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Sample records for fushoku suimo koban

  1. Consideration on fatigue strength of corroded steel plates; Fushoku suimo koban no hiro kyodo ni kansuru ichikosatsu

    Energy Technology Data Exchange (ETDEWEB)

    Iwata, M.; Yajima, H.; Yamamoto, M.; Saito, T. [Hiroshima University, Hiroshima (Japan). Faculty of Engineering

    1996-10-01

    Discussions were given on fatigue strength of corroded steel plates taken from a hull of a ship seventeen years old after construction. The steel plates have had their original thickness of 13 mm reduced to 5.3 to 8.3 mm. After having been cut by a machine, the steel plates were used for tests as ground plates after going through grinding and as corroded plates with rust remaining on them. The fatigue test was performed in artificially made sea water at a temperature of 25{degree}C and in air with axial power pulsating tensile load and at iterative loading velocities of 3 to 5 Hz. The corroded material test verified that corrosion pits exist innumerably on the test piece surface and fatigue cracks have been developed and grown from bottoms of the pits. The stress concentration coefficient of the corrosion pits was about 1.9. Good agreement with the test result was found in the S-N chart in which the number of iteration of fracture was regarded as the number of iteratively generated cracks, and notch coefficient was estimated as 1.9. These results proved that the fatigue strength assessing method for virgin materials can be applied also to steel plates which have been exposed to corrosive environment for extended periods of time. 5 refs., 7 figs., 1 tab.

  2. 17-18世纪荷兰人从日本运出小判分析%Koban Trade between Japan and Duth in 17-18th Century

    Institute of Scientific and Technical Information of China (English)

    张兰星

    2015-01-01

    16世纪欧洲人抵日经商,发现这里盛产金银,但在日本锁国前(1640年),欧洲人只能运走白银,日本方面不但禁止黄金被运出,还让欧洲人运来黄金。锁国后,荷兰人成为唯一留在日本的西方人,幕府为了缓解日本白银的过多外流,遂允许荷兰人运走日本小判(金币)。以金代银是日本外贸政策的重要变化,预示着日兰贸易即将走向衰落。持续近百年的小判贸易,是日兰商贸交流的重要内容,亦是世界海洋贸易史及世界经济发展史的组成部分。%From the 16th century, the Europeans began to trade with Japan. Before Japan’ s seclu⁃sion in 1640, although Japan at that time was rich in gold and silver, it allowed the silver export to Euro⁃peans only. Gold was only imported from Europe as gold export to Europe was prohibited. Nevertheless, after Japan’ s seclusion in 1640, the Dutch was the only European country that was allowed to have trade with Japan. In order to avoid the excessive export of silver, Shogunate allowed the export of Koban, namely, gold, to Dutch. The export of gold instead of silver is a milestone to show the declining of trade between Japan and the Netherland. Koban trade is not only a major part in the trade between those two countries, but also an integral part of the history of world marine trade and the history of world economic development.

  3. Effect of tannic acid on corrosion of mild steel in boiler system. Boiler kei deno nanko no fushoku ni taisuru tanninsan no fushoku yokusei koka

    Energy Technology Data Exchange (ETDEWEB)

    Shibata, Y.; Imahama, T.; Wake, T. (Japan Organo Co. Ltd., Tokyo (Japan)); Sekine, I.; Kawase, T.; Shiromoto, T.; Yuasa, M. (Science University of Tokyo, Tokyo (Japan). Facutly of Science and Technology)

    1992-08-15

    Tannic acid was studied as a corrosion inhibitor in boiler system from the view points of safety and economy. Hydrolytic tannin extracted from gallnut was used as tannic acid and gallic acid, hydrazine and sodium sulfite were used as the reference samples. A mild steel (JIS SS 400) was used for the test steel. The following test were made in the comparative experiments: the measurement of polarization curve of the mild steel by electrochemical method, and the analyses of surface change of mild steel by using a scanning tunnelling microscope and the X ray photoelectron spectrography, etc. Tannic acid exhibits the corrosion inhibiting effect identical to those of reference samples under alkaline condition. Tannic acid has the inhibiting effect even under high temperature and pressure condition and the maximum inhibition efficiency is 97%. Tannic acid exhibits the adsorption type inhibition under the neutral condition. Under alkaline condition, tannic acid inhibits corrosion of steel not only as an effective oxygen scavenger but also an effective passivating effect forming Fe[sub 3]O[sub 4]. Tannic acid is concluded as an effective oxygen inhibitor. 17 refs., 11 figs.

