to isolate them for further study. Although this approach is convenient, its usefulness depends directly on how well the procedure selects against false positives. We tested whether a chromogenic medium, CHROMagar Vibrio (CaV), used alone (single-plating) or in combination (double-plating) with a traditional medium thiosulfate-citrate-bile-salts (TCBS), could improve the discrimination among three pathogenic vibrio species (Vibrio cholerae, Vibrio parahaemolyticus, and Vibrio vulnificus) and thereby decrease the number of false-positive colonies that must be screened by molecular methods. Assays were conducted on water samples from two estuarine environments (one subtropical, one tropical) in a variety of seasonal conditions. The results of the double-plating method were confirmed by PCR and 16S rRNA sequencing. Our data indicate that there is no significant difference in the false-positive rate between CaV and TCBS when using a single-plating technique, but determining color changes on the two media sequentially (double-plating) reduced the rate of false positive identification in most cases. The improvement achieved was about two-fold on average, but varied greatly (from 0- to 5-fold) and depended on the sampling time and location. The double-plating method was most effective for V. vulnificus in warm months, when overall V. vulnificus abundance is high (false positive rates as low as 2%, n=178). Similar results were obtained for V. cholerae (minimum false positive rate of 16%, n=146). In contrast, the false positive rate for V. parahaemolyticus was always high (minimum of 59%, n=109). Sequence analysis of false-positive isolates indicated that the majority of confounding isolates are from the Vibrionaceae family, however, members of distantly related bacterial groups were also able to

  17. Use of Fourier transformed infrared spectrophotometer (FTIR) for determination of breastmilk output by the deuterium dilution method among Senegalese women.

    Science.gov (United States)

    Cissé, Aïta Sarr; Bluck, Leslie; Diaham, Babou; Dossou, Nicole; Guiro, Amadou Tidiane; Wade, Salimata

    2002-09-01

    Breastmilk output can be estimated from the mother's total body water and water turnover rates after oral administration of deuterium oxide. Usually the deuterium enrichments are determined using a isotope ratio mass spectrometer, which is expensive and requires a specialist for operation and maintenance. Such equipment is difficult to set up in developing countries. A less expensive method was developed which uses a Fourier transform infrared spectrophotometer (FTIR) for deuterium enrichment analysis. This study evaluated the constraints of using FTIR to study lactating women in Senegal. The deuterium isotope method was found to be adequate for free living subjects and presented few constraints except for the duration of the saliva sampling (14 days). The method offers the opportunity to determine simultaneously breastmilk output, mother's body composition, and breastfeeding practices. Deuterium sample enrichments measured with FTIR were fast and easy, but for spectrum quality some environmental control is required to optimize the results.

  18. Boundary integral equation methods and numerical solutions thin plates on an elastic foundation

    CERN Document Server

    Constanda, Christian; Hamill, William

    2016-01-01

    This book presents and explains a general, efficient, and elegant method for solving the Dirichlet, Neumann, and Robin boundary value problems for the extensional deformation of a thin plate on an elastic foundation. The solutions of these problems are obtained both analytically—by means of direct and indirect boundary integral equation methods (BIEMs)—and numerically, through the application of a boundary element technique. The text discusses the methodology for constructing a BIEM, deriving all the attending mathematical properties with full rigor. The model investigated in the book can serve as a template for the study of any linear elliptic two-dimensional problem with constant coefficients. The representation of the solution in terms of single-layer and double-layer potentials is pivotal in the development of a BIEM, which, in turn, forms the basis for the second part of the book, where approximate solutions are computed with a high degree of accuracy. The book is intended for graduate students and r...

  19. Impact Localization Method for Composite Plate Based on Low Sampling Rate Embedded Fiber Bragg Grating Sensors

    Directory of Open Access Journals (Sweden)

    Zhuo Pang

    2017-01-01

    Full Text Available Fiber Bragg Grating (FBG sensors have been increasingly used in the field of Structural Health Monitoring (SHM in recent years. In this paper, we proposed an impact localization algorithm based on the Empirical Mode Decomposition (EMD and Particle Swarm Optimization-Support Vector Machine (PSO-SVM to achieve better localization accuracy for the FBG-embedded plate. In our method, EMD is used to extract the features of FBG signals, and PSO-SVM is then applied to automatically train a classification model for the impact localization. Meanwhile, an impact monitoring system for the FBG-embedded composites has been established to actually validate our algorithm. Moreover, the relationship between the localization accuracy and the distance from impact to the nearest sensor has also been studied. Results suggest that the localization accuracy keeps increasing and is satisfactory, ranging from 93.89% to 97.14%, on our experimental conditions with the decrease of the distance. This article reports an effective and easy-implementing method for FBG signal processing on SHM systems of the composites.

  20. A screening method for the optimal selection of plate heat exchanger configurations

    Directory of Open Access Journals (Sweden)

    Pinto J.M.

    2002-01-01

    Full Text Available An optimization method for determining the best configuration(s of gasketed plate heat exchangers is presented. The objective is to select the configuration(s with the minimum heat transfer area that still satisfies constraints on the number of channels, the pressure drop of both fluids, the channel flow velocities and the exchanger thermal effectiveness. The configuration of the exchanger is defined by six parameters, which are as follows: the number of channels, the numbers of passes on each side, the fluid locations, the feed positions and the type of flow in the channels. The resulting configuration optimization problem is formulated as the minimization of the exchanger heat transfer area and a screening procedure is proposed for its solution. In this procedure, subsets of constraints are successively applied to eliminate infeasible and nonoptimal solutions. Examples show that the optimization method is able to successfully determine a set of optimal configurations with a minimum number of exchanger evaluations. Approximately 5 % of the pressure drop and channel velocity calculations and 1 % of the thermal simulations are required for the solution.

  1. MULTIPLE RECIPROCITY METHOD WITH TWO SERIES OF SEQUENCES OF HIGH-ORDER FUNDAMENTAL SOLUTION FOR THIN PLATE BENDING

    Institute of Scientific and Technical Information of China (English)

    丁方允; 丁睿; 李炳杰

    2003-01-01

    The boundary value problem of plate bending problem on two-parameter foundation was discussed. Using two series of the high-order fundamental solution sequences, namely, the fundamental solution sequences for the multi-harmonic operator and Laplace operator, applying the multiple reciprocity method (MRM), the MRM boundary integral equation for plate bending problem was constructed. It proves that the boundary integral equation derived from MRM is essentially identical to the conventional boundary integral equation. Hence the convergence analysis of MRM for plate bending problem can be obtained by the error estimation for the conventional boundary integral equation. In addition, this method can extend to the case of more series of the high-order fundamental solution sequences.

  2. Comparison of two tracer gas dilution methods for the determination of clothing ventilation and of vapour resistance

    NARCIS (Netherlands)

    Havenith, G.; Zhang, P.; Hatcher, K.; Daanen, H.A.M.

    2010-01-01

    Clothing microclimate ventilation is an important parameter in climatic stress and in contaminated environments. The two main methods for its determination (Crockford et al. (CR) 1972 and Lotens and Havenith (LH) 1988) were, after further development, compared in terms of reproducibility, validity

  3. A comparative study on the customized design of mandibular reconstruction plates using finite element method

    Directory of Open Access Journals (Sweden)

    Abdulrahman Al-Ahmari

    2015-07-01

    Full Text Available Mandible defects and its deformities are serious complications and its precise reconstruction is one of the most challenging tasks in oral maxillofacial surgery. The commercially available standard mandible implants are manually bended before surgery to custom fit the patient’s jaw. A slight mismatch in the plate and bone alignment may result in the implant failure. However, with the integration of computer-aided design, rapid prototyping, and advanced imaging systems (computed tomography or magnetic resonance imaging, it is possible to produce a customized mandible implant that can precisely fit the patient’s jaw. The aim of this article is to compare a new design of customized mandible implant (sinewave plate and compare it with the commonly used straight implant design. The finite element–simulated results reveal that the commonly used straight reconstruction plates are more prone to loosening of the screws due to its higher strain concentration on the screw hole when compared to newly designed sinewave reconstruction plate. Moreover, the straight plate is more sensitive to the chewing load variations and develops almost 20% increase in the stresses when compared to sinewave plate. The study reveals that the sinewave reconstruction plate can significantly enhance the stability and safety of the mandible implant.

  4. In Silico Calculation of Infinite Dilution Activity Coefficients of Molecular Solutes in Ionic Liquids: Critical Review of Current Methods and New Models Based on Three Machine Learning Algorithms.

    Science.gov (United States)

    Paduszyński, Kamil

    2016-08-22

    The aim of the paper is to address all the disadvantages of currently available models for calculating infinite dilution activity coefficients (γ(∞)) of molecular solutes in ionic liquids (ILs)-a relevant property from the point of view of many applications of ILs, particularly in separations. Three new models are proposed, each of them based on distinct machine learning algorithm: stepwise multiple linear regression (SWMLR), feed-forward artificial neural network (FFANN), and least-squares support vector machine (LSSVM). The models were established based on the most comprehensive γ(∞) data bank reported so far (>34 000 data points for 188 ILs and 128 solutes). Following the paper published previously [J. Chem. Inf. Model 2014, 54, 1311-1324], the ILs were treated in terms of group contributions, whereas the Abraham solvation parameters were used to quantify an impact of solute structure. Temperature is also included in the input data of the models so that they can be utilized to obtain temperature-dependent data and thus related thermodynamic functions. Both internal and external validation techniques were applied to assess the statistical significance and explanatory power of the final correlations. A comparative study of the overall performance of the investigated SWMLR/FFANN/LSSVM approaches is presented in terms of root-mean-square error and average absolute relative deviation between calculated and experimental γ(∞), evaluated for different families of ILs and solutes, as well as between calculated and experimental infinite dilution selectivity for separation problems benzene from n-hexane and thiophene from n-heptane. LSSVM is shown to be a method with the lowest values of both training and generalization errors. It is finally demonstrated that the established models exhibit an improved accuracy compared to the state-of-the-art model, namely, temperature-dependent group contribution linear solvation energy relationship, published in 2011 [J. Chem

  5. 40 CFR 1065.240 - Dilution air and diluted exhaust flow meters.

    Science.gov (United States)

    2010-07-01

    ... heat exchanger, either a CFV or a PDP will also function as a passive flow controller in a CVS system.... For any type of diluted exhaust flow meter, condition the flow as needed to prevent wakes, eddies... to at least 10 pipe diameters) or by using specially designed tubing bends, orifice plates or...

  6. Evaluation of dry sheet medium culture plate (Compactdry TC) method for determining numbers of bacteria in food samples.

    Science.gov (United States)

    Mizuochi, S; Kodaka, H

    2000-05-01

    The Compactdry, a ready-to-use and self-diffusible dry medium sheet culture system, has been developed by the Nissui Pharmaceutical Co. Ltd. for enumerating bacteria in food. The Compactdry consists of special spread sheet with culture medium that is the same as standard method nutrients, a cold water-soluble gelling agent, and a unique plastic dish. The procedure for bacterial examination in a sample solution (1 ml) is to just inoculate a test solution into the center of the self-diffusible medium and incubate at 35 degrees C for 48 h. The Compactdry TC (CTC) for the enumeration of total aerobic bacteria from 97 food samples was compared with the standard plate count (SPC) method and 3M Petrifilm aerobic count plates (PAC). The correlation coefficients between the CTC and SPC method, the CTC and PAC, and the PAC and SPC method were 0.97, 0.99, and 0.97, respectively. The Compactdry system is useful for the enumeration of total aerobic bacteria in food and may be a possible suitable alternative to the conventional pour-plate or the Petrifilm plate methods.

  7. The Plate Model: a visual method of teaching meal planning. DAIS Project Group. Diabetes Atherosclerosis Intervention Study.

    Science.gov (United States)

    Camelon, K M; Hådell, K; Jämsén, P T; Ketonen, K J; Kohtamäki, H M; Mäkimatilla, S; Törmälä, M L; Valve, R H

    1998-10-01

    Dietitians from Canada, Finland, France, and Sweden have explored methods of teaching meal planning to persons with diabetes and dyslipidemia in the Diabetes Atherosclerosis Intervention Study. The Plate Model, a method commonly used in Europe, is a simple alternative to the traditional exchange-based method for teaching meal planning. In this visual method, a dinner plate serves as a pie chart to show proportions of the plate that should be covered by various food groups. Portions of foods and appropriate food choices can be depicted for meals and snacks in assorted forms of the model. Methods of presenting the model range from professional photography to hand-drawn sketches and displays of food replicas. Benefits of the model for adult learners include enhancement of the connection between dietary theory and practice, promotion of memory retention and understanding through visual messages, and experience of a positive approach to nutrition counseling. Various cuisines and festive foods can be incorporated into the model. The Plate Model offers a meal planning approach that is simple and versatile. The effectiveness of the model and its applications to other populations need to be evaluated.

  8. Volumetric topological analysis: a novel method for trabecular bone characterization on the continuum between plates and rods

    Science.gov (United States)

    Saha, Punam K.; Xu, Yan; Liang, Guoyuan; Duan, Hong

    2009-02-01

    Trabecular bone (TB) is a complex quasi-random network of interconnected struts and plates. TB constantly remodels to adapt dynamically to the stresses to which it is subjected (Wolff's Law). In osteoporosis, this dynamic equilibrium between bone formation and resorption is perturbed, leading to bone loss and structural deterioration, both increasing fracture risk. Bone's mechanical competence can only be partly explained by variations in bone mineral density, which led to the notion of bone structural quality. Previously, we developed digital topological analysis or DTA which classifies plates, rods, profiles, edges and junctions in a TB skeletal representation. Although the method has become quite popular, a major limitation is that DTA produces hard classifications only, failing to distinguish between narrow and wide plates. Here, we present a new method called volumetric topological analysis or VTA for quantification of regional topology in complex quasi-random TB networks. At each TB voxel, the method uniquely classifies the topology on the continuum between perfect plates and rods. Therefore, the method is capable of detecting early alterations of trabeculae from plates to rods according to the known etiology of osteoporotic bone loss. Here, novel ideas of geodesic distance transform, geodesic scale and feature propagation have been introduced and combined with DTA and fuzzy distance transform methods conceiving the new VTA technology. The method has been applied to MDCT and μCT images of a cadaveric distal tibia specimen and the results have been quantitatively evaluated. Specifically, intra- and inter-modality reproducibility of the method has been examined and the results are found very promising.

  9. Modified Layer-Removal Method for Measurement of Residual Stress in Pre-stretched Aluminium Alloy Plate

    Institute of Scientific and Technical Information of China (English)

    Liangbao Liu; Jianfei Sun; Wuyi Chen; Pengfei Sun

    2015-01-01

    Residual stress is one of the factors affecting the machining deformation of monolithic structure parts in the aviation industry. Thus, the studies on machining deformation rules induced by residual stresses largely depend on correctly and efficiently measuring the residual stresses of workpieces. A modified layer⁃removal method is proposed to measure residual stress by analysing the characteristics of a traditional layer⁃removal method. The coefficients of strain release are then deduced according to the simulation results using the finite element method ( FEM) . Moreover, the residual stress in a 7075T651 aluminium alloy plate is measured using the proposed method, and the results are then analyzed and compared with the data obtained by the traditional methods. The analysis indicates that the modified layer⁃removal method is effective and practical for measuring the residual stress distribution in pre⁃stretched aluminium alloy plates.

  10. Iterative methods for obtaining solvation structures on a solid plate: The methods for Surface Force Apparatus and Atomic Force Microscopy in Liquids

    CERN Document Server

    Amano, Ken-ich

    2013-01-01

    We propose iterative methods for obtaining solvation structures on a solid plate which use force distributions measured by surface force apparatus (SFA) and atomic force microscopy (AFM) as input data. Two model systems are considered here. In the model system for SFA, the same two solid plates are immersed in a solvent, and a probe tip and a solid plate are immersed in a solvent in the model system for AFM. Advantages of the iterative methods are as follows: The iterative method for SFA can obtain the solvation structure, for example, in a Lennard-Jones liquid; The iterative method for AFM can obtain the solvation structure without an input datum of solvation structure around the probe tip.

  11. Interfacial structure of steel-Al-28Pb bonding plate with semisolid rolling-casting method

    Institute of Scientific and Technical Information of China (English)

    张鹏; 杜云慧; 刘汉武; 曾大本; 崔建忠; 巴立民

    2004-01-01

    Fe-Al compound at the interface of steel-mushy Al-28Pb bonding plate was studied quantitatively. The relationship between ratio of Fe-Al compound at interface and bonding parameters such as preheating temperature of steel plate, solid volume fraction of Al-28Pb slurry and rolling speed, was established by artificial neural networks perfectly. The results show that when the bonding parameters are 546 ℃ for preheating temperature of steel plate,43.5% for solid volume fraction of Al-28Pb slurry and 8.6 mm/s for rolling speed, the reasonable ratio of Fe-Al compound corresponding to the largest interfacial shear strength of bonding plate is obtained as 71.5%. This reasonable ratio of Fe-Al compound is a quantitative criterion of interfacial embrittlement, that is, when the ratio of FeAl compound at interface is larger than 71.5%, interfacial embrittlement will occur.

  12. A new method to assess temporal features of gait initiation with a single force plate.

    Science.gov (United States)

    Moineau, Bastien; Boisgontier, Matthieu P; Barbieri, Guillaume; Nougier, Vincent

    2014-01-01

    The aim of this study was to investigate whether time of toe-off and heel-contact during gait initiation could be assessed with a single force plate. Twenty subjects performed ten self-paced gait initiations and seven other subjects performed ten gait initiations in four new conditions (slow, fast, obstacle and splint). Several force-plate parameters were measured with a single force plate, and actual toe-off and heel-contact were assessed with a motion analysis system. Results showed strong temporal correlations and closeness (r=.86-.99, mean error=3-86 ms) between two force-plate parameters and the kinematics events (toe-off and heel-contact). These new parameters may be of interest to easily measure duration of anticipatory postural adjustments and swing phase during clinical assessments.

  13. Postbuckling analysis of variable stiffness composite plates using a finite element-based perturbation method

    NARCIS (Netherlands)

    Rahman, T.; IJsselmuiden, S.T.; Abdalla, M.M.; Jansen, E.L.

    2011-01-01

    Modern fiber placement machines allow laminates with spatially varying stiffness properties to be manufactured. In earlier research, the authors optimized variable stiffness plates for maximum buckling load, demonstrating significant improvements in load-carrying capacity. In aerospace applications,

  14. Theoretical prediction of hysteretic rubber friction in ball on plate configuration by finite element method

    Directory of Open Access Journals (Sweden)

    2009-11-01

    Full Text Available This paper has investigated theoretically the influence of sliding speed and temperature on the hysteretic friction in case of a smooth, reciprocating steel ball sliding on smooth rubber plate by finite element method (FEM. Generalized Maxwell-models combined with Mooney-Rivlin model have been used to describe the material behaviour of the ethylenepropylene-diene-monomer (EPDM rubber studied. Additionally, the effect of the technique applied at the parameter identification of the material model and the number of Maxwell elements on the coefficient of friction (COF was also investigated. Finally, the open parameter of the Greenwood-Tabor analytical model has been determined from a fit to the FE results. By fitting, as usual, the Maxwell-model to the storage modulus master curve the predicted COF, in a broad frequency range, will be underestimated even in case of 40-term Maxwell-model. To obtain more accurate numerical prediction or to provide an upper limit for the hysteretic friction, in the interesting frequency range, the Maxwell parameters should be determined, as proposed, from a fit to the measured loss factor master curve. This conclusion can be generalized for all the FE simulations where the hysteresis plays an important role.

  15. Fabrication and microwave properties of hollow nickel spheres prepared by electroless plating and template corrosion method

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Guiqin, E-mail: wanggq@dlut.edu.cn; Wang, Lifang; Gan, Yulin; Lu, Wei

    2013-07-01

    Using carbonyl iron as template, hollow nickel spheres were prepared by electroless plating on carbonyl iron and template corrosion method. The samples were characterized by X-ray diffraction (XRD), X-ray fluorescence spectrometer (XRF), transmission electron microscope (TEM), scanning electron microscope (SEM), vibrating sample magnetometer (VSM) and vector network analyzer. Results showed that the shell thickness can be controlled by adjusting the loadage of carbonyl iron templates. The hollow nickel spheres exhibited good magnetic properties with a saturation magnetization of 48.56 emu/g and enhanced coercivity (as high as 260 Oe). The real (ε′) and imaginary (ε″) parts of complex permittivity of hollow nickel spheres first increased and then decreased as the shell thickness increased, and the sample with the thinnest shell showed the lowest complex permittivity. For the complex permeability, the resonance peak shifted to the lower frequency and then moved to higher frequency, as the shell thickness increased. The microwave absorption performances could be tuned by changing the shell thickness. In this study, the minimum reflection loss (RL) value of −27.2 dB was obtained at 13.4 GHz with a matching thickness of 1.4 mm and the effective absorption band (RL <−5 dB) from 11.8 to 18 GHz, covering the whole Ku-band (12.4−18 GHz).

  16. Concept of automatic programming of NC machine for metal plate cutting by genetic algorithm method

    Directory of Open Access Journals (Sweden)

    B. Vaupotic

    2005-12-01

    Full Text Available Purpose: In this paper the concept of automatic programs of the NC machine for metal plate cutting by genetic algorithm method has been presented.Design/methodology/approach: The paper was limited to automatic creation of NC programs for two-dimensional cutting of material by means of adaptive heuristic search algorithms.Findings: Automatic creation of NC programs in laser cutting of materials combines the CAD concepts, the recognition of features and creation and optimization of NC programs. The proposed intelligent system is capable to recognize automatically the nesting of products in the layout, to determine the incisions and sequences of cuts forming the laid out products. Position of incisions is determined at the relevant places on the cut. The system is capable to find the shortest path between individual cuts and to record the NC program.Research limitations/implications: It would be appropriate to orient future researches towards conceiving an improved system for three-dimensional cutting with optional determination of positions of incisions, with the capability to sense collisions and with optimization of the speed and acceleration during cutting.Practical implications: The proposed system assures automatic preparation of NC program without NC programer.Originality/value: The proposed concept shows a high degree of universality, efficiency and reliability and it can be simply adapted to other NC-machines.

  17. Forming mechanism of radial V-shaped microgrooves on plate using step punching method

    Directory of Open Access Journals (Sweden)

    Xiang Jian-hua

    2015-02-01

    Full Text Available The finned surface can increase the specific surface area, which could enhance the boiling efficiency of the working medium to realize the enhancement of heat transfer performance. This research adopted a step punching method to form a radial microgroove structure on the surface of a copper plate. The scanning electron microscopy analysis indicates that when the pressed metal is in the deformation range, it will flow under extrusion and is subject to the reaction force from the metal outside the deformation range, so a micro-finned structure nearby the punching tool is formed. And the deformation area of the formed microgroove is higher than the workpiece’s primitive surface. The relationships of the punching interference length Li with θc, ac, and αpt are analyzed; and the influence of forming parameters on the groove surface morphology as well as the relationships among these parameters are discussed. When the punching depth ac is 0.3 mm and the punching feeding angle θc is 2°–4°, the finned surface of the radial V-shaped microgrooves can be obtained.

  18. A simple and effective plating method to screen polycyclic aromatic hydrocarbon-degrading bacteria under various redox conditions.

    Science.gov (United States)

    Um, Youngsoon; Chang, Matthew Wook; Holoman, Tracey Pulliam

    2010-09-01

    Agar plates with a polycyclic aromatic hydrocarbon (PAH) layer have been used to screen for microorganisms that degrade PAHs, leaving clear zones around colonies; however, there are several problems with previous methods such as undesired contamination in the fume hood and difficulty in controlling the amount of PAH on the plates. In this study, we developed a modified screening method to address the drawbacks encountered with previous screening methods. A uniform white layer of PAHs was generated by spreading PAHs dissolved in volatile solvents over a surface of solidified agar medium, followed by the evaporation of the solvents. An inoculation was then performed by spreading a molten agar medium containing microbial samples over the solidified agar medium with a PAH layer. Subsequently, the white PAH layer migrated to the surface of the molten agar medium. This essential modification enabled us not only to solve problems of the previous screening methods but also to prepare an agar plate with a PAH layer without a complicated experimental scheme in the anaerobic chamber. After solidification of the molten agar medium and incubation of the plates, clear zones were successfully detected around colonies with aerobic and anaerobic PAH-degrading microbial cultures.

  19. FROM ENERGY IMPROVEMENT TO ACCURACY ENHANCEMENT:IMPROVEMENT OF PLATE BENDING ELEMENTS BY THE COMBINED HYBRID METHOD

    Institute of Scientific and Technical Information of China (English)

    Xiao-ping Xie

    2004-01-01

    By following the geometric point of view in mechanics, a novel expression of the combined hybrid method for plate bending problems is introduced to clarify its intrinsic mechanism of enhancing coarse-mesh accuracy of conforming or nonconforming plate elements.By adjusting the combination parameter α∈ (0, 1) and adopting appropriate bending moments modes, reduction of energy error for the discretized displacement model leads to enhanced numerical accuracy. As an application, improvement of Adini's rectangle is discussed. Numerical experiments show that the combined hybrid counterpart of Adini's element is capable of attaining high accuracy at coarse meshes.

  20. Electroless plating of PVC plastic through new surface modification method applying a semi-IPN hydrogel film

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Ming-Qiu, E-mail: mqwang1514@163.com; Yan, Jun; Du, Shi-Guo; Li, Hong-Guang

    2013-07-15

    A novel palladium-free surface activation process for electroless nickel plating was developed. This method applied a semi-Interpenetrating Polymer Network (semi-IPN) hydrogel film to modify the poly(vinyl chloride) (PVC) surface by chemical bonds. The activation process involved the formation of semi-IPN hydrogel film on the PVC surface and the immobilization of catalyst for electroless plating linking to the pretreated substrate via N-Ni chemical bond. The hydrogel layer was used as the chemisorption sites for nickel ions, and the catalyst could initiate the subsequent electroless nickel plating onto the PVC surface. Finally, a Ni–P layer was deposited on the nickel-activated PVC substrate by electroless plating technique. The composition and morphology of nickel-plated PVC foils were characterized by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), energy dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD). The results of SEM and XRD show that a compact and continuous Ni–P layer with amorphous nickel phase is formed on the PVC surface. EDS shows that the content of the nickel and the phosphorus in the deposits is 89.4 wt.% and 10.6 wt.%, respectively.

  1. INTEGRAL EQUATION METHOD'S APPLICATION IN HOLE-EDGE STRESS OF COMPOSITE MATERIAL PLATE WITH DIFFERENT SHAPED HOLES

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The strength of composite plate with different hole-shapes is always one of the most important but complicated issues in the application of the composite material. The holes will lead to mutations and discontinuity to the structure. So the hole-edge stress concentration is always a serious phenomenon. And the phenomenon makes the structure strength decrease very quickly to form dangerous weak points. Most partial damage begins from these weak points. According to the complex variable functions theory, the accurate boundary condition of composite plate with different hole-shapes is founded by conformal mapping method to settle the boundary condition problem of complex hole-shapes. Composite plate with commonly hole-shapes in engineering is studied by several complex variable stress function. The boundary integral equations are founded based on exact boundary conditions. Then the exact hole-edge stress analytic solution of composite plate with rectangle holes and wing manholes is resolved. Both of offset axis loadings and its influences on the stress concentration coefficient of the hole-edge are discussed. And comparisons of different loads along various offset axis on the hole-edge stress distribution of orthotropic plate with rectangle hole or wing manhole are made. It can be concluded that hole-edge with continuous variable curvatures might help to decrease the stress concentration coefficient; and smaller angle of outer load and fiber can decrease the stress peak value.

  2. Electroless plating of PVC plastic through new surface modification method applying a semi-IPN hydrogel film

    Science.gov (United States)

    Wang, Ming-Qiu; Yan, Jun; Du, Shi-Guo; Li, Hong-Guang

    2013-07-01

    A novel palladium-free surface activation process for electroless nickel plating was developed. This method applied a semi-Interpenetrating Polymer Network (semi-IPN) hydrogel film to modify the poly(vinyl chloride) (PVC) surface by chemical bonds. The activation process involved the formation of semi-IPN hydrogel film on the PVC surface and the immobilization of catalyst for electroless plating linking to the pretreated substrate via Nsbnd Ni chemical bond. The hydrogel layer was used as the chemisorption sites for nickel ions, and the catalyst could initiate the subsequent electroless nickel plating onto the PVC surface. Finally, a Ni-P layer was deposited on the nickel-activated PVC substrate by electroless plating technique. The composition and morphology of nickel-plated PVC foils were characterized by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), energy dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD). The results of SEM and XRD show that a compact and continuous Ni-P layer with amorphous nickel phase is formed on the PVC surface. EDS shows that the content of the nickel and the phosphorus in the deposits is 89.4 wt.% and 10.6 wt.%, respectively.

