Academic literature on the topic 'Test tube caps'
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Journal articles on the topic "Test tube caps"
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Lichorobiec, Stanislav, and Lucia Figuli. "Shaped-Cumulative Charge as a Pyrotechnic Mean for a Pipe Bomb Deactivation." Key Engineering Materials 755 (September 2017): 65–74. http://dx.doi.org/10.4028/www.scientific.net/kem.755.65.
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The aim of solved problem is a development of a new invasive means for improvised explosive devices deactivation. The idea is a quick and reliable disposal of improvised explosive device with construction system as a tube bombe. Such tube bomb has to be deactivated, dismantled and to do not explode. The development of shaped – cumulative charge was conceptually solved in a way to pushed down metal end caps of the tube bomb, to pick up explosive with a detonating fuse and to prevent from its explosion. Dismantled parts put to forensic test, for the improvised explosive device constructer revelation.
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FUJIKAWA, HIROSHI, SATOSHI MOROZUMI, GLEN H. SMERAGE, and ARTHUR A. TEIXEIRA. "Comparison of Capillary and Test Tube Procedures for Analysis of Thermal Inactivation Kinetics of Mold Spores." Journal of Food Protection 63, no. 10 (October 1, 2000): 1404–9. http://dx.doi.org/10.4315/0362-028x-63.10.1404.
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Characteristics of capillary and test tube procedures for thermal inactivation kinetic analysis of microbial cells were studied for mold spores. During heating, capillaries were submerged in a water bath and test tubes were held with their caps positioned above the level of the heating medium. Thermal inactivation curves of Aspergillus niger spores in capillaries at around 60°C consisted of a shoulder and a fast linear decline, whereas curves in test tubes consisted of a shoulder, a fast linear decline, and a horizontal tail. There were no significant differences in values of the rate and the delay of fast declines in curves between the procedures. Some experiments were done to clarify the cause for tailing with test tubes. There were no tails with test tubes whose inner walls were not contaminated by A. niger spores, suggesting that tails arise from A. niger spores contaminating the inner walls of test tubes. Temperature of the inner wall at the level of a heating medium was lower than that of the medium. Further, there were no tails for test tubes submerged in the heating medium. These results showed that the reason for survival of contaminants on the upper wall of test tubes was that cells were not subjected to sufficient inactivation temperature. Finally, thermal inactivation curves of A. niger spores in capillaries at various constant temperatures were studied. Curves consisted of a shoulder and a fast linear decline at 57°C and above, whereas curves at below 57°C consisted of a shoulder, a fast linear decline, and a sloping tail.
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Santana, José Raniere Ferreira de, Renato Paiva, Ana Valéria de Souza, and Lenaldo Muniz de Oliveira. "Effect of different culture tube caps and concentrations of activated charcoal and sucrose on in vitro growth and budding induction of Annona glabra L." Ciência e Agrotecnologia 35, no. 5 (October 2011): 916–23. http://dx.doi.org/10.1590/s1413-70542011000500008.
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The present work evaluated the effects of different types of culture flask seals and varying concentrations of sucrose and activated charcoal on the in vitro induction and growth of buds of Annona glabra L.; an edible fruit-producing species popularly known as "araticum". Nodal segments obtained from A. glabra plants maintained in green houses were surface sterilized and inoculated into a WPM culture medium solidified with 7 g L-1 of agar and supplemented with sucrose (0.00; 29.21; 58.63 and 116.84 mM), activated charcoal (0.0 and 2.0 g L-1), and 250 mg L-1 benomyl. In addition to the varying concentrations of sucrose and activated charcoal, we evaluated the efficiency of two types of test tube seals: PVC film, and cotton plugs. All possible combinations of caps and nutrient media were tested with 4 repetitions with 5 tubes each, evaluating the number of buds, the percentage of explant responses, the number of expanded leaves per bud, the length of the largest leaves, leaf abscission, and the length and dry weight of the buds. The type of seal influenced organogenesis in nodal segments of A. glabra, and no bud induction was observed in the absence of sucrose. The largest number of expanded leaves were obtained when 58.42 mM of sucrose was used in tubes sealed with cotton plugs, and leaf abscission was halved in the presence of activated charcoal. The greatest bud length and dry weight were obtained in tubes sealed with cotton plugs and in the presence of activated charcoal.
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Chaptini, Edmond, Elie Khoury, Vittorio Cacciafesta, and Nada Naaman. "Effect of Intraoral Aging on Debris Accumulation and Friction of First Molar Tubes." Journal of Contemporary Dental Practice 17, no. 11 (2016): 914–19. http://dx.doi.org/10.5005/jp-journals-10024-1953.