  4. Microbial corrosion in weld zone of stainless steel. Stainless ko yosetsubu no biseibutsu fushoku

    Energy Technology Data Exchange (ETDEWEB)

    Sasaki, E. (National Chemical Laboratory for Industry, Tsukuba (Japan)); Nishimura, M. (Mitsubishi Kakoki Kaisha, Ltd., Tokyo (Japan))

    1992-10-15

    Microbial corrosion may happen wherever water is treated in many kinds of practical metal except titan, such as common steel, copper alloy, stainless steel, and high-nickel alloy. Although microbes causing microbial corrosion are not limited to specified microbes, specially affecting microbes are iron bacteria, iron-oxidizing bacteria, and sulfate-reducing bacteria. mechanism in these microbial corrosion, which is fundamentally caused through formation of oxygen concentration cells and production of metabolites, is complex and different by each microbe. In the case of stainless steel, the corrosion is located mainly in weld zones or heat affected zones, the shape of corrosion is like a pot, and the pattern is a type of pitting corrosion. Microbes are apt to adhere to the surface near weld zones, then oxygen becomes consequently insufficient beneath the surface, where the self-mending capacity of passive films is deprived, resulting in occurrence of pitting corrosion. For protection of microbial corrosion, it is essential to control water so that habitation of microbes is not formed. 9 refs., 3 figs.

  5. Production technology for actual fields in severe corrosive environments; Fushoku kankyo jitsu fuirudo jisshoka gijutsu

    Energy Technology Data Exchange (ETDEWEB)

    Takai, T.; Kaneda, E.; Shoda, S.; Tochikawa, T. [Japan National Oil Corp., Tokyo (Japan)

    1998-10-30

    Joc has been developing the hardware and software, in corrosion and protection research project which has tree subthema as follows with collaborators. 1. From 1985 JNOC and JRCM have been developing the Coated TBG. Last year, we selected a gas well for the evaluation in Astrakhan Gas Field in Russia where production gas contains 25 % H{sub 2}S, and started the verification test of the corrosion resistance of the Coated TBG. 2. Two new coating technologies (Plasma sintering and YAG-laser cladding technology) are tried to apply for coating of well equipment. The former technology aims at improving erosion-resistance of drilling tools, for instance, blade stabilizer. The later aims to improve erosion-resistance and corrosion-resistance of production equipment which have complex curved surface or narrow sections. 3. JNOC and Nippon Steel have been developing the Material Selection Program for Tubing Strings. The prototype program has been produced, which includes some new items, galvanic corrosion effect in combination strings, corrosion properties of new material (modified 13Cr), reflection on the environments in actual well, and including the material cost. The influence of fluid velocity, WOR and dew point upon the corrosion-rate will be estimated. (author)

  6. Production technology for actual fields in severe corrosive environments; Fushoku kankyo jitsu field jisshoka gijutsu

    Energy Technology Data Exchange (ETDEWEB)

    Kaneda, H.; Ihara, K.; Wasada, N. [Tech. Research Center, Japan National Oil Corp., Tokyo (Japan)

    1995-11-10

    Tests and studies were started for the verification of the coated tubing developed using the element technology introduced in the special study `Production Technology in High-Temperature Corrosive Environments`, for the development of oil exploring equipment serviceable in corrosive environments, and for the development of programs for selecting materials for use in corrosive environments. In connection with verification tests, investigations were conducted into the operating fields of domestic oil exploring corporations and into technical literature relating to the deterioration of basic materials in their resistance to SSC, and basic data were accumulated. In the efforts to develop equipment, it was decided that drilling stabilizer blades be developed by plasma sintering, that information be collected concerning technologies relating to functionally gradient materials, and that technologies be developed for YAG-laser cladding of flange seal surfaces and elbow inner surfaces. As for the development of material selecting programs, various tests were conducted into the 13Cr steel and super 13Cr steel for their SSC, total corrosion, and local corrosion, their performance was evaluated, and the limit of their serviceability was determined by mathematical treatment. 7 figs., 3 tabs.

