Study of surface layer on 08Kh15N5D2T steel

International Nuclear Information System (INIS)

Tyurin, A.G.; Povolotskij, V.D.; Zhivotovskij, Eh.A.; Berg, B.N.

1986-01-01

08Kh15N5D2T steel phase composition is investigated. Its surface layer was determined by X-ray diffraction analysis method. It is shown, that a subscale appears to be the reason for corrosion of products, made of EhP410 steel. Under the existing smelling technology the carbon content in it is ≥ 0.05%. Therefore to avoid the metal surface depletion with chromium, one must provide for titanium relation to carbon of not less than 4.5 and carry out the rolled product thermal treatment in a protective atmosphere; otherwise, the technology must include not only the removal of scale from steel but the metal subscale layer as well

Ductility of high chromium stainless steels

International Nuclear Information System (INIS)

Peretyat'ko, V.N.; Kazantsev, A.A.

1997-01-01

Aimed to optimize the hot working conditions for high chromium stainless steels the experiments were carried in the temperature range of 800-1300 deg C using hot torsion tests and cylindrical specimens of ferritic and ferritic-martensitic steels 08Kh13, 12Kh13, 20Kh13, 30Kh13 and 40Kh13. Testing results showed that steel plasticity varies in a wide range depending on carbon content. Steels of lesser carbon concentration (08Kh13 and 12Kh13) exhibit a sharp increase in plasticity with a temperature rise, especially in the interval of 1200-1250 deg C. Steels 20Kh13 and 30Kh13 display insignificant plasticity increasing, whereas plastic properties of steel 40Kh13 increase noticeably in the range of 1000-1300 deg C. It is shown that optimal hot working conditions for specific steel must be selected with account of steel phase composition at high temperatures

Reliability and durability of the 12Kh1MF steel tubes of electroslag remelting and their welded joints

International Nuclear Information System (INIS)

Lanskaya, K.A.; Kulikova, L.V.; Mazel', R.E.; Khromchenko, F.A.; Strizhenova, V.F.

1978-01-01

Results of investigating the positive effect of electrolag remelting (ESR) on the properties of the base metal and welded joint of the 12Kh1MF steel steam pipes with the aim of increasing their durability up to 20,000 hrs, are presented. To estimate the quality and properties of tube billet metal, microstructure, content and nature of nonmetallic inclusions, content of gases, austenite grain size, austenite transformations during continuous cooling, metal ductility, mechanical properties at different temperatures and heat resisting properties, have been investigated. It is established, that the base metal in tubes of electroslag remelting possess higher heat resistance, while welded joints besides, have high deformability and resistance to brittle fracture

Effect of nickel and MnS inclusions in the metal on the pitting corrosion of low-carbon stainless steels

International Nuclear Information System (INIS)

Frejman, L.I.; Nguen, The Dong; Volkov, D.E.; Konnov, Yu.P.

1986-01-01

The resistance to pitting corrosion of steels on the 03Kh17-03Kh18 base containing up to 20 % Ni at different levels of S and Mn impurities contamination is investigated. It is shown that up to 50 % of nickel introduced into ordinary steels with 5-6 % Ni is spent to compensate the resistance decrease caused by MnS inclusions. Full compensation is not attained even in the 10-20 %. Ni range in which nickel practically does not affect the resistance of neither ordinary, nor pure (without MnS) steels. Titanium introduction into ordinary steel on the Kh22N6 base permits to surpass the level of 03Kh17N3 pure steel resistance and attain the level of 03Kh17N6 pure steel almost by all characteristics (including passivated characteristics in sulfuric acid) besides pitting repassivity. In this property pure steels with Ni >or approx. 3 % surpass even the molybdenum containing 03Kh21NbM2T ordinary steel though they by far concede by passivation in sulfuric acid

Nitrogen effect on the tendency of Cr-Ni-MN steels to delayed fracture under stress and hydrogen effects

International Nuclear Information System (INIS)

Suvorova, S.O.; Fillipov, G.A.

1996-01-01

Austenitic steels types 03Kh17N16G10AM5, 03Kh6N12G10AM5 and 07Kh13AG20 with various nitrogen contents were studied for their tendency to delayed fracture using mechanical tests, fractography and X ray diffraction analysis. The steel type 07Kh13G20 exhibited the highest strength in the initial state but showed an increase tendency to delayed fracture after hydrogenation. It is underlined that nitrogen additions essentially intensify the tendency of cold worked steels to delayed fracture. This fact should be taken into account when using nitrogen-containing Cr-Ni-Mn steels under severe operational conditions. 4 refs., 2 tabs

Effect of silicon on the structure, tribological behaviour, and mechanical properties of nitrogen-containing chromium-manganese austenitic steels

International Nuclear Information System (INIS)

Korshunov, L.G.; Chernenko, N.L.; Gojkhenberg, Yu.N.

2003-01-01

The effect of silicon in quantity of 3.5-4.5 mass. % on tribological behaviour is studied for nitrogen-bearing (0.20-0.52 mass. % of nitrogen) chromium-manganese austenitic steels (10Kh15G23S4A0.20, 10Kh16G17N3S4A0.30, 10Kh19G20NS4A0.50, 12Kh19G19NS2A0.50, 10Kh18G19A0.50, 08Kh16G8N10S4A0.18). Mechanical properties and corrosion resistance of the steels are determined. Using metallographic, x-ray diffraction and electron microscopical methods a study is made into structural transformations running in the steels considered under friction and static tension. It is shown that additional silicon alloying of nitrogen-bearing chromium-manganese austenitic steels results in an essential increase of adhesion wear resistance of the materials on retention of low friction coefficient (f=0.25-0.33). A strong silicon effect on steel tribological behaviour is related with planar slip activation and with an increase of austenite strength and heat resistance [ru

Heat treatment effect on impact strength of 40Kh steel

International Nuclear Information System (INIS)

Golubev, V.K.; Novikov, S.A.; Sobolev, Yu.S.; Yukina, N.A.

1984-01-01

The paper presents results of studies on the effect of heat treatment on strength and pattern of 40Kh steel impact failure. Loading levels corresponding to macroscopic spalling microdamage initiation in the material are determined for three initial states. Metallographic study on the spalling failure pattern for 40Kh steel in different initial states and data on microhardness measurement are presented

The effect of thermal treatment on corrosion properties of 0Kh15N16M3B stainless steel tested in the N2O4 boiling medium

International Nuclear Information System (INIS)

Kamenev, A.Ya.; Kopets, Z.V.; Mel'nikova, N.N.; Dergaj, A.M.; Fedyushin, E.E.

1985-01-01

The experimental data on the effect of thermal treatment on corrosion properties of stainless steel 00Kh16n15m3b tested in the N 2 O 4 boiling medium at 8.0 MPa and 433 K are presented. The electron microscope data on steel microstructure after different heat treatments and phase composition of oxide films emerging at corrosion test are given. It is shown, that the rise of the heat treatment temperature from 823 up to 1023 K increases total corrosion of 00Kh16n15m3b steel under given test conditions and practically does't affect intercrystalline corrosion. Developed oxide layers are of deposited nature and doesn't affect markedly the rate of progress of the corrosive processes. Taking into account high chromium volatility in vacuum one can assume that at the initial stages of the coolant effect, the process of depletion of steel surface by chromium durng heat treatment affects markedly steel corrosion stability

Effect of nonmetallic inclusions on anisotropy of ductility in 35KhN3MFA steel forgings

International Nuclear Information System (INIS)

Shtremel', M.A.; Yavojskij, V.I.; Volkov, V.A.; Chursin, G.M.; Chukhlov, V.I.; Fetisov, G.I.; Mochalin, N.K.; Smol'yaninov, L.V.

1980-01-01

Characteristics of nonmetaltic inclusions and anizotropy of ductility and of impuct strength of forgings of the 35KhN3MFA steel are compared at different variants of melting and outer-furnace treatment. It is shown that method of melting rugulates anisotropy of ductility primarily through deformability of large inclusions during forging. Deformability of inclusions considerably changes due to introduction of silicocalcium in iron mold [ru

Effect of the isothermal transformation temperature on the fine structure of steel-12Kh1MF

International Nuclear Information System (INIS)

Mints, I.I.; Berezina, T.G.; Lanskaya, K.A.

1976-01-01

For detailed analysis of bainite and pearlite in steel 12Kh1MF, homogeneous structures were obtained by isothermal annealing at 350, 450, 500, and 650 0 for 1 h. Isothermal transformation of austenite leads to the formation of bainite at 350-500 0 and pearlite at 650 0 . The austenitizing temperature was 980 0 for both types of samples, with holding for 20 min. For comparison, the plates were quenched from 980 0 and 1050 0 in ice-cold brine. The investigation was conducted with use of light and electron microscopes and x-ray analysis. The long-term strength was also determined. Isothermal treatment of steel 12Kh1MF at 350-500 0 C leads to the formation of a structure consisting of upper and lower bainite. At 500 0 the structure consists primarily of upper bainite, and at 350 0 of lower bainite. With tempering of the steel with a structure of upper and lower bainite at 730 0 for 3 h the dislocations undergo redistribution of the polygonization type within ferrite needles, with development of a cellular substructure. The acicular structure of the matrix is retained in this case. The density and evenness of the distribution of carbides is higher in upper bainite than in lower bainite. Steel 12Kh1MF with a structure of upper bainite is more susceptible to recrystallization as compared with a structure of lower bainite, which is responsible for the higher heat resistance of the latter

Estimation of structural strength of 38KhN3MFA steel, melted using different methods

International Nuclear Information System (INIS)

Kudrya, A.V.; Mochalov, B.V.; Fadeev, Yu.I.

1982-01-01

Quantity of steel melted by different methods using criteria of fracture mechanics is evaluated. Three technological variants of the 38KhN3MFA steel melting: acid Martin steel prepared by the duplex-process (melt 1); the main Martin steel melting with deoxidation and alloying in a ladle by liquid alloy and treatment with synthetic slag with argon purging after production (melt 2) and its electroslag remelt - ESP process (melt 3) are investigated. The analysis of the investigated melts has revealed that crack resistances of the acid Martin steel is higher than that of other melts at practically similar standard mechanical properties with 0.35 probability at 0.05 significance level in the low-tempered state; in the tempered state the best crack resistance is observed in the ESP main Martin steel. Metal of the main Martin melting has lower crack resistance as compared with other meltings at both strength levels. The results of the work point out the necessity of applying the criteria of fracture mechanics for obtaining an objective evaluation of the steel quality

Ductile fracture of two-phase welds under 77K. [Steel-EhP810, steel-EhP666, steel-08Kh18N10T, steel-EhP659-VI, steel-chP810

Energy Technology Data Exchange (ETDEWEB)

Yushchenko, K.A.; Voronin, S.A.; Pustovit, A.I.; Shavel' , A.V.

The effect of the type of welding and fillers on crack resistance of welded joints high-strength steel EhP810 and its various compounds with steels EhP666, 08Kh18N10T has been studied. For the welding of steel EhP810 with steels EhP810, EhP666, 08Kh18N10T electron-beam, automatic, argon tungsten arc with non-consumable electrode with various fillers, as well as argon metal-arc welding with consumable electrode, were used. It is shown, that for a joint, made by electron-beam welding, parameters sigmasub(u), Ksub(IcJ), KCV are higher than for a joint of a similar phase structure made using filler wire EhP659-VI. It is explained by the fact, that during electron-beam welding joint metal refining takes place, which removes gases. In welded joints of chP810 steel, having joints with austenitic structure, characteristic of crack resistance Ssub(c) increases by more than 0.2 mm in contrast to two-phase joints, which conventional yield strength at 77 K exceeds 1000 MPa. It is worth mentioning, that for other classes of steels formation of two-phase structure of joint increases welded joint resistance to brittle fracture. It is possible to obtain the required structure of joint with assigned level of resistance to brittle fracture by means of the use of different fillers, optimum and welding procedure, regulating the part of the basic metal in joint content.

Effect of metal properties of casts of steel-15Kh1M1FL on the crack resistance at 565 deg C

International Nuclear Information System (INIS)

Gladshtejn, V.I.; Sheshenev, M.F.

1976-01-01

Results are given of prolonged tests of the metal of industrial casts with various fluidity limits. It has been shown experimentally that a quite satisfactory crack resistance is characteristic of a metal with a fluidity limit in the range 30-50 kgf/mm 2 . Metallographic studies have been conducted. Upon variation of the structure and properties of the 15Kh1M1FL steel during operation, the rate of growth of small cracks (up to 2.0 mm) decreases almost by 3 orders of ten (from 1.4x10 -4 to 2.0x10 -7 mm/hour). Subsequent structural changes during prolonged operation (over 50000 hours) result in a gradual increase in the rate of crack growth. At the same time resistance towards appearance of the impermissible high rate of the crack growth, Ksub(10sup(-3)), diminishes monotonically with the operation time. The metal of industrial 15Kh1M1FL steel casts has good crack resistance (Ksub(10sup(-3)) =30-70 kgf/mmsup(3/2) and Vsub(ef) =) kgf/mm 2 ) and a satisfactory local plasticity (critical opening being no more than 0.20 mm for 10 3 hours)

Effect of partial oxygen pressure on physicochemical properties of Kh18N10T steel at isothermal oxidation

International Nuclear Information System (INIS)

Alekseev, V.N.; Oshe, E.K.; Fokin, M.N.; Bogdanova, S.V.; Loskutov, A.I.

1990-01-01

Auger-electron spectroscopy, photoelectric polarization, conductometry methods have been used to analyze chemical and defect composition of surface oxide layers, formed on stainless steel Kh18N10T in vacuum (10 -9 - 10 -2 torr) and at temperatures 593-673 K. The boundary conditions of manifestation of extermal behaviour of the dependence of the surface oxide growth rate at isothermal oxidation of this steel are determined. The relation between passivation properties of the surface oxide and the magnitude of the edge angle of the surface wetting with molten tin is revealed

Damping capacity of unstable steels on chromium-nickel-manganese base

Energy Technology Data Exchange (ETDEWEB)

Kochkin, L.I.; Rudakov, A.A. (Kirovskij Politekhnicheskij Inst. (USSR))

1982-02-01

The paper deals with results of a study on the energy scattering in OKh13N3G8, 20Kh13N3G4 and 30Kh13N3G4 unstable steels. It is shown that the development of microplastic strains most easily occurs in low-carbon steel having a two-phase structure in the initial state. The proceeding of microplastic deformations in carbon unstable steels is limited by the interstitial atom effect on the dislocation movement. It is established that in OKh13N3G8 steel the martensite ..cap alpha --> gamma..- transformation begins under the cyclic stress amplitudes below the yield point of this steel. The steels studied possess a high vibrostrength.

Technical Note: Calibration device for the krypton hygrometer KH20

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T. Foken

2012-08-01

Full Text Available A calibration device for krypton hygrometers (KH20, Campbell Scientific, Inc. with variable path length is presented. This unit allows for in-situ calibrations of the krypton hygrometer, which is typically not very stable over time, during measuring campaigns. It was constructed mainly for application at high altitudes and low temperatures, where further improvements are needed to the IR-hygrometers which are normally used. The changing path length requires that a changing concentration of the absorber be simulated. Because oxygen absorbs more strongly than water vapour, the calibration is made against oxygen and transferred to water vapour. The design of the calibration instrument is made as one unit containing a stepper motor system, PC and humidity sensor. For the calibration, it is necessary to install the krypton hygrometer on this unit.

Metallographical procedure for detecting carburized layer in the 12Kh18N10T steel tubes

International Nuclear Information System (INIS)

Najmark, S.I.; Shmalenyuk, R.P.

1977-01-01

The various causes of the tendency to intercrystalline corrosion of stainless steel tubing were studied. 12Kh18N10T steel tube specimens were metallographically investigated to reveal the presence and depth of the carburized layer. Unlubricated specimens and specimens with the graphite-saltpeter lubrication applied on them were austenized in the temperature range from 950 to 1250 deg C and then exposed to a provoking anneal at 650 deg C for 24 h. All the lubricated specimens showed a carbide network along grain boundaries and intercrystalline cracks. The specimens treated without lubrication had no cracks. The method offered can differentiate poor tube cleaning and the undesirable effect of other processing steps on the tubes

Damping capacity of unstable steels on chromium-nickel-manganese base

International Nuclear Information System (INIS)

Kochkin, L.I.; Rudakov, A.A.

1982-01-01

The paper deals with results of a study on the energy scattering in OKh13N3G8, 20Kh13N3G4 and 30Kh13N3G4 unstable steels. It is shown that the development of microplastic strains most easily occurs in low-carbon steel having a two-phase structure in the initial state. The proceeding of microplastic deformations in carbon unstable steels is limited by the interstitial atom effect on the dislocation movement. It is established that in OKh13N3G8 steel the martensite α→γ- transformation begins under the cyclic stress amplitudes below the yield point of this steel. The steels studied possess a high vibrostrength [ru

Welding of heterogeneous 12Kh2MFSR steels with the Mn-Cr-Si-Ni system

International Nuclear Information System (INIS)

Smirnov, A.N.; Belogolov, E.I.

1978-01-01

The process of welding pipes of the 12Kh2MFSR pearlitic steels and austenitic steels of the Mn-Cr-Si-Ni system was studied. The filler materials were selected, and the working capacity of welded joints was examined in ageing and cyclic heatings. The microhardness of steels was measured, and the ultimate strength of welded joints was determined. The following has been established: the composite joints of steels of the Mn-Cr-Si-Ni system and 12Kh2MFSR steel are advisable to be welded on a coating layer welded by the EhA395/9 electrodes on the surface of a pipe of the 12Kh2MFSR pearlitic steel; this guarantees the sufficient working capacity of welded joints

Development and industrial mastering hot rolling procedure for low-ductile steels and alloys

International Nuclear Information System (INIS)

Degterenko, V.K.; Sokolov, V.A.

1980-01-01

The technique for the development of the sheet hot rolling procedure for low-ductile steels and alloys (0Kh17N14M2, 12Kh21N5T, 20Kh25N20C2,40Kh13, 36NKhTYu etc.) is proposed, using plastometer which permits to obtain the data on the deformation resistance in the wide range of temperatures (800-1300 deg C), of deformation degrees (0.1-0.3) and deformation rates (0.001-300 c -1 ). With the help of the plastometric data processed on the computer the calculation of the rolling regimes for the sheet with improved surface quality is carried out at the more uniform loading on the mill stands

Structural changes IN THE Kh20N45M4B nickel alloys and THE Kh16N15M3B steel due to helium ion bombardment

International Nuclear Information System (INIS)

Kalin, B.A.; Chernikov, U.N.; Chernov, I.I.; Kozhevnikov, O.A.; Shishkin, G.N.; Yakushin, V.L.

1986-01-01

Using transmission electron microscopy, x-ray structural analysis, and the thermal desorption techniques, the authors carried out a detailed study of the structural and phase changes, defect formation, and helium accumulation in the He + -bombarded 16-15 austenitic steels and 20-45 nickel alloys. Microstructure of the bombarded specimens was studied using the methods of transmission electron microscopy of thin foils in the EVM-100, and EM-301G electron microscopes. Results of x-ray studies on the bombarded specimens are presented. The conducted studies show that bombardment of structural materials with light ions can lead to significant structural damages and changes in the chemical and phase composition of the surface layer. The possible mechanisms of the changes in the chemical and phase composition include selective sputtering and radiation-induced accelerated diffusion of elements in the field of internal lateral stresses developing during the He + implantation process

Hardening and stress relaxation during repeated heating of 15Kh2MFA and 15Kh2NMFA steels welded joints

International Nuclear Information System (INIS)

Zubchenko, A.S.; Suslova, E.A.

1986-01-01

Results of investigation of temperature-time conditions of hardening of welded joints of 15Kh2MFA and 15Kh2NMFA steels and their relaxation resistance, effect of metal structure of imitated heat affected zone (HAZ) on intensity of precipitation hardening at repeated heating are presented as well as the results of the process of relaxation of residual stresses at welded joints samples heating carried out by automatic welding under the flux with the use of adding materials and technology of manufacturing of vessels of WWER-440 and WWER-1000 reactors. Peculiarities of the hardening at repeated heating of the HAZ metal imitated at these steels. Precipitation hardening of overheated 15Kh2MFA steel is connected with precipitations at repeated heating of carbides of the M 7 C 3 , M 3 C and VC type. Stress relaxation in welded joints runs more intensively at the initial stage of repeated heating, i.e. during the same period of the process of dispersed carbide precipitations

Effect of hydrostatic pressure on phase transformations in Kh17N8 steel during deformation

International Nuclear Information System (INIS)

Eshchenko, R.N.; Teplov, V.A.

1984-01-01

The phase composition and structure of Kh17N8 steel strained to different degrees under atmospheric pressure and 1700 MPa are investigated. It has been found that deformation at 1700 MPa causes α and epsilon-martensite formation, the same deformation under atmospheric pressure - only α-martensite formation. The amount of the formed α-martensite is not changed with application of hydrostatic pressure. Electron-microscopic observations have shown that the dispersion of α-martensite formed under pressure is higher than in the absence of pressure; no interconnection in formation of α and epsilon-martensite in samples strained under pressure has been observed

Hot working effect on austenite transformations in structural steel in continuous cooling

International Nuclear Information System (INIS)

Zajmovskij, V.A.; Kisteh, N.V.; Samedov, O.V.

1979-01-01

Austenite transformations in 40, 40Kh, 40KhN and 40KhNMA steels under hot working at 900 deg C with 20% reduction degree and continuous cooling with 1,7-16 0 /s are investigated. Changing of cooling rate in various ways affects the temperature range of austenite transformation in pearlite and bainite regions. Regulating the cooling rate after hot working one can essentially change the impact strength and steel ductility as a result of high temperature thermomechanical treatment effect

Structure, mechanical and corrosion properties of powdered stainless steel Kh13

International Nuclear Information System (INIS)

Radomysel'skij, I.D.; Napara-Volgina, S.G.; Orlova, L.N.; Apininskaya, L.M.

1982-01-01

Structure, mechanical and corrosion properties are studied for compact powdered stainless steel, Grade Kh13, produced from prealloyed powder and a mixture of chromium and iron powders by hot vacuum pressing (HVP) following four schemes: HVP of unsintered billets; HVP of presintered billets; HVP of unsintered billets followed by diffusion annealing; HVP of sintered billets followed by diffusion annealing. Analysis of the structure, mechanical and corrosion properties of Kh13 steel produced according to the four schemes confirmed that production of this steel by the HVP method without presintering of porous billets and diffusion annealing of compact stampings is possible only when prealloyed powder of particular composition is used as a starting material

Determination of constant of chemical reaction rate in the process of steel treatment in the endothermal atmosphere

International Nuclear Information System (INIS)

Gyulikhandanov, E.L.; Kislenkov, V.V.

1978-01-01

The high-temperature method was applied to measuring a relative variation in the electrical resistance of a thin steel foil prepared from the 12KhN3A, 18Kh2N4VA, 20KhGNR, and 20Kh3MVF steels during its carburization and decarburization, and determined was the temperature dependence of the reaction rate of the interaction of the endothermal atmosphere of different compositions with the analloyed γ-Fe. A connection has been established between the reaction rate constant and the thermodynamic activity of carbon in the alloyed austenite at the temperature of about 925 deg C, corresponding to the cementation temperature. This provides the quantitative estimation of the above value for any alloyed steels and with the presence of numerical values of diffusion coefficients; this also enables one to carry out an accurate calculation of the distribution of carbon throughout the depth of a layer when effecting the cementation in the endothermal atmosphere

Features of argon-arc welding of aluminium alloy AD1 to stainless steel 12Kh18N10T

International Nuclear Information System (INIS)

Sadov, I.I.

1982-01-01

Welding of pipes made of the 12Kh18N10T stainless steel and the AD1 aluminium alloy is proposed to perform using one-sided aluminizing. It is recommended to use shields in order to protect internal and external surfaces of pipes, aluminizing of which is impossible. It is shown that developed technological process for welded joints made of aluminium and stainless steel for cryogenic apparatus permits to create light-duty cryostat assembly using aluminium alloys instead of copper alloys, to increase reliability of apparatus (usage of welded joints instead of soldered ones), and to improve labour conditions

Additional materials for welding of the EP99 heat resisting alloy with the EI868 alloy and 12Kh18N9T steel

International Nuclear Information System (INIS)

Sorokin, L.I.; Filippova, S.P.; Petrova, L.A.

1978-01-01

Presented are the results of the studies aimed at selecting an additive material for argon-arc welding process involving heat-resistant nickel EP99 alloy to be welded to the EI868 alloy and 12Kh18N9T steel. As the additive material use was made of wire made of nickel-chromium alloys and covered electrodes made of the EP367 alloy with additions of tungsten. It has been established that in order to improve the resistance of metal to hot-crack formation during argon arc welding of the EP99 alloy with the EI868 alloy, it is advisable to use an additive material of the EP533 alloy, and while welding the same alloy with the 12Kh18N9T steel, filler wire of the EP367 alloy is recommended

Effect of agressive medium movement of local corrosion of the steel - 12Kh18N10T

International Nuclear Information System (INIS)

Makartsev, V.V.; Pakhomov, V.S.; Abramova, I.M.

1980-01-01

The effect of agressive medium movement on the formation of pitting corrosion of the 12Kh18N10T stainless steel in the acidic chloride-nitrate solution at room temperature is studied. It is established that the agressive medium movement hinders the formation of pitting corrosion at potentials more negative than +0.4 V and practically does not affect it at more positive potentials. The investigations have been carried out on a disc electrode rotating at a speed from 0 to 2000 rot./min

Effect of partial oxygen pressure on physicochemical properties of Kh18N10T steel at isothermal oxidation. Vliyanie partsial'nogo davleniya kisloroda na fiziko-khimicheskie svojstva poverkhnosti stali Kh18N10T pri izotermicheskom okislenii

Energy Technology Data Exchange (ETDEWEB)

Alekseev, V N; Oshe, E K; Fokin, M N; Bogdanova, S V; Loskutov, A I [AN SSSR, Moscow (USSR). Inst. Fizicheskoj Khimii

1990-10-01

Auger-electron spectroscopy, photoelectric polarization, conductometry methods have been used to analyze chemical and defect composition of surface oxide layers, formed on stainless steel Kh18N10T in vacuum (10{sup -9} - 10{sup -2} torr) and at temperatures 593-673 K. The boundary conditions of manifestation of extermal behaviour of the dependence of the surface oxide growth rate at isothermal oxidation of this steel are determined. The relation between passivation properties of the surface oxide and the magnitude of the edge angle of the surface wetting with molten tin is revealed.

The microstructure of a small scale AISI 316 stainless steel pumped sodium loop following operation for 20,000h

International Nuclear Information System (INIS)

Charnock, W.; Gwyther, J.; Marshall, P.

1980-08-01

A small pumped loop constructed of AISI 316 stainless steel has been operated for 20,000 hrs. with a peak temperature of 635 0 C. Marked decarburisation was observed in the preheater and in the adjacent specimen chamber. No regions of significant carburisation were found. The decarburisation of the heat input areas appears to be a consequence of the large temperature difference between the hot and cold legs. In addition the steel temperatures in the hot regions are such as to allow relatively high solid state mobility of carbon. The absence of significant carburisation in other parts is attributed to the lower temperatures which leads to a gradual reduction in carbon activity over a sink area which is large in relation to that of the source. Additionally, the mobility of carbon is reduced at the lower temperatures found in the cooler regions of the loop. Tentatively applying the results to a fast reactor circuit suggests the occurrence of decarburisation in the high heat input regions ie the fuel clad, with corresponding but more widely distributed, and hence less significant, carburisation in other regions. (author)

Structural inheritance in cast 30KhGNM-type steel

International Nuclear Information System (INIS)

Sadovskij, V.D.; Bershtejn, L.I.; Mel'nikova, A.A.; Polyakova, A.M.; Schastlivtsev, V.M.

1980-01-01

Structural inheritance in the cast 30KhGNM-type steel depending on the heating rate and the temperature of preliminary tempering is investigated. When eating the cast steel with a beinite structure at the rate of 1-150 deg/min, the restoration of austenite grain and the following recrystallization due to the phase cold work, are observed. Slow heating from room temperature or preliminary tempering hinder grain restoration during heating. A non-monotonous effect of tempering temperature on the structural inheritance is established which can be connected with the kinetics of decomposition of residual austenite in steel

Development of production technology and investigation of quality for forged-welded turbine rotors of steel 25Kh2NVFA

International Nuclear Information System (INIS)

Borisov, I.A.; Merinov, G.N.; Slezkina, E.V.

1997-01-01

A study was made into mechanical properties and microstructure of turbine rotor components manufactured by forging and heat treated under various conditions. It is revealed that the optimal heat treatment of forgings must include double quenching with subsequent tempering at 630-640 deg C for 10-20 h. Forged and welded rotors should be tempered at 620-630 deg C for 50-100 h. Microscopic examination and mechanical tests showed that low alloy steel 25Kh2NMF can be successfully used for manufacturing rotors of high-, medium-and low-heat turbines

Welding of heat-resistant 20% Cr-5% Al steels

International Nuclear Information System (INIS)

Tusek, J.; Arbi, D.; Kosmac, A.; Nartnik, U.

2002-01-01

The paper treats welding of heat-resistant ferritic stainless steels alloyed with approximately 20% Cr and 5% Al. The major part of the paper is dedicated to welding of 20% Cr-5% Al steel with 3 mm in thickness. Welding was carried out with five different welding processes, i. e., manual metal-arc, MIG, TIG, plasma arc, and laser beam welding processes, using a filler material and using no filler material, respectively. The welded joints obtained were subjected to mechanical tests and the analysis of microstructure in the weld metal and the transition zone. The investigations conducted showed that heat-resistant ferritic stainless 20% Cr-5% Al steel can be welded with fusion welding processes using a Ni-based filler material. (orig.)

Wear resistance and structural changes in nitrogen-containing high-chromium martensitic steels under conditions of abrasive wear and sliding friction

International Nuclear Information System (INIS)

Makarov, A.V.; Korshunov, L.G.; Schastlivtsev, V.M.; Chernenko, N.L.

1998-01-01

Martensitic nitrogen-containing steels Kh17N2A0.14, Kh13A0.14, Kh14G4A0.22 as well as steel 20Kh13 were studied for their wear resistance under conditions of friction and abrasion. Metallography, X ray diffraction analysis and electron microscopy were used to investigate the structural changes taking place in a thin surface layer on wearing. It is shown that an increase of nitrogen content of 0.14 to 0.22% promotes an enhancement of steel resistance to abrasive and adhesive wear, especially after tempering in the range of 500-550 deg C. Typically, the nitrogen-containing steels exhibit lower resistance to various types of wear in comparison with the steels with high-carbon martensite due to their lower deformability under conditions of friction loading

Plasticity of low carbon stainless steels

International Nuclear Information System (INIS)

Bulat, S.I.; Fel'dgandler, Eh.G.; Kareva, E.N.

1975-01-01

In the temperature range 800-1200 0 C and with strain rates of from 10 -3 to 3 s -1 , austenitic (000Kh18N12) and austenitic-ferrite (000Kh26N6) very low carbon stainless steels containing 0.02-0.03% C exhibit no higher resilience than corresponding ordinary steels containing 0.10-0.12% C. However, the plasticity of such steels (particularly two-phase steels) at 900-1100 0 C is appreciably inferior owing to the development of intergranular brittle fracture. Pressure treatment preceded by partial cooling of the surface to 850 0 C yields rolled and forged products with acceptable indices but is inconvenient technically. At the Zlatoustovsk and Ashin metallurgical plants successful tests have been performed involving the forging and rolling of such steels heated to 1280-1300 0 C without partial cooling; it was necessary to improve the killing conditions, correct the chemical composition (increasing the proportion of ferrite) and take measures against heat loss. (author)

Effect of Cr, Ni, and Mo additions on the susceptibility of the 0Kh6n7m7c steel to hot cracking

International Nuclear Information System (INIS)

Tolstykh, L.G.; Pryakhin, A.V.; Popov, A.N.; Usynin, V.F.

1977-01-01

The effect of chromium, molybdenum, and nickel on the tendency of surfacing materials to form hot cracks (Vsub(kp) was studied using the mathematical statistics method. The St3 steel and 38KhN3MFA steel were used in the study. A device facilitating the hot cracking tendency test procedure was developed. It was found that, in the concentration range involved, Ni and Mo produce no effect on Vsub(kp), and Cr enhances it. A new powder wire, PP-OKh7N8M6S, capable of increasing surface material resistance by 1.5-2 times, has been developed

Application of experiment planning during investigation of cementation process in solid carburizers

International Nuclear Information System (INIS)

Lisenkov, A.N.; Denisov, V.M.; Prigozhina, E.L.

1981-01-01

A mathematical model of cementation process in solid carburizirs is obtained, the most effective contents of carburizers are chosen. Specimens are produced out of St20, 12KhN3A, 40Kh13, KhVG steels. It is shown that specimens of St20 and 12KhN3A steels have the higher depth of cementated layer, specimens made of 40Kh13 and KhVG steels-the lower depth. It is shown that the quality of cementated layer structure at recommended regimes improved, cementated layer depth for low-carbon steels changed a little and for tool steels increased infficiently: for KhVG steel in 2-3 times for 40Kh13 steel in 1.5-2.5 times

Experimental study of residual stresses in laser clad AISI P20 tool steel on pre-hardened wrought P20 substrate

International Nuclear Information System (INIS)

Chen, J.-Y.; Conlon, K.; Xue, L.; Rogge, R.

2010-01-01

Research highlights: → Laser cladding of P20 tool steel. → Residual stress analysis of laser clad P20 tool steel. → Microstructure of laser clad P20 tool steel. → Tooling Repair using laser cladding. → Stress reliving treatment of laser clad P20 tool steel. - Abstract: Laser cladding is to deposit desired material onto the surface of a base material (or substrate) with a relatively low heat input to form a metallurgically sound and dense clad. This process has been successfully applied for repairing damaged high-value tooling to reduce their through-life cost. However, laser cladding, which needs to melt a small amount of a substrate along with cladding material, inevitably introduces residual stresses in both clad and substrate. The tensile residual stresses in the clad could adversely affect mechanical performance of the substrate being deposited. This paper presents an experimental study on process-induced residual stresses in laser clad AISI P20 tool steel onto pre-hardened wrought P20 base material and the correlation with microstructures using hole-drilling and neutron diffraction methods. Combined with X-ray diffraction and scanning electron microscopic analyses, the roles of solid-state phase transformations in the clad and heat-affected zone (HAZ) of the substrate during cladding and post-cladding heat treatments on the development and controllability of residual stresses in the P20 clad have been investigated, and the results could be beneficial to more effective repair of damaged plastic injection molds made by P20 tool steel.

The Kinetics of Bainitic Transformation of Roll Steel 75Kh3MF

Science.gov (United States)

Kletsova, O. A.; Krylova, S. E.; Priymak, E. Yu.; Gryzunov, V. I.; Kamantsev, S. V.

2018-01-01

The critical points of steel 75Kh3MF and the temperature of the start of martensitic transformation are determined by a dilatometric method. The thermokinetic and isothermal diagrams of decomposition of supercooled austenite are plotted. The microstructure and microhardness of steel specimens cooled at different rates are studied. The kinetics of the occurrence of bainitic transformation in the steel is calculated using the Austin-Ricket equation.

Preliminary heat treatment of 4KhM2Fch die steel

International Nuclear Information System (INIS)

Leonidov, V.M.; Berezkin, Y.A.; Nikitenko, E.V.

1986-01-01

To improve the machinability and preparation of the structure for hardening, die steels are given a preliminary treatment which provides a reduction in hardness as a result of separation in the structure of the carbide and ferrite phases, coagulation of the carbides, and acquisition by them of a granular form and also the obtaining of fine grains and a uniform distribution of the structural constituents. The microstructure was evaluated after etching in 4% nital on an MIM-8M microscope. The 4KhM2Fch steel was given a preliminary heat treatment of normalize and anneal. It was concluded that for 4KhM2Fch steel a preliminary heat treatment of normalizing from 950 0 C with a hold of 1.5-2 h, annealing at 750-760 0 C with a hold of 2-3 h, cooling to the isothermal temperature of 670-680 0 C with a hold of 3-4 h, and further air cooling is recommended. The structure after such a heat is granular pearlite with a rating 1-2 and a hardness of 220-250 HB

Specific features of precipitation hardening of austenitic steels with various base. 2. Kinetics and mechanism of carbide precipitation

International Nuclear Information System (INIS)

Kositsyna, I.I.; Sagaradze, V.V.; Khakimova, O.N.

1997-01-01

Electron microscopic studies were carried out to determine the kinetics and mechanisms of precipitation hardening in Fe-Mn, Fe-Mn-Cr, Fe-Cr-Mn-N, Fe-Cr-Ni and Fe-Ni base stainless steels (45G20M2F2, 50Kh16G15N6M2F2, 45Kh18N10G10M2F2, 40Kh18Ni18M2F2, 45N26M2F2). The steels were heat treated under various conditions. It is revealed that in manganese steels the particles of vanadium carbide nucleate according to homogeneous mechanism at all aging temperatures (600-750 deg C). The presence of chromium in the matrix promotes the transition to heterogeneous mechanism of carbide nucleation and growth. With nickel content increasing the plasticity of precipitation hardened steels gets better due to more intense diffusion of atoms and vacancies to grain boundaries and, hence, the widening of near-boundary zones free of carbide particles

Depth profiling of {sup 14} N and {sup 20} Ne implantation into iron and steel using(p, gamma) reactions. Vol. 2

Energy Technology Data Exchange (ETDEWEB)

Wriekat, A; Haj-Abdellah, M [Physics Department, University of Jordan, Amman (Jordan)

1996-03-01

Depth profiles of {sup 14} N and {sup 20} Ne ions at 800 KeV implanted into iron and by steel samples have been measured by means of the proton induced {gamma}- ray emission (Pige) technique. The range, R, and range straggling, {Delta}R for these profiles were obtained and compared with theoretical calculations. The experimental results did show that pure iron retains more N and Ne than steel. 2 figs., 1 tab.

Successive carbon- and boron saturation of KhVG steel in powder mixtures

Energy Technology Data Exchange (ETDEWEB)

Alimov, Yu A; Gordienko, S I

1975-01-01

Method of successive saturation of KhVG steel with carbon and boron in powder mixtures is described. After carbonization of steel in a charcoal carburator at 930 deg C during 3 hrs a domain of equiaxial large grains is formed there the latter representing carbides of Fe/sub 3/C and (Fe, M)/sub 3/C. The increase of duration of carbonization up to 5 hrs and above results in formation of a cement grid greatly impairing the mechanical properties of the metal. Carbonization is followed by borating in powdered technical boron carbide at 900 deg C for 4 hrs which ensures formation on the sample surface of a borated layer with depth up to 65 mkm covering the carbonized zone. As followed from metallographic and x-ray structural analysis, the borated layer consists of boride needles with complex composition (Fe, Cr, Mn)B. Oil hardening of carbonized KhVG steel from 850 deg C and low-temperature tempering at 180 deg C for 1 hr results in formation in the main metal of martensite-carbide structure and, respectively, in the decrease of the microhardness gradient between the diffusion layers, as compared with borated KhVG steel. Operation tests of strengthened matrices of preforming machines under the conditions of application of dynamic pressing forces up to 1500 kg Fce/cm/sup 2/ demonstrated that the cyclical strength of carboborated coverings is 2.0-3.0 times higher than that of borated ones. The method of carboborating is recommended for strengthening the details of stamp and press tools.

Effect of zirconium on the structure and phase composition of steel 03Kh8SYu

International Nuclear Information System (INIS)

Tarzhumanova, V.A.; Ryabchenkov, A.V.; Shatunova, A.V.; Yoganova, S.A.

1986-01-01

Previously, the authors determined the optimum zirconium content providing retention of a fine-grained structure for steel 03Kh8SYu during high-temperature heating. It was suggested that this was caused by separation in the steel of intermetallic phase Fe 3 Zr. This paper presents results of further studies in this direction. X-ray analysis results for the anodic residues of the steels are presented. It can be seen that in steel without zirconium, carbides of the type M 23 C 6 and M 7 C 3 and aluminum nitride are present. On adding 0.05% Zr, zirconium nitride forms in addition to the existing aluminum nitride and carbides of the type M 7 C 3 . The authors also investigated the effect of zirconium on the tendency of the steel toward grain growth at higher temperature; they studied the structure of steel 03Kh8SYu with 0.61% Zr after soaking specimens for 100 h at 950-1100 C. Results are presented

Quality of the KhN73MBTYu alloy after electroslag remelting and vacuum arc remelting

International Nuclear Information System (INIS)

Shelgaeva, A.V.; Krichevets, M.I.; Shinkina, N.S.; Komissarov, A.I.

1978-01-01

The structure and properties of the heat-resisting KhN73MBTYu alloy are investigated after electroslag remelting (ESR) and vacuum arc (VAR) remelting in commercial furnaces. The complex investigations of the casted metal were carried out by modern methods along with the standard acceptance tests, and a number of service properties were determined. It is established that the ESR metal contains magnesium and has the reduced sulphur concentration; the alloy has more fine-grained structure at high isotropy of the properties at room and operating temperatures; higher endurance is achieved under reversal rotational bending; no laminated fractures are observed. According to the basic quality factors the ESR metal satisfies all requirements for the VAR metal. Due to exclusion of strippling of ESR electrodes and ingots the yield of steel forgings increases by 20-25% and the prime cost decreases in comparison with the industrial production of VAR metal

Influence of sulphur and phosphorus impurities on ductility of 25Kh2NMFA steel during forging

International Nuclear Information System (INIS)

Onishchenko, A.K.

1989-01-01

Using cylindrical samples of the 25Kh2NMFA steel with sulfur and phosphorus content in the range of 0.001-0.030%, tensile test with the rate of deformation 10 -3 s -1 at the temperatures of 800-1200 deg C has been conducted. Analysis of fracture foci and plasticity diagrams has shown, that to ensure ductility during forging and high mechanical properties, the content of sulfur and phosphorus impurities in the 25Kh2NMFA steel must not exceed 0.015%

Thermal creep and stress-affected precipitation of 20% cold-worked 316 stainless steel

International Nuclear Information System (INIS)

Puigh, R.J.; Lovell, A.J.; Garner, F.A.

1984-01-01

Measurements of the thermal creep of 20% cold-worked 316 stainless steel have been performed for temperatures from 593 to 760 0 C, stress levels as high as 138 MPa and exposure times as long as 15,000 hours. The creep strains exhibit a complex behavior arising from the combined action of true creep and stress-affected precipitation of intermetallic phases. The latter process is suspected to be altered by neutron irradiation. (orig.)

20,000-hour stress-corrosion cracking tests on ASTM A36 and A387-9 steels in simulated Hanford groundwater

International Nuclear Information System (INIS)

James, L.A.

1986-03-01

Modified WOL specimens were employed to evaluate the susceptibility of two candidate container materials, A36 and A387-9 steels, to SCC in simulated groundwater at 250 0 C. The test duration was 20,000 hours. Post-test measurements of specimen compliance were not possible because significant build-up of corrosion products and/or mineral deposits on the fracture faces prevented a linear relationship between load and displacement. Considerable load was ''lost'' due to time-independent plasticity, time-dependent deformation and crack-face wedging, but the amounts lost were comparable to similar short-term tests conducted earlier. A number of direct and indirect observations suggested that no crack extension occurred during the environmental exposure. One indirect observation, the initial pre-test compliance measurements, suggested a possibility of crack extension occurred, but it is believed that these measurements were in error because of the experimental test set-up used in the program

Hydrogen effect on mechanical properties and flake formation in the 10KhSND steel rolled plates

Energy Technology Data Exchange (ETDEWEB)

Muradova, R G; Zakharov, V A; Kuzin, A P; Gol' tsov, V A; Podgajskij, M S [Donetskij Politekhnicheskij Inst. (Ukrainian SSR); Donetskij Nauchno-Issledovatel' skij Inst. Chernoj Metallurgii (Ukrainian SSR))

1982-01-01

The effect of hydrogen on mechanical properties of the 10KhSND steel rolled plates during natural aging is studied. Optimum period of metal acceptance tests, which are advisable to conduct after 5-7 day natural aging of finished products, are found out. The technique is worked out and a safe hydrogen content to prevent flake formation in the 10KhSND steel is determined. It is shown that a safe hydrogen content is dependent on the experiment conditions (sample dimensions, conditions of cooling, and prehistory).

Hydrogen effect on mechanical properties and flake formation in the 10KhSND steel rolled plates

International Nuclear Information System (INIS)

Muradova, R.G.; Zakharov, V.A.; Kuzin, A.P.; Gol'tsov, V.A.; Podgajskij, M.S.

1982-01-01

The effect of hydrogen on mechanical properties of the 10KhSND steel rolled plates during natural aging is studied. Optimum period of metal acceptance tests, which are advisable to conduct after 5-7 day natural aging of finished products, are found out. The technique is worked out and a safe hydrogen content to prevent flake formation in the 10KhSND steel is determined. It is shown that a safe hydrogen content is dependent on the experiment conditions (sample dimensions, conditions of cooling, and prehistory)

Study of 16KhSN high strength steel in different structural states and under working conditions

International Nuclear Information System (INIS)

Skudnov, V.A.; Vorob'ev, I.A.; Kutyajkin, V.G.; Bugrov, Yu.V.

1985-01-01

A study was made on the effect of deformation degree (up to 60%) during reducing, drawing and heat treatment (annealing at 750 deg C), quenching from 930 deg C and tempering at 350 deg C) on strength, plasticity, hardening degree, notch sensitivity, density and elasticity characteristics of the steel. The effect of test temperature (from-196 up to 1000 deg C) on tensile strength and plasticity was studied as well. It was established that drawing and reducing of 16KhSN steel in annealed state with strain degrees of up to 60% results to increase of strength characteristics 1.7...2.3 times and decrease of plasticity characteristics by 15...23%, strain hardening coefficient - 2.2 times and the maximum strain energy - by 80 MJ/m 3 . Hardening heat treatment (quenching from 930 deg C+temperating at 350 deg C) affects on mechanical properties of 16KhSN steel in much the same way as cold working, but strength characteristics of heat-treated steel increase 2.6...3.6 times and the maximum strain energy grows by 640 MJ/m 3 . Systematic data on the effect of temperature (-196...1000 deg C) and tensile rate (4 mm/min...5m/s) on strength and plasticity of 16KhSN steel in annealed state were obtained

On the adsorption-induced fatigue of structural steels in the presence of alcohols

International Nuclear Information System (INIS)

Loboiko, V.I.; Karpenko, G.V.; Vasilenko, I.I.

1976-01-01

The purpose of the work was to study he effect of anhydrous alcohols on the cyclic fatigue of steels in the absence of contact of the alcohol with atmospheric moisture during the testing process. A vacuum was created in the operating space and then the vacuum annealing was carried out in a bath with the sample and through metal vacuum connection the bath was filled with anhydrous alcohol. Studies were made on several construction steels (20Kh, 40Kh, 50Kh, and ShKh15); steels 40Kh, 50Kh, and ShKh15 were quenched from 840-860 0 C in oil and then tempered at 200 0 C (2 h), steel 20Kh was studied in the as-received state. It was shown that with increase in the carbon content of steel with a martensite structure, the decrease in strength in the presence of anhydrous alcohol was greater than in dry air. Experiments showed that anhydrous alcohol causes an adsorption decrease in the strength both of samples with preliminarily formed cracks and V-shaped stress concentrators and of smooth samples. The greatest adsorption effect of alcohols in our case, as in static fatigue, was observed in samples with cracks. A dependence was shown between the length of the carbon chain and the fatigue limit. This dependence indicates the monotone nature of the decrease in the fatigue limit with transfer from methyl to butyl and then to octyl alcohol

Protective effect of KhOSP-10 inhibitor during corrosion, hydrogenadsorption and corrosion cracking of a steel in sulfuric acid

Energy Technology Data Exchange (ETDEWEB)

Mindyuk, A K; Svist, E I; Savitskaya, O P; Goyan, E B; Gopanenko, A N [AN Ukrainskoj SSR, Lvov. Fiziko-Mekhanicheskij Inst.