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ABSTRACT Aim The aim of this article was to evaluate the impact of intraoral aging and site specificity on debris accumulation and friction in molar tubes after intraoral use. Materials and methods A total of 80 intraorally used first molar convertible tubes were provided by 20 orthodontic adolescent patients after 6 months of treatment. The specimens were divided into eight groups (n = 10) according to the mouth quadrant and the type of examination [four groups of ten tubes for scanning electron microscope (SEM) and four groups of ten tubes for friction test]. Scanning electron microscope examination was performed after opening the convertible caps and friction test was executed using a 0.019” × 0.025” stainless steel wire, which was inserted in the tubes belonging to each group. The Mann. Whitney test, analysis of variance (ANOVA), and Bonferroni tests were performed for statistical analysis at 0.01 level of significance. Results There was a significant increase in the amount of debris and frictional force after 6 months of intraoral exposure (p < 0.0001). Debris scores were higher (10% increase) on the upper tubes when compared with the lower ones, with no statistical difference. Mean frictional force ranged from 0.22 to 0.26 N according to the mouth quadrant, but the difference between groups was also not significant. Conclusion After 6 months of intraoral exposure, there was a significant increase in the amount of debris in the first molar tube slots, leading to significantly higher frictional forces during sliding mechanics. The influence of site specificity on the amount of debris and on frictional forces of the first molar tubes could not be demonstrated. Clinical significance Molar tubes should be cleaned, before and during sliding mechanics, in order to minimize friction. How to cite this article Chaptini E, Khoury E, Cacciafesta V, Naaman N. Effect of Intraoral Aging on Debris Accumulation and Friction of First Molar Tubes. J Contemp Dent Pract 2016;17(11):914-919.
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Brown, Shannon E., Steve Sargent, and Claudia Wagner-Riddle. "Evaluation of a lower-powered analyzer and sampling system for eddy-covariance measurements of nitrous oxide fluxes." Atmospheric Measurement Techniques 11, no. 3 (March 22, 2018): 1583–97. http://dx.doi.org/10.5194/amt-11-1583-2018.
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Abstract. Nitrous oxide (N2O) fluxes measured using the eddy-covariance method capture the spatial and temporal heterogeneity of N2O emissions. Most closed-path trace-gas analyzers for eddy-covariance measurements have large-volume, multi-pass absorption cells that necessitate high flow rates for ample frequency response, thus requiring high-power sample pumps. Other sampling system components, including rain caps, filters, dryers, and tubing, can also degrade system frequency response. This field trial tested the performance of a closed-path eddy-covariance system for N2O flux measurements with improvements to use less power while maintaining the frequency response. The new system consists of a thermoelectrically cooled tunable diode laser absorption spectrometer configured to measure both N2O and carbon dioxide (CO2). The system features a relatively small, single-pass sample cell (200 mL) that provides good frequency response with a lower-powered pump ( ∼ 250 W). A new filterless intake removes particulates from the sample air stream with no additional mixing volume that could degrade frequency response. A single-tube dryer removes water vapour from the sample to avoid the need for density or spectroscopic corrections, while maintaining frequency response. This eddy-covariance system was collocated with a previous tunable diode laser absorption spectrometer model to compare N2O and CO2 flux measurements for two full growing seasons (May 2015 to October 2016) in a fertilized cornfield in Southern Ontario, Canada. Both spectrometers were placed outdoors at the base of the sampling tower, demonstrating ruggedness for a range of environmental conditions (minimum to maximum daily temperature range: −26.1 to 31.6 °C). The new system rarely required maintenance. An in situ frequency-response test demonstrated that the cutoff frequency of the new system was better than the old system (3.5 Hz compared to 2.30 Hz) and similar to that of a closed-path CO2 eddy-covariance system (4.05 Hz), using shorter tubing and no dryer, that was also collocated at the site. Values of the N2O fluxes were similar between the two spectrometer systems (slope = 1.01, r2 = 0.96); CO2 fluxes as measured by the short-tubed eddy-covariance system and the two spectrometer systems correlated well (slope = 1.03, r2 = 0.998). The new lower-powered tunable diode laser absorption spectrometer configuration with the filterless intake and single-tube dryer showed promise for deployment in remote areas.
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Widayat, Mochammad Faiq Yumna, Muhammad Hilmazar, Hantoro satriadi, and Aji Prasetyaningrum. "Processing of Used Beveraged Waste for Production of Hydroge Gas with Electrolysis Process Using NaOH Catalyst." E3S Web of Conferences 202 (2020): 08001. http://dx.doi.org/10.1051/e3sconf/202020208001.