  7. Consideration on corrosion fatigue crack life assessment; Fushoku hiro kiretsu hassei jumyo hyoka ni kansuru ichikosatsu

    Energy Technology Data Exchange (ETDEWEB)

    Yajima, H.; Yamamoto, M.; Saito, T. [Hiroshima University, Hiroshima (Japan). Faculty of Engineering; Morita, K. [Mitsubishi Heavy Industries, Ltd., Tokyo (Japan)

    1996-10-01

    Discussions were given on corrosion fatigue crack life by using corrosion fatigue crack initiation test and analysis. The test used 13Cr-based stainless steel as a test material, and aquamarine at 60{degree}C as a corrosion environment. The fatigue test was performed under a tension loading condition with a stress ratio of 0.1 and an iterative velocity of 1.7 Hz by using a 10-tonf fatigue testing machine. In the corrosion fatigue crack initiation test, a pit has been generated on a boundary of an exposed part and a painted part for masking, hence direct observation was impossible on pit growth behavior. Therefore, an intrinsic crack model was introduced from pit dimensions as observed from a fracture face, and analysis was made on corrosion fatigue crack growth by using the linear fracture dynamics, wherein clarification was made on a phenomenon occurring after the crack growth passes the pit growth until the test piece is fractured. A proposal was made to define the time when fatigue crack initiates and grows from the bottom of a pit as a result of surpassing the growth of corrosion pit as the corrosion fatigue crack life. 4 refs., 7 figs., 1 tab.

  8. Degradation and cupric corrosion caused by corrosive sulfur in insulating oil; Zetsuen`yu no rekka to ryuka fushoku

    Energy Technology Data Exchange (ETDEWEB)

    Tsuchie, M.; Miyamoto, T. [Mitsubishi Electric Corp., Tokyo (Japan)

    1995-03-20

    As the voltages and capacities of transformers have been increased, a higher reliability of insulating oil has been demanded. Since the 1970s, sulfurization and streaming electrification of a copper product have attracted attention. In the 1970s, an insulating oil refining method was changed from sulfuric acid refining to hydrogenation refining. In the 1980s, an insulating oil to which benzotriazole (BTA) effective for suppression of streaming electrification is added came to be used. Although the degradation of an insulating oil and the sulfurization in the oil are different phenomena, it has been found out that copper takes part in both of these phenomena. This paper describes the examination of the effect of BTA on the oxidation degradation and sulfurization of insulating oil. The examination was made by using an oxidation degradation evaluation apparatus developed from the above-mentioned viewpoint. The results of the examination show that BTA is very effective in suppressing the oxidation degradation and sulfurization of insulating oil. 11 refs., 13 figs., 2 tabs.

  9. Required grades of hull steel plates in consideration of fracture toughness; Hakai jinsei wo koryoshita sentaiyo koban shiyo kubun ni kansuru ichikosatsu

    Energy Technology Data Exchange (ETDEWEB)

    Yajima, H.; Yamamoto, M.; Ogaki, Y. [Hiroshima University, Hiroshima (Japan). Faculty of Engineering

    1997-10-01

    This paper discusses the required grades of hull steel plates based on the steel ship rule of Nippon Kaiji Kyokai (NK). The minimum value of the allowable crack length in NK rule (critical safety crack length at 0degC just before brittle unstable crack causing fatal fracture) was estimated. In the case where the estimated crack tip exists in a matrix, the crack length was a minimum of 200-210mm, while nearly 60mm in a fusion line at high-heat-input welded joint. The allowable crack lengths estimated from a specified value in the NK rule were fairly different. The allowable crack length at 0degC was also estimated from the minimum value in V-notch Charpy impact test. The private proposal on the required grades of hull steel plates in consideration of fracture toughness was discussed. Thirty-five percent of crack lengths found in real ships is 100mm or less, however, cracks of 250-400mm long are frequently found suggesting the allowable crack length of 400mm. The required grade integrally considering required values and design conditions is demanded to secure the reliability of hull strength. 5 refs., 5 figs., 2 tabs.

  10. Temperature effect on corrosion fatigue strength of coated ship structural steel; Zosen`yoko tosozai no fushoku hiro kyodo ni okeru ondo no eikyo

    Energy Technology Data Exchange (ETDEWEB)

    Takanashi, M.; Fuji, A.; Kojima, M.; Kitagawa, M. [Ishikawajima-Harima Heavy Industries Co. Ltd., Tokyo (Japan); Kobayashi, Y. [Ship Research Inst., Tokyo (Japan); Kumakura, Y.