  3. Thermal Effects on Vibration and Control of Piezocomposite Kirchhoff Plate Modeled by Finite Elements Method

    Directory of Open Access Journals (Sweden)

    M. Sanbi

    2015-01-01

    Full Text Available Theoretical and numerical results of the modeling of a smart plate are presented for optimal active vibration control. The smart plate consists of a rectangular aluminum piezocomposite plate modeled in cantilever configuration with surface bonded thermopiezoelectric patches. The patches are symmetrically bonded on top and bottom surfaces. A generic thermopiezoelastic theory for piezocomposite plate is derived, using linear thermopiezoelastic theory and Kirchhoff assumptions. Finite element equations for the thermopiezoelastic medium are obtained by using the linear constitutive equations in Hamilton’s principle together with the finite element approximations. The structure is modelled analytically and then numerically and the results of simulations are presented in order to visualize the states of their dynamics and the state of control. The optimal control LQG-Kalman filter is applied. By using this model, the study first gives the influences of the actuator/sensor pair placement and size on the response of the smart plate. Second, the effects of thermoelastic and pyroelectric couplings on the dynamics of the structure and on the control procedure are studied and discussed. It is shown that the effectiveness of the control is not affected by the applied thermal gradient and can be applied with or without this gradient at any time of plate vibrations.

  4. A practical method for the determination of total selenium in environmental samples using isotope dilution-hydride generation-inductively coupled plasma-mass spectrometry

    Science.gov (United States)

    Kleckner, Amy E.; Kakouros, Evangelos; Stewart, A. Robin

    2017-01-01

    A safe, practical, and accurate method for the determination of selenium (Se) in range of environmental samples was developed. Small sample masses, 5–20 mg, were amended with 82Se enriched isotope for the isotope dilution (ID), preceding a multi-step wet digestion with nitric acid (HNO3) and hydrogen peroxide (H2O2). Samples were incubated in an autoclave for 3 h at 20 psi and 126°C. Digestates were subsequently reduced with concentrated hydrochloric acid to Se(IV) the most favorable valence for hydride generation (HG). The solutions were then analyzed on an ICP-MS equipped with Flow Injection system (FIAS-400). Polyatomic, isobaric, and background interferences were removed through the use of HG and ID with an 82Se enriched isotope spike. Recoveries for certified reference materials were determined and averaged 96% for biological tissues (NRCC DOLT3, DOLT4, DORM2, TORT2, and TORT3, and NIST 2976) and 108% for estuarine sediment (NRCC PACS2) with an average coefficient of variation for replicate measurements of ∼ 3.5%. Limit of detection was 0.13 ng Se g−1 dry weight or 0.19 ng Se L−1. This method can be broadly applied to biological tissues, sediments, suspended particulates, and water samples with minimal modifications making this method highly useful for assessing the ecotoxicology of total Se in aquatic ecosystems.

  5. Comparison of polymerase chain reaction methods and plating for analysis of enriched cultures of Listeria monocytogenes when using the ISO11290-1 method.

    Science.gov (United States)

    Dalmasso, Marion; Bolocan, Andrei Sorin; Hernandez, Marta; Kapetanakou, Anastasia E; Kuchta, Tomáš; Manios, Stavros G; Melero, Beatriz; Minarovičová, Jana; Muhterem, Meryem; Nicolau, Anca Ioana; Rovira, Jordi; Skandamis, Panagiotis N; Stessl, Beatrix; Wagner, Martin; Jordan, Kieran; Rodríguez-Lázaro, David

    2014-03-01

    Analysis for Listeria monocytogenes by ISO11290-1 is time-consuming, entailing two enrichment steps and subsequent plating on agar plates, taking five days without isolate confirmation. The aim of this study was to determine if a polymerase chain reaction (PCR) assay could be used for analysis of the first and second enrichment broths, saving four or two days, respectively. In a comprehensive approach involving six European laboratories, PCR and traditional plating of both enrichment broths from the ISO11290-1 method were compared for the detection of L. monocytogenes in 872 food, raw material and processing environment samples from 13 different dairy and meat food chains. After the first and second enrichments, total DNA was extracted from the enriched cultures and analysed for the presence of L. monocytogenes DNA by PCR. DNA extraction by chaotropic solid-phase extraction (spin column-based silica) combined with real-time PCR (RTi-PCR) was required as it was shown that crude DNA extraction applying sonication lysis and boiling followed by traditional gel-based PCR resulted in fewer positive results than plating. The RTi-PCR results were compared to plating, as defined by the ISO11290-1 method. For first and second enrichments, 90% of the samples gave the same results by RTi-PCR and plating, whatever the RTi-PCR method used. For the samples that gave different results, plating was significantly more accurate for detection of positive samples than RTi-PCR from the first enrichment, but RTi-PCR detected a greater number of positive samples than plating from the second enrichment, regardless of the RTi-PCR method used. RTi-PCR was more accurate for non-food contact surface and food contact surface samples than for food and raw material samples especially from the first enrichment, probably because of sample matrix interference. Even though RTi-PCR analysis of the first enrichment showed less positive results than plating, in outbreak scenarios where a rapid result is

  6. 3M Petrifilm Staph Express Count plate method for the enumeration of Staphylococcus aureus in selected dairy foods: collaborative study.

    Science.gov (United States)

    Silbernagel, Karen M; Jechorek, Robert P; Carver, Charles N; Horter, Barbara L; Lindberg, Kathryn G

    2003-01-01

    The 3M Petrifilm Staph Express Count plate method was compared with AOAC Official Method 975.55 for the enumeration of Staphylococcus aureus in selected foods. Five foods--ice cream, raw milk, yogurt, whey powder, and cheese--were analyzed for S. aureus by 12 collaborating laboratories. For each food tested, the collaborators received 8 blind test samples consisting of a control sample, a low inoculation level, a medium inoculation level, and a medium inoculation level with background flora, each in duplicate. The mean log10 counts for the methods were comparable for all 5 foods. The repeatability and reproducibility variances of the 24 h Petrifilm Staph Express Count plate method were similar to those of the 72 h standard method.

  7. Characterisation of the dilute HCl extraction method for the identification of metal contamination in Antarctic marine sediments.

    Science.gov (United States)

    Snape, I; Scouller, R C; Stark, S C; Stark, J; Riddle, M J; Gore, D B

    2004-11-01

    A regional survey of potential contaminants in marine or estuarine sediments is often one of the first steps in a post-disturbance environmental impact assessment. Of the many different chemical extraction or digestion procedures that have been proposed to quantify metal contamination, partial acid extractions are probably the best overall compromise between selectivity, sensitivity, precision, cost and expediency. The extent to which measured metal concentrations relate to the anthropogenic fraction that is bioavailable is contentious, but is one of the desired outcomes of an assessment or prediction of biological impact. As part of a regional survey of metal contamination associated with Australia's past waste management activities in Antarctica, we wanted to identify an acid type and extraction protocol that would allow a reasonable definition of the anthropogenic bioavailable fraction for a large number of samples. From a kinetic study of the 1 M HCl extraction of two Certified Reference Materials (MESS-2 and PACS-2) and two Antarctic marine sediments, we concluded that a 4 h extraction time allows the equilibrium dissolution of relatively labile metal contaminants, but does not favour the extraction of natural geogenic metals. In a regional survey of 88 marine samples from the Casey Station area of East Antarctica, the 4 h extraction procedure correlated best with biological data, and most clearly identified those sediments thought to be contaminated by runoff from abandoned waste disposal sites. Most importantly the 4 h extraction provided better definition of the low to moderately contaminated locations by picking up small differences in anthropogenic metal concentrations. For the purposes of inter-regional comparison, we recommend a 4 h 1 M HCl acid extraction as a standard method for assessing metal contamination in Antarctica.

  8. Antimicrobial Susceptibility of Flavobacterium psychrophilum from Chilean Salmon Farms and their Epidemiological Cut-off Values using Agar Dilution and Disk Diffusion Methods

    Directory of Open Access Journals (Sweden)

    Claudio D Miranda

    2016-11-01

    Full Text Available Flavobacterium psychrophilum is the most important bacterial pathogen for freshwater farmed salmonids in Chile. The aims of this study were to determine the susceptibility to antimicrobials used in fish farming of Chilean isolates and to calculate their epidemiological cut-off (COWT values. A number of 125 Chilean isolates of F. psychrophilum were isolated from reared salmonids presenting clinical symptoms indicative of flavobacteriosis and their identities were confirmed by 16S rRNA polymerase chain reaction. Susceptibility to antibacterials was tested on diluted Mueller-Hinton by using an agar dilution MIC method and a disk diffusion method. The COWT values calculated by Normalised Resistance Interpretation (NRI analysis allow isolates to be categorized either as wild-type fully susceptible (WT or as manifesting reduced susceptibility (NWT. When MIC data was used, NRI analysis calculated a COWT of ≤ 0.125 μg mL-1, ≤ 2 μg mL-1 and ≤ 0.5 μg mL-1 for amoxicillin, florfenicol and oxytetracycline, respectively. For the quinolones, the COWT were ≤1 μg mL-1, ≤ 0.5 μg mL-1 and ≤ 0.125 μg mL-1 for oxolinic acid, flumequine and enrofloxacin respectively. The disc diffusion data sets obtained in this work were extremely diverse and were spread over a wide range. For the quinolones there was a close agreement between the frequencies of NWT isolates calculated using MIC and disc data. For oxolinic acid, flumequine and enrofloxacin the frequencies were 45, 39 and 38% using MIC data, and 42, 41 and 44%, when disc data were used. There was less agreement with the other antimicrobials, because NWT frequencies obtained using MIC and disc data respectively, were 24% and 10% for amoxicillin, 8% and 2% for florfenicol and 70% and 64% for oxytetracycline. Considering that the MIC data was more precise than the disc diffusion data, MIC determination would be the preferred method for susceptibility testing for this species and the NWT frequencies

  9. Simple and rapid analytical method for detection of amino acids in blood using blood spot on filter paper, fast-GC/MS and isotope dilution technique.

    Science.gov (United States)

    Kawana, Shuichi; Nakagawa, Katsuhiro; Hasegawa, Yuki; Yamaguchi, Seiji

    2010-11-15

    A simple and rapid method for quantitative analysis of amino acids, including valine (Val), leucine (Leu), isoleucine (Ile), methionine (Met) and phenylalanine (Phe), in whole blood has been developed using GC/MS. In this method, whole blood was collected using a filter paper technique, and a 1/8 in. blood spot punch was used for sample preparation. Amino acids were extracted from the sample, and the extracts were purified using cation-exchange resins. The isotope dilution method using ²H₈-Val, ²H₃-Leu, ²H₃-Met and ²H₅-Phe as internal standards was applied. Following propyl chloroformate derivatization, the derivatives were analyzed using fast-GC/MS. The extraction recoveries using these techniques ranged from 69.8% to 87.9%, and analysis time for each sample was approximately 26 min. Calibration curves at concentrations from 0.0 to 1666.7 μmol/l for Val, Leu, Ile and Phe and from 0.0 to 333.3 μmol/l for Met showed good linearity with regression coefficients=1. The method detection limits for Val, Leu, Ile, Met and Phe were 24.2, 16.7, 8.7, 1.5 and 12.9 μmol/l, respectively. This method was applied to blood spot samples obtained from patients with phenylketonuria (PKU), maple syrup urine disease (MSUD), hypermethionine and neonatal intrahepatic cholestasis caused by citrin deficiency (NICCD), and the analysis results showed that the concentrations of amino acids that characterize these diseases were increased. These results indicate that this method provides a simple and rapid procedure for precise determination of amino acids in whole blood. Copyright © 2010 Elsevier B.V. All rights reserved.

  10. The Optimizing Conditions by Taguchi Method for Fabricating Semi-Solid Al-Zn-Mg Alloy Slurry by Cooling Plate Method

    Science.gov (United States)

    Shim, Sung-Yong; Park, Hyung-Won; Jeong, In-Sang; Lim, Su-Gun

    In order to optimize the condition for the semi-solid Al-Zn-Mg aluminium alloy fabricated by cooling plate method, the Taguchi design was used. The cooling plate method effectively separating the grains formed from the mold wall can be used to form a semi-solid material by flowing molten metal over an inclined Cu plate and casting in a mold for the near-net shape component. In Taguchi's design method, the higher signal vs noise (S/N) ratio the better. Therefore, the manufacturing conditions were arranged as a table of orthogonal arrays (L9(34)), and the influence of two factors, pouring temperature and cooling plate angle, was examined. From the observed microstructures, the grain size and aspect ratio were measured by image analyzer. The results indicated that the pouring temperature exerts the main effect on the spherical microstructures since the S/N ratio, which is the sensibility of the surrounding environment, was the highest. The optimum condition for the Al-Zn-Mg alloy was a cooling plate angle of 40° and a pouring temperature of 680°C. The grain size and aspect ratio were 70 μm and 1.3, respectively.

  11. A high-throughput microtiter plate based method for the determination of peracetic acid and hydrogen peroxide.

    Directory of Open Access Journals (Sweden)

    Karson S Putt

    Full Text Available Peracetic acid is gaining usage in numerous industries who have found a myriad of uses for its antimicrobial activity. However, rapid high throughput quantitation methods for peracetic acid and hydrogen peroxide are lacking. Herein, we describe the development of a high-throughput microtiter plate based assay based upon the well known and trusted titration chemical reactions. The adaptation of these titration chemistries to rapid plate based absorbance methods for the sequential determination of hydrogen peroxide specifically and the total amount of peroxides present in solution are described. The results of these methods were compared to those of a standard titration and found to be in good agreement. Additionally, the utility of the developed method is demonstrated through the generation of degradation curves of both peracetic acid and hydrogen peroxide in a mixed solution.

  12. A high-throughput microtiter plate based method for the determination of peracetic acid and hydrogen peroxide.

    Science.gov (United States)

    Putt, Karson S; Pugh, Randall B

    2013-01-01

    Peracetic acid is gaining usage in numerous industries who have found a myriad of uses for its antimicrobial activity. However, rapid high throughput quantitation methods for peracetic acid and hydrogen peroxide are lacking. Herein, we describe the development of a high-throughput microtiter plate based assay based upon the well known and trusted titration chemical reactions. The adaptation of these titration chemistries to rapid plate based absorbance methods for the sequential determination of hydrogen peroxide specifically and the total amount of peroxides present in solution are described. The results of these methods were compared to those of a standard titration and found to be in good agreement. Additionally, the utility of the developed method is demonstrated through the generation of degradation curves of both peracetic acid and hydrogen peroxide in a mixed solution.

  13. Application of the HHT Method to the Non-contact Thickness Measurement of an Axially Moving Thin Plate

    Science.gov (United States)

    Wu, Yangfang; Lu, Qianqian; Xia, Chunlin; Ding, Fan

    2016-06-01

    Non-contact thickness measuring systems can be found in a wide spectrum of technologies. In this paper, Hilbert-Huang transform method is used to analyze the real time signals of a measuring system which includes two round conveyor strings carrying a thin plate, a solar wafer as a sample under test. The vibrations of moving strings and the plate, which are sensitive to moving speed and initial tension in the string, are introduced briefly; the relevant analyses should be helpful for the system design. Using EMD-based time-domain filtering and complementary method, thickness variations and error bands are estimated for different cases. The results show that HHT method as an adaptive time-frequency method, should be potential in measurement engineering applications.

  14. Stability-Indicating UPLC Method for Tramadol HCl Impurities in the Tramadol Injection after Dilution by Infusion Fluids (5% Dextrose and 0.9% Sodium Chloride).

    Science.gov (United States)

    Binnor, Anil K; Mukkanti, Khagga; Suryanarayana, Mulukutla V; Roy, Sunilendu B

    2013-01-01

    A novel, rapid, and sensitive ultra-performance liquid chromatography (UPLC) method has been developed and validated as per ICH guidelines for the determination of tramadol HCl impurities in the tramadol HCl injection after reconstitution by infusion fluids (5% dextrose and 0.9% sodium chloride). The tramadol HCl injection is for the treatment of patients with moderate-to-severe pain. The stability of the reconstituted solution is critical before intravenous injection. The literature search resulted in few published articles on assays of tramadol in infusion fluids by conventional HPLC. No attempts have yet been made to determine the impurities in infusion fluids, as the concentration of tramadol after reconstitution is extremely low (0.4 mg/mL) and that of impurities is even lower. The proposed method is novel as it allows the quantitation of the impurities of tramadol HCl and is based on modern chromatographic techniques like UPLC. The method was developed using the Waters Acquity BEH C18 column with a mobile phase consisting of a gradient mixture of solvent A (trifluroacetic acid buffer) and solvent B (methanol: acetonitrile). The model stability study was designed by diluting the tramadol HCl injection in the 5% dextrose injection and 0.9% sodium chloride injection. Each mixture was kept under storage at room temperature (25 ± 2°C) for testing at initial, 2, 4, 8, 12, 18 & 24 hours. The validation study illustrates that the proposed method is suitable for the determination of tramadol and its impurities. The proposed method makes use of the LC-MS-compatible mobile phase. It can be useful for the determination of tramadol HCl and its impurities in plasma samples and other pharmaceutical dosage forms.

  15. Impact Response of Cantilever Fiber Metal Laminate (FML Plates Using a Coupled Analytical-Numerical Method

    Directory of Open Access Journals (Sweden)

    Faramarz Ashenai Ghasemi

    2013-05-01

    Full Text Available In this study, dynamic response of cantilever Fiber Metal Laminate (FML plates subjected to the impact of a large mass is studied. Aluminum (Al sheets are placed instead of some Fiber Reinforced Plastic (FRP layers. The effect of the Al layers on contact force and deflection of the plates is investigated by considering the interaction between the impactor and the target in the impact analysis. A two degrees-of-freedom system consisting of springs-masses and finite element modeling of the ABAQUS/Explicit software were employed to model the interaction between the impactor and the target. The results indicate that some parameters like the layer sequence, mass and velocity of the impactor, mass of the target are important factors which affect the impact response of the plates.

  16. Development and validation of a stable-isotope dilution liquid chromatography-tandem mass spectrometry method for the determination of bisphenols in ready-made meals.

    Science.gov (United States)

    Regueiro, Jorge; Wenzl, Thomas

    2015-10-01

    Due to their growing consumption, ready-made meals are a major dietary component for many people in today's society, representing an important potential route of human exposure to several food contaminants. The recent restrictions in the use of bisphenol A have led the plastic industry to look for alternative chemicals, most of them belonging to the same family of p,p'-bisphenols. The aim of the current work was to develop and validate a method based on stable-isotope dilution liquid chromatography-tandem mass spectrometry for the analysis of bisphenol A and its main analogs - bisphenol S, 4,4'-sulfonylbis(2-methylphenol), bisphenol F, bisphenol E, bisphenol B, bisphenol Z, bisphenol AF, bisphenol AP, tetrabromobisphenol A and bisphenol P - in solid foodstuffs, and particularly in ready-made meals. Extraction was carried out by ultrasound-assisted extraction after sample disruption with sand. A selective solid-phase extraction procedure was then applied to reduce potential matrix interferences. Derivatization of bisphenols with pyridine-3-sulfonyl chloride increased their ionization efficiency by electrospray ionization. Validation of the proposed method was performed in terms of selectivity, matrix effects, linearity, precision, measurement uncertainty, trueness and limits of detection. Satisfactory repeatability and intermediate precision were obtained; the related relative standard deviations were ≤7.8% and ≤10%, respectively. The relative expanded uncertainty (k=2) was below 17% for all bisphenol analogs and the trueness of the method was demonstrated by spike recovery experiments. Low limits of detection, in the range from 0.025μgkg(-1) to 0.140μgkg(-1), were obtained for all compounds. To demonstrate the applicability of the proposed method, it was eventually applied to several ready-made meals purchased from different supermarkets in Belgium.

  17. A new diagnostic method for separating airborne and structureborne noise radiated by plates with applications for propeller driven aircraft

    Science.gov (United States)

    Mcgary, Michael C.

    1988-01-01

    The anticipated application of advanced turboprop propulsion systems is expected to increase the interior noise of future aircraft to unacceptably high levels. The absence of technically and economically feasible noise source-path diagnostic tools has been a prime obstacle in the development of efficient noise control treatments for propeller-driven aircraft. A new diagnostic method that permits the separation and prediction of the fully coherent airborne and structureborne components of the sound radiated by plates or thin shells has been developed. Analytical and experimental studies of the proposed method were performed on an aluminum plate. The results of the study indicate that the proposed method could be used in flight, and has fewer encumbrances than the other diagnostic tools currently available.

  18. Standard Test Method for Water Penetration of Flat Plate Solar Collectors by Uniform Static Air Pressure Difference

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    1986-01-01

    1.1 This test method covers the determination of the resistance of flat plate solar collectors to water penetration when water is applied to their outer surfaces with a static air pressure at the outer surface higher than the pressure at the interior of the collector. 1.2 This test method is applicable to any flat plate solar collector. 1.3 The proper use of this test method requires a knowledge of the principles of pressure and deflection measurement. 1.4 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only. 1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. Specific precautionary information is contained in Section 6.

  19. Stable isotope dilution HILIC-MS/MS method for accurate quantification of glutamic acid, glutamine, pyroglutamic acid, GABA and theanine in mouse brain tissues.

    Science.gov (United States)

    Inoue, Koichi; Miyazaki, Yasuto; Unno, Keiko; Min, Jun Zhe; Todoroki, Kenichiro; Toyo'oka, Toshimasa

    2016-01-01

    In this study, we developed the stable isotope dilution hydrophilic interaction liquid chromatography with tandem mass spectrometry (HILIC-MS/MS) technique for the accurate, reasonable and simultaneous quantification of glutamic acid (Glu), glutamine (Gln), pyroglutamic acid (pGlu), γ-aminobutyric acid (GABA) and theanine in mouse brain tissues. The quantification of these analytes was accomplished using stable isotope internal standards and the HILIC separating mode to fully correct the intramolecular cyclization during the electrospray ionization. It was shown that linear calibrations were available with high coefficients of correlation (r(2)  > 0.999, range from 10 pmol/mL to 50 mol/mL). For application of the theanine intake, the determination of Glu, Gln, pGlu, GABA and theanine in the hippocampus and central cortex tissues was performed based on our developed method. In the region of the hippocampus, the concentration levels of Glu and pGlu were significantly reduced during reality-based theanine intake. Conversely, the concentration level of GABA increased. This result showed that transited theanine has an effect on the metabolic balance of Glu analogs in the hippocampus.

  20. Characterizing Soy Sauce Moromi Manufactured by High-Salt Dilute-State and Low-Salt Solid-State Fermentation Using Multiphase Analyzing Methods.

    Science.gov (United States)

    Zhang, Liqiang; Zhou, Rongqing; Cui, Ruiying; Huang, Jun; Wu, Chongde

    2016-10-14

    Present study was to characterize the physiochemical properties, free amino acids (FAAs), volatiles and microbial communities of various moromi, respectively sampled from different stages of high-salt dilute-state (HSDS) and low-salt solid-state (LSSS) fermentation, using multiphase analyzing methods. Phospholipid fatty acids (PLFA) analysis indicated that Gram-positive bacteria were dominant bacteria and fungi were principal microbes. For DGGE analysis, dominant microbes in moromi were mainly fell into Weissella, Tetragenococcus, Candida, Pichia, and Zygosaccharomyces. During fermentation, the dominant microbes shifted from nonhalophilic and less acid-tolerant species to halophilic and acid-tolerant species. Total of 15 FAAs and 44 volatiles were identified in moromi, mainly Glu, Asp, Tyr, and acids, alcohols, esters, aldehydes, respectively. Odor activity values analysis suggested that the final moromi of LSSS fermentation had more complicated odors than that of HSDS fermentation. Conclusively, technological parameters, microbial communities, raw materials and fermentation process may result in the discrepancy of HSDS and LSSS moromi.

  1. Estimation of fatigue evolution of aluminum alloy plated with electroless NI–CO–P by using electromagnetic impedance method

    Energy Technology Data Exchange (ETDEWEB)

    Kinoshita, Katsuyuki

    2015-02-01

    We have developed a method for detecting fatigue in aluminum alloys that is based on a applying a ferromagnetic electroless Ni–Co–P plating and then using an electromagnetic impedance (EMI) method to determine its permeability properties by measuring the high-frequency AC impedance of a coil sensor in the presence of a static magnetic field. The results obtained confirmed that this method can estimate the fatigue evolution of a specimen until the point at which the cumulative strain becomes saturated by using measurements obtained by the EMI method under tensile deformation and FEM analysis results. - Highlights: • Plating aluminum alloy with Ni–Co–P film increases its fatigue strength by 13−16%. • The tensile direction is the stress induced “hard axis” of the Ni–Co–P plating. • In-plane permeability determines the coil impedance for out-of-plane excitation. • This method can measure fatigue up to saturation of the substrate's residual strain.

  2. Preparation of standard mixtures of gas hydrocarbons in air by the diffusion dilution method; Preparacion de mezclas patrones de hidrocarburos gaseosos en aire por el metodo de dilucion por difusion

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, M. R.; Perez, M. M.

    1979-07-01

    An original diffusion system able to produce continuously gaseous samples is described. This system can generate samples with concentrations of benzene in air from 0.1 to 1 ppm a reproducible way. The diffusion dilution method used Is also studied. The use of this diffusion system has been extended to the preparation of binary mixtures (benzene-toluene). Whit a secondary dilution device is possible preparing these mixtures over a wide range of concentrations (0.11 to 0.04 ppm for benzene and 0.06 to 0.02 for toluene). (Author) 7 refs.

  3. Requirements and testing methods for surfaces of metallic bipolar plates for low-temperature PEM fuel cells

    Science.gov (United States)

    Jendras, P.; Lötsch, K.; von Unwerth, T.

    2017-03-01

    To reduce emissions and to substitute combustion engines automotive manufacturers, legislature and first users aspire hydrogen fuel cell vehicles. Up to now the focus of research was set on ensuring functionality and increasing durability of fuel cell components. Therefore, expensive materials were used. Contemporary research and development try to substitute these substances by more cost-effective material combinations. The bipolar plate is a key component with the greatest influence on volume and mass of a fuel cell stack and they have to meet complex requirements. They support bending sensitive components of stack, spread reactants over active cell area and form the electrical contact to another cell. Furthermore, bipolar plates dissipate heat of reaction and separate one cell gastight from the other. Consequently, they need a low interfacial contact resistance (ICR) to the gas diffusion layer, high flexural strength, good thermal conductivity and a high durability. To reduce costs stainless steel is a favoured material for bipolar plates in automotive applications. Steel is characterized by good electrical and thermal conductivity but the acid environment requires a high chemical durability against corrosion as well. On the one hand formation of a passivating oxide layer increasing ICR should be inhibited. On the other hand pitting corrosion leading to increased permeation rate may not occur. Therefore, a suitable substrate lamination combination is wanted. In this study material testing methods for bipolar plates are considered.

  4. Three-dimensional stress and free vibration analyses of functionally graded plates with circular holes by the use of the graded finite element method

    Science.gov (United States)

    Asemi, K.; Ashrafi, H.; Shariyat, M.

    2016-07-01

    Static and free vibration analyses of plates with circular holes are performed based on the three-dimensional theory of elasticity. The plates are made of a functionally graded material (FGM), and the volume fractions of the constituent materials vary continuously across the plate. The effective properties of the FGM plate are estimated by using the Mori-Tanaka homogenization method. A graded finite element method based on the Rayleigh-Ritz energy formulation is used to solve the problem. Effects of different volume fractions of the materials and hole sizes on the behavior of FGM plates under uniaxial tension are investigated. Natural frequencies of a fully clamped FGM plate with a circular cutout are derived. The results obtained are compared with available experimental data.

  5. Comparison of 3M Petrifilm Aerobic Count Plates to standard plating methodology for use with AOAC antimicrobial efficacy methods 955.14, 955.15, 964.02, and 966.04 as an alternative enumeration procedure: collaborative study.

    Science.gov (United States)

    Nelson, Maria T; LaBudde, Robert A; Tomasino, Stephen F; Pines, Rebecca M

    2013-01-01

    A multilaboratory study was conducted to determine the equivalence of the 3M Petrifilm Aerobic Count Plate and standard plating methodology for measuring viable bacteria and spores recovered from hard-surface carriers (stainless steel and porcelain), also known as "control carrier counts," used in AOAC antimicrobial efficacy test methods. Six laboratories participated in the study in which carriers inoculated with Staphylococcus aureus, Pseudomonas aeruginosa, Salmonella enterica, and spores of Bacillus subtilis were evaluated using 3M Petrifilm Aerobic Count (AC) plates and standard plating side-by-side. The data were analyzed using a matched-pair t-test to determine the between-method effect with confidence intervals. For all test organisms pooled across all laboratories, the mean difference in log10 concentration between the standard plate count method and 3M Petrifilm AC Plates was -0.012, with a 95% confidence interval of (-0.090, +0.066), which was well within the -0.5, +0.5 interval established as the acceptance criterion. The between-carrier SD averaged 0.139; the between-replicate SD was 0.050. The carrier reproducibility, given that a single replicate per carrier is done, was estimated to be 0.148. Although differences were seen in the final concentrations of the test organisms among laboratories, there were no statistical differences between the enumeration methods. Based on the results from this study, 3M Petrifilm AC Plates are equivalent to standard plating methodology and can be used as an alternative procedure for the enumeration of test organisms used in AOAC Methods 955.14, 955.15, 964.02, and 966.04.