1975-01-01

The protective propeties of inhibitor KhOSP-10 in the time of corrosion and corrosive cracking of steel 40Kh are higher then those of inhibitors KPI-1, KI-1, I-I-V etc. Its ability to reduce steel hydrogenation is the same as in the case of KPI-1 inhibitor i.e. below that of KI-1. HCl additives enhance the efficiency of inhibitors KPI-1, KI-1, I-1-V etc. up to the protective ability of KhOSP-10. Kinetics of the electrode processes was estimated from polarization curves.

Stainless austenitic steels strengthened due to reversible phase transformations and by ageing

International Nuclear Information System (INIS)

Sagaradze, V.V.; Kositsyna, I.I.; Ozhiganov, A.V.

1981-01-01

The effect of the reversible phase transformations, consisting in the conduction of the direct and reverse martensite transformations and aging, during which the intermetallide γ'-phase of the composition Ni 3 Ti is formed, on the streng-thening of alloys in the Fe-Cr-Ni-Ti system is considered. Stainless austenitic steels Kh12N12T3 and Kh12N14T3, which acquire high mechanical properties: σsub(0.2)=685-785 MPa, σsub(B)=1275 MPa, delta >= 20%, as a result of reversible phase transformations and aging, are suggested. After the reversible phase transformations and ageing the steels possess a high resistance to γ-α-transformation during cold treatment [ru

Cooling rate and microstructure of surface layers of 5KhNM steel, machined by electroerosion method

International Nuclear Information System (INIS)

Foteev, N.K.; Ploshkin, V.V.; Lyakishev, V.A.; Shirokov, S.V.

1982-01-01

The cooling rate and microstructure of surface layers of steel 5KhNM machined by electroerosion method have been studied. It is shown that the difference in heating rate of the surface layers with electric discharge over the 5KhNM steel samples depth results in the intensive size reduction of the microstructure. In the surface layer alongside with martensite residual austenite is present, the lattice period of which increases with the increase of pulse duration, carbide phase of complex composition appears, and concentrational heterogeneity in alloying elements (except carbon) is absent

Cooling rate and microstructure of surface layers of 5KhNM steel, machined by electroerosion method

Energy Technology Data Exchange (ETDEWEB)

Foteev, N.K.; Ploshkin, V.V.; Lyakishev, V.A.; Shirokov, S.V.

1982-01-01

The cooling rate and microstructure of surface layers of steel 5KhNM machined by electroerosion method have been studied. It is shown that the difference in heating rate of the surface layers with electric discharge over the 5KhNM steel samples depth results in the intensive size reduction of the microstructure. In the surface layer alongside with martensite residual austenite is present, the lattice period of which increases with the increase of pulse duration, carbide phase of complex composition appears, and concentrational heterogeneity in alloying elements (except carbon) is absent.

Choice of corrosion-resistant metal for fluotitanic acid

International Nuclear Information System (INIS)

Reingeverts, M.D.; Lapchenko, E.P.; Semenyuk, E.Y.

1986-01-01

The authors investigate the corrosion and anodic behavior of steels 12Kh18N10T, 08Kh21N6M2T, and 06KhN28MDT, nickel, and molybdenum in 10-40% naturally aerated solutions of H 2 TiF 6 at 20 and 50 degrees C. The authors found that in solutions of fluotitanic acid, as also in tetrafluoroboric and hydrofluoric acids, the most stable alloys are chromium-nickel-molybdenum alloy of type 06KhN28MDT and (for acid concentrations above 20%) copper-nickel-alloys of the monel metal type. Steels 12Kh18N10T and 08Kh21N6M2T can be used in acid concentrations of less than 10% and temperatures up to 20 degrees C with anodic protection

Irradiation and annealing behavior of 15Kh2MFA reactor pressure vessel steel

International Nuclear Information System (INIS)

Popp, K.; Bergmann, U.; Bergner, F.; Hampe, E.; Leonhardt, W.D.; Schuetzler, H.P.; Viehrig, H.W.

1992-01-01

This work deals with the mechanical properties of RPV steels used WWER-440. The materials under investigation were a forging (base metal 15Kh2MFA) and the corresponding weld. Charpy V-notch specimens and tensile test specimens were irradiated in the WWER-2 Rheinsberg at about 270 C up to the two neutron fluence levels of 4 x 10 18 and 5 x 10 19 n/cm 2 (E>1MeV). Post-irradiation annealing heat treatments were performed, among others a 475 C/152 h treatment of technical interest. (orig.)

Quality of austenite chrome-nickel steel made by gas-oxygen refining

International Nuclear Information System (INIS)

Fel'dgandler, Eh.G.; Levin, F.L.; Moshkevich, E.A.; Shifrin, Eh.V.; Movshovich, V.S.; Pargamonov, E.A.

1991-01-01

Properties and structure were investigated of austenitic 03Kh18N11 and 08KhN10T steels melted at gas oxygen refining aggregates. It was established that mechanical and corrosion properties of rolling of such steels were in agreement with standard properties of metal of open melting. Sheet 08Kh18N10T steel has the level of strength and plasticity regulated for 12Kh18N10T steel. As steel of 08Kh18N10T holds the complex of high mechanical and corrosion properties, 08Kh18N10T is recommended to be replace by 12Kh18N10T with the aim of decrease of titanium usage and increase of process efficiency

What does a worm want with 20,000 genes?

OpenAIRE

Hodgkin, Jonathan

2001-01-01

The number of genes predicted for the Caenorhabditis elegans genome is remarkably high: approximately 20,000, if both protein-coding and RNA-coding genes are counted. This article discusses possible explanations for such a high value.

Coarsening of (Fe, Cr)23C6 carbide phase on the tempering of 14Kh17N2 chromium-nickel steel

International Nuclear Information System (INIS)

Psarev, V.I.

2002-01-01

Paper lists the results of computer analysis of distribution according to sizes (Fe, Cr) 23 C 6 microparticles resulting from 14Kh17N2 steel tempering under 700 Deg C. Data were obtained at the maximum beneficial magnification of a light microscope. The mentioned curves of distribution densities are characterized by more reliable run from most permissible sizes of dispersed particles. Application of general rules of distributions and of previously elaborated procedure to identify experimental histograms with theoretical distributions enables to derive valuable information on dynamics of coarsening of a disperse phase in this case, as well [ru

Influence of chemical heterogeneity of solid solutions on brittleness in chromium steels

International Nuclear Information System (INIS)

Madyanov, S.A.; Sedov, V.K.; Apaev, B.A.

1985-01-01

The role of chemical heterogeneity of solid solutions in formation of mechanical properties of Kh09, Kh15, Kh20, Kh19N2G5T chromium steels has been investigated. It is established that besides the known regioA of chemical heterogeneity in the vicinity of 475 deg C exists a high-temperature region (1000-1050 deg C), where maximum heteroge=- neity of chromium distribution in solid solution, is observed. Both types of chemical heterogeneity cause essential hardening of alloys, which becomes apparent in abrupt change of capability to microplastic deformation The mechanism of occurrence of the given temper brittleness consists in carbon diffusion into microvolunes enriched in carbide-forming elements

On the protective effect of KhOSP-10 inhibitor during corrosion, hydrogenadsorption and corrosion cracking of a steel in sulfuric acid

International Nuclear Information System (INIS)

Mindyuk, A.K.; Svist, E.I.; Savitskaya, O.P.; Goyan, E.B.; Gopanenko, A.N.

1975-01-01

The protective propeties of inhibitor KhOSP-10 in the time of corrosion and corrosive cracking of steel 40Kh are higher then those of inhibitors KPI-1, KI-1, I-I-V etc. Its ability to reduce steel hydrogenation is the same as in the case of KPI-1 inhibitor i.e. below that of KI-1. HCl additives enhance the efficiency of inhibitors KPI-1, KI-1, I-1-V etc. up to the protective ability of KhOSP-10. Kinetics of the electrode processes was estimated from polarization curves

Long-term strength and allowable stresses of grade 10Kh9MFB and X10CrMoVNb9-1 (T91/P91) chromium heat-resistant steels

Science.gov (United States)

Skorobogatykh, V. N.; Danyushevskiy, I. A.; Schenkova, I. A.; Prudnikov, D. A.

2015-04-01

Currently, grade X10CrMoVNb9-1 (T91, P91) and 10Kh9MFB (10Kh9MFB-Sh) chromium steels are widely applied in equipment manufacturing for thermal power plants in Russia and abroad. Compilation and comparison of tensile, impact, and long-term strength tests results accumulated for many years of investigations of foreign grade X10CrMoVNb9-1, T91, P91, and domestic grade 10Kh9MFB (10Kh9MFB-Sh) steels is carried out. The property identity of metals investigated is established. High strength and plastic properties of steels, from which pipes and other products are made, for operation under creep conditions are confirmed. Design characteristics of long-term strength on the basis of tests with more than one million of hour-samples are determined ( and at temperatures of 500-650°C). The table of recommended allowable stresses for grade 10Kh9MFB, 10Kh9MFB-SH, X10CrMoVNb9-1, T91, and P91 steels is developed. The long-time properties of pipe welded joints of grade 10Kh9MFB+10Kh9MFB, 10Kh9MFB-Sh+10Kh9MFB-Sh, X10CrMoVNb9-1+X10CrMoVNb9-1, P91+P91, T91+T91, 10Kh9MFB (10Kh9MFB-Sh)+X10CrMoVNb9-1(T/P91) steels is researched. The welded joint reduction factor is experimentally determined.

Fabrication of welded pipes of the KhN45Yu alloy

International Nuclear Information System (INIS)

Lyapunov, A.I.; Krichevskij, E.M.; L'vov, V.N.; Kozlov, N.N.; Kireeva, T.S.

1977-01-01

A highly heat-resistant KhN45Yu (EP 747) alloy has been developed; the alloy is designed to withstand prolonged service in the temperature range of 1000-1300 deg C, or short-term service at 1300-1400 deg C. The satisfactory ductility and good weldability of the alloy have made it possible to obtain sheets and pipes (32 x 2.0 mm) by argon arc welding. The ductility of pipes from EP 747 alloy exceeds that of pipes from KhN78T (EI 435) alloy by 5.10%, the strength being approximately equal. In regard to strength the welded joint differs little from the base metal. The ductility characteristics up to 900 deg C are also equal, since failure occurs in the base metal. At higher temperatures the welded joint fails in the metal of the weld, and its ductility drops sharply. The grain size of the base metal corresponds to No. 3-4. The welded joint has a cast structure with a grain size larger than No. 1, but its ductility characteristics are satisfactory. This structure ensures an increased long-term strength of the material at 1000-1200 deg C

Corrosion of steels in molten gallium (Ga), tin (Sn) and tin lithium alloy (Sn–20Li)

Energy Technology Data Exchange (ETDEWEB)

Kondo, Masatoshi, E-mail: kondo.masatoshi@nr.titech.ac.jp [Research Laboratory for Nuclear Reactors, Tokyo Institute of Technology, 2-12-1 O-okayama, Meguro-ku, Tokyo 152-8550 (Japan); Ishii, Masaomi [Department of Nuclear Engineering, School of Engineering, Tokai University, 4-1-1 Kitakaname, Hiratsuka-shi, Kanagawa 259-1292 (Japan); Muroga, Takeo [Department of Helical Plasma Research, National Institute for Fusion Science, Toki, Gifu 502-5292 (Japan)

2015-10-15

Graphical abstract: Corrosion of RAFM steel, JLF-1, in liquid Sn–20Li was caused by the formation of Fe-Sn alloyed layer. - Highlights: • The corrosion tests were performed for the reduced activation ferritic martensitic steel JLF-1 and the austenitic steel SUS316 in liquid Ga, Sn and Sn-20Li at 873 K up to 750 h. • The weight loss of the specimens exposed to liquid Ga, Sn and Sn-20Li was evaluated. • The corrosion of the steels in liquid Ga was caused by the alloying reaction between Ga and Fe on the steel surface. • The corrosion of the steels in liquid Sn was caused by the alloying reaction between Sn and Fe on the steel surface. • The corrosion of the steels in liquid Sn-20Li was caused by the formation of the Fe-Sn alloyed layer and the diffusion of Sn and Li into the steel matrix. - Abstract: The compatibility of steels in liquid gallium (Ga), tin (Sn) and tin lithium alloy (Sn–20Li) was investigated by means of static corrosion tests. The corrosion tests were performed for reduced activation ferritic martensitic steel JLF-1 (JOYO-HEAT, Fe–9Cr–2W–0.1C) and austenitic steel SUS316 (Fe–18Cr–12Ni–2Mo). The test temperature was 873 K, and the exposure time was 250 and 750 h. The corrosion of these steels in liquid Ga, Sn and Sn–20Li alloy was commonly caused by the formation of a reaction layer and the dissolution of the steel elements into the melts. The reaction layer formed in liquid Ga was identified as Fe{sub 3}Ga from the results of metallurgical analysis and the phase diagram. The growth rate of the reaction layer on the JLF-1 steel showed a parabolic rate law, and this trend indicated that the corrosion could be controlled by the diffusion process through the layer. The reaction layer formed in liquid Sn and Sn–20Li was identified as FeSn. The growth rate had a linear function with exposure time. The corrosion in Sn and Sn–20Li could be controlled by the interface reaction on the layer. The growth rate of the layer formed

Corrosion of steels in molten gallium (Ga), tin (Sn) and tin lithium alloy (Sn–20Li)

International Nuclear Information System (INIS)

Kondo, Masatoshi; Ishii, Masaomi; Muroga, Takeo

2015-01-01

Graphical abstract: Corrosion of RAFM steel, JLF-1, in liquid Sn–20Li was caused by the formation of Fe-Sn alloyed layer. - Highlights: • The corrosion tests were performed for the reduced activation ferritic martensitic steel JLF-1 and the austenitic steel SUS316 in liquid Ga, Sn and Sn-20Li at 873 K up to 750 h. • The weight loss of the specimens exposed to liquid Ga, Sn and Sn-20Li was evaluated. • The corrosion of the steels in liquid Ga was caused by the alloying reaction between Ga and Fe on the steel surface. • The corrosion of the steels in liquid Sn was caused by the alloying reaction between Sn and Fe on the steel surface. • The corrosion of the steels in liquid Sn-20Li was caused by the formation of the Fe-Sn alloyed layer and the diffusion of Sn and Li into the steel matrix. - Abstract: The compatibility of steels in liquid gallium (Ga), tin (Sn) and tin lithium alloy (Sn–20Li) was investigated by means of static corrosion tests. The corrosion tests were performed for reduced activation ferritic martensitic steel JLF-1 (JOYO-HEAT, Fe–9Cr–2W–0.1C) and austenitic steel SUS316 (Fe–18Cr–12Ni–2Mo). The test temperature was 873 K, and the exposure time was 250 and 750 h. The corrosion of these steels in liquid Ga, Sn and Sn–20Li alloy was commonly caused by the formation of a reaction layer and the dissolution of the steel elements into the melts. The reaction layer formed in liquid Ga was identified as Fe 3 Ga from the results of metallurgical analysis and the phase diagram. The growth rate of the reaction layer on the JLF-1 steel showed a parabolic rate law, and this trend indicated that the corrosion could be controlled by the diffusion process through the layer. The reaction layer formed in liquid Sn and Sn–20Li was identified as FeSn. The growth rate had a linear function with exposure time. The corrosion in Sn and Sn–20Li could be controlled by the interface reaction on the layer. The growth rate of the layer formed in

Creep damage development in welded X20 and P91

Energy Technology Data Exchange (ETDEWEB)

Brett, Steve; Holmstrom, Stefan; Hald, John; Borg, Ulrik; Aakjaer Jensen, Soeren; Vulpen, Rijk Van; Degnan, Craig; Vinter Dahl, Kristian; Vilhelmsen, Tommy

2011-03-15

The Martensitic steel X20CrMoV121 (hereinafter called X20) and the modified 9Cr1Mo steel (hereinafter called P91) have been used for a number of years in high temperature applications since they posses superior creep strength compared to low alloyed steels. Due to the simple fact that very few failures were observed, almost no knowledge as to the evolution of creep damage in welds were available despite long operation times exceeding well over 100.000 hours. It has been suggested that X20 will develop creep damage in a different manner compared to low alloyed steel, i.e damage initiation should be slow followed by accelerated growth. The research work presented in this report included systematic investigations of the first components of X20, which has developed creep during long-term operation. All of the investigated components showed creep damage evolution similar to low alloy steels

Defect accumulation in welded joints of 12Kh1MF steel steam pipelines during creep

International Nuclear Information System (INIS)

Anokhov, A.E.; Alekhova, I.A.

1982-01-01

Technique for investigation of micropore accumulation in 12Kh1MF steel welded joints is proposed. The micropore density in different zones of welded joints in non-uniform. It is shown that failure localization in welded joint in the softening zone during the creep takes place due to the micropore priority accumulation in this zone. It is found out that accumulation of residual deformations in different zones of 12Kh1MF welded joints under creep runs more uniformly as the level of working stresses decreases and test duration increases

Close toleranoe forging of chromium steel blades for powerful steam turbines

International Nuclear Information System (INIS)

Shastin, Eh.G.; Kositskij, Yu.N.; Lyubchits, G.A.

1989-01-01

Work on simulating technological process on die-forging hammer was performed in order to reduce the preparation period bringing technology of close tolerance forging of turbine blades to a commercial level. A special attention was paid to development of accurate forming of forgings of 20Kh13Sh, 12Kh13 and 15Kh11MFSh steels on screw presses with nominal effort equal to 80 and 144 MN

Coulomb dissociation of N 20,21

OpenAIRE

Röder, Marko; Adachi, Tatsuya; Aksyutina, Yulia; Alcantara, Juan; Altstadt, Sebastian; Alvarez-Pol, Hector; Ashwood, Nicholas; Atar, Leyla; Aumann, Thomas; Avdeichikov, Vladimir; Barr, M.; Beceiro, Saul; Bemmerer, Daniel; Benlliure, Jose; Bertulani, Carlos

2016-01-01

Neutron-rich light nuclei and their reactions play an important role in the creation of chemical elements. Here, data from a Coulomb dissociation experiment on N20,21 are reported. Relativistic N20,21 ions impinged on a lead target and the Coulomb dissociation cross section was determined in a kinematically complete experiment. Using the detailed balance theorem, the N19(n,γ)N20 and N20(n,γ)N21 excitation functions and thermonuclear reaction rates have been determined. The N19(n,γ)N20 rate is...

Effect of preliminary neutron irradiation on helium blistering of 0Kh16N15M3B steel

International Nuclear Information System (INIS)

Chernov, I.I.; Kalin, B.A.; Skorov, D.M.; Shishkin, G.N.; Ivanov, M.V.

1982-01-01

The method of electron microscopy has been applied to investigate the effect of preliminary neutron irradiation on the OKh16N15M3B steel blistering under irradiation by 20 keV helium ions with (1-10)x10 21 ion/m 2 doses at the temperature below 373 K. It is shown that neutron irradiation shifts critical doses of blister formation and intense scaling towards higher doses. But after the incubation period the erosion of steel preliminary neutron irradiated grows with the increase of helium ion dose above 7x10 21 ion/m 2 . Short-term heating of neutron irradiated samples during 15 min at 1173 K does not practically affect the beginning of intense scaling of the surface

Superheat effect on bainite steel hardenability

International Nuclear Information System (INIS)

Kubachek, V.V.; Sklyuev, P.V.

1978-01-01

The bainite hardenability of 34KhN1M and 35 KhN1M2Ph steels has been investigated by the end-face hardening technique. It is established that, as the temperature of austenitization rises from 900 to 1280 deg C, the temperature of bainite transformation increases and bainite hardenability of the steels falls off. A repeated slow heating to 900 deg C of previously overheated 34KhN1M steel breaks up grain, lowers the temperature of the bainite transformation and raises the hardenability to values obtained with ordinary hardening from 900 deg C. A similar heating of previously overheated 35KhN1M2Ph steel is accompanied by restoration of initial coarse grains and maintenance of both the elevated bainite transformation temperature and to lower hardenability corresponding to hardening from the temperature of previous overheating

Changes in structure and phase composition of chromium diffusion layer on stainless steels after long annealing

International Nuclear Information System (INIS)

Knyazev, E.V.; Voshedchenko, B.M.; Voskresenskij, Yu.A.

1985-01-01

A study was made on the effect of elevated temperatures UU and long holdings at heat on structure, phase composition and properties of chromium diffusion layer on austenitic chromium-nickel stainless steels 10Kh18N10TVD, 10Kh15N30M4B, 10Kh11N23T3MR, 10Kh21N28V6M3. The following mechanism of processes taking place in diffusion chromium layer is presented. The steady drop of chromium concentrations is observed after diffusion saturation. Chromium redistribution related with system transformation to more equilibrium state and simultaneous decarburization of steel surfaces takes place in diffusion layers of 10Kh15N30M4B and 10Kh21N28V6M3 steels after annealing at different temperatures and holdings at heat. Decarburization of steel surface layers is practically excluded in diffusion layers of 10Kh18N10T-VD and 10Kh11N23T3MR steels. Diffusion chromium-saturated layer stays effective only on 10Kh18N10T-VD and 10Kh11N23T3MR steels on heating up to 1000 deq C with holding up to 250 h

Cooling intensification during quenching of power plant components - the way to increase reliability

International Nuclear Information System (INIS)

Borisov, I.A.

1989-01-01

To enchance the complex of mechanical properties and to increase operation time of large components of power facilities, regimes of accelerated cooling are developed. Results of heat treatment with accelerated cooling of turbine rotor of steel 26KhN3M2FAA, disks of turbine welded rotor of steel 20KhN2MFAA, components of steel 35KhN3MFA, are given. Special steels with carbon content less than 0.30% for details of power machine-building are developed

Effect of preliminary heat treatment on phase transformations and properties of the Kh15N5D2T (VNS-2) steel

International Nuclear Information System (INIS)

Madyanov, S.A.; Voronenko, B.I.; Makhnev, E.S.

1978-01-01

It is shown that preliminary heat treatment has a significant effect on the α→γ transformation kinetics, the quantity of residual austenite, the grain size and mechanical properties of the Kh15N5D2T steel after final heat treatment. The preliminary heat treatment regimes leading to the increase of the quantity of residual austenite and to grain refining increase the work of crack propagation in the finally strengthened state. The optimum properties were obtained after threefold preliminary tempering for 1h at 650 deg C. An approximately constant relation of α- and γ-phases (approximately 50%) is observed at 625 deg C irrespective of the investigated regimes of preliminary heat treatment

Investigation of thermal fatigue of chromium-molybdenum steels, used for calcining and agglomeration constructions

International Nuclear Information System (INIS)

Sinyavskij, D.P.; Gorkalo, A.P.

1979-01-01

The technique for investigating thermal fatigue of materials is described. The data on sample stress deformed state and current temperature values are taken from the local volume of the material studied. Results of investigating thermal fatigue of the 15KhMl and 20KhMl steels are presented

Influence of quantity of non-martensite products of transformation on resistance to fracture of improving structural steel

International Nuclear Information System (INIS)

Gulyaev, A.P.; Golovanenko, Yu.S.; Zikeev, V.N.

1978-01-01

18KhNMFA, low-carbon, alloyed steel and 42KhMFA medium-carbon, alloyed steel have been examined. For the purpose of obtaining different structures in hardening the steel, different cooling rates, different temperatures and isothermal holding times are applied. The following has been shown: on tempering to the same hardness (HV 300), the presence of non-martensite structures in hardened state does not practically influence the standard mechanical properties of steel (sigmasub(B), sigmasub(0.2), delta, PSI). The resistance of steel to the brittle failure is enhanced by the uniform, fine-disperse distribution of the carbide phase in the structure of lower bainite (up to 80 % bainite in martensite for 42KhMF steel to be improved), as well as strongly fragmented packages of rack martensite-bainite (up to 50 % lower bainite in martensite of 18KhNMFA steel). The formation of the upper bainite in the structure of the hardened steels 18KhNMFA and 42KhMF results on tempering in the formation of coarse, non-uniform, branched carbide inclusions, and this, in its turn, leads to raising the cold-shortness threshold and to lowering the amount of work as required for propagation of a crack. The presence of ferritic-pearlitic structures in the structural steels hardened to martensite and bainite results in reducing the resistance of steel to the brittle failure; the presence of every 10 % ferritic-pearlitic component in martensite of the structural steels 18KhNMFA and 42KhMFA to be thermally improved, raises T 50 by 8 deg and 20 deg C, respectively

Extended high-frequency audiometry (9,000-20,000 Hz). Usefulness in audiological diagnosis.

Science.gov (United States)

Rodríguez Valiente, Antonio; Roldán Fidalgo, Amaya; Villarreal, Ithzel M; García Berrocal, José R

2016-01-01

Early detection and appropriate treatment of hearing loss are essential to minimise the consequences of hearing loss. In addition to conventional audiometry (125-8,000 Hz), extended high-frequency audiometry (9,000-20,000 Hz) is available. This type of audiometry may be useful in early diagnosis of hearing loss in certain conditions, such as the ototoxic effect of cisplatin-based treatment, noise exposure or oral misunderstanding, especially in noisy environments. Eleven examples are shown in which extended high-frequency audiometry has been useful in early detection of hearing loss, despite the subject having a normal conventional audiometry. The goal of the present paper was to highlight the importance of the extended high-frequency audiometry examination for it to become a standard tool in routine audiological examinations. Copyright © 2015 Elsevier España, S.L.U. y Sociedad Española de Otorrinolaringología y Patología Cérvico-Facial. All rights reserved.

Relationships of quenching stresses to structural transformations in steel

International Nuclear Information System (INIS)

Loshkarev, V.E.

1985-01-01

Technique for accountancy of the effect of stresses on structural transformations in steel when solving problems of thermoplasticity is suggested. It is revealed on the basis of the conducted calculations that accountancy of interrelation of stressed and structural states of 20Kh2MF steel essentially affects forecasting of results of quenching

Manufacture of rings of 08Kh18N10T sheet for internal structures of WWER type reactors

International Nuclear Information System (INIS)

Fojta, A.; Nitka, B.

1984-01-01

Technology is presented of the manufacture of rings for the jacket, shaft, core catcher and shaft bottom of WWER-440 reactors produced by Vitkovice Steel Works. The rings are manufactured from sheets of austenitic steel 08Kh18N10T. The materials and technology problems are discussed of sheet production, ring welding technology and annealing following welding. The plastic properties are assessed of the welded joints and problems are outlined of ring production for WWER-1000 reactors. (B.S.)

Influence of prolonged service of steam turbines on the properties of materials of rotor and vessel components

International Nuclear Information System (INIS)

Anfimov, V.M.; Artamonov, V.V.; Chizhik, T.A.

1984-01-01

The structure and mechanical properties of steam turbine elements of 25Kh1MF, 25Kh1M1FA (rotors), 15Kh1M1FL (vessel components) steels have been investigated both in initial state and after 200 000 h operation. The structure stability and phase composition of rotor steels providing conservation of heat resistance at a required level was established. Examination of vessel components showed a decrease in the yield strength by 15-20% and durability - by 10% as compared to initial ones. The conclusion on a possible prolongation of the steam turbine service life to 200 000 h is drawn. The nominal service life equals 100 000 h

Influence of structure and properties of tubular billets of the 12 Kh 18N10T steel on deformability of tubes at cold-rolling mills

International Nuclear Information System (INIS)

Vil'yams, O.S.; Bol'shova, N.M.; Olejnik, O.V.; Velikotnaya, E.S.

1979-01-01

Metallographic analysis of the defects of the ''oblique cracks'' type on the surface of hot-rolled tubes of the 12Kh18N10T steel has been carried out. Recommended is the complex of mechanical properties and the structure factors (grain size) of conversion hot-rolled tubes, providing the combination of ductility and high rapture strength during rolling at pilger mills. At a grain size not coarser than number 5, a billet must have σsub(T) 5 >=40 %. Hot-rolled coarse-grained billet is not recommended for warm rolng because of high strain hardening

Steel corrosion in tributyl phosphate in the presence of water and ethyl mercaptan

International Nuclear Information System (INIS)

Pischik, L.M.; Tsinman, A.I.

1979-01-01

Studied is the corrosion of steels St3, 15Kh5M, 08Kh13, 10Kh14G14N4T, 08Kh18G8N2T, 10Kh17N13M2T in TBP, in mixtures of TBP with ethyl mercaptan (EM) and two-phase systems TBP-water and TBP-water-EM at 50-150 deg. In pure TBP St3 corrosion rate is low even at 150 deg. In the presence of water St 3 strongly corrodes at above 50 deg temperature in organic and water layers and also in gas phase. The steel-08Kh18G8N2T at 90 deg in acid TBP is passive and its corrosion rate is lower than 0.01 mm/year. In identical conditions the resistance of stainless steels increases together with chromium content but in TBP with acid number 100 and above at 150 deg all tested steels including steel-10Kh17N13M2T are slightly resistant. Thus, even in absence of corrosion active additions of EM the mixture of TBP-water at higher temperature is agressive in relation not only to carbon steel but also to stainless steels

Neutron irradiation embrittlement of reactor pressure vessel steel 20 MnMoNi55 weld

International Nuclear Information System (INIS)

Ghoneim, M.M.

1987-05-01

The effect of neutron irradiation on the mechanical and fracture properties of an 'improved' 20 MnMoNi 55 Pressure Vessel Steel (PVS) weld was investigated. In addition to very low residual element content, especially Cu (0.035 wt.%), and relatively higher Ni content (0.9 wt.%), this steel has higher strength (30% more) than the steels used currently in nuclear reactor pressure vessels. The material was irradiated to 3.5x10 19 and 7x10 19 n/cm 2 (E > 1 Mev) at 290 0 C and 2.5x10 19 n/cm 2 (E > 1 MeV) at 160 0 C in FRJ-1 and FRJ-2 research reactors at KFA, Juelich, F.R.G. Test methods used in the evaluation included instrumented impact testing of standard and precracked Charpy specimens, tensile, and fracture toughness testing. Instrumented impact testing provided load and energy vs. time (deflection) data in addition to energy absorption data. The results indicated that the investigated high strength improved steel is more resistant to irradiation induced embrittlement than conventional PVSs. (orig./IHOE)

Experimental verification of the statistical theories of scaling factor effect in fatigue fracture of steel

International Nuclear Information System (INIS)

Svistun, R.P.; Babej, Yu.I.; Tkachenko, N.N.

1976-01-01

Statistical theories of the scale effect in the fatigue failure of 40KH18N9T, 10 and 20 steels have been verified. The theories are shown to be not invariably suitable for a satisfactory exlanation of the fatigue strength of the samples with respect to their dimensions. One of the main reasons for displaying the scale effect in the process of steel fatigue is the sample self-heating, i.e. a temperature factor which in many cases overlaps a statistical one

Experimental verification of the statistical theories of scaling factor effect in fatigue fracture of steel

Energy Technology Data Exchange (ETDEWEB)

Svistun, R P; Babei, Yu I; Tkachenko, N N [AN Ukrainskoj SSR, Lvov. Fiziko-Mekhanicheskij Inst.; L' vovskij Lesotekhnicheskij Inst. (Ukrainian SSR))

1976-01-01

Statistical theories of the scale effect in the fatigue failure of 40KH18N9T, 10 and 20 steels have been verified. The theories are shown to be not invariably suitable for a satisfactory exlanation of the fatigue strength of the samples with respect to their dimensions. One of the main reasons for displaying the scale effect in the process of steel fatigue is the sample self-heating, i.e. a temperature factor which in many cases overlaps a statistical one.

Influence of Copper on the Hot Ductility of 20CrMnTi Steel

Science.gov (United States)

Peng, Hong-bing; Chen, Wei-qing; Chen, Lie; Guo, Dong

2015-02-01

The hot ductility of 20CrMnTi steel with x% copper (x = 0, 0.34) was investigated. Results show that copper can reduce its hot ductility, but there is no significant copper-segregation at the boundary tested by EPMA. The average copper content at grain boundaries and substrate is 0.352% and 0.318% respectively in steel containing 0.34% copper tensile-tested at 950 °C. The fracture morphology was examined with SEM and many small and shallow dimples were found on the fracture of steel with copper, and fine copper sulfide was found from carbon extraction replicas using TEM. Additionally, adding 0.34% copper caused an increase in the dynamic recrystallization temperature from 950 °C to 1000 °C, which indicates that copper can retard the dynamic recrystallization (DRX) of austenite. The detrimental influence of copper on hot ductility of 20CrMnTi steel is due mainly to the fine copper sulfide in the steel and its retarding the DRX.

characterization and weldability of plasma nitrided P/M martensitic stainless steel X 20 Cr Ni 172

International Nuclear Information System (INIS)

Abdel-Karim, R.A.; El-demellawy, M.A; Waheed, A.F.

2004-01-01

stainless steels are widely used in nuclear applications, as a construction material. in these applications stainless steels suffer from corrosion degradation due severe environment and operating conditions. improving the engineering properties of such material prolong the service life time.in the present study, powder metallurgy technique namely plasma rotating electrode process (PREP) was used to produce martensitic steel DIN X 20 Cr Ni 172 with 0.5 % N. this step was followed by hot isostatic pressing process (HIP) . the effect of N on the weldability of this steel has been investigated . this included microstructure characterization, hardness evaluation and ferrite content measurements. the results showed that the presence of high nitrogen content in this steel resulted in a pore free structure with improved the hardness across the welding area. A single phase with few precipitates was detected on the grain boundaries in the heat affected zone. the results were supplemented by x-ray diffraction patterns and EDAX analysis

Coulomb dissociation of N-20,N-21

NARCIS (Netherlands)

Roeder, Marko; Adachi, Tatsuya; Aksyutina, Yulia; Alcantara, Juan; Altstadt, Sebastian; Alvarez-Pol, Hector; Ashwood, Nicholas; Atar, Leyla; Aumann, Thomas; Avdeichikov, Vladimir; Barr, M.; Beceiro, Saul; Bemmerer, Daniel; Benlliure, Jose; Bertulani, Carlos; Boretzky, Konstanze; Borge, Maria J. G.; Burgunder, G.; Caamano, Manuel; Caesar, Christoph; Casarejos, Enrique; Catford, Wilton; Cederkall, Joakim; Chakraborty, S.; Chartier, Marielle; Chulkov, Leonid; Cortina-Gil, Dolores; Crespo, Raquel; Pramanik, Ushasi Datta; Diaz-Fernandez, Paloma; Dillmann, Iris; Elekes, Zoltan; Enders, Joachim; Ershova, Olga; Estrade, A.; Farinon, F.; Fraile, Luis M.; Freer, Martin; Freudenberger, M.; Fynbo, Hans; Galaviz, Daniel; Geissel, Hans; Gernhaeuser, Roman; Goebel, Kathrin; Kalantar-Nayestanaki, Nasser; Najafi, Mohammad Ali; Rigollet, Catherine; Stoica, V.; Streicher, Branislav; Van de Walle, J.

2016-01-01

Neutron-rich light nuclei and their reactions play an important role in the creation of chemical elements. Here, data from a Coulomb dissociation experiment on N-20,N-21 are reported. Relativistic N-20,N-21 ions impinged on a lead target and the Coulomb dissociation cross section was determined in a

On choice of tempered steels

International Nuclear Information System (INIS)

Govorov, A.A.; Pan'shin, I.F.; Rakhmanov, V.I.

1978-01-01

For the purpose of developing a graphical method for choosing structural steels, a change in the propagation work of a crack and in the critical temperature of brittleness of 40, 40Kh, 40KhN, and 40KhNM steels, was examined depending on the hardness after hardening and tempering. A diagram enabling to choose the grade of steel for making an article of known dimensions according to the preset values of its mechanical properties has been plotted. The developed selection scheme takes into account the hardenability of steels and the influence of the hardness after thermal treatment on the cold-shortness of steel

Strain ageing of the 15Kh2MFA steel at 500 and 550 deg C

International Nuclear Information System (INIS)

Maksimovich, G.G.; Azbukin, V.G.; Krylova, R.P.; Tretyak, I.Yu.; Bardachevskaya, T.V.

1978-01-01

The effect of ageing at high temperatures and under high stresses on strength and plasticity of the 15Kh2MFA steel has been studied. The steel was kept at 500 and at 550 deg C for 100, 1000 and 2500 hours without stress and under stress of 0.5 and 0.9 of the long-term strength limit (sigmasub(ls)). Ageing at 500 deg C without stress and under 0.5 sigmasub(ls) changed neither strength nor plasticity of the steel; under 0.9 sigmasub(ls) the strength somewhat decreased. Ageing at 550 deg C for 1000 hours resulted in an appreciable stress drop

Simulation of Microdamage and Evaluation of Remaining Life of Steam Conduit Components from New-Generation Refractory Steel 10Kh9MF-Sh

Science.gov (United States)

Gladshtein, V. I.

2018-03-01

The effects of microdamage on the remaining life of high-temperature components of steam conduits from high-chromium steel 10Kh9MF-Sh and low-alloy steel 12Kh1M1F are compared. To simulate the microdamage, specimens with a circular notch and different relative diameters are fabricated. Specimens with a notch simulating the highest degree of microdamage and smooth specimens are tested for long-term strength. The coefficient of the remaining life of a conduit is computed for the range of relative damage presenting practical interest.

Effect of melting technique on grain size and heat resistance of the 12Kh1MF steel

International Nuclear Information System (INIS)

Lanskaya, K.A.; Kulikova, L.V.; Butneva, N.I.

1978-01-01

Investigated are the 12Kh1MF steel melted in open-hearth and arc furnaces (deoxidation by aluminium in 1.0 kg/t quantity) and then subjected to electroslag melting. The size of an austenitic grain depends on the residual contents of nitrogen and aluminium in steel. The open-hearth metal subjected to electroslag melting and containing a small quantity of nitrogen (0.006%) and aluminium (0.013%) has coarse austenitic grains and higher heat resistance compared to the steel melted in an arc furnace and also sub ected to electroslag melting. The nitride analysis of steel is carried out

Hydrogen pick-up effect on the deformation characteristics of the 20 steel

International Nuclear Information System (INIS)

Steklov, O.I.; Perunov, B.Vs.; Krovyakova, V.M.

1977-01-01

An experiment aimed at ascertaining the possibility of using plasticity characteristis as a criterion of the resistance of a material to slow failure through hydrogenation is set up in a manner to permit an evaluation of the individual effects of mechanical stresses hydrogenation medium and their combined action upon the plasticity characteristics. It is shown that the variation of the rupturing load for hydrogenated specimens of grade 20 steel, held under load, takes place on the initial holding stage, after which the changes in the plasticity characteritics are immaterial. In consequence, the deformation characteristics allow no judgement to be made on the resistance to slow cracking of grade 20 steel due to hydrogenation

REVIVALISME PENDIDIKAN ISLAM AWAL ABAD 20 (STUDI KRITIS PEMBARUAN PENDIDIKAN ISLAM PERSPEKTIF KH. AHMAD DAHLAN

Directory of Open Access Journals (Sweden)

Zetty Azizatun Ni'mah

2016-05-01

Full Text Available The idea of Islamic educational reform in Indonesia began in the early twentieth century. This was caused by out of concerns Muslim intellectual leaders of the secular education system which implemented the Dutch East Indies and then has a negative impact on the condition of Islamic education in Indonesia. KH. Ahmad Dahlan is pioneer figure of Islamic educational reform in Indonesia. He is of leaders respond to the condition of Islamic education in Indonesia needs to be updated in terms of objectives, materials, methods and management. This article aims to analyze thoughts KH. Ahmad Dahlan. KH. Ahmad Dahlan reform of Islamic education as well as his correlation with the current education system. This issues is examined using research methods “library research” using written materials in the form of books, magazines, journals, articles and other literatures relevant to the discussion. For data analysis the authors use the approach of history, sociology and anthropology. The results of the research that has been conducted by the author suggests that the concept of Islamic education reform in perspective KH. Ahmad: the aim of Islamic education leads to increased economic, politic, social race with modernism education, the Qur’an and Hadits are direct material examined by leaving the classic are often assessed the traditionalists, Islamic education methods abandon traditional methods, the Islamic educational institutions organized under auspices of the Muhammadiyah organization with a model of organizational leadership. Educational issues such as character building, problem solving, integration of scientific and educational innovation are concepts of education offered by KH.Ahmad Dahlan which it is an attempt to anticipate the renewal of the times and the situation in the subsequent periods.

Preliminary tension effect on low-cycle fatigue of 40Kh13 steel in gaseous hydrogen

International Nuclear Information System (INIS)

Romaniv, A.N.

1984-01-01

Comparative bending tests of specimens deformed by tension at 65, 18 and 30% in hydrogen and vacuum were accomplished to reveal the effect of preliminary tension on low-cycle fatigue strength of 40Kh13 martensitic steel. It was found that small amounts of preliminary strains induced a considerable decrease in low-cycle durability in vacuum and hydrogen which was connected with developing defects arising at the early stages of plastic deformation. A rather high degree of preliminary tension promoted steel homogenization, hydrogen embrittlement decrease and service behaviour improvement

Bainite transformation and TRIP effect in 20Mn2SiVB steel

International Nuclear Information System (INIS)

Huo Yanqiu; Long Xiuhui; Zhou Zhenhua; Li Jianguo

2006-01-01

Transformation-induced plasticity (TRIP) steel is a relatively new type of automotive steel known for its combination of high-strength and high ductility which was developed in the 1990s. 20Mn2SiVB steel is a kind of TRIP steel with low-carbon and low-alloying contents and high-strength. Specimens of a tested 20Mn2SiVB steel austenitized at 920 deg. C and austempered at 420 deg. C in a salt bath at different time are investigated. The microstructure obtained is studied by means of optical microscopy, scanning electron microscopy and X-ray diffraction. The results show that bainitic ferrite precipitates at the boundary of the austenite first, and with the prolongation of the isothermal time, the amount of bainitic ferrite increase. Then the ferrite decollates the austenite grain and lath-shaped bainitic ferrite with little island-shaped austenite forms during the holding time. The microstructure contains carbide-free bainite, granular bainite, retained austenite and martensite in the process of bainite transformation. Tensile test of the different treated specimens indicates that a better comprehensive property can be gained after austenized at 920 deg. C following austempered at 420 deg. C for 5 min, a certain TRIP effect can be also obtained under this condition

Study of cast and thermo-mechanically strengthened chromium-nickel nitrogen-containing steel

International Nuclear Information System (INIS)

Prokoshkina, V.G.; Kaputkina, L.M.; Svyazhin, A.G.

2000-01-01

The effect of nitrogen on the structure and strength of corrosion-resistant chromium-nickel steels after thermal and thermomechanical treatment is studied. The 06Kh15N7AD and 07Kh15N7DAMB steels alloying by nitrogen was accomplished through the basic composition steels remelting in the molecular nitrogen atmosphere under the pressure of 0.1-2.5 MPa. The 02Kh15N5DAF and 05Kh15N5DAM steels ingots were obtained through melting in a plasma furnace under the nitrogen pressure of 0.4MPA. The high-temperature thermomechanical treatment (HTMT) was performed by rolling with preliminary blanks heating up to 1050 deg C and the rolling end temperature not below 950 deg C. It is shown, that the HTMT of the nitrogen-containing steels makes it possible to obtain strength characteristics by 1.5 times exceeding the properties of traditionally applicable corrosion-resistant steels, whereby sufficiently high plasticity of the nitrogen-containing steel is retained [ru

Effect of smelting method on the austenite grain size and properties of heat-resisting pearlitic steel

International Nuclear Information System (INIS)

Balakhovskaya, M.B.; Khusainova, N.A.; Davlyatova, L.N.

1975-01-01

Influence of smelting method on austenite grain size and properties of refractory perlite steel were studied. An opportunity was found to increase the steel refractoriness without deteriorating its other properties. The steel 12Kh1MF of electric or common open-hearth smelting was used. The dependence of kinetics of austenite grain growth on the smelting method was studied in the temperature range 950 deg - 1200 deg C with 1 hour exposure. The grain size of austenite in steel is supposedly determined by aluminium nitrides and vanadium carbides. In tests of normalized (kept for 20 minutes at 950-980 deg C) and tempered (kept for 3 hours at 730 deg C) transverse (tangential) pipe cross-section samples the electric steel had higher impact viscosity than the open-hearth metal. At working temperatures (540 deg -580 deg C) the difference in viscosity has its minimum. Viscosity of both steels 12Kh1MF begins to sharply decrease from 20 deg C. However, electric steel has rather high viscosity even at - 40 deg C, while the open-hearth one becomes brittle as early as at - 20 deg C. Long-term strength tests at 580 deg C under stresses 10-14 kG/mm 2 show that the coarse-grain steel is more refractory, i.e. time till fracture of open-hearth steel samples is twice as long as that of electric steel samples

Austenite strengthening and softening during hot deformation

International Nuclear Information System (INIS)

Tushinskij, L.I.; Vlasov, V.S.; Kazimirova, I.E.; Tokarev, A.O.

1981-01-01

Processes of formation of austenite structure of 20 and 12Kh18N10T steels during hot deformation and postdeformation isothermal holdings have been investigated by the methods of analysis of curves of hot deformation, high-temperature metallography and light microscopy. Deformation has been exercised by extention in vacuum with average 4x10 -2 s -1 rate. Deformation temperatures of steel 20 are 930 and 1000 deg C, of steel 12Kh18N10T - 1100 deg C. It is stated that dynamic recrystallization takes place in both investigated steels during hot deformation. In the carbonic steel it is developed by shifting sections of high-angular boundaries, flow stress in this case remains constant. Recrystallization is developed by subgrain coalescence in austenite steel, that brings about preservation of increased defect density in recrystallized volumes. As a result strengthening of steel is continued up to fracture during the increase of the deformation degree. Postdeformation weakening of 12Kh18N10T steel is slowed down as compared with weakening of carbonic steel [ru

Study of nitrogen solubility in multicomponent iron alloys at its pressure in gaseous phase up to 1000kPa

International Nuclear Information System (INIS)

Pomarin, Yu.M.; Grigorenko, G.M.; Latash, Yu.V.; Kanibolotskij, S.A.

1983-01-01

A facility in which metal is melted in a weighed state and nitrogen partical pressure during relting may be charge from 0 to 1000 kPa is developed to investigate nitrogen solubility is liquim metals and alloys. Investigation of nitrogen solubility was performed using samples of 03Kh25N5AM3 steel and Kh20N5, Kh20N10, Kh40N10, Kh40N20 alloys. Positive deflection of [N]=f(√Psub(Nsub(2))) dependence from the Henry law is shown to be observed in the Kh40N10 alloy in the 100-1000 kPa pressure range. In this case the vatue of positive deflection decreases with temperature growth and at T=2273 K nitrogen solubility in the alloy submits to the law of square root. An equation permitting to calculate nitrogen solubility in alloys of Fe-Cr-Ni and Fe-Cr-Mn systems in the 0 to 1000 kPa range of nitrogen partial pressures is obtained

Effect of Heat Treatment on the Structure and Properties of Die Steel 70Kh3G2FTR

Science.gov (United States)

Krylova, S. E.; Kletsova, O. A.; Gryzunov, V. I.; Fot, A. P.; Tavtilov, I. Sh.

2018-01-01

The effect of heat treatment parameters on the properties and structural and phase composition of a promising die steel 70Kh3G2FTR for hot deformation is studied. The temperature-and-stress state of a hammer die under a heat treatment is simulated.

Microstructure Evolution and Flow Stress Model of a 20Mn5 Hollow Steel Ingot during Hot Compression.

Science.gov (United States)

Liu, Min; Ma, Qing-Xian; Luo, Jian-Bin

2018-03-21

20Mn5 steel is widely used in the manufacture of heavy hydro-generator shaft due to its good performance of strength, toughness and wear resistance. However, the hot deformation and recrystallization behaviors of 20Mn5 steel compressed under high temperature were not studied. In this study, the hot compression experiments under temperatures of 850-1200 °C and strain rates of 0.01/s-1/s are conducted using Gleeble thermal and mechanical simulation machine. And the flow stress curves and microstructure after hot compression are obtained. Effects of temperature and strain rate on microstructure are analyzed. Based on the classical stress-dislocation relation and the kinetics of dynamic recrystallization, a two-stage constitutive model is developed to predict the flow stress of 20Mn5 steel. Comparisons between experimental flow stress and predicted flow stress show that the predicted flow stress values are in good agreement with the experimental flow stress values, which indicates that the proposed constitutive model is reliable and can be used for numerical simulation of hot forging of 20Mn5 hollow steel ingot.