    1997-08-01

    The corrosion fatigue life was obtained using uncoated and tar epoxy resin specimens to clarify the temperature effect. The life curve for corrosion fatigue of machined and uncoated steel in the air and sea was obtained. The fatigue strength of uncoated steel largely decreases in the sea and breaks even in the nominal stress range of less than 1/2 of the fatigue limit in the air. The effect of temperature on the coated steel is represented by a corrosion coefficient. The steel coated at 25{degree}C is 1/1.03 to 1/1.13 at 40 to 60{degree}C. This showed that the fatigue strength decreases when the temperature exceeds 25{degree}C. However, it has not such tendency and significance that are represented quantitatively. There is a slight difference in the short-life area between the crack generation life and breaking life. However, the long-life area has no significance that influences the whole evaluation. In the long-life corrosion fatigue, the crack occurs from the corrosion pit due to the exposure below the coated film and progresses in the base material before the coated film is destroyed. The effect of the corrosion pit remarkably appears at a low-stress level. 14 refs., 14 figs., 4 tabs.

  11. Consideration on buckling and plastic breakdown strength characteristics of a steel plate with surface layers of ultra fine grain microstructure (SUF); Hyoso chosairyu koban no zakutsu sosei hokai kyodo tokusei ni kansuru ichikosatsu

    Energy Technology Data Exchange (ETDEWEB)

    Yamamoto, M.; Yao, T.; Yajima, H.; Miyamoto, H.; Morita, S. [Hiroshima University, Hiroshima (Japan). Faculty of Engineering; Ogihara, Y.; Ishikawa, T. [Nippon Steel Corp., Tokyo (Japan)

    1996-10-01

    Buckling and plastic breakdown strength characteristics of a structure fabricated by using new steel plates with surface layer made into ultra fine grain structure were analyzed and discussed by using a belt plate buckling and plasticity test and the finite element method. The tested steel plate has a thickness of 25 mm, and was fabricated for ocean vessel use, with surface layers on both sides of about 1/6 of the whole thickness having been made an ultra fine grain structure. As a result of a belt steel buckling and plasticity test on a steel plate with surface ratio of 29%, both of the initial yield stress and the buckling stress were found increased by about 4 to 10% as compared with a steel plate having surface ratio of 0%. An analysis by using the finite element method was made on square steel plates with a length of 80 cm, a width of 100 cm, and thicknesses of 12 mm and 24 mm. A result was obtained that, in the case of surface layer ratio of 33%, both of the initial yield stress and the maximum load withstanding force were higher by 5 to 16% than the case of surface ratio of 0%. Similar rise in strength was shown also in bend preventing plates which are basic constituting members of a vessel. 6 refs., 10 figs., 2 tabs.

  12. Effects of heating and cooling rate on transformation behaviors in weld heat affected zone of low carbon steel; Teitanso koban no yosetsu netsu eikyobu no hentai kyodo ni oyobosu kanetsu reikyaku sokudo no eikyo

    Energy Technology Data Exchange (ETDEWEB)

    Kanetsuki, Y.; Katsumata, M. [Kobe Steel, Ltd., Kobe (Japan)

    1998-01-25

    Discussions were given on effects of welding heat cycles on transformation behaviors in a weld heat affected zone (HAZ). Test pieces are low-carbon fine ferrite pearlite organization steel sheets, which have been treated with a thermomechanical control process (TMCP). The heat cycling was experimented at a maximum temperature of 1350 degC by using a high-frequency heating coil, heating rates from 0.15 to 200 degC/s, cooling rates from 10 to 80 degC/s at an elevated temperature region (higher than 900 degC), and transformation regions (lower than 900 degC) from 0.5 to 6 degC. A transformation curve in actual welding heat cycling was interpreted from these results. Shear-type inverse transformation (from ferrite to austenite) occurs in a rate region corresponding to the heating rate realized during welding. Austenite containing internal stress and a lower structure formed by this inverse transformation accelerates transformation into grain boundary ferrite (GBF) and acerous ferrite (AF). On the other hand, slow cooling in the elevated temperature region releases the internal stress, restores the lower structure, and suppresses the GBF and AF transformation. The GBF tends to precipitate pearlite in adjacent regions and deteriorates the HAZ tenacity. 17 refs., 8 figs., 1 tab.