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The production of hydrogen gas as an alternative fuel cell which is a renewable energy, is now in great demand by utilizing waste aluminum beverage cans and added water using NaOH catalyst by electrolysis process. The research method will be carried out by inserting 1 gram of aluminum pieces into a tube and 300 ml of distilled water followed by a NaOH catalyst. Both faucets are opened to release air during the filling process. The faucet is closed when the height of the solution in both tubes is the same. Then turn on the DC flow, then adjust the voltage according to the variable. The filling period is recorded until the specified reaction time. The results of the gas volume obtained are recorded, and the hydrogen obtained is determined by the flame test. From the research it can be concluded that the hydrogen gas produced from the reaction can be identified by means of a flame test. The characteristics of hydrogen gas appear in flames which tend to disappear in the air. At Al 5 gr Weight : 5 M NaOH concentration is the largest volume of hydrogen. The reaction time of 150 minutes will produce a lot of hydrogen gas. The largest volume of hydrogen gas lies at a voltage of 20 volts.
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Krylov, V. A., and R. G. Mosyagin. "Microextraction flotamicroextraction flotation concentration and determination of chloroacetic acids in watertion concentration and determination of chloroacetic acids in water." Аналитика и контроль 25, no. 2 (2021): 134–39. http://dx.doi.org/10.15826/analitika.2021.25.2.002.
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The flotation-assisted liquid-liquid microextraction method of mono-, di -, and trichloroacetic acids (CAAs) has been developed. Methyl tert-butyl ether (MTBE) was used as an extractant. The emulsification was performed by the ultrasonic irradiation. The microextraction procedure was carried out in a 27 ml special tube. It was equipped with the capillaries for sampling the extract and an air outlet. A salting-out additive (Na2SO4) was used to reduce the solubility of MTBE in water and to increase the extraction efficiency of CAAs. The air passage through the emulsion of the extractant was carried out using the eight-channel capillary bubbler. The organic matrix replacement was applied for ion chromatographic determination of CAAs with the conductivity detection. Current study showed the advantages of the flotation-assisted demulsification over the centrifugal one. The concentration factors of chlorinated acetic acids were 2-3 times higher. The detection limits of CAAs in water were reduced to (5·10-4 - 4·10-3 mg/l). The extraction time was reduced by more than three times. The trueness of the determination of HUC impurities was confirmed by the addition method. The statistical insignificance of the systematic error in comparison with the random error was shown. The developed method of preconcentration in combination with ion chromatography made it possible to determine the concentrations of CAAs 40-1250 times lower than the normalized SanPiN and WHO. This allowed conducting a highly sensitive determination of CAAs in water long before the onset of the critical ecological state.
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Takano, Atsushi, Ryuta Kitamura, Takuma Masai, and Sayaka Nishino. "Development of pre-molded internal thread on composite tubes." Composites and Advanced Materials 30 (January 1, 2021): 263498332110007. http://dx.doi.org/10.1177/26349833211000756.
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Premolded internal threads on composite tubes were developed. The composite tubes with threads on both ends were made using a mandrel with a male thread. The threads can be applied to struts with adjustable end fits and composite pressure vessels with threaded caps that enable disassembly for inspection and repair. Carbon fiber-reinforced plastic (CFRP) prepregs were laid up on a mandrel, wrapped with shrink tape, and cured in an oven. The threads were built-in, without using machine cutting, and the fibers on the thread were continuous through the thread and tubes for high strength. The thread was alternately rounded, convex, and concave in shape to enable CFRP prepregs to be laid up. Two types of specimen were made and tested. The layup sequence of specimen A was [0/h/90/h/0/h(1/2)]s, and that of specimen B was [0/h/90/h/90/h/0/h/90/h/90/h/90/h/90/h/0/h/90/90/0], where “h” denotes a helical layer along the concave part of the threads. The relation between load and strain is nonlinear because of the rounded shape of the threads; however, a simple and closed form analytical model was able to predict the strength of the threads and design of the threads. The model was compared with the experimental results. In addition, an application of threads for the pressure vessel of the hybrid rocket motor is also reported. The combustion test proceeded without failure. Visual inspection after the test indicated that the threads and tubes were not damaged, and thus, they can be applied to high-pressure and high-temperature rocket motors.
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Mirwan, Hamida B., and Peter G. Kevan. "Social Learning in Bumblebees (Bombus impatiens): Worker Bumblebees Learn to Manipulate and Forage at Artificial Flowers by Observation and Communication within the Colony." Psyche: A Journal of Entomology 2013 (2013): 1–8. http://dx.doi.org/10.1155/2013/768108.
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Social learning occurs when one individual learns from another, mainly conspecific, often by observation, imitation, or communication. Using artificial flowers, we studied social learning by allowing test bumblebees to (a) see dead bumblebees arranged in foraging positions or (b) watch live bumblebees actually foraging or (c) communicate with nestmates within their colony without having seen foraging. Artificial flowers made from 1.5 mL microcentrifuge tubes with closed caps were inserted through the centres of blue 7 cm plastic discs as optical signals through which the bees could not forage. The reinforcer reward syrup was accessible only through holes in the sides of the tubes beneath the blue discs. Two colonies (A and B) were used in tandem along with control (C and D) colonies. No bee that was not exposed (i.e., from the control colonies (C and D)) to social learning discovered the access holes. Inside colony B, we imprisoned a group of bees that were prevented from seeing or watching. Bees that saw dead bumblebees in foraging positions, those that watched nest-mates foraging, and those that had only in-hive communication with successful foragers all foraged successfully. The means of in-hive communication are not understood and warrant intense investigation.