Corrosion failure of a bolt made of the 25Kh1MF material

International Nuclear Information System (INIS)

Liska, V.; Cechova, D.; Velkoborsky, J.

1989-01-01

M36x4 bolts, of which there are 222 at each nuclear power plant unit, are made of the 25Kh1MF or 38KhN3MFA steel. They are located in an environment with elevated temperature, with damp air and with boric acid. Corrosion of these bolts is due to the rather poor metallurgical quality of the steel. No inadmissible inhomogeneities of the type of lines of inclusions occur in the bolt material produced by cold rolling but defects of the type of laps were found on the threads. It is suggested that if the cold rolling technology were obviated, corrosion failure of the bolts might not occur. (M.D.). 7 figs., 3 refs

Effect of smelting method on the austenite grain size and properties of heat-resisting pearlitic steel

Energy Technology Data Exchange (ETDEWEB)

Balakhovskaya, M B; Khusainova, N A; Davlyatova, L N [Vsesoyuznyj Nauchno-Issledovatel' skij Teplotekhnicheskij Inst., Moscow (USSR)

1975-12-01

Influence of smelting method on austenite grain size and properties of refractory perlite steel were studied. An opportunity was found to increase the steel refractoriness without deteriorating its other properties. The steel 12Kh1MF of electric or common open-hearth smelting was used. The dependence of kinetics of austenite grain growth on the smelting method was studied in the temperature range 950 deg - 1200 deg C with 1 hour exposure. The grain size of austenite in steel is supposedly determined by aluminium nitrides and vanadium carbides. In tests of normalized (kept for 20 minutes at 950-980 deg C) and tempered (kept for 3 hours at 730 deg C) transverse (tangential) pipe cross-section samples the electric steel had higher impact viscosity than the open-hearth metal. At working temperatures (540 deg -580 deg C) the difference in viscosity has its minimum. Viscosity of both steels 12Kh1MF begins to sharply decrease from 20 deg C. However, electric steel has rather high viscosity even at /sup -/40 deg C, while the open-hearth one becomes brittle as early as at /sup -/20 deg C. Long-term strength tests at 580 deg C under stresses 10-14 kG/mm/sup 2/ show that the coarse-grain steel is more refractory, i.e. time till fracture of open-hearth steel samples is twice as long as that of electric steel samples.

Corrosion resistance of chromium-nickel steel containing rare earths

International Nuclear Information System (INIS)

Asatiani, G.N.; Mandzhgaladze, S.N.; Tavadze, L.F.; Chuvatina, S.N.; Saginadze, D.I.

1983-01-01

Effect of additional out-of-furnace treatment with complex alloy (foundry alloy) calcite-silicon-magnesium-rare earth metal on corrosion resistance of the 03Kh18N20M3D3C3B steel has been studied. It is shown that introduction of low additions of rare earths improves its corrosion resistance improves its corrosion resistance in agressive media (in 70% - sulfuric acid) in the range of transition from active to passive state. Effect of additional introduction of rare earth metals is not considerable, if potential of steel corrosion is in the range of stable passive state (32% - sulfuric acid). Additional out-of-furnace treatment with complex foundry alloy, containing rare earth metals, provides a possibility to use a steel with a lower content of Cr, Ni, Mo, than in conventional acid-resistant steels in highly agressive media

Influence of creep ductility on creep-fatigue behaviour of 20%Cr/25%Ni/Nb stainless steel

International Nuclear Information System (INIS)

Gladwin, D.; Miller, D.A.

1985-01-01

The influence of creep ductility on creep-fatigue endurance of 20%Cr/25%Ni/Nb stainless steel has been examined. In order to induce different creep ductilities in the 20/25/Nb stainless steel, three different thermo-mechanical routes were employed. These resulted in a range of ductilities (3-36%) being obtained at the strain rates of interest. Strain controlled slow-fast creep-fatigue cycles were used with strain rates of 10 -6 s -1 , 10 -7 s -1 in tension and 10 -3 s -1 in compression. It was found that creep ductility strongly influenced the creep-fatigue endurance of the 20/25/Nb stainless steel. When failure was creep dominated endurance was found to be directly proportional to the creep ductility. A ductility exhaustion model has been used to successfully predict creep-fatigue endurance when failure was creep dominated. (author)

Evolution of secondary-phase precipitates during annealing of the 12Kh18N9T steel irradiated with neutrons to a dose of 5 DPA

Science.gov (United States)

Tsai, K. V.; Maksimkin, O. P.; Turubarova, L. G.

2007-03-01

The formation and evolution of thermally-induced secondary precipitates in an austenitic stainless steel 12Kh18N9T irradiated in the core of a laboratory reactor VVR-K to a dose of 5 dpa and subjected to post-radiation isochronous annealings for 1 h in a temperature range from 450 to 1050°C have been studied using transmission electron microscopy (TEM) and microhardness measurements. It has been shown that the formation of stitch (secondary) titanium carbides and M 23C6 carbides at grain and twin boundaries after annealing at 1050°C is preceded by a complex evolution of fineparticles of secondary phases (titanium carbides and nitrides) precipitated at dislocation loops and dislocations during annealing at temperatures above 750°C.

Effect of austenitization conditions on kinetics of isothermal transformation of austenite of structural steels

International Nuclear Information System (INIS)

Konopleva, E.V.; Bayazitov, V.M.; Abramov, O.V.; Kozlova, A.G.

1987-01-01

Effect of austenization of kinetics of pearlite and bainite transformations for steels with different carbon content differing by alloying character and degree has been investigated. Austenization temperature increase is shown to leads to retardation of ferrite-pearlite transformation in low- and medium-carbon alloyed steels. Step-like holding in the region of austenite stable state (850, 950 deg) after high-temperature heating (1100 deg C) increases the rate of transformation partially recovering its kinetics and decomposition velocity after low-temperature heating in steels alloyed advantageously with carbide-forming elements (08Kh2G2F, 30Kh3) and does not affect kinetics in the 35Kh, 30KhGSN2A, 45N5 steels. Increase of heating temperature and growth of an austenite grain cause considerable acceleration of bainite transformation, increase of the temperaure of bainite transformation beginning and increase of the transformation amplitude in the 08Kh2G2F, 30Kh3 steels and affect weakly kinetics in steels with mixed alloying (30KhGSN2A) or low-alloy one (35Kh). The bainite transformation rate in the 45N5 steelite does not depend on austenization. The effect of additional acceleration of bainite transformation as a result holding after high-temperature heating in those steels, where activation of transformation occurs with increase of heating temperature

Effect of smelt aluminium on mechanical properties of steels

International Nuclear Information System (INIS)

Ryabov, V.R.; Dykhno, I.S.; Deev, G.F.; Karikh, V.V.

1987-01-01

Effect of smelt aluminium on mechanical properties of armco-iron and 12 Kh18N10T steel is studied. It is stated that in smelt aluminium and aluminium alloy contact with armco-iron the sample ductility is decreased. Corrosion effect of smelt alluminium on (18Kh15N5AM3) steel in the form of reinforced wire in aluminium-steel KAS-1A composite material is investigted. It is stated in experiment that during smelt alluminium-steel contact interaction of heterogeneous phases takes place

Local corrosion of high alloy steels under biodeposits

International Nuclear Information System (INIS)

Korovyakova, M.D.; Nikitin, V.M.; Speshneva, N.V.

1999-01-01

Impact of the bacteriozenosis different structural-functional state under biodeposits on corrosion resistance of the 12Kh18N10T and Kh18N10T high-alloy steels in the natural seawater is studied. It is shown that saturation of natural micro communities by separate aerobic and facultative-anaerobic bacterial monocultures increases corrosion resistance of these steels by their overgrow with biodeposits [ru

Platelet activation by bacterial phospholipase C involves phosphoinositide turnover and phosphorylation of 47,000 dalton but not 20,000 dalton protein

International Nuclear Information System (INIS)

Huzoor-Akbar; Anwer, K.

1986-01-01

This study was conducted to examine the role of phosphoinositides (PIns) and phosphorylation of 47,000 dalton (P47) and 20,000 dalton (P20) proteins in platelet activation by bacterial phospholipase C (PLC). PLC induced serotonin secretion (SS) and platelet aggregation (PA) in a concentration dependent manner. PLC (0.02 U/ml) caused phosphorylation of P47 in a time dependent manner (27% at 0.5 min to 378% at 7 min). PLC did not induce more than 15% phosphorylation of P20 by 7 min. Aspirin (500 μM) blocked phosphorylation of P20 but did not inhibit SS, PA or phosphorylation of P47. PLC (0.04 U/ml) decreased radioactivity (cpm) in 32 P labeled phosphatidylinositol (PI), PI-4,5-bis-PO4 (PIP2) and PI-4-PO4 (PIP) by 20%, 12% and 7.5% respectively at 15 sec. The level of PI but not that of PIP2 returned to base line in 3 min. PIP level increased above control values within one min. PLC increased phosphatidic acid level (75% at 0.5 min. to 1545% at 3 min). In other experiments PLC produced diacylglycerol (DAG) in a time and concentration dependent manner. However, no DAG was detectable in the first 60 sec. These data suggest that: (a) PIns turnover and phosphorylation of P47 but not that of P20 is involved in platelet activation by PLC; and (b) DAG production from outer membrane phospholipids is not a prerequisite for platelet activation by PLC

Influence of isothermal thermomechanical treatment on structure and properties of structural steels

International Nuclear Information System (INIS)

Smirnov, M.A.; Kaletin, A.Yu.; Schastlivthev, V.M.; Kaletina, Yu.V.

1997-01-01

A study is made into the structure and mechanical properties of steel 35KhGSA and 37KhN3A after isothermal hardening resulting in bainitic structure formation as well as after low-temperature thermomechanical treatment (LTTMT) combining the plastic deformation at the temperature of bainitic transformation and subsequent isothermal hardening. It is shown that LTTMT permits and essential enhancement of strength properties in steel 35KhGSA, high plasticity and impact strength being reserved. This is associated with bainitic structure refinement. In steel 37KhN3A the process of carbide formation takes place along with bainitic transformation, and LTTMT results in lesser strengthening. LTTMT is fount to not practically affect the tendency of structural steels to bainitic brittleness. This treatment promotes some shift of brittleness manifestation to lower temperatures

Corrosion behavior of austenitic steels and their components in niobium-containing chloride melts

Science.gov (United States)

Abramov, A. V.; Polovov, I. B.; Rebrin, O. I.; Volkovich, V. A.; Lisienko, D. G.

2014-02-01

The mechanism of corrosion of austenitic steels 12Kh18N10T, 10Kh17N13M2T, and 03Kh17N14M3 and metals Cr, Fe, Ni, and Mo in a NaCl-KCl-NbCl n ( n = 3.5, Nb content is 5 ± 0.1 wt %) melt at 750°C is studied. The metal and steel corrosion rates under these conditions are determined. The character of material fracture and the mechanisms of material corrosion are found.

Corrosion of austenitic steels and their components in vanadium-containing chloride melts

Science.gov (United States)

Abramov, A. V.; Polovov, I. B.; Rebrin, O. I.; Lisienko, D. G.

2014-08-01

The corrosion of austenitic 12Kh18N10T, 10Kh17N13M2T, and 03Kh17N14M3 steels and their components (Cr, Fe, Ni, Mo) in NaCl-KCl-VCl2 melts with 5 wt % V at 750°C is studied. The rates and mechanisms of corrosion of the materials under these conditions are determined. The processes that occur during contact of the metals and steels with vanadium-containing chloride electrolytes are investigated.

Effect of heat treatment and rotor steels composition on hydrogen solubility

International Nuclear Information System (INIS)

Ivanov, A.I.; Samojlenko, L.V.; Gorovaya, O.N.; Najdovskij, A.G.; Bilik, I.; Kret, Ya.

1988-01-01

Measurements of equilibrium hydrogen adsorption in samples of 27KhN3MFA and 25Kh2NMFA steels were conducted. Carbide inclusions and doping additions, typical for rotor steels, don't produce noticeable effect on hydrogen solubility in

Investigation of intergranular corrosion resistance of Cr16Ni25NMo6 steel

International Nuclear Information System (INIS)

Kamenev, Yu.B.; Nazarov, A.A.; Kuusk, L.V.; Majdeburova, T.F.

1990-01-01

The effect of 08Kh16N25AM6 steel susceptibility to intergranular corrosion on its intergranular cracking resistance in high-temperature water is investigated. In addition, the performed tests point to the susceptibility of sensibilized Kh16N25AM6 steel to intergranular corrosion in media simulating an agressive environment of power generation equipment; the latter requires a strict control over the resistance of weld joints of the above steel to intergranular corrosion. It is shown that Kh16N25AM6 type steel in sensibilized state is susceptible to intercrystalline corrosion cracking in high-temperature water which correlates with its susceptibility to intergranular corrosion established by AM GOST 6032-84 and potentiodynamic reactivation methods

Investigation of 12Kh1MF steel resistance to brittle fractures

International Nuclear Information System (INIS)

Bologov, G.A.; Rushchits, T.Yu.

1977-01-01

The metal of hot-rolled steam pipe made of 12Kh1MF steel, which has been subjected to thermal treatment under laboratory conditions, and metal samples from acting steam pipes after different exploitation periods at 510-565 deg C have been investigated. The dependence of impact viscosity and its constituents on conditions of thermal treatment has been established. The energy consumed by the developing crack has been used as an impact viscosity criterion. Appropriate thermal treatment is capable of rehabilitating the impact viscosity of embrittled metal. Cold plastic deformation increases crack propagation rate in the initial metal and promotes embrittlement during exploitation. Ageing of the working metal reduces its capacity of stopping the developing crack and shifts the temperature threshold of brittleness towards positive temperature

Effect of boron control of environment on corrosion and resistance to low-cycle corrosion fatigue in structural steels

International Nuclear Information System (INIS)

Babej, Yu.I.; Zhitkov, V.V.; Zvezdin, Yu.I.; Liskevich, I.Yu.; Nazarov, A.A.

1982-01-01

Tests of the specimens on total, contact and crevice corrosion, corrosion cracking and low-cycle fatigue are conducted for determination of corrosion and corrosion-fatigue characteristics in the 15Kh3NMFA, 10N3MFA, 10Kh16N4B, 05Kh13N6M2 structural steels, used in energetics. The environment is subjected to boron control and contacting with atmosphere for simulation of stop and operation modes of the facility. The experiments are carried out in the distilled water with 12g/l H 3 BO 3 and 10 mg/l Cl' at 25, 60, 100 deg C under contacting with atmosphere. It is established, that the pearlitic steels 15Kh3NMFA, 10N3MFA, as well as transition and martensitic 05Kh13N6M2 and 10Kh16N4B steels are highly stable to total, crevice and contact corrosion at the high parameters of aqueous boron-containing medium. Steel resistance to low-cycle fracture decreases slightly under the conditions similar to the operation ones, in the water with 12 g/l H 3 BO 3 . Durability of the pearlitic steels at the simulation of stop conditions decreases more noticeably, crack formation as a rule, initiating from corrosion spots

Refinement of grain structure in 20 MnNiMo (SA508C) steel

International Nuclear Information System (INIS)

Sheng Zhongqi; Xiao Hong; Peng Feng; Zou Min

1997-04-01

The size of prior austenite grains and bainitic colonies of 20 MnNiMo (SA508C) steel (a reactor pressure vessel steel) after normal heat treatment is measured and its controlling factors are discussed. Results show that low aluminium content can induce serious mixed structure with fine and coarse grains in prior austenite. Fast cooling rate can promote refinement of bainitic colonies. Further refinement of grains can be obtained by inter-critical quenching. (5 figs., 1 tab.)

Observations on thermally cycled 20% Cr/25% Ni/Nb stabilised stainless steel

International Nuclear Information System (INIS)

Lobb, R.C.

1984-06-01

A variety of optical and electron techniques, such as optical metallography, scanning electron microscopy and electron probe microanalysis, have been used to study the morphology and composition of oxides formed on 20 Cr/25 Ni/Nb stainless steel during oxidation at 850 0 C and subsequent thermal cycling in simulated reactor gas. (author)

Cyclic crack resistance of anticorrosion cladding-15Kh2MFA steel joint

International Nuclear Information System (INIS)

Zvezdin, Yu.I.; Nikiforchin, G.N.; Timofeev, B.T.; Zima, Yu.V.; Andrusiv, B.N.

1985-01-01

Cyclie crack resistance of transition zone in austenitic cladding steel 15Kh2MFA joint is studied, taking into account the geometry of fatigue cracks, fracture micromechanism and crack closure effect. Kinetics of crack development from the cladding to the basic metal and vice versa is considered. Microstructure of transition zone is investigated. The results obtained are considered as applied to WWER. It is emphasized, that the braking of fatigue cracks is observed at low asymmetry of loading cycle. Increased loading asymmetry accelerates sharply the alloy fracture due to the growth of subcladding crack, at that, the direction of crack propagation and the structure of transition zone are not of great importance

Investigation into the Cyclic Strength of the Bodies of Steam Shutoff Valves from 10Kh9MFB-Sh Steel

Science.gov (United States)

Skorobogatykh, V. N.; Kunavin, S. A.; Prudnikov, D. A.; Shchenkova, I. A.; Bazhenov, A. M.; Zadoinyi, V. A.; Starkovskii, G. L.

2018-02-01

Steam shutoff valves are operated under complex loading conditions at thermal and nuclear power stations. In addition to exposure to high temperature and stresses resulting in fatigue, these valves are subjected to cyclic loads in heating-up-cooling down, opening-closing, etc. cycles. The number of these cycles to be specified in designing the valves should not exceed the maximum allowable value. Hence, the problem of cyclic failure rate of steam shutoff valve bodies is critical. This paper continues the previous publications about properties of the construction material for steam shutoff valve bodies (grade 10Kh9MFB-Sh steel) produced by electroslag melting and gives the results of investigation into the cyclic strength of this material. Fatigue curves for the steal used for manufacturing steam shutoff valve bodies are presented. The experimental data are compared with the calculated fatigue curves plotted using the procedures outlined in PNAE G-002-986 and RD 10-249-98. It is confirmed that these procedures may be used in designing valve bodies from 10Kh9MFB-Sh steel. The effect of the cyclic damage after preliminary cyclic loading of the specimens according to the prescribed load conditions on the high-temperature strength of the steel is examined. The influence of cyclic failure rate on the long-term strength was investigated using cylindrical specimens with a smooth working section in the as-made conditions and after two regimes of preliminary cyclic loading (training) at a working temperature of 570°C and the number of load cycles exceeding the design value, which was 2 × 103 cycles. The experiments corroborated that the material (10Kh9MFB-Sh steel) of the body manufactured by the method of electroslag melting had high resistance to cyclic failure rate. No effect of cyclic damages in the metal of the investigated specimens on the high-temperature strength has been found.

Effect of combined addition of N and Nb on the high temperature behavior of a 25Cr-20Ni stainless steel

International Nuclear Information System (INIS)

Park, In Duck; Nam, Ki Woo

2002-01-01

In order to clarify the effect of precipitates on creep strength at high temperature in 25Cr-20Ni stainless steels, threshold stress and void-hardening stress have been measured and compared each others. The value of threshold stress for high temperature, measured by stress abruptly loading test, is about 130 MPa. Threshold stress must be measured by the function of stress loading time in the combination hardening steel of solution hardening and precipitate hardening. Average diameter and inter-partial distance of precipitates from TEM microstructure can determine void-hardening stress. The value of void-hardening stress, evaluated by using Scattergood and Bacon's equation, was from 101 to 130 MPa. The ratio of average void hardening to threshold stress is 1.13 and both values are not equal. The result from analyzing the electron diffraction pattern shows that the dispersed precipitates in SUS310J1TB is NbCrN nitrides. Mechanism of the interaction between dislocations and precipitate particles in SUS310J1TB is Srolovitz mechanism, which is a gravitation-type interaction

Creep damage in welds of X 20 CrMoV 12 1 steel. Part 2 - Studies of long term service exposed material and damage data base and calculation of damage distribution and damage resistance; Krypskador i svetsar av X 20 CrMoV 12 1 staal. Etapp 2 - Studier av lingtidspiverkat material och skadedatabas samt berakning av skadefordelning och skadetilighet

Energy Technology Data Exchange (ETDEWEB)

Storesund, Jan; Borggreen, Kjeld; Weilin Zang; Nilsson, Henrik; Samuelson, Aake

2004-09-01

The present project has been consisted of the following pieces of work on welds of X20 CrMoV 12 1: Analysis of, by use of replica testing, creep damage development in 368 welds in 11 Danish high pressure steam lines with operation up to 200,000 h. Metallographic investigations of four welds from a retired live steam line with approximately 182 000 h in operation. - Evaluation of the influence of the two most common etching methods on the interpretation of creep cavitation. Analysis of the time security of the material, i.e. influence of enhanced temperature or stress on creep life time. Finite element simulations of the creep behaviour of X20 welds where effects of HAZ creep properties, system stresses and degree of multiaxiality in the rupture criterion are studied. In addition a literature study on publications of creep life time in X20 steel was performed in a first, already reported part of the project. The results of the comprehensive replica testing and the metallographic investigations show clear-cut that welds of this material have an excellently long creep life that indeed will reach 200,000 h. The creep damage at that time is in general very limited. The typical creep life for welds of X20 can be evaluated to at least 250,000 h. The reason for that it is not possible to evaluate an even longer creep life is the fact that creep testing and finite element simulations show that creep elongation and creep damage will accelerate considerably later in the creep life than some low alloy steels. In the worst case this acceleration could start already just after 200,000 h. It is also demonstrated that welds of the X20 steel can stand system stresses much better than low alloy steels. Recommendations for how and when inspections and testing of welds of the current material should be performed have been issued. They have been adapted to the findings in the project. The recommendations can, as long as severe damage is absent, allow for longer inspection intervals

Hot Deformation Behavior and a Two-Stage Constitutive Model of 20Mn5 Solid Steel Ingot during Hot Compression

Directory of Open Access Journals (Sweden)

Min Liu

2018-03-01

Full Text Available 20Mn5 steel is widely used in the manufacture of heavy hydro-generator shaft forging due to its strength, toughness, and wear resistance. However, the hot deformation and recrystallization behaviors of 20Mn5 steel compressed under a high temperature were not studied. For this article, hot compression experiments under temperatures of 850–1200 °C and strain rates of 0.01 s−1–1 s−1 were conducted using a Gleeble-1500D thermo-mechanical simulator. Flow stress-strain curves and microstructure after hot compression were obtained. Effects of temperature and strain rate on microstructure are analyzed. Based on the classical stress-dislocation relationship and the kinetics of dynamic recrystallization, a two-stage constitutive model is developed to predict the flow stress of 20Mn5 steel. Comparisons between experimental flow stress and predicted flow stress show that the predicted flow stress values are in good agreement with the experimental flow stress values, which indicates that the proposed constitutive model is reliable and can be used for numerical simulation of hot forging of 20Mn5 solid steel ingot.

Cholecalciferol 20 000 IU Once Weekly in HIV-Positive Patients with Low Vitamin D Levels: Result from a Cohort Study.

Science.gov (United States)

Noe, Sebastian; Heldwein, Silke; Pascucchi, Rita; Oldenbüttel, Celia; Wiese, C; von Krosigk, Ariane; Jägel-Guedes, Eva; Jäger, Hans; Mayer, Wolfgang; Spinner, Christoph D; Wolf, Eva

To evaluate efficacy and safety of 20 000 IU cholecalciferol weekly in HIV-infected patients. Longitudinal data for 243 HIV-infected patients with paired 25-OH-vitamin D3 values for the same month in 2 consecutive years were stratified by the initiation of supplementation in this retrospective study. After 1 year of administration of cholecalciferol 20 000 IU weekly, about 78% of patients with initial vitamin D level L achieved vitamin D levels >20 µg/L and 42% achieved levels >30 µg/L. Supplemented patients with baseline vitamin D levels L showed a significant risk reduction for hypocalcemia ( P = .006; risk difference: 20.8%) and a significantly lower increase in alkaline phosphatase (AP) compared to those in the nonsubstituted group. The dose of 20 000 IU of cholecalciferol once weekly was found to be safe and effective. Normalization of vitamin D levels within 1 year was observed in 42% to 75% of the patients.

Effectiveness and safety of a high-dose weekly vitamin D (20,000 IU) protocol in older adults living in residential care.

Science.gov (United States)

Feldman, Fabio; Moore, Crystal; da Silva, Liz; Gaspard, Gina; Gustafson, Larry; Singh, Sonia; Barr, Susan I; Kitts, David D; Li, Wangyang; Weiler, Hope A; Green, Timothy J

2014-08-01

To report 25 hydroxyvitamin D (25OHD) concentrations, an indicator of vitamin D status, in older adults living in residential care 1 year after a protocol of weekly 20,000 IU of vitamin D was started. Cross-sectional. Five residential care facilities in British Columbia, Canada. Residents aged 65 and older from five facilities (N=236). Participants provided a blood sample. Demographic and health information was obtained from the medical record. Mean 25OHD was 102 nmol/L (95% confidence interval (CI)=98-106 nmol/L). Three percent of residents had a 25OHD concentration of less than 40 nmol/L, 6% 2.6 mmol/L), a potential consequence of too much vitamin D, was present in 14%, although 25OHD levels did not differ in those with and without hypercalcemia (108 vs 101 nmol/L; P=.17). Twelve months after implementation of a 20,000-IU/wk vitamin D protocol for older adults in residential care, mean 25OHD concentrations were high, and there was no evidence of poor vitamin D status. Given the absence of demonstrated benefit of high 25OHD concentrations to the residential care population, dosages less than 20,000 IU/wk of vitamin D are recommended. © 2014, Copyright the Authors Journal compilation © 2014, The American Geriatrics Society.

Microstructure of steel X 20 Cr 13 in the electron microscopical picture

International Nuclear Information System (INIS)

Gesatzke, W.

1982-01-01

The tempered microstructure of the steel X 20 Cr 13 is described by an electron microscopical overall picture and additional information is gained which would not be possible with the optical microscope. The large transmission area permits one to quantitatively evaluate a microstructure component which due to its small size can only be measured with electron microscope pictures. (orig.) [de

The 20-20-20 Airships NASA Centennial Challenge

Science.gov (United States)

Kiessling, Alina; Diaz, Ernesto; Rhodes, Jason; Ortega, Sam; Eberly, Eric

2015-08-01

A 2013 Keck Institute for Space Studies (KISS) study examined airships as a possible platform for Earth and space science. Airships, lighter than air, powered, maneuverable vehicles, could offer significant gains in observing time, sky and ground coverage, data downlink capability, and continuity of observations over existing suborbital options at competitive prices. The KISS study recommended three courses of action to spur the development and use of airships as a science platform. One of those recommendations was that a prize competition be developed to demonstrate a stratospheric airship. Consequently, we have been developing a NASA Centennial Challenge; (www.nasa.gov/challenges) to spur innovation in stratospheric airships as a science platform. We anticipate a multi-million dollar class prize for the first organization to fly a powered airship that remains stationary at 20km (65,000 ft) altitude for over 20 hours with a 20kg payload. The design must be scalable to longer flights with more massive payloads. A second prize tier, for a 20km flight lasting 200 hours with a 200kg payload would incentivize a further step toward a scientifically compelling and viable new platform. This technology would also have broad commercial applications including communications, asset tracking, and surveillance. Via the 20-20-20 Centennial Challenge, we are seeking to spur private industry (or non-profit institutions, including Universities) to demonstrate the capability for sustained airship flights as astronomy and Earth science platforms.

Sydlangeland Fjernvarme A.m.b.a. Feasibility study on 10-20.000 m{sup 3} pond heat storage[Denmark]; Sydlangeland Fjernvarme A.m.b.a. Forundersoegelse for 10-20.000 m{sup 3} damvarmelager

Energy Technology Data Exchange (ETDEWEB)

Visbjerg, L. [Sydlangeland Fjernvarme A.m.b.a. (Denmark); Wesenberg, C.; Bliksted, T. [NIRAS Raadgivende Ingenioerer og Planlaeggere A/S (Denmark); Porsvig, M. [Geoteknisk Institut (Denmark); Duer, K. [DTU, Solenergi Center Danmark (Denmark)

2000-11-01

The project includes siting analyses, geotechnical feasibility studies and evaluations of operating economy for establishing a seasonal heat storage carried out as a 10-20,000 m{sup 3} pilot pond heat storage at Sydlangeland straw-fired district heating plant. (EHS)

The 20-20-20 Airship Challenge

Science.gov (United States)

Kiessling, Alina; Diaz, Ernesto; Miller, Sarah; Rhodes, Jason

2014-06-01

A NASA Centennial Challenge; (http://www.nasa.gov/directorates/spacetech/centennial_challenges/index.html) is in development to spur innovation in stratospheric airships as a science platform. We anticipate a million dollar class prize for the first organization to fly a powered airship that remains stationary at 20km (65,000 ft) altitude for over 20 hours with a 20kg payload. The design must be scalable to longer flights with more massive payloads.In NASA’s constrained budget environment, there are few opportunities for space missions in astronomy and Earth science, and these have very long lead times. We believe that airships (powered, maneuverable, lighter-than-air vehicles) could offer significant gains in observing time, sky and ground coverage, data downlink capability, and continuity of observations over existing suborbital options at competitive prices. We seek to spur private industry (or non-profit institutions, including FFRDCs and Universities) to demonstrate the capability for sustained airship flights as astronomy and Earth science platforms. This poster will introduce the challenge in development and provide details of who to contact for more information.

First attempts towards the early detection of fatigued substructures using cyclic-loaded 20 MnMoNi 5 5 steel

International Nuclear Information System (INIS)

Dobmann, G.; Seibold, A.

1992-01-01

Materials subjected to cyclic loading undergo substructural changes which may affect service life. The low alloy, fine-grained structural steel 20 MnMoNi 5 5 is used to demonstrate how substructural changes detected using TEM techniques are a function of the number of cycles undergone. For a given cyclic loading the usage factor η=N/N f =0.5 can be derived. Initial investigations using nondestructive examination methods have indicated that substructural changes and magnetic variables can be correlated. (orig.)

Excellent corrosion resistance of 18Cr-20Ni-5Si steel in liquid Pb-Bi

International Nuclear Information System (INIS)

Kurata, Y.; Futakawa, M.

2004-01-01

The corrosion properties of three austenitic steels with different Si contents were studied under oxygen-saturated liquid Pb-Bi condition for 3000 h. The three austenitic steels did not exhibit appreciable dissolution of Ni and Cr at 450 deg. C. At 550 deg. C, the thick ferrite layer produced by dissolution of Ni and Cr was found in JPCA and 316SS with low Si contents while the protective oxide film composed of Si and O was formed on 18Cr-20Ni-5Si steel and prevented dissolution of Ni and Cr

What Happens in the Atmospheres of Hot Horizontal Branch Stars Near 20, 000K?

Science.gov (United States)

Brown, Thomas

2016-10-01

In the color-magnitude diagrams (CMDs) of many globular clusters, the horizontal branch (HB) exhibits a long blue tail extending to high effective temperatures. In such clusters, two discontinuities appear within the HB locus. The first discontinuity occurs at 12,000K, and was discovered by Grundahl et al. (1998). It is associated with the radiative levitation of metals and the gravitational settling of helium in the atmospheres of HB stars hotter than 12,000K. The hot subdwarf stars of the Galactic field population exhibit the same phenomenon. The second discontinuity occurs at 20,000K, and was discovered by Momany et al. (2002). Its origin is unknown, but it appears at the same effective temperature in all globular clusters hosting HB stars near 20,000K, regardless of cluster properties (age, chemical composition, mass, etc.). We propose STIS long-slit spectroscopy of 6 HB stars that straddle this feature in the HB distribution of omega Cen, the nearest globular cluster where the feature is well populated. With this approach, we can efficiently obtain high-quality UV and blue spectra that span the full wavelength range of the photometric bands where this CMD feature is most prominent - a range this is only accessible by HST. The resulting spectra will unambiguously reveal the nature of this phenomenon - one that is universal in the atmospheres of hot evolved stars - and will yield new insight into the role of diffusion and radiative levitation in these stars.

ELOVL4 protein preferentially elongates 20:5n3 to very long chain PUFAs over 20:4n6 and 22:6n3[S

Science.gov (United States)

Yu, Man; Benham, Aaron; Logan, Sreemathi; Brush, R. Steven; Mandal, Md Nawajes A.; Anderson, Robert E.; Agbaga, Martin-Paul

2012-01-01

We hypothesized that reduction/loss of very long chain PUFAs (VLC-PUFAs) due to mutations in the ELOngase of very long chain fatty acid-4 (ELOVL4) protein contributes to retinal degeneration in autosomal dominant Stargardt-like macular dystrophy (STGD3) and age-related macular degeneration; hence, increasing VLC-PUFA in the retina of these patients could provide some therapeutic benefits. Thus, we tested the efficiency of elongation of C20-C22 PUFA by the ELOVL4 protein to determine which substrates are the best precursors for biosynthesis of VLC-PUFA. The ELOVL4 protein was expressed in pheochromocytoma cells, while green fluorescent protein-expressing and nontransduced cells served as controls. The cells were treated with 20:5n3, 22:6n3, and 20:4n6, either individually or in equal combinations. Both transduced and control cells internalized and elongated the supplemented FAs to C22-C26 precursors. Only ELOVL4-expressing cells synthesized C28-C38 VLC-PUFA from these precursors. In general, 20:5n3 was more efficiently elongated to VLC-PUFA in the ELOVL4-expressing cells, regardless of whether it was in combination with 22:6n3 or with 20:4n6. In each FA treatment group, C34 and C36 VLC-PUFAs were the predominant VLC-PUFAs in the ELOVL4-expressing cells. In summary, 20:5n3, followed by 20:4n6, seems to be the best precursor for boosting the synthesis of VLC-PUFA by ELOVL4 protein. PMID:22158834

Pipes out of the chromium-molybdenum 12Kh2M1 steel intended for power units

International Nuclear Information System (INIS)

Saf'yanov, A.V.; Plyatskovskij, O.A.; Khokhlov-Nekrasov, O.G.; Palatnikova, E.S.; Karpenko, N.P.

1977-01-01

Vanadiumless steel 12Kh2M1 (2.25%Cr, 1%Mo) known to be applied abroad has been used for production of 325x60 mm tubes. The technology involves heating of the blanks to 1270-1300 deg C, their piercing in a double-roller mill, rolling on a pilger mill 8-16'' in thick wall caliber rolls, thermal treatment (normalizing at 930-960 deg C for 1 hour and tempering at 730+-10 deg C for 4 hours and etching (12-22% H 2 SO 4 and up to 143 g/l FeSO 4 ) for 3-4 hours at 55-65 deg C. Good technological properties of the steel and its capacity of working at 540-580 deg C are confirmed. Vanadium alloying of boiler steels does not provide for essential improvement of oxydation resistance and long term strength, but decreases the workability and enhances scatter of working parameters on account of minor variations of chemical composition

Heat treatment effect on the properties of the EhP767 maraging steel welded joints

International Nuclear Information System (INIS)

Taver, E.I.; Piskarev, M.N.; Yushchenko, K.A.; Pustovit, A.I.; Anisimova, M.S.

1977-01-01

Heat treatment effect on properties of welded joints of maraging 03Kh13N4K13M3T (EhP767) steel with yield strength over 150 kgs/mm 2 has been investigated. It is shown, that change in impact strength of aged joints at - 196 deg C depends on the amount of residual austenite and grain size. To stabilize 20-40 % residual austenite heat treatment regimes have been developed. Recommended are quenching at 1030-1050 deg C, sub-zero treatment and aging at 520 deg C for 16 hrs

Chemical heat treatment of low alloyed maraging steels

Energy Technology Data Exchange (ETDEWEB)

Malinov, L S; Korotich, I K [Zhdanovskij Metallurgicheskij Inst. (Ukrainian SSR)

1979-09-01

The investigation concerned the nitriding, cementation, chromizing, borating of economically alloyed maraging grade 04Kh2N5MFYu steel. The investigated methods of chemothermal treatment were found to considerably increase the hardness of the surface layer of the maraging steel. The high tempering of the grade 04Kh2N5MFYu cemented and hardened steel was found to produce secondary hardening. On chromizing, the diffusion layer is an alloyed ferrite which strengthens because of the dispersion hardening on ageing. The formation of the plastic low-carbon martensite at relatively small cooling rates greatly decreases the tendency of the boride layer to cracking.

Study of mechanical properties and high temperature oxidation behavior of a novel cold-spray Ni-20Cr coating on boiler steels

Energy Technology Data Exchange (ETDEWEB)

Kaur, Narinder [Semiconductor Materials and Device Laboratory, Department of Semiconductor Science, Dongguk University-Seoul, Seoul 100715 (Korea, Republic of); Kumar, Manoj [School of Mechanical, Materials & Energy Engineering, Indian Institute of Technology Ropar, Rupnagar, Punjab (India); Sharma, Sanjeev K.; Kim, Deuk Young [Semiconductor Materials and Device Laboratory, Department of Semiconductor Science, Dongguk University-Seoul, Seoul 100715 (Korea, Republic of); Kumar, S.; Chavan, N.M.; Joshi, S.V. [International Advanced Research Centre for Powder Metallurgy & New Materials (ARCI), Hyderabad 500005 (India); Singh, Narinder [Department of Chemistry, Indian Institute of Technology Ropar, Rupnagar, Punjab (India); Singh, Harpreet, E-mail: harpreetsingh@iitrpr.ac.in [School of Mechanical, Materials & Energy Engineering, Indian Institute of Technology Ropar, Rupnagar, Punjab (India)

2015-02-15

Highlights: • A presynthesized Ni-20Cr nanocrystalline powder was successfully deposited on T22 and SA 516 boilers steels using cold spray process. • The coatings are observed to have more than 2-folds microhardness in comparison with the base steels. • The coating was successful in reducing the weight gain of T22 and SA 516 steel by 71% and 94%. - Abstract: In the current investigation, high temperature oxidation behavior of a novel cold-spray Ni-20Cr nanostructured coating was studied. The nanocrystalline Ni-20Cr powder was synthesized by the investigators using ball milling, which was deposited on T22 and SA 516 steels by cold spraying. The crystallite size based upon Scherrer's formula for the developed coatings was found to be in nano-range for both the substrates. The accelerated oxidation testing was performed in a laboratory tube furnace at a temperature 900 °C under thermal cyclic conditions. Each cycle comprised heating for one hour at 900 °C followed by cooling for 20 min in ambient air. The kinetics of oxidation was established using weight change measurements for the bare and the coated steels. The oxidation products were characterized by X-ray Diffraction (XRD), Scanning Electron Microscopy/Energy Dispersive Spectroscopy (SEM/EDS) and X-ray mapping techniques. It was found from the results that the coating was successful in reducing the weight gain of SA213-T22 and SA 516-Grade 70 steel by 71% and 94%, respectively. This may be attributed to relatively denser structure, lower porosity and lower oxide content of the coating. Moreover, the developed nano-structured Ni-20Cr powder coating was found to perform better than its counterpart micron-sized Ni-20Cr powder coating, in terms of offering higher oxidation resistance and hardness.

Chromium surface alloying of structural steels during laser treatment

International Nuclear Information System (INIS)

Kurov, I.E.; Nagornykh, S.N.; Sivukhin, G.A.; Solenov, S.V.

1987-01-01

Results of matrix alloying from the surface layer and creation of considerably increased chromium concentration in the depth which permits to increase the efficiency of laser treatment of steels (12Kh18N10T and 38KhN3M) in the process of their further mechanical polishing, are presented. The treatment was realized by continuous CO 2 -laser at different power densities and scanning rates are presented. A model describing the creation of anomalous distributions of the alloying element in steels is plotted

Low-temperature nitriding of austenitic steel in a vibrofluidized bed

Science.gov (United States)

Baraz, V. R.; Grachev, S. V.

1999-11-01

The prospects for use of a vibrofluidized bed (VFB) for low-temperature nitrogen saturation of high-strength austenitic steel based on Cr-Ni-Mn (12Kh17N8G2S2MF) are considered. The positive effect of preliminary plastic deformation on the intensity of nitriding is described. The temperature and time parameters of nitriding in a VFB for strain-aging austenitic steel 12Kh17N8G2S2MF are shown to be adequate for the regimes of the final heat-treatment operation of aging. This creates the possibility of combining the operations of surface alloying and strain aging into a single cycle. This combined treatment increases substantially the resistance of the steel to cyclic loads while preserving the strength parameters. It is shown that the presented method of low-temperature nitriding in a VFB is expedient for improving the service characteristics of austenitic steel 12Kh17N8G2S2MF used for production of force springs of automobile brake systems.

SCC growth behavior of stainless steel weld metals in high-temperature water. Influence of corrosion potential, weld type, thermal aging, cold-work and temperature

International Nuclear Information System (INIS)

Yamada, Takuyo; Terachi, Takumi; Miyamoto, Tomoki; Arioka, Koji

2009-01-01

Recent studies on crack growth rate measurement in oxygenated high-temperature pure water conditions, such as normal water chemistry in boiling water reactors, using compact tension type specimens have shown that weld stainless steels are susceptible to stress corrosion cracking. However, to our knowledge, there is no crack growth data of weld stainless steels in pressurized water reactor primary water. The principal purpose of this study was to examine the SCC growth behavior of stainless steel weld metals in simulated PWR primary water. A second objective was to examine the effect of (1) corrosion potential, (2) thermal-aging, (3) Mo in alloy and (4) cold-working on SCC growth in hydrogenated and oxygenated water environments at 320degC. In addition, the temperature dependence of SCC growth in simulated PWR primary water was also studied. The results were as follows: (1) No significant SCC growth was observed on all types of stainless steel weld metals: as-welded, aged (400degC x 10 kh) 308L and 316L, in 2.7 ppm-hydrogenated (low-potential) water at 320degC. (2) 20% cold-working markedly accelerated the SCC growth of weld metals in high-potential water at 320degC, but no significant SCC growth was observed in the hydrogenated water, even after 20% cold-working. (3) No significant SCC growth was observed on stainless steel weld metals in low-potential water at 250degC and 340degC. Thus, stainless steel weld metals have excellent SCC resistance in PWR primary water. On the other hand, (4) significant SCC growth was observed on all types of stainless steel weld metals: as-weld, aged (400degC x 10 kh) and 20% cold-worked 308L and 316L, in 8 ppm-oxygenated (high-potential) water at 320degC. (5) No large difference in SCC growth was observed between 316L (Mo) and 308L. (6) No large effect on SCC growth was observed between before and after aging up to 400degC for 10 kh. (7) 20% cold-working markedly accelerated the SCC growth of stainless steel weld metals. (author)

Parametrical limits of SCC-susceptibility of austenitic and austenitic-ferritic Cr-Ni steels

International Nuclear Information System (INIS)

Starosvetskij, D.I.; Baru, R.L.; Bondarenko, A.I.; Bogoyavlenskij, V.L.; Timonin, V.A.

1990-01-01

Comparative investigations into corrosion cracking (CC) of austenitic (12Kh18N10T) and austenitic-ferritic (08Kh22N6T) chromium-nickel steels are performed for various chloride media in a wide range of chloride concentrations and temperatures. It is shown that the ratio between steels in terms of their CC-susceptibility is not definite and can undergo a reversal depending on parameters of medium, level and conditions of loading. Differences in mechanisms of corrosion cracking of austenitic and austenitic-ferritic steels are established

Fracture behaviour of steel 20 MnMoNi 5 5 under stress wave loading

International Nuclear Information System (INIS)

Clos, R.; Schreppel, U.; Veit, P.; Zencker, U.; Specht, E.

1994-01-01

Crack initiation in fine grained 20 MnMoNi 5 5 steel has been investigated under stress wave loading conditions in the temperature range from -50 C to 20 C by a loading setup similar the ''Split Hopkinson Pressure Bar'' technique. For temperatures up to 20 C, fracture occurs by cleavage and K Id approaches and falls below the reference fracture toughness, while at room temperature stable crack growth occurs with a J i close to the static initiation value of the J-integral. The analysis of the crack tip configuration suggests that stable crack growth is the result of the following simultaneously induced stochastical processes: generation of constrained local microcracks, blunting of the individual crack tips and the deformation of material bridges at different regions along the crack tip front. (orig.)

Effect of Tin, Copper and Boron on the Hot Ductility of 20CrMnTi Steel between 650 °C and 1100 °C

Science.gov (United States)

Peng, Hong-bing; Chen, Wei-qing; Chen, Lie; Guo, Dong

2015-02-01

The hot ductility of 20CrMnTi steel with x% tin, y% copper and z ppm boron (x = 0, 0.02; y = 0, 0.2; z = 0, 60) was investigated. The results show that tin and copper in 20CrMnTi steel are detrimental to its hot ductility while adding boron can eliminate the adverse effect and enhance hot ductility greatly. Tin is found to segregate to the boundaries tested by EPMA in 20CrMnTi steel containing tin and copper and tin-segregation is suppressed by adding boron, moreover, copper was found not to segregate to boundaries, however, fine copper sulfide was found from carbon extraction replicas using TEM. The adverse effect of tin and copper on the hot ductility was due mainly to tin segregation and fine copper sulfide in the steel. The proeutectoid ferrite film precipitating along the austenite grain boundary causes the ductility trough of the three examined steels. Tin and copper in 20CrMnTi steel can retard the occurrence of dynamic recrystallization (DRX) while boron-addition can compensate for that change. The beneficial effect of boron on 20CrMnTi steel containing tin and copper might be ascribed to the fact that boron segregates to grain boundaries, accelerates onset of DRX, retards austenite/ferrite transformation and promotes intragranular nucleation of ferrite.

Corrosion behaviour of stainless steels by internal friction method

International Nuclear Information System (INIS)

Postnikov, V.S.; Kovalevskij, V.I.

1987-01-01

Corrosion of austenite chromium-nickel stainless steels 12 Kh18N9, 12Kh18N9T, 12Kh18N10 and 12Kh18N10T is investigated. Wire samples 0.7...0.8 mm in diameter before tests were subjected to quenching in water from the temperature of 1050...1100 deg C and part of them - to tempering at 650 deg C for 2 h. Pitting corrosion was brought about by different concentration of iron chloride solutions (C FeCl 3 ). Total corrosion has a slight effect on the character of IF (internal friction) variation that increases without the whole test period up to the moment when mechanical strength of the sample

Long-term behaviour of heat-resistant steels and high-temperature materials

International Nuclear Information System (INIS)

1987-01-01

This book contains 10 lectures with the following subjects: On the effect of thermal pretreatment on the structure and creep behaviour of the alloy 800 H (V. Guttmann, J. Timm); Material properties of heat resistant ferritic and austenitic steels after cold forming (W. Bendick, H. Weber); Investigations for judging the working behaviour of components made of alloy 800 and alloy 617 under creep stress (H.J. Penkalla, F. Schubert); Creep behaviour of gas turbine materials in hot gas (K.H. Kloos et al.); Effect of small cold forming on the creep beahviour of gas turbine blades made of Nimonic 90 (K.H. Keienburg et al.); Investigations on creep fatigue alternating load strength of nickel alloys (G. Raule); Change of structure, creep fatigue behaviour and life of X20 Cr Mo V 12 1 (by G. Eggeler et al.); Investigations on thermal fatigue behaviour (K.H. Mayer et al.); Creep behaviour of similar welds of the steels 13 Cr Mo 4 4, 14 MoV 6 3, 10 Cr Mo 910 and GS-17 Cr Mo V 5 11 (K. Niel et al.); Determining the creep crack behaviour of heat resistant steels with samples of different geometry (K. Maile, R. Tscheuschner). (orig.,/MM) [de

Optimal control of conditions of deformation during rolling the bar alloy from alloy steel

International Nuclear Information System (INIS)

Inatovich, Yu.V.; Shilov, V.A.; Shvarts, D.L.; Kudelin, S.P.