  13. Electrochemical impedance spectroscopy analysis on effect of steel fiber addition on corrosion of steel rod in mortar; Morutaruchu no tekkin no fushoku ni oyobosu suchiru fuaiba tenka no eikyo no denki kagaku inpidansu supekutorosukopi ni yoru kaiseki

    Energy Technology Data Exchange (ETDEWEB)

    Sakashita, S.; Nakayama, T.; Hamasaki, Y.; Sugii, K. [Kobe Steel Ltd., Kobe (Japan); Sugimoto, K. [Tohoku University, Miyagi (Japan). Department of Metallurgy

    1999-11-15

    The effect of steel fiber (SF) addition to concrete on the corrosion behavior of steel reinforcement was studied by immersion corrosion tests in a 3 mass % NaCl solution for 363 day. The tests were conducted on steel rod/mortar specimens with different SF content (0-2 vol %), and corrosion potentials and electrochemical impedance of the specimens were measured during the tests. Corrosion potentials of the specimens were not so changed by the SF content. Electrochemical impedance measured at corrosion potentials was analyzed to get charge transfer resistance (R{sub ct}) using an equivalent electrical circuit with the R{sub ct}, Warburg impedance and a constant-phase element. The corrosion rate of steel rod in mortar estimated from the reciprocal of the R{sub ct} decreased with increasing of SF content in mortar, and correlated well with the rust area of steel rod measured after immersion corrosion tests. This shows that the electrochemical impedance measurement is the useful diagnosis method of corrosion of steel in concrete. The corrosion inhibition of steel rod in mortar by the SF addition was thought to be attributed to the consumption of dissolved oxygen by the corrosion of SF in mortar. (author)

  14. Effects of dissolved oxygen concentration and flow velocity on corrosion of carbon steel in tap water; Suidosuichu ni okeru tansoko fushoku ni oyobosu yoson sanso nodo to ryusoku no eikyo

    Energy Technology Data Exchange (ETDEWEB)

    Murata, M.; Ouchi, M. [Miura Institute of Research and Development, Ehime (Japan); Fujii, T.; Shiraishi, H.; Kawahito, A. [Miura Co. Ltd., Ehime (Japan)

    1998-05-15

    Discussions were given on the effects of dissolved oxygen (DO) concentration and flow velocity on temporary corrosion of carbon steel in tap water by using a membrane-type deaerator which uses a hollow fiber membrane for air separation. In deaerated air with DO at 0.5 mg per liter, active corrosion took place, in which corrosion rate increases with flow velocity in a range from 0.5 to 2.0 m/s. The corrosion rate in a carbon steel in deaerated air with flow velocity of 0.5 m/s and DO of 0.5 mg per liter decreased to 1/4 to 1/5 of that in non-deaerated water, showing effectiveness in preventing corrosion and red water in pipings in buildings. The corrosion prevention effect is more excellent especially in low flow velocity regions, meaning it being suitable for corrosion prevention in building pipings for water supply which is low in flow velocity and often subjected to stagnation. It was found that, even at about the same flow velocity, the deaerated water is on the safer side than the non-deaerated water. With waters having DO of 2.0 and 4.0 mg per liter, the corrosion rate decreased when flow velocity is higher than 1 m/s, with appearance of passivation trend. There is a relation with high reproducibility between the corrosion rate in the carbon steel and oxygen supply amount, whereas the curve showed a maximum value. This maximum value is thought a transition point from active state corrosion to passive state corrosion. 9 refs., 6 figs., 2 tabs.

  15. Development of elemental analysis by muonic X-ray measurement in J-PARC

    Science.gov (United States)

    Ninomiya, K.; Nagatomo, T.; Kubo, K. M.; Strasser, P.; Kawamura, N.; Shimomura, K.; Miyake, Y.; Saito, T.; Higemoto, W.

    2010-04-01

    Muon irradiation and muonic X-ray detection can be applied to non-destructive elemental analysis. In this study, in order to develop the elemental analysis by muonic X-ray measurement we constructed a new X-ray measuring system in J-PARC muon facility. We performed muon irradiation for Tempo-koban (Japanese old coin) for test experiment of elemental analysis. Muonic X-rays originating from muon transition in muonic silver and gold atoms were identified. The contents of Tempo-koban (Au:56%) was determined by muonic X-ray intensities.

  16. Byen prisme

    DEFF Research Database (Denmark)

    Breitenbauch, Henrik Ø.; Winther, Mark; Jakobsen, Mikkel Broen

    Aleppo, Mosul, Kobane, Palmyra, Fallujah, Raqqa og Ramadi. Listen over byer, hvor der kæmpes eller er blevet kæmpet i Irak og Syrien, er lang. Kampen mod ISIL og den syriske borgerkrig er væsentlige eksempler på, at krigen og byerne i stigende grad er sammenhængende temaer. Verdens befolkningstal...