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Al-Addous, Mohammad, Motasem N. Saidan, Mathhar Bdour, and Mohammad Alnaief. "Evaluation of Biogas Production from the Co-Digestion of Municipal Food Waste and Wastewater Sludge at Refugee Camps Using an Automated Methane Potential Test System." Energies 12, no. 1 (December 22, 2018): 32. http://dx.doi.org/10.3390/en12010032.
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The potential benefits of the application of a circular economy—converting biomass at Za'atari Syrian refugee camps into energy—was investigated in this study. Representative organic waste and sludge samples were collected from the camp, mixed in different ratios, and analyzed in triplicate for potential biogas yield. Numerous calorific tests were also carried out. The tangential benefit of the co-digestion that was noticed was that it lowered the value of the total solid content in the mixture to the recommended values for wet digestion without the need for freshwater. To test the potential methane production, the automated methane potential test system (AMPTS) and the graduated tubes in the temperature-controlled climate room GB21 were utilized. Also, calorific values were determined for the organic waste and sludge on both a dry and a wet basis. The maximum biogas production from 100% organic waste and 100% sludge using AMPTS was 153 m3 ton-1 and 5.6 m3 ton-1, respectively. Methane yield reached its maximum at a Vs sub/ Vs inoculum range of 0.25–0.3. In contrast, the methane yield decreased when the Vs sub/ Vs inoculum exceeded 0.46. The optimum ratio of mixing of municipal food waste to sludge must be carefully selected to satisfy the demands of an energy production pilot plant and avoid the environmental issues associated with the sludge amount at wastewater treatment plants (WWTPs). A possible ratio to start with is 60–80% organic waste, which can produce 21–65 m3· biogas ton-1 fresh matter (FM). The co-digestion of organic waste and sludge can generate 38 Nm3/day of methane, which, in theory, can generate about 4 MW in remote refugee camps.
Dissertations / Theses on the topic "Test tube caps"
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Bisca, Jacqueline Muniz. "Prevalência dos tipos sanguíneos A, B e AB em felinos selvagens neotropicais nativos do Brasil." Botucatu, 2017. http://hdl.handle.net/11449/151017.
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Orientador: Carlos Roberto TeixeiraResumo: Os felinos selvagens neotropicais habitam as Américas do Sul e Central, porém apenas oito espécies são nativas do Brasil. Foi reportado em felinos selvagens o mesmo sistema AB sanguíneo de felinos domésticos, composto por três tipos, A, B e o mais raro AB. O objetivo deste trabalho foi realizar tipagem sanguínea nas espécies de felídeos neotropicais brasileiras através do teste em cartão e teste de hemaglutinação em tubo de ensaio. Comparar o uso destas técnicas e descrever a prevalência dos tipos sanguíneos A, B e AB nestas espécies. Foram coletadas 42 amostras de seis diferentes espécies de felinos selvagens neotropicais, sendo dez Leopardus tigrinus, sete Leopardus weidii, oito Leopardus pardalis, dois Puma yagouaroundi, quatro Puma concolor e 11 Panthera onca. Todos os animais pertencentes ao gênero Panthera e Leopardus foram positivos para o tipo sanguíneo A em ambos os testes realizados. Já os animais pertencentes ao gênero Puma, foram positivos para o tipo B. Não houve problemas para tipagem através do método em cartão, sugerindo uma boa aplicabilidade na tipagem sanguínea em felídeos.
Abstract: Neotropical wild felids habit South and Central America, but only eight species are native to Brazil. The same AB blood system of domestic cats has been reported in wild cats, consisting of three types, A, B and the rarest AB. The objective of this work was to perform blood typing in Brazilian neotropical wild cats species through the card test and hemagglutination test in a test tube. Compare the use of these techniques and to describe the prevalence of blood types A, B and AB in these species. A total of 42 samples of six different Neotropical wild cat species were collected: ten Leopardus tigrinus, seven Leopardus weidii, eight Leopardus pardalis, two Puma yagouaroundi, four Puma concolor and 11 Panthera onca. All animals belonging to the genus Panthera and Leopardus were positive for blood type A in both tests. However, the animals belonging to the Puma genus were positive for type B. There were no problems for typing through the cardboard method, suggesting a good applicability in feline blood typing.