2001-01-01

A complex of programs for determining the optimal gaps between rollers during rolling of simple merchant sections of alloy steels of a wide brand assortment (12KhN3A, Kh17N2, Kh18N10T) was elaborated. Experience in calculations made according to the programs suggests advisability of their use in the automated design systems for roller calibration and for adjustment of section mills [ru

Study of regularities in propagation of thermal fatigue cracks

International Nuclear Information System (INIS)

Tachkova, N.G.; Sobolev, N.D.; Egorov, V.I.; Rostovtsev, Yu.V.; Ivanov, Yu.S.; Sirotin, V.L.

1978-01-01

Regularities in the propagation of thermal fatigue cracks in the Cr-Ni steels of the austenite class depending upon deformation conditions in the crack zone, have been considered. Thin-walled tube samples of the Kh16N40, Kh18N20 and Kh16N15 steels have been tested in the 10O reversible 400 deg C and 100 reversible 500 deg C regimes. The samples have possessed a slot-shaped stress concentrator. Stress intensity pseudocoefficient has been calculated for the correlation of experimental data. The formula for determining crack propagation rate has been obtained. The experiments permit to conclude that propagation rate of thermal fatigue cracks in the above steels depends upon the scope of plastic deformation during a cycle and stress intensity pseudocoefficient, and is determined by plastic deformation resistance during thermal cyclic loading

Comparative estimation of weld-ability of medium-alloy steels

International Nuclear Information System (INIS)

Makarov, Eh.L.; Laz'ko, V.E.

1977-01-01

Weldability of various industrial steels has been investigated as affected by mutual presence of carbon and alloying elements in a wide range of concentrations. Mechanical properties and technological strength of medium alloyed steel welded joints have been compared. Technological strength parameters have been found to sharply decrease with increasing carbon content, the decrease depending on the alloying system. Resistance to hot and cold cracking is somewhat decreased by nickel and increased by molibdenum and tungsten. The best mechanical properties are displayed by steels of the Kh2GSNVM type. Industrial evidence on argon arc welding of different constructions made of steels 1.5-20 mm thick is compared to laboratory results. Accordingly, the high strength steels are divided into three groups, i.e. those manifesting good, satisfactory and poor weldability

Long-term Stability of 9- to 12 % Cr Steels

DEFF Research Database (Denmark)

Hald, John

2004-01-01

In the recent 25 years creep rupture strength of 9- to 12 %Cr steels for steam pipes and turbines has been doubled by development of new alloys. This development has formed a basis for improved efficiency of fossil fired steam power plants by introduction of advanced steam temperatures...... and pressures. Newly developed steam pipe steels are based on modifications of well-established steels like the X 20CrMoV12 1. Balanced addition of V, Nb and N to a 9Cr 1 Mo steel led to the Modified 9 Cr steel P 91. Addition of 1% W to a 9Cr 1 MoVNbN base composition led to steel E 911 and partial replacement...... of Mo with 1.8 % W combined with a slight amount of Boron led to steel P 92. The creep rupture strength of these new alloys are now secured with long-term tests up to 100,000 hours, which demonstrate improvements of 50% (P 91), 75 % (E 911) and 100 % (P 92) in strength compared to X 20CrMoV12 1....

Effect of heat treatment regime on structural lamination in ferritic-austenitic steels

International Nuclear Information System (INIS)

Sizov, R.A.; Zakharova, M.I.; Novikov, I.I.; Bannykh, O.A.

1983-01-01

The effect of preliminary thermal treatment on lamination and viscosity of EhP-53 and KO-3 steels after durable aging at the temperature of 350 is studied. It is shown that preliminary heat treatment considerably affects lamination processes in the result of aging of 0Kh18G8N2T steel. The lowest rate of lamination and higher impact strength after aging at 350 deg C for 4500 hours corresponds to the following heat treatment: 10 hour aging at 650 deg C with cooling in the air, then quenching in water from 950 deg C after aging for 30 min and the following tempering (650 deg C, 5 hours). Unlike the 0Kh18G8N2T steel, lamination parameters of steel 0Kh22N6T practically do not change after the application of heat treatment. Nevertherless, taking into account results of impact strength, it is advisable to have thermal treatment according to the regime: quenching in water at 950 deg C after aging for 30 min

Very deep hole systems engineering studies. [20,000 ft or less

Energy Technology Data Exchange (ETDEWEB)

None

1983-12-01

Very Deep Hole (VDH) Waste Isolation is an alternative to or an augmentation of the mined geologic repository (MGR) for high-level radioactive waste. This planning study of the VDH concept identifies the significant problem areas associated with a VDH system, identifies and discusses attributes of the VDH concept, narrows discussions to a reference VDH system, and provides preliminary estimates of costs and schedule, and an engineering program plan for VDH system and equipment development. For the reference VDH selected for this study, the nuclear waste is emplaced and disposed in 20-in. holes that are drilled by modified rotary rigs and at depths of 20,000 feet or less. The waste is to be contained within a repository zone of the host rock having low porosity, low hydraulic gradient, and low permeability, and the repository zone is not penetrated by any aquifer. Thus, the depth of emplacement and characteristics of the host rock provide isolation that would preclude unacceptable migration of radionuclides to the biosphere. The VDH concept is credible and the reference system is technically feasible, logical, practical, and achievable by the year 2000, with slight modification of present technology. In terms of costs, the reference VDH system compares favorably with costs for MGR system disposal in salt, granite, shale, and basalt. 130 references, 39 figures, 17 tables.

SEGUE: A Spectroscopic Survey of 240,000 stars with g=14-20

Energy Technology Data Exchange (ETDEWEB)

Yanny, Brian; /Fermilab; Rockosi, Constance; /UC, Santa Cruz; Newberg, Heidi Jo; /Rensselaer Poly.; Knapp, Gillian R.; /Princeton U.; Adelman-McCarthy, Jennifer K.; /Fermilab; Alcorn, Bonnie; /Fermilab; Allam, Sahar S.; /Fermilab; Prieto, Carlos Allende; /Texas U. /University Coll. London; An, Deokkeun; /Ohio State U.; Anderson, Kurt S.J.; /Apache Point Observ. /New Mexico State U.; Anderson, Scott; /Washington U., Seattle

2009-02-01

The Sloan Extension for Galactic Understanding and Exploration (SEGUE) Survey obtained {approx}240,000 moderate-resolution (R {approx} 1800) spectra from 3900 {angstrom} to 9000 {angstrom} of fainter Milky Way stars (14.0 < g < 20.3) of a wide variety of spectral types, both main-sequence and evolved objects, with the goal of studying the kinematics and populations of our Galaxy and its halo. The spectra are clustered in 212 regions spaced over three quarters of the sky. Radial velocity accuracies for stars are {sigma}(RV) {approx} 4 km s{sup -1} at g < 18, degrading to {sigma}(RV) {approx} 15 km s{sup -1} at g {approx} 20. For stars with signal-to-noise ratio >10 per resolution element, stellar atmospheric parameters are estimated, including metallicity, surface gravity, and effective temperature. SEGUE obtained 3500 deg{sup 2} of additional ugriz imaging (primarily at low Galactic latitudes) providing precise multicolor photometry ({sigma}(g, r, i) {approx} 2%), ({sigma}(u, z) {approx} 3%) and astrometry ({approx}0.1) for spectroscopic target selection. The stellar spectra, imaging data, and derived parameter catalogs for this survey are publicly available as part of Sloan Digital Sky Survey Data Release 7.

Tendency of the 18-8 type corrosion-resistant steel to cracking in automatic building-up of copper and copper base alloys in argon

International Nuclear Information System (INIS)

Abramovich, V.R.; Andronik, V.A.

1978-01-01

Studied was the tendency of the 18-8 type corrosion-resistant steel to cracking during automatic building-up of copper and bronze in argon. The investigation was carried out on the 0kh18n10t steel in argon. It had been established, that the degree of copper penetration into the steel inceases with the increase in the time of the 0Kh18n10t steel contact with liquid copper. Liquid copper and copper base alloys have a detrimental effect on mechanical properties of the steel under external tensile load during intercontant. It is shown that in building-up of copper base alloys on the steel-0Kh18n10t, tendency of the steel to cracking decreases with increase in stiffness of a surfaced weld metal plate and with decrease in building-up energy per unit length. The causes of macrocracking in steel at building-up non-ferrous metals are explained. The technological procedures to avoid cracking are suggested

PLASTIC DEFORMATION ON THE MACHINED SURFACE OF STEEL Cr20Ni10MoTi AT DRILLING

Directory of Open Access Journals (Sweden)

Jozef Jurko

2009-07-01

Full Text Available Information about material machinability is very important for the machining technology. Precise and reliable information on the machinability of a material before it enters the machining process is a necessity, and this brings the verification of technological methods in practice. This article presents the conclusions of machinability tests on austenitic stainless steel according to EN-EU (ISO: steel Cr20Ni10MoTi. This article presents the conclusions of VEGA grant agency at the Ministry of Education SR for supporting research work and co-financing the projects: Grant work #01/3173/2006 with the title „Experimental investigation of cutting zones in drilled and milled stainless steels

ESTRATEGIAS DE COLABORACIÓN 2.0 PARA LA TRANSFERENCIA DE CONOCIMIENTO

Directory of Open Access Journals (Sweden)

Lillyana María Giraldo Marín

2013-12-01

Full Text Available En este artículo de investigación se analiza la colaboración 2.0, donde los empleados pueden participar e interactuar de manera individual y colectiva. La Enterprise 2.0 pone en práctica nuevos modelos de colaboración en la organización los cuales permiten a los empleados establecer escenarios donde pueden mejorar o crear nuevos productos y servicios desde estrategias colaborativas que los conduzcan al logro de un objetivo colectivo. Por lo tanto, se realiza una revisión del concepto de colaboración 2.0 en la organización y como resultado se definen algunas estrategias de colaboración 2.0 en las organizaciones que usan intensamente las tecnologías y los servicios de la Web 2.0 como apoyo a sus estrategias de negocio.

Radiation embrittlement of WWER 440 pressure vessel steel and of some improved steels by western producers

International Nuclear Information System (INIS)

Koutsky, J.; Vacek, M.; Stoces, B.; Pav, T.; Otruba, J.; Novosad, P.; Brumovsky, M.

1982-01-01

The resistance was studied of Cr-Mo-V type steel 15Kh2MFA to radiation embrittlement at an irradiation temperature of around 288 degC. Studied was the steel used for the manufacture of the pressure vessel of the Paks nuclear reactor in Hungary. The obtained results of radiation embrittlement and hardening of steel 15Kh2MFA were compared with similar values of Mn-Ni-Mo type steels A 533-B and A 508 manufactured by leading western manufacturers within the international research programme coordinated by the IAEA. It was found that the resistance of steel 15Kh2MFA to radiation embrittlement is comparable with steels A 533-B and A 508 by western manufacturers. (author)

Rates of change in natural and anthropogenic radiative forcing over the past 20,000 years.

Science.gov (United States)

Joos, Fortunat; Spahni, Renato

2008-02-05

The rate of change of climate codetermines the global warming impacts on natural and socioeconomic systems and their capabilities to adapt. Establishing past rates of climate change from temperature proxy data remains difficult given their limited spatiotemporal resolution. In contrast, past greenhouse gas radiative forcing, causing climate to change, is well known from ice cores. We compare rates of change of anthropogenic forcing with rates of natural greenhouse gas forcing since the Last Glacial Maximum and of solar and volcanic forcing of the last millennium. The smoothing of atmospheric variations by the enclosure process of air into ice is computed with a firn diffusion and enclosure model. The 20th century increase in CO(2) and its radiative forcing occurred more than an order of magnitude faster than any sustained change during the past 22,000 years. The average rate of increase in the radiative forcing not just from CO(2) but from the combination of CO(2), CH(4), and N(2)O is larger during the Industrial Era than during any comparable period of at least the past 16,000 years. In addition, the decadal-to-century scale rate of change in anthropogenic forcing is unusually high in the context of the natural forcing variations (solar and volcanoes) of the past millennium. Our analysis implies that global climate change, which is anthropogenic in origin, is progressing at a speed that is unprecedented at least during the last 22,000 years.

Terrestrial microorganisms at an altitude of 20,000 m in Earth's atmosphere

Science.gov (United States)

Griffin, Dale W.

2004-01-01

A joint effort between the U.S. Geological Survey's (USGS) Global Desert Dust and NASA's Stratospheric and Cosmic Dust Programs identified culturable microbes from an air sample collected at an altitude of 20,000 m. A total of 4 fungal (Penicillium sp.) and 71 bacteria colonyforming units (70 colonies of Bacillus luciferensis believed to have originated from a single cell collected at altitude and one colony of Bacillus sphaericus) were enumerated, isolated and identified using a morphological key and 16S rDNA sequencing respectively. All of the isolates identified were sporeforming pigmented fungi or bacteria of terrestrial origin and demonstrate that the presence of viable microorganisms in Earth's upper atmosphere may not be uncommon.

Electroplastic drawing of stainless steels

International Nuclear Information System (INIS)

Troitskij, O.A.; Spitsyn, V.I.; Sokolov, N.V.; Ryzhkov, V.G.

1977-01-01

Effect of electroplastic drawing on mechanical, magnetic and electrical properties of wire of 12Kh18N10T and Kh13N13M2 steels was studied. Pulse, direct and alternating currents were used. Direct and alternating current densities were 400 A/mm 2 , mean density of pulse current was 200 A/mm 2 . The investigations have shown that the current density increase results in decreasing the wire strengthening intensity though in increasing plastic properties. As a result of electroplastic drawing the growth of magnetic characteristics of wire occurs

Corrosion of chromium, nickel, titanium and steels in solutions of sodium and ammonium thiosulfates

International Nuclear Information System (INIS)

Grebenshchikova, S.V.; Kochergin, V.P.; Doronina, I.V.

1983-01-01

Results of gravimetric determinatiion of average rate of chromium, nickel, titatnium and steels 12Kh18N10T and VSt.3 corrosion rate in solutions 50 mass.% (NH 4 ) 2 S 2 O 3 and Na 2 S 2 O 3 in the air and nitrogen atmosphere at 333 K have been generalized. Anodic polarization curves are recorded and stationary potentials of metals and steels under the conditions are measured. It is shown that in (NH 4 ) 2 S 2 O 3 solution the rate of metal and steels corrosion is higher than in Na 2 S 2 O 3 solution indepenent of the nature of gaseous medium contacting with solution. In the series Ni → VSt.3 → 12Kh18N10T → VT1 → chromium in (NH 4 ) 2 S 2 O 3 and Na 2 S 2 O 3 solutions at 333 K corrosion resistance increases. Chromium, titanium and chromium-nickel steel 12Kh18N10T possess a high corrosion resistance

Stationary potentials and corrosion of metals and steels in sodium and potassium chloride eutectic melts saturated with hydrogen chloride

International Nuclear Information System (INIS)

Belov, V.N.; Ershova, T.K.; Kochergin, V.P.

1978-01-01

Stationary potentials have been measured at 850 deg C and corrosion rates found gravimetrically for a number of metals and steels in the eutectic NaCl-KCl melt saturated with HCl. Periodic shifts of the stationary potentials towards positive values have been established in the Ti-V-Cr-Fe-Ni, Cu-Zr-Nb-Mo, Ag-Ta-W-Pt systems, with the corrosion rate of metals decreasing in them. The stationary potentials are shown to shift towards positive values in the series: st.08 KP, st.3, Kh17N2, Kh22N6T, Kh13NChG9, 1Kh18N10T, Kh17N13M2T, OKh17N16M3T, Kh23N18, Kh25N16G7, Kh23N28M3D3T, with corrosive resistance in this series increasing

In-reactor creep rupture of 20% cold-worked AISI 316 stainless steel

International Nuclear Information System (INIS)

Lovell, A.J.; Chin, B.A.; Gilbert, E.R.

1981-01-01

Results of an experiment designed to measure in-reactor stress-to-rupture properties of 20% cold-worked AISI 316 stainless steel are reported. The in-reactor rupture data are compared with postirradiation and unirradiated test results. In-reactor rupture lives were found to exceed rupture predictions of postirradiation tests. This longer in-reactor rupture life is attributed to dynamic point defect generation which is absent during postirradiation testing. The in-reactor stress-to-rupture properties are shown to be equal to or greater than the unirradiated material stress-to-rupture properties for times up to 7000 h. (author)

Effect of helium ion bombardment on hydrogen behaviour in stainless steel

International Nuclear Information System (INIS)

Guseva, M.I.; Stolyarova, V.G.; Gorbatov, E.A.

1987-01-01

The effect of helium ion bombardment on hydrogen behaviour in 12Kh18N10T stainless steel is investigated. Helium and hydrogen ion bombardment was conducted in the ILU-3 ion accelerator; the fluence and energy made up 10 16 -5x10 17 cm -2 , 30 keV and 10 16 -5x10 18 cm -2 , 10 keV respectively. The method of recoil nuclei was used for determination of helium and hydrogen content. Successive implantation of helium and hydrogen ions into 12Kh18N10T stainless steel results in hydrogen capture by defects formed by helium ions

Astrophysical s-factor measurements for {sup 1}20Te(p,{gamma}){sup 1}21I and {sup 1}20Te(p,n){sup 1}20I reactions; {sup 1}20Te(p,{gamma}){sup 1}21I ve {sup 1}20Te(p,n){sup 1}20I reaksiyonlarinin astrofiziksel s-factor oelcuemleri

Energy Technology Data Exchange (ETDEWEB)

Gueray, R T; Oezkan, N; Yalcin, C [Kocaeli University, Kocaeli (Turkey); Goerres, J; DeBoer, R; Palumbo, A; Tan, W P; Wiescher, M [University of Notre Dame, (United States); Fueloep, Zs; Somorjai, E [Institute of Nuclear Research ATOMKI (Hungary); Lee, H Y [Argonne National Laboratory (United States)

2009-07-01

Astrophysical S-factors for the {sup 1}20Te(p,{gamma}){sup 1}21I and {sup 1}20Te(p,n){sup 1}20I reactions have been measured in the effective center-of-mass energies between 2.47 MeV and 7.93 MeV. Experimental data have been compared with the Hauser-Fesbach statistical model calculations obtained with the model codes NON-SMOKER and TALYS. The discrepancies between the experimental results and calculations can mainly be attributed to the optical model potentials used in the codes.

Structural steels for power generating equipment and heat and chemical heat treatments

International Nuclear Information System (INIS)

Astaf'ev, A.A.

1979-01-01

Development of structural steels for power generating equipment and for reactor engineering, in particular, is elucidated. Noted is utilization of the 15Kh2NMFA steels for the WWER-1000 reactor vessels, the 10GN2MFA steels for steam generators, pressurizers, vessels of the automatic emergency shut down and safety system; the 00Kh12N3DL steel for cast pump vessels and main locking bars. The recommendations on heat treatment of big forgings, for instance, ensuring the necessary complex of mechanical properties are given. Diffusion chromizing with subsequent nitriding of austenitic steels which increase durability of the components in BN reactors more than 4 times, is practised on a large scale

Aplicación de los instrumentos de reincidencia en violencia HCR-20 y SVR-20 en dos grupos de delincuentes colombianos

Directory of Open Access Journals (Sweden)

Ángela Tapias Saldaña

2011-06-01

Full Text Available Esta investigación, de tipo exploratorio, cuenta con un diseño no experimental y transversal o transeccional; tuvo por objeto determinar si los instrumentos de evaluación psicológica forense HCR-20 y SVR-20 discriminan entre un grupo de reincidentes en delitos de acceso carnal violento y un grupo de sujetos judicializados por delitos menores. Hubo presencia de los indicadores, tanto del HCR-20 como del SVR-20, en los grupos. Se encontraron diferencias significativas en los puntajes de los grupos para el SVR- 20, pero no para el HCR-20. Finalmente, se observaron nuevos factores de riesgo, que podrían incluirse en instrumentos forenses.

KH in Paraffin - KH(P): A Useful Base for Organic Synthesis

Science.gov (United States)

Taber, Douglass F.; Nelson, Christopher G.

2011-01-01

The preparation of KH as a one:one homogenate with paraffin, termed KH(P), is reported. KH(P), a solid at room temperature, is stable without special handling. On suspension in THF with a phosphonium salt, KH(P) rapidly generates the ylide. Wittig condensation with aromatic, aliphatic and α, β-unsaturated aldehydes proceeds with high Z-selectivity. KH(P) should be a generally useful base for organic synthesis. PMID:17081034

Nuevas perspectivas para la investigación en Internet: la Web 2.0 y la Empresa 2.0.

Directory of Open Access Journals (Sweden)

Romero Frías, Esteban

2010-12-01

Full Text Available Desde su creación en 1989, la World Wide Web (la Web ha revolucionado Internet, facilitando el acceso a información a muchos usuarios potenciales. Dos décadas más tarde, la Web forma parte de la vida diaria de muchas personas en todo el mundo, originando profundas transformaciones sociales que los investigadores en ciencias sociales batallan por comprender. Además, a lo largo de los últimos cinco años la Web ha sufrido importantes cambios debido al surgimiento y popularización de la llamada Web 2.0. Esto ha provocado una democratización en las herramientas de generación de información permitiendo que millones de personas se involucren en una conversación a escala global. Las tecnologías de la Web 2.0 y sus dinámicas de funcionamiento constituyen un área de gran futuro en la que profundizar en la investigación en ciencias sociales y, particularmente, en la investigación en el campo económico y de empresa. El concepto de Empresa 2.0 se deriva directamente de este nuevo contexto tecnológico.

Comparison of tool life and surface roughness with MQL, flood cooling, and dry cutting conditions with P20 and D2 steel

Science.gov (United States)

Senevirathne, S. W. M. A. I.; Punchihewa, H. K. G.

2017-09-01

Minimum quantity lubrication (MQL) is a cutting fluid (CF) application method that has given promising results in improving machining performances. It has shown that, the performance of cutting systems, depends on the work and tool materials used. AISI P20, and D2 are popular in tool making industry. However, the applicability of MQL in machining these two steels has not been studied previously. This experimental study is focused on evaluating performances of MQL compared to dry cutting, and conventional flood cooling method. Trials were carried out with P20, and D2 steels, using coated carbides as tool material, emulsion cutting oil as the CF. Tool nose wear, and arithmetic average surface roughness (Ra) were taken as response variables. Results were statistically analysed for differences in response variables. Although many past literature has suggested that MQL causes improvements in tool wear, and surface finish, this study has found contradicting results. MQL has caused nearly 200% increase in tool nose wear, and nearly 11-13% increase in surface roughness compared flood cooling method with both P20 and D2. Therefore, this study concludes that MQL affects adversely in machining P20, and D2 steels.

The precipitation response of 20%-cold-worked type 316 stainless steel to simulated fusion irradiation

International Nuclear Information System (INIS)

Maziasz, P.J.

1979-01-01

The precipitation response of 20%-cold-worked type 316 stainless steel has been examined after irradiation in HFIR at 380-600 0 C, after irradiation in EBR-II at 500 0 C, and after thermal aging at 600 to 750 0 C. Eta phase forms during exposure to all environments. It constitutes a major portion of the precipitation response, and is rich in Ni, Si and Mo relative to M 23 C 6 after thermal aging. It is not normally reported in 20%-cold-worked type 316 stainless steel. The eta, M 23 C 6 , Laves, sigma, and chi precipitate phases appear at similar temperatures after HFIR, EBR-II, or thermal exposure. There are, however, some differences in relative amounts, size, and distribution of phases among the various environments. Eta phase is the only carbide-type phase observed after irradiation in HFIR from 380-550 0 C. The large cavities associated with it at 380 0 C contribute significantly to swelling. Re-solution of fine M 23 C 6 , eta, and Laves particles and re-precipitation of massive particles of sigma, M 23 C 6 and chi are observed after recrystallization in HFIR. (orig.)

Electron beam welding of flanges with tubular shafts of steel 40KhNMA

International Nuclear Information System (INIS)

Leskov, G.I.; Zhivaga, L.I.; Shipitsyn, B.N.; Savichev, R.V.

1975-01-01

The results are presented of elaborating the technological process for the electron beam welding of flanges with a tube of the 40KhNMA steel and of investigation into the quality of the welded joints. A welded piece has been fabricated conforming to the technology suggested observing the parameters worked-out in the following sequence: assembling the piece; pre-welding of the edges in some points; welding; high tempering; welds quality control; removal of the seam reinforcement inside of the tube and the weld root to the depth of 2 mm; quenching; tempering; welds quality control; finishing. The welds quality control consists in visual inspection, ultrasonic testing, magnetic flaw detection, as well as X-ray and metallographic analyses. The mechanical properties are studied on notched samples cut out of the welded joints. The test results have shown that the mechanical properties of the welded joints meet the requirements on the same level with the base metal

Spinal N13 versus cortical N20 and dermatomal somatosensory ...

African Journals Online (AJOL)

Mohamed Imam

2013-04-06

Apr 6, 2013 ... Spinal N13 versus cortical N20 and dermatomal somatosensory .... recording point for the right upper limb stimulation and the. C40 for the left upper limb stimulation. The reference ..... Brain 1992;115:1209–34. 298. M. Imam ...

Structural features and properties of the laser-deposited nickel alloy layer on a KhV4F tool steel after heat treatment

Science.gov (United States)

Shcherbakov, V. S.; Dikova, Ts. D.; Stavrev, D. S.

2017-07-01

The study and application of the materials that are stable in the temperature range up to 1000°C are necessary to repair forming dies operating in this range. Nickel-based alloys can be used for this purpose. The structural state of a nickel alloy layer deposited onto a KhV4F tool steel and then heat treated is investigated. KhV4F tool steel (RF GOST) samples are subjected to laser deposition using a pulsed Nd:YAG laser. A nickel-based material (0.02C-73.8Ni-2.5Nb-19.5Cr-1.9Fe-2.8Mn) is employed for laser deposition. After laser deposition, the samples are subjected to heat treatment at 400°C for 5 h, 600°C for 1 h, 800°C for 1 h, and 1000°C for 1 h. The microstructure, the phase composition, and the microhardness of the deposited layer are studied. The structure of the initial deposited layer has relatively large grains (20-40 μm in size). The morphology is characterized by a cellular-dendritic structure in the transition zone. The following two structural constituents with a characteristic dendritic structure are revealed: a supersaturated nickel-based γ solid solution and a chromium-based bcc α solid solution. In the initial state and after heat treatment, the hardness of the deposited material (210-240 HV 0.1) is lower than the hardness of the base material (400-440 HV 0.1). Only after heat treatment at 600°C for 1 h, the hardness increases to 240-250 HV0.1. Structure heredity in the form of a dendritic morphology is observed at temperatures of 400, 600, and 800°C. The following sharp change in the structural state is detected upon heat treatment at 1000°C for 1 h: the dendritic morphology changes into a typical α + γ crystalline structure. The hardness of the base material decreases significantly to 160-180 HV 0.1. The low hardness of the deposited layer implies the use of the layer material in limited volume to repair the forming surfaces of dies and molds for die casting. However, the high ductility of the deposited layer of the nickel

Barium atoms and N20 molecular agregates reaction

International Nuclear Information System (INIS)

Visticot, J.P.; Mestdagh, J.M.; Alcaraz, C.; Cuvellier, J.; Berlande, J.

1988-06-01

The collisions between a barium atom and N20 molecular agregates are studied, for a better understanding of the solvation part in a chemical reaction. The experiments are carried out in a crossed molecular beam device. The light coming from the collision zone is scattered, and analysed by means of a photon detector. A time-of-flight technique is applied in the investigation of the beam's polymer concentration. The results show a nearly negligible chemiluminescent effect in the reaction between barium and N20 polymer. A solvated BaO formation mechanism is proposed to justify the experimental results [fr

Isatin derivatives as a non-toxic corrosion inhibitor for mild steel in 20% H2SO4

International Nuclear Information System (INIS)

Ansari, K.R.; Quraishi, M.A.; Singh, Ambrish

2015-01-01

Highlights: • Mild steel protection in 20% H 2 SO 4 by TZs. • Potentiodynamic polarization curves reveal that the actions of TZs are mixed type but cathodically predominant. • The adsorption of TZs obeys the Langmuir adsorption isotherm. • Examination of surface morphology by SEM and EDX. • Correlation between experimental and quantum chemical results. - Abstract: The corrosion inhibition action of Isatin-β-thiosemicarbzone derivatives namely 1-Benzylidene-5-(2-oxoindoline-3-ylidene) Thiocarbohydrazone (TZ-1) and 1-(4-Methylbenzylidene)-5-(2-oxoindolin-3-ylidene) Thiocarbohydrazone (TZ-2) was studied on mild steel surface in 20% H 2 SO 4 by gravimetric measurements, Electrochemical measurements (EIS and Tafel), SEM, EDX and quantum chemical methods. Potentiodynamic polarization curves reveal that the TZs act as mixed type inhibitors exhibiting predominantly cathodic behavior. The adsorption of TZs obeys the Langmuir adsorption isotherm. The thermodynamic parameters (E a , K ads , ΔG° ads ) were also computed and discussed

Influence of crystallization conditions on formation and distribution of nonmetallic inclusions in steels

International Nuclear Information System (INIS)

Efimov, V.A.

1977-01-01

The processes were studied of the formation and the distribution of nonmetallic inclusions and the chemical inhomogeneity formation during the solidification of h steel. The variation of the character of oxides and sulfides across ingots was shown by considering st 25 and 20 Kh steels. To improve the distribution of inclusions and the stability of properties throughout the body of ingots, it is recommended to throughly deoxidize the metal, to raise the rate of solidification, to reduce the temperature gradient, to employ powder cooling agents, to use casting under a blanket of slag, to modify steel by active elements (r.e.e., Ca, Ba, Zr, B) which affect favourably the nature and the shape of the nonmetallic phase

Experience manufacturing and properties of the high-strength corrosion-resistant magnetic 03Kh12K12D2 steel

International Nuclear Information System (INIS)

Fel'dgandler, Eh.G.; Moshkevich, E.I.; Bakuma, S.F.; Bulat, S.I.; Tikhonenko, V.D.

1976-01-01

In industrial conditions, steel 03Kh12K12D2 (DI48-VD) was melted in a 7-tinduction furnace with subsequent vacuum arc remelting. Ingots of dia 500 and 630 mm were forged into slabs and forgings. The slabs were rolled into sheets, 40 mm thick, and the forgings were rolled into sectional shapes. To obtain the optimum mechanical, corrosion, and magnetic properties, the metal was annealed at 600 deg C (10 hr) and 650 deg C (5 and 10 hr). The developed melting and remelting process enabled to obtain steel meeting all the requirements as for the chemical composition, workability, and mechanical magnetic properties. On testing in water with high parameters (200 deg C, 16 kgf/cm 2 ) and in synthetic sea water (70-90 deg C) the corrosion rate did not exceed 1 μm per year

Quality of structural steel melted by single-slag process

International Nuclear Information System (INIS)

Levin, A.M.; Andreev, V.I.; Monastyrskij, A.V.; Drozdova, M.F.; Pashchenko, V.E.; Orzhekh, M.B.

1982-01-01

The 40Kh and 12KhN3A steels were used to compare the quality of the metal manufactured according to several variants of a single-slag process with the metal of a conventional melting technology. Investigation results show, that a single-slag process metal has higher sulfides and oxides contents as well as an increased anisotropy of mechanical properties while its tendency to flake formation is weaker due to a less degree of gas saturation. It is marked that anisotropy in the properties and a sulfide content may be decreased by out-of-furnace treatment of steels

Control of activation levels to simplify waste management of fusion reactor ferritic steel components

International Nuclear Information System (INIS)

Wiffen, F.W.; Santoro, R.T.

1984-01-01

The objective of this work is to examine the restrictions placed on the composition of steels to allow simplified waste management after service in a fusion reactor first wall. Decay of steel activity within tens of years could simplify waste disposal or even permit recycle. For material recycle, N, Al, Ni, Cu, Nb, and Mo must be excluded. For shallow land burial, initial concentration limits include (in at. ppM) Ni, <20,000; Mo, <3650; N, <3650; Cu, <2400; and Nb, <1.0. Other constituents of steels will not be limited

Properties of structural steels melted out of high-purity charge

International Nuclear Information System (INIS)

Marchenko, V.N.; Sergeeva, T.K.; Kondakova, N.K.; Morozov, V.P.; Madorskij, L.L.

1993-01-01

A comparative evaluation has been made of impurities, mechanical properties and hydrogen embirittlement parameters for steels type 40Kh and 40KhS produced by electrometallurgical method with the use of direct reduced charge (DR-steels) and melted in an open-hearth furnace. Investigation results have shown that 40Kh and 40KhS Dr-steels have more coarse austenitic grains and experience more complete transformation of martensite into ferritic-pearlitic mixture on tempering. Threshold stresses increase 2.5 times due to purity enhancement at the expense of application of direct reduced charge

9 CFR 91.20 - General construction.

Science.gov (United States)

2010-01-01

... of construction materials such as wood, metal plate, or pipe may be used for stalls, crates, or pens... accessible to animals. A combination of wood and steel pipe or other steel profile construction may be... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false General construction. 91.20 Section 91...

Effect of hot rolling on the structure and the mechanical properties of nitrogen-bearing austenitic-martensitic 14Kh15AN4M steel

Science.gov (United States)

Bannykh, O. A.; Betsofen, S. Ya.; Lukin, E. I.; Blinov, V. M.; Voznesenskaya, N. M.; Tonysheva, O. A.; Blinov, E. V.

2016-04-01

The effect of the rolling temperature and strain on the structure and the properties of corrosionresistant austenitic-martensitic 14Kh15AN4M steel is studied. The steel is shown to exhibit high ductility: upon rolling in the temperature range 700-1100°C at a reduction per pass up to 80%, wedge steel specimens are uniformly deformed along and across the rolling direction without cracking and other surface defects. Subsequent cold treatment and low-temperature tempering ensure a high hardness of the steel (50-56 HRC). Austenite mainly contributes to the hardening upon rolling in the temperature range 700-800°C at a reduction of 50-70%, and martensite makes the main contribution at higher temperatures and lower strains. Texture does not form under the chosen deformation conditions, which indicates dynamic recrystallization with the nucleation and growth of grains having no preferential orientation.

The effects of adding molybdenum and niobium on the creep strength of 18Cr-10Ni-20Co austenitic steel

International Nuclear Information System (INIS)

Tomono, Yutaka

1987-01-01

The decrease in the creep strength of structural materials during service at elevated temperatures is a very important problem that affects the security of plants and machinery. The improvement in the creep strength of 18Cr-10Ni-20Co austenitic steel achieved through the addition of molybdenum and niobium was studied in tests carried out at 973K and 1,073K. The creep strengthening mechanism was examined using transmission electron micrographs, X-ray diffraction, etc. The results obtained are summarized as follows: (1) The creep strength of low C-18Cr-10Ni-20Co austenitic steel with molybdenum was greatly improved by the addition of niobium up to 1% by weight. In the case of long-term creep, no trend toward decreasing creep strength was observed. (2) The creep strength of austenitic steel possessing a matrix strengthened with molybdenum can be improved through the addition of niobium combined with precipitation hardening with fine carbides precipitated in the grains. (author)

The merging of the islands of inversion at N=20 and N=28

CERN Document Server

Caurier, Etienne; Poves, Alfredo

2014-01-01

The N=20 and N=28 "islands of inversion" are described by large scale shell model calculations with an extension of the interaction sdpf-u that makes it possible to mix configurations with different Nhw or equivalently with different number of particles promoted from the sd-shell to the pf-shell. It allows to connect the classical sd-shell calculations below N=18 with the sd(protons)-pf(neutrons) calculations beyond N=24-26, for all the isotopes from Oxygen to Calcium, using the same interaction. For some isotopes this range contains all the nuclei between the proton and the neutron drip lines and includes the N=20 and N=28 islands of inversion. We shall pay particular attention to the properties of the states at fix Nhw which turn out to be the real protagonists of the physics at N=20. The existence of islands of inversion/deformation will be explained as the result of the competition between the spherical mean field which favors the 0hw configurations and the nuclear correlations which favor the deformed Nh...

Precipitation in 20 Cr-25 Ni type stainless steel irradiated at low temperatures in a thermal reactor (AGR)

International Nuclear Information System (INIS)

Taylor, C.

1983-01-01

The effects of irradiation on the microstructure of AGR fuel rod cladding have been studied by analytical electron microscopy. Two alloys were investigated, the standard 20 Cr-25 Ni steel stabilised with Nb and a variant containing less Nb but strengthened with a dispersion of TiN precipitates. Irradiation at 360 deg C to 480 deg C produced (Ni, Si)-rich precipitates in both alloys; additionally the standard alloy contained (Ni, Nb, Si)-rich precipitates when irradiated at 440 deg C to 640 deg C. While similar features have been observed in other austenitic stainless steels irradiated in fast reactors, where the lattice-damage rate is greater than in a thermal reactor, their formation is not predicted by isothermal equilibrium diagrams. It is suggested here that the phases are irradiation-induced and that the total displacement damage is the controlling factor. Cladding solution-treated above 1050 deg C then irradiated at 2 -based reactor coolant occurred in cladding with low levels of cold-work at the outer surface, also resulting in Cr-rich carbide formation. (author)

Investigation of Creep Processes and Microdamages in 10Kh9V2MFBR-Sh High-Chromium Steel

Science.gov (United States)

Grin', E. A.; Pchelintsev, A. V.

2018-01-01

During the modernization and the new construction of power units at TPPs in Russia, high-chromium martensitic steels with higher heat-resistant properties than the traditional perlite steels are increasingly used as structural materials. High-chromium steels have a necessary regulatory support for their use in domestic power engineering. However, up to the present time, the issue of assessing the quality of these steels at the analysis of their state during long-term operation remains open. The article proposed is one of the first attempts to create a system of quality criteria for martensitic steels based on their microdamage parameters. Tests were carried out on the long-term strength and creep of samples from 10Kh9V2MFBR-Sh steel at high temperatures with the construction of creep curves in relative coordinates "deformation related to the deformation of fracture, current time related to time to failure." For some samples, the tests were interrupted and the metal was subjected to metallographic studies consisting of the analysis of microdamage with reference to the accumulated creep strain. It has been shown experimentally that the deformation curve of high-chromium steel differs from the analogous curve of pearlitic steel by a longer and flat section of steady creep and by a sharper transition to the third accelerated creep stage, which has a very short time period (approximately 10% of the total durability). The tendency to the increase in the microdamage of the structure of steel as the accumulated creep strain increases with time was confirmed. The beginning of transition to the final creep phase is characterized by the formation of contours of future pore chains and by the appearance of individual large pores of up to 6 μm in size, the presence of which in the microstructure of the martensitic steel indicates a very significant accumulation of creep strain, and corresponds to the predestruction stage of metal. It is necessary to continue the research to

On the low-cycle fracture of chromium-nickel-molybdenum structural steels in seawater

International Nuclear Information System (INIS)

Karpenko, G.V.; Kobzaruk, A.V.; Malyshevskij, V.A.; Shul'te, A.Yu.; Rybin, V.V.; Silaev, I.I.

1977-01-01

The processes of low-cycle fracture of the chrome-nickel-molybdenum steels 15KhN5MF, 12KhN4MF and 15KhN3M in air, and in sea water have been investigated by the optical microscopy method, and electron microscopic examination of thin films. Bringing no change in the fracture character, sea water produces a speeding-up effect on the low-cycle fatigue fracture process. During long-time corrosion fatigue testing considerable importance lies with the electrochemical corrosion factor expediting the occurrence of corrosive pits acting as crack-initiation nuclei, fatigue crack attack, accumulation of corrosion products in fatigue cracks, etc

Formación de usuarios de la información mediante aplicaciones Web 2.0

Directory of Open Access Journals (Sweden)

Eder Ávila Barrientos

2015-04-01

Full Text Available Objetivo: Analizar las aplicaciones web 2.0 para estimar su utilización en los programas de formación de usuarios de la información. Método: Análisis documental y la hermenéutica del discurso aplicados a los documentos impresos y digitales que abordan la temática del objeto de estudio. Resultados: se responden una serie de cuestionamientos relacionados con la integración de las aplicaciones Web 2.0 en el diseño de programas de formación de usuarios de la información. En lo que respecta a la selección de aplicaciones web 2.0, se empleo la técnica de análisis de atributos basada en las variables de uso didáctico. Concluisones: Las tecnologías de la web 2.0 y su integración en los programas de formación de usuarios de la información, representan un nicho de oportunidad para los bibliotecólogos. Una oportunidad para alcanzar el futuro y romper viejos paradigmas de la formación de usurios.

Surface finishing and levelling of thermomechanically hardened rolled steel

International Nuclear Information System (INIS)

Grosval'd, V.G.; Bashchenko, A.P.; Grishkov, A.I.; Gutnik, M.V.; Kanevskij, B.L.; Nikozov, A.I.; Sedov, N.D.; Prosin, K.A.; Safonov, L.I.

1975-01-01

The finishing of high-strength merchant shapes from alloy steel was tried out under industrial conditions with the equipment of metallurgical plants. After thermomechanical hardening in the production line of the rolling mill, 30KhGSN2A and 40Kh1NVA steel rounds 32 and 31 mm in diameter were straightened on a two-roller straightening machine designed by the All-Union Scientific Research Institute for Metallurgical Machinery (VNII Metmash). This made possible subsequent turning and grinding of the rods. The conditions of straightening, turning and grinding have been worked so as to obtain thermomechanically strengthened and ground rolled products approximating the gauged and ground metal in shape geometry and surface finish. It is shown that the labour-consuming operation of turning can be eliminated by reducing the machining pass of the rolled product, and this lowers the labour required for the finishing operations by 75%. After grinding with 40- and 25-grain abrasive wheels, high strength rolled shapes were obtained with a diameter of 30-0.20 mm and a surface finish of class 6-5 satisfying the technical specifications. (author)

Manufacturing of ultra-large diameter 20 MnMoNi 5 5 steel forgings for reactor pressure vessels and their properties

International Nuclear Information System (INIS)

Onodera, S.; Kawaguchi, S.; Tsukada, H.; Moritani, H.; Suzuki, K.; Sato, I.

1985-01-01

As the structural material for RPV typical of increased dimensions, as set of ultra-large diameter steel forgings for a PHWR RPV is presented as outlined below. (1) Material designation: 20 MnMoNi 5 5 (similar to SA508, Cl.3) (2) Size of the forgings: flanges, 8.440 mm OD, a weight of 238 tons for shell flange; shells and torus, 7,920 mm OD, with large height, cover dome, 6,800 mm OD in chord and 460 mm thick; blank before formed to dome is ca. 8,000 mm OD. (3) Chemical composition: particular effort was made for minimizing the tramp elements as P, S, As, Sn, Sb, Cu. (4) Manufacturing, key points: steel making - combined refining and degassing in ladle; ingot making - largest size ingots, including 570 ton and 500 ton ingots; forging - special ''outside-the-press'' forging and forming techniques; heat treatment - prevention of H 2 flaking in normalizing and tempering and handling of the extra-large forgings at water quenching. (5) Metallurgical properties: sufficiently uniform carbon distributions in the forgings; a lowest possible content of hydrogen, non-metallic inclusions and oxygen. Mechanical properties: uniformity in tensile and toughness properties; flaws - only limited number of spots of UT indications under 2 mm EFG (EFS). (orig.)

Improving composition of protective coatings for steel casting

International Nuclear Information System (INIS)

Kuz'kina, N.N.; Pegov, V.G.; Bogatenkov, V.F.; Shub, L.G.; Raspopova, N.A.

1983-01-01

A radically new fuel-free slag-forming mixture used as protective coating for steel casting is introduced. The lack of combustible powders precludes explosion and fire Lazard in mixture preparation. Usage of the new mixture in stainless steel casting of Kh18N10T type permitted to improve the ingot surface quality and reduce spoilage from 1.16 to 0.66%

Topic 1. Steels for light water reactor pressure vessels

International Nuclear Information System (INIS)

Brumovsky, M.; Brynda, J.; Kepka, M.; Barackova, L.; Vacek, M.; Havel, S.; Cukr, B.; Protiva, K.; Petrman, I.; Tvrdy, M.; Hyspecka, L.; Mazanec, K.; Kupca, L.; Brezina, M.

1980-01-01

Part 1 of the Proceedings consists of papers on the criteria for the selection and comparison of the properties of steel for pressure vessels and on the metallurgy of the said steels, the selection of suitable material for internal tubing systems, the manufacture of high-alloy steels for WWER components, the mechanical and metallurgical properties of steel 22K for WWER 440 pressure components, and of steel 10MnNi2Mo for the WWER primary coolant circuit, and the metallographic assessment of steel 0Kh18N10T. (J.P.)

Effect of cyclic electron irradiation on mechanical properties of austenite steel

International Nuclear Information System (INIS)

Tsepelev, A.B.; Sadykhov, S.I.O.; Chernov, A.I.; Sevost'yanov, M.A.

2006-01-01

To check the supposition on the possibility of radiation-stimulated process enhancement under cyclic irradiation conditions an experimental investigation is carried out to elucidate the effect of the mode of irradiation (continuous or cyclic) on mechanical properties of chromium-manganese austenitic stainless steel type 10Kh12G20V. The effect of some radiation hardening is observed under cyclic irradiation, however, the data obtained cannot be considered as good evidence for the validity of proposed model of dynamic preference if the scatter in experimental data is taken into account [ru

The influence of cerium and yttrium ion implantation upon the oxidation behaviour of a 20% Cr/25% Ni/Nb stabilised stainless steel, in carbon dioxide, at 8250C

International Nuclear Information System (INIS)

Bennett, M.J.; Dearnaley, G.; Houlton, M.R.; Hawes, R.W.M.

1982-01-01

The influence of cerium and yttrium ion implantation upon the oxidation behaviour of a 20% Cr/25% Ni niobium stabilised stainless steel during up to 7 157h exposure to carbon dioxide, at 825 0 C has been examined. The doses ranged between 5 x 10 14 and 10 17 ions cm -2 . Above thresholds of between 5 x 10 14 and 5 x 10 15 yttrium and between 5 x 10 15 and 10 16 cerium ions cm -2 the implantation of both elements improved the oxidation resistance of the 20/25/Nb steel. Yttrium exerted the greater influence, reducing by a factor of two the attack after 7 157h. Up to 80% of the oxide formed on the 20/25/Nb steel spalled, particularly on thermal cycling. Cerium and yttrium implantation improved oxide adhesion by similar extents, which increased with ion dose such that with the highest doses, no spallation was measurable. The effect of the implanted elements derived from their incorporation within the oxide film. It was initiated by their promotion of the formation of an initial chromium-rich oxide layer, which had a finer grain size than that formed on the 20/25/Nb steel. Reduction in continuing attack was associated in part, with improved oxide adhesion, as this decreased the significant contribution to the attack of the 20/25/Nb steel from the reoxidation of spalled areas. (author)

Herramientas colaborativas para la Gestión del Conocimiento en la Universidad 2.0 (Collaborative tools for Knowledge Management at the University 2.0

Directory of Open Access Journals (Sweden)

Laidy De Armas Jacomino

2016-03-01

Full Text Available Spanish abstract En el contexto empresarial se presentan a diario múltiples problemas que ya han sido resueltos por otras personas anteriormente. Además se buscan informaciones en el exterior cuando la empresa cuenta con expertos en la materia que pudieran contribuir con su conocimiento y aportar a su capital intelectual. Estas situaciones se evidencian de forma particular en las universidades ya que confluyen diversas ciencias y sectores. Para evitar esto se comienza a implementar la Filosofía 2.0, que evita que se pierda el conocimiento organizacional facilitando la colaboración para compartir información, contactos y recursos entre sus miembros. En el caso de las universidades se acuña el término Universidad 2.0 que está asociado en gran medida al uso de herramientas y conceptos colaborativos de la Web 2.0 en sus procesos formativos y empresariales. Estas herramientas se encuentran enfocadas principalmente en las personas y en brindarles la posibilidad de socializar lo que saben convirtiéndose en participantes activos en la construcción y divulgación de nuevo conocimiento. En el presente trabajo se abordan los términos Web 2.0, Empresa 2.0 y Universidad 2.0, así como la marcada relación entre ellos. Además se da a conocer la evolución de la universidad hacia el trabajo colaborativo a través de la Web. Se muestran también herramientas colaborativas que apoyan la Gestión del Conocimiento en la Universidad 2.0. Por último, se proponen un grupo de ideas para la implantación de la Gestión del Conocimiento a través de herramientas colaborativas de la Web en una universidad cubana. English abstract In business context recurrent problems appear. In addition, information outside the organization are searched when the company has experts in the field who could contribute their knowledge and intellectual capital. These situations are particularly evident in the universities which converge various sciences and sectors. To avoid

Construcción de un cuestionario para la evaluación de la gratitud: el Cuestionario de Gratitud-20 ítems (G-20

Directory of Open Access Journals (Sweden)

Gloria Bernabé-Valero

2014-01-01

Full Text Available Se desarrolló una escala para la medición de la gratitud. Un banco inicial de 50 ítems, construidos y revisados siguiendo criterios precisos, se administró a 330 universitarios españoles (242 mujeres, 72.5%; 88 hombres, con edades comprendidas entre 18 y 43 años, M = 23.33, DT = 4.87. Un Análisis Factorial Exploratorio dio lugar a una solución terminal de 20 ítems con una estructura interna de 4 factores, que se denominó Cuestionario de Gratitud-20 Ítems. Un Análisis Factorial Confirmatorio sobre la matriz de correlaciones policóricas mostró un adecuado ajuste de la escala. La escala y las componentes presentaron consistencia interna entre aceptable y alta. La validez concurrente se comprobó mediante correlación de Pearson con la escala Gratitude Questionnaire-Six Item Form, y la validez discriminante mediante análisis confirmatorio de factores latentes con el Purpose-In-Life Test. Los resultados obtenidos indicaron que las dimensiones del Cuestionario de Gratitud-20 Ítems pueden estar estrechamente relacionadas con la gratitud.