  17. Fiscal 1997 report on the results of the R and D of industrial scientific technology. R and D of synergistic ceramics (R and D of corrosion prevention technology for the petroleum production system); 1997 nendo sangyo kagaku gijutsu kenkyu kaihatsu seika hokokusho. Synergy ceramics no kenkyu kaihatsu (sekiyu seisan system fushoku boshi gijutsu kenkyu kaihatsu)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-03-01

    To heighten durability and safety of materials/parts for undersea oil drilling, the development of ceramic base materials was made by developing function harmony type process technology which harmonizes on a high grade contrary characteristics and various functions. The paper summed up the fiscal 1997 results. In the design of system formation, computational simulation technology was developed to the composite process and the diploid system. The development of multifunction simultaneous manifestation materials was trially made by the higher nano structure process. A study was made of control of microstructures of porous materials and matrix filling by the gas phase precipitation control. Proposed were selective control of grain growth from species crystals and the columnar particle orientation laminated structure of simultaneous manifestation of strength and toughness. By composite precipitation reaction control, studied were simultaneous dispersion of whisker and increase in density of matrixes, and harmonization with long fibers. Silicon nitride was trially made with low lubrication/friction coefficients and high strength. A simulation method for crack progress behavior evaluation was developed using a testing notched specimen heterogeneous microstructures. Analyses were made of brittle fracture mechanics and reliability evaluation. 273 refs., 344 figs., 29 tabs.

  18. Die Kurden und der Islamische Staat

    OpenAIRE

    Küper-Büsch, Sabine

    2015-01-01

    Teil VIII unserer Serie zum “Islamischen Staat”: "Blogforum 'Kalifat des Terrors: Interdisziplinäre Perspektiven auf den Islamischen Staat". Die Kurden feiern in diesen Tagen den Sieg über den Islamischen Staat in Kobane. Die Hauptstadt des Distrikts Ain al-Arab im Gouvernement Aleppo in Syrien liegt nahe der syrisch-türkischen Grenze. Seit Anfang 2014 ist Ain al-Arab Zentrum eines der drei selbstverwalteten Kantone Rojavas. Diese Kantone stehen unter der Kontrolle der kurdischen “Partei ...

  19. Simultaneous discrimination of speed is more difficult than simultaneous discrimination of size for both pigeons and people

    Directory of Open Access Journals (Sweden)

    Olga F. Lazareva

    2017-08-01

    Full Text Available Previous reports suggest that pigeons are highly sensitive to speed of motion (Cook, Beale, Koban, 2011; Herbranson, Fremouw, & Shimp, 2002. In contrast, we found that pigeons required more extensive training to learn speed discrimination than size discrimination (Lazareva, Young, & Wasserman, 2014. However, our results were based on a comparison of two experiments conducted in different laboratories, complicating the interpretation of the data. Here, we trained pigeons to perform size discrimination or speed discrimination in a two-alternative simultaneous discrimination task using a within-subject design. All birds acquired size discrimination much faster than speed discrimination, confirming our prior report. We further explored pigeons’ sensitivity to differences in speed and size by training them to discriminate two end-point stimuli in a two-alternative forced-choice task and then presenting a wide range of testing stimuli located between the training end-point stimuli. The results again indicated weaker control by the differences in speed in comparison to size; comparable results were obtained for human participants.

  20. Temperature and bath gas composition dependence of effective fluorescence lifetimes of toluene excited at 266 nm

    Science.gov (United States)

    Faust, S.; Dreier, T.; Schulz, C.

    2011-05-01

    Time-resolved fluorescence spectra of gas-phase toluene upon picosecond excitation at 266 nm were investigated as a function of temperature (296-1074 K) and bath gas composition (varying amounts of N 2, O 2, and CO 2) at 1 bar total pressure with a temporal resolution of 50 ps. In the investigated temperature range the effective fluorescence lifetime drops with increasing temperature from 46 ± 3 ns to 0.05 ± 0.01 ns in N 2 and CO 2. In the presence of O 2 at constant temperature the lifetimes also decrease significantly (e.g., from 46 ± 3 ns without O 2 to 0.63 ± 0.05 ns in air at room temperature), whereas lifetimes are independent on the CO 2 concentration. The implications of the results for the existing phenomenological model of predicting temporally integrated fluorescence intensities in toluene [W. Koban, J.D. Koch, R.K. Hanson, C. Schulz, Appl. Phys. B 80 (2005) 777] are discussed.