Mestre
Books on the topic "Test tube caps"
Book chapters on the topic "Test tube caps"
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Fox, Dov. "Missing Protections." In Birth Rights and Wrongs, 25–36. Oxford University Press, 2019. http://dx.doi.org/10.1093/oso/9780190675721.003.0003.
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No governmental agency or authority seriously polices reproductive negligence. The best practices set forth by industry organizations are completely voluntary and routinely ignored, and there isn’t even any reliable or comprehensive system to track the wrongful thwarting of family planning. The breakneck pace of reproductive advances isn’t the only reason that test tubes and tube ties have eluded meaningful oversight: Four factors explain this regulatory vacuum. First, many are wary of ceding the state control on any matter involving procreation—red tape would raise prices on valuable services, making it harder for poor people to pay for them. Second is the political economy of reproductive technology in the United States: The free-market origins of infertility treatment let it develop unimpeded by government oversight, in the private sphere of for-profit clinics that function less as medical practices than trade businesses. A third factor that cuts against regulation is its murky electoral implications, even in reliably red or blue districts—fear of fracturing their political bases leads prudent officials to avoid wading into the morass. Fourth and finally is the limited public outcry to address reproductive negligence. Besides, steep costs and selective treatment coverage leaves many patients unable even to fund a legal challenge if things go wrong. State legislatures place damage caps and other barriers in the way of bringing suit. And trials can be a spectacle for plaintiffs wary of exposing personal matters to the public glare of open court.
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Parrington, John. "Introduction." In Redesigning Life, 1–6. Oxford University Press, 2020. http://dx.doi.org/10.1093/oso/9780198766834.003.0001.
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We are in the middle of a scientific revolution in the biological sciences. In the 1970s scientists discovered ways to cut and paste DNA in a test tube, and then introduce gene ‘constructs’ into first bacteria and then more complex organisms such as mice. This made it possible to, for instance, produce human insulin artificially in bacteria, but also to create genetically modified mice for medical research. But such genetic engineering methods were expensive, time-consuming, and limited to only certain organisms. In contrast in recent years, new ‘genome editing’ approaches, particularly one called CRISPR/Cas, now makes it possible for the first time to precisely edit the genome of living cells from practically any species. Genome editing looks set to revolutionise medical research, clinical medicine, and agriculture, as the rest of this book will explain. But this is only one of the new technologies discussed In Redesigning Life. Others include optogenetics, which makes it possible to activate nerve cells in the brain using light, ‘organoids’, which are created from human stem cells, and have similarities to human organs like the kidney, intestines, heart, and even brain, and synthetic biology, which seeks to create artificial bacteria and yeast chromosomes from scratch and even reconfigure the genetic code. All of these technologies have great potential for improving human society, but they also raise many ethical and socio-political issues and questions about ways they might be misused, which will be explored in this book.
Conference papers on the topic "Test tube caps"
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Pesetti, Alessio, Alessandro Del Nevo, and Nicola Forgione. "Experimental Investigation of Spiral Tubes Steam Generator Rupture Scenarios in LIFUS5/Mod2 Facility for ELFR." In 2016 24th International Conference on Nuclear Engineering. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/icone24-60715.
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In the framework of the EC FP7 LEADER project, an experimental campaign was performed in the LIFUS5/Mod2 facility, at ENEA CR Brasimone, for investigating the postulated Steam Generator Tube Rupture (SGTR) event in a relevant configuration for the spiral tube Steam Generator (SG) of the European Lead Fast Reactor (ELFR). Two tests are analysed. The LIFUS5/Mod2 facility implemented a test section composed by 188 tubes, vertically disposed with triangular pitch, in a shell closed by top and bottom flanges and having a perforated cylindrical wall. The central tube injected water at about 180 bar and 270°C, at middle height of the tube bundle, in the reaction tank partially filled by Lead-Bismuth Eutectic alloy (LBE) at 400°C with an argon cover gas at about 2 bar. It was connected to a 2 m3 dump tank, due to the high injection pressure. In the reaction tank fast instrumentation was set: 6 fast Pressure Transducers (PTs) acquiring data at 10 kHz for precisely characterize the first injection peaks; 70 low constant time Thermocouples (TCs) to understand the vapour evolution path; and 13 strain gages (SGGs) to measure the strain of the bundle and main vessel. The first test analysed showed a first pressure peak of about 25 bar, due to pressure wave propagation at the cap rupture instant. It did not appear in the second test as consequence of a leakage from the cap before the complete rupture. The following pressurization caused by the entering of water into the reaction vessel was of an analogues magnitude for both the tests (about 30 bar). The water/LBE interaction lower temperature was reached on the inner ranks of tubes, about 160°C. The outer rank was cooled down to 340°C. The strain gage measurements showed a decreasing deformation on the tubes toward the outer positions. No ruptures were observed on tubes surrounding the injector. The amount of LBE transported into the dump tank was strongly dependent on the LBE level in the reaction tank at the start of the tests.