Fouling and biocorrosion of a high-alloy steel in the Golden Horn bay

International Nuclear Information System (INIS)

Koryakova, M.D.; Nikitin, V.M.; Suponina, A.P.; Kharchenko, U.V.; Zvyagintsev, A.Yu.

2002-01-01

The studies on the effect of contamination of the Golden Horn bay waters (the Peter the Great Bay in the Japanese Sea) on formation of the community of the bacterio- and macrofouling and corrosion resistance of the Kh18N10T high-alloy steel are continued. The dissolved and chemically absorbed oxygen, pH, saprophytes, oil-oxidizing, sulfate-reducing bacteria and heavy metals are among the medium indicators, characterizing the level of pollution of the regions of the samples testing. It is shown, that the obtained experimental data extend our understanding of the dependent effect of three factors: the sea medium → fouling → corrosion resistance of the Kh18N10T high-alloy steel [ru

The effect of chromium diffusion redistribution on wear resistance of carburized 3Kh13 steel

International Nuclear Information System (INIS)

Shcherbedinskij, G.V.; Shumakov, A.I.; Zemskij, S.V.; Pereverzev, V.M.

1977-01-01

The redistribution of chromium in steel 3Kh13 on carburization in a high-activity carburizer and the wear-resistance of the steel have been investigated. Surface layers with an increased chromium concentration show the highest wear-resistance. The chromium content in the surface layer increases due to its diffusion from the interior. The distribution of carbon and chromium in the carburized layers has been studied with the aid of the radioactive isotope 14 C by the method of layer-by-layer spectral analysis on a vacuum quantometer, layer-by-layer chemical and X-ray structure analysis. The composition of the carbides has been determined by physicochemical analysis. It has been established that the carburized layer can be divided into four zones with respect to its phase composition: first zone - hematite and spinal with 0.5-2.0% C; second zone - solid carbides (Fe,Cr) 7 C 3 ; up to 5% C; third zone - globular carbides in a troostite matrix (Cr,Fe) 7 C 3 and Cr 23 C 6 ; up to 3.5% C; fourth, transitional, zone - troostite carbide mixture Cr 23 C 6 ; up to 1% C. The chromium diffusion in the carburized layer is faster than in the initial austenite. The chromium counterdiffusion is due to the development of a zone of solid carbides M 7 C 3

Structure of boron clusters revisited, Bn with n = 14-20

Science.gov (United States)

Tai, Truong Ba; Tam, Nguyen Minh; Nguyen, Minh Tho

2012-03-01

We reinvestigate the structures of neutral boron clusters Bn, with n = 14-20. G3B3 calculations confirm that a transition between 2D and 3D shape occurs at B20, which has a tubular form. In disagreement with Boustani et al. (Phys. Rev. B, 83 (2011) 193405), we find a planar B19 cluster. Standard heats of formation are obtained and used to evaluate the clusters stability. The average binding energy tends to increase with increasing size toward a limit. Higher stability is found B14, B16, B18 and B20. All Bn have negative NICS-values. The bonding nature and electron delocalization of B20 are re-examined using CMO and LOL.

Heating temperature effect on ferritic grain size of rotor steel

International Nuclear Information System (INIS)

Cheremnykh, V.G.; Derevyankin, E.V.; Sakulin, A.A.

1983-01-01

The heating temperature effect on ferritic grain size of two steels 13Kh1M1FA and 25Kh1M1FA is evaluated. It is shown that exposure time increase at heating temperatures below 1000 deg C up to 10h changes but slightly the size of the Cr-Mo-V ferritic grain of rotor steel cooled with 25 deg C/h rate. Heating up to 1000 deg C and above leads to substantial ferritic grain growth. The kinetics of ferritic grain growth is determined by the behaviour of phases controlling the austenitic grain growth, such as carbonitrides VCsub(0.14)Nsub(0.78) in 13Kh1M1FA steel and VCsub(0.18)Nsub(0.72) in 25Kh1M1FA steel. Reduction of carbon and alloying elements content in steel composition observed at the liquation over rotor length leads to a certain decrease of ferritic grain resistance to super heating

High-cycle fatigue characteristics of weldable steel for light-water reactors

International Nuclear Information System (INIS)

Klesnil, M.; Polak, J.; Obrtlik, K.; Troshchenko, V.T.; Mishchenko, Yu.I.; Khamaza, L.A.

1982-01-01

Czechoslovak and Soviet 15Kh2NMFA steel was used for running fatigue tests at temperatures of 20, 350 and 400 degC in the high-cycle range with various loading regimes. The results show that at the given temperatures in this type of steel a cyclic softening occurs. The fatigue characteristics were measured with great dispersion of results, but within this dispersion they are almost identical for various steels at the same temperature. Increased temperature results in the decrease in the amplitude of cyclic deformation stress and in the increase in the amplitude of plastic deformation. The diversity in the values of cyclic plasticity and stress response measured in the given mode may be explained by the lower level of softening and the non-homogeneous cyclic plastic deformation of material under the given constant conditions. (J.B.)

Effect of neutron irradiation on the properties of the repair welds of the 15Kh2MFA steel

International Nuclear Information System (INIS)

Morozov, A.M.; Khachaturyants, L.V.

1986-01-01

The authors studied the effect of neutron irradiation on the tendency of the metal belonging to the heat affected zone of the weld toward brittle fracture (an increase in the critical temperature of brittleness). For comparison, the authors studied the radiation embrittlement of the original base metal (steel 15Kh2MFA) subjected to the conventional heat treatment of the reactor frames consisting of hardening and high-temperature tempering. Along with these materials, the radiational embrittlement of the base metal in the rehardened condition without tempering was studied. It was concluded that the presence of the regions repaired according to this technology and located in the frame at the level of the reactor core does not pose the problem of decreased resistance to brittle fracture

Behaviour of glass and thermal protective coatings on stainless steels in the nitrogen tetroxide based coolant

International Nuclear Information System (INIS)

Bakalin, Yu.I.; Dobrunova, V.M.; Doroshkevich, V.N.; Nesterenko, V.B.; Trubnikov, V.P.

1985-01-01

The technology of application of glass and enamel protective coatings on stainless steel has been examined, their testing in the medium of nitrogen tetroxide based coolant with different content of nitric acid has been carried out, the basic characteristics of the coatings after testing have been defined. Chromium-nickel austenitic 12kh18n10t steel, widely used in the nuclear power, have been chosen as a basic object of examination. The coatings have been tested in nitrogen oxide at P=12.0 MPa, temperature 310 deg C and 0.1% HNO 3 , and also in the medium of vat residue of the rectifying tower with nitric acid content up to 25 mass %. Tests of the coatings have demonstrated their sufficiently high stability, especially of those based on enamels A-20 and BK-5. These coatings are characterised by satisfactory performance and can be used for corrosion protection of the materials used in nuclear power

Study of the damage processes induced by thermal fatigue in stainless steels F17TNb and R20-12 for automobile application; Etude de l'endommagement en fatigue thermique des aciers inoxydables F17TNb et R20-12 pour application automobile

Energy Technology Data Exchange (ETDEWEB)

Bucher, L.

2004-12-15

Thermal cycling is the main cause of fatigue failure in automobile exhaust manifolds for which the use of stainless steel now rivals that of cast iron which has been traditionally used. An original fatigue test has been developed by Ugine and ALZ, a stainless steel producer, so as to be able to compare different grades of stainless steel alloys. This test is representative of the thermal conditions encountered in the critical zones of exhaust manifolds. However, it has revealed significant differences in damage processes in the ferritic and austenitic grades tested. The subject of this thesis is the damage processes induced by thermal fatigue in stainless steels used for automotive exhaust manifolds. Two stainless steels were studied: a ferritic grade, F17TNb (17%Cr and stabilized with Ti and Nb), and an austenitic grade, R20-12, containing 20% Cr and 12% Ni. The first objective was to understand the different damage processes induced by thermal fatigue in the ferritic and austenitic grades. The second was to develop a numerical design tool of the thermally tested structures. (author)

Annealing effect on restoration of irradiation steel properties

International Nuclear Information System (INIS)

Vishkarev, O.M.; Kolesova, T.N.; Myasnikova, K.P.; Pecherin, A.M.; Shamardin, V.K.

1986-01-01

The effect of temperature and annealing time on the restoration of properties of the 15Kh2NMFAA and 15Kh2MFA steels after irradiation at 285 deg with the fluence of 6x10 23 neutr/m 2 (E>0.5 MeV) is studied. Microhardness (H μ ) restoration in the irradiated 15Kh2NMFAA steel is shown to start from 350 deg C annealing temperature. The complete microhardness restoration is observed at the annealing temperature of 500 deg C for 10 hours

Growth of (20 anti 21)AlGaN, GaN and InGaN by metal organic vapor phase epitaxy

Energy Technology Data Exchange (ETDEWEB)

Ploch, S.; Wernicke, T.; Rass, J.; Pristovsek, M. [TU Berlin, Institut fuer Festkoerperphysik, Hardenbergstr. 36, 10623 Berlin (Germany); Weyers, M. [Ferdinand-Braun-Institut, Leibniz Institut fuer Hoechstfrequenztechnik, Gustav-Kirchhoff-Str. 4, 12489 Berlin (Germany); Kneissl, M. [TU Berlin, Institut fuer Festkoerperphysik, Hardenbergstr. 36, 10623 Berlin (Germany); Ferdinand-Braun-Institut, Leibniz Institut fuer Hoechstfrequenztechnik, Gustav-Kirchhoff-Str. 4, 12489 Berlin (Germany)

2012-07-01

Green InGaN-based laser diodes on (20 anti 21)GaN substrates have recently demonstrated performances exceeding those of conventional (0001) oriented devices. However little is known regarding the growth parameters. We have investigated growth of AlGaN, GaN and InGaN on (20 anti 21)GaN substrates by MOVPE. Smooth GaN layers with a rms roughness <0.5 nm were obtained by low growth temperatures and reactor pressures. The layers exhibit undulations along [10 anti 14] similar to the GaN substrate. AlGaN and InGaN layers exhibit an increased surface roughness. Undulation bunching was observed and attributed to reduced adatom surface mobility due to the binding energy of Al and the low growth temperature for InGaN respectively or strain relaxation. AlGaN and InGaN heterostructures on (20 anti 21)GaN relax by layer tilt accompanied by formation of misfit dislocations, due to shear strain of the unit cell. This relaxation mechanism leads to a reduced critical layer thickness of (20 anti 21)AlGaN layers and InGaN multi quantum wells (MQW) in comparison to (0001). PL spectral broadening of 230 meV of (20 anti 21)InGaN single QWs emitting at 415 nm can be reduced by increased growth temperature or increased number of QWs with reduced thickness.

Methods for protection of high-strength welded stainless steel from corrosion cracking

International Nuclear Information System (INIS)

Lashchevskij, V.B.; Gurvich, L.Ya.; Batrakov, V.P.; Kozheurova, N.S.; Molotova, V.A.; Shvarts, M.M.

1978-01-01

The efficiency of protection from corrosion cracking under a bending stress of 100 kgf/mm 2 in a salt mist and in a sulphur dioxide atmosphere, of welded joints of steel 08Kh15N5D2T with metallizing, galvanic and varnish coatings and lubricants, and of steel 1Kh15N4AM3 with sealing compounds has been investigated. Metallization of welded joints with aluminium and zinc efficiently increases corrosion resistance in a salt mist. Galvanic coatings of Cd, Zn, and Cr increase the time to cracking in a salt mist from 2-3 to 60-80 days. The protective properties of varnishes under the effect of a salt mist decrease in the following sequence: epoxy-polyamide enamel EP-140, acrylic enamel C-38, silicone enamels KO-834, KO-811, and KO-814. In an atmosphere containing SO 2 0.15 vol.% at 100% relative humidity, the varnishes investigated, with the exception of the inhibited coating XC-596, show lower protective properties than in a salt mist. The high efficiency of protection from corrosion cracking in a salt mist of slots of steel 1Kh15N4AM3 when using organic sealing compounds U4-21 and U5-21, and also slushing lubricants and oils PVK, TsIATIM-201, K17, and AMS3 was established

Lamivudine monotherapy-based cART is efficacious for HBV treatment in HIV/HBV co-infection when baseline HBV DNA<20,000IU/ml

Science.gov (United States)

LI, Yijia; XIE, Jing; HAN, Yang; WANG, Huanling; ZHU, Ting; WANG, Nidan; LV, Wei; GUO, Fuping; QIU, Zhifeng; LI, Yanling; DU, Shanshan; SONG, Xiaojing; THIO, Chloe L; LI, Taisheng

2016-01-01

Background Although combination antiretroviral therapy (cART) including tenofovir (TDF)+lamivudine (3TC) or emtricitabine (FTC) is recommended for treatment of HIV/HBV co-infected patients, TDF is unavailable in some resource-limited areas. Some data suggest that 3TC monotherapy-based cART may be effective in patients with low pre-treatment HBV DNA. Methods Prospective study of 151 Chinese HIV/HBV co-infected subjects of whom 60 received 3TC-based cART and 91 received TDF+3TC-based cART. Factors associated with HBV DNA suppression at 24 and 48 weeks, including anti-HBV drugs, baseline HBV DNA, and baseline CD4 cell count, were evaluated overall and stratified by baseline HBV DNA using Poisson regression with a robust error variance. Results Baseline HBV DNA≥20,000 IU/ml was present in 48.3% and 44.0% of subjects in the 3TC and TDF groups, respectively (P=0.60). After 48 weeks of treatment, HBV DNA suppression rates were similar between these two groups (96.8% vs. 98.0% for 3TC and TDF+3TC, P>0.999) in subjects with baseline HBV DNAHBV DNA ≥20,000 IU/ml, TDF+3TC was associated with higher suppression rates (34.5% vs. 72.5% in 3TC and TDF+3TC groups, respectively, P=0.002). In stratified multivariate regression, TDF use (RR 1.98, P=0.010) and baseline HBV DNA (per 1 log increase in IU/ml, RR 0.74, PHBV DNA suppression only when baseline HBV DNA≥20,000IU/ml. Conclusion This study suggests that 3TC monotherapy-based cART is efficacious for HBV treatment through 48 weeks in HIV/HBV co-infection when baseline HBV DNA<20,000IU/ml. Studies with long-term follow-up are warranted to determine if this finding persists. PMID:26745828

32 CFR 537.20 - Certification to Congress.

Science.gov (United States)

2010-07-01

... 32 National Defense 3 2010-07-01 2010-07-01 true Certification to Congress. 537.20 Section 537.20... BEHALF OF THE UNITED STATES § 537.20 Certification to Congress. Admiralty claims, including claims for... of the Army for approval and if in excess of $500,000 for certification to Congress for final...

Geological map of Uruguay Esc 1,100,000. Bequelo Sheet N0-20

International Nuclear Information System (INIS)

Montana, J.; Ford, I.; Morales, H.

1990-01-01

This work is about the geological map of Uruguay Esc.1.100.000 (Bequelo) and the explanatory memoranda which describes the geological , lithological and sedimentological characteristics of the precambrian period in the Bequelo stream as well as the Mercedes , Asencio and Fray Bentos formations

Fatigue resistance of Cr-Ni-Mo-V steel

International Nuclear Information System (INIS)

Naumchenkov, N.E.; Filimonova, O.V.; Borisov, I.A.

1985-01-01

A study was made on the effect of additional alloying (Ni, Ni+Co), stress concentration, surface plastic strain on fatigue resistance of rotor steel of Cr-Ni-Mo-V-composition. It is shown that the steel with decreased carbon content possesses high complex of mechanical properties. Fatigue characteristics are not inferior to similar characteristics of steels of 25KhN3MFA type. Additional alloying of the steel containing 0.11...0.17% C and 4.5...4.7% N:, with niobium separately or niobium and cobalt in combination enabled to improve fatigue resistance of samles up to 25%. Strengthening of stress concentration zones by surface plastic strain is recommended for improving rotor suppporting 'nower under cyclic loading

Increasing the brittle fracture resistance in manual arc welding and heat treatment of type 12KhM steels

International Nuclear Information System (INIS)

Tikhonov, V.P.; Bychenkova, G.A.; Gordeev, Y.V.; Ilyuhov, C.V.

1984-01-01

The extensive application of heat-resisting steels is delayed by their poor weldability. Optimum technology has been developed for manual arc welding and heat treatment of structures of type 12KhM steels resulting in high cracking resistance. Trials were conducted to evaluate the efficiency of removing the structural stresses in tempering the structures. On the basis of the experimental results, it may be assumed that the toughness properties of the welded joints produced by manual arc welding can be improved by optimizing the alloying system of the weld metal, with the parent metal treated in the optimum heat treatment conditions. The aim of subsequent investigations was to assess the properties of the weld metal made with vanadium-free electrodes. It was found that the impact toughness increased two to three times; the mean hardness and the maximum hardness were both less than 220. The reduction in hardness and increase of the toughness properties of the metal are caused by the lower degree of hardening of the bulk of the grain and, consequently, by the lower concentration of plastic strain at the grain boundaries

Rupture of the steel-12KH1MF under creep at temperatures close to 0,5 Tsub(melt)

International Nuclear Information System (INIS)

Berezina, T.G.; Ashikhmina, L.A.; Karasev, V.V.

1976-01-01

Optical and transmission microscopy and fractography techniques have been employed in studying the peculiarities of nucleation and growth of micropores in steel 12Kh1MF at creep. The nucleation of micropores occurs at the initial stages of creep at stress concentration points, predominantly following the retarded shear mechanism. Micropores grow by the way of diffusion, as well as following the deslocation mechanism. An important role in the process of micropore growth is played by pore opening through grain-boundary slip. Pores of 1 to 5 microns in size can be formed along grain boundaries both due to the growth of individual micropores and by coalescence of micropores at points of their concentration. Transition of the creep to the critical phase coincides with the process of the pores blending together to

Study of the closure of the nuclear shells N = 16, 20, 28 and 40; Etudes des fermetures de couches nucleaires N=16, 20, 28 et 40

Energy Technology Data Exchange (ETDEWEB)

Sorlin, O

2005-12-15

There are 2 types of nuclear shell closures: one is associated to a number of the harmonic oscillator, typically N = 20 and 40, and the other is a consequence of the spin-orbital interaction that produces magic numbers such as N = 28, 50, 82 and N = 126. The first part of this work deals with the knowledge accumulated around the closure of the N = 28 shell. 3 means of investigation have been used: -) the study of beta decay nuclei (K{sup 47}, Ar{sup 46}, S{sup 44}, Si{sup 42} and Cl{sup 45}), -) the on-line spectroscopy of nuclei around N = 28, and -) the study of Ar{sup 45} and Ar{sup 47} through transfer reactions. The second part is dedicated to results concerning the nuclear structure of nuclei around N = 14-20 and around N = 40. (A.C.)

Fracture of ledeburitic steel during hot plastic deformation

International Nuclear Information System (INIS)

Nikitin, V.P.; Borisov, Yu.A.; Bulat, S.I.; Zajtsev, V.V.

1977-01-01

The mechanisms of the high-temperature failure of high-carbon chromium Kh6F1, Kh6T2 and Kh6VF steels and a possibility to avoid their overheating have been investigated. At 1190 deg C and over the failure occurs along boundaries of grains at points of formation of the initial portions of the liquid phase as carbides are dissolved. If after a holding at 1190-1210 deg C the steels are cooled to 1120-1150 deg C and held for a sufficiently long time, secondary carbides are formed in the eutectic areas and, if the steels are deformed, the discontinuities present a rounded shape. Holding of an overheated steel at 1120-1150 deg C ensures its satisfactory workability in rolling. By choosing adequate overheating and subsequent slight cooling conditions, it is possible not only to retain, but even to improve the plasticity of carbide high-carbon steels. The results of laboratory tests have been confirmed under industrial conditions

File list: Oth.Lar.20.Adenine_N6-methylation.AllCell [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available Oth.Lar.20.Adenine_N6-methylation.AllCell ce10 TFs and others Adenine N6-methylatio...n Larvae http://dbarchive.biosciencedbc.jp/kyushu-u/ce10/assembled/Oth.Lar.20.Adenine_N6-methylation.AllCell.bed ...

File list: Oth.Adl.20.Adenine_N6-methylation.AllCell [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available Oth.Adl.20.Adenine_N6-methylation.AllCell ce10 TFs and others Adenine N6-methylatio...n Adult http://dbarchive.biosciencedbc.jp/kyushu-u/ce10/assembled/Oth.Adl.20.Adenine_N6-methylation.AllCell.bed ...

Extractive-photometric determination of niobium with N-benzoylphenylhydroxylamine and lumogallion in alloyed steels

International Nuclear Information System (INIS)

Patratij, Yu.V.; Pilipenko, A.T.

1978-01-01

An extractive-photometric method has been developed to determine niobium (5) present as a heteroligand complex with N-benzoylphenylhydroxylamine (BPH) and lumogallion in alloyed steels. The method is based on preliminary extraction of niobium in a complex with BPH from concentrated HCl and subsequent determination of niobium in a 5-n (with respect to HCl) solution with lumogallion added. Sensitivity of the method is 2.0 μg of niobium in 10 ml of extract. The method has been tested on standard steels specimens

Corrosion cracking of 03N18K1M3TYu and 02N12Kh5M3 maraging steels in chloride solutions

Energy Technology Data Exchange (ETDEWEB)

Pavlov, V.N.; Chumalo, G.V.; Vereshchagin, A.N.; Melekhov, R.K.

1987-07-01

The authors investigate the electrochemical behavior in 0.5% NaCl solution and 42% MgCl/sub 2/ solution and the tendency toward corrosion cracking was determined in boiling 0.5% chloride solution of the cobalt-containing maraging steels in the title. Weld specimens and specimens of the base metal of 03N18K1M3TYu steel were tested in 3% NaCl solution for resistance to corrosion cracking. Additional investigations were made of specimens of that steel with previously created fatigue cracks of the base metal and the weld specimens in 3% NaCl solutions, since that steel is a promising material for structures operating in sea water and low concentration chloride solutions.

File list: Oth.ALL.20.Adenine_N6-methylation.AllCell [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available Oth.ALL.20.Adenine_N6-methylation.AllCell ce10 TFs and others Adenine N6-methylatio...n All cell types http://dbarchive.biosciencedbc.jp/kyushu-u/ce10/assembled/Oth.ALL.20.Adenine_N6-methylation.AllCell.bed ...

Web 2.0:n tarjoamien markkinointikeinojen hyödyntäminen Kokemuskauppa.com -verkkokaupassa

OpenAIRE

Oksanen, Katja

2009-01-01

Opinnäytetyön tavoitteena oli selvittää, mitä markkinointikeinoja Web 2.0 -internetkulttuuri tarjoaa elämyksiä tarjoavalle Kokemuskauppa.com -verkkokaupalle ja kehittää yrityksen internetmarkkinointia. Tarkoituksena oli hyödyntää erilaisia Web 2.0:n tarjoamia internetmarkkinointikeinoja ja tutkia, kuinka tehdyt toimenpiteet vaikuttivat Kokemuskauppa.com:n sivujen kävijämääriin. Tutkimuskysymyksiksi muotoutui miten Web 2.0 tarjoamat markkinointikeinot vaikuttivat Kokemuskauppa.com:n kävijämäär...

Boron effect on fabrication properties and service behaviour of complex corrosion-resistant steels

International Nuclear Information System (INIS)

Gol'dshtejn, Ya.E.; Piskunova, A.I.; Shmatko, M.N.

1978-01-01

In order to determine the optimum boron admixtures for the improvement of the technological plasticity without the considerable reduction in the corrosion resistance of the complex alloy Cr-Ni-Mo steels, industrial heats of the 03KH16N15M3, 03KH17N14M3 and other steels, containing 0.0005-0.003% boron, have been researched. The plasticity, corrosion resistance and microstructure of certain steels have been determined. It is shown that small additions of boron enhance the technological plasticity during the ingot rolling. In order to prevent a sharp reduction in the corrosion resistance, the boron content should be confined to 0.0015% and the quenching temperature raised to 1,120-1,150 deg C. The positive effect of the quenching temperature increase is accounted for by the solution of the excess phases and by the reduction of the dislocation density in the near-the-boundary zones

Influence of heating temperature on bainite transformation proceeding in chromium-nickel-molybdenum steels

International Nuclear Information System (INIS)

Kaletin, Yu.M.; Kaletin, A.Yu.

1983-01-01

The purpose of the present paper is to investigate the effect of heating and cooling from austenization temperature on development of bainite transformation in 37KhN3MFA and 18Kh2N4MA structural alloyed steels. The metallographical analysis of specimens has revealed that first crystals of bainite under slow heating up to 770-790 deg C appear at the temperature of about 500 deg C and at 475 deg C there has been much bainite over the whole cross section of the specimen. It is revealed that an increase of heating temperature and cooling rate replace the starting point of bainite transformation upwards. The strongest displacement of the point Bsub(S) into hogh-temperature range takes place after heating steel with the initial bainite structure in intercritical temperature range

N2 vs H20 as purge/hydrostatic head

International Nuclear Information System (INIS)

Mast, J.C.

1996-01-01

This document provides the information to explain to the customer the ETP for the N2 vs H20 as Purge/Hydrostatic Head. This ETP follows the format described in Issurance of New Characterization Equipment Engineering Desk Instructions, 75200-95-013

Microscopical investigation of steamside oxide on X20CrMoV121 superheater tubes

DEFF Research Database (Denmark)

Montgomery, Melanie; Hansson, Anette Nørgaard; Jensen, Søren A.

2011-01-01

X20CrMoV121 is a 12%Cr martensitic steel which has been used in power plants in Europe for many decades. Superheater tubes exposed for various durations up to 135,000 hours in power plants in Denmark at steam temperatures varying from 450 to 575°C were investigated. Light optical and scanning ele...... electron microscopy was used to investigate steamside oxide morphologies. At all temperatures there is a double layered oxide, however, the inner:outer oxide thickness is not always equal. At the lower steam temperature range of...

Strength of low-carbon rotor steel

International Nuclear Information System (INIS)

Voropaev, V.I.; Filimonov, O.V.; Borisov, I.A.

1988-01-01

The results of studying the effect of chemical composition and thermal treatment regimes on the structural strength of steels of the 25KhN3MFA type are presented. It is shown that alloying with niobium from 0.01 to 0.08% steels with the increased nickel content (4.2-4.5%) contributes to the increase of structural strength and reduction of semibrittleness temperature. To obtain high values of strength and plastic properties cooling with the rate of 10 3 -10 5 K/hr is recommended

Dependence of irradiation creep on temperature and atom displacements in 20% cold worked type 316 stainless steel

International Nuclear Information System (INIS)

Gilbert, E.R.

1976-04-01

Irradiation creep studies with pressurized tubes of 20 percent cold worked Type 316 stainless steel were conducted in EBR-2. Results showed that as atom displacements are extended above 5 dpa and temperatures are increased above 375 0 C, the irradiation induced creep rate increases with both increasing atom displacements and increasing temperature. The stress exponent for irradiation induced creep remained near unity. Irradiation-induced effective creep strains up to 1.8 percent were observed without specimen failure. 13 figures

Corrosion of stainless steel in alcohol solutions of the simplest carboxylic acids

International Nuclear Information System (INIS)

Vigdorovich, V.I.; Korneeva, T.V.; Tsygankova, L.E.

1975-01-01

The behaviour of stainless Kh18N10T steel is considered in the methanol and ethanol solutions of formic and acetic acids, respectively. Consideration is given to the effect of the concentration (C) of the acid (0.01-1.00 N), water (0.1-20.0 mass.%) and temperature (room temperature, 40 and 60 deg C). Curves of anodic polarization were plotted. In the course of time in 1.0 and 0.5 N anhydrous methanol solutions of HCOOH at room temperature in the absence of the external anode current one can observe an increase in the electrode potential. Continued reduction of the formic acid concentration results in an improvement on the initial potential (psi) and a practical constancy of psi in time. It is shown that depending on the acid concentration the additions of water are capable of producing both a passivating and an activating effect. It is assumed that the growth in the length of the hydrocarbon radical of carboxylic acid promotes the adsorption displacement of water and alcohols from the metal surface and enhancement of the corrosion rate

SCC growth behavior of cast stainless steels in high-temperature water. Influences of corrosion potential, steel type, thermal aging and cold-work

International Nuclear Information System (INIS)

Yamada, Takuyo; Terachi, Takumi; Miyamoto, Tomoki; Arioka, Koji

2011-01-01

Recent studies on crack growth rate (CGR) measurement in oxygenated high-temperature pure water conditions, such as normal water chemistry (NWC) in BWRs, using compact tension (CT) type specimens have shown that stainless steel weld metal are susceptible to stress corrosion cracking (SCC). On the other hand, the authors reported that no significant SCC growth was observed on stainless steel weld metals in PWR primary water at temperatures from 250degC to 340degC. Cast austenitic stainless steels are widely used in light water reactors, and there is a similarity between welded and cast stainless steels in terms of the microstructure of the ferrite/austenite duplex structure. However, there are a few reports giving CGR data on cast stainless steels in the BWRs and PWRs. The principal purpose of this study was to examine the SCC growth behavior of cast stainless steels in simulated PWR primary water. A second objective was to examine the effects on SCC growth in hydrogenated and oxygenated water environments at 320degC of: (1) corrosion potential; (2) steels type (Mo in alloy); (3) thermal-aging (up to 400degC x 40 kh); and (4) cold-working (10%). The results were as follows: (1) No significant SCC growth was observed on all types of cast stainless steels: aged (400degC x 40 kh) of SCS14A and SCS13A and 10% cold-working, in hydrogenated (low-potential) water at 320degC. (2) Aging at 400degC x 40 kh SCS14A (10%CW) markedly accelerated the SCC growth of cast material in high-potential water at 320degC, but no significant SCC growth was observed in the hydrogenated water, even after long-term thermal aging (400degC x 40 kh). (3) Thus, cast stainless steels have excellent SCC resistance in PWR primary water. (4) On the other hand, significant SCC growth was observed on all types of cast stainless steels: 10%CW SCS14A and SCS13A, in 8 ppm-oxygenated (high-potential) water at 320degC. (5) No large difference in SCC growth was observed between SCS14A (Mo) and SCS13A. (6) No

Mechanical properties and eddy current testing of thermally aged Z3CN20.09M cast duplex stainless steel

Science.gov (United States)

Liu, Tonghua; Wang, Wei; Qiang, Wenjiang; Shu, Guogang

2018-04-01

To study the thermal aging embrittlement of Z3CN20.09M duplex stainless steel produced in China, accelerated thermal aging experiments were carried out at 380 °C up to 9000 h. Microhardness measurements, Charpy impact and eddy current tests were performed on aged samples to characterize their thermal aging embrittlement. The results showed that the signal amplitude of eddy current decreased with the increase in aging time. Two quantitative correlations of the eddy current signal amplitude with both the Charpy impact energy, and the Vickers microhardness of the ferrite phase are obtained. The study showed that eddy current testing could be used to non-destructively evaluate the thermal aging embrittlement of cast duplex stainless steels.

33 CFR 162.20 - Flushing Bay near La Guardia Airport, Flushing, N.Y.; restricted area.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Flushing Bay near La Guardia Airport, Flushing, N.Y.; restricted area. 162.20 Section 162.20 Navigation and Navigable Waters COAST... NAVIGATION REGULATIONS § 162.20 Flushing Bay near La Guardia Airport, Flushing, N.Y.; restricted area. (a...

Theoretical study of [Li(H2O)n]+ and [K(H2O)n]+ (n = 1-4) complexes

International Nuclear Information System (INIS)

Wojcik, M.J.; Mains, G.J.; Devlin, J.P.

1995-01-01

The geometries, successive binding energies, vibrational frequencies, and infrared intensities are calculated for the [Li(H 2 O) n ] + and [K(H 2 O) n ] + (n = 1-4) complexes. The basis sets used are 6-31G * and LANL1DZ (Los Alamos ECP+DZ) at the SCF and MP2 levels. There is an agreement for calculated structures and frequencies between the MP2/6-31G * and MP2/LANL1DZ basis sets, which indicates that the latter can be used for calculations of water complexes with heavier ions. Our results are in a reasonable agreement with available experimental data and facilitate experimental study of these complexes. 19 refs., 4 figs., 6 tabs

n + 2759Co(En≤20 MeV) nuclear data calculation and analysis

International Nuclear Information System (INIS)

Wang Shunuan

2006-01-01

Whole set of nuclear data calculation in ENDF/B-6 format for n + 27 59 Co (E n ≤20 MeV) has been finished by using spherical optical model, coupled channel optical model, pre-equilibrium exciton model and Hauser-Fashbach equilibrium statistical model. The calculated cross sections, angular distributions, spectrum and double differential cross sections by using codes of APOM, ECIS95 and UNF are compared with all existing experimental data for n + 27 59 Co(E n ≤20 MeV) takefrom EXFOR. The calculated results are analyzed from point of view of theoretical model and model parameters used. The work is for CENDL-3. (authors)

46 CFR 56.25-20 - Bolting.

Science.gov (United States)

2010-10-01

..., Blanks, Flange Facings, Gaskets, and Bolting § 56.25-20 Bolting. (a) General. (1) Bolts, studs, nuts, and....01-2). (2) Bolts and studs must extend completely through the nuts. (3) See § 58.30-15(c) of this... steel stud bolts must be threaded full length or, if desired, may have reduced shanks of a diameter not...

10 years and 20,000 sources: the offsite source recovery project

Energy Technology Data Exchange (ETDEWEB)

Whitworth, Julia R [Los Alamos National Laboratory; Abeyta, Cristy L [Los Alamos National Laboratory; Pearson, Michael W [Los Alamos National Laboratory

2009-01-01

The Global Threat Reduction Initiative's (GTRI) Offsite Source Recovery Project (OSRP) has been recovering excess and unwanted sealed sources for ten years. In January 2009, GTRI announced that the project had recovered 20,000 sealed radioactive sources. This project grew out of early efforts at Los Alamos National Laboratory (LANL) to recover and disposition excess Plutonium-239 (Pu-239) sealed sources that were distributed in the 1960s and 1970s under the Atoms for Peace Program. Sealed source recovery was initially considered a waste management activity, as evidenced by its initial organization under the Department of Energy's (DOE's) Environmental Management (EM) program. After the terrorist attacks of 2001, however, the interagency community began to recognize the threat posed by excess and unwanted radiological material, particularly those that could not be disposed at the end of their useful life. After being transferred to the National Nuclear Security Administration (NNSA) to be part of GTRI, OSRP's mission was expanded to include not only material that would be classified as Greater-than-Class-C (GTCC) when it became waste, but also any other materials that might be a 'national security consideration.' This paper discusses OSRP's history, recovery operations, expansion to accept high-activity beta-gamma-emitting sealed sources and devices and foreign-possessed sources, and more recent efforts such as cooperative projects with the Council on Radiation Control Program Directors (CRCPD) and involvement in GTRI's Search and Secure project. Current challenges and future work will also be discussed.

Role of grain refinement in hardening of structural steels at preliminary thermomechanical treatment

International Nuclear Information System (INIS)

Bukhvalov, A.B.; Grigor'eva, E.V.; Davydova, L.S.; Degtyarev, M.V.; Levit, V.I.; Smirnova, N.A.; Smirnov, L.V.

1981-01-01

The hardening mechanism during preliminary thermomechanical treatment with deformation by cold rolling or hydroextrusion is studied on structural 37KhN3M1 and 38KhN3MFA steels. Specimens have been tested on static tension, impact strength and fracture toughness. It is shown that hydroextrusion application instead of rolling does not change the hardening effect of preliminary thermomechanical treatment (PTMT). It is established that the increase of preliminary deformation degree and the use of accelerated short term hardening heating provides a bett er grain refinement and the increase of PTMT hardening effect [ru

X-ray diffraction study of slags forming during corrosion resistant steel production

International Nuclear Information System (INIS)

Slavov, V.I.; Zadorozhnaya, V.N.; Shurygina, A.V.

1990-01-01

Using X-ray diffraction analysis slags, forming during corrosion-resistant 12Kh18N10T grade steel production by two flowsheets, are studied. Standard two-slag technology of steel production does not provide efficient disintegration of chromospinelides in slags, gives high steel contamination with respect to nonmetallic impurities, coarse structure and, as a consequence, presence of macrodefects on rolled products surface. One-slag steel melting technology with titanium alloying of the steel at vacuum causes fast removal of chromospinelides at the beginning of reduction period, promotes titanium absorption by the steel, refines nonmetallic inclusions, provides more fine structure and steel plasticity, removes surface defects

S-N Curves of high resistance steels in the gigacyclic regime; Curvas S-N de aceros de alta resistencia dentro del regimen gigaciclico

Energy Technology Data Exchange (ETDEWEB)

Marinez G, I [Conservatoire National des Arts et Metiers-Institut des Technologies et des Materiaux Avances (CNAM-ITMA), Paris (France); Dominguez A, G [Instituto Tecnologico de Celaya, Guanajuato (Mexico); Bathias, C [Conservatoire National des Arts et Metiers-Institut des Technologies et des Materiaux Avances (CNAM-ITMA), Paris (France)

2004-04-15

In this paper, the fatigue behavior of high strength steel used for mechanical parts has been investigated in the gigacycle fatigue regime. An experimental study has been carried out with both: R = 0.1 (perlitic-ferritic steel) and R = -1 (perlitic-ferritic steel, bainitic steel, martensitic steels) loads, at a high frequency of 20 khz up to 1010 cycles, to determine the S-N curves when fatigue life is more than 107 cycles. Comparison of experimental results at frequencies of 20 khz and 30 Hz with R = -1, shows that the S-N curve has a good agreement between 105 and 107 cycles for the high strength steels, Furthermore, fracture surface observations are made by SEM; the transition of crack initiation site is described. The generalization of gigacycle fatigue behavior is analyzed. More often initiation of fatigue crack at 109 cycles is a bulk phenomenon with an important effect of stress concentration due to mineral inclusions or perlitic platelets. Thus, the Murakami model is efficient when we can measure the defects associated with fracture, but it can not take into account the microstructure effect related to platelets phenomenon. [Spanish] En este trabajo se investigo el comportamiento en fatiga gigaciclica de varios aceros de alta resistencia utilizados en la industria automotriz. El estudio experimental se llevo a cabo utilizando dos diferentes valores de carga: R = 0.1 (acero perlitoferritico) y R = -1 (acero perlito-ferritico, acero bainitico, aceros martensiticos), a una frecuencia de ensayo de 20 kHz y hasta 1010 ciclos, para determinar las curvas S-N arriba de 107 ciclos. La comparacion de resultados experimentales obtenidos utilizando frecuencias de ensayo de 20 kHz y 30 Hz con la relacion de carga R = - 1, muestran la continuidad de las curvas S-N entre 105 y 107 ciclos para estos aceros de alta resistencia. Por otro lado, observaciones de la superficie de fractura se efectuaron utilizando el microscopio electronico de barrido; se describe la transicion

Comparison of the Infiniti vision and the series 20,000 Legacy systems.

Science.gov (United States)

Fernández de Castro, Luis E; Solomon, Kerry D; Hu, Daniel J; Vroman, David T; Sandoval, Helga P

2008-01-01

To compare the efficiency of the Infiniti vision system and the Series 20,000 Legacy system phacoemulsification units during routine cataract extraction. Thirty-nine eyes of 39 patients were randomized to have their cataract removed using either the Infiniti or the Legacy system, both using the Neosonix handpiece. System settings were standardized. Ultrasound time, amount of balanced salt solution (BSS) used intraoperatively, and postoperative visual acuity at postoperative days 1, 7 and 30 were evaluated. Preoperatively, best corrected visual acuity was significantly worse in the Infiniti group compared to the Legacy group (0.38 +/- 0.23 and 0.21 +/- 0.16, respectively; p = 0.012). The mean phacoemulsification time was 39.6 +/- 22.9 s (range 6.0-102.0) for the Legacy group and 18.3 +/-19.1 s (range 1.0-80.0) for the Infiniti group (p = 0.001). The mean amounts of intraoperative BSS used were 117 +/- 37.7 ml (range 70-195) in the Legacy group and 85.3 +/- 38.9 ml (range 40-200) in the Infiniti group (p = 0.005). No differences in postoperative visual acuity were found. The ability to use higher flow rates and vacuum settings with the Infiniti vision system allowed for cataract removal with less phacoemulsification time than when using the Legacy system. Copyright 2008 S. Karger AG, Basel.

26 CFR 20.2014-2 - “First limitation”.

Science.gov (United States)

2010-04-01

... United States and Country Y. The laws of Country Y provide for inheritance taxes computed as follows: Inheritance tax of surviving spouse: Value of stock $20,000 Value of bonds 50,000 Total value 70,000 Tax (16 percent rate) 11,200 Inheritance tax of son: Value of stock 60,000 Value of bonds $30,000 Total value 90...

The effect of laser treatment on the wear resistance of steel in corrosive media

International Nuclear Information System (INIS)

Plyatsko, G.V.; Porter, A.I.; Prejs, G.A.; Mojsa, M.I.

1975-01-01

The corrosion mechanical wearing properties of steel 45 treated with a laser beam (H 100 =7800 Mn/sq.m) under friction with nitrated steel 40KhNMA (HV=7000 Mn/sq.m), chrome cast iron Kh15M (hardened and low-temperature tempered, modified), perlite cast iron and bronze are studied. The aqueous buffers with pH=6 and 11 are used as a corrosion active media. In a weakly acid medium the most intensive wearing of steel 40KhNMA is observed at P=8 Mn/sq.m. Its wearing reduces due to increase of pressure to 12 Mn/sq.m. Extent of steel 45 wearing increases with pressure increase from 8 to 12 Mn/sg.m. Friction coefficient of this pair changes by jumps at an increase of normal pressure and its variation range is smaller than that observed in an alkaline medium. The maximum value of friction coefficient is shifted to the higher pressure. The wearing of cast iron Kh15M-steel 45 pair has an alternative pattern. In an alkaline medium the cast iron wearing intensity shows a linear increase with the normal contact pressure but that of the steel changes jumpwise attaining extreme at 8 and 12 Mn/sq.m. In a weak acid medium the intensity of grasping and graphitization at the friction surface of cast iron Kh15M-steel 45 pair is higher than that in the alkaline medium. Experiments demonstrate an effectiveness of the laser beam treatment of steel 45 for its friction in the alkaline medium with nitrated steel 40KhNMA and with hardened low-temperature tempered cast iron 45 under friction contact pressure as high as 8 Mn/sq.m, and in acid medium at 12 and 8 Mn/sq.m respectively. The laser treatment provides high corrosion-mechanical stability of steel 45 and the counterbodies described, as well as the low friction coefficient of these pairs

Web 2.0, Library 2.0, and Librarian 2.0:Preparing for the 2.0 World

Science.gov (United States)

Abram, S.

2007-10-01

There is a global conversation going on right now about the next generation of the web. It's happening under the name of Web 2.0. It's the McLuhanesque hot web where true human interaction takes precedence over merely `cool' information delivery and e-mail. It's about putting information into the real context of our users' lives, research, work and play. Concurrently, a group of information professionals are having a conversation about the vision for what Library 2.0 will look like in this Web 2.0 ecosystem. Some are even going so far as to talk about Web 3.0! Web 2.0 is coming fast and it's BIG! What are the skills and competencies that Librarian 2.0 will need? Come and hear an overview of Web 2.0 and a draft vision for Library 2.0 and an opinion about what adaptations we'll need to make to thrive in this future scenario. Let's talk about the Librarian 2.0 in our users' future!

Welding wires for high-tensile steels

International Nuclear Information System (INIS)

Laz'ko, V.E.; Starova, L.L.; Koval'chuk, V.G.; Maksimovich, T.L.; Labzina, I.E.; Yadrov, V.M.

1993-01-01

Strength of welded joints in arc welding of high-tensile steels of mean and high thickness by welding wires is equal to approximately 1300 MPa in thermohardened state and approximately 600 MPa without heat treatment. Sv-15Kh2NMTsRA-VI (EhK44-VI) -Sv-30Kh2NMTsRA-VI (EkK47-VI) welding wires are suggested for welding of medium-carbon alloyed steels. These wires provide monotonous growth of ultimate strength of weld metal in 1250-1900 MPa range with increase of C content in heat-treated state

Joint formation of dissimilar steels in pressure welding with superposition of ultrasonic oscillations

Energy Technology Data Exchange (ETDEWEB)

Surovtsev, A P; Golovanenko, S A; Sukhanov, V E; Kazantsev, V F

1983-12-01

Investigation results of kinetics and quality of carbon steel joints with the steel 12Kh18N10T, obtained by pressure welding with superposition of ultrasonic oscillations with the frequency 16.5-18.0 kHz are given. The effect of ultrasonic oscillations on the process of physical contact development of the surfaces welded, formation of microstructure and impact viscosity of the compound, is shown.

Spin resolved electronic transport through N@C20 fullerene molecule between Au electrodes: A first principles study

Science.gov (United States)

Caliskan, Serkan

2018-05-01

Using first principles study, through Density Functional Theory combined with Non Equilibrium Green's Function Formalism, electronic properties of endohedral N@C20 fullerene molecule joining Au electrodes (Au-N@C20) was addressed in the presence of spin property. The electronic transport behavior across the Au-N@C20 molecular junction was investigated by spin resolved transmission, density of states, molecular orbitals, differential conductance and current-voltage (I-V) characteristics. Spin asymmetric variation was clearly observed in the results due to single N atom encapsulated in the C20 fullerene cage, where the N atom played an essential role in the electronic behavior of Au-N@C20. This N@C20 based molecular bridge, exhibiting a spin dependent I-V variation, revealed a metallic behavior within the bias range from -1 V to 1 V. The induced magnetic moment, spin polarization and other relevant quantities associated with the spin resolved transport were elucidated.

Museografía web 2.0 en Aragón

OpenAIRE

Rivero Gracia, María Pilar

2011-01-01

Se analiza la utilización de Internet por parte de los museos aragoneses prestando especial atención a las nuevas tendencias derivadas de la implantación de aplicaciones de la Web 2.0 y a la innovación derivada de los proyectos de investigación en curso en el campo de la cibermuseología.Además, se proporcionan referencias a los portales generales de acceso, catálogos on line y visitas virtuales más destacadas.