  6. Evaluation of Petrifilm™ Select E. coli Count Plate medium to discriminate antimicrobial resistant Escherichia coli

    Directory of Open Access Journals (Sweden)

    Jensen Lars

    2008-09-01

    Full Text Available Abstract Background Screening and enumeration of antimicrobial resistant Escherichia coli directly from samples is needed to identify emerging resistant clones and obtain quantitative data for risk assessment. Aim of this study was to evaluate the performance of 3M™ Petrifilm™ Select E. coli Count Plate (SEC plate supplemented with antimicrobials to discriminate antimicrobial-resistant and non-resistant E. coli. Method A range of E. coli isolates were tested by agar dilution method comparing the Minimal Inhibitory Concentration (MIC for eight antimicrobials obtained by Mueller-Hinton II agar, MacConkey agar and SEC plates. Kappa statistics was used to assess the levels of agreement when classifying strains as resistant, intermediate or susceptible. Results SEC plate showed that 74% of all strains agreed within ± 1 log2 dilution when comparing MICs with Mueller-Hinton II media. High agreement levels were found for gentamicin, ampicillin, chloramphenicol and cefotaxime, resulting in a kappa value of 0.9 and 100% agreement within ± 1 log2 dilution. Significant variances were observed for oxytetracycline and sulphamethoxazole. Further tests showed that the observed discrepancy in classification of susceptibility to oxytetracycline by the two media could be overcome when a plate-dependent breakpoint of 64 mg/L was used for SEC plates. For sulphamethoxazole, SEC plates provided unacceptably high MICs. Conclusion SEC plates showed good agreement with Mueller-Hinton II agar in MIC studies and can be used to screen and discriminate resistant E. coli for ampicillin, cephalothin, streptomycin, chloramphenicol, cefotaxime and gentamicin using CLSI standardized breakpoints, but not for sulphamethoxazole. SEC plates can also be used to discriminate oxytetracycline-resistant E. coli if a plate-dependent breakpoint value of 64 mg/L is used.

  7. A New Activation Method for Electroless Metal Plating: Palladium Laden via Bonding with Self-Assembly Monolayers

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A new activation method has been developed for electroless copper plating on silicon wafer based on palladium chemisorption on SAMs of APTS without SnCl2 sensitization and roughening condition. A closely packed electroless copper film with strong adhesion is successfully fonned by AFM observation. XPS study indicates that palladium chemisorption occurred via palladium chloride bonding to the pendant amino group of the SAMs.

  8. Hybridizing pines with diluted pollen

    Science.gov (United States)

    Robert Z. Callaham

    1967-01-01

    Diluted pollens would have many uses by the tree breeder. Dilutions would be particularly advantageous in making many controlled pollinations with a limited amount of pollen. They also would be useful in artificial mass pollinations of orchards or single trees. Diluted pollens might help overcome troublesome genetic barriers to crossing. Feasibility o,f using diluted...

  9. First Comprehensive Evaluation of the M.I.C. Evaluator Device Compared to Etest and CLSI Reference Dilution Methods for Antimicrobial Susceptibility Testing of Clinical Strains of Anaerobes and Other Fastidious Bacterial Species

    Science.gov (United States)

    Turnbull, L.; Brosnikoff, C.; Cloke, J.

    2012-01-01

    The new M.I.C. Evaluator strip uses test methodology and the recording of results that are similar to those of Etest. For this first assessment, 102 clinical strains of anaerobic bacteria from 12 genera and 155 strains from 7 genera and 8 species of fastidious bacteria were tested by M.I.C. Evaluator, Etest, and agar dilution or broth microdilution as a reference standard. Ampicillin, amoxicillin, amoxicillin-clavulanate, cefotaxime, ciprofloxacin, erythromycin, imipenem, levofloxacin, metronidazole, penicillin, and tetracycline were tested depending on the species. Agar dilution for anaerobes was performed according to CLSI document M11-A7. For the fastidious bacteria, CLSI document M45-A2 was followed. For the anaerobes, essential and categorical agreement between M.I.C. Evaluator and Etest was >90%. Compared to agar dilution, essential agreement was low for both strip tests, and many very major errors were observed for metronidazole (13 to 14%) and penicillin (8 to 9%) with isolates from the Bacteroides fragilis group and Clostridium species. For fastidious species, essential agreements for M.I.C. Evaluator and Etest plus or minus one doubling dilution were >95%. Compared to broth microdilution, essential agreements were low (40 to 90%) plus or minus one dilution and were >90% plus or minus two dilutions, with high overall category agreement (CA). Major and minor errors were within established parameters for all strains tested. The M.I.C. Evaluator strips were equivalent to Etest for anaerobes and fastidious species. These observations require further investigation to determine which methods provide the most accurate MIC for clinical utility. The further evaluation of additional M.I.C. Evaluator agents will be performed as they become available. PMID:22238439

  10. Use of statistical modeling to reassess the performance standard for the AOAC use-dilution methods (955.15 and 964.02).

    Science.gov (United States)

    Tomasino, Stephen F; Parker, Albert E; Hamilton, Martin A

    2014-01-01

    The AOAC Use-dilution methods (UDM) 955.15 (Staphylococcus aureus) and 964.02 (Pseudomonas aeruginosa) are laboratory methods used to substantiate antimicrobial efficacy claims for liquid disinfectants on inanimate surfaces. The UDM is accepted by the U.S. Environmental Protection Agency for the purpose of product registration. To attain a hospital-level claim, testing against S. aureus and P. aeruginosa is required, and the product must pass against both microbes. Currently, the UDM's performance standard for a single 60-carrier test is the same for both microbes, and allows up to one positive carrier for the product to be considered as a pass. In this paper, the performance standards for these methods are reassessed using data from a 2009 five-laboratory collaborative study and a recently published statistical model. The reassessment focuses on the pass-error rate for ineffective products and the fail-error rate for highly effective products. The calculations indicate that the pass-error rate is between 9 and 24% and the fail-error rate between 18 and 23% when the current performance standard is used for a single test. For product registration, a smaller pass-error rate (1%) historically has been maintained by requiring that a disinfectant pass three UDM tests for each of the two microbes; however, the calculations also indicate that the fail-error rate is between 42 and 45%. This large fail-error rate is a compelling reason to consider a new performance standard for the two UDM methods, 955.15 (S. aureus) and 964.02 (P. aeruginosa). One alternative performance standard allows no more than six positive carriers out of 60 as a pass when using P. aeruginosa and no more than three positive carriers out of 60 when using S. aureus. In addition, the new performance standard requires that three UDM tests be performed with each of the two microbes, and the disinfectant must pass all six tests to be considered efficacious. The statistical calculations for this alternative

  11. Gel microbead cultivation with a subenrichment procedure can yield better bacterial cultivability from a seawater sample than standard plating method

    Science.gov (United States)

    Ji, Shiqi; Zhao, Rui; Yin, Qi; Zhao, Yuan; Liu, Chenguang; Xiao, Tian; Zhang, Xiaohua

    2012-03-01

    A gel microbead (GMD) cultivation method was employed to cultivate microorganisms from an amphioxus breeding zone in Qingdao, P. R. China. The culture results were compared with those by standard plating method. In the GMD-based method, the microcolony-forming GMDs were sorted by fluorescence-activated cell sorting (FACS). To further get pure cultures, a subsequent enrichment culture and a streaking purification procedure were conducted on marine R2A medium. Eighty bacterial strains isolated by the GMD-based method were randomly selected for sequencing. These isolates belonged to Alphaproteobacteria (33%), Gammaproteobacteria (44%), Bacteroidetes (11%), Actinobacteria (5%), Firmicutes (5%), Epsilonproteobacteria (1%), and Verrucomicrobia (1%), the last two groups being usually difficult to culture. The 16S rRNA gene sequences revealed a diverse community with 91.1%-100% of the bacterial rRNAs similarities. Thirteen strains were sharing 16S rRNA gene sequence which was less than 97% similar to any other rRNA genes currently deposited in TYP16S database. Seventy isolates derived from the standard plating method fell into 4 different taxonomic groups: Alphaproteobacteria (9%), Gammaproteobacteria (81%), Bacteroidetes (7%) and Firmicutes (3%) with a 16S rRNA gene sequence similarities between 95.8%-100%, in which only 3 strains were sharing 16S rRNA gene sequence of less than 97%. The results indicated that the GMD-based method with subenrichment culture yielded more taxonomic groups and more novel microbial strains, including members of previously rarely cultured groups, when compared with the standard plating method, and that this method markedly improved the bacterial cultivability.

  12. Evaluation of plate type fuel elements by eddy current test method; Avaliacao de combustiveis nucleares tipo placa pelo metodo de correntes parasitas

    Energy Technology Data Exchange (ETDEWEB)

    Frade, Rangel Teixeira

    2015-07-01

    Plate type fuel elements are used in MTR research nuclear reactors. The fuel plates are manufactured by assembling a briquette containing the fissile material inserted in a frame, with metal plates in both sides of the set, to act as a cladding. This set is rolled under controlled conditions in order to obtain the fuel plate. In Brazil, this type of fuel is manufactured by IPEN and used in the IEA-R1 reactor. After fabrication of three batches of fuel plates, 24 plates, one of them is taken, in order to verify the thickness of the cladding. For this purpose, the plate is sectioned and the thickness measurements are carried out by using optical microscopy. This procedure implies in damage of the plate, with the consequent cost. Besides, the process of sample preparation for optical microscopy analysis is time consuming, it is necessary an infrastructure for handling radioactive materials and there is a generation of radioactive residues during the process. The objective of this study was verify the applicability of eddy current test method for nondestructive measurement of cladding thickness in plate type nuclear fuels, enabling the inspection of all manufactured fuel plates. For this purpose, reference standards, representative of the cladding of the fuel plates, were manufactured using thermomechanical processing conditions similar to those used for plates manufacturing. Due to no availability of fuel plates for performing the experiments, the presence of the plate’s core was simulated using materials with different electrical conductivities, fixed to the thickness reference standards. Probes of eddy current testing were designed and manufactured. They showed high sensitivity to thickness variations, being able to separate small thickness changes. The sensitivity was higher in tests performed on the reference standards and samples without the presence of the materials simulating the core. For examination of the cladding with influence of materials simulating the

  13. A method for measuring skin friction drag on a flat plate in contaminated gas flows

    Science.gov (United States)

    Oetting, R. B.; Patterson, G. K.

    1984-01-01

    A technique for measuring friction drag in turbulent gas and gas/particle flows over flat plates is presented, and preliminary results are reported. A 0.25-in.-thick 72 x 6-in. Al plate is suspended by six horizontal support air bearings and four vertical alignment air bearings between fixed dummy plates and leading-edge and trailing-edge fairings in the 32-in.-high 48-in.-wide 11-ft-long test section of a closed-circuit atmospheric wind tunnel operating at 50-150 ft/sec. Particles of Fe and Al oxides of diameter 20-150 microns and density up to 0.3 lb particles per lb air are injected via a 6 x 0.167-in. nozzle; turbulence is induced by a roughened section of the leading-edge fairing; and friction drag is measured using a load-cell pressure transducer. Sample results are shown in a graph, demonstrating good agreement with theoretical drag calculations.

  14. Deformations between African and Euroasian plates estimated by methods of space geodesy - new result

    Science.gov (United States)

    Zeman, A.; Holesovsky, J.; Novotny, Z.; Hassan, K. A.; Abd El Monem, M. S.; Kostelecky, J.

    2009-12-01

    The contribution concerns with analysis of detailed information from the results of space geodesy (GPS) in the region of Mediterranean sea enclosing the results of till now not processed and published observations in quasipermanent network of the sites in Egypt. (It was made possible by agreement between the National Research Institute of Astronomy and Geophysics in Egypt and the Research Center of Earth Dynamics in Czech Republic). A main topic in WEGENER's project activities is observation of geodynamic processes of the European-Mediterranean region, northern Africa and Asia Minor, by (space) geodetic techniques. The geodynamic setting of the region is formed by the convergence of the three major lithosphere plates (Eurasia, Africa and Arabia). In the plate boundary zones a variety of subduction and collision processes are active. The cotribution contains actual results of processing of the observations in Egypt together with selected sites of permanent EPN network in region of eastern part of Mediterranean sea. Results of analyses confirm model presumption of mutual activities between African, Arabic and Euroasian plates.

  15. Semiquantitative determination of mesophilic, aerobic microorganisms in cocoa products using the Soleris NF-TVC method.

    Science.gov (United States)

    Montei, Carolyn; McDougal, Susan; Mozola, Mark; Rice, Jennifer

    2014-01-01

    The Soleris Non-fermenting Total Viable Count method was previously validated for a wide variety of food products, including cocoa powder. A matrix extension study was conducted to validate the method for use with cocoa butter and cocoa liquor. Test samples included naturally contaminated cocoa liquor and cocoa butter inoculated with natural microbial flora derived from cocoa liquor. A probability of detection statistical model was used to compare Soleris results at multiple test thresholds (dilutions) with aerobic plate counts determined using the AOAC Official Method 966.23 dilution plating method. Results of the two methods were not statistically different at any dilution level in any of the three trials conducted. The Soleris method offers the advantage of results within 24 h, compared to the 48 h required by standard dilution plating methods.

  16. Labile pools of Pb in vegetable-growing soils investigated by an isotope dilution method and its influence on soil pH.

    Science.gov (United States)

    Xie, Hong; Huang, Zhi-Yong; Cao, Ying-Lan; Cai, Chao; Zeng, Xiang-Cheng; Li, Jian

    2012-08-01

    Pollution of Pb in the surface of agricultural soils is of increasing concern due to its serious impact on the plant growth and the human health through the food chain. However, the mobility, activity and bioavailability of Pb rely mainly on its various chemical species in soils. In the present study, E and L values, the labile pools of isotopically exchangeable Pb, were estimated using the method of isotope dilution in three vegetable-growing soils. The experiments involved adding a stable enriched isotope ((206)Pb > 96%) to a soil suspension and to soils in which plants are subsequently grown, the labile pools of Pb were then estimated by measuring the isotopic composition of Pb in soil solutions and in the plant tissues, respectively. In addition, the correlation of E values and soil pH was investigated at the ranges of pH 4.5-7.0. The amount of labile Pb in soils was also estimated using different single chemical extractants and a modified BCR approach. The results showed that after spiking the enriched isotopes of (206)Pb (>96%) for 24 hours an equilibration of isotopic exchanges in soil suspensions was achieved, and the isotope ratios of (208)Pb/(206)Pb measured at that time was used for calculating the E(24 h) values. The labile pools of Pb by %E(24 h) values, ranging from 53.2% to 61.7% with an average 57%, were found to be significantly higher (p EDTA and the Σ(BCR) values extracted with the modified BCR approach are helpful to detect the labile pools of Pb in soils. In addition, the negative correlation between soil pH and the labile pools of Pb in soils may be useful for further remediation to reduce the bioavailability of Pb in contaminated soils.

  17. Tigecycline MIC testing by broth dilution requires use of fresh medium or addition of the biocatalytic oxygen-reducing reagent oxyrase to standardize the test method.

    Science.gov (United States)

    Bradford, Patricia A; Petersen, Peter J; Young, Mairead; Jones, C Hal; Tischler, Mark; O'Connell, John

    2005-09-01

    Tigecycline is a broad-spectrum glycylcycline antibiotic with activity against not only susceptible gram-positive and gram-negative pathogens but also strains that are resistant to many other antibiotics. In the process of determining quality control (QC) limits for the American Type Culture Collection reference strains for tigecycline, a number of inconsistencies in MICs were encountered which appeared to be related to the age of the Mueller-Hinton broth (MHB) medium used in the MIC testing. The objective of this study was to determine the cause of the discrepant MIC results between fresh and aged MHB. The MICs of tigecycline were determined in MHB that was either prepared fresh (reagent Oxyrase. When tested in fresh media, tigecycline was 2 to 3 dilutions more active against the CLSI-recommended QC strains compared to aged media (MICs of 0.03 to 0.25 and 0.12 to 0.5 mug/ml, respectively). Media aged under anaerobic conditions prior to testing or supplemented with Oxyrase resulted in MICs similar to those obtained in fresh medium (MICs of 0.03 to 0.12 and 0.03 to 0.25 mug/ml, respectively). Time-kill kinetics demonstrated a >3 log(10) difference in viable growth when tigecycline was tested in fresh or Oxyrase-supplemented MHB compared to aged MHB. High-pressure liquid chromatography analysis revealed the accumulation of an early peak (oxidative by-product of tigecycline) to be 3.5% in fresh media and 25.1% in aged media after 24 h and that addition of Oxyrase prevented the accumulation of this oxidized by-product. These results suggested that the activity of tigecycline was affected by the amount of dissolved oxygen in the media. The use of fresh MHB or supplementation with Oxyrase resulted in a more standardized test method for performing MIC tests with tigecycline.

  18. Fatigue Property of Open-Hole Steel Plates Influenced by Bolted Clamp-up and Hole Fabrication Methods

    Directory of Open Access Journals (Sweden)

    Zhi-Yu Wang

    2016-08-01

    Full Text Available Steel plates with open holes are commonly used in structural assemblies. The fatigue properties of such details are influenced by bolted clamp-up and hole fabrication methods. The fracture surface, stiffness degradation and fatigue life of test specimens are investigated in detail and compared with the contemporary test data. The analysis results show that the presence of draglines greatly influences the fatigue crack initiation at the open-hole cut by laser. The bolted clamp-up condition greatly enhances the stiffness and the fatigue life of the open-hole details. A discussion is also made from a comparison with the referred fatigue life of hole fabrication details, such as the influence of plate thickness and plasma cutting, drilling and oxy-fuel gas cutting, with the details studied herein. This work could enhance the understanding of the fatigue property and design of such details.

  19. An optimal open/closed-loop control method with application to a pre-stressed thin duralumin plate

    Science.gov (United States)

    Nadimpalli, Sruthi Raju

    The excessive vibrations of a pre-stressed duralumin plate, suppressed by a combination of open-loop and closed-loop controls, also known as open/closed-loop control, is studied in this thesis. The two primary steps involved in this process are: Step (I) with an assumption that the closed-loop control law is proportional, obtain the optimal open-loop control by direct minimization of the performance measure consisting of energy at terminal time and a penalty on open-loop control force via calculus of variations. If the performance measure also involves a penalty on closed-loop control effort then a Fourier based method is utilized. Step (II) the energy at terminal time is minimized numerically to obtain optimal values of feedback gains. The optimal closed-loop control gains obtained are used to describe the displacement and the velocity of open-loop, closed-loop and open/closed-loop controlled duralumin plate.

  20. Effect of Salt on Crystal Growth of Plate-like Alumina Particles by Molten-salt Method

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Bo Yeon; Lee, Yoon Joo; Kim, Soo Ryong; Kwon, Woo Teck; Shin, Dong Geun; Kim, Young Hee [Korea Institute of Ceramic Engineering and Technology, Seoul (Korea, Republic of); Choi, Duck Kyun [Hanyang University, Seoul (Korea, Republic of)

    2015-10-15

    Alumina powder have been expanded its application in industry and required to control its morphology such as powder size and aspect ratio of single particle. It can be synthesized by molten - salt method which is possible to obtain various shapes of ceramic particles by controlling the growth direction because each crystal face has different growth rate. In this study, various combinations of salts such as NaCl, Na{sub 2}SO{sub 4}, Na{sub 3}PO{sub 4} and their mixture were used for control the growth of plate like alumina particle from the initial stage of synthesis because salt having different ionic strength can control the growth direction of ceramic particle under its melting condition around 800-900 .deg. C, and growth behavior of plate-like alumina particle with different reaction conditions such as temperature and concentration on the crystal size and shape was studied.

  1. Experience of the Indirect Neutron Radiography Method Based on the X-ray Imaging Plate at CARR

    Science.gov (United States)

    Wei, Guohai; Han, Songbai; Wang, Hongli; He, Linfeng; Wang, Yu; Wu, Meimei; Liu, Yuntao; Chen, Dongfeng

    Indirect neutron radiography (INR) experiments by X-ray imaging plate were carried out at the China Advanced Research Reactor (CARR). The key experiment parameters were optimized, especially the exposure time of the neutron converter andimaging plate. The optimized total exposure time is 37.25 min, it is two-fifths of the timebased on the film method under the same experimental conditions. The qualitative and quantitativeinspections were tested with dummy nuclear fuel rods and a water temperaturesensor ofa motor vehicle. The spring in the sensor and the defects of the dummy fuel rod's pellets can be qualitatively detected. The thickness of the tape at one position on the cladding of the dummy nuclear fuel rodwas quantitatively calculated to be 9.57 layers with the relative error of ±4.3%.

  2. The reliability of the improved eN method for the transition prediction of boundary layers on a flat plate

    Institute of Scientific and Technical Information of China (English)

    SU CaiHong

    2012-01-01

    The transition criterion in the improved eN method is that transition would occur whenever the velocity amplitude of disturbance reaches 1%-2% of the free stream velocity,while in the conventional eN method,the N factor is an empirical factor.In this paper the reliability of this key assumption in the improved eN method is checked by results of transition prediction by using the Parabolized Stability Equations (PSE).Transition locations of an incompressible boundary layer and a hypersonic boundary layer at Mach number 6 on a flat plate are predicted by both the improved eN method and the PSE method.Results from both methods agree fairly well with each other,implying that the transition criterion proposed in the improved eN method is reliable.

  3. 2D numerical manifold method based on quartic uniform B-spline interpolation and its application in thin plate bending

    Institute of Scientific and Technical Information of China (English)

    温伟斌; 蹇开林; 骆少明

    2013-01-01

    A new numerical manifold (NMM) method is derived on the basis of quartic uniform B-spline interpolation. The analysis shows that the new interpolation function possesses higher-order continuity and polynomial consistency compared with the conven-tional NMM. The stiffness matrix of the new element is well-conditioned. The proposed method is applied for the numerical example of thin plate bending. Based on the prin-ciple of minimum potential energy, the manifold matrices and equilibrium equation are deduced. Numerical results reveal that the NMM has high interpolation accuracy and rapid convergence for the global cover function and its higher-order partial derivatives.

  4. Improved electroless plating method through ultrasonic spray atomization for depositing silver nanoparticles on multi-walled carbon nanotubes

    Science.gov (United States)

    Zhao, Qi; Xie, Ming; Liu, Yichun; Yi, Jianhong

    2017-07-01

    A novel method was developed to deposit nanosized silver particles on multi-walled carbon nanotubes (MWCNTs). The electroless plating of silver on MWCNTs accomplished in small solution drops generated by ultrasonic spray atomization, which inhibited excessive growth of silver particles and led to much more uniform nanometer grain-sized coatings. The results showed that pretreatment was essential for silver particles to deposit on the MWCNTs, and the electrolyte concentration and reaction temperature were important parameters which had a great influence on the morphology and structure of the silver coatings. Possible mechanisms of this method are also discussed in the paper.

  5. Flux balance analysis accounting for metabolite dilution.

    Science.gov (United States)

    Benyamini, Tomer; Folger, Ori; Ruppin, Eytan; Shlomi, Tomer

    2010-01-01

    Flux balance analysis is a common method for predicting steady-state flux distributions within metabolic networks, accounting for the growth demand for the synthesis of a predefined set of essential biomass precursors. Ignoring the growth demand for the synthesis of intermediate metabolites required for balancing their dilution leads flux balance analysis to false predictions in some cases. Here, we present metabolite dilution flux balance analysis, which addresses this problem, resulting in improved metabolic phenotype predictions.

  6. Measuring the Average Thickness of a Plate Using a Bayesian Method and Free Vibration Data

    Science.gov (United States)

    2011-09-01

    form, the model is constructed with the implicit assumption that the corrosion is uniform. A more detailed model that included details of the pitting ...PROCEDURE The test specimen was a 0.76m by 0.60m (30” by 24”, 5:4 aspect ratio), 1.55mm (1/16”) thick 6061 -T6 aluminum plate. The density was...considering corrosion effect.” Marine Struc- tures, 21(4):402 – 419. [3] T. Nakai, H. Matsushita, N. Yamamoto, and H. Arai, 2004. “Effect of pitting

  7. A novel combined method of osteosynthesis in treatment of tibial fractures: a comparative study on sheep with application of rod-through-plate fixator and bone plating.

    Science.gov (United States)

    Tralman, G; Andrianov, V; Arend, A; Männik, P; Kibur, R T; Nõupuu, K; Uksov, D; Aunapuu, M

    2013-04-01

    The study compares the efficiency of a new bone fixator combining periostal and intramedullary osteosynthesis to bone plating in treatment of tibial fractures in sheep. Experimental osteotomies were performed in the middle third of the left tibia. Animals were divided into two groups: in one group (four animals) combined osteosynthesis (rod-through-plate fixator, RTP fixator) was applied, and in the other group (three animals) bone plating was used. The experiments lasted for 10 weeks during which fracture union was followed by radiography, and the healing process was studied by blood serum markers reflecting bone turnover and by histological and immunohistochemical investigations. In the RTP fixator group, animals started to load body weight on the operated limbs the next day after the surgery, while in the bone plating group, this happened only on the seventh day. In the RTP fixator group, consolidation of fractures was also faster, as demonstrated by radiographical, histological, and immunohistochemical investigations and in part by blood serum markers for bone formation. It can be concluded that application of RTP fixation is more efficient than plate fixation in the treatment of experimental osteotomies of long bones in sheep.

  8. Comparison of a rapid ATP bioluminescence assay and standard plate count methods for assessing microbial contamination of consumers' refrigerators.

    Science.gov (United States)

    Chen, Fur-Chi; Godwin, Sandria L

    2006-10-01

    The feasibility of using an ATP bioluminescence assay for assessing microbial contamination of home refrigerators was evaluated and compared with the standard culture methods. Samples of refrigerator surfaces were collected from 123 households by swabbing an area of 100 cm2 on three locations in the refrigerator with premoisturized sterile swabs. Microbial contaminations were determined by aerobic plate count (APC; incubated at 35 degrees C for 48 h) and psychrotrophic plate count (PPC; incubated at 7 degrees C for 10 days) on plate count agar. The results were compared to the readings from the microbial ATP (mATP) bioluminescence assay. The correlation coefficient (r) between mATP and PPC (r = 0.851) was slightly higher than that between mATP and APC (r = 0.823). Our results indicated a potential discrepancy in the population of mesophilic and psychrotrophic bacteria in the refrigerator samples. Nevertheless, mATP appeared to be a reliable indication of the average of APC and PPC (r = 0.895). The mATP bioluminescence assay would provide a rapid and convenient test for researchers in field studies to assess microbial contamination in refrigerators.

  9. The Cavitation With Plate Transducer And Non Cavitation With Knob Transducer By Manihot Utilissima Fermentation The Potential Hydrogen Ph Method

    Directory of Open Access Journals (Sweden)

    Syamsul Arifin

    2015-08-01

    Full Text Available Abstract Manihot M. utilissima fermentation is popular foods and drinks for Indonesia people but it fermented foods 24 hours per day will breed fungi and anaerobic bacteriae so it will make it into acidic foods and alcoholic beverages. Ultrasonic 48 kHz 5 Vpp 1 VDC with functional generator and of the two models of transducers will have two different phenomena on M. utilissima fermentation. Methods Model-1. Radiation ultrasonic transducer plate or Flat of piezoelectric speakers2 were applied with transducers M. utilissima dipped in a test tube. Model-2. Knob or small ball ultrasonic transducer 12 balls were applied with transducers of tin knob which was connected to the copper wire2 and piezoelectricspeakers were dipped into the media M. utilissima in a test tube. After ultrasonic radiation fluid liquid from two models of transducers measured total acid in M. utilissima fermentation liquid by paper indicators of potential Hydrogen pH. The conclusion of this study can predict different phenomena namely the transducer plate of the initial pH value-acid fermentation M. utilissima can change increases the pH-value end of the base which means that the transducer plate has a cavitation phenomenon and media M. utilissima lead to the delicious food but on transducer knob that the initial pH value-acid fermentation M. utilissima will decrease more acid value so that have no phenomenon of cavitation and the media will lead M. utilissima to be alcoholic foods.

  10. Rhodium platings – experimental study

    Directory of Open Access Journals (Sweden)

    R. Rudolf

    2013-07-01

    Full Text Available Modern rhodium plating solutions are based on either sulphate or phosphate. Although in theory there are four possible combinations, in practice only three different rhodium electrolytes are used. These are based on dilutions of rhodium sulphate or phosphate concentrates with added sulphuric or phosphoric acid. These processes are be discussed in this paper with a demonstration of Rh platings in the Slovenian firm Zlatarna Celje d.d.

  11. Serial dilution microchip for cytotoxicity test

    Science.gov (United States)

    Bang, Hyunwoo; Lim, Sun Hee; Lee, Young Kyung; Chung, Seok; Chung, Chanil; Han, Dong-Chul; Chang, Jun Keun

    2004-08-01

    Today's pharmaceutical industry is facing challenges resulting from the vast increases in sample numbers produced by high-throughput screening (HTS). In addition, the bottlenecks created by increased demand for cytotoxicity testing (required to assess compound safety) are becoming a serious problem. We have developed a polymer PDMS (polydimethylsiloxane) based microfluidic device that can perform a cytotoxicity test in a rapid and reproducible manner. The concept that the device includes is well adjustable to automated robots in huge HTS systems, so we can think of it as a potential dilution and delivery module. Cytotoxicity testing is all about the dilution and dispensing of a drug sample. Previously, we made a PDMS based microfluidic device which automatically and precisely diluted drugs with a buffer solution with serially increasing concentrations. This time, the serially diluted drug solution was directly delivered to 96 well plates for cytotoxicity testing. Cytotoxic paclitaxel solution with 2% RPMI 1640 has been used while carrying out cancerous cell based cytotoxicity tests. We believe that this rapid and robust use of the PDMS microchip will overcome the growing problem in cytotoxicity testing for HTS.

  12. Creep-fatigue evaluation method for weld joint of Mod.9Cr-1Mo steel Part II: Plate bending test and proposal of a simplified evaluation method

    Energy Technology Data Exchange (ETDEWEB)

    Ando, Masanori, E-mail: ando.masanori@jaea.go.jp; Takaya, Shigeru, E-mail: takaya.shigeru@jaea.go.jp

    2016-12-15

    Highlights: • Creep-fatigue evaluation method for weld joint of Mod.9Cr-1Mo steel is proposed. • A simplified evaluation method is also proposed for the codification. • Both proposed evaluation method was validated by the plate bending test. • For codification, the local stress and strain behavior was analyzed. - Abstract: In the present study, to develop an evaluation procedure and design rules for Mod.9Cr-1Mo steel weld joints, a method for evaluating the creep-fatigue life of Mod.9Cr-1Mo steel weld joints was proposed based on finite element analysis (FEA) and a series of cyclic plate bending tests of longitudinal and horizontal seamed plates. The strain concentration and redistribution behaviors were evaluated and the failure cycles were estimated using FEA by considering the test conditions and metallurgical discontinuities in the weld joints. Inelastic FEA models consisting of the base metal, heat-affected zone and weld metal were employed to estimate the elastic follow-up behavior caused by the metallurgical discontinuities. The elastic follow-up factors determined by comparing the elastic and inelastic FEA results were determined to be less than 1.5. Based on the estimated elastic follow-up factors obtained via inelastic FEA, a simplified technique using elastic FEA was proposed for evaluating the creep-fatigue life in Mod.9Cr-1Mo steel weld joints. The creep-fatigue life obtained using the plate bending test was compared to those estimated from the results of inelastic FEA and by a simplified evaluation method.

  13. Investigation of Thermal Performance of Flat Plate and Evacuated Tubular Solar Collectors According to a New Dynamic Test Method

    DEFF Research Database (Denmark)

    Kong, Weiqiang; Wang, Zhifeng; Fan, Jianhua;

    2012-01-01

    obtain fluid thermal capacitance in data processing. Then theoretical analysis and experimental verification are carried out to investigate influencing factors of obtaining accurate and stable second order term. A flat plate and ETC solar collector are compared using both the new dynamic method......A new dynamic test method is introduced. This so called improved transfer function method features on two new collector parameters. One is time term which can indicate solar collector's inner heat transfer ability and the other is a second order term of collector mean fluid temperature which can...... and a standard method. The results show that the improved function method can accurately and robustly estimate these two kinds of solar collectors....

  14. Evaluation method for ductile crack propagation in pre-strained plates; Yohizumizai no ensei kiretsu denpa hyokaho

    Energy Technology Data Exchange (ETDEWEB)

    Ueda, Y.; Murakawa, H. [Osaka Univ., Osaka (Japan). Welding Research Inst.; Tanigawa, M. [Hitachi Zosen Corp., Osaka (Japan)

    1996-12-31

    In order to investigate an effect of the plastic deformation, which was generated on ship side outer platings subjected to collision load before crack initiation, on the crack propagation behavior, crack propagation experiments using pre-strained specimens and simulation analysis by means of FEM method were carried out, to discuss about the practical simulation analysis method. As a result of the crack propagation experiments using pre-strained center notched plate specimens, a phenomenon where the crack is apt to propagate due to the pre-strains was confirmed, and measured data of crack tip opening angles were obtained. A method was proposed, in which the critical crack tip opening angle values are corrected by considering the difference between the crack shapes obtained from the FEM analysis model and actually measured, and its effectiveness was confirmed. The finite element size effect was also examined. A method using an equivalent plastic strain as the crack propagation condition was shown to determine the relationship between the element size and the critical value of equivalent plastic strain. 5 refs., 21 figs., 4 tabs.

  15. A method for acoustic source location in plate-type structures

    Science.gov (United States)

    Mostafapour, Amir; Davoodi, Saman

    2017-09-01

    In this study an algorithm based on Shannon entropy, cross-time frequency spectrum (CTFS) and frequency varying velocities was proposed for structure health monitoring in two-layer plate. A linear array of two sensors is applied to capture the signals. By reducing the number of sensors we used a secondary pattern to get enough information for source locating. For this purpose a pattern for secondary points based on Shannon entropy and cost function was developed. Then to estimate the time delay of signals, cross-time frequency spectrum function was taken from captured signals. The time delay was calculated when CTFS function reached the maximum value. By taking short time Fourier transform of cross correlation function of captures signals and using dispersive curves, time delay and corresponding frequency dependent velocity are estimated. The experiments were carried out and the results showed high precision of presented algorithm.

  16. A compensating method of an imaging plate response to clinical proton beams

    CERN Document Server

    Kohno, R; Takada, Y; Terunuma, T; Sakae, T; Matsumoto, K

    2002-01-01

    For charged particle irradiations, the response of an imaging plate (IP) changes around the Bragg peak. Therefore, an appropriate compensation is necessary for the evaluation of dose distribution formed by charged particles such as protons. In this paper, the response of IPs to clinical proton beams is investigated. An experimentally-obtained depth-dose distribution (an ordinary Bragg curve) by a silicon semiconductor detector (SSD) is employed to evaluate the compensation factors as a function of proton penetrating depth, i.e. residual range. A typical dose distribution in a water phantom formed by an L-shaped bolus is measured by IPs and corrected by using the information of those compensation factors; the residual proton range is successfully calculated by the pencil beam algorithm at an arbitrary point. The results show a good agreement with the measurements by the SSD within the rms error of 3.0%.

  17. Component mode synthesis and large deflection vibration of complex structures. Volume 2: Single-mode large deflection vibrations of beams and plates using finite element method

    Science.gov (United States)

    Mei, Chuh

    1987-01-01

    A finite element method is presented for the large amplitude vibrations of complex structures that can be modelled with beam and rectangular plate elements subjected to harmonic excitation. Both inplane deformation and inertia are considered in the formulation. Derivation of the harmonic force and nonlinear stiffness matrices for a beam and a rectangular plate element are presented. Solution procedures and convergence characteristics of the finite element method are described. Nonlinear response to uniform and concentrated harmonic loadings and improved nonlinear free vibration results are presented for beams and rectangular plates of various boundary conditions.

  18. Conversion from film to image plates for transfer method neutron radiography of nuclear fuel

    Energy Technology Data Exchange (ETDEWEB)

    Craft, Aaron E.; Papaioannou, Glen C.; Chichester, David L.; Williams, Walter J.

    2017-02-01

    This paper summarizes efforts to characterize and qualify a computed radiography (CR) system for neutron radiography of irradiated nuclear fuel at Idaho National Laboratory (INL). INL has multiple programs that are actively developing, testing, and evaluating new nuclear fuels. Irradiated fuel experiments are subjected to a number of sequential post-irradiation examination techniques that provide insight into the overall behavior and performance of the fuel. One of the first and most important of these exams is neutron radiography, which provides more comprehensive information about the internal condition of irradiated nuclear fuel than any other non-destructive technique to date. Results from neutron radiography are often the driver for subsequent examinations of the PIE program. Features of interest that can be evaluated using neutron radiography include irradiation-induced swelling, isotopic and fuel-fragment redistribution, plate deformations, and fuel fracturing. The NRAD currently uses the foil-film transfer technique with film for imaging fuel. INL is pursuing multiple efforts to advance its neutron imaging capabilities for evaluating irradiated fuel and other applications, including conversion from film to CR image plates. Neutron CR is the current state-of-the-art for neutron imaging of highly-radioactive objects. Initial neutron radiographs of various types of nuclear fuel indicate that radiographs can be obtained of comparable image quality currently obtained using film. This paper provides neutron radiographs of representative irradiated fuel pins along with neutron radiographs of standards that informed the qualification of the neutron CR system for routine use. Additionally, this paper includes evaluations of some of the CR scanner parameters and their effects on image quality.

  19. Collaborative study of a microbiological screening method (three-plate) for the banned antimicrobial growth promotors tylosin, virginiamycin, spiramycin, zinc bacitracin and avoparcin in animal feed

    NARCIS (Netherlands)

    Pol-Hofstad, I.; Lankveld, van W.D.M.; Tomassen, M.J.H.; Jong, de J.; Egmond, van H.J.

    2008-01-01

    A microbiological screening method (three-plate) for the detection of the antimicrobial growth promoters tylosin, spiramycin, virginiamycin, zinc bacitracin, and avoparcin in animal feed has been developed and validated successfully. A collaborative study involving 18 laboratories receiving 172

  20. Collaborative study of a microbiological screening method (three-plate) for the banned antimicrobial growth promotors tylosin, virginiamycin, spiramycin, zinc bacitracin and avoparcin in animal feed

    NARCIS (Netherlands)

    Pol-Hofstad, I.; Lankveld, van W.D.M.; Tomassen, M.J.H.; Jong, de J.; Egmond, van H.J.

    2008-01-01

    A microbiological screening method (three-plate) for the detection of the antimicrobial growth promoters tylosin, spiramycin, virginiamycin, zinc bacitracin, and avoparcin in animal feed has been developed and validated successfully. A collaborative study involving 18 laboratories receiving 172 samp

  1. 一种实用的基于形态学和标志法的车牌字符切分方法%A Practical Method of Car License Plate Character Segmentation Based on Morphology and Labeling

    Institute of Scientific and Technical Information of China (English)

    王明祥; 莫玉龙

    2001-01-01

    In this paper, a kind of practical image segmentation algorithm for segment characters from car license plate is presented, based on morphology and labeling. First, by morphological operation, noise in the binary image of license plate can be greatly decreased. Then, by labeling, each connected pixel component is given a unique label. Finally, by the known data of license plate, each character is extracted correctly. The advantage of this method is that it can deal with plates with different sizes and connected characters plates, and inclined plates. The experiment results show that it is an effective way to extract characters from the license plate, and can be put into practical use.

  2. 一种实用的基于形态学和标志法的车牌字符切分方法%A Practical Method of Car License Plate Character Segmentation Based on Morphology and Labeling

    Institute of Scientific and Technical Information of China (English)

    王明祥; 莫玉龙

    2000-01-01

    In this paper, a kind of practical image segmentation algorithm for segment characters from car license plate is presented, based on morphology and labeling. First, by morphological operation, noise in the binary image of license plate can be greatly decreased. Then, by labeling, each connected pixel component is given a unique label. Finally, by the known data of license plate, each character is extracted correctly. The advantage of this method is that it can deal with plates with different sizes and connected characters plates, and inclined plates. The experiment results show that it is an effective way to extract characters from the license plate, and can be put into practical use.

  3. Multipotent Mesenchymal Stromal Stem Cell Expansion by Plating Whole Bone Marrow at a Low Cellular Density: A More Advantageous Method for Clinical Use

    Science.gov (United States)

    Mareschi, Katia; Rustichelli, Deborah; Calabrese, Roberto; Gunetti, Monica; Sanavio, Fiorella; Castiglia, Sara; Risso, Alessandra; Ferrero, Ivana; Tarella, Corrado; Fagioli, Franca

    2012-01-01

    Mesenchymal stem cells (MSCs) are a promising source for cell therapy due to their pluripotency and immunomodulant proprieties. As the identification of “optimal” conditions is important to identify a standard procedure for clinical use. Percoll, Ficoll and whole bone marrow directly plated were tested from the same sample as separation methods. The cells were seeded at the following densities: 100 000, 10 000, 1000, 100, 10 cells/cm2. After reaching confluence, the cells were detached, pooled and re-plated at 1000, 500, 100, and 10 cells/cm2. Statistical analyses were performed. Cumulative Population Doublings (PD) did not show significant differences for the separation methods and seeding densities but only for the plating density. Some small quantity samples plated in T25 flasks at plating densities of 10 and 100 cells/cm2 did not produce any expansion. However, directly plated whole bone marrow resulted in a more advantageous method in terms of CFU-F number, cellular growth and minimal manipulation. No differences were observed in terms of gross morphology, differentiation potential or immunophenotype. These data suggest that plating whole bone marrow at a low cellular density may represent a good procedure for MSC expansion for clinical use. PMID:23715383

  4. Multipotent Mesenchymal Stromal Stem Cell Expansion by Plating Whole Bone Marrow at a Low Cellular Density: A More Advantageous Method for Clinical Use

    Directory of Open Access Journals (Sweden)

    Katia Mareschi

    2012-01-01

    Full Text Available Mesenchymal stem cells (MSCs are a promising source for cell therapy due to their pluripotency and immunomodulant proprieties. As the identification of “optimal” conditions is important to identify a standard procedure for clinical use. Percoll, Ficoll and whole bone marrow directly plated were tested from the same sample as separation methods. The cells were seeded at the following densities: 100 000, 10 000, 1000, 100, 10 cells/cm2. After reaching confluence, the cells were detached, pooled and re-plated at 1000, 500, 100, and 10 cells/cm2. Statistical analyses were performed. Cumulative Population Doublings (PD did not show significant differences for the separation methods and seeding densities but only for the plating density. Some small quantity samples plated in T25 flasks at plating densities of 10 and 100 cells/cm2 did not produce any expansion. However, directly plated whole bone marrow resulted in a more advantageous method in terms of CFU-F number, cellular growth and minimal manipulation. No differences were observed in terms of gross morphology, differentiation potential or immunophenotype. These data suggest that plating whole bone marrow at a low cellular density may represent a good procedure for MSC expansion for clinical use.

  5. Estudo comparativo entre as técnicas de diluição em caldo e diluição em ágar, nos antibiogramas para Candida: a comparative study Broth dilution and agar dilution methods applied to Candida sensitivity tests

    Directory of Open Access Journals (Sweden)

    Sydney Hartz Alves

    1992-06-01

    Full Text Available Os autores compararam o desempenho das técnicas de diluição em caldo e diluição em ágar, mediante a determinação da CIM (concentração inibitória mínima e da CFM (concentração fungicida mínima de antifúngicos poliênicos e imidazólicos, frente a diversas espécies de Candida. A concordância entre as técnicas foi variável em função do antifúngico utilizado. Os melhores percentuais de concordância ocorreram quando se realizou o teste com poliênicos. Os autores discutem aspectos que envolvem a problemática dos testes de sensibilidade de leveduras a antifúngicosThe performance of broth dilution method and agar dilution method were compared by MIC (minimal inhibitory concentration and MFC (minimal fungicidal concentration from Candida strains to polyene and imizadole anti-fungal agents. The concordance between these methods was drug dependent. The best percent of concordance were showed when the polyenes were tested. The problems of sensitivity test for yeasts to antifungal drugs are discussed

  6. Development of new finite element by source method. 2nd Report. Plate bending element; Source wo mochiita atarashii yugen yoso no kaihatsu. 2. Itamage yoso

    Energy Technology Data Exchange (ETDEWEB)

    Neki, I.; Tada, T. [Ishikawajima-Harima Heavy Industries Co. Ltd., Tokyo (Japan)

    1996-12-31

    This paper reports a method to develop a new finite element by source (FES) for a two-dimensional plane problem and a three-dimensional solid problem as a method to analyze ship body structures. The paper describes development of a plate bending element by using a similar method, and the fundamental principle thereof. The present method can prepare a finite element of an arbitrary shape by simply providing a contact point only on a boundary. It can also derive good calculation accuracy with less number of contact points and elements. These facts are shown by examples of analyses on a square plate, a triangle plate and a semi-circular plate. Particularly, since a plate bending problem has a large order of differential calculus in a governing equation, this method being a semi-analytical method derives a result with very good accuracy even with less number of contact points. A hypothetical boundary method or a hypothetical electric charge method presents not a very high accuracy even if a large number of contact points are provided. This is because the method hypothesizes only a bending moment vertical to the boundary, but does not consider a source of the moment relative to the boundary. In contrast, the present method hypothesizes both of bending and twisting as the sources, hence its accuracy is better than with the above two methods. 5 refs., 11 figs., 7 tabs.

  7. Vibration and Buckling of Web Plate of the Plate Girder

    OpenAIRE

    高橋, 和雄; 呉, 明強; 中澤, 聡志; 筑紫, 宏之

    1998-01-01

    The vibration and buckling of the web of the plate girder are studied in this paper. The small deflection theory of the thin plate is used. The finite strip method is employed to solve vibration and buckling of the plate girder. Natural frequenies of buckling properties are shown for various plate girder bridges.

  8. A method to increase the nominal range resolution of a stack of parallel-plate ionization chambers

    Science.gov (United States)

    Rinaldi, I.; Brons, S.; Jäkel, O.; Voss, B.; Parodi, K.

    2014-09-01

    A detector prototype based on a stack of 61 parallel-plate ionisation chambers (PPIC) interleaved with absorber plates of polymethyl methacrylate (PMMA) was assembled for transmission imaging purposes in ion beam therapy. The thickness of the absorber sheets in the PPIC stack determines the nominal range resolution of the detector. In the current set-up, 3 mm PMMA slabs are used. The signal of the 61 active channels of the stack thereby provides a discrete approximation of the Bragg curve in the detector. In this work, a data processing method to increase the range resolution (MIRR) in a stack of ionization chambers is presented. In the MIRR the position of the maximum of the Bragg curve is deduced from the ratio of measured signals in adjacent PPIC channels. The method is developed based on Bragg curves obtained from Monte Carlo simulations and validated with experimental data of a wedge-shaped PMMA phantom acquired with the PPIC stack using carbon ion beams. The influence of the initial beam energy and of phantom inhomogeneities on the MIRR is quantitatively evaluated. Systematic errors as well as inaccuracies related to signal noise are discussed and quantified. It is shown that with the MIRR an increased range resolution of 0.7 mm PMMA equivalent or 0.8 mm water equivalent thickness is achieved for the considered experimental data.

  9. Bending and stretching of plates

    CERN Document Server

    Mansfield, E H; Hemp, W S

    1964-01-01

    The Bending and Stretching of Plates deals with elastic plate theory, particularly on small- and large-deflexion theory. Small-deflexion theory concerns derivation of basic equations, rectangular plates, plates of various shapes, plates whose boundaries are amenable to conformal transformation, plates with variable rigidity, and approximate methods. Large-deflexion theory includes general equations and some exact solutions, approximate methods in large-deflexion theory, asymptotic large-deflexion theories for very thin plates. Asymptotic theories covers membrane theory, tension field theory, a

  10. ANTI-MICROBIAL ACTIVITY OF THE CRUDE DRUGS AND THE POLYHERBAL FORMULATION (RVSPHF567 BY STANDARDIZED CUP AND PLATE METHOD

    Directory of Open Access Journals (Sweden)

    C.S. Kandasamy

    2011-10-01

    Full Text Available Antimicrobial study of crude drugs (Ajowan, Cardamom, Cumin, Mace, Clove, and Nutmeg and the Polyherbal formulation RVSPHF567 was assayed by standardized cup and plate method by using bacterial andfungal culture. The microorganisms used are Aspergillus niger (fungus, Streptococcus aureus (G+ve bacteria and Escherchia coli (G-ve bacteria. These microbes were cultured in a suitable nutritional media for their growth. The extractions of crude drugs were achieved by dissolving their powdered drugs in the suitable solvent. The solvents used for extracting crude drugs were alcohol and water, the solvent used for the preparation of the Polyherbal formulation RVSPHF567 was red tender coconut water. These extracted crude drugs and the Polyherbal formulation RVSPHF567 were then transferred to the pits on the solidified agar media, previously incubated with the different micro-organism separately. Then the plates were streaked with bacterial cultures and kept in an incubator at 37oC for 24hrs for growth of bacterial cultures, and plates streaked with fungal culture were incubated at 25°C for 24hrs. After the incubation period the growth of microbes and their zone of inhibition surrounding the extracts of the crude drugs and the Polyherbal formulation RVSPHF567 were observed and measured. All the crude drugs and the Polyherbal formulation RVSPHF567 were found to bespecifically effective against bacterial and fungal strain. Ajowan, Cardamom, Clove, Cumin, and Mace is highly active against Aspergillus niger. Nutmeg is highly active against Streptococcus, Polyherbal formulation RVSPHF567 is highly active against all the three organisms namely Aspergillus niger, Streptococcus aureus, Escherchia coli.

  11. [PHYSICAL AND MATHEMATICAL GROUNDS LANDFORMS BASIS PLATE DENTURES WHEN APPLYING THE COMPLEX METHOD OF PREVENTION OF PROSTHETIC STOMATITIS].

    Science.gov (United States)

    Zverkhanovsky, A

    2016-06-01

    Objective - to develop the form of the drug reservoir to hold the vegetable oils under the basis of the prosthesis. The research was conducted on the Bench PMMA samples. The comparison group consisted of smooth plate PMMA. Two study groups were PMMA plates with grooves on one side of a square with sides of 2 mm and depth of channel - 1 mm. The third group consisted of the experimental plate with diamond-shaped notches with the same parameters. The lowest value of the stress in the plate having a rhombic grid, they are 54% less than in the smooth plate and 37% less than in the plate with a square lattice (the best strength characteristics in a rhombic plate with grille). Equivalent move from the plate with a rhombic lattice is less than an order of magnitude than that of a smooth plate and by 5.8% more than at the plate with a square lattice, which indicates good performance design plasticity with rhombic grid. Basis with the rhombic lattice on the surface has the best record on the stress-strain state in comparison with other models considered (smooth plate with a square lattice plate).

  12. Fabrication of CNT Dispersion Fluid by Wet-Jet Milling Method for Coating on Bipolar Plate of Fuel Cell

    Directory of Open Access Journals (Sweden)

    Anas Almowarai

    2015-01-01

    Full Text Available Water based carbon nanotube (CNT dispersion was produced by wet-jet milling method. Commercial CNT was originally agglomerated at the particle size of less than 1 mm. The wet-jet milling process exfoliated CNTs from the agglomerates and dispersed them into water. Sedimentation of the CNTs in the dispersion fluid was not observed for more than a month. The produced CNT dispersion was characterized by the SEM and the viscometer. CNT/PTFE composite film was formed with the CNT dispersion in this study. The electrical conductivity of the composite film increased to 10 times when the CNT dispersion, which was produced by the wet-jet milling method, was used as a constituent of the film. Moreover, the composite film was applied to bipolar plate of fuel cell and increased the output power of the fuel cell to 1.3 times.

  13. Separation method of heavy-ion particle image from gamma-ray mixed images using an imaging plate

    CERN Document Server

    Yamadera, A; Ohuchi, H; Nakamura, T; Fukumura, A

    1999-01-01

    We have developed a separation method of alpha-ray and gamma-ray images using the imaging plate (IP). The IP from which the first image was read out by an image reader was annealed at 50 deg. C for 2 h in a drying oven and the second image was read out by the image reader. It was found out that an annealing ratio, k, which is defined as a ratio of the photo-stimulated luminescence (PSL) density at the first measurement to that at the second measurement, was different for alpha rays and gamma rays. By subtracting the second image multiplied by a factor of k from the first image, the alpha-ray image was separated from the alpha and gamma-ray mixed images. This method was applied to identify the images of helium, carbon and neon particles of high energies using the heavy-ion medical accelerator, HIMAC. (author)

  14. Fracture analysis of one-dimensional hexagonal quasicrystals: Researches of a finite dimension rectangular plate by boundary collocation method

    Energy Technology Data Exchange (ETDEWEB)

    Jiaxing, Cheng; Dongfa, Sheng [Southwest Forestry University, Yunnan (China)

    2017-05-15

    As an important supplement and development to crystallography, the applications about quasicrystal materials have played a core role in many fields, such as manufacturing and the space industry. Due to the sensitivity of quasicrystals to defects, the research on the fracture problem of quasicrystals has attracted a great deal of attention. We present a boundary collocation method to research fracture problems for a finite dimension rectangular one-dimensional hexagonal quasicrystal plate. Because mode I and mode II problems for one- dimensional hexagonal quasicrystals are like that for the classical elastic materials, only the anti-plane problem is discussed in this paper. The correctness of the present numerical method is verified through a comparison of the present results and the existing results. And then, the size effects on stress field, stress intensity factor and energy release rate are discussed in detail. The obtained results can provide valuable references for the fracture behavior of quasicrystals.

  15. Analysis of the discontinuous Petrov-Galerkin method with optimal test functions for the Reissner-Mindlin plate bending model

    KAUST Repository

    Calo, Victor M.

    2014-01-01

    We analyze the discontinuous Petrov-Galerkin (DPG) method with optimal test functions when applied to solve the Reissner-Mindlin model of plate bending. We prove that the hybrid variational formulation underlying the DPG method is well-posed (stable) with a thickness-dependent constant in a norm encompassing the L2-norms of the bending moment, the shear force, the transverse deflection and the rotation vector. We then construct a numerical solution scheme based on quadrilateral scalar and vector finite elements of degree p. We show that for affine meshes the discretization inherits the stability of the continuous formulation provided that the optimal test functions are approximated by polynomials of degree p+3. We prove a theoretical error estimate in terms of the mesh size h and polynomial degree p and demonstrate numerical convergence on affine as well as non-affine mesh sequences. © 2013 Elsevier Ltd. All rights reserved.

  16. Air-coupled method to investigate the lowest-order antisymmetric Lamb mode in stubbed and air-drilled phononic plates

    Directory of Open Access Journals (Sweden)

    Dongbo Zhang

    2016-08-01

    Full Text Available In this work, we applied a robust and fully air-coupled method to investigate the propagation of the lowest-order antisymmetric Lamb (A0 mode in both a stubbed and an air-drilled phononic-crystal (PC plate. By measuring simply the radiative acoustic waves of A0 mode close to the plate surface, we observed the band gaps for the stubbed PC plate caused by either the local resonance or the Bragg scattering, in frequency ranges in good agreement with theoretical predictions. We measured then the complete band gap of A0 mode for the air-drilled PC plate, in good agreement with the band structures. Finally, we compared the measurements made using the air-coupled method with those obtained by the laser ultrasonic technique.

  17. Air-coupled method to investigate the lowest-order antisymmetric Lamb mode in stubbed and air-drilled phononic plates

    Science.gov (United States)

    Zhang, Dongbo; Zhao, Jinfeng; Bonello, Bernard; Li, Libing; Wei, Jianxin; Pan, Yongdong; Zhong, Zheng

    2016-08-01

    In this work, we applied a robust and fully air-coupled method to investigate the propagation of the lowest-order antisymmetric Lamb (A0) mode in both a stubbed and an air-drilled phononic-crystal (PC) plate. By measuring simply the radiative acoustic waves of A0 mode close to the plate surface, we observed the band gaps for the stubbed PC plate caused by either the local resonance or the Bragg scattering, in frequency ranges in good agreement with theoretical predictions. We measured then the complete band gap of A0 mode for the air-drilled PC plate, in good agreement with the band structures. Finally, we compared the measurements made using the air-coupled method with those obtained by the laser ultrasonic technique.

  18. Application of laser ranging and VLBI data to a study of plate tectonic driving forces. [finite element method

    Science.gov (United States)

    Solomon, S. C.

    1980-01-01

    The measurability of changes in plate driving or resistive forces associated with plate boundary earthquakes by laser rangefinding or VLBI is considered with emphasis on those aspects of plate forces that can be characterized by such measurements. Topics covered include: (1) analytic solutions for two dimensional stress diffusion in a plate following earthquake faulting on a finite fault; (2) two dimensional finite-element solutions for the global state of stress at the Earth's surface for possible plate driving forces; and (3) finite-element solutions for three dimensional stress diffusion in a viscoelastic Earth following earthquake faulting.

  19. Effect of plating time on growth of nanocrystalline Ni–P from sulphate/glycine bath by electroless deposition method

    Indian Academy of Sciences (India)

    N Latha; V Raj; M Selvam

    2013-08-01

    Nanocrystalline nickel phosphorus (NC-Ni–P) deposits from sulphate/glycine bath using a simple electroless deposition process is demonstrated. In the present investigation, nanoporous alumina films are formed on the aluminium surface by anodization process followed by deposition of nickel onto the pores by electroless plating method. Anodic aluminium oxide surface was first sensitized and activated by using palladium chloride solution before immersing into the electroless nickel bath. Electroless nickel plating was carried out from the optimized bath by changing the deposition time from 20 to 1800 s at a constant temperature of 80 °C and a pH of 4.0. Surface morphology, elemental composition, structure and reflectance of the deposits have been analysed by using scanning electron microscopy, atomic force microscopy, energy dispersive X-ray analysis, X-ray diffractometry and UV-visible spectroscopic studies, respectively. Electroless nickel deposits formed at an early stage produces dense uniform nanocrystals containing higher percentage of atomic phosphorus with cubic Ni (111) structure. As the deposition time increased, nanocrystalline sharp peak became amorphous and dimension of the crystal size varied from 54 to 72 nm.

  20. Optimization of the polypyrrole-coating parameters for proton exchange membrane fuel cell bipolar plates using the Taguchi method

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yan; Northwood, Derek O. [Department of Mechanical, Automotive, and Materials Engineering, University of Windsor, 401 Sunset Avenue, Windsor, Ontario (Canada)

    2008-10-15

    In order to overcome the high price, weight and volume of non-porous graphite bipolar plates, metallic bipolar plates are being investigated as a substitute material. However, metallic materials can corrode under proton exchange membrane fuel cell (PEMFC) working conditions, leading to a degradation in the performance of the membrane. Previous work had shown that a polypyrrole coating on SS316L can significantly increase the corrosion resistance of the base material. In this study, a Taguchi design of experiment method was used to optimize the process parameters for the polypyrrole coating so as to produce the maximum corrosion resistance. Potentiodynamic and potentiostatic tests were used to determine the corrosion resistance of the polypyrrole-coated SS316L. Scanning electron microscopy (SEM) with energy dispersive X-ray (EDX) was used to characterize the coating thickness and coating appearance. Inductively coupled plasma optical emission spectroscopy (ICP-OES) was used to determine the metal ion concentration in the solution after corrosion. The interfacial contact resistance of SS316L with carbon paper was measured both before and after coating with polypyrrole. (author)

  1. Buckling analysis of laminated plates using the extended Kantorovich method and a system of first-order differential equations

    Energy Technology Data Exchange (ETDEWEB)

    Singhatanadgid, Pairod; Jommalai, Panupan [Chulalongkorn University, Bangkok (Thailand)

    2016-05-15

    The extended Kantorovich method using multi-term displacement functions is applied to the buckling problem of laminated plates with various boundary conditions. The out-of-plane displacement of the buckled plate is written as a series of products of functions of parameter x and functions of parameter y. With known functions in parameter x or parameter y, a set of governing equations and a set of boundary conditions are obtained after applying the variational principle to the total potential energy of the system. The higher order differential equations are then transformed into a set of first-order differential equations and solved for the buckling load and mode. Since the governing equations are first-order differential equations, solutions can be obtained analytically with the out-of-plane displacement written in the form of an exponential function. The solutions from the proposed technique are verified with solutions from the literature and FEM solutions. The bucking loads correspond very well to other available solutions in most of the comparisons. The buckling modes also compare very well with the finite element solutions. The proposed solution technique transforms higher-order differential equations to first-order differential equations, and they are analytically solved for out-of-plane displacement in the form of an exponential function. Therefore, the proposed solution technique yields a solution which can be considered as an analytical solution.

  2. Adaptive Lagrange finite element methods for high precision vibrations and piezoelectric acoustic wave compu- tations in SMT structures and plates with nano interfaces

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    This paper discusses the validity of (adaptive) Lagrange generalized plain finite element method(FEM) and plate element method for accurate analysis of acoustic waves in multi-layered piezoelectric structures with tiny interfaces between metal electrodes and surface mounted piezoelectric substrates. We have come to conclusion that the quantitative relationships between the acoustic and electric fields in a piezoelectric structure can be accurately determined through the proposed finite element methods. The higher-order Lagrange FEM proposed for dynamic piezoelectric computation is proved to be very accurate (prescribed relative error 0.02%-0.04%) and a great improvement in convergence accuracy over the higher order Mindlin plate element method for piezoelectric structural analysis due to the assumptions and corrections in the plate theories. The converged Lagrange finite element methods are compared with the plate element methods and the computed results are in good agreement with available exact and experimental data. The adaptive Lagrange finite element methods and a new FEA computer program developed for macro- and micro-scale analyses are reviewed, and recently extended with great potential to high-precision nano-scale analysis in this paper and the similarities between piezoelectric and seismic wave propagations in layered structures and plates are stressed.

  3. An Investigation on Monolithic U-Mo Plate Type Fuel by a Pressure-Sintering Method

    Energy Technology Data Exchange (ETDEWEB)

    Kim, C. K.; Oh, J. M.; Jang, S. J. [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Choi, G. H.; Chun, B. S. [Chungnam National University, Daejeon (Korea, Republic of)

    2009-05-15

    Previously the average particle diameter of U-Mo powder used for developing U-Mo dispersion fuel was about 50 {mu}m. U-Mo/Al dispersion fuels were shown that an extensive interaction between the UMo particle and the Al matrix occurred in high power- density of dispersion fuel. Because the interaction product has a low thermal conductivity and density, which have harmful effects for fuel performance, several attempts to avoid the above problems have been made such as (1) the decrease of the contacting area between the fuel and Al matrix, (2) the increase of the alloy stability of the interaction phase through the addition of an additional alloying element, such as Si, Ti and Zr, into the Al matrix. In KAERI U-Mo powder with very large particle size of more than 500 {mu}m could be produced by rotating disk centrifugal atomization process through adjusting the operating parameters in 2006. A consideration was taken for an application of a large particle to plate type fuel with a layer array. When the particles of spherical shape arrayed in a closed packing way the equivalent U-density of fuel meat would approach to more than 8 g-U/cc. The interface temperature between the U-Mo particle and the Al matrix is expected to be low because aluminum with good thermal conductivity is connected from the interface to the cooling water without any thermal diffusion interruption. The temperature at the center of the large U-Mo particle is calculated to be not too high. When the heat flux and the particle diameter are supposed to be 560 W/cm{sup 2} and 700 {mu}m, the temperature difference was about 36 .deg. C. In addition, the U-Mo particles are surrounded with an aluminum matrix so that a little of the constraint force will act on the fuel particles from the aluminum matrix. A problem like debonding between U-Mo foil and Al cladding in monolithic U-Mo fuel under development can be avoided. Some experiments related to the fabrication of large particle array fuel were carried out

  4. Development of Multiwell-Plate Methods Using Pure Cultures of Methanogens To Identify New Inhibitors for Suppressing Ruminant Methane Emissions.

    Science.gov (United States)

    Weimar, M R; Cheung, J; Dey, D; McSweeney, C; Morrison, M; Kobayashi, Y; Whitman, W B; Carbone, V; Schofield, L R; Ronimus, R S; Cook, G M

    2017-08-01

    Hydrogenotrophic methanogens typically require strictly anaerobic culturing conditions in glass tubes with overpressures of H2 and CO2 that are both time-consuming and costly. To increase the throughput for screening chemical compound libraries, 96-well microtiter plate methods for the growth of a marine (environmental) methanogen Methanococcus maripaludis strain S2 and the rumen methanogen Methanobrevibacter species AbM4 were developed. A number of key parameters (inoculum size, reducing agents for medium preparation, assay duration, inhibitor solvents, and culture volume) were optimized to achieve robust and reproducible growth in a high-throughput microtiter plate format. The method was validated using published methanogen inhibitors and statistically assessed for sensitivity and reproducibility. The Sigma-Aldrich LOPAC library containing 1,280 pharmacologically active compounds and an in-house natural product library (120 compounds) were screened against M. maripaludis as a proof of utility. This screen identified a number of bioactive compounds, and MIC values were confirmed for some of them against M. maripaludis and M. AbM4. The developed method provides a significant increase in throughput for screening compound libraries and can now be used to screen larger compound libraries to discover novel methanogen-specific inhibitors for the mitigation of ruminant methane emissions.IMPORTANCE Methane emissions from ruminants are a significant contributor to global greenhouse gas emissions, and new technologies are required to control emissions in the agriculture technology (agritech) sector. The discovery of small-molecule inhibitors of methanogens using high-throughput phenotypic (growth) screening against compound libraries (synthetic and natural products) is an attractive avenue. However, phenotypic inhibitor screening is currently hindered by our inability to grow methanogens in a high-throughput format. We have developed, optimized, and validated a high

  5. A Method of License Plate Location based on Mathematical Morphology%基于数学形态学的车牌定位方法

    Institute of Scientific and Technical Information of China (English)

    陈佳; 刘立

    2014-01-01

    In order to locate the position of the plate accurately, in this paper, a precise license plate locating algorithm is proposed based on mathematical morphology. Firstly, after gray level transformation of the color plate image, Sobel operator is used to detect the edge of the car image, Secondly, the methods of erosion and closing operation in mathematical morphology are adopted to process the binary image, and several candidate license plate areas are obtained. Then, removing false license plate area by the line scanning method to achieve coarse location of license plate. Finally, Hough transform is applied to locate the plate precisely. The experimental results show that the method can achieve the purpose of precise license plate location.%为了准确定位车牌的位置,提出了基于数学形态学的车牌定位方法。该方法首先将彩色图像灰度化,并利用Sobel算子进行图像边缘提取,然后运用数学形态学的腐蚀和闭运算对二值图像进行处理,可以得到几个车牌候选区,接着再利用行扫描去除伪车牌区域,实现车牌的粗定位。最后,利用Hough变换精确定位车牌的位置。实验表明,这一方法能够准确地实现车牌的定位。

  6. 复方硼砂溶液(稀)微生物限度检查法验证%Validation of microbial limit test method of compound borax solution( diluted )

    Institute of Scientific and Technical Information of China (English)

    刘全芳; 郑绍忠; 张婷

    2011-01-01

    目的 建立复方硼砂溶液(稀)的微生物限度检查法.方法 依据2010年版二部附录XI J微生物限度检查法常规法进行验证试验.结果 验证试验中试验组的加菌回收率均大于70%,控制菌检查可检出阳性菌,阴性菌不能检出.结论 可以采用常规法进行复方硼砂溶液(稀)的微生物限度检查.%Aim To establish a method for the microbial limit test of compound borax solution( diluted ). Methods A validation of microbial limit test method was conducted in accordance with routine method stated in the appendix of "Chinese Pharmacopoeia" 2010Edition 2. Results The recoveries of test bacteria by routine method were more than 70%. The test bacteria were detected in the control bacteria test and were not detected in the negative control bacteria test. Conclusion Conventional method can be applied to Compound Borax Solution( diluted )in microbial limit test.

  7. Adaptive Lagrange finite element methods for high precision vibrations and piezoelectric acoustic wave computations in SMT structures and plates with nano interfaces

    Institute of Scientific and Technical Information of China (English)

    张武; 洪涛

    2002-01-01

    This paper discusses the validity of (adaptive) Lagrange generalized plain finite element method (FEM) and plate element method for accurate analysis of acoustic waves in multi-layered piezoelectric structures with tiny interfaces between metal electrodes and surface mounted piezoelectric substrates. We have come to conclusion that the quantitative relationships between the acoustic and electric fields in a piezoelectric structure can be accurately determined through the proposed finite element methods. The higher-order Lagrange FEM proposed for dynamic piezoelectric computation is proved to be very accurate (prescribed relative error 0.02% - 0.04% ) and a great improvement in convergence accuracy over the higher order Mindlin plate element method for piezoelectric structural analysis due to the assumptions and corrections in the plate theories.The converged lagrange finite element methods are compared with the plate element methods and the computedresults are in good agreement with available exact and experimental data. The adaptive Lagrange finite elementmethods and a new FEA computer program developed for macro- and micro-scale analyses are reviewed, and recently extended with great potential to high-precision nano-scale analysis in this paper and the similarities between piezoelectric and seismic wave propagations in layered structures and plates are stressed.

  8. Influence of volume expansion on NaC1 reabsorption in the diluting segments of the nephron: a study using clearance methods.

    Science.gov (United States)

    Danovitch, G M; Bricker, N S

    1976-09-01

    Whether volume expansion influences NaC1 reabsorption by the diluting segment of the nephron remains a matter of controversy. In the present studies this question has been examined in normal unanesthetized dogs, undergoing maximal water diuresis. Free water clearance (CH2O/GFR) has been used as the index of NaC1 reabsorption in the diluting segment. Three expressions have been employed for "distal delivery" of NaC1: a) V/GFR, designated as the "volume term"; b) (CNa/GFR + CH2O/GFR), the "sodium term;" and c) (CC1/GFR + CH2O/GFR), the "chloride term". The validity of these terms is discussed. Three techniques were used to increase distal delivery: 1) the administration of acetazolamide to dogs in which extracellular fluid (ECF) volume was not expanded (grop 1); 2) "moderate" volume expansion (group 2); and 3) "marked" volume expansion (group 3). CH2O/GFR increased progressively with rising values for "distal delivery" regardless of which term was used to calculate the latter. With all three delivery terms, differences in distal NaC1 reabsorption emerged between the two volume-expanded groups, though only with the "chloride" term did substantial differences also emerge between the nonexpanded group 1 dogs and both volume-expanded groups. In group 1, values for CH2O/GFR increased in close to a linear fashion up to distal delivery values equal to 24% of the volume of glomerular filtrate. However, at high rates of distal delivery the rate of rise of CH2O/GFR was less in group 2 than in group 1 and the depression of values was even greater in group 3. Within the limits of the techniques used, the data suggest that volume expansion inhibits fractional NaC1 reabsorption in the diluting segment of the nephron in a dose-related fashion. The "chloride" term was found to be superior to the "volume" and "sodium" terms in revealing these changes.

  9. Estimation of dispersion curves by combining Effective Elastic Constants and SAFE Method: A case study in a plate under stress

    Science.gov (United States)

    Quiroga, J. E.; Mujica, L.; Villamizar, R.; Ruiz, M.; Camacho, J.

    2017-05-01

    This paper presents an approach to calculate dispersion curves for homogeneous and isotropic plates subject to stress, via Semi-Analytical Finite Element and the Effective Elastic Constants, since stresses in the waveguide modify the phase and group velocities of the lamb waves. In the proposed methodology an isotropic specimen subjected to anisotropic loading is emulated by proposing an equivalent stress-free anisotropic specimen. This approximation facilitates determining the dispersion curves by using the well-studied numerical solution for the stress-free cases. The lamb wave in anisotropic materials can be studied by means of the Effective Elastic Constants, which reduces the complexity of the numerical implementation. Finally, numerical data available in literature were used to validate the proposed methodology, where it could be demonstrated its effectiveness as approximated method.

  10. Optical thickness measurement of mask blank glass plate by the excess fraction method using a wavelength-tuning interferometer

    Science.gov (United States)

    Kim, Yangjin; Hibino, Kenichi; Sugita, Naohiko; Mitsuishi, Mamoru

    2013-10-01

    The absolute optical thickness of a 140-mm2 mask blank glass plate 3.1 mm thickness was measured by three-surface interferometry using a wavelength-tuning Fizeau interferometer. The interference order was determined by the excess fraction method. The wavelength of a tunable laser diode was scanned linearly from 632 to 642 nm, and a CCD detector recorded 2000 interference images. Two kinds of optical thicknesses measured by discrete Fourier analysis and phase-shifting were synthesized to obtain the optical thickness with respect to the ordinary refractive index. The optical thickness defined by the group refractive index at the 637 nm central wavelength was measured by wavelength scanning. The optical thickness deviation defined by the ordinary refractive index was measured using tunable phase-shifting. The systematic errors caused by nonlinearity in the wavelength tuning were corrected through correlation analysis between the theoretical and observed interference fringes.

  11. Optimization of the Adhesion Strength of Arc Ion Plating TiAlN Films by the Taguchi Method

    Directory of Open Access Journals (Sweden)

    Tong-Yul Cho

    2009-06-01

    Full Text Available A three-level six-factor (arc power, substrate temperature, pre-treatment bias voltage, working pressure, deposition bias voltage and pretreatment time orthogonal experimental array (L18 to optimize the adhesion strength of arc ion plating (AIP TiAlN films was designed using the Taguchi method. An optimized film process, namely substrate temperature 220 °C, arc power 60 A, negative bias voltage -800 V, nitrogen pressure 10-2 Torr, pretreated voltage -450 V and pretreated time 15 minutes was obtained by the Taguchi program for the purpose of obtaining a larger critical load. The critical load of the optimized TiAlN film (53 N was increased by 43% compared to the film with the highest critical load before optimization. The improvement in the adhesion strength of the films was attributed to the enhancement of hardness and the competitive growth of the (111, (200 and (220 orientations in the film.

  12. Thermodynamic equilibrium solubility measurements in simulated fluids by 96-well plate method in early drug discovery.

    Science.gov (United States)

    Bharate, Sonali S; Vishwakarma, Ram A

    2015-04-01

    An early prediction of solubility in physiological media (PBS, SGF and SIF) is useful to predict qualitatively bioavailability and absorption of lead candidates. Despite of the availability of multiple solubility estimation methods, none of the reported method involves simplified fixed protocol for diverse set of compounds. Therefore, a simple and medium-throughput solubility estimation protocol is highly desirable during lead optimization stage. The present work introduces a rapid method for assessment of thermodynamic equilibrium solubility of compounds in aqueous media using 96-well microplate. The developed protocol is straightforward to set up and takes advantage of the sensitivity of UV spectroscopy. The compound, in stock solution in methanol, is introduced in microgram quantities into microplate wells followed by drying at an ambient temperature. Microplates were shaken upon addition of test media and the supernatant was analyzed by UV method. A plot of absorbance versus concentration of a sample provides saturation point, which is thermodynamic equilibrium solubility of a sample. The established protocol was validated using a large panel of commercially available drugs and with conventional miniaturized shake flask method (r(2)>0.84). Additionally, the statistically significant QSPR models were established using experimental solubility values of 52 compounds.

  13. Boundary integral equation methods in eigenvalue problems of elastodynamics and thin plates

    CERN Document Server

    Kitahara, M

    1985-01-01

    The boundary integral equation (BIE) method has been used more and more in the last 20 years for solving various engineering problems. It has important advantages over other techniques for numerical treatment of a wide class of boundary value problems and is now regarded as an indispensable tool for potential problems, electromagnetism problems, heat transfer, fluid flow, elastostatics, stress concentration and fracture problems, geomechanical problems, and steady-state and transient electrodynamics.In this book, the author gives a complete, thorough and detailed survey of the method. It pro

  14. A development of the method of the control signal formation for the hot plate mill automation systems to improve the flatness of the finish plate

    Directory of Open Access Journals (Sweden)

    Voronin Stanislav S.

    2016-01-01

    Full Text Available This article describes how to control of the hot plate mill automation system to improve the quality metrics if the final strip. Based on the data of the modern hot rolling mills the classification of the cage equipment was designed. Depending on the degree of influence on the magnitude of reduction, the equipment was divided into categories. The functioning of every system including the main and the vertical cages was described. The conditions of electrical and hydraulic mechanisms was marked. The developed algorithm allows to improve defects based on the finite number of the thickness measurements given by special non-contact sensors. The example of regulators signals calculating was shown. The result of the algorithm operating was illustrated.

  15. One dimension spring supported ball on top of a sinusoidal vibrating plate: A forced oscillation simulation using molecular dynamics method

    CERN Document Server

    Viridi, Sparisoma; Hidayat, Wahyu; Singarimbun, Alamta; Balkis, Sitti

    2011-01-01

    A ball supported by a spring is set on top of a plate which is sinusoidal vibrated. The motion is limited to one dimension motion. It is assumed that the spring is an ideal one with zero mass. The vibrating plate is considered much heavier than the ball, so that the ball motion has no influence on the plate motion. Plate vibration frequency is varied around the frequency of ball-spring system. Resonance phenomenon is reported, which needs a phase match condition to occur.

  16. Plate-like structure damage location identification based on Lamb wave baseline-free probability imaging method

    Directory of Open Access Journals (Sweden)

    Dongsheng Li

    2017-01-01

    Full Text Available Damage-scattering signal extraction using conventional ultrasonic guided wave–based damage detection techniques requires the measurement of baseline data under pristine condition. This study proposes a baseline-free ultrasonic guided wave damage localization and imaging method based on Lamb wave baseline-free probability imaging method. Although traditional Lamb wave probability imaging can monitor damage location in plate-like structures, the absolute time of arrival and magnitude of the signal are affected by several factors and are therefore difficult to obtain. This study also proposes a probability-based hyperbola diagnostic imaging method that is based on different times of arrival and has no magnitude information. A distributed active sensor network conforming to a pulse-echo configuration and time window functions is developed to separate damage-scattering signals from structural response signals. Continuous wavelet transform is used to calculate the time of flight of damage signal waves. The numerical simulation and experiments validate the effectiveness of the proposed method in identifying damage.

  17. 一种快速的车牌自动定位方法%A Fast Automatic Location Method of Vehicle License Plate

    Institute of Scientific and Technical Information of China (English)

    李万相; 田莹

    2015-01-01

    车牌定位是车牌识别系统中最重要的步骤,针对车牌区域的特点,提出一种简单快速的车牌粗定位方法。首先对拍摄的包含车牌的彩色车身图像进行灰度化,并采用自动阈值方法进行二值化,对于不同颜色车身图像都能得到理想的二值图像,然后对二值图像利用梯度进行边缘检测,再根据车牌区域水平方向具有黑白灰度跳变较为频繁的特征,采用行扫描图像的灰度跳变频率来定位车牌区域。在拍摄的车牌图像上进行定位实验表明,方法具有简单实用,速度快的特点。%Automatic license plate location is the most important step in license plate recognition system. According to the characteristics of the li-cense plate area, proposes a simple and fast method for the coarse location of the license plate. First of all, the color image of the license plate is gray, and the automatic threshold method is used to carry on binarization. The method can be used for different color images. Then gradient operator is used to detect the edge of the binary image. And then the gray-hopping frequency is used to locate the license plate area. Experiments on license plate images show that the proposed method is simple, practical, and fast.

  18. Order Parameters of the Dilute A Models

    CERN Document Server

    Warnaar, S O; Seaton, K A; Nienhuis, B

    1993-01-01

    The free energy and local height probabilities of the dilute A models with broken $\\Integer_2$ symmetry are calculated analytically using inversion and corner transfer matrix methods. These models possess four critical branches. The first two branches provide new realisations of the unitary minimal series and the other two branches give a direct product of this series with an Ising model. We identify the integrable perturbations which move the dilute A models away from the critical limit. Generalised order parameters are defined and their critical exponents extracted. The associated conformal weights are found to occur on the diagonal of the relevant Kac table. In an appropriate regime the dilute A$_3$ model lies in the universality class of the Ising model in a magnetic field. In this case we obtain the magnetic exponent $\\delta=15$ directly, without the use of scaling relations.

  19. Quantitative Laser Biospeckle Method for the Evaluation of the Activity of Trypanosoma cruzi Using VDRL Plates and Digital Analysis

    Science.gov (United States)

    Grassi, Hilda Cristina; García, Lisbette C.; Lobo-Sulbarán, María Lorena; Velásquez, Ana; Andrades-Grassi, Francisco A.; Cabrera, Humberto; Andrades-Grassi, Jesús E.; Andrades, Efrén D. J.

    2016-01-01

    In this paper we report a quantitative laser Biospeckle method using VDRL plates to monitor the activity of Trypanosoma cruzi and the calibration conditions including three image processing algorithms and three programs (ImageJ and two programs designed in this work). Benznidazole was used as a test drug. Variable volume (constant density) and variable density (constant volume) were used for the quantitative evaluation of parasite activity in calibrated wells of the VDRL plate. The desiccation process within the well was monitored as a function of volume and of the activity of the Biospeckle pattern of the parasites as well as the quantitative effect of the surface parasite quantity (proportion of the object’s plane). A statistical analysis was performed with ANOVA, Tukey post hoc and Descriptive Statistics using R and R Commander. Conditions of volume (100μl) and parasite density (2-4x104 parasites/well, in exponential growth phase), assay time (up to 204min), frame number (11 frames), algorithm and program (RCommander/SAGA) for image processing were selected to test the effect of variable concentrations of benznidazole (0.0195 to 20μg/mL / 0.075 to 76.8μM) at various times (1, 61, 128 and 204min) on the activity of the Biospeckle pattern. The flat wells of the VDRL plate were found to be suitable for the quantitative calibration of the activity of Trypanosoma cruzi using the appropriate algorithm and program. Under these conditions, benznidazole produces at 1min an instantaneous effect on the activity of the Biospeckle pattern of T. cruzi, which remains with a similar profile up to 1 hour. A second effect which is dependent on concentrations above 1.25μg/mL and is statistically different from the effect at lower concentrations causes a decrease in the activity of the Biospeckle pattern. This effect is better detected after 1 hour of drug action. This behavior may be explained by an instantaneous effect on a membrane protein of Trypanosoma cruzi that could

  20. Quantitative Laser Biospeckle Method for the Evaluation of the Activity of Trypanosoma cruzi Using VDRL Plates and Digital Analysis.

    Science.gov (United States)

    Grassi, Hilda Cristina; García, Lisbette C; Lobo-Sulbarán, María Lorena; Velásquez, Ana; Andrades-Grassi, Francisco A; Cabrera, Humberto; Andrades-Grassi, Jesús E; Andrades, Efrén D J

    2016-12-01

    In this paper we report a quantitative laser Biospeckle method using VDRL plates to monitor the activity of Trypanosoma cruzi and the calibration conditions including three image processing algorithms and three programs (ImageJ and two programs designed in this work). Benznidazole was used as a test drug. Variable volume (constant density) and variable density (constant volume) were used for the quantitative evaluation of parasite activity in calibrated wells of the VDRL plate. The desiccation process within the well was monitored as a function of volume and of the activity of the Biospeckle pattern of the parasites as well as the quantitative effect of the surface parasite quantity (proportion of the object's plane). A statistical analysis was performed with ANOVA, Tukey post hoc and Descriptive Statistics using R and R Commander. Conditions of volume (100μl) and parasite density (2-4x104 parasites/well, in exponential growth phase), assay time (up to 204min), frame number (11 frames), algorithm and program (RCommander/SAGA) for image processing were selected to test the effect of variable concentrations of benznidazole (0.0195 to 20μg/mL / 0.075 to 76.8μM) at various times (1, 61, 128 and 204min) on the activity of the Biospeckle pattern. The flat wells of the VDRL plate were found to be suitable for the quantitative calibration of the activity of Trypanosoma cruzi using the appropriate algorithm and program. Under these conditions, benznidazole produces at 1min an instantaneous effect on the activity of the Biospeckle pattern of T. cruzi, which remains with a similar profile up to 1 hour. A second effect which is dependent on concentrations above 1.25μg/mL and is statistically different from the effect at lower concentrations causes a decrease in the activity of the Biospeckle pattern. This effect is better detected after 1 hour of drug action. This behavior may be explained by an instantaneous effect on a membrane protein of Trypanosoma cruzi that could

  1. Improvement of Surface Roughness Quality for Stainless Steel 420 Plate Using Magnetic Abrasive Finishing Method

    Directory of Open Access Journals (Sweden)

    Yahya M. Hamad

    2010-01-01

    Full Text Available An experimental study was carried out to improve the surface roughness quality of the stainless steel 420 using magnetic abrasive finishing method (MAF. Four independent operation parameters were studied (working gap, coil current, feed rate, and table stroke, and their effects on the MAF process were introduced. A rotating coil electromagnet was designed and implemented to use with plane surfaces. The magnetic abrasive powder used was formed from 33%Fe and 67% Quartz of (250µm mesh size. The lubricant type SAE 20W was used as a binder for the powder contents. Taguchi method was used for designing the experiments and the optimal values of the selected parameters were found. An empirical equation representing the relation between surface roughness with operation parameters have been achieved.

  2. Direct numerical simulation methods of hypersonic flat-plate boundary layer in thermally perfect gas

    Science.gov (United States)

    Jia, WenLi; Cao, Wei

    2014-01-01

    High-temperature effects alter the physical and transport properties of air such as vibrational excitation in a thermally perfect gas, and this factor should be considered in order to compute the flow field correctly. Herein, for the thermally perfect gas, a simple method of direct numerical simulation on flat-plat boundary layer is put forward, using the equivalent specific heat ratio instead of constant specific heat ratio in the N-S equations and flux splitting form of a calorically perfect gas. The results calculated by the new method are consistent with that by solving the N-S equations of a thermally perfect gas directly. The mean flow has the similarity, and consistent to the corresponding Blasius solution, which confirms that satisfactory results can be obtained basing on the Blasius solution as the mean flow directly in stability analysis. The amplitude growth curve of small disturbance is introduced at the inlet by using direct numerical simulation, which is consistent with that obtained by linear stability theory. It verified that the equation established and the simulation method is correct.

  3. Optimization Of Curved Plated Structures With The Finite Strip And Finite Element Methods

    Directory of Open Access Journals (Sweden)

    Balogh Bence

    2015-12-01

    Full Text Available The aim of this study is to compare two available numerical tools for solving of partial differential equations for the optimal design of structures. In the past years numerous methods were developed for topology optimization, from these we have adopted the optimality criteria (OC approach. The main idea is that we state the optimal conditions, that the minimizer has to fulfil at the end of an iterative proves. This method however is not a general one, only advantageous in the case of separable problems, but comes with fast speed, easy programming, and a relative insensitivity of computational time to the number of variables. In the paper we suggest a new method for the elimination of a numerical error, the so called ‘checkerboard pattern’. In the presented examples we applied one loading case and an elastic material behaviour. The cost function is the net weight of the structure and upper bound of the compliance is set as the optimality constraint.

  4. Stacking sequence and shape optimization of laminated composite plates via a level-set method

    Science.gov (United States)

    Allaire, G.; Delgado, G.

    2016-12-01

    We consider the optimal design of composite laminates by allowing a variable stacking sequence and in-plane shape of each ply. In order to optimize both variables we rely on a decomposition technique which aggregates the constraints into one unique constraint margin function. Thanks to this approach, an exactly equivalent bi-level optimization problem is established. This problem is made up of an inner level represented by the combinatorial optimization of the stacking sequence and an outer level represented by the topology and geometry optimization of each ply. We propose for the stacking sequence optimization an outer approximation method which iteratively solves a set of mixed integer linear problems associated to the evaluation of the constraint margin function. For the topology optimization of each ply, we lean on the level set method for the description of the interfaces and the Hadamard method for boundary variations by means of the computation of the shape gradient. Numerical experiments are performed on an aeronautic test case where the weight is minimized subject to different mechanical constraints, namely compliance, reserve factor and buckling load.

  5. A comparison of standard cultural methods for the detection of foodborne Salmonella species including three new chromogenic plating media.

    Science.gov (United States)

    Schönenbrücher, Vanessa; Mallinson, Edward T; Bülte, Michael

    2008-03-31

    In this study the draft of the horizontal method for the detection of Salmonella species from human food and animal feed (ISO 6579:2002) was compared to the European gold standard (DIN EN 12824:1998), including the three new chromogenic plating media AES Salmonella Agar Plate (ASAP), Oxoid Salmonella Chromogen Media (OSCM) and Miller-Mallinson agar (MM). First the growth and appearance of 36 bacterial type strains (Salmonella and other 21 species) on ASAP, OSCM and MM were compared to those on the three traditional agars Brilliant Green Agar according to Edel and Kampelmacher (BGA), Xylose Lysine Deoxycholate Agar (XLD) and Xylose Lysine Tergitol 4 Agar (XLT4). Only on MM agar, did all of 36 tested type strains produce typical colonies, especially strains of S. Senftenberg, Salmonella arizonae, S. Dublin and S. Derby. Artificial inoculation experiments using raw pork ground meat (n=92) were subsequently conducted. A shortened incubation time of 24 h in RVS broth yielded a Salmonella species recovery of 100% from spiked meat samples. Finally, 286 naturally contaminated raw porcine and bovine minced meat samples and raw poultry meat samples were investigated. Forty-three strains from a total of 39 Salmonella-positive samples were found. S. Typhimurium (n=21), with DT 104 L, DT 012 and RDNC being the most prevalent subtypes isolated. D-tartrate-positive S. Paratyphi B (n=2) and S. Saint-Paul (n=3) were also recovered. They were cultured from poultry meat and were multi-resistant against antibiotics including nalidixic acid. Rappaport Vassiliadis broth with soypeptone (RVS) yielded the highest recovery of Salmonella spp. (97,4%) compared to Tetrathionate broth with Novobiocin according to Muller and Kauffman (MKTTn, 94,9%) and Selenite Cystine broth (SC, 38,5%). However, no significant difference was obtained by comparing the ISO 6579:2002 draft to the gold standard.

  6. Comparison of plate reader-based methods with fluorescence microscopy for measurements of intracellular calcium levels for the assessment of in vitro neurotoxicity.

    Science.gov (United States)

    Meijer, Marieke; Hendriks, Hester S; Heusinkveld, Harm J; Langeveld, Wendy T; Westerink, Remco H S

    2014-12-01

    The intracellular calcium concentration ([Ca(2+)]i) is an important readout for in vitro neurotoxicity since calcium is critically involved in many essential neurobiological processes, including neurotransmission, neurodegeneration and neurodevelopment. [Ca(2+)]i is often measured with considerable throughput at the level of cell populations with plate reader-based assays or with lower throughput at the level of individual cells with fluorescence microscopy. However, these methodologies yield different quantitative and qualitative results. In recent years, we demonstrated that the resolution and sensitivity of fluorescence microscopy is superior compared to plate reader-based assays. However, it is currently unclear if the use of plate reader-based assays results in more 'false negatives' or 'false positives' in neurotoxicity screening studies. In the present study, we therefore compared a plate reader-based assay with fluorescence microscopy using a small test set of environmental pollutants consisting of dieldrin, lindane, polychlorinated biphenyl 53 (PCB53) and tetrabromobisphenol-A (TBBPA). Using single-cell fluorescence microscopy, we demonstrate that all test chemicals reduce the depolarization-evoked increase in [Ca(2+)]i, whereas lindane, PCB53 and TBBPA also increase basal [Ca(2+)]i, though via different mechanisms. Importantly, none of these effects were confirmed with the plate reader-based assay. We therefore conclude that standard plate reader-based methods are not sufficiently sensitive and reliable to measure the highly dynamic and transient changes in [Ca(2+)]i that occur during chemical exposure. Copyright © 2014 Elsevier Inc. All rights reserved.

  7. Large Scale Screening of Southern African Plant Extracts for the Green Synthesis of Gold Nanoparticles Using Microtitre-Plate Method.

    Science.gov (United States)

    Elbagory, Abdulrahman M; Cupido, Christopher N; Meyer, Mervin; Hussein, Ahmed A

    2016-11-08

    The preparation of gold nanoparticles (AuNPs) involves a variety of chemical and physical methods. These methods use toxic and environmentally harmful chemicals. Consequently, the synthesis of AuNPs using green chemistry has been under investigation to develop eco-friendly nanoparticles. One approach to achieve this is the use of plant-derived phytochemicals that are capable of reducing gold ions to produce AuNPs. The aim of this study was to implement a facile microtitre-plate method to screen a large number of aqueous plant extracts to determine the optimum concentration (OC) for the bio-synthesis of the AuNPs. Several AuNPs of different sizes and shapes were successfully synthesized and characterized from 17 South African plants. The characterization was done using Ultra Violet-Visible Spectroscopy, Dynamic Light Scattering, High Resolution Transmission Electron Microscopy and Energy-Dispersive X-ray Spectroscopy. We also studied the effects of temperature on the synthesis of the AuNPs and showed that changes in temperatures affect the size and dispersity of the generated AuNPs. We also evaluated the stability of the synthesized AuNPs and showed that some of them are stable in biological buffer solutions.

  8. Large Scale Screening of Southern African Plant Extracts for the Green Synthesis of Gold Nanoparticles Using Microtitre-Plate Method

    Directory of Open Access Journals (Sweden)

    Abdulrahman M. Elbagory

    2016-11-01

    Full Text Available The preparation of gold nanoparticles (AuNPs involves a variety of chemical and physical methods. These methods use toxic and environmentally harmful chemicals. Consequently, the synthesis of AuNPs using green chemistry has been under investigation to develop eco-friendly nanoparticles. One approach to achieve this is the use of plant-derived phytochemicals that are capable of reducing gold ions to produce AuNPs. The aim of this study was to implement a facile microtitre-plate method to screen a large number of aqueous plant extracts to determine the optimum concentration (OC for the bio-synthesis of the AuNPs. Several AuNPs of different sizes and shapes were successfully synthesized and characterized from 17 South African plants. The characterization was done using Ultra Violet-Visible Spectroscopy, Dynamic Light Scattering, High Resolution Transmission Electron Microscopy and Energy-Dispersive X-ray Spectroscopy. We also studied the effects of temperature on the synthesis of the AuNPs and showed that changes in temperatures affect the size and dispersity of the generated AuNPs. We also evaluated the stability of the synthesized AuNPs and showed that some of them are stable in biological buffer solutions.

  9. 有限稀释克隆法培养分离人牙周膜干细胞实验研究%Experimental study of human periodontal stem cells cloning isolated and cultured by limited dilution method

    Institute of Scientific and Technical Information of China (English)

    封艳; 牛巧丽; 尹宏斌; 钟良军; 赵今

    2014-01-01

    Objective To obtain human periodontal ligament stem cell (hPDLSCs)cloning strain by limited dilution method for a preliminary research on its biological characteristics.Methods The limiting dilution method was adopted to separate gradually and screening hPDLSCs cloning from human periodontal liga-ment cells;the osteogenic capability in vitro,morphology and colony formation of the isolated hPDLSCs were observed;STRO-1,CD146 and other signs of protein expression were detected.Results The hP-DLSCs cloning obtained by limiting dilution similar were characteristic of the morphology of adult stem cells;Cell cycle analysis showed a slow cyclicality;STRO-1,CD146 were positively expressed by immu-nocytochemical staining;the cells induced by mineralization can express a variety of markers of bone pro-teins.Conclusion The purification of limited dilution can obtain hPDLSCs with the same features of adult stem cells in terms of cell cycle,phenotypic and osteogenic differentiation capacity.%目的:探讨有限稀释克隆法培养分离人牙周膜干细胞株的实验方法,并对其生物学特性进行初步研究。方法采用有限稀释克隆法对人牙周膜细胞逐步分离筛选,观察分离出的人牙周膜干细胞形态及克隆形成情况,并对其细胞周期、STRO-1、CD146等标志蛋白的表达进行检测,检测其体外诱导成骨的能力。结果通过有限稀释法获得人牙周膜干细胞克隆具有成体干细胞的形态特征;细胞周期分析呈慢周期性;免疫细胞化学染色证实 STRO-1、CD146及 Vimentin 均为阳性染色,矿化诱导证实该细胞可以表达多种骨蛋白标记物。结论采用有限稀释克隆法分离纯化可以获得成体干细胞所具有的细胞周期、表型及骨向分化能力等特点的牙周膜干细胞株。

  10. Non-Reflecting Regions for Finite Difference Methods in Modeling of Elastic Wave Propagation in Plates

    Science.gov (United States)

    Kishoni, Doron; Taasan, Shlomo

    1994-01-01

    Solution of the wave equation using techniques such as finite difference or finite element methods can model elastic wave propagation in solids. This requires mapping the physical geometry into a computational domain whose size is governed by the size of the physical domain of interest and by the required resolution. This computational domain, in turn, dictates the computer memory requirements as well as the calculation time. Quite often, the physical region of interest is only a part of the whole physical body, and does not necessarily include all the physical boundaries. Reduction of the calculation domain requires positioning an artificial boundary or region where a physical boundary does not exist. It is important however that such a boundary, or region, will not affect the internal domain, i.e., it should not cause reflections that propagate back into the material. This paper concentrates on the issue of constructing such a boundary region.

  11. A comparison of plate assay methods for detecting extracellular cellulase and xylanase activity.

    Science.gov (United States)

    Meddeb-Mouelhi, Fatma; Moisan, Jessica Kelly; Beauregard, Marc

    2014-11-01

    Identification of microorganisms for the production of carbohydrolytic enzymes is extremely important given the increased demand for these enzymes in many industries. To this end, dye-polysaccharide interactions which provide a visual indication of polymer hydrolysis (clear zones or halos) have been used for decades. For the detection of extracellular cellulase or xylanase activity many laboratories use Gram's iodine as the chromogenic dye, as it is a more rapid initial screening method compared to the use of other dyes. Here, we compared Gram's iodine and Congo red as indicators of polysaccharide hydrolysis. We attempted to detect cellulase activity using carboxymethylcellulose, and xylanase activity using birchwood xylan, in fourteen uncharacterized bacteria isolated from wood chips. Our results indicate that Gram's iodine may lead to identification of false positives in a typical screening protocol and that Congo red allows for avoidance of such pitfall. Congo red allowed detection of cellulase activity from live microbial colonies but not Gram's iodine. To confirm this, detection of enzymatic activity was also assessed using cell-free enzyme preparations. Congo red was found to be reliable in detecting cellulase activity with isolated enzymes preparations. Under the same conditions, neither of these dyes detected xylanase activity, despite independent evidence of xylanase activity for one of the preparations. We detected xylanase activity for this particular enzyme preparation using a coloured derivative of xylan (Remazol Brillant Blue R-xylan adduct) that respond to xylan hydrolysis. Our results suggest that methods that rely on interactions between a dye (Congo red or Gram's iodine) and a polymeric substrate (carboxymethylcellulose or birchwood xylan) for indirect detection of hydrolysis may require the use of relevant controls and independent confirmation of enzymatic activities.

  12. Phene Plate (PhP) biochemical fingerprinting. A screening method for epidemiological typing of enterococcal isolates.

    Science.gov (United States)

    Saeedi, B; Tärnberg, M; Gill, H; Hällgren, A; Jonasson, J; Nilsson, L E; Isaksson, B; Kühn, I; Hanberger, H

    2005-09-01

    Pulsed-field gel electrophoresis (PFGE) is currently considered the gold standard for genotyping of enterococci. However, PFGE is both expensive and time-consuming. The purpose of this study was to investigate whether the PhP system can be used as a reliable clinical screening method for detection of genetically related isolates of enterococci. If so, it should be possible to minimize the number of isolates subjected to PFGE typing, which would save time and money. Ninety-nine clinical enterococcal isolates were analysed by PhP (similarity levels 0.90-0.975) and PFGE (similarity levels PhP also belong to the same cluster according to PFGE, i.e. p(A(PFGE)=B(PFGE) * A(PhP)=B(PhP)), and the probability that a pair of isolates of different types according to PhP also belong to different clusters according to PFGE, i.e. p(A(PFGE) not equalB(PFGE) * A(PhP) not equalB(PhP)), was relatively high for E. faecalis (0.86 and 0.96, respectively), but was lower for E. faecium (0.51 and 0.77, respectively). The concordance which shows the probability that PhP and PFGE agree on match or mismatch was 86%-93% for E. faecalis and 54%-66% for E. faecium, which indicates that the PhP method may be useful for epidemiological typing of E. faecalis in the current settings but not for E. faecium.

  13. Casimir force between metal plate and dielectric plate

    Institute of Scientific and Technical Information of China (English)

    刘中柱; 邵成刚; 罗俊

    1999-01-01

    The Casimir effect between metal plate and dielectric plate is discussed with 1+1-dimensional potential model without using cut-off method. Calculation shows that the Casimir force between metal plate and dielectric plate is determined not only by the potential V0, the dielectric thickness and the distance α between the metal plate and dielectric plate, but also by the dimension of the vessel. When α is far less than the dimension of the vessel, the Casimir force Fc∝α(-1); conversely Fc∝α-2. This result is significant for Casimir force experiment.

  14. Research on location methods of license plate recognition%车辆牌照识别中车牌定位的研究

    Institute of Scientific and Technical Information of China (English)

    张剑

    2011-01-01

    License plate location is the first step of license plate recognition, also a very important one. This paper briefly introduces the characteristics of vehicle license and several common location methods. After license plate image preprocessing,it extracts the edge of the image with differential operator, and makes up for shortcomings of Sobel operator by morphology method. On the basis of pixel gray accumulated values in row, completes a license plate image in license plate recognition.%车牌定位是车牌识别系统的第一步,也是非常重要的一步,对车辆牌照的特征及几种常用的定位方法进行简要介绍,对车牌图像进行图像预处理之后,用微分算子对图像进行边缘提取,并且针对Sobel算子的缺点用形态学出来进行弥补.根据图像行、列像素点灰度值累加和对车牌图像进行定位,最后给出定位出的车牌图像.

  15. Calculations of Lamb wave band gaps and dispersions for piezoelectric phononic plates using mindlin's theory-based plane wave expansion method.

    Science.gov (United States)

    Hsu, Jin-Chen; Wu, Tsung-Tsong

    2008-02-01

    Based on Mindlin's piezoelectric plate theory and the plane wave expansion method, a formulation is proposed to study the frequency band gaps and dispersion relations of the lower-order Lamb waves in two-dimensional piezoelectric phononic plates. The method is applied to analyze the phononic plates composed of solid-solid and airsolid constituents with square and triangular lattices, respectively. Factors that influence the opening and width of the complete Lamb wave gaps are identified and discussed. For solid/solid phononic plates, it is suggested that the filling material be chosen with larger mass density, proper stiffness, and weak anisotropic factor embedded in a soft matrix in order to obtain wider complete band gaps of the lower-order Lamb waves. By comparing to the calculated results without considering the piezoelectricity, the influences of piezoelectric effect on Lamb waves are analyzed as well. On the other hand, for air/solid phononic plates, a background material itself with proper anisotropy and a high filling fraction of air may favor the opening of the complete Lamb wave gaps.

  16. Evaluation of the spiral plating method for the enumeration of microorganisms throughout the manufacturing and ripening of a raw goat's milk cheese.

    Science.gov (United States)

    Alonso-Calleja, Carlos; Carballo, Javier; Capita, Rosa; Bernardo, Ana; García-López, María Luisa

    2002-02-01

    A statistical comparison of the spiral plate count (SPLPC) and the standard plate count (SPC) methods for enumeration of microorganisms in raw goat's milk cheese throughout its manufacturing and ripening was carried out. Enumeration of mesophiles, lactic acid bacteria (presumptive lactococci, presumptive leuconostocs, and presumptive lactobacilli), Micrococcaceae, Enterobacteriaceae, and molds and yeasts was carried out for milk, curd, and 2-, 5-, 10-, 17-, and 27-day-old cheeses. Average counts for the SPLPC and SPC methods differed by less than half of a log cycle for all microbial groups studied (range of difference, -0.1386 [mesophiles] to +0.4397 [presumptive lactobacilli]). The results of the SPLPC method compared favorably with the results of the SPC procedure for mesophiles, presumptive lactococci, presumptive leuconostocs, Enterobacteriaceae, and molds and yeasts (the variance between replicate platings was close to 0.005, and correlation coefficients were >0.9). Correlation coefficients were lower for Micrococcaceae (r = 0.824) and presumptive lactobacilli (r = 0.670). Analysis of variance showed that the plating method was a significant factor (P microorganisms in goat cheese throughout its manufacturingand ripening processes. However, the suitability of the SPLPC method depends mainly on the microbial group studied.

  17. A study of narrow gap laser welding for thick plates using the multi-layer and multi-pass method

    Science.gov (United States)

    Li, Ruoyang; Wang, Tianjiao; Wang, Chunming; Yan, Fei; Shao, Xinyu; Hu, Xiyuan; Li, Jianmin

    2014-12-01

    This paper details a new method that combines laser autogenous welding, laser wire filling welding and hybrid laser-GMAW welding to weld 30 mm thick plate using a multi-layer, multi-pass process. A “Y” shaped groove was used to create the joint. Research was also performed to optimize the groove size and the processing parameters. Laser autogenous welding is first used to create the backing weld. The lower, narrowest part of the groove is then welded using laser wire filling welding. Finally, the upper part of the groove is welded using laser-GMAW hybrid welding. Additionally, the wire feeding and droplet transfer behaviors are observed by high speed photography. The two main conclusions from this work are: the wire is often biased towards the side walls, resulting in a lack of fusion at the joint and the creation of other defects for larger groove sizes. Additionally, this results in the droplet transfer behavior becoming unstable, leading to a poor weld appearance for smaller groove sizes.

  18. Detection and analysis of SERS effect of nano gold by self-assembly chemical plating composite method

    Science.gov (United States)

    Wang, Chunyan; Xu, Yi; Zhao, Huazhou; Gang, Chen; Lai, Chunhong; Liao, Xin; Wang, Rong

    2015-10-01

    Surface-enhanced Raman spectroscopy (SERS) as a powerful analytical tool has gained extensive attention. Despite of many efforts have been devoted to design SERS substrates, it still remains a grand challenge for creating a general substrate with high SERS active by a simple, controllable and low-cost way. Herein, we attempt to address this issue by fabricating SERS-active nano gold film based on self-assembly chemical plating composite method. The influence of gold colloid particle size on gold seed distribution density and the influence of the particle size of nano gold films on the SERS activity were investigated in detail. 10-5 M Rhodamine 6G (R6G) was taken as Raman probe molecules and homemade Raman detection microsystem was used as detector. According to the results of SERS detection, the SERS substrate enhancement factors (SSEF) were calculated, and the nano gold film with average particle size of about 55 nm showed the maximum SSEF of 0.93 × 105, which indicated such nano gold films showed excellent SERS activity. Moreover, these nano gold films are all low-cost and easy to prepared. This study provided theoretical and experimental basis for the design and preparation of general SERS substrate.

  19. An Optimized High Throughput Clean-Up Method Using Mixed-Mode SPE Plate for the Analysis of Free Arachidonic Acid in Plasma by LC-MS/MS

    OpenAIRE

    Wan Wang; Suzi Qin; Linsen Li; Xiaohua Chen; Qunjie Wang; Junfu Wei

    2015-01-01

    A high throughput sample preparation method was developed utilizing mixed-mode solid phase extraction (SPE) in 96-well plate format for the determination of free arachidonic acid in plasma by LC-MS/MS. Plasma was mixed with 3% aqueous ammonia and loaded into each well of 96-well plate. After washing with water and methanol sequentially, 3% of formic acid in acetonitrile was used to elute arachidonic acid. The collected fraction was injected onto a reversed phase column at 30°C with mobile pha...

  20. Effectiveness of antibiotic combination therapy as evaluated by the Break-point Checkerboard Plate method for multidrug-resistant Pseudomonas aeruginosa in clinical use.

    Science.gov (United States)

    Nakamura, Itaru; Yamaguchi, Tetsuo; Tsukimori, Ayaka; Sato, Akihiro; Fukushima, Shinji; Mizuno, Yasutaka; Matsumoto, Tetsuya

    2014-04-01

    Multidrug-resistant Pseudomonas aeruginosa (MDRP) strains are defined as having resistance to the following 3 groups of antibiotics: carbapenems, aminoglycosides, and fluoroquinolones. Antibiotic combinations have demonstrated increased activity in vitro compared with a single agent. As an in vitro method of determining the combination activity of antibiotics, the Break-point Checkerboard Plate (BC-plate) can be used routinely in clinical microbiology laboratories. We evaluated the effectiveness of the BC-plate for MDRP infections in clinical settings. We retrospectively selected cases of MDRP infection treated with combination therapy of antibiotics in Tokyo Medical University Hospital (1015 beds), Tokyo, Japan, from November 2010 to October 2012. A total of 28 MDRP strains were clinically isolated from 28 patients during the study period. This study design is a case series of MDRP infection. Six infections among the 28 patients were treated based on the results of the BC-plate assay, and the 6 strains tested positive for MBL. One patient had pneumonia, 3 had urinary tract infections, 1 had vertebral osteomyelitis, and 1 had nasal abscess. The combination of aztreonam with amikacin demonstrated the most frequently recognized in vitro effect (5 patients). Next, aztreonam with ciprofloxacin and piperacillin with amikacin revealed equivalent in vitro effects (3 patients, respectively). The clinical cure rate was 83.3% (5/6 patients). Antibiotic combination therapy based on the results of the BC-plate assay might indicate the effective therapy against MDRP infection in clinical settings.

  1. Estimation of Optimum Dilution in the GMAW Process Using Integrated ANN-GA

    Directory of Open Access Journals (Sweden)

    P. Sreeraj

    2013-01-01

    Full Text Available To improve the corrosion resistant properties of carbon steel, usually cladding process is used. It is a process of depositing a thick layer of corrosion resistant material over carbon steel plate. Most of the engineering applications require high strength and corrosion resistant materials for long-term reliability and performance. By cladding these properties can be achieved with minimum cost. The main problem faced on cladding is the selection of optimum combinations of process parameters for achieving quality clad and hence good clad bead geometry. This paper highlights an experimental study to optimize various input process parameters (welding current, welding speed, gun angle, and contact tip to work distance and pinch to get optimum dilution in stainless steel cladding of low carbon structural steel plates using gas metal arc welding (GMAW. Experiments were conducted based on central composite rotatable design with full replication technique, and mathematical models were developed using multiple regression method. The developed models have been checked for adequacy and significance. In this study, artificial neural network (ANN and genetic algorithm (GA techniques were integrated and labeled as integrated ANN-GA to estimate optimal process parameters in GMAW to get optimum dilution.

  2. Create Your Plate

    Medline Plus

    Full Text Available ... blood glucose levels and lose weight. With this method, you fill your plate with more non-starchy ... but changes the portion sizes so you are getting larger portions of non-starchy vegetables and a ...

  3. Create Your Plate

    Medline Plus

    Full Text Available ... blood glucose levels and lose weight. With this method, you fill your plate with more non-starchy ... 4/Box) Taking the guesswork out of portion control has never been easier. It can be a ...

  4. Create Your Plate

    Medline Plus

    Full Text Available ... blood glucose levels and lose weight. With this method, you fill your plate with more non-starchy ... you have an easy portion control solution that works. Last Reviewed: October 8, 2015 Last Edited: September ...

  5. Distribution of the hallucinogens N,N-dimethyltryptamine and 5-methoxy-N,N-dimethyltryptamine in rat brain following intraperitoneal injection: application of a new solid-phase extraction LC-APcI-MS-MS-isotope dilution method.

    Science.gov (United States)

    Barker, S A; Littlefield-Chabaud, M A; David, C

    2001-02-10

    A method for the solid-phase extraction (SPE) and liquid chromatographic-atmospheric pressure chemical ionization-mass spectrometric-mass spectrometric-isotope dilution (LC-APcI-MS-MS-ID) analysis of the indole hallucinogens N,N-dimethyltryptamine (DMT) and 5-methoxy DMT (or O-methyl bufotenin, OMB) from rat brain tissue is reported. Rats were administered DMT or OMB by the intraperitoneal route at a dose of 5 mg/kg and sacrificed 15 min post treatment. Brains were dissected into discrete areas and analyzed by the methods described as a demonstration of the procedure's applicability. The synthesis and use of two new deuterated internal standards for these purposes are also reported.

  6. 3M Petrifilm Staph Express Count plate method for the enumeration of Staphylococcus aureus in selected types of meat, seafood, and poultry: collaborative study.

    Science.gov (United States)

    McMahon, Wendy A; Aleo, Victoria A; Schultz, Ann M; Horter, Barbara L; Lindberg, Kathryn G

    2003-01-01

    The 3M Petrifilm Staph Express Count plate method was compared with AOAC Official Method 975.55 for the enumeration of Staphylococcus aureus in selected foods. Four foods--cooked, diced chicken; cured ham; smoked salmon; and pepperoni--were analyzed for S. aureus by 12 collaborating laboratories. For each food tested, the collaborators received 8 blind test samples consisting of a control sample, a low inoculation level, a medium inoculation level, and a medium inoculation level with background flora, each in duplicate. The mean log10 counts for the methods were comparable for all 4 foods. The repeatability and reproducibility variances of the 24 h Petrifilm Staph Express Count plate method were similar to those of the 72 h standard method.

  7. 3M Petrifilm Staph Express Count plate method for the enumeration of Staphylococcus aureus in selected types of processed and prepared foods: collaborative study.

    Science.gov (United States)

    Silbernagel, Karen M; Jechorek, Robert P; Carver, Charles N; Horter, Barbara L; Lindberg, Kathryn G

    2003-01-01

    The 3M Petrifilm Staph Express Count plate method was compared with AOAC Official Method 975.55 for the enumeration of Staphylococcus aureus in selected foods. Five foods--frozen lasagna, custard, frozen mixed vegetables, frozen hashbrowns, and frozen batter-coated mushrooms--were analyzed for S. aureus by 13 collaborating laboratories. For each food tested, the collaborators received 8 blind test samples consisting of a control sample, a low inoculation level, a medium inoculation level, and a medium inoculation level with background flora, each in duplicate. The mean log10 counts for the methods were comparable for all 5 foods. The repeatability and reproducibility variances of the 24 h Petrifilm Staph Express Count plate method were similar to those of the 72 h standard method.

  8. Effect of aspect ratio on large amplitude free vibrations of simply supported and clamped rectangular Mindlin plates using coupled displacement field method

    Energy Technology Data Exchange (ETDEWEB)

    Bhaskar, K. Krishna; Saheb, K. Meera [University College of Engineering, Kakinada (India)

    2017-05-15

    We propose a novel method, known as Coupled displacement field (CDF) method, an alternative to study large amplitude free vibration behavior of moderately thick rectangular plates. An admissible trial function was assumed for one of the variables, say, the total rotations (in both X, Y directions). The function for lateral displacement field is derived in terms of the total rotations with the help of coupling equations, where the two independent variables become dependent on one another. This method makes use of the energy formulation, where it contains only half the number of undetermined coefficients when compared with conventional Rayleigh-Ritz method. The vibration problem is simplified significantly due to the reduction in number of undetermined coefficients. The frequency -amplitude relationship for the moderately thick rectangular plates with various aspect ratios for all edges simply supported and clamped boundary conditions was obtained. Closed form expressions for linear and nonlinear fundamental frequency parameters were derived.

  9. Application of microbiological method direct epifluorescence filter techique/aerobic plate count agar in the identification of irradiated herbs and spices

    OpenAIRE

    Maria Concetta Campagna; Maria Teresa Di Schiavi; Marina Foti; Maria Cristina Mosconi; Giuseppina Mattiolo; Roberta Cavallina

    2014-01-01

    Irradiation is a preservation technology used to improve the safety and hygienic quality of food. Aim of this study was to assess the applicability and validity of the microbiological screening method direct epifluorescence filter technique (DEFT)/aerobic plate count (APC) (EN 13783:2001) for the identification of irradiated herbs and spices. Tests on non-irradiated and irradiated samples of dried herbs and spices were performed. The method was based on the comparison of APC and count obtaine...

  10. Combined Plate Microbial Assay (CPMA): a 6-plate-method for simultaneous first and second level screening of antibacterial residues in meat.

    Science.gov (United States)

    Ferrini, A M; Mannoni, V; Aureli, P

    2006-01-01

    This paper proposes an improved high throughput microbial method for the simultaneous performance of first and second level screening for antibacterial residues in meat. It is based on growth inhibition of B. subtilis on agar medium pH 6, 7.2 and 8, of B. cereus on agar medium pH 5.9, of M. luteus on agar medium pH 8 and of E. coli on agar medium pH 7.2 (research or first level screening) and on the use of confirmatory solutions (Pase, Paba, MgSO4) for the identification or second level screening. In kidney control samples, dialysis membranes were interposed between samples and the agar surface to both prevent the action of lysozyme and reduce false positive results. The proposed method detects beta-lactams, sulfonamides, tetracyclines, aminoglycosides, macrolides and quinolones at MRL concentrations and reliably indicates the inhibitor family. Results are obtained in 18-24 h.

  11. Research and Application of Positioning Method of Electroplating Plating Part%电镀镀件定位方法研究与应用

    Institute of Scientific and Technical Information of China (English)

    宋晓群; 尹勇; 李卉

    2013-01-01

    The plating parts often fall into the water during electroplating in manual electroplating production line.It can cause scrap for a long time. On the basis of the application of RFID technology, we proposed a location method. Each plating only corresponds to a label, then we calculate labels and reference tag distance that can quickly locate the plated position. The application of this method reduces plating factory's losses and improves the work efficiency of electroplating enterprises.%在手工电镀生产线电镀的过程中,镀件经常掉入水中,时间过长容易造成镀件报废。文章在应用RFID技术的基础上,提出一个区域定位方法,每个镀件唯一对应一个标签,计算标签与参考标签的距离,能够迅速定位镀件位置。该定位方法的应用减少了电镀厂的损失,提高了电镀企业的工作效率。

  12. Comparison of the compact dry TC and 3M petrifilm ACP dry sheet media methods with the spiral plate method for the examination of randomly selected foods for obtaining aerobic colony counts.

    Science.gov (United States)

    Ellis, P; Meldrum, R

    2002-02-01

    Two hundred thirty-six randomly selected food and milk samples were examined to obtain aerobic colony counts by two dry sheet media methods and a standard Public Health Laboratory Service spiral plate method. Results for 40 samples were outside the limits of detection for one or more of the tested methods and were not considered. (The limits of detection for the spiral plate method were 200 to 1 x 10(8) CFU/ml for the spiral plate method and 100 to 3 x 10(6) CFU/ml for the dry sheet media methods.) The remaining 196 sets of results were analyzed further. When the results from the three methods were compared, correlation coefficients were all >0.80 and slopes and intercepts were close to 1.0 and 0.0, respectively. Mean log values and standard deviations were very similar for all three methods. The results were evaluated according to published UK guidelines for ready-to-eat foods sampled at the point of sale, which include a quality acceptability assessment that is based on aerobic colony counts. Eighty-six percent of the comparable results gave the same verdict with regard to acceptability according to the aerobic colony count guidelines. Both dry sheet media methods were comparable to the spiral plate method and can be recommended for the examination of food.

  13. Development of a high throughput 96-well plate sample preparation method for the determination of trileptal (oxcarbazepine) and its metabolites in human plasma.

    Science.gov (United States)

    Souppart, C; Decherf, M; Humbert, H; Maurer, G

    2001-10-05

    A high throughput preparation method for the determination of trileptal (oxcarbazepine, OXC) and its mono (MHD) and dihydroxy (DHD) metabolites in human plasma, using 96-well plate technology, has been developed and validated according to international regulatory requirements. Preparation of plasma samples (50 microl) containing the compounds to be analysed involved solid-phase extraction (SPE) on Empore C18 96-well SPE plates. Eluates from the plate were injected onto a reversed-phase column (Hypersil C18,3 microm) with UV detection at 210 nm. Detector response was linear over the ranges 0.2-10, 0.1-200 and 0.1-20 micromol/l, for OXC, MHD and DHD, respectively, with relative standard deviations from 1 to 10% and mean accuracies within 4% of the nominal values (number of standard curves=3 in duplicate). The limits of quantitation were 0.2, 0.1 and 0.1 micromol/l, respectively. The overall mean accuracies ranged from 96 to 106% and precision was in the range 4 to 11%. Cross validation indicated no significant difference between plasma concentrations obtained using the 96-well method and the previous method using a traditional SPE method with a 50 mg C18 cartridge. About a threefold increase in sample throughput and a twofold decrease of plasma volume required for the assays, were the main advantages obtained from the previous method. The method was applied for the determination of 3000 plasma samples from clinical studies.

  14. COMPARISON BETWEEN TWO URINE DILUTION TESTS: THEIR ADVANTAGES AND DISADVANTAGES

    Directory of Open Access Journals (Sweden)

    Musso CG

    2015-05-01

    Full Text Available The main physiological test currently used for evaluating renal dilution capability is the hypotonic infusion test (HIT, which also evaluates proximal and thick ascending limb of Henle´s loops (TALH function. There is another urine dilution test: oral water load test, and it is simpler than HIT. However, it has not been documented yet if oral water load test performs an adequate evaluation of proximal tubule and TAHL activity, as HIT does. Thus, we decided to evaluate if there was any significant difference between both tests by evaluating: maximum urinary dilution capability, proximal sodium clearance, and TAHL sodium reabsorption. Materials and Method: Both urine dilution evaluating tests were prospectively performed to forty healthy volunteers with the aim of measuring the following physiological parameters by them: maximum urine hypotonicity, free water clearance, proximal tubule sodium clearance, and TALH sodium reabsorption. Results: All volunteers were able to maximally dilute their urine during HIT, while only 4 volunteers (10% were not able to do it during the oral water load tests. No significant difference was documented in the three studied parameters between both tests, in those patients who were able to maximally dilute their urine (n: 36 (p= NS. In conclusion this study has documented that HIT and oral water load test showed to be adequate studies for evaluating urine dilution capability, proximal and TAHL function. However, while HIT was more effective in obtaining the maximal dilution status, the oral water load test showed to be a simpler study.

  15. Tubularised Incised Plate Urethroplasty is an Applicable Method for the Treatment of the Hypospadiac Type of Urethral Duplication

    Directory of Open Access Journals (Sweden)

    Ömer Yılmaz

    2011-09-01

    Full Text Available Urethral duplication is a rare congenital anomaly usually seen in males. We present a case of urethral duplication treated by a tubularised incised plate urethroplasty (TIPU technique. A 5-year-old male boy was admitted to the clinic with the complaints of thin calibrated urinating and diurnal enuresis. We diagnosed distal penile hypospadias. During the operation, another urethral opening was found proximal to the previously seen hypospadiac meatus, localised on the coronary sulcus. We performed the TIPU procedure without excising the duplicated urethra. We only excised the common wall between the two urethras, and used the dorsal urethral plate of the duplicated urethra for tubularisation of the neourethra. The postoperative course was uneventful. A cystoscopy was done for suspected urogenital sinus. There was no further complaint at the third postoperative month. The TIPU technique can be successfully applied in such cases. The dorsal plate of the duplicated urethra can be used to form the neourethra.

  16. Bond diluted Ising model in 2D

    Directory of Open Access Journals (Sweden)

    Bouamrane Rachid

    2013-03-01

    Full Text Available The bond diluted Ising model is studied by Monte Carlo method. The simulation is carried out on a two dimensional square lattice with missing bonds and free boundary conditions. The aim of this work is to investigate the thermodynamical properties of this model for different disorder degree parameter σ. The critical temperature is determined from the Binder cumulant and is shown to decreases as the disorder parameter σ increases linearly.

  17. Water Metabolism of Walruses by Isotope Dilution

    DEFF Research Database (Denmark)

    Acquarone, M.; Born, E. W.; Chwalibog, A.;

    In August 2000, the hydrogen isotope dilution method was used on 7 adult male Atlantic walruses (Odobenus rosmarus rosmarus) (weight: 1197±148 kg, mean±SD, range 1013-1508 kg) at a terrestrial haul-out in Northeastern Greenland to determine their body water pool sizes and body water turnover rate...... successfully be used on walruses to estimate water metabolism as well as other metabolic parameters....

  18. Morphological variations of Mn-doped ZnO dilute magnetic semiconductors thin films grown by succesive ionic layer by adsorption reaction method.

    Science.gov (United States)

    Balamurali, Subramanian; Chandramohan, Rathinam; Karunakaran, Marimuthu; Mahalingam, Thayan; Parameswaran, Padmanaban; Suryamurthy, Nagamani; Sukumar, Arcod Anandhakrishnan

    2013-07-01

    Transparent conducting Mn-doped ZnO thin films have been prepared by successive ionic layer by adsorption reaction (SILAR) method. The deposition conditions have been optimized based on their structure and on the formation of smoothness, adherence, and stoichiometry. The results of the studies by X-ray diffraction, scanning electron microscope (SEM), reveal the varieties of structural and morphological modifications feasible with SILAR method. The X-ray diffraction patterns confirm that the ZnO:Mn has wurtzite structure. The interesting morphological variations with dopant concentration are observed and discussed. The films' quality is comparable with those grown with physical methods and is suitable for spintronic applications.

  19. Modeling of Lamb wave propagation in plate with two-dimensional phononic crystal layer coated on uniform substrate using plane-wave-expansion method

    Energy Technology Data Exchange (ETDEWEB)

    Hou Zhilin [Laboratoire de Physique des Milieux Ionises et Applications (LPMIA), Nancy University, CNRS Boulevard des Aiguillettes, BP 239 F-54506, Vandoeuvre-les-Nancy (France)], E-mail: zhilin.hou@lpmi.uhp-nancy.fr; Assouar, Badreddine M. [Laboratoire de Physique des Milieux Ionises et Applications (LPMIA), Nancy University, CNRS Boulevard des Aiguillettes, BP 239 F-54506, Vandoeuvre-les-Nancy (France)

    2008-03-17

    We show that the conversional three-dimensional plane wave expansion method can be revised to investigate the lamb wave propagation in the plate with two-dimensional phononic crystal layer coated on uniform substrate. We find that an imaginary three-dimensional periodic system can be constructed by stacking the studied plates and vacuum layers alternately, and then the Fourier series expansion can be performed. The difference between our imaginary periodic system and the true three-dimensional one is that, in our system, the Bloch feature of the wave along the thickness direction is broken. Three different systems are investigated by the proposed method as examples. The principle and reliability of the method are also discussed.

  20. Origami - Folded Plate Structures

    OpenAIRE

    Buri, Hans Ulrich

    2010-01-01

    This research investigates new methods of designing folded plate structures that can be built with cross-laminated timber panels. Folded plate structures are attractive to both architects and engineers for their structural, spatial, and plastic qualities. Thin surfaces can be stiffened by a series of folds, and thus not only cover space, but also act as load bearing elements. The variation of light and shadow along the folded faces emphasizes the plas...

  1. Stable-isotope dilution liquid chromatography-electrospray injection tandem mass spectrometry method for fast, selective measurement of S-adenosylmethionine and S-adenosylhomocysteine in plasma.

    NARCIS (Netherlands)

    Gellekink, H.; Oppenraaij-Emmerzaal, D. van; Rooij, A. van; Struys, E.A.; Heijer, M. den; Blom, H.J.

    2005-01-01

    BACKGROUND: It has been postulated that changes in S-adenosylhomocysteine (AdoHcy), a potent inhibitor of transmethylation, provide a mechanism by which increased homocysteine causes its detrimental effects. We aimed to develop a rapid and sensitive method to measure AdoHcy and its precursor S-adeno

  2. "Paraffin wax-overlay of pour plate", a method for the isolation and enumeration of purple non-sulfur bacteria.

    Science.gov (United States)

    Archana, A; Sasikala, Ch; Ramana, Ch V; Arunasri, K

    2004-12-01

    A modification of pour plate technique with an overlay of wax was used for isolation and enumeration of purple non-sulfur bacteria (PNSB) with equal efficiency as that of agar shake culture. The total count of PNSB ranged from 10(5)-10(8) CFU g dry soil(-1) and belonged to the genera of Rhodobacter, Rhodopseudomonas, Rhodocista and Rubrivivax.

  3. Philippine Sea and East Asian plate tectonics since 52 Ma constrained by new subducted slab reconstruction methods

    Science.gov (United States)

    Wu, Jonny; Suppe, John; Lu, Renqi; Kanda, Ravi

    2016-06-01

    We reconstructed Philippine Sea and East Asian plate tectonics since 52 Ma from 28 slabs mapped in 3-D from global tomography, with a subducted area of ~25% of present-day global oceanic lithosphere. Slab constraints include subducted parts of existing Pacific, Indian, and Philippine Sea oceans, plus wholly subducted proto-South China Sea and newly discovered "East Asian Sea." Mapped slabs were unfolded and restored to the Earth surface using three methodologies and input to globally consistent plate reconstructions. Important constraints include the following: (1) the Ryukyu slab is ~1000 km N-S, too short to account for ~20° Philippine Sea northward motion from paleolatitudes; (2) the Marianas-Pacific subduction zone was at its present location (±200 km) since 48 ± 10 Ma based on a >1000 km deep slab wall; (3) the 8000 × 2500 km East Asian Sea existed between the Pacific and Indian Oceans at 52 Ma based on lower mantle flat slabs; (4) the Caroline back-arc basin moved with the Pacific, based on the overlapping, coeval Caroline hot spot track. These new constraints allow two classes of Philippine Sea plate models, which we compared to paleomagnetic and geologic data. Our preferred model involves Philippine Sea nucleation above the Manus plume (0°/150°E) near the Pacific-East Asian Sea plate boundary. Large Philippine Sea westward motion and post-40 Ma maximum 80° clockwise rotation accompanied late Eocene-Oligocene collision with the Caroline/Pacific plate. The Philippine Sea moved northward post-25 Ma over the northern East Asian Sea, forming a northern Philippine Sea arc that collided with the SW Japan-Ryukyu margin in the Miocene (~20-14 Ma).

  4. Comparison of Methods for Determination of Tylosin Concentrated Solution by Several Common Acid Dilution%几种常用酸稀释液测定泰乐菌素精制液效价的方法比较

    Institute of Scientific and Technical Information of China (English)

    张金霞; 张萍; 包洁华; 郭强功

    2014-01-01

    The method used three diluted solutions, such as 0. 1 mol/L hydrochloric acid solution, 0. 05 mol/L sulfuric acid solution, 0. 033 mol/L phosphoric acid solution, Determining of tylosin concentrated solution chemical titer for comparison respectively, from the curve of the linear relationship, accuracy and contrast test results were analyzed and compared.The results showed that three kinds of solution had a good linear relationship between absorbance and concentration.(RH2=0.9997,RS2=1.0000,RP2=1.0000;n=5); and high accuracy;Results had no significant difference. We can choose different acid dilutions for determination in quality control.%分别采用0.1 mol/L盐酸溶液、0.05 mol/L硫酸溶液、0.033 mol/L磷酸溶液作稀释液测定泰乐菌素精制液化学效价,从曲线线性关系、准确度及检验结果对比方面进行分析比较。结果显示:三种溶液吸收度与浓度均呈良好的线性关系( R盐酸2=0.9997, R硫酸2=1.0000, R磷酸2=1.0000;n=5),准确度高,测定结果无明显差异,在质量控制中可以选择不同的酸稀释液进行测定。

  5. 受污染车牌字符分割方法的研究%Research on the Method of Contaminated License Plate Character Segmentation

    Institute of Scientific and Technical Information of China (English)

    沈花玉; 苗艳华; 杜青; 冯芳; 韩彬彬; 赵紫鹏; 赵志刚

    2016-01-01

    为提高对受污染车牌字符分割的有效率,提出了将现有字符分割方法中的垂直投影法和固定边界法结合的方法应用于受污染车牌字符的分割,对原始图像进行灰度化、二值化、开闭运算、去除边框、去除圆点,实验结果表明,该方法可以有效进行受污染车牌字符的分割。%To improve the efficiency of contaminated license plate character segmentation,it proposed the combined method of vertical projection method and fixed boundary method is applied to the contaminated license plate character segmentation.This metod is used to deal with the original image,grayscale, binaryzation, opening and closing operation,the removal of borders, removal of dots.The experimental results show that this method can segment contaminated license plate character effectively.

  6. Simple and sensitive analysis of histamine and tyramine in Japanese soy sauces and their intermediates using the stable isotope dilution HILIC-MS/MS method.

    Science.gov (United States)

    Todoroki, Kenichiro; Ishii, Yasuhiro; Miyauchi, Chiemi; Kitagawa, Sachiyo; Min, Jun Zhe; Inoue, Koichi; Yamanaka, Tomoyuki; Suzuki, Kuniaki; Yoshikawa, Yuko; Ohashi, Norio; Toyo'oka, Toshimasa

    2014-07-02

    We established a simple, sensitive, and reproducible method to analyze the histamine and tyramine levels in Japanese soy sauce and its mash (called moromi) using hydrophilic interaction liquid chromatography with tandem mass spectrometry (HILIC-MS/MS). Histamine and tyramine quantification was performed using their stable isotopes for electrospray ionization-tandem mass spectrometry in the selected reaction monitoring mode. The sample pretreatment process was a simple, one-step liquid-liquid extraction. HILIC separation was performed with a gradient elution of aqueous ammonium formate and acetonitrile. Because of validation tests, the linearity, the accuracies, and precisions were sufficient. The limit of detection and the limit of quantification were 0.09 and 0.29 ppm for histamine and 0.13 and 0.42 ppm for tyramine, respectively. We successfully applied this method to histamine and tyramine determination in four kinds of commercial Japanese soy sauces and also in moromi samples during soy sauce production.

  7. An application of CCD read-out technique to neutron distribution measurement using the self-activation method with a CsI scintillator plate

    Science.gov (United States)

    Nohtomi, Akihiro; Kurihara, Ryosuke; Kinoshita, Hiroyuki; Honda, Soichiro; Tokunaga, Masaaki; Uno, Heita; Shinsho, Kiyomitsu; Wakabayashi, Genichiro; Koba, Yusuke; Fukunaga, Junichi; Umezu, Yoshiyuki; Nakamura, Yasuhiko; Ohga, Saiji

    2016-10-01

    In our previous paper, the self-activation of an NaI scintillator had been successfully utilized for detecting photo-neutrons around a high-energy X-ray radiotherapy machine; individual optical pulses from the self-activated scintillator are read-out by photo sensors such as a photomultiplier tube (PMT). In the present work, preliminary observations have been performed in order to apply a direct CCD read-out technique to the self-activation method with a CsI scintillator plate using a Pu-Be source and a 10-MV linac. In conclusion, it has been revealed that the CCD read-out technique is applicable to neutron measurement around a high-energy X-ray radiotherapy machine with the self-activation of a CsI plate. Such application may provide a possibility of novel method for simple neutron dose-distribution measurement.

  8. Densitometric HPTLC method for qualitative, quantitative analysis and stability study of Coenzyme Q10 in pharmaceutical formulations utilizing normal and reversed-phase silica gel plates.

    Science.gov (United States)

    Abdel-Kader, Maged Saad; Alam, Prawez; Alqasoumi, Saleh Ibrahim

    2016-03-01

    Two simple, precise and stability-indicating densitometric HPTLC method were developed and validated for qualitative and quantitative analysis of Coenzyme Q10 in pharmaceutical formulations using normal-phase (Method I) and reversed phase (Method II) silica gel TLC plates. Both methods were developed and validated with 10×20 cm glass-backed plates coated with 0.2 mm layers of either silica gel 60 F254 (E-Merck, Germany) using hexane-ethyl acetate (8.5:1.5 v/v) as developing system (Method I) or RP-18 silica gel 60 F254 (E-Merck, Germany) using methanol-acetone (4:6 v/v) as mobile phase (Method II). Both analyses were scanned with a densitometer at 282 nm. Linearity was found in the ranges 50-800 ng/spot (r(2)=0.9989) and 50-800 ng/spot (r(2)=0.9987) for Method I and Method II respectively. Stability of Coenzyme Q10 was explored by the two methods using acid, base, hydrogen peroxide, temperature and different solvents. Due to the efficiency of the method in separating Coenzyme Q10 from other ingredients including its degradation products, it can be applied for quality control, standardization of different pharmaceutical formulations and stability study.

  9. A New Method for Decreasing Mass Limit of Detection and Increasing Number of Theoretical Plates in Capillary Electrophoresis with Amperometric Detection

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    A new method was developed to decrease the mass limit of detection (LOD) and increase the number of theoretical plates (N) in capillary electrophoresis with amperometric detection. When the single microcylinder electrode, the 10 μm ID capillary with the etched detection end and the in-capillary alignment were used, the mass LOD for phenol was reduced 124 times and N was increased 36 times in comparison with the normal situation.

  10. Approach to Deep Plate Loading Test of Self-reaction Force Method%自反力法深层平板载荷试验探讨

    Institute of Scientific and Technical Information of China (English)

    王晓伟; 林泽耿; 刘炳凯

    2014-01-01

    This article took a project of Guangdong as an example, introduced the technique of deep plate loading test of self-reaction force method in detail,and compared with the traditional method of deep plate loading test,and finally,problems that need to pay attention to deep plate loading test of self-reaction force method were put forward from the processing technology at the bottom of testing hole,keeping test hole straight,keeping stability of hole wall,and so on.%以广东某工程为例,详细介绍采用自反力法进行深层平板载荷试验测试技术,并将该方法与传统法深层平板载荷试验进行比较,最后从测试孔的孔底处理技术、测孔保直、孔壁稳定等方面提出采用自反力法进行深层平板载荷试验需要注意的问题。

  11. A Fast Monitoring Method of Oil Diluted by Fuel Based on Information Relationship%基于信息关联的润滑油燃油稀释快速监测方法研究

    Institute of Scientific and Technical Information of China (English)

    徐广; 邢志娜; 瞿军; 韩晓

    2011-01-01

    A fast monitoring method of oil diluted by fuel for army special vehicle was put forward based on information relationship, which realizes the fast analysis of the oil polluted by fuel through the analysis of physical and chemical parameters by NIR,the viscosity and flash point by physical and chemical analysis. Information relationship analysis between the using capability of lubricating oil and its physical and chemical parameters is the core of this method. The results of principal components analysis on the oil samples of two motor vehicle show that the diesel is the first parameter that influences viscosity and flash point. Through grey correlation analysis of all samples including 20 random samples, the result shows that information relationship of diesel, viscosity, flash point from the motor vehicle of same style is stable. This method combines the advantages of FT-IR as well as NlR,it provides a new method for monitoring oil diluted by fuel quickly and credibly.%针对军用特种车辆的发动机润滑油燃油稀释监测问题,提出一种基于信息关联的润滑油燃油稀释快速监测方法,即通过近红外光谱对润滑油理化指标的分析,实现对润滑油燃油污染的快速分析.其中,润滑油使用性能和理化指标之间的信息关联分析是该方法的核心.对两辆跟踪特种车辆油样信息的主成分分析结论表明润滑油燃油稀释是影响油液黏度与闪点的主要参数,对跟踪车辆及20组随机车辆油样的灰色关联分析表明同一类型车辆油液的燃油稀释、黏度、闪点三者间的信息关联程度较为稳定.该方法结合红外与近红外光谱分析的优势,为润滑油燃油稀释快速可靠的监测提供了一种新途径.

  12. Using plate mapping to examine portion size and plate composition for large and small divided plates.

    Science.gov (United States)

    Sharp, David E; Sobal, Jeffery; Wansink, Brian

    2014-12-01

    Does the size of a plate influence the serving of all items equally, or does it influence the serving of some foods - such as meat versus vegetables - differently? To examine this question, we used the new method of plate mapping, where people drew a meal on a paper plate to examine sensitivity to small versus large three-compartment divided plates in portion size and meal composition in a sample of 109 university students. The total drawn meal area was 37% bigger on large plates than small plates, which showed that the portion of plate coverage did not differ by plate size. Men and women drew bigger vegetable portions and men drew bigger meat portions on large plates when compared to small plates. These results suggest that men and women are differentially sensitive to plate size for overall meal size and for meal composition. Implications for decreasing portion size and improving meal balance are that plate size may influence portion size and change the proportions of foods served.

  13. Automated on-line column-switching high performance liquid chromatography isotope dilution tandem mass spectrometry method for the quantification of bisphenol A, bisphenol F, bisphenol S, and 11 other phenols in urine.

    Science.gov (United States)

    Zhou, Xiaoliu; Kramer, Joshua P; Calafat, Antonia M; Ye, Xiaoyun

    2014-01-01

    Human exposure to bisphenol A (BPA) is widespread. However, in recent years, bisphenol analogs such as bisphenol S (BPS) and bisphenol F (BPF) are replacing BPA in the production of some consumer products. Because human exposure to these alternative bisphenols may occur, biomonitoring of these bisphenol analogs is warranted. In the present study, we developed and validated a sensitive and selective method that uses on-line solid phase extraction coupled to high performance liquid chromatography-isotope dilution tandem mass spectrometry with peak focusing to measure BPA, BPF, BPS, and 11 other environmental phenols in urine. The method required a small amount of sample (100μL) and minimal sample pretreatment. The limits of detection were 0.03ng/mL (BPS), 0.06ng/mL (BPF), 0.10ng/mL (BPA), and ranged from 0.1ng/mL to 1.0ng/mL for the other 11 phenols. In 100 urine samples collected in 2009-2012 from a convenience group of anonymous adults in the United States, of the three bisphenols, we detected BPA at the highest frequency and median concentrations (95%, 0.72ng/mL), followed by BPS (78%, 0.13ng/mL) and BPF (55%, 0.08ng/mL). This sensitive, rugged, and labor and cost-effective method could be used for the analysis of large number of samples for epidemiologic studies.

  14. TECHNICAL DESIGN NOTE: The method for controlling dew droplets deposited on a copper plate by scattered laser light

    Science.gov (United States)

    Matsumoto, Shigeaki

    2008-01-01

    Tiny dew droplets deposited on a copper plate were controlled constantly by a developed control technique using scattered laser light for studying initial dropwise condensation. The technique employs proportional control combined with shifting movement by an integrator. The droplets were controlled for 60 min at almost constant diameters in a range from only a few micrometers to tens of micrometers and were almost hemispherical in the initial condensation at room temperature.

  15. New Method for Hard Sludge Removal from Tube Plate Surfaces: The AREVA Enhanced Inner Bundle Lancing Process

    Energy Technology Data Exchange (ETDEWEB)

    Stoss, J.; Santibanez, M.

    2014-07-01

    AREVA is currently conducting the final steps to start-up an enhanced technology to remove hard sludge deposits from the inner bundle area of the tube sheets. This inner bundle area at the top of the tube plate is the location with the lowest flow velocity of the circulating water at the secondary closed loop. The reduced water speed causes increased accumulation of ferrite oxides at these locations. (Author)

  16. Atomic displacements in bcc dilute alloys

    Indian Academy of Sciences (India)

    Hitesh Sharma; S Prakash

    2007-04-01

    We present here a systematic investigation of the atomic displacements in bcc transition metal (TM) dilute alloys. We have calculated the atomic displacements in bcc (V, Cr, Fe, Nb, Mo, Ta and W) transition metals (TMs) due to 3d, 4d and 5d TMs at the substitutional site using the Kanzaki lattice static method. Wills and Harrison interatomic potential is used to calculate the atomic force constants, the dynamical matrix and the impurity-induced forces. We have thoroughly investigated the atomic displacements using impurities from 3d, 4d and 5d series in the same host metal and the same impurity in different hosts. We have observed a systematic pattern in the atomic displacements for Cr-, Fe-, Nb-, Mo-, Ta- and W-based dilute alloys. The atomic displacements are found to increase with increase in the number of d electrons for all alloys considered except for V dilute alloys. The 3d impurities are found to be more easily dissolved in the 3d host metals than 4d or 5d TMs whereas 4d and 5d impurities show more solubility in 4d and 5d TMs. In general, the relaxation energy calculation suggests that impurities may be easily solvable in 5d TM hosts when compared to 3d or 4d TMs.

  17. Infiltration as Ventilation: Weather-Induced Dilution

    Energy Technology Data Exchange (ETDEWEB)

    Sherman, Max H. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Turner, William J.N. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Walker, Iain S. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2011-06-01

    The purpose of outdoor air ventilation is to dilute or remove indoor contaminants to which occupants are exposed. It can be provided by mechanical or natural means. In most homes, especially older homes, weather-driven infiltration provides the dominant fraction of the total ventilation. As we seek to provide good indoor air quality at minimum energy cost, it is important to neither over-ventilate nor under-ventilate. Thus, it becomes critically important to evaluate correctly the contribution infiltration makes to the total outdoor air ventilation rate. Because weather-driven infiltration is dependent on building air leakage and weather-induced pressure differences, a given amount of air leakage will provide different amounts of infiltration. Varying rates of infiltration will provide different levels of contaminant dilution and hence effective ventilation. This paper derives these interactions and then calculates the impact of weather-driven infiltration for different climates. A new “N-factor” is introduced to provide a convenient method for calculating the ventilation contribution of infiltration for over 1,000 locations across North America. The results of this work could be used in indoor air quality standards (specifically ASHRAE 62.2) to account for the contribution of weather-driven infiltration towards the dilution of indoor pollutants.

  18. Structural health monitoring method based on the entropy of an ultrasonic sensor network for a plate-like structure

    Science.gov (United States)

    Rojas, Erick; Baltazar, Arturo

    2015-03-01

    Piezoelectric ultrasonic sensors used to propagate guided waves can potentially be implemented to inspect large areas in engineering structures. However, the inherent dispersion and noise of the guided acoustic signals, multiple echoes in the plate as well as a lack of an approximate or exact model limits their use as a continuous structural health monitoring system. In this work, the implementation of a network of piezoelectric sensors randomly placed on a plate-like structure to detect and locate artificial damage is studied. A sensor network of randomly located 1MHz transducers working in a pitch-catch configuration was set on an aluminum thin plate 1.9 mm in thickness. Signals were analyzed in time-scale domain by the continuous wavelet transform. The objectives in this work were twofold, first to develop a damage index using the entropy of the ultrasonic waves generated by a sensor network; and second to implement time of arrival (TOA) and time-difference of arrival (TDOA) algorithms on the gathered signals for damage location of an artificial circular discontinuity. Our preliminary test results show that the proposed methodology provides sufficient information for damage detection which, once combined with the TOA and TDOA algorithms, allows localization of the damage.

  19. Detection of plating defects using ultrasonic and eddy current test methods; Nachweis von Plattierungsfehlern mit Ultraschall- und Wirbelstromverfahren

    Energy Technology Data Exchange (ETDEWEB)

    Waidele, H.; Knoch, P. [MPA, Univ. Stuttgart (Germany); Gersinska, R. [BfS Salzgitter (Germany); Brenner, W.; Seidenkranz, T. [TUeV Sued (Germany); Csapo, G.; Just, T. [TUeV Nord (Germany); Weiss, R. [IzfP Saarbruecken (Germany); Rathgeb, W. [IntelligeNDT, Erlangen (Germany)

    2004-07-01

    The validity of ultrasonic and eddy current testing of austenitic platings of reactor pressure vessels was investigated in the context of a project funded by the Federal Radiation Protection Office (Bundesamt fuer Strahlenschutz). In the first phase, test specimens with natural defects were fabricated at MPA Stuttgart; in the second phase, plating defects were introduced in a MPA large-size vessel. Measurements showed that most plating defects will be detected by standard ultrasonic testing. The highest accuracy was achieved by a combination of ultrasonic and eddy current testing. (orig.) [German] Im Rahmen eines vom Bundesamt fuer Strahlenschutz gefoerderten Vorhabens wurde die Aussagefaehigkeit von Ultraschall- und Wirbelstrompruefungen an austenitischen Plattierungen von Reaktordruckbehaeltern untersucht. In der ersten Phase des Vorhabens wurden an der MPA Stuttgart Testkoerper mit natuerlichen Fehlern im Plattierungsbereich gefertigt, in einer zweiten Phase wurden Plattierungsfehler in den MPA-Grossbehaelter eingebracht. Die Messungen haben gezeigt, dass die meisten Plattierungsfehler mit Ultraschall-Standardprueftechniken nachweisbar sind, wobei die groesste Aussagekraft bei einer Kombination von Ultraschall- und Wirbelstrompruefung gegeben ist. (orig.)

  20. Parametric study on supersonic flutter of angle-ply laminated plates using shear deformable finite element method

    Institute of Scientific and Technical Information of China (English)

    Wei Xia; Qiao Ni

    2011-01-01

    The influence of fiber orientation,flow yaw angle and length-to-thickness ratio on flutter characteristics of angle-ply laminated plates in supersonic flow is studied by finite element approach.The structural model is established using the Reissner-Mindlin theory in which the transverse shear deformation is considered.The aerodynamic pressure is evaluated by the quasi-steady first-order piston theory.The equations of motion are formulated based on the principle of virtual work.With the harmonic motion assumption,the flutter boundary is determined by solving a series of complex eigenvalue problems.Numerical study shows that (1)The flutter dynamic pressure and the coalescence of flutter modes depend on fiber orientation,flow yaw angle and length-to-thickness ratio; (2) The laminated plate with all fibers aligned with the flow direction gives the highest flutter dynamic pressure,but a slight yawing of the flow from the fiber orientation results in a sharp decrease of the flutter dynamic pressure; (3) The angle-ply laminated plate with fiber orientation angle equal to flow yaw angle gives high flutter dynamic pressure,but not the maximum flutter dynamic pressure; (4) With the decrease of length-to-thickness ratio,an adverse effect due to mode transition on the flutter dynamic pressure is found.

  1. Research of Preloading Method for Axial Piston Pump with Swash Plate%斜盘式轴向柱塞泵预紧方式研究

    Institute of Scientific and Technical Information of China (English)

    张伟; 吉利科; 朱琳

    2015-01-01

    在斜盘式轴向柱塞泵中,通常采用弹簧对缸体与配油盘进行中心预紧,产生的预压力压紧保持架使柱塞与滑靴回程。目前常见为碟形弹簧及普通螺旋形弹簧,该文对两种弹簧进行比较,同时对使用上述两种弹簧的几种典型中心弹簧预紧方式进行比较、分析,给出在不同场合建议选用的预紧方式。%In general, the cylinder and valve plate is preloaded by spring in axial piston pump with swash plate. Meanwhile the spring can preload the retainer to make the piston and piston shoe back to the swash plate. The structure is widely used in axial piston pump. At present, the disk spring and coil spring are used often. In this paper, several typical preloading methods with the two types of spring above are dis-cussed and analyzed, and the proper preloading method is suggested in different specific applications.

  2. 镀金引线SMD焊接工艺方法探讨%Soldering Method Research of SMD with Golding-plated Lead

    Institute of Scientific and Technical Information of China (English)

    杨艺峰; 车飞; 周承平; 吴夏凯

    2014-01-01

    With high reliability requirements of weapon system and improvement of the basis level of domestic electron components, more and more ceramic packaging of SMD apply to the military product. The component lead is mostly plated with gold, but the gold coating must be removed when the component is to be soldered. Compare and analyze the soldering quality of solder joints of golding-plated lead SMT components using four soldering methods, get the best soldering method for golding-plated lead components.%随着武器系统高可靠性要求的不断加强和国产电子元器件基础水平的不断提高,越来越多的陶瓷封装军用SMD开始应用于型号产品。该类器件的引线多采用镀金工艺,焊接时必须进行除金处理。用四种焊接工艺方法对镀金引脚器件焊接,对比分析器件焊点的焊接质量,得出镀金引脚器件最佳焊接工艺方法。

  3. Bending and free vibration analysis of functionally graded plates using new eight-unknown shear deformation theory by finite-element method

    Science.gov (United States)

    Van Long, Nguyen; Quoc, Tran Huu; Tu, Tran Minh

    2016-12-01

    In this paper, a new eight-unknown shear deformation theory is developed for bending and free vibration analysis of functionally graded plates by finite-element method. The theory based on full 12-unknown higher order shear deformation theory simultaneously satisfies zeros transverse stresses at top and bottom surfaces of FG plates. A four-node rectangular element with 16 degrees of freedom per node is used. Poisson's ratios, Young's moduli, and material densities vary continuously in thickness direction according to the volume fraction of constituents which is modeled as power-law functions. Results are verified with available results in the literature. Parametric studies are performed for different power-law indices, side-to-thickness ratios.

  4. An eco-friendly strategy, using on-line monitoring and dilution coupled to a second-order chemometric method, for the construction of dissolution curves of combined pharmaceutical associations.

    Science.gov (United States)

    Calvo, Natalia L; Maggio, Rubén M; Kaufman, Teodoro S

    2014-02-01

    A simple, precise, economic and minimally operator-dependent method was developed under green analytical chemistry principles, for the simultaneous construction of the dissolution curves of a pharmaceutical association in short time and without employing organic solvents, allowing important savings of labor and resources. The carvedilol (CAR) and hydrochlorothiazide (HCT) combined formulation was employed as a model. The method (OD/UV-MCR) involves on-line sample dilution (OD) and UV detection of the analytes, coupled to multivariate curve resolution with alternating least squares (MCR-ALS). OD/UV-MCR proved to be robust and was successfully validated in accordance to ICH guidelines, fulfilling acceptance criteria for specificity (r(2) of spectral correlation>0.950), linearity [r>0.999 (N=25) in the ranges 1.00-31.1mg l(-1) and 0.51-15.2mg l(-1) for CAR and HCT, respectively] and precision (RSDCAR-HCT pharmaceutical association, belonging to a couple of different brands, employing Moore and Flanner's f2 similarity indicator.

  5. USE OF A MICRO TITLE PLATE DILUTION ASSAY TO MEASURE ACTIVITY OF ANTIFUNGAL COMPOUNDS AGAINST Mycosphaerella Fijiensis, MORELET. UTILIZACIÓN DE UN ENSAYO DE DILUCIÓN EN MICROPLATOS PARA MEDIR LA ACTIVIDAD ANTIFÚNGICA DE SUSTANCIAS CONTRA Mycosphaerella fijiensis, MORELET.

    Directory of Open Access Journals (Sweden)

    Jorge Enrique Peláez Montoya

    2006-12-01

    Full Text Available Black Sigatoka, caused by the fungus Mycosphaerella fijiensis is the most important disease in banana plantations. The fungus is controlled mainly by fungicide applications with an annual cost of about 350 million dollars in Latin and Central America. Due to the appearance of resistant strains and to the economical and environmental impact caused by the extensive use of fungicides, accurate methods are necessary for monitoring the fungal sensitivity to these agents. In this paper we describe the standarization of a method based on microplate dilutions that measures IC50 of different antifungal compounds against single ascospore cultures of M. fijiensis. The method was used to measure the sensitivity of 30 strains collected from different regions in Colombia against Propiconazol, Benomyl and Azoxystrobin. Used at a larger scale, this method could be useful to monitor M. fijiensis sensitivity against fungicides and to search for new compounds with activity against the fungus.La Sigatoka negra, causada por el hongo Mycosphaerella fijiensis, es la enfermedad más importante que afecta plantaciones de banano y plátano. El hongo es controlado principalmente mediante fungicidas químicos con un costo anual de cerca de 350 millones de dólares para América latina y 25 millones de dólares para Colombia. Debido al desarrollo de cepas del hongo resistentes a los fungicidas y a las consecuencias que para el medio ambiente tiene su uso intensivo, es importante el desarrollo de métodos que permitan monitorear de una manera precisa la aparición de resistencia. También es de gran utilidad disponer de un método que permita evaluar en forma sencilla la actividad de nuevas sustancias contra el hongo. En este artículo describimos la estandarización de un método basado en diluciones en microplatos que permite determinar la IC50 de diversos compuestos antifungicos contra cultivos monospóricos de M. fijiensis. Para su validación, el método fue utilizado

  6. Comparison of Petrifilm Staph Express Count System with the bacteriological analytical manual direct-plating method for enumeration of Staphylococcus aureus in artificially contaminated hard cheese.

    Science.gov (United States)

    Fedio, Willis M; Wendakoon, Chitra N; Zapata, Ruben; Carrillo, Christina; Browning, Paul

    2008-01-01

    The 3M Petrifilm Staph Express Count System was compared with the U.S. Food and Drug Administration's Bacteriological Analytical Manual (BAM) direct-plate count method for the enumeration of Staphylococcus aureus in 6 types of artificially contaminated hard cheese (Asiago, Cheddar, Gruyère, Parmesan, Romano, and Swiss). Five different samples of each cheese type were inoculated with S. aureus (ATCC 25923) to achieve low, medium, and high inoculum levels. S. aureus was enumerated by the Petrifilm and BAM methods, and the results were compared. Multivariate analysis of variance revealed no significant differences (P<0.05) between the 2 methods. The Petrifilm method compared favorably with the BAM procedure. The rapid method was more convenient to use, considerably faster, and less expensive to perform than the BAM method.

  7. The optimization of molybdenum back contact films for Cu(In,Ga)Se{sub 2} solar cells by the cathodic arc ion plating method

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Yong Ki, E-mail: choyk@kitech.re.kr [Heat Treatment and Surface Engineering R and D Group, Korea Institute of Industrial Technology, Incheon 406-840 (Korea, Republic of); Department of Physics, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Kim, Gang Sam; Song, Young Sik; Lim, Tae Hong [Heat Treatment and Surface Engineering R and D Group, Korea Institute of Industrial Technology, Incheon 406-840 (Korea, Republic of); Jung, Donggeun [Department of Physics, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of)

    2013-12-02

    Molybdenum back contact films for Cu(In,Ga)Se{sub 2} (CIGS) solar cells have been deposited using DC magnetron sputtering methods. The electronic pathway properties of the molybdenum film have been highly dependent on the working gas pressure in magnetron sputtering, which should be carefully controlled to obtain high conductivity and adhesion. A coating method, cathodic arc ion plating, was used for molybdenum back contact electrode fabrication. The aim of this work was to find a metallization method for CIGS solar cells, which has less sensitivity on the working pressure. The resistivity, grain size, growth structures, stress, and efficiency of the films in CIGS solar cells were investigated. The results reveal that the growth structures of the molybdenum films mainly affect the conductivity. The lowest electrical resistivity of the ion-plated molybdenum films was 6.9 μΩ-cm at a pressure of 0.7 Pa. The electrical resistivity variation showed a gently increasing slope with linearity under a working gas pressure of 13.3 Pa. However, a high value of the residual stress of over 1.3 GPa was measured. In order to reduce stress, titanium film was selected as the buffer layer material, and the back contact films were optimized by double-layer coating of two kinds of hetero-materials with arc ion plating. CIGS solar cells prepared molybdenum films to measure the efficiency and to examine the effects of the back contact electrode. The resistivity, grain size, and surface morphology of molybdenum films were measured by four-point probe, X-ray diffraction, and a scanning electron microscope. The residual stress of the films was calculated from differences in bending curvatures measured using a laser beam. - Highlights: • Molybdenum back contact films for Cu(In,Ga)Se{sub 2} solar cells were prepared by the cathodic arc ion plating. • The lowest electrical resistivity of molybdenum film was 6.9 μΩ-cm. • Titanium buffer layer reduced the compressive residual stress

  8. The Carlina-type diluted telescope: Stellar fringes on Deneb

    CERN Document Server

    Coroller, H Le; Hespeels, F; Arnold, L; Andersen, T; Deram, P; Ricci, D; Berio, P; Blazit, A; Clausse, J-M; Guillaume, C; Meunier, J-P; Regal, X; Sottile, R

    2014-01-01

    Context. The performance of interferometers has largely been increased over the last ten years. But the number of observable objects is still limited due to the low sensitivity and imaging capability of the current facilities. Studies have been done to propose a new generation of interferometers. Aims. The Carlina concept studied at the Haute-Provence Observatory consists in an optical interferometer configured as a diluted version of the Arecibo radio telescope: above the diluted primary mirror made of fixed co-spherical segments, a helium balloon or cables suspended between two mountains and/or pylons, carries a gondola containing the focal optics. This concept does not require delay lines. Methods. Since 2003, we have been building a technical demonstrator of this diluted telescope. The main goals of this project were to find the opto-mechanical solutions to stabilize the optics attached under cables at several tens of meters above the ground, and to characterize this diluted telescope under real condition...

  9. Temperature field of steel plate cooling process after plate rolling

    Directory of Open Access Journals (Sweden)

    Huijun Feng, Lingen Chen, Fengrui Sun

    2015-01-01

    Full Text Available Based on numerical calculation with Matlab, the study on cooling process after plate rolling is carried out, and the temperature field distribution of the plate varying with the time is obtained. The effects of the plate thickness, final rolling temperature, cooling water temperature, average flow rate of the cooling water, carbon content of the plate and cooling method on the plate surface and central temperatures as well as final cooling temperature are discussed. For the same cooling time, the plate surface and central temperatures as well as their temperature difference increase; with the decrease in rolling temperature and the increase in average flow rate of the cooling water, the plate surface and central temperatures decrease. Compared with the single water cooling process, the temperature difference between the plate centre and surface based on intermittent cooling is lower. In this case, the temperature uniformity of the plate is better, and the corresponding thermal stress is lower. The fitting equation of the final cooling temperature with respect to plate thickness, final rolling temperature, cooling water temperature and average flow rate of the cooling water is obtained.

  10. Comparing the mannitol-egg yolk-polymyxin agar plating method with the three-tube most-probable-number method for enumeration of Bacillus cereus spores in raw and high-temperature, short-time pasteurized milk.

    Science.gov (United States)

    Harper, Nigel M; Getty, Kelly J K; Schmidt, Karen A; Nutsch, Abbey L; Linton, Richard H

    2011-03-01

    The U.S. Food and Drug Administration's Bacteriological Analytical Manual recommends two enumeration methods for Bacillus cereus: (i) standard plate count method with mannitol-egg yolk-polymyxin (MYP) agar and (ii) a most-probable-number (MPN) method with tryptic soy broth (TSB) supplemented with 0.1% polymyxin sulfate. This study compared the effectiveness of MYP and MPN methods for detecting and enumerating B. cereus in raw and high-temperature, short-time pasteurized skim (0.5%), 2%, and whole (3.5%) bovine milk stored at 4°C for 96 h. Each milk sample was inoculated with B. cereus EZ-Spores and sampled at 0, 48, and 96 h after inoculation. There were no differences (P > 0.05) in B. cereus populations among sampling times for all milk types, so data were pooled to obtain overall mean values for each treatment. The overall B. cereus population mean of pooled sampling times for the MPN method (2.59 log CFU/ml) was greater (P plate count method (1.89 log CFU/ml). B. cereus populations in the inoculated milk samples ranged from 2.36 to 3.46 and 2.66 to 3.58 log CFU/ml for inoculated milk treatments for the MYP plate count and MPN methods, respectively, which is below the level necessary for toxin production. The MPN method recovered more B. cereus, which makes it useful for validation research. However, the MYP plate count method for enumeration of B. cereus also had advantages, including its ease of use and faster time to results (2 versus 5 days for MPN).

  11. A Visualization Method for Corrosion Damage on Aluminum Plates Using an Nd:YAG Pulsed Laser Scanning System

    Directory of Open Access Journals (Sweden)

    Inbok Lee

    2016-12-01

    Full Text Available This paper proposes a non-contact nondestructive evaluation (NDE technique that uses laser-induced ultrasonic waves to visualize corrosion damage in aluminum alloy plate structures. The non-contact, pulsed-laser ultrasonic measurement system generates ultrasonic waves using a galvanometer-based Q-switched Nd:YAG laser and measures the ultrasonic waves using a piezoelectric (PZT sensor. During scanning, a wavefield can be acquired by changing the excitation location of the laser point and measuring waves using the PZT sensor. The corrosion damage can be detected in the wavefield snapshots using the scattering characteristics of the waves that encounter corrosion. The structural damage is visualized by calculating the logarithmic values of the root mean square (RMS, with a weighting parameter to compensate for the attenuation caused by geometrical spreading and dispersion of the waves. An intact specimen is used to conduct a comparison with corrosion at different depths and sizes in other specimens. Both sides of the plate are scanned with the same scanning area to observe the effect of the location where corrosion has formed. The results show that the damage can be successfully visualized for almost all cases using the RMS-based functions, whether it formed on the front or back side. Also, the system is confirmed to have distinguished corroded areas at different depths.

  12. A Visualization Method for Corrosion Damage on Aluminum Plates Using an Nd:YAG Pulsed Laser Scanning System.

    Science.gov (United States)

    Lee, Inbok; Zhang, Aoqi; Lee, Changgil; Park, Seunghee

    2016-12-16

    This paper proposes a non-contact nondestructive evaluation (NDE) technique that uses laser-induced ultrasonic waves to visualize corrosion damage in aluminum alloy plate structures. The non-contact, pulsed-laser ultrasonic measurement system generates ultrasonic waves using a galvanometer-based Q-switched Nd:YAG laser and measures the ultrasonic waves using a piezoelectric (PZT) sensor. During scanning, a wavefield can be acquired by changing the excitation location of the laser point and measuring waves using the PZT sensor. The corrosion damage can be detected in the wavefield snapshots using the scattering characteristics of the waves that encounter corrosion. The structural damage is visualized by calculating the logarithmic values of the root mean square (RMS), with a weighting parameter to compensate for the attenuation caused by geometrical spreading and dispersion of the waves. An intact specimen is used to conduct a comparison with corrosion at different depths and sizes in other specimens. Both sides of the plate are scanned with the same scanning area to observe the effect of the location where corrosion has formed. The results show that the damage can be successfully visualized for almost all cases using the RMS-based functions, whether it formed on the front or back side. Also, the system is confirmed to have distinguished corroded areas at different depths.

  13. Dilution Refrigeration of Multi-Ton Cold Masses

    CERN Document Server

    Wikus, P; CERN. Geneva

    2007-01-01

    Dilution refrigeration is the only means to provide continuous cooling at temperatures below 250 mK. Future experiments featuring multi-ton cold masses require a new generation of dilution refrigeration systems, capable of providing a heat sink below 10 mK at cooling powers which exceed the performance of present systems considerably. This thesis presents some advances towards dilution refrigeration of multi-ton masses in this temperature range. A new method using numerical simulation to predict the cooling power of a dilution refrigerator of a given design has been developed in the framework of this thesis project. This method does not only allow to take into account the differences between an actual and an ideal continuous heat exchanger, but also to quantify the impact of an additional heat load on an intermediate section of the dilute stream. In addition, transient behavior can be simulated. The numerical model has been experimentally verified with a dilution refrigeration system which has been designed, ...

  14. Water Metabolism of Walruses by Isotope Dilution

    DEFF Research Database (Denmark)

    Acquarone, M.; Born, E. W.; Chwalibog, A.

    In August 2000, the hydrogen isotope dilution method was used on 7 adult male Atlantic walruses (Odobenus rosmarus rosmarus) (weight: 1197±148 kg, mean±SD, range 1013-1508 kg) at a terrestrial haul-out in Northeastern Greenland to determine their body water pool sizes and body water turnover rates...... was sampled via an epidural catheter, at regular intervals, for up to seven hours after the initial enrichment to assess isotope equilibration in the body water pools. Five individuals returned to the haul-out after feeding trips of varying duration (158±86 hr, 44-287 hr) where they were immobilized again...

  15. Modeling of dilute and dense dispersed fluid-particle flow

    Energy Technology Data Exchange (ETDEWEB)

    Laux, Harald

    1998-08-01

    finite volume method. For the numerical solution of the discretized equations a new algorithm that is based on the SIMPLE algorithm is developed. The new algorithm treats the particle phase as fully compressible. The algorithm is therefore referred to as compressible dispersed phase method (CDP). The CDP method solves the particle volume fraction from the equation-of-state of the particle phase, and both the equation-of-state and the particle continuity equation are always fulfilled simultaneously. Several types of industrial multiphase flows are studied and it is demonstrated that the two-fluid model solved with the CDP method produces stable and physically reliable solutions. First, the flow of sand and the heap building in an hourglass is computed. By means of an comprehensive parameter study it is shown that whereas the instantaneous equations without frictional stress modeling predict mass flow rates in the hourglass orifice that are in good agreement with the empirical Beverloo correlation, only with the frictional stress model realistic shapes of the heap of sand are obtained. A similar effect on the shape of the bulk particles is shown for the sediment bed in a sedimentation column. Second, the flow in two cold gas-fluidized beds is computed. It is shown that the predicted motion and characteristics of large scale bubbles in a bed with a central jet are in good agreement with classical analytical results and available experimental results. It is also shown that the model predicts spontaneous bubble formation in an uniformly fluidized bed. Third, a liquid-particle system is studied, that is, the settling convection in an inclined parallel plate settler. The computations are in excellent agreement with measurements carried out in our laboratory and analytical theories. However, the results suggest that the kinetic theory of granular material needs modification if applied to liquid-particle suspensions. Finally, the turbulence model is applied to three test cases

  16. MULTIVARIABLE WAVELET FINITE ELEMENT METHOD FOR THIN PLATE ANALYSIS%薄板的多变量小波有限元分析

    Institute of Scientific and Technical Information of China (English)

    张兴武; 陈雪峰; 王修专; 何正嘉

    2011-01-01

    Based on B-spline wavelet on the interval (BSWI) and the generalized potential variational principle, a new multivariable wavelet finite element method with two kinds of variables was proposed in the paper. The new corresponding elements for square thin plate, skew thin plate and trapezoidal thin plate were constructed. Firstly, formulations were derived from multivariable generalized potential energy functional. Then the matrix equation of thin plate was obtained by using BSWI as trial function. In this study, the generalized stress and strain were interpolated separately, so differentiation of displacement in traditional method of stress calculation was avoided, and the calculation error was reduced. Besides, the good approximation property of B-spline wavelet on the interval can further guarantee the solving accuracy. Finally, several numerical examples for bending and vibration analysis of square and skew thin plate verified the efficiency and superiority in solving generalized stress.%基于区间B样条小波和广义变分原理,提出了多变量小波有限元法,构造了一种新的薄板多变量小波有限单元.由广义变分原理推导结构的多变量有限元列式,区间B样条小波尺度函数作为插值函数构造的多变量小波有限元法中,广义应力和应变被作为独立变量进行插值,避免了传统方法中应力应变求解的微分运算,减小了计算误差.区间B样条小波良好的数值逼近性能可进一步保证求解精度.通过方形薄板、斜形薄板以及梯形薄板的弯曲和振动分析,验证了此方法的有效性和在广义应力求解中的优越性.

  17. Strongyloides stercoralis: a field-based survey of mothers and their preschool children using ELISA, Baermann and Koga plate methods reveals low endemicity in western Uganda.

    Science.gov (United States)

    Stothard, J R; Pleasant, J; Oguttu, D; Adriko, M; Galimaka, R; Ruggiana, A; Kazibwe, F; Kabatereine, N B

    2008-09-01

    To ascertain the current status of strongyloidiasis in mothers and their preschool children, a field-based survey was conducted in western Uganda using a combination of diagnostic methods: ELISA, Baermann concentration and Koga agar plate. The prevalence of other soil-transmitted helminthiasis and intestinal schistosomiasis were also determined. In total, 158 mothers and 143 children were examined from five villages within Kabale, Hoima and Masindi districts. In mothers and children, the general prevalence of strongyloidiasis inferred by ELISA was approximately 4% and approximately 2%, respectively. Using the Baermann concentration method, two parasitologically proven cases were encountered in an unrelated mother and child, both of whom were sero-negative for strongyloidiasis. No infections were detected by Koga agar plate method. The general level of awareness of strongyloidiasis was very poor ( < 5%) in comparison to schistosomiasis (51%) and ascariasis (36%). Strongyloidiasis is presently at insufficient levels to justify inclusion within a community treatment programme targeting maternal and child health. Better epidemiological screening is needed, however, especially identifying infections in HIV-positive women of childbearing age. In the rural clinic setting, further use of the Baermann concentration method would appear to be the most immediate and pragmatic option for disease diagnosis.

  18. An application of CCD read-out technique to neutron distribution measurement using the self-activation method with a CsI scintillator plate

    Energy Technology Data Exchange (ETDEWEB)

    Nohtomi, Akihiro, E-mail: nohtomi@hs.med.kyushu-u.ac.jp [Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582 (Japan); Kurihara, Ryosuke; Kinoshita, Hiroyuki; Honda, Soichiro; Tokunaga, Masaaki; Uno, Heita [Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582 (Japan); Shinsho, Kiyomitsu [Graduate School of Human Sciences, Tokyo Metropolitan University, 7-2-10 Higashi-oku, Arakawa-ku, Tokyo 116-8551 (Japan); Wakabayashi, Genichiro [Atomic Energy Research Institute, Kinki University, 3-4-1 Kowakae, Higashiosaka-shi, Osaka 577-8502 (Japan); Koba, Yusuke [National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba-shi, Chiba 263-8555 (Japan); Fukunaga, Junichi; Umezu, Yoshiyuki; Nakamura, Yasuhiko [Department of Radiology, Kyushu University Hospital, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582 (Japan); Ohga, Saiji [Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582 (Japan)

    2016-10-01

    In our previous paper, the self-activation of an NaI scintillator had been successfully utilized for detecting photo-neutrons around a high-energy X-ray radiotherapy machine; individual optical pulses from the self-activated scintillator are read-out by photo sensors such as a photomultiplier tube (PMT). In the present work, preliminary observations have been performed in order to apply a direct CCD read-out technique to the self-activation method with a CsI scintillator plate using a Pu-Be source and a 10-MV linac. In conclusion, it has been revealed that the CCD read-out technique is applicable to neutron measurement around a high-energy X-ray radiotherapy machine with the self-activation of a CsI plate. Such application may provide a possibility of novel method for simple neutron dose-distribution measurement. - Highlights: • Preliminary observations have been performed by a CCD for the CsI self-activation method. • It has been revealed that the CCD read-out technique is applicable to neutron measurement. • Such application may provide a novel method for simple neutron distribution measurement.

  19. Boiling heat transfer in dilute emulsions

    CERN Document Server

    Roesle, Matthew Lind

    2013-01-01

    Boiling Heat Transfer in Dilute Emulsions synthesizes recent advances and established understanding on the subject of boiling in dilute emulsions. Experimental results from various sources are collected and analyzed, including contemporary experiments that correlate visualization with heat transfer data. Published models of boiling heat transfer in dilute emulsions, and their implementation, are described and assessed against experimental data.

  20. Dynamic analysis of isotropic nanoplates subjected to moving load using state-space method based on nonlocal second order plate theory

    Energy Technology Data Exchange (ETDEWEB)

    Nami, Mohammad Rahim [Shiraz University, Shiraz, Iran (Iran, Islamic Republic of); Janghorban, Maziar [Islamic Azad University, Marvdash (Iran, Islamic Republic of)

    2015-06-15

    In this work, dynamic analysis of rectangular nanoplates subjected to moving load is presented. In order to derive the governing equations of motion, second order plate theory is used. To capture the small scale effects, the nonlocal elasticity theory is adopted. It is assumed that the nanoplate is subjected to a moving concentrated load with the constant velocity V in the x direction. To solve the governing equations, state-space method is used to find the deflections of rectangular nanoplate under moving load. The results obtained here reveal that the nonlocality has significant effect on the deflection of rectangular nanoplate subjected to moving load.