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Pesetti, Alessio, Alessandro Del Nevo, Andrea Neri, Stefano Cati, Valerio Sermenghi, Massimo Valdiserri, Daniel Giannotti, Mariano Tarantino, and Nicola Forgione. "Experimental Investigation in LIFUS5/Mod2 Facility of Spiral-Tube Steam Generator Rupture Scenarios for ELFR." In 2017 25th International Conference on Nuclear Engineering. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/icone25-67420.
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In the framework of the European Commission LEADER project, an experimental campaign of seven tests was performed in the LIFUS5/Mod2 facility, at ENEA CR Brasimone, for investigating the postulated Steam Generator Tube Rupture (SGTR) event in a relevant configuration for the Spiral-Tube Steam Generator (STSG) of the European Lead Fast Reactor (ELFR). The LIFUS5/Mod2 facility is composed by a water tank of 15 L injecting subcooled water up to 200 bar into the reaction tank of 100 L (420 mm of diameter), which is connected by a 3 inch pipe to the dump tank of 2 m3. A dedicated test section was designed, assembled and implemented in the reaction tank. It is composed by 188 tubes, vertically disposed with triangular pitch inside a cylindrical support. This tube bundle is representative of a portion of the STSG of ELFR. The cylindrical support is closed at the lower and upper end by two tube plates and has a perforated lateral shell (300 mm of diameter and 400 mm high). The reaction tank is filled by Lead-Bismuth Eutectic alloy (LBE) at 400°C up to the top tube plate, with an argon cover gas at about 2 bar. The water is injected at about 180 bar and 270°C through the central tube, at middle height of the bundle. The water-LBE interaction is characterised by high quality data acquisition system: 6 fast Pressure Transducers (PTs) working at 10 kHz for precisely characterize the first narrow injection peaks, 70 low constant time Thermocouples (TCs) to understand the vapour evolution path and 13 strain gages (SGGs) for measuring the strain of the bundle and main vessel. The overall LEADER experimental campaign is constituted by seven tests, divided in three series (B1, B2 and B3), characterized by different injection orifice diameters of 4, 8.9 and 12.6 mm, respectively. This paper presents the experimental results of the first two tests of series B2 (B2.1 and B2.2) having 8.9 mm of injection orifice. The first test analysed showed a first narrow pressure peak of about 32 bar, some milliseconds after the cap rupture instant. The following pressurization due to the evaporation of water entered into the reaction vessel was of an analogues magnitude for both the tests (about 50 bar) and lasted some tenths of second. The water/LBE interaction lower temperature was reached on the inner ranks of tubes, about 150°C. The outer rank was cooled down to about 300°C. The strain gage measurements showed a decreasing deformation on the tubes toward the outer positions. No ruptures were observed on tubes surrounding the injector. The amount of LBE transported into the dump tank was strongly dependent on the LBE level in the reaction tank at the start of the tests and about 200 kg.
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McGinley, John. "Electromagnetic Pulse Technology as a Means of Joining Generation IV Cladding Materials." In 17th International Conference on Nuclear Engineering. ASMEDC, 2009. http://dx.doi.org/10.1115/icone17-75630.
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The Institute for Transuranium Elements (ITU) has conducted investigations into the possibility of using Electromagnetic Pulse Technology (EMPT) in joining PM 2000 ODS and T91 ferritic-martensitic steels, using samples fabricated to simulate tube and end caps. The investigations are primarily directed towards the joining of cladding tubes to enable fuel pins to be produced in its laboratories. A suitable field former was fabricated and the tests coordinated and financed by ITU were carried out initially by a specialist EMPT company. To date, joints with a helium leak rate of leak in the range 10−8 mBar.litres.s−1 have been achieved. Further refinement of the parameters is now being done in order to improve the weld quality and achieve the target leak-rate of 1.0 × 10−9 mBar.litres.s−1.
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Shuai, Jian, and Wenping Bu. "Full Scale Experimental Analysis of Stress State in Welding Repairs of Drilled Pipelines." In 2006 International Pipeline Conference. ASMEDC, 2006. http://dx.doi.org/10.1115/ipc2006-10225.
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Recently, drilling holes in petroleum transmission pipelines is becoming of major concern for pipeline companies. These drilled pipelines must be repaired through welding ways. There are two ways to repair these pipelines in fields. One is welding a short tube with a cap. Another is welding a patch. In this paper, full scale experiments were conducted to assess the stresses state and the loading capability of the repaired pipelines. The φ711×10 pipelines repaired by welding a tube cap or a patch were pressured to burst failure. Strain gages have been used extensively to monitor stress state in full scale pipeline tests. It was showed that welding a tube cap or a patch resulted in the non-uniform stresses distribution and the stress concentration in the extent. These two kinds of the repaired pipeline has almost the similar yield limit pressure which are approximately equal to 85% of that of pipelines that were not damaged. Patching repair has more restriction to the deformation around a hole than tube capping repair, therefore it may have a little better loading capacity than tube capping repair. The burst pressures in these tests are close to that of pipeline which has not been damaged, whereas the location of burst failure is far from where a short tube or a patch is welded. The burst is a ductile fracture by maximum shear stress.