Ab initio density functional theory study of non-polar (10-10), (11-20) and semipolar {20-21} GaN surfaces

Czech Academy of Sciences Publication Activity Database

Mutombo, Pingo; Romanyuk, Olexandr

2014-01-01

Roč. 115, č. 20 (2014), "203508-1"-"203508-5" ISSN 0021-8979 Grant - others:AVČR(CZ) M100101201 Institutional support: RVO:68378271 Keywords : non-polar GaN * semipolar GaN * surface reconstructions * DFT Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 2.183, year: 2014

Kemi 2.0

DEFF Research Database (Denmark)

Johannesson, Anne Boie

2014-01-01

temaer, hvor eleverne laver deres eget didaktiske design indenfor rammerne af lærerens didaktiske design. Fokus i gruppearbejdet er udarbejdelse af web 2.0-produkter og meningsforhandling. Lærerens rolle er at hjælpe når der er behov for det, fremfor at lave almindelig tavleundervisning. Kemi 2.0 ligger......I dette projekt undersøges det hvordan kemi C på stx kan gøres it-baseret og almendannende. Løsningen er elevaktiverende og temabaseret undervisning samt fokus på kompetencer, fremfor kun på kvalifikationer. Det didaktiske design af kemi 2.0 er baseret på socialkonstruktivismen og inspireret af...... Dewey, Kolb, Illeris, Wenger og Luhmann. De unge karakteriseres med udgangspunkt i forskellige generationsbeskrivelser, og principper for didaktik 2.0, der imødekommer de unges forventninger og måder at lære på, skitseres. Principperne i kemi 2.0 er længerevarende gruppearbejde indenfor vedkommende...

A prominent figure in tatar dryhaeology. A. Kh. Khalikov’S 85th birthday anniversary

Directory of Open Access Journals (Sweden)

Khuzin Fayaz Sh.

2014-06-01

Full Text Available The article is devoted to scientific activity of Alfred Khasanovich Khalikov (May 30, 1929–July 24, 1994, an outstanding scholar, Dr. habil. (History, Professor, corresponding member of the Academy of Sciences of Tatarstan, a renowned specialist in archaeology and ancient history of the Turkic and Finno-Ugric peoples of the Volga-Ural region. A.Kh. Khalikov was a pioneer discoverer of hundreds of monuments referring to different archaeological periods, from the Paleolithic to modern times. However, the principal sphere of his scientific interests was medieval archaeology and history of the Volga region peoples. As head of major archaeological expeditions, such as the Mari, Tatar, Bilyar, “The Kazan Kremlin”, etc. ones, A.Kh. Khalikov had emerged as organizer of large-scale research in the territory of Tatarstan and other republics and regions of the Middle Volga region for 40 years,. A.Kh. Khalikov created an extensive cultural-chronological scheme of the Stone, the Chalcolithic, the Bronze and Early Iron ages in the Volga region, offered his own concept of ethnogenesis of the Finno-Ugric and Turkic peoples of the region. A.Kh. Khalikov authored over 400 articles and 20 books covering the origin and early history of the peoples of the Middle Volga and Ural regions. On his initiative, a complete list of archaeological monuments of Tatarstan in 6 volumes was created. Preservation of monuments of history and culture was an important direction of his activities. Professor A.Kh. Khalikov was engaged in fruitful teaching process at Kazan State University and created his own scientific school.

Specific features of the occurrence, development, and re-compaction of spall and shear fractures in spherically-convergent shells made of unalloyed iron and some steels under their spherical explosive loading

International Nuclear Information System (INIS)

Kozlov, E.A.; Brichikov, S.A.; Gorbachev, D.M.; Brodova, I.G.; Yablonskikh, T.I.

2007-01-01

Results of comparative metallographic examination of recovered shells exposed to explosive loading in two modes (with and without a heavy casing confining explosion products scatter) are presented. The shells were made of high-purity and technical-grade unalloyed iron with the initial grain size 250 and 125 μm, steel 30KhGSA in delivery state and quenched up to HR C 35...40, austenitic stainless steel 12Kh18N10T. The heavy casing used in experiments is demonstrated to ensure a rather compact convergence of shells destroyed at high radii. In the described comparative experiments, one managed to compile the 12Kh18N10T steel shell, after it was spalled at high radii and exposed to shear fracture and spallation layer fragmentation at medium radii, into a compact sphere but failed to do the same with the 30KhGSA quenched steel shell after it was fractured according to spall and shear mechanisms at high and medium radii. Polar zones of this steel shell have obvious undercompressed areas due to significant dissipative losses to overcome the shear strength. Occurrence, development, and re-compaction of spall and shear fractures in spherically-convergent shells made of materials, which were already carefully investigated in 1D- and 2D-geometry experiments, were systematically studied in order to verify and validate new physical models of dynamic fractures, as well as up-to-date used in 1D-, 2D- and 3D-numerical algorithms [ru

Special Features of Induction Annealing of Friction Stir Welded Joints of Medium-Alloy Steels

Science.gov (United States)

Priymak, E. Yu.; Stepanchukova, A. V.; Bashirova, E. V.; Fot, A. P.; Firsova, N. V.

2018-01-01

Welded joints of medium-alloy steels XJY750 and 40KhN2MA are studied in the initial condition and after different variants of annealing. Special features of the phase transformations occurring in the welded steels are determined. Optimum modes of annealing are recommended for the studied welded joints of drill pipes, which provide a high level of mechanical properties including the case of impact loading.

Stainless Steel 2.0-mm Locking Compression Plate Osteosynthesis System for the Fixation of Comminuted Hand Fractures in Asian Adults

Directory of Open Access Journals (Sweden)

Hing-Cheong Wong

2011-12-01

Conclusions: The stainless steel 2.0-mm LCP is useful for the fixation of unstable comminuted hand fractures, especially in metacarpal bones, because of its advantage of better stability, which allows more aggressive rehabilitation. However, its design is not very versatile and, therefore, limits its use in the finger region. Its bulkiness frequently causes implant impingement. The patients must be informed about the chance of implant removal later.

Corrosion resistance of heat exchange equipment in hydrotreating Orenburg Condensate

International Nuclear Information System (INIS)

Teslya, B.M.; Burlov, V.V.; Parputs, I.V.; Parputs, T.P.

1986-01-01

The authors study the corrosion resistance of materials of construction and select appropriate materials for the fabrication of heat exchange equipment that will be serviceable under hydrotreating conditions. This paper discusses the Orenburg condensate hydrotreating unit which has been shut down repeatedly for repair because of corrosion damage to components of heat exchangers in the reactor section: tube bundles (08Kh18N10T steel), corrugated compensators (12Kh18N10T steel), and pins of the floating heads (37Kh13N8G8MFB steel). The authors recommend that the tube bundles and the compensators in heat exchangers in the reaction section should be fabricated of 08Kh21N6M2T or 10Kh17N13M2T steel. The pins have been replaced by new pins made of 10Kh17N13 X M2T steel, increasing the service life from 6-12 months to 2 years

Impact Strength of Austenitic and Ferritic-Austenitic Cr-Ni Stainless Cast Steel in -40 and +20°C Temperature

Directory of Open Access Journals (Sweden)

Kalandyk B.

2014-10-01

Full Text Available Studies described in this paper relate to common grades of cast corrosion resistant Cr-Ni steel with different matrix. The test materials were subjected to heat treatment, which consisted in the solution annealing at 1060°C followed by cooling in water. The conducted investigations, besides the microstructural characteristics of selected cast steel grades, included the evaluation of hardness, toughness (at a temperature of -40 and +20oC and type of fracture obtained after breaking the specimens on a Charpy impact testing machine. Based on the results of the measured volume fraction of ferrite, it has been found that the content of this phase in cast austenitic steel is 1.9%, while in the two-phase ferritic-austenitic grades it ranges from 50 to 58%. It has been demonstrated that within the scope of conducted studies, the cast steel of an austenitic structure is characterised by higher impact strength than the two-phase ferritic-austenitic (F-A grade. The changing appearance of the fractures of the specimens reflected the impact strength values obtained in the tested materials. Fractures of the cast austenitic Cr-Ni steel obtained in these studies were of a ductile character, while fractures of the cast ferritic-austenitic grade were mostly of a mixed character with the predominance of brittle phase and well visible cleavage planes.

Web 2.0 y herramientas en red para Educación Infantil y Primaria

OpenAIRE

Solano Fernández, Isabel Mª

2010-01-01

Documento sobre Web 2.0 y herramientas y recursos para Eduación Infantil y Primaria, en el que se hace un recorrido por los términos Web 1.0, Web 2.0 y Web 3.0, y se presentan diversos recursos a partir de diferentes categorías: en función de las variables espacio-temporales, del sistema simbólico y la función. Ejercicios prácticos

10 years and 20,000 sources: the GTRI offsite source recovery project

International Nuclear Information System (INIS)

Whitworth, Julia; Streeper, Charles; Cuthbertson, Abigail

2009-01-01

Full text: The Global Threat Reduction Initiative's (GTRI) Offsite Source Recovery Project (OSRP) has been recovering excess and unwanted radioactive sealed sources for ten years. In January 2009, GTRI announced that the project had recovered 20,000 sealed radioactive sources. This project grew out of early efforts at Los Alamos National Laboratory (LANL) to recover and disposition excess Plutonium-239 ( 239 Pu) sealed sources that were distributed in the 1960s and 1970s under the Atoms for Peace Program. Decades later, these sources began to exceed their design life or fall out of regular use. Sealed source recovery was initially considered a waste management activity, but after the terrorist attacks of 2001, the interagency community began to recognize the threat posed by excess and unwanted radiological materials, particularly those that could not be disposed at the end of their useful life. After being transferred to the U.S. National Nuclear Security Administration (NNSA) to be part of GTRI, OSRP's mission was expanded to include not only material that would be classified as Greater-than-Class-C (GTCC) when it became waste, but also any other materials that might constitute a 'national security consideration'. This paper discusses OSRP's history, recovery operations, expansion to accept high-activity beta-gamma-emitting sealed sources and devices and foreign-possessed sources, and more recent efforts such as involvement in GTRI's Search and Secure project. Current challenges and future work will also be discussed

Aplicaciones y estrategias "Web 2.0" en la Educación Médica

Directory of Open Access Journals (Sweden)

Reynaldo Badillo Abril

2011-01-01

Full Text Available Por su alta interactividad, la Web 2.0 promueve una mayor participación del usuario en el manejo de los contenidos, lo cual lleva a nuevos usos de colaboración en Internet; perspectiva que podría transformar significativamente las prácticas educativas. Los elementos dominantes del Web 2.0 incluyen: Blogs, wikis, editores de textos en la Web; agregadores RSS, marcadores sociales, podcasts, sitios en la red para compartirdocumentos, fotografías, presentaciones, microblogging, etc. La comunidad educativa necesita estar enterada de estas tecnologías y de su papel potencial en los procesos de aprendizaje/enseñanza en el campo de la medicina. Con este artículo revisamos las herramientas más comunes de la Web 2.0, las experiencias sobre su uso en la educación médica y algunas recomendaciones para utilizarlas en ambientes educativos virtuales.

Optimum conditions for aging of stainless maraging steels

International Nuclear Information System (INIS)

Mironenko, P.A.; Krasnikova, S.I.; Drobot, A.V.

1980-01-01

Aging kinetics of two 0Kh11N10M2T type steels in which 3 % Mo (steel 1), and 3 % Mo and 11 % Co (steel 2) had been additionally introduced instead of titanium were investigated. Electron microscopy and X-ray methods were used. It was ascertained that the process of steel aging proceeded in 3 stages. Steel 2 was hardened more intensively during the aging, had a higher degree of hardness and strength after the aging, weakened more slowly if overaged than steel 1. The intermetallide hcp-phase Fe 2 Mo was the hardening phase on steels extended aging. Optimum combination of impact strength and strength was was achieved using two-stage aging: the first stage - maximum strength aging was achieved, the second stage - aging at minimum temperatures of two-phase α+γ region

Instalación solar fotovoltaica -20 Kw para conexión a red

OpenAIRE

Sacristán Benito, Silvia

2014-01-01

Este TFG trata sobre el diseño de una instalación de generación eléctrica de una potencia nominal de 20 kW mediante paneles fotovoltaicos. Estos paneles se situarán sobre la cubierta de una nave industrial en la localidad de Soria. Toda la energía producida será vertida a la red eléctrica de baja tensión, abasteciendo al entorno cercano. Se describe, el funcionamiento de una instalación de este tipo, en la cual el componente más destacado es el panel fotovoltaico, que genera...

Wear Resistance of Steel 20MnCr5 After Surfacing with Micro-jet Cooling

Directory of Open Access Journals (Sweden)

Tarasiuk W.

2016-09-01

Full Text Available This paper presents results of experimental research concerning the impact of an innovative method of micro-jet cooling on the padding weld performed with MIG welding. Micro-jet cooling is a novel method patented in 2011. It enables to steer the parameters of weld cooling in a precise manner. In addition, various elements which may e.g. enhance hardness or alter tribological properties can be entered into its top surface, depending on the applied cooling gas. The material under study was steel 20MnCr5, which was subject to the welding process with micro-jet cooling and without cooling. Nitrogen was used as a cooling gas. The main parameter of weld assessment was wear intensity. The tests were conducted in a tribological pin-on-disc type position. The following results exhibit growth at approximately 5% in wear resistance of padding welds with micro-jet cooling.

Residual stress determination by neutron diffraction in a car gear-shaft made of 20NiCrMo2 alloyed case hardening steel

Czech Academy of Sciences Publication Activity Database

Rogante, M.; Mazzanti, M.; Mikula, Pavol; Vrána, Miroslav

2012-01-01

Roč. 50, č. 4 (2012), s. 213-220 ISSN 0023-432X R&D Projects: GA ČR(CZ) GAP204/12/1360 Institutional support: RVO:61389005 Keywords : 20NiCrMo2 steel * gear-shaft * caser hardening * residual stress * neutron diffraction Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 0.687, year: 2012

Single-particle properties of N = 12 to N = 20 silicon isotopes within the dispersive optical model

Science.gov (United States)

Bespalova, O. V.; Ermakova, T. A.; Klimochkina, A. A.; Spasskaya, T. I.

2017-09-01

Experimental neutron and proton single-particle energies in N = 12 to N = 20 silicon isotopes and data on neutron and proton scattering by nuclei of the isotope 28Si are analyzed on the basis of the dispersive optical model. Good agreement with available experimental data was attained. The occupation probabilities calculated for the single-particle states in question suggest a parallel-type filling of the 1 d and 2 s 1/2 neutron states in the isotopes 26,28,30,32,34Si. The single-particle spectra being considered are indicative of the closure of the Z = 14 proton subshell in the isotopes 30,32,34Si and the N = 20 neutron shell.

Mechanical and fracture properties at impact loading of selected steels for nuclear power engineering

International Nuclear Information System (INIS)

Buchar, J.; Bilek, Z.

1988-01-01

The possibilities are briefly characterized of experimental research of mechanical and fracture properties of steels used in nuclear power engineering. Attention is paid to plastic deformation and the assessment of fracture formation during impact loading. The results are reported for steels 15Kh2MFA and 10GN2MFA. For steel 15Kh2MFA the effect was also studied of neutron radiation at different temperatures. From the theory developed for non-irradiated material 10GN2MFA, a prediction is made within the original model of the fracture stress value for steel 15Kh2MFA in both non-irradiated and irradiated states. The conclusion is arrived at that the existing methods of assessing steel properties at impact load allow obtaining knowledge of all significant effects during actual stress, this using only small specimens of the materials. (Z.M.). 4 figs., 8 refs

Composition of the spheroidal objects in KhN77TYuR-VD alloy

International Nuclear Information System (INIS)

Kotkis, M.A.; Nabutovskii, L.S.; Ostrov, A.E.; Zil'berman, A.G.

1986-01-01

The authors make an element analysis of the spheroidal objects in KhN77TYuR-VD alloy with the use of the energy dispersion microanalyzer with which the Stereoscan S-180 scanning electron microscope is equipped. Examples of the qualitative element analysis are shown. The results of the investigations show that the composition of the spheroidal inclusions includes nickel, chromium, titanium, iron, and also silicon and sulfur. The information obtained makes it possible to make an assumption on the mechanism of origin of these objects

Unit rupture work as a criterion for quantitative estimation of hardenability in steel

International Nuclear Information System (INIS)

Kramarov, M.A.; Orlov, E.D.; Rybakov, A.B.

1980-01-01

Shown is possible utilization of high sensitivity of resistance to fracture of structural steel to the hardenability degree in the course of hardening to find the quantitative estimation of the latter one. Proposed is a criterion kappa, the ratio of the unit rupture work in the case of incomplete hardenability (asub(Tsub(ih))) under investigation, and the analoguc value obtained in the case of complete hardenability Asub(Tsub(Ch)) at the testing temperature corresponding to the critical temperature Tsub(100(M). Confirmed is high criterion sensitivity of the hardened steel structure on the basis of experimental investigation of the 40Kh, 38KhNM and 38KhNMFA steels after isothermal hold-up at different temperatures, corresponding to production of various products of austenite decomposition

Shape coexistence and mixing in N ∼ 20 region

International Nuclear Information System (INIS)

Utsuno, Yutaka; Otsuka, Takaharu; Mizusaki, Takahiro; Honma, Michio

2005-01-01

Spherical-deformed shape coexistence in the N ∼ 20 region is studied with the Monte Carlo shell model calculation. We focused upon the role of the configuration mixing in its description, and found that the deformed state is not correctly positioned until the mixing is treated in a proper way. It is also mentioned that the intruder component in 33 Al is accessible through the measurement of the magnetic moment

Industrial cost effective n-pasha solar cells with >20% efficiency

Energy Technology Data Exchange (ETDEWEB)

Romijn, I.G.; Van Aken, B.; Anker, J.; Barton, P.; Gutjahr, A.; Komatsu, Y.; Koppes, M.; Kossen, E.J.; Lamers, M.; Saynova, D.S.; Tool, C.J.J.; Zhang, Y. [ECN Solar Energy, P.O. Box 1, NL-1755 ZG Petten (Netherlands); Venema, P.R.; Vlooswijk, A.H.G. [Tempress Systems BV, Radeweg 31, 8171 MD Vaassen (Netherlands); Schmitt, C.; Kuehnlein, H.; Bay, N. [RENA GmbH, Hans-Bunte-Strasse 19, D-79108, Freiburg im Breisgau (Germany); Koenig, M.; Stassen, A.F. [Heraeus Precious Metals GmbH and Co. KG, Heraeusstrasse 12-14, D-63450, Hanau (Germany)

2013-10-15

The n-Pasha cell is a bifacial solar cell concept with average efficiencies between 19.8% and 20% and is optimized to enable high efficiencies with narrow distribution on wafers from the complete n-type ingots (2 to 10 {omega}-cm). This reduces the yield losses from a wafer point of view, which is important since the wafer costs make up the largest part ({approx}40%) of the total module costs for n-Pasha modules. The module fabrication itself adds up to {approx}35% of the module costs/Wp costs, which leaves {approx}25% of the costs/Wp for the cell production. We found that the costs/Wp for the 20% n-Pasha cell and module process are very similar to those of a 19% p-type cell, assuming similar wafer and module manufacturing costs. In the paper the successful implementation of a reduction of >60% in BBr{sub 3} consumption, and a reduction of >50% in Ag consumption are described, while keeping the n-Pasha cell efficiency at the same level. According to our calculations, the achieved reduction of the Ag and BBr{sub 3} consumption will lower the costs/Wp for n-Pasha modules below that of p-type. The majority of the efficiency losses in the n-Pasha cell are due to recombination in the diffused layers and below the contact regions. By tuning both the emitter and BSF profile, an efficiency gain of 0.4% absolute has been obtained. Based on the simulations and experimental results, the path towards further optimization and efficiencies approaching 21% is shown.

La biblioteca académica 2.0: Innovación en México

Directory of Open Access Journals (Sweden)

Lizbeth Berenice Herrera Delgado

2011-01-01

Full Text Available La Biblioteca 2.0 (B2 ha sido objeto de atención y difusión, de una discusión entre los medios electrónicos, cobijada por el marco informal de los bloggers bibliotecarios o “bibliobloggers2”. En el presente trabajo se cavila sobre la B2 y su innovación desde el entorno académico y su contexto en México. Ejercicio que pone de manifiesto por un lado el rol que juega en las tecnologías de la información y la comunicación (TIC, mientas que por el otro lado se cuestiona su papel al interior de las Unidades de Información. Conjugando entonces las propuestas que componen a la B2, estudiando los tipos de innovación que existen y vertiendo finalmente una opinión acorde al contexto mexicano es que surge así la concepción de las bibliotecas académicas mexicanas 2.0.

La biblioteca académica 2.0: Innovación en México

Directory of Open Access Journals (Sweden)

Lizbeth Berenice Herrera Delgado

2011-07-01

Full Text Available La Biblioteca 2.0 (B2 ha sido objeto de atención y difusión, de una discusión entre los medios electrónicos, cobijada por el marco informal de los bloggers bibliotecarios o “bibliobloggers1”. En el presente trabajo se cavila sobre la B2 y su innovación desde el entorno académico y su contexto en México. Ejercicio que pone de manifiesto por un lado el rol que juega en las tecnologías de la información y la comunicación (TIC, mientas que por el otro lado se cuestiona su papel al interior de las Unidades de Información. Conjugando entonces las propuestas que componen a la B2, estudiando los tipos de innovación que existen y vertiendo finalmente una opinión acorde al contexto mexicano es que surge así la concepción de las bibliotecas académicas mexicanas 2.0.

20 CFR 437.33 - Supplies.

Science.gov (United States)

2010-04-01

... supplies exceeding $5,000 in total aggregate fair market value upon termination or completion of the award... 20 Employees' Benefits 2 2010-04-01 2010-04-01 false Supplies. 437.33 Section 437.33 Employees... Supplies. (a) Title. Title to supplies acquired under a grant or subgrant will vest, upon acquisition, in...

Determination of residual stresses in steel 20 comparison of the results obtained by the Barkhausen noise and X-ray diffraction

International Nuclear Information System (INIS)

Fernandez, L. M.; Herrera, V.; Suarez, J.C.; Merino, F.J.

1997-01-01

During a heat treatment (quenching, surface hardening, Thermochemical treatment) the metallic alloys undergo temperature variations and phase transformation. The resulting changes give rise to internal stresses in the piece. Phase transformation modifies the thermomechanical behavior of the material through the change of mechanical properties ( hardness, fatigue-behaviour, corrosion resistance, electric resistivity, etc.) The aim of this paper is residual stress measurements in specimens of steel-20 submitted to different heat treatment, by two non destructive methods: Barkhausen and X-ray diffraction. Brakhausen Effects utilizes the magnetic properties of ferromagnetic materials such as ferritic and perlitic steels and provides a practical tool for surface streets evaluation. X-ray streets analysis is based on the measurement of lattice strains in different directions of specimen The results obtained by two techniques are compared, avowing a good agreement

Th{sup 232} (n,2n) Th{sup 231} cross section from threshold to 20.4 Mev

Energy Technology Data Exchange (ETDEWEB)

Butler, J P; Santry, D C

1961-07-01

The excitation curve for the reaction Th{sup 232} (n,2n) Th{sup 231} has been measured by the activation method from the threshold energy, 6.34 Mev, to 20.4 Mev, relative to the known cross section for the S{sup 32} (n, p) P{sup 32} reaction. Monoenergetic neutrons were obtained from the D (d,n) He{sup 3} and T (d,n) He{sup 4} reactions employing a Tandem Van de Graaff accelerator. From threshold to 9.0 Mev, the (n,2n) cross section rises rapidly, reaching its maximum value of 1.88 {+-} 0.09 barns in the region of 9.5 to 11.0 Mev. Above 11.5 Mev the (n,2n) cross section decreases due to competition of the (n,3n) and (n,2nf) reactions and at 20.4 Mev it has a value of 0.22{sub 5} {+-} 0.01{sub 5} barns. (author)

Porphyrins as Corrosion Inhibitors for N80 Steel in 3.5% NaCl Solution: Electrochemical, Quantum Chemical, QSAR and Monte Carlo Simulations Studies

Directory of Open Access Journals (Sweden)

Ambrish Singh

2015-08-01

Full Text Available The inhibition of the corrosion of N80 steel in 3.5 wt. % NaCl solution saturated with CO2 by four porphyrins, namely 5,10,15,20-tetrakis(4-hydroxyphenyl-21H,23H-porphyrin (HPTB, 5,10,15,20-tetra(4-pyridyl-21H,23H-porphyrin (T4PP, 4,4′,4″,4‴-(porphyrin-5,10,15,20-tetrayltetrakis(benzoic acid (THP and 5,10,15,20-tetraphenyl-21H,23H-porphyrin (TPP was studied using electrochemical impedance spectroscopy (EIS, potentiodynamic polarization, scanning electrochemical microscopy (SECM and scanning electron microscopy (SEM techniques. The results showed that the inhibition efficiency, η% increases with increasing concentration of the inhibitors. The EIS results revealed that the N80 steel surface with adsorbed porphyrins exhibited non-ideal capacitive behaviour with reduced charge transfer activity. Potentiodynamic polarization measurements indicated that the studied porphyrins acted as mixed type inhibitors. The SECM results confirmed the adsorption of the porphyrins on N80 steel thereby forming a relatively insulated surface. The SEM also confirmed the formation of protective films of the porphyrins on N80 steel surface thereby protecting the surface from direct acid attack. Quantum chemical calculations, quantitative structure activity relationship (QSAR were also carried out on the studied porphyrins and the results showed that the corrosion inhibition performances of the porphyrins could be related to their EHOMO, ELUMO, ω, and μ values. Monte Carlo simulation studies showed that THP has the highest adsorption energy, while T4PP has the least adsorption energy in agreement with the values of σ from quantum chemical calculations.

La web 2.0 en los sistemas de recuperación de información

Directory of Open Access Journals (Sweden)

Mary Eugenia Luna González

2012-04-01

Full Text Available Se realiza un análisis documental para obtener conocimiento sobre el avance de las nuevas tecnologías de la información y comunicación, y la explosión informativa y sobresaturación en la red consecuencia de tal avance, que solo es posible contrarrestar por medio de la utilización de sistemas de recuperación de información combinados con las ventajas ofrecidas en la web 2.0.

Industrial n-type solar cells with >20% cell efficiency

Energy Technology Data Exchange (ETDEWEB)

Romijn, I.G.; Anker, J.; Burgers, A.R.; Gutjahr, A.; Koppes, M.; Kossen, E.J.; Lamers, M.W.P.E.; Heurtault, Benoit; Saynova-Oosterling, D.S.; Tool, C.J.J. [ECN Solar Energy, Petten (Netherlands)

2013-03-15

To realize high efficiencies at low costs, ECN has developed the n-Pasha solar cell concept. The n-Pasha cell concept is a bifacial solar cell concept on n-Cz base material, with which average efficiencies of above 20% have been demonstrated. In this paper recent developments at ECN to improve the cost of ownership (lower Euro/Wp) of the n-Pasha cell concept are discussed. Two main drivers for the manufacturing costs of n-type solar cells are addressed: the n-type Cz silicon material and the silver consumption. We show that a large resistivity range between 2 and 8 cm can be tolerated for high cell efficiency, and that the costs due to the silver metallization can be significantly reduced while increasing the solar cell efficiency. Combining the improved efficiency and cost reduction makes the n-Pasha cell concept a very cost effective solution to manufacture high efficient solar cells and modules.

Fireside corrosion and steamside oxidation of 9-12% Cr martensitic steels exposed for long term testing

DEFF Research Database (Denmark)

Montgomery, Melanie; Jensen, S. A.; Rasmussen, F.

2009-01-01

MoV121 and HCM12 for the 12% Cr steels. The test tubes were welded in as part of the existing final superheaters in actual plants and exposure has been conducted over a ten year period (1994-2005). Compared to the older steel types, T92 and HCM12 utilise tungsten to improve their creep strength. From......To obtain long term corrosion and steam oxidation data for the 9-12%Cr ferritic steels, test tube sections have been exposed in Amager 3 and Avedore 1 coal fired power plants in Denmark (formerly run by ENERGI E2). Thus direct comparisons can be made for T91 and T92 for the 9% Cr steels and X20Cr...... Avedore I testing, T91 and T92 can be compared for exposure times up to similar to 48 000 h exposure. From Amager 3 testing, X20, HCM12 and T92 were tested; T92 has been exposed for up to 31 000 h and X20 and HCM12 have had 84 500 h exposure. Tube sections were removed for various exposure durations...

Evaluación de la tintura de guayaba 20 % en el tratamiento de las episiorrafias

Directory of Open Access Journals (Sweden)

Haydee Blanco Rodríguez

Full Text Available Introducción: la popularidad de las plantas medicinales y aromáticas se ha elevado considerablemente en los últimos años a través de su uso como hierbas medicinales. Objetivo: evaluar la tintura de guayaba al 20 % como antiséptico en la cura de las episiorrafias. Métodos: se realizó una investigación longitudinal, prospectiva, experimental, de casos y controles. El universo estuvo constituido por la totalidad de pacientes puérperas atendidas en el Hospital "27 de Noviembre", durante los años 2005-2010, N= 2 691. La muestra fue de n1= 300 casos tratados con la tintura de guayaba al 20 % y se comparó con un grupo control n2= 600 curado con alcohol yodado al 0,5 %. Para realizar el análisis estadístico se utilizó el método porcentual simple y el estadígrafo de chi cuadrado al 95 % de certeza. Resultados: las pacientes tratadas con la tintura de guayaba al 20 % evolucionaron satisfactoriamente en un 98,66 % y se infestaron solo el 1,34 %. Se infestó el 3,5 % de las pacientes curadas con el alcohol yodado al 0,5 %. El tiempo promedio de cicatrización con el uso de la tintura de guayaba al 20 % fue entre 8 y 9 días. Conclusiones: con el uso de la tintura de guayaba al 20 % existió un predominio de puérperas sin sepsis de la rafia, con un adecuado grado de cicatrización que superó significativamente a los resultados obtenidos con el alcohol yodado al 0,5 %.

The 2.0 Attitude: Politics beyond Blogs

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Roc Fages Ramió

2008-09-01

Full Text Available

La Actitud 2.0 es el elemento clave para aprovechar las posibilidades que el trabajo y la relación en red proporciona a empresas, organizaciones y administraciones. Si una persona es 2.0 quiere decir que utiliza las herramientas de la Web 2.0 para generar red y obtener beneficios personales o profesionales, individuales y colectivos, a partir de compartir conocimiento.

Este artículo empieza definiendo la Web 2.0 para demostrar que sin una actitud hacia este fenómeno el concepto no puede llegar a ningún sitio. A partir de esta conceptualización, el documento desarrolla la aplicación de la Actitud 2.0 a nivel de la política. Aquello que se conoce como Política 2.0, dice el texto, está aplicándose más desde el punto de vista de la ciudadanía que de los mismos políticos. Por lo tanto, la Política 2.0 crea una nueva forma de hacer política por parte de los ciudadanos. Eso quiere decir que éstos intentan generar una red de la que los políticos muchas veces no forman parte, incluso aunque se hayan integrado en el ámbito 2.0. El problema, pues, es que muchos políticos supuestamente 2.0 sólo utilizan las herramientas -blogs, Facebook, YouTube, Twitter...- sin entrar a fondo en las capacidades de la red. Porque, de hecho, la Política 2.0 les permitiría poder conocer, compartir y escuchar más directamente las necesidades y los intereses de la misma ciudadanía.

Llegados a este punto, y después de repasar algunas iniciativas interesantes de Política 2.0, el artículo acaba destacando la importancia de la nueva generación de nativos digitales, de personas que han nacido con el fenómeno 2.0 integrado, la generación de la Nintendo. Este grupo de jóvenes son los que tienen que marcar las tendencias que en un futuro muy inmediato serán realidades: trabajo y relación en red elevados al máximo exponente. Por lo tanto, les tiene que quedar claro a los políticos que, hoy por hoy, la Política 2.0 se

High temperature aging structures of Ni-20Cr-20W alloys

International Nuclear Information System (INIS)

Ohmura, Taizo; Sahira, Kensho; Sakonooka, Akihiko; Yonezawa, Noboru

1977-01-01

High temperature aging structures and age hardening of Ni-20Cr-20W alloys developed as the superalloys for the nuclear energy steelmaking, and effects of C and Zr additions to the alloys and the effect of preheat treatment on these properties were studied. M 6 C, α-W and two kinds of M 23 C 6 having different lattice parameters were found as precipitates in the alloys. M 23 C 6 whose lattice parameter was around 10.7A precipitated in the early stage of aging at 700 0 C-1,150 0 C, and the carbide changed to M 6 C at higher temperature than 1,000 0 C, but it remained as a stable carbide at lower temperature than 900 0 C. α-W precipitated at 800 0 C-1,100 0 C after precipitation of M 23 C 6 and it disappeared with increase of M 6 C. M 23 C 6 having the larger lattice parameter (10.9A) precipitated transitionally in aging stage of 26 x 10 3 in Larson Miller parameter at 900 0 C and 1,000 0 C. Age hardening corresponded to the precipitation of M 23 C 6 and it was reduced by the double pre-heat-treatment. Zr addition and amount of C influenced on the aging structure and age hardening. Zr seemed to be a favorable element to stabilize the carbide. (auth.)

Inhibition of salt precipitation, corrosion and corrosion fatigue of steel in neutral environments

International Nuclear Information System (INIS)

Mikhajlovskij, V.Ya.; Slobodyan, Z.V.; Soprunyuk, N.G.; Ivanov, A.M.

1983-01-01

Processes of salt precipitation, corrosion under dynamic and static conditions, are studied as well as corrosion fatigue of 20 and 40Kh steels in neutral aqueous media without and with the addition of compounds of several classes. The solution of calcium bicarbonate with the initial concentration [Ca(HCO 3 ) 2 ]=1.3 g/l and 3% NaCl solution in distilled water are used for investigation. The effectiveness index of salt precipitation inhibitor is determined by the change in the rate of calcium bicarbonate transformation into carbonate. The combination of results obtained permits to make the conclusion that tripolyphosphate and pyrophosphoric acid are rather perspective inhibitors of complex effect with low protective concentrations

Sinter ageing of equiatomic Al20Co20Cu20Zn20Ni20 high entropy alloy via mechanical alloying

International Nuclear Information System (INIS)

Mohanty, Sutanuka; Gurao, N.P.; Biswas, Krishanu

2014-01-01

The present investigation reports for the first time, the sinter ageing of equiatomic Al 20 Co 20 Cu 20 Ni 20 Zn 20 high entropy alloy (HEA), being synthesized by high energy ball milling of elemental powder blend under protective argon atmosphere, followed by consolidation of the milled powder by spark plasma sintering at different temperatures and applied pressure of 50 MPa. The detailed X-ray diffraction and transmission electron microscopy (TEM) studies indicate the presence of single phase, FCC β supersaturated solid solution in the ball milled powder. However, the sintering of the as-milled powder reveals the formation of α with ordered FCC (L1 2 ) structure within the grains of FCC γ. The microstructural analysis using TEM shows the precipitation of near cuboidal shaped α phase within the grains of γ. The size and shape of the precipitates depend on the sintering temperature. Hardness measurement of the sintered alloys suggests age hardening of the as-milled powder during sintering. The sinter age hardening of HEA is attributed to the fine scale precipitation of α phase. Detailed variation of the hardness and microstructural evolution are reported here to elucidate this novel finding

Analytical description of changes in the magnetic states of chromium-nickel steel under uniaxial elastic deformation

Science.gov (United States)

Gorkunov, E. S.; Yakushenko, E. I.; Zadvorkin, S. M.; Mushnikov, A. N.

2017-12-01

Dependences of magnetization and magnetic permeability of the 15KhN4D structural steel on the value of uniaxial stresses and magnetic field strength are obtained. A polynomial approximation fairly accurately describing the observed changes is proposed on the basis of experimental data.

Effect of operational conditions of electroerosion machining on the surface microgeometry parameters of steels and alloys

International Nuclear Information System (INIS)

Foteev, N.K.

1976-01-01

Studies the influence of pulse duration and a series of operating conditions of a ShGI-40-440 spark-machining generator on changes in the basic surface microgeometry characteristics of components of stainless steel 1Kh18N10T, steel St 45 and hard alloy T14K8. The microgeometry characteristics of spark-machined surfaces differ significantly from the corresponding characteristics of surfaces machined by cutting and vibro-rolling

Study of the closure of the nuclear shells N = 16, 20, 28 and 40

International Nuclear Information System (INIS)

Sorlin, O.

2005-12-01

There are 2 types of nuclear shell closures: one is associated to a number of the harmonic oscillator, typically N = 20 and 40, and the other is a consequence of the spin-orbital interaction that produces magic numbers such as N = 28, 50, 82 and N = 126. The first part of this work deals with the knowledge accumulated around the closure of the N = 28 shell. 3 means of investigation have been used: -) the study of beta decay nuclei (K 47 , Ar 46 , S 44 , Si 42 and Cl 45 ), -) the on-line spectroscopy of nuclei around N = 28, and -) the study of Ar 45 and Ar 47 through transfer reactions. The second part is dedicated to results concerning the nuclear structure of nuclei around N = 14-20 and around N = 40. (A.C.)

Study of TiC+TiN Multiple Films On Type of 316L Stainless Steel

Institute of Scientific and Technical Information of China (English)

XUE Qi; JIN Yong; HU Dong-ping; HUANG Ben-sheng; DENG Bai-quan

2004-01-01

In this paper, the synthesis process of TiC+TiN multiple films on super-low-carbon stainless steels is reported.The TiC layer is coated as the first layer in the multiple film, the change of growth rate of the film on the 316L Stainless steel is not same as the one on carbides substrates, while the mole ratio of CH4 to TiCl4 (mCH4/TiCl4) is changed from 1.2to 2.0. The Ti [C, N], as a kind of inter-layer between TiC and TiN layers, is helpful to improve the adhesion between the TiC and TiN layer. The cooling rate greatly influences the quality of the adhesion between the TiC+TiN film and substrates.

The 20-20-20 Package. Reform of Ets and scenarios cost analysis

International Nuclear Information System (INIS)

Clo, S.

2008-01-01

This article firstly analyses the important improvements that the European Commission indents to bring to the Ets, to its framework and functioning. The article intends to assess the impact of the 20-20-20 Package to the Italian industry, by analysing the different cost scenarios presented in the European Commission Impact Assessment. [it

Secondary recrystallisation in 20 w/o Cr-25 w/o Ni-Nb stabilised stainless steel

International Nuclear Information System (INIS)

Healey, T.; Brown, A.F.; Speight, M.V.

1976-11-01

The fuel cladding material for the Commercial Advanced Gas Reactor is a fine grain 20 w/o Cr-25 w/o Ni niobium stabilised stainless steel. The grain structure stability of this alloy has been investigated as a function of carbon content over the temperature range 930 - 990 0 C. It is demonstrated that the primary grain structure is susceptible to abnormal growth due to secondary recrystallisation of the initial fine grain structure after a composition and temperature dependent incubation period. The magnitude of the incubation period is analysed on the basis that secondary recrystallisation commences when randomly dispersed niobium carbide particles have coarsened to a critical size. The validity of the analysis is tested by comparing the predictions with experimental observation. The model is subsequently used to evaluate the incubation period for conditions of temperature, composition and microstructure which differ from those defined in the experimental studies. (author)

Influence of regenerative heat treatment on structure and properties of G20CrMo2 - 5 (L20HM cast steel

Directory of Open Access Journals (Sweden)

G. Golański

2008-03-01

Full Text Available Thc papcr prcscnts rcsuSts or rcscarch on thc influence of rcgcncratic hcat treatment on thc structurc and propcrtics [hardncss. impactcncrgy or L2O11M cnst stccl. Invcstipatcd material was taken from outer fmmc of a turbinc which was scrviccd for t 67 424 hours a! thctcmpcrauirc or 535 "C and prcssurc or 12.75 MPa. In psi-operating condition ~hicnv cstigntcd cast steel was cl~aracteri~cbdy low impactcncrpy of II I ant1 hart3ncss of 139HV30. Analysis uF the irlflue~~uuel ;lustcniriz;~ti on pariimctcrs (tcrnpcr;lturc and lime has rcvealcd rhntat thc tcinpcr;~turcr angc o f 895 + 955 "C (i-e. h3 - +I IO + 70 "C.fo r both 3 and 5 hours of holtl timc. rhc ohtaincd grain sizc amounls to 20+ 2511m. I has hccn pmved that tempcred bainitic-rcrri~ica nd remit ic-hainiric-pearlit ic stn~cturco f thc invcstigatcd cast stccl msurcs highimpact cncrgy, i.c. KV > 1001. as well a5 hardncss. i.e. 11Y30. just at thc tcrnpcmturc of OXl "C. 'I'crnpcmliirc or 7110 "C causcs i'~tnhcrincrclrsc of impact cncrgy along with a slight dccrcasc of hardncss. Morcovcr. it has hccn concludd that nppl ying oS under-annealinginstcad or tcmpcring. nflcr standardizalion. guarantees scquircd impact cncrgy of KY r 271.

Tribological Behavior of Plasma-Sprayed Al2O3-20 wt.%TiO2 Coating

Science.gov (United States)

Cui, Shiyu; Miao, Qiang; Liang, Wenping; Zhang, Zhigang; Xu, Yi; Ren, Beilei

2017-05-01

Al2O3-20 wt.% TiO2 ceramic coatings were deposited on the surface of Grade D steel by plasma spraying of commercially available powders. The phases and the microstructures of the coatings were investigated by x-ray diffraction and scanning electron microscopy, respectively. The Al2O3-20 wt.% TiO2 composite coating exhibited a typical inter-lamellar structure consisting of the γ-Al2O3 and the Al2TiO5 phases. The dry sliding wear behavior of the coating was examined at 20 °C using a ball-on-disk wear tester. The plasma-sprayed coating showed a low wear rate ( 4.5 × 10-6 mm3 N-1 m-1), which was matrix ( 283.3 × 10-6 mm3 N-1 m-1), under a load of 15 N. In addition, the tribological behavior of the plasma-sprayed coating was analyzed by examining the microstructure after the wear tests. It was found that delamination of the Al2TiO5 phase was the main cause of the wear during the sliding wear tests. A suitable model was used to simulate the wear mechanism of the coating.

Microstructure-based modelling of the long-term monotonic and cyclic creep of the martensitic steel X 20(22) CrMoV 12 1

International Nuclear Information System (INIS)

Henes, D.; Straub, S.; Blum, W.; Moehlig, H.; Granacher, J.; Berger, C.

1999-01-01

The current state of development of the composite model of deformation of the martensitic steel X 20(22) CrMoV 12 1 under conditions of creep is briefly described. The model is able to reproduce differences in monotonic creep strength of different melts with slightly different initial microstructures and to simulate cyclic creep with alternating phases of tension and compression. (orig.)

Analysis of the Effect of Cooling Intensity Under Volume-Surface Hardening on Formation of Hardened Structures in Steel 20GL

Science.gov (United States)

Evseev, D. G.; Savrukhin, A. V.; Neklyudov, A. N.

2018-01-01

Computer simulation of the kinetics of thermal processes and structural and phase transformations in the wall of a bogie side frame produced from steel 20GL is performed with allowance for the differences in the cooling intensity under volume-surface hardening. The simulation is based on the developed method employing the diagram of decomposition of austenite at different cooling rates. The data obtained are used to make conclusion on the effect of the cooling intensity on propagation of martensite structure over the wall section.

X-ray spectrum microanalysis of copper and stainless steel surface layer after electroerosion machining

International Nuclear Information System (INIS)

Abdukarimov, Eh.T.; Saidinov, S.Ya.

1989-01-01

The results of experimental investigations of the surface layer of copper and steel 12Kh18N10T after electroerrosion treatment by a rotating tungsten electrode in natural and distilled water are presented. It is established that the quantity of electrode material transferred to the surface of the steel treated grows with the spark discharge energy increase. Tungsten concentration in the surface layer reaches 5-10% with the average depth of penetration 40-50 μm

Effect of room temperature prestrain on creep life of austenitic 25Cr-20Ni stainless steels

International Nuclear Information System (INIS)

Park, In Duck; Ahn, Seok Hwan; Nam, Ki Woo

2004-01-01

25Cr-20Ni series strainless steels have an excellent high temperature strength, high oxidation and high corrosion resistance. However, further improvement can be expected of creep strength by work hardening prior creep. In the present study, the effect of prestraining at room temperature on the creep behavior of a Class M(STS310S) and a Class A(STS310J1TB) alloy containing precipitates have been examined. Prestraining was carried out at room temperature and range of prestrain was 0.5∼2.5 % at STS310J1TB and 2.0∼7.0 % at STS310S. Creep behavior and creep rate of pre-strained specimens were compared with that of virgin specimens. Room temperature prestraining produced the creep life that is longer than that of a virgin specimen both for STS310J1TB and STS310S when creep test was carried out at the temperature lower than recrystallization temperature. The reason for this improvement of creep life was ascribable to the interaction between dislocations and precipitates in addition to the dislocation-dislocation interaction in STS310J1TB and the dislocation-dislocation interaction in STS310S. The beneficial effect of prestraining in STS310J1TB was larger than that of STS310S

A luminary of tatar archaeology. To the 85th anniversary of the birth of A.Kh. Khalikov

Directory of Open Access Journals (Sweden)

Khuzin Fayaz Sh.

2014-06-01

Full Text Available The article is devoted to scientific activity of Alfred Khasanovich Khalikov (May 30, 1929–July 24, 1994, an outstanding scholar, Dr. habil. (History, Professor, corresponding member of the Academy of Sciences of Tatarstan, a renowned specialist in archaeology and ancient history of the Turkic and Finno-Ugric peoples of the Volga-Ural region. A.Kh. Khalikov was a pioneer discoverer of hundreds of monuments referring to different archaeological periods, from the Paleolithic to modern times. However, the principal sphere of his scientific interests was medieval archaeology and history of the Volga region peoples. As head of major archaeological expeditions, such as the Mari, Tatar, Bilyar, “The Kazan Kremlin”, etc. ones, A.Kh. Khalikov had emerged as organizer of large-scale research in the territory of Tatarstan and other republics and regions of the Middle Volga region for 40 years,. A.Kh. Khalikov created an extensive cultural-chronological scheme of the Stone, the Chalcolithic, the Bronze and Early Iron ages in the Volga region, offered his own concept of ethnogenesis of the Finno-Ugric and Turkic peoples of the region. A.Kh. Khalikov authored over 400 articles and 20 books covering the origin and early history of the peoples of the Middle Volga and Ural regions. On his initiative, a complete list of archaeological monuments of Tatarstan in 6 volumes was created. Preservation of monuments of history and culture was an important direction of his activities. Professor A.Kh. Khalikov was engaged in fruitful teaching process at Kazan State University and created his own scientific school.

Evidence for environmental conditions during the last 20 000 years in Southern Africa from C-13 in fossil hyrax dung

CSIR Research Space (South Africa)

Scott, L

2000-11-01

Full Text Available .elsevier.comrlocatergloplacha Evidence for environmental conditions during the last 20 000 years in Southern Africa from 13C in fossil hyrax dung L. Scott a,), J.C. Vogel b a Department of Botany and Genetics, Uni?ersity of the Orange Free State, PO Box 339, Bloemfontein 9300, South... in the studied hyrax middens, provide evidence that changes oc- curred on a regional scale. This is partly supported 13 by the d C sequences in stalagmite Talma and .Vogel, 1992 . In areas with summer-rains where AsweetB grass is likely to develop, d13C values...

Parameter optimization for steel quenching by C02-laser irradiation

International Nuclear Information System (INIS)

Moryashchev, S.F.; Kislitsyn, A.A.; Kosyrev, F.K.

1984-01-01

The dependence of average absorption factor on maximal temperature of the article surface during quenching by CO 2 -laser irradiation was determined empirically. The calculations of depth of a hardening zone and process productivity in 40 Kh, 4Kh13 steels and Armco-iron with regard to this dependence were conducted

Nitroreductase catalyzed biotransformation of CL-20

International Nuclear Information System (INIS)

Bhushan, Bharat; Halasz, Annamaria; Hawari, Jalal

2004-01-01

Previously, we reported that a salicylate 1-monooxygenase from Pseudomonas sp. ATCC 29352 biotransformed CL-20 (2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaaza-isowurtzitane) (C 6 H 6 N 12 O 12 ) and produced a key metabolite with mol. wt. 346Da corresponding to an empirical formula of C 6 H 6 N 10 O 8 which spontaneously decomposed in aqueous medium to produce N 2 O, NH4+, and HCOOH [Appl. Environ. Microbiol. (2004)]. In the present study, we found that nitroreductase from Escherichia coli catalyzed a one-electron transfer to CL-20 to form a radical anion (CL-20 - ) which upon initial N-denitration also produced metabolite C 6 H 6 N 10 O 8 . The latter was tentatively identified as 1,4,5,8-tetranitro-1,3a,4,4a,5,7a,8,8a-octahydro-diimidazo[4,5-b:4',5'-e] pyrazine [IUPAC] which decomposed spontaneously in water to produce glyoxal (OHCCHO) and formic acid (HCOOH). The rates of CL-20 biotransformation under anaerobic and aerobic conditions were 3.4+/-0.2 and 0.25+/-0.01nmolmin -1 mg of protein -1 , respectively. The product stoichiometry showed that each reacted CL-20 molecule produced about 1.8 nitrite ions, 3.3 molecules of nitrous oxide, 1.6 molecules of formic acid, 1.0 molecule of glyoxal, and 1.3 ammonium ions. Carbon and nitrogen products gave mass-balances of 60% and 81%, respectively. A comparative study between native-, deflavo-, and reconstituted-nitroreductase showed that FMN-site was possibly involved in the biotransformation of CL-20

Cold-rolled sheets production of stainless martensite-ageing steel smelted by vacuum arc and electroslag techniques

Energy Technology Data Exchange (ETDEWEB)

Rivkin, A A; Grishkov, A I; Suslin, A P; Nesterenko, A A; Lola, V N [Tsentral' nyj Nauchno-Issledovatel' skij Inst. Chernoj Metallurgii, Moscow (USSR)

1975-05-01

In cooperation with a number of metallurgical works the production of a high strength sheet stainless maraging steel EHP678 (000KH11N10M2T) has been tested by rolling cylindrical ingots of vacuum arc smelting at the blooming (the mass of rough ingots was 5.1 to 6.0 t, that of cleaned ingots - 3.8 to 5.1 t) or rectangular ingots of electroslag smelting (13 t) at the slabbing. The recommended regimes of heating and deformation are much similar to those used for the steel-KH18N10T. The output of valid cold-rolled sheets proved to be rather low (0.24 t/t for the vacuum arc smelting and 0.30 t/t for the electroslag smelting) mainly due to the losses on cleaning and a considerable portion of wrong-size slabs. The data are presented on the steel-EHP678 properties after various heat treatments. For the production of wide cold-rolled sheets of the steel EHP678 it is recommended to use steelmaking procedure with electroslag smelting including open-hearth melting in arc furnaces, rolling of ingots at the slabbing with heating up to 1260-1280 deg C (hold-up of 4.5 to 5 hrs); electroslag smelting for rectangular section slabs, rolling of ingots of electroslag smelting at the slabbing with their heating up to 1250 deg C (hold-up of 5.5 to 6 hrs), rolling at the 1680-type mill with heating up to 1250-1260 deg C (hold-up of 4 to 4.5 hrs ensuring the rolling temperature after a rough group not below 1100 deg C), quenching of hot-rolled sheets heating up to 920-940 deg C (hold-up of 3 to 3.5 min/mm), shot peening of sheets for descaling (provided the respective equipment is available) with a subsequent short-time pickling in an acid solution and cold rolling with a summary deformation of 35 to 45 %. The steelmaking with the electroslag smelting is much more profitable as regards to the fine technology of number of the main procedures, convenient cooperation of the works and a considerably greater output of the final products out of one ton of the steel produced.

Sàng khôn as A Theorizing Tool in Mobility Education

Directory of Open Access Journals (Sweden)

Ngoc Ba Doan

2017-02-01

Full Text Available The current virtual and physical mobility of humans, ideas, knowledge and epistemologies has major implications for education, especially in settings where English is seen as the default medium of instruction. While diversity is inherent in mobility, English-only pedagogy is a denial of the richness and potential of diverse resources learners bring with them through their mobility. This paper reports a philosophical stance and pedagogical practices employed by a lecturer in English language education at an Australian university. It argues that students’ full linguistic resources and epistemologies, known as sàng khôn, contribute to their agency and can be used as tools to theorise new knowledge in the context of their mobility education.

Experimental investigation on Performance and Emission Characteristics of J20, P20, N20 Biodiesel blends and Sound Characteristics of P20 Biodiesel blend Used in Single Cylinder Diesel Engine

Science.gov (United States)

rajasekar, R.; karthik, N.; Xavier, Goldwin

2017-05-01

Present work provides the effect of biodiesel blends and Sound Characteristics of P20 Biodiesel blend compared with Performance and emission Characteristics of diesel. Methods and analysis biodiesel blends was prepared by the Transesterification Process. Experiments were conducted in single cylinder constant speed direct injection diesel engine for various test fuels. Research is mainly focused on pongamia oil. It was observed that a 20% Pongamia oil blends and its properties were similar to diesel. The results showed that 20% Pongamia oil blends gave better performance, less in noise and emission compared with ester of Jatropha and neem oil blends. Hence Pongamia blends can be used in existing diesel engine without compromising the engine performance.

Effect of current intensity and pulse duration on polarization resistance of steel 20 in tap water measured on computer-aided unit

International Nuclear Information System (INIS)

Sorokin, V.I.; Boriskin, A.V.; Stepanets, G.P.; Shestopalova, A.O.

1995-01-01

The paper deals with a study of the impact of polarization current and time on the measurement of polarization resistance R p and coefficient K which relates it to the corrosion rate of low carbon Steel 20 in tap water. The formation of thick films of corrosion products on the surface of metal affects R p and K. The obtained data are used to develop an algorithm for corrosivity measuring microprocessor system operation program. 6 refs.; 3 figs.; 1 tab

n-3 fatty acids reduce plasma 20-hydroxyeicosatetraenoic acid and blood pressure in patients with chronic kidney disease.

Science.gov (United States)

Barden, Anne E; Burke, Valerie; Mas, Emilie; Beilin, Lawrence J; Puddey, Ian B; Watts, Gerald F; Irish, Ashley B; Mori, Trevor A

2015-09-01

Metabolism of arachidonic acid by cytochrome P450 ω-hydroxylase leads to the formation of 20-hydroxyeicosatetraenoic acid (20-HETE) that regulates vascular function, sodium homeostasis and blood pressure (BP). Supplementation with n-3 fatty acids is known to alter arachidonic acid metabolism and reduce the formation of the lipid peroxidation products F2-isoprostanes, but the effect of n-3 fatty acids on 20-HETE has not been studied. We previously reported a significant effect of n-3 fatty acids but not coenzyme Q10 (CoQ) to reduce BP in a double-blind, placebo-controlled intervention, wherein patients with chronic kidney disease (CKD) were randomized to n-3 fatty acids (4 g), CoQ (200 mg), both supplements or control (4 g olive oil), daily for 8 weeks. This study examined the effect of n-3 fatty acids on plasma and urinary 20-HETE in the same study, as well as plasma and urinary F2-isoprostanes, and relate these to changes in BP. Seventy-four patients completed the 8-week intervention. n-3 fatty acids but not CoQ significantly reduced plasma 20-HETE (P = 0.001) and F2-isoprostanes (P fatty acids. This is the first report that n-3 fatty acid supplementation reduces plasma 20-HETE in humans and that this associates with reduced BP. These results provide a plausible mechanism for the reduction in BP observed in patients with CKD following n-3 fatty acid supplementation.

Structure stability and magnetic properties of OsnB (n = 11–20 ...

Indian Academy of Sciences (India)

Recently, much attention has been paid to study the atomic clusters, especially the ... We designed. Figure 1. The lowest energy structures of OsnB (n = 11–20) clusters. ... then we calculated some relative properties of ground-state structure.

Non-destructive automated express method for determining the inclination of chromium-nickel steels IGC

International Nuclear Information System (INIS)

Nazarov, A.A.; Kamenev, Yu.B.; Kuusk, L.V.; Kormin, E.G.; Vasil'ev, A.N.; Sumbaeva, T.E.

1986-01-01

Methods of automated control of 18-10-type steel inclination to IGC are developed and a corresponding automated testing complex (ATS) is created. 08Kh18N10T steel samples had two variants of thermal treatment: 1) 1200 deg (5 h), 600 deg (50 h); 2) 1200 deg (5 h). Methods of non-destructive automated control of 18-10-type steel inclination to IGC are developed on the basis of potentiodynamic reactivation (PR) principle. Automated testing complex is developed, which has undergone experimental running and demonstrated a high confidence of results, reliability and easy operation

Nitrogen ion implantation effect on friction coefficient of tool steel

International Nuclear Information System (INIS)

Velichko, N.I.; Udovenko, V.F.; Markus, A.M.; Presnyakova, G.N.; Gamulya, G.D.

1988-01-01

Effect of nitrogen molecular ion implantation into KhVSG steel on the friction coefficient in the air and vacuum is investigated. Irradiation is carried out by the N 2 + beam with energy 120 keV and flux density 5 μ/cm 2 at room temperature in vacuum 5x10 -4 Pa. The integral dose of irradiation is 10 17 particle/cm 2 . Nitrogen ion implantation is shown to provide the formation of the modified layer changing friction properties of steel. The friction coefficient can either increase or decrease depending on implantation and test conditions. 4 refs.; 2 figs

Estimation of the Ultimate Tensile Strength of Steel from Its HB and HV Hardness Numbers and Coercive Force

Science.gov (United States)

Sandomirskii, S. G.

2017-11-01

A formula is derived to accurately describe the tabulated relation between the Brinell ( HB) and Vickers ( HV) hardnesses of steel over the entire range of their possible variation. This formula and the formulas describing the relation between the HB hardness of chromium-molybdenum and chromium-nickel steels and their ultimate tensile strength σu are used to analyze the change in σu of 38KhNM steel upon quenching and tempering. The data that reveal a relation between σu of 38KhNM steel and its coercive force are obtained.

KH 2PO4 as a novel catalyst for regioselective monobromination of aralkyl ketones using N-bromosuccinimide: a green methodology

Directory of Open Access Journals (Sweden)

P. Md. Khaja Mohinuddin

2015-08-01

Full Text Available A simple, regioselective and green method has been developed for the preparation of monobrominated ketones from various aralkyl ketones by using N-bromosuccinimide in presence of KH 2PO 4 in EtOH at reflux temperature. The present method is of short reaction time and simple with excellent isolated yields of products. The use of eco-friendly solvent, reuse of organic waste (succinimide and recyclable catalyst used for 4 times without loss of activity are advantageous. This is the first example of the use of KH 2PO 4 as a useful catalyst in organohalogen chemistry and the present method meets reduce-reuse-recycle (RRR principle towards development of green protocol.

Structural changes in complex steels with 12 % Cr during welding thermal cycle

International Nuclear Information System (INIS)

Ul'yanova, N.V.; Kurnosova, N.D.

1981-01-01

The structural changes in the heat affected zones of welded steam tubes of the 12Kh11V2MF and 18Kh12VMBFR steels, are investigated. A short-time heating of thin samples up to 1300-900 deg C with the aim of imitating the thermal welding cycle permits to determine temperatures of specific region formation in heat affeced zones of 12% Cr steels. The difference in the amounts and structure of σ-ferrite and γ-phase in these regions is established. A ''tongue'' nature of γ-phase grain growth is found in the temperature range of 1150-1100 deg C, while at 1300-1250 deg C σ-ferrite growth with the formation of saw-shape boundaries is observed. It is shown that tensile properties of imitated heat affected zone of 12Kh12VMBFP steel increase with heating temperature with the insignificant plasticity decrease. Impact strength on longitudinal samples decreases but remains higher than that determined by specifications [ru

Corrosion behaviour of high chromium ferritic stainless steels

International Nuclear Information System (INIS)

Kiesheyer, H.; Lennartz, G.; Brandis, H.

1976-01-01

Ferritic steels developed for seawater desalination and containing 20 to 28% chromium, up to 5% Mo and additions of nickel and copper have been tested with respect to their corrosion behaviour, in particular in chloride containing media. The materials in the sensibilized state were tested for intercrystalline corrosion susceptibility in the Strauss-, Streicher-, nitric acid hydrofluoric acid- and Huey-Tests. No intercrystalline corrosion was encountered in the case of the steels with 28% Cr and 2% Mo. The resistance to pitting was assessed on the basis of rupture potentials determined by potentiokinetic tests. The resistance of the steels with 20% Cr and 5% Mo or 28% Cr and 2% Mo is superior to that of the molybdenum containing austenitic types. Addition of nickel yields a significant increase in crevice corrosion resistance; the same applies to resistance in sulfuric acid. In boiling seawater all the materials tested are resistant to stress corrosion cracking. No sign of any type of corrosion was found on nickel containing steels after about 6,000 hours exposure to boiling 50% seawater brine even under salt deposits. (orig.) [de

Fatigue fracture of steel after mechanical and ultrasonic strengthening

International Nuclear Information System (INIS)

Stotskij, I.M.

1978-01-01

Fatigue fracture surfaces of samples after mechanical and ultrasonic strengthening have been studied metallographically and by electron fractography. Studied was the 40Kh steel hardened from 850 deg and then tempered at 180 deg or at 550 deg C. The ultrasound power was 25 kWt, the frequency was 20 kHz, the sample rotation velocity was 39.5 m/min. Mechanical and ultrasonic treatment was found to cause structural changes (formation of a white layer) and deformation of the material under the layer. The fatigue cracks were extending beyond the white layer; their propagation involved generation and coalescence of microcracks on account of segregation of carbides. It is concluded that mechanical and ultrasonic treatment should be used for increasing the fatigue strength of low and average strength materials rather than hardened or low-tempered ones

The radioprotective effect of a new aminothiol (20-PRA)

International Nuclear Information System (INIS)

Dolabela, M.F.; Lopes, M.T.P.; Pereira, M.T.; Steffani, G.M.; Pilo-Veloso, D.; Salas, C.E.; Nelson, D.L.

1998-01-01

We examined the radioprotective effect of aminothiol 2-N-propylamine-cyclohexane thiol (20-PRA) on a human leukemic cell line (K562) following various radiation doses (5,7.5 and 20 Gy) using a source of 60 Co γ-rays. At 5 Gy and 1nM 20-PRA, a substantial protective effect (58%) was seen 24 h after irradiation, followed by a decrease at 48 h (11%). At the high radiation dose (20 Gy) a low protective effect was also seen (35%). In addition, the anti tumorigenic potential of 10 nM 20-PRA was shown by the inhibition of crown gall formation induced by Agrobacterium tumefaciens. The radioprotective potency of 20-PRA is 10 5- 10 6 times higher than that of the aminothiol WR-1065 (N(2-mercaptoethyl)-1,3-diamino propane) whose protective effect is in the 0.1 to 1.0 nM range. (author)

Obtención y caracterización mecánica de un acero bainítico aleado con boro (10 y 20 ppm

Directory of Open Access Journals (Sweden)

M. A. Sierra

2012-01-01

Full Text Available Bainitic steels have become one of the metals most widely investigated in the last decade, due to the exceptional combination of mechanical properties. The advantage of such materials is to obtain free carbide structures that combine good mechanical strength with excellent toughness. In this work were established and properly controlled conditions to cast a bainitic steel with 10 and 20 ppm of boron, and subsequently thermomechanical treatment of rolling process between 1000 °C and 1200 °C. The microstructure characterization was carried out by optical microscopy and scanning electron microscopy, and mechanical characterization by hardness, strength-strain and toughness test at room temperature. The results show an ultimate strength of 1800 MPa and elongations of 16%. Also, it is noticeable increase in mechanical properties with increasing boron content in the steels. Probably boron acts as grain refiner and decrease the nucleation of the ferrite grain on austenite boundaries, improving the formation of Bainite.

Crustal Structure of Khövsgöl, Mongolia

Science.gov (United States)

Scott, A. M.; Meltzer, A.; Stachnik, J.; Russo, R.; Munkhuu, U.; Tsagaan, B.

2017-12-01

Mongolia is part of the Central Asian Orogenic Belt, an accretionary event that spanned 800 million years from the mid-Proterozoic to mid-Phanerozoic. As a result of the past collisional and rifting events, the modern Khövsgöl rift system of northern Mongolia contains a heterogeneous lithospheric structure. The current rift system has three parallel N-S trending basins that roughly align with terrane boundaries. Structures inherited during the accretionary events may be a factor influencing regional deformation. The forces that drive local deformation are not well understood, but varying processes have been proposed: far-field effects of India-Eurasian plate convergence, westward subduction of the Pacific plate, magmatic underplating at the base of the crust, mantle plume activity, and asthenospheric mantle convection. Determining the nature of crustal features within this poorly understood region may illuminate processes that control rifting within intracontinental settings. A network of 26 broadband seismic stations encompassing 200 square kilometers of the Khövsgöl rift system were deployed from August 2014 to June 2016. More than 2100 events were detected, and most earthquakes were concentrated near rift structures. Events between Busiin-Gol and Darkhad, the westernmost and central basins of the Khövsgöl rift system, are distributed within the crust. An active fault is outlined along the eastern border of the Darkhad basin. Khövsgöl earthquakes bound both sides of the rift. Along the northern border of Lake Khövsgöl, seismic events define a shallow active fault orthogonal to the basin. The largest event recorded within the network was a magnitude ml=5.2 located near the northeastern border of Lake Khövsgöl on 12-05-2014. The focal mechanism of this earthquake is predominantly strike-slip, but also includes an extensional component. This work focuses on earthquake relocation and calculating moment tensors and focal mechanisms of larger regional

Web 2.0 para la Biblioteca Digital de Nueva Generación (BDNG)

OpenAIRE

Barraza Difilippo, José Rafael

2010-01-01

El desarrollo del presente trabajo tiene como objetivo principal diseñar e implementar herramientas de la WEB 2.0 en el sistema BDNG (Biblioteca Digital de Nueva Generación) para mejorar la interacción del usuario con dicha plataforma, y así creando comunidades virtuales científicas interuniversitarias y redes de conocimiento que beneficiarán la producción científica del país.

Luminescence dynamics in AlGaN with AlN content of 20%

KAUST Repository

Soltani, Sonia; Bouzidi, Mouhamed; Touré , Alhousseynou; Gerhard, Marina; Halidou, Ibrahim; Chine, Zied; El Jani, Belgacem; Shakfa, Mohammad Khaled

2016-01-01

Optical properties and carrier dynamics of an AlGaN layer with an AlN content of 20% have been studied using time-resolved photoluminescence (TR-PL). Despite the high density of defects due to the relatively high AlN content, an intense PL emission from the sample has been detected. Low-temperature PL spectra exhibit several features, accompanied by a strong emission-wavelength dependence of the PL decay time. A significant red-shift of more than 200 meV from the band edge is recorded for the PL emission from localized states. Temperature-dependent PL spectra of the sample are dominated by the emission from localized states and, furthermore, show a relatively slight decrease by almost an order of magnitude with increasing temperature from 45 to 300 K. Our observations indicate strong, spatial localization effects of carriers, resulting in an increase in the radiative recombination rate.

Luminescence dynamics in AlGaN with AlN content of 20%

KAUST Repository

Soltani, Sonia

2016-12-15

Optical properties and carrier dynamics of an AlGaN layer with an AlN content of 20% have been studied using time-resolved photoluminescence (TR-PL). Despite the high density of defects due to the relatively high AlN content, an intense PL emission from the sample has been detected. Low-temperature PL spectra exhibit several features, accompanied by a strong emission-wavelength dependence of the PL decay time. A significant red-shift of more than 200 meV from the band edge is recorded for the PL emission from localized states. Temperature-dependent PL spectra of the sample are dominated by the emission from localized states and, furthermore, show a relatively slight decrease by almost an order of magnitude with increasing temperature from 45 to 300 K. Our observations indicate strong, spatial localization effects of carriers, resulting in an increase in the radiative recombination rate.

Heat treatment effect on ductility of nickel-base alloys

International Nuclear Information System (INIS)

Burnakov, K.K.; Khasin, G.A.; Danilov, V.F.; Oshchepkov, B.V.; Listkova, A.I.

1979-01-01

Causes of low ductility of the KhN75MBTYu and KhN78T alloys were studied along with the heat treatment effects. Samples were tested at 20, 900, 1100, 1200 deg C. Large amount of inclusions was found in intercrystalline fractures of the above low-ductile alloys. The inclusions of two types took place: (α-Al 2 O 3 , FeO(Cr 2 O 3 xAl 2 O 3 )) dendrite-like ones and large-size laminated SiO 2 , FeO,(CrFe) 2 O 3 inclusions situated as separate colonies. Heat treatment of the alloys does not increase high-temperature impact strength and steel ductility. The heating above 1000 deg C leads to a partial dissolution and coagulation of film inclusions which results in an impact strength increase at room temperature

20 CFR 606.20 - Cap on tax credit reduction.

Science.gov (United States)

2010-04-01

... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Cap on tax credit reduction. 606.20 Section 606.20 Employees' Benefits EMPLOYMENT AND TRAINING ADMINISTRATION, DEPARTMENT OF LABOR TAX CREDITS... Tax Credit Reduction § 606.20 Cap on tax credit reduction. (a) Applicability. Subsection (f) of...

The radioprotective effect of a new aminothiol (20-PRA

Directory of Open Access Journals (Sweden)

M.F. Dolabela

1998-08-01

Full Text Available We examined the radioprotective effect of aminothiol 2-N-propylamine-cyclo-hexanethiol (20-PRA on a human leukemic cell line (K562 following various radiation doses (5, 7.5 and 20 Gy using a source of 60Co g-rays. At 5 Gy and 1 nM 20-PRA, a substantial protective effect (58% was seen 24 h after irradiation, followed by a decrease at 48 h (11%. At the high radiation dose (20 Gy a low protective effect was also seen (35%. In addition, the antitumorigenic potential of 10 nM 20-PRA was shown by the inhibition of crown gall formation induced by Agrobacterium tumefaciens. The radioprotective potency of 20-PRA is 105-106 times higher than that of the aminothiol WR-1065 (N-(2-mercaptoethyl-1,3-diaminopropane whose protective effect is in the 0.1 to 1.0 mM range.

PENDIDIKAN KARAKTER MENURUT KH. WAHID HASYIM

Directory of Open Access Journals (Sweden)

Rangga Sa’adillah S. A. P.

2015-11-01

Full Text Available This library research examined two research questions. They are what thoughts of KH. Wahid Hasyim about the character education are and how the concept of character education by KH. Wahid Hasyim is relevant to the current condition of education in Indonesia. This study reveals two findings through an inductive analysis. The chief finding of this study is that there are eight characteristic values taught by KH.Wahid Hasyim including religious, tolerant, independent, democratic, patriotic, nasionalist, communicative, and keen on reading. Second, this study disclosed that the thought of character education by KH. Wahid Hasyim is in line with the goal of character education. He strove to build a multicultural national life, educate an intelligent civilization, build a noble character, encourage people to contribute to the development of human life, and develop the potential of having kind hearts, positive thoughts and good behavior as well as exemplary models. He also sought to generate enthusiasm of citizens to keep the peace, creativity, independence, and to be able to coexist with other nations in a harmony.

Thermal oxidation of reactively sputtered amorphous W80N20 films

International Nuclear Information System (INIS)

Vu, Q.T.; Pokela, P.J.; Garden, C.L.; Kolawa, E.; Raud, S.; Nicolet, M.

1990-01-01

The oxidation behavior of reactively sputtered amorphous tungsten nitride of composition W 80 N 20 was investigated in dry and wet oxidizing ambient in the temperature range of 450 degree C--575 degree C. A single WO 3 oxide phase is observed. The growth of the oxide follows a parabolic time dependence which is attributed to a process controlled by the diffusivity of the oxidant in the oxide. The oxidation process is thermally activated with an activation energy of 2.5±0.05 eV for dry ambient and 2.35±0.05 eV for wet ambient. The pre-exponential factor of the reaction constant for dry ambient is 1.1x10 21 A 2 /min; that for wet ambient is only about 10 times less and is equal to 1.3x10 20 A 2 /min

Effect of non-metallic precipitates and grain size on core loss of non-oriented electrical silicon steels

Science.gov (United States)

Wang, Jiayi; Ren, Qiang; Luo, Yan; Zhang, Lifeng

2018-04-01

In the current study, the number density and size of non-metallic precipitates and the size of grains on the core loss of the 50W800 non-oriented electrical silicon steel sheets were investigated. The number density and size of precipitates and grains were statistically analyzed using an automatic scanning electron microscope (ASPEX) and an optical microscope. Hypothesis models were established to reveal the physical feature for the function of grain size and precipitates on the core loss of the steel. Most precipitates in the steel were AlN particles smaller than 1 μm so that were detrimental to the core loss of the steel. These finer AlN particles distributed on the surface of the steel sheet. The relationship between the number density of precipitates (x in number/mm2 steel area) and the core loss (P1.5/50 in W/kg) was regressed as P1.5/50 = 4.150 + 0.002 x. The average grain size was approximately 25-35 μm. The relationship between the core loss and grain size (d in μm) was P1.5/50 = 3.851 + 20.001 d-1 + 60.000 d-2.

Structure change in 25 Cr - 20 Ni steels as a function of their Cr, Ni, Si and W content

International Nuclear Information System (INIS)

Gribaudo, L.M.; Durand, F.; Durand-Charre, M.

1983-01-01

The influence of varying the Cr, Ni, Si and W concentrations on the type and composition of the carbides of solidification and on the phase shift temperature is studied with 18 alloys of composition close to stainless steel-25-20 (AISI 310) composition. Experimental techniques used are differential thermal analysis, microprobe and scanning electron microscope. Crystallization is interpreted with the equilibrium diagram Ni-Cr-C. The formation of the interdendritic σ phase for a chromium rich alloys is interpreted with the phase equilibrium diagram of Fe-Ni-Cr-C. Mechanical properties and corrosion resistance are dependent on the morphology of the carbides M 7 C 3 and M 23 C 6 [fr

Effect of nitrogen alloying of stainless steels on their corrosion stability

International Nuclear Information System (INIS)

Chigal, V.; Knyazheva, V.M.; Pitter, Ya.; Babich, S.G.; Bogolyubskij, S.D.

1986-01-01

Results of corrosion tests and structural investigations of 03Cr18Ni10 and 03Cr18Ni10Mo3 steels without nitrogen and with nitrogen content of 0.15-0.3% are presented. Corrosion-electrochemical behaviour of Cr20Ni20 steel with ultralow carbon content (0.004-0.006%) and nitrogen content with 0-0.5% as well as Cr 2 N nitride behaviour are investigated. A conclusion is made on nitrogen and excessive nitride phase effect on corrosion stability of steel in corrosive media with different reduction-oxidation properties

Interaction cross-sections and matter radii of A = 20 isobars

International Nuclear Information System (INIS)

Chulkov, L.; Bochkarev, O.; Geissel, H.; Golovkov, M.; Janas, Z.; Keller, H.; Kobayashi, T.; Muenzenberg, G.; Nickel, F.; Ogloblin, A.; Patra, S.; Piechaczek, A.; Roeckl, E.; Schwab, W.; Suemmerer, K.; Suzuki, T.; Tanihata, I.; Yoshida, K.

1995-11-01

High-energy interaction cross-sections of A=20 nuclei ( 20 N, 20 O, 20 F, 20 Ne, 20 Na, 20 Mg) on carbon were measured with accuracies of ∼1%. The nuclear matter rms radii derived from the measured cross-sections show an irregular dependence on isospin projection. The largest difference in radii, which amounts to approximately 0.2 fm, has been obtained for the mirror nuclei 20 O and 20 Mg. The influenc of nuclear deformation and binding energy on the radii is discussed. By evaluating the difference in rms radii of neutron and proton distributions, evidence has been found for the existence of a proton skin for 20 Mg and of a neutron skin for 20 N. (orig.)

Report of drilling and radionuclide migration investigations at UE20n number-sign 1, Pahute Mesa, Nevada Test Site, 1987

International Nuclear Information System (INIS)

Erikson, S.J.

1991-04-01

Exploratory hole UE20n number-sign 1 was drilled 305 m down hydraulic gradient of the Cheshire event (U20n) as part of the Radionuclide Migration Program at the Nevada Test Site. The hole was designed to investigate the possibility of groundwater transport of radionuclides from the U20n cavity region. Drilling reached a total depth of 1005.8 m. Composite static water levels in the borehole were measured at approximately 620 m below ground surface. The borehole penetrated about 386 m of saturated zone, which was comprised primarily of rhyolite lava flows of the Upper Rhyolite Lavas, Tuffs, and Rhyolites of Area 20. Evidence from UE20n number-sign 1 suggests the presence of a relatively more permeable zone in the 730 to 750-m depth interval. The neutron log suggests that greater quantities of water were present at depths between 729 and 747 m. Core collected over three depth intervals showed the highest fracture density in a reddish-grey rhyolite lava flow in the 733.8 to 738.1-m core interval. Groundwater flow away from U20n through this permeable zone is suggested by the UE20n number-sign 1 borehole temperature logs. Elevated 3 H activities were observed with the highest activities found near 732 m. The 3 H activities observed in the 732 to 802-m interval in UE20n number-sign 1 were of similar magnitude to those found in the cavity region in the U20n post-shot hole. The activities of 125 Sb and 85 Kr, which are known to be mobile in groundwater, were of similar magnitude to those found near the cavity region, while 137 Cs, which is thought to be adsorbed during transport, was found in activities two to three orders of magnitude lower than near the cavity. These temperature and radioisotope data suggest that radionuclide migration via groundwater flow may be occurring laterally from the U20n rubble chimney through the permeable zone located at the 730 to 750-m depth. 25 refs., 18 figs., 15 tabs

Enhancement of strength properties of hot rolled 10KHSND steel

International Nuclear Information System (INIS)

Nasibov, A.G.; Popova, L.V.; Pikulin, S.A.; Globa, N.I.

1989-01-01

To find out the reasons of low hot rolling yield for 10KhSND steel sheets in mechanical properties, titanium effect in the range of 0.008-0.03% concentrations is studied. It is established that the titanium content in a solid solution is conserved within 0.003-0.005%, the rest of titanium is bound to carbonitrides Ti(C, N). It is shown that alloys with 0.025-0.03% titanium content possess the increased values of ultimate and yield strength the necessary level of impact strength and good wealdability. The good steel yield, when the titanium content is sustained at the given level, increases from 40 to 85%

TIC y formación web 2.0 para la inclusión social y el desarrollo sostenible

OpenAIRE

Rosanigo, Zulema Beatriz; Álvarez, Mabel; Paur, Alicia Beatriz; Dans, Marta Isabel; Gallego Gil, Domingo

2012-01-01

En este trabajo se presentan los objetivos y alcances del proyecto de investigación AP/048416/11, “TIC Y Formación Web 2.0 para la Inclusión Social y el Desarrollo Sostenible”, financiado por la Agencia Española de Cooperación Internacional para el Desarrollo (AECID) y en el que participan investigadores de Argentina, Chile, Ecuador y España.

{gamma} ray spectroscopy of neutron rich nuclei around N=20; Spectroscopie {gamma} des noyaux riches en neutrons autour de N=20

Energy Technology Data Exchange (ETDEWEB)

Gelin, M

2007-09-15

There is an island of inversion around {sup 32}Mg (12 protons, 20 neutrons) in contradiction with a shell closure N=20. It means a coexistence of spherical and deformed shapes. This work is devoted to the study of {gamma}-ray spectroscopy for nuclei in this region, based on an experiment done at GANIL with a composite secondary beam produced by fragmentation. The originality of the method used here lies in the possibility to study simultaneously several nuclei, and for each of them to explore several reaction channels. The VAMOS spectrometer was used for the identification of the ejectiles. The {gamma}-rays were detected with EXOGAM, a germanium clover array. The detectors used before and after the target allowed for a unique identification and a selection of the reaction channel: inelastic scattering, transfer and fragmentation reaction. In this thesis the following nuclei were studied: {sup 28}Ne, {sup 30-32}Mg {sup 31-34}Al, {sup 33-35}Si, {sup 35}P. New {gamma}-rays have been observed. The {gamma}-ray angular distributions and {gamma}-{gamma} angular correlations have been measured for some transitions. Assignment of spins and parities has been proposed for some states. In particular, in {sup 34}Si, the 3{sup -} assignment is confirmed and a new candidate for the second 0{sup +} has been proposed. In {sup 32}Mg, the state at 2.321 MeV, for which conflicting assignment existed, is deduced from the present data as a 4{sup +}, and a 6{sup +} state is proposed. (author)

Interaction of steel, titanium and zirconium with melted chlorides containing copper and zinc

International Nuclear Information System (INIS)

Ozeryanaya, I.N.; Manukhina, T.I.; Shibanov, B.S.

1976-01-01

Cu and Zn coatings were obtained by contact displacement of their molten chlorides. Cu was deposited on Kh18N10T stainless steel, and Zn was deposited on Ti or Zr at 400-550 0 . Cu was displaced from the electrolyte by all components in the steel. A smooth coating exhibited high adhesion. According to metallography there was a transition layer of a Ni-Cr solid solution between the surface Cu layer and steel. With electronegetiol Ti and Zr, contact deposition of Zn or Cu from chloride melts was possible. The coatings were multilayer and exhibited adequate adhesion. The coating consisted of an intermetallic compound of Ti or Zr with Zn

Effect of aging on the tribological and mechanical properties of a high-nitrogen stainless austenitic steel

International Nuclear Information System (INIS)

Korshunov, L.G.; Chernenko, N.L.; Tereshchenko, N.A.; Uvarov, A.I.

2005-01-01

The effect of aging, associated with predominant precipitation of vanadium nitrides (VN), on tribological and mechanical properties of austenitic steel 10Kh18AG18N5MF hardened from 1100 Deg C is studied. Metallographic, X-ray diffraction and electron microscopical methods are used to study structural transformations proceeding in the steel on aging as well as on friction loading under conditions of dry slipping friction in steel-abrasive and steel-steel pairs. It is shown that the aging at temperatures of 600-700 Deg C resulting in a considerable increase of strength properties of the steel demonstrates a relatively weak positive effect on steel resistance to abrasive and adhesive wear. It is stated that the use of aging by continuous mechanism permits attaining favourable mechanical and tribological properties in vanadium-alloying nitrogen-bearing austenitic steels [ru

Analysis of creep data from MOTA irradiation of 20% cold worked 316 stainless steel

International Nuclear Information System (INIS)

Garner, F.A.; Toloczko, M.B.; Puigh, R.J.

1992-01-01

The objective of this study is to provide insight into the relationship between void swelling, irradiation creep and applied stress. This insight will be used to develop irradiation creep correlations for fusion applications. Analysis of creep data for 20% cold worked 316 stainless steel irradiated in FFTF/MOTA demonstrates that creep-swelling coupling coefficient is not a strong function of temperature and can be assumed to be -0.6 x 10 -2 MPa -1 in the range 400-600 C. It appears, however, that the creep compliance B o is a moderately strong function of temperature and alloy composition. The latter dependency arises primarily because derived values of B o unavoidably incorporate precipitation-related strains that cannot be easily separated from contributions arising from true creep. It has also been found that at ∼550-600 C there is an upper limit on the total diametral strain rate at 0.33%/dpa. In contrast to the conclusion of an earlier experiment, this limitation does not arise initially from the total disappearance of creep, however. The creep rate first increases with the onset of swelling and then diminishes as the swelling rate increases, disappearing only when the swelling rate reaches its steady state value

Cr-substitution effect on structural, optical and electrical properties of Cr{sub x}Ce{sub 1−x}PO{sub 4} (x = 0.00, 0.08, 0.10 and 0.20) nanorods

Energy Technology Data Exchange (ETDEWEB)

Fadhalaoui, Amor [Laboratoire de Chimie des Matériaux, Faculté des Sciences de Bizerte, Zarzouna, Bizerte 7021 (Tunisia); Dhaouadi, Hassouna, E-mail: dhaouadihassouna@yahoo.fr [Laboratoire Matériaux Traitement et Analyse, INRAP, Technopôle Sidi-Thabet, Tunis 2020 (Tunisia); Marouani, Houda [Laboratoire de Chimie des Matériaux, Faculté des Sciences de Bizerte, Zarzouna, Bizerte 7021 (Tunisia); Kouki, Abdessalem [L3M, FSB, Zarzouna, Bizerte 7021 (Tunisia); Madani, Adel [Department of Physics, Applied Science College, Umm Al Qura University, Makkah (Saudi Arabia); Rzaigui, Mohamed [Laboratoire de Chimie des Matériaux, Faculté des Sciences de Bizerte, Zarzouna, Bizerte 7021 (Tunisia)

2016-01-15

Graphical abstract: The Cr{sub x}Ce{sub 1−x}PO{sub 4} (x = 0.00, 0.08, 0.10 and 0.20) nanorods synthesized under hydrothermal conditions. - Highlights: • Cr{sub x}Ce{sub 1−x}PO{sub 4} (x = 0.00–0.20) nanorods were synthesized by hydrothermal method. • Mean crystallite size of the products decreases with Cr-content. • Obvious improvements of the electrical conductivity comparatively to CePO4. - Abstract: Cr{sub x}Ce{sub 1−x}PO{sub 4} (x = 0.00–0.20) nanorods were synthesized using the hydrothermal method. The as-prepared samples were characterized by X-ray diffraction (XRD), infrared absorption spectroscopy (IR) and transmission electron microscopy (TEM). The XRD results revealed the formation of a pure CePO{sub 4} hexagonal phase. TEM images confirmed the nano-size character of the as-prepared samples. Impedance spectroscopy analysis was used to analyze the electrical behavior of samples as a function of frequency at different temperatures. The increase of Cr-amount led to an increase in the total conductivities and decreased the activation energies (E{sub a} (x = 0.00) = 1.08 eV to E{sub a} (x = 0.20) = 0.80 eV). The optical properties of Cr{sub x}Ce{sub 1−x}PO{sub 4} nanomaterials were investigated using UV–vis spectroscopy. The band-gap energy values decreased with increasing Cr-content showing a red-shift trend. The improvement of the electrical conductivity and optical properties makes the Cr{sub x}Ce{sub 1−x}PO{sub 4} nanomaterials possible candidates to be used as electrolytes in solid oxide fuel cells, in photocatalytic and photovoltaic applications.

Mechanism of APC/CCDC20 activation by mitotic phosphorylation.

Science.gov (United States)

Qiao, Renping; Weissmann, Florian; Yamaguchi, Masaya; Brown, Nicholas G; VanderLinden, Ryan; Imre, Richard; Jarvis, Marc A; Brunner, Michael R; Davidson, Iain F; Litos, Gabriele; Haselbach, David; Mechtler, Karl; Stark, Holger; Schulman, Brenda A; Peters, Jan-Michael

2016-05-10

Chromosome segregation and mitotic exit are initiated by the 1.2-MDa ubiquitin ligase APC/C (anaphase-promoting complex/cyclosome) and its coactivator CDC20 (cell division cycle 20). To avoid chromosome missegregation, APC/C(CDC20) activation is tightly controlled. CDC20 only associates with APC/C in mitosis when APC/C has become phosphorylated and is further inhibited by a mitotic checkpoint complex until all chromosomes are bioriented on the spindle. APC/C contains 14 different types of subunits, most of which are phosphorylated in mitosis on multiple sites. However, it is unknown which of these phospho-sites enable APC/C(CDC20) activation and by which mechanism. Here we have identified 68 evolutionarily conserved mitotic phospho-sites on human APC/C bound to CDC20 and have used the biGBac technique to generate 47 APC/C mutants in which either all 68 sites or subsets of them were replaced by nonphosphorylatable or phospho-mimicking residues. The characterization of these complexes in substrate ubiquitination and degradation assays indicates that phosphorylation of an N-terminal loop region in APC1 is sufficient for binding and activation of APC/C by CDC20. Deletion of the N-terminal APC1 loop enables APC/C(CDC20) activation in the absence of mitotic phosphorylation or phospho-mimicking mutations. These results indicate that binding of CDC20 to APC/C is normally prevented by an autoinhibitory loop in APC1 and that its mitotic phosphorylation relieves this inhibition. The predicted location of the N-terminal APC1 loop implies that this loop controls interactions between the N-terminal domain of CDC20 and APC1 and APC8. These results reveal how APC/C phosphorylation enables CDC20 to bind and activate the APC/C in mitosis.

The Chandra Source Catalog 2.0: Estimating Source Fluxes

Science.gov (United States)

Primini, Francis Anthony; Allen, Christopher E.; Miller, Joseph; Anderson, Craig S.; Budynkiewicz, Jamie A.; Burke, Douglas; Chen, Judy C.; Civano, Francesca Maria; D'Abrusco, Raffaele; Doe, Stephen M.; Evans, Ian N.; Evans, Janet D.; Fabbiano, Giuseppina; Gibbs, Danny G., II; Glotfelty, Kenny J.; Graessle, Dale E.; Grier, John D.; Hain, Roger; Hall, Diane M.; Harbo, Peter N.; Houck, John C.; Lauer, Jennifer L.; Laurino, Omar; Lee, Nicholas P.; Martínez-Galarza, Juan Rafael; McCollough, Michael L.; McDowell, Jonathan C.; McLaughlin, Warren; Morgan, Douglas L.; Mossman, Amy E.; Nguyen, Dan T.; Nichols, Joy S.; Nowak, Michael A.; Paxson, Charles; Plummer, David A.; Rots, Arnold H.; Siemiginowska, Aneta; Sundheim, Beth A.; Tibbetts, Michael; Van Stone, David W.; Zografou, Panagoula

2018-01-01

The Second Chandra Source Catalog (CSC2.0) will provide information on approximately 316,000 point or compact extended x-ray sources, derived from over 10,000 ACIS and HRC-I imaging observations available in the public archive at the end of 2014. As in the previous catalog release (CSC1.1), fluxes for these sources will be determined separately from source detection, using a Bayesian formalism that accounts for background, spatial resolution effects, and contamination from nearby sources. However, the CSC2.0 procedure differs from that used in CSC1.1 in three important aspects. First, for sources in crowded regions in which photometric apertures overlap, fluxes are determined jointly, using an extension of the CSC1.1 algorithm, as discussed in Primini & Kashyap (2014ApJ...796…24P). Second, an MCMC procedure is used to estimate marginalized posterior probability distributions for source fluxes. Finally, for sources observed in multiple observations, a Bayesian Blocks algorithm (Scargle, et al. 2013ApJ...764..167S) is used to group observations into blocks of constant source flux.In this poster we present details of the CSC2.0 photometry algorithms and illustrate their performance in actual CSC2.0 datasets.This work has been supported by NASA under contract NAS 8-03060 to the Smithsonian Astrophysical Observatory for operation of the Chandra X-ray Center.

On superplasticity of corrosion resistant ferritic-austenitic chromium-nickel steels

Energy Technology Data Exchange (ETDEWEB)

Surovtsev, A P; Sukhanov, V E

1988-01-01

The deformability of corrosion resistant chromium-nickel ferritic austenitic steel type O8Kh22N6T under tension, upsetting and torsion in the 600-1200 deg C temperature range is studied. For the deformation rate of the order of 10/sup -3/ s/sup -1/ the effect of superelasticity reveals itself at 850 deg C in the process of ferrite dynamic polymerization, in the 925-950 deg C range, at initial stages of dynamic recrystallization - the dynamic polygonization controlled by chromium carbide dissolving in steel and maximum at 1050 deg C in the process of development of austenite dynamic recrystallization with grain refinement with F/A ratio equalling 1. After upsetting in the elasticity mode at 1050 deg C the impact strength of the above steel is maximum.

Ciencia 2.0

OpenAIRE

Lafuente, Antonio

2006-01-01

El fraude en ciencia viene siendo un motivo de creciente preocupación entre los editores y políticos de la ciencia. Y, entre las muchas alternativas que se proponen, se hace necesario explorar las nuevas posibilidades que ofrecen las llamadas tecnologías de la web 2.0 y las prácticas utilizadas en el movimiento open source.

Surface deformation effects on stainless steel, Ni, Cu and Mo produced by medium energy He ions irradiation

International Nuclear Information System (INIS)

Constantinescu, B.; Florescu, V.; Sarbu, C.

1993-01-01

To investigate dose and energy dependence of surface deformation effects (blistering and flaking), different kinds of candidate CTR first wall materials as 12KH18N10T, W-4541, W-4016 and SS-304 stainless steels, Ni, Cu, Mo were irradiated at room temperature with 3.0, 4.7 and 6.8 MeV He + ions at IAP Cyclotron. The effects were investigated by means of a TEMSCAN 200 CX electron microscope and two metallographic Orthoplan Pol Leitz and Olympus microscopes. We observed two dose dependent main phenomena: blistering and flaking (craters). So, blisters occurrence on the irradiated surface is almost instantaneous when a critical dose (number of He ions accumulated in the region at the end of alpha particles range) is reached. Increasing irradiation dose, we reached flaking stage. So, isolated submicronic fissures along grain boundaries were observed on the blister skin, chronologically followed by large (5-20 μm) deep cracks of hundreds of microns in length, blisters opening and, finally, flaking appearance. (author) 8 figs., 1 tab

High Temperature Tensile Properties of Unirradiated and Neutron Irradiated 20 Cr-35 Ni Austenitic Steel

Energy Technology Data Exchange (ETDEWEB)

Roy, R B; Solly, B

1966-12-15

The tensile properties of an unirradiated and neutron irradiated (at 40 deg C) 20 % Cr, 35 % Ni austenitic steel have been studied at 650 deg C, 750 deg C and 820 deg C. The tensile elongation and mode of fracture (transgranular) of unirradiated specimens tested at room temperature and 650 deg C are almost identical. At 750 deg C and 820 deg C the elongation decreases considerably and a large part of the total elongation is non-uniform. Furthermore, the mode of fracture at these temperatures is intergranular and microscopic evidence suggests that fracture is caused by formation and linkup of grain boundary cavities. YS and UTS decrease monotonically with temperature. Irradiated specimens show a further decrease in ductility and an increase in the tendency to grain boundary cracking. Irradiation has no significant effect on the YS, but the UTS are reduced. The embrittlement of the irradiated specimens is attributed to the presence of He and Li atoms produced during irradiation and the possible mechanisms are discussed. Prolonged annealing of irradiated and unirradiated specimens at 650 deg C appears to have no significant effect on tensile properties.

20 CFR 228.20 - Reduction for an employee annuity.

Science.gov (United States)

2010-04-01

... 20 Employees' Benefits 1 2010-04-01 2010-04-01 false Reduction for an employee annuity. 228.20... COMPUTATION OF SURVIVOR ANNUITIES The Tier I Annuity Component § 228.20 Reduction for an employee annuity. (a) General. If an individual is entitled to an annuity as a survivor, and is also entitled to an employee...

Evaluation of 235U(n,f) between 100 keV and 20 MeV

International Nuclear Information System (INIS)

Poenitz, W.P.