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Seo, Bum-Kyoung, Sung-Kyun Kim, Kune-Woo Lee, Jin-Ho Park, Nan-Ju Lim, and Myeong-Jin Han. "The Measurement of Radioactive Surface Contamination Using an Inorganic Fluor-Impregnated Membrane." In ASME 2003 9th International Conference on Radioactive Waste Management and Environmental Remediation. ASMEDC, 2003. http://dx.doi.org/10.1115/icem2003-4595.
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Solid scintillation proximity membranes were prepared for measuring surface in laboratories contaminated by the all types of radionuclides, such as H-3, C-14, and Cs-137 etc. Polysulfone scintillation proximity membranes were prepared by impregnating Cerium Activated Yttrium Silicate (CAYS),an inorganic fluor, in a membrane structure. The inorganic fluor-impregnated membranes were applied to detect the radioactive surface contamination directly without the aid of a scintillation cocktail. The preparation of membranes was divided into two processes. A supporting polymer film was made of casting solution consisting of polysulfone and solvent, their cast film being solidified by vacuum evaporation. CAYS-dispersed polymer solutions were cast over the first, solidified polymer films and coagulated either by evaporating solvent in the solution with non-solvent in a coagulation bath. The prepared membranes had two distinguished, but tightly attached, double layers: one is the supporting layer of dense polymer film and the other results revealed that the prepared membranes were eficient to monitor radioactive contamination with reliable counting ability. For enhancement of pick-up and measurement efficiency, the membrane was prepared with the condition of different membrane solidification. The scintillation produced by interaction with radiation and CAYS was measured with photomultiplier tube. The test results of the cocktail-free wipe test showed that the prepared membranes were efficient to monitor radionuclide-contaminated areas with the good counting ability as well as with the decrease of overall production of radioactive waste.
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Raji, Hauwa, and Jamie Fletcher Woods. "Effect of Weld Geometry on the Fatigue Behaviour of Umbilical Super Duplex Stainless Steel Tubes." In ASME 2017 36th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/omae2017-61411.
Full textAbstract:
The fatigue behavior of welded components is complicated by many factors intrinsic to the nature of welded joints. The mechanical properties of the material, the welding process and position, the type and geometry of the weld and the residual stress distribution across the weld are a few factors affecting fatigue behavior. Published studies [1, 2] have shown that weld geometry is significantly important in determining the fatigue strength of the weld. For a given weld geometry, the fatigue strength is determined by the severity of the stress concentration at the weld toe or at weld defects and by the soundness of the weld metal. The effect of external weld geometry profile on the fatigue behavior of welded small bore super duplex umbilical steel tubes is investigated. Root cause analysis consisting of fractography, metallography and weld profile measurement is carried out on pairs of fatigue failure samples which were tested at the same stress range but failed at significantly different number of cycles. The samples are selected from Technip Umbilicals Ltd (TU) fatigue database. Following the failure analysis, weld geometric profile measurements are performed on fatigue test samples that were prepared for testing. The weld profile was measured in terms of the external weld cap height, weld width and external linear misalignment. Axial fatigue tests are carried out on these samples which are pre-strained before test to simulate the plastic bending cycles typically experienced during the manufacturing and installation processes prior to operational service. The fatigue tests results are interrogated together with the measured geometric data to identify trends and anomalies. Key weld geometric fatigue performance criteria are subsequently identified. For the welded super duplex stainless steel (SDSS) tubes studied, the height of the weld and the weld toe angle provided the best correlation with fatigue life — shorter lives were obtained from specimens with the highest weld aspect ratio (weld height to width) and lowest weld toe angle.
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An, Xiaoxue, Alan Dobson, and Chun Yip Chan. "Influence of Porosity on the Integrity Properties of Butt Welded Super Duplex Stainless Steel Umbilical Tube." In ASME 2015 34th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/omae2015-42032.
Full textAbstract:
Super Duplex Stainless Steel (SDSS) tube is the main component in steel tube umbilicals for the transportation of hydraulic fluids and chemicals, or gas injection into the subsea well. The umbilical tube is made from seamless tube joined together by girth weld. Therefore, porosity is one of the main weld defects that could be discovered within the welds, and these defects can have significant impact on the execution of the whole project, in term of both schedule and cost. This paper reviews the design codes and standards relating to the porosity acceptance criteria, and discusses the recent investigation on the influences of porosity (number, size and location) to the stress distribution within the weld. The study was performed using both FEA and practical fatigue test. The results demonstrated that the distance of the pores to the weld surface is a critical parameter to the increase and localisation of stress as the pore starts to interact with the weld root or cap. In addition, significant pore stress interaction has been observed when a bending moment is introduced to the weld. The study has demonstrated that the current porosity acceptance criteria applied to umbilical manufacture in the subsea industry are typically conservative and can be modified.
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Rouwenhorst, Driek, Robert Widhopf-Fenk, Jakob Hermann, Matthias Häringer, Julius Becker, Jürgen Gerhard, and Julian Niedermeier. "Part-Load Limit Reduction of a Frame 9E Using a Precursor for Combustion Dynamics." In ASME Turbo Expo 2018: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/gt2018-75468.
Full textAbstract:
In a test campaign to lower the minimum part-load of a combined cycle plant, a series of turndown tests on two GE Frame 9E gas turbines with DLN1 combustor technology were carried out under premix operation by Stadtwerke München (SWM). It has been found that the load can be reduced significantly compared to the conventional turndown ratio, before either CO emissions or combustion dynamics form the limiting factor of the turndown test. To exploit this potential safely and operate the gas turbines close to these physical limits, emissions and combustion dynamics must be monitored online. The azimuthal thermoacoustic mode that is observed in the can-annular machines is monitored with the IfTA PreCursor, based on the online determination of the modal decay rate. For this method, the acoustic pressure is measured at the cans around the gas turbine circumference to observe the azimuthal acoustic propagation that is enabled by the cross-firing tubes between the cans. Using this strategy to monitor CO emissions and thermoacoustic stability in real-time, a reduction of the minimal part-load limit by approximately 20% is achieved for the considered gas turbines. In must-run situations without demand for electricity generation, the operating costs can be directly reduced by the fuel savings. As an additional benefit, SWM can offer a broader power reserve for grid stabilization on the energy market. This monitoring strategy has been fully implemented in the control system and first experiences of the extended part-load limit are currently being gathered.
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Geer, Ryan, and Suyi Li. "Examining the Coiling Motion of Soft Actuators Reinforced With Tilted Helix Fibers." In ASME 2018 Conference on Smart Materials, Adaptive Structures and Intelligent Systems. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/smasis2018-8038.
Full textAbstract:
This study aims to examine the coiling and uncoiling motion of a soft pneumatic actuator reinforced with tilted helix fibers. Coiling motion can be quite useful for robotic manipulation and locomotion purposes. This research proposes and investigates a novel actuator that is inspired and derived from the unique cell wall architecture in the seed appendage of Stork’s Bill plant (Erodium Gruinum). These plant cells are reinforced by cellulose fibers distributed in a tilted helix pattern — helixes that are tilted at a certain angle with respect to the longitudinal axis of the cell. As a result, the seed appendage can coil and uncoil via a combination of twisting and bending. This paper discusses the design, fabrication, and testing of a soft actuator that can mimic this sophisticated motion. This actuator consists of Kevlar fiber thread wrapped around a silicon rubber body that has the shape of a tube. The tube will be capped at both ends so that it can be pressurized internally to induce motion. Once the design parameter has been chosen, the soft actuator are fabricated by 1) designing and 3D printing molds, 2) tube casting and fiber wrapping, and 3) creating the end caps for pressure sealing. Carefully executing these fabrication steps is essential because any errors could give undesired deformation. Several soft actuators prototypes are fabricated based on different design choices regarding the actuator radius, tube wall thickness, and the number of tilted helix fibers (aka. fiber coverage). Proof-of-concept tests show that these actuator prototypes can indeed exhibit a combined twisting and bending under internal pressurization: all are the necessary receipts to achieve the coiling and uncoiling motion. Result of this paper can pave the way for a new family of soft actuators capable of unprecedented and sophisticated actuation motions, which are particularly appealing for soft robot application.
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Xiao-Chun, Hou, Siao Tong-Fu, and Zhong Jian-Ping. "Investigation and Experiment on a Short Dump-Diffuser of the Combustor." In ASME 1985 Beijing International Gas Turbine Symposium and Exposition. American Society of Mechanical Engineers, 1985. http://dx.doi.org/10.1115/85-igt-28.
Full textAbstract:
This paper is intended to introduce optimal geometrical parameter matching obtained by using water flow simulation on the box-type specimen and blasting tests on the sector-type specimen for the short dump-diffuser of an annular combustion chamber, and some special problems occurring in practice, such as, the effects of the factors — the head of flame tube, inlet cap, inlet support strut, splitting flow cone, air drawn from the wall surface and inlet velocity profiles on diffuser performance and its flow status, the obtained results provide the foundation for its practical application.