1979-07-01

The 235 U(n,f) cross section is evaluated in the energy range from 100 keV to 20 MeV. Experimental data are included up to the 1978 Harwell Conference on Neutron Physics. The evaluation methodology is discussed in detail. The shape and the normalization of the cross section are evalutated in separate steps. An extensive comparison of the evaluation result with experimental data sets is made. The shape of the cross section obtained in a preliminary version of the present evaluation and a normalization factor extracted from data provided within the framework of this evaluation were used by the Subcommittee on Standards and Normalizations of the Cross Sections Evaluation Working Group to establish 235 U(n,f) for ENDF/B-V above 100 keV. 20 figures, 6 tables

Developing of complex for hot plastic deformation modeling of steel type 20-30CrNiMoV for heavy forging

Directory of Open Access Journals (Sweden)

Dub Vladimir

2017-01-01

Full Text Available Production of heavy forging of bars weighing more then 235 tons for such products as rotors made of steel type 20-30CrNiMoV is a critical independent work, failure to perform which entails high costs related to repeated production (in case of defective product and untimely launch of production plants. One of the frequent causes of a defective product is the impossibility of ultrasonic testing in the barrel-gate zones on the rotor workpiece, which is due to the microstructure of the metal, namely the grain size. Determing the stages of deformation process wich causes such defects in structure is the main goal of this work.

Portal WEB 2.0. utilizando Framework Struts

OpenAIRE

Palacín Mateo, Manuel

2007-01-01

El propósito de este proyecto es la implementación de un portal interactivo de contactos utilizando las tecnologías J2EE mediante Struts y siguiendo la tendencia Web 2.0. Previo a esta implementación se ha hecho una valoración del mercado actual de los portales de contactos y se han evaluado los servicios que ofrecen para posteriormente añadirlos a la demostración tecnológica. Tras esto se ha explicado lo que es la tendencia Web 2.0. Finalmente se han evaluado las diferentes opciones o tec...

AirBase - A database of 160,000 aerial photos of Greenland 1930-1980s

Science.gov (United States)

Korsgaard, Niels; Weng, Willy L.; Kjær, Kurt H.

2017-04-01

. Mass balance of the Greenland ice sheet from 1958 to 2007. Geophys. Res. Lett. (2008. (5) Kjær, K.H., Khan, S.A., Korsgaard, N.J., Wahr, J., Bamber, J.L., Hurkmans, R., van den Broeke, M., Timm, L.H., Kjeldsen, K.K., Bjørk, A.A., Larsen, N.K., Jørgensen, L.T., Færch-Jensen, A. & Willerslev, E. Aerial Photographs Reveal Late-20th-Century Dynamic Ice Loss in Northwestern Greenland. Science 337 (2012). (6) Bjørk, A.A., Kjær, K.H., Korsgaard, N.J., Khan, S.A., Kjeldsen, K.K., Andresen, C.S., Box, J, Larsen, N.K. & Funder, S.V. An aerial view of 80 years of climate-related glacier fluctuations in southeast Greenland. Nat. Geosci. 5 (2012). (7) Kjeldsen, K.K., Korsgaard, N.J., Bjørk, A.A., Khan, S.A., Box, J.E., Funder, S., Larsen, N.K., Bamber, J.L., Colgan, W., van den Broeke, M., Siggaard-Andersen, M.-L., Nuth, C., Schomacker, A., Andresen, C.S., Willerslev, E. & Kjær, K.H. Spatial and temporal distribution of mass loss from the Greenland Ice Sheet since AD 1900. Nature 528 (2015). (8) Korsgaard, N.J., Nuth, C., Khan, S.A., Kjeldsen, K.K., Bjørk, A.A., Schomacker A. & Kjær, K.H. Digital elevation model and orthophotographs of Greenland based on aerial photographs from 1978-1987. Sci. Data 3:160032 (2016).

Investigations on the Behavior of HVOF and Cold Sprayed Ni-20Cr Coating on T22 Boiler Steel in Actual Boiler Environment

Science.gov (United States)

Bala, Niraj; Singh, Harpreet; Prakash, Satya; Karthikeyan, J.

2012-01-01

High temperature corrosion accompanied by erosion is a severe problem, which may result in premature failure of the boiler tubes. One countermeasure to overcome this problem is the use of thermal spray protective coatings. In the current investigation high velocity oxy-fuel (HVOF) and cold spray processes have been used to deposit commercial Ni-20Cr powder on T22 boiler steel. To evaluate the performance of the coatings in actual conditions the bare as well as the coated steels were subjected to cyclic exposures, in the superheater zone of a coal fired boiler for 15 cycles. The weight change and thickness loss data were used to establish kinetics of the erosion-corrosion. X-ray diffraction, surface and cross-sectional field emission scanning electron microscope/energy dispersive spectroscopy (FE-SEM/EDS) and x-ray mapping techniques were used to analyse the as-sprayed and corroded specimens. The HVOF sprayed coating performed better than its cold sprayed counterpart in actual boiler environment.

Effect of quenching temperature on martensite multi-level microstructures and properties of strength and toughness in 20CrNi2Mo steel

Energy Technology Data Exchange (ETDEWEB)

Long, Shao-lei [College of Materials Science and Metallurgical Engineering, Guizhou University (China); Guizhou Key Laboratory for Mechanical Behavior and Microstructure of Materials (China); National & Local Joint Engineering Laboratory for High-performance Metal Structure Material and Advanced Manufacturing Technology (China); Liang, Yi-long, E-mail: liangyilong@126.com [College of Materials Science and Metallurgical Engineering, Guizhou University (China); Guizhou Key Laboratory for Mechanical Behavior and Microstructure of Materials (China); National & Local Joint Engineering Laboratory for High-performance Metal Structure Material and Advanced Manufacturing Technology (China); Jiang, Yun [Guizhou Key Laboratory for Mechanical Behavior and Microstructure of Materials (China); National & Local Joint Engineering Laboratory for High-performance Metal Structure Material and Advanced Manufacturing Technology (China); Liang, Yu; Yang, Ming; Yi, Yan-liang [College of Materials Science and Metallurgical Engineering, Guizhou University (China); Guizhou Key Laboratory for Mechanical Behavior and Microstructure of Materials (China); National & Local Joint Engineering Laboratory for High-performance Metal Structure Material and Advanced Manufacturing Technology (China)

2016-10-31

The martensite multi-level microstructures of 20CrNi2Mo steel, which were quenched at the different temperatures of 900–1200 °C and tempered at 200 °C, were investigated by optical microscope (OM), scanning electron microscopy (SEM), electron backscattering diffraction (EBSD) and transmission electron microscopy (TEM), and the relationship between the microstructures and properties of strength and toughness was discussed by the classic formula of Hall–Petch. The results show that the size of prior austenite grain (d{sub r}), martensite packet (d{sub p}) and block (d{sub b}) increase with increasing of the quenching temperature, while the martensite lath (d{sub l}) size is opposite. On another hand, the confusion degree of the martensite packets changes from disorder to order. The boundaries of prior austenite grain, packet, block and the martensite lath are high angle boundaries (HBs) and low angle boundaries (LBs), respectively, and the ratio of the low angle boundaries increase with the quenching temperature by calculating to the multi-level microstructure size with the mathematical model established by myself. In addition, the relationship between the packet/block and strength follows the classical formula of Hall–Petch, and the size of d{sub b} is far lower than the size of d{sub p}, d{sub b} is the effective control unit of the strength. Meanwhile, d{sub l} is the effective control unit of toughness because it strongly impacts the crack initiation and propagation and follows also the Hall-Petch with toughness in 20CrNi2Mo steel.

20 CFR 418.1105 - What is the threshold?

Science.gov (United States)

2010-04-01

... 20 Employees' Benefits 2 2010-04-01 2010-04-01 false What is the threshold? 418.1105 Section 418.1105 Employees' Benefits SOCIAL SECURITY ADMINISTRATION MEDICARE SUBSIDIES Medicare Part B Income... in the Consumer Price Index rounded to the nearest $1,000. CMS will publish the threshold amounts...

Biological effect of 20 keV N+ ion implantation on Stevia rebaudianum

International Nuclear Information System (INIS)

Su Tingting; Yang Tingting; Ji Guohong; Xiang Xingjia; Chen Xuetao; Wang Yu; Wu Yaojin

2010-01-01

The germinability and gemination rate of Stevia rebaudianum seeds implanted with 20 keV N + ions in doses of 0 (CK), 100 x 2500, 400 x 2500 and 1000 x 2500 N + /cm 2 were studied by analyzing the differences in seed germinability and gemination rate between the groups. By statistical analysis, the germinability and gemination rate were affected at the level of α=0.05 by the implantation dose. The results showed that the germinability and gemination rate increased with the dose first and then decreased. At 400 x 2500 N + /cm 2 , the seeds had the largest germinability and the gemination rate. (authors)

Steam oxidation of X20CrMoV121: Comparison of laboratory exposures and in situ exposure in power plants

DEFF Research Database (Denmark)

Montgomery, M.; Hansson, A. N.; Vilhelmsen, T.

2012-01-01

X20CrMoV121 is a 12% Cr martensitic steel which has been used in power plants in Europe for many decades. Specimens have been removed from superheater tubes to investigate long‐term exposure with respect to steam oxidation. These tubes have been exposed for various durations up to 135 000 h...... in power plants in Denmark at steam temperatures varying from 450–565 °C. This paper collates the data, compares oxide morphologies and assesses to what extent parabolic kinetics can be used to describe the oxidation rate. The steam oxidation behaviour has been investigated in the laboratory in an Ar‐46%H2...

Corrosión por depósitos salinos de los aceros SA213-T22 y SA213-TP347H en presencia de una mezcla 80%V2O5-20%Na2SO4-20%Na2SO4

Directory of Open Access Journals (Sweden)

Romero, M. A.

1998-02-01

Full Text Available Many hot corrosion problems in industrial and utility boilers are caused by molten salts. The corrosion processes which occur in salts are of an electrochemical nature, and so they can be studied using electrochemical test methods. In this research, electrochemical techniques in molten salt systems have been used for the measurements of molten corrosion processes. Electrochemical test methods are described here for a salt mixture of 80%V2O5-20%Na2SO4 at 540-680°C. To establish better the electrochemical corrosion rate mearurements for molten salt systems, information from electrochemical potentiodynamic polarization curves, such as polarization resistance and Tafel slopes were used in this study to generate corrosion rate data. The salt was contained in a quartz crucible inside a stainless steel retort. The atmosphere used was air. A thermocouple sheathed with quartz glass was introduced into the molten salt for temperature monitoring and control. Two materials were tested in the molten mixture: SA213-T22 and SA213-TP347H steels. The corrosion rates values obtained using electrochemical methods were around 0.58-7.14 mm/yr (22.9-281 mpy. The corrosion rate increase with time.Muchos problemas de corrosión por depósitos salinos en la industria eléctrica, especialmente en los generadores de vapor, se deben al ataque por sales fundidas. El proceso de corrosión en sales fundidas es de naturaleza electroquímica; así, puede estudiarse empleando técnicas electroquímicas. Este proceso de corrosión en un sistema de sales fundidas, mezcla de 80%V2O5 y 20%Na2SO4 a temperaturas comprendidas entre 540 y 680°C, se evaluó en esta investigación por medio de técnicas electroquímicas. Para medir la velocidad de corrosión por depósitos salinos se parte de curvas de polarización potenciodinámicas determinando la resistencia de polarización por extrapolación de las pendientes de Tafel. Las sales se fundieron en un crisol de cuarzo dentro de un

Deep-sea benthic foraminiferal record of the paleoceanography in the southern Okinawa Trough over the last 20 000 years

Institute of Scientific and Technical Information of China (English)

翦知湣; 陈荣华; 李保华

1996-01-01

Quantitative analyses have been carried out on benthic foraminifera from 66 samples of Core 255 in the southern Okinawa Trough, in combination with the stable isotopic analyses of planktonic and benthic foraminifera and AMS 14C dating, in order to reconstruct the history of change under deep water conditions and surface paleoproduclivity over the last 20 000 years. The variations in the ratio of agglutinants in benthic foraminiferal fauna and the ratio of fragments in planktonic foraminifera] fauna indicate higher carbonate dissolution during the postglacial stage than during the glacial stage. The distribution of species and the results of Q-mode factor analysis show that there are three distinctly different benthic foraminiferal assemblages during the glacial, deglacial and postglacial stages in the Okinawa Trough over the last 20000 years: the glacial Bulimina aculeata assemblage (especially the dominant species Uvigerina pereyrina) is associated with high surface primary productivity and organic mat

Effect of reactor irradiation on long-term strength and creep of 0Kh16N15M3B steel under plane stressed state

International Nuclear Information System (INIS)

Khristov, G.P.; Kosov, B.D.

1982-01-01

The paper deals with analysis of results of experimental studies in creep of the austenitic OKh16n15m3b steel with various size of initial-structure grain under conditions of high-intensity reactor irradiation and control tests. It is suggested to consider the material initial structure effect on intensity of minimum creep rates both under ordinary and intrareactor conditions of loading by means of the function grain size effect on the equivalent stress. It is shown that the criterial expression previously suggested by the authors is invariant to the type of stressed and structural states and relative to intensity of minimal creep rates. It is established that the creep rate of the irradiated steel may be calculated from dependence for nonirradiated steel using as an argument a certain reduced equivalent stress which is a function of the acting stress and irradiation parameter

Bibliotecas de Nueva Generación (Biblioteca 2.0)

OpenAIRE

González-Fernández-Villavicencio, Nieves

2007-01-01

This article study the definition of "Library 2.0" and describes implications for all types of libraries inside and outside Spain, with special attention to Seville University library. The paper focusses on the practice of librarianship, specifically addressing how Web 2.0 technologies such as synchronous messaging and streaming media, blogs, wikis, social networks, tagging, RSS feeds, and mashups are changing how libraries provide access to their collections and user support for that access.

Presos 2.0: comunicación y TIC’s en contextos de encarcelamiento

OpenAIRE

María Antonieta Elvira-Valdés

2014-01-01

El ser humano es social por naturaleza y, como tal, es un ser comunicante. La evolución y complejidad de cada sociedad se inscribe en el desarrollo y transformación de sus medios de comunicación. La web 2.0 integra y participa en los cambios que se han producido en los procesos comunicativos. Desde la Teoría de Usos y Gratificaciones de Eliu Katz, se propone la selección y uso de los medios que hacen las personas en la búsqueda de satisfacer sus necesidades; las nuevas Tecnologías de Informac...

Purification, crystallization and preliminary X-ray diffraction analysis of the IL-20-IL-20R1-IL-20R2 complex

Energy Technology Data Exchange (ETDEWEB)

Logsdon, Naomi J.; Allen, Christopher E.; Rajashankar, Kanagalaghatta R.; Walter, Mark R. (Cornell); (UAB)

2012-02-08

Interleukin-20 (IL-20) is an IL-10-family cytokine that regulates innate and adaptive immunity in skin and other tissues. In addition to protecting the host from various external pathogens, dysregulated IL-20 signaling has been shown to contribute to the pathogenesis of human psoriasis. IL-20 signals through two cell-surface receptor heterodimers, IL-20R1-IL-20R2 and IL-22R1-IL-20R2. In this report, crystals of the IL-20-IL-20R1-IL-20R2 ternary complex have been grown from polyethylene glycol solutions. The crystals belonged to space group P4{sub 1}2{sub 1}2 or P4{sub 3}2{sub 1}2, with unit-cell parameters a = 111, c = 135 {angstrom}, and diffracted X-rays to 3 {angstrom} resolution. The crystallographic asymmetric unit contains one IL-20-IL-20R1-IL-20R2 complex, corresponding to a solvent content of approximately 54%.

New method for NPP sodium coolant pipeline austenization

International Nuclear Information System (INIS)

Malashonok, V.A.; Rotshtejn, A.V.; Gotshalk, A.L.; Miryushchenko, E.F.

1980-01-01

Heat treatment technology is considered for pipelines intended for the NPP cooling systems employing sodium coolant. Various techniques are discussed which are used for protecting the pipeline internal surfaces against oxidation in the process of heat treatment. It is noted that the austenite formation of welded joints of steel 12Kh18N9 and steel Kh16N11M3 at temperatures of 1050 and 1100 deg C releases welding-induced stresses and reduces a possibility of local damages. Evacuation down to 1 mm Hg appears to be the most rational protective technique. The considered procedure of the pipeline heat treatment has been utilized for mounting the equipment of the BN-600 reactor at the Beloyarskaya NPP. The economic gain resulting from the use of the procedure, owing to decrease in argon consumption and reduction of labour input, makes up 150 000 roubles

Kankaan tuotekehittäminen erikoisolosuhteisiin K&H Annala Oy:lle

OpenAIRE

Koski, Marjo

2017-01-01

Opinnäytetyö tehtiin yhteistyössä Suomen ainoan huonekalukankaita valmistavan yrityksen K&H Annala Oy:n kanssa. Työn aiheena oli suunnitella ja tuotteistaa kangasmallisto erikoisolosuhteisiin innovatiivisesta, Italiassa valmistettavasta Flyer-langasta. Projektin lähtökohtana oli opinnäytetyöntekijän kasvava kiinnostuneisuus kudottuja tekstiilejä kohtaan ja kankaan suunnitteluprosessin vieminen teollisen tuotannon puolelle. Projektissa tähdättiin uudentyyppiseen kankaaseen ilmeen ja materiaali...

Influence of ion implanted helium on deuterium trapping in Kh18N10T stainless steel

International Nuclear Information System (INIS)

Tolstolutskaya, G.D.; Ruzhitskij, V.V.; Kopanets, I.E.

2004-01-01

The results are presented on evolution of distribution profiles and helium and deuterium thermal desorption ion implanted in steel 18Cr10NiTi. Accumulation, trapping, retention and microstructure evolution are studied; effect helium and hydrogen simultaneous implantation on these processes is also studied

Influence of time presetting procedure for rapid local heat;.ng on brazing temperature conditions

International Nuclear Information System (INIS)

Lezhnin, G.P.; Tul'skikh, V.E.

1985-01-01

Correlation of known and suggested presetting procedures for heating period during induction brazing was conducted. It is shown that brazing time must be established considering heat propagation during heating in order to obtain the assigned joint temperature regardless of heating rate change. Methods for temperature calculation in assigned zones of the joint are suggested. The suggested presetting procedure for heating time was applied for induction vacuum brazing of a tube of 12Kh18N10T steel to a pipe connection of VT20 alloy

TUMOR PHYLLODES DE LA MAMA.CARACTERIZACIÓN EN LA PROVINCIA CIENFUEGOS.ESTUDIO DE 20 AÑOS

Directory of Open Access Journals (Sweden)

Lidia Torres Aja

2007-01-01

Full Text Available El tumor Phyllodes de la mama es poco frecuente. Tiene un origen fibroepitelial con potencial agresivo y representa el 0.3% a 0.4% de todos los tumores mamarios y el 2.5% a 3% de los tumores epiteliales de dicho órgano.Objetivo: Nuestro objetivo fundamental es caracterizar desde el punto de vista clínico patológico los tumores Phyllodes operados en la provincia de Cienfuegos durante 20 años.Tipo de estudio: descriptivo prospectivo observacional. Periodo evaluado: 20 años desde 1 de enero de 1987 hasta el 31 de diciembre del 2006. Universo: 57 pacientes.Métodos: para realizar nuestra investigación hemos seguido anualmente durante estos 20 años los casos operados en nuestra provincia, examinando personalmente los casos en consulta de Mastología antes de operarlos y siguiéndolo por consulta de operados durante más de 5 añosResultados fundamentales: como resultados fundamentales de nuestra investigación obtuvimos que se operaron en esos 20 años un total de 57 tumores Phyllodes, los cuales representaron el 2.9% del total de tumores fibroepiteliales de mama operados.Aunque el mayor número de casos se detectó en pacientes de más de 40 años, queremos resaltar que en este periodo se operaron los únicos tumores Phyllodes en niña y en adolescente reportados en nuestra provincia

G20 jagas ümber jõujooni IMFis / Katri Soe-Surén

Index Scriptorium Estoniae

Soe-Surén, Katri

2010-01-01

G20 finantsliidrid jõudsid Lõuna-Koreas toimunud kohtumisel kokkuleppele, et Lääne-Euroopa jääb reformi tulemusel ilma küll kahest kohast IMF-i direktorite nõukogus, kuid säilitab siiski oma ülekaalu. Säilib ka USA vetoõigus võtmeotsuste tegemisel. Otsustati loobuda konkreetsetest eksporditurgude reguleeringust

20 CFR 901.20 - Standards of performance of actuarial services.

Science.gov (United States)

2010-04-01

... services. 901.20 Section 901.20 Employees' Benefits JOINT BOARD FOR THE ENROLLMENT OF ACTUARIES REGULATIONS... Standards of Performance for Enrolled Actuaries § 901.20 Standards of performance of actuarial services. In the discharge of duties required by ERISA of enrolled actuaries with respect to any plan to which the...

Remediation of 20,000 m3 of hydrocarbon-impacted soil at a former well site using the biopile process

Energy Technology Data Exchange (ETDEWEB)

Bedard, G. [Biogenie Inc., Calgary, AB (Canada)

2006-07-01

The remediation of 20,000 m{sup 3} of hydrocarbon-impacted soil at a former well site using the biopile process was discussed. The site involved was an abandoned site located southwest from Red Deer, Alberta in an agricultural area. The presentation provided background on the site history and discussed an additional site assessment. The objectives of this assessment were to complete the delineation of the hydrocarbon plume; confirm the depth of impact identified in a previous environmental assessment; and, select the most efficient remediation strategy. The presentation also discussed findings of the Environmental Services Association (ESA). Site specific challenges that were addressed included proximity of land owners; lease slopes to a nearby river; large volume of impacted material; depth of impact; limited space available on-site; high concentrations of petroleum hydrocarbons (PHCs); segregation of impacted soil; and winter installation and start-up. The proposed strategy and its advantages as well as the methodology for the remediation strategy were all discussed. 5 tabs., 5 figs.

Comparative assessment of filler wires for argon-arc welding of refractory alloys

International Nuclear Information System (INIS)

Sorokin, L.I.; Bagdasarov, Yu.S.; Tupikin, V.I.

1993-01-01

It is recommended to use wires of similar composition as filler material during argon-arc welding of heat resisting alloys, and Sv-08Kh20N57M8V8T3R wire - for welding of dispersion hardening alloys. Sv-06Kh15N60M15, Sv-KhN64KBMYuVF or Kh11N60M23 wires should be used as filler materials to decrease tendency of welded joints to cracking during welding and heat treatment

Hot deformation effect on the kinetics of austenite transformation under continuous cooling conditions

International Nuclear Information System (INIS)

Bernshtejn, M.L.; Zajmovskij, V.A.; Kisteh, N.V.; Samedov, O.V.; Faldin, S.A.

1979-01-01

The effect of hot deformation on the kinetics of austenite transformations in the commercial 4040Kh 40KhN, and 40KhNMA steels on continuous cooling was studied. The transformations were studied using a dilatometer of a special design which permits a specimen to be fixed quickly in holders after hot deformation. It is stated that in hot-deformed austenite the pearlite transformation proceeds at higher temperatures and in a narrower temperature range. Austenite deformation provides an opportunity to obtain a more fine ferrite-pearlite structure and ensures a uniform distribution of a structurally free ferrite in the steel bulk. The effect of hot deformation on the structure of ferrite decomposition products in the 40KhN and 40KhNMA steels is more complicated, which is connected with a substantial change in the kinetics of pearlite and intermediate transformations

Peptide IC-20, encoded by skin kininogen-1 of the European yellow-bellied toad, Bombina variegata, antagonizes bradykinin-induced arterial smooth muscle relaxation

Directory of Open Access Journals (Sweden)

Mu Yang

2011-01-01

Full Text Available Objectives: The objectives were to determine if the skin secretion of the European yellow-bellied toad (Bombina variegata, in common with other related species, contains a bradykinin inhibitor peptide and to isolate and structurally characterize this peptide. Materials and Methods: Lyophilized skin secretion obtained from this toad was subjected to reverse phase HPLC fractionation with subsequent bioassay of fractions for antagonism of the bradykinin activity using an isolated rat tail artery smooth muscle preparation. Subsequently, the primary structure of the peptide was established by a combination of microsequencing, mass spectroscopy, and molecular cloning, following which a synthetic replicate was chemically synthesised for bioassay. Results: A single peptide of molecular mass 2300.92 Da was resolved in HPLC fractions of skin secretion and its primary structure determined as IYNAIWP-KH-NK-KPGLL-. Database interrogation with this sequence indicated that this peptide was encoded by skin kininogen-1 previously cloned from B. variegata. The blank cycles were occupied by cysteinyl (C residues and the peptide was located toward the C-terminus of the skin kininogen, and flanked N-terminally by a classical -KR- propeptide convertase processing site. The peptide was named IC-20 in accordance (I = N-terminal isoleucine, C = C-terminal cysteine, 20 = number of residues. Like the natural peptide, its synthetic replicate displayed an antagonism of bradykinin-induced arterial smooth muscle relaxation. Conclusion: IC-20 represents a novel bradykinin antagonizing peptide from amphibian skin secretions and is the third such peptide found to be co-encoded with bradykinins within skin kininogens.

Study of strength of Dsub(y)150 gate valve case, manufactured by centrifugal casting

International Nuclear Information System (INIS)

Umanskaya, L.G.; Semenov, P.V.; Tinyakov, V.G.; Babkina, R.I.; Khatuntsev, Eh.V.

1982-01-01

A process for manufacturing centrifugal-cast gate valve body is developed. Structural strength of such items, homogeneity, ductile and strength properties over the cross section as well as the metal susceptibility to embrittlement have been investigated. Three cast gate valve bodies have been taken: one - of 20GSL steel - for hydraulic testing, and two - of 15Kh1MFL steel - for investigation into the metal properties across the valve thickness. The strength properties of the centrifugal-cast gate valve body of 15Kh1M1FL steel are stated to meet the specifications. The gate valve metal ductility (delta and PSI) is twice as high as that of a sand-cast valve. The microstructure, strength and ductility are uniform both over wall thickness and over different body cross sections

20 years PSI accelerator. The speeches; 20 Jahre PSI-Beschleuniger. Die Festreden

Energy Technology Data Exchange (ETDEWEB)

NONE

1994-12-31

This publication contains the text of four papers presented at the occasion of the 20 year Symposium of the PSI accelerator. The papers dealt with the following topics: Scientific research and its dual interaction with industry and with the general public, the history of the PSI accelerator, {mu}-n-{gamma} investigations on high temperature superconductors, therapy with charged particles. figs., tabs., refs.

Potential energy surfaces for N = Z, 20Ne-112Ba nuclei

International Nuclear Information System (INIS)

Mehta, M.S.; Gupta, Raj K.; Jha, T.K.; Patra, S.K.

2004-01-01

We have calculated the potential energy surfaces for N = Z, 20 Ne- 112 Ba nuclei in an axially deformed relativistic mean field approach. A quadratic constraint scheme is applied to determine the complete energy surface for a wide range of the quadrupole deformation. The NL3, NL-RAl and TM1 parameter sets are used. The phenomenon of (multiple) shape coexistence is studied and the calculated ground and excited state binding energies, quadrupole deformation parameters and root mean square (rms) charge radii are compared with the available experimental data and other theoretical predictions. (author)

Magnetic performance of DEVU25.20h undulator at IDDL, DAVV,India

Science.gov (United States)

Mishra, G.; Gehlot, Mona; Sharma, Geetanjali; Khullar, Roma

2016-10-01

In this paper, we describe the design development and magnetic performance of a prototype DEVU25.20h, variable gap hybrid undulator at IDD laboratory, DAVV, Indore, India. The undulator is NdFeB based hybrid undulator with twenty five period and 20 mm each period length. Low cost M35 grade cobalt steel is used as the pole material of the undulator. The abc coefficients of the new pole material is prescribed and the measured performance and characteristics of the undulator is evaluated using RADIA. The detailed design parameters and performance indicators are summarized in Table 1 and Table 2 respectively.

Altmetrics: nuevos indicadores para la comunicación científica en la Web 2.0

Directory of Open Access Journals (Sweden)

Daniel Torres Salinas

2013-08-01

Full Text Available En el presente trabajo se realiza una revisión de las altmetrics o indicadores alternativos. Este concepto se define como la creación y estudio de nuevos indicadores, basados en la web 2.0, para el análisis de la actividad científica y académica. La idea que subyace es que, por ejemplo, las menciones en blogs, el número de tuits o el de personas que guardan un artículo en su gestor de referencias puede ser una medida válida del uso y repercusión de las publicaciones científicas. En este sentido, estas medidas se han situado en el centro del debate de los estudios bibliométricos cobrando especial relevancia. En el artículo se ilustran en primer lugar las plataformas e indicadores principales de este tipo de medidas, para posteriormente estudiar un conjunto de trabajos del ámbito de la comunicación, comparando el número de citas recibidas con sus indicadores 2.0. Los resultados señalan que los artículos más citados de la disciplina en los últimos años también presentan indicadores significativamente más elevados de altmetrics. Seguidamente se realiza un repaso por los principales estudios empíricos realizados, deteniéndonos en las correlaciones entre indicadores bibliométricos y alternativos. Se finaliza, a modo de reflexión, señalando las principales limitaciones y el papel que las altmetrics pueden desempeñar a la hora de captar la repercusión de la investigación en las plataformas de la web 2.0.

Teaching Web 2.0 technologies using Web 2.0 technologies.

Science.gov (United States)

Rethlefsen, Melissa L; Piorun, Mary; Prince, J Dale

2009-10-01

The research evaluated participant satisfaction with the content and format of the "Web 2.0 101: Introduction to Second Generation Web Tools" course and measured the impact of the course on participants' self-evaluated knowledge of Web 2.0 tools. The "Web 2.0 101" online course was based loosely on the Learning 2.0 model. Content was provided through a course blog and covered a wide range of Web 2.0 tools. All Medical Library Association members were invited to participate. Participants were asked to complete a post-course survey. Respondents who completed the entire course or who completed part of the course self-evaluated their knowledge of nine social software tools and concepts prior to and after the course using a Likert scale. Additional qualitative information about course strengths and weaknesses was also gathered. Respondents' self-ratings showed a significant change in perceived knowledge for each tool, using a matched pair Wilcoxon signed rank analysis (P<0.0001 for each tool/concept). Overall satisfaction with the course appeared high. Hands-on exercises were the most frequently identified strength of the course; the length and time-consuming nature of the course were considered weaknesses by some. Learning 2.0-style courses, though demanding time and self-motivation from participants, can increase knowledge of Web 2.0 tools.

Hot rolling of chromium - nickel - manganese stainless steel containing nitrogen and boron

International Nuclear Information System (INIS)

Khorosh, V.A.; Bulat, S.I.; Mukhina, M.A.; Sorokina, N.A.; Yushchenko, K.A.; Tsentral'nyj Nauchno-Issledovatel'skij Inst. Chernoj Metallurgii, Moscow; AN Ukrainskoj SSR, Kiev. Inst. Ehlektrosvarki)

1976-01-01

The strength of stainless steel of the 03Kh2ON16AG6 type increases perceptibly with an increase in the nitrogen content from 0.11 to 0.37%. At the same time, however, its ductility in the region of hot deformation temperatures (red brittleness range of 800 to 1,000 deg C) decreases. Microalloying with boron (0.002 to 0.005% by calculation) permits enhancing the hot ductility to an acceptable level without adversely affecting the working properties. The mechaniusm of boron effect is analyzed. The temperature at which ingots are heated prior to rolling to achieve the desired effect must be sufficiently low. Optimum condition for two stage heating of 6.2-ton ingots are recommeded

Measurements of e p →e'π+n at 1.6 2.0 GeV and extraction of nucleon resonance electrocouplings at CLAS

Science.gov (United States)

Park, K.; Aznauryan, I. G.; Burkert, V. D.; Adhikari, K. P.; Amaryan, M. J.; Pereira, S. Anefalos; Avakian, H.; Battaglieri, M.; Badui, R.; Bedlinskiy, I.; Biselli, A. S.; Bono, J.; Briscoe, W. J.; Brooks, W. K.; Carman, D. S.; Celentano, A.; Chandavar, S.; Charles, G.; Colaneri, L.; Cole, P. L.; Contalbrigo, M.; Cortes, O.; Crede, V.; D'Angelo, A.; Dashyan, N.; De Vita, R.; De Sanctis, E.; Deur, A.; Djalali, C.; Doughty, D.; Dupre, R.; Egiyan, H.; Alaoui, A. El; Elouadrhiri, L.; Fassi, L. El; Eugenio, P.; Fedotov, G.; Fegan, S.; Fersch, R.; Filippi, A.; Fleming, J. A.; Garillon, B.; Garçon, M.; Gevorgyan, N.; Gilfoyle, G. P.; Giovanetti, K. L.; Girod, F. X.; Joo, H. S.; Goetz, J. T.; Golovatch, E.; Gothe, R. W.; Griffioen, K. A.; Guegan, B.; Guidal, M.; Guo, L.; Hakobyan, H.; Hanretty, C.; Hattawy, M.; Hicks, K.; Holtrop, M.; Hughes, S. M.; Hyde, C. E.; Ilieva, Y.; Ireland, D. G.; Ishkhanov, B. S.; Isupov, E. L.; Jenkins, D.; Jiang, H.; Jo, H. S.; Joo, K.; Joosten, S.; Keller, D.; Khandaker, M.; Kim, A.; Kim, W.; Klein, A.; Klein, F. J.; Kubarovsky, V.; Kuhn, S. E.; Kuleshov, S. V.; Lenisa, P.; Livingston, K.; Lu, H. Y.; MacGregor, I. J. D.; Markov, N.; Martinez, D.; McKinnon, B.; Mokeev, V.; Montgomery, R. A.; Moutarde, H.; Camacho, C. Munoz; Nadel-Turonski, P.; Niccolai, S.; Niculescu, G.; Niculescu, I.; Osipenko, M.; Ostrovidov, A. I.; Paolone, M.; Pasyuk, E.; Peng, P.; Phelps, W.; Phillips, J. J.; Pisano, S.; Pogorelko, O.; Price, J. W.; Procureur, S.; Prok, Y.; Protopopescu, D.; Puckett, A. J. R.; Raue, B. A.; Ripani, M.; Rizzo, A.; Rosner, G.; Rossi, P.; Roy, P.; Sabatié, F.; Salgado, C.; Schott, D.; Schumacher, R. A.; Seder, E.; Sharabian, Y. G.; Simonyan, A.; Skorodumina, Iu.; Smith, E. S.; Smith, G. D.; Sparveris, N.; Stoler, P.; Strakovsky, I. I.; Strauch, S.; Sytnik, V.; Taiuti, M.; Tang, W.; Taylor, C. E.; Tian, Ye; Trivedi, A.; Ungaro, M.; Voskanyan, H.; Voutier, E.; Walford, N. K.; Watts, D. P.; Wei, X.; Weinstein, L. B.; Wood, M. H.; Zachariou, N.; Zana, L.; Zhang, J.; Zhao, Z. W.; Zonta, I.; CLAS Collaboration

2015-04-01

Differential cross sections of the exclusive process e p →e'π+n were measured with good precision in the range of the photon virtuality Q2=1.8 -4.5 GeV2 and the invariant mass range of the π+n final state W =1.6 -2.0 GeV using the Continuous Electron Beam Accelerator Facility Large Acceptance Spectrometer. Data were collected with nearly complete coverage in the azimuthal and polar angles of the n π+ center-of-mass system. More than 37 000 cross-section points were measured. The contributions of the isospin I =1/2 resonances N (1675 ) 5/2-,N (1680 ) 5/2+ , and N (1710 ) 1/2+ were extracted at different values of Q2 using a single-channel, energy-dependent resonance amplitude analysis. Two different approaches, the unitary isobar model and the fixed-t dispersion relations, were employed in the analysis. We observe significant strength of the N (1675 ) 5/2- in the A1 /2 amplitude, which is in strong disagreement with quark models that predict both transverse amplitudes to be strongly suppressed. For the N (1680 ) 5/2+ we observe a slow changeover from the dominance of the A3 /2 amplitude at the real photon point (Q2=0 ) to a Q2 where A1 /2 begins to dominate. The scalar amplitude S1 /2 drops rapidly with Q2 consistent with quark model prediction. For the N (1710 ) 1/2+ resonance our analysis shows significant strength for the A1 /2 amplitude at Q2<2.5 GeV2.

Bibliotecas universitarias 2.0. El caso de España University libraries 2.0. The case of Spain

OpenAIRE

José Luis Herrera Morillas; Ana Castillo Díaz

2011-01-01

En este artículo se recopilan los recursos de la Web 2.0 utilizados por las bibliotecas universitarias españolas y se analizan su finalidad y principales rasgos. Se combina la metodología de la visualización en línea y el análisis de contenido para estudiarla utilización que de dichos recursos hacen las 63 bibliotecas universitarias españolas. Entre las herramientas más empleadas destacan el acceso al OPAC 2.0, las redes sociales y los blogs. Por otra parte, entre los recursos menos empleados...

Mg isotopes and the disappearance of magic N=20 - Laser and beta-NMR studies

CERN Document Server

Kowalska, M

2006-01-01

Collinear laser spectroscopy and beta-NMR spectroscopy with optical pumping were applied at ISOLDE/CERN to measure for the first time the magnetic moments of neutron-rich 27Mg, 29Mg, 31Mg and 33Mg, along with the spins of the two latter. The magnetic moment of 27Mg was derived from its hyperfine structure detected in UV fluorescent light, whereas the nuclear magnetic resonance observed in beta-decay asymmetry from a polarised ensemble of nuclei gave the magnetic moment of 29Mg. For 31Mg and 33Mg, the hyperfine structure and nuclear magnetic resonance gave the spin and the magnetic moment. The preliminary results for 27Mg and 29Mg are consistent with a large neutron shell gap at N=20, whereas data on 31Mg show that for this nucleus N=20 is not a magic number, which is also the case for 33Mg, based on preliminary analysis. Thus, the two latter isotopes belong to the island of inversion.

The Faceted Discrete Growth and Phase Differentiation During the Directional Solidification of 20SiMnMo5 Steel

Science.gov (United States)

Ma, Xiaoping; Li, Dianzhong

2018-07-01

The microstructures, segregation and cooling curve were investigated in the directional solidification of 20SiMnMo5 steel. The typical characteristic of faceted growth is identified. The microstructures within the single cellular and within the single dendritic arm, together with the contradictive segregation distribution against the cooling curve, verify the discrete crystal growth in multi-scales. Not only the single cellular/dendritic arm but also the single martensite zone within the single cellular/dendritic arm is produced by the discrete growth. In the viewpoint of segregation, the basic domain following continuous growth has not been revealed. Along with the multi-scale faceted discrete growth, the phase differentiation happens for both the solid and liquid. The differentiated liquid phases appear and evolve with different sizes, positions, compositions and durations. The physical mechanism for the faceted discrete growth is qualitatively established based on the nucleation of new faceted steps induced by the composition gradient and temperature gradient.

The Faceted Discrete Growth and Phase Differentiation During the Directional Solidification of 20SiMnMo5 Steel

Science.gov (United States)

Ma, Xiaoping; Li, Dianzhong

2018-03-01

The microstructures, segregation and cooling curve were investigated in the directional solidification of 20SiMnMo5 steel. The typical characteristic of faceted growth is identified. The microstructures within the single cellular and within the single dendritic arm, together with the contradictive segregation distribution against the cooling curve, verify the discrete crystal growth in multi-scales. Not only the single cellular/dendritic arm but also the single martensite zone within the single cellular/dendritic arm is produced by the discrete growth. In the viewpoint of segregation, the basic domain following continuous growth has not been revealed. Along with the multi-scale faceted discrete growth, the phase differentiation happens for both the solid and liquid. The differentiated liquid phases appear and evolve with different sizes, positions, compositions and durations. The physical mechanism for the faceted discrete growth is qualitatively established based on the nucleation of new faceted steps induced by the composition gradient and temperature gradient.

Microstructural characterization of WC-TiC-Co cutting tools during high-speed machining of P20 mold steel

International Nuclear Information System (INIS)

Farhat, Z.N.

2003-01-01

The wear behavior of tungsten carbide (WC)-TiC-Co cutting tools during cutting P20 tool steel was investigated. Orthogonal cutting tests were performed on a CNC lathe using five speeds, namely, 60, 120, 240, 380 and 600 m/min. Wear, as the width of the wear land, was monitored at five time intervals. Wear characterization of the rake and the flank surfaces as well as the collected chips was performed using scanning electron microscopy (SEM), backscattered electron imaging and energy-dispersive X-ray analysis (EDX). Microhardness of collected chips was also performed to monitor strain hardening effects during cutting. Two dominant wear mechanisms were identified: at high speed (380-600 m/min), wear was found to occur by a melt wear mechanism; at low speed (60-120 m/min), adhesion (built-up edge) followed by delamination was found to be the cause of wear damage. It was also found that deformation in the chips occurred by localized shear deformation

Theoretical and experimental investigations into rare earth oxides behaviour during out of furnace treatment

International Nuclear Information System (INIS)

Vishkarev, A.F.; Smirnov, B.V.; Krup, Yu.M.

1987-01-01

Theoretical model is developed and technology of metal desulfuration and modification by rear earth metals is tested during out of furnace vacuum treatment, the testing of which has demonstrated its high efficiency. 16KhN3MA steel was melted in 120-t open-hearth furnaces under tapping with treatment by synthetic lime-aluminous slag and subsequent ladle degassing by circulation technique. At the early stage of degassing process cerium oxides together with aluminium were introduced into the vacuum chamber in the quantities of 2.0 and 0.2 kg/t respectively. Two meltings ere performed. Sulfur content in steel reduced from 0.017 and 0.018 up to 0.007 and 0.006%

Morpho-Structural Characterization of WC20Co Deposited Layers

Science.gov (United States)

Tugui, C. A.; Vizureanu, P.

2017-06-01

Hydroelectric power plants use the power of water to produce electricity. In this paper we propose a solution that will increase the efficiency of turbine operation by implementing new innovative technologies to increase the working characteristics by depositing hard thin films of tungsten carbide. For this purpose hard tough deposits with WC20Co and Jet Plasma Jet on X3CrNiMo13-4 stainless steel were used for the realization of the Francis turbine with vertical shaft.

Development of fuel economy 5W-20 gasoline engine oil; Teinenpi 5W-20 gasoline engine yu no kaihatsu

Energy Technology Data Exchange (ETDEWEB)

Akiyama, K; Ueda, F; Kurono, K; Kawai, H; Sugiyama, S [Toyota Motor Corp., Aichi (Japan)

1997-10-01

A 5W-20 gasoline engine oil which improves vehicle fuel efficiency by more than 1.5% relative to a conventional 5W-30 gasoline engine oil was newly developed. Its high fuel economy performance lasts 10,000 km. The viscosity was optimized to satisfy both fuel economy and antiwear performances. Thiadiazole was used to retain the initial fuel economy performance provided by MoDTC. 5 refs., 7 figs., 2 tabs.

Aspectos de seguridad en Web 2.0 y redes sociales

OpenAIRE

Caballero Velasco, María Ángeles

2011-01-01

Este proyecto final de carrera de universidad va enfocado a la seguridad en la Web 2.0 y las redes sociales. El documento se divide en dos partes. La primera parte define la visión principal del mundo 2.0, cómo nació y que implicaciones tiene hoy en día en la sociedad. Se definen las características de la Web 2.0 y su historia. Se analizan las diferencias entre la Web 2.0 y la Web 1.0, llegando hasta la Web 3.0. Se clasifican los tipos de Web 2.0 por uso y por aplicación y se analizan todas l...

Second amorphous-to-crystalline phase transformation in Cu(60)Ti(20)Zr(20) bulk metallic glass.

Science.gov (United States)

Cao, Q P; Li, J F; Zhang, P N; Horsewell, A; Jiang, J Z; Zhou, Y H

2007-06-20

The second amorphous-to-crystalline phase transformation in Cu(60)Ti(20)Zr(20) bulk metallic glass was investigated by differential scanning calorimetry and x-ray diffractometry. The difference of the Gibbs free energies between the amorphous phase and the crystalline products during the transformation is estimated to be about 2.46 kJ mol(-1) at 753 K, much smaller than the 61 kJ mol(-1) obtained assuming that it is a polymorphic transformation. It was revealed that the phase transformation occurs through a eutectic crystallization of Cu(51)Zr(14) and Cu(2)TiZr, having an effective activation energy of the order of 400 kJ mol(-1). The average Avrami exponent n is about 2.0, indicating that the crystallization is diffusion controlled.

26 CFR 20.2014-4 - Application of credit in cases involving a death tax convention.

Science.gov (United States)

2010-04-01

..., indebtedness, etc., amounted to $50,000. Decedent left his entire estate to his son. There is in effect a death... death tax convention. 20.2014-4 Section 20.2014-4 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT... 16, 1954 Credits Against Tax § 20.2014-4 Application of credit in cases involving a death tax...

Submerged arc narrow gap welding of the steel DIN 20MnMoNi55

International Nuclear Information System (INIS)

Moraes, M.M.

1987-01-01

The methodology for submerged arc narrow gap welding for high thickness rolled steel DIN 20MnMoNi55 was developed, using din S3NiMo1 04 mm and 05 mm wires, and DIN 8B435 flux. For this purpose, submerged arc narrow gap welded joints with 50 mm and 120 mm thickness were made aiming the welding parameters optimization and the study of the influence of welding voltage, wire diameter and wire to groove face distance on the operational performance and on the welded joint quality, specially on the ISO-V impact toughness. These welded joints were checked by non-destructive mechanical and metallographic tests. Results were compared with those obtained by one 120 mm thickness submerged arc conventional gap welded joint, using the same base metal and consumables (05 mm wire). The analysis of the results shows that the increasing of the wire to groove face distance and the welding voltage increases the hardness and the ISO-V impact toughness of the weld metal. It shows that the reduction of the gap angle is the main cause for the obtained of a heat affected zone free from coarse grains, the reduction of the welding voltage, the increasing of the wire to groove face distance, and the grounding optimization also contribute for that. It was also concluded that the quality and the execution complexity level of a narrow gap welded joint are identical to a conventional gap welded joint. (author) [pt

Study of radiation damage of steels for light water pressure vessels at UJV

International Nuclear Information System (INIS)

Vacek, N.; Stoces, B.

1980-01-01

Preoperational determination of radiation resistance of pressure vessel steels is performed at accelerated neutron exposure in a test or materials research reactor. The results obtained at accelerated and operating exposure are not fully identical and surveillance bodies are therefore used manufactured from the pressure vessel material. Currently, the following steels are used for the manufacture of light water reactor pressure vessels: Mn-Mo-Ni (ASTM-A533-B, ASTM-A508), Cr-Mo-V (15Kh2M1FA). At UJV Rez, for irradiation Chanca-M probes imported from France are used featuring electric temperature control. Almost identical radiation embrittlement was measured for all three steels after irradiation with a neutron fluence of 3x10 23 n.m -2 at a temperature of 290 degC. (H.S.)

Alterations of global histone H4K20 methylation during prostate carcinogenesis

Directory of Open Access Journals (Sweden)

Behbahani Turang E

2012-03-01

Full Text Available Abstract Background Global histone modifications have been implicated in the progression of various tumour entities. Our study was designed to assess global methylation levels of histone 4 lysine 20 (H4K20me1-3 at different stages of prostate cancer (PCA carcinogenesis. Methods Global H4K20 methylation levels were evaluated using a tissue microarray in patients with clinically localized PCA (n = 113, non-malignant prostate disease (n = 27, metastatic hormone-naive PCA (mPCA, n = 30 and castration-resistant PCA (CRPC, n = 34. Immunohistochemistry was performed to assess global levels of H4K20 methylation levels. Results Similar proportions of the normal, PCA, and mPCA prostate tissues showed strong H4K20me3 staining. CRPC tissue analysis showed the weakest immunostaining levels of H4K20me1 and H4K20me2, compared to other prostate tissues. H4K20me2 methylation levels indicated significant differences in examined tissues except for normal prostate versus PCA tissue. H4K20me1 differentiates CRPC from other prostate tissues. H4K20me1 was significantly correlated with lymph node metastases, and H4K20me2 showed a significant correlation with the Gleason score. However, H4K20 methylation levels failed to predict PSA recurrence after radical prostatectomy. Conclusions H4K20 methylation levels constitute valuable markers for the dynamic process of prostate cancer carcinogenesis.

Evolution of the structure and the phase composition of a bainitic structural steel during plastic deformation

Science.gov (